Ecological Networks of Allometric Growth,Feeding Behavior and Gut Microbiota in Chinese Alligator Hatchlings

Chinese alligator hatchlings in captivity are fragile and have a high mortality rate within first year.The body mass gain of reptile animals is closely related to their feeding behavior and gut microbiota.This study analyzed the intrinsic factors influencing the allometric growth of Chinese alligator hatchlings based on their body mass gain,feeding behavior,and gut microbiota.This information would enhance the health management of Chinese alligator hatchlings.There was a significant correlation between the total distance moved,the average number of conspecifics nearby,and body mass gain.Chinese alligator hatchlings with a greater growth rate showed greater activity and more independent behavior during feeding than those with a lower growth rate.Moreover,after feeding started,some functions of the gut microbiota showed significant relationships with growth rate and feeding activity.Chinese alligator hatchlings with a greater growth rate showed greater levels of heme biosynthesis than those with a lower growth rate,and feeding activity was inhibited by long-chain fatty acid biosynthesis.These results elucidate the relationships between health,feeding behavior,and the gut microbiota of Chinese alligator hatchlings.Understanding the intrinsic factors of their health and feeding behavior can improve the health management of Chinese alligator hatchlings in captivity for conservation.

Habitat Suitability and Distribution Pattern Response to Global Climate Change in a Widespread Species,the Asiatic Toad(Bufo gargarizans)

The distribution and diversity of the species are closely related to the global climate.As the most widely distributed species of Bufonidae in China,the study of the distribution pattern and habitat suitability of the Asiatic toad under climate change can help us understand the reply pattern of Bufonidae habitat to climate change.Here,combined with the Maxent model and GIS technology,the effects of climate change on the distribution pattern and habitat suitability of the Asiatic toad were comprehensively analyzed.The results show that the rainfall during the wettest season(Bio16)and the mean temperature of the driest season(Bio9)have a considerable impact on the distribution of the Asiatic toad.In the next 30 to 50 years,across the overall spacial scale of the Chinese mainland,the habitat of the Asiatic toad will be primarily in the eastern part of China and less in south part,while its distribution area will expand to the midwest and northwest parts of China.Overall,the area in which it can be distributed will be reduced and suitable habitat will shift to some regions of higher latitude and elevation.In a word,we systematically analyzed the changes of the distribution pattern and habitat suitability of the Asiatic toad with climate change,and we aim to provide data on how climatic variation may impact amphibians.

Host Genetic Background Impacts Microbiome Composition in Newborn Alligator

Genetic factors play a key role in determination of the structure of the cloacal flora for newborn Chinese Alligators.We collected the cloacal microbiomes for 24 newborn Chinese Alligators from three different genetic backgrounds for 16S gene amplicon sequencing.The number of cloacal flora for the Chinese Alligators from different groups was comparable but differed structurally.There were variations in proportions of floral compositions at the phylum and family levels;however,the main difference was at the genus level.There were two significant differences in richness and evenness among the three groups.Non-metric multidimensional scaling NMDS analysis revealed that the 24 samples could be clearly divided into three categories based on their genetic backgrounds(stress=0.0244).Thus,we postulated that newborn Chinese Alligators with different genetic backgrounds have different immune strengths,which affects individual responses to environmental microorganisms.In summary,newborn Chinese Alligators from different genetic backgrounds exhibit variations in cloacal microbiome.

Evaluation of miR-122-regulated suicide gene therapy for hepatocellular carcinoma in an orthotopic mouse model

Objective： Intratumoral administration of adenoviral vector encoding herpes simplex virus （HSV） thymidine kinase （TK） gene （Ad-TK） followed by systemic ganciclovir （GCV） is an effective approach in treating experimental hepatocellular carcinoma （HCC）. However, hepatotoxicity due to unwanted vector spread and suicide gene expression limited the application of this therapy, miR-122 is an abundant, liver-specific microRNA whose expression is decreased in human primary HCC and HCC-derived cell lines. These different expression profiles provide an opportunity to induce tumor-specific gene expression by miR-122 regulation. Methods： By inserting miR-122 target sequences （miR-122T） in the 3＇ untranslated region （UTR） ofTK gene, we constructed adenovirus （Ad） vectors expressing miR-122-regulated TK （Ad-TK-122T） and report genes. After intratumoral administration of Ad vectors into an orthotopic miR-122-deficient HCC mouse model, we observed the miR-122-regulated transgene expression and assessed the antitumor activity and safety of Ad-TK-122T. Results： Insertion of miR-122T specifically down-regulated transgene expression in vitro and selectively protected the miR-122-positive cells from killing by TK/GCV treatment. Insertion of miR-122T led to significant reduction of tansgene expression in the liver without inhibition of its expression in tumors in vivo, resulting in an 11-fold improvement of tumor-specific transgene expression. Intratumoral injection of Ad vectors mediated TK/GCV system led to a vector dosage-dependent regression of tumor. The insertion of miR-122T does not influence the antitumor effects of suicide gene therapy. Whereas mice administrated with Ad-TK showed severe lethal hepatotoxicity at the effective therapeutic dose, no liver damage was found in Ad-TK-122T group. Conclusions： miR-122-regulated TK expression achieved effective anti-tumor effects and increased the safety of intratumoral delivery of adenovirus-mediated TK/GCV gene therapy for miR-122-deficient HCC.

Safety and efficacy of microwave ablation for periductal hepatocellular carcinoma with intraductal cooling of the central bile ducts through a percutaneous transhepatic cholangial drainage tube

Background and aims:Biliary thermal injury caused by microwave ablation(MWA)for a hepatocellular carcinoma(HCC)close to the central bile ducts always results in severe complications and leads to mortality.Some studies have demonstrated that intraductal cooling of the biliary tract with chilled saline during thermal ablation can successfully prevent these complications.In this study,we present a novel bile duct cooling technique through a percutaneous transhepatic cholangial drainage(PTCD)tube for preventing biliary thermal injury caused by MWA,and compare the feasibility and safety of the intraductal cooling technique when performed with a PTCD tube and with an endoscopic nasobiliary drainage(ENBD)tube.Methods:Participants were randomly assigned to undergo MWA of HCC with intraductal chilled saline perfusion through a PTCD tube or an ENBD tube.The main study outcomes were bile duct complications related to MWA and local tumor recurrence,p value<0.05 was considered to indicate a statistically significant difference.Results:A total of 23 patients with an HCC(23 nodules)close to a central bile duct were enrolled in this study.Of these patients,12 had a PTCD tube and 11 had an ENBD tube placed into the hepatic duct close to the lesions.There were no PTCD-and ENBD-related mortality cases.There was no complication related to the PTCD procedure;however,3 patients(27.27%)developed acute pancreatitis and 1 patient(9.09%)had hemorrhage in the ENBD group(p=0.037).One patient(8.33%)in the PTCD group had bile leakage and 2 patients(18.18%)in the ENBD group developed a biloma.Within 5 years,1 patient in the PTCD group and 2 patients in the ENBD group had local recurrence.There was no significant difference in local recurrence,nonlocal hepatic recurrence,mortality rate,or median cumulative overall survival between the 2 groups.Conclusions:The intraductal cooling technique using a PTCD tube is a feasible and effective method for preventing bile duct thermal injury caused by MWA for an HCC close to the central bile ducts.It does not increase local recurrence and may be safer than intraductal cooling through an ENBD tube.

The Impact of Stream Landscape on Genetic Structure and Dispersal Patterns in Stream Salamander(Pachyhynobius shangchengensis)

Compared with other terrestrial environments,the stream environment generally presents a linear spatial structure and relatively simple environment.In a stream landscape,the dispersal direction of stream-type organisms usually presents a linear structure along the stream,which results in the limited dispersal and the genetic differentiation of stream-type organisms across different stream sections.The Shangcheng Stout Salamander(Pachyhynobius shangchengensis)is a narrowly distributed stream salamander in Dabie Mountains of East China.In the present study,we tested for the impact of stream landscape(i.e.waterfalls and underground river)on genetic structure and dispersal pattern in P.shangchengensis based on 12 nuclear microsatellite loci from 195 individuals in 3 populations(A,B and C)from three closely connected sections within one stream.Genetic diversity results suggested that Population B contains relatively high genetic diversity for P.shangchengensis when compared to the other populations(A and C).Detectable genetic differentiation was found(FST=0.008,P=0.007)among three populations,which was also supported by the Structure,FCA analysis and relatedness estimates of each pair of individuals among populations.The assignment test suggested that P.shangchengensis has philopatric males and female-biased dispersal(mean female Alc=.0.031,SE=0.225;mean male Alc=0.026,SE=0.198).Female-biased dispersal was also supported by analyses for each sex(i.e.Spatial autocorrelation,Genetic distance,Relatedness analysis).Our study indicated that small and isolated populations(A and C)had relatively low genetic diversity due to the limited population size.For stream salamanders,landscape features(i.e.waterfalls and underground river)can influence the ability of an individual to disperse through the landscape,and consequently influence the formation of strong genetic differentiation of P.shangchengensis.

Nest-site Use by the Chinese Alligator (Alligator sinensis) in the Gaojingmiao Breeding Farm,Anhui,China

Nest-site and nesting material used by the Chinese alligator （Alligator sinensis） was studied at the Gaojingmiao Breeding Farm, Langxi County, Anhui, China from May to September 2009. In this study, artificial nesting materials were placed in 43 potential nesting sites before the nesting season, 11 of which were used. Additionally, eight nests were built at natural sites without artificial nesting materials provided. Seven environmental variables were measured at each nest site： distance from water, height from water surface, sunlight duration, nearest bank slope, nest site slope, vegetation coverage and concealment. Statistical analyses indicated that concealment was significantly different between used and unused nest sites, with concealment being significantly correlated to the use of materials- placed sites. In comparing the nests at artificial vs. natural sites, only the nearest bank slope differed significantly. Further, principal component analysis of natural nests indicated that the duration of nest exposure to sunlight and vegetation coverage were more influential than the other factors studied.

ISSR Markers as a Tool for Assessing Genetic Diversity in the Chinese Alligator (Alligator sinensis)

Eight different inter simple sequence repeat(ISSR) markers were used as tools to investigate genetic variability and population differentiation in the Chinese alligator,Alligator sinensis,in this study. Eleven polymorphic bands(17.2%) out of a total of 64 were generated from 110 individuals in three populations. Analysis of molecular variation showed that most of the genetic variation(98.0%) occurred within the populations. Dendrogram relationship based on Nei’s unbiased genetic diversity illustrated that two breeding populations were genetically closely related. The Nm value of the study was 4.520,suggesting that high levels of gene flow existed and no differentiation appeared in the populations. In a reconstructed Neighbor-Joining tree,the haplotypes coming from the same populations did not gather as a class,suggesting the three populations had no apparent geographic pattern. This study shows that ISSR markers could be well applied as a feasible tool to assess genetic diversity in Chinese alligator individuals.

Unraveling the role of NiSnPH@OOH/CC perovskite hydroxide for efficient electrocatalytic oxidation of methanol to formate

The sluggish kinetics of oxygen evolution reaction(OER)is the key tailback for hydrogen production from the water electrolysis.Masking OER with thermodynamically auspicious methanol oxidation reaction(MOR)can significantly boost the H_(2) and value-added products production.However,it is currently challenging to achieve a synergistic manipulation of product selectivity and performance for MOR electrocatalyst.Herein,we report NiSnPH@OOH/CC(CC=carbon cloth)perovskite hydroxide nanosphere as an efficient MOR electrocatalyst with high activity,stability,and selectivity towards methanol oxidation to formate.A surface amorphous layer of defect rich NiOOH was generated in operando by selective Sn leaching with stable perovskite hydroxide bulk structure,which mitigates the oxidative power and optimizes the local coordination environment of the active NiOOH sites.In situ Raman combined with electrochemical studies further confirm the key active species,NiOOH,generated in operando enhance the MOR and blocking the over oxidation of methanol to CO_(2).As a result,NiSnPH@OOH/CC effectively masks the OER and attains>99%selectivity with 100%Faradic efficiency for methanol-to-formate.The results of this study show the advances of NiSnPH@OOH/CC as an efficient electrocatalyst for MOR and also suggest its potential applications for various small organic molecules oxidation.

西双版纳国家级自然保护区蚂蚁–树互作网络空间变异

网络分析(networkanalysis)可以同时分析群落中的物种多样性和种间关系,为了解生态群落的稳定性机制提供了新的分析思路和方法。本研究从西双版纳国家级自然保护区的纳板河、勐仑和勐腊(补蚌)三个地点采集了树栖性蚂蚁及树木的种类和数量数据,对蚂蚁–树组成的二分网络进行了分析,探讨了3个采样点物种的多样性、网络指标以及群落指标之间的关系。我们采用零模型的方法比较了3个样点的标准化网络参数差异。结果表明:蚂蚁和树木的物种数以及树的异质性指数(Shannon-Wiener多样性指数、Simpson多样性指数)都呈现出勐仑>纳板河>补蚌的趋势。树木–蚂蚁的灭绝曲线系数大小关系同样为勐仑>纳板河>补蚌,灭绝曲线与树的物种数及异质性指数大小趋势一致,而与蚂蚁的异质性指数并不吻合。根据Z值的绝对值来看,网络参数(加权嵌套性、平均连接数、特化水平、模块性、连接度)与群落参数(灭绝曲线系数、生态位重叠)的大小趋势相同,表现出勐仑>纳板河>补蚌的趋势。综上所述,蚂蚁–树互作网络的稳定性(灭绝曲线系数)主要由树的数量和异质性指数决定。网络的加权嵌套性和网络中节点的平均连接数也能促进群落的稳定性。而在一个特化的(数值越大表示专性互作越多)和模块化(具有较多密切互作的节点单元)的网络中,当低营养级物种灭绝时高营养级物种数量将迅速减少。

Laparoscopic cholecystectomy for double gallbladder

Double gallbladder is an embryological abnormality of relative rarity (1:4,000 human autopsies). Double gallbladder is often discovered accidentally or by complications of gallstones and cholecystitis. Herein, we present an unusual case of double gallbladder in which the cystic duct arises from the common bile duct separately and successfully treated cholecystitis with laparoscopic cholecystectomy.

Sequence variability analysis on major histocompatibility complex class Ⅱ DRB alleles in three felines

The variation of the exon 2 of the major histo-compatibility complex(MHC)class II gene DRB locus in three feline species were examined on clouded leopard(Neofelis nebulosa),leopard(Panthera pardus)and Amur tiger(Panthera tigris altaica).A pair of degenerated primers was used to amplify DRB locus covering almost the whole exon 2.Exon 2 encodes theβ1 domain which is the most vari-able fragments of the MHC class II molecule.Single-strand conformational polymorphism(SSCP)analysis was applied to detect different MHC class II DRB haplotypes.Fifteen recombinant plasmids for each individual were screened out,isolated,purified and sequenced finally.Totally eight distinct haplotypes of exon 2 were obtained in four individuals.With-in 237 bp nucleotide sequences from four samples,30 vari-able positions were found,and 21 putative peptide-binding positions were disclosed in 79 amino acid residues.The ratio of nonsynonymous substitutions(d_(N))was much higher than that of synonymous substitutions(d_(S)),which indicated that balancing selection probably maintain the variation of exon 2.MEGA neighbor joining(NJ)and PAUP maximum parsimo-ny(MP)methods were used to reconstruct phylogenetic trees among species,respectively.Results displayed a more close relationship between leopard and tiger;however,clouded leopard has a comparatively distant relationship form the other two.