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1.
《Mucosal immunology》2021,14(3):691-702
Plectin, a highly versatile cytolinker protein, provides tissues with mechanical stability through the integration of intermediate filaments (IFs) with cell junctions. Here, we hypothesize that plectin-controlled cytoarchitecture is a critical determinant of the intestinal barrier function and homeostasis. Mice lacking plectin in an intestinal epithelial cell (IEC; PleΔIEC) spontaneously developed colitis characterized by extensive detachment of IECs from the basement membrane (BM), increased intestinal permeability, and inflammatory lesions. Moreover, plectin expression was reduced in the colons of ulcerative colitis (UC) patients and negatively correlated with the severity of colitis. Mechanistically, plectin deficiency in IECs led to aberrant keratin filament (KF) network organization and the formation of dysfunctional hemidesmosomes (HDs) and intercellular junctions. In addition, the hemidesmosomal α6β4 integrin (Itg) receptor showed attenuated association with KFs, and protein profiling revealed prominent downregulation of junctional constituents. Consistent with the effects of plectin loss in the intestinal epithelium, plectin-deficient IECs exhibited remarkably reduced mechanical stability and limited adhesion capacity in vitro. Feeding mice with a low-residue liquid diet that reduced mechanical stress and antibiotic treatment successfully mitigated epithelial damage in the PleΔIEC colon.  相似文献   
2.
《Immunobiology》2021,226(6):152146
BackgroundImmune epitopes of allergens are pivotal for development of novel diagnostic and therapeutic modalities. Present study aims to identify antigenic determinants of Per a 5, a clinically relevant cross reactive cockroach allergen.MethodsThe three dimensional structure of Per a 5 was modelled using Modeller 9v11 software. A combination of sequence and structure based computational tools were employed for predicting B cell epitopes. Epitopes were synthesized and immunoreactivity was assessed by ELISA using cockroach hypersensitive patient’s sera. Cross-reactivity potential of predicted epitopes was assessed with SDAP and ConSurf and validated by IgE ELISA with fungal and mite hypersensitive patient’s sera.ResultsPer a 5 structure exhibited good quality factor in ERRAT and high stereochemical stability. In silico analysis revealed six B cell epitopes (BC-P1 to P6). BC-P3 demonstrated significant IgE binding followed by BC-P2 and BC-P1 with cockroach hypersensitive patient’s sera. Per a 5 epitopes demonstrate considerable similarity with broad spectrum of allergens from fungal, mites, helminths, fruits and nuts. Analysis of PD values indicate BC-P4 to be well conserved among dust mite and helminth GSTs (8.89, 10.63 and 10.69 with D. pteronyssinus, W. bancrofti and F. hepatica respectively). ConSurf analysis of Per a 5 revealed specific enrichment of evolutionarily similar amino acid residues in BC-P2 (with fungal and mite GSTs) and BC-P4 (with mite and helminth GSTs). Further, IgE binding analysis of epitopes demonstrate BC-P2, BC-P3 and BC-P5 as high IgE binders in fungal hypersensitive sera while BC-P1, BC-P2, BC-P4 and BC-P5 demonstrated significant IgE binding with mite hypersensitive sera.ConclusionsAmong the predicted epitopes, BC-P3 demonstrates maximal IgE binding ability. Computational analysis suggests strong evolutionary conservation and cross reactive potential of BC-P4 with allergens in dust mite and helminths. ELISA highlights predictive potential of analysing evolutionarily conserved residues for uncovering potentially cross reactive antigenic determinants.General significanceImmune epitopes of Per a 5 were identified for aiding molecular diagnosis and potential cross reactivity.  相似文献   
3.
《The journal of pain》2019,20(9):1040-1047
Tolerance to the antinociceptive effect of mu-opioid receptor agonists, such as morphine and fentanyl, greatly limits their effectiveness for long-term use to treat pain. Clinical studies have shown that combination therapy and opioid rotation can be used to enhance opioid-induced antinociception once tolerance has developed. The mechanism and brain regions involved in these processes are unknown. The purpose of this study was to evaluate the contribution of the ventrolateral periaqueductal gray (vlPAG) to antinociceptive tolerance and cross-tolerance between administration and co-administration of morphine and fentanyl. Tolerance was induced by pretreating rats with morphine or fentanyl or low-dose combination of morphine and fentanyl into the vlPAG followed by an assessment of the cross-tolerance to the other opioid. In addition, tolerance to the combined treatment was assessed. Cross-tolerance did not develop between repeated vlPAG microinjections of morphine and fentanyl. Likewise, there was no evidence of cross-tolerance from morphine or fentanyl to the co-administration of morphine and fentanyl. Co-administration did not cause cross-tolerance to fentanyl. Cross-tolerance was only evident to morphine or morphine and fentanyl combined in rats pretreated with co-administration of low doses of morphine and fentanyl. This finding is consistent with the functionally selective signaling that has been reported for antinociception and tolerance after morphine and fentanyl binding to the mu-opioid receptor. This research supports the notion that combination therapy and opioid rotation may be useful clinical practices to decrease opioid tolerance and other side effects.PerspectiveThis preclinical study shows that there is a decrease in cross-tolerance between morphine and fentanyl within the periaqueductal gray, which is a key brain region in opioid antinociception and tolerance.  相似文献   
4.
When living organisms become sick as a result of a bacterial infection, a suite of brain-mediated responses occur, including fever, anorexia and sleepiness. Systemic administration of lipopolysaccharide (LPS), a common constituent of bacterial cell walls, increases body temperature and non-rapid eye movement (NREM) sleep in animals and induces the production of pro-inflammatory prostaglandins (PGs). PGE2 is the principal mediator of fever, and both PGE2 and PGD2 regulate sleep–wake behavior. The extent to which PGE2 and PGD2 are involved in the effect of LPS on NREM sleep remains to be clarified. Therefore, we examined LPS-induced changes in body temperature and NREM sleep in mice with nervous system-specific knockouts (KO) for the PGE2 receptors type EP3 or EP4, in mice with total body KO of microsomal PGE synthase-1 or the PGD2 receptor type DP, and in mice treated with the cyclooxygenase (COX) inhibitor meloxicam. We observed that LPS-induced NREM sleep was slightly attenuated in mice lacking EP4 receptors in the nervous system, but was not affected in any of the other KO mice or in mice pretreated with the COX inhibitor. These results suggest that the effect of LPS on NREM sleep is partially dependent on PGs and is likely mediated mainly by other pro-inflammatory substances. In addition, our data show that the main effect of LPS on body temperature is hypothermia in the absence of nervous system EP3 receptors or in the presence of a COX inhibitor.  相似文献   
5.
《Clinical neurophysiology》2020,131(1):213-224
ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology.  相似文献   
6.

Background

We have recently shown that human epididymis protein 4 (HE4) levels correlate with the severity of cystic fibrosis (CF) lung disease. However, there are no data on how HE4 levels alter in patients receiving CFTR modulating therapy.

Methods

In this retrospective clinical study, 3 independent CF patient cohorts (US-American: 29, Australian: 12 and Irish: 19 cases) were enrolled carrying at least one Class III CFTR CF-causing mutation (p.Gly551Asp) and being treated with CFTR potentiator ivacaftor. Plasma HE4 was measured by immunoassay before treatment (baseline) and 1–6?months after commencement of ivacaftor, and were correlated with FEV1 (% predicted), sweat chloride, C-reactive protein (CRP) and body mass index (BMI).

Results

After 1?month of therapy, HE4 levels were significantly lower than at baseline and remained decreased up to 6?months. A significant inverse correlation between absolute and delta values of HE4 and FEV1 (r?=??0.5376; P?<?.001 and r?=??0.3285; P?<?.001), was retrospectively observed in pooled groups, including an independent association of HE4 with FEV1 by multiple regression analysis (β?=??0.57, P?=?.019). Substantial area under the receiver operating characteristic curve (ROC-AUC) value was determined for HE4 when 7% mean change of FEV1 (0.722 [95% CI 0.581–0.863]; P?=?.029) were used as classifier, especially in the first 2?months of treatment (0.806 [95% CI 0.665–0.947]; P?<?.001).

Conclusions

This study shows that plasma HE4 levels inversely correlate with lung function improvement in CF patients receiving ivacaftor. Overall, this potential biomarker may be of value for routine clinical and laboratory follow-up of CFTR modulating therapy.  相似文献   
7.
目的:探讨雌性SD大鼠切除卵巢后机体尿DPD及血1,25-(0H)2D3变化与骨质量的相关性。方法:40X雌性SD大鼠随机分为卵巢切除组(OVX组)和假手术组(Sham组),分别于术后12、24周取材。运用双能X线骨密度仪测L1、股骨、股骨颈骨密度,ELISA法测尿DPD浓度,激素放免法测血1,25-(OH)2D3浓度,光测弹性仪测L1压缩强度极限、弹性模量及右侧股骨弯曲破坏栽荷,不脱钙骨切片技术观察胫骨上段骨组织形态结构并计量分析,对实验数据进行相关性分析。结果:术后OVX组除尿DPD/Cr明显升高外,其他检测指标均较Sham组低,且随术后时间推移持续下降,差异有统计学意义。相关分析显示:尿DPD/Cr与腰椎、股骨密度、椎体压缩强度极限、股骨弯曲破坏荷载和骨小梁面积均呈负相关。血清1,25-(OH)2D3水平与腰椎、股骨、股骨颈密度、骨小梁面积、椎体压缩强度极限和股骨弯曲破坏荷载呈正相关。结论:大鼠卵巢切除后尿DPD、血1,25-(0H)2D3水平变化与骨质量显著相关,可以通过检测尿DPD、血1,25-(0H)2D,水平变化预测骨质量。  相似文献   
8.
Spatial analysis of (90)Sr artificial radionuclide in consequence of global fallout and Chernobyl nuclear accident has been carried out by using the point cumulative semivariogram (PCSV) technique based on 40 surface water station measurements in Keban Dam Lake during March, April, and May 2006. This technique is a convenient tool in obtaining the regional variability features around each sampling point, which yields the structural effects also in the vicinity of the same point. It presents the regional effect of all the other sites within the study area on the site concerned. In order to see to change of (90)Sr, the five models are constituted. Additionally, it provides a measure of cumulative similarity of the regional variable, (90)Sr, around any measurement site and hence it is possible to draw regional similarity maps at any desired distance around each station. In this paper, such similarity maps are also drawn for a set of distances. (90)Sr activities in lake that distance approximately 4.5 km from stations show the maximum similarity.  相似文献   
9.
目的探讨在常规西医治疗的基础上加用活血解毒中药对不稳定型心绞痛的治疗效果,观察治疗前后不稳定型心绞痛患者中医主症计分、血瘀证计分、心绞痛计分、高敏C反应蛋白(hs—CRP)和血脂等指标的变化。方法将介入治疗后不稳定型心绞痛患者61例随机分为活血解毒组(30例)与活血组(31例)。两组均服药两周,两周后对治疗前后中医主症计分、血瘀证计分、心绞痛计分、实验室指标、治疗前后心电图进行观察;以后每3个月门诊或电话随访1次,随访6个月,重点观察生存质量、终点指标发生的情况。结果活血解毒组治疗后可显著降低冠心病不稳定型心绞痛患者的hs~CRP水平,而活血组治疗后效果不显著(P〉0.05)。与活血组相比,活血解毒组有进一步降低不稳定型心绞痛患者心绞痛计分的作用趋势。结论在西医常规治疗基础上加用活血解毒药物可降低介入后不稳定型心绞痛患者的hs—CRP水平,改善心绞痛症状。  相似文献   
10.
《世界针灸杂志》2023,33(3):191-197
“Long COVID” is a sustained symptom following infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). According to recent statistics, at least 65 million people have long COVID, which poses a long-term threat to human health. The pathogenic mechanisms of coronavirus disease 2019 (COVID-19) are complex and affect multiple organs and systems. Common symptoms include palpitations, breathing difficulties, attention and memory deficits, fatigue, anxiety, and depression. It is difficult to achieve satisfactory treatment effect with a single intervention. Currently, treatment strategies for long COVID are still in the exploratory stage, and there is an urgent need to find appropriate and effective methods for long COVID treatment. Traditional Chinese medicine is effective in treating the various phases of COVID-19. Previous studies have shown that acupoint stimulation therapy is effective in improving palpitations, dyspnea, cognitive impairment, anxiety, depression, and other symptoms in patients. According to previous studies, acupoint stimulation may improve various symptoms related to long COVID. This paper discusses the potential application value of acupoint stimulation in the treatment of long COVID-related symptoms, based on the common sequelae of various systems involved in long COVID, and the effect of acupoint stimulation in the treatment of similar symptoms and diseases in recent years.  相似文献   
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