Background:Cytomegalovirus(CMV)reactivation is linked to a high mortality rate,especially among the elderly.Prior research suggests that renin-angiotensin system(RAS)inhibitors may influence both the onset and prognos...Background:Cytomegalovirus(CMV)reactivation is linked to a high mortality rate,especially among the elderly.Prior research suggests that renin-angiotensin system(RAS)inhibitors may influence both the onset and prognosis of pneumonia.This study aims to examine the causal relationship between RAS inhibitor use and the risk of CMV pneumonia using Mendelian randomization(MR)analysis.Methods:We conducted an analysis using data from two genome-wide association studies(GWAS)involving individuals of European ancestry.This dataset included individuals treated with RAS inhibitors and those with CMV pneumonia.We assessed the relationship between RAS inhibitor use and CMV pneumonia risk using the inverse variance weighted(IVW)method.The results were further evaluated for pleiotropy,heterogeneity,and robustness.Results:The Mendelian randomization(MR)analysis revealed a causal relationship between RAS inhibitor use and an increased risk of CMV pneumonia(IVW:odds ratio[OR]=2.73;95%confidence interval[CI]=1.11-6.73;P=0.028).Conclusions:Our finding indicate a positive causal relationship between the use of RAS inhibitors and the onset of CMV pneumonia.展开更多
AIM: To observe changes of mitochondria and investigate the effect of ethanol on mitochondrial perme- ability transition pore (PTP), mitochondrial membrane potential (MMP, ΔΨm) and intracellular calcium concentratio...AIM: To observe changes of mitochondria and investigate the effect of ethanol on mitochondrial perme- ability transition pore (PTP), mitochondrial membrane potential (MMP, ΔΨm) and intracellular calcium concentration in hepatocytes by establishing an animal model of alcoholic liver disease (ALD). METHODS: Fourty adult male Wistar rats were randomly divided into two groups, the model group (20) was administered alcohol intragastrically plus an Oliver oil diet to establish an ALD model, and the control group (20) was given an equal amount of normal saline. The ultramicrostructural changes of mitochondria were observed under electron microscopy. Mitochondria of liver was extracted, and patency of PTP, mitochondrial membrane potential (ΔΨm), mitochondrial mass and intracellular calcium concentration of isolated hepacytes were detected by flow cytometry using rhodamine123 (Rh123), Nonyl-Acridine Orange and calcium fluorescent probe Fluo-3/AM, respectively. RESULTS: Membrane and cristae were broken or disappeared in mitochondria in different shapes under electron microscopy. Some mitochondria showed U shape or megamitochondrion. In the model group, liver mitochondria PTP was broken, and mitochondria swelled, the absorbance at 450 nm, A540 decreased (0.0136 ± 0.0025 vs 0.0321 ± 0.0013, model vs control, P < 0.01); mitochondria transmembrane potential (239.4638 ± 12.7263 vs 377.5850 ± 16.8119, P < 0.01) was lowered; mitochondrial mass (17.4350 ± 1.9880 vs 31.6738 ± 3.4930, P < 0.01); and [Ca2+]i was increased in liver cells (7.0020 ± 0.5008 vs 10.2050 ± 0.4701, P < 0.01).CONCLUSION: Chronic alcohol intake might lead to broken mitochondria PTP, decreased mitochondria membrane potential and injury, and elevated intracellular Ca2+ production. Ethanol-induced chondriosome injury may be an important mechanism of alcoholic diseases.展开更多
The core-shell 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/2,4,6-Trinitrotoluene(CL-20/TNT)composite was prepared by spray-drying method in which sensitive high energy explosive(CL-20)was coated with in...The core-shell 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/2,4,6-Trinitrotoluene(CL-20/TNT)composite was prepared by spray-drying method in which sensitive high energy explosive(CL-20)was coated with insensitive explosive(TNT).The structure and properties of different formulations of CL-20/TNT composite and CL-20/TNT mixture were characterized by scanning electron microscopy(SEM),Transmission electron microscopy(TEM),Laser particle size analyzer,X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD),differential scanning calorimetry(DSC),impact sensitivity test and detonation performance.The results of SEM,TEM,XPS and XRD show that e-CL-20 particles are coated by TNT.When the ratio of CL-20/TNT is 75/25,core-shell structure is well formed,and thickness of the shell is about 20e30 nm.And the analysis of heat and impact show that with the increase of TNT content,the TNT coating on the core-shell composite material can not only catalyze the thermal decomposition of core material(CL-20),but also greatly reduce the impact sensitivity.Compared with the CL-20/TNT mixture(75/25)at the same ratio,the characteristic drop height of core-shell CL-20/TNT composite(75/25)increased by 47.6%and the TNT coating can accelerate the nuclear decomposition in the CL-20/TNT composites.Therefore,the preparation of the core-shell composites can be regarded as a unique means,by which the composites are characterized by controllable decomposition rate,high energy and excellent mechanical sensitivity and could be applied to propellants and other fields.展开更多
Hexagonal boron nitride nanosheets(HBNNSs)have huge potential in the field of coating materials owing to their remarkable chemical stability,mechanical strength and thermal conductivity.Thin-layer hBNNSs were obtained...Hexagonal boron nitride nanosheets(HBNNSs)have huge potential in the field of coating materials owing to their remarkable chemical stability,mechanical strength and thermal conductivity.Thin-layer hBNNSs were obtained by a liquid-phase exfoliation of h-BN powders and incorporated into EVA coatings for improving the safety performance of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX).HBNNSs and ethylene-vinyl acetate copolymer(EVA)were introduced to HMX by a solvent-slurry process.For comparison,the HMX/EVA and HMX/EVA/graphene(HMX/EVA/G)composites were also prepared by a similar process.The morphology,crystal form,surface element distribution,thermal decomposition property and impact sensitivity of HMX/EVA/hBNNSs composites were contrastively investigated.Results showed that as prepared HMX/EVA/hBNNSs composites were well coated with hBNNSs and EVA,and exhibited better thermal stability and lower impact sensitivity than that of HMX/EVA and HMX/EVA/G composites,suggesting superior performance of desensitization of hBNNSs in explosives.展开更多
AIM: To establish a clinical scoring model to predict risk of acute-on-chronic liver failure(ACLF) in chronic hepatitis B(CHB) patients.METHODS: This was a retrospective study of 1457 patients hospitalized for CHB bet...AIM: To establish a clinical scoring model to predict risk of acute-on-chronic liver failure(ACLF) in chronic hepatitis B(CHB) patients.METHODS: This was a retrospective study of 1457 patients hospitalized for CHB between October 2008 and October 2013 at the Beijing Ditan Hospital, Capital Medical University, China. The patients were divided into two groups: severe acute exacerbation(SAE) group(n = 382) and non-SAE group(n = 1075). The SAE group was classified as the high-risk group based on the higher incidence of ACLF in this group than in the non-SAE group(13.6% vs 0.4%). Two-thirds of SAE patients were randomly assigned to risk-model derivation and the other one-third to model validation. Univariate risk factors associated with the outcome were entered into a multivariate logistic regression model for screening independent risk factors. Each variable was assigned an integer value based on the regression coefficients, and the final score was the sum of these values in the derivation set. Model discrimination and calibration were assessed using area under the receiver operating characteristic curve and the Hosmer-Lemeshow test. RESULTS: The risk prediction scoring model includedthe following four factors: age ≥ 40 years, total bilirubin ≥ 171 μmol/L, prothrombin activity 40%-60%, and hepatitis B virus DNA > 107 copies/m L. The sum risk score ranged from 0 to 7; 0-3 identified patients with lower risk of ACLF, whereas 4-7 identified patients with higher risk. The Kaplan-Meier analysis showed the cumulative risk for ACLF and ACLF-related death in the two risk groups(0-3 and 4-7 scores) of the primary cohort over 56 d, and log-rank test revealed a significant difference(2.0% vs 33.8% and 0.8% vs 9.4%, respectively; both P < 0.0001). In the derivation and validation data sets, the model had good discrimination(C index = 0.857, 95% confidence interval: 0.800-0.913 and C index = 0.889, 95% confidence interval: 0.820-0.957, respectively) and calibration demonstrated by the Hosmer-Lemeshow test(χ2 = 4.516, P = 0.808 and χ2 = 1.959, P = 0.923, respectively).CONCLUSION: Using the scoring model, clinicians can easily identify patients(total score ≥ 4) at high risk of ACLF and ACLF-related death early during SAE.展开更多
Objective To examine whether ischemic preconditioning (IPC) can protect neuron against delayed death in CA1 subfield of hippocampus following reperfusion of a lethal ischemia in rats, and explore the role of p53 and b...Objective To examine whether ischemic preconditioning (IPC) can protect neuron against delayed death in CA1 subfield of hippocampus following reperfusion of a lethal ischemia in rats, and explore the role of p53 and bax in this process. Methods We examined the effect of IPC on delayed neuron death, neuron apoptosis, expressions of p53 and bax gene in the CA1 area of hippocampus in the rats using HE staining, flow cytometry, RT-PCR, and immunohistochemistry technique. Results IPC enhanced the quantity of survival cells in the CA1 region of hippocampus (216±9 cells/0.72 mm2 vs. 30±5 cells/0.72 mm2, P<0.01), decreased the percentages of apoptotic neurons of hippocampus caused by ischemia/reperfusion (2.06%±0.21% vs. 4.27%±0.08%, P<0.01), and weakened the expressions of p53 and bax gene of hippocampus compared with ischemia/reperfusion without IPC. Conclusion IPC can protect the neurons in the CA1 region of hippocampus against apoptosis caused by ische- mia/reperfusion, and this process may be related to the reduced expressions of p53 and bax.展开更多
AIM: To investigate the regulatory effect of Vδ1 T cells and the antitumor activity of Vδ2 T cells in rectal cancer.METHODS: Peripheral blood, tumor tissues and para-carcinoma tissues from 20 r...AIM: To investigate the regulatory effect of Vδ1 T cells and the antitumor activity of Vδ2 T cells in rectal cancer.METHODS: Peripheral blood, tumor tissues and para-carcinoma tissues from 20 rectal cancer patients were collected. Naïve CD4 T cells from the peripheral blood of rectal cancer patients were purified by negative selection using a Naive CD4<sup>+</sup> T Cell Isolation Kit II (Miltenyi Biotec). Tumor tissues and para-carcinoma tissues were minced into small pieces and digested in a triple enzyme mixture containing collagenase type IV, hyaluronidase, and deoxyribonuclease for 2 h at room temperature. After digestion, the cells were washed twice in RPMI1640 and cultured in RPMI1640 containing 10% human serum supplemented with L-glutamine and 2-mercaptoethanol and 1000 U/mL of IL-2 for the generation of T cells. Vδ1 T cells and Vδ2 T cells from tumor tissues and para-carcinoma tissues were expanded by anti-TCR γδ antibodies. The inhibitory effects of Vδ1 T cells on naïve CD4 T cells were analyzed using the CFSE method. The cytotoxicity of Vδ2 T cells on rectal cancer lines was determined by the LDH method.RESULTS: The percentage of Vδ1 T cells in rectal tumor tissues from rectal cancer patients was significantly increased, and positively correlated with the T stage. The percentage of Vδ2 T cells in rectal tumor tissues from rectal cancer patients was significantly decreased, and negatively correlated with the T stage. After culture for 14 d with 1 μg/mL anti-TCR γδ antibodies, the percentage of Vδ1 T cells from para-carcinoma tissues was 21.45% ± 4.64%, and the percentage of Vδ2 T cells was 38.64% ± 8.05%. After culture for 14 d, the percentage of Vδ1 T cells from rectal cancer tissues was 67.45% ± 11.75% and the percentage of Vδ2 T cells was 8.94% ± 2.85%. Tumor-infiltrating Vδ1 T cells had strong inhibitory effects, and tumor-infiltrating Vδ2 T cells showed strong cytolytic activity. The inhibitory effects of Vδ1 T cells from para-carcinoma tissues and from rectal cancer tissue were not significantly different. In addition, the cytolytic activities of Vδ2 T cells from para-carcinoma tissues and from rectal cancer tissues were not significantly different.CONCLUSION: A percentage imbalance in Vδ1 and Vδ2 T cells in rectal cancer patients may contribute to the development of rectal cancer.展开更多
Shale oil formations contain both inorganic and organic media.The organic matter holds both free oil in the pores and dissolved oil within the kerogen molecules.The free oil flow in organic pores and the dissolved oil...Shale oil formations contain both inorganic and organic media.The organic matter holds both free oil in the pores and dissolved oil within the kerogen molecules.The free oil flow in organic pores and the dissolved oil diffusion in kerogen molecules are coupled together.The molecular flow of free n-alkanes is an important process of shale oil accumulation and production.To study the dynamics of imbibition process of n-alkane molecules into kerogen slits,molecular dynamics(MD)simulations are conducted.Effects of slit width,temperature,and n-alkane types on the penetration speed,dynamic contact angle,and molecular conformations were analyzed.Results showed that molecular transportation of n-alkanes is dominated by molecular structure and molecular motion at this scale.The space-confinement conformational changes of molecules slow down the filling speeds in the narrow slits.The n-alkane molecules with long carbon chains require more time to undergo conformational changes.The high content of short-chain alkanes and high temperature facilitate the flow of alkane mixtures in kerogen slits.Results obtained from this study are useful for understanding the underlying nanoscale flow mechanism in shale formations.展开更多
The research on electrocatalysts with relatively lower price than Pt and excellent electrocatalytic performance for the cathode oxygen reduction reaction(ORR) and anode methanol oxidation reaction(MOR) is vital for th...The research on electrocatalysts with relatively lower price than Pt and excellent electrocatalytic performance for the cathode oxygen reduction reaction(ORR) and anode methanol oxidation reaction(MOR) is vital for the development of direct methanol fuel cells(DMFCs). In this work, we develop a cyanogel-reduction method to synthesize reduced graphene oxide(rGO) supported highly dispersed PdNi alloy nanocrystals(PdNi/rGO) with high alloying degree and tunable Pd/Ni ratio. The large specific surface area and the d-band center downshift of Pd result in excellent activity of Pd4 Ni1/rGO nanohybrids for the ORR. The modification of Pd electronic structure can facilitate the adsorption of CH3 OH on Pd surface and the highly oxophilic property of Ni can eliminate/mitigate the COadsintermediates poisoning, which make PdNi/r GO nanohybrids possess superior MOR activity. In addition, rGO improve the stability of PdNi alloy nanocrystals for the ORR and MOR. Due to high activity and stability for the ORR and MOR, PdNi/rGO nanohybrids are promising to be an available bifunctional electrocatalyst in DMFCs.展开更多
BACKGROUND Porphyria is a rare disease with complex classification. Erythropoietic protoporphyria(EPP) is an autosomal recessively inherited disease, and most are caused by mutations in the FECH gene. EPP combined wit...BACKGROUND Porphyria is a rare disease with complex classification. Erythropoietic protoporphyria(EPP) is an autosomal recessively inherited disease, and most are caused by mutations in the FECH gene. EPP combined with liver injury is even rarer.CASE SUMMARY This paper reports a case of EPP which was admitted to the hospital with abnormal liver function and diagnosed by repeated questioning of medical history, screening of common causes of severe liver injury, and second generation sequencing of the whole exon genome. We also summarize the clinical characteristics of EPP with liver injury, and put forward some suggestions on EPP to provide a reference for the diagnosis of such rare disease.CONCLUSION A new mutation locus(c.32_35 dupCCCT) which may be related to the disease was found by detecting the FECH gene in the pedigree of this case.展开更多
Microscopic seepage characteristics are critical for the evaluation of tight sandstone reservoirs.In this study,a digital core approach integrating microscopic seepage simulation and CT scanning was developed to chara...Microscopic seepage characteristics are critical for the evaluation of tight sandstone reservoirs.In this study,a digital core approach integrating microscopic seepage simulation and CT scanning was developed to characterize microscopic seepage and fracture effectiveness(the ratio of micro-fractures that contributes to fluid flow)of tight sandstones.Numerical simulations were carried out for characterizations of tight sandstones.The results show that the axial permeability of the investigated cylindrical tight sandstone from Junggar Basin in China is 0.460μm~2,while the radial permeability is 0.3723μm~2,and the axial and radial effective fracture ratios are 0.4387 and 0.4806,respectively,indicating that cracks are not fully developed and the connectivity between micro-cracks is poor.Directional permeability that is difficult to measure by laboratory experiments can be obtained readily using the proposed method in this paper.The results provide important information for improving the exploration and development of tight sandstone reservoirs.展开更多
BACKGROUND Mammary analogue secretory carcinoma(MASC)is a rare low-grade malignant salivary gland tumor.The morphological and immunohistochemical features of MASC closely resemble those of breast secretory carcinoma.T...BACKGROUND Mammary analogue secretory carcinoma(MASC)is a rare low-grade malignant salivary gland tumor.The morphological and immunohistochemical features of MASC closely resemble those of breast secretory carcinoma.The key characteristics of the lesion are a lack of pain and slow growth.There is no obvious specificity in the clinical manifestations and imaging features.The diagnosis of the disease mainly depends on the detection of the MASC-specific ETV6-NTRK3 fusion gene.CASE SUMMARY This report describes a rare case of a 32-year-old male patient who presented with a gradually growing lesion that was initially diagnosed as breast-like secretory carcinoma of the right parotid gland.Imaging and histological investigations were used to overcome the diagnostic difficulties.The lesion was managed with right parotidectomy,facial nerve preservation,biological patch implantation to restore the resulting defect,and postoperative radiotherapy.On postoperative follow-up,the patient reported a mild facial deformity with no complications,signs of facial paralysis,or Frey’s syndrome.CONCLUSION The imaging and histological diagnostic challenges for MASC are discussed.展开更多
Oxidative dehydrogenation of propane is an attractive route for the synthesis of propylene due to its favorable thermodynamic and kinetic characteristics, however, it is challenging to realize high selectivity towards...Oxidative dehydrogenation of propane is an attractive route for the synthesis of propylene due to its favorable thermodynamic and kinetic characteristics, however, it is challenging to realize high selectivity towards propylene. Recently, it has been discovered that boron nitride (BN) is a promising catalyst that affords superior selectivity towards propylene in oxidative dehydrogenation of propane. Summarizing the progress and unravelling the reaction mechanism of BN in oxidative dehydrogenation of propane are of great significance for the rational design of efficient catalysts in the future. Herein, in this review, the underlying reaction mechanisms of oxidative dehydrogenation of propane over BN are extracted;the developed BN catalysts are classified into pristine BN, functionalized BN, supported BN and others, and the applications of each category of BN catalysts in oxidative dehydrogenation of propane are summarized;the challenges and opportunities on oxidative dehydrogenation of propane over BN are pointed out, aiming to inspire more studies and advance this research field.展开更多
Strontium titanate(SrTiO_(3))is a thermoelectric material with large Seebeck coefficient that has potential applications in high-temperature power generators.To simultaneously achieve a low thermal conductivity and hi...Strontium titanate(SrTiO_(3))is a thermoelectric material with large Seebeck coefficient that has potential applications in high-temperature power generators.To simultaneously achieve a low thermal conductivity and high electrical conductivity,polycrystalline SrTiO_(3)with a multi-scale architecture was designed by the co-doping with lanthanum,cerium,and niobium.High-quality nano-powders were synthesized via a hydrothermal method.Nano-inclusions and a nano/micro-sized second phase precipitated during sintering to form mosaic crystal-like and epitaxial-like structures,which decreased the thermal conductivity.Substituting trivalent Ce and/or La with divalent Sr and substituting pentavalent Nb with tetravalent Ti enhanced the electrical conductivity without decreasing the Seebeck coefficient.By optimizing the dopant type and ratio,a low thermal conductivity of 2.77 W·m^(-1)·K^(-1)and high PF of 1.1 mW·m^(-1)·K^(-2)at 1000 K were obtained in the sample co-doped with 5-mol%La,5-mol%Ce,and 5-mol%Nb,which induced a large ZT of 0.38 at 1000 K.展开更多
据统计,全国范围内乙型肝炎病毒(hepatitis B virus,HBV)感染率仍高,发生慢加急性肝衰竭(acute-onchronic liver failure,ACLF)病死率高.近年,针对慢性乙型肝炎相关的慢加急性肝衰竭(hepatitis B virus related acute-on-chronic liver ...据统计,全国范围内乙型肝炎病毒(hepatitis B virus,HBV)感染率仍高,发生慢加急性肝衰竭(acute-onchronic liver failure,ACLF)病死率高.近年,针对慢性乙型肝炎相关的慢加急性肝衰竭(hepatitis B virus related acute-on-chronic liver failure,HBV-ACLF)粪便菌群的研究结果发现,肠道微生态影响着HBV-ACLF的发生、发展及转归.但粪便菌群不能完全替代整个肠道微生态,十二指肠黏膜微生态研究或许是一个新方向.本文将从机制、生理、解剖特点方面,对十二指肠黏膜菌群关于HBV-ACLF临床转归的影响作一综述.展开更多
In order to decrease the content of heavy metals in the crops soils, a novel method based on using an aqueous solution bearing cysteamine as the key ingredient was studied to extract the polluted heavy metals includin...In order to decrease the content of heavy metals in the crops soils, a novel method based on using an aqueous solution bearing cysteamine as the key ingredient was studied to extract the polluted heavy metals including Cd, Cu, Zn, Ni and Pb. By using the single-factor method, remediation-related technical index were screened and they are, respectively, applied to the solid material whereby the heavy metals are released and extracted from the solid material. The biomass solution residues remaining in the solid material after the heavy metal extraction procedure is rapidly biodegradable, so that no objectionable traces remain in the solid materials or soils.展开更多
Dear Editor: I am Dr Xiao-Mei Ma, from the Department of Pathology in Changzheng Hospital at the Second Military Medical University, Shanghai, China. We present here a case report of a seminal vesicle cyst (SVC) i...Dear Editor: I am Dr Xiao-Mei Ma, from the Department of Pathology in Changzheng Hospital at the Second Military Medical University, Shanghai, China. We present here a case report of a seminal vesicle cyst (SVC) in a young man with epididymal tissue in a dysgenetic kidney and ectopic ureteral insertion. SVCs are usually found in the second to fourth decades of life. SVCs can be congenital or acquired. Congenital SVCs seem to be invariably associated with renal dysplasia, hypoplasia, agenesis and duplication abnormalities in the same side, with the exception of two cases .展开更多
文摘Background:Cytomegalovirus(CMV)reactivation is linked to a high mortality rate,especially among the elderly.Prior research suggests that renin-angiotensin system(RAS)inhibitors may influence both the onset and prognosis of pneumonia.This study aims to examine the causal relationship between RAS inhibitor use and the risk of CMV pneumonia using Mendelian randomization(MR)analysis.Methods:We conducted an analysis using data from two genome-wide association studies(GWAS)involving individuals of European ancestry.This dataset included individuals treated with RAS inhibitors and those with CMV pneumonia.We assessed the relationship between RAS inhibitor use and CMV pneumonia risk using the inverse variance weighted(IVW)method.The results were further evaluated for pleiotropy,heterogeneity,and robustness.Results:The Mendelian randomization(MR)analysis revealed a causal relationship between RAS inhibitor use and an increased risk of CMV pneumonia(IVW:odds ratio[OR]=2.73;95%confidence interval[CI]=1.11-6.73;P=0.028).Conclusions:Our finding indicate a positive causal relationship between the use of RAS inhibitors and the onset of CMV pneumonia.
基金Supported by Natural Science Foundation of Shandong Province, No. 032050113
文摘AIM: To observe changes of mitochondria and investigate the effect of ethanol on mitochondrial perme- ability transition pore (PTP), mitochondrial membrane potential (MMP, ΔΨm) and intracellular calcium concentration in hepatocytes by establishing an animal model of alcoholic liver disease (ALD). METHODS: Fourty adult male Wistar rats were randomly divided into two groups, the model group (20) was administered alcohol intragastrically plus an Oliver oil diet to establish an ALD model, and the control group (20) was given an equal amount of normal saline. The ultramicrostructural changes of mitochondria were observed under electron microscopy. Mitochondria of liver was extracted, and patency of PTP, mitochondrial membrane potential (ΔΨm), mitochondrial mass and intracellular calcium concentration of isolated hepacytes were detected by flow cytometry using rhodamine123 (Rh123), Nonyl-Acridine Orange and calcium fluorescent probe Fluo-3/AM, respectively. RESULTS: Membrane and cristae were broken or disappeared in mitochondria in different shapes under electron microscopy. Some mitochondria showed U shape or megamitochondrion. In the model group, liver mitochondria PTP was broken, and mitochondria swelled, the absorbance at 450 nm, A540 decreased (0.0136 ± 0.0025 vs 0.0321 ± 0.0013, model vs control, P < 0.01); mitochondria transmembrane potential (239.4638 ± 12.7263 vs 377.5850 ± 16.8119, P < 0.01) was lowered; mitochondrial mass (17.4350 ± 1.9880 vs 31.6738 ± 3.4930, P < 0.01); and [Ca2+]i was increased in liver cells (7.0020 ± 0.5008 vs 10.2050 ± 0.4701, P < 0.01).CONCLUSION: Chronic alcohol intake might lead to broken mitochondria PTP, decreased mitochondria membrane potential and injury, and elevated intracellular Ca2+ production. Ethanol-induced chondriosome injury may be an important mechanism of alcoholic diseases.
文摘The core-shell 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane/2,4,6-Trinitrotoluene(CL-20/TNT)composite was prepared by spray-drying method in which sensitive high energy explosive(CL-20)was coated with insensitive explosive(TNT).The structure and properties of different formulations of CL-20/TNT composite and CL-20/TNT mixture were characterized by scanning electron microscopy(SEM),Transmission electron microscopy(TEM),Laser particle size analyzer,X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD),differential scanning calorimetry(DSC),impact sensitivity test and detonation performance.The results of SEM,TEM,XPS and XRD show that e-CL-20 particles are coated by TNT.When the ratio of CL-20/TNT is 75/25,core-shell structure is well formed,and thickness of the shell is about 20e30 nm.And the analysis of heat and impact show that with the increase of TNT content,the TNT coating on the core-shell composite material can not only catalyze the thermal decomposition of core material(CL-20),but also greatly reduce the impact sensitivity.Compared with the CL-20/TNT mixture(75/25)at the same ratio,the characteristic drop height of core-shell CL-20/TNT composite(75/25)increased by 47.6%and the TNT coating can accelerate the nuclear decomposition in the CL-20/TNT composites.Therefore,the preparation of the core-shell composites can be regarded as a unique means,by which the composites are characterized by controllable decomposition rate,high energy and excellent mechanical sensitivity and could be applied to propellants and other fields.
基金The project was supported by Equipment Pre-research Key Laboratory Fund(No.6142020305)The authors would like to thank Shiyanjia Lab(www.shiyanjia.com)for the support of XPS test.
文摘Hexagonal boron nitride nanosheets(HBNNSs)have huge potential in the field of coating materials owing to their remarkable chemical stability,mechanical strength and thermal conductivity.Thin-layer hBNNSs were obtained by a liquid-phase exfoliation of h-BN powders and incorporated into EVA coatings for improving the safety performance of 1,3,5,7-tetranitro-1,3,5,7-tetrazocane(HMX).HBNNSs and ethylene-vinyl acetate copolymer(EVA)were introduced to HMX by a solvent-slurry process.For comparison,the HMX/EVA and HMX/EVA/graphene(HMX/EVA/G)composites were also prepared by a similar process.The morphology,crystal form,surface element distribution,thermal decomposition property and impact sensitivity of HMX/EVA/hBNNSs composites were contrastively investigated.Results showed that as prepared HMX/EVA/hBNNSs composites were well coated with hBNNSs and EVA,and exhibited better thermal stability and lower impact sensitivity than that of HMX/EVA and HMX/EVA/G composites,suggesting superior performance of desensitization of hBNNSs in explosives.
基金Supported by Grants from National Natural Science Foundation of China,No.81273743,No.81473641and 215 Program,No.2013-2-11
文摘AIM: To establish a clinical scoring model to predict risk of acute-on-chronic liver failure(ACLF) in chronic hepatitis B(CHB) patients.METHODS: This was a retrospective study of 1457 patients hospitalized for CHB between October 2008 and October 2013 at the Beijing Ditan Hospital, Capital Medical University, China. The patients were divided into two groups: severe acute exacerbation(SAE) group(n = 382) and non-SAE group(n = 1075). The SAE group was classified as the high-risk group based on the higher incidence of ACLF in this group than in the non-SAE group(13.6% vs 0.4%). Two-thirds of SAE patients were randomly assigned to risk-model derivation and the other one-third to model validation. Univariate risk factors associated with the outcome were entered into a multivariate logistic regression model for screening independent risk factors. Each variable was assigned an integer value based on the regression coefficients, and the final score was the sum of these values in the derivation set. Model discrimination and calibration were assessed using area under the receiver operating characteristic curve and the Hosmer-Lemeshow test. RESULTS: The risk prediction scoring model includedthe following four factors: age ≥ 40 years, total bilirubin ≥ 171 μmol/L, prothrombin activity 40%-60%, and hepatitis B virus DNA > 107 copies/m L. The sum risk score ranged from 0 to 7; 0-3 identified patients with lower risk of ACLF, whereas 4-7 identified patients with higher risk. The Kaplan-Meier analysis showed the cumulative risk for ACLF and ACLF-related death in the two risk groups(0-3 and 4-7 scores) of the primary cohort over 56 d, and log-rank test revealed a significant difference(2.0% vs 33.8% and 0.8% vs 9.4%, respectively; both P < 0.0001). In the derivation and validation data sets, the model had good discrimination(C index = 0.857, 95% confidence interval: 0.800-0.913 and C index = 0.889, 95% confidence interval: 0.820-0.957, respectively) and calibration demonstrated by the Hosmer-Lemeshow test(χ2 = 4.516, P = 0.808 and χ2 = 1.959, P = 0.923, respectively).CONCLUSION: Using the scoring model, clinicians can easily identify patients(total score ≥ 4) at high risk of ACLF and ACLF-related death early during SAE.
基金Supported by a grant from Shandong Natural Sciences Foundation(Y2005C96).
文摘Objective To examine whether ischemic preconditioning (IPC) can protect neuron against delayed death in CA1 subfield of hippocampus following reperfusion of a lethal ischemia in rats, and explore the role of p53 and bax in this process. Methods We examined the effect of IPC on delayed neuron death, neuron apoptosis, expressions of p53 and bax gene in the CA1 area of hippocampus in the rats using HE staining, flow cytometry, RT-PCR, and immunohistochemistry technique. Results IPC enhanced the quantity of survival cells in the CA1 region of hippocampus (216±9 cells/0.72 mm2 vs. 30±5 cells/0.72 mm2, P<0.01), decreased the percentages of apoptotic neurons of hippocampus caused by ischemia/reperfusion (2.06%±0.21% vs. 4.27%±0.08%, P<0.01), and weakened the expressions of p53 and bax gene of hippocampus compared with ischemia/reperfusion without IPC. Conclusion IPC can protect the neurons in the CA1 region of hippocampus against apoptosis caused by ische- mia/reperfusion, and this process may be related to the reduced expressions of p53 and bax.
文摘AIM: To investigate the regulatory effect of Vδ1 T cells and the antitumor activity of Vδ2 T cells in rectal cancer.METHODS: Peripheral blood, tumor tissues and para-carcinoma tissues from 20 rectal cancer patients were collected. Naïve CD4 T cells from the peripheral blood of rectal cancer patients were purified by negative selection using a Naive CD4<sup>+</sup> T Cell Isolation Kit II (Miltenyi Biotec). Tumor tissues and para-carcinoma tissues were minced into small pieces and digested in a triple enzyme mixture containing collagenase type IV, hyaluronidase, and deoxyribonuclease for 2 h at room temperature. After digestion, the cells were washed twice in RPMI1640 and cultured in RPMI1640 containing 10% human serum supplemented with L-glutamine and 2-mercaptoethanol and 1000 U/mL of IL-2 for the generation of T cells. Vδ1 T cells and Vδ2 T cells from tumor tissues and para-carcinoma tissues were expanded by anti-TCR γδ antibodies. The inhibitory effects of Vδ1 T cells on naïve CD4 T cells were analyzed using the CFSE method. The cytotoxicity of Vδ2 T cells on rectal cancer lines was determined by the LDH method.RESULTS: The percentage of Vδ1 T cells in rectal tumor tissues from rectal cancer patients was significantly increased, and positively correlated with the T stage. The percentage of Vδ2 T cells in rectal tumor tissues from rectal cancer patients was significantly decreased, and negatively correlated with the T stage. After culture for 14 d with 1 μg/mL anti-TCR γδ antibodies, the percentage of Vδ1 T cells from para-carcinoma tissues was 21.45% ± 4.64%, and the percentage of Vδ2 T cells was 38.64% ± 8.05%. After culture for 14 d, the percentage of Vδ1 T cells from rectal cancer tissues was 67.45% ± 11.75% and the percentage of Vδ2 T cells was 8.94% ± 2.85%. Tumor-infiltrating Vδ1 T cells had strong inhibitory effects, and tumor-infiltrating Vδ2 T cells showed strong cytolytic activity. The inhibitory effects of Vδ1 T cells from para-carcinoma tissues and from rectal cancer tissue were not significantly different. In addition, the cytolytic activities of Vδ2 T cells from para-carcinoma tissues and from rectal cancer tissues were not significantly different.CONCLUSION: A percentage imbalance in Vδ1 and Vδ2 T cells in rectal cancer patients may contribute to the development of rectal cancer.
基金financially supported by the National Natural Science Foundation of China(Grant No.52004317,42090024)the Natural Science Foundation of Shandong Province of China(No.ZR2020ME091)+1 种基金the Fundamental Research Funds for the Central Universities(20CX06016A)the National Science and Technology Major Project(2017ZX05049-004)
文摘Shale oil formations contain both inorganic and organic media.The organic matter holds both free oil in the pores and dissolved oil within the kerogen molecules.The free oil flow in organic pores and the dissolved oil diffusion in kerogen molecules are coupled together.The molecular flow of free n-alkanes is an important process of shale oil accumulation and production.To study the dynamics of imbibition process of n-alkane molecules into kerogen slits,molecular dynamics(MD)simulations are conducted.Effects of slit width,temperature,and n-alkane types on the penetration speed,dynamic contact angle,and molecular conformations were analyzed.Results showed that molecular transportation of n-alkanes is dominated by molecular structure and molecular motion at this scale.The space-confinement conformational changes of molecules slow down the filling speeds in the narrow slits.The n-alkane molecules with long carbon chains require more time to undergo conformational changes.The high content of short-chain alkanes and high temperature facilitate the flow of alkane mixtures in kerogen slits.Results obtained from this study are useful for understanding the underlying nanoscale flow mechanism in shale formations.
基金the National Natural Science Foundation of China (21473111)the Fundamental Research Funds for the Central Universities (GK201701007)
文摘The research on electrocatalysts with relatively lower price than Pt and excellent electrocatalytic performance for the cathode oxygen reduction reaction(ORR) and anode methanol oxidation reaction(MOR) is vital for the development of direct methanol fuel cells(DMFCs). In this work, we develop a cyanogel-reduction method to synthesize reduced graphene oxide(rGO) supported highly dispersed PdNi alloy nanocrystals(PdNi/rGO) with high alloying degree and tunable Pd/Ni ratio. The large specific surface area and the d-band center downshift of Pd result in excellent activity of Pd4 Ni1/rGO nanohybrids for the ORR. The modification of Pd electronic structure can facilitate the adsorption of CH3 OH on Pd surface and the highly oxophilic property of Ni can eliminate/mitigate the COadsintermediates poisoning, which make PdNi/r GO nanohybrids possess superior MOR activity. In addition, rGO improve the stability of PdNi alloy nanocrystals for the ORR and MOR. Due to high activity and stability for the ORR and MOR, PdNi/rGO nanohybrids are promising to be an available bifunctional electrocatalyst in DMFCs.
基金Supported by the Clinical Innovation Project from the Southwest Hospital,No.SWH2016ZDCX1007
文摘BACKGROUND Porphyria is a rare disease with complex classification. Erythropoietic protoporphyria(EPP) is an autosomal recessively inherited disease, and most are caused by mutations in the FECH gene. EPP combined with liver injury is even rarer.CASE SUMMARY This paper reports a case of EPP which was admitted to the hospital with abnormal liver function and diagnosed by repeated questioning of medical history, screening of common causes of severe liver injury, and second generation sequencing of the whole exon genome. We also summarize the clinical characteristics of EPP with liver injury, and put forward some suggestions on EPP to provide a reference for the diagnosis of such rare disease.CONCLUSION A new mutation locus(c.32_35 dupCCCT) which may be related to the disease was found by detecting the FECH gene in the pedigree of this case.
基金financially supported by the National Natural Science Foundation of China(Grant No.41972138)the Technology Major Project of China(Grant No.ZD2019-183007,2016ZX05002-002)。
文摘Microscopic seepage characteristics are critical for the evaluation of tight sandstone reservoirs.In this study,a digital core approach integrating microscopic seepage simulation and CT scanning was developed to characterize microscopic seepage and fracture effectiveness(the ratio of micro-fractures that contributes to fluid flow)of tight sandstones.Numerical simulations were carried out for characterizations of tight sandstones.The results show that the axial permeability of the investigated cylindrical tight sandstone from Junggar Basin in China is 0.460μm~2,while the radial permeability is 0.3723μm~2,and the axial and radial effective fracture ratios are 0.4387 and 0.4806,respectively,indicating that cracks are not fully developed and the connectivity between micro-cracks is poor.Directional permeability that is difficult to measure by laboratory experiments can be obtained readily using the proposed method in this paper.The results provide important information for improving the exploration and development of tight sandstone reservoirs.
基金International Science and Technology Cooperation Project of Jilin Province Science and Technology Department,China,No.20200801077GHScience and Technology Project of Jilin Provincial Department of Finance,China,No.JCSZ2019378-8Jilin Provincial Development and Reform Commission Project,China,No.2019C051-5.
文摘BACKGROUND Mammary analogue secretory carcinoma(MASC)is a rare low-grade malignant salivary gland tumor.The morphological and immunohistochemical features of MASC closely resemble those of breast secretory carcinoma.The key characteristics of the lesion are a lack of pain and slow growth.There is no obvious specificity in the clinical manifestations and imaging features.The diagnosis of the disease mainly depends on the detection of the MASC-specific ETV6-NTRK3 fusion gene.CASE SUMMARY This report describes a rare case of a 32-year-old male patient who presented with a gradually growing lesion that was initially diagnosed as breast-like secretory carcinoma of the right parotid gland.Imaging and histological investigations were used to overcome the diagnostic difficulties.The lesion was managed with right parotidectomy,facial nerve preservation,biological patch implantation to restore the resulting defect,and postoperative radiotherapy.On postoperative follow-up,the patient reported a mild facial deformity with no complications,signs of facial paralysis,or Frey’s syndrome.CONCLUSION The imaging and histological diagnostic challenges for MASC are discussed.
基金This work received financial support from the National Natural Science Foundation of China(21902116)Scientific Research Foundation of Technology Department of Liaoning province of China(2022-MS-379)Liaoning Revitalization Talents Program(XLYC1902070).
文摘Oxidative dehydrogenation of propane is an attractive route for the synthesis of propylene due to its favorable thermodynamic and kinetic characteristics, however, it is challenging to realize high selectivity towards propylene. Recently, it has been discovered that boron nitride (BN) is a promising catalyst that affords superior selectivity towards propylene in oxidative dehydrogenation of propane. Summarizing the progress and unravelling the reaction mechanism of BN in oxidative dehydrogenation of propane are of great significance for the rational design of efficient catalysts in the future. Herein, in this review, the underlying reaction mechanisms of oxidative dehydrogenation of propane over BN are extracted;the developed BN catalysts are classified into pristine BN, functionalized BN, supported BN and others, and the applications of each category of BN catalysts in oxidative dehydrogenation of propane are summarized;the challenges and opportunities on oxidative dehydrogenation of propane over BN are pointed out, aiming to inspire more studies and advance this research field.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51702168 and 51532006).
文摘Strontium titanate(SrTiO_(3))is a thermoelectric material with large Seebeck coefficient that has potential applications in high-temperature power generators.To simultaneously achieve a low thermal conductivity and high electrical conductivity,polycrystalline SrTiO_(3)with a multi-scale architecture was designed by the co-doping with lanthanum,cerium,and niobium.High-quality nano-powders were synthesized via a hydrothermal method.Nano-inclusions and a nano/micro-sized second phase precipitated during sintering to form mosaic crystal-like and epitaxial-like structures,which decreased the thermal conductivity.Substituting trivalent Ce and/or La with divalent Sr and substituting pentavalent Nb with tetravalent Ti enhanced the electrical conductivity without decreasing the Seebeck coefficient.By optimizing the dopant type and ratio,a low thermal conductivity of 2.77 W·m^(-1)·K^(-1)and high PF of 1.1 mW·m^(-1)·K^(-2)at 1000 K were obtained in the sample co-doped with 5-mol%La,5-mol%Ce,and 5-mol%Nb,which induced a large ZT of 0.38 at 1000 K.
文摘据统计,全国范围内乙型肝炎病毒(hepatitis B virus,HBV)感染率仍高,发生慢加急性肝衰竭(acute-onchronic liver failure,ACLF)病死率高.近年,针对慢性乙型肝炎相关的慢加急性肝衰竭(hepatitis B virus related acute-on-chronic liver failure,HBV-ACLF)粪便菌群的研究结果发现,肠道微生态影响着HBV-ACLF的发生、发展及转归.但粪便菌群不能完全替代整个肠道微生态,十二指肠黏膜微生态研究或许是一个新方向.本文将从机制、生理、解剖特点方面,对十二指肠黏膜菌群关于HBV-ACLF临床转归的影响作一综述.
文摘In order to decrease the content of heavy metals in the crops soils, a novel method based on using an aqueous solution bearing cysteamine as the key ingredient was studied to extract the polluted heavy metals including Cd, Cu, Zn, Ni and Pb. By using the single-factor method, remediation-related technical index were screened and they are, respectively, applied to the solid material whereby the heavy metals are released and extracted from the solid material. The biomass solution residues remaining in the solid material after the heavy metal extraction procedure is rapidly biodegradable, so that no objectionable traces remain in the solid materials or soils.
文摘Dear Editor: I am Dr Xiao-Mei Ma, from the Department of Pathology in Changzheng Hospital at the Second Military Medical University, Shanghai, China. We present here a case report of a seminal vesicle cyst (SVC) in a young man with epididymal tissue in a dysgenetic kidney and ectopic ureteral insertion. SVCs are usually found in the second to fourth decades of life. SVCs can be congenital or acquired. Congenital SVCs seem to be invariably associated with renal dysplasia, hypoplasia, agenesis and duplication abnormalities in the same side, with the exception of two cases .