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The study aims to identify the influences of sodium acetate on the growth, hematologic parameter, carbohydrate metabolism and gut microbiota of largemouth bass (Micropterus salmoides) fed high carbohydrate diets. The trial diets were formulated including the suitable carbohydrate (9 %, SC), the high carbohydrate (18 %, HCD) and HCD supplemented with 0.15 % sodium acetate (HCSD), and fed M. salmoides (initial body weight: 3.70 ± 0.06 g) for 8 weeks. The overcomes demonstrated compared to the SC group, the fish fed HCD exhibited metabolic abnormalities and liver damage accompanied with high levels of glucose (GLU), hepatosomatic index (HSI), aspartate aminotransferase (AST) and hepatic glycogen as well as high activities of phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6 phosphatase (G6P). However, inclusion of sodium acetate promoted the growth performance and lowered blood GLU and liver glycogen levels. Moreover, adding sodium acetate inhibited gluconeogenesis and promoted glycolysis via the Adenosine 5’-monophosphate (AMP)-activated protein kinase (AMPK) pathway. Additionally, in comparison with the HCD group, sodium acetate supplementation improved the composition of gut microbiota, inhibited the proportion of pathogens (Acinetobacter, Mycoplasma, Pseudomonas and Sediminibacterium) and increased the abundance of beneficial bacteria (Cetobacterium and Romboutsia). We concluded that sodium acetate mitigated effectively the adverse symptoms of M. salmoides fed HCD. More importantly, sodium acetate addition may improve the carbohydrate utilization by increasing the proportion of intestinal Cetobacterium and Romboutsia.

To investigate the effects of D-mannose on the growth performance, intestinal digestion capacity, intestinal microbiota composition, and ammonia tolerance of largemouth bass, experiments were conducted using largemouth bass fry with an average body weight of 7.41±0.05 g. Three experimental groups were designed, with 3 replicates per group and 30 fish per replicate. The fish were fed with feed containing different concentrations of D-mannose (0.00%, 1.00%, and 2.00% - Control, 1% mannose, 2% mannose) and were given full satiation twice a day for 56 days. The results indicated that the addition of 2% D-mannose in the feed enhanced the growth performance of the largemouth bass while reducing the feed conversion ratio. The addition of D-mannose in the feed increased the activity of digestive enzymes in the intestines (lipase, α-amylase, pepsin, alkaline phosphatase, Na+/K+ATPase, gamma-glutamyl transpeptidase, and creatine kinase). It also led to an increase in intestinal villi height and intestinal wall thickness; Adding D-mannose reduced the abundance of Staphylococcus and Achromobacter in the gut microbiota, while increasing the abundance of Aurantimicrobium. After being subjected to ammonia stress for 96 hours, the addition of D-mannose in the feed resulted in a decrease in mortality rate and neuronal nitric oxide synthase activity, while simultaneously enhancing the activity of liver argininosuccinate synthetase, argininosuccinate lyase, arginase, ornithine transcarboxylase, and inducible nitric oxide synthase. Adding D-mannose to the feed promotes the growth of largemouth bass, enhances their digestive capacity, and has a positive impact on their intestinal microbiota composition. Furthermore, it has been demonstrated that it can enhance the tolerance of largemouth bass to ammonia.

Seven graded levels of sodium propionate (SP) diets with 0 (SP1), 0.2% (SP2), 0.4% (SP3), 0.6% (SP4), 0.8% (SP5), 1.0% (SP6), and 1.2% (SP7) were prepared to feed Trachinotus ovatus (initial body weight: 8.64 ± 0.08 g) for 56 days. The results showed that increasing dietary SP levels quadratically increased significantly final body weight (FBW), weight gain rate (WGR), and specific growth rate (SGR) of T. ovatus but linearly and quadratically decreased significantly viscerosomatic index (VSI) and hepatosomatic index (HSI) of T. ovatus (P

Abstract Prostate cancer (PCa) is a frustrating immunogenic “cold” tumor and generally receives unsatisfied immunotherapy outcomes in the clinic. Pyroptosis is an excellent immunogenic cell death form that can effectively activate the antitumor immune response, promote cytotoxic T‐lymphocyte infiltration, and convert tumors from “cold” to “hot.” However, the in vivo application of pyroptosis drugs is seriously limited, and the upregulation of tumor PD‐L1 caused by photo‐immunotherapy further promotes immune escape. Herein, a new nano‐photosensitizer (YBS‐BMS NPs‐RKC) with pH‐response integrating immunogenic pyroptosis induction and immune checkpoint blockade is developed. The pH‐responsive polymer equipped with the cell membrane anchoring peptide RKC is used as the carrier and further encapsulated with the near‐infrared‐activated semiconductor polymer photosensitizer YBS and a PD‐1/PD‐L1 complex small molecule inhibitor BMS‐202. The pH‐driven membrane‐anchoring and pyroptosis activation of YBS‐BMS NPs‐RKC is clearly demonstrated. In vitro and in vivo studies have shown that this dual‐pronged therapy stimulates a powerful antitumor immune response to suppress primary tumor progression and evokes long‐term immune memory to inhibit tumor relapse and metastasis. This work provides an effective self‐synergistic platform for PCa immunotherapy and a new idea for developing more biocompatible photo‐controlled pyroptosis inducers.

The experiment was conducted to investigate the effects of dietary leucine on growth, antioxidant capacity, immune response, and inflammation in juvenile yellow catfish. Five diets were formulated to contain five dietary leucine levels: 12.00 (control), 19.00, 26.00, 33.00, and 40.00 g kg−1. Each diet was randomly assigned to triplicate groups of 30 juvenile fish (5.02 ± 0.15 g) twice daily to apparent satiation for 56 days. Weight gain rate, specific growth rate, and activities of liver superoxide dismutase, glutathione peroxidase, and serum lysozyme, as well as immunoglobulin M content, significantly increased with increase in dietary leucine levels up to 26.00 g kg−1, but those values decreased significantly with a further increase in dietary leucine. On the contrary, the lowest malondialdehyde content was found in 26.00 and 33.00 g kg−1 leucine groups. The expression levels of IGF 1 and MYF 5 genes in muscle were significantly upregulated with increase in dietary leucine levels up to 26.00 g kg−1, but the expression of MSTN level showed the opposite trend. The lowest expression levels of IL 8 and TNFɑ genes in the liver were found in 26.00 g kg−1 leucine groups. The quadratic regression analysis on weight gain, specific growth rate, and feed conversion ratio against dietary leucine levels indicated that the optimal dietary leucine requirement was estimated to be 26.84–27.00 g kg−1of the dry diet.

Abstract Purpose To develop and validate a preoperative cystoscopic-based predictive model for predicting postoperative high-grade bladder cancer (BCa), which could be used to guide the surgical selection and postoperative treatment strategies. Materials and methods We retrospectively recruited 366 patients with cystoscopy biopsy for pathology and morphology evaluation between October 2010 and January 2021. A binary logistic regression model was used to assess the risk factors for postoperative high-grade BCa. Diagnostic performance was analyzed by plotting receiver operating characteristic curve and calculating area under the curve (AUC), sensitivity, specificity. From January 2021 to July 2021, we collected 105 BCa prospectively to validate the model's accuracy. Results A total of 366 individuals who underwent transurethral resection of bladder tumor (TURBT) or radical cystectomy following cystoscopy biopsy were included for analysis. 261 (71.3%) had a biopsy pathology grade that was consistent with postoperative pathology grade. We discovered five cystoscopic parameters, including tumor diameter, site, non-pedicled, high-grade biopsy pathology, morphology, were associated with high-grade BCa. The established multi-parameter logistic regression model (“JSPH” model) revealed AUC was 0.917 (P

Abstract Background To investigate whether Pentafecta is suitable for bladder cancer patients receiving laparoscopic radical cystectomy (LRC). Methods From November 2013 to December 2020, muscle invasive Bladder Cancer (MIBC) and non-muscle invasive Bladder Cancer (NMIBC) patients who received LRC and urinary diversion were retrospectively analyzed. Pentafecta was defined as meeting five criteria: negative soft margin, ≥ 16 lymph nodes (LNs) removed, major complications free, urinary diversion related sequelae free and clinical recurrence free within 1 year. Analyze the achievement of five criteria and compare the overall survival (OS) of Pentafecta group with non-attainment group. Multivariable Cox’s regression was performed to evaluate the impact of Pentafecta on OS. Multivariable logistic regression was performed to explore the effect of surgical experience on Pentafecta attainment. Results A total of 340 patients were included, negative soft margin, ≥ 16 lymph nodes (LNs) removed, major complications free, urinary diversion related sequelae free and clinical recurrence free within 1 year were observed in 95.3%, 30.3%, 83.8%, 75.0% and 85.6% of patients, respectively. Pentafecta group had a significantly longer OS than the non-attainment group (P = 0.027). The group with 10–15 LNs removed and meeting the other four criteria had a similar OS to group with ≥ 16 LNs removed (Pentafecta group) (5-year OS: 67.3% vs 72.7%, P = 0.861). Pentafecta (HR = 0.33, P = 0.011), positive lymph nodes (HR = 2.08, P = 0.028) and MIBC (HR = 3.70, P

Introduction: Ammonia has been of concern for its high toxicity to animals. N-carbamylglutamate (NCG) can reduce blood ammonia levels in mammals, but studies on ammonia tolerance in fish are insufficient.Methods: Juvenile yellow catfish were fed two levels of NCG (0.00% and 0.05%) for 84 days under three ammonia levels (0.00, 0.08, and 0.16 mg/L NH3).Results and Discussion: The results showed that survival rate (SUR), final body weight (FBW), weight gain (WG), and serum total protein (TP), triglycerides (TG), glucose (Glu), ornithine (Orn), citrulline (Cit) contents, and liver superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), arginase (ARG), ornithine transcarbamylase (OTC) activities decreased with the increase of ammonia levels, on the contrary, feed conversion ratio (FCR), hepatosomatic index (HSI), and serum ammonia, urea, alanine aminotransferase (ALT), aspartate aminotransferase (AST), glutamine (Gln), arginine (Arg) contents, and liver malondialdehyde (MDA), tumor necrosis factor (TNF), interleukin (IL) 1, IL 8 contents, and mRNA expressions of cu/zn sod, cat, gpx, gr, tnf ɑ, il 1, and il 8 were significantly increased. Dietary 0.05% NCG supplementation had higher SUR, FBW, WG, feed intake (FI), whole-body protein, and serum TP, total cholesterol (TC), Glu, citrulline (Cit) contents, and liver SOD, GPx, argininosuccinate synthetase (ASS), argininosuccinate lyase (ASL), inducible nitric oxide synthase (iNOS) activities compared to 0.00% NCG group, but had lower serum ammonia, urea, ALT, AST, Gln, Arg contents, and liver MDA, TNF, IL 1, IL 8 contents, and neuronal nitric oxide synthase activity. At the end of bacterial challenge, cumulative mortality (CM) increased with ammonia levels increased, but serum antibody titer (AT), lysozyme (LYZ) activity, 50% hemolytic complement, immunoglobulin (Ig) contents, respiratory burst (RB), phagocytic indices decreased with ammonia levels increased. CM in 0.05% NCG group was lower than that in 0.00% NCG group, but serum AT, LYZ activity, Ig content, RB in 0.05% NCG group were significantly higher. The correlation analysis found that iNOS was positively correlated with ASS activity. This study indicates that dietary NCG supplementation can improve the ammonia tolerance of yellow catfish, and ASS may also be the target of NCG to activate the urea cycle.

Herein, a method was developed for the sensitive monitoring of carcinoembryonic antigen (CEA) by gold nanoparticles dotted prussian blue@polyaniline core-shell nanocubes (Au NPs/PB@PANI). First, a facile low-temperature method was used to prepare the uniform PB@PANI core-shell nanocubes with the assistance of PVP, where PB acted as the electron transfer mediator to provide electrochemical signals, and the PANI with excellent conductivity and desirable chemical stability not only played the role of a protective layer to prevent etching of PB in basic media but also effectively improved electron transfer. Importantly, to further enhance the electrical conductivity and biocompatibility of PB@PANI and to further enhance the electrochemical signal and capture a large amount of Ab2, Au NPs were doped on the surface of PB@PANI to form Au NPs/PB@PANI nanocomposites. Subsequently, benefiting from the advantages of core-shell structure nanoprobes and gold-platinum bimetallic nanoflower (AuPt NF), a sandwich-type electrochemical immunosensor for CEA detection was constructed, which provided a wide linear detection range from 1.0 pg·mL−1 to 100.0 ng·mL−1 and a low detection limit of 0.35 pg·mL−1 via DPV (at 3σ). Moreover, it displayed a satisfactory result when the core-shell structure nanoprobe-based immunosensor was applied to determine CEA in real human serum samples.

Abstract Since the breakthrough discoveries of DNA and histone modifications, the field of RNA modifications has gained increasing interest in the scientific community. The discovery of N6-methyladenosine (m6A), a predominantly internal epigenetic modification in eukaryotes mRNA, heralded the creation of the field of epi-transcriptomics. This post-transcriptional RNA modification is dynamic and reversible, and is regulated by methylases, demethylases and proteins that preferentially recognize m6A modifications. Altered m6A levels affect RNA processing, degradation and translation, thereby disrupting gene expression and key cellular processes, ultimately resulting in tumor initiation and progression. Furthermore, inhibitors and regulators of m6A-related factors have been explored as therapeutic approaches for treating cancer. In the present review, the mechanisms of m6A RNA modification, the clinicopathological relevance of m6A alterations, the type and frequency of alterations and the multiple functions it regulates in different types of cancer are discussed.

PurposeTo investigate the role of circulating rare cells (CRCs), namely, circulating tumor cells (CTCs) and circulating endothelial cells (CECs), in aiding early intervention, treatment decision, and prognostication in bladder cancer.MethodsA total of 196 patients with pathologically confirmed bladder cancer, namely, 141 non-muscle invasive bladder cancer (NMIBC) and 55 muscle invasive bladder cancer (MIBC) patients. There were 32 patients who received cisplatin-based neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC). Subtraction enrichment combined with immunostaining-fluorescence in situ hybridization (SE-iFISH) strategy was used for CTC/CEC detection. Kaplan–Meier analysis and Cox regression were used to evaluate the overall survival (OS) and recurrence-free survival (RFS). Receiver operator characteristic analysis was used to discriminate NAC sensitivity.ResultsCTCs and CECs were related to clinicopathological characteristics. Triploid CTCs, tetraploid CTCs, and total CECs were found to be higher in incipient patients than in relapse patients (P = 0.036, P = 0.019, and P = 0.025, respectively). The number of total CECs and large cell CECs was also associated with advanced tumor stage (P = 0.028 and P = 0.033) and grade (P = 0.028 and P = 0.041). Remarkably, tumor-biomarker-positive CTCs were associated with worse OS and RFS (P = 0.026 and P = 0.038) in NMIBC patients underwent TURBT. CECs cluster was an independent predictor of recurrence in non-high-risk NMIBC patients underwent TURBT (HR = 9.21, P = 0.040). For NAC analysis, pre-NAC tetraploid CTCs and small cell CTCs demonstrated the capability in discriminating NAC-sensitive from insensitive patients. Additionally, tetraploid CTCs and single CTCs elevated post-NAC would indicate chemoresistance.ConclusionCTCs and CECs may putatively guide in diagnosis, prognosis prediction, and therapeutic decision-making for bladder cancer.

Ammonia is toxic to most fish. Different fish have different treatment methods for ammonia toxicity, mainly including urea cycle and glutamine synthesis pathway, depending on their physiological status. A two-stage study was carried out to test the inhibition of argininosuccinate synthase (ASS) effects on ammonia detoxification in hyperammonemia yellow catfish. At the stage 1, fish were injected lethal half concentration (LC50) of ammonium acetate and sampled at 0, 1, 3, 6, 12 and 24 h post-injection. The result found that plasma ammonia content of fish was injected with ammonium acetate reached its highest level at hour 1, which was used as the optimal sampling time in stage 2. At the stage 2, the four experimental groups were carried out: NaCl group was injected intraperitoneally with 0.9% sodium chloride as control; NH3 group was injected with LC50 ammonium acetate; NH3+BPP group was injected with mixture of ammonium acetate and bradykinin-potentiating peptide (BPP); BPP group was injected with BPP. The results showed that inhibition of ASS can lead to accumulation of ammonia in plasma and kidney, and glutamine in liver and kidney; and decreases ASS, argininosuccinate lyase, arginase activates, and ornithine, glutamate, alanine, proline, tyrosine, methionine contents, and increases ornithine transcarbamylase, glutaminase activates, and citrulline, aspartate, arginine, glutamine, histidine, isoleucine, phenylalanine, lysine contents; and result in upregulation of ASS, ASL, CPS 1, OTC, GS and GLS genes expression. This result indicates that the inhibition of ASS in yellow catfish with ammonia poisoning will lead to the urea cycle disorder; yellow catfish can enhance the detoxification capacity of ammonia by improving glutamine synthesis when the urea cycle is inhibited; argininase played an important role in ammonia detoxification of yellow catfish.

BackgroundRadical cystectomy (RC) is the standard treatment for muscular invasive bladder cancer (MIBC) and some high-risk non-muscular invasive bladder cancer (NMIBC). Cutaneous ureterostomy is a common form of urinary diversion. However, after radical cystectomy, recurrence of upper urinary tract malignancies is possible. There is no relevant report on how to improve this situation’s management.Case PresentationThis case is a 56-year-old male patient hospitalized due to the development of a new tumor in the ureteral cutaneous stoma following radical cystectomy for more than five years. A biopsy of the tumor revealed high-grade urothelial carcinoma. Computed tomography (CT) revealed that the local soft tissue around the cutaneous stoma was thickened, but no other lesions were visible. After evaluating the case, we chose robot-assisted completely intracorporeal resection of cutaneous ureterostomy tumor and ileal conduit surgery. The total time for the operation and the blood loss were 400 minutes and 150 ml, respectively. Following surgery, the patient got standard chemotherapy in combination with immunotherapy. Additionally, ten months following the surgery, the patient did not experience disease progression or complications.ConclusionThe robot-assisted operation is safe and feasible for upper urinary tract tumor recurrence following radical cystectomy with cutaneous ureterostomy.

A simple, sensitive, and fluorescent immunoassay for the detection of prostate-specific antigen (PSA) based on horseradish peroxidase and silicon dioxide nanospheres as a signal amplification strategy has been described. In the design, the primary antibody (Ab1) of PSA was first immobilized on the 96-well plates via physical adsorption between polystyrene and hydrophobic groups of the antibody molecule. The silicon dioxide nanospheres (SiO2 NSs), with large surface area and good biocompatibility, were loaded with horseradish peroxidase (HRP) and horseradish peroxidase-labeled secondary antibodies (HRP-Ab2) as signal amplification systems. In the presence of PSA, a sandwich-type immunocomplex composed of Ab1-Ag-HRP-Ab2 had been formed. Fluorescence technology was employed to obtain the response signal of the immunoassay in the L-tyrosine and H2O2 systems. Experiment results showed that a strong and stable fluorescent signal at 416 nm (excitation wavelength: 325 nm) was observed, and the changes in fluorescent intensity were related to the levels of PSA. Under the optimal conditions, the relative fluorescence intensity was linear with the logarithm of PSA concentration from 0.03 to 100 ng·mL−1, with a detection limit of 0.01 ng·mL−1 (at a signal/noise ratio of 3). In contrast to other fluorescent immunoassays, the sandwich-type immunoreaction based on the high binding ELISA plates has the advantages of being simple, stable, and easy to operate, high selectivity, small sample quantity, etc., which can be widely used in the selective detection of a variety of targets, from DNA to proteins and small molecules. Such fluorescent immunoassays should be feasible for the fields of molecular diagnosis and other life science fields in the future.

IntroductionCircular RNAs (circRNAs) are non-coding RNAs that have the structure of a covalently closed loop. Increasing data have proven that circRNAs can influence the progression and chemotherapy sensitivity of tumors. Therefore, the underlying function and mechanisms of more circRNAs in progression and chemotherapy resistance are important.MethodsWe conducted RNA sequencing on five pairs of urothelial carcinoma samples and screened for circRNAs. CircFAM114A2 was found to be low expressed in urothelial carcinoma. The functions of circFAM114A2 in urothelial carcinoma were explored by cell cycle assay, IC50 determination assay, cell proliferation assay, apoptosis assay, and tumorigenesis assay.ResultsWe discovered that the levels of circFAM114A2 were decreased in urothelial carcinoma cell lines and tissues. According to follow-up data, urothelial carcinoma patients with higher circFAM114A2 expression had better survival. Importantly, the levels of circFAM114A2 were associated with the histological grade of urothelial carcinoma. CircFAM114A2 could inhibit cell proliferation and block more urothelial carcinoma cells in the G1 phase and then increase the sensitivity of urothelial carcinoma to cisplatin chemotherapy. Mechanistically, circFAM114A2 directly sponged miR-222-3p/miR-146a-5p and subsequently influenced the expressions of the downstream target genes P27/P21, which, in turn, inhibited the progression of urothelial carcinoma and increased the sensitivity of cancer cells to cisplatin chemotherapy.ConclusionCircFAM114A2 could inhibit progression and promote cisplatin sensitivity in urothelial carcinoma through novel circFAM114A2/miR-222-3p/P27 and circFAM114A2/miR-146a-5p/P21 pathways. CircFAM1142 has therefore great potential as a prognostic biomarker and therapeutic target for urothelial carcinoma.

Abstract In this paper, we present a family of conjugate gradient projection methods for solving large-scale nonlinear equations. At each iteration, it needs low storage and the subproblem can be easily solved. Compared with the existing solution methods for solving the problem, its global convergence is established without the restriction of the Lipschitz continuity on the underlying mapping. Preliminary numerical results are reported to show the efficiency of the proposed method.

Effects of dietary Polychlorinated biphenyl (PCB) exposure and dietary vitamin A supplementation on Chinese mitten crab Eriocheir sinensis were studied with the aim to explain dietary PCB toxicity and toxic alleviation by vitamin A intake in crab. Four diets were used including three experimental diets containing 0, 80000 or 240000 IU/kg vitamin A with each experimental diet containing 10 mg PCB/kg diet, and a control diet (without vitamin A and PCB supplementation) in 56 days feeding trial. Crabs fed the PCB-only diet had significantly lower weight gain than those fed the control diet. No significant difference was observed in crab survival among all groups. Crabs fed the PCB-only diet had a significantly higher malondialdehyde content and antioxidase superoxide dismutase activity in the serum and hepatopancreas, and higher erythromycin N-demethylase and glutathione S-transferase activities in the hepatopancreas than those fed the control diet. However, supplementation of dietary vitamin A decreased the levels of all these parameters. The hepatopancreatic cytochrome P450 2 and 4 (CYP2, CYP4), fatty acid binding proteins 3 and 10 (FABP3, FABP10) and intracellular lipolytic enzyme (IL) Messenger Ribonucleic Acid (mRNA) levels in the PCB-only group were significantly higher than those in the control group, and dietary 240000 IU/kg vitamin A supplementation decreased hepatopancreatic CYP4, FABP3, FABP10 and IL enzyme mRNA level. The crabs fed 80000 IU/kg vitamin A supplementation diet had the highest level of retinoid X receptor mRNA in the hepatopancreas. The structure of the hepatopancreas was damaged and the deposit of lipid droplets decreased with dietary PCB exposure. Both levels of vitamin A supplementation alleviated the damage and increased lipid droplets in the hepatopancreas. Dietary PCB exposure significantly reduced total hemocyte count (THC), and phenoloxidase, acid phosphatase activities in the serum. Post-challenge survival of crab in the experimental PCB-only diet group was low compared with that in the control. Supplementation of 240000 IU/kg vitamin A significantly increased the THC and phenoloxidase activity in the serum and post-challenge survival compared with those in the PCB-only group. This study indicates that dietary vitamin A can improve the antioxidant capacity, immune response, detoxification enzymes activities, energy metabolism and hepatopancreas tissue structure of Chinese mitten crab fed PCB contaminated diets.

espl1 (extra spindle pole bodies like 1), a cysteine endopeptidase, is a mitotic key player in chromosomal segregation and centriole duplication during mitosis and meiosis. Considering the espl1 gene has not been reported in aquatic organisms, we reported the isolation and expression of the espl1 gene from loach. In this study, the full-length cDNA of espl1 was cloned for the first time in loach. In loach, the full-length cDNA of espl1 consisted of 6948 bp, the open reading frame (ORF) is 6240 bp, and the espl1 gene encodes 2139 amino acids. Moreover, the deduced amino acid sequences of espl1 in loach shared the highest identity with those of Cyprinus carpio (78.39%) and Sinocyclocheilus anshuiensis (78.27%), and the sequence homology among the various separases is confined to the C-terminal region. Furthermore, tissue-specific checking results indicated that the espl1 gene of the loach gene was highly expressed in the ovary and testis, especially in stage IV oocytes and stage IV testis by Real-time quantitative PCR (qPCR). Then, whole-mount in situ hybridization analyses revealed the expression of espl1 in the early development of loach. We found that the positive signal of espl1 was observed in the notochord during the early embryo development of loach. Last but not least, when treated with luteinizing hormone-releasing hormone analog (LHRH-A2), the mRNA expression of espl1 was significantly increased in the testes and ovaries. These observations suggest that the espl1 gene had a distinct and important role in the gonads of Loach. This study will be of value for further studies into the function of the espl1 gene in fish. [ABSTRACT FROM AUTHOR]