CONSTANS(CO)and CONSTANS-LIKE(COL)transcription factors are known to regulate a series of cellular processes,including the transition from vegetative growth to flower development in plants.However,their role in regula...CONSTANS(CO)and CONSTANS-LIKE(COL)transcription factors are known to regulate a series of cellular processes,including the transition from vegetative growth to flower development in plants.However,their role in regulating the fruit chlorophyll content is poorly understood.In this study,SlCOL1,the tomato(Solanum lycopersicum)ortholog of Arabidopsis CONSTANS,was shown to play key roles in controlling fruit chlorophyll.The suppression of SlCOL1 expression led to a reduction in the chlorophyll content of immature green fruit,while the overexpression of SlCOL1 increased it.An analysis of protein-protein interactions indicated that SlCOL1 forms a complex with GOLDEN2-LIKE(GLK2),which promotes the stability of its protein.The overexpression of SlCOL1in the glk2 null mutation background of tomato failed to promote chlorophyll accumulation in the immature green fruit,which suggests that GLK2 is required for the function of SlCOL1 in regulating chlorophyll content.These results shed new light on the mechanisms used by COL1 and GLK2 to regulate fruit development and chlorophyll accumulation in tomato.展开更多
BACKGROUND Choledocholithiasis is a common benign disease of the biliary tract.We identified a particular type of choledocholithiasis characterized by sudden narrowing of the common bile duct at the site of impaction,...BACKGROUND Choledocholithiasis is a common benign disease of the biliary tract.We identified a particular type of choledocholithiasis characterized by sudden narrowing of the common bile duct at the site of impaction,which caused a marked increase in surgical difficulty and risk compared to treatment for typical choledocholithiasis.This phenomenon has not been described in previous studies.AIM To propose the ice-breaking sign and evaluate its influence on treatment strategies for choledocholithiasis.METHODS Using a retrospective case-control study design,patients who were diagnosed with common bile duct stones and admitted to the Emergency Department of Peking University Third Hospital between January 2018 and December 2023 were included.Propensity score matching was used to match cases and controls.Univariate analysis was conducted to assess the differences in clinical data between the two groups of patients.RESULTS There were no significant differences in the baseline data between the two groups,except for higher incidence of jaundice,alkaline phosphatase and total bilirubin in the ice-breaking sign group.Compared to the control group,the ice-breaking sign group had lower success rates for endoscopic retrograde cholangiopancreatography(25.0%vs 81.8%,P=0.006)and laparoscopic common bile duct exploration(69.4%vs 93.8%,P=0.007),longer operation time(148.04±60.55 minutes vs 106.15±35.21 minutes,P=0.001),higher likelihood of T-tube placement(62.2%vs 31.3%,P=0.016)and using lithotripsy techniques during surgery(29.7%vs 0%,P=0.001),more intraoperative bleeding[25.0(20.0-50.0)mL vs 10.0(10.0-20.0)mL,P<0.001]and longer postoperative hospital stay[6.50(5.0-9.0)days vs 5.50(3.0-6.50)days,P=0.002].The ice-breaking sign group showed significantly more dilatation in the proximal than distal bile duct.CONCLUSION The ice-breaking sign,a newly identified radiological phenomenon,may influence therapeutic decisions in choledocholithiasis,suggesting laparoscopic common bile duct exploration as the preferred approach over endoscopic retrograde cholangiopancreatography in patients exhibiting this sign.展开更多
AIM: To investigate the feasibility, efficacy and safety of laparoscopic hepaticoplasty using gallbladder as subcutaneous tunnel and sphincter-of-Oddi preservation for hepatolithiasis.
AIM: To evaluate the long-term outcomes of Oddi sphincter preserved cholangioplasty with hepaticosubcutaneous stoma(OSPCHS) and risk factors for recurrence in hepatolithiasis.METHODS: From March 1993 to December 2012,...AIM: To evaluate the long-term outcomes of Oddi sphincter preserved cholangioplasty with hepaticosubcutaneous stoma(OSPCHS) and risk factors for recurrence in hepatolithiasis.METHODS: From March 1993 to December 2012, 202 consecutive patients with hepatolithiasis underwent OSPCHS at our department. The Oddi sphincter preserved procedure consisted of common hepatic duct exploration, stone extraction, hilar bile duct plasty, establishment of subcutaneous stoma to the bile duct. Patients with recurrent stones can undergo stone extraction and/or biliary drainage via the subcutaneous stoma which can be incised under local anesthesia. The long-term results were reviewed. Cox regression model was employed to analyze the risk factors for stone recurrence.RESULTS: Ninety-seven(48.0%) OSPCHS patients underwent hepatic resection concomitantly. The rate of surgical complications was 10.4%. There was no perioperative death. The immediate stone clearance rate was 72.8%. Postoperative cholangioscopic lithotomy raised the clearance rate to 97.0%. With a median follow-up period of 78.5 mo(range: 2-233 mo), 24.8% of patients had recurrent stones, 2.5% had late development of cholangiocarcinoma, and the mortality rate was 5.4%. Removal of recurrent stones and/or drainage of inflammatory bile via subcutaneous stoma were conducted in 44(21.8%) patients. The clearance rate of recurrent stones was 84.0% after subsequent choledochoscopic lithotripsy via subcutaneous stoma.Cox regression analysis showed that residual stone was an independent prognostic factor for stone recurrence.CONCLUSION: In selected patients with hepatolithiasis, OSPCHS achieves excellent long-term outcomes, and residual stone is an independent prognostic factor for stone recurrence.展开更多
OBJECTIVE: To evaluate the killing effects of the cytosine deaminase (CD) gene mediated by adenovirus vector on human pancreatic cancer cell lines in vitro. METHODS: The CD gene was cloned into pAdTrack-CMV-CD, and pA...OBJECTIVE: To evaluate the killing effects of the cytosine deaminase (CD) gene mediated by adenovirus vector on human pancreatic cancer cell lines in vitro. METHODS: The CD gene was cloned into pAdTrack-CMV-CD, and pAdTrack-CMV-CD and pAdEasy-l were recombinated in bacteria. The newly recombinated Ad-CD containing green fluoreseent protein (GFP) was propagated in 293 cells and purified by cesium chloride gradient centrifugation. Human pancreatic cancer cell lines Patu8988 and SW1990 were infected with this virus, then 5-FC was added. XTT assay was used to estimate relative numbers of viable cells. RESULTS: The positive clones were selected by using endonuclease to digest the combinatants and the concentration of viral liquids containing the CD gene was 2×1O^(11) pfu/ml. It was found that significant cytotoxic activities were possesscd by 5-FC for the CD gene transduced pancreatic cell lines, but little effects exerted on the nontransduced pancreatic carcinoma cells. CONCLUSIONS: The CD gene mediated by adenovirus with a high infectivity is efficient for gene therapy of pancreatic carcinoma cell lines. These data demonstrate the therapeutic efficacy of an enzyme prodrug strategy in experimental pancreatic cancer.展开更多
Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment mon...Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols).展开更多
AIM： To establish if PTCHla transcriptional regulation region （TRR） is methylated in gastric cancer and its influence in gastric tumorigenesis.METHODS： The CpG islands in PTCHla TRR were analyzed by Methyl Primer ...AIM： To establish if PTCHla transcriptional regulation region （TRR） is methylated in gastric cancer and its influence in gastric tumorigenesis.METHODS： The CpG islands in PTCHla TRR were analyzed by Methyl Primer Express v1.0 software. The region from -643 to -355 bp （the transcription initiation site of PTCHla was designated as 0） that contained 19 CpG sites was chosen for bisulfitesequencing PCR （BSP） and methylation-specific PCR （MSP） detection. The gastric cancer cell line AGS was treated with 5-aza-2′-deoxycytidine （5-Aza-dC; 1 μmol/L） for 3 d. Alterations in PTCHla TRR methylation in treated AGS cells was measured through BSP clone sequences, and their PTCH1 expression was measured by quantitative RT-PCR. The cell cycle and apoptosis were observed with flow cytometry through propidium iodide （PI） staining or annexin V/PI double staining. The prevalence of PTCHla TRR methylation was investigated in 170 gastric cancer tissue samples and the adjacent normal tissues by MSP. The correlation of PTCH1a TRR methylation with PTCH1 expression or with patients＇ clinical features was analyzed.RESULTS： Methylation of PTCHla TRR was observed in AGS ceils and a subset of gastric cancer tissues （32%, 55/170）, while no methylation amplification products were observed in any normal tissues by MSP. The methylation of PTCH1α TRR was correlated negatively with PTCH1 expression （Spearman＇s r = -0.380, P = 0.000）. However, methylation of PTCHla TRR was not related to the gastric cancer patients＇ clinical features, such as sex, age of onset, clinical stage, lymph node metastasis or histological grade. The methylation of PTCHla TRR in AGS cells was almost converted to non-methylation after 5-Aza-dC treatment, which increased PTCH1 expression （5.3 ± 2.5 times; n = 3） and apoptosis rate （3.0 ± 0.26 times; P 〈 0.05; n = 3）.CONCLUSION： Methylation of PTCH1α TRR is present in a subset of gastric cancers and correlated negatively with PTCH1 expression. This may be an early event in gastric tumorigenesis and a new treatment target.展开更多
Monitoring of ambient volatile organic compounds(VOCs)was conducted within typical residentialcommercial area in the city of Xi’an in northwest China during typical ozone(O_(3))episodes,to investigate the major contr...Monitoring of ambient volatile organic compounds(VOCs)was conducted within typical residentialcommercial area in the city of Xi’an in northwest China during typical ozone(O_(3))episodes,to investigate the major contributors to the characteristic of ambient VOCs and their impact on O_(3) production.In the residential-commercial area,diurnal variation of VOCs was highly impacted by vehicle exhaust,fuel evaporation,and local solvent use.Relative higher contributions(up to 60%)of VOCs from solvent use to the ozone formation potential were found.The present findings highlight the urgent need for restrictions on the emission of VOCs from solvent use and non-vehicle-traffic-related sources,such as oil storage.展开更多
AIM:To investigate the relationship and molecular features of CD74/macrophage migration inhibitory factor(MIF)/Toll-like receptor 4(TLR4) in gastric cancer.METHODS:CD74,MIF and TLR4 expression in the paraffin-embedded...AIM:To investigate the relationship and molecular features of CD74/macrophage migration inhibitory factor(MIF)/Toll-like receptor 4(TLR4) in gastric cancer.METHODS:CD74,MIF and TLR4 expression in the paraffin-embedded sections of gastric cancer from 120 patients were detected by immunohistochemical staining.Knock down of CD74 expression in gastric cancer cell line MKN-45 was performed by lentivirus transduction and detected by Western blotting.MKN-45 cell proliferation assay under the stimulants was measured by the cell counting kit 8(CCK8) assay and MIF concentration in the culture medium was detected by enzymelinked immunosorbent assay.Surface staining of CD74 in the MKN-45 cell line under the stimulation of lipopolysaccharide(LPS) was measured by flow cytometry.MIF,CD74 and TLR4 co-localization in the MKN-45 cell line was performed by the immunoprecipitation.RESULTS:CD74,MIF and TLR4 were found to be expressed in gastric cancer and increased significantly in the advanced stage,and were also associated with lymph node metastasis.Correlation analysis revealed that CD74 was positively correlated with MIF(r = 0.2367,P < 0.01) and both proteins were also associated with TLR4(r = 0.4414,r = 0.5001,respectively,P < 0.01).LPS can significantly promote MKN-45 cell proliferation(3.027 ± 0.388 vs 4.201 ± 0.092,P < 0.05),induce MIF production(54.333 ± 2.906 pg/mL vs 29.667 ± 3.180 pg/mL,P < 0.01) and cell surface expression of CD74(75.6% ± 4.046%vs 9.4% ± 0.964%,P < 0.01) at LPS concentration of 1 μg/mL compared to medium control.Knockdown of CD74 or using antiCD74 and MIF antagonist ISO-1 significantly reduced LPS-induced MKN-45 cell proliferation(4.201 ± 0.092 vs 3.337 ± 0.087,4.534 ± 0.222 vs 3.368 ± 0.290,4.058 ± 0.292vs 2.934 ± 0.197,respectively,P < 0.01).MIF,CD74 and TLR4 could co-localize in the MKN-45 cell line.CONCLUSION:Upregulation of MIF,CD74 and TLR4 are associated with increasing clinical stage and provide an opportunity as novel gastric cancer chemoprevention and/or treatment strategy.展开更多
Rare earth catalysts possessing characteristics of cation-anion ion pair show advantages of adjusting electronegativity and steric hindrance of metal active sites, which can control the catalytic performance and stere...Rare earth catalysts possessing characteristics of cation-anion ion pair show advantages of adjusting electronegativity and steric hindrance of metal active sites, which can control the catalytic performance and stereoselectivity better than those of traditional metallocene and Ziegler-Natta catalysts in diene polymerization. In this work, a series of neodymium organic sulfonate complexes,Nd(CF_3SO_3)_3·x H_2O·y L(x, y: the coordination number; L refers to an organic electron donating ligand, such as acetylacetone(acac), isooctyl alcohol(IAOH), tributyl phosphate(TBP), etc.), have been synthesized to form the cationic active species in the presence of alkylaluminum such as Al(i-Bu)_3, AlEt_3, and Al(i-Bu)_2H, which display high activities and distinguishing cis-1,4 selectivities(up to99.9%) for the polymerization of butadiene. The microstructures, yield, molecular weight, and molecular weight distribution of the resulting polymer are well controlled by adjusting electronegativity/steric hindrance of the complexes. In addition, the kinetics, active species, and the possible process of polymerization are also discussed in this article.展开更多
Hilar cholangiocarcinoma(HCCA)(also known as Klatskin tumor)has a poor prognosis worldwide,and accounts for more than half of cholangiocarcinoma cases.HCCA originates from epithelium and often arises from the confluen...Hilar cholangiocarcinoma(HCCA)(also known as Klatskin tumor)has a poor prognosis worldwide,and accounts for more than half of cholangiocarcinoma cases.HCCA originates from epithelium and often arises from the confluence of the bile ducts or the right or left hepatic ducts[1,2].Because of its aggressiveness and refractory biological characteristics,the median survival time of patients with unresectable HCCA is less than 1 year.Radical resection is the most effective treatment for HCCA.展开更多
People spend the majority of their time indoors. Indoor airborne microorganisms, comprised of airborne particles containing fungi, bacteria, and virus present a significant concern in household environment due to thei...People spend the majority of their time indoors. Indoor airborne microorganisms, comprised of airborne particles containing fungi, bacteria, and virus present a significant concern in household environment due to their potential implications for indoor air quality and human health. This review synthesizes recent advancements in the fields of indoor air quality science, microbiology, and environmental engineering, providing insights into the sources, concentrations, transmission, influencing factors and control technology of indoor airborne microorganisms in residential environments. Factors such as occupant activities, pets, indoor temperature, humidity, and ventilation systems are critical in shaping the patterns and quantities of these microorganisms.展开更多
Background Total proctocolectomy with ileal pouch–anal anastomosis(IPAA)was the first choice for the surgical treatment of the ulcerative colitis(UC)patients.The data on the predictive value of the ulcerative colitis...Background Total proctocolectomy with ileal pouch–anal anastomosis(IPAA)was the first choice for the surgical treatment of the ulcerative colitis(UC)patients.The data on the predictive value of the ulcerative colitis endoscopic index of severity(UCEIS)for the need for IPAA in UC patients is scarce.We aimed to establish the UCEIS cut-off value to further analyse whether the UCEIS cut-off was suitable for predicting the need for IPAA in UC patients.Methods The clinical data of UC patients from June 1986 to March 2020 at our institute were retrospectively assessed.The UCEIS scores recorded at the time of the first colonoscopy after hospitalization were used in the study.Receiver operating characteristic curve analysis was performed to determine the UCEIS cut-off value for predicting the need for IPAA.Results A total of 283 UC patients were included in the study,with a median UCEIS of 4.During a median follow-up of 13 years,80 patients(28.3%)received surgery invention,among whom 75(93.8%)underwent IPAA surgery and 5(6.2%)received subtotal colectomy with permanent ostomy.A UCEIS cut-off of 6 had the most significant area under the curve of 0.769 for predicting the need for IPAA(P<0.001),with a sensitivity of 72.0%and specificity of 81.8%.UCEIS≥6 was an independent predictive factor for the need for IPAA(P<0.001)and malignant transformation(P=0.010).Patients with UCEIS≥6 had a significantly shorter IPAA-free survival time than those with UCEIS<6(P<0.001).Conclusions UCEIS≥6 may be a threshold value for decision-making for IPAA and should be recommended for UC patients for reducing the incidence of malignant transformation.展开更多
Background:Lgr5-positive cells located in the basal layer of crypts have self-regenerative and proliferative differentiation potentials of intestinal stem cells(ISCs),maintaining a balance of regeneration-repair in mu...Background:Lgr5-positive cells located in the basal layer of crypts have self-regenerative and proliferative differentiation potentials of intestinal stem cells(ISCs),maintaining a balance of regeneration-repair in mucosal epithelium.However,the mechanisms of mucosal repair that are regulated by ISCs in ulcerative colitis(UC)remain unclear.Method:Colon tissues from patients with UC were collected to testβ-catenin and Notch1 expression by using Western blot and quantitative real-time polymerase chain reaction(PCR).β-catenin^(fl/fl) mice,β-cateninTg mice,and Dll1tm1 Gos mice were used to cross with Lgr5-EGFP-IRES-creERT2 mice to generate mice of different genotypes,altering the activation of Wnt/β-catenin and Dll1-mediated Notch signaling in ISCs in vivo.Dextran sulfate sodium(DSS)was used to induce a colitis mice model.Intestinal organoids were isolated and cultured to observe the proliferation and differentiation levels of ISCs.Result:β-catenin and Notch1 expression were significantly increased in the inflamed colon tissues from patients with UC.Wnt/β-catenin activation and Dll1-mediated Notch pathway inhibition in Lgr5-positive stem cells promoted the expressions of E-cadherin,CK20,and CHGA in colonic organoids and epithelium,implying the promotion of colonic epithelial integrity.Activation of Wnt/β-catenin and suppression of Dll1-mediated Notch pathway in Lgr5-positive ISCs alleviated the DSS-induced intestinal mucosal inflammation in mice.Conclusions:Lgr5-positive ISCs are characterized by self-renewal and high dividend potential,which play an important role in the injury and repair of intestinal mucosa.More importantly,the Wnt/β-catenin signaling pathway cooperates with the Notch signaling pathway to maintain the function of the Lgr5-positive ISCs.展开更多
微型仿生机器人是一种仿照生物外形和运动形态制作设计的机器人,凭借其体型小、机动性高、环境适应性强等优点,在复杂环境探索、敌情侦察等特殊场景中具有较高的应用前景,近年来备受研究人员的关注.但是微型机器人运动稳定性弱、单目相...微型仿生机器人是一种仿照生物外形和运动形态制作设计的机器人,凭借其体型小、机动性高、环境适应性强等优点,在复杂环境探索、敌情侦察等特殊场景中具有较高的应用前景,近年来备受研究人员的关注.但是微型机器人运动稳定性弱、单目相机环境感知精度低等问题的存在一直制约着其实际应用.本文仿照昆虫“独角仙”设计了一种新的微型仿生爬虫机器人,开发了基于生物运动调控机制的六足机器人控制系统,改进了基于啮齿类动物空间导航原理的同时定位与建图系统.使用自研的微型仿生爬虫机器人在人造沙盘和真实室内走廊两个场景中进行了实验验证.在人造沙盘场景,由于微型仿生爬虫机器人提供的环境图像质量模糊,ORB-SLAM3算法无法完成回环检测,不能正确识别曾经见过的场景.类脑同步定位与地图构建(simultaneous localization and mapping,SLAM)系统回环准确率高达100%,比原RatSLAM算法提高了4.36%.在真实室内走廊场景,ORB-SLAM3算法和RatSLAM算法建图效果都比较差,而类脑SLAM不仅有着较好的建图结果,而且在准确率100%的同时召回率也高达97.87%.与ORB-SLAM3和RatSLAM算法相比,类脑SLAM系统取得了较好的建图结果.因此,自研的微型仿生爬虫机器人具有灵活的运动能力、鲁棒的导航定位能力,促使微型仿生机器人离实际应用更近了一步.展开更多
Xenorhabdus nematophila, a Gram-negative proteobacterium belonging to the family Enterobacteriaceae and associated symbiotically with soil entomopathogenic nematodes, Steinernema carpocapsae, is pathogenic to a wide r...Xenorhabdus nematophila, a Gram-negative proteobacterium belonging to the family Enterobacteriaceae and associated symbiotically with soil entomopathogenic nematodes, Steinernema carpocapsae, is pathogenic to a wide range of insects. A protein complex with insecticidal activity was isolated from the cells ofX. nematophila HB310 strain using methods of salting out and native polyacrylamide gel electrophoresis （PAGE）. Seven polypeptides ranging 50~250 kDa were well separated from the protein complex （named Xnpt） by sodium dodecyl sulfate （SDS）-PAGE, five of which are identified as XptA2, xptC 1, XptB 1, GroEL and hypothetical protein by matrix-assisted laser desorption- time-of-flight mass spectrometry （MALDI-TOFMS）. Xnpt showed high oral virulence to larvae of diamondback moth （DBM）, Plutella xylostella L. （Lepidoptera, Plutellidae） as its median lethal concentration （LC50） against second and third instar larvae were 331.45 ng/mL and 553.59 ng/mL at 72 h, respectively. The histological analysis of Xnptfed DBM larvae showed extensive histopathological effects on the midgut. Biochemical analysis indicated that Xnpt markedly inhibited the activities of three important enzymes in the midgut. Overall, our data showed that the protein complex isolated from X. nematophila HB310 induced the antifeedant and death of insects by destroying midgut tissues and inhibiting midgut proteases activities.展开更多
基金supported by grants from the National Natural Science Foundation of China(32360766,32072595 and 32202512)the Earmarked Fund for CARS(CARS-23-A13)。
文摘CONSTANS(CO)and CONSTANS-LIKE(COL)transcription factors are known to regulate a series of cellular processes,including the transition from vegetative growth to flower development in plants.However,their role in regulating the fruit chlorophyll content is poorly understood.In this study,SlCOL1,the tomato(Solanum lycopersicum)ortholog of Arabidopsis CONSTANS,was shown to play key roles in controlling fruit chlorophyll.The suppression of SlCOL1 expression led to a reduction in the chlorophyll content of immature green fruit,while the overexpression of SlCOL1 increased it.An analysis of protein-protein interactions indicated that SlCOL1 forms a complex with GOLDEN2-LIKE(GLK2),which promotes the stability of its protein.The overexpression of SlCOL1in the glk2 null mutation background of tomato failed to promote chlorophyll accumulation in the immature green fruit,which suggests that GLK2 is required for the function of SlCOL1 in regulating chlorophyll content.These results shed new light on the mechanisms used by COL1 and GLK2 to regulate fruit development and chlorophyll accumulation in tomato.
基金Supported by Clinical Cohort Construction Program of Peking University Third Hospital,No.BYSYDL2023005Peking University Third Hospital Innovation Transformation Fund,No.BYSYZHZB2023105.
文摘BACKGROUND Choledocholithiasis is a common benign disease of the biliary tract.We identified a particular type of choledocholithiasis characterized by sudden narrowing of the common bile duct at the site of impaction,which caused a marked increase in surgical difficulty and risk compared to treatment for typical choledocholithiasis.This phenomenon has not been described in previous studies.AIM To propose the ice-breaking sign and evaluate its influence on treatment strategies for choledocholithiasis.METHODS Using a retrospective case-control study design,patients who were diagnosed with common bile duct stones and admitted to the Emergency Department of Peking University Third Hospital between January 2018 and December 2023 were included.Propensity score matching was used to match cases and controls.Univariate analysis was conducted to assess the differences in clinical data between the two groups of patients.RESULTS There were no significant differences in the baseline data between the two groups,except for higher incidence of jaundice,alkaline phosphatase and total bilirubin in the ice-breaking sign group.Compared to the control group,the ice-breaking sign group had lower success rates for endoscopic retrograde cholangiopancreatography(25.0%vs 81.8%,P=0.006)and laparoscopic common bile duct exploration(69.4%vs 93.8%,P=0.007),longer operation time(148.04±60.55 minutes vs 106.15±35.21 minutes,P=0.001),higher likelihood of T-tube placement(62.2%vs 31.3%,P=0.016)and using lithotripsy techniques during surgery(29.7%vs 0%,P=0.001),more intraoperative bleeding[25.0(20.0-50.0)mL vs 10.0(10.0-20.0)mL,P<0.001]and longer postoperative hospital stay[6.50(5.0-9.0)days vs 5.50(3.0-6.50)days,P=0.002].The ice-breaking sign group showed significantly more dilatation in the proximal than distal bile duct.CONCLUSION The ice-breaking sign,a newly identified radiological phenomenon,may influence therapeutic decisions in choledocholithiasis,suggesting laparoscopic common bile duct exploration as the preferred approach over endoscopic retrograde cholangiopancreatography in patients exhibiting this sign.
文摘AIM: To investigate the feasibility, efficacy and safety of laparoscopic hepaticoplasty using gallbladder as subcutaneous tunnel and sphincter-of-Oddi preservation for hepatolithiasis.
文摘AIM: To evaluate the long-term outcomes of Oddi sphincter preserved cholangioplasty with hepaticosubcutaneous stoma(OSPCHS) and risk factors for recurrence in hepatolithiasis.METHODS: From March 1993 to December 2012, 202 consecutive patients with hepatolithiasis underwent OSPCHS at our department. The Oddi sphincter preserved procedure consisted of common hepatic duct exploration, stone extraction, hilar bile duct plasty, establishment of subcutaneous stoma to the bile duct. Patients with recurrent stones can undergo stone extraction and/or biliary drainage via the subcutaneous stoma which can be incised under local anesthesia. The long-term results were reviewed. Cox regression model was employed to analyze the risk factors for stone recurrence.RESULTS: Ninety-seven(48.0%) OSPCHS patients underwent hepatic resection concomitantly. The rate of surgical complications was 10.4%. There was no perioperative death. The immediate stone clearance rate was 72.8%. Postoperative cholangioscopic lithotomy raised the clearance rate to 97.0%. With a median follow-up period of 78.5 mo(range: 2-233 mo), 24.8% of patients had recurrent stones, 2.5% had late development of cholangiocarcinoma, and the mortality rate was 5.4%. Removal of recurrent stones and/or drainage of inflammatory bile via subcutaneous stoma were conducted in 44(21.8%) patients. The clearance rate of recurrent stones was 84.0% after subsequent choledochoscopic lithotripsy via subcutaneous stoma.Cox regression analysis showed that residual stone was an independent prognostic factor for stone recurrence.CONCLUSION: In selected patients with hepatolithiasis, OSPCHS achieves excellent long-term outcomes, and residual stone is an independent prognostic factor for stone recurrence.
基金This work was supported by a grant from Shanghai Science Foundation (No. 994119044).
文摘OBJECTIVE: To evaluate the killing effects of the cytosine deaminase (CD) gene mediated by adenovirus vector on human pancreatic cancer cell lines in vitro. METHODS: The CD gene was cloned into pAdTrack-CMV-CD, and pAdTrack-CMV-CD and pAdEasy-l were recombinated in bacteria. The newly recombinated Ad-CD containing green fluoreseent protein (GFP) was propagated in 293 cells and purified by cesium chloride gradient centrifugation. Human pancreatic cancer cell lines Patu8988 and SW1990 were infected with this virus, then 5-FC was added. XTT assay was used to estimate relative numbers of viable cells. RESULTS: The positive clones were selected by using endonuclease to digest the combinatants and the concentration of viral liquids containing the CD gene was 2×1O^(11) pfu/ml. It was found that significant cytotoxic activities were possesscd by 5-FC for the CD gene transduced pancreatic cell lines, but little effects exerted on the nontransduced pancreatic carcinoma cells. CONCLUSIONS: The CD gene mediated by adenovirus with a high infectivity is efficient for gene therapy of pancreatic carcinoma cell lines. These data demonstrate the therapeutic efficacy of an enzyme prodrug strategy in experimental pancreatic cancer.
基金This research was supported by the Natural Science Foundation of China(Grant No.41907188)Natural Science Foundation of Shaanxi Province,China(Grant No.2019JQ-386)the China Postdoctoral Science Foundation(Grant No.2019M653658).
文摘Summer and winter campaigns for the chemical compositions and sources of nonmethane hydrocarbons(NMHCs)and oxygenated volatile organic compounds(OVOCs)were conducted in Xi’an.Data from 57 photochemical assessment monitoring stations for NMHCs and 20 OVOC species were analyzed.Significant seasonal differences were noted for total VOC(TVOC,NMHCs and OVOCs)concentrations and compositions.The campaign-average TVOC concentrations in winter(85.3±60.6 ppbv)were almost twice those in summer(47.2±31.6 ppbv).Alkanes and OVOCs were the most abundant category in winter and summer,respectively.NMHCs,but not OVOCs,had significantly higher levels on weekends than on weekdays.Total ozone formation potential was higher in summer than in winter(by 50%)because of the high concentrations of alkenes(particularly isoprene),high temperature,and high solar radiation levels in summer.The Hybrid Environmental Receptor Model(HERM)was used to conduct source apportionment for atmospheric TVOCs in winter and summer,with excellent accuracy.HERM demonstrated its suitability in a situation where only partial source profile data were available.The HERM results indicated significantly different seasonal source contributions to TVOCs in Xi’an.In particular,coal and biomass burning had contributions greater than half in winter(53.4%),whereas traffic sources were prevalent in summer(53.1%).This study’s results highlight the need for targeted and adjustable VOC control measures that account for seasonal differences in Xi’an;such measures should target not only the severe problem with VOC pollution but also the problem of consequent secondary pollution(e.g.,from ozone and secondary organic aerosols).
基金Supported by City Hospital Trust Fund and the University of Birmingham Scientific Project Grant
文摘AIM： To establish if PTCHla transcriptional regulation region （TRR） is methylated in gastric cancer and its influence in gastric tumorigenesis.METHODS： The CpG islands in PTCHla TRR were analyzed by Methyl Primer Express v1.0 software. The region from -643 to -355 bp （the transcription initiation site of PTCHla was designated as 0） that contained 19 CpG sites was chosen for bisulfitesequencing PCR （BSP） and methylation-specific PCR （MSP） detection. The gastric cancer cell line AGS was treated with 5-aza-2′-deoxycytidine （5-Aza-dC; 1 μmol/L） for 3 d. Alterations in PTCHla TRR methylation in treated AGS cells was measured through BSP clone sequences, and their PTCH1 expression was measured by quantitative RT-PCR. The cell cycle and apoptosis were observed with flow cytometry through propidium iodide （PI） staining or annexin V/PI double staining. The prevalence of PTCHla TRR methylation was investigated in 170 gastric cancer tissue samples and the adjacent normal tissues by MSP. The correlation of PTCH1a TRR methylation with PTCH1 expression or with patients＇ clinical features was analyzed.RESULTS： Methylation of PTCHla TRR was observed in AGS ceils and a subset of gastric cancer tissues （32%, 55/170）, while no methylation amplification products were observed in any normal tissues by MSP. The methylation of PTCH1α TRR was correlated negatively with PTCH1 expression （Spearman＇s r = -0.380, P = 0.000）. However, methylation of PTCHla TRR was not related to the gastric cancer patients＇ clinical features, such as sex, age of onset, clinical stage, lymph node metastasis or histological grade. The methylation of PTCHla TRR in AGS cells was almost converted to non-methylation after 5-Aza-dC treatment, which increased PTCH1 expression （5.3 ± 2.5 times; n = 3） and apoptosis rate （3.0 ± 0.26 times; P 〈 0.05; n = 3）.CONCLUSION： Methylation of PTCH1α TRR is present in a subset of gastric cancers and correlated negatively with PTCH1 expression. This may be an early event in gastric tumorigenesis and a new treatment target.
基金supported by the National Key Research and Development Program of China(Nos.2017YFC0212200 and 2016YFA0203000)the National Natural Science Foundation of China(Nos.41701565 and 41877308)the Chinese Academy of Sciences“Light of West China”Program(No.XAB2019B06).
文摘Monitoring of ambient volatile organic compounds(VOCs)was conducted within typical residentialcommercial area in the city of Xi’an in northwest China during typical ozone(O_(3))episodes,to investigate the major contributors to the characteristic of ambient VOCs and their impact on O_(3) production.In the residential-commercial area,diurnal variation of VOCs was highly impacted by vehicle exhaust,fuel evaporation,and local solvent use.Relative higher contributions(up to 60%)of VOCs from solvent use to the ozone formation potential were found.The present findings highlight the urgent need for restrictions on the emission of VOCs from solvent use and non-vehicle-traffic-related sources,such as oil storage.
基金Supported by Shanghai Municipal Natural Science Foundation, No.09DZ1907203 and No.10411950400National Natural Science Foundation of China,No.81072009
文摘AIM:To investigate the relationship and molecular features of CD74/macrophage migration inhibitory factor(MIF)/Toll-like receptor 4(TLR4) in gastric cancer.METHODS:CD74,MIF and TLR4 expression in the paraffin-embedded sections of gastric cancer from 120 patients were detected by immunohistochemical staining.Knock down of CD74 expression in gastric cancer cell line MKN-45 was performed by lentivirus transduction and detected by Western blotting.MKN-45 cell proliferation assay under the stimulants was measured by the cell counting kit 8(CCK8) assay and MIF concentration in the culture medium was detected by enzymelinked immunosorbent assay.Surface staining of CD74 in the MKN-45 cell line under the stimulation of lipopolysaccharide(LPS) was measured by flow cytometry.MIF,CD74 and TLR4 co-localization in the MKN-45 cell line was performed by the immunoprecipitation.RESULTS:CD74,MIF and TLR4 were found to be expressed in gastric cancer and increased significantly in the advanced stage,and were also associated with lymph node metastasis.Correlation analysis revealed that CD74 was positively correlated with MIF(r = 0.2367,P < 0.01) and both proteins were also associated with TLR4(r = 0.4414,r = 0.5001,respectively,P < 0.01).LPS can significantly promote MKN-45 cell proliferation(3.027 ± 0.388 vs 4.201 ± 0.092,P < 0.05),induce MIF production(54.333 ± 2.906 pg/mL vs 29.667 ± 3.180 pg/mL,P < 0.01) and cell surface expression of CD74(75.6% ± 4.046%vs 9.4% ± 0.964%,P < 0.01) at LPS concentration of 1 μg/mL compared to medium control.Knockdown of CD74 or using antiCD74 and MIF antagonist ISO-1 significantly reduced LPS-induced MKN-45 cell proliferation(4.201 ± 0.092 vs 3.337 ± 0.087,4.534 ± 0.222 vs 3.368 ± 0.290,4.058 ± 0.292vs 2.934 ± 0.197,respectively,P < 0.01).MIF,CD74 and TLR4 could co-localize in the MKN-45 cell line.CONCLUSION:Upregulation of MIF,CD74 and TLR4 are associated with increasing clinical stage and provide an opportunity as novel gastric cancer chemoprevention and/or treatment strategy.
基金the National Natural Science Foundation of China(Nos.51473156 and 51873203)Key Projects of Jilin Province Science and Technology Development Plan(Nos.2018020108GX and 20160204028GX)
文摘Rare earth catalysts possessing characteristics of cation-anion ion pair show advantages of adjusting electronegativity and steric hindrance of metal active sites, which can control the catalytic performance and stereoselectivity better than those of traditional metallocene and Ziegler-Natta catalysts in diene polymerization. In this work, a series of neodymium organic sulfonate complexes,Nd(CF_3SO_3)_3·x H_2O·y L(x, y: the coordination number; L refers to an organic electron donating ligand, such as acetylacetone(acac), isooctyl alcohol(IAOH), tributyl phosphate(TBP), etc.), have been synthesized to form the cationic active species in the presence of alkylaluminum such as Al(i-Bu)_3, AlEt_3, and Al(i-Bu)_2H, which display high activities and distinguishing cis-1,4 selectivities(up to99.9%) for the polymerization of butadiene. The microstructures, yield, molecular weight, and molecular weight distribution of the resulting polymer are well controlled by adjusting electronegativity/steric hindrance of the complexes. In addition, the kinetics, active species, and the possible process of polymerization are also discussed in this article.
基金This study was supported by a grant from the Xuzhou Science and Technology Project(KC19192).
文摘Hilar cholangiocarcinoma(HCCA)(also known as Klatskin tumor)has a poor prognosis worldwide,and accounts for more than half of cholangiocarcinoma cases.HCCA originates from epithelium and often arises from the confluence of the bile ducts or the right or left hepatic ducts[1,2].Because of its aggressiveness and refractory biological characteristics,the median survival time of patients with unresectable HCCA is less than 1 year.Radical resection is the most effective treatment for HCCA.
基金This work was financially supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences(grant No.2022415)the Natural Science Foundation of Shaanxi Province,China(grant No.2022JQ-518)+1 种基金the Youth Cross Team Scientific Research Project of the Chinese Academy of Sciences(grant No.JCTD-2022-17)National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain,Shaanxi,China.
文摘People spend the majority of their time indoors. Indoor airborne microorganisms, comprised of airborne particles containing fungi, bacteria, and virus present a significant concern in household environment due to their potential implications for indoor air quality and human health. This review synthesizes recent advancements in the fields of indoor air quality science, microbiology, and environmental engineering, providing insights into the sources, concentrations, transmission, influencing factors and control technology of indoor airborne microorganisms in residential environments. Factors such as occupant activities, pets, indoor temperature, humidity, and ventilation systems are critical in shaping the patterns and quantities of these microorganisms.
基金supported by the National Natural Science Foundation of China[No.82000481]the Shanghai Sailing Program[No.20YF1429400].
文摘Background Total proctocolectomy with ileal pouch–anal anastomosis(IPAA)was the first choice for the surgical treatment of the ulcerative colitis(UC)patients.The data on the predictive value of the ulcerative colitis endoscopic index of severity(UCEIS)for the need for IPAA in UC patients is scarce.We aimed to establish the UCEIS cut-off value to further analyse whether the UCEIS cut-off was suitable for predicting the need for IPAA in UC patients.Methods The clinical data of UC patients from June 1986 to March 2020 at our institute were retrospectively assessed.The UCEIS scores recorded at the time of the first colonoscopy after hospitalization were used in the study.Receiver operating characteristic curve analysis was performed to determine the UCEIS cut-off value for predicting the need for IPAA.Results A total of 283 UC patients were included in the study,with a median UCEIS of 4.During a median follow-up of 13 years,80 patients(28.3%)received surgery invention,among whom 75(93.8%)underwent IPAA surgery and 5(6.2%)received subtotal colectomy with permanent ostomy.A UCEIS cut-off of 6 had the most significant area under the curve of 0.769 for predicting the need for IPAA(P<0.001),with a sensitivity of 72.0%and specificity of 81.8%.UCEIS≥6 was an independent predictive factor for the need for IPAA(P<0.001)and malignant transformation(P=0.010).Patients with UCEIS≥6 had a significantly shorter IPAA-free survival time than those with UCEIS<6(P<0.001).Conclusions UCEIS≥6 may be a threshold value for decision-making for IPAA and should be recommended for UC patients for reducing the incidence of malignant transformation.
基金supported by the National Natural Science Foundation of China[No.82000481,81570474,and 82270549].
文摘Background:Lgr5-positive cells located in the basal layer of crypts have self-regenerative and proliferative differentiation potentials of intestinal stem cells(ISCs),maintaining a balance of regeneration-repair in mucosal epithelium.However,the mechanisms of mucosal repair that are regulated by ISCs in ulcerative colitis(UC)remain unclear.Method:Colon tissues from patients with UC were collected to testβ-catenin and Notch1 expression by using Western blot and quantitative real-time polymerase chain reaction(PCR).β-catenin^(fl/fl) mice,β-cateninTg mice,and Dll1tm1 Gos mice were used to cross with Lgr5-EGFP-IRES-creERT2 mice to generate mice of different genotypes,altering the activation of Wnt/β-catenin and Dll1-mediated Notch signaling in ISCs in vivo.Dextran sulfate sodium(DSS)was used to induce a colitis mice model.Intestinal organoids were isolated and cultured to observe the proliferation and differentiation levels of ISCs.Result:β-catenin and Notch1 expression were significantly increased in the inflamed colon tissues from patients with UC.Wnt/β-catenin activation and Dll1-mediated Notch pathway inhibition in Lgr5-positive stem cells promoted the expressions of E-cadherin,CK20,and CHGA in colonic organoids and epithelium,implying the promotion of colonic epithelial integrity.Activation of Wnt/β-catenin and suppression of Dll1-mediated Notch pathway in Lgr5-positive ISCs alleviated the DSS-induced intestinal mucosal inflammation in mice.Conclusions:Lgr5-positive ISCs are characterized by self-renewal and high dividend potential,which play an important role in the injury and repair of intestinal mucosa.More importantly,the Wnt/β-catenin signaling pathway cooperates with the Notch signaling pathway to maintain the function of the Lgr5-positive ISCs.
文摘微型仿生机器人是一种仿照生物外形和运动形态制作设计的机器人,凭借其体型小、机动性高、环境适应性强等优点,在复杂环境探索、敌情侦察等特殊场景中具有较高的应用前景,近年来备受研究人员的关注.但是微型机器人运动稳定性弱、单目相机环境感知精度低等问题的存在一直制约着其实际应用.本文仿照昆虫“独角仙”设计了一种新的微型仿生爬虫机器人,开发了基于生物运动调控机制的六足机器人控制系统,改进了基于啮齿类动物空间导航原理的同时定位与建图系统.使用自研的微型仿生爬虫机器人在人造沙盘和真实室内走廊两个场景中进行了实验验证.在人造沙盘场景,由于微型仿生爬虫机器人提供的环境图像质量模糊,ORB-SLAM3算法无法完成回环检测,不能正确识别曾经见过的场景.类脑同步定位与地图构建(simultaneous localization and mapping,SLAM)系统回环准确率高达100%,比原RatSLAM算法提高了4.36%.在真实室内走廊场景,ORB-SLAM3算法和RatSLAM算法建图效果都比较差,而类脑SLAM不仅有着较好的建图结果,而且在准确率100%的同时召回率也高达97.87%.与ORB-SLAM3和RatSLAM算法相比,类脑SLAM系统取得了较好的建图结果.因此,自研的微型仿生爬虫机器人具有灵活的运动能力、鲁棒的导航定位能力,促使微型仿生机器人离实际应用更近了一步.
基金Acknowledgments This work was supported by the National Nature Science Foundation of China （NSFC, No. 30400296）, Natural Science Foundation of Hebei Province, China （C2006000443, C2008000277, C2010000706）
文摘Xenorhabdus nematophila, a Gram-negative proteobacterium belonging to the family Enterobacteriaceae and associated symbiotically with soil entomopathogenic nematodes, Steinernema carpocapsae, is pathogenic to a wide range of insects. A protein complex with insecticidal activity was isolated from the cells ofX. nematophila HB310 strain using methods of salting out and native polyacrylamide gel electrophoresis （PAGE）. Seven polypeptides ranging 50~250 kDa were well separated from the protein complex （named Xnpt） by sodium dodecyl sulfate （SDS）-PAGE, five of which are identified as XptA2, xptC 1, XptB 1, GroEL and hypothetical protein by matrix-assisted laser desorption- time-of-flight mass spectrometry （MALDI-TOFMS）. Xnpt showed high oral virulence to larvae of diamondback moth （DBM）, Plutella xylostella L. （Lepidoptera, Plutellidae） as its median lethal concentration （LC50） against second and third instar larvae were 331.45 ng/mL and 553.59 ng/mL at 72 h, respectively. The histological analysis of Xnptfed DBM larvae showed extensive histopathological effects on the midgut. Biochemical analysis indicated that Xnpt markedly inhibited the activities of three important enzymes in the midgut. Overall, our data showed that the protein complex isolated from X. nematophila HB310 induced the antifeedant and death of insects by destroying midgut tissues and inhibiting midgut proteases activities.
