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1.
N Engl J Med ; 387(15): 1373-1384, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36239645

RESUMO

BACKGROUND: The effects and risks of endovascular thrombectomy 6 to 24 hours after stroke onset due to basilar-artery occlusion have not been extensively studied. METHODS: In a trial conducted over a 5-year period in China, we randomly assigned, in a 1:1 ratio, patients with basilar-artery stroke who presented between 6 to 24 hours after symptom onset to receive either medical therapy plus thrombectomy or medical therapy only (control). The original primary outcome, a score of 0 to 4 on the modified Rankin scale (range, 0 to 6, with a score of 0 indicating no disability, 4 moderately severe disability, and 6 death) at 90 days, was changed to a good functional status (a modified Rankin scale score of 0 to 3, with a score of 3 indicating moderate disability). Primary safety outcomes were symptomatic intracranial hemorrhage at 24 hours and 90-day mortality. RESULTS: A total of 217 patients (110 in the thrombectomy group and 107 in the control group) were included in the analysis; randomization occurred at a median of 663 minutes after symptom onset. Enrollment was halted at a prespecified interim analysis because of the superiority of thrombectomy. Thrombolysis was used in 14% of the patients in the thrombectomy group and in 21% of those in the control group. A modified Rankin scale score of 0 to 3 (primary outcome) occurred in 51 patients (46%) in the thrombectomy group and in 26 (24%) in the control group (adjusted rate ratio, 1.81; 95% confidence interval [CI], 1.26 to 2.60; P<0.001). The results for the original primary outcome of a modified Rankin scale score of 0 to 4 were 55% and 43%, respectively (adjusted rate ratio, 1.21; 95% CI, 0.95 to 1.54). Symptomatic intracranial hemorrhage occurred in 6 of 102 patients (6%) in the thrombectomy group and in 1 of 88 (1%) in the control group (risk ratio, 5.18; 95% CI, 0.64 to 42.18). Mortality at 90 days was 31% in the thrombectomy group and 42% in the control group (adjusted risk ratio, 0.75; 95% CI, 0.54 to 1.04). Procedural complications occurred in 11% of the patients who underwent thrombectomy. CONCLUSIONS: Among patients with stroke due to basilar-artery occlusion who presented 6 to 24 hours after symptom onset, thrombectomy led to a higher percentage with good functional status at 90 days than medical therapy but was associated with procedural complications and more cerebral hemorrhages. (Funded by the Chinese National Ministry of Science and Technology; BAOCHE ClinicalTrials.gov number, NCT02737189.).


Assuntos
Arteriopatias Oclusivas , Artéria Basilar , Procedimentos Endovasculares , Acidente Vascular Cerebral , Trombectomia , Humanos , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/tratamento farmacológico , Arteriopatias Oclusivas/mortalidade , Arteriopatias Oclusivas/cirurgia , Artéria Basilar/efeitos dos fármacos , Artéria Basilar/cirurgia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Isquemia Encefálica/mortalidade , Isquemia Encefálica/cirurgia , Avaliação da Deficiência , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/etiologia , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Trombectomia/métodos , Fatores de Tempo , Resultado do Tratamento
2.
Anal Chem ; 96(26): 10705-10713, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38910291

RESUMO

Circulating tumor cells (CTCs) serve as important biomarkers in the liquid biopsy of hepatocellular carcinoma (HCC). Herein, a homogeneous dual fluorescence indicators aptasensing strategy is described for CTCs in HCC, with the core assistance of a steric hindrance-mediated enzymatic reaction. CTCs in the sample could specifically bind to a 5'-biotin-modified glypican-3 (GPC3) aptamer and remove the steric hindrance formed by the biotin-streptavidin system. This influences the efficiency of the terminal deoxynucleotidyl transferase enzymatic reaction. Then, methylene blue (MB) was introduced to react with the main product poly cytosine (polyC) chain, and trivalent cerium ion (Ce3+) was added to react with the byproduct pyrophosphate to form fluorescent pyrophosphate cerium coordination polymeric nanoparticles. Finally, the CTCs were quantified by dual fluorescence indicators analysis. Under optimized conditions, the linear range was 5 to 104 cells/mL, and the limits of detection reached 2 cells/mL. Then, 40 clinical samples (15 healthy and 25 HCC patients) were analyzed. The receiver operating characteristic curve analysis revealed an area under the curve of 0.96, a sensitivity of 92%, and a specificity of 100%. Therefore, this study established a sensitive and accurate CTCs sensing system for clinical HCC patients, promoting early tumor diagnosis.


Assuntos
Aptâmeros de Nucleotídeos , Carcinoma Hepatocelular , Corantes Fluorescentes , Neoplasias Hepáticas , Células Neoplásicas Circulantes , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , Células Neoplásicas Circulantes/patologia , Células Neoplásicas Circulantes/metabolismo , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Glipicanas/metabolismo , Técnicas Biossensoriais
3.
J Neurosci Res ; 102(3): e25324, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38515341

RESUMO

Patients with symptomatic intracranial arterial stenosis (sICAS) suffer embarrassed hemodynamic status and acute ischemic stroke (AIS) recurrence. We aimed to assess the efficacy of remote ischemic conditioning (RIC) on improving this status by evaluating cerebral blood flow (CBF) and cerebral glucose metabolism (CGM) via PET/CT. Adult patients with unilateral sICAS in middle cerebral artery and/or intracranial segment of internal carotid artery-related AIS or transient ischemic attack within 6 months prior to randomization were enrolled. Individuals who received intravenous thrombolysis or endovascular treatment, or sICAS caused by cardiac embolism, small vessel occlusion, or other determined causes were excluded. Twenty-three eligible patients were randomly assigned to standard medical treatment (SMT) (n = 10) or RIC group (n = 13). The RIC protocol consisted of 5 cycles, each for 5-min bilateral upper limb ischemia and 5-min reperfusion period, twice a day, with a total duration of 3 months. Ten healthy volunteers were enrolled as healthy control group. We tested CBF and CGM at the rest stage and the methazolamide-induced stress stage. All patients received PET/CT at baseline and three-month followup. Both CBF and CGM in ipsilateral hemisphere of sICAS patients were significantly decreased at the rest stage and the stress stage (p < .05), which were improved by three-month RIC (p < .05). The lesions decreased notably in RIC group compared to SMT group (p < .05). RIC ameliorated the hemodynamic status and glucose metabolism in regions at high risk of infarction, which might improve the resistance capacity towards ischemic load in sICAS patients.


Assuntos
Arteriosclerose Intracraniana , AVC Isquêmico , Adulto , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Arteriosclerose Intracraniana/diagnóstico por imagem , Arteriosclerose Intracraniana/terapia , Isquemia , Hemodinâmica , Glucose
4.
Theor Appl Genet ; 137(6): 121, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709317

RESUMO

KEY MESSAGE: This study precisely mapped and validated a quantitative trait locus (QTL) located on chromosome 4B for flag leaf angle in wheat. Flag leaf angle (FLANG) is closely related to crop architecture and yield. We previously identified the quantitative trait locus (QTL) QFLANG-4B for FLANG on chromosome 4B, located within a 14-cM interval flanked by the markers Xbarc20 and Xzyh357, using a mapping population of recombinant inbred lines (RILs) derived from a cross between Nongda3331 (ND3331) and Zang1817. In this study, we fine-mapped QFLANG-4B and validated its associated genetic effect. We developed a BC3F3 population using ND3331 as the recurrent parent through marker-assisted selection, as well as near-isogenic lines (NILs) by selfing BC3F3 plants carrying different heterozygous segments for the QFLANG-4B region. We obtained eight recombinant types for QFLANG-4B, narrowing its location down to a 5.3-Mb region. This region contained 76 predicted genes, 7 of which we considered to be likely candidate genes for QFLANG-4B. Marker and phenotypic analyses of individual plants from the secondary mapping populations and their progeny revealed that the FLANG of the ND3331 allele is significantly higher than that of the Zang1817 allele in multiple environments. These results not only provide a basis for the map-based cloning of QFLANG-4B, but also indicate that QFLANG-4B has great potential for marker-assisted selection in wheat breeding programs designed to improve plant architecture and yield.


Assuntos
Mapeamento Cromossômico , Folhas de Planta , Locos de Características Quantitativas , Triticum , Mapeamento Cromossômico/métodos , Cromossomos de Plantas/genética , Genes de Plantas , Ligação Genética , Marcadores Genéticos , Fenótipo , Melhoramento Vegetal , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Triticum/genética , Triticum/crescimento & desenvolvimento , Triticum/anatomia & histologia
5.
BMC Geriatr ; 24(1): 222, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38439017

RESUMO

BACKGROUND: This study aimed to investigate the association of high-sensitivity C-reactive protein (hs-CRP) with incident frailty as well as its effects on pre-frailty progression and regression among middle-aged and older adults. METHODS: Based on the frailty index (FI) calculated with 41 items, 6890 eligible participants without frailty at baseline from China Health and Retirement Longitudinal Study (CHARLS) were categorized into health, pre-frailty, and frailty groups. Logistic regression models were used to estimate the longitudinal association between baseline hs-CRP and incident frailty. Furthermore, a series of genetic approaches were conducted to confirm the causal relationship between CRP and frailty, including Linkage disequilibrium score regression (LDSC), pleiotropic analysis, and Mendelian randomization (MR). Finally, we evaluated the association of hs-CRP with pre-frailty progression and regression. RESULTS: The risk of developing frailty was 1.18 times (95% CI: 1.03-1.34) higher in participants with high levels of hs-CRP at baseline than low levels of hs-CRP participants during the 3-year follow-up. MR analysis suggested that genetically determined hs-CRP was potentially positively associated with the risk of frailty (OR: 1.06, 95% CI: 1.03-1.08). Among 5241 participants with pre-frailty at baseline, we found pre-frailty participants with high levels of hs-CRP exhibit increased odds of progression to frailty (OR: 1.39, 95% CI: 1.09-1.79) and decreased odds of regression to health (OR: 0.84, 95% CI: 0.72-0.98) when compared with participants with low levels of hs-CRP. CONCLUSIONS: Our results suggest that reducing systemic inflammation is significant for developing strategies for frailty prevention and pre-frailty reversion in the middle-aged and elderly population.


Assuntos
Proteína C-Reativa , Fragilidade , Idoso , Humanos , Pessoa de Meia-Idade , Estudos Longitudinais , Proteína C-Reativa/genética , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Fragilidade/genética , Estudos de Coortes , Inflamação
6.
Proc Natl Acad Sci U S A ; 118(7)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33526596

RESUMO

The RNA polymerase inhibitor favipiravir is currently in clinical trials as a treatment for infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), despite limited information about the molecular basis for its activity. Here we report the structure of favipiravir ribonucleoside triphosphate (favipiravir-RTP) in complex with the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) bound to a template:primer RNA duplex, determined by electron cryomicroscopy (cryoEM) to a resolution of 2.5 Å. The structure shows clear evidence for the inhibitor at the catalytic site of the enzyme, and resolves the conformation of key side chains and ions surrounding the binding pocket. Polymerase activity assays indicate that the inhibitor is weakly incorporated into the RNA primer strand, and suppresses RNA replication in the presence of natural nucleotides. The structure reveals an unusual, nonproductive binding mode of favipiravir-RTP at the catalytic site of SARS-CoV-2 RdRp, which explains its low rate of incorporation into the RNA primer strand. Together, these findings inform current and future efforts to develop polymerase inhibitors for SARS coronaviruses.


Assuntos
Amidas/farmacologia , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismo , Inibidores Enzimáticos/farmacologia , Pirazinas/farmacologia , SARS-CoV-2/ultraestrutura , Amidas/química , RNA-Polimerase RNA-Dependente de Coronavírus/antagonistas & inibidores , RNA-Polimerase RNA-Dependente de Coronavírus/química , Microscopia Crioeletrônica/métodos , Inibidores Enzimáticos/química , Pirazinas/química , Ribonucleotídeos/química , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Imagem Individual de Molécula/métodos
7.
Endocr Res ; 49(2): 92-105, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38288985

RESUMO

Purpose:Osteoporosis is characterized by low bone mineral density (BMD) and high risk of osteoporotic fracture (OF). Peripheral blood monocytes (PBM) can differentiate into osteoclasts to resorb bone. This study was to identify PBM-expressed proteins significant for osteoporosis in Chinese Han elderly population (>65 years), and focused on two phenotypes of osteoporosis: low BMD and OF. METHODS: Label-free quantitative proteomics was employed to profile PBM proteome and to identify differentially expressed proteins (DEPs) between OF (N=27) vs. non-fractured (NF, N=24) subjects and between low BMD (N=12) vs. high BMD (N=12) subjects in women. Western blotting (WB) was conducted to validate differential expression, and ELISA to evaluate translational value for secretory protein of interest. RESULTS: We discovered 59 DEPs with fold change (FC)>1.3 (P<1×10-5), and validated the significant up-regulation of pyruvate kinase isozyme 2 (PKM2) with osteoporosis (P<0.001). PKM2 protein upregulation with OF was replicated with PBM in men (P=0.04). Plasma PKM2 protein level was significantly elevated with OF in an independent sample (N=100, FC=1.68, P=0.01). Pursuant functional assays showed that extracellular PKM2 protein supplement not only promoted monocyte trans-endothelial migration, growth, and osteoclast differentiation (marker gene expression), but also inhibited osteoblast growth, differentiation (ALP gene expression), and activity. CONCLUSION: The above findings suggest that PKM2 protein is a novel osteoporosis-associated functional protein in Chinese Han elderly population. It may serve as a risk biomarker and drug target for osteoporosis.


Assuntos
Densidade Óssea , Osteoporose , Piruvato Quinase , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Proteínas de Transporte/metabolismo , China , População do Leste Asiático , Monócitos/metabolismo , Fraturas por Osteoporose , Piruvato Quinase/metabolismo
8.
Stroke ; 54(9): 2442-2445, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37497674

RESUMO

BACKGROUND: Experimental studies have demonstrated the neuroprotection of ischemic postconditioning (IPostC) in acute ischemic stroke by attenuating ischemia-reperfusion injury. This study aimed to investigate the safety and tolerability of direct IPostC in both a dog model and patients with acute ischemic stroke treated with thrombectomy. METHODS: The study involved 2 parts. First, IPostC was induced by repeated balloon inflation and deflation in dogs, where a low-pressure balloon was navigated to the anterior spinal artery, and 4 cycles of 5-minute ischemia followed by 5-minute reperfusion were performed. Vascular injuries were assessed using angiography and vascular tissue specimens. Then, a 3+3 dose-escalation trial was conducted in patients with acute ischemic stroke following successful thrombectomy recanalization. Patients received direct IPostC with ischemia and reperfusion durations in progressive increments of 0, 1, 2, 3, 4, and 5 minutes ×4 cycles. Major adverse responses were defined as vessel perforation, rupture, dissection, reocclusion, severe vasospasm, thrombotic events, and rupture of the balloon. RESULTS: IPostC was investigated in 4 dogs. No vessel perforation or rupture, dissection, or vasospasm was observed under the angiography. Only 1 vessel experienced mild injury between the intima and the internal elastic membrane detected on a histopathologic slide. Then, 18 patients were recruited. The duration of IPostC was progressively escalated with no major response happened. No patient experienced agitation, discomfort, or other tolerability issues. Five patients (27.8%) experienced any intracranial hemorrhage after thrombectomy, and 1 (5.6%) was symptomatic. At 3-month follow-up, no patient died, and 9 patients (50%) achieved functional independence. CONCLUSIONS: Direct IPostC inducing by 4 cycles of 5-minute ischemia followed by 5-minute reperfusion is safe, feasible, and tolerable in patients with acute ischemic stroke treated with thrombectomy. Further investigations are needed to determine the safety and preliminary efficacy of direct IPostC. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT05153655.


Assuntos
Isquemia Encefálica , Pós-Condicionamento Isquêmico , AVC Isquêmico , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Animais , Cães , Traumatismo por Reperfusão/prevenção & controle , Hemorragias Intracranianas , Trombectomia/efeitos adversos , Acidente Vascular Cerebral/cirurgia , Isquemia Encefálica/cirurgia , Resultado do Tratamento
9.
BMC Genomics ; 24(1): 499, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37644462

RESUMO

This paper aims to explore the role of circRNA expression profiles and circRNA-associated ceRNA networks in the regulation of myogenesis in the longissimus dorsi of cattle breeds surviving under subtropical conditions in southern China by RNA sequencing and bioinformatics analysis. It also aims to provide comprehensive understanding of the differences in muscle fibers in subtropical cattle breeds and to expand the knowledge of the molecular networks that regulate myogenesis. With regard to meat quality indicators, results showed that the longissimus dorsi of LQC had lower pH (P < 0.0001), lower redness (P < 0.01), lower shear force (P < 0.05), and higher brightness (P < 0.05) than the longissimus dorsi of LFC. With regard to muscle fiber characteristics, the longissimus dorsi of LQC had a smaller diameter (P < 0.0001) and higher density of muscle fibers (P < 0.05). The analysis results show that the function of many circRNA-targeted mRNAs was related to myogenesis and metabolic regulation. Furthermore, in the analysis of the function of circRNA source genes, we hypothesized that btacirc_00497 and btacirc_034497 may regulate the function and type of myofibrils by affecting the expression of MYH6, MYH7, and NEB through competitive linear splicing.


Assuntos
Biologia Computacional , RNA Circular , Animais , Bovinos/genética , China , Carne , Músculos Paraespinais
10.
Rheumatology (Oxford) ; 62(5): 1955-1963, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36165706

RESUMO

OBJECTIVES: Long non-coding RNAs (lncRNAs) play important roles in RA pathogenesis. However, specific lncRNAs that regulate gene expression in RA pathogenesis are poorly known. This study was undertaken to characterize a novel lncRNA (lnc-RNU12) that has a lower-than-normal expression level in RA patients. METHODS: We performed initial genome-wide lncRNA microarray screening in peripheral blood mononuclear cells from 28 RA cases and 18 controls. Multiple methods were used to validate the detected associations between lncRNAs and RA. Furthermore, we identified the source and characteristics of the highlighted lncRNAs, detected the target genes, and determined the functional effect on immune cells through lncRNA knock-down in Jurkat T cell lines. RESULTS: lnc-RNU12 was downregulated in peripheral blood mononuclear cells and T cell subtypes of RA patients and was genetically associated with RA risk. lnc-RNU12 mediates the effect of microbiome alterations on RA risk. Activation of T cells caused low expression of lnc-RNU12. Knock-down of lnc-RNU12 in Jurkat T cells caused cell cycle S-phase arrest and altered the expression of protein-coding genes related to the cell cycle and apoptosis (e.g. c-JUN, CCNL2, CDK6, MYC, RNF40, PKM, VPS35, DNAJB6 and FLCN). Finally, c-JUN and CCNL2 were identified as target genes of lnc-RNU12 at the mRNA and protein expression levels. RNA-binding protein immunoprecipitation assays verified the interaction between lnc-RNU12 and the two proteins (c-Jun and cyclin L2) in Jurkat cells. CONCLUSIONS: Our study suggested that lnc-RNU12 was involved in the pathogenesis of RA by influencing the T cell cycle by targeting c-JUN and CCNL2.


Assuntos
Artrite Reumatoide , RNA Longo não Codificante , Humanos , Ciclo Celular , Ciclinas , Proteínas de Choque Térmico HSP40 , Leucócitos Mononucleares/metabolismo , Chaperonas Moleculares , Proteínas do Tecido Nervoso , RNA Longo não Codificante/genética , Linfócitos T/metabolismo , Fatores de Transcrição , Proteínas Proto-Oncogênicas c-jun/metabolismo
11.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37921840

RESUMO

A novel anaerobic heterotrophic bacterium, designated strain SWIR-1T, was isolated from a deep-sea hydrothermal vent field sample collected from the Southwest Indian Ridge at a depth of 2700 m. Phylogenetic analysis indicated that strain SWIR-1T belongs to the genus Tepidibacter, and the most closely related species are Tepidibacter mesophilus B1T (99.1 % 16S rRNA gene sequence similarity), Tepidibacter formicigenes DV1184T (94.6 %) and Tepidibacter thalassicus SC562T (93.9 %). Strain SWIR-1T shares 77.3-87.2 % average nucleotide identity and 21.5-35.7 % digital DNA-DNA hybridization values with the three type strains of Tepidibacter species. Cells of strain SWIR-1T were Gram-stain-positive, motile, short straight rods. Endospores were observed in stationary-phase cells when grown on Thermococcales rich medium. Strain SWIR-1T grew at 15-45 °C (optimum, 30°C), at pH 5.5-8.0 (optimum, pH 7.0) and with 1.0-6.0 % (w/v) NaCl (optimum, 2.0 %). Substrates utilized by strain SWIR-1T included complex proteinaceous, chitin, starch, lactose, maltose, fructose, galactose, glucose, rhamnose, arabinose, ribose, alanine, glycine and glycerol. The major fermentation products from glucose were acetate, lactate, H2 and CO2. Elemental sulphur, sulphate, thiosulphate, sulphite, fumarate, nitrate, nitrite and FeCl3 are not used as terminal electron acceptors. The main cellular fatty acids consisted of iso-C15 : 0 (28.4 %), C15 : 1 iso F (15.4 %) and C16 : 0 (9.8 %). The major polar lipids were phospholipids and glycolipids. No respiratory quinones were detected. Genomic comparison revealed a distinctive blended gene cluster comprising hyb-tat-hyp genes, which play a crucial role in the synthesis, maturation, activation and export of NiFe-hydrogenase. Based on the phylogenetic analysis, genomic, physiologic and chemotaxonomic characteristics, strain SWIR-1T is considered to represent a novel species within the genus Tepidibacter, for which the name Tepidibacter hydrothermalis sp. nov. is proposed. The type strain is strain SWIR-1T (=DSM 113848T=MCCC 1K07078T).


Assuntos
Ácidos Graxos , Fontes Hidrotermais , Ácidos Graxos/química , Filogenia , Anaerobiose , Fontes Hidrotermais/microbiologia , RNA Ribossômico 16S/genética , Composição de Bases , Análise de Sequência de DNA , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Bactérias Anaeróbias , Glucose
12.
Artigo em Inglês | MEDLINE | ID: mdl-37755238

RESUMO

A novel bacterium, strain QS115T, was isolated from deep-sea sediment collected from the South China Sea at a depth of 1151 m. Phylogenetic analyses based on 16S rRNA gene sequences indicated that QS115T was most closely related to Parasedimentitalea marina W43T, with similarity of 98.21 %. Strain QS115T shared 82.39 % average nucleotide identity, 26.3 % digital DNA-DNA hybridization and 85.32 % average amino acid identity with P. marina W43T. Cells of strain QS115T were Gram-stain-negative, rod-shaped and grew optimally at 10 °C, pH 7.5 and 2 % (w/v) NaCl. The principal fatty acids were summed feature 8 (C18 : 1 ω7c/ω6c), the major respiratory quinone was ubiquinone-10 and predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, glycophospholipid, phosphatidylglycerol and phosphatidylcholine. Polyphasic analyses of physiological and phenotypic characteristics and genomic studies suggested that strain QS115T represents a novel species of the genus Parasedimentitalea, for which the name Parasedimentitalea psychrophila sp. nov. is proposed (type strain QS115T=MCCC 1K04395T=JCM 34219T).


Assuntos
Ácidos Graxos , Fosfolipídeos , Ácidos Graxos/química , Fosfolipídeos/química , Água do Mar/microbiologia , DNA Bacteriano/genética , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Composição de Bases , Técnicas de Tipagem Bacteriana , Ubiquinona/química , Bactérias/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-36951905

RESUMO

A novel moderately thermophilic heterotrophic bacterium, designated strain 143-21T, was isolated from a deep-sea hydrothermal chimney sample collected from the Central Indian Ridge at a depth of 2 440 m. Phylogenetic analysis indicated that strain 143-21T belongs to the genus Crassaminicella. It was most closely related to Crassaminicella thermophila SY095T (96.79 % 16S rRNA gene sequence similarity) and Crassaminicella profunda Ra1766HT (96.52 %). Genomic analysis showed that strain 143-21T shares 79.79-84.45 % average nucleotide identity and 23.50-29.20 % digital DNA-DNA hybridization with the species of the genus Crassaminicella, respectively. Cells were rod-shaped, non-motile, Gram-positive-staining. Terminal endospores were observed in stationary-phase cells when strain 143-21T was grown on Thermococcales rich medium. Strain 143-21T was able to grow at 30-60 °C (optimum, 50 °C), pH 6.5-8.5 (optimum, pH 7.0) and in 1.0-7.0 % NaCl (w/v; optimum 2.0 %, w/v). Strain 143-21T utilized fructose, glucose, maltose, mannose, ribose, N-acetyl-d-(+)-glucosamine and casamino acids, as well as amino acids including glutamate, lysine, histidine and cysteine. The main fermentation products from glucose were acetate (2.07 mM), H2 and CO2. It did not reduce elemental sulphur, sulphate, thiosulphate, sulphite, fumarate, nitrate, nitrite and Fe (III). The predominant cellular fatty acids were C14 : 0 (48.8 %), C16 : 0 (12.9 %), and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c; 10.2 %). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol, as well as two unidentified phospholipids and four unidentified aminolipids. No respiratory quinones were detected. Based on its phylogenetic analysis and physiological characteristics, strain 143-21T is considered to represent a novel species of the genus Crassaminicella, for which the name Crassaminicella indica sp. nov. is proposed. The type strain is strain 143-21T (=DSM 114408T= MCCC 1K06400T).


Assuntos
Ácidos Graxos , Fontes Hidrotermais , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , Fontes Hidrotermais/microbiologia , Anaerobiose , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Fosfolipídeos/química , Bactérias Anaeróbias
14.
J Appl Microbiol ; 134(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38066686

RESUMO

AIMS: Magnetotactic bacteria (MTB) can use their unique intracellular magnetosome organelles to swim along the Earth's magnetic field. They play important roles in the biogeochemical cycles of iron and sulfur. Previous studies have shown that the applied magnetic fields could affect the magnetosome formation and antioxidant defense systems in MTB. However, the molecular mechanisms by which magnetic fields affect MTB cells remain unclear. We aim to better understand the dark at 28°C-29°C for 20 h, as shownthe interactions between magnetic fields and cells, and the mechanism of MTB adaptation to magnetic field at molecular levels. METHODS AND RESULTS: We performed microbiological, transcriptomic, and genetic experiments to analyze the effects of a weak static magnetic field (SMF) exposure on the cell growth and magnetosome formation in the MTB strain Magnetospirillum magneticum AMB-1. The results showed that a 1.5 mT SMF significantly promoted the cell growth but reduced magnetosome formation in AMB-1, compared to the geomagnetic field. Transcriptomic analysis revealed decreased expression of genes primarily involved in the sulfate reduction pathway. Consistently, knockout mutant lacking adenylyl-sulfate kinase CysC did no more react to the SMF and the differences in growth and Cmag disappeared. Together with experimental findings of increased reactive oxidative species in the SMF-treated wild-type strain, we proposed that cysC, as a key gene, can participate in the cell growth and mineralization in AMB-1 by SMF regulation. CONCLUSIONS: This study suggests that the magnetic field exposure can trigger a bacterial oxidative stress response involved in AMB-1 growth and magnetosome mineralization by regulating the sulfur metabolism pathway. CysC may serve as a pivotal enzyme in mediating sulfur metabolism to synchronize the impact of SMF on both growth and magnetization of AMB-1.


Assuntos
Magnetossomos , Magnetossomos/genética , Magnetossomos/metabolismo , Sulfatos/metabolismo , Redes e Vias Metabólicas , Enxofre/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
15.
Angew Chem Int Ed Engl ; 62(12): e202218039, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36656994

RESUMO

The chemical selectivity and faradaic efficiency of high-index Cu facets for the CO2 reduction reaction (CO2 RR) is investigated. More specifically, shape-controlled nanoparticles enclosed by Cu {hk0} facets are fabricated using Cu multilayer deposition at three distinct layer thicknesses on the surface facets of Au truncated ditetragonal nanoprisms (Au DTPs). Au DTPs are shapes enclosed by 12 high-index {310} facets. Facet angle analysis confirms DTP geometry. Elemental mapping analysis shows Cu surface layers are uniformly distributed on the Au {310} facets of the DTPs. The 7 nm Au@Cu DTPs high-index {hk0} facets exhibit a CH4 : CO product ratio of almost 10 : 1 compared to a 1 : 1 ratio for the reference 7 nm Au@Cu nanoparticles (NPs). Operando Fourier transform infrared spectroscopy spectra disclose reactive adsorbed *CO as the main intermediate, whereas CO stripping experiments reveal the high-index facets enhance the *CO formation followed by rapid desorption or hydrogenation.

16.
Zhongguo Yi Liao Qi Xie Za Zhi ; 47(1): 70-73, 2023 Jan 30.
Artigo em Chinês | MEDLINE | ID: mdl-36752010

RESUMO

OBJECTIVE: To discuss the development of a multifunctional and multipoint fixed support drainage device for the digestive tract, as well as the effect of its application on animal experimental models and patients. METHODS: The digestive tract multifunctional and multipoint fixed support drainage device is designed according to the requirements of the various gastrointestinal surgery and interventional procedures. It has metal flaps and airbags to achieve multi point fixation. The cuffs and shears are used to achieve endoscopic removal. And through different tube diameters and lengths, surgeons can achieve different surgical purposes. RESULTS: A multifunctional and multipoint fixed support drainage device for the digestive tract was successfully designed and developed. The application experiment of the winged pancreatico-intestinal supporting drainage tube on animal models and patients, showed lower drainage fluid amylase level, faster amylase recovery speed, and better perioperative safety. CONCLUSIONS: The support drainage device has the characteristics of simple operation, firm fixation, and good controllability of removal. It is an ideal choice among support drainage tubes in gastrointestinal surgery and interventional operations.


Assuntos
Drenagem , Trato Gastrointestinal , Endoscopia
17.
J Am Chem Soc ; 144(30): 13920-13927, 2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35880790

RESUMO

The first ribozymes are thought to have emerged at a time when RNA replication proceeded via nonenzymatic template copying processes. However, functional RNAs have stable folded structures, and such structures are much more difficult to copy than short unstructured RNAs. How can these conflicting requirements be reconciled? Also, how can the inhibition of ribozyme function by complementary template strands be avoided or minimized? Here, we show that short RNA duplexes with single-stranded overhangs can be converted into RNA stem loops by nonenzymatic cross-strand ligation. We then show that loop-closing ligation reactions enable the assembly of full-length functional ribozymes without any external template. Thus, one can envisage a potential pathway whereby structurally complex functional RNAs could have formed at an early stage of evolution when protocell genomes might have consisted only of collections of short replicating oligonucleotides.


Assuntos
RNA Catalítico , Conformação de Ácido Nucleico , Oligonucleotídeos/metabolismo , RNA/química , RNA Catalítico/química
18.
J Am Chem Soc ; 144(33): 15047-15058, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35951390

RESUMO

Oxide-derived copper electrodes have displayed a boost in activity and selectivity toward valuable base chemicals in the electrochemical carbon dioxide reduction reaction (CO2RR), but the exact interplay between the dynamic restructuring of copper oxide electrodes and their activity and selectivity is not fully understood. In this work, we have utilized time-resolved surface-enhanced Raman spectroscopy (TR-SERS) to study the dynamic restructuring of the copper (oxide) electrode surface and the adsorption of reaction intermediates during cyclic voltammetry (CV) and pulsed electrolysis (PE). By coupling the electrochemical data to the spectral features in TR-SERS, we study the dynamic activation of and reactions on the electrode surface and find that CO2 is already activated to carbon monoxide (CO) during PE (10% Faradaic efficiency, 1% under static applied potential) at low overpotentials (-0.35 VRHE). PE at varying cathodic bias on different timescales revealed that stochastic CO is dominant directly after the cathodic bias onset, whereas no CO intermediates were observed after prolonged application of low overpotentials. An increase in cathodic bias (-0.55 VRHE) resulted in the formation of static adsorbed CO intermediates, while the overall contribution of stochastic CO decreased. We attribute the low-overpotential CO2-to-CO activation to a combination of selective Cu(111) facet exposure, partially oxidized surfaces during PE, and the formation of copper-carbonate-hydroxide complex intermediates during the anodic pulses. This work sheds light on the restructuring of oxide-derived copper electrodes and low-overpotential CO formation and highlights the power of the combination of electrochemistry and time-resolved vibrational spectroscopy to elucidate CO2RR mechanisms.

19.
Mol Cell Biochem ; 477(2): 455-468, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34783964

RESUMO

SNP rs3755955 (major/minor allele: G/A) located in Iduronidase-Alpha-L- (IDUA) gene was reported to be significant for human bone mineral density (BMD). This follow-up study was to uncover the underlying association mechanism through molecular and cellular functional assays relevant to bone. We tested the effects of single nucleotide polymorphisms (SNP) rs3755955 (defined allele G as wild-type and allele A as variant-type) on osteoblastic and osteoclastic functions, as well as protein phosphorylation in stably transfected human fetal osteoblast (hFOB) cell and mononuclear-macrophage (RAW264.7) cell. In hFOB cells, transfection with variant-type IDUA significantly decreased osteoblastic gene expression (OPN, COL1A1 and RANKL) (p < 0.01), impeded cell proliferation (p < 0.05), stimulated cell apoptosis (p < 0.001) and decreased ALP enzyme activity, as compared with that of wild-type IDUA transfection. In RAW264.7 cells, transfection with variant-type IDUA significantly inhibited cell apoptosis (p < 0.01), promoted osteoclastic precursor cell migration (p < 0.0001), growth (p < 0.01), osteoclastic gene expression (TRAP, RANK, Inte-αv and Cath-K) (p < 0.05) and TRAP enzyme activity (p < 0.001), as compared with that of wild-type IDUA transfection. In both hFOB and RAW264.7 cells, the total protein and IDUA protein-specific phosphorylation levels were significantly reduced by variant IDUA transfection, as compared with that of wild-type IDUA transfection (p < 0.05). Variant allele A of phosSNP rs3755955 in IDUA gene regulates protein phosphorylation, inhibits osteoblast function and promotes osteoclastic activity. The SNP rs3755955 could alter IDUA protein phosphorylation, significantly regulates human osteoblastic and osteoclastic gene expression, and influences the growth, differentiation and activity of osteoblast and osteoclast, hence to affect BMD.


Assuntos
Densidade Óssea/genética , Regulação da Expressão Gênica , Osteoblastos/metabolismo , Polimorfismo de Nucleotídeo Único , Animais , Humanos , Camundongos , Células RAW 264.7
20.
Surg Endosc ; 36(6): 4090-4098, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34518951

RESUMO

BACKGROUND: The thrombosis of the main and intrahepatic branches of the portal vein (TMIP) is potentially lethal and deemed a common complication following laparoscopic splenectomy and azygoportal disconnection (LSD) in patients with cirrhosis and portal hypertension (PH). The predictors of TMIP after LSD remain unclear. The aim of this prospective study was to explore the predictive and risk factors for TMIP after LSD in cirrhotic patients with PH caused only by hepatitis B virus. METHODS: From September 2014 to March 2017, we enrolled 115 patients with hepatitis B cirrhosis and PH who successfully underwent LSD. Patients were subdivided into a TMIP group and a non-TMIP group. Univariate and multivariate logistic regression analysis was conducted on 24 items of demographic and preoperative data, to explore the risk factors of TMIP. RESULTS: Twenty-nine (25.22%) patients developed TMIP on postoperative day (POD) 7 and 26 (22.81%) patients developed TMIP on POD 30. From POD 7 to POD 30, 12 patients who did not have TMIP at POD 7 were newly diagnosed with TMIP, with portal vein diameter 15.05 ± 2.58 mm. Another 14 patients in whom TMIP had resolved had portal vein diameter 14.02 ± 1.76 mm. Univariate analysis and multivariate logistic regression revealed that portal vein diameter ≥ 13 mm [relative risk (RR) 5.533, 95% confidence interval (CI) 1.222-25.042; P = 0.026] and portal vein diameter ≥ 15 mm (RR 3.636, 95% CI 1.466-9.021; P = 0.005) were significant independent risk factors for TMIP on POD 7 and 30, respectively. CONCLUSION: Portal vein diameter ≥ 13 mm and ≥ 15 mm were significant independent predictors for TMIP after LSD in patients with hepatitis B cirrhosis and PH on POD 7 and POD 30, respectively. TRIAL REGISTRATION: We registered our research at https://www. CLINICALTRIALS: gov/ . The name of research registered is "Warfarin Prevents Portal Vein Thrombosis in Patients After Laparoscopic Splenectomy and Azygoportal Disconnection." The trial registration identifier at clinicaltrials.gov is NCT02247414.


Assuntos
Hepatite B , Hipertensão Portal , Laparoscopia , Trombose Venosa , Humanos , Hepatite B/complicações , Hepatite B/cirurgia , Hipertensão Portal/complicações , Hipertensão Portal/cirurgia , Laparoscopia/efeitos adversos , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia , Veia Porta/cirurgia , Estudos Prospectivos , Esplenectomia/efeitos adversos , Trombose Venosa/etiologia , Trombose Venosa/prevenção & controle
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