Clinicopathological analysis of small intestinal metastasis from extra-abdominal/extra-pelvic malignancy

BACKGROUND The metastatic tumors in the small intestine secondary to extra-abdominal/extrapelvic malignancy are extremely rare.However,the small intestine metastases are extremely prone to misdiagnosis and missed diagnosis due to the lack of specific clinical manifestations and examination methods,thus delaying its treatment.Therefore,in order to improve clinical diagnosis and treatment capabilities,it is necessary to summarize its clinical pathological characteristics and prognosis.AIM To summarize the clinicopathological characteristics of patients with small intestinal metastases from extra-abdominal/extra-pelvic malignancy,and to improve the clinical capability of diagnosis and treatment for rare metastatic tumors in the small intestine.METHODS The clinical data of patients with small intestinal metastases from extra-abdominal/extra-pelvic malignancy were retrieved and summarized,who admitted to and treated in the Air Force Medical Center,Chinese People’s Liberation Army.Then descriptive statistics were performed on the general conditions,primary tumors,secondary tumors in the small intestine,diagnosis and treatment processes,and prognosis.RESULTS Totally 11 patients(9 males and 2 females)were enrolled in this study,including 8 cases(72.3%)of primary lung cancer,1 case(9.1%)of malignant lymphoma of the thyroid,1 case(9.1%)of cutaneous malignant melanoma,and 1 case(9.1%)of testicular cancer.The median age at the diagnosis of primary tumors was 57.9 years old,the median age at the diagnosis of metastatic tumors in the small intestine was 58.81 years old,and the average duration from initial diagnosis of primary tumors to definite diagnosis of small intestinal metastases was 9 months(0-36 months).Moreover,small intestinal metastases was identified at the diagnosis of primary tumors in 4 cases.The small intestinal metastases were distributed in the jejunum and ileum,with such clinical manifestations as hematochezia(5,45.4%)and abdominal pain,vomiting and other obstruction(4,36.4%).In addition,2 patients had no obvious symptoms at the diagnosis of small intestinal metastases,and 5 patients underwent radical resection of small intestinal malignancies and recovered well after surgery.A total of 3 patients did not receive subsequent treatment due to advanced conditions.CONCLUSION Small intestinal metastases of extra-abdominal/extra-pelvic malignancy is rare with high malignancy and great difficulty in diagnosis and treatment.Clinically,patients with extra-abdominal/extra-pelvic malignancy should be alert to the occurrence of this disease,and their prognosis may be improved through active surgery combined with standard targeted therapy.

Clinical features,diagnosis,and treatment of Peutz-Jeghers syndrome:Experience with 566 Chinese cases

BACKGROUND Peutz-Jeghers syndrome(PJS)is a clinically rare disease with pigmented spots on the lips and mucous membranes and extremities,scattered gastrointestinal polyps,and susceptibility to tumors as clinical manifestations.Effective preventive and curative methods are still lacking.Here we summarize our experience with 566 Chinese patients with PJS from a Chinese medical center with regard to the clinical features,diagnosis,and treatment.AIM To explore the clinical features,diagnosis,and treatment of PJS in a Chinese medical center.METHODS The diagnosis and treatment information of 566 cases of PJS admitted to the Air Force Medical Center from January 1994 to October 2022 was summarized.A clinical database was established covering age,gender,ethnicity,family history,age at first treatment,time and sequence of appearance of mucocutaneous pigmentation,polyp distribution,quantity,and diameter,frequency of hospitalization,fre-quency of surgical operations,etc.The clinical data was retrospectively analyzed using SPSS 26.0 software,with P<0.05 considered statistically significant.RESULTS Of all the patients included,55.3%were male and 44.7%were female.Median time to the appearance of mucocutaneous pigmentation was 2 years,and median time from the appearance of mucocutaneous pigmentation to the occurrence of abdominal symptoms was 10 years.The vast majority(92.2%)of patients underwent small bowel endoscopy and treatment,with 2.3%having serious complications.There was a statistically significant difference in the number of enteroscopies between patients with and without canceration(P=0.004,Z=-2.882);71.2%of patients underwent surgical operation,75.6%of patients underwent surgical operation before the age of 35 years,and there was a statistically significant difference in the frequency of surgical operations between patients with and without cancer(P=0.000,Z=-5.127).At 40 years of age,the cumulative risk of intussusception in PJS was approximately 72.0%,and at 50 years,the cumulative risk of intussusception in PJS was approximately 89.6%.At 50 years of age,the cumulative risk of cancer in PJS was approximately 49.3%,and at 60 years of age,the cumulative risk of cancer in PJS was approximately 71.7%.CONCLUSION The risk of intussusception and cancer of PJS polyps increases with age.PJS patients≥10 years old should undergo annual enteroscopy.Endoscopic treatment has a good safety profile and can reduce the occurrence of polyps intussusception and cancer.Surgery should be conducted to protect the gastrointestinal system by removing polyps.

Potential seismic landslide hazard and engineering effect in the Ya’an-Linzhi section of the Sichuan-Tibet transportation corridor, China

The Sichuan-Tibet transportation corridor is located at the eastern margin of the Qinghai-Tibet Plateau,where the complex topography and geological conditions,developed geo-hazards have severely restricted the planning and construction of major projects.For the long-term prevention and early control of regional seismic landslides,based on analyzing seismic landslide characteristics,the Newmark model was used to carry out the potential seismic landslide hazard assessment with a 50-year beyond probability 10%.The results show that the high seismic landslide hazard is mainly distributed along large active tectonic belts and deep-cut river canyons,and are significantly affected by the active tectonics.The low seismic landslide hazard is mainly distributed in the flat terrain such as the Quaternary basins,broad river valleys,and plateau planation planes.The major east-west linear projects mainly pass through five areas with high seismic landslide hazard:Luding-Kangding section,Yajiang-Xinlong(Yalong river)section,Batang-Baiyu(Jinsha river)section,Basu(Nujiang river)section,and Bomi-Linzhi(eastern Himalaya syntaxis)section.The seismic action of the Bomi-Linzhi section can also induce high-risk geo-hazard chains such as the high-level glacial lake breaks and glacial debris flows.The early prevention of seismic landslides should be strengthened in the areas with high seismic landslide hazard.

Peutz-Jeghers syndrome without STK11 mutation may correlate with less severe clinical manifestations in Chinese patients

BACKGROUND Peutz-Jeghers syndrome(PJS) is an autosomal dominant genetic disease with skin mucosal pigment spots and gastrointestinal(GI) multiple hamartoma polyps as clinical characteristics. At present, it is considered that the germline mutation of STK11 gene is the genetic cause of PJS. However, not all PJS patients can be detected STK11 germline mutations. The specific clinical characteristics of these PJS patients without STK11 mutation is an interesting clinical question. Or, like wild type GI stromal tumor, whether these PJS without STK11 mutation are also called PJS is worth discussing. Therefore, we designed the study to understand the clinical characteristics of these PJS patients without STK11 mutation.AIM To investigates whether PJS patients with known STK11 mutations have a more severe spectrum of clinical phenotypes compared to those without.METHODS A total of 92 patients with PJS admitted to the Air Force Medical Center from 2010 to 2022 were randomly selected for study. Genomic DNA samples were extracted from peripheral blood samples, and pathogenic germline mutations of STK11 were detected by high-throughput next-generation gene sequencing. Clinicalpathologic manifestations of patients with and without STK11/LKB1 mutations were compared.RESULTS STK11 germline mutations were observed in 73 patients with PJS. Among 19 patients with no detectable STK11 mutations, six had no pathogenic germline mutations of other genes, while 13 had other genetic mutations. Compared with PJS patients with STK11 mutations, those without tended to be older at the age of initial treatment, age of first intussusception and age of initial surgery. They also had a lower number of total hospitalizations relating to intussusception or intestinal obstruction, and a lower load of small intestine polyps.CONCLUSION PJS patients without STK11 mutations might have less severe clinical-pathologic manifestations than those with.

Analysis of clinicopathological features and prognostic factors of breast cancer brain metastasis

BACKGROUND Breast cancer(BC)has become the most common malignancy in women.The incidence and detection rates of BC brain metastasis(BCBM)have increased with the progress of imaging,multidisciplinary treatment techniques and the extension of survival time of BC patients.BM seriously affects the quality of life and survival prognosis of BC patients.Therefore,clinical research on the clinicopathological features and prognostic factors of BCBM is valuable.By analyzing the clinicopathological parameters of BCBM patients,and assessing the risk factors and prognostic indicators,we can perform hierarchical diagnosis and treatment on the high-risk population of BCBM,and achieve clinical benefits of early diagnosis and treatment.AIM To explore the clinicopathological features and prognostic factors of BCBM,and provide references for diagnosis,treatment and management of BCBM.METHODS The clinicopathological data of 68 BCBM patients admitted to the Air Force Medical Center,Chinese People’s Liberation Army(formerly Air Force General Hospital)from 2000 to 2022 were collected.Another 136 BC patients without BM were matched at a ratio of 1:2 based on the age and site of onset for retrospective analysis.Categorical data were subjected to χ^(2) test or Fisher’s exact probability test,and the variables with P<0.05 in the univariate Cox proportional hazards model were incorporated into the multivariate model to identify high-risk factors and independent prognostic factors of BCBM,with a hazard ratio(HR)>1 suggesting poor prognostic factors.The survival time of patients was estimated by the Kaplan-Meier method,and overall survival was compared between groups by log-rank test.RESULTS Multivariate Cox regression analysis showed that patients with stage Ⅲ/Ⅳ tumor at initial diagnosis[HR:5.58,95% confidence interval(CI):1.99–15.68],lung metastasis(HR:24.18,95%CI:6.40-91.43),human epidermal growth factor receptor 2(HER2)-overexpressing BC and triple-negative BC were more prone to BM.As can be seen from the prognostic data,52 of the 68 BCBM patients had died by the end of follow-up,and the median time from diagnosis of BC to the occurrence of BM and from the occurrence of BM to death or last follow-up was 33.5 and 14 mo,respectively.It was confirmed by multivariate Cox regression analysis that patients with neurological symptoms(HR:1.923,95%CI:1.005-3.680),with bone metastasis(HR:2.011,95%CI:1.056-3.831),and BM of HER2-overexpressing and triple-negative BC had shorter survival time.CONCLUSION HER2-overexpressing,triple-negative BC,late tumor stage and lung metastasis are risk factors of BM.The presence of neurological symptoms,bone metastasis,and molecular type are influencing prognosis factors of BCBM.

Effect of existence state of asphaltenes on the asphaltenes-wax interaction in wax deposition

Asphaltenes are the most elusive substances in waxy crude oil,especially the complex structures,which leads to significant precipitation and aggregation characteristics of asphaltenes,and affects the asphaltenes-wax interaction.In this study,the concept of the existence state of asphaltenes was introduced to semi-quantitatively investigate the precipitation and aggregation characteristics of asphaltenes.On this basis,the influence of the existence state of asphaltenes on wax deposition was studied by coldfinger device and high-temperature gas chromatography,and the composition and properties of the deposits were analyzed.Four main findings were made:(1)As the asphaltene concentration increases,the existence state of asphaltenes gradually transitions from dispersed state to aggregated state,and the asphaltene concentration of 0.30 wt%in this study is the starting point of the transition.(2)The existence state of asphaltenes in crude oil does affect the process of wax deposition,as shown in the fact that the dispersed asphaltenes promote the occurrence of wax deposition,while the aggregated asphaltenes can inhibit wax deposition.(3)In the presence of the aggregated asphaltenes,that is,when the asphaltene concentration is higher than 0.30 wt%,the shedding phenomenon of deposit layer was observed,and with the increase of aggregated asphaltenes,the deposit layer fell off earlier.(4)With the increase of the dispersed asphaltenes,the wax appearance temperature(WAT)and wax content of the deposits all showed an increasing trend,while with the appearance of the aggregated asphaltenes,the above situation was reversed.The findings of this study can help for better understanding of the interaction between the asphaltenes and wax in wax deposition.

Idiopathic abdominal cocoon syndrome with unilateral abdominal cryptorchidism and greater omentum hypoplasia in a young case of small bowel obstruction

Abdominal cocoon syndrome(ACS) is a rare cause of intestinal obstruction due to total or partial encapsulation of the small intestine by a fibrocollagenous membrane. Idiopathic ACS with abdominal cryptorchidism and greater omentum hypoplasia is even rarer clinically. We successfully treated a 26-year-old male case of small bowel obstruction with acute peritonitis. He was finally diagnosed with idiopathic ACS with unilateral abdominal cryptorchidism and greater omentum hypoplasia during exploratory laparotomy. He then underwent enterolysis, cryptorchidectomy, and appendectomy. He recovered gradually from the operations and early postoperative inflammatory ileus. There has been no recurrence of intestinal obstruction since the operation, and he is still in follow-up. We analyzed his clinical data and retrospectively reviewed the literature, and our findings may be helpful for the clinical diagnosis and treatment on ACS.

Preparation of high-strength Al-Mg-Si-Cu-Fe alloy via heat treatment and rolling

An Al-Mg-Si-Cu-Fe alloy was solid-solution treated at 560℃ for 3 h and then cooled by water quenching or furnace cooling. The alloy samples which underwent cooling by these two methods were rolled at different temperatures. The microstructure and mechanical properties of the rolled alloys were investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis, and tensile testing. For the water-quenched alloys, the peak tensile strength and elongation occurred at a rolling temperature of 180℃. For the furnace-cooled alloys, the tensile strength decreased initially, until the rolling temperature of 420℃, and then increased;the elongation increased consistently with increasing rolling temperature. The effects of grain boundary hardening and dislocation hardening on the mechanical properties of these rolled alloys decreased with increases in rolling temperature. The mechanical properties of the 180℃ rolling water-quenched alloy were also improved by the presence ofβ″phase. Above 420℃, the effect of solid-solution hardening on the mechanical properties of the rolled alloys increased with increases in rolling temperature.

Numerical simulation and experimental verification of large-sized Zr-based bulk metallic glass ring-shaped parts in casting process

An outer ring of 29320 self-aliging roller bearing was used in an experimental study on the casting of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(22.5) amorphous alloy.Numerical simulations of mold filling and solidification processes were carried out to determine the velocity fields and temperature fields of the alloy melt during mold filling process as well as the temperature fields and temperature gradient fields in the course of the solidification.According to the results,a cast with a complete shape can be obtained at 1200℃under the condition that the cooling rate is greater than the critical cooling rate.The ring-shaped part with a thickness of 25 mm,an equivalent diameter of 22 mm,and a mass of 1.32 kg was prepared by gravity casting in a copper mold.X-ray diffraction and differential scanning calorimetry data revealed that the produced cast had the amorphous structure.

Study on the thixotropy and structural recovery characteristics of waxy crude oil emulsion

Waxy crude oil emulsion has thixotropic properties at the temperature near gel point,which is a macromechanical characterization of the structure failure and recovery of waxy crude oil emulsion.In this paper,the thixotropic behaviors of waxy crude oil emulsion near gel point were studied using hysteresis loop formed by stress linear increase and decrease,as well as the structural recovery characteristics.The influence of the loading conditions and water content on the thixotropy of waxy crude oil emulsion were analyzed with hysteresis loop area.The concept of"structural recovery"was introduced to study the degree of structural recovery after different stewing,and influencing factors were taken into account.Results have shown that for waxy crude oil emulsion,the failure to fully restore of the structure after lysis is the cause of the formation of hysteresis loop,and the loading conditions will not affect the strength of thixotropy and the degree of structural recovery.Additionally,the dispersed phase droplets weaken the thixotropy and structure recovery characteristics of waxy crude oil emulsion,and the greater the water content,the weaker the thixotropy.The findings can help to better understand the safe and economic operation of waxy crude oil-water pipeline transportation.

Must Peutz-Jeghers syndrome patients have the LKB1/STK11 gene mutation?A case report and review of the literature

Peutz-Jeghers syndrome(PJS) is an autosomal dominant inherited disease, which is characterized by mucocutaneous pigmentation and multiple gastrointestinal hamartoma polyps. The germline mutation of LKB1/STK11 gene on chromosome 19 p13.3 is considered to be the hereditary cause of PJS. However, must a patient with PJS have the LKB1/STK11 gene mutation? We here report a case of a male patient who had typical manifestations of PJS and a definite family history, but did not have LKB1/STK11 gene mutation. By means of high-throughput sequencing technology, only mutations in APC gene(c.6662 T > C: p.Met2221 Thr) and MSH6 gene(c.3488 A > T: p.Glu1163 Val) were detected. The missense mutations in APC and MSH6 gene may lead to abnormalities in structure and function of their expression products, and may result in the occurrence of PJS. This study suggests that some other genetic disorders may cause PJS besides LKB1/STK11 gene mutation.

Detection and analysis of common pathogenic germline mutations in Peutz-Jeghers syndrome

Different types of pathogenic mutations may produce different clinical phenotypes,but a correlation between Peutz-Jeghers syndrome(PJS)genotype and clinical phenotype has not been found.Not all patients with PJS have detectable mutations of the STK11/LKB1 gene,what is the genetic basis of clinical phenotypic heterogeneity of PJS?Do PJS cases without STK11/LKB1 mutations have other pathogenic genes?Those are clinical problems that perplex doctors.AIM The aim was to investigate the specific gene mutation of PJS,and the correlation between the genotype and clinical phenotype of PJS.METHODS A total of 24 patients with PJS admitted to the Air Force Medical Center,PLA(formerly the Air Force General Hospital,PLA)from November 1994 to January 2020 were randomly selected for inclusion in the study.One hundred thirty-nine common hereditary tumor-related genes including STK11/LKB1 were screened and analyzed for pathogenic germline mutations by high-throughput nextgeneration sequencing(NGS).The mutation status of the genes and their relationship with clinical phenotypes of PJS were explored.RESULTS Twenty of the 24 PJS patients in this group(83.3%)had STK11/LKB1 gene mutations,90%of which were pathogenic mutations,and ten had new mutation sites.Pathogenic mutations in exon 7 of STK11/LKB1 gene were significantly lower than in other exons.Truncation mutations are more common in exons 1 and 4 of STK11/LKB1,and their pathogenicity was significantly higher than that of missense mutations.We also found SLX4 gene mutations in PJS patients.CONCLUSION PJS has a relatively complicated genetic background.Changes in the sites responsible for coding functional proteins in exon 1 and exon 4 of STK11/LKB1 may be one of the main causes of PJS.Mutation of the SLX4 gene may be a cause of genetic heterogeneity in PJS.

Protective effect of mesenchymal stem cell-derived exosomal treatment of hippocampal neurons against oxygen-glucose deprivation/reperfusion-induced injury

BACKGROUND:Individuals who survive a cardiac arrest often sustain cognitive impairments due to ischemia-reperfusion injury.Mesenchymal stem cell(MSC)transplantation is used to reduce tissue damage,but exosomes are more stable and highly conserved than MSCs.This study was conducted to investigate the therapeutic effects of MSC-derived exosomes(MSC-Exo)on cerebral ischemia-reperfusion injury in an in vitro model of oxygen-glucose deprivation/reperfusion(OGD/R),and to explore the underlying mechanisms.METHODS:Primary hippocampal neurons obtained from 18-day Sprague-Dawley rat embryos were subjected to OGD/R treatment,with or without MSC-Exo treatment.Exosomal integration,cell viability,mitochondrial membrane potential,and generation of reactive oxygen species(ROS)were examined.Terminal deoxynucleotidyl transferase-mediated 2’-deoxyuridine 5’-triphosphate nickend labeling(TUNEL)staining was performed to detect neuronal apoptosis.Moreover,mitochondrial function-associated gene expression,Nrf2 translocation,and expression of downstream antioxidant proteins were determined.RESULTS:MSC-Exo attenuated OGD/R-induced neuronal apoptosis and decreased ROS generation(P<0.05).The exosomes reduced OGD/R-induced Nrf2 translocation into the nucleus(2.14±0.65 vs.5.48±1.09,P<0.01)and increased the intracellular expression of antioxidative proteins,including superoxide dismutase and glutathione peroxidase(17.18±0.97 vs.14.40±0.62,and 20.65±2.23 vs.16.44±2.05,respectively;P<0.05 for both).OGD/R significantly impaired the mitochondrial membrane potential and modulated the expression of mitochondrial functionassociated genes,such as PINK,DJ1,LRRK2,Mfn-1,Mfn-2,and OPA1.The abovementioned changes were partially reversed by exosomal treatment of the hippocampal neurons.CONCLUSIONS:MSC-Exo treatment can alleviate OGD/R-induced oxidative stress and dysregulation of mitochondrial function-associated genes in hippocampal neurons.Therefore,MSCExo might be a potential therapeutic strategy to prevent OGD/R-induced neuronal injury.

Mutation analysis of related genes in hamartoma polyp tissue of Peutz-Jeghers syndrome

BACKGROUND Peutz-Jeghers syndrome(PJS)is a rare disease with clinical manifestations of pigmented spots on the lips,mucous membranes and extremities,scattered gastrointestinal polyps,and susceptibility to tumors.The clinical heterogeneity of PJS is obvious,and the relationship between clinical phenotype and genotype is still unclear.AIM To investigate the mutation status of hereditary colorectal tumor-associated genes in hamartoma polyp tissue of PJS patients and discuss its relationship with the clinicopathological data of PJS.METHODS Twenty patients with PJS were randomly selected for this study and were treated in the Air Force Medical Center(former Air Force General Hospital)PLA between 2008 and 2017.Their hamartoma polyp tissues were used for APC,AXIN2,BMPR1A,EPCAM,MLH1,MLH3,MSH2,MSH6,MUTYH,PMS1,PMS2,PTEN,SMAD4,and LKB1/STK11 gene sequencing using next-generation sequencing technology.The correlations between the sequencing results and clinical pathological data of PJS were analyzed.RESULTS Fourteen types of LKB1/STK11 mutations were detected in 16 cases(80.0%),of which 8 new mutations were found(3 types of frameshift deletion mutations:c.243delG,c.363_364delGA,and c.722delC;2 types of frameshift insertions:c.144_145insGCAAG,and c.454_455insC;3 types of splice site mutations:c.464+1G>T,c.464+1G>A,and c.598-1G>A);9 cases(45.0%)were found to have 18 types of heterozygous mutations in the remaining 13 genes except LKB1/STK11.Of these,MSH2:c.792+1G>A,MSH6:c.3689C>G,c.4001+13C>CTTAC,PMS1:c.46C>t,and c.922G>A were new mutations.CONCLUSION The genetic mutations in hamartoma polyp tissue of PJS are complex and diverse.Moreover,other gene mutations in PJS hamartoma polyp tissue were observed,with the exception of LKB1/STK11 gene,especially the DNA mismatch repair gene(MMR).Colorectal hamartoma polyps with LKB1/STK11 mutations were larger in diameter than those with other gene mutations.

Charge compensation and capacity fading in LiCoO2 at high voltage investigated by soft x-ray absorption spectroscopy

In order to obtain an in-depth insight into the mechanism of charge compensation and capacity fading in LiCoO2, the evolution of electronic structure of LiCoO2 at different cutoff voltages and after different cycles are studied by soft x-ray absorption spectroscopy in total electron（TEY） and fluorescence（TFY） detection modes, which provide surface and bulk information, respectively. The spectra of Co L2,3-edge indicate that Co contributes to charge compensation below 4.4 V.Combining with the spectra of O K-edge, it manifests that only O contributes to electron compensation above 4.4 V with the formation of local O 2 p holes both on the surface and in the bulk, where the surficial O evolves more remarkably. The evolution of the O 2 p holes gives an explanation to the origin of O2^-or even O2. A comparison between the TEY and TFY of O K-edge spectra of LiCoO2 cycled in a range from 3 V to 4.6 V indicates both the structural change in the bulk and aggregation of lithium salts on the electrode surface are responsible for the capacity fading. However, the latter is found to play a more important role after many cycles.

Investigation on synergistic deposition of wax and hydrates in waxy water-in-oil(W/O) flow systems

Elucidating the synergistic effect of wax and hydrates, involving formation, aggregation and deposition,is imperative to the operation and transportation safety for offshore petroleum fields. To understand the characteristics and mechanism of synergistic deposition of wax and hydrates, flow and deposition experiments of systems with different wax contents(0-2.89 wt%), initial flow rates, pressures and temperatures were conducted in a high pressure visual flow loop. According to the flow rate and pressure drop data as well as the visual window observation, four different types of plugging scenarios of waxhydrate coexisting systems with different flow properties and wall deposition state were summarized,including rapid plugging, transition plugging, gradual plugging type I and gradual plugging type II.Compared with the wax-free system after hydrate formation, even with the addition of anti-agglomerant(AA) with the same concentration, wax-hydrate coexisting systems could not reach stable hydrate slurry flow state, indicating that the existence of wax deteriorated the performance of AA. Aside from the influence of wax crystals on hydrate agglomeration, it was found that wax deposition layer would alter the adhesion and bedding of hydrates, resulting in the variation of flow properties and wall deposition state.For low wax content systems(0.75 wt%) where rapid plugging occurred, the synergistic effect between wax and hydrates promoted the formation of wax-hydrate coupling aggregates, resulting in severe local deposition when the coupling aggregates attained critical deposition size and consequently decreasing flow rate, forming a vicious circle of decreasing transportability. Since bedding of coupling aggregates was hindered by the uniformly coated wax deposition layer on pipe wall, gradual plugging rather than rapid plugging occurred in medium wax content systems(1-1.25 wt%), predominately caused by the gradual increment in viscosity of waxy hydrate slurry. For relatively high wax content systems(2.89 wt%), hydrate formation and plugging did not occur, due to the insulation effect of wax deposition layer. A physical model for the synergistic deposition of wax and hydrates was also presented, which was meaningful to the development of a mathematical model for the prediction of blockage formation and risk analysis.

Diffuse invasive signet ring cell carcinoma in total colorectum caused by ulcerative colitis:A case report and review of literature

BACKGROUND Diffuse invasive signet ring cell carcinoma of the colorectum is extremely rare clinically.This type of colorectal cancer has certain clinical,pathological and biological characteristics that are different from ordinary colorectal cancer.CASE SUMMARY A 31-year-old young woman was admitted to the hospital for nearly 1 wk due to recurrent symptoms of mucopurulent bloody stools and abdominal distension.Preoperative colonoscopy showed a ring-shaped intestinal wall mass 10 cm from the rectum to the anus.Three pieces of tumor tissue were removed for examination.The pathological results showed rectal mucinous adenocarcinoma.The patient underwent laparoscopic exploration under general anesthesia,and then laparoscopic total colorectal resection,ileal pouch–anal anastomosis and ileostomy were performed.The patient was switched to a FOLFOX+cetuximab regimen.After the fifth cycle,the patient was unable to tolerate further treatment due to tumor progression and multiple organ dysfunction,and died at the end of May 2020.Overall survival was 7 mo.CONCLUSION Carcinogenesis of ulcerative colitis is different from sporadic colon cancer,and the overall prognosis is extremely poor.

Clinical Course and Outcome Patterns of Acute-on-chronic Liver Failure:A Multicenter Retrospective Cohort Study

Background and Aims:Acute-on-chronic liver failure(ACLF)is acute decompensation of liver function in the setting of chronic liver disease,and characterized by high short-term mortality.In this study,we sought to investigate the clinical course of patients at specific time points,and to propose dynamic prognostic criteria.Methods:We assessed the clinical course of 453 patients with ACLF during a 12-week follow-up period in this retrospective multicenter study.The clinical course of patients was defined as disease recovery,improvement,worsening or steady patterns based on the variation tendency in prothrombin activity(PTA)and total bilirubin(TB)at different time points.Results:Resolution of PTA was observed in 231 patients(51%)at 12 weeks after the diagnosis of ACLF.Among the remaining patients,66(14.6%)showed improvement and 156(34.4%)showed a steady or worsening course.In patients with resolved PTA,the clinical course of TB exhibited resolved pattern in 95.2%,improved in 3.9%,and steady or worse in 0.8%.Correspondingly,in patients with improved PTA,these values for TB were 28.8%,27.3%,and 43.9%,respectively.In patients with steady or worsening PTA,these values for TB were 5.7%,32.3%,and 65.6%,respectively.Dynamic prognostic criteria were developed by combining the clinical course of PTA/TB and the clinical outcomes at 4 and 12 weeks after diagnosis in ACLF patients.Conclusions:We propose the following dynamic prognostic criteria:rapid progression,slow progression,rapid recovery,slow recovery,and slow persistence,which lay the foundation for precise prediction of prognosis and the improvement of ACLF therapy.