Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in ...Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate.展开更多
The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns:(i) between Eurasian and western North American deserts with the Mediterranean climate(the Madrean-Tethyan ...The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns:(i) between Eurasian and western North American deserts with the Mediterranean climate(the Madrean-Tethyan disjunctions);and(ii) between the temperate regions of North and South America(the amphitropical disjunctions).Both disjunct patterns have multiple times of origin.The amphitropical disjunctions have largely resulted from long-distance dispersal,primarily from the Miocene to the Holocene,with available data indicating that most lineages dispersed from North to South America.Results of recent studies on the Mediterranean disjuncts between the deserts of Eurasia and western North America support the multiple modes of origin and are mostly consistent with hypotheses of long-distance dispersal and the North Atlantic migration.Axelrod's Madrean-Tethyan hypothesis,which implies vicariance between the two regions in the early Tertiary,has been favored by a few studies.The Beringian migration corridor for semiarid taxa is also supported in some cases.展开更多
Toxicodendron is a genus in the Rhus complex of Anacardiaceae with a disjunct distribution between eastern Asia and North America,extending to southeastern Asia and the neotropics.Nuclear(internal transcribed spacer,e...Toxicodendron is a genus in the Rhus complex of Anacardiaceae with a disjunct distribution between eastern Asia and North America,extending to southeastern Asia and the neotropics.Nuclear(internal transcribed spacer,external transcribed spacer,and NIA-i3) and chloroplast(ndhF and trnL-F) sequences were used to construct phylogenetic relationships of Toxicodendron.Phylogenetic analysis of these data strongly support Toxicodendron as a monophyletic group distinct from other genera of the Rhus complex,and the phylogeny does not fully corroborate classification at the sectional level.Two temperate disjunct lineages were detected,one from section Toxicodendron and the other between the eastern North American Toxicodendron vernix and the eastern Asian Toxicodendron ver-nicifluum.Their divergence times were estimated to be 13.46(7.95-19.42) and 7.53(2.76-12.86) mya,respectively.The disjunction between section Griffithii(taxa from warm temperate to tropical Asia) and Toxicodendron striatum(from the neotropics) was supported and their divergence time was estimated to be 20.84(11.16-30.52) mya in the early Miocene.Our biogeographic results and the paleontological data support the Bering land bridge as the most likely route to explain the temperate disjunctions,yet the tropical disjunction in Toxicodendron seems to be best explained by the North Atlantic land bridge hypothesis.展开更多
The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long deb...The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long debated. Chamaecyparis is a good model to test previous hypotheses about the formation of this disjunct pattern as it contains six species disjunctly distributed in EA, western North America(WNA)and eastern North America(ENA). In this study, we applied ecological niche models to test the formation of the disjunct pattern of Chamaecyparis. The model calibrated with the EA species was able to predict the distribution of eastern NA species well, but not the western NA species. Furthermore, the eastern Asian species were shown to have higher niche overlap with the eastern North American species. The EA species were also shown to share more similar habitats with ENA species than with WNA species in the genus. Chamaecyparis species in WNA experienced a significant niche shift compared with congeneric species. Chamaecyparis had a low number of suitable regions in Europe and the middle and western NA during the Last Glacial Maximum(LGM) period, and became extinct in the former region whereas it retains residual distribution in the latter. The extirpations in western NA and Europe in response to the late Neogene and Quaternary climatic cooling and the more similar habitats between ENA and EA ultimately shaped the current intercontinental disjunct distribution of Chamaecyparis. Both current hypotheses may be also jointly applied to explain more eastern Asian and eastern North American disjunctions observed today.展开更多
In the central nervous system, the formation of fibrotic scar after injury inhibits axon regeneration and promotes repair. However, the mechanism underlying fibrotic scar formation and regulation remains poorly unders...In the central nervous system, the formation of fibrotic scar after injury inhibits axon regeneration and promotes repair. However, the mechanism underlying fibrotic scar formation and regulation remains poorly understood. M2 macrophages regulate fibrotic scar formation after injury to the heart, lung, kidney, and central nervous system. However, it remains to be clarified whether and how M2 macrophages regulate fibrotic scar formation after cerebral ischemia injury. In this study, we found that, in a rat model of cerebral ischemia induced by middle cerebral artery occlusion/reperfusion, fibrosis and macrophage infiltration were apparent in the ischemic core in the early stage of injury(within 14 days of injury). The number of infiltrated macrophages was positively correlated with fibronectin expression. Depletion of circulating monocyte-derived macrophages attenuated fibrotic scar formation. Interleukin 4(IL4) expression was strongly enhanced in the ischemic cerebral tissues, and IL4-induced M2 macrophage polarization promoted fibrotic scar formation in the ischemic core. In addition, macrophage-conditioned medium directly promoted fibroblast proliferation and the production of extracellular matrix proteins in vitro. Further pharmacological and genetic analyses showed that sonic hedgehog secreted by M2 macrophages promoted fibrogenesis in vitro and in vivo, and that this process was mediated by secretion of the key fibrosis-associated regulatory proteins transforming growth factor beta 1 and matrix metalloproteinase 9. Furthermore, IL4-afforded functional restoration on angiogenesis, cell apoptosis, and infarct volume in the ischemic core of cerebral ischemia rats were markedly impaired by treatment with an sonic hedgehog signaling inhibitor, paralleling the extent of fibrosis. Taken together, our findings show that IL4/sonic hedgehog/transforming growth factor beta 1 signaling targeting macrophages regulates the formation of fibrotic scar and is a potential therapeutic target for ischemic stroke.展开更多
Prunus is an economically important genus widely distributed in the temperate Northern Hemisphere.Previous studies on the genus using a variety of loci yielded conflicting phylogenetic hypotheses.Here,we generated nuc...Prunus is an economically important genus widely distributed in the temperate Northern Hemisphere.Previous studies on the genus using a variety of loci yielded conflicting phylogenetic hypotheses.Here,we generated nuclear reduced representation sequencing data and plastid genomes for 36 Prunus individuals and two outgroups.Both nuclear and plastome data recovered a well-resolved phylogeny.The species were divided into three main clades corresponding to their inflorescence types,-the racemose group,the solitary-flower group and the corymbose group-with the latter two sister to one another.Prunus was inferred to have diversified initially in the Late Cretaceous around 67.32 million years ago.The diversification of the three major clades began between the Paleocene and Miocene,suggesting that paleoclimatic events were an important driving force for Prunus diversification.Ancestral state reconstructions revealed that the most recent common ancestor of Prunus had racemose inflorescences,and the solitary-flower and corymb inflorescence types were derived by reduction of flower number and suppression of the rachis,respectively.We also tested the hybrid origin hypothesis of the racemose group proposed in previous studies.Prunus has undergone extensive hybridization events,although it is difficult to identify conclusively specific instances of hybridization when using SNP data,especially deep in the phylogeny.Our study provides well-resolved nuclear and plastid phylogenies of Prunus,reveals substantial cytonuclear discord at shallow scales,and sheds new light on inflorescence evolution in this economically important lineage.展开更多
Alpine wetland is one of the typical underlying surfaces on the Qinghai–Tibet Plateau.It plays a crucial role in runoff regulation.Investigations on the mechanisms of water and heat exchanges are necessary to underst...Alpine wetland is one of the typical underlying surfaces on the Qinghai–Tibet Plateau.It plays a crucial role in runoff regulation.Investigations on the mechanisms of water and heat exchanges are necessary to understand the land surface processes over the alpine wetland.This study explores the characteristics of hydro-meteorological factors with in situ observations and uses the Community Land Model 5 to identify the main factors controlling water and heat exchanges.Latent heat flux and thermal roughness length were found to be greater in the warm season(June–August)than in the cold season(December–February),with a frozen depth of 20–40 cm over the alpine wetland.The transfers of heat fluxes were mainly controlled by longwave radiation and air temperature and affected by root distribution.Air pressure and stomatal conductance were also important to latent heat flux,and soil solid water content was important to sensible heat flux.Soil temperature was dominated by longwave radiation and air temperature,with crucial surface parameters of initial soil liquid water content and total water content.The atmospheric control factors transitioned to precipitation and air temperature for soil moisture,especially at the shallow layer(5 cm).Meanwhile,the more influential surface parameters were root distribution and stomatal conductance in the warm season and initial soil liquid water content and total water content in the cold season.This work contributes to the research on the land surface processes over the alpine wetland and is helpful to wetland protection.展开更多
BACKGROUND Portal hypertension combined with esophagogastric variceal bleeding(EGVB)is a serious complication in patients with hepatitis B virus(HBV)-related cirrhosis in China.Splenectomy plus pericardial devasculari...BACKGROUND Portal hypertension combined with esophagogastric variceal bleeding(EGVB)is a serious complication in patients with hepatitis B virus(HBV)-related cirrhosis in China.Splenectomy plus pericardial devascularization(SPD)and transjugular intrahepatic portosystemic shunt(TIPS)are effective treatments for EGVB.However,a comparison of the effectiveness and safety of those methods is lacking.AIM To compare the prognosis after SPD vs TIPS for acute EGVB after failure of endoscopic therapy or secondary prophylaxis of variceal rebleeding(VRB)in patients with HBV-related cirrhosis combined with portal hypertension.METHODS This retrospective cohort study included 318 patients with HBV-related cirrhosis and EGVB who underwent SPD or TIPS at West China Hospital of Sichuan University during 2009-2013.Propensity score-matched analysis(PSM),the Kaplan-Meier method,and multivariate Cox regression analysis were used to compare overall survival,VRB rate,liver function abnormality rate,and hepatocellular carcinoma(HCC)incidence between the two patient groups.RESULTS The median age was 45.0 years(n=318;226(71.1%)males).During a median follow-up duration of 43.0 mo,18(11.1%)and 33(21.2%)patients died in the SPD and TIPS groups,respectively.After PSM,SPD was significantly associated with better overall survival(OS)(P=0.01),lower rates of abnormal liver function(P<0.001),and a lower incidence of HCC(P=0.02)than TIPS.The VRB rate did not differ significantly between the two groups(P=0.09).CONCLUSION Compared with TIPS,SPD is associated with higher postoperative OS rates,lower rates of abnormal liver function and HCC,and better quality of survival as acute EGVB treatment after failed endoscopic therapy or as secondary prophylaxis of VRB in patients with HBV-related cirrhosis combined with portal hypertension.There is no significant between-group difference in VRB rates.展开更多
Objective:This general non-systematic review aimed to gather information on reported statistical models examing the effects of meteorological factors on coronavirus disease 2019(COVID-19)and compare these models.Metho...Objective:This general non-systematic review aimed to gather information on reported statistical models examing the effects of meteorological factors on coronavirus disease 2019(COVID-19)and compare these models.Methods:PubMed,Web of Science,and Google Scholar were searched for studies on"meteorological factors and COVID-19"published between January 1,2020,and October 1,2022.Results:The most commonly used approaches for analyzing the association between meteorological factors and COVID-19 were the linear regression model(LRM),generalized linear model(GLM),generalized additive model(GAM),and distributed lag non-linear model(DLNM).In addition to these classical models commonly applied in environmental epidemiology,machine learning techniques are increasingly being used to select risk factors for the outcome of interest and establishing robust prediction models.Conclusion:Selecting an appropriate model is essential before conducting research.To ensure the reliability of analysis results,it is important to consider including non-meteorological factors(e.g.,government policies on physical distancing,vaccination,and hygiene practices)along with meteorological factors in the model.展开更多
Teaching reform is an important work indispensable for the long-term development of the open university,and it is also the development trend of the advertising art design major in open education to keep up with the ne...Teaching reform is an important work indispensable for the long-term development of the open university,and it is also the development trend of the advertising art design major in open education to keep up with the new media era.Based on the current situation of advertising art design major in open education,this paper analyzes the necessity of implementing the online and offline mixed teaching reform in this major,and puts forward the specific teaching reform measures in three aspects.展开更多
Background: Precut sphincterotomy has been widely performed to facilitate selective biliary access when standard cannulation attempts failed during endoscopic retrograde cholangiopancreatography(ERCP). However, scarce...Background: Precut sphincterotomy has been widely performed to facilitate selective biliary access when standard cannulation attempts failed during endoscopic retrograde cholangiopancreatography(ERCP). However, scarce data are available on different precut techniques for difficult biliary cannulation. This study aimed to evaluate the efficacy and safety of transpancreatic septotomy(TPS), needle-knife fistulotomy(NKF) or both based on the presence of unintentional pancreatic access and papillary morphology. Methods: Between March 2008 and December 2016, 157 consecutive patients undergoing precutting for an inaccessible bile duct during ERCP were identified. Precut techniques were chosen depending on repetitive inadvertent pancreatic cannulation and the papillary morphology. We retrospectively assessed the rates of cannulation success and procedure-related complications among three groups, namely TPS, NKF, and TPS followed by NKF. Results: The baseline characteristics of the three groups were comparable. The overall success rate of biliary cannulation reached 98.1%, including 111 of 113(98.2%) with TPS, 35 of 36(97.2%) with NKF and 8 of 8(100%) with NKF following TPS, without significant difference among groups. The incidences of total complications and post-ERCP pancreatitis were 9.6% and 7.6%, respectively. There was a trend towards less frequent post-ERCP pancreatitis after NKF(0%) compared with 11 cases(9.7%) after TPS and one case(12.5%) after NKF following TPS, but not significantly different( P = 0.07). No severe adverse event occurred during this study period. Conclusions: The choice of precut techniques by the presence of unintended pancreatic access and the papillary morphology brought about a high success rate without increasing risk in difficult biliary cannulation.展开更多
Scientists and the local government have great concerns about the climate change and water resources in the Badain Jaran Desert of western China. A field study for the local water cycle of a lake-desert system was con...Scientists and the local government have great concerns about the climate change and water resources in the Badain Jaran Desert of western China. A field study for the local water cycle of a lake-desert system was conducted near the Noertu Lake in the Badain Jaran Desert from 21 June to 26 August 2008. An underground wet sand layer was observed at a depth of 20–50 cm through analysis of datasets collected during the field experiment. Measurements unveiled that the near surface air humidity increased in the nighttime. The sensible and latent heat fluxes were equivalent at a site about 50 m away from the Noertu Lake during the daytime, with mean values of 134.4 and 105.9 W/m2 respectively. The sensible heat flux was dominant at a site about 500 m away from the Noertu Lake, with a mean of 187.7 W/m2, and a mean latent heat flux of only 26.7 W/m2. There were no apparent differences for the land surface energy budget at the two sites during the night time. The latent heat flux was always negative with a mean value of –12.7 W/m2, and the sensible heat flux was either positive or negative with a mean value of 5.10 W/m2. A portion of the local precipitation was evaporated into the air and the top-layer of sand dried quickly after every rainfall event, while another portion seeped deep and was trapped by the underground wet sand layer, and supplied water for surface psammophyte growth. With an increase of air humidity and the occurrence of negative latent heat flux or water vapor condensation around the Noertu Lake during the nighttime, we postulated that the vapor was transported and condensed at the lakeward sand surface, and provided supplemental underground sand pore water. There were links between the local water cycle, underground wet sand layer, psammophyte growth and landscape evolution of the mega-dunes surrounding the lakes in the Badain Jaran Desert of western China.展开更多
Background: Endoscopic papillary balloon dilation(EPBD) for common bile duct(CBD) stones removal in Billroth Ⅱ gastrectomy patients is feasible. However, the long-term outcomes of this technique are not clear. The ai...Background: Endoscopic papillary balloon dilation(EPBD) for common bile duct(CBD) stones removal in Billroth Ⅱ gastrectomy patients is feasible. However, the long-term outcomes of this technique are not clear. The aim of this study was to evaluate the procedural and long-term outcomes of EPBD for removal of CBD stones in Billroth Ⅱ gastrectomy patients.Methods: The records of patients with previous Billroth Ⅱ gastrectomy referred for CBD stones removal with endoscopic retrograde cholangiopancreatography(ERCP) between July 1, 2008 and September 1,2016 were retrospectively reviewed. The main outcomes of stone clearance, ERCP-related adverse events,and stone recurrence were analyzed.Results: A total of 83 patients with previous Billroth Ⅱ gastrectomy underwent ERCP in our center were reviewed. Forty-nine consecutive patients with previous Billroth Ⅱ gastrectomy referred to EPBD for removal of CBD stones underwent 59 ERCP procedures were enrolled in the end. The overall successful CBD stones clearance was achieved in 42 patients(85.7%). ERCP-related adverse events was in 3 ERCP procedures(5.1%). Severe complications, including perforation and bleeding, were not observed. Six of 49 patients(12.2%) had stone recurrence after a median period of22.5 months(range 6–71 months) from the end of stone removal treatment. Female [odds ratio(OR) = 11.352; 95% confidence interval(95% CI): 1.040–123.912; P = 0.046] and previous mechanical lithotripsy(OR = 13.423; 95% CI: 1.070–168.434; P = 0.044) were significantly associated with stone recurrence.Conclusions: At long-term follow-up, EPBD for removal of CBD stones appeared to be safe and effective in Billroth Ⅱ gastrectomy patients. Female and previous mechanical lithotripsy may be risk factors for stone recurrence.展开更多
Sequences of the chloroplast ndhF gene and the nuclear ribosomal ITS regions are employed to recon-struct the phylogeny of Prunus (Rosaceae), and evaluate the classification schemes of this genus. The two data sets ar...Sequences of the chloroplast ndhF gene and the nuclear ribosomal ITS regions are employed to recon-struct the phylogeny of Prunus (Rosaceae), and evaluate the classification schemes of this genus. The two data sets are congruent in that the genera Prunus s.l. and Maddenia form a monophyletic group, with Maddenia nested within Prunus. However, the ndhF data set is incongruent with the ITS data supporting two major groups within Prunus: one consisting of subgenera Laurocerasus (including Pygeum) and Padus as well as the genus Maddenia and another of subgenera Amygdalus, Cerasus, and Prunus. The ITS data, on the other hand, support a clade composed of subgenera Amygdalus and Prunus and Prunus sect. Microcerasus in addition to a paraphyletic grade of subgenera Laurocerasus and Padus (and the genus Maddenia) taxa. In general, the subgeneric classifications of Prunus s.l. are not supported. The ITS and ndhF phylogenies differ mainly in interspecific relationships and the relative position of the Padus/Laurocerasus group. Both ITS and ndhF data sets suggest that the formerly recog-nized genus Pygeum is polyphyletic and that the distinction of the subgenera Padus and Laurocerasus is not supported. The biogeographic interactions of the temperate and tropical members in the Padus/Laurocera- sus/Maddenia alliance including Pygeum are shown to be highly dynamic and complex.展开更多
Only two cases of myofibroblastic sarcoma in the liver have been reported in the literature. Here, we report the case of a male patient with high-grade myofibroblastic sarcoma mimicking echinococcosis in the liver. Th...Only two cases of myofibroblastic sarcoma in the liver have been reported in the literature. Here, we report the case of a male patient with high-grade myofibroblastic sarcoma mimicking echinococcosis in the liver. The 25-year-old male patient complained of right upper quadrant swelling pain for one week and was initially diagnosed with echinococcosis. He was then scheduled for an exploratory laparotomy. During the operation, a huge mass exceeding 16 cm in diameter was found to occupy nearly the entire right trisegment of the liver, with a clear boundary and a round shape, and the mass was resected by right hepatic trisegmentectomy. Immunohistochemical staining revealed that the tumor tissue was positive for desmin, α-smooth muscle actin, CD56, and vimentin and negative for ALK-1, myogenin, calponin, β-catenin, S100, and glypican-3, with a Ki-67(MIB-1) index of approximately 20%. Based on the histological manifestations and immunohistochemical staining, a diagnosis of myofibroblastic sarcoma was established. The postoperative recovery was uneventful. There was no evidence of recurrence or metastasis through the last follow-up, 6 mo after surgery, despite a lack of postoperative chemotherapy or radiotherapy. To the best of our knowledge, the present case is the first reported case of high-grade myofibroblastic sarcoma in the liver, and it is also the first reported case in a male patient.展开更多
基金the National Natural Science Foundation of China(Grant Nos.42205059 and 42005075)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant Nos.XDA23090303 and XDB40010302)+1 种基金the State Key Laboratory of Cryospheric Science(Grant No.SKLCS-ZZ-2024 and SKLCS-ZZ-2023)the Key Laboratory of Mountain Hazards and Earth Surface Processes.
文摘Little is known about the mechanism of climate-vegetation coverage coupled changes in the Tibetan Plateau(TP)region,which is the most climatically sensitive and ecologically fragile region with the highest terrain in the world.This study,using multisource datasets(including satellite data and meteorological observations and reanalysis data)revealed the mutual feedback mechanisms between changes in climate(temperature and precipitation)and vegetation coverage in recent decades in the Hengduan Mountains Area(HMA)of the southeastern TP and their influences on climate in the downstream region,the Sichuan Basin(SCB).There is mutual facilitation between rising air temperature and increasing vegetation coverage in the HMA,which is most significant during winter,and then during spring,but insignificant during summer and autumn.Rising temperature significantly enhances local vegetation coverage,and vegetation greening in turn heats the atmosphere via enhancing net heat flux from the surface to the atmosphere.The atmospheric heating anomaly over the HMA thickens the atmospheric column and increases upper air pressure.The high pressure anomaly disperses downstream via the westerly flow,expands across the SCB,and eventually increases the SCB temperature.This effect lasts from winter to the following spring,which may cause the maximum increasing trend of the SCB temperature and vegetation coverage in spring.These results are helpful for estimating future trends in climate and eco-environmental variations in the HMA and SCB under warming scenarios,as well as seasonal forecasting based on the connection between the HMA eco-environment and SCB climate.
基金supported,in part,by grants from the National Science Foundation (DEB 045573 to Michael DILLON and Jun WENand DEB 0743474 to Steve MANCHESTER and Jun WEN)support for S. ICKERT-BOND from the National Museum of Natural History,the Smithsonian Institution
文摘The present paper reviews advances in the study of two major intercontinental disjunct biogeographic patterns:(i) between Eurasian and western North American deserts with the Mediterranean climate(the Madrean-Tethyan disjunctions);and(ii) between the temperate regions of North and South America(the amphitropical disjunctions).Both disjunct patterns have multiple times of origin.The amphitropical disjunctions have largely resulted from long-distance dispersal,primarily from the Miocene to the Holocene,with available data indicating that most lineages dispersed from North to South America.Results of recent studies on the Mediterranean disjuncts between the deserts of Eurasia and western North America support the multiple modes of origin and are mostly consistent with hypotheses of long-distance dispersal and the North Atlantic migration.Axelrod's Madrean-Tethyan hypothesis,which implies vicariance between the two regions in the early Tertiary,has been favored by a few studies.The Beringian migration corridor for semiarid taxa is also supported in some cases.
基金supported bygrants from the National Basic Research Program of China (973 Program,grant no. 2007CB411601)the National Natural Science Foundation of China (grant nos.30625004 and 40771073 to H. Sun)+2 种基金the Yunnan Natural Science Foundation (grant no. 2008CC013)the John D. and Catherine T. MacArthur Foundation (to J.Wen)supported by the Laboratory of Analytical Biology of the National Museum of Natural History,Smithsonian Institution,Washington DC,USA
文摘Toxicodendron is a genus in the Rhus complex of Anacardiaceae with a disjunct distribution between eastern Asia and North America,extending to southeastern Asia and the neotropics.Nuclear(internal transcribed spacer,external transcribed spacer,and NIA-i3) and chloroplast(ndhF and trnL-F) sequences were used to construct phylogenetic relationships of Toxicodendron.Phylogenetic analysis of these data strongly support Toxicodendron as a monophyletic group distinct from other genera of the Rhus complex,and the phylogeny does not fully corroborate classification at the sectional level.Two temperate disjunct lineages were detected,one from section Toxicodendron and the other between the eastern North American Toxicodendron vernix and the eastern Asian Toxicodendron ver-nicifluum.Their divergence times were estimated to be 13.46(7.95-19.42) and 7.53(2.76-12.86) mya,respectively.The disjunction between section Griffithii(taxa from warm temperate to tropical Asia) and Toxicodendron striatum(from the neotropics) was supported and their divergence time was estimated to be 20.84(11.16-30.52) mya in the early Miocene.Our biogeographic results and the paleontological data support the Bering land bridge as the most likely route to explain the temperate disjunctions,yet the tropical disjunction in Toxicodendron seems to be best explained by the North Atlantic land bridge hypothesis.
基金funded by grants from the Ministry of Science and Technology of China, Basic Research Project(No. 2013FY112600)the Talent Project of Yunnan Province(No. 2011CI042)
文摘The disjunct distribution of plants between eastern Asia(EA) and North America(NA) is one of the most well-known biogeographic patterns. However, the formation and historical process of this pattern have been long debated. Chamaecyparis is a good model to test previous hypotheses about the formation of this disjunct pattern as it contains six species disjunctly distributed in EA, western North America(WNA)and eastern North America(ENA). In this study, we applied ecological niche models to test the formation of the disjunct pattern of Chamaecyparis. The model calibrated with the EA species was able to predict the distribution of eastern NA species well, but not the western NA species. Furthermore, the eastern Asian species were shown to have higher niche overlap with the eastern North American species. The EA species were also shown to share more similar habitats with ENA species than with WNA species in the genus. Chamaecyparis species in WNA experienced a significant niche shift compared with congeneric species. Chamaecyparis had a low number of suitable regions in Europe and the middle and western NA during the Last Glacial Maximum(LGM) period, and became extinct in the former region whereas it retains residual distribution in the latter. The extirpations in western NA and Europe in response to the late Neogene and Quaternary climatic cooling and the more similar habitats between ENA and EA ultimately shaped the current intercontinental disjunct distribution of Chamaecyparis. Both current hypotheses may be also jointly applied to explain more eastern Asian and eastern North American disjunctions observed today.
基金supported by the National Natural Science Foundation of China,Nos.82171456 (to QY),81971229 (to QY)the Natural Science Foundation of Chongqing,No.cstc2021jcyj-msxmX0263 (to QY)the Postgraduate Research and Innovation Project of Chongqing,Nos.CYB20151 (to QY),CYS19182 (to YC)。
文摘In the central nervous system, the formation of fibrotic scar after injury inhibits axon regeneration and promotes repair. However, the mechanism underlying fibrotic scar formation and regulation remains poorly understood. M2 macrophages regulate fibrotic scar formation after injury to the heart, lung, kidney, and central nervous system. However, it remains to be clarified whether and how M2 macrophages regulate fibrotic scar formation after cerebral ischemia injury. In this study, we found that, in a rat model of cerebral ischemia induced by middle cerebral artery occlusion/reperfusion, fibrosis and macrophage infiltration were apparent in the ischemic core in the early stage of injury(within 14 days of injury). The number of infiltrated macrophages was positively correlated with fibronectin expression. Depletion of circulating monocyte-derived macrophages attenuated fibrotic scar formation. Interleukin 4(IL4) expression was strongly enhanced in the ischemic cerebral tissues, and IL4-induced M2 macrophage polarization promoted fibrotic scar formation in the ischemic core. In addition, macrophage-conditioned medium directly promoted fibroblast proliferation and the production of extracellular matrix proteins in vitro. Further pharmacological and genetic analyses showed that sonic hedgehog secreted by M2 macrophages promoted fibrogenesis in vitro and in vivo, and that this process was mediated by secretion of the key fibrosis-associated regulatory proteins transforming growth factor beta 1 and matrix metalloproteinase 9. Furthermore, IL4-afforded functional restoration on angiogenesis, cell apoptosis, and infarct volume in the ischemic core of cerebral ischemia rats were markedly impaired by treatment with an sonic hedgehog signaling inhibitor, paralleling the extent of fibrosis. Taken together, our findings show that IL4/sonic hedgehog/transforming growth factor beta 1 signaling targeting macrophages regulates the formation of fibrotic scar and is a potential therapeutic target for ischemic stroke.
基金This work was supported by grants from National Natural Science Foundation of China(No.32170381 and 31770200).
文摘Prunus is an economically important genus widely distributed in the temperate Northern Hemisphere.Previous studies on the genus using a variety of loci yielded conflicting phylogenetic hypotheses.Here,we generated nuclear reduced representation sequencing data and plastid genomes for 36 Prunus individuals and two outgroups.Both nuclear and plastome data recovered a well-resolved phylogeny.The species were divided into three main clades corresponding to their inflorescence types,-the racemose group,the solitary-flower group and the corymbose group-with the latter two sister to one another.Prunus was inferred to have diversified initially in the Late Cretaceous around 67.32 million years ago.The diversification of the three major clades began between the Paleocene and Miocene,suggesting that paleoclimatic events were an important driving force for Prunus diversification.Ancestral state reconstructions revealed that the most recent common ancestor of Prunus had racemose inflorescences,and the solitary-flower and corymb inflorescence types were derived by reduction of flower number and suppression of the rachis,respectively.We also tested the hybrid origin hypothesis of the racemose group proposed in previous studies.Prunus has undergone extensive hybridization events,although it is difficult to identify conclusively specific instances of hybridization when using SNP data,especially deep in the phylogeny.Our study provides well-resolved nuclear and plastid phylogenies of Prunus,reveals substantial cytonuclear discord at shallow scales,and sheds new light on inflorescence evolution in this economically important lineage.
基金supported by the National Natural Science Foundation of China(Grant Nos.42005075,41975130)Natural Science Foundation of Gansu Province(Grant No.21JR7RA047)+1 种基金Open Research Fund Program of Plateau Atmosphere and Environment Key Laboratory of Sichuan Province(Grant No.PAEKL-2022-K03)the State Key Laboratory of Cryospheric Science(Grant No.SKLCS-ZZ-2023,SKLCS-ZZ-2022).
文摘Alpine wetland is one of the typical underlying surfaces on the Qinghai–Tibet Plateau.It plays a crucial role in runoff regulation.Investigations on the mechanisms of water and heat exchanges are necessary to understand the land surface processes over the alpine wetland.This study explores the characteristics of hydro-meteorological factors with in situ observations and uses the Community Land Model 5 to identify the main factors controlling water and heat exchanges.Latent heat flux and thermal roughness length were found to be greater in the warm season(June–August)than in the cold season(December–February),with a frozen depth of 20–40 cm over the alpine wetland.The transfers of heat fluxes were mainly controlled by longwave radiation and air temperature and affected by root distribution.Air pressure and stomatal conductance were also important to latent heat flux,and soil solid water content was important to sensible heat flux.Soil temperature was dominated by longwave radiation and air temperature,with crucial surface parameters of initial soil liquid water content and total water content.The atmospheric control factors transitioned to precipitation and air temperature for soil moisture,especially at the shallow layer(5 cm).Meanwhile,the more influential surface parameters were root distribution and stomatal conductance in the warm season and initial soil liquid water content and total water content in the cold season.This work contributes to the research on the land surface processes over the alpine wetland and is helpful to wetland protection.
基金the National Key R&D Program of China,No.2022YFC2503701the Science and Technological Supports Project of Sichuan Province,No.2022YFS0255the National Natural Science Foundation of China,No.81800449.
文摘BACKGROUND Portal hypertension combined with esophagogastric variceal bleeding(EGVB)is a serious complication in patients with hepatitis B virus(HBV)-related cirrhosis in China.Splenectomy plus pericardial devascularization(SPD)and transjugular intrahepatic portosystemic shunt(TIPS)are effective treatments for EGVB.However,a comparison of the effectiveness and safety of those methods is lacking.AIM To compare the prognosis after SPD vs TIPS for acute EGVB after failure of endoscopic therapy or secondary prophylaxis of variceal rebleeding(VRB)in patients with HBV-related cirrhosis combined with portal hypertension.METHODS This retrospective cohort study included 318 patients with HBV-related cirrhosis and EGVB who underwent SPD or TIPS at West China Hospital of Sichuan University during 2009-2013.Propensity score-matched analysis(PSM),the Kaplan-Meier method,and multivariate Cox regression analysis were used to compare overall survival,VRB rate,liver function abnormality rate,and hepatocellular carcinoma(HCC)incidence between the two patient groups.RESULTS The median age was 45.0 years(n=318;226(71.1%)males).During a median follow-up duration of 43.0 mo,18(11.1%)and 33(21.2%)patients died in the SPD and TIPS groups,respectively.After PSM,SPD was significantly associated with better overall survival(OS)(P=0.01),lower rates of abnormal liver function(P<0.001),and a lower incidence of HCC(P=0.02)than TIPS.The VRB rate did not differ significantly between the two groups(P=0.09).CONCLUSION Compared with TIPS,SPD is associated with higher postoperative OS rates,lower rates of abnormal liver function and HCC,and better quality of survival as acute EGVB treatment after failed endoscopic therapy or as secondary prophylaxis of VRB in patients with HBV-related cirrhosis combined with portal hypertension.There is no significant between-group difference in VRB rates.
基金funded by the National Natural Science Foundation of China(8177120753)the China-Australia International Collaborative Grant(NHMRC APP1112767,NSFC 81561128020)Zheng Y L and Guo Z were supported by the Edith Cowan University Higher Degree by Research Scholarship(ECU-HDR ST10469322 and ST10468211).
文摘Objective:This general non-systematic review aimed to gather information on reported statistical models examing the effects of meteorological factors on coronavirus disease 2019(COVID-19)and compare these models.Methods:PubMed,Web of Science,and Google Scholar were searched for studies on"meteorological factors and COVID-19"published between January 1,2020,and October 1,2022.Results:The most commonly used approaches for analyzing the association between meteorological factors and COVID-19 were the linear regression model(LRM),generalized linear model(GLM),generalized additive model(GAM),and distributed lag non-linear model(DLNM).In addition to these classical models commonly applied in environmental epidemiology,machine learning techniques are increasingly being used to select risk factors for the outcome of interest and establishing robust prediction models.Conclusion:Selecting an appropriate model is essential before conducting research.To ensure the reliability of analysis results,it is important to consider including non-meteorological factors(e.g.,government policies on physical distancing,vaccination,and hygiene practices)along with meteorological factors in the model.
基金Ningbo Open University 2023 university-level teaching reform project“Exploration and Practice of Online and Offline Mixed Teaching Reform in Advertising Art Design Major”(Project number:JG23-005)。
文摘Teaching reform is an important work indispensable for the long-term development of the open university,and it is also the development trend of the advertising art design major in open education to keep up with the new media era.Based on the current situation of advertising art design major in open education,this paper analyzes the necessity of implementing the online and offline mixed teaching reform in this major,and puts forward the specific teaching reform measures in three aspects.
文摘Background: Precut sphincterotomy has been widely performed to facilitate selective biliary access when standard cannulation attempts failed during endoscopic retrograde cholangiopancreatography(ERCP). However, scarce data are available on different precut techniques for difficult biliary cannulation. This study aimed to evaluate the efficacy and safety of transpancreatic septotomy(TPS), needle-knife fistulotomy(NKF) or both based on the presence of unintentional pancreatic access and papillary morphology. Methods: Between March 2008 and December 2016, 157 consecutive patients undergoing precutting for an inaccessible bile duct during ERCP were identified. Precut techniques were chosen depending on repetitive inadvertent pancreatic cannulation and the papillary morphology. We retrospectively assessed the rates of cannulation success and procedure-related complications among three groups, namely TPS, NKF, and TPS followed by NKF. Results: The baseline characteristics of the three groups were comparable. The overall success rate of biliary cannulation reached 98.1%, including 111 of 113(98.2%) with TPS, 35 of 36(97.2%) with NKF and 8 of 8(100%) with NKF following TPS, without significant difference among groups. The incidences of total complications and post-ERCP pancreatitis were 9.6% and 7.6%, respectively. There was a trend towards less frequent post-ERCP pancreatitis after NKF(0%) compared with 11 cases(9.7%) after TPS and one case(12.5%) after NKF following TPS, but not significantly different( P = 0.07). No severe adverse event occurred during this study period. Conclusions: The choice of precut techniques by the presence of unintended pancreatic access and the papillary morphology brought about a high success rate without increasing risk in difficult biliary cannulation.
基金supported by the European FP7 Programme: CORE-CLIMAX (313085)the National Natural Science Foundation of China (41175027)+1 种基金the Key Research Program of the Chinese Academy of Sciences (KZZD-EW-13)Chinese Academy of Sciences Fellowship for Young International Scientists (2012Y1ZA0013)
文摘Scientists and the local government have great concerns about the climate change and water resources in the Badain Jaran Desert of western China. A field study for the local water cycle of a lake-desert system was conducted near the Noertu Lake in the Badain Jaran Desert from 21 June to 26 August 2008. An underground wet sand layer was observed at a depth of 20–50 cm through analysis of datasets collected during the field experiment. Measurements unveiled that the near surface air humidity increased in the nighttime. The sensible and latent heat fluxes were equivalent at a site about 50 m away from the Noertu Lake during the daytime, with mean values of 134.4 and 105.9 W/m2 respectively. The sensible heat flux was dominant at a site about 500 m away from the Noertu Lake, with a mean of 187.7 W/m2, and a mean latent heat flux of only 26.7 W/m2. There were no apparent differences for the land surface energy budget at the two sites during the night time. The latent heat flux was always negative with a mean value of –12.7 W/m2, and the sensible heat flux was either positive or negative with a mean value of 5.10 W/m2. A portion of the local precipitation was evaporated into the air and the top-layer of sand dried quickly after every rainfall event, while another portion seeped deep and was trapped by the underground wet sand layer, and supplied water for surface psammophyte growth. With an increase of air humidity and the occurrence of negative latent heat flux or water vapor condensation around the Noertu Lake during the nighttime, we postulated that the vapor was transported and condensed at the lakeward sand surface, and provided supplemental underground sand pore water. There were links between the local water cycle, underground wet sand layer, psammophyte growth and landscape evolution of the mega-dunes surrounding the lakes in the Badain Jaran Desert of western China.
文摘Background: Endoscopic papillary balloon dilation(EPBD) for common bile duct(CBD) stones removal in Billroth Ⅱ gastrectomy patients is feasible. However, the long-term outcomes of this technique are not clear. The aim of this study was to evaluate the procedural and long-term outcomes of EPBD for removal of CBD stones in Billroth Ⅱ gastrectomy patients.Methods: The records of patients with previous Billroth Ⅱ gastrectomy referred for CBD stones removal with endoscopic retrograde cholangiopancreatography(ERCP) between July 1, 2008 and September 1,2016 were retrospectively reviewed. The main outcomes of stone clearance, ERCP-related adverse events,and stone recurrence were analyzed.Results: A total of 83 patients with previous Billroth Ⅱ gastrectomy underwent ERCP in our center were reviewed. Forty-nine consecutive patients with previous Billroth Ⅱ gastrectomy referred to EPBD for removal of CBD stones underwent 59 ERCP procedures were enrolled in the end. The overall successful CBD stones clearance was achieved in 42 patients(85.7%). ERCP-related adverse events was in 3 ERCP procedures(5.1%). Severe complications, including perforation and bleeding, were not observed. Six of 49 patients(12.2%) had stone recurrence after a median period of22.5 months(range 6–71 months) from the end of stone removal treatment. Female [odds ratio(OR) = 11.352; 95% confidence interval(95% CI): 1.040–123.912; P = 0.046] and previous mechanical lithotripsy(OR = 13.423; 95% CI: 1.070–168.434; P = 0.044) were significantly associated with stone recurrence.Conclusions: At long-term follow-up, EPBD for removal of CBD stones appeared to be safe and effective in Billroth Ⅱ gastrectomy patients. Female and previous mechanical lithotripsy may be risk factors for stone recurrence.
文摘Sequences of the chloroplast ndhF gene and the nuclear ribosomal ITS regions are employed to recon-struct the phylogeny of Prunus (Rosaceae), and evaluate the classification schemes of this genus. The two data sets are congruent in that the genera Prunus s.l. and Maddenia form a monophyletic group, with Maddenia nested within Prunus. However, the ndhF data set is incongruent with the ITS data supporting two major groups within Prunus: one consisting of subgenera Laurocerasus (including Pygeum) and Padus as well as the genus Maddenia and another of subgenera Amygdalus, Cerasus, and Prunus. The ITS data, on the other hand, support a clade composed of subgenera Amygdalus and Prunus and Prunus sect. Microcerasus in addition to a paraphyletic grade of subgenera Laurocerasus and Padus (and the genus Maddenia) taxa. In general, the subgeneric classifications of Prunus s.l. are not supported. The ITS and ndhF phylogenies differ mainly in interspecific relationships and the relative position of the Padus/Laurocerasus group. Both ITS and ndhF data sets suggest that the formerly recog-nized genus Pygeum is polyphyletic and that the distinction of the subgenera Padus and Laurocerasus is not supported. The biogeographic interactions of the temperate and tropical members in the Padus/Laurocera- sus/Maddenia alliance including Pygeum are shown to be highly dynamic and complex.
文摘Only two cases of myofibroblastic sarcoma in the liver have been reported in the literature. Here, we report the case of a male patient with high-grade myofibroblastic sarcoma mimicking echinococcosis in the liver. The 25-year-old male patient complained of right upper quadrant swelling pain for one week and was initially diagnosed with echinococcosis. He was then scheduled for an exploratory laparotomy. During the operation, a huge mass exceeding 16 cm in diameter was found to occupy nearly the entire right trisegment of the liver, with a clear boundary and a round shape, and the mass was resected by right hepatic trisegmentectomy. Immunohistochemical staining revealed that the tumor tissue was positive for desmin, α-smooth muscle actin, CD56, and vimentin and negative for ALK-1, myogenin, calponin, β-catenin, S100, and glypican-3, with a Ki-67(MIB-1) index of approximately 20%. Based on the histological manifestations and immunohistochemical staining, a diagnosis of myofibroblastic sarcoma was established. The postoperative recovery was uneventful. There was no evidence of recurrence or metastasis through the last follow-up, 6 mo after surgery, despite a lack of postoperative chemotherapy or radiotherapy. To the best of our knowledge, the present case is the first reported case of high-grade myofibroblastic sarcoma in the liver, and it is also the first reported case in a male patient.
