Cellular mechanism underlying leptin-induced anion secretion of rat epididymal epithelial cells.

BACKGROUND: A large number of studies have shown that leptin plays an important role in the regulation of fertility via the hypothalamus-pituitary-gonad axis. However, its peripheral function in epididymis was still elusive. OBJECTIVE: The purpose of this study was to determine the pro-secretion effect of leptin on the rat epididymal epithelium. MATERIALS AND METHODS: In the present study, real-time quantitative polymerase chain reaction, western blot, and immunohistochemical analysis were employed to detect the expression pattern of leptin receptors in rat epididymis. The pro-secretion effect of leptin on epididymal epithelial cells was measured by short-circuit current, and the prostaglandin E2 and cyclic adenosine monophosphate level was evaluated by enzyme-linked immunosorbent assay. RESULTS: We verified that the leptin receptor was located on the epididymal epithelium, with a relatively high expression level in corpus and cauda epididymis. Ussing chamber experiments showed that leptin stimulated a significant rise of the short-circuit current in rat epididymal epithelial cells, which could be abolished by the specific leptin receptor antagonist peptide Allo-aca, or by removing the ambient Cl- and HCO3 -. Furthermore, the leptin-stimulated short-circuit current response could be abrogated by blocking the apical cystic fibrosis transmembrane regulator or the basolateral Na+-K+-2Cl- cotransporter. Our pharmacological experiments manifested that interfering with the prostaglandin H synthase-2-prostaglandin E2-EP2/EP4-adenylate cyclase pathways could significantly blunt the cystic fibrosis transmembrane regulator-mediated anion secretion induced by leptin. The enzyme-linked immunosorbent assay demonstrated that leptin could induce a substantial increase in prostaglandin E2 release and cyclic adenosine monophosphate synthesis of primary cultured rat cauda epididymal epithelial cells. Our data also suggested that JAK2, ERK, and PI3K-dependent phosphorylation may be involved in the activation of prostaglandin H synthase-2 and the subsequent prostaglandin E2 production. CONCLUSIONS: The present study demonstrated the pro-secretion function of leptin in rat epididymal epithelium via the activation of cystic fibrosis transmembrane regulator and Na+-K+-2Cl- cotransporter, which was dependent on the paracrine/autocrine prostaglandin E2 stimulated EP2/EP4-adenylate cyclase pathways, and thus contributed to the formation of an appropriate microenvironment essential for sperm maturation.

In Silico Design of Heterogeneous Microvascular Trees Using Generative Adversarial Networks and Constrained Constructive Optimization.

OBJECTIVE: Designing physiologically adequate microvascular trees is of crucial relevance for bioengineering functional tissues and organs. Yet, currently available methods are poorly suited to replicate the morphological and topological heterogeneity of real microvascular trees because the parameters used to control tree generation are too simplistic to mimic results of the complex angiogenetic and structural adaptation processes in vivo. METHODS: We propose a method to overcome this limitation by integrating a conditional deep convolutional generative adversarial network (cDCGAN) with a local fractal dimension-oriented constrained constructive optimization (LFDO-CCO) strategy. The cDCGAN learns the patterns of real microvascular bifurcations allowing for their artificial replication. The LFDO-CCO strategy connects the generated bifurcations hierarchically to form microvascular trees with a vessel density corresponding to that observed in healthy tissues. RESULTS: The generated artificial microvascular trees are consistent with real microvascular trees regarding characteristics such as fractal dimension, vascular density, and coefficient of variation of diameter, length, and tortuosity. CONCLUSIONS: These results support the adoption of the proposed strategy for the generation of artificial microvascular trees in tissue engineering as well as for computational modeling and simulations of microcirculatory physiology.

Estimates on age, growth, and mortality of Leuciscus chuanchicus (Kessler 1876) in the Ningxia section of the upper reaches of the Yellow River, China.

To investigate the age structure, growth pattern, mortality and exploitation rates of Leuciscus chuanchicus in the upstream Ningxia section of the Yellow River, four sampling surveys were conducted between 2022 and 2023. A total of 472 individuals were measured for their total length (TL) and body weight (W). Age determination was performed using otoliths. The collected samples had a range of total lengths from 4.52 to 37.45 cm, body weights ranging from 0.68 to 552.43 g, and ages ranging from 1 to 7 years old. The relationship between total length and body weight was expressed as W = 0.0052 L3.19 for all samples, which indicates that the growth of L. chuanchicus adheres to allometry. The Von Bertalanffy growth equation revealed that the fish had an asymptotic total length (L∞) of approximately 37.9 cm with a growth coefficient (K) value of approximately 0.461 yr-1. Using the age-based catch curve method, the calculated total instantaneous mortality rate (Z) for all samples was determined as being equal to approximately 1.1302 yr-1. Additionally, three methods were used to estimate the average instantaneous rate of natural mortality (M), resulting in an approximate value of 0.7167 yr-1 for all samples. Furthermore, the instantaneous rate of fishing mortality (F) for all samples was calculated as 0.4134 yr-1, leading us to determine that the exploitation rate (E) is 0.3658. It was concluded that the growth rate of L. chuanchicus in the upstream of the Yellow River is relatively fast, and L. chuanchicus has not been subjected to excessive exploitation, yet its relatively high natural mortality rate underscores the need for targeted management measures aimed at preserving its habitat.

A comparative study on the age, growth, and mortality of Gobio huanghensis (Luo, Le & Chen, 1977) in the Gansu and Ningxia sections of the upper Yellow River, China.

BALKGROUND: Gobio huanghensis is a small economic fish endemic to the Yellow River at the junction of the Tibetan Plateau and the Huangtu Plateau in China. To understand the impact of environmental changes and human activities on the ecological structure of the G. huanghensis population, a comparative study was conducted on the age composition, growth characteristics, mortality rate, and exploitation rate of the G. huanghensis populations in the Gansu and Ningxia sections of the upper Yellow River. RESULTS: During the investigation, a total of 1147 individuals were collected, with 427 individuals collected from the Gansu section and 720 individuals from the Ningxia section. The results showed that G. huanghensis in the Gansu section exhibited a total length ranging from 5.00 to 22.80 cm, with an average of 12.68 ± 4.03 cm. In the Ningxia section, the total length of G. huanghensis ranged from 2.15 to 20.65 cm, with an average of 9.48 ± 3.56 cm. The age composition of G. huanghensis in the Gansu section ranged from 1 to 7 years, where female fish were observed between 1 and 7 years old, and male fish between 1 and 6 years old. In the Ningxia section, both female and male fish ranged from 1 to 5 years old. The relationships between total length and body weight were (Gansu section, R2 = 0.9738) and (Ningxia section, R2 = 0.9686), indicating that fish in the Gansu section exhibit positive allometric growth, while fish in the Ningxia section exhibit negative allometric growth. The von Bertalanffy growth equation revealed that G. huanghensis in the Gansu section exhibited an asymptotic total length L∞ of 27.426 cm with a growth coefficient K of 0.225 yr-1, while in the Ningxia section, the asymptotic total length L∞ was 26.945 cm with a growth coefficient K of 0.263 yr-1. The total mortality rate (Z) values of G. huanghensis were 0.7592 yr and 1.1529 yr in the Gansu section and Ningxia section, respectively. The average natural mortality rate (M), estimated by three different methods, in the Gansu section was 0.4432 yr, while it was 0.5366 yr in the Ningxia section. The exploitation rate (E) of G. huanghensis was 0.4163 in the Gansu section and 0.5345 in the Ningxia section, indicating that the population in the Ningxia section may have been overexploited. CONCLUSION: Prolonged fishing pressures and environmental changes may have led to variations in the ecological parameters of the G. huanghensis population between the Gansu and Ningxia sections.

Feasibility of simultaneous TMJ arthroscopy in ADDwoR patients undergoing orthognathic surgery for jaw deformity.

This study evaluated the feasibility of simultaneous temporomandibular joint (TMJ) arthroscopy and orthognathic surgery as a new treatment strategy for anterior disc displacement without reduction (ADDwoR) patients with severe jaw deformities. Twelve ADDwoR patients with facial deformities who underwent arthroscopy and orthognathic surgery between September 2015 and December 2019 were retrospectively evaluated. Pre- and postoperative maximum incisal opening (MIO) and joint pain were recorded. Computed tomography (CT) and three-dimensional cephalometric analysis were performed at 3 (T1) and ≥6 (T2) months postoperatively. Magnetic resonance imaging (MRI) of the TMJ was performed before, ≤7 days after and ≥6 months after surgery. The lateral profile radiological findings, the symmetry of the maxilla and mandible, and the MRI measurements were compared. Anterior disc displacement did not recur, and the maximum incisal opening (MIO) increased from 27.4 mm to 32.7 mm after surgery (p < 0.05). No significant differences were found in the lateral profile, symmetry indices or condylar height via MRI between T1 and T2. Joint morphology and the position of both the maxilla and mandible remained stable during postoperative follow-up, while joint symptoms were markedly relieved and facial appearance was noticeably improved. Combined arthroscopy and orthognathic surgery is effective and recommended for ADDwoR patients with jaw deformities.

Amino acid-based supramolecular chiral hydrogels promote osteogenesis of human dental pulp stem cells via the MAPK pathway.

Critical-size defects (CSDs) of the craniofacial bones cause aesthetic and functional complications that seriously impact the quality of life. The transplantation of human dental pulp stem cells (hDPSCs) is a promising strategy for bone tissue engineering. Chirality is commonly observed in natural biomolecules, yet its effect on stem cell differentiation is seldom studied, and little is known about the underlying mechanism. In this study, supramolecular chiral hydrogels were constructed using L/d-phenylalanine (L/D-Phe) derivatives. The results of alkaline phosphatase expression analysis, alizarin red S assay, as well as quantitative real-time polymerase chain reaction and western blot analyses suggest that right-handed D-Phe hydrogel fibers significantly promoted osteogenic differentiation of hDPSCs. A rat model of calvarial defects was created to investigate the regulation of chiral nanofibers on the osteogenic differentiation of hDPSCs in vivo. The results of the animal experiment demonstrated that the D-Phe group exhibited greater and faster bone formation on hDPSCs. The results of RNA sequencing, vinculin immunofluorescence staining, a calcium fluorescence probe assay, and western blot analysis indicated that L-Phe significantly promoted adhesion of hDPSCs, while D-Phe nanofibers enhanced osteogenic differentiation of hDPSCs by facilitating calcium entry into cells and activate the MAPK pathway. These results of chirality-dependent osteogenic differentiation offer a novel therapeutic strategy for the treatment of CSDs by optimising the differentiation of hDPSCs into chiral nanofibers.

Age, growth, reproduction and mortality of Xenocypris argentea (Günther,1868) in the lower reaches of the Tangwang River, China.

To investigate various population biological parameters of Xenocypris argentea in the lower reaches of the Tangwang River (China), a comprehensive study was conducted for the first time. A total of 1,003 samples were collected from April to November 2022. The collected samples revealed that female X. argentea had total lengths ranging from 12.4 cm to 25.7 cm (weighing 15.86 g to 159.55 g), and male X. argentea had total lengths ranging from 10.8 cm to 23.9 cm (weighing 9.27 g to 121.06 g). The age of the samples was determined using otolith analysis, indicating that the ages ranged from 1 to 5 years old in both females and males. The length-weight relationships were further analyzed, uncovering the allometric growth index (b) was 3.1296 for females, indicating a positive allometric growth pattern. Differently, males exhibited a b value of 3.0274, suggesting an isometric growth pattern. Furthermore, the von Bertalanffy growth formula provided insights into the growth characteristics of X. argentea, revealing an asymptotic total length (L∞) of 36.096 cm and a growth coefficient (K) of 0.121. The analysis of the gonadal somatic index (GSI) and ovarian development period indicated that the spawning period occurred from April to July, with peak spawning in June. The study also explored fecundity-related traits, finding that individual absolute fecundity (FA) ranged from 11,364 eggs to 56,377 eggs, while eviscerated body weight relative fecundity (FW) ranged from 209 eggs/g to 823 eggs/g. The exploitation rate (E) for X. argentea was calculated as 0.574, suggesting that the population of X. argentea has been overexploited. By revealing previously unknown data on the key life history traits of X. argentea, this study has provided valuable insights that are crucial for the development of conservation strategies and policies.

Shish-kebab structure fiber with nano and micro diameter regulate macrophage polarization for anti-inflammatory and bone differentiation.

Biopolymer grafts often have limited biocompatibility, triggering excessive inflammatory responses similar to foreign bodies. Macrophage phenotype shifts are pivotal in the inflammatory response and graft success. The effects of the morphology and physical attributes of the material itself on macrophage polarization should be the focus. In this study, we prepared electrospun fibers with diverse diameters and formed a shish-kebab (SK) structure on the material surface by solution-induced crystallization, forming electrospun fiber scaffolds with diverse pore sizes and roughness. In vitro cell culture experiments demonstrated that SK structure fibers could regulate macrophage differentiation toward M2 phenotype, and the results of in vitro simulation of in vivo tissue reconstruction by the microenvironment demonstrated that the paracrine role of M2 phenotype macrophages could promote bone marrow mesenchymal stem cells (BMSCs) to differentiate into osteoblasts. In rats implanted with a subcutaneous SK-structured fiber scaffold, the large-pore size and low-stiffness SK fiber scaffolds demonstrated superior immune performance, less macrophage aggregation, and easier differentiation to the anti-inflammatory M2 phenotype. Large pore sizes and low-stiffness SK fiber scaffolds guide the morphological design of biological scaffolds implanted in vivo, which is expected to be an effective strategy for reducing inflammation when applied to graft materials in clinical settings.

Effects of regular aerobic exercise on vascular function in overweight or obese older adults: A systematic review and meta-analysis.

Background: Overweight and obese older adults have a high risk for developing cardiovascular disease. Aerobic exercise is a valuable strategy to improve vascular health, but the effects of aerobic exercise on vascular endothelial function in obese and overweight older adults remain controversial. The purpose of this meta-analysis was to investigate the effects of aerobic exercise on vascular function in obese and overweight older adults with or without comorbidity. Methods: A systematic literature search for related studies published in English was conducted between January 1989 and October 30, 2022, in the PubMed, Embase, and Cochrane Library databases. A random effects model was chosen for meta-analysis, which calculated the effect sizes of control and intervention groups after exercise intervention using standardized mean differences (SMDs) corrected for Hedges' g bias and 95% confidence intervals (95% CIs). Results: Twenty-six studies containing 1418 participants were included in the study. After excluding three studies contributing to higher heterogeneity by sensitivity analysis, there are small effects of regular aerobic exercise on vascular function of obese and overweight older adults, including flow-mediated dilation (FMD) [SMD = 0.21, 95% CI (0.02, 0.41), z = 2.16, df = 19, I2 = 52.2%, P = 0.031] and pulse wave velocity (PWV) [SMD = -0.24, 95% CI (-0.46, -0.02), z = 2.17, df = 10, I2 = 8.6%, P = 0.030], and no significant effect was observed on augmentation index (Aix). Subgroup analysis showed small effects of regular aerobic exercise on FMD [SMD = 0.37, 95% CI (0.13, 0.61), z = 3.05, df = 9, I2 = 52.6%, P = 0.002] in the overweight not obese subgroup (25 = BMI <30 kg/m2), but no significant effect on the obese subgroup (BMI ≥30 kg/m2). Regular aerobic exercise for more than 24 weeks improved FMD by small effect sizes [SMD = 0.48, 95% CI (0.04, 0.93), z = 2.12, df = 5, I2 = 56.4%, P = 0.034] and for more than three times per week improved FMD by moderate effect sizes [SMD = 0.55, 95% CI (0.12, 0.98), z = 2.50, df = 3, I2 = 31.1%, P = 0.012] in obese and overweight older adults with or without CVD. Conclusion: In obese and overweight older adults with or without comorbidity, regular aerobic exercise for more than 24 weeks improved FMD by small effect sizes and exercise for more than three times per week improved FMD by moderate effect sizes and regular aerobic exercise reduced PWV by small effect sizes and had no influence on Aix. Taken together, it was recommended that obese and overweight older adults should adhere to regular aerobic exercise, training at least 3 times per week for better results.

Facile synthesis of aluminosilicate zeolites with STT, CHA and MWW topology structures.

Efficient synthesis of zeolites with different topologies is of great significance for both fundamental research and industrial application. Herein, the SSZ-23 zeolite, an odd zeolite containing 7-membered ring (7-MR) and 9-MR channels, has been synthesized under fluorine-free conditions via the route of pre-aging and pH regulation. By this novel synthesis route, the crystallization time can be significantly shortened to 3 days, nearly half as that by the conventional route in fluoride media. The pH value of the aging gel, i.e., the basicity, is found to play a key role in the synthesis, as SSZ-13 and SSZ-25 zeolites can be synthesized simply by changing the basicity of the same aging gel. Characterization results indicate that decreasing the basicity can promote the condensation between Si and Si/Al species and thus increase the framework density of the resulting zeolites. Finally, the dimethyl ether (DME) carbonylation reaction is employed to evaluate the catalytic properties of the above three zeolites with an identical chemical composition, and to reveal the unique confinement effect in various zeolite topologies.

Aerobic exercises regulate the epididymal anion homeostasis of high-fat diet-induced obese rats through TRPA1-mediated Cl- and HCO3- secretion†.

Aerobic exercises could improve the sperm motility of obese individuals. However, the underlying mechanism has not been fully elucidated, especially the possible involvement of the epididymis in which sperm acquire their fertilizing capacity. This study aims to investigate the benefit effect of aerobic exercises on the epididymal luminal milieu of obese rats. Sprague-Dawley male rats were fed on a normal or high-fat diet (HFD) for 10 weeks and then subjected to aerobic exercises for 12 weeks. We verified that TRPA1 was located in the epididymal epithelium. Notably, aerobic exercises reversed the downregulated TRPA1 in the epididymis of HFD-induced obese rats, thus improving sperm fertilizing capacity and Cl- concentration in epididymal milieu. Ussing chamber experiments showed that cinnamaldehyd (CIN), agonist of TRPA1, stimulated an increase of the short-circuit current (ISC) in rat cauda epididymal epithelium, which was subsequently abolished by removing the ambient Cl- and HCO3-. In vivo data revealed that aerobic exercises increased the CIN-stimulated Cl- secretion rate of epididymal epithelium in obese rats. Pharmacological experiments revealed that blocking cystic fibrosis transmembrane regulator (CFTR) and Ca2+-activated Cl- channel (CaCC) suppressed the CIN-stimulated anion secretion. Moreover, CIN application in rat cauda epididymal epithelial cells elevated intracellular Ca2+ level, and thus activate CACC. Interfering with the PGHS2-PGE2-EP2/EP4-cAMP pathway suppressed CFTR-mediated anion secretion. This study demonstrates that TRPA1 activation can stimulate anion secretion via CFTR and CaCC, which potentially forming an appropriate microenvironment essential for sperm maturation, and aerobic exercises can reverse the downregulation of TRPA1 in the epididymal epithelium of obese rats.

Improving delivery efficiency using spots and energy layers reduction algorithms based on a large momentum acceptance beamline.

BACKGROUND: Intensity-modulated proton therapy (IMPT) is a well-known delivery method of proton therapy. Besides higher plan quality, reducing the delivery time is also essential to IMPT plans. It can enhance patient comfort, reduce treatment costs, and improve delivery efficiency. From the perspective of treatment efficacy, it contributes to mitigating the intra-fractional motions and improving the accuracy of radiotherapy, especially for moving tumors. PURPOSE: However, there is a tradeoff problem between the plan quality and delivery time. We consider the potential of a large momentum acceptance (LMA) beamline and apply the spots and energy layers reduction method to reduce the delivery time. METHODS: The delivery time for each field consists of the energy layer switching time, spot traveling time, and dose delivery time. The larger momentum spread and higher intensity beam offered by the LMA beamline contribute to reducing the total delivery time compared to the conventional beamline. In addition to the dose fidelity term, an L1 and logarithm items were added to the objective function to increase the sparsity of the low-weighted spots and energy layers. After that, the low-weighted spots and layers were iteratively excluded in the reduced plan, which reduced the energy layer switching time and spot traveling time. We used the standard, reduced, and LMA-reduced plans to validate the proposed method and tested it on prostate and nasopharyngeal cases. Then, we compared and evaluated the plan quality, treatment time, and plan robustness against delivery uncertainty. RESULTS: Compared with the standard plans, the number of spots in the LMA-reduced plans was on average reduced by 13 400 (95.6%) for prostate cases and by 48 300 (80.7%) for nasopharyngeal cases and the number of energy layers was on average reduced by 49 (61.3%) for prostate cases and by 97 (50.5%) for nasopharyngeal cases. And, the delivery time of the LMA-reduced plans was shortened from 34.5 to 8.6 s for prostate cases and from 163.8 to 53.6 s for nasopharyngeal cases. The LMA-reduced plans had comparable robustness to the spot monitor unit (MU) error compared with the standard plans, but the LMA-reduced plans became more sensitive to spot position uncertainty. CONCLUSION: The delivery efficiency can be significantly improved using the LMA beamline and spots and energy layers reduction strategies. The method is promising to improve the efficiency of motion mitigation strategies for treating moving tumors.

Biochemical indices, gene expression, and SNPs associated with salinity adaptation in juvenile chum salmon (Oncorhynchus keta) as determined by comparative transcriptome analysis.

Chum salmon (Oncorhynchus keta) migrate from freshwater to saltwater, and incur developmental, physiological and molecular adaptations as the salinity changes. The molecular regulation for salinity adaptation in chum salmon is currently not well defined. In this study, 1-g salmon were cultured under 0 (control group, D0), 8‰ (D8), 16‰ (D16), and 24‰ (D24) salinity conditions for 42 days. Na+/K+-ATPase and Ca2+/Mg2+-ATPase activities in the gill first increased and then decreased in response to higher salinity environments where D8 exhibited the highest Na+/K+ATPase and Ca2+/Mg2+-ATPase activity and D24 exhibited the lowest. Alkaline phosphatase (AKP) activity was elevated in all salinity treatment groups relative to controls, while no significant difference in acid phosphatase (ACP) activity was observed across treatment groups. De novo transcriptome sequencing in the D0 and D24 groups using RNA-Seq analysis identified 187,836 unigenes, of which 2,143 were differentially expressed in response to environmental salinity (71 up-regulated and 2,072 down-regulated). A total of 56,020 putative single nucleotide polymorphisms (SNPs) were also identified. The growth, development, osmoregulation and maturation factors of N-methyl-D-aspartate receptors (nmdas) expressed in memory formation, as well as insulin-like growth factor 1 (igf-1) and igf-binding proteins (igfbps) were further investigated using targeted qRT-PCR. The lowest expression of all these genes occurred in the low salinity environments (D8 or D16), while their highest expression occurred in the high salinity environments (D24). These results provide preliminary insight into salinity adaptation in chum salmon and a foundation for the development of marker-assisted breeding for this species.

Impact of absent crowds on technical and physical performances in the Chinese Soccer Super League.

Purpose: Spectators have a significant impact on match performances in soccer, but to what extent crowd support contributes to the technical and physical performances remains unclear. This study aimed to (1) investigate the differences in terms of technical and physical performances with and without spectators; and (2) identify the key factors differentiating between win and loss when playing with and without the presence of an audience. Methods: Our study examined 794 performance records from 397 matches during the 2019-2020 seasons in the Chinese Soccer Super League. The least absolute shrinkage and selection operator (LASSO)-logistic regression was utilized to select significant predictors. Using an independent t-test and the Mann-Whitney non-parametric test explores the difference between matches with and without spectators. Key factors between win and loss were explored using univariate and multivariate logistic regression analyses. Results: Our study found that cross (p < 0.01, ES = -0.24), shots (p < 0.001, ES = -0.25), and shot accuracy (p < 0.05, ES = -0.18) displayed decreasing trends whereas sprint distances (p < 0.05, ES = 0.16) presented an increasing trend without spectators comparing with the crowd support. Moreover, the above three technical variables were the main factors differentiating between wins and losses. Similarly, team and opponent quality remained important potential factors affecting the match outcome. Conclusion: Match outcome or team performance is determined by a myriad of factors, but there are clear differences in technical and physical performances between matches with and without the presence of an audience. Similarly, our study provides a better explanation for the impact of crowd support on match performances whereby coaches can deploy players and adjust match strategies for ultimate success.

Sequencing and analysis of the complete mitochondrial genome of Gymnogobius laevis.

Gymnogobius laevis (Steindachner, 1879) is a small, benthic freshwater fish. In a previous study, it was reported as a rare resident in Heilongjiang Province. In this study, the mitochondrial genome of G. laevis was sequenced. It is 16,519 base pairs (bp) in length and contains 13 protein-coding genes, two ribosomal RNA genes (12S rRNA and 16S rRNA), 22 transfer RNA genes (tRNA), and two non-coding control regions. The A + T content is 55.71% in the G. laevis mitochondrial genome. A phylogenetic tree shows that G. laevis is closely related to the family Gobiinae based on complete mitogenome sequences.

A model of the pulmonary acinar circulatory system with gas exchange function to explore the influence of alveolar diameter.

Lung diseases such as acute respiratory distress syndrome affect the patient's lung compliance, which in turn affects the ability of gas exchange. Changes in alveolar diameter relate to local lung compliance. How alveolar diameter affects gas exchange, particularly oxygen concentrations in alveolar capillaries, is a topic of concern for researchers, and can be studied using mathematical models. The level of small-scale mathematical models of the pulmonary circulatory system was the alveolar capillaries, but existing models do not consider the gas-exchange function and fail to reflect the influence of alveolar diameter. Therefore, we proposed a pulmonary acinar capillary model with gas exchange function, and most importantly, introduced alveolar diameter into the model, to analyze the effect of alveolar diameter on the gas exchange function of the pulmonary acini. The model was tested by three respiratory function simulation experiments. According to the simulation results of changing diameter, we found that the alveolar diameter mainly affects the alveolar gas exchange function of lung acinar inlets and the middle section compared with the peripheral section.

Mechanosensitive Piezo1 channel in rat epididymal epithelial cells promotes transepithelial K+ secretion.

The Piezo1 channel, a mechanosensitive channel that exhibit a preference for Ca2+, play multifarious physiological and pathological roles in the endothelium and epithelium of various tissues. However, the functional expression of Piezo1 channel in the epithelium of the male reproductive tract remains unknown. In the present study, the expression of Piezo1 channel in the rat epididymis was determined by real-time quantitative PCR, western blot and immunohistochemical analysis. Our data revealed that Piezo1 channel was located in the epithelial layer of the rat epididymis, with higher expression levels in the corpus and cauda regions. The pro-secretion function of Piezo1 channel was then investigated using short circuit current (ISC) and intracellular Ca2+ imaging techniques. Application of Yoda1, a selective Piezo1 channel activator, stimulated a remarkable decrease in the ISC of the epididymal epithelium. Pharmacological experiments revealed that the ISC response induced by Piezo1 channel activation was abolished by pretreating epithelial cells with the Yoda1 analogue, Dooku1, the selective mechanosensitive cation channel blocker, GsMTx4, or removal of basolateral K+. Meanwhile, we demonstrated that activation of Piezo1 channel triggered a robust Ca2+ influx in epididymal epithelial cells. The possible involvement of Ca2+- activated K+channels (KCa) in transepithelial K+ secretion was then evaluated. And that big conductance KCa (BK), but not small conductance or intermediate conductance KCa, mediated Piezo1-elicited transepithelial K+ secretion. Moreover, we demonstrated that NKCC and NKA were responsible for supplying substrate K+ during transepithelial K+ secretion. These data demonstrate that the activation of Piezo1 channel promotes BK-mediated transepithelial K+ secretion, and thus may plays an important role in the formation of a high K+ concentration in epididymal intraluminal fluid.

Estimation of Coregonus ussuriensis age, growth, and maturation in China's Amur River.

This study examined the age, growth, and maturation of 1,064 Coregonus ussuriensis individuals that were collected monthly from the middle section of the Amur River, China between 2016 and 2018. The fork length (FL) ranged from 14.9 to 49.1 cm for males and 21.5 to 58.8 cm for females, and the body weight (BW) ranged from 72.6 to 1,348.7 g for males and 107.9 to 2,854.9 g for females. The relationship of BW and FL was expressed as: BW♂ = 0.0324 × FL2.708; BW♀ = 0.014 × FL2.963. The sample ages ranged from 2 to 8 years for males and 2 to 9 years for females. We used the von Bertalanffy function based on otolith reading and observed FL data to simulate Coregonus ussuriensis growth, which has been suggested to be similar to that of other Salmonidae fishes. No significant difference in growth was determined between males and females. The monthly gonad somatic index (GSI) value ranged from 0.16% to 1.69% for males and from 0.73% to 16.15% for females, with a peak in November. Additionally, the reproductive staging suggested that the Coregonus ussuriensis spawning season was mainly in November and December. The size at maturity (FL50%) for males and females was 34.9 cm and 37.9 cm respectively, and the corresponding age (T50%) was 4.5 and 5.1, respectively. This study provides basic information for understanding the biological characteristics of Coregonus ussuriensis and should aid in the assessment and management of fishery resources.

Activation of TRPV4 stimulates transepithelial K+ secretion in rat epididymal epithelium.

The maturation of sperms is dependent on the coordinated interactions between sperm and the unique epididymal luminal milieu, which is characterized by high K+ content. This study investigated the involvement of transient receptor potential vanilloid 4 (TRPV4) in the K+ secretion of epididymal epithelium. The expression level and cellular localization of TRPV4 and Ca2+-activated K+ channels (KCa) were analyzed via RT-PCR, real-time quantitative PCR, western blot and immunofluorescence. The functional role of TRPV4 was investigated using short-circuit current (ISC) and intracellular Ca2+ imaging techniques. We found a predominant expression of TRPV4 in the corpus and cauda epididymal epithelium. Activation of TRPV4 with a selective agonist, GSK1016790A, stimulated a transient decrease in the ISC of the epididymal epithelium. The ISC response was abolished by either the TRPV4 antagonists, HC067047 and RN-1734, or the removal of basolateral K+. Simultaneously, the application of GSK1016790A triggered Ca2+ influx in epididymal epithelial cells. Our data also indicated that the big conductance KCa (BK), small conductance KCa (SK) and intermediate conductance KCa (IK) were all expressed in rat epididymis. Pharmacological studies revealed that BK, but not SK and IK, mediated TRPV4-elicited transepithelial K+ secretion. Finally, we demonstrated that TRPV4 and BK were localized in the epididymal epithelium, which showed an increased expression level from caput to cauda regions of rat epididymis. This study implicates that TRPV4 plays an important role in the formation of high K+ concentration in epididymal intraluminal fluid via promoting transepithelial K+ secretion mediated by BK.

Pulsatility damping in the microcirculation: Basic pattern and modulating factors.

Blood flow pulsatility is an important determinant of macro- and microvascular physiology. Pulsatility is damped largely in the microcirculation, but the characteristics of this damping and the factors that regulate it have not been fully elucidated yet. Applying computational approaches to real microvascular network geometry, we examined the pattern of pulsatility damping and the role of potential damping factors, including pulse frequency, vascular viscous resistance, vascular compliance, viscoelastic behavior of the vessel wall, and wave propagation and reflection. To this end, three full rat mesenteric vascular networks were reconstructed from intravital microscopic recordings, a one-dimensional (1D) model was used to reproduce pulsatile properties within the network, and potential damping factors were examined by sensitivity analysis. Results demonstrate that blood flow pulsatility is predominantly damped at the arteriolar side and remains at a low level at the venular side. Damping was sensitive to pulse frequency, vascular viscous resistance and vascular compliance, whereas viscoelasticity of the vessel wall or wave propagation and reflection contributed little to pulsatility damping. The present results contribute to our understanding of mechanical forces and their regulation in the microcirculation.