Prevalence and molecular characterization of hepatitis E virus (HEV) from wild rodents in Hubei Province, China.

Hepatitis E, caused by the hepatitis E virus (HEV), is a global public health issue. Low similarity between the gene sequences of mouse and human HEV led to the belief that the risk of human infection was low. Recent reports of chronic and acute hepatitis E caused by murine HEV infection in humans in Hong Kong have raised global concerns. Therefore, it is crucial to investigate the epidemiology and prevalence of HEV in China. We comprehensively analyzed different rodent HEV strains to understand rocahepevirus occurrence in Hubei Province, China. The HEV positivity rate for was 6.43% (73/1136). We identified seven near-full-length rocahepevirus strains and detected rat HEV antigens in tissues from different mouse species. HEV has extensive tissue tropism and a high viral load in the liver. We highlight the genetic diversity of HEVs in rodents and underscore the importance of paying attention to their variation and evolution.

SlCRCa is a key D-class gene controlling ovule fate determination in tomato.

Cell fate determination and primordium initiation on the placental surface are two key events for ovule formation in seed plants, which directly affect ovule density and seed yield. Despite ovules form in the marginal meristematic tissues of the carpels, angiosperm carpels evolved after the ovules. It is not clear how the development of the ovules and carpels is coordinated in angiosperms. In this study, we identify the S. lycopersicum CRABS CLAW (CRC) homologue SlCRCa as an essential determinant of ovule fate. We find that SlCRCa is not only expressed in the placental surface and ovule primordia but also functions as a D-class gene to block carpel fate and promote ovule fate in the placental surface. Loss of function of SlCRCa causes homeotic transformation of the ovules to carpels. In addition, we find low levels of the S. lycopersicum AINTEGUMENTA (ANT) homologue (SlANT2) favour the ovule initiation, whereas high levels of SlANT2 promote placental carpelization. SlCRCa forms heterodimer with tomato INNER NO OUTER (INO) and AGAMOUS (AG) orthologues, SlINO and TOMATO AGAMOUS1 (TAG1), to repress SlANT2 expression during the ovule initiation. Our study confirms that angiosperm basal ovule cells indeed retain certain carpel properties and provides mechanistic insights into the ovule initiation.

Preservative Effects of Curcumin on Semen of Hu Sheep.

Reactive oxygen species (ROS) are important factors that lead to a decline in sperm quality during semen preservation. Excessive ROS accumulation disrupts the balance of the antioxidant system in sperm and causes lipid oxidative damage, destroying its structure and function. Curcumin is a natural plant extract that neutralizes ROS and enhances the function of endogenous antioxidant enzymes. The effect of curcumin on the preservation of sheep semen has not been reported. This study aims to determine the effects of curcumin on refrigerated sperm (4 °C) and analyze the effects of curcumin on sperm metabolism from a Chinese native sheep (Hu sheep). The results showed that adding curcumin significantly improved (p < 0.05) the viability of refrigerated sperm at an optimal concentration of 20 µmol/L, and the plasma membrane and acrosome integrity in semen were significantly improved (p < 0.05). Adding curcumin to refrigerated semen significantly increased (p < 0.05) the levels of antioxidant enzymes (T-AOC, CAT, and SOD) and significantly decreased (p < 0.05) ROS production. A total of 13,796 metabolites in sperm and 20,581 metabolites in negative groups and curcumin-supplemented groups were identified using liquid chromatography-mass spectrometry. The proportion of lipids and lipid-like molecules among all metabolites in the sperm was the highest, regardless of treatment. We identified 50 differentially expressed metabolites (DEMs) in sperm between the negative control and curcumin-treated groups. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that DEMs were mainly enriched in the calcium signaling pathway, phospholipase D signaling pathway, sphingolipid metabolism, steroid hormone biosynthesis, 2-oxocarboxylic acid metabolism, and other metabolic pathways. The findings indicate that the addition of an appropriate concentration (20 µm/L) of curcumin to sheep semen can effectively suppress reactive oxygen species (ROS) production and extend the duration of cryopreservation (4 °C) by modulating the expression of sphingosine-1-phosphate, dehydroepiandrosterone sulfate, phytosphingosine, and other metabolites of semen. This discovery offers a novel approach to enhancing the cryogenic preservation of sheep semen.

Heat stress impairs floral meristem termination and fruit development by affecting the BR-SlCRCa cascade in tomato.

Floral meristem termination is a key step leading to carpel initiation and fruit development. The frequent occurrence of heat stress due to global warming often disrupts floral determinacy, resulting in defective fruit formation. However, the detailed mechanism behind this phenomenon is largely unknown. Here, we identify CRABS CLAW a (SlCRCa) as a key regulator of floral meristem termination in tomato. SlCRCa functions as an indispensable floral meristem terminator by suppressing SlWUS activity through the TOMATO AGAMOUS 1 (TAG1)-KNUCKLES (SlKNU)-INHIBITOR OF MERISTEM ACTIVITY (SlIMA) network. A direct binding assay revealed that SlCRCa specifically binds to the promoter and second intron of WUSCHEL (SlWUS). We also demonstrate that SlCRCa expression depends on brassinosteroid homeostasis in the floral meristem, which is repressed by heat stress via the circadian factor EARLY FLOWERING 3 (SlELF3). These results provide new insights into floral meristem termination and the heat stress response in flowers and fruits of tomato and suggest that SlCRCa provides a platform for multiple protein interactions that may epigenetically abrogate stem cell activity at the transition from floral meristem to carpel initiation.

MiR-188-5p regulates the proliferation and differentiation of goat skeletal muscle satellite cells by targeting calcium/calmodulin dependent protein kinase II beta.

OBJECTIVE: The aim of this study was to reveal the role and regulatory mechanism of miR-188-5p in the proliferation and differentiation of goat muscle satellite cells. METHODS: Goat skeletal muscle satellite cells isolated in the pre-laboratory were used as the test material. First, the expression of miR-188-5p in goat muscle tissues at different developmental stages was detected by quantitative reverse transcription polymerase chain reaction (qRT-PCR). In addition, miR-188-5p was transfected into goat skeletal muscle satellite cells by constructing mimics and inhibitors of miR-188-5p, respectively. The changes of differentiation marker gene expression were detected by qPCR method. RESULTS: It was highly expressed in adult goat latissimus dorsi and leg muscles, goat fetal skeletal muscle, and at the differentiation stage of muscle satellite cells. Overexpression and interference of miR-188-5p showed that miR-188-5p inhibited the proliferation and promoted the differentiation of goat muscle satellite cells. Target gene prediction and dual luciferase assays showed that miR-188-5p could target the 3'untranslated region of the calcium/calmodulin dependent protein kinase II beta (CAMK2B) gene and inhibit luciferase activity. Further functional studies revealed that CAMK2B promoted the proliferation and inhibited the differentiation of goat muscle satellite cells, whereas si-CAMK2B restored the function of miR-188-5p inhibitor. CONCLUSION: These results suggest that miR-188-5p inhibits the proliferation and promotes the differentiation of goat muscle satellite cells by targeting CAMK2B. This study will provide a theoretical reference for future studies on the molecular mechanisms of skeletal muscle development in goats.

Identification of novel anti-ZIKV drugs from viral-infection temporal gene expression profiles.

Zika virus (ZIKV) infections are typically asymptomatic but cause severe neurological complications (e.g. Guillain-Barré syndrome in adults, and microcephaly in newborns). There are currently no specific therapy or vaccine options available to prevent ZIKV infections. Temporal gene expression profiles of ZIKV-infected human brain microvascular endothelial cells (HBMECs) were used in this study to identify genes essential for viral replication. These genes were then used to identify novel anti-ZIKV agents and validated in publicly available data and functional wet-lab experiments. Here, we found that ZIKV effectively evaded activation of immune response-related genes and completely reprogrammed cellular transcriptional architectures. Knockdown of genes, which gradually upregulated during viral infection but showed distinct expression patterns between ZIKV- and mock infection, discovered novel proviral and antiviral factors. One-third of the 74 drugs found through signature-based drug repositioning and cross-reference with the Drug Gene Interaction Database (DGIdb) were known anti-ZIKV agents. In cellular assays, two promising antiviral candidates (Luminespib/NVP-AUY922, L-161982) were found to reduce viral replication without causing cell toxicity. Overall, our time-series transcriptome-based methods offer a novel and feasible strategy for antiviral drug discovery. Our strategies, which combine conventional and data-driven analysis, can be extended for other pathogens causing pandemics in the future.

Cold stress induces malformed tomato fruits by breaking the feedback loops of stem cell regulation in floral meristem.

Fruit malformation is a major constrain in fruit production worldwide resulting in substantial economic losses. The farmers for decades noticed that the chilling temperature before blooming often caused malformed fruits. However, the molecular mechanism underlying this phenomenon is unclear. Here we examined the fruit development in response to cold stress in tomato, and demonstrated that short-term cold stress increased the callose accumulation in both shoot apical and floral meristems, resulting in the symplastic isolation and altered intercellular movement of WUS. In contrast to the rapidly restored SlWUS transcription during the recovery from cold stress, the callose removal was delayed due to obstructed plasmodesmata. The delayed reinstatement of cell-to-cell transport of SlWUS prevented the activation of SlCLV3 and TAG1, causing the interrupted feedback inhibition of SlWUS expression, leading to the expanded stem cell population and malformed fruits. We further showed that the callose dynamics in response to short-term cold stress presumably exploits the mechanism of bud dormancy during the seasonal growth, involving two antagonistic hormones, abscisic acid and gibberellin. Our results provide a novel insight into the cold stress regulated malformation of fruit.

Antagonistic mechanisms of bisphenol analogues on the estrogen receptor α in zebrafish embryos: Experimental and computational studies.

Bisphenol A (BPA) can disturb the estrogen receptor α (ERα)-mediated signaling pathway, which results in endocrine-disrupting effects and reproductive toxicity. Most BPA analogues as alternatives were evidenced to generate estrogenic activity as agonists or partial agonists of ERα. Recent studies indicated that certain BPA analogues, such as bisphenol M (BPM), bisphenol P (BPP), and bisphenol FL (BPFL), exhibited strong anti-estrogenic effects comparable with the typical antagonist 4-hydroxytamoxifen. However, conflicting findings were also observed for the compounds in different in vitro assays, and whether these BPA analogues can elicit an in vivo effect on ERα at environmentally relevant concentrations remains unknown. The underlying structural basis of estrogenic/anti-estrogenic activity should be further elucidated at the atomic level. To address these issues, we combined zebrafish-based in vivo and in silico methods to assess the effects of the compounds on ERα. The results show that the expressions of ERα-mediated downstream related genes in zebrafish embryos decreased after exposed to the compounds. Further molecular dynamics simulations were used to probe the antagonistic mechanisms of the compounds on ERα. The key H-bonding interactions were identified as important ligand recognition by ERα in the analysis of binding modes and binding free energy calculations. In summary, the current study provides preliminary in vivo evidence of fish species for the anti-estrogenic activity of certain BPA analogues.

Research on prognostic risk assessment model for acute ischemic stroke based on imaging and multidimensional data.

Accurately assessing the prognostic outcomes of patients with acute ischemic stroke and adjusting treatment plans in a timely manner for those with poor prognosis is crucial for intervening in modifiable risk factors. However, there is still controversy regarding the correlation between imaging-based predictions of complications in acute ischemic stroke. To address this, we developed a cross-modal attention module for integrating multidimensional data, including clinical information, imaging features, treatment plans, prognosis, and complications, to achieve complementary advantages. The fused features preserve magnetic resonance imaging (MRI) characteristics while supplementing clinical relevant information, providing a more comprehensive and informative basis for clinical diagnosis and treatment. The proposed framework based on multidimensional data for activity of daily living (ADL) scoring in patients with acute ischemic stroke demonstrates higher accuracy compared to other state-of-the-art network models, and ablation experiments confirm the effectiveness of each module in the framework.

Analysis of lncRNA in the skeletal muscle of rabbits at different developmental stages.

It is universally acknowledged that lncRNA plays an important role in the regulation of animal skeletal muscle development regulation. However, there is a lack of relevant research on lncRNA in rabbit skeletal muscle development. Thus, we explored the expression profiles of lncRNA in rabbits at three growth stages (2-week-old fetus, 6-week-old post-weaning, and 6-month-old adult) using RNA-seq. A total of 554 differentially expressed lncRNAs (235 up- and 319 down-regulated) were found between the post-weaning and fetus groups and 19 (7 up- and 12 down-regulated) between the post-weaning and adult groups and 429 (115 up- and 314 down-regulated) between the fetus and adult. The enrichment pathways in the post-weaning and fetus groups were mainly concentrated at AMPK and PI3K-Akt signaling pathways, and the co-expression results revealed that LINC-2903, LINC-2374, LINC-8591 plays a role in early maintenance of skeletal muscle development. The enriched pathways in the fetus and adult groups were mainly involved in PI3K-Akt signaling pathways with a strong association found in mTOR signaling pathways. Analysis of the co-expression results suggests that LINC-5617 may be involved in the proliferation of embryonic skeletal muscle cells, and that LINC-8613 and LINC-8705 may provide energy for postnatal skeletal muscle development. The specific roles of different lncRNAs in different developmental stages of New Zealand White rabbits obtained. This will contribute to the subsequent study on the regulatory mechanism of muscle development in New Zealand White rabbits.

LeGO-LOAM-SC: An Improved Simultaneous Localization and Mapping Method Fusing LeGO-LOAM and Scan Context for Underground Coalmine.

Simultaneous localization and mapping (SLAM) is one of the key technologies for coal mine underground operation vehicles to build complex environment maps and positioning and to realize unmanned and autonomous operation. Many domestic and foreign scholars have studied many SLAM algorithms, but the mapping accuracy and real-time performance still need to be further improved. This paper presents a SLAM algorithm integrating scan context and Light weight and Ground-Optimized LiDAR Odometry and Mapping (LeGO-LOAM), LeGO-LOAM-SC. The algorithm uses the global descriptor extracted by scan context for loop detection, adds pose constraints to Georgia Tech Smoothing and Mapping (GTSAM) by Iterative Closest Points (ICP) for graph optimization, and constructs point cloud map and an output estimated pose of the mobile vehicle. The test with KITTI dataset 00 sequence data and the actual test in 2-storey underground parking lots are carried out. The results show that the proposed improved algorithm makes up for the drift of the point cloud map, has a higher mapping accuracy, a better real-time performance, a lower resource occupancy, a higher coincidence between trajectory estimation and real trajectory, smoother loop, and 6% reduction in CPU occupancy, the mean square errors of absolute trajectory error (ATE) and relative pose error (RPE) are reduced by 55.7% and 50.3% respectively; the translation and rotation accuracy are improved by about 5%, and the time consumption is reduced by 2~4%. Accurate map construction and low drift pose estimation can be performed.

Single-step synthesis of layered double hydroxides ultrathin nanosheets.

A novel single-step approach was developed to prepare large-scale MgAl-LDHs ultrathin nanosheets. The key point of the successful realization was that we employed a high concentration of H(2)O(2). Oxygen molecules, derived from in situ decomposition of H(2)O(2), were speculated to be the decisive factor leading to complete separation of LDHs layers. The ultrathin nanosheets were characterized by XRD, TEM, AFM, FT-IR, and TG-DSC. The results indicated that the thickness of these nanosheets was about 1.44 nm, which was almost in perfect agreement with the theoretical thickness of two LDHs layers. From the TG-DSC curves, the weight loss of these exfoliated MgAl-LDHs ultrathin nanosheets at 500°C was 18.5%, which was much smaller compared to the 32.3% weight loss of unexfoliated MgAl-LDHs.

Two different electron transfer pathways may involve in azoreduction in Shewanella decolorationis S12.

Electron transfer pathways for azoreduction by S. decolorationis S12 were studied using a mutant S12-22 which had a transposon insertion in ccmA. The results imply that there are two different pathways for electron transport to azo bonds. The colony of S12-22 was whitish and incapable of producing mature c-type cytochromes whose alpha-peak was at 553 nm in the wild type S12. The mutant S12-22 could not use formate as the sole electron donor for azoreduction either in vivo or in vitro, but intact cells of S12-22 were able to reduce azo dyes of low polarity, such as methyl red, when NADH was served as the sole electron donor. Although the highly polar-sulfonated amaranth could not be reduced by intact cells of S12-22, it could be efficiently reduced by cell extracts of the mutant when NADH was provided as the sole electron donor. These results suggest that the mature c-type cytochromes are essential electron mediators for the extracellular azoreduction of intact cells, while the other pathway without the involvement of mature c-type cytochromes, NADH-dependent oxidoreductase-mediated electron transfer pathway can reduce lowly polar sulfonated azo dyes inside the whole cells or highly polar sulfonated azo dyes in the cell extracts without bacterial membrane barriers.

[Study of effect and mechanism of midbrain periaqueductal gray NO on development of hypertension in stressed rats].

AIM: To study the role of NO in the midbrain periaqueductal gray (PAG) in the development of stress-induced hypertension (SIH). METHODS: The model of stress-induced hypertension (SIH) rat was established by electric-foot in company with noise, NADPH-d histochemistry technique was used to investigate the change of nitric oxide synthase (NOS) positive neurons. Selecting and using microinjection and radioimmunoassay, we studied the effects of blood pressure and the content of Ach in rostral ventrolateral medulla (RVLM) after microinjection of L-NNA into PAG. RESULTS: (1) The blood pressure increased, the cell number decreased and the grey degree value increased for the NOS positive neurons of PAG dorsolateral subdivision in SIH rats, and the content of Ach increased in RVLM. (2) Following microinjection of 100 mmol/L 0.1 microl L-NNA into PAG, the mean arterial pressure (MAP) and the content of Ach in RVLM increased in control rats, whereas the change of MAP was significantly smaller in SIH rats than control. CONCLUSION: The plastic change of NOS positive neurons of PAG in SIH rats may be involved in the development of SIH, which may be mediated by Ach in RVLM.

Modulation by oxytocin of ATP-activated currents in rat dorsal root ganglion neurons.

The modulatory effect of oxytocin (OT) on ATP-activated currents (I(ATP)) was studied in freshly isolated dorsal root ganglion (DRG) neurons of rats using whole cell clamp technique. In most of the neurons examined (50/70, 71.4%) extracellular application of OT (10(-9)-10(-5) mol/L) suppressed I(ATP) while in the rest (20/70, 28.6%) no modulatory effect was observed. OT shifted the ATP concentration-response curve downwards with a decrease of 39.8+/-4.2% in the maximal current response and with no significant change of Kd value. This OT-induced inhibition of I(ATP) showed no voltage dependence, and could be blocked by [d(CH(2))(5),Tyr(Me)(2),Thr(4),Tyr-NH(2)(9)]-OVT (d(CH(2))(5)-OVT) (10(-8) mol/L), a specific OT receptor antagonist. Intracellular application of H-9 (4 x 10(-5) mol/L, an inhibitor of protein kinase A) (n=12), BAPTA (10(-2) mol/L, a chelator of calcium ions) (n=4) could reverse the inhibitory effect of extracellular OT (10(-7) mol), while inclusion of H-7 (2 x 10(-5) mol/L, a protein kinase C inhibitior) (n=8) and KN-93 (10(-5) mol/L, an inhibitor of CaMKII) (n=9) in the recording pipette did not affect this effect. The results suggested that OT inhibition on ATP-activated currents was mediated by OT receptors in the membrane of DRG neurons; and this inhibitory effect involved the transduction of intracellular cAMP-PKA and Ca(2+).

[Intracellular dialysis with a microcatheter inserted into the patch-clamp pipette].

In this paper we present an easily available method of intracellular dialysis via a microcatheter inserted into glass pipette during patch clamp experiment. An oblique hole through the glass pipette holder (above the lateral hole for cell-seal suction) is drilled, through which a microcatheter (O.D.=0.1 mm) made from the universal pipetter tip by hand-drawing passes and sticks out of the holder mouth in parallel with the Ag-AgCl electrode. With a syringe connected to the microcatheter, substitution of intracellular solution and intracellular dialysis of drugs can be achieved easily. Compared with repatch technique and intracellular solution substitution techniques used abroad, this method operates more easily and can produce more reliable results.