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BACKGROUND: Most international treatment guidelines recommend rapid initiation of antiretroviral therapy (ART) for people newly diagnosed with human immunodeficiency virus (HIV)-1 infection, but experiences with rapid ART initiation remain limited in China. We aimed to evaluate the efficacy and safety of efavirenz (400 mg) plus lamivudine and tenofovir disoproxil fumarate (EFV + 3TC + TDF) versus coformulated bictegravir, emtricitabine, and tenofovir alafenamide (BIC/FTC/TAF) in rapid ART initiation among men who have sex with men (MSM) who have been diagnosed with HIV. METHODS: This multicenter, open-label, randomized clinical trial enrolled MSM aged ≥18 years to start ART within 14 days of confirmed HIV diagnosis. The participants were randomly assigned in a 1:1 ratio to receive EFV (400 mg) + 3TC + TDF or BIC/FTC/TAF. The primary end point was viral suppression (<50â copies/mL) at 48 weeks per US Food and Drug Administration Snapshot analysis. RESULTS: Between March 2021 and July 2022, 300 participants were enrolled; 154 were assigned to receive EFV + 3TC + TDF (EFV group) and 146 BIC/FTC/TAF (BIC group). At week 48, 118 (79.2%) and 140 (95.9%) participants in the EFV and BIC group, respectively, were retained in care with viral suppression, and 24 (16.1%) and 1 (0.7%) participant in the EFV and BIC group (P < .001), respectively, discontinued treatment because of adverse effects, death, or lost to follow-up. The median increase of CD4 count was 181 and 223â cells/µL (P = .020), respectively, for the EFV and BIC group, at week 48. The overall incidence of adverse effects was significantly higher for the EFV group (65.8% vs 37.7%, P < .001). CONCLUSIONS: BIC/FTC/TAF was more efficacious and safer than EFV (400 mg) + 3TC + TDF for rapid ART initiation among HIV-positive MSM in China.
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Alcinos , Fármacos Anti-HIV , Benzoxazinas , Ciclopropanos , Emtricitabina , Infecções por HIV , Homossexualidade Masculina , Lamivudina , Tenofovir , Humanos , Masculino , Infecções por HIV/tratamento farmacológico , Adulto , Tenofovir/uso terapêutico , Tenofovir/análogos & derivados , China , Emtricitabina/uso terapêutico , Emtricitabina/administração & dosagem , Ciclopropanos/uso terapêutico , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/administração & dosagem , Alcinos/uso terapêutico , Lamivudina/uso terapêutico , Lamivudina/administração & dosagem , Lamivudina/efeitos adversos , Benzoxazinas/uso terapêutico , Alanina/uso terapêutico , Pessoa de Meia-Idade , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Compostos Heterocíclicos de 4 ou mais Anéis/efeitos adversos , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Contagem de Linfócito CD4 , Dioxolanos/uso terapêutico , Dioxolanos/administração & dosagem , Compostos Heterocíclicos com 3 Anéis/uso terapêutico , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Compostos Heterocíclicos com 3 Anéis/administração & dosagem , Piperazinas/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Carga Viral , Adulto Jovem , Combinação de Medicamentos , HIV-1/efeitos dos fármacos , Amidas , PiridonasRESUMO
The high affinity interaction between P-selectin glycoprotein ligand-1 (PSGL-1) and P-selectin is mediated by a multimotif glycosulfopeptide (GSP) recognition domain consisting of clustered tyrosine sulfates and a Core 2 O-glycan terminated with sialyl LewisX (C2-O-sLeX). These distinct GSP motifs are much more common than previously appreciated within a wide variety of functionally important domains involved in protein-protein interactions. However, despite the potential of GSPs to serve as tools for fundamental studies and prospects for drug discovery, their utility has been limited by the absence of chemical schemes for synthesis on scale. Herein, we report the total synthesis of GSnP-6, an analogue of the N-terminal domain of PSGL-1, and potent inhibitor of P-selectin. An efficient, scalable, hydrogenolysis-free synthesis of C2-O-sLeX-Thr-COOH was identified by both convergent and orthogonal one-pot assembly, which afforded this crucial building block, ready for direct use in solid phase peptide synthesis (SPPS). C2-O-sLeX-Thr-COOH was synthesized in 10 steps with an overall yield of 23% from the 4-O,5-N oxazolidinone thiosialoside donor. This synthesis represents an 80-fold improvement in reaction yield as compared to prior reports, achieving the first gram scale synthesis of SPPS ready C2-O-sLeX-Thr-COOH and enabling the scalable synthesis of GSnP-6 for preclinical evaluation. Significantly, we established that GSnP-6 displays dose-dependent inhibition of venous thrombosis in vivo and inhibits vaso-occlusive events in a human sickle cell disease equivalent microvasculature-on-a-chip system. The insights gained in formulating this design strategy can be broadly applied to the synthesis of a wide variety of biologically important oligosaccharides and O-glycan bearing glycopeptides.
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Glicopeptídeos , Glicoproteínas de Membrana , Selectina-P , Glicopeptídeos/síntese química , Glicopeptídeos/química , Glicopeptídeos/farmacologia , Selectina-P/antagonistas & inibidores , Selectina-P/metabolismo , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/metabolismo , Humanos , Animais , CamundongosRESUMO
IgA nephropathy (IgAN), which has been confirmed as a complement mediated autoimmune disease, is also one form of glomerulonephritis associated with COVID-19. Here, we aim to investigate the clinical and immunological characteristics of patients with IgAN after COVID-19. The level of plasma level of C5a (p < 0.001), soluble C5b-9 (p = 0.018), FHR5 (p < 0.001) were all significantly higher in Group CoV (33 patients with renal biopsy-proven IgAN experienced COVID-19) compared with Group non-CoV (44 patients with IgAN without COVID-19), respectively. Compared with Group non-CoV, the intensity of glomerular C4d (p = 0.017) and MAC deposition (p < 0.001) and Gd-IgA1 deposition (p = 0.005) were much stronger in Group CoV. Our finding revealed that for IgAN after COVID-19, mucosal immune responses to SARS-CoV-2 infection may result in the overactivation of systemic and renal local complement system, and increased glomerular deposition of Gd-IgA1, which may lead to renal dysfunction and promote renal progression in IgAN patients.
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COVID-19 , Glomerulonefrite por IGA , SARS-CoV-2 , Humanos , Glomerulonefrite por IGA/imunologia , Glomerulonefrite por IGA/sangue , COVID-19/imunologia , COVID-19/complicações , Feminino , Masculino , Adulto , SARS-CoV-2/imunologia , Pessoa de Meia-Idade , Ativação do Complemento/imunologia , Proteínas do Sistema Complemento/imunologia , Proteínas do Sistema Complemento/metabolismo , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Glomérulos Renais/patologia , Glomérulos Renais/imunologia , Complemento C5a/imunologia , Complemento C5a/metabolismoRESUMO
Current therapy for hepatic injury induced by the accumulation of bile acids is limited. Leucine-rich repeat G protein-coupled receptor 4 (LGR4), also known as GPR48, is critical for cytoprotection and cell proliferation. Here, we reported a novel function for the LGR4 in cholestatic liver injury. In the bile duct ligation (BDL)-induced liver injury model, hepatic LGR4 expression was significantly downregulated. Deficiency of LGR4 in hepatocytes (Lgr4LKO) notably decreased BDL-induced liver injury measured by hepatic necrosis, fibrosis, and circulating liver enzymes and total bilirubin. Levels of total bile acids in plasma and liver were markedly reduced in these mice. However, deficiency of LGR4 in macrophages (Lyz2-Lgr4MKO) demonstrated no significant effect on liver injury induced by BDL. Deficiency of LGR4 in hepatocytes significantly attenuated S1PR2 and the phosphorylation of protein kinase B (AKT) induced by BDL. Recombinant Rspo1 and Rspo3 potentiated the taurocholic acid (TCA)-induced upregulation in S1PR2 and phosphorylation of AKT in hepatocytes. Inhibition of S1PR2-AKT signaling by specific AKT or S1PR2 inhibitors blocked the increase of bile acid secretion induced by Rspo1/3 in hepatocytes. Our studies indicate that the R-spondins (Rspos)-LGR4 signaling in hepatocytes aggravates the cholestatic liver injury by potentiating the production of bile acids in a S1PR2-AKT-dependent manner.NEW & NOTEWORTHY Deficiency of LGR4 in hepatocytes alleviates BDL-induced liver injury. LGR4 in macrophages demonstrates no effect on BDL-induced liver injury. Rspos-LGR4 increases bile acid synthesis and transport via potentiating S1PR2-AKT signaling in hepatocytes.
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Doença Hepática Crônica Induzida por Substâncias e Drogas , Colestase , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fígado/metabolismo , Colestase/complicações , Colestase/metabolismo , Hepatócitos/metabolismo , Ácidos e Sais Biliares/metabolismo , Ductos Biliares/metabolismo , Ligadura , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismoRESUMO
BACKGROUND: Interpregnancy interval (IPI) is associated with a variety of adverse maternal and infant outcomes. However, reports of its associations with early infant neurodevelopment are limited and the mechanisms of this association have not been elucidated. Maternal-fetal glucose metabolism has been shown to be associated with infant neurodevelopmental. The objective of this study was to determine whether this metabolism plays a role in the relationship between IPI and neurodevelopment. METHODS: This prospective birth cohort study included 2599 mother-infant pairs. The IPI was calculated by subtracting the gestational age of the current pregnancy from the interval at the end of the previous pregnancy. Neurodevelopmental outcomes at 12 months in infants were assessed by the Ages and Stages Questionnaire Edition 3 (ASQ-3). Maternal fasting venous blood was collected at 24-28 weeks and cord blood was collected at delivery. The association between IPI and neurodevelopment was determined by logistic regression. Mediation and sensitivity analyses were also conducted. RESULTS: In our cohort, 14.0% had an IPI < 12 months. IPI < 12 months increased the failure of the communication domain, fine motor domain, and personal social domain of the ASQ (relative risks (RRs) with 95% confidence interval (CI): 1.73 [1.11,2.70]; 1.73 [1.10,2.72]; 1.51 [1.00,2.29]). Maternal homeostasis model assessment of insulin resistance (HOMA-IR) and cord blood C-peptide was significantly associated with failure in the communication domain [RRs with 95% CI: 1.15 (1.02, 1.31); 2.15 (1.26, 3.67)]. The proportion of the association between IPI and failure of the communication domain risk mediated by maternal HOMA-IR and cord blood C-peptide was 14.4%. CONCLUSIONS: IPI < 12 months was associated with failing the communication domain in infants. Maternal-fetal glucose metabolism abnormality may partially explain the risk of neurodevelopmental delay caused by short IPI.
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Nascimento Prematuro , Gravidez , Lactente , Feminino , Humanos , Estudos de Coortes , Nascimento Prematuro/etiologia , Intervalo entre Nascimentos , Peptídeo C , Estudos Prospectivos , GlucoseRESUMO
OBJECTIVE: The objective of this study was to gain insight into the barriers hindering the use of pre-exposure prophylaxis (PrEP) among men who have sex with men (MSM) in five cities in China. METHODS: MSM were recruited via community-based organizations in an online "snowball" manner. Participants completed the questionnaire anonymously and shared it with key MSM peers (seeds) in five cities in China. Based on the results of univariate analysis, we used a structural equation model to analyse the role of PrEP knowledge awareness, PrEP counselling, and other behavioural variables on PrEP use. RESULTS: The study collected a total of 4223 valid questionnaires, and 18.2% of participants reported PrEP use. The results of the standardized total effects showed that the following paths were statistically significant (p < 0.05): from the age of first sex with men to PrEP knowledge awareness (ß = -0.113) and PrEP use (ß = 0.042); from high-risk sexual behaviour scores to PrEP counselling (ß = 0.039) and PrEP use (ß = 0.103); from the number of HIV tests in the last year to PrEP knowledge awareness (ß = 0.034), PrEP counselling (ß = 0.170), and PrEP use (ß = 0.197); from the level of self-perceived risk of HIV infection to PrEP counselling (ß = -0.115); from PrEP knowledge awareness to PrEP use (ß = -0.049); and from PrEP counselling to PrEP use (ß = 0.420). CONCLUSIONS: The proportion of PrEP use among MSM was relatively low. Age at first sex with men, number of HIV tests, high-risk sexual behaviour, and PrEP counselling had a positive effect on PrEP use, whereas PrEP knowledge awareness had an inverse effect on PrEP use.
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Polysaccharopeptide (PSP) is a potential active component in traditional Chinese medicine because of its anticancer effects on a variety of cancer cells and as immune enhancers of the immune system. Previous studies on the role of PSP in breast cancer have been limited, and the mechanism has not been clarified. This study is based on network pharmacology and molecular docking technology to predict the possible target of PSP treatment of breast cancer, and use experiments to verify the effect and mechanism of PSP on breast cancer. In this study, 287 PSP targets were obtained using SwissTargetPrediction database and PharmMapper database, and 183 breast cancer targets were obtained using DisGenNET database. By intersections of PSP targets and breast cancer targets, a total of 10 intersections were obtained. GO functional enrichment, KEGG pathway enrichment and molecular docking of these 10 target genes were performed to obtain the potential targets of PSP on breast cancer. In vitro experiments, we found that PSP significantly inhibited the proliferation and induced apoptosis of breast cancer cell lines MDA-MB-231, SUM-159 and MCF-7. Western Blot results showed that PSP could down-regulate the expression of p-JAK2 and p-STAT3 proteins. Similarly, the results of in vivo experiments showed that PSP can directly inhibit the tumor of MDA-MB-231 tumor-bearing mice, and the mechanism of action is mainly to inhibit the JAK2-STAT3 pathway. The above results were consistent with the results of network pharmacology, which provides a scientific basis for the clinical application of PSP in breast cancer patients.
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Apoptose , Neoplasias da Mama , Proliferação de Células , Janus Quinase 2 , Simulação de Acoplamento Molecular , Farmacologia em Rede , Fator de Transcrição STAT3 , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Feminino , Animais , Camundongos , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Linhagem Celular Tumoral , Janus Quinase 2/metabolismo , Proteoglicanas/farmacologia , Células MCF-7 , Camundongos Nus , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacosRESUMO
We describe the synthesis of a benzoyl-based C2-O-sLeX-Thr-COOH building block devoid of any aglycone transfer or orthoester-formed byproducts. The absence of byproducts was achieved in the course of both [1 + 1] glycosylation reactions with thiophenol aglycone containing galactose acceptors, as well as a [2 + 2] glycosylation in the presence of a p-methoxy benzyl containing glucosamine-fucose disaccharide. We also report an efficient [2 + 1 + 1] synthesis of a peracetylated sLeX en route to a peracetylated C2-O-sLeX-Thr-COOH. While the total synthesis of the latter compound was recently reported by a related route, the divergent [2 + 1 + 1] synthesis provided good reaction yields for each step of the sequence, establishing this scheme as an alternate approach to the peracetylated C2-O-sLeX-Thr-COOH. Importantly, the current report details the role of a variety of hydroxy-protecting groups, including acetyl, benzoyl, p-methoxy benzyl, and naphthylmethyl that may be considered in designing a route to this complex Core 2 glycan. While we have previously described the use of more glycosylation-friendly naphthylmethyl protecting groups, the current synthesis used p-methoxy benzyl protecting groups with excellent reaction yields, demonstrating the feasibility of applying this side reaction-prone protecting group for this challenging synthesis.
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Polissacarídeos , Polissacarídeos/química , Polissacarídeos/síntese química , Glicosilação , Estrutura MolecularRESUMO
Influenza viruses are susceptible to seasonal influenza, which has repeatedly caused global pandemics and jeopardized human health. Vaccines are only used as preventive medicine due to the extreme mutability of influenza viruses, and antiviral medication is the most significant clinical treatment to reduce influenza morbidity and mortality. Nevertheless, the clinical application of anti-influenza virus agents is characterized by the narrow therapeutic time window, the susceptibility to drug resistance, and relatively limited effect on severe influenza. Therefore, it is of great significance to develop novel anti-influenza virus drugs to fulfill the urgent clinical needs. Influenza viruses enter host cells through the hemagglutinin (HA) mediated membrane fusion process, and fusion inhibitors function antivirally by blocking hemagglutinin deformation, promising better therapeutic efficacy and resolving drug resistance, with targets different from marketed medicines. Previous studies have shown that unnatural peptides derived from Human Immunodeficiency Virus Type 1 (HIV-1) membrane fusion proteins exhibit anti-HIV-1 activity. Based on the similarity of the membrane fusion protein deformation process between HIV-1 and H1N1, we selected sequences derived from the gp41 subunit in the HIV-1 fusion protein, and then constructed N-trimer spatial structure through inter-helical isopeptide bond modification, to design the novel anti-H1N1 fusion inhibitors. The results showed that the novel peptides could block 6-HB formation during H1N1 membrane fusion procedure, and thus possessed significant anti-H1N1 activity, comparable to the positive control oseltamivir. Our study demonstrates the design viability of peptide fusion inhibitors based on similar membrane fusion processes among viruses, and furthermore provides an important idea for the novel anti-H1N1 inhibitors development.
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Antivirais , Vírus da Influenza A Subtipo H1N1 , Peptídeos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Antivirais/síntese química , Humanos , Peptídeos/química , Peptídeos/farmacologia , Peptídeos/síntese química , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Células Madin Darby de Rim Canino , Cães , Relação Dose-Resposta a Droga , Animais , Estrutura Molecular , Sequência de AminoácidosRESUMO
Cadmium (Cd) is a toxic heavy metal that causes nephrosis, including acute kidney injury. To prevent and treat acute kidney injury (AKI) following Cd exposure, a tripeptide, Ser-Arg-Pro (SRP), from Sipunculus nudus L. was employed, and its potential efficacy in AKI was assessed. Oral administration of SRP significantly alleviated Cd-induced kidney damage, leading to improved renal function and the attenuation of structural abnormalities. A network pharmacology analysis revealed the potential of SRP in renal protection by targeting various pathways, including mitogen-activated protein kinase (MAPK) signaling, inflammatory response, and apoptosis pathways. Mechanistic studies indicated that SRP achieves renal protection by inhibiting the activation of MAPK pathways (phosphorylation of p38, p56, ERK, and JNK) in the oxidative stress cascade, suppressing inflammatory responses (iNOS, Arg1, Cox2, TNF-α, IL-1ß, and IL-6), and restoring altered apoptosis factors (caspase-9, caspase-3, Bax, and Bcl-2). Hence, SRP has the potential to be used as a therapeutic agent for the treatment of Cd-induced nephrotoxicity.
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Injúria Renal Aguda , Apoptose , Cádmio , Oligopeptídeos , Estresse Oxidativo , Animais , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/induzido quimicamente , Apoptose/efeitos dos fármacos , Camundongos , Cádmio/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Masculino , Oligopeptídeos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Inflamação/tratamento farmacológico , Modelos Animais de Doenças , Farmacologia em RedeRESUMO
BACKGROUND: Antiretroviral therapy (ART) can reduce viral load in individuals infected with human immunodeficiency virus (HIV); however, some HIV-infected individuals still cannot achieve optimal immune recovery even after ART. Hence, we described the profile of peripheral immune cells and explored the association with disease progression in patients infected with HIV-1. METHODS: Mass cytometry analysis was used to characterize the circulating immune cells of 20 treatment-naïve (TNs), 20 immunological non-responders (INRs), 20 immunological responders (IRs), and 10 healthy controls (HCs). Correlation analysis was conducted between cell subpopulation percentages and indicators including HIV-1 cell-associated (CA)-RNA, DNA, CD4+ T cell count, and CD4/CD8 ratio. RESULTS: Global activation, immunosenescence, and exhaustion phenotypes were observed in myeloid cells and T cells from individuals with HIV-1 infection. We also found that specific subsets or clusters of myeloid, CD4+ T, and CD8+ T cells were significantly lost or increased in TN individuals, which could be partially restored after receiving ART. The percentages of several subpopulations correlated with HIV-1 CA-RNA, DNA, CD4+ T cell count, and CD4/CD8 ratio, suggesting that changes in immune cell composition were associated with therapeutic efficacy. CONCLUSION: These data provide a complete profile of immune cell subpopulations or clusters that are associated with disease progression during chronic HIV-1 infection, which will improve understanding regarding the mechanism of incomplete immune recovery in INRs.
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Infecções por HIV , HIV-1 , Humanos , Linfócitos T CD8-Positivos , RNA , Progressão da Doença , DNA , Linfócitos T CD4-Positivos , Carga Viral , Contagem de Linfócito CD4RESUMO
For randomly degraded products undergoing a two-stage degradation process, traditional random effects models assume that the degradation rate follows a symmetrically normal distribution. However, certain products exhibit asymmetric degradation rates. In light of this, this paper proposes an approach for reliability analysis based on the inverse Gaussian (IG) degeneration process, which considers both asymmetric random effects and the two-stage nature simultaneously. To begin with, we establish a two-stage IG degradation process model that incorporates a skew normal random effect. Subsequently, we determine the location of change points using the Schwarz Information Criterion (SIC). The estimation of parameters is then conducted by combining Maximum Likelihood Estimations (MLEs) with the Genetic Algorithm (GA). Finally, we validate and demonstrate the practicality for the proposed model through Monte Carlo (MC) simulation and examples involving lithium batteries.
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Warfarin-related nephropathy (WRN) is defined as acute kidney injury subsequent to excessive anticoagulation with warfarin. Patients with mechanical prosthetic valves require long-term anticoagulant therapy. Nonetheless, warfarin remains the sole available option for anticoagulant therapy. Consequently, patients with mechanical prosthetic valves constitute a special group among the entire anticoagulant population. The present study recorded two cases of patients who had undergone mechanical prosthetic valve surgery and were receiving warfarin therapy. They presented to the hospital with gross hematuria and progressive creatinine levels. Notably, their international normalized ratio (INR) did not exceed three. Subsequent renal biopsies confirmed WRN with IgA nephropathy. The two patients continued to receive warfarin as anticoagulation therapy and were prescribed oral corticosteroids and cyclophosphamide, which resulted in improved renal function during the follow-up. Based on a review of all relevant literature and the present study, we proposed a new challenge: must elevated INR levels be one of the criteria for clinical diagnosis of WRN? Perhaps some inspiration can be drawn from the present article.
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Anticoagulantes , Varfarina , Humanos , Varfarina/efeitos adversos , Anticoagulantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Feminino , Coeficiente Internacional Normatizado , Idoso , Glomerulonefrite por IGA , Biópsia , Injúria Renal Aguda/induzido quimicamente , Rim/patologia , Rim/efeitos dos fármacos , Ciclofosfamida/efeitos adversos , Corticosteroides/uso terapêutico , Corticosteroides/efeitos adversos , Corticosteroides/administração & dosagemRESUMO
As the basis of musical emotions, dynamic tension experience is felt by listeners as music unfolds over time. The effects of musical harmonic and melodic structures on tension have been widely investigated, however, the potential roles of metrical structures in tension perception remain largely unexplored. This experiment examined how different metrical structures affect tension experience and explored the underlying neural activities. The electroencephalogram (EEG) was recorded and subjective tension was rated simultaneously while participants listened to music meter sequences. On large time scale of whole meter sequences, it was found that different overall tension and low-frequency (1 ~ 4 Hz) steady-state evoked potentials were elicited by metrical structures with different periods of strong beats, and the higher overall tension was associated with metrical structure with the shorter intervals between strong beats. On small time scale of measures, dynamic tension fluctuations within measures was found to be associated with the periodic modulations of high-frequency (10 ~ 25 Hz) neural activities. The comparisons between the same beats within measures and across different meters both on small and large time scales verified the contextual effects of meter on tension induced by beats. Our findings suggest that the overall tension is determined by temporal intervals between strong beats, and the dynamic tension experience may arise from cognitive processing of hierarchical temporal expectation and attention, which are discussed under the theoretical frameworks of metrical hierarchy, musical expectation and dynamic attention.
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Patients with diabetes coexisting with viral infection tend to have poor outcomes, but the association between diabetes and coronavirus disease 2019 (COVID-19) prognosis is controversial at present. The present study reviewed and analyzed the data of 1,892 patients with COVID-19 admitted to Shaanxi Provincial People's Hospital (Xi'an, China). Demographic, clinical, laboratory and treatment data as well as clinical outcomes were extracted from the electronic medical records and compared between patients with and without diabetes. Multivariate logistic regression analysis was used to determine the risk factors affecting the prognosis of COVID-19. Compared with patients without diabetes, the levels of glucose, C-reactive protein, procalcitonin, creatinine, total bilirubin and plasma D-dimer were significantly increased in patients with diabetes, while the levels of lymphocytes and albumin were significantly decreased (P<0.05). Multivariate logistic regression analysis revealed that platelet count, albumin, total bilirubin and lymphocytes were significantly correlated with the severity of COVID-19. Diabetes mellitus was an independent prognostic factor that affected the mortality outcome of patients with COVID-19. Additionally, an age of ≥80 years, male sex, cerebral infarction complications and a critical diagnosis of COVID-19 at admission were risk factors for critical illness during hospitalization. The results of the present study suggest that diabetes may be a risk factor for the rapid progression and poor prognosis of COVID-19. Therefore, further attention should be paid to individuals with diabetes in order to prevent rapid deterioration.
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System-level fault diagnosis model, namely, the PMC model, detects fault nodes only through the mutual testing of nodes in the system without physical equipment. In order to achieve server nodes fault diagnosis in large-scale data center networks (DCNs), the traditional algorithm based on the PMC model cannot meet the characteristics of high diagnosability, high accuracy and high efficiency due to its inability to ensure that the test nodes are fault-free. This paper first proposed a fault-tolerant Hamiltonian cycle fault diagnosis (FHFD) algorithm, which tests nodes in the order of the Hamiltonian cycle to ensure that the test nodes are faultless. In order to improve testing efficiency, a hierarchical diagnosis mechanism was further proposed, which recursively divides high scale structures into a large number of low scale structures based on the recursive structure characteristics of DCNs. Additionally, we proved that $ 2(n-2){n^{k-1}} $ and $ (n-2){t_{n, k}}/{t_{n, 1}} $ faulty nodes could be detected for $ BCub{e_{n, k}} $ and $ DCel{l_{n, k}} $ within a limited time for the proposed diagnosis strategy. Simulation experiments have also shown that our proposed strategy has improved the diagnosability and test efficiency dramatically.
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BACKGROUND: Nur77 belongs to the member of orphan nuclear receptor 4A family that plays critical roles in maintaining vascular homeostasis. This study aims to determine whether Nur77 plays a role in attenuating vascular dysfunction, and if so, to determine the molecular mechanisms involved. METHODS: Both Nur77 knockout (Nur77 KO) and Nur77 endothelial specific transgenic mice (Nur77-Tg) were employed to examine the functional significance of Nur77 in vascular endothelium in vivo. Endothelium-dependent vasodilatation to acetylcholine (Ach) and reactive oxygen species (ROS) production was determined under inflammatory and high glucose conditions. Expression of genes was determined by real-time PCR and western blot analysis. RESULTS: In response to tumor necrosis factor alpha (TNF-α) treatment and diabetes, the endothelium-dependent vasodilatation to Ach was significantly impaired in aorta from Nur77 KO as compared with those from the wild-type (WT) mice. Endothelial specific overexpression of Nur77 markedly prevented both TNF-α- and high glucose-induced endothelial dysfunction. Compared with WT mice, after TNF-α and high glucose treatment, ROS production in aorta was significantly increased in Nur77 KO mice, but it was inhibited in Nur77-Tg mice, as determined by dihydroethidium (DHE) staining. Furthermore, we demonstrated that Nur77 overexpression substantially increased the expression of several key enzymes involved in nitric oxide (NO) production and ROS scavenging, including endothelial nitric oxide synthase (eNOS), guanosine triphosphate cyclohydrolase 1 (GCH-1), glutathione peroxidase-1 (GPx-1), and superoxide dismutases (SODs). Mechanistically, we found that Nur77 increased GCH1 mRNA stability by inhibiting the expression of microRNA-133a, while Nur77 upregulated SOD1 expression through directly binding to the human SOD1 promoter in vascular endothelial cells. CONCLUSION: Our results suggest that Nur77 plays an essential role in attenuating endothelial dysfunction through activating NO production and anti-oxidant pathways in vascular endothelium. Targeted activation of Nur77 may provide a novel therapeutic approach for the treatment of cardiovascular diseases associated with endothelial dysfunction.
Assuntos
Antioxidantes , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Doenças Vasculares , Animais , Humanos , Camundongos , Antioxidantes/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Glucose/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase-1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismoRESUMO
Shear failure often occurs in engineering rock mass (such as inclined pillar) in gently inclined strata. Prediction and characterization the orientation of shear failure plane is the foundation of rock mass engineering reinforcement. In this paper, sandstone samples are used to perform uniaxial and shear tests to obtain the basic mechanical parameters. Then, by employing the numerical method, the combined compression-shear loading tests were carried out for inclined specimens varied from 0° to 25° at an interval of 5°, to obtain the dip effect on the orientation of rock failure plane. The results show that the failure plane of rock changes with the change of dip angle of rock sample. Based on the Mohr-Coulomb criterion, the ultimate stress state of rock was characterized under combined compression-shear loading. The ultimate strength of rock is equal to the ratio of the stress circle radius of rock under combined compression-shear condition to the stress circle radius of rock under uniaxial compression condition, multiplied by the uniaxial compressive strength. The fracture angle of rock was defined under combined compression-shear loading. A theoretical model was developed for predicting the fracture angle. The developed model could be characterized by internal friction angle, dip angle of rock sample and Poisson's ratio. Finally, the numerical results of the fracture angle were analyzed, which are consistent with the predicted results of the model. The investigation shows that the rock fracture angle has a dip effect, which decreases with the increase of the inclination angle of the sample. The research results provide a new means to identify the potential failure plane of engineering rock mass, and lay a theoretical foundation for calculating the orientation of rock fracture plane.
RESUMO
Spalling failure is a typical failure phenomenon after excavation and unloading of a deep, hard brittle rock mass, which seriously threatens the safe construction of deep roadways (tunnels) and other projects. From the engineering viewpoint, it is essential to accurately evaluate the range and depth of surrounding rock spalling failure. From the perspective of the laboratory and engineering site, the strength and formation mechanism of hard rock spalling failure were statistically summarized and analyzed. Under uniaxial and low confining pressure conditions, when the load reached the rock damage stress, cracks in the rock penetrated to form a failure plane approximately parallel to the axial loading direction, and the strength of rock mass spalling was much smaller than that of intact rock spalling. A triaxial compression test was conducted to analyze the dilatation axial strain and dilatation lateral strain characteristics of gneiss. The results showed that dilatation axial strain gradually increased with the increase of confining pressure, whereas dilatation lateral strain was almost unchanged. Therefore, a safety factor (FS) based on dilatation lateral strain was developed. Through comparison with other strain-based spalling criteria, the establishment and physical meaning of the method were described in detail. In addition, FS was applied to analyze the deep roadway of the Hongtoushan Copper Mine in China and the Rm415 test tunnel in Canada. The results showed that the spalling criterion could accurately indicate the range and depth of the surrounding rock spalling failure, which verified the rationality and applicability of the new spalling criterion. Thus, FS can be utilized as a new theory and analysis tool for the assessment and prevention of spalling failure in deep hard rock roadways.