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The central histaminergic system has a pivotal role in emotional regulation and psychiatric disorders, including anxiety, depression and schizophrenia. However, the effect of histamine on neuronal activity of the centrolateral amygdala (CeL), an essential node for fear and anxiety processing, remains unknown. Here, using immunostaining and whole-cell patch clamp recording combined with optogenetic manipulation of histaminergic terminals in CeL slices prepared from histidine decarboxylase (HDC)-Cre rats, we show that histamine selectively suppresses excitatory synaptic transmissions, including glutamatergic transmission from the basolateral amygdala, on both PKC-δ- and SOM-positive CeL neurons. The histamine-induced effect is mediated by H3 receptors expressed on VGLUT1-/VGLUT2-positive presynaptic terminals in CeL. Furthermore, optoactivation of histaminergic afferent terminals from the hypothalamic tuberomammillary nucleus (TMN) also significantly suppresses glutamatergic transmissions in CeL via H3 receptors. Histamine neither modulates inhibitory synaptic transmission by presynaptic H3 receptors nor directly excites CeL neurons by postsynaptic H1, H2 or H4 receptors. These results suggest that histaminergic afferent inputs and presynaptic H3 heteroreceptors may hold a critical position in balancing excitatory and inhibitory synaptic transmissions in CeL by selective modulation of glutamatergic drive, which may not only account for the pathophysiology of psychiatric disorders but also provide potential psychotherapeutic targets. KEY POINTS: Histamine selectively suppresses the excitatory, rather than inhibitory, synaptic transmissions on both PKC-δ- and SOM-positive neurons in the centrolateral amygdala (CeL). H3 receptors expressed on VGLUT1- or VGLUT2-positive afferent terminals mediate the suppression of histamine on glutamatergic synaptic transmission in CeL. Optogenetic activation of hypothalamic tuberomammillary nucleus (TMN)-CeL histaminergic projections inhibits glutamatergic transmission in CeL via H3 receptors.
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Renal transplantation is the preferred treatment option for patients with end-stage renal disease (ESRD) in a clinical setting. Antibody mediated rejection (AMR) is one of the leading causes of graft dysfunction. To address the current shortcomings in the early diagnosis and treatment of AMR in clinical practice, this article analyzes the distribution of different circulating T follicular helper (cTfh) cell subtypes and B cell subpopulations in peripheral blood and detects the cytokine levels of chemokine ligand 13 (CXCL13), interleukin-21 (IL-21), and interleukin-4 (IL-4) related to cTfh cells in peripheral blood of kidney transplant recipients. Moreover, we also explore the correlation between cTfh cells, peripheral blood memory B cells, and AMR, their value as early predictive indicators of AMR, and explore potential therapeutic targets for AMR patients. Our results indicate that the proportion of cTfh cells increased at the onset of AMR, which plays an important role in antigen-specific B-cell immune regulation. Activation of cTfh cells in AMR patients correlates with phenotypes of memory B cells and plasma blasts. cTfh cells and memory B cells have promising diagnostic efficacies and predictive values for AMR. The proportion of cTfh cells to CD4+ T cells and the proportion of memory B cells to CD19+ B cells are correlated with serum creatinine levels, indicating that cTfh cells and memory B cells may be involved in the progression of AMR. In addition, the CXCL13, IL-21, and IL-4, which were associated with cTfh cells, may be involved in the onset of AMR.
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BACKGROUND: Spinal cord injury (SCI) is a debilitating illness in humans that causes permanent loss of movement or sensation. To treat SCI, exosomes, with their unique benefits, can circumvent limitations through direct stem cell transplantation. Therefore, we utilized Gelfoam encapsulated with exosomes derived from human umbilical cord mesenchymal stem cells (HucMSC-EX) in a rat SCI model. METHODS: SCI model was established through hemisection surgery in T9 spinal cord of female Sprague-Dawley rats. Exosome-loaded Gelfoam was implanted into the lesion site. An in vivo uptake assay using labeled exosomes was conducted on day 3 post-implantation. Locomotor functions and gait analyses were assessed using Basso-Beattie-Bresnahan (BBB) locomotor rating scale and DigiGait Imaging System from weeks 1 to 8. Nociceptive responses were evaluated through von Frey filament and noxious radiant heat tests. The therapeutic effects and potential mechanisms were analyzed using Western blotting and immunofluorescence staining at week 8 post-SCI. RESULTS: For the in vivo exosome uptake assay, we observed the uptake of labeled exosomes by NeuN+, Iba1+, GFAP+, and OLIG2+ cells around the injured area. Exosome treatment consistently increased the BBB score from 1 to 8 weeks compared with the Gelfoam-saline and SCI control groups. Additionally, exosome treatment significantly improved gait abnormalities including right-to-left hind paw contact area ratio, stance/stride, stride length, stride frequency, and swing duration, validating motor function recovery. Immunostaining and Western blotting revealed high expression of NF200, MBP, GAP43, synaptophysin, and PSD95 in exosome treatment group, indicating the promotion of nerve regeneration, remyelination, and synapse formation. Interestingly, exosome treatment reduced SCI-induced upregulation of GFAP and CSPG. Furthermore, levels of Bax, p75NTR, Iba1, and iNOS were reduced around the injured area, suggesting anti-inflammatory and anti-apoptotic effects. Moreover, exosome treatment alleviated SCI-induced pain behaviors and reduced pain-associated proteins (BDNF, TRPV1, and Cav3.2). Exosomal miRNA analysis revealed several promising therapeutic miRNAs. The cell culture study also confirmed the neurotrophic effect of HucMSCs-EX. CONCLUSION: Implantation of HucMSCs-EX-encapsulated Gelfoam improves SCI-induced motor dysfunction and neuropathic pain, possibly through its capabilities in nerve regeneration, remyelination, anti-inflammation, and anti-apoptosis. Overall, exosomes could serve as a promising therapeutic alternative for SCI treatment.
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Modelos Animales de Enfermedad , Exosomas , Células Madre Mesenquimatosas , Neuralgia , Ratas Sprague-Dawley , Traumatismos de la Médula Espinal , Animales , Traumatismos de la Médula Espinal/terapia , Exosomas/metabolismo , Neuralgia/terapia , Neuralgia/metabolismo , Ratas , Femenino , Humanos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Locomoción , Esponja de Gelatina Absorbible , Cordón Umbilical/citologíaRESUMEN
The occurrence of multiple primary malignancies in a single patient has been relatively rare. We report here the case of a 71-year-old man with three primary tumors of lung cancer, intrahepatic cholangiocarcinoma, and prostate cancer, and a preliminary study of the mechanisms by which multiple primary tumors develop at the genetic level. Because of the late stage of the patient's condition, large tumor burden, and poor physical status, the patient survived only a few months. In the case presented herein, cholangiocarcinoma, lung cancer, and prostate cancer were found simultaneously, and the pathogenic sites are not related. Whole-exome sequencing was performed on the pathological tissues to explore the mechanism that may underlie multiple primary cancers at the genetic level. Several gene mutations were found in this case. They involved cell proliferation, cell cycle regulation, genetic stability, metabolism, cell invasion, angiogenesis, cell apoptosis, and other pathways. It can be preliminarily inferred that the mechanism underlying multiple primary tumors is related to the abnormality of tumor-promoting and suppressing pathways.
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Physical exercise is known to reduce anxiety, but the underlying brain mechanisms remain unclear. Here, we explore a hypothalamo-cerebello-amygdalar circuit that may mediate motor-dependent alleviation of anxiety. This three-neuron loop, in which the cerebellar dentate nucleus takes center stage, bridges the motor system with the emotional system. Subjecting animals to a constant rotarod engages glutamatergic cerebellar dentate neurons that drive PKCδ+ amygdalar neurons to elicit an anxiolytic effect. Moreover, challenging animals on an accelerated rather than a constant rotarod engages hypothalamic neurons that provide a superimposed anxiolytic effect via an orexinergic projection to the dentate neurons that activate the amygdala. Our findings reveal a cerebello-limbic pathway that may contribute to motor-triggered alleviation of anxiety and that may be optimally exploited during challenging physical exercise.
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Ansiolíticos , Animales , Ansiedad/metabolismo , Hipotálamo , Cerebelo , Trastornos de AnsiedadRESUMEN
Homeostasis is essential for muscle repair and regeneration after skeletal muscle exercise. This study investigated the role of methyltransferase-like 21C (METTL21C) in skeletal muscle of mice after exercise and the potential mechanism. First, muscle samples were collected at 2, 4 and 6 weeks after exercise, and liver glycogen, muscle glycogen, blood lactic acid and triglyceride were assessed. Moreover, the expression levels of autophagy markers and METTL21C in skeletal muscle were analyzed. The results showed that the expression levels of METTL21C and MYH7 in the gastrocnemius muscle of mice in the exercise group were significantly higher after exercise than those in the control group, which suggested that long-term exercise promoted the formation of slow-twitch muscle fibers in mouse skeletal muscle. Likewise, the autophagy capacity was enhanced with the prolongation of exercise in muscles. The findings were confirmed in mouse C2C12 cells. We discovered that knockdown of Mettl21c reduced the expression of MYH7 and the autophagy level in mouse myoblasts. These findings indicate that METTL21C promotes skeletal muscle homeostasis after exercise by enhancing autophagy, and also contributes to myogenic differentiation and the formation of slow muscle fibers.
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Autofagia , Metiltransferasas , Fibras Musculares de Contracción Lenta , Cadenas Pesadas de Miosina , Condicionamiento Físico Animal , Animales , Ratones , Línea Celular , Metiltransferasas/metabolismo , Metiltransferasas/genética , Ratones Endogámicos C57BL , Desarrollo de Músculos , Fibras Musculares de Contracción Lenta/metabolismo , Músculo Esquelético/metabolismo , Mioblastos/metabolismo , Cadenas Pesadas de Miosina/metabolismo , Cadenas Pesadas de Miosina/genéticaRESUMEN
Malignant ventricular arrhythmia (VA) after myocardial infarction (MI) is mainly caused by myocardial electrophysiological remodeling. Brahma-related gene 1 (BRG1) is an ATPase catalytic subunit that belongs to a family of chromatin remodeling complexes called Switch/Sucrose Non-Fermentable Chromatin (SWI/SNF). BRG1 has been reported as a molecular chaperone, interacting with various transcription factors or proteins to regulate transcription in cardiac diseases. In this study, we investigated the potential role of BRG1 in ion channel remodeling and VA after ischemic infarction. Myocardial infarction (MI) mice were established by ligating the left anterior descending (LAD) coronary artery, and electrocardiogram (ECG) was monitored. Epicardial conduction of MI mouse heart was characterized in Langendorff-perfused hearts using epicardial optical voltage mapping. Patch-clamping analysis was conducted in single ventricular cardiomyocytes isolated from the mice. We showed that BRG1 expression in the border zone was progressively increased in the first week following MI. Cardiac-specific deletion of BRG1 by tail vein injection of AAV9-BRG1-shRNA significantly ameliorated susceptibility to electrical-induced VA and shortened QTc intervals in MI mice. BRG1 knockdown significantly enhanced conduction velocity (CV) and reversed the prolonged action potential duration in MI mouse heart. Moreover, BRG1 knockdown improved the decreased densities of Na+ current (INa) and transient outward potassium current (Ito), as well as the expression of Nav1.5 and Kv4.3 in the border zone of MI mouse hearts and in hypoxia-treated neonatal mouse ventricular cardiomyocytes. We revealed that MI increased the binding among BRG1, T-cell factor 4 (TCF4) and ß-catenin, forming a transcription complex, which suppressed the transcription activity of SCN5A and KCND3, thereby influencing the incidence of VA post-MI.
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Infarto del Miocardio , Ratones , Animales , Infarto del Miocardio/metabolismo , Arritmias Cardíacas/genética , Miocardio/patología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Miocitos Cardíacos/metabolismoRESUMEN
The five core indicators(the case mix index, the proportion of level-4 surgery, the proportion of technical service income in medical income, the proportion of personnel expenditure in business expenditure, and the proportion of fixed part in personnel salary) and target values determined by the pilot goal of high-quality development of high-level public hospitals jointly built by National Health Commission and Provincial Government had become the core indicators for evaluating the quality and efficiency of public hospital development. The authors proposed the optimization and improvement measures for the five core indicators one by one from the internal reform and innovation in hospitals, as well as the synergetic development and governance of " insurance-medical-medicine linkage", combined with the current situation of a pilot hospital. The authors also proposed the starting points and driving force for promoting the high-quality development of public hospitals through the synergetic development and governance of " insurance-medical-medicine linkage", including implementing government investment responsibilities, streamlining the price evaluation of medical services, deepening the reform of medical insurance payment, accelerating the expansion of drug and consumable procurement, and promoting the application of advanced technologies and products, in order to provide reference for the in-depth promotion of high-quality development of public hospitals.
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Objective To investigate the clonal rearrangement characteristics and clinical application value of IGH gene in B-cell non-Hodgkin’s lymphoma (B-NHL). Methods Demographic and clinical data as well as IGH sequencing results of 55 patients with B-NHL who underwent next-generation sequencing (NGS) testing were collected, and IGH gene clonal rearrangement was detected. The characteristics of IGH gene clonal rearrangement, IGHV gene usage, and the clinical application value of NGS for IGH clonal rearrangement were analyzed. Results Among 55 patients with B-NHL and IGH clonal rearrangement, single dominant clones were mainly detected (85.45%, 47/55); a few patients had two (12.73%, 7/55) and three dominant clones (1.82%, 1/55). In terms of preference for IGHV gene usage, IGHV3 gene had the highest frequency of access in B-NHL, followed by IGHV4. Among the IGHV subtypes, IGHV3-23 had the highest frequency in chronic lymphocytic leukemia/small lymphocytic lymphoma, and IGHV4-34 had the highest frequency in primary central nervous system diffuse large B-cell lymphoma and not otherwise specified diffuse large B-cell lymphoma. Conclusion A preference for IGHV gene usage in clonal rearrangement of IGH genes is noted in B-NHL patients with different pathological types. Using NGS to detect IGH clonal rearrangement can identify subclones and clonal correlations, and assist in disease diagnosis.
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Professor Lau Wanyee, a member of the Chinese Academy of Sciences and a pro-fessor at the Chinese University of Hong Kong, actively advocates conducting clinical researches through "planting fruit trees" and "growing orchards", aiming to cultivate a team of dual-skilled talents in clinical practice and research, effectively improve the scientific and technological level of clinical medicine in China, make voice heard in the international medical science field, and better serve human health. He organized a clinical research training course in scholars′ forum for Hepatobiliary Young Expert Working Group of Chinese College of Surgeons. Throughout three sessions of the training course, a distinct theme was focused on how to enhance the level of clinical research in China and make voice heard by the international scholars. A group of multi-dimensional experts were gathered, including experts from surgery, methodology, and management, as well as both renowned experts and young talents. A lively teaching model was adopted, combining guided presentations with interactive discussion and debate sessions. A clean and upright academic spirit was strongly advocated, in which international rules were adopted to conduct in-depth analysis and sharp criticism of seven proposed clinical research projects and four published papers with high international influence to find quarrel in a straw. This clinical research training course provides a new model of guidance for young physicians in conducting clinical research. As a result, all attendees felt deeply educated and benefited greatly from the training session. This training activity not only laid a solid foundation for the development of scientization, standardization, and internationali-zation of clinical research in digestive surgery in China, but also demonstrated a correct path for cultivating a group of young and middle-aged clinical medical scientists with scientific spirit.
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Surgical treatment is the primary curative approach for hepatocellular carcinoma (HCC). In China, the proportion of advanced HCC is high, with a low rate of surgical removal at initial diagnosis and a high rate of postoperative recurrence, posing a serious threat to public health. With the advent of new therapeutic drugs and updated treatment concepts, the comprehensive treatment of HCC has entered a new era. Systemic treatments represented by targeted therapy and immuno-therapy, non-surgical local treatments such as interventional and radiotherapy, and the combination of systemic and local treatments, have significantly improved the treatment efficacy, bringing hope to patients. The authors review past studies, summarize diagnostic and treatment experience, and discuss the comprehensive treatment strategy for HCC in the era of targeted and immunotherapy, with surgery as the main approach.
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The growth of three plague phages from Qinghai Plateau in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,PTB5,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were detected through a micromethod based on the OmniLogTM microbial identification system and by the drop method,to provide a scientific basis for future ecological studies and classification based on the host range.For plague vaccine strains EV76 and 614F,successful phage infection and subsequent phage growth were observed in the host bacte-rium.Diminished bacterial growth and respiration and a concomitant decrease in color were observed with the OmniLogTM mi-crobial identification system at 33 ℃ for 48 h.Yersinia pseudotuberculosis PTB5 was sensitive to Yersinia pestis phage 476,but Yersinia pseudotuberculosis PST5 was insensitive to phage 087 and 072204.Three strains of non-Yersinia pestis(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersinia enterocolitica 52302-2)were insensitive to Yersinia pestis pha-ges 087,072204,and 476 showed similar growth curves.The growth of phages 476 and 087,as determined with the drop method,in two Yersinia pestis strains(plague vaccine strains EV76 and 614F)and four non-Yersinia pestis strains(Yersinia pseudotuberculosis PTB3,Escherichia coli V517,and Yersin-ia enterocolitica 52302-2)showed the same results at 37 ℃,on the basis of comparisons with the OmniLogTM microbial i-dentification system;in contrast,phages 072204 did not show plaques on solid medium at 37 ℃ with plague vaccine strains EV76 and 614F.Determination based on the OmniLogTM detection system can be used as an alternative to the traditional determination of the host range,thus providing favorable application val-ue for determining the interaction between the phage and host bacteria.
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OBJECTIVE To study the effects of Phellodendron amurense polysaccharides (PAP) on improving gouty nephropathy (GN) in rats, and to investigate its mechanism primarily by interfering the p38 mitogen-activated protein kinase (p38 MAPK)/nuclear factor-κB(NF-κB)/tumor necrosis factor-α(TNF-α). METHODS Sixty rats were randomly divided into normal group (water), model group (water), allopurinol group (positive control, 20 mg/kg), PAP high-dose, medium-dose and low-dose groups (100, 50, 25 mg/kg, by raw material) after being stratified by body weight, with 10 rats in each group. Except for the normal group, the other groups were induced to construct GN model by giving 1 500 mg/kg potassium oxazinate and 100 mg/kg adenine intragastrically for 14 days. After modeling, the rats in each group were given relevant medicine/water intragastrically, once a day, for consecutive 28 days. After the last medication, the levels of biochemical parameters related to renal function [uric acid, creatinine (Cr), blood urea nitrogen (BUN), xanthine oxidase (XOD)] were detected in rats, and the histopathological changes in the rat kidney were observed. The protein expressions of monocyte chemoattractant protein-1(MCP-1),TNF-α and interleukin-6(IL-6) as well as the phosphorylation levels of p38 MAPK and NF-κB p65 protein were determined in renal tissue of rats. RESULTS Compared with the normal group, the model group suffered from the dilatation of renal tubules, structural damage to glomeruli, accompanied by inflammatory infiltration and fibrosis; the contents of uric acid, Cr, BUN and XOD, the protein expressions of MCP-1,TNF-α and IL-6 and the phosphorylation levels of p38 MAPK and NF-κB p65 protein were all increased significantly (P<0.05 or P<0.01). Compared with the model group, the pathological symptoms of renal tissue in rats had been improved to varying degrees in different dose groups of PAP; the contents of uric acid, Cr, BUN and XOD, protein expressions of MCP-1, TNF-α and IL-6, the phosphorylation levels of p38 MAPK and NF-κB p65 protein in PAP high-dose and PAP medium-dose groups were all decreased significantly (P<0.05 or P<0.01). CONCLUSIONS PAP exhibits an anti-GN effect, the mechanism of which may be associated with inhibiting the p38 MAPK/NF-κB/TNF-α signaling pathway.
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Sewage sludge (SS) is an environmental issue due to its high organic content and ability to release hazardous substances. Most of the treatments available are biological, thermal hydrolysis, mechanical (ultrasound, high pressure, and lysis), chemical with oxidation (mainly ozonation), and alkali pre-treatments. Other treatment methods include landfill, wet oxidation, composting, drying, stabilization, incineration, pyrolysis, carbonization, liquefaction, gasification, and torrefaction. Some of these SS disposal methods damage the ecosystem and underutilize the potential resource value of SS. These challenges must be overcome with an innovative technique for the improvement of SS's nutritional value, energy content, and usability. This review proposes plasma pyrolysis and anaerobic digestion (AD) as promising SS treatment technologies. Plasma pyrolysis pre-treats SS to make it digestible by AD bacteria and immobilizes the heavy metals. The addition of Char to the upstream AD process increases the quantity and quality of biogas produced while enhancing the nutrients in the digestate. These two processes are integrated at high temperatures, thus creating concerns about their energy demand. These challenges are offset by the generated energy that can run the treatment plant or be sold to the grid, generating additional cash. Plasma pyrolysis wastes can also be converted into biochar, organic fertilizer, or soil conditioner. These combined technologies' financial sustainability depends on the treatment facility's circumstances and location. Plasma pyrolysis and AD can treat SS sustainably and provide nutrients and resources. This paper explains the co-process treatment route's techno-economic prospects, challenges, and recommendations for the future application of SS valorization and resource recovery.
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BACKGROUND: Full-cohort and sibling-comparison designs have yielded inconsistent results about the impacts of caesarean delivery on offspring health outcomes, with the effect estimates from the latter being more likely directed towards the null value. We hypothesized that the seemingly conservative results obtained from the sibling-comparison design might be attributed to inadequate adjustment for non-shared confounders between siblings, particularly maternal age at delivery. METHODS: A systematic review and meta-analysis was first conducted. PubMed, Embase, and the Web of Science were searched from database inception to April 6, 2022. Included studies (1) examined the association of caesarean delivery, whether elective or emergency, with offspring health outcomes; (2) simultaneously conducted full-cohort and sibling-comparison analyses; and (3) reported adjusted effect estimates with 95% confidence intervals (95% CIs). No language restrictions were applied. Data were extracted by 2 reviewers independently. Three-level meta-analytic models were used to calculate the pooled odds ratios (ORs) and 95% CIs for caesarean versus vaginal delivery on multiple offspring health outcomes separately for full-cohort and sibling-comparison designs. Subgroup analyses were performed based on the method of adjustment for maternal age at delivery. A simulation study was then conducted. The simulated datasets were generated with some key parameters derived from the meta-analysis. RESULTS: Eighteen studies involving 21,854,828 individuals were included. The outcomes assessed included mental and behavioral disorders; endocrine, nutritional and metabolic diseases; asthma; cardiorespiratory fitness; and multiple sclerosis. The overall pooled OR for estimates from the full-cohort design was 1.14 (95% CI: 1.11 to 1.17), higher than that for estimates from the sibling-comparison design (OR = 1.08; 95% CI: 1.02 to 1.14). Stratified analyses showed that estimates from the sibling-comparison design varied considerably across studies using different methods to adjust for maternal age at delivery in multivariate analyses, while those from the full-cohort design were rather stable: in studies that did not adjust maternal age at delivery, the pooled OR of full-cohort vs. sibling-comparison design was 1.10 (95% CI: 0.99 to 1.22) vs. 1.06 (95% CI: 0.85 to 1.31), in studies adjusting it as a categorical variable, 1.15 (95% CI: 1.11 to 1.19) vs. 1.07 (95% CI: 1.00 to 1.15), and in studies adjusting it as a continuous variable, 1.12 (95% CI: 1.05 to 1.19) vs. 1.12 (95% CI: 0.98 to 1.29). The severe underestimation bias related to the inadequate adjustment of maternal age at delivery in sibling-comparison analyses was fully replicated in the simulation study. CONCLUSIONS: Sibling-comparison analyses may underestimate the association of caesarean delivery with multiple offspring health outcomes due to inadequate adjustment of non-shared confounders, such as maternal age at delivery. Thus, we should be cautious when interpreting the seemingly conservative results of sibling-comparison analyses in delivery-related studies.
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Asma , Hermanos , Femenino , Embarazo , Humanos , Cesárea , Parto Obstétrico , Evaluación de Resultado en la Atención de SaludRESUMEN
Human pluripotent stem cells (human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs)) have unlimited proliferative potential, whereas adult stem cells such as bone marrow-derived stem cells and adipose-derived stem cells have problems with aging. When hPSCs are intended to be cultured on feeder-free or xeno-free conditions without utilizing mouse embryonic fibroblasts or human fibroblasts, they cannot be cultured on conventional tissue culture polystyrene dishes, as adult stem cells can be cultured but should be cultivated on material surfaces grafted or coated with (a) natural or recombinant extracellular matrix (ECM) proteins, (b) ECM protein-derived peptides and specific synthetic polymer surfaces in xeno-free and/or chemically defined conditions. This review describes current developing cell culture biomaterials for the proliferation of hPSCs while maintaining the pluripotency and differentiation potential of the cells into 3 germ layers. Biomaterials for the cultivation of hPSCs without utilizing a feeder layer are essential to decrease the risk of xenogenic molecules, which contributes to the potential clinical usage of hPSCs. ECM proteins such as human recombinant vitronectin, laminin-511 and laminin-521 have been utilized instead of Matrigel for the feeder-free cultivation of hPSCs. The following biomaterials are also discussed for hPSC cultivation: (a) decellularized ECM, (b) peptide-grafted biomaterials derived from ECM proteins, (c) recombinant E-cadherin-coated surface, (d) polysaccharide-immobilized surface, (e) synthetic polymer surfaces with and without bioactive sites, (f) thermoresponsive polymer surfaces with and without bioactive sites, and (g) synthetic microfibrous scaffolds.
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Células Madre Adultas , Laminina , Animales , Ratones , Adulto , Humanos , Laminina/farmacología , Fibroblastos , Materiales Biocompatibles/farmacología , Proliferación CelularRESUMEN
BACKGROUND: Hydrogen sulfide (H2S) is a recently discovered gaseous neurotransmitter in the nervous and gastrointestinal systems. It exerts its effects through multiple signaling pathways, impacting various physiological activities. The nucleus tractus solitarius (NTS), a vital nucleus involved in visceral sensation, was investigated in this study to understand the role of H2S in regulating gastric function in rats. AIM: To examine whether H2S affects the nuclear factor kappa-B (NF-κB) and transient receptor potential vanilloid 1 pathways and the neurokinin 1 (NK1) receptor in the NTS. METHODS: Immunohistochemical and fluorescent double-labeling techniques were employed to identify cystathionine beta-synthase (CBS) and c-Fos co-expressed positive neurons in the NTS during rat stress. Gastric motility curves were recorded by inserting a pressure-sensing balloon into the pylorus through the stomach fundus. Changes in gastric motility were observed before and after injecting different doses of NaHS (4 nmol and 8 nmol), physiological saline, Capsazepine (4 nmol) + NaHS (4 nmol), pyrrolidine dithiocarbamate (PDTC, 4 nmol) + NaHS (4 nmol), and L703606 (4 nmol) + NaHS (4 nmol). RESULTS: We identified a significant increase in the co-expression of c-Fos and CBS positive neurons in the NTS after 1 h and 3 h of restraint water-immersion stress compared to the expressions observed in the control group. Intra-NTS injection of NaHS at different doses significantly inhibited gastric motility in rats (P < 0.01). However, injection of saline, first injection NF-κB inhibitor PDTC or transient receptor potential vanilloid 1 (TRPV1) antagonist Capsazepine or NK1 receptor blockers L703606 and then injection NaHS did not produce significant changes (P > 0.05). CONCLUSION: NTS contains neurons co-expressing CBS and c-Fos, and the injection of NaHS into the NTS can suppress gastric motility in rats. This effect may be mediated by activating TRPV1 and NK1 receptors via the NF-κB channel.
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Sulfuro de Hidrógeno , Animales , Ratas , Sulfuro de Hidrógeno/farmacología , FN-kappa B , Núcleo Solitario , DeshidrataciónRESUMEN
Specific medications to combat cerebellar ataxias, a group of debilitating movement disorders characterized by difficulty with walking, balance and coordination, are still lacking. Notably, cerebellar microglial activation appears to be a common feature in different types of ataxic patients and rodent models. However, direct evidence that cerebellar microglial activation in vivo is sufficient to induce ataxia is still lacking. Here, by employing chemogenetic approaches to manipulate cerebellar microglia selectively and directly, we found that specific chemogenetic activation of microglia in the cerebellar vermis directly leads to ataxia symptoms in wild-type mice and aggravated ataxic motor deficits in 3-acetylpyridine (3-AP) mice, a classic mouse model of cerebellar ataxia. Mechanistically, cerebellar microglial proinflammatory activation induced by either chemogenetic M3D(Gq) stimulation or 3-AP modeling hyperexcites Purkinje cells (PCs), which consequently triggers ataxia. Blockade of microglia-derived TNF-α, one of the most important proinflammatory cytokines, attenuates the hyperactivity of PCs driven by microglia. Moreover, chemogenetic inhibition of cerebellar microglial activation or suppression of cerebellar microglial activation by PLX3397 and minocycline reduces the production of proinflammatory cytokines, including TNF-α, to effectively restore the overactivation of PCs and alleviate motor deficits in 3-AP mice. These results suggest that cerebellar microglial activation may aggravate the neuroinflammatory response and subsequently induce dysfunction of PCs, which in turn triggers ataxic motor deficits. Our findings thus reveal a causal relationship between proinflammatory activation of cerebellar microglia and ataxic motor symptoms, which may offer novel evidence for therapeutic intervention for cerebellar ataxias by targeting microglia and microglia-derived inflammatory mediators.
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Ataxia Cerebelosa , Ratones , Animales , Ataxia Cerebelosa/inducido químicamente , Células de Purkinje/fisiología , Microglía , Factor de Necrosis Tumoral alfa/farmacología , Cerebelo , CitocinasRESUMEN
The classical motor center cerebellum is one of the most consistent structures of abnormality in autism spectrum disorders (ASD), and neuropeptide oxytocin is increasingly explored as a potential pharmacotherapy for ASD. However, whether oxytocin targets the cerebellum for therapeutic effects remains unclear. Here, we report a localization of oxytocin receptor (OXTR) in Purkinje cells (PCs) of cerebellar lobule Crus I, which is functionally connected with ASD-implicated circuits. OXTR activation neither affects firing activities, intrinsic excitability, and synaptic transmission of normal PCs nor improves abnormal intrinsic excitability and synaptic transmission of PCs in maternal immune activation (MIA) mouse model of autism. Furthermore, blockage of OXTR in Crus I in wild-type mice does not induce autistic-like social, stereotypic, cognitive, and anxiety-like behaviors. These results suggest that oxytocin signaling in Crus I PCs seems to be uninvolved in ASD pathophysiology, and contribute to understanding of targets and mechanisms of oxytocin in ASD treatment.
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Trastorno del Espectro Autista , Trastorno Autístico , Ratones , Animales , Receptores de Oxitocina , Oxitocina , Células de PurkinjeRESUMEN
Introduction: ß-Glucosidase serves as the pivotal rate-limiting enzyme in the cellulose degradation process, facilitating the hydrolysis of cellobiose and cellooligosaccharides into glucose. However, the widespread application of numerous ß-glucosidases is hindered by their limited thermostability and low glucose tolerance, particularly in elevated-temperature and high-glucose environments. Methods: This study presents an analysis of a ß-glucosidase gene belonging to the GH1 family, denoted lqbg8, which was isolated from the metagenomic repository of Hehua hot spring located in Tengchong, China. Subsequently, the gene was cloned and heterologously expressed in Escherichia coli BL21(DE3). Post expression, the recombinant ß-glucosidase (LQBG8) underwent purification through a Ni affinity chromatography column, thereby enabling the in-depth exploration of its enzymatic properties. Results: LQBG8 had an optimal temperature of 70°C and an optimum pH of 5.6. LQBG8 retained 100 and 70% of its maximum activity after 2-h incubation periods at 65°C and 70°C, respectively. Moreover, even following exposure to pH ranges of 3.0-10.0 for 24 h, LQBG8 retained approximately 80% of its initial activity. Notably, the enzymatic prowess of LQBG8 remained substantial at glucose concentrations of up to 3 M, with a retention of over 60% relative activity. The kinetic parameters of LQBG8 were characterized using cellobiose as substrate, with Km and Vmax values of 28 ± 1.9 mg/mL and 55 ± 3.2 µmol/min/mg, respectively. Furthermore, the introduction of LQBG8 (at a concentration of 0.03 mg/mL) into a conventional cellulase reaction system led to an impressive 43.7% augmentation in glucose yield from corn stover over a 24-h period. Molecular dynamics simulations offered valuable insights into LQBG8's thermophilic nature, attributing its robust stability to reduced fluctuations, conformational changes, and heightened structural rigidity in comparison to mesophilic ß-glucosidases. Discussion: In summation, its thermophilic, thermostable, and glucose-tolerant attributes, render LQBG8 ripe for potential applications across diverse domains encompassing food, feed, and the production of lignocellulosic ethanol.