Background:The essential roles of platelets in thrombosis have been well recognized.Unexpectedly,thrombosis is prevalent during thrombocytopenia induced by cytotoxicity of biological,physical and chemical origins,whic...Background:The essential roles of platelets in thrombosis have been well recognized.Unexpectedly,thrombosis is prevalent during thrombocytopenia induced by cytotoxicity of biological,physical and chemical origins,which could be suffered by military personnel and civilians during chemical,biological,radioactive,and nuclear events.Especially,thrombosis is considered a major cause of mortality from radiation injury-induced thrombocytopenia,while the underlying pathogenic mechanism remains elusive.Methods:A mouse model of radiation injury-induced thrombocytopenia was built by exposing mice to a sublethal dose of ionizing radiation(IR).The phenotypic and functional changes of platelets and megakaryocytes(MKs)were determined by a comprehensive set of in vitro and in vivo assays,including flow cytometry,flow chamber,histopathology,Western blotting,and chromatin immunoprecipitation,in combination with transcriptomic analysis.The molecular mechanism was investigated both in vitro and in vivo,and was consolidated using MK-specific knockout mice.The translational potential was evaluated using a human MK cell line and several pharmacological inhibitors.Results:In contrast to primitive MKs,mature MKs(mMKs)are intrinsically programmed to be apoptosis-resistant through reprogramming the Bcl-xL-BAX/BAK axis.Interestingly,mMKs undergo minority mitochondrial outer membrane permeabilization(MOMP)post IR,resulting in the activation of the cyclic GMP-AMP synthase-stimulator of IFN genes(cGAS-STING)pathway via the release of mitochondrial DNA.The subsequent interferon-β(IFN-β)response in mMKs upregulates a GTPase guanylate-binding protein 2(GBP2)to produce large and hyperreactive platelets that favor thrombosis.Further,we unmask that autophagy restrains minority MOMP in mMKs post IR.Conclusions:Our study identifies that megakaryocytic mitochondria-cGAS/STING-IFN-β-GBP2 axis serves as a fundamental checkpoint that instructs the size and function of platelets upon radiation injury and can be harnessed to treat platelet pathologies.展开更多
BACKGROUND Neonatal sepsis,a formidable threat to newborns,is a leading cause of neonatal mortality,with late-onset sepsis manifesting after 72 hours post-birth being particularly concerning.Pneumonia,a prevalent seps...BACKGROUND Neonatal sepsis,a formidable threat to newborns,is a leading cause of neonatal mortality,with late-onset sepsis manifesting after 72 hours post-birth being particularly concerning.Pneumonia,a prevalent sepsis presentation,poses a significant risk,especially during the neonatal phase when lung defenses are compromised.Accurate diagnosis of pneumonia is imperative for timely and effective interventions.Saliva,a minimally invasive diagnostic medium,holds great promise for evaluating infections,especially in infants.AIM To investigate the potential of serum C-reactive protein(CRP),salivary CRP(sCRP),and mean platelet volume(MPV)as diagnostic markers for late-onset neonatal pneumonia(LONP).METHODS Eighty full-term neonates were systematically examined,considering anthropometric measurements,clinical manifestations,radiology findings,and essential biomarkers,including serum CRP,sCRP,and MPV.RESULTS The study reveals noteworthy distinctions in serum CRP levels,MPV,and the serum CRP/MPV ratio between neonates with LONP and healthy controls.MPV exhibited a robust discriminatory ability[area under the curve(AUC)=0.87]with high sensitivity and specificity at a cutoff value of>8.8.Correlations between serum CRP,sCRP,and MPV were also identified.Notably,sCRP demonstrated excellent predictive value for serum CRP levels(AUC=0.89),underscoring its potential as a diagnostic tool.CONCLUSION This study underscores the diagnostic promise of salivary and serum biomarkers,specifically MPV and CRP,in identifying and predicting LONP among neonates.These findings advocate for further research to validate their clinical utility in larger neonatal cohorts.展开更多
Platelet rich plasma(PRP)is an autologous blood product rich in platelets,showing promise in reducing inflammation and accelerating healing.While extensively utilized in plastic surgery,dermatology,and osteoarthritis ...Platelet rich plasma(PRP)is an autologous blood product rich in platelets,showing promise in reducing inflammation and accelerating healing.While extensively utilized in plastic surgery,dermatology,and osteoarthritis treatment,its application in anterior cruciate ligament(ACL)injuries is limited.This article examines PRP's potential in ACL reconstruction(ACLR),exploring its history,current usage,controversies and future directions.PRP has demonstrated significant early benefits in ligamentisation and vascularisation post-ACLR,though its long-term efficacy is inconsistent.Studies suggest that PRP may serve as both an adjunct therapy in ACLR to enhance initial healing and reduce postoperative complications,and as a non-surgical alternative for small ACL tears.Despite these promising findings,outcome variability necessitates further high-quality research to optimize PRP formulations and determine its most effective applications.The exploration of PRP as a treatment modality in ACLR offers promising but varied outcomes.PRP holds considerable promise as both an adjunct and alternative to traditional ACLR.This article underscores the need for targeted research to fully realize PRP's therapeutic potential in ACL treatment,aiming to inform future studies and clinical practices.By understanding PRP's mechanisms of efficacy and identifying the most beneficial patient populations,PRP could significantly impact orthopaedics and sports medicine,improving recovery pathways and patient outcomes.展开更多
Platelets are small anucleate cells generated from megakaryocytes in the bone marrow. Although platelet genera- tion, maturation, and clearance are still not fully understood, significant progress has been made in the...Platelets are small anucleate cells generated from megakaryocytes in the bone marrow. Although platelet genera- tion, maturation, and clearance are still not fully understood, significant progress has been made in the last 1-2 dec- ades. In blood circulation, platelets can quickly adhere and aggregate at sites of vascular injury, forming the platelet plug (i.e. the first wave of hemostasis). Activated platelets can also provide negatively charged phosphatidylserine- rich membrane surface that enhances cell-based thrombin generation, which facilitates blood coagulation (i.e. the second wave of hemostasis). Platelets therefore play central roles in hemostasis. However, the same process of hemostasis may also cause thrombosis and vessel occlusion, which are the most common mechanisms leading to heart attack and stroke following ruptured atherosclerotic lesions. In this review, we will introduce the classical mechanisms and newly discovered pathways of platelets in hemostasis and thrombosis, including fibrinogen-inde- pendent platelet aggregation and thrombosis, and the plasma fibronectin-mediated "protein wave" of hemostasis that precedes the classical first wave of hemostasis. Furthermore, we briefly discuss the roles of platelets in inflam- marion and atherosclerosis and the potential strategies to control atherothrombosis.展开更多
Although viral hepatitis treatments have evolved over the years, the resultant liver cirrhosis still does not completely heal. Platelets contain proteins required for hemostasis, as well as many growth factors require...Although viral hepatitis treatments have evolved over the years, the resultant liver cirrhosis still does not completely heal. Platelets contain proteins required for hemostasis, as well as many growth factors required for organ development, tissue regeneration and repair. Thrombocytopenia, which is frequently observed in patients with chronic liver disease(CLD) and cirrhosis, can manifest from decreased thrombopoietin production and accelerated platelet destruction caused by hypersplenism; however, the relationship between thrombocytopenia and hepatic pathogenesis, as well as the role of platelets in CLD, is poorly understood. In this paper, experimental evidence of platelets improving liver fibrosis and accelerating liver regeneration is summarized and addressed based on studies conducted in our laboratory and current progress reports from other investigators. In addition, we describe our current perspective based on the results of these studies. Platelets improve liver fibrosis by inactivating hepatic stellate cells, which decreases collagen production. The regenerative effect of platelets in the liver involves a direct effect on hepatocytes, a cooperative effect with liver sinusoidal endothelial cells, and a collaborative effect with Kupffer cells. Based on these observations, we ascertained the direct effect of platelet transfusion on improving several indicators of liver function in patients with CLD and liver cirrhosis. However, unlike the results of our previous clinical study, the smaller incremental changes in liver function in patients with CLD who received eltrombopag for 6 mo were due to patient selection from a heterogeneous population. We highlight the current knowledge concerning the role of platelets in CLD and cancer and anticipate a novel application of platelet-based clinical therapies to treat liver disease.展开更多
Major depression is an independent risk factor for cardiovascular mortality and morbidity. The exact mechanisms linking depression and increased cardiovascular risk remain poorly understood. Several mechanisms have be...Major depression is an independent risk factor for cardiovascular mortality and morbidity. The exact mechanisms linking depression and increased cardiovascular risk remain poorly understood. Several mechanisms have been proposed including increased platelet reactivity. This review focuses on the current literature that examines the platelet hypothesis of depression. To date studies show increased serotonin response, increased platelet serotonin receptor density, decreased serotonin transporter binding, and decreased platelet serotonin levels in individuals with depression. However other studies have shown no change in serotonin uptake. In addition to platelet serotonin specific pathways, other platelet pathways that have shown significant changes in depressed individuals include blunting of the platelet adenosine response, increased platelet thrombin response, increased glycoprotein Ⅰb expression, increased P-selectin, β thromboglobulin, and platelet factor four, as well as decreased platelet brain derived neurotrophic factor. However there are other studies that show conflicting evidence of increased platelet activation as measured by integrin receptor α2b β3. Other conflictingdata include α adrenergic density and platelet response to augmented serotonin. The direction of future research in platelet functional changes in depression and coronary artery disease should continue to focus on serotonin specific pathways with emphasis on potential mechanisms of specific pathway changes.展开更多
AIM To provide a simple surrogate marker predictive of liver cirrhosis(LC).METHODS Specimens from 302 patients who underwent resection for hepatocellular carcinoma between January 2006 and December 2012 were retrospec...AIM To provide a simple surrogate marker predictive of liver cirrhosis(LC).METHODS Specimens from 302 patients who underwent resection for hepatocellular carcinoma between January 2006 and December 2012 were retrospectively analyzed. Based on pathologic findings, patients were divided into groups based on whether or not they had LC. Parameters associated with hepatic functional reserve were compared in these two groups using MannWhitney U-test for univariate analysis. Factors differing significantly in univariate analyses were entered into multivariate logistic regression analysis.RESULTS There were significant differences between the LC group(n = 100) and non-LC group(n = 202) in prothrombin activity, concentrations of alanine aminotransferase, aspartate aminotransferase, total bilirubin, albumin, cholinesterase, type Ⅳ collagen, hyaluronic acid, indocyanine green retention rate at 15 min, maximal removal rate of technitium-99 m diethylene triamine pentaacetic acid-galactosyl human serum albumin and ratio of mean platelet volume to platelet count(MPV/PLT). Multivariate analysis showed that prothrombin activity, concentrations of alanine aminotransferase, aspartate aminotransferase, total bilirubin and hyaluronic acid, and MPV/PLT ratio were factors independently predictive of LC. The area under the curve value for MPV/PLT was 0.78,with a 0.8 cutoff value having a sensitivity of 65% and a specificity of 78%.CONCLUSION The MPV/PLT ratio, which can be determined simply from the complete blood count, may be a simple surrogate marker predicting LC.展开更多
AIM:To investigate the role of human platelets in liver fibrosis.METHODS:Severe combined immunodeficiency(SCID)mice were administered CCl4and either phosphate-buffered saline(PBS group)or human platelet transfusions(h...AIM:To investigate the role of human platelets in liver fibrosis.METHODS:Severe combined immunodeficiency(SCID)mice were administered CCl4and either phosphate-buffered saline(PBS group)or human platelet transfusions(hPLT group).Concentrations of hepatocyte growth factor(HGF),matrix metallopeptidases(MMP)-9,and transforming growth factor-β(TGF-β)in the liver tissue were compared between the PBS and the hPLT groups by enzyme-linked immunosorbent assay(ELISA)and Western blotting.The effects of a human platelet transfusion on liver fibrosis included the fibrotic area,hydroxyproline content,and-smooth muscle actin(α-SMA)expression,which were evaluated by picrosirius red staining,ELISA,and immunohistochemical staining using an anti-mouse-SMA antibody,respectively.Phosphorylations of mesenchymal-epithelial transition factor(Met)and SMAD3,downstream signals of HGF and TGF-β,were compared between the two groups by Western blotting and were quantified using densitometry.Hepatocyte apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling.Furthermore,the accumulation of human platelets in the liver 2 h after platelet transfusion was compared between normal and fibrotic livers by immunohistochemical staining using an anti-human CD41 antibody.RESULTS:The fibrotic area and hydroxyproline content in the liver were both significantly lower in the hPLT group when compared to the PBS group(fibrotic area,1.7%±0.6%vs 2.5%±0.6%,P=0.03;hydroxyproline content,121±26 ng/g liver vs 156±47 ng/g liver,P=0.04).There was less α-smooth muscle actin staining in the hPLT group than in the PBS group(0.5%±0.1%vs 0.8%±0.3%,P=0.02).Hepatic expression levels of mouse HGF and MMP-9were significantly higher in the hPLT group than in the PBS group(HGF,109±13 ng/g liver vs 88±22 ng/g liver,P=0.03;MMP-9,113%±7%/GAPDH vs 92%±11%/GAPDH,P=0.04).In contrast,the concentration of mouse TGF-β in the liver tissue was significantly lower in the hPLT group than in the PBS group(22±5ng/g liver vs 39±6 ng/g liver,P=0.02).Phosphorylation of Met was more prevalent in the hPLT group than in the PBS group(37%±4%/GAPDH vs 20%±8%/GAPDH,P=0.03).Phosphorylation of SMAD3was weaker in the hPLT group than in the PBS group(60%±12%/GAPDH vs 84%±12%/GAPDH,P=0.1),although this difference was not significant.Furthermore,a lower rate of hepatocyte apoptosis was observed in the hPLT group than in the PBS group(5.9%±1.7%vs 2.9%±2.1%,P=0.02).Significant human platelet accumulation was observed in the fibrotic liver tissues,whereas few platelets accumulated in the normal liver.CONCLUSION:Human platelets inhibit liver fibrosis in SCID mice.Increased concentration of HGF in the liver suppresses hepatic stellate cell activation,induces MMPs,and inhibits hepatocyte apoptosis.展开更多
AIM To investigate serum mean platelet volume(MPV) levels in acute pancreatitis(AP) patients and assess whether MPV effectively predicts the disease severity of AP.METHODS We included 117 consecutive patients with AP ...AIM To investigate serum mean platelet volume(MPV) levels in acute pancreatitis(AP) patients and assess whether MPV effectively predicts the disease severity of AP.METHODS We included 117 consecutive patients with AP as the AP group and 34 consecutive patients with colorectal polyps(before endoscopic treatment) as the control group. Complete blood counts, liver function, platelet indices(MPV), coagulation parameters, lactate dehydrogenase(LDH) and C-reactive protein(CRP) were measured on days 1, 2, 3 and 7 after admission. Receiver operating characteristic curves were used to compare the sensitivity and specificity of MPV, white blood cell(WBC), LDH and CRP in predicting AP severity. The Modified Glasgow Prognostic Score(m GPS) and the 2012 revised Atlanta criteria were used to evaluate disease severity in AP.RESULTS MPV levels were significantly lower in the AP group than in the control group on day 1(P = 0.000), day 2(P = 0.029) and day 3(P = 0.001) after admission.In addition, MPV values were lower on day 1 after admission than on day 2(P = 0.012), day 3(P = 0.000) and day 7(P = 0.002) in all AP patients. Based on the m GPS, 78 patients(66.7%) were diagnosed with mild and 39 patients(33.3%) with severe AP. There was no significant difference in mean MPV levels between patients diagnosed with mild and severe AP based on the m GPS(P = 0.424). According to the 2012 revised Atlanta criteria, there were 98 patients(83.8%) without persistent organ failure(OF) [non-severe acute pancreatitis(non-SAP) group] and 19 patients(16.2%) with persistent OF(SAP group). MPV levels were significantly lower in the SAP group than in the non-SAP group on day 1 after admission(P = 0.002). On day 1 after admission using a cut-off value of 6.65 f L, the overall accuracy of MPV for predicting SAP according to the 2012 revised Atlanta criteria(AUC = 0.716) had a sensitivity of 91.8% and a specificity of 47.4% and was superior to the accuracy of the traditional markers WBC(AUC = 0.700) and LDH(AUC = 0.697).CONCLUSION MPV can be used at no additional cost as a useful, noninvasive biomarker that distinguishes AP with persistent OF from AP without persistent OF on day 1 of hospital admission.展开更多
There is evidence that inflammatory bowel diseases (IBD) combine both inflammation and coagulation in their pathogenesis and clinical manifestations. Although platelets (PLT) are well known for their role in hemostasi...There is evidence that inflammatory bowel diseases (IBD) combine both inflammation and coagulation in their pathogenesis and clinical manifestations. Although platelets (PLT) are well known for their role in hemostasis, there are a rising number of studies supporting their considerable role as inflammatory amplifiers in chronic inflammatory conditions. IBD are associated with several alterations of PLT, including number, shape, and function, and these abnormalities are mainly attributed to the highly activated state of circulating PLT in IBD patients. When PLT activate, they increase in size, release a great variety of bio-active inflammatory and procoagulant molecules/particles, and express a variety of inflammatory receptors. These inflammatory products may represent a part of the missing link between coagulation and inflammation, and can be considered as possible IBD pathogenesis instigators. In clinical practice, thrombocytosis is associated both with disease activity and iron deficiency anemia. Controlling inflammation and iron replacement in anemic patients usually leads to a normalization of PLT count. The aim of this review is to update the role of PLT in IBD and present recent data revealing the possible therapeutic implications of anti-PLT agents in future IBD remedies.展开更多
AIM: To investigate the effect of mild steatotic liver on ischemia-reperfusion injury by focusing on Kupffer cells (KCs) and platelets. METHODS: Wistar rats were divided into a normal liver group (N group) and a mild ...AIM: To investigate the effect of mild steatotic liver on ischemia-reperfusion injury by focusing on Kupffer cells (KCs) and platelets. METHODS: Wistar rats were divided into a normal liver group (N group) and a mild steatotic liver group (S group) induced by feeding a choline-deficient diet for 2 wk. Both groups were subjected to 20 min of warm ischemia followed by 120 min of reperfusion. The number of labeled KCs and platelets in sinusoids and the blood perfusion in sinusoids were observed by intravital microscopy (IVM), which was performed at 30, 60 and 120 min after reperfusion. To evaluate serum alanine aminotransferase as a marker of liver deterioration, blood samples were taken at the same time as IVM.RESULTS: In the S group, the number of platelets adhering to KCs decreased significantly compared with the N group (120 after reperfusion; 2.9±1.1 cells/acinus vs 4.8±1.2 cells/acinus, P<0.01). The number of KCs in sinusoids was significantly less in the S group than in the N group throughout the observation periods (before ischemia, 19.6±3.3 cells/acinus vs 28.2±4.1 cells/acinus, P<0.01 and 120 min after reperfusion, 29.0±4.3 cells/acinus vs 40.2±3.3 cells/acinus, P<0.01). The blood perfusion of sinusoids 120 min after reperfusion was maintained in the S group more than in the N group. Furthermore, elevation of serum alanine aminotransferase was lower in the S group than in the N group 120 min after reperfusion (99.7±19.8 IU/L vs 166.3±61.1 IU/L, P=0.041), and histological impairment of hepatocyte structure was prevented in the S group. CONCLUSION: Ischemia-reperfusion injury in mild steatotic liver was attenuated compared with normal liver due to the decreased number of KCs and the reduction of the KC-platelet interaction.展开更多
Well-crystallized hexagonal hematite (α-Fe2O3) platelets were synthesized by hydrothermal process, using a highly concentrated ferric hydroxide as precursor. The precursor was prepared by adding ammonia to the ferr...Well-crystallized hexagonal hematite (α-Fe2O3) platelets were synthesized by hydrothermal process, using a highly concentrated ferric hydroxide as precursor. The precursor was prepared by adding ammonia to the ferric sulfate solution which was obtained by leaching pyrite cinders with sulfuric acid. Structure and morphology of the synthesized products were investigated by X-ray diffraction, scanning electron microscope, transmission electron microscope and selected area electron diffraction. The results reveal that the reaction temperature has significant effects on the structure, size and shape of the synthesized hematite particles. Typical hexagonal hematite platelets, about 0.4-0.6 μm in diameter and 0.1 μm in thickness, were prepared at 230 ℃ for 0.5 h. Al^3+, contained in the sulfuric acid leaching solution as an impurity, plays an extremely important role in the formation of hexagonal hematite. In addition, a possible mechanism about the formation of hexagonal hematite platelets was proposed.展开更多
The thermal vibration of functionally graded(FG)porous nanocomposite beams reinforced by graphene platelets(GPLs)is studied.The beams are exposed to the thermal gradient with a multilayer structure.The temperature var...The thermal vibration of functionally graded(FG)porous nanocomposite beams reinforced by graphene platelets(GPLs)is studied.The beams are exposed to the thermal gradient with a multilayer structure.The temperature varies linearly across the thickness direction.Three different types of dispersion patterns of GPLs as well as porosity distributions are presented.The material properties vary along the thickness direction.By using the mechanical parameters of closed-cell cellular solid,the variation of Poisson’s ratio and the relation between the porosity coefficient and the mass density under the Gaussian random field(GRF)model are obtained.By using the Halpin-Tsai micromechanics model,the elastic modulus of the nanocomposite is achieved.The equations of motion based on the Timoshenko beam theory are obtained by using Hamilton’s principle.These equations are discretized and solved by using the generalized differential quadrature method(GDQM)to obtain the fundamental frequencies.The effects of the weight fraction,the dispersion model,the geometry,and the size of GPLs,as well as the porosity distribution,the porosity coefficient,the boundary condition,the metal matrix,the slenderness ratio,and the thermal gradient are presented.展开更多
The effects of different additives on the mechanical properties, microstructures, and wear behavior of corundum abra- sives were investigated. When the number of additive phases increases, the sintering temperature an...The effects of different additives on the mechanical properties, microstructures, and wear behavior of corundum abra- sives were investigated. When the number of additive phases increases, the sintering temperature and wear rate decrease, while the densification and mechanical properties increase. The additive SiO2 is responsible for the development of equiaxed grains, whereas both CaO and MgO promote the development of platelike grains. By controlling the molar ratio of additives, it is pos- sible to obtain different microstructures. With SiO2-MgO-CaO (molar ratio, 2:1:1) as the additives and nano a-Al203 powders as the seed, microcrystalline corundum abrasives with hexagonal platelets were obtained using sol-gel process by sintering at 1300℃ for 0.5 h. The average diameter and thickness of hexagonal platelets are 1.38 μm and 360 nm respectively, the sin- gle-particle compressive strength is 26.44 N, and the wear rate is (3.06±=0.21)× 10^-7 mm^3/(N.m).展开更多
Background: Lower mean platelet volume(MPV) is an indicator of platelet activity in the setting of tumor development. This study was to assess the relationship between preoperative MPV and survival outcomes of patient...Background: Lower mean platelet volume(MPV) is an indicator of platelet activity in the setting of tumor development. This study was to assess the relationship between preoperative MPV and survival outcomes of patients with hepatocellular carcinoma(HCC) following liver transplantation(LT). Methods: The demographic and clinical characteristics of 304 HCC patients following LT were retrieved from an LT database. All the patients were divided into the normal and lower MPV groups according to the median MPV. The factors were first analyzed using a Kaplan–Meier survival analysis, then the factors with P < 0.10 were selected for multivariate Cox regression analysis and were used to define the independent risk factors for poor prognosis. Results: The 1-, 3-, and 5-year tumor free survival was 95.34%, 74.67% and 69.29% in the normal MPV group, respectively, and 95.40%, 59.97% and 42.94% in the lower MPV group, respectively( P < 0.01). No significant difference was observed in post-LT complications between the normal and lower MPV groups. Portal vein tumor thrombosis(PVTT)[hazard ratio(HR = 2.24;95% confidence interval: 1.46–3.43;P < 0.01) and lower MPV(HR = 1.58;95% confidence interval: 1.05–2.36;P = 0.03) were identified as independent prognostic risk factors for recipient survival. Conclusion: Preoperative lower MPV is a risk indicator of HCC patients survival outcomes after LT.展开更多
The high mortality rate of breast cancer is mainly caused by the metastatic ability of cancer cells,resistance to chemotherapy and radiotherapy,and tumor regression capacity.In recent years,it has been shown that the ...The high mortality rate of breast cancer is mainly caused by the metastatic ability of cancer cells,resistance to chemotherapy and radiotherapy,and tumor regression capacity.In recent years,it has been shown that the presence of breast cancer stem cells is closely associated with the migration and metastatic ability of cancer cells,as well as with their resistance to chemotherapy and radiotherapy.The tumor microenvironment is one of the main molecular factors involved in cancer and metastatic processes development,in this sense it is interesting to study the role of platelets,one of the main communicator cells in the human body which are activated by the signals they receive from the microenvironment and can generate more than one response.Platelets can ingest and release RNA,proteins,cytokines and growth factors.After the platelets interact with the tumor microenvironment,they are called"tumor-educated platelets."Tumor-educated platelets transport material from the tumor microenvironment to sites adjacent to the tumor,thus helping to create microenvironments conducive for the development of primary and metastatic tumors.It has been observed that the clone capable of carrying out the metastatic process is a cancer cell with stem cell characteristics.Cancer stem cells go through a series of processes,including epithelial-mesenchymal transition,intravasation into blood vessels,movement through blood vessels,extravasation at the site of the establishment of a metastatic focus,and site colonization.Tumor-educated platelets support all these processes.展开更多
BACKGROUND Preoperative pulmonary function plays an important role in selecting surgical candidates and assessing postoperative complications.Reduced pulmonary function is associated with poor survival in several canc...BACKGROUND Preoperative pulmonary function plays an important role in selecting surgical candidates and assessing postoperative complications.Reduced pulmonary function is associated with poor survival in several cancers,but the prognostic value of preoperative pulmonary function in esophageal squamous cell carcinoma(ESCC)is unclear.Nutritional and systemic inflammation parameters are vital to cancer survival,and the combination of these parameters improves the prognostic value.The hemoglobin,albumin,lymphocytes and platelets(HALP)score is a novel prognostic indicator to reflect the nutritional and inflammation status,but the clinical effects of the HALP score combined with maximal voluntary ventilation(MVV),an important parameter of pulmonary function,have not been well studied in ESCC.AIM To investigate the prognostic value of MVV and HALP score for assessing postoperative survival of ESCC patients.METHODS Data form 834 ESCC patients who underwent radical esophagectomy with R0 resection were collected and retrospectively analyzed.Preoperative MVV and HALP data were retrieved from medical archives.The HALP score was calculated by the formula:Hemoglobin(g/L)×albumin(g/L)×lymphocytes(/L)/platelets(/L).The optimal cut-off values of MVV and HALP score were calculated by the receiver operating characteristic curve analysis.The Kaplan-Meier method with log-rank test was used to draw the survival curves for the variables tested.Multivariate Cox proportional hazard regression models were used to analyze the independent prognostic factors for overall survival.RESULTS MVV was significantly associated with gender(P<0.001),age at diagnosis(P<0.001),smoking history(P<0.001),drinking history(P<0.001),tumor length(P=0.013),tumor location(P=0.037)and treatment type(P=0.001).The HALP score was notably associated with gender(P<0.001),age at diagnosis(P=0.035),tumor length(P<0.001)and invasion depth(P=0.001).Univariate Cox regression analysis showed that low MVV and low HALP score were associated with worse overall survival(all P<0.001).Multivariate analysis showed that low MVV and the HALP score were both independent risk factors for overall survival(all P<0.001).The combination of MVV and HALP score improved the prediction performance for overall survival than tumor-node-metastasis.Also,low combination of MVV and HALP score was an independent risk factor for poor overall survival(P<0.001).CONCLUSION MVV,HALP score and their combination are simple and promising clinical markers to predict overall survival of ESCC patients.展开更多
Metastasis is the main cause of cancer-associated mortality. During this complicated process, some cancer cells, also called circulating tumor cells (CTCs), detach from primary sites, enter bloodstream and extravasa...Metastasis is the main cause of cancer-associated mortality. During this complicated process, some cancer cells, also called circulating tumor cells (CTCs), detach from primary sites, enter bloodstream and extravasate at metastatic site. Thrombocytosis is frequently observed in patients with metastatic cancers suggesting the important role of platelets in metastasis. Therefore this review focuses on how platelets facilitate the generation of CTCs, protect them from various host attacks, such as immune assaults, apoptosis and shear stress, and regulate CTCs intravasation/extravasation. Platelet-derived cytokines and receptors are involved in this cascade. Identification the mechanisms underlie platelet-CTCs interactions could lead to the development of new platelet-targeted therapeutic strategy to reduce metastasis.展开更多
Mean platelet volume (MPV) is an early marker ofplatelet activation. Larger platelets, compared to small ones, increase platelet adhesion and aggregation, and present a higher thrombotic activity. Some studies have ...Mean platelet volume (MPV) is an early marker ofplatelet activation. Larger platelets, compared to small ones, increase platelet adhesion and aggregation, and present a higher thrombotic activity. Some studies have explored the association between MPV and the morbidity of portal vein thrombosis (PVT). The aim of this study was to evaluate the predictive effect of MPV in patients with PVT by a meta-analysis. We searched Pubmed, Web of Science, SCOPUS, OVID, CNKI and CBMD from database inception to September 13, 2017. Seven studies in accordance with selection criteria were included. The extraction of basic data was independently conducted by two reviewers. The mean difference in MPV between PVT patients and controls were pooled with weighted mean difference (WMD) and 95% confidence interval of 0.88 fl (95% CI: 0.61-1.15). A random-effect model was chosen for an obvious heterogeneity in the pooling (Chi-square=27.12, df=6, P〈0.0001, F=77.9%). The sources of heterogeneity were from the difference of primary disease of participants and portal vein diameter. Taken together, our results reveal that MPV is a predictive indicator in patients with PVT.展开更多
Featuring exceptional mechanical and functional performance, MWCNTs and graphene(nano)platelets(GNPs or Gn Ps;each platelet below 10 nm in thickness) have been increasingly used for the development of polymer nanocomp...Featuring exceptional mechanical and functional performance, MWCNTs and graphene(nano)platelets(GNPs or Gn Ps;each platelet below 10 nm in thickness) have been increasingly used for the development of polymer nanocomposites. Since MWCNTs are now cost-effective at US$30 per kg for industrial applications, this work starts by briefly reviewing the disentanglement and surface modification of MWCNTs as well as the properties of the resulting polymer nanocomposites. GNPs can be made through the thermal treatment of graphite intercalation compounds followed by ultrasonication;GNPs would have lower cost yet higher electrical conductivity over 1,400 S cmthan MWCNTs. Through proper surface modification and compounding techniques, both types of fillers can reinforce or toughen polymers and simultaneously add anti-static performance. A high ratio of MWCNTs to GNPs would increase the synergy for polymers. Green, solvent-free systhesis methods are desired for polymer nanocomposites. Perspectives on the limitations, current challenges and future prospects are provided.展开更多
基金supported by the Key Program of the National Natural Science Foundation of China(81930090)the National Science Foundation for Distinguished Young Scholars of China(81725019)+2 种基金the National Natural Science Foundation of China(32171104,82273571,and 81874256)the Chongqing Natural Science Foundation(2023NSCQ-MSX0687,CSTB2023NSCQ-JQX0015,and cstc2015jcyjys10001)the Chongqing Talent Program(CQYC20220511002).
文摘Background:The essential roles of platelets in thrombosis have been well recognized.Unexpectedly,thrombosis is prevalent during thrombocytopenia induced by cytotoxicity of biological,physical and chemical origins,which could be suffered by military personnel and civilians during chemical,biological,radioactive,and nuclear events.Especially,thrombosis is considered a major cause of mortality from radiation injury-induced thrombocytopenia,while the underlying pathogenic mechanism remains elusive.Methods:A mouse model of radiation injury-induced thrombocytopenia was built by exposing mice to a sublethal dose of ionizing radiation(IR).The phenotypic and functional changes of platelets and megakaryocytes(MKs)were determined by a comprehensive set of in vitro and in vivo assays,including flow cytometry,flow chamber,histopathology,Western blotting,and chromatin immunoprecipitation,in combination with transcriptomic analysis.The molecular mechanism was investigated both in vitro and in vivo,and was consolidated using MK-specific knockout mice.The translational potential was evaluated using a human MK cell line and several pharmacological inhibitors.Results:In contrast to primitive MKs,mature MKs(mMKs)are intrinsically programmed to be apoptosis-resistant through reprogramming the Bcl-xL-BAX/BAK axis.Interestingly,mMKs undergo minority mitochondrial outer membrane permeabilization(MOMP)post IR,resulting in the activation of the cyclic GMP-AMP synthase-stimulator of IFN genes(cGAS-STING)pathway via the release of mitochondrial DNA.The subsequent interferon-β(IFN-β)response in mMKs upregulates a GTPase guanylate-binding protein 2(GBP2)to produce large and hyperreactive platelets that favor thrombosis.Further,we unmask that autophagy restrains minority MOMP in mMKs post IR.Conclusions:Our study identifies that megakaryocytic mitochondria-cGAS/STING-IFN-β-GBP2 axis serves as a fundamental checkpoint that instructs the size and function of platelets upon radiation injury and can be harnessed to treat platelet pathologies.
文摘BACKGROUND Neonatal sepsis,a formidable threat to newborns,is a leading cause of neonatal mortality,with late-onset sepsis manifesting after 72 hours post-birth being particularly concerning.Pneumonia,a prevalent sepsis presentation,poses a significant risk,especially during the neonatal phase when lung defenses are compromised.Accurate diagnosis of pneumonia is imperative for timely and effective interventions.Saliva,a minimally invasive diagnostic medium,holds great promise for evaluating infections,especially in infants.AIM To investigate the potential of serum C-reactive protein(CRP),salivary CRP(sCRP),and mean platelet volume(MPV)as diagnostic markers for late-onset neonatal pneumonia(LONP).METHODS Eighty full-term neonates were systematically examined,considering anthropometric measurements,clinical manifestations,radiology findings,and essential biomarkers,including serum CRP,sCRP,and MPV.RESULTS The study reveals noteworthy distinctions in serum CRP levels,MPV,and the serum CRP/MPV ratio between neonates with LONP and healthy controls.MPV exhibited a robust discriminatory ability[area under the curve(AUC)=0.87]with high sensitivity and specificity at a cutoff value of>8.8.Correlations between serum CRP,sCRP,and MPV were also identified.Notably,sCRP demonstrated excellent predictive value for serum CRP levels(AUC=0.89),underscoring its potential as a diagnostic tool.CONCLUSION This study underscores the diagnostic promise of salivary and serum biomarkers,specifically MPV and CRP,in identifying and predicting LONP among neonates.These findings advocate for further research to validate their clinical utility in larger neonatal cohorts.
文摘Platelet rich plasma(PRP)is an autologous blood product rich in platelets,showing promise in reducing inflammation and accelerating healing.While extensively utilized in plastic surgery,dermatology,and osteoarthritis treatment,its application in anterior cruciate ligament(ACL)injuries is limited.This article examines PRP's potential in ACL reconstruction(ACLR),exploring its history,current usage,controversies and future directions.PRP has demonstrated significant early benefits in ligamentisation and vascularisation post-ACLR,though its long-term efficacy is inconsistent.Studies suggest that PRP may serve as both an adjunct therapy in ACLR to enhance initial healing and reduce postoperative complications,and as a non-surgical alternative for small ACL tears.Despite these promising findings,outcome variability necessitates further high-quality research to optimize PRP formulations and determine its most effective applications.The exploration of PRP as a treatment modality in ACLR offers promising but varied outcomes.PRP holds considerable promise as both an adjunct and alternative to traditional ACLR.This article underscores the need for targeted research to fully realize PRP's therapeutic potential in ACL treatment,aiming to inform future studies and clinical practices.By understanding PRP's mechanisms of efficacy and identifying the most beneficial patient populations,PRP could significantly impact orthopaedics and sports medicine,improving recovery pathways and patient outcomes.
基金supported in part by Canadian Institutes of Health Research(MOP 119540),National Natural Science Foundation of China-Canadian Institutes of Health Research(China-Canada Joint Health Research Initiative Program),Heart and Stroke Foundation of Canada(Ontario)supported by equipment Funds from St.Michael's Hospital,Canadian Blood Services,and Canada Foundation for Innovation
文摘Platelets are small anucleate cells generated from megakaryocytes in the bone marrow. Although platelet genera- tion, maturation, and clearance are still not fully understood, significant progress has been made in the last 1-2 dec- ades. In blood circulation, platelets can quickly adhere and aggregate at sites of vascular injury, forming the platelet plug (i.e. the first wave of hemostasis). Activated platelets can also provide negatively charged phosphatidylserine- rich membrane surface that enhances cell-based thrombin generation, which facilitates blood coagulation (i.e. the second wave of hemostasis). Platelets therefore play central roles in hemostasis. However, the same process of hemostasis may also cause thrombosis and vessel occlusion, which are the most common mechanisms leading to heart attack and stroke following ruptured atherosclerotic lesions. In this review, we will introduce the classical mechanisms and newly discovered pathways of platelets in hemostasis and thrombosis, including fibrinogen-inde- pendent platelet aggregation and thrombosis, and the plasma fibronectin-mediated "protein wave" of hemostasis that precedes the classical first wave of hemostasis. Furthermore, we briefly discuss the roles of platelets in inflam- marion and atherosclerosis and the potential strategies to control atherothrombosis.
文摘Although viral hepatitis treatments have evolved over the years, the resultant liver cirrhosis still does not completely heal. Platelets contain proteins required for hemostasis, as well as many growth factors required for organ development, tissue regeneration and repair. Thrombocytopenia, which is frequently observed in patients with chronic liver disease(CLD) and cirrhosis, can manifest from decreased thrombopoietin production and accelerated platelet destruction caused by hypersplenism; however, the relationship between thrombocytopenia and hepatic pathogenesis, as well as the role of platelets in CLD, is poorly understood. In this paper, experimental evidence of platelets improving liver fibrosis and accelerating liver regeneration is summarized and addressed based on studies conducted in our laboratory and current progress reports from other investigators. In addition, we describe our current perspective based on the results of these studies. Platelets improve liver fibrosis by inactivating hepatic stellate cells, which decreases collagen production. The regenerative effect of platelets in the liver involves a direct effect on hepatocytes, a cooperative effect with liver sinusoidal endothelial cells, and a collaborative effect with Kupffer cells. Based on these observations, we ascertained the direct effect of platelet transfusion on improving several indicators of liver function in patients with CLD and liver cirrhosis. However, unlike the results of our previous clinical study, the smaller incremental changes in liver function in patients with CLD who received eltrombopag for 6 mo were due to patient selection from a heterogeneous population. We highlight the current knowledge concerning the role of platelets in CLD and cancer and anticipate a novel application of platelet-based clinical therapies to treat liver disease.
文摘Major depression is an independent risk factor for cardiovascular mortality and morbidity. The exact mechanisms linking depression and increased cardiovascular risk remain poorly understood. Several mechanisms have been proposed including increased platelet reactivity. This review focuses on the current literature that examines the platelet hypothesis of depression. To date studies show increased serotonin response, increased platelet serotonin receptor density, decreased serotonin transporter binding, and decreased platelet serotonin levels in individuals with depression. However other studies have shown no change in serotonin uptake. In addition to platelet serotonin specific pathways, other platelet pathways that have shown significant changes in depressed individuals include blunting of the platelet adenosine response, increased platelet thrombin response, increased glycoprotein Ⅰb expression, increased P-selectin, β thromboglobulin, and platelet factor four, as well as decreased platelet brain derived neurotrophic factor. However there are other studies that show conflicting evidence of increased platelet activation as measured by integrin receptor α2b β3. Other conflictingdata include α adrenergic density and platelet response to augmented serotonin. The direction of future research in platelet functional changes in depression and coronary artery disease should continue to focus on serotonin specific pathways with emphasis on potential mechanisms of specific pathway changes.
文摘AIM To provide a simple surrogate marker predictive of liver cirrhosis(LC).METHODS Specimens from 302 patients who underwent resection for hepatocellular carcinoma between January 2006 and December 2012 were retrospectively analyzed. Based on pathologic findings, patients were divided into groups based on whether or not they had LC. Parameters associated with hepatic functional reserve were compared in these two groups using MannWhitney U-test for univariate analysis. Factors differing significantly in univariate analyses were entered into multivariate logistic regression analysis.RESULTS There were significant differences between the LC group(n = 100) and non-LC group(n = 202) in prothrombin activity, concentrations of alanine aminotransferase, aspartate aminotransferase, total bilirubin, albumin, cholinesterase, type Ⅳ collagen, hyaluronic acid, indocyanine green retention rate at 15 min, maximal removal rate of technitium-99 m diethylene triamine pentaacetic acid-galactosyl human serum albumin and ratio of mean platelet volume to platelet count(MPV/PLT). Multivariate analysis showed that prothrombin activity, concentrations of alanine aminotransferase, aspartate aminotransferase, total bilirubin and hyaluronic acid, and MPV/PLT ratio were factors independently predictive of LC. The area under the curve value for MPV/PLT was 0.78,with a 0.8 cutoff value having a sensitivity of 65% and a specificity of 78%.CONCLUSION The MPV/PLT ratio, which can be determined simply from the complete blood count, may be a simple surrogate marker predicting LC.
基金Supported by Research grants from University of Tsukubathe Basic Research Support Program for Young Researcher
文摘AIM:To investigate the role of human platelets in liver fibrosis.METHODS:Severe combined immunodeficiency(SCID)mice were administered CCl4and either phosphate-buffered saline(PBS group)or human platelet transfusions(hPLT group).Concentrations of hepatocyte growth factor(HGF),matrix metallopeptidases(MMP)-9,and transforming growth factor-β(TGF-β)in the liver tissue were compared between the PBS and the hPLT groups by enzyme-linked immunosorbent assay(ELISA)and Western blotting.The effects of a human platelet transfusion on liver fibrosis included the fibrotic area,hydroxyproline content,and-smooth muscle actin(α-SMA)expression,which were evaluated by picrosirius red staining,ELISA,and immunohistochemical staining using an anti-mouse-SMA antibody,respectively.Phosphorylations of mesenchymal-epithelial transition factor(Met)and SMAD3,downstream signals of HGF and TGF-β,were compared between the two groups by Western blotting and were quantified using densitometry.Hepatocyte apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling.Furthermore,the accumulation of human platelets in the liver 2 h after platelet transfusion was compared between normal and fibrotic livers by immunohistochemical staining using an anti-human CD41 antibody.RESULTS:The fibrotic area and hydroxyproline content in the liver were both significantly lower in the hPLT group when compared to the PBS group(fibrotic area,1.7%±0.6%vs 2.5%±0.6%,P=0.03;hydroxyproline content,121±26 ng/g liver vs 156±47 ng/g liver,P=0.04).There was less α-smooth muscle actin staining in the hPLT group than in the PBS group(0.5%±0.1%vs 0.8%±0.3%,P=0.02).Hepatic expression levels of mouse HGF and MMP-9were significantly higher in the hPLT group than in the PBS group(HGF,109±13 ng/g liver vs 88±22 ng/g liver,P=0.03;MMP-9,113%±7%/GAPDH vs 92%±11%/GAPDH,P=0.04).In contrast,the concentration of mouse TGF-β in the liver tissue was significantly lower in the hPLT group than in the PBS group(22±5ng/g liver vs 39±6 ng/g liver,P=0.02).Phosphorylation of Met was more prevalent in the hPLT group than in the PBS group(37%±4%/GAPDH vs 20%±8%/GAPDH,P=0.03).Phosphorylation of SMAD3was weaker in the hPLT group than in the PBS group(60%±12%/GAPDH vs 84%±12%/GAPDH,P=0.1),although this difference was not significant.Furthermore,a lower rate of hepatocyte apoptosis was observed in the hPLT group than in the PBS group(5.9%±1.7%vs 2.9%±2.1%,P=0.02).Significant human platelet accumulation was observed in the fibrotic liver tissues,whereas few platelets accumulated in the normal liver.CONCLUSION:Human platelets inhibit liver fibrosis in SCID mice.Increased concentration of HGF in the liver suppresses hepatic stellate cell activation,induces MMPs,and inhibits hepatocyte apoptosis.
基金Supported by the Joint Foundation of Department of Science and Technology of Guizhou Province,China,No.[2016]7408
文摘AIM To investigate serum mean platelet volume(MPV) levels in acute pancreatitis(AP) patients and assess whether MPV effectively predicts the disease severity of AP.METHODS We included 117 consecutive patients with AP as the AP group and 34 consecutive patients with colorectal polyps(before endoscopic treatment) as the control group. Complete blood counts, liver function, platelet indices(MPV), coagulation parameters, lactate dehydrogenase(LDH) and C-reactive protein(CRP) were measured on days 1, 2, 3 and 7 after admission. Receiver operating characteristic curves were used to compare the sensitivity and specificity of MPV, white blood cell(WBC), LDH and CRP in predicting AP severity. The Modified Glasgow Prognostic Score(m GPS) and the 2012 revised Atlanta criteria were used to evaluate disease severity in AP.RESULTS MPV levels were significantly lower in the AP group than in the control group on day 1(P = 0.000), day 2(P = 0.029) and day 3(P = 0.001) after admission.In addition, MPV values were lower on day 1 after admission than on day 2(P = 0.012), day 3(P = 0.000) and day 7(P = 0.002) in all AP patients. Based on the m GPS, 78 patients(66.7%) were diagnosed with mild and 39 patients(33.3%) with severe AP. There was no significant difference in mean MPV levels between patients diagnosed with mild and severe AP based on the m GPS(P = 0.424). According to the 2012 revised Atlanta criteria, there were 98 patients(83.8%) without persistent organ failure(OF) [non-severe acute pancreatitis(non-SAP) group] and 19 patients(16.2%) with persistent OF(SAP group). MPV levels were significantly lower in the SAP group than in the non-SAP group on day 1 after admission(P = 0.002). On day 1 after admission using a cut-off value of 6.65 f L, the overall accuracy of MPV for predicting SAP according to the 2012 revised Atlanta criteria(AUC = 0.716) had a sensitivity of 91.8% and a specificity of 47.4% and was superior to the accuracy of the traditional markers WBC(AUC = 0.700) and LDH(AUC = 0.697).CONCLUSION MPV can be used at no additional cost as a useful, noninvasive biomarker that distinguishes AP with persistent OF from AP without persistent OF on day 1 of hospital admission.
文摘There is evidence that inflammatory bowel diseases (IBD) combine both inflammation and coagulation in their pathogenesis and clinical manifestations. Although platelets (PLT) are well known for their role in hemostasis, there are a rising number of studies supporting their considerable role as inflammatory amplifiers in chronic inflammatory conditions. IBD are associated with several alterations of PLT, including number, shape, and function, and these abnormalities are mainly attributed to the highly activated state of circulating PLT in IBD patients. When PLT activate, they increase in size, release a great variety of bio-active inflammatory and procoagulant molecules/particles, and express a variety of inflammatory receptors. These inflammatory products may represent a part of the missing link between coagulation and inflammation, and can be considered as possible IBD pathogenesis instigators. In clinical practice, thrombocytosis is associated both with disease activity and iron deficiency anemia. Controlling inflammation and iron replacement in anemic patients usually leads to a normalization of PLT count. The aim of this review is to update the role of PLT in IBD and present recent data revealing the possible therapeutic implications of anti-PLT agents in future IBD remedies.
基金Supported by The Ministry of Education, Culture, Sports, Science, and Technology of Japan, KAKENHI, No. 22591499
文摘AIM: To investigate the effect of mild steatotic liver on ischemia-reperfusion injury by focusing on Kupffer cells (KCs) and platelets. METHODS: Wistar rats were divided into a normal liver group (N group) and a mild steatotic liver group (S group) induced by feeding a choline-deficient diet for 2 wk. Both groups were subjected to 20 min of warm ischemia followed by 120 min of reperfusion. The number of labeled KCs and platelets in sinusoids and the blood perfusion in sinusoids were observed by intravital microscopy (IVM), which was performed at 30, 60 and 120 min after reperfusion. To evaluate serum alanine aminotransferase as a marker of liver deterioration, blood samples were taken at the same time as IVM.RESULTS: In the S group, the number of platelets adhering to KCs decreased significantly compared with the N group (120 after reperfusion; 2.9±1.1 cells/acinus vs 4.8±1.2 cells/acinus, P<0.01). The number of KCs in sinusoids was significantly less in the S group than in the N group throughout the observation periods (before ischemia, 19.6±3.3 cells/acinus vs 28.2±4.1 cells/acinus, P<0.01 and 120 min after reperfusion, 29.0±4.3 cells/acinus vs 40.2±3.3 cells/acinus, P<0.01). The blood perfusion of sinusoids 120 min after reperfusion was maintained in the S group more than in the N group. Furthermore, elevation of serum alanine aminotransferase was lower in the S group than in the N group 120 min after reperfusion (99.7±19.8 IU/L vs 166.3±61.1 IU/L, P=0.041), and histological impairment of hepatocyte structure was prevented in the S group. CONCLUSION: Ischemia-reperfusion injury in mild steatotic liver was attenuated compared with normal liver due to the decreased number of KCs and the reduction of the KC-platelet interaction.
基金Project(2008A090300016) supported by the Key Science and Technology Item of Guangdong Province,ChinaProject(ZKJ2010022) supported by the Precious Apparatus Opening Center Foundation of Central South University,China
文摘Well-crystallized hexagonal hematite (α-Fe2O3) platelets were synthesized by hydrothermal process, using a highly concentrated ferric hydroxide as precursor. The precursor was prepared by adding ammonia to the ferric sulfate solution which was obtained by leaching pyrite cinders with sulfuric acid. Structure and morphology of the synthesized products were investigated by X-ray diffraction, scanning electron microscope, transmission electron microscope and selected area electron diffraction. The results reveal that the reaction temperature has significant effects on the structure, size and shape of the synthesized hematite particles. Typical hexagonal hematite platelets, about 0.4-0.6 μm in diameter and 0.1 μm in thickness, were prepared at 230 ℃ for 0.5 h. Al^3+, contained in the sulfuric acid leaching solution as an impurity, plays an extremely important role in the formation of hexagonal hematite. In addition, a possible mechanism about the formation of hexagonal hematite platelets was proposed.
文摘The thermal vibration of functionally graded(FG)porous nanocomposite beams reinforced by graphene platelets(GPLs)is studied.The beams are exposed to the thermal gradient with a multilayer structure.The temperature varies linearly across the thickness direction.Three different types of dispersion patterns of GPLs as well as porosity distributions are presented.The material properties vary along the thickness direction.By using the mechanical parameters of closed-cell cellular solid,the variation of Poisson’s ratio and the relation between the porosity coefficient and the mass density under the Gaussian random field(GRF)model are obtained.By using the Halpin-Tsai micromechanics model,the elastic modulus of the nanocomposite is achieved.The equations of motion based on the Timoshenko beam theory are obtained by using Hamilton’s principle.These equations are discretized and solved by using the generalized differential quadrature method(GDQM)to obtain the fundamental frequencies.The effects of the weight fraction,the dispersion model,the geometry,and the size of GPLs,as well as the porosity distribution,the porosity coefficient,the boundary condition,the metal matrix,the slenderness ratio,and the thermal gradient are presented.
文摘The effects of different additives on the mechanical properties, microstructures, and wear behavior of corundum abra- sives were investigated. When the number of additive phases increases, the sintering temperature and wear rate decrease, while the densification and mechanical properties increase. The additive SiO2 is responsible for the development of equiaxed grains, whereas both CaO and MgO promote the development of platelike grains. By controlling the molar ratio of additives, it is pos- sible to obtain different microstructures. With SiO2-MgO-CaO (molar ratio, 2:1:1) as the additives and nano a-Al203 powders as the seed, microcrystalline corundum abrasives with hexagonal platelets were obtained using sol-gel process by sintering at 1300℃ for 0.5 h. The average diameter and thickness of hexagonal platelets are 1.38 μm and 360 nm respectively, the sin- gle-particle compressive strength is 26.44 N, and the wear rate is (3.06±=0.21)× 10^-7 mm^3/(N.m).
基金supported by grants from the Natural Science Foundation of Zhejiang Province(Y17H160118,LY18H030002 and LQ15H030003)the Fundamental Research Funds for the Cen-tral University(2018FZA7002)
文摘Background: Lower mean platelet volume(MPV) is an indicator of platelet activity in the setting of tumor development. This study was to assess the relationship between preoperative MPV and survival outcomes of patients with hepatocellular carcinoma(HCC) following liver transplantation(LT). Methods: The demographic and clinical characteristics of 304 HCC patients following LT were retrieved from an LT database. All the patients were divided into the normal and lower MPV groups according to the median MPV. The factors were first analyzed using a Kaplan–Meier survival analysis, then the factors with P < 0.10 were selected for multivariate Cox regression analysis and were used to define the independent risk factors for poor prognosis. Results: The 1-, 3-, and 5-year tumor free survival was 95.34%, 74.67% and 69.29% in the normal MPV group, respectively, and 95.40%, 59.97% and 42.94% in the lower MPV group, respectively( P < 0.01). No significant difference was observed in post-LT complications between the normal and lower MPV groups. Portal vein tumor thrombosis(PVTT)[hazard ratio(HR = 2.24;95% confidence interval: 1.46–3.43;P < 0.01) and lower MPV(HR = 1.58;95% confidence interval: 1.05–2.36;P = 0.03) were identified as independent prognostic risk factors for recipient survival. Conclusion: Preoperative lower MPV is a risk indicator of HCC patients survival outcomes after LT.
文摘The high mortality rate of breast cancer is mainly caused by the metastatic ability of cancer cells,resistance to chemotherapy and radiotherapy,and tumor regression capacity.In recent years,it has been shown that the presence of breast cancer stem cells is closely associated with the migration and metastatic ability of cancer cells,as well as with their resistance to chemotherapy and radiotherapy.The tumor microenvironment is one of the main molecular factors involved in cancer and metastatic processes development,in this sense it is interesting to study the role of platelets,one of the main communicator cells in the human body which are activated by the signals they receive from the microenvironment and can generate more than one response.Platelets can ingest and release RNA,proteins,cytokines and growth factors.After the platelets interact with the tumor microenvironment,they are called"tumor-educated platelets."Tumor-educated platelets transport material from the tumor microenvironment to sites adjacent to the tumor,thus helping to create microenvironments conducive for the development of primary and metastatic tumors.It has been observed that the clone capable of carrying out the metastatic process is a cancer cell with stem cell characteristics.Cancer stem cells go through a series of processes,including epithelial-mesenchymal transition,intravasation into blood vessels,movement through blood vessels,extravasation at the site of the establishment of a metastatic focus,and site colonization.Tumor-educated platelets support all these processes.
基金Supported by National Natural Science Foundation of China,No.U1301227,No.81872032 and No.U1804262Doctoral Team Foundation of the First Affiliated Hospital of Zhengzhou University,No.2016-BSTDJJ-03.
文摘BACKGROUND Preoperative pulmonary function plays an important role in selecting surgical candidates and assessing postoperative complications.Reduced pulmonary function is associated with poor survival in several cancers,but the prognostic value of preoperative pulmonary function in esophageal squamous cell carcinoma(ESCC)is unclear.Nutritional and systemic inflammation parameters are vital to cancer survival,and the combination of these parameters improves the prognostic value.The hemoglobin,albumin,lymphocytes and platelets(HALP)score is a novel prognostic indicator to reflect the nutritional and inflammation status,but the clinical effects of the HALP score combined with maximal voluntary ventilation(MVV),an important parameter of pulmonary function,have not been well studied in ESCC.AIM To investigate the prognostic value of MVV and HALP score for assessing postoperative survival of ESCC patients.METHODS Data form 834 ESCC patients who underwent radical esophagectomy with R0 resection were collected and retrospectively analyzed.Preoperative MVV and HALP data were retrieved from medical archives.The HALP score was calculated by the formula:Hemoglobin(g/L)×albumin(g/L)×lymphocytes(/L)/platelets(/L).The optimal cut-off values of MVV and HALP score were calculated by the receiver operating characteristic curve analysis.The Kaplan-Meier method with log-rank test was used to draw the survival curves for the variables tested.Multivariate Cox proportional hazard regression models were used to analyze the independent prognostic factors for overall survival.RESULTS MVV was significantly associated with gender(P<0.001),age at diagnosis(P<0.001),smoking history(P<0.001),drinking history(P<0.001),tumor length(P=0.013),tumor location(P=0.037)and treatment type(P=0.001).The HALP score was notably associated with gender(P<0.001),age at diagnosis(P=0.035),tumor length(P<0.001)and invasion depth(P=0.001).Univariate Cox regression analysis showed that low MVV and low HALP score were associated with worse overall survival(all P<0.001).Multivariate analysis showed that low MVV and the HALP score were both independent risk factors for overall survival(all P<0.001).The combination of MVV and HALP score improved the prediction performance for overall survival than tumor-node-metastasis.Also,low combination of MVV and HALP score was an independent risk factor for poor overall survival(P<0.001).CONCLUSION MVV,HALP score and their combination are simple and promising clinical markers to predict overall survival of ESCC patients.
基金supported by grants from the National Natural Science Foundation of China(No. 81300347)the Natural Science Foundation of Jiangxi Province,China(No.20132BAB205037,20151BAB215008, 20151BBG70200)+1 种基金Foundation of Jiangxi Educational Committee(No.GJJ14192)Foundation of Health and Family Planning Commission of Jiangxi Province(No. 20155592,20155103)
文摘Metastasis is the main cause of cancer-associated mortality. During this complicated process, some cancer cells, also called circulating tumor cells (CTCs), detach from primary sites, enter bloodstream and extravasate at metastatic site. Thrombocytosis is frequently observed in patients with metastatic cancers suggesting the important role of platelets in metastasis. Therefore this review focuses on how platelets facilitate the generation of CTCs, protect them from various host attacks, such as immune assaults, apoptosis and shear stress, and regulate CTCs intravasation/extravasation. Platelet-derived cytokines and receptors are involved in this cascade. Identification the mechanisms underlie platelet-CTCs interactions could lead to the development of new platelet-targeted therapeutic strategy to reduce metastasis.
基金This work was supported by the National Natural Science Foundation of China (No. 81500109).
文摘Mean platelet volume (MPV) is an early marker ofplatelet activation. Larger platelets, compared to small ones, increase platelet adhesion and aggregation, and present a higher thrombotic activity. Some studies have explored the association between MPV and the morbidity of portal vein thrombosis (PVT). The aim of this study was to evaluate the predictive effect of MPV in patients with PVT by a meta-analysis. We searched Pubmed, Web of Science, SCOPUS, OVID, CNKI and CBMD from database inception to September 13, 2017. Seven studies in accordance with selection criteria were included. The extraction of basic data was independently conducted by two reviewers. The mean difference in MPV between PVT patients and controls were pooled with weighted mean difference (WMD) and 95% confidence interval of 0.88 fl (95% CI: 0.61-1.15). A random-effect model was chosen for an obvious heterogeneity in the pooling (Chi-square=27.12, df=6, P〈0.0001, F=77.9%). The sources of heterogeneity were from the difference of primary disease of participants and portal vein diameter. Taken together, our results reveal that MPV is a predictive indicator in patients with PVT.
基金financial support by the Australian Research Council (LP180100005 & DP200101737)。
文摘Featuring exceptional mechanical and functional performance, MWCNTs and graphene(nano)platelets(GNPs or Gn Ps;each platelet below 10 nm in thickness) have been increasingly used for the development of polymer nanocomposites. Since MWCNTs are now cost-effective at US$30 per kg for industrial applications, this work starts by briefly reviewing the disentanglement and surface modification of MWCNTs as well as the properties of the resulting polymer nanocomposites. GNPs can be made through the thermal treatment of graphite intercalation compounds followed by ultrasonication;GNPs would have lower cost yet higher electrical conductivity over 1,400 S cmthan MWCNTs. Through proper surface modification and compounding techniques, both types of fillers can reinforce or toughen polymers and simultaneously add anti-static performance. A high ratio of MWCNTs to GNPs would increase the synergy for polymers. Green, solvent-free systhesis methods are desired for polymer nanocomposites. Perspectives on the limitations, current challenges and future prospects are provided.