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1.
J Virol ; 98(4): e0013924, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38501663

RESUMO

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a novel porcine enteric coronavirus, and the broad interspecies infection of SADS-CoV poses a potential threat to human health. This study provides experimental evidence to dissect the roles of distinct domains within the SADS-CoV spike S1 subunit in cellular entry. Specifically, we expressed the S1 and its subdomains, S1A and S1B. Cell binding and invasion inhibition assays revealed a preference for the S1B subdomain in binding to the receptors on the cell surface, and this unknown receptor is not utilized by the porcine epidemic diarrhea virus. Nanoparticle display demonstrated hemagglutination of erythrocytes from pigs, humans, and mice, linking the S1A subdomain to the binding of sialic acid (Sia) involved in virus attachment. We successfully rescued GFP-labeled SADS-CoV (rSADS-GFP) from a recombinant cDNA clone to track viral infection. Antisera raised against S1, S1A, or S1B contained highly potent neutralizing antibodies, with anti-S1B showing better efficiency in neutralizing rSADS-GFP infection compared to anti-S1A. Furthermore, depletion of heparan sulfate (HS) by heparinase treatment or pre-incubation of rSADS-GFP with HS or constituent monosaccharides could inhibit SADS-CoV entry. Finally, we demonstrated that active furin cleavage of S glycoprotein and the presence of type II transmembrane serine protease (TMPRSS2) are essential for SADS-CoV infection. These combined observations suggest that the wide cell tropism of SADS-CoV may be related to the distribution of Sia or HS on the cell surface, whereas the S1B contains the main protein receptor binding site. Specific host proteases also play important roles in facilitating SADS-CoV entry.IMPORTANCESwine acute diarrhea syndrome coronavirus (SADS-CoV) is a novel pathogen infecting piglet, and its unique genetic evolution characteristics and broad species tropism suggest the potential for cross-species transmission. The virus enters cells through its spike (S) glycoprotein. In this study, we identify the receptor binding domain on the C-terminal part of the S1 subunit (S1B) of SADS-CoV, whereas the sugar-binding domain located at the S1 N-terminal part of S1 (S1A). Sialic acid, heparan sulfate, and specific host proteases play essential roles in viral attachment and entry. The dissection of SADS-CoV S1 subunit's functional domains and identification of cellular entry cofactors will help to explore the receptors used by SADS-CoV, which may contribute to exploring the mechanisms behind cross-species transmission and host tropism.


Assuntos
Alphacoronavirus , Infecções por Coronavirus , Glicoproteína da Espícula de Coronavírus , Animais , Humanos , Camundongos , Alphacoronavirus/química , Alphacoronavirus/fisiologia , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Heparitina Sulfato , Ácido N-Acetilneuramínico/metabolismo , Peptídeo Hidrolases , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Suínos
2.
Brain ; 147(5): 1710-1725, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38146639

RESUMO

Mitochondrial dysfunction is an early pathological feature of Alzheimer disease and plays a crucial role in the development and progression of Alzheimer's disease. Strategies to rescue mitochondrial function and cognition remain to be explored. Cyclophilin D (CypD), the peptidylprolyl isomerase F (PPIase), is a key component in opening the mitochondrial membrane permeability transition pore, leading to mitochondrial dysfunction and cell death. Blocking membrane permeability transition pore opening by inhibiting CypD activity is a promising therapeutic approach for Alzheimer's disease. However, there is currently no effective CypD inhibitor for Alzheimer's disease, with previous candidates demonstrating high toxicity, poor ability to cross the blood-brain barrier, compromised biocompatibility and low selectivity. Here, we report a new class of non-toxic and biocompatible CypD inhibitor, ebselen, using a conventional PPIase assay to screen a library of ∼2000 FDA-approved drugs with crystallographic analysis of the CypD-ebselen crystal structure (PDB code: 8EJX). More importantly, we assessed the effects of genetic and pharmacological blockade of CypD on Alzheimer's disease mitochondrial and glycolytic bioenergetics in Alzheimer's disease-derived mitochondrial cybrid cells, an ex vivo human sporadic Alzheimer's disease mitochondrial model, and on synaptic function, inflammatory response and learning and memory in Alzheimer's disease mouse models. Inhibition of CypD by ebselen protects against sporadic Alzheimer's disease- and amyloid-ß-induced mitochondrial and glycolytic perturbation, synaptic and cognitive dysfunction, together with suppressing neuroinflammation in the brain of Alzheimer's disease mouse models, which is linked to CypD-related membrane permeability transition pore formation. Thus, CypD inhibitors have the potential to slow the progression of neurodegenerative diseases, including Alzheimer's disease, by boosting mitochondrial bioenergetics and improving synaptic and cognitive function.


Assuntos
Doença de Alzheimer , Isoindóis , Mitocôndrias , Compostos Organosselênicos , Peptidil-Prolil Isomerase F , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptidil-Prolil Isomerase F/metabolismo , Animais , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Camundongos , Humanos , Cognição/efeitos dos fármacos , Azóis/farmacologia , Azóis/uso terapêutico , Ciclofilinas/metabolismo , Ciclofilinas/antagonistas & inibidores , Camundongos Transgênicos , Camundongos Endogâmicos C57BL , Masculino , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico
3.
Dev Biol ; 494: 26-34, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36470449

RESUMO

The human respiratory system, consisting of the airway and alveoli, is one of the most complex organs directly interfaced with the external environment. The diverse epithelial cells lining the surface are usually the first cell barrier that comes into contact with pathogens that could lead to deadly pulmonary disease. There is an urgent need to understand the mechanisms of self-renewal and protection of these epithelial cells against harmful pathogens, such as SARS-CoV-2. Traditional models, including cell lines and mouse models, have extremely limited native phenotypic features. Therefore, in recent years, to mimic the complexity of the lung, airway and alveoli organoid technology has been developed and widely applied. TGF-ß/BMP/SMAD, FGF and Wnt/ß-catenin signaling have been proven to play a key role in lung organoid expansion and differentiation. Thus, we summarize the current novel lung organoid culture strategies and discuss their application for understanding the lung biological features and pathophysiology of pulmonary diseases, especially COVID-19. Lung organoids provide an excellent in vitro model and research platform.


Assuntos
COVID-19 , Camundongos , Animais , Humanos , COVID-19/metabolismo , SARS-CoV-2 , Pulmão , Organoides/metabolismo , Biologia
4.
J Biol Chem ; 299(5): 104668, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37011862

RESUMO

Inhibition of heat shock protein 90 (Hsp90), a prominent molecular chaperone, effectively limits severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection but little is known about any interaction between Hsp90 and SARS-CoV-2 proteins. Here, we systematically analyzed the effects of the chaperone isoforms Hsp90α and Hsp90ß on individual SARS-CoV-2 viral proteins. Five SARS-CoV-2 proteins, namely nucleocapsid (N), membrane (M), and accessory proteins Orf3, Orf7a, and Orf7b were found to be novel clients of Hsp90ß in particular. Pharmacological inhibition of Hsp90 with 17-DMAG results in N protein proteasome-dependent degradation. Hsp90 depletion-induced N protein degradation is independent of CHIP, a ubiquitin E3 ligase previously identified for Hsp90 client proteins, but alleviated by FBXO10, an E3 ligase identified by subsequent siRNA screening. We also provide evidence that Hsp90 depletion may suppress SARS-CoV-2 assembly partially through induced M or N degradation. Additionally, we found that GSDMD-mediated pyroptotic cell death triggered by SARS-CoV-2 was mitigated by inhibition of Hsp90. These findings collectively highlight a beneficial role for targeting of Hsp90 during SARS-CoV-2 infection, directly inhibiting virion production and reducing inflammatory injury by preventing the pyroptosis that contributes to severe SARS-CoV-2 disease.


Assuntos
COVID-19 , Proteínas de Choque Térmico HSP90 , Piroptose , SARS-CoV-2 , Vírion , Humanos , COVID-19/patologia , COVID-19/fisiopatologia , COVID-19/virologia , Proteínas de Choque Térmico HSP90/metabolismo , SARS-CoV-2/química , SARS-CoV-2/crescimento & desenvolvimento , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Ubiquitina-Proteína Ligases/metabolismo , Vírion/química , Vírion/crescimento & desenvolvimento , Vírion/metabolismo , Proteínas Virais/metabolismo
5.
Mol Biol Evol ; 40(1)2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36625089

RESUMO

Determining the functional consequences of karyotypic changes is invariably challenging because evolution tends to obscure many of its own footprints, such as accumulated mutations, recombination events, and demographic perturbations. Here, we describe the assembly of a chromosome-level reference genome of the gayal (Bos frontalis) thereby revealing the structure, at base-pair-level resolution, of a telo/acrocentric-to-telo/acrocentric Robertsonian translocation (2;28) (T/A-to-T/A rob[2;28]). The absence of any reduction in the recombination rate or genetic introgression within the fusion region of gayal served to challenge the long-standing view of a role for fusion-induced meiotic dysfunction in speciation. The disproportionate increase noted in the distant interactions across pro-chr2 and pro-chr28, and the change in open-chromatin accessibility following rob(2;28), may, however, have led to the various gene expression irregularities observed in the gayal. Indeed, we found that many muscle-related genes, located synthetically on pro-chr2 and pro-chr28, exhibited significant changes in expression. This, combined with genome-scale structural variants and expression alterations in genes involved in myofibril composition, may have driven the rapid sarcomere adaptation of gayal to its rugged mountain habitat. Our findings not only suggest that large-scale chromosomal changes can lead to alterations in genome-level expression, thereby promoting both adaptation and speciation, but also illuminate novel avenues for studying the relationship between karyotype evolution and speciation.


Assuntos
Cromatina , Genoma , Animais , Bovinos
6.
BMC Cancer ; 23(1): 1139, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996814

RESUMO

BACKGROUND: Calcification is a common phenomenon in both benign and malignant thyroid nodules. However, the clinical significance of calcification remains unclear. Therefore, we explored a more objective method for distinguishing between benign and malignant thyroid calcified nodules. METHODS: This retrospective study, conducted at two centers, involved a total of 631 thyroid nodules, all of which were pathologically confirmed. Ultrasound image sets were employed for analysis. The primary evaluation index was the area under the receiver-operator characteristic curve (AUROC). We compared the diagnostic performance of deep learning (DL) methods with that of radiologists and determined whether DL could enhance the diagnostic capabilities of radiologists. RESULTS: The Xception classification model exhibited the highest performance, achieving an AUROC of up to 0.970, followed by the DenseNet169 model, which attained an AUROC of up to 0.959. Notably, both DL models outperformed radiologists (P < 0.05). The success of the Xception model can be attributed to its incorporation of deep separable convolution, which effectively reduces the model's parameter count. This feature enables the model to capture features more effectively during the feature extraction process, resulting in superior performance, particularly when dealing with limited data. CONCLUSIONS: This study conclusively demonstrated that DL outperformed radiologists in differentiating between benign and malignant calcified thyroid nodules. Additionally, the diagnostic capabilities of radiologists could be enhanced with the aid of DL.


Assuntos
Calcinose , Aprendizado Profundo , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/diagnóstico por imagem , Estudos Retrospectivos , Curva ROC , Calcinose/diagnóstico por imagem , Ultrassonografia/métodos
7.
Ann Hematol ; 102(1): 55-62, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36385651

RESUMO

Comparing the characteristics of thrombotic thrombocytopenic purpura (TTP) and TTP-like syndrome patients at admission will allow early differentiation of TTP from TTP-like syndrome and help tailor initial treatment. The medical records of 78 patients with suspected TTP in the Emergency Department of Peking University People's Hospital in the past 5 years were retrospectively analyzed and divided into TTP and TTP-like syndrome groups based on ADAMTS13 activity and ADAMTS13 antibody titer. There were 25 and 53 patients in the TTP group and the TTP-like syndrome group, respectively. The neutrophil-to-lymphocyte ratio (P = 0.025) was tremendously higher, and albumin (P = 0.002) was lower in the TTP-like syndrome group, indicating a more severe inflammation. Compared with the TTP-like syndrome group, the TTP group had an approximately two-fold to three-fold higher prevalence of central nervous system dysfunction (P < 0.001). Also, hemolysis was more substantial in the TTP group as evidenced by higher schistocytes (P < 0.001), reticulocyte (P < 0.001), total bilirubin (P = 0.002), indirect bilirubin (P < 0.001), lactate dehydrogenase (P = 0.007) and cell-free hemoglobin (P < 0.001), simultaneously lower platelet (P < 0.001), haptoglobin (P = 0.044), and ADAMTS13 activity (P < 0.001). The Kaplan-Meier survival analysis showed that the TTP group significantly predicted poor prognosis (log-rank test: X2 = 5.368, P = 0.021). TTP and TTP-like syndrome are two kinds of distinct phenotypes with different hemolysis statuses and illustrated differentiated inflammatory reactions, target organ damage (TOD), and the clinical outcome.


Assuntos
Hematologia , Púrpura Trombocitopênica Trombótica , Humanos , Proteína ADAMTS13 , Plaquetas , Hemólise , Púrpura Trombocitopênica Trombótica/diagnóstico , Púrpura Trombocitopênica Trombótica/epidemiologia , Estudos Retrospectivos , Síndrome
8.
J Org Chem ; 88(13): 7998-8009, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37279456

RESUMO

An unexpected Ugi cascade reaction was developed for the facile construction of γ-lactam-fused pyridone derivatives with high tolerance of substrates. A C(sp3)-N bond and a C(sp2)-C(sp2) bond were formed together, accompanied by a chromone ring-opening in Ugi adducts, under the basic conditions without any metal catalyst for the whole process. Screening data of several difficult-to-inhibit cancer cell lines demonstrated that 7l displayed a high cytotoxicity against HCT116 cells (IC50 = 5.59 ± 0.78 µM). Taken together, our findings revealed new insights into the molecular mechanisms underlying compound 7l and provided potential usage of this scaffold for cancer therapeutics.


Assuntos
Compostos Heterocíclicos , Lactamas , Lactamas/farmacologia , Piridonas/farmacologia , Piridonas/química , Metais
9.
Popul Health Metr ; 21(1): 5, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37143047

RESUMO

BACKGROUND: Measurement of the Chinese burden of disease with disability-adjusted life-years (DALYs) requires disability weight (DW) that quantify health losses for all non-fatal consequences of disease and injury. The Global Burden of Disease (GBD) 2013 DW study indicates that it is limited by lack of geographic variation in DW data and by the current measurement methodology. We aim to estimate DW for a set of health states from major diseases in the Wuhan population. METHODS: We conducted the DW measurement study for 206 health states through a household survey with computer-assisted face-to-face interviews and a web-based survey. Based on GBD 2013 DW study, paired comparison (PC) and Population health equivalence (PHE) method was used and different PC/PHE questions were randomly assigned to each respondent. In statistical analysis, the PC data was analyzed by probit regression. The probit regression results will be anchored by results from the PHE data analyzed by interval regression on the DW scale units between 0 (no loss of health) and 1 (loss equivalent to death). RESULTS: A total of 2610 and 3140 individuals were included in the household and web-based survey, respectively. The results from the total pooled data showed health state "mild anemia" (DW = 0.005, 95% UI 0.000-0.027) or "allergic rhinitis (hay fever)" (0.005, 95% UI 0.000-0.029) had the lowest DW and "heroin and other opioid dependence, severe" had the highest DW (0.699, 95% UI 0.579-0.827). A high correlation coefficient (Pearson's r = 0.876; P < 0.001) for DWs of same health states was observed between Wuhan's survey and GBD 2013 DW survey. Health states referred to mental symptom, fatigue, and the residual category of other physical symptoms were statistically significantly associated with a lower Wuhan's DWs than the GBD's DWs. Health states with disfigurement and substance use symptom had a higher DW in Wuhan population than the GBD 2013 study. CONCLUSIONS: This set of DWs could be used to calculate local diseases burden for health policy-decision in Wuhan population. The DW differences between the GBD's survey and Wuhan's survey suggest that there might be some contextual or culture factors influencing assessment on the severity of diseases.


Assuntos
Pessoas com Deficiência , Humanos , Carga Global da Doença , Saúde Global , China/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida
10.
J Biopharm Stat ; : 1-22, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37853747

RESUMO

This paper discusses the problem of disease prevalence in clinical studies, focusing on multiple comparisons based on stratified partially validated series in the presence of a gold standard. Five test statistics, including two Wald-type test statistics, the inverse hyperbolic tangent transformation test statistic, likelihood ratio test statistic, and score test statistic, are proposed to conduct multiple comparisons. To control the overall type I error rate, several adjustment procedures are developed, namely the Bonferroni, Single-step adjusted MaxT, Single-step adjusted MinP, Holm's Step-down, and Hochberg's step-up procedures, based on these test statistics. The performance of the proposed methods is evaluated through simulation studies in terms of the empirical type I error rate and empirical power. Simulation results show that the Single-step adjusted MaxT procedure and Single-step adjusted MinP procedure generally outperform the other three procedures, and these two test procedures based on all test statistics have satisfactory performance. Notably, the Single-step adjusted MinP procedure tends to exhibit higher empirical power than the Single-step adjusted MaxT procedure. Furthermore, the Step-down and Step-up procedures show greater power compared to the Bonferroni method. The study also observes that as the validated ratio increases, the empirical type I errors of all test procedures approach the nominal level while maintaining higher power. Two real examples are presented to illustrate the proposed methods.

11.
Pharm Stat ; 22(3): 418-439, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36524672

RESUMO

Data on the Likert scale are ubiquitous in medical research, including randomized trials. Statistical analysis of such data may be conducted using the means of raw scores or the rank information of the scores. In the context of parallel-group randomized trials, we quantify treatment effects by the probability that a subject in the treatment group has a better score than (or a win over) a subject in the control group. Asymptotic parametric and nonparametric confidence intervals for this win probability and associated sample size formulas are derived for studies with only follow-up scores, and those with both baseline and follow-up measurements. We assessed the performance of both the parametric and nonparametric approaches using simulation studies based on real studies with Likert item and Likert scale data. The simulation results demonstrate that even without baseline adjustment, the parametric methods did not perform well, in terms of bias, interval coverage percentage, balance of tail error, and assurance of achieving a pre-specified precision. In contrast, the nonparametric approach performed very well for both the unadjusted and adjusted win probability. We illustrate the methods with two examples: one using Likert item data and the other using Like scale data. We conclude that non-parametric methods are preferable for two-group randomization trials with Likert data. Illustrative SAS code for the nonparametric approach using existing procedures is provided.


Assuntos
Tamanho da Amostra , Humanos , Intervalos de Confiança , Estatísticas não Paramétricas , Ensaios Clínicos Controlados Aleatórios como Assunto , Probabilidade
12.
Cleft Palate Craniofac J ; 60(4): 446-453, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-34918551

RESUMO

The common cold and/or an associated fever during pregnancy have/has been suspected to harm the developing fetus. We sought possible correlations between a maternal common cold or fever during pregnancy and the risk of orofacial clefts in the offspring.We systematically searched PubMed and Embase using appropriate keywords, and we checked the reference lists of retrieved articles. We used random-effects models to estimate overall relative risks.Incidence of orofacial clefts.We included 13 case-control studies. Modest but statistically significant associations were found between a maternal common cold and cleft lip with or without a cleft palate (CL/CP) (odds ratio [OR] 2.17; 95% confidence interval [CI] 1.66-2.83) and a cleft palate only (CPO) (OR 3.08; 95% CI 1.5-6.34). Furthermore, maternal fever was also associated with an increased risk of CL/CP (OR 1.91, 95% CI 1.3-2.8) and CPO (OR 1.48, 95% CI 0.83-2.63) in the offspring. Further analyses of maternal influenza (alone) yielded similar results.Although evidence of heterogeneity should be carefully evaluated, our findings suggest that maternal common cold or fever during pregnancy may be associated with a greater risk of CL/CP or CPO in the offspring. Future cohort studies using valid assessments of maternal common cold exposure during pregnancy that consider the severity of fever are needed to clarify the contribution of maternal common cold or fever status to the risk of orofacial clefts in children.


Assuntos
Fenda Labial , Fissura Palatina , Resfriado Comum , Feminino , Gravidez , Criança , Humanos , Fenda Labial/complicações , Fissura Palatina/complicações , Resfriado Comum/complicações , Fatores de Risco , Estudos de Casos e Controles
13.
J Virol ; 95(24): e0111821, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34549985

RESUMO

Determination of the mechanisms of interspecies transmission is of great significance for the prevention of epidemic diseases caused by emerging coronaviruses (CoVs). Recently, porcine deltacoronavirus (PDCoV) was shown to exhibit broad host cell range mediated by surface expression of aminopeptidase N (APN), and humans have been reported to be at risk of PDCoV infection. In the present study, we first demonstrated overexpression of APN orthologues from various species, including mice and felines, in the APN-deficient swine small intestine epithelial cells permitted PDCoV infection, confirming that APN broadly facilitates PDCoV cellular entry and perhaps subsequent interspecies transmission. PDCoV was able to limitedly infect mice in vivo, distributing mainly in enteric and lymphoid tissues, suggesting that mice may serve as a susceptible reservoir of PDCoV. Furthermore, elements (two glycosylation sites and four aromatic amino acids) on the surface of domain B (S1B) of the PDCoV spike glycoprotein S1 subunit were identified to be critical for cellular surface binding of APN orthologues. However, both domain A (S1A) and domain B (S1B) were able to elicit potent neutralizing antibodies against PDCoV infection. The antibodies against S1A inhibited the hemagglutination activity of PDCoV using erythrocytes from various species, which might account for the neutralizing capacity of S1A antibodies partially through a blockage of sialic acid binding. The study reveals the tremendous potential of PDCoV for interspecies transmission and the role of two major PDCoV S1 domains in receptor binding and neutralization, providing a theoretical basis for development of intervention strategies. IMPORTANCE Coronaviruses exhibit a tendency for recombination and mutation, which enables them to quickly adapt to various novel hosts. Previously, orthologues of aminopeptidase N (APN) from mammalian and avian species were found to be associated with porcine deltacoronavirus (PDCoV) cellular entry in vitro. Here, we provide in vivo evidence that mice are susceptible to PDCoV limited infection. We also show that two major domains (S1A and S1B) of the PDCoV spike glycoprotein involved in APN receptor binding can elicit neutralizing antibodies, identifying two glycosylation sites and four aromatic amino acids on the surface of the S1B domain critical for APN binding and demonstrating that the neutralization activity of S1A antibodies is partially attributed to blockage of sugar binding activity. Our findings further implicate PDCoV's great potential for interspecies transmission, and the data of receptor binding and neutralization may provide a basis for development of future intervention strategies.


Assuntos
Antígenos CD13/biossíntese , Deltacoronavirus/metabolismo , Intestino Delgado/metabolismo , Proteínas Virais/química , Animais , COVID-19/virologia , Gatos , Chlorocebus aethiops , Cricetinae , Eritrócitos/metabolismo , Glicosilação , Células HEK293 , Humanos , Camundongos , Mutação , Ácido N-Acetilneuramínico/química , Células NIH 3T3 , Ligação Proteica , Domínios Proteicos , Risco , SARS-CoV-2 , Suínos , Doenças dos Suínos/virologia , Células Vero
14.
Glob Chang Biol ; 28(6): 2041-2052, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34935251

RESUMO

Direct measuring of CO2  flux remains challenging for global lakes. The traditional sampling and gas transfer models used to estimate lake CO2  fluxes are variable and uncertain, and ice-covered periods are often excluded from the annual carbon budget. Here, the first longtime (2013-2017) direct measurement of CO2  flux by eddy covariance system over the largest saline lake (Qinghai lake) in the Qinghai-Tibet Plateau (QTP) revealed that ice-covered period draws large amounts of CO2 from the atmosphere (-0.87 ± 0.38 g C m-2 d-1 ), a value more than twice the CO2  flux rate during the ice-free period (-0.41 ± 0.35 g C m-2 d-1 ). The total CO2 uptake by all saline lakes on the QTP was estimated to -10.28 ± 1.65 Tg C yr-1 , an equivalent to approximately one third of the net terrestrial ecosystems carbon sink in QTP. Our results indicate large sink for CO2 in winter is controlled by both seasonal hydrochemistry processes and lake ice absorption in saline lakes. This research also demonstrates decreasing CO2 uptake from the atmosphere by saline lakes on the QTP, which may turn carbon sinks to carbon sources with future warming.


Assuntos
Dióxido de Carbono , Lagos , Dióxido de Carbono/análise , Ecossistema , Estações do Ano , Tibet
15.
Immunol Invest ; 51(3): 465-479, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33140671

RESUMO

BACKGROUND: Osteoporosis is a common metabolic bone disease with high prevalence. Tetrandrine (TET) suppressed osteoclastogenesis, while the roles of TET in osteoporosis regulation remained unclear. Thus, the study aimed to investigate the effect of TET on osteoporosis and the underlying mechanism. METHODS: The osteoporosis rabbit model was established through anterior cruciate ligament transection (ACLT) and bilateral ovariectomy (OVX). The degeneration of articular cartilage was assessed using HE staining and Alcian blue staining. The liver and kidney tissue injury was determined using HE staining. The activity of osteoclasts was evaluated using Tartrate-resistant acid phosphatase (TRAP) staining. The changes in bone structural parameters were determined through measuring the BMD, BV/TV, Tb.Th, Tb.N, and Tb.Sp, and the serum levels of calcium and phosphorus. Macrophage polarization was determined using Flow cytometry. RESULTS: The bone structural parameters including BMD, BV/TV, Tb.N, Tb.Th and Tb.Sp were changed in osteoporosis rabbit, which was reversed by TET. Besides, TET suppressed the increased serum levels of calcium and phosphorus in osteoporosis rabbit. Furthermore, TET inhibited the degeneration of articular cartilage and the activity of osteoclasts induced by osteoporosis. Moreover, TET inhibited the levels of MMP-9, PPAR-γ, RANKL, ß-CTX and TRACP-5b, and increased the levels of OPG, ALP and osteocalcin (OC) in osteoporosis. Additionally, TET promoted macrophage transformation from M1 to M2 in osteoporotic and inhibited the production of IL-1ß, TNF-α, and IL-6. TET also inhibited the p65 phosphorylation in osteoporosis. Besides, TET reversed RANKL-induced osteoclasts proliferation, p65 phosphorylation, and the expression changes of RANKL, Ki67, PPAR-γ, ALP, OPG. CONCLUSION: TET attenuated bone structural parameters including BMD, BV/TV, Tb.N, Tb.Th and Tb.Sp, inhibited articular cartilage degeneration, promoted bone formation, inhibited the inflammatory response, and promoted macrophage transformation from M1 to M2 via NF-κB inactivation in osteoporosis. TET may be a promising drug for osteoporosis therapy. ABBREVIATION: TET: Tetrandrine; ACLT: anterior cruciate ligament transection; OVX: ovariectomy; TRAP: Tartrate-resistant acid phosphatase; BMD: bone mineral density; BV/TV: Bone volume/total volume; Tb.Th: trabecular thickness; Tb.N: trabecular number; Tb.Sp: trabecular separation; MMP-9: Matrix metallopeptidase 9; PPAR-γ: Peroxisome proliferator-activated receptor gamma; RANKL: Receptor activator of nuclear factor kappa-B ligand; OPG: Osteoprotegerin; ALP: alkaline phosphatase; OC: osteocalcin; ß-CTX: ß isomer of C-terminal telopeptide of type I collagen; TRACP-5b: Tartrate-resistant acid phosphatase 5b; TNF-α: tumor necrosis factor-α; IL-1ß: interleukin-1ß; IL-6: interleukin 6; NF-κB: Nuclear factor kappa B; PKC-α: Protein kinase C alpha; qRT-PCR: Quantitative real-time polymerase chain reaction.


Assuntos
Osteoclastos , Osteoporose , Animais , Benzilisoquinolinas , Cartilagem/metabolismo , Cartilagem/patologia , Proliferação de Células , Feminino , Humanos , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/metabolismo , Ovariectomia , Fosforilação , Ligante RANK , Coelhos
16.
BMC Cardiovasc Disord ; 22(1): 373, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35971091

RESUMO

BACKGROUND: Myocardial infarction (MI) is characterized by coronary artery occlusion, ischemia and hypoxia of myocardial cells, leading to irreversible myocardial damage. Therefore, it is urgent to explore the potential mechanism of myocardial injury during the MI process to develop effective therapies for myocardial cell rescue. METHODS: We downloaded the GSE71906 dataset from GEO DataSets, and the R software was used to identify the differentially expressed genes (DEGs) in mouse heart tissues of MI and sham controls. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were performed to understand the significantly activated signaling pathways in MI. Protein-protein interaction (PPI) network was constructed to highlight the hub genes in DEGs. The Western Blot, qRT-PCR and TUNEL staining were used to explore the function of hub gene in hypoxia-induced cardiomyocytes in vitro. RESULTS: A total of 235 DEGs were identified in GSE71906 dataset. Functional enrichment analysis revealed that the upregulated genes were primarily associated with the inflammatory response and apoptosis. 20 hub genes were identified in PPI network, and the early growth response 2 (EGR2) was highlighted. In vitro. We confirmed the EGR2 was upregulated induced by hypoxia and revealed the upregulated EGR2 aggravates pro-inflammation and pro-apoptotic genes expression. In addition, EGR2 knockout mitigates hypoxia-induced inflammation and apoptosis in cardiomyocytes. CONCLUSION: The present study identified the EGR2 was a hub gene in myocardial damage during MI process, the excessive EGR2 aggravates hypoxia-induced myocardial damage by accelerating inflammation and apoptosis in vitro. Therefore, targeting EGR2 offers a potential pharmacological strategy for myocardial cell rescue in MI.


Assuntos
Proteína 2 de Resposta de Crescimento Precoce , Infarto do Miocárdio , Miócitos Cardíacos , Animais , Apoptose , Biologia Computacional , Proteína 2 de Resposta de Crescimento Precoce/genética , Proteína 2 de Resposta de Crescimento Precoce/metabolismo , Hipóxia/metabolismo , Inflamação/metabolismo , Camundongos , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo
17.
J Biopharm Stat ; 32(6): 871-896, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-35536693

RESUMO

This article investigates the confidence interval (CI) construction of proportion difference for two independent partially validated series under the double-sampling scheme in which both classifiers are fallible. Several CIs based on the variance estimates recovery method of combining confidence limits from asymptotic, bootstrap, and Bayesian methods for two independent binomial proportions are developed under two models. Simulation results show that all CIs except for the bootstrap percentile-t CI and Bayesian credible interval with uniform prior under the independence model and all CIs under the dependence model generally perform well and are recommended. Two examples are used to illustrate the methodologies.


Assuntos
Modelos Estatísticos , Humanos , Teorema de Bayes , Intervalos de Confiança , Simulação por Computador
18.
Neoplasma ; 69(3): 657-669, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35293765

RESUMO

Colorectal cancer (CRC) is a common malignant tumor with high morbidity and mortality, and significant heterogeneity among patients. In this study, we aimed to explore the role and mechanism of CLK2 in CRC, a kinase that phosphorylates SR proteins involved in splicing. Based on the analysis from The Cancer Genome Atlas (TCGA) dataset and tissue microarray, we found that CLK2 was upregulated in CRC tissues and associated with a higher tumor stage and poorer overall survival. Consistent with the bioinformatics analysis, the functional experiments validated that CLK2 acted as a tumor-promoting factor in CRC progression. CLK2 knockdown suppressed aggressive cell proliferation, migration, and invasion in vitro, as well as restrained tumor growth in vivo. In terms of mechanism, we found that the Wnt/ß-catenin signaling pathway was responsible for the CLK2-induced CRC progression, based on the results of pathway enrichment analysis and subsequent experimental validation. Thus, our study, for the first time, identified the role of CLK2 in CRC development and provided a compelling biomarker for targeted therapy in CRC treatment.


Assuntos
Neoplasias Colorretais , Proteínas Serina-Treonina Quinases , Proteínas Tirosina Quinases , Via de Sinalização Wnt , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Centers for Disease Control and Prevention, U.S. , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/genética , Estados Unidos , Via de Sinalização Wnt/genética , beta Catenina/metabolismo
19.
Eur J Cancer Care (Engl) ; 31(6): e13688, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35971281

RESUMO

OBJECTIVE: Nurses' palliative care practice ability is the key to evaluating the quality of palliative care. This study aimed to identify the current situation of palliative care practices, competence and difficulties among nurses and determine whether difficulties play a mediating role between practices and competence. METHODS: A cross-sectional study was conducted. The online survey comprised demographics, the Palliative Care Self-Reported Practices Scale, the Palliative Care Nursing Self-competence Scale and the Palliative Care Difficulties Scale. Data were analysed by using descriptive statistics, univariate analysis, linear regression and mediation analysis. RESULTS: A total of 284 questionnaires were included for statistical analysis. The mean scores for practices, competence and difficulties were 67.81 (SD = 13.60), 124.28 (41.21) and 44.32 (12.68), respectively. There was a correlation between practices, competence and difficulties (p < 0.01). Competence and difficulties were independent predictors of practices (R2 adj  = 0.384, p < 0.001). Furthermore, difficulties mediated the relationship between practices and competence (b = 0.052, 95% confidence interval: 0.008-0.155). CONCLUSIONS: Continuous efforts should be made to enhance nurses' practices, competence and problem-solving abilities in palliative care. This study suggested further targeted education programmes, especially in special symptom management, interagency and multidisciplinary communication.


Assuntos
Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Enfermeiras e Enfermeiros , Humanos , Cuidados Paliativos , Estudos Transversais , Autorrelato , Inquéritos e Questionários , Competência Clínica
20.
Plant Dis ; 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35581908

RESUMO

'Thai Gold' yellow pitahaya (family Cactaceae, Selenicereus megalanthus) is a new crop being planted commercially in Malaysia. In May 2021, reddish-brown necrotic lesions were observed on the stems of approximately 60% of 'yellow pitahaya' plants in the field (~8 ha) located in the district Keningau of Sabah, Malaysia (5°20'53.1"N 116°06'23.0"E). As the disease progressed, the smaller lesions merged into larger irregularly shaped areas that formed dark brown in color. Stems with reddish-brown spot symptoms from ten plants were collected from the field and brought to the laboratory in sterilized paper bags. The symptom margin was excised into small blocks (5 x 5 x 5 mm). The blocks were surface sterilized based on Khoo et al. (2022), and placed on potato dextrose agar (PDA). The pathogens were isolated (three isolates were obtained) and cultured on potato dextrose agar (PDA) at 25°C for 5 days in the dark. The isolates developed floccose, white colony that darkened with age in PDA. Conidia (n = 30) were single celled, black, smooth, globose to subglobose, 13.9 to 18.7 µm in diameter, and borne singly on a hyaline vesicle at the tip of each conidiophore. Genomic DNA was extracted from fresh mycelia based on Khoo et al. (2021) and Khoo et al. (2022). Amplification of the internal transcribed spacer (ITS) region of rDNA, translation elongation factor 1-α (tef1-a) region and ß-tubulin (tub2) genes were performed using ITS1/ITS4 (White et al. 1990), EF1-728F/EF2 (O'Donnell et al. 1998; Carbone and Kohn, 1999) and T10/Bt2b (Glass and Donaldson, 1995; O'Donnell and Cigelnik, 1997) primer sets, respectively. The products were sent to Apical Scientific Sdn. Bhd. for purification and sequencing. BLASTn analysis of the newly generated ITS (OK448496, OM832586, OM832589) were 100% identical to Nigrospora sphaerica isolate 1SS (MN339998) (507/507 bp), tef1-a (OM223859, OM826971, OM826972) were 100% identical to Nigrospora sphaerica isolate F (MT708197) (497/497 bp) and tub2 (OL697400, OM826973, OM826974) were 100% identical to Nigrospora sphaerica isolate SN180517 (MN719407) (434/434 bp). The isolates established a supported clade to the related N. sphaerica type sequences, according to phylogenetic analysis using maximum likelihood based on the concatenated ITS, tef1-a and tub2 sequences. Morphological and molecular characterization matched the description of N. sphaerica (Kee et al. 2019). Koch's postulates were performed by spray inoculation (106 spores/ml) of isolate Keningau on the stem of three 'Thai Gold' yellow pitahaya plants in growth stage 4 (BBCH code: 419) (Kishore, 2016), while water was sprayed on three mock controls. The experiment was repeated using isolate Keningau02 and Keningau03 as inoculants. The inoculated stems on yellow pitahaya plants were covered with plastics for 48 h, and the plants were maintained in a greenhouse at room temperature 25 to 28°C with a relative humidity of 80 to 90%. All the inoculated stems developed symptoms 5 days post-inoculation, whereas no symptoms occurred on mock controls, thus fulfilling the Koch's postulates. No pathogen was isolated from the mock controls. The experiments were repeated two more times for each isolate. The reisolated fungi were identical to N. sphaerica morphologically and molecularly. Previously, N. sphaerica has been reported to cause stem brown spot disease on S. megalanthus in the Philippines (Taguiam et al. 2020). To our knowledge, this is the first report of N. sphaerica causing stem brown spot on 'Thai Gold' S. megalanthus in Malaysia. Our findings serve as a warning for the authorities and farmers that the disease threat has appeared for the Malaysian yellow pitahaya production.

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