Huoxue Tongjiang decoction-resisted reflux esophagitis by activation stem cell factor/c-kit/interstitial cell of cajal pathway and regulating the T-helper 17/regulatory T-cells balance in rats

Background:Huoxue Tongjiang decoction(HXTJD)is an effective prescription for treating reflux esophagitis(RE).We investigated the effects of HXTJD on esophageal motility and mucosal inflammation in a rat RE model.Methods:Chemical composition of HXTJD was analyzed by ultrahigh-performance liquid chromatography Q-Orbitrap mass spectrometry(MS).The change rates of mean contraction tension forces,mean amplitudes,and mean frequencies for the lower esophageal sphincter(LES)were recorded using the isolated tissue bath system,mechanical tension transducer,and PowerLab physiological recorder.After weighing the stomach,the phenol red labeling method was used to measure the gastric emptying rate.The LES ultrastructure was observed through transmission electron microscopy.Immunofluorescence and western blotting were used to detect the number of interstitial cells of Cajal(ICC)and the expression levels of c-kit protein,connexin43(Cx43),and stem cell factor(SCF).Flow cytometric analysis and enzyme-linked immunosorbent assay were conducted to detect the percentages of T helper 17(Th17)cells and regulatory T(Treg)cells and the serum concentrations of interleukin 6(IL-6),interleukin 17(IL-17),and interleukin 10(IL-10)in the rats.Results:We identified 28 chemical constituents in HXTJD.Regarding esophageal motility,we revealed that HXTJD increased the mean contraction tension forces,mean amplitudes,and mean frequency change rate of LES and the gastric emptying rate;decreased stomach weight;and improved the LES ultrastructure.Additionally,HXTJD increased the number of ICC-positive cells,and c-kit,Cx43,and SCF expression levels.Regarding esophageal inflammation,HXTJD significantly decreased the percentage of Th17 cells,and IL-6 and IL-17 concentrations,and increased the percentage of Treg cells and IL-10 concentration.Conclusion:HXTJD was found to be efficacious in the rat RE model.It may promote esophageal motility and alleviate the inflammatory response by activating the SCF/c-kit/ICC pathway and regulating the Th17/Treg cell balance.

Therapeutic effect of Cistanche deserticola on defecation in senile constipation rat model through stem cell factor/C-kit signaling pathway

BACKGROUND Constipation is one of the chronic gastrointestinal functional diseases.It seriously affects the quality of life.Cistanche deserticola(C.deserticola)can treat constipation obviously,but its mechanism has not been clarified.We supposed that mechanism of it improved the intestinal motility by stimulating interstitial Cajal cells(ICC).Activation of the C-kit receptor on the surface of ICC is closely related to ICC function,and the stem cell factor(SCF)/C-kit signaling pathways plays an important role on it.To investigate the mechanism of how C.deserticola treats constipation,this study aimed to establish a constipation model in rats and explore the role of SCF/C-kit signaling pathway in the treatment.AIM To explore the SCF/C-kit signaling pathways in the role of C.deserticola for treatment of constipation by a constipation rat model.METHODS Forty-eight 8-mo-old Sprague–Dawley rats were divided into 4 groups by random weight method:Normal group(n=12),model group(n=12),C.deserticola group(n=12)and blocker group(n=12).The normal group received normal saline by gavage;the model group received loperamide by gavage;the blocker group received loperamide and C.deserticola by gavage,and STI571 was injected by intraperitoneally.During treatment,the weight,fecal granules and fecal quality were recorded every 10 d.On day 20 after model induction,the colon tissues of each group were removed.Hematoxylin and eosin staining was used to observe pathological changes.Expression levels of SCF,C-kit and Aquaporin genes were detected by immunohistochemistry,western blotting,and real-time-quantitative polymerase chain reaction.The colonic epithelial mitochondria and goblet cells were observed by transmission electron microscopy.RESULTS Compared with the normal group,as treatment progressed,the weight of rats in the model and blocker groups decreased significantly,the stool weight decreased,and the stool quality was dry(P<0.05).C.deserticola reversed the decrease in body weight and stool weight and improved stool quality.Histopathological analysis indicated that the colonic mucosal epithelium in the model group was incomplete,and the arrangement of the glands was irregular or damaged.Treatment with C.deserticola improved the integrity and continuity of the epithelial cells and regular arrangement of the glands.The blocking agents inhibited the effects of C.deserticola Immunohistochemistry and real-timequantitative polymerase chain reaction showed that expression of SCF and C-kit protein or genes in the colonic tissue of the model group was decreased(P<0.05),while treatment with C.deserticola increased protein or gene expression(P<0.05).Western blotting showed that expression of aquaporin APQ3 was increased,while the expression of Cx43 decreased in the model group.Treatment with C.deserticola inhibited expression of APQ3 and promoted expression of Cx43.Transmission electron microscopy showed that the mitochondria of the colonic epithelium in the model group were swollen and arranged disorderly,and microvilli were sparse.The condition was better in the C.deserticola group.Mice treated with STI571 blocker confirmed that blocking the SCF/C-kit pathway inhibited the improvement of constipation by C.deserticola.CONCLUSION C.deserticola improved defecation in rats with constipation,and the SCF/C-kit signaling pathway,which is a key link of ICC function,played an important role of the treatment.

Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility disturbance.The pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal cells.Moreover,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal cells.Cajal cells are the pacemakers of gastrointestinal motility.AIM To investigate the effects of Bifidobacterium lactis(B.lactis)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit pathway.METHODS The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 days.The tail group was given B.lactis BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/day.Hematoxylin&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and PCR.The fecal flora and mucosal flora of rats in each group were detected by 16S rRNA.RESULTS Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic intervention.Simulated microgravity reduced the expressions of SCF and c-kit,and increased the expressions of ERK and P-ERK in the gastric antrum of rats.However,after probiotic intervention,the expressions of SCF and ckit were increased,while the expressions of ERK and P-ERK were decreased,with statistical significance(P<0.05).In addition,simulated microgravity can reduce the operational taxonomic unit(OTU)of the overall intestinal flora of rats,B.lactis BLa80 can increase the OTU of rats,simulated microgravity can reduce the overall richness and diversity of stool flora of rats,increase the abundance of firmicutes in stool flora of rats,and reduce the abundance of Bacteroides in stool flora of rats,most of which are mainly beneficial bacteria.Simulated microgravity can increase the overall richness and diversity of mucosal flora,increase the abundance of Bacteroides and Desulphurides in the rat mucosal flora,and decrease the abundance of firmicutes,most of which are proteobacteria.After probiotics intervention,the overall Bacteroidetes trend in simulated microgravity rats was increased.CONCLUSION B.lactis BLa80 can ameliorate intestinal mucosal injury,regulate intestinal flora,inhibit ERK expression,and activate the SCF/c-kit signaling pathway,which may have a facilitating effect on gastrointestinal motility in simulated microgravity rats.

Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology

Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy patients.These aggregates alter protein-protein interactions and compromise transcriptional activity.In this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic factor.Overexpressio n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor aggregation.Conversely.knocking down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor aggregation.Our findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.

Functions of nuclear factor Y in nervous system development,function and health

Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 years,research has revealed that the nuclear factor Y complex controls many aspects of brain development,including differentiation,axon guidance,homeostasis,disease,and most recently regeneration.However,a complete understanding of transcriptional regulatory networks,including how the nuclear factor Y complex binds to specific CCAAT boxes to perform its function remains elusive.In this review,we explore the nuclear factor Y complex’s role and mode of action during brain development,as well as how genomic technologies may expand understanding of this key regulator of gene expression.

The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67, I^(2) = 0.00%). The combined effect of the interventions was significant(MD = 2.88, 95% CI: 1.53–4.22, P < 0.0001), indicating that the brain-derived neurotrophic factor levels of the children and adolescents in the exercise group were significantly higher than those in the control group. In conclusion, different types of exercise interventions significantly increased brain-derived neurotrophic factor levels in children and adolescents. However, because of the small sample size of this meta-analysis, more high-quality research is needed to verify our conclusions. This metaanalysis was registered at PROSPERO(registration ID: CRD42023439408).

Telencephalic stab wound injury induces regenerative angiogenesis and neurogenesis in zebrafish:unveiling the role of vascular endothelial growth factor signaling and microglia

After brain damage,regenerative angiogenesis and neurogenesis have been shown to occur simultaneously in mammals,suggesting a close link between these processes.However,the mechanisms by which these processes interact are not well understood.In this work,we aimed to study the correlation between angiogenesis and neurogenesis after a telencephalic stab wound injury.To this end,we used zebrafish as a relevant model of neuroplasticity and brain repair mechanisms.First,using the Tg(fli1:EGFP×mpeg1.1:mCherry)zebrafish line,which enables visualization of blood vessels and microglia respectively,we analyzed regenerative angiogenesis from 1 to 21 days post-lesion.In parallel,we monitored brain cell proliferation in neurogenic niches localized in the ventricular zone by using immunohistochemistry.We found that after brain damage,the blood vessel area and width as well as expression of the fli1 transgene and vascular endothelial growth factor(vegfaa and vegfbb)were increased.At the same time,neural stem cell proliferation was also increased,peaking between 3 and 5 days post-lesion in a manner similar to angiogenesis,along with the recruitment of microglia.Then,through pharmacological manipulation by injecting an anti-angiogenic drug(Tivozanib)or Vegf at the lesion site,we demonstrated that blocking or activating Vegf signaling modulated both angiogenic and neurogenic processes,as well as microglial recruitment.Finally,we showed that inhibition of microglia by clodronate-containing liposome injection or dexamethasone treatment impairs regenerative neurogenesis,as previously described,as well as injury-induced angiogenesis.In conclusion,we have described regenerative angiogenesis in zebrafish for the first time and have highlighted the role of inflammation in this process.In addition,we have shown that both angiogenesis and neurogenesis are involved in brain repair and that microglia and inflammation-dependent mechanisms activated by Vegf signaling are important contributors to these processes.This study paves the way for a better understanding of the effect of Vegf on microglia and for studies aimed at promoting angiogenesis to improve brain plasticity after brain injury.

Age-related driving mechanisms of retinal diseases and neuroprotection by transcription factor EB-targeted therapy

Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

During the development of the nervous system,there is an overproduction of neurons and synapses.Hebbian competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or strengthening.We have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse consolidation.The purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this process.In particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental competition.The dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific endings.We describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon terminals.The downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary synapses.Finally,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to reduce transmitter release and promote withdrawal of the most unfavorable nerve terminals during elimination(the weakest in acetylcholine release and those that have already become silent).The main findings contribute to a better understanding of punishment-rewarding interactions between nerve endings during development.Identifying the molecular targets and signaling pathways that allow synapse consolidation or withdrawal of synapses in different situations is important for potential therapies in neurodegenerative diseases.

The cGAS-STING-interferon regulatory factor 7 pathway regulates neuroinflammation in Parkinson's disease

Interferon regulatory factor 7 plays a crucial role in the innate immune response.However,whether interferon regulatory factor 7-mediated signaling contributes to Parkinson's disease remains unknown.Here we report that interferon regulatory factor 7 is markedly up-regulated in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced mouse model of Parkinson's disease and co-localizes with microglial cells.Both the selective cyclic guanosine monophosphate adenosine monophosphate synthase inhibitor RU.521 and the stimulator of interferon genes inhibitor H151 effectively suppressed interferon regulatory factor 7 activation in BV2 microglia exposed to 1-methyl-4-phenylpyridinium and inhibited transformation of mouse BV2 microglia into the neurotoxic M1 phenotype.In addition,si RNA-mediated knockdown of interferon regulatory factor 7 expression in BV2 microglia reduced the expression of inducible nitric oxide synthase,tumor necrosis factorα,CD16,CD32,and CD86 and increased the expression of the anti-inflammatory markers ARG1 and YM1.Taken together,our findings indicate that the cyclic guanosine monophosphate adenosine monophosphate synthase-stimulator of interferon genes-interferon regulatory factor 7 pathway plays a crucial role in the pathogenesis of Parkinson's disease.

c-KIT受体蛋白在犬皮肤肥大细胞瘤中的作用及其应用

皮肤肥大细胞瘤(MCT)是犬发生率较高的皮肤肿瘤类型之一,多发于老年犬,是危害犬类健康的重要疾病之一。c-KIT受体蛋白是一种跨膜蛋白,具有酪氨酸激酶活性,可调控肥大细胞的生长和分化。本文旨在阐明c-KIT受体蛋白在犬皮肤MCT中的作用及其应用,总结了c-KIT受体蛋白在肥大细胞增殖调控中的作用,深入探讨了c-KIT受体蛋白检测在犬皮肤MCT诊断中的应用价值,明确了c-KIT受体蛋白在犬皮肤MCT发生发展中的作用,同时也为进一步研究c-KIT受体蛋白在犬皮肤MCT中的发病机制提供了重要参考。

温胃阳汤对功能性消化不良大鼠肥大细胞活化及SCF/c-Kit信号通路的影响

目的:基于肥大细胞活化及干细胞因子(stem cell factor,SCF)/受体酪氨酸激酶c-Kit信号通路探讨温胃阳汤治疗大鼠功能性消化不良的作用机制。方法:将60只SD大鼠随机分为空白组,模型组,雷尼替丁组及温胃阳汤低、中、高剂量组,每组10只。空白组大鼠不予造模,其他各组采用夹尾刺激加不规则喂养复合番泻叶法建立大鼠功能性消化不良模型,模型建立后,空白组及模型组灌胃给予生理盐水,温胃阳汤低、中、高剂量组和雷尼替丁组则分别用温胃阳汤(0.743 g/mL、1.485 g/mL和2.970 g/mL)及盐酸雷尼替丁胶囊(3 g/L)灌胃。治疗结束后,以碳墨推进法测定小肠推进率;采用甲苯胺蓝染色观察大鼠十二指肠组织肥大细胞并计数;ELISA测定大鼠十二指肠中肥大细胞类胰蛋白酶(mast cell tryptase,MCT)和组胺(histamine,HA)的含量;RT-qPCR检测十二指肠中SCF和c-Kit mRNA的表达;Western blot和免疫组化检测十二指肠中SCF和c-Kit蛋白的表达水平。结果:与模型组相比,温胃阳汤治疗显著提高大鼠的小肠推进率(P<0.05);ELISA结果显示,温胃阳汤治疗可减少大鼠十二指肠黏膜组织肥大细胞数量及MCT和HA含量(P<0.05);Western blot和免疫组化结果表明,温胃阳汤治疗可上调大鼠十二指肠组织c-Kit和SCF蛋白的表达水平(P<0.05),增加SCF和c-Kit阳性细胞数(P<0.05);RT-qPCR结果显示,WWYD治疗可上调大鼠十二指肠组织c-Kit和SCF mRNA的表达(P<0.01)。而且,小肠推进率分别与MCT和HA含量呈负相关,与SCF和c-Kit的表达呈正相关。结论:温胃阳汤能促进大鼠十二指肠动力,其作用机制可能与抑制大鼠十二指肠MCT和HA的生成,及激活SCF/c-Kit信号通路有关。

SCF/c-Kit在小鼠隐睾模型中的表达变化及意义

目的:观察干细胞因子(SCF)与原癌基因c-Kit在小鼠隐睾模型睾丸组织中的表达变化。方法:将妊娠BALB/c小鼠随机分成A、B、C、D、E五组;在妊娠第12~21天持续10 d经给予氟他胺灌胃,剂量依次为0 mg/kg、150 mg/kg、300 mg/kg、500 mg/kg、700 mg/kg,在子代小鼠出生后第8周时采用Real-Time PCR法检测其睾丸组织SCF mRNA的相对表达量,运用量子点技术检测c-Kit在组织中的表达情况。结果:小鼠隐睾模型诱导成功。五组中小鼠睾丸组织SCF mRNA的相对表达量分别为1.00±0.01、0.78±0.04、0.61±0.03、0.45±0.05、0.35±0.03,SCF mRNA的表达依次降低,与A组相比(P<0.05)。c-Kit在实验组的表达明显少于对照组。结论:在氟他胺诱导的小鼠隐睾模型中,小鼠睾丸组织SCF mRNA与c-Kit表达的下降可能是隐睾小鼠生精功能受损的重要原因之一。

基于drop-off ddPCR方法检测急性髓系白血病C-KIT基因N822位点突变及其临床应用

目的:建立急性髓系白血病(acute myeloid leukemia, AML)患者C-KIT基因N822位点突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)定量检测方法,并评价其临床应用价值。方法:针对C-KIT基因第17外显子设计一对引物及探针,优化drop-off ddPCR反应条件及体系,评价该方法的特异性、灵敏度、重复性,使用所建立的方法对140例已行Sanger测序的AML初诊患者骨髓标本进行检测,并用二代测序(next generation sequencing, NGS)验证结果;用drop-off ddPCR对3例阳性患者化疗后C-KIT突变频率进行动态监测。结果:drop-off ddPCR检测C-KIT基因N822位点突变的最适退火温度为54℃,空白检测限为1.62拷贝数/μL,最低检测下限为10.12拷贝数/μL,线性良好。140例AML初诊患者样本中Sanger测序检出2例阳性(1.4%),而ddPCR共检出突变7例(5.0%),突变频率为0.29%~7.41%;进一步应用常规NGS方法对ddPCR阳性样本进行验证,共检出阳性3例(2.1%),等位基因频率为1.26%~8.00%。动态监测3例阳性患者C-KIT突变频率,结果显示治疗达完全缓解时C-KIT突变频率明显下降甚至降低至0。结论:本研究建立了检测C-KIT基因N822位点突变的drop-off ddPCR技术,具有良好的方法学检测性能,其灵敏度高于Sanger测序和NGS,有望用于阳性患者缓解后的可检测残留疾病监测及治疗指导。

Significant risk factors for intensive care unit-acquired weakness:A processing strategy based on repeated machine learning

BACKGROUND Intensive care unit-acquired weakness(ICU-AW)is a common complication that significantly impacts the patient's recovery process,even leading to adverse outcomes.Currently,there is a lack of effective preventive measures.AIM To identify significant risk factors for ICU-AW through iterative machine learning techniques and offer recommendations for its prevention and treatment.METHODS Patients were categorized into ICU-AW and non-ICU-AW groups on the 14th day post-ICU admission.Relevant data from the initial 14 d of ICU stay,such as age,comorbidities,sedative dosage,vasopressor dosage,duration of mechanical ventilation,length of ICU stay,and rehabilitation therapy,were gathered.The relationships between these variables and ICU-AW were examined.Utilizing iterative machine learning techniques,a multilayer perceptron neural network model was developed,and its predictive performance for ICU-AW was assessed using the receiver operating characteristic curve.RESULTS Within the ICU-AW group,age,duration of mechanical ventilation,lorazepam dosage,adrenaline dosage,and length of ICU stay were significantly higher than in the non-ICU-AW group.Additionally,sepsis,multiple organ dysfunction syndrome,hypoalbuminemia,acute heart failure,respiratory failure,acute kidney injury,anemia,stress-related gastrointestinal bleeding,shock,hypertension,coronary artery disease,malignant tumors,and rehabilitation therapy ratios were significantly higher in the ICU-AW group,demonstrating statistical significance.The most influential factors contributing to ICU-AW were identified as the length of ICU stay(100.0%)and the duration of mechanical ventilation(54.9%).The neural network model predicted ICU-AW with an area under the curve of 0.941,sensitivity of 92.2%,and specificity of 82.7%.CONCLUSION The main factors influencing ICU-AW are the length of ICU stay and the duration of mechanical ventilation.A primary preventive strategy,when feasible,involves minimizing both ICU stay and mechanical ventilation duration.

哺乳动物毛色候选基因c-KIT的研究进展

哺乳动物的皮毛颜色主要受毛发中黑色素的种类和数量影响。c-KIT基因编码一种酪氨酸激酶跨膜受体,被称为肥大/干细胞生长因子受体,与黑色素生物合成相关。c-KIT基因突变会抑制干细胞生长因子受体功能,导致黑色素细胞的生成、成熟、增殖、分化和迁移等过程受到影响。本文就哺乳动物毛色形成的机制和主效基因、c-KIT基因的作用机理及其对哺乳动物毛色的影响进行综述,以期为深入研究哺乳动物毛色遗传机制以及不同毛色的选种和选育提供参考依据。

Are TrkB receptor agonists the right tool to fulfill the promises for a therapeutic value of the brain-derived neurotrophic factor?

Brain-derived neurotrophic factor signaling via its receptor tro pomyosin receptor kinase B regulates several crucial physiological processes.It has been shown to act in the brain,promoting neuronal survival,growth,and plasticity as well as in the rest of the body where it is involved in regulating for instance aspects of the metabolism.Due to its crucial and very pleiotro pic activity,reduction of brain-derived neurotrophic factor levels and alterations in the brain-derived neurotrophic factor/tropomyosin receptor kinase B signaling have been found to be associated with a wide spectrum of neurological diseases.Howeve r,because of its poor bioavailability and pharmacological properties,brain-derived neurotrophic factor itself has a very low therapeutic value.Moreover,the concomitant binding of exogenous brain-derived neurotrophic factor to the p75 neurotrophin receptor has the potential to elicit several unwanted and deleterious side effects.Therefo re,developing tools and approaches to specifically promote tropomyosin receptor kinase B signaling has become an important goal of translational research.Among the newly developed tools are different categories of tropomyosin receptor kinase B receptor agonist molecules.In this review,we give a comprehensive description of the diffe rent tro pomyosin receptor kinase B receptor agonist drugs developed so far and of the res ults of their application in animal models of several neurological diseases.Moreover,we discuss the main benefits of tropomyosin receptor kinase B receptor agonists,concentrating especially on the new tropomyosin receptor kinase B agonist antibodies.The benefits observed both in vitro and in vivo upon application of tropomyosin receptor kinase B receptor agonist drugs seem to predominantly depend on their general neuroprotective activity and their ability to promote neuronal plasticity.Moreover,tro pomyosin receptor kinase B agonist antibodies have been shown to specifically bind the tropomyosin receptor kinase B receptor and not p75 neurotrophin receptor.Therefore,while,based on the current knowledge,the tropomyosin receptor kinase B receptor agonists do not seem to have the potential to reve rse the disease pathology per se,promoting brainderived neurotrophic factor/tro pomyosin receptor kinase B signaling still has a very high therapeutic relevance.

Hepatocyte growth factor promotes retinal pigment epithelium cell activity through MET/AKT signaling pathway

AIM:To explore the effects of hepatocyte growth factor(HGF)on retinal pigment epithelium(RPE)cell behaviors.METHODS:The human adult retinal pigment epithelial cell line-19(ARPE-19)were treated by HGF or mesenchymalepithelial transition factor(MET)inhibitor SU11274 in vitro.Cell viability was detected by a Cell Counting Kit-8 assay.Cell proliferation and motility was detected by a bromodeoxyuridine incorporation assay and a wound healing assay,respectively.The expression levels of MET,phosphorylated MET,protein kinase B(AKT),and phosphorylated AKT proteins were determined by Western blot assay.The MET and phosphorylated MET proteins were also determined by immunofluorescence assay.RESULTS:HGF increased ARPE-19 cells’viability,proliferation and migration,and induced an increase of phosphorylated MET and phosphorylated AKT proteins.SU11274 significantly reduced cell viability,proliferation,and migration and decreased the expression of MET and AKT proteins.SU11274 suppressed HGF-induced increase of viability,proliferation,and migration in ARPE-19 cells.Additionally,SU11274 also blocked HGF-induced phosphorylation of MET and AKT proteins.CONCLUSION:HGF enhances cellular viability,proliferation,and migration in RPE cells through the MET/AKT signaling pathway,whereas this enhancement is suppressed by the MET inhibitor SU11274.HGF-induced MET/AKT signaling might be a vital contributor of RPE cells survival.

The roles of macrophage migration inhibitory factor in retinal diseases

Macrophage migration inhibitory factor(MIF),a multifunctional cytokine,is secreted by various cells and participates in inflammatory reactions,including innate and adaptive immunity.There are some evidences that MIF is involved in many vitreoretinal diseases.For example,MIF can exacerbate many types of uveitis;measurements of MIF levels can be used to monitor the effectiveness of uveitis treatment.MIF also alleviates trauma-induced and glaucoma-induced optic nerve damage.Furthermore,MIF is critical for retinal/choroidal neovascularization,especially complex neovascularization.MIF exacerbates retinal degeneration;thus,anti-MIF therapy may help to mitigate retinal degeneration.MIF protects uveal melanoma from attacks by natural killer cells.The mechanism underlying the effects of MIF in these diseases has been demonstrated:it binds to cluster of differentiation 74,inhibits the c-Jun N-terminal kinase pathway,and triggers mitogen-activated protein kinases,extracellular signal-regulated kinase-1/2,and the phosphoinositide-3-kinase/Akt pathway.MIF also upregulates Toll-like receptor 4 and activates the nuclear factor kappa-B signaling pathway.This review focuses on the structure and function of MIF and its receptors,including the effects of MIF on uveal inflammation,retinal degeneration,optic neuropathy,retinal/choroidal neovascularization,and uveal melanoma.

Spatial-temporal differentiation and influencing factors of rural settlements in mountainous areas: an example of Liangshan Yi Autonomous Prefecture, Southwestern China

Rural settlement is the basic spatial unit for compact communities in rural area. Scientific exploration of spatial-temporal differentiation and its influencing factors is the premise of spatial layout rationalization. Based on land use data of Liangshan Yi Autonomous Prefecture(hereinafter referred to as Liangshan Prefecture) in Sichuan Province, China from 1980 to 2020, compactness index, fractal dimension, imbalance index, location entropy and the optimal parameters-based geographical detector(OPGD) model are used to analyze the spatial-temporal evolution of the morphological characteristics of rural settlements, and to explore the influence of natural geographical factors, socioeconomic factors, and policy factors on the spatial differentiation of rural settlements. The results show that:(1) From 1980 to 2020, the rural settlements area in Liangshan Prefecture increased by 15.96 km^(2). In space, the rural settlements are generally distributed in a local aggregation, dense in the middle and sparse around the periphery. In 2015, the spatial density and expansion index of rural settlements reached the peak.(2) From 1980 to 2020, the compactness index decreased from 0.7636 to 0.7496, the fractal dimension increased from 1.0283 to 1.0314, and the fragmentation index decreased from 0.1183 to 0.1047. The spatial morphological structure of rural settlements tended to be loose, the shape contour tended to be complex, the degree of fragmentation decreased, and the spatial distribution was significantly imbalanced.(3) The results of OPGD detection in 2015 show that the influence of each factor is slope(0.2371) > traffic accessibility(0.2098) > population(0.1403) > regional GDP(0.1325) > elevation(0.0987) > poverty alleviation(0). The results of OPGD detection in 2020 show that the influence of each factor is slope(0.2339) > traffic accessibility(0.2198) > population(0.1432) > regional GDP(0.1219) > poverty alleviation(0.0992) > elevation(0.093). Natural geographical factors(slope and elevation) are the basic factors affecting the spatial distribution of rural settlements, and rural settlements are widely distributed in the river valley plain and the second half mountain area. Socioeconomic factors(traffic accessibility, population, and regional GDP) have a greater impact on the spatial distribution of rural settlements, which is an important factor affecting the spatial distribution of rural settlements. Policy factors such as poverty alleviation relocation have an indispensable impact on the spatial distribution of rural settlements. The research results can provide decisionmaking basis for the spatial arrangement of rural settlements in Liangshan Prefecture, and optimize the implementation of rural revitalization policies.