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OBJECTIVE: To study the clinical features and recurrence factors of myelin oligodendrocyte glycoprotein (MOG) antibody disease in children and the effect of recurrence prevention regimens. METHODS: A retrospective analysis was performed on the medical data of 41 children with MOG antibody disease who were hospitalized in the Department of Pediatric Neurology, Xiangya Hospital of Central South University, from December 2014 to September 2020. According to the presence or absence of recurrence, they were divided into a monophasic course group (n=19) and a recurrence group (n=22). According to whether preventive treatment for recurrence was given, the children with recurrence were further divided into a preventive treatment group and a non-preventive treatment group. The clinical features were analyzed for all groups, and the annualized relapse rate (ARR) was compared before and after treatment with prevention regimens. RESULTS: For these 41 children, acute disseminated encephalomyelitis was the most common initial manifestation and was observed in 23 children (56%). Of the 41 children, 22 (54%) experienced recurrence, with 57 recurrence events in total, among which optic neuritis was the most common event (17/57, 30%). The proportion of children in the recurrence group who were treated with corticosteroids for less than 3 months in the acute phase was higher than that in the monophasic course group (64% vs 32%; P < 0.05). There was no significant difference in the ARR between the preventive treatment and non-preventive treatment groups (P > 0.05). The assessment of preventive treatment regimens for 32 cases showed that the children treated with rituximab or azathioprine had a significant reduction in the ARR during treatment (P < 0.05). CONCLUSIONS: More than half of the children with MOG antibody disease may experience recurrence. Most children with recurrence are treated with corticosteroids for less than 3 months in the acute phase. Rituximab and azathioprine may reduce the risk of recurrence.
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Autoanticorpos , Neurite Óptica , Criança , Humanos , Glicoproteína Mielina-Oligodendrócito , Recidiva , Estudos RetrospectivosRESUMO
OBJECTIVE: To study the clinical features of the diseases associated with aminoacyl-tRNA synthetases (ARS) deficiency. METHODS: A retrospective analysis was performed of the clinical and gene mutation data of 10 children who were diagnosed with ARS gene mutations, based on next-generation sequencing from January 2016 to October 2019. RESULTS: The age of onset ranged from 0 to 9 years among the 10 children. Convulsion was the most common initial symptom (7 children). Clinical manifestations included ataxia and normal or mildly retarded intellectual development (with or without epilepsy; n=4) and onset of epilepsy in childhood with developmental regression later (n=2). Some children experienced disease onset in the neonatal period and had severe epileptic encephalopathy, with myoclonus, generalized tonic-clonic seizure, and convulsive seizure (n=4); 3 had severe delayed development, 2 had feeding difficulty, and 1 had hearing impairment. Mutations were found in five genes: 3 had novel mutations in the AARS2 gene (c.331G>C, c.2682+5G>A, c.2164C>T, and c.761G>A), 2 had known mutations in the DARS2 gene (c.228-16C>A and c.536G>A), 1 had novel mutations in the CARS2 gene (c.1036C>T and c.323T>G), 1 had novel mutations in the RARS2 gene (c.1210A>G and c.622C>T), and 3 had novel mutations in the AARS gene (c.1901T>A, c.229C>T, c.244C>T, c.961G>C, c.2248C>T, and Chr16:70298860-70316687del). CONCLUSIONS: A high heterogeneity is observed in the clinical phenotypes of the diseases associated with the ARS deficiency. A total of 14 novel mutations in 5 genes are reported in this study, which enriches the clinical phenotypes and genotypes of the diseases associated with ARS deficiency.
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Aminoacil-tRNA Sintetases/genética , Criança , Epilepsia , Humanos , Mutação , Fenótipo , Estudos RetrospectivosRESUMO
BACKGROUND: The implementation of allergen immunotherapy (AIT) requires extensive knowledge of allergen distribution in the region to identify high-risk regions for AIT utilization. However, the geographical distribution patterns of the major Dermatophagoides allergens in China remain unclear despite the increasing prevalence of these allergens. METHODS: We performed comprehensive database searches of articles demonstrating the distribution patterns of Dermatophagoides-sensitized allergic rhinitis (AR) and allergic asthma (AA) in China, published between 1990 and 2017. RESULTS: We retrieved 163 articles encompassing 114,302 allergen-positive cases to generate the distribution maps. The rate of sensitization to Dermatophagoides pteronyssinus(D. pteronyssinus)and Dermatophagoides farinae (D. farinae) was similar in patients with AR (75.1 vs. 75.2%, p > 0.05) but not in those with AA (78.5 vs. 77.7%, p = 0.041). Patients with AR and AA shared similar regional distribution patterns of both D. pteronyssinus and D. farinae sensitization, which were highest in the southern and central parts of China and lowest in the northern regions, especially in the Northwest. The overall rate of sensitization to D. pteronyssinus and D. farinae was significantly higher in patients with AA (p < 0.001). Additionally, the annual mean temperature and humidity were the 2 major determinants of D. pteronyssinus and D. farinae sensitization in AR and of D. pteronyssinus sensitization in AA, whereas the annual mean temperature was the sole determinant for D. farinae sensitization in AA. CONCLUSION: These findings may inform clinicians of the strategies for the prevention of Dermatophagoides sensitization and may be of benefit to the future clinical management of allergic diseasesassociated with sensitization to Dermatophagoides mites.
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Antígenos de Dermatophagoides/imunologia , Asma/epidemiologia , Asma/imunologia , Pyroglyphidae/imunologia , Rinite Alérgica/epidemiologia , Rinite Alérgica/imunologia , Animais , China/epidemiologia , Meio Ambiente , Feminino , Geografia Médica , Humanos , Imunização , Masculino , Prevalência , Vigilância em Saúde Pública , Curva ROCRESUMO
Purpose: Epithelial-mesenchymal transition (EMT) involved in asthmatic airway remodeling. Thymic stromal lymphopoietin (TSLP), an epithelial-derived cytokine, was a key component in airway immunological response in asthma. But the role of TSLP in the EMT process was unknown. We aimed to access whether TSLP could induce EMT in airway epithelia and its potential mechanism. Materials and Methods: Human bronchial epithelial (HBE) cells were incubated with TSLP or transforming growth factor beta 1 (TGF-ß1) or both. SB431542 was used to block TGF-ß1 signal while TSLP siRNA was used to performed TSLP knockdown. Changes in E-cadherin, vimentin, collagen I and fibronectin level were measured by real-time PCR, western blot and immunofluorescence staining. Expressions of TGF-ß after TSLP administration were measured by real-time PCR, western blot and ELISA. Results: TSLP induced changes of EMT relevant markers alone and promoted TGF-ß1-induced EMT in HBEs. Intracellular and extracellular expression of TGF-ß1 were upregulated by TSLP. SB431542 blocked changes of EMT relevant markers induced by TSLP. Knockdown of TSLP not only reduced TSLP and TGF-ß1 expression but also inhibited changes of EMT relevant markers induced by TGF-ß1 in HBEs. Conclusions: TSLP could induce early stage of EMT in airway epithelial cells through upregulation of TGF-ß1. This effect may act as a targeting point for suppression of asthma.
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Brônquios/metabolismo , Citocinas/metabolismo , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima/fisiologia , Remodelação das Vias Aéreas/fisiologia , Asma/metabolismo , Biomarcadores/metabolismo , Caderinas/metabolismo , Linhagem Celular , Colágeno Tipo I/metabolismo , Fibronectinas/metabolismo , Humanos , Vimentina/metabolismoRESUMO
Objective: Fibrocyte localization to the airways and thymic stromal lymphopoietin (TSLP) overexpression in the lung are features of severe asthma. The aim of this study was to determine whether TSLP contributes to fibrocyte trafficking and airway remodeling in a mouse model of allergic asthma. Methods: We established a chronic asthma animal model by administering house dust mite (HDM) extracts intranasally for up to 5 consecutive weeks. Mouse anti-TSLP monoclonal antibody (mAb) was given intraperitoneally starting the 4th week. Fluorescence-labeled CD34/collagen I (Col I)-dual-positive fibrocytes were examined by confocal microscopy. The level of TGF-ß1 in the bronchoalveolar lavage (BAL) fluid was determined by ELISA. Results: We found significantly increased levels of TSLP and TGF-ß1 in the lung of the mice subjected to repeated allergen exposure, which was accompanied by increased number of fibrocytes in the sub-epithelial zone and the BAL fluid. However, blocking TSLP markedly decreased the production of TGF-ß1, reduced the number of fibrocytes and subsequently prevented alterations of both airway and vascular structures. Conclusions: Our data suggested that TSLP might function in airway remodeling by promoting circulating fibrocyte recruitment to the lung in the mice subjected to chronic allergen exposure. These results provide a better rationale for targeting the interaction between TSLP and fibrocytes as a therapeutic approach for chronic allergic asthma.
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Remodelação das Vias Aéreas/fisiologia , Asma/fisiopatologia , Citocinas/biossíntese , Fator de Crescimento Transformador beta1/biossíntese , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Doença Crônica , Células do Tecido Conjuntivo , Modelos Animais de Doenças , Feminino , Pulmão/fisiopatologia , Camundongos , Camundongos Endogâmicos BALB C , Imagem Óptica , Pyroglyphidae/imunologia , Linfopoietina do Estroma do TimoRESUMO
A case of 3-hydroxyisobutyryl-CoA hydrolase deficiency was reported, and its clinical features, gene mutation characteristics, and diagnosis and treatment were analyzed with reference to related literature. The patient aged 1 year and 6 months had developmental regression and paroxysmal dystonia after pyrexia and diarrhea, and head MRI showed symmetrical lesions in the bilateral basal ganglia. No pathogenic mutation was found in the full-length detection of mitochondrial genome. Nuclear gene detection of mitochondrial-related diseases found new compound heterozygous mutations in the HIBCH gene, i.e., c.439-2A>G and c.958A>G (p.K320E), which were inherited from his father and mother, respectively. The boy was given cocktail therapy, dietary valine restriction, and symptomatic treatment. After 2 weeks of treatment, there were improvements in dystonia and motor and intellectual development.
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Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/terapia , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Erros Inatos do Metabolismo dos Aminoácidos/terapia , Tioléster Hidrolases/deficiência , Anormalidades Múltiplas/enzimologia , Anormalidades Múltiplas/genética , Erros Inatos do Metabolismo dos Aminoácidos/enzimologia , Erros Inatos do Metabolismo dos Aminoácidos/genética , Sequência de Bases , Humanos , Lactente , Masculino , Dados de Sequência Molecular , Mutação Puntual , Tioléster Hidrolases/genéticaRESUMO
Idiopathic pulmonary hemosiderosis (IPH) is an extremely rare cause of massive pulmonary hemorrhage in children. During the acute phase, death due to massive alveolar hemorrhage and subsequent severe respiratory failure. We report two cases of IPH children who developed hypoxemic respiratory failure and massive pulmonary hemorrhage. One case of a 10-year-old boy was treated with methylprednisolone pulse therapy (10mg/kg/d) for the first three days and followed by systemic steroid therapy, he successfully decannulated 10days later and discharged with a favorable quality of life. Another case of a 4year-old female child with Down's syndrome diagnosed as IPH for over one year and treated with oral corticosteroids for maintenance therapy. She sudden suffered severe hypoxemia with rapid falls in the hemoglobin level. We applied methylprednisolone pulse therapy (10mg/kg/d) for three days and other supportive therapies, the girl survived through complicated with oxygen dependence. We suggest that methylprednisolone pulse therapy provides a chance of recovery and survival for patients with IPH at the acute phase, even if accompanied by severe pulmonary hemorrhage.
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Glucocorticoides/administração & dosagem , Hemorragia/tratamento farmacológico , Hemossiderose/complicações , Pneumopatias/complicações , Metilprednisolona/administração & dosagem , Insuficiência Respiratória/tratamento farmacológico , Criança , Pré-Escolar , Síndrome de Down/complicações , Feminino , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Hemossiderose/diagnóstico por imagem , Humanos , Pneumopatias/diagnóstico por imagem , Pneumopatias/tratamento farmacológico , Pneumopatias/etiologia , Masculino , Radiografia Torácica , Insuficiência Respiratória/etiologia , Tomografia Computadorizada por Raios X , Hemossiderose PulmonarRESUMO
OBJECTIVE: To study the roles of PKCα on the proliferation, apoptosis, differentiation, cytokine production and inducible regulatory T cell (iTreg) induction of T cells. METHODS: T cells from WT (PKCαâº/âº) or PKCα knockout (PKCαâ»/â») mice were isolated and cultured in vitro. T cell proliferation and apoptosis were determined using ³H thymidine incorporation and CSFE/Annexin V staining. Cytokines production (IL-2, IL-4, IFN-γ and IL-17) was detected using ELISA. CD4âºT cells were isolated and cultured in vitro via Th17 or iTreg biased condition. Flow cytometry was used to detect the cell differentiation. RESULTS: The production of IL-2 upon TCR stimulation increased, while the contents of IL-4 and IL-17 decreased in the PKCαâ»/â» group compared with the PKCαâº/⺠group. The differentiation rate of Th17 cells decreased, while the iTreg production increased in the PKCαâ»/â» group compared with the PKCαâº/⺠group. CONCLUSIONS: PKC-α is proinflammatory.
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Proteína Quinase C-alfa/fisiologia , Linfócitos T/fisiologia , Animais , Diferenciação Celular , Citocinas/biossíntese , Ativação Linfocitária , Camundongos , Receptores de Antígenos de Linfócitos T/fisiologia , Células Th17/imunologiaRESUMO
The changes in the physicochemical properties and the anticancer activity of 10-Hydroxycamptothecin (HCPT) in the presence of Cucurbit (n = 7) uril(Q[7]) were studied by using UV absorption spectroscopy, fluorescence spectroscopy and phase solubility method. The results revealed that in the acid solution (pH 2), the absorption band of the guest HCPT exhibited a progressively lower absorbance at λ265 nm, while a progressively higher absorbance at λ425 nm as the ratio of N(Q[7])/N(HCPT) was increased. A sharp isosbestic point at λ387 nm was consistent with a simple interaction between Q[7] and HCPT. The emission spectra of the guest HCPT also exhibited a progressive decrease in fluorescence intensity at λ558 nm with a violet shift when the ratio of N(Q[7])/N(HCPT) was increased. The measured data from both absorption spectrophotometric and fluorescence spectroscopy analysis fitted to a 2 : 1 host:guest complexation, yielded a calculated stable constants (ß) of 1.549 x 10(13) L2 x mol(-2) and 0.907 x 10(13) L2 x mol(-2) respectively through Reactlab EQULLIBRIA software. The effect of Q[7] on the solubility of HCPT was investigated by using phase solubility method. Upon the addition of Q[7] concentration, the solubility of HCPT was enhanced step by step at the value of pH 2 and an about 250 times advance was attained when the concentration of Q[7] was 1 x 10(-3) mol x L(-1), while the Q[7]-HCPT inclusion complex made by total evaporation method can increase about 1 170 times compared to the pure HCPT. At the end, the mixtures of Q[7] and HCPT were tested in terms of cytotoxicity on the human lung cancer cell line A549 and human leukemia cell line K562 to compare their reactivity with the free HCPT and the comparative cytotoxic activity was got for A549 and K562.
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Antineoplásicos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/química , Camptotecina/análogos & derivados , Imidazóis/química , Camptotecina/farmacologia , Humanos , Células K562/efeitos dos fármacos , Solubilidade , Espectrometria de FluorescênciaRESUMO
OBJECTIVE: To study the extraction technology of epigoitri from Isatidis Radix by supercritical CO2 fluid. METHODS: The effects of pressure, temperature, time, concentration and dosage of alcohol were studied by single factor analysis and orthogonal test. RESULTS: The optimized conditions were as follows: The pressure was 20 MPs, the temperature was 50 degrees C, the time was 2 h, concentration of alcohol was 100%, dosage was 80 mL. The content of epigoitri in the extract could reach 38.63% under the above conditions. CONCLUSION: This method is simple, rapid and it is suitable for the extraction of epigoitri from Isatidis Radix.
Assuntos
Cromatografia com Fluido Supercrítico , Medicamentos de Ervas Chinesas/isolamento & purificação , Isatis/química , Oxazolidinonas/isolamento & purificação , Dióxido de Carbono , Raízes de Plantas/química , Pressão , Reprodutibilidade dos Testes , Solventes/química , Temperatura , Fatores de TempoRESUMO
Introduction: Bacterial metabolic environment influences antibiotic killing efficacy. Thus, a full understanding for the metabolic resistance mechanisms is especially important to combat antibiotic-resistant bacteria. Methods: Isobaric tags for relative and absolute quantification-based proteomics approach was employed to compare proteomes between ceftazidime-resistant and -sensitive Edwarsiella tarda LTB4 (LTB4-RCAZ and LTB4-S, respectively). Results: This analysis suggested the possibility that the ceftazidime resistance mediated by depressed glucose is implemented through an inefficient metabolic flux from glycolysis, the pyruvate cycle, glutamate metabolism to purine metabolism. The inefficient flux was demonstrated by the reduced expression of genes and the decreased activity of enzymes in the four metabolic pathways. However, supplement upstream glucose and downstream guanosine separately restored ceftazidime killing, which not only supports the conclusion that the inefficient metabolic flux is responsible for the resistance, but also provides an effective approach to reverse the resistance. In addition, the present study showed that ceftazidime is bound to pts promoter in E. tarda. Discussion: Our study highlights the way in fully understanding metabolic resistance mechanisms and establishing metabolites-based metabolic reprogramming to combat antibiotic resistance.
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BACKGROUND: Diabetic peripheral neuropathy causes significant pain to patients. Umbilical cord mesenchymal stem cells have been shown to be useful in the treatment of diabetes and its complications. The aim of this study was to investigate whether human umbilical cord mesenchymal stem cells treated with interferon-gamma can ameliorate nerve injury associated with diabetes better than human umbilical cord mesenchymal stem cells without interferon-gamma treatment. METHODS: Human umbilical cord mesenchymal stem cells were assessed for adipogenic differentiation, osteogenic differentiation, and proliferation ability. Vonfry and a hot disc pain tester were used to evaluate tactile sensation and thermal pain sensation in mice. Hematoxylin-eosin and TUNEL staining were performed to visualize sciatic nerve fiber lesions and Schwann cell apoptosis in diabetic mice. Western blotting was used to detect expression of the apoptosis-related proteins Bax, B-cell lymphoma-2, and caspase-3 in mouse sciatic nerve fibers and Schwann cells. Real-Time Quantitative PCR was used to detect mRNA levels of the C-X-C motif chemokine ligand 1, C-X-C motif chemokine ligand 2, C-X-C motif chemokine ligand 9, and C-X-C motif chemokine ligand 10 in mouse sciatic nerve fibers and Schwann cells. Enzyme-linked immunosorbent assay was used to detect levels of the inflammatory cytokines, interleukin-1ß, interleukin-6, and tumor necrosis factor-α in serum and Schwann cells. RESULTS: The adipogenic differentiation capacity, osteogenic differentiation capacity, and proliferation ability of human umbilical cord mesenchymal stem cells were enhanced after interferon-gamma treatment. Real-Time Quantitative PCR revealed that interferon-gamma promoted expression of the adipogenic markers, PPAR-γ and CEBP-α, as well as of the osteogenic markers secreted phosphoprotein 1, bone gamma-carboxyglutamate protein, collagen type I alpha1 chain, and Runt-related transcription factor 2. The results of hematoxylin-eosin and TUNEL staining showed that pathological nerve fiber damage and Schwann cell apoptosis were reduced after the injection of interferon-gamma-treated human umbilical cord mesenchymal stem cells. Expression of the apoptosis-related proteins, caspase-3 and Bax, was significantly reduced, while expression of the anti-apoptotic protein B-cell lymphoma-2 was significantly increased. mRNA levels of the cell chemokines, C-X-C motif chemokine ligand 1, C-X-C motif chemokine ligand 2, C-X-C motif chemokine ligand 9, and C-X-C motif chemokine ligand 10, were significantly reduced, and levels of the inflammatory cytokines, interleukin-1ß, interleukin-6, and tumor necrosis factor-α, were decreased. Tactile and thermal pain sensations were improved in diabetic mice. CONCLUSION: Interferon-gamma treatment of umbilical cord mesenchymal stem cells enhanced osteogenic differentiation, adipogenic differentiation, and proliferative potential. It can enhance the ability of human umbilical cord mesenchymal stem cells to alleviate damage to diabetic nerve fibers and Schwann cells, in addition to improving the neurological function of diabetic mice.
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Bats are reservoir hosts for many zoonotic viruses. Despite this, relatively little is known about the diversity and abundance of viruses within individual bats, and hence the frequency of virus co-infection and spillover among them. We characterize the mammal-associated viruses in 149 individual bats sampled from Yunnan province, China, using an unbiased meta-transcriptomics approach. This reveals a high frequency of virus co-infection (simultaneous infection of bat individuals by multiple viral species) and spillover among the animals studied, which may in turn facilitate virus recombination and reassortment. Of note, we identify five viral species that are likely to be pathogenic to humans or livestock, based on phylogenetic relatedness to known pathogens or in vitro receptor binding assays. This includes a novel recombinant SARS-like coronavirus that is closely related to both SARS-CoV and SARS-CoV-2. In vitro assays indicate that this recombinant virus can utilize the human ACE2 receptor such that it is likely to be of increased emergence risk. Our study highlights the common occurrence of co-infection and spillover of bat viruses and their implications for virus emergence.
Assuntos
COVID-19 , Quirópteros , Coinfecção , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Humanos , Filogenia , SARS-CoV-2 , Viroma , China/epidemiologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genéticaRESUMO
BACKGROUND: Extensive knowledge of allergic multimorbidities is required to improve the management of allergic diseases with the industrialization of China. However, the demography and allergen distribution patterns of allergic multimorbidities in China remain unclear, despite the increasing prevalence of allergies. METHODS: This was a real-world, cross-sectional study of 1273 outpatients diagnosed with one or more allergic diseases in Guangzhou, the most populated city of southern China, with leading industrial and commercial centers, between April 2021 and March 2022. Seven allergic diseases (allergic rhinitis (AR), asthma (AS)/cough variant asthma (CVA), atopic dermatitis (AD)/eczema, food allergy (FA), allergic conjunctivitis (AC), drug allergy (DA), and anaphylaxis) were assessed. Positive rates of sensitization to different allergens were measured using an allergen detection system of the UniCAP (Pharmacia Diagnostics, Sweden) instrument platform to compare the groups of allergic multimorbidities against a single entity. RESULTS: There were 659 (51.8%) males and 614 (48.2%) females aged from 4 months to 74 years included in the analysis. The study participants who were diagnosed with allergic diseases had an average of 1.6 diagnoses. Overall, 46.5% (592 of 1273) of the patients had more than one allergic condition, and allergic rhinitis was the most common type of multimorbidity. Women were more likely to suffer from an allergic disease alone, whereas allergic multimorbidities were more likely to be diagnosed in men (p = 0.005). In addition, allergic multimorbidities were common in all age groups, with an incidence ranging from 37.1% to 57.4%, in which children and adolescents were more frequently diagnosed with allergic multimorbidities than adults (18-60 years old) (all p < 0.05). Allergic multimorbidity was observed throughout the year. A difference in the positive rate of allergens sensitization and total immunoglobulin E (tIgE) levels between different allergic multimorbidities was observed. CONCLUSIONS: Allergic multimorbidities were very commonly found in nearly half of all patients with allergies. The proportion of allergic multimorbidities varied with the type of disease, sex, age, and allergen distribution pattern. These findings may help clinicians to develop "One health" strategies for the clinical management of allergic diseases.
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Escherichia coli endotoxin LPS regulates blood-brain barrier permeability by disrupting the tight junction (TJ) complex between brain endothelial cells. This study used Bend.3 cells to examine the signaling networks involved in the hyperpermeability of the brain endothelial barrier caused by LPS. The LPS-induced alterations in the brain endothelial barrier were associated with PKC (a, ß, ζ) and RhoA, but were independent of PI3K and the tyrosine kinase pathway. Inhibition of PKC (a, ß, ζ) and RhoA activity using shRNA and dominant negative mutants diminished the effects of LPS on the brain's endothelial TJs. The interactions between the PKC and Rho pathways were therefore examined. PKC-a and PKC-ζ, but not PKC-ß interacted with RhoA in Bend.3 cells stimulated by LPS. PKC-a acted as the upstream molecule for Rho and PKC-ζ acted as the downstream target for Rho. Comparing the effect of double inhibition of "Rho and PKC" and single inhibition of "Rho" or "PKC" confirmed that this interaction is critical for LPS-induced brain endothelial cell hyperpermeability. Collectively these data are the first to suggest that LPS affects the brain's endothelial TJ barrier via PKC (a, ß, ζ)- and RhoA, independent of the PI3K and tyrosine kinase pathways. In addition, PKC-a and PKC-ζ, respectively, act as the upstream and downstream regulator for RhoA in the process.
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Barreira Hematoencefálica/metabolismo , Endotoxinas/metabolismo , Proteína Quinase C/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Linhagem Celular , Endotélio/metabolismo , Camundongos , Permeabilidade , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/genética , RNA Interferente Pequeno/genética , Transdução de Sinais , Transfecção , Proteína rhoA de Ligação ao GTP/antagonistas & inibidores , Proteína rhoA de Ligação ao GTP/genéticaRESUMO
PURPOSE: The aim of this study was to investigate the signaling mechanisms surrounding changes in tight junction (TJ) and the permeability of human intestinal epithelial cell induced by tumor necrosis factor-alpha (TNF-α). METHODS: To confirm that TNF-α induces epithelial barrier hyperpermeability by disrupting tight junction, Caco-2 cells were exposed to TNF-α, and changes in epithelial permeability (via TER assay), F-actin dynamics (via Rhodamine-phalloidin staining) and tight junction protein expression (via western blot) were monitored. Moreover, to ensure that NF-κB participated in the regulatory mechanisms, Caco-2 cells were transfected with DNMu-IκBα or control plasmids, the above experiments were repeated and the activation effect of TNF-α on NF-κB was detected by luciferase reporter assays. Lastly, we took dominant negative plasmid and knockdown approaches to investigate the potential importance of the NF-κB/myosin light chain kinase (MLCK)/myosin light chain phosphorylation (pMLC) pathways in TNF-a-mediated damage. RESULT: TNF-α could cause NF-κB activation, F-actin rearrangement, tight junction disruption and barrier dysfunction. These effects were alleviated by inhibiting NF-κB. TNF-α induced increase of MLCK transcription and MLC phosphorylation act later than NF-κB activation, which could be suppressed both by inactivating and deleting NF-κB. CONCLUSIONS: TNF-α induces intestinal epithelial cell hyperpermeability by disrupting TJs, in part through MLCK upregulation, in which NF-κB is the positive upstream regulator for MLCK.
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Epitélio/efeitos dos fármacos , Epitélio/patologia , Intestinos/efeitos dos fármacos , Intestinos/patologia , Fator de Necrose Tumoral alfa/farmacologia , Actinas/metabolismo , Células CACO-2 , Permeabilidade da Membrana Celular/efeitos dos fármacos , Epitélio/metabolismo , Humanos , Proteínas I-kappa B/metabolismo , Mucosa Intestinal/metabolismo , Cadeias Leves de Miosina/metabolismo , Quinase de Cadeia Leve de Miosina/genética , Quinase de Cadeia Leve de Miosina/metabolismo , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Plasmídeos/metabolismo , RNA Interferente Pequeno/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Fator de Transcrição RelA/metabolismo , Transcrição Gênica/efeitos dos fármacosRESUMO
Bats are reservoir hosts for many zoonotic viruses. Despite this, relatively little is known about the diversity and abundance of viruses within bats at the level of individual animals, and hence the frequency of virus co-infection and inter-species transmission. Using an unbiased meta-transcriptomics approach we characterised the mammalian associated viruses present in 149 individual bats sampled from Yunnan province, China. This revealed a high frequency of virus co-infection and species spillover among the animals studied, with 12 viruses shared among different bat species, which in turn facilitates virus recombination and reassortment. Of note, we identified five viral species that are likely to be pathogenic to humans or livestock, including a novel recombinant SARS-like coronavirus that is closely related to both SARS-CoV-2 and SARS-CoV, with only five amino acid differences between its receptor-binding domain sequence and that of the earliest sequences of SARS-CoV-2. Functional analysis predicts that this recombinant coronavirus can utilize the human ACE2 receptor such that it is likely to be of high zoonotic risk. Our study highlights the common occurrence of inter-species transmission and co-infection of bat viruses, as well as their implications for virus emergence.
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OBJECTIVE: To study the influence of lipopolysaccharide (LPS) on the permeability of rat brain microvascular endothelial cells (BMECs) and possible molecular mechanism. METHODS: Monolayers of primary rat BMECs were separated and cultured, and then treated with (LPS group) or without LPS (control group). The barrier integrity was measured by transendothelial electrical resistance (TEER) assay. The degrees of RhoA activation were determined by Pull-down assay. The expression levels of p115RhoGEF, zonula occludens-1 (ZO-1), occludin and claudin-5 proteins were detected by Western blot analysis. RESULTS: The average TEER values of rat BMECs in the LPS group were 108.3±4.2 Ωâ¢cm2 and 85.4±2.5 Ωâ¢cm2 respectively 3 and 12 hrs after LPS treatment, which were significantly lower than that in the control group (159.0±8.6 Ωâ¢cm2). Compared with the control group, the activity of RhoA started to increase 5 minutes after LPS treatment, and the expression of p115RhoGEF protein started to increase 1 hr after LPS treatment and the cellular protein levels of ZO-1, occludin and claudin-5 decreased significantly 3 hrs after LPS treatment in the LPS group (P<0.05). CONCLUSIONS: LPS may activate the p115RhoGEF/RhoA pathway and decrease protein expression of ZO-1, occludin and claudin-5, resulting in an increased permeability of rat BMECs.
Assuntos
Encéfalo/irrigação sanguínea , Permeabilidade Capilar/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Animais , Impedância Elétrica , Células Endoteliais/metabolismo , Fatores de Troca do Nucleotídeo Guanina/análise , Ratos , Ratos Sprague-Dawley , Fatores de Troca de Nucleotídeo Guanina Rho , Junções Íntimas/química , Proteína rhoA de Ligação ao GTP/análiseRESUMO
BACKGROUND: Capillary leak syndrome (CLS) is a rare disease characterized by profound vascular leakage and presents as a classic triad of hypotension, hypoalbuminemia and hemoconcentration. Severe CLS is mostly induced by sepsis and generally life-threatening in newborns, especially in premature infants. Continuous renal replacement therapy (CRRT) plays an important role of supportive treatment for severe CLS. Unfortunately, CRRT in preterm infants has rarely been well defined. CASE PRESENTATION: We report the case of a 11-day-old girl with CLS caused by sepsis, who was delivered by spontaneous vaginal delivery (SVD) at gestational age of 25 weeks and 4 days, and a birth weight of 0.89 Kilograms(kg). The infant received powerful management consisting of united antibiotics, mechanical ventilation, intravenous albumin and hydroxyethyl starch infusion, vasoactive agents, small doses of glucocorticoids and other supportive treatments. However, the condition rapidly worsened with systemic edema, hypotension, pulmonary exudation, hypoxemia and anuria in about 40 h. Finally, we made great efforts to perform CRRT for her. Fortunately, the condition improved after 82 h' CRRT, and the newborn was rescued and gradually recovered. CONCLUSION: CRRT is an effective rescue therapeutic option for severe CLS and can be successfully applied even in extremely-low-birth-weight premature.