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1.
Nat Immunol ; 22(1): 25-31, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33154590

RESUMO

Clinical manifestations of COVID-19 caused by the new coronavirus SARS-CoV-2 are associated with age1,2. Adults develop respiratory symptoms, which can progress to acute respiratory distress syndrome (ARDS) in the most severe form, while children are largely spared from respiratory illness but can develop a life-threatening multisystem inflammatory syndrome (MIS-C)3-5. Here, we show distinct antibody responses in children and adults after SARS-CoV-2 infection. Adult COVID-19 cohorts had anti-spike (S) IgG, IgM and IgA antibodies, as well as anti-nucleocapsid (N) IgG antibody, while children with and without MIS-C had reduced breadth of anti-SARS-CoV-2-specific antibodies, predominantly generating IgG antibodies specific for the S protein but not the N protein. Moreover, children with and without MIS-C had reduced neutralizing activity as compared to both adult COVID-19 cohorts, indicating a reduced protective serological response. These results suggest a distinct infection course and immune response in children independent of whether they develop MIS-C, with implications for developing age-targeted strategies for testing and protecting the population.


Assuntos
Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , COVID-19/imunologia , Proteínas do Nucleocapsídeo/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adolescente , Adulto , Idoso , COVID-19/virologia , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/fisiologia , Adulto Jovem
2.
Cell ; 153(5): 1134-48, 2013 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-23664764

RESUMO

Epigenetic mechanisms have been proposed to play crucial roles in mammalian development, but their precise functions are only partially understood. To investigate epigenetic regulation of embryonic development, we differentiated human embryonic stem cells into mesendoderm, neural progenitor cells, trophoblast-like cells, and mesenchymal stem cells and systematically characterized DNA methylation, chromatin modifications, and the transcriptome in each lineage. We found that promoters that are active in early developmental stages tend to be CG rich and mainly engage H3K27me3 upon silencing in nonexpressing lineages. By contrast, promoters for genes expressed preferentially at later stages are often CG poor and primarily employ DNA methylation upon repression. Interestingly, the early developmental regulatory genes are often located in large genomic domains that are generally devoid of DNA methylation in most lineages, which we termed DNA methylation valleys (DMVs). Our results suggest that distinct epigenetic mechanisms regulate early and late stages of ES cell differentiation.


Assuntos
Metilação de DNA , Células-Tronco Embrionárias/metabolismo , Epigenômica , Regulação da Expressão Gênica no Desenvolvimento , Animais , Diferenciação Celular , Cromatina/metabolismo , Ilhas de CpG , Células-Tronco Embrionárias/citologia , Histonas/metabolismo , Humanos , Metilação , Neoplasias/genética , Regiões Promotoras Genéticas , Peixe-Zebra/embriologia
3.
Nat Methods ; 20(2): 276-283, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646897

RESUMO

Cryo-electron tomography (cryo-ET) has become a powerful approach to study the high-resolution structure of cellular macromolecular machines in situ. However, the current correlative cryo-fluorescence and electron microscopy lacks sufficient accuracy and efficiency to precisely prepare cryo-lamellae of target locations for subsequent cryo-ET. Here we describe a precise cryogenic fabrication system, ELI-TriScope, which sets electron (E), light (L) and ion (I) beams at the same focal point to achieve accurate and efficient preparation of a target cryo-lamella. ELI-TriScope uses a commercial dual-beam scanning electron microscope modified to incorporate a cryo-holder-based transfer system and embed an optical imaging system just underneath the vitrified specimen. Cryo-focused ion beam milling can be accurately navigated by monitoring the real-time fluorescence signal of the target molecule. Using ELI-TriScope, we prepared a batch of cryo-lamellae of HeLa cells targeting the centrosome with a success rate of ~91% and discovered new in situ structural features of the human centrosome by cryo-ET.


Assuntos
Tomografia com Microscopia Eletrônica , Elétrons , Humanos , Tomografia com Microscopia Eletrônica/métodos , Microscopia Crioeletrônica/métodos , Células HeLa , Substâncias Macromoleculares
4.
Am J Pathol ; 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39222908

RESUMO

The vaginal epithelium plays pivotal roles in host defense against pathogen invasion, contributing to the maintenance of an acidic microenvironment within the vaginal lumen through the activity of acid-base transport proteins. However, the precise defense mechanisms of the vaginal epithelium after a bacterial infection remain incompletely understood. This study showed that bacterial lipopolysaccharide (LPS) potentiated net proton efflux by up-regulating the expression of Na+-H+ exchanger 1 (NHE1) without affecting other acid-base transport proteins in vaginal epithelial cells. Pharmacologic inhibition or genetic knockdown of Toll-like receptor-4 and the extracellular signal-regulated protein kinase signaling pathway effectively counteracted the up-regulation of NHE1 and the enhanced proton efflux triggered by LPS in vaginal epithelial cells. In vivo studies revealed that LPS administration led to luminal acidification through the up-regulation of NHE1 expression in the rat vagina. Moreover, inhibition of NHE exhibited an impaired defense against acute bacterial infection in the rat vagina. These findings collectively indicate the active involvement of vaginal epithelial cells in facilitating luminal acidification during acute bacterial infection, offering potential insights into the treatment of bacterial vaginosis.

5.
J Biol Chem ; 299(6): 104752, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37100288

RESUMO

Homologs of the protein Get3 have been identified in all domains yet remain to be fully characterized. In the eukaryotic cytoplasm, Get3 delivers tail-anchored (TA) integral membrane proteins, defined by a single transmembrane helix at their C terminus, to the endoplasmic reticulum. While most eukaryotes have a single Get3 gene, plants are notable for having multiple Get3 paralogs. Get3d is conserved across land plants and photosynthetic bacteria and includes a distinctive C-terminal α-crystallin domain. After tracing the evolutionary origin of Get3d, we solve the Arabidopsis thaliana Get3d crystal structure, identify its localization to the chloroplast, and provide evidence for a role in TA protein binding. The structure is identical to that of a cyanobacterial Get3 homolog, which is further refined here. Distinct features of Get3d include an incomplete active site, a "closed" conformation in the apo-state, and a hydrophobic chamber. Both homologs have ATPase activity and are capable of binding TA proteins, supporting a potential role in TA protein targeting. Get3d is first found with the development of photosynthesis and conserved across 1.2 billion years into the chloroplasts of higher plants across the evolution of photosynthesis suggesting a role in the homeostasis of photosynthetic machinery.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fotossíntese , Adenosina Trifosfatases/metabolismo , Embriófitas , Retículo Endoplasmático/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
6.
Antimicrob Agents Chemother ; : e0034424, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39194261

RESUMO

Limited treatment options and multidrug-resistant (MDR) Klebsiella pneumoniae present a significant therapeutic challenge, underscoring the need for novel approaches. Drug repurposing is a promising tool for augmenting the activity of many antibiotics. This study aimed to identify novel synergistic drug combinations against K. pneumoniae based on drug repurposing. We used the clinically isolated GN 172867 MDR strain of K. pneumoniae to determine the reversal resistance activity of zidovudine (AZT). The combined effects of AZT and various antibiotics, including nitrofurantoin (NIT) and omadacycline (OMC), were examined using the checkerboard method, growth curves, and crystal violet assays to assess biofilms. An in vitro combination activity testing was carried out in 12 isolates of K. pneumoniae. In vivo murine urinary tract and lung infection models were used to evaluate the therapeutic effects of AZT + NIT and AZT + OMC, respectively. The fractional inhibitory concentration index and growth curve demonstrated that AZT synergized with NIT or OMC against K. pneumoniae strains. In addition, AZT + NIT inhibited biofilm formation and cleared mature biofilms. In vivo, compared with untreated GN 172867-infected mice, AZT + NIT and AZT + OMC treatment decreased colony counts in multiple tissues (P < 0.05) and pathological scores in the bladder and kidneys (P < 0.05) and increased the survival rate by 60% (P < 0.05). This study evaluated the combination of AZT and antibiotics to treat drug-resistant K. pneumoniae infections and found novel drug combinations for the treatment of acute urinary tract infections. These findings suggest that AZT may exert significant anti-resistance activity.

7.
Small ; 20(8): e2305765, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37821399

RESUMO

Solid proton electrolytes play a crucial role in various electrochemical energy storage and conversion devices. However, the development of fast proton conducting solid proton electrolytes at ambient conditions remains a significant challenge. In this study, a novel acidified nitrogen self-doped porous carbon material is presented that demonstrates exceptional superprotonic conduction for applications in solid-state proton battery. The material, designated as MSA@ZIF-8-C, is synthesized through the acidification of nitrogen-doped porous carbon, specifically by integrating methanesulfonic acid (MSA) into zeolitic imidazolate framework-derived nitrogen self-doped porous carbons (ZIF-8-C). This study reveals that MSA@ZIF-8-C achieves a record-high proton conductivity beyond 10-2  S cm-1 at ambient condition, along with good long-term stability, positioning it as a cutting-edge alternative solid proton electrolyte to the default aqueous H2 SO4 electrolyte in proton batteries.

8.
Plant Biotechnol J ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943653

RESUMO

Grain chalkiness is an undesirable trait that negatively regulates grain yield and quality in rice. However, the regulatory mechanism underlying chalkiness is complex and remains unclear. We identified a positive regulator of white-belly rate (WBR). The WBR7 gene encodes sucrose synthase 3 (SUS3). A weak functional allele of WBR7 is beneficial in increasing grain yield and quality. During the domestication of indica rice, a functional G/A variation in the coding region of WBR7 resulted in an E541K amino acid substitution in the GT-4 glycosyltransferase domain, leading to a significant decrease in decomposition activity of WBR7A (allele in cultivar Jin23B) compared with WBR7G (allele in cultivar Beilu130). The NIL(J23B) and knockout line NIL(BL130)KO exhibited lower WBR7 decomposition activity than that of NIL(BL130) and NIL(J23B)COM, resulting in less sucrose decomposition and metabolism in the conducting organs. This caused more sucrose transportation to the endosperm, enhancing the synthesis of storage components in the endosperm and leading to decreased WBR. More sucrose was also transported to the anthers, providing sufficient substrate and energy supply for pollen maturation and germination, ultimately leading to an increase rate of seed setting and increased grain yield. Our findings elucidate a mechanism for enhancing rice yield and quality by modulating sucrose metabolism and allocation, and provides a valuable allele for improved rice quality.

9.
Plant Biotechnol J ; 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39180364

RESUMO

Starch is synthesized as insoluble, semicrystalline particles within plant chloroplast and amyloplast, which are referred to as starch grains (SGs). The size and morphology of SGs in the cereal endosperm are diverse and species-specific, representing a key determinant of the suitability of starch for industrial applications. However, the molecular mechanisms modulating SG size in cereal endosperm remain elusive. Here, we functionally characterized the rice (Oryza sativa) mutant substandard starch grain7 (ssg7), which exhibits enlarged SGs and defective endosperm development. SSG7 encodes a plant-specific DUF1001 domain-containing protein homologous to Arabidopsis (Arabidopsis thaliana) CRUMPLED LEAF (AtCRL). SSG7 localizes to the amyloplast membrane in developing endosperm. Several lines of evidence suggest that SSG7 functions together with SSG4 and SSG6, known as two regulators essential for SG development, to control SG size, by interacting with translocon-associated components, which unveils a molecular link between SG development and protein import. Genetically, SSG7 acts synergistically with SSG4 and appears to be functional redundancy with SSG6 in modulating SG size and endosperm development. Collectively, our findings uncover a multimeric functional protein complex involved in SG development in rice. SSG7 represents a promising target gene for the biotechnological modification of SG size, particularly for breeding programs aimed at improving starch quality.

10.
J Antimicrob Chemother ; 79(9): 2246-2250, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39011845

RESUMO

OBJECTIVES: To establish the epidemiology cut-off (ECOFF) values of eravacycline against Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, Acinetobacter baumannii and Staphylococcus aureus, from a multi-centre study in China. METHODS: We collected 2500 clinical isolates from five hospitals in China from 2017 to 2020. The MICs of eravacycline were determined using broth microdilution. The ECOFF values of eravacycline against the five species commonly causing cIAIs were calculated using visual estimation and ECOFFinder following the EUCAST guideline. RESULTS: The MICs of eravacycline against all the strains were in the range of 0.004-16 mg/L. The ECOFF values of eravacycline were 0.5 mg/L for E. coli, 2 mg/L for K. pneumonia and E. cloacae, and 0.25 mg/L for A. baumannii and S. aureus, consistent with the newest EUCAST publication of eravacycline ECOFF values for the populations. No discrepancy was found between the visually estimated and 99.00% ECOFF values calculated using ECOFFinder. CONCLUSIONS: The determined ECOFF values of eravacycline against the five species can assist in distinguishing wild-type from non-wild-type strains. Given its promising activity, eravacycline may represent a member of the tetracycline class in treating cIAIs caused by commonly encountered Gram-negative and Gram-positive pathogens.


Assuntos
Acinetobacter baumannii , Antibacterianos , Enterobacter cloacae , Escherichia coli , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Tetraciclinas , Humanos , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Tetraciclinas/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/isolamento & purificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , China/epidemiologia
11.
Opt Express ; 32(4): 4887-4901, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439229

RESUMO

In underwater wireless optical communication, orbital angular momentum (OAM) states suffer from turbulence distortions. This study aims to investigate the effectiveness of auto-focusing and OAM entanglement of the beams in reducing the turbulence effects. We implement the single-phase approximation and the extended Huygens-Fresnel principle to derive the detection probability of the entangled Airy beams under unstable oceanic turbulence. The results show that auto-focusing can protect the signal OAM mode and suppress modal crosstalks, while entangled OAM states can further enhance the resistance against oceanic turbulence around the focus position. The numerical analysis demonstrates that after the auto-focusing position, the beams evolve in completely opposite directions, indicating that the focal length should be modulated according to the length of a practical link to enhance received signals. These findings suggest that entangled auto-focusing vortex beams may be a desirable light source in underwater communication systems.

12.
BMC Cancer ; 24(1): 246, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388861

RESUMO

BACKGROUND: Artificial intelligence (AI)-assisted clinical trial screening is a promising prospect, although previous matching systems were developed in English, and relevant studies have only been conducted in Western countries. Therefore, we evaluated an AI-based clinical trial matching system (CTMS) that extracts medical data from the electronic health record system and matches them to clinical trials automatically. METHODS: This study included 1,053 consecutive inpatients primarily diagnosed with hepatocellular carcinoma who were referred to the liver tumor center of an academic medical center in China between January and December 2019. The eligibility criteria extracted from two clinical trials, patient attributes, and gold standard were decided manually. We evaluated the performance of the CTMS against the established gold standard by measuring the accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and run time required. RESULTS: The manual reviewers demonstrated acceptable interrater reliability (Cohen's kappa 0.65-0.88). The performance results for the CTMS were as follows: accuracy, 92.9-98.0%; sensitivity, 51.9-83.5%; specificity, 99.0-99.1%; PPV, 75.7-85.1%; and NPV, 97.4-98.9%. The time required for eligibility determination by the CTMS and manual reviewers was 2 and 150 h, respectively. CONCLUSIONS: We found that the CTMS is particularly reliable in excluding ineligible patients in a significantly reduced amount of time. The CTMS excluded ineligible patients for clinical trials with good performance, reducing 98.7% of the work time. Thus, such AI-based systems with natural language processing and machine learning have potential utility in Chinese clinical trials.


Assuntos
Inteligência Artificial , Carcinoma Hepatocelular , Neoplasias Hepáticas , Seleção de Pacientes , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , China/epidemiologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Ensaios Clínicos como Assunto , Hospitalização
13.
Liver Int ; 44(6): 1435-1447, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38483145

RESUMO

BACKGROUND AND AIMS: The use of corticosteroids in chronic drug-induced liver injury (DILI) is an important issue. Our previous randomized controlled trial showed that patients with chronic DILI benefited from a 48-week steroid stepwise reduction (SSR) regimen. However, it remains unclear whether a shorter course of therapy can achieve similar efficacy. In this study, we aimed to assess whether a 36-week SSR can achieve efficacy similar to that of 48-week SSR. METHODS: A randomized open-label trial was performed. Eligible patients were randomly assigned to the 36- or 48-week (1:1) SSR group. Liver biopsies were performed at baseline and at the end of treatment. The primary outcome was the proportion of patients with relapse rate (RR). The secondary outcomes were improvement in liver histology and safety. RESULTS: Of the 90 participants enrolled, 84 (87.5%) completed the trial, and 62 patients (68.9%) were women. Hepatocellular damage was observed in 53.4% of the cohort. The RR was 7.1% in the 36-week SSR group but 4.8% in the 48-week SSR group, as determined by per-protocol set analysis (p = 1.000). Significant histological improvements in histological activity (93.1% vs. 92.9%, p = 1.000) and fibrosis (41.4% vs. 46.4%, p = .701) were observed in both the groups. Biochemical normalization time did not differ between the two groups. No severe adverse events were observed. CONCLUSIONS: Both the 36- and 48-week SSR regimens demonstrated similar biochemical response and histological improvements with good safety, supporting 36-week SSR as a preferable therapeutic choice (ClinicalTrials.gov, NCT03266146).


Assuntos
Fígado , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto , Fígado/patologia , Fígado/efeitos dos fármacos , Doença Hepática Crônica Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Crônica Induzida por Substâncias e Drogas/etiologia , Resultado do Tratamento , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Recidiva , Idoso , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Esquema de Medicação
14.
Pediatr Res ; 95(4): 959-965, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38012310

RESUMO

BACKGROUND: Tie2, a functional angiopoietin receptor, is expressed in vascular endothelial cells and plays an important role in angiogenesis and vascular stability. This study aimed to evaluate the effects of an agonistic Tie2 signal on renal interstitial fibrosis (RIF) and elucidate the underlying mechanisms. METHODS: We established an in vivo mouse model of folic acid-induced nephropathy (FAN) and an in vitro model of lipopolysaccharide-stimulated endothelial cell injury, then an agonistic Tie2 monoclonal antibody (Tie2 mAb) was used to intervent these processes. The degree of tubulointerstitial lesions and related molecular mechanisms were determined by histological assessment, immunohistochemistry, western blotting, and qPCR. RESULTS: Tie2 mAb attenuated RIF and reduced the level of fibroblast-specific protein 1 (FSP1). Further, it suppressed vascular cell adhesion molecule-1 (VCAM-1) and increased CD31 density in FAN. In the in vitro model, Tie2 mAb was found to decrease the expression of VCAM-1, Bax, and α-smooth muscle actin (α-SMA). CONCLUSIONS: The present findings indicate that the agonistic Tie2 mAb exerted vascular protective effects and ameliorated RIF via inhibition of vascular inflammation, apoptosis, and fibrosis. Therefore, Tie2 may be a potential target for the treatment of this disease. IMPACT: This is the first report to confirm that an agonistic Tie2 monoclonal antibody can reduce renal interstitial fibrosis in folic acid-induced nephropathy in mice. This mechanism possibly involves vascular protective effects brought about by inhibition of vascular inflammation, apoptosis and fibrosis. Our data show that Tie2 signal may be a novel, endothelium-specific target for the treatment of tubulointerstitial fibrosis.


Assuntos
Células Endoteliais , Nefropatias , Camundongos , Animais , Células Endoteliais/metabolismo , Receptor TIE-2/metabolismo , Molécula 1 de Adesão de Célula Vascular , Fibrose , Anticorpos Monoclonais/farmacologia , Nefropatias/induzido quimicamente , Ácido Fólico , Inflamação , Angiopoietina-1 , Angiopoietina-2
15.
BMC Infect Dis ; 24(1): 936, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39251906

RESUMO

BACKGROUND: Human adenovirus (HAdV) is an important pathogen causing acute respiratory infection (ARI) in children. Many countries, including China, have experienced sporadic or outbreaks related to HAdV-4, and death cases were reported. However, there is little research on HAdV-4 and the epidemic situation of HAdV-4 in China is little known. This study was designed to comprehend the prevalence and genetic characteristics of HAdV-4 in ARI children in China. METHODS: Respiratory tract samples from ARI children hospitalized in six hospitals of Northern and Southern China from 2017 to 2020 were collected for HAdV detection and typing. Clinical information was collected from HAdV-4 positive patients for clinical characteristics and epidemiological analysis. The main capsid proteins and the whole genome sequences were amplified and sequenced for bioinformatics analysis. RESULTS: There were 2847 ARI children enrolled, and 156 (5.48%) HAdV positive samples were detected. Eleven HAdV-4 positive samples were identified, accounting for 0.39% of the total samples and 7.05% of the HAdV positive samples. The main manifestations were fever and cough. Two children had conjunctivitis. Two children were diagnosed with severe pneumonia and developed respiratory failure. One of them developed hemophagocytic syndrome and checked in pediatric intensive care unit (PICU). This child had ventricular septal defect. All the children recovered. The isolated strains of HAdV-4 obtained in this study and the reference strains from China located in the same phylogenetic branch (HAdV-4a), while the prototype strain and vaccine strains formed another branch (HAdV-4p). Upon comparison with the prototype strain, there were a few amino acid mutations existing in three major capsid proteins. According to recombination analysis, no new recombination was found. CONCLUSIONS: The detection rate of HAdV-4 in children hospitalized with ARI was 0.39% in the total samples and 7.05% of all HAdV positive samples. HAdV-4 isolates obtained in this study and other reference strains from China belonged to the HAdV-4a subtype. Our data provided reference for the monitoring, prevention and control of HAdV-4, as well as the research and development of vaccines and drugs.


Assuntos
Infecções por Adenovirus Humanos , Adenovírus Humanos , Filogenia , Infecções Respiratórias , Humanos , China/epidemiologia , Adenovírus Humanos/genética , Adenovírus Humanos/isolamento & purificação , Adenovírus Humanos/classificação , Infecções Respiratórias/virologia , Infecções Respiratórias/epidemiologia , Infecções por Adenovirus Humanos/epidemiologia , Infecções por Adenovirus Humanos/virologia , Masculino , Pré-Escolar , Feminino , Estudos Prospectivos , Lactente , Criança , Proteínas do Capsídeo/genética , Prevalência
16.
J Gastroenterol Hepatol ; 39(6): 1134-1144, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615196

RESUMO

BACKGROUND AND AIM: Small heterodimer partner (SHP, encoded by NR0B2) plays an important role in maintaining bile acid homeostasis. The loss of the hepatic farnesoid X receptor (FXR)/SHP signal can cause severe cholestatic liver injury (CLI). FXR and SHP have overlapping and nonoverlapping functions in bile acid homeostasis. However, the key role played by SHP in CLI is unclear. METHODS: In this study, an alpha-naphthylisothiocyanate (ANIT)-induced cholestasis mouse model was established. The effect of SHP knockout (SHP-KO) on liver and ileal pathology was evaluated. 16S rRNA gene sequencing analysis combined with untargeted metabolomics was applied to reveal the involvement of SHP in the pathogenesis of CLI. RESULTS: The results showed that ANIT (75 mg/kg) induced cholestasis in WT mice. No significant morphological changes were found in the liver and ileal tissue of SHP-KO mice. However, the serum metabolism and intestinal flora characteristics were significantly changed. Moreover, compared with the WT + ANIT group, the serum levels of ALT and AST in the SHP-KO + ANIT group were significantly increased, and punctate necrosis in the liver tissue was more obvious. The ileum villi showed obvious shedding, thinning, and shortening. In addition, SHP-KO-associated differential intestinal flora and differential biomarkers were significantly associated. CONCLUSION: In this study, we elucidated the serum metabolic characteristics and intestinal flora changes related to the aggravation of CLI in SHP-KO mice induced by ANIT.


Assuntos
1-Naftilisotiocianato , Colestase , Modelos Animais de Doenças , Progressão da Doença , Fígado , Camundongos Knockout , Receptores Citoplasmáticos e Nucleares , Animais , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Colestase/metabolismo , Colestase/patologia , Fígado/patologia , Fígado/metabolismo , 1-Naftilisotiocianato/toxicidade , Masculino , Íleo/patologia , Íleo/metabolismo , Microbioma Gastrointestinal , Camundongos , Ácidos e Sais Biliares/metabolismo , Camundongos Endogâmicos C57BL
17.
J Opt Soc Am A Opt Image Sci Vis ; 41(6): B106-B115, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856418

RESUMO

The evolution of the information transfer capability of an optical system for underwater focused wave mode localized wave (FWMLW) in anisotropic weakly turbulent absorbing seawater is studied. By developing the probability distribution function as well as the detection probability of the vortex modes carried by the FWMLW and the average bit error rate of the FWMLW underwater system, the information capacity of the FWMLW system with a pointing error is modeled. Through a numerical analysis of the effects of turbulent seawater and optical system parameters on the built light intensity, the detection probability, and the information capacity models, we find that the FWMLW system has an optimal delay time determined by the spectrum bandwidth when the spectrum bandwidth is greater than 1. The information capacity of the FWMLW system is higher than that of the X localized wave system under the same turbulent seawater channel condition, and FWMLW is a better optical signal source for vortex mode division multiplexing underwater systems than a Bessel-Gaussian beam.

18.
J Opt Soc Am A Opt Image Sci Vis ; 41(5): 943-951, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38856580

RESUMO

Compared to horizontal transmission, the oceanic dissipation rate and temperature-salinity distribution ratio are no longer constant but vary with depth, imposing greater complexity on oceanic turbulence when beams propagate through a slant path and resulting in more limitations on the performance of underwater wireless optical communication (UWOC) links. This study focuses on investigating the performance, especially the auto-focusing characteristic, of auto-focusing hypergeometric Gaussian (AHGG) beams propagating along slant paths in oceanic turbulence. We theoretically derive the spatial coherence radius and the relative probability of the orbital angular momentum (OAM) mode for AHGG beams passing through such links. Numerical simulations reveal that AHGG beams exhibit superior propagation performance compared to hypergeometric Gaussian beams. Lower beam orders and OAM numbers contribute to improved performance, while careful selection of auto-focusing length can tangibly enhance detection performance as well. Additionally, tidal velocities and wind speeds have nonnegligible effects on OAM signal probability. Our results further demonstrate that surface buoyancy flux, temperature gradients, and waterside friction velocity significantly affect beam transmission under varying wind conditions. These findings, particularly controlling the auto-focusing length of AHGG beams to match the transmission distance, provide valuable insights for enhancing the quality of UWOC links.

19.
Mol Cell ; 62(2): 284-294, 2016 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-27105118

RESUMO

Natural variations in gene expression provide a mechanism for multiple phenotypes to arise in an isogenic bacterial population. In particular, a sub-group termed persisters show high tolerance to antibiotics. Previously, their formation has been attributed to cell dormancy. Here we demonstrate that bacterial persisters, under ß-lactam antibiotic treatment, show less cytoplasmic drug accumulation as a result of enhanced efflux activity. Consistently, a number of multi-drug efflux genes, particularly the central component TolC, show higher expression in persisters. Time-lapse imaging and mutagenesis studies further establish a positive correlation between tolC expression and bacterial persistence. The key role of efflux systems, among multiple biological pathways involved in persister formation, indicates that persisters implement a positive defense against antibiotics prior to a passive defense via dormancy. Finally, efflux inhibitors and antibiotics together effectively attenuate persister formation, suggesting a combination strategy to target drug tolerance.


Assuntos
Antibacterianos/farmacologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Compostos de Boro/farmacologia , Farmacorresistência Bacteriana , Proteínas de Escherichia coli/metabolismo , Escherichia coli/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo , Penicilinas/farmacologia , Antibacterianos/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Transporte Biológico , Compostos de Boro/metabolismo , Contagem de Colônia Microbiana , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Membrana Transportadoras/genética , Viabilidade Microbiana/efeitos dos fármacos , Mutação , Imagem Óptica , Penicilinas/metabolismo , Fenótipo , Fatores de Tempo , Regulação para Cima
20.
Mol Cell ; 61(3): 461-473, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26833089

RESUMO

Detailed genomic contact maps have revealed that chromosomes are structurally organized in megabase-sized topologically associated domains (TADs) that encompass smaller subTADs. These domains segregate in the nuclear space to form active and inactive nuclear compartments, but cause and consequence of compartmentalization are largely unknown. Here, we combined lacO/lacR binding platforms with allele-specific 4C technologies to track their precise position in the three-dimensional genome upon recruitment of NANOG, SUV39H1, or EZH2. We observed locked genomic loci resistant to spatial repositioning and unlocked loci that could be repositioned to different nuclear subcompartments with distinct chromatin signatures. Focal protein recruitment caused the entire subTAD, but not surrounding regions, to engage in new genomic contacts. Compartment switching was found uncoupled from transcription changes, and the enzymatic modification of histones per se was insufficient for repositioning. Collectively, this suggests that trans-associated factors influence three-dimensional compartmentalization independent of their cis effect on local chromatin composition and activity.


Assuntos
Núcleo Celular/metabolismo , Segregação de Cromossomos , Células-Tronco Embrionárias/metabolismo , Loci Gênicos , Óperon Lac , Repressores Lac/metabolismo , Animais , Células Cultivadas , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina , Proteína Potenciadora do Homólogo 2 de Zeste , Regulação da Expressão Gênica , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Repressores Lac/genética , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Proteína Homeobox Nanog , Complexo Repressor Polycomb 2/genética , Complexo Repressor Polycomb 2/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transfecção
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