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The Yangtze River is the mother river of China. To promote the aquatic ecosystem protection of the great river, the Project of Yangtze Fisheries Resources and Environment Investigation (2017–2021) supported by the Ministry of Agriculture and Rural Affairs, P. R. China carried out by 24 institutes and universities that located in the Yangtze River basin surveys the status of (1) fish species composition and spatial distribution, (2) current fish abundance, (3) endangered fishes, (4) Yangtze finless porpoise, (5) aquatic eco-environments, (6) water-level fluctuation areas, (7) capture fisheries and recreational fisheries of the Yangtze River mainstream and 10 of its main tributaries, including Yalong River, Heng River, Min River (including Dadu River), Chishui River, Tuo River, Jialing River, Wu River, Han River, Dongting Lake and Poyang Lake. The results showed that there were 443 fish species (belonging to 163 genus, 37 families, and 18 orders) before 2017, but only 323 fish species (including 15 new recorded exotic species) were recorded in the project of 2017–2021. Among them, Cyprinus carpio, Carassius auratus, Hypophthalmichthys molitrix, Pelteobagrus fulvidraco, Coilia brachygnathus, Silurus asotus, Saurogobio dabryi, Ctenopharyngodon idellus, Pelteobagrus nitidus, Hemiculter leucisculus, Siniperca chuatsi, Coreius heterodon, Culter alburnus, Parabramis pekinensis, and Aristichthys nobilis were the dominant species across the whole Yangtze River system. It is estimated that there were 886 million individuals weighing 124.8 million kg, merely equivalent to 27.3% of the resources in 1950s, 30.9% of the resources in 1960s, or 58.7% of the resources in 1980s. In the new list of protected fishes that recorded in the Yangtze River system, only 15 of 29 were collected in this project of 2017–2021. Psephurus gladius has been affirmed to be Extinct by International Union for Conservation of Nature (IUCN). The wild individuals of Tenualosa reevesii and Luciobrama macrocephalus have disappeared for many years and maybe have been extinct already. Acipenser dabryanus has been affirmed to be Extinct in the Wild by IUCN. The natural propagations of A. sinensis, Myxocyprinus asiaticus and Trachidermus fasciatus have been interrupted for many years. The populations of Yangtze finless porpoise in the Yangtze River mainstream, Dongting Lake and Poyang Lake have steadily rising sizes and expanding distributions in 2017–2021. Parts of them migrate from one region to another with the seasons, which would result in the fluctuation of Yangtze finless porpoise population within some regions. The conventional indicators of water quality in the Yangtze River system were good and conformed to the water quality criteria of fishery in 2017–2021. In the last 40 years, the maximum surface water area in the Yangtze River basin extended to approximately 63,360 km2, the minimum surface water area covered approximately 26,396 km2, and the seasonal water-level fluctuation areas occupied approximately 36,964 km2. Compared with 1984–2000 period, the 2001–2020 period witnessed an overall decreasing trend in the frequency of surface water occurrence within about 25,869 km2 of aquatic areas. From 1984 to 2000 period to 2001–2020 period, permanent surface water has decreased by nearly 8,750 km2. In 2017, the fishermen were mainly 40–60 years old and their educational levels were mainly lower than junior high school. In 2017, most anglers were older than 40 and used hand rod and/or sea rod. Their average catch of each time was mainly less than 1 kg. Results suggested that the fishing ban in key waters of the Yangtze River basin is not only an ecological project of aquatic ecosystem conservation, but also a livelihood project for the fisherman to embrace industrial transformation and improve their living conditions. After the implementation of the fishing ban, the fisheries resources would gradually recover, and the Yangtze finless porpoise population size would also see a steady increase. However, the endangered species would remain threatened for a long time. The degraded waterbodies and water-level fluctuation areas would be the key restrictive factors for future aquatic ecosystem recovery in the Yangtze River basin. Since this survey was carried out before the fishing ban, the current results could provide a baseline for future evaluation of the effect of the Yangtze River fishing ban.

Zinc oxide nanoparticles (ZnO NPs) measuring 30 ± 10 nm in diameter are utilized in various applications, including batteries, plastics, ceramics, cosmetics, flame retardants, and food. However, their potential impact and risk on aquatic ecosystems remain unclear. This study examined the hepatotoxic effects of dietary ZnO NPs in rare minnow. Three hundred rare minnows were fed diets containing 0 mg/kg, 20 mg/kg and 60 mg/kg of ZnO NPs for 60 days, with hepatotoxicity assessments at 15-day intervals. The histological data showed that ZnO NPs severely damage liver tissues, causing cytoplasmic vacuolization and irregular or missing nuclei. The treatment groups showed a significant rise in the liver injury index (P < 0.05). Moreover, there was a notable increase in zinc accumulation in the ZnO NPs groups compared to the control group (P < 0.05). ZnO NPs also reduced body weight and hepato-somatic index (HSI) in rare minnows. The enzyme activity results showed elevated levels of reactive oxygen species (ROS), total cholesterol (T-CHO), triglyceride (TG), acetyl Coa carboxylase (ACC), and fatty acid synthase (FAS) in the ZnO NPs fed groups, while total antioxidant capacity (T-AOC) and malondialdehyde (MDA) decreased. Further investigation found that accumulation of ZnO NPs in the liver tissues up-regulated the levels of genes related to antioxidant (mn-sod, cat and nf-κb), pro-apoptotic (bax) and lipogenesis (gpat3, dgat1a and dgat1b), while down-regulating genes associated with lipid catabolism (cpt1 and tpi1). These findings suggest that dietary ZnO NPs cause hepatotoxicity by inducing oxidative stress through ROS, triggering apoptosis, and inhibiting lipid peroxidation. The results indicate that ZnO NPs may pose a significant threat to aquatic animals and ecosystems.

In recent years, zinc oxide nanoparticles (ZnO NPs) have gained attention as feed additives due to their high bioavailability. However, research on their impact on fish growth and health is limited. To investigate the influences of dietary addition of ZnO NPs on growth performance and immune function of rare minnow, rare minnows were fed diets with different ZnO NPs content. Growth analysis showed that ZnO NPs had a negative effect on the weight of rare minnow, decreasing and then increasing condition factors (CFs) and specific growth rate. Additionally, the accumulated zinc (Zn) level was significantly higher (p

Prostate stromal cells can contribute to prostate tumorigenesis. Here the authors show that the loss of androgen receptor signalling in Gli1-lineage stromal cells diminishes prostate epithelial oncogenic transformation and tumor growth in mouse models and this is due to insulin-like growth factor binding protein 3-mediated inhibiting IGF1 and Wnt/β-catenin signalling activation.

Understanding the patterns and ecological determinants of β diversity in freshwater ecosystems is fundamental to biogeography, conservation biology, and environmental management. It has been proposed that β diversity can be divided into contributions of individual sites (LCBD) or species (SCBD) to total β diversity. However, the patterns and underlying mechanisms of LCBD and SCBD remain understudied in freshwater fish. Here, using fish assemblages sampled from the Chishui River basin, we analysed β diversity based on both abundance and presence-absence data. We also examined the relationships between LCBD and SCBD with site (i.e., community abundance, species richness, functional diversity indices, environmental factors, and spatial variables) and species (i.e., occupancy, total abundance, niche position and breadth, and functional traits) characteristics, respectively. Our results revealed that fish LCBD in the Chishui River basin was well explained by both environmental and spatial factors. Fish LCBD was negatively related to species richness and community abundance, showing that sites with high ecological uniqueness generally supported low fish richness and abundance. Furthermore, functional features of fish assemblages were also significantly associated with LCBD, with high LCBD associated with high functional specialization, originality, and uniqueness, but low functional richness, divergence, and dispersion. Abundance-based SCBD showed positive relationships with both occupancy and total abundance, whereas there were hump-shaped relationships between presence-absence SCBD and occupancy and total abundance. Niche position was negatively correlated with SCBD, whereas niche breadth and functional traits were not significant correlates of SCBD. Overall, this study suggests that understanding contributions of sites and species to β diversity is key to understanding biodiversity variation and its applied repercussions. Our results advocate the importance of environmental conditions and between-site connectivity for effective conservation of riverine fish diversity. Moreover, a simultaneous application of LCBD, species richness, SCBD, and rare species would be the most suitable approach for biodiversity conservation.

Microplastics are ubiquitous in the natural environment, especially in waters, and their potential impact is also a key issue of concern. In this study, we used 1 µm, 1000 μg/L, polystyrene (PS-MPs) particles to analyze the effects after exposure for 14 and 28 days in rare minnow (Gobiocypris rarus). Results indicated that PS-MPs induce structural alterations in the intestinal tissue, including epithelial damage, villi damage and the inflammatory cell infiltration, while the changes were severer after exposure for 28 days. Polystyrene microplastics also significantly increased the activities of catalase (CAT, increased 142 % and 385 % in 14d and 28d), superoxide dismutase (SOD, increased 17.76 % and 23.43 % in the 14d and 28d) and the content of malondialdehyde (MDA, increased 14.5 % and 442 % in the 14d and 28d), glutathione (GSH, increased 146 % and 298 % in the 14d and 28d). The results not only showed the characterization of gut microbial communities in rare minnow, but also indicated that microbial diversity and composition were altered in gut of fish exposed to PS-MPs. In the control groups, Proteobacteria (31.36–54.54 %), Actinobacteriota (39.99–52.54 %), Fusobacteriota (1.43–1.78 %), Bacteriadota (0.31–0.57 %) were the four dominant bacterial phyla in the intestinal of rare minnow. After exposure to microplastics, In the gut microbiota, the proportion of Proteobacteria increased 9.27 % and 30 % with exposure time, while Actinobacteria decreased 37.89 % and significantly different after 28 days. In addition, metabolomic analysis suggested that exposure to PS-MPs induced alterations of metabolic profiles in rare minnow and differential metabolites were involved in energy metabolism, inflammatory responsible secretion, oxidative stress, nucleotide and its metabolomics. In conclusion, our findings suggest that long-term exposure to microplastics could induce intestinal inflammation, oxidative stress, microbiota dysbiosis and metabolic disorder in rare minnow, and the alterations and severity were exacerbated by prolonged exposure. This study has extended our cognition of the toxicity of polystyrene, and enriched theoretical data for exploring the toxicological mechanism of microplastics.

This study proposes a newly designed ignition circuit that does not change the ignition starting parameters of a Hall thruster, reduces the critical ignition voltage, and improves ignition reliability. The complexity and weight of the Hall thruster power supply system are reduced by multiplexing the ignition and discharge power supplies. Under the condition that the design parameters are satisfied, that is, R3+REC2 is much larger than RCC1, the residual energy in the circuit after the cathode breakdown can be fed into the thruster discharge channel to improve the ignition energy supply. The experimental results show that when the anode voltage is 98 V, only nine of the 100 ignition tests are successful using the traditional ignition circuit, whereas the number of successes using the newly designed ignition circuit is as high as 99, which provides a simple solution method for improving the ignition reliability.

Background and AimsEmergency endoscopy is recommended for patients with acute esophageal variceal bleeding (EVB) and their prognosis has improved markedly over past decades due to the increased specialization of endoscopic practice. The study aimed to compare outcomes following emergency endoscopic injection sclerotherapy (EIS) and endoscopic variceal ligation (EVL) in cirrhotic patients with acute EVB.MethodsCirrhotic patients with acute EVB who underwent emergency endoscopy were retrospectively enrolled from 2013 to 2020 across 34 university hospitals from 30 cities. The primary outcome was the incidence of 5-day rebleeding after emergency endoscopy. Subgroup analysis was stratified by Child-Pugh class and bleeding history. A 1:1 propensity score matching (PSM) analysis was performed.ResultsA total of 1,017 and 382 patients were included in EIS group and EVL group, respectively. The 5-day rebleeding incidence was similar between EIS group and EVL group (4% vs. 5%, P = 0.45). The result remained the same after PSM (P = 1.00). Among Child-Pugh class A, B and C patients, there were no differences in the 5-day rebleeding incidence between the two groups after PSM (P = 0.25, 0.82, and 0.21, respectively). As for the patients with or without bleeding history, the differences between EIS group and EVL group were not significant after PSM (P = 1.00 and 0.26, respectively).ConclusionThe nationwide cohort study indicates that EIS and EVL are both efficient emergency endoscopic treatment strategies for acute EVB. EIS should not be dismissed as an economical and effective emergency endoscopic treatment strategy of acute EVB. ClincialTrials.gov number NCT04307264.

Summary: Thymic carcinoma is rare and has a poorer prognosis than thymomas. The treatment options are limited after failure of platinum-based chemotherapy. We previously performed a single-center phase II study of pembrolizumab in patients with advanced thymic carcinoma, showing a 22.5% response rate. Here, we characterize the genomic and transcriptomic profile of thymic carcinoma samples from 10 patients (5 non-responders versus 5 responders) in this cohort, with the main aim of identifying potential predictors of response to immunotherapy. We find that expression of PDL1 and alterations in genes or pathways that correlated with PD-L1 expression (CYLD and BAP1) could be potential predictors for response or resistance to immunotherapy in patients with advanced thymic carcinoma. Our study provides insights into potential predictive markers/pathways to select patients with thymic carcinoma for anti-PD-1 immunotherapy.

Schizothorax kozlovi, as an endemic and vulnerable fish of the upper Yangtze River in China, faces many threats. In order to expose the population structure of wild S. kozlovi, the carbon and oxygen isotopic ratios in the otoliths, and the gene sequences of two common mitochondrial markers (Cytb and COI) were investigated in four sampling locations, and then their relationship with ambient temperature was further investigated. In general, it exhibits limited geographic population structuring of S. kozlovi in the upper Yangtze River by both mtDNA and stable isotopes. The values of otolith stable isotope ratios varied from −15.30‰ to −12.37‰ for δ18O and from −10.10‰ to −6.13‰ for δ13C. Significant relationships were revealed between stable isotope ratios and specific mean monthly water temperature variables (from November to March), indicating low temperature effect on otolith stable isotope ratios. Haplotype diversity and nucleotide diversity were 0.928 and 0.00778, both exhibiting high levels. A median-joining haplotype network indicated a mixture of geographical distribution but exhibited two distinct haplotype lineages (Clade I and Clade II). AMOVA detected that the higher percentage of genetic variance was within sampling locations (96.94%) and between two haplotype lineages (72.82%). Most FST values between sampling locations showed small levels of genetic differentiation except the differentiation between population SJ (Sanjiangkou) and JP (Jinping). Therefore, two haplotype lineages and population JP of S. kozlovi in the upper Yangtze River are suggested as three management units for conservation due to their moderate-to-great genetic differentiation and isolated habitat.

Environmental enrichment is a method to increase environmental heterogeneity, which may reduce stress and improve animal welfare. Previous studies have shown that environmental enrichment can increase the growth rate, decrease aggressive and anxiety-like behaviors, improve learning ability and agility, and reduce cortisol levels in animals. These effects usually differ between species. Unfortunately, habitat enrichment on laboratory fish is poorly studied and seldom adopted in care guidance. Rare minnows (Gobiocypris rarus) have been cultured as a native laboratory fish in China in barren banks without environmental enrichment since 1990; they have been widely used in studies on ecotoxicology, environmental science, and other topics. The purpose of this study was to investigate the effect of environment enrichment on the growth, physiological status, and anxiety-like behavior of laboratory rare minnows. We observed and analyzed SGR, cortisol levels, DA, DOPAC, 5-HT and 5-HIAA, and anxiety-like behavior indexes after one month of treatment in barren (control) and enrichment tanks. We found that there were no significant differences in SGR, anxiety-like behavior, DA, DOPAC, or 5-HIAA levels between the two treatments. However, higher cortisol and 5-HT levels were observed in the enrichment tanks. This study suggests that rare minnows might be influenced by their living environment, and future related studies should consider their environmental enrichment.

The complete mitochondrial DNA genome of Anabarilius brevianalis was determined. The entire mitochondrial genome is 16,610 bp in length and contains 13 protein-coding genes, 2 ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes, and 1 control region (CR). The gene arrangement, gene numbers, base composition, and codon usage pattern of this species were similar to the typical Cultrinae fish mitochondrial genomes. Maximum likelihood phylogenetic analysis based on the complete mitochondrial sequence shows the A. brevianalis clustered with A. grahami are closely related to Hemiculter branch within the subfamily Cultrinae.

Prostate embryonic development, pubertal and adult growth, maintenance, and regeneration are regulated through androgen signaling-mediated mesenchymal-epithelial interactions. Specifically, the essential role of mesenchymal androgen signaling in the development of prostate epithelium has been observed for over 30 years. However, the identity of the mesenchymal cells responsible for this paracrine regulation and related mechanisms are still unknown. Here, we provide the first demonstration of an indispensable role of the androgen receptor (AR) in sonic hedgehog (SHH) responsive Gli1-expressing cells, in regulating prostate development, growth, and regeneration. Selective deletion of AR expression in Gli1-expressing cells during embryogenesis disrupts prostatic budding and impairs prostate development and formation. Tissue recombination assays showed that urogenital mesenchyme (UGM) containing AR-deficient mesenchymal Gli1-expressing cells combined with wildtype urogenital epithelium (UGE) failed to develop normal prostate tissue in the presence of androgens, revealing the decisive role of AR in mesenchymal SHH responsive cells in prostate development. Prepubescent deletion of AR expression in Gli1-expressing cells resulted in severe impairment of androgen-induced prostate growth and regeneration. RNA-sequencing analysis showed significant alterations in signaling pathways related to prostate development, stem cells, and organ morphogenesis in AR-deficient Gli1-expressing cells. Among these altered pathways, the transforming growth factor β1 (TGFβ1) pathway was up-regulated in AR-deficient Gli1-expressing cells. We further demonstrated the activation of TGFβ1 signaling in AR-deleted prostatic Gli1-expressing cells, which inhibits prostate epithelium growth through paracrine regulation. These data demonstrate a novel role of the AR in the Gli1-expressing cellular niche for regulating prostatic cell fate, morphogenesis, and renewal, and elucidate the mechanism by which mesenchymal androgen-signaling through SHH-responsive cells elicits the growth and regeneration of prostate epithelium.

E-cadherin complexes with the actin cytoskeleton via cytoplasmic catenins and maintains the functional characteristics and integrity of the epithelia in normal epithelial tissues. Lost expression of E-cadherin disrupts this complex resulting in loss of cell polarity, epithelial denudation and increased epithelial permeability in a variety of tissues. Decreased expression of E-cadherin has also been observed in invasive and metastatic human tumors. In this study, we investigated the effect of E-cadherin loss in prostatic epithelium using newly developed genetically engineered mouse models. Deletion of E-cadherin in prostatic luminal epithelial cells with modified probasin promoter driven Cre (PB-Cre4) induced the development of mouse prostatic intraepithelial neoplasia (PIN). An increase in levels of cytoplasmic and nuclear β-catenin appeared in E-cadherin deleted atypical cells within PIN lesions. Using various experimental approaches, we further demonstrated that the knockdown of E-cadherin expression elevated free cytoplasmic and nuclear β-catenin and enhanced androgen-induced transcription and cell growth. Intriguingly, pathological changes representing prostatic epithelial cell denudation and increased apoptosis accompanied the above PIN lesions. The essential role of E-cadherin in maintaining prostatic epithelial integrity and organization was further demonstrated using organoid culture approaches. To directly assess the role of loss of E-cadherin in prostate tumor progression, we generated a new mouse model with bigenic Cdh1 and Pten deletion in prostate epithelium. Early onset, aggressive tumor phenotypes presented in the compound mice. Strikingly, goblet cell metaplasia was observed, intermixed within prostatic tumor lesions of the compound mice. This study provides multiple lines of novel evidence demonstrating a comprehensive role of E-cadherin in maintaining epithelial integrity during the course of prostate oncogenic transformation, tumor initiation and progression.

The tumor suppressor p16Ink4a, encoded by the INK4a gene, is an inhibitor of cyclin D-dependent kinases 4 and 6, CDK4 and CDK6. This inhibition prevents the phosphorylation of the retinoblastoma protein (pRb), resulting in cellular senescence through inhibition of E2F-mediated transcription of S phase genes required for cell proliferation. The p16Ink4a plays an important role in tumor suppression, whereby its deletion, mutation, or epigenetic silencing is a frequently observed genetic alteration in prostate cancer. To assess its roles and related molecular mechanisms in prostate cancer initiation and progression, we generated a mouse model with conditional deletion of p16Ink4a in prostatic luminal epithelium. The mice underwent oncogenic transformation and developed prostatic intraepithelial neoplasia (PIN) from eight months of age, but failed to develop prostatic tumors. Given the prevalence of aberrant androgen signaling pathways in prostate cancer initiation and progression, we then generated R26hARL/wt:p16L/L: PB-Cre4 compound mice, in which conditional expression of the human AR transgene and deletion of p16Ink4a co-occur in prostatic luminal epithelial cells. While R26hARL/wt:PB-Cre4 mice showed no visible pathological changes, R26hARL/wt:p16L/L: PB-Cre4 compound mice displayed an early onset of high-grade PIN (HGPIN), prostatic carcinoma, and metastatic lesions. Strikingly, we observed tumors resembling human sarcomatoid carcinoma with intermixed focal regions of signet ring cell carcinoma (SRCC) in the prostates of the compound mice. Further characterization of these tumors showed they were of luminal epithelial cell origin, and featured characteristics of epithelial to mesenchymal transition (EMT) with enhanced proliferative and invasive capabilities. Our results not only implicate a biological role for AR expression and p16Ink4a deletion in the pathogenesis of prostatic SRCC, but also provide a new and unique genetically engineered mouse (GEM) model for investigating the molecular mechanisms for SRCC development.

Glyptothorax deqinensis is a small endangered Sisoridae fish mainly distributed in the southwest of China. In the present study, the complete mitochondrial genome of G. deqinensis was firstly sequenced. The total length of the G. deqinensis mitogenome is 16,542 bp, including 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes, and a control region. Among these genes, 28 are encoded by the H-strand and 9 by the L-strand. The information mitogenome obtained herein will provide useful tools for future studies on population genetic and phylogenetic analyses of this fish.

Pseudecheneis immaculatus is an endemic fish species in the Lantsang River. In this study, the complete mitochondrial genome sequence of P. immaculatus was determined and analyzed. The 16,432 bp long circular molecule consisted of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region, and all genes show the typical gene arrangement conforming to the vertebrate consensus. The phylogenetic tree showed that P. immaculatus is closely related to P. sulcata. The present study can provide population genetics information for further exploration of the taxonomic status of P. immaculatus.

The leucine zipper tumor suppressor 2 (LZTS2) was identified as a tumor susceptibility gene within the 10q24.3 chromosomal region, and is approximately 15Mb from the PTEN locus. This region containing the both loci is frequently deleted in a variety of human malignancies, including prostate cancer. LZTS2 is a ß-catenin-binding protein and a negative regulator of Wnt signaling. Overexpression of PTEN in prostate cancer cell lines reduces ß-catenin-mediated transcriptional activity. In this study, we examined the collaborative effect of PTEN and LZTS2 using multiple in vitro and in vivo approaches. Co-expression of PTEN and LZTS2 in prostate cancer cells shows stronger repressive effect on ß-catenin mediated transcription. Using a newly generated mouse model, we further assessed the effect of simultaneous deletion of Pten and Lzts2 in the murine prostate. We observed that mice with both Lzts2 and Pten deletion have an earlier onset of prostate carcinomas as well as an accelerated tumor progression compared to mice with Pten or Lzts2 deletion alone. Immunohistochemical analyses show that atypical and tumor cells from compound mice with both Pten and Lzts2 deletion are mainly composed of prostate luminal epithelial cells and possess higher levels of cytoplasmic and nuclear β-catenin. These cells also exhibit a higher proliferative capacity than cells isolated from single deletion mice. These data demonstrate the significance of simultaneous Pten and Lzts2 deletion in oncogenic transformation in prostate cells and implicates a new mechanism for the dysregulation of Wnt/β-catenin signaling in prostate tumorigenesis.

Bladder cancer represents a significant human tumor burden, accounting for about 7.7% and 2.4% of all cancer cases in males and females, respectively. While men have a higher risk of developing bladder cancer, women tend to present at a later stage of disease and with more aggressive tumors. Previous studies have suggested a promotional role of androgen signaling in enhancing bladder cancer development. To directly assess the role of androgens in bladder tumorigenesis, we have developed a novel transgenic mouse strain, R26hARLoxP/+:Upk3aGCE/+, in which the human AR transgene is conditionally expressed in bladder urothelium. Intriguingly, both male and female R26hARLoxP/+:Upk3aGCE/+ mice display a higher incidence of urothelial cell carcinoma (UCC) than the age and sex matched control littermates in response to the carcinogen, N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). We detect expression of the human AR transgene in CK5-positive and p63-positive basal cells in bladder urothelium. Further analyses of UCC tissues from R26hARLoxP/+:Upk3aGCE/+ mice showed that the majority of tumor cells are of urothelial basal cell origin. Positive immunostaining of transgenic AR protein was observed in the majority of tumor cells of the transgenic mice, providing a link between transgenic AR expression and oncogenic transformation. We observed an increase in Ki67 positive cells within the UCC lesions of transgenic AR mice. Manipulating endogenous androgen levels by castration and androgen supplementation directly affected bladder tumor development in male and female R26hARLoxP/+:Upk3aGCE/+ mice, respectively. Taken together, our data demonstrate for the first time that conditional activation of transgenic AR expression in bladder urothelium enhances carciongen-induced bladder tumor formation in mice. This new AR transgenic mouse line mimics certain features of human bladder cancer and can be used to study bladder tumorigenesis and for drug development.

Based on sparse representation, a robust global and local classification algorithm for visual target tracking in uncertain environment was proposed in this paper. The global region of target and the position of target would be found, respectively by the proposed algorithm. Besides, overcompleted dictionary was obtained and updated by biased discriminate analysis with the divergence of positive and negative samples at current frame. And this over-completed dictionary not only discriminates the positive samples accurately but also rejects the negative samples effectively. Experiments on challenging sequences with evaluation of the state-of-the-art methods show that the proposed algorithm has better robustness to illumination changes, perspective changes, and targets rotation itself.

Polysaccharides from marine clams perform various biological activities, whereas information on structure is scarce. Here, a water-soluble polysaccharide MMPX-B2 was isolated from Meretrix meretrix Linnaeus. The proposed structure was deduced through characterization and its immunological activity was investigated. MMPX-B2 consisted of d-glucose and d-galctose residues at a molar ratio of 3.51:1.00. The average molecular weight of MMPX-B2 was 510 kDa. This polysaccharide possessed a main chain of (1→4)-linked-α-d-glucopyranosyl residues, partially substituted at the C-6 position by a few terminal β-d-galactose residues or branched chains consisting of (1→3)-linked β-d-galactose residues. Preliminary immunological tests in vitro showed that MMPX-B2 could stimulate the murine macrophages to release various cytokines, and the structure-activity relationship was then established. The present study demonstrated the potential immunological activity of MMPX-B2, and provided references for studying the active ingredients in M. meretrix.