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1.
J Mol Cell Cardiol ; 193: 36-52, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38795767

RESUMO

BACKGROUND: Atherosclerosis is a chronic pathology, leading to acute coronary heart disease or stroke. MiR-127 has been found significantly upregulated in advanced atherosclerosis. But its function in atherosclerosis remains unexplored. We explored the role of miR-127-3p in regulating atherosclerosis development and its downstream mechanisms. METHODS: The expression profile of miR-127 in carotid atherosclerotic plaques of 23 patients with severe carotid stenosis was detected by RT-qPCR and in situ hybridization. Primary bone marrow-derived macrophages (BMDM) stimulated with oxidized low-density lipoprotein were used as an in vitro model. CCK-8, EdU, RT-qPCR, and flow cytometry were used to detect the proliferative capacity and polarization of BMDM, which were infected by lentivirus-carrying plasmid to upregulate or downregulate miR-127-3p expression, respectively. RNA sequencing combined with bioinformatic analysis and targeted fatty acid metabolomics approach were used to detect the transcriptome and lipid metabolites. The association between miR-127-3p and its target was verified by dual-luciferase activity reporting and Western blotting. Oxygen consumption rate of BMDM were detected using seahorse analysis. High-cholesterol-diet-fed low density lipoprotein deficient (LDLR-/-) mice, with-or-without carotid tandem-stenosis surgery, were treated with miR-127-3p agomir or antagomir to examine its effect on plaque development and stability. RESULTS: miR-127-3p, not -5p, is elevated in human advanced carotid atheroma and its expression is positively associated with macrophage accummulation in plaques. In vitro, miR-127-3p-overexpressed macrophage exhibites increased proliferation capacity and facilitates M1 polariztion whereas the contrary trend is present in miR-127-3p-inhibited macrophage. Stearoyl-CoA desaturase-1 (SCD1) is one potential target of miR-127-3p. miR-127-3p mimics decreases the activity of 3' untranslated regions of SCD-1. Furthermore, miR-127-3p downregulates SCD1 expression, and reversing the expression of SCD1 attenuates the increased proliferation induced by miR-127-3p overexpression in macrophage. miR-127-3p overexpression could also lead to decreased content of unsaturated fatty acids (UFAs), increased content of acetyl CoA and increased level of oxidative phosphorylation. In vivo, miR-127-3p agomir significantly increases atherosclerosis progression, macrophage proliferation and decreases SCD1 expression and the content of UFAs in aortic plaques of LDLR-/- mice. Conversely, miR-127-3p antagomir attenuated atherosclerosis, macrophage proliferation in LDLR-/- mice, and enhanced carotid plaque stability in mice with vulnerable plaque induced. CONCLUSION: MiR-127-3p enhances proliferation in macrophages through downregulating SCD-1 expression and decreasing the content of unsaturated fatty acid, thereby promoting atherosclerosis development and decreasing plaque stability. miR-127-3p/SCD1/UFAs might provide potential therapeutic target for anti-inflammation and atherosclerosis.

2.
J Am Chem Soc ; 146(26): 17765-17772, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38902874

RESUMO

Chirality, a fundamental attribute of nature, significantly influences a wide range of phenomena related to physical properties, chemical reactions, biological pharmacology, and so on. As a pivotal aspect of chirality research, chirality recognition contributes to the synthesis of complex chiral products from simple chiral compounds and exhibits intricate interplay between chiral materials. However, macroscopic detection technologies cannot unveil the dynamic process and intrinsic mechanisms of single-molecule chirality recognition. Herein, we present a single-molecule detection platform based on graphene-molecule-graphene single-molecule junctions to measure the chirality recognition involving interactions between amines and chiral alcohols. This approach leads to the realization of in situ and real-time direct observation of chirality recognition at the single-molecule level, demonstrating that chiral alcohols exhibit compelling potential to induce the formation of the corresponding chiral configuration of molecules. The amalgamation of theoretical analyses with experimental findings reveals a synergistic action between electrostatic interactions and steric hindrance effects in the chirality recognition process, thus substantiating the microscopic mechanism governing the chiral structure-activity relationship. These studies open up a pathway for exploring novel chiral phenomena from the fundamental limits of chemistry, such as chiral origin and chiral amplification, and offer important insights into the precise synthesis of chiral materials.

3.
J Am Chem Soc ; 144(45): 20797-20803, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36274261

RESUMO

The PNP structure realized by energy band engineering is widely used in various electronic and optoelectronic devices. In this work, we succeed in constructing a PNP-type single-molecule junction and explore the intrinsic characteristics of the PNP structure at the single-molecule level. A back-to-back azulene molecule is designed with opposite ∼1.7 D dipole moments to create PNP-type single-molecule junctions. In combination with theoretical and experimental studies, it is found that the intrinsic dipole can effectively adjust single-molecule charge transport and the corresponding potential barriers. This energy band control and charge transport regulation at the single-molecule level improve deep understanding of molecular charge transport mechanisms and provide important insights into the development of high-performance functional molecular nanocircuits toward practical applications.


Assuntos
Eletrônica , Nanotecnologia
4.
J Infect Dis ; 222(6): 1008-1020, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32274497

RESUMO

BACKGROUND: Leptospirosis is a global zoonotic infectious disease caused by Leptospira interrogans. The pathogen rapidly invades into hosts and diffuses from bloodstream into internal organs and excretes from urine to cause transmission of leptospirosis. However, the mechanism of leptospiral invasiveness remains poorly understood. METHODS: Proteolytic activity of M16-type metallopeptidases (Lep-MP1/2/3) of L. interrogans was determined by spectrophotometry. Expression and secretion of Lep-MP1/2/3 during infection of cells were detected by quantitative reverse-transcription polymerase chain reaction, Western blot assay, and confocal microscopy. Deletion and complementation mutants of the genes encoding Lep-MP1/2/3 were generated to determine the roles of Lep-MP1/2/3 in invasiveness using transwell assay and virulence in hamsters. RESULTS: Leptospira interrogans but not saprophytic Leptospira biflexa strains were detectable for Lep-MP-1/2/3-encoding genes. rLep-MP1/2/3 hydrolyzed extracellular matrix proteins, but rLep-MP1/3 displayed stronger proteolysis than rLep-MP2, with 123.179/340.136 µmol/L Km and 0.154/0.159 s-1 Kcat values. Expression, secretion and translocation of Lep-MP1/2/3 during infection of cells were increased. ΔMP1/3 but not ΔMP2 mutant presented attenuated transmigration through cell monolayers, decreased leptospiral loading in the blood, lungs, liver, kidneys, and urine, and 10/13-fold decreased 50% lethal dose and milder histopathologic injury in hamsters. CONCLUSIONS: Lep-MP1 and 3 are involved in virulence of L. interrogans in invasion into hosts and diffusion in vivo, and transmission of leptospirosis.


Assuntos
Leptospira interrogans/classificação , Leptospira interrogans/genética , Leptospirose/microbiologia , Leptospirose/transmissão , Metaloproteases/genética , Animais , Carga Bacteriana , Biópsia , Cricetinae , Modelos Animais de Doenças , Ativação Enzimática , Regulação Bacteriana da Expressão Gênica , Leptospira interrogans/enzimologia , Leptospira interrogans/patogenicidade , Leptospirose/patologia , Masculino , Metaloproteases/metabolismo , Mutação , Proteólise , Coelhos , Virulência/genética , Fatores de Virulência/genética
5.
Mol Microbiol ; 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29633391

RESUMO

Leptospira spp. comprise both pathogenic and free-living saprophytic species. Little is known about the environmental adaptation and survival mechanisms of Leptospira. Alternative sigma factor, σ54 (RpoN) is known to play an important role in environmental and host adaptation in many bacteria. In this study, we constructed an rpoN mutant by allele exchange, and the complemented strain in saprophytic L. biflexa. Transcriptome analysis revealed that expression of several genes involved in nitrogen uptake and metabolism, including amtB1, glnB-amtB2, ntrX and narK, were controlled by σ54 . While wild-type L. biflexa could not grow under nitrogen-limiting conditions but was able to survive under such conditions and recover rapidly, the rpoN mutant was not. The rpoN mutant also had dramatically reduced ability to survive long-term in water. σ54 appears to regulate expression of amtB1, glnK-amtB2, ntrX and narK in an indirect manner. However, we identified a novel nitrogen-related gene, LEPBI_I1011, whose expression was directly under the control of σ54 (herein renamed as rcfA for RpoN-controlled factor A). Taken together, our data reveal that the σ54 regulatory network plays an important role in the long-term environmental survival of Leptospira spp.

6.
Appl Environ Microbiol ; 83(3)2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27864172

RESUMO

Leptospira interrogans is the agent of leptospirosis, a reemerging zoonotic disease. It is transmitted to humans through environmental surface waters contaminated by the urine of mammals chronically infected by pathogenic strains able to survive in water for long periods. Little is known about the regulatory pathways underlying environmental sensing and host adaptation of L. interrogans during its enzootic cycle. This study identifies the EbpA-RpoN regulatory pathway in L. interrogans In this pathway, EbpA, a σ54 activator and putative prokaryotic enhancer-binding protein (EBP), and the alternative sigma factor RpoN (σ54) control expression of at least three genes, encoding AmtB (an ammonium transport protein) and two proteins of unknown function. Electrophoresis mobility shift assay demonstrated that recombinant RpoN and EbpA bind to the promoter region and upstream of these three identified genes, respectively. Genetic disruption of ebpA in L. interrogans serovar Manilae virtually abolished expression of the three genes, including amtB in two independent ebpA mutants. Complementation of the ebpA mutant restored expression of these genes. Intraperitoneal inoculation of gerbils with the ebpA mutant did not affect mortality. However, the ebpA mutant had decreased cell length in vitro and had a significantly lowered cell density at stationary phase when grown with l-alanine as the sole nitrogen source. Furthermore, the ebpA mutant has dramatically reduced long-term survival ability in water. Together, these studies identify a regulatory pathway, the EbpA-RpoN pathway, that plays an important role in the zoonotic cycle of L. interrogans IMPORTANCE: Leptospirosis is a reemerging disease with global importance. However, our understanding of gene regulation of the spirochetal pathogen Leptospira interrogans is still in its infancy, largely due to the lack of robust tools for genetic manipulation of this spirochete. Little is known about how the pathogen achieves its long-term survival in the aquatic environment. By utilizing bioinformatic, genetic, and biochemical methods, we discovered a regulatory pathway in L. interrogans, the EbpA-RpoN pathway, and demonstrated that this pathway plays an important role in environmental survival of this pathogen.


Assuntos
Proteínas de Bactérias/genética , Meio Ambiente , Regulação Bacteriana da Expressão Gênica , Leptospira interrogans/genética , Fator sigma/genética , Proteínas de Bactérias/metabolismo , Leptospira interrogans/metabolismo , Fator sigma/metabolismo
7.
Aging Clin Exp Res ; 28(2): 181-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26197716

RESUMO

OBJECTIVES: The mechanisms for pathogenesis of cardiac valve calcification were explored by studying the regulation of the Wnt signaling pathway during the transformation from cardiac valvular myofibroblasts to osteoblast-like phenotype. METHODS: Studies were carried on primary cultured porcine aortic valvular myofibroblasts. The cells were randomly divided into four groups and treated with angiotensin II (Ang II) according to the following: Ang II (10(-6) mol/l), Valsartan (Val) (10(-5) mol/l), Ang II plus Val (Ang II 10(-6) mol/l + Val 10(-5) mol/l) or mock treated as the control. Protein expression of Bone morphogenetic protein 2 (BMP2), Alkaline phosphatase (ALP), and Wnt pathway components, Wnt3a and ß-catenin, was investigated to assess the activation of the Wnt signaling pathway and determine whether cells undergo the transformation to osteoblast-like phenotype. RESULT: Ang II treatment of myofibroblasts led to significant up-regulation of α-SMA expression and activation of the cells. Neither the BMP2 or ALP proteins, nor the mRNA was detectable in the control group or the Val-treated group; however, there was a significant increase in Ang II-treated group (P < 0.01). The Wnt/ß-catenin signaling ligand, Wnt3a, was not expressed in the control or Val-treated groups, whereas in Ang II-treated cells, both Wnt3a and ß-catenin gene expression were enhanced (P < 0.01).The effect of Ang II can be inhibited by the addition of Val (P < 0.05). CONCLUSION: Ang II might act on the Ang II receptor on valvular interstitial cells (VICs) and lead to activation of the Wnt/ß-catenin pathway and hence cause the activation, differentiation and proliferation of myofibroblasts, and finally, osteoblast-like phenotype transformation, leading to calcification of heart valves.


Assuntos
Angiotensina II , Valva Aórtica/patologia , Calcinose/metabolismo , Transdiferenciação Celular/efeitos dos fármacos , Miofibroblastos , Osteoblastos/fisiologia , Valsartana/farmacologia , Via de Sinalização Wnt , Actinas/metabolismo , Fosfatase Alcalina/metabolismo , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Proteína Morfogenética Óssea 2/metabolismo , Células Cultivadas , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Fenótipo , Suínos , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/fisiologia
8.
J Heart Valve Dis ; 24(2): 190-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26204684

RESUMO

BACKGROUND AND AIM OF THE STUDY: Calcific aortic valve disease (CAVD) is a commonly acquired valvular disease. Although previous studies have shown valve calcification to be mediated by a chronic inflammatory disease process, with many similarities to atherosclerosis that included inflammatory cell infiltrates, lipoproteins, lipids, extracellular bone-matrix proteins, and bone minerals, little is known of the mechanisms of the cellular and molecular components and processes. It has recently been hypothesized that the calcific aortic valve is a product of active inflammation, similar to the atherosclerosis pathological process. Thus, the cessation of statin therapy should, in theory, have an effect on the treatment of CAVD and on aortic valve myofibroblasts (AVMFs), which play an important role in aortic valvular calcification. The study aim was to determine if oxidized low-density lipoprotein (oxLDL) could stimulate the apoptosis of AVMFs and the calcific-related pathway, and whether atorvastatin could inhibit the effects of AVMFs induced by oxLDL. The Wnt/GSK-3ß/ß-catenin signaling pathway may play a key role in this process, thereby making a major contribution to aortic valve calcification. METHODS: AVMFs were successfully acquired using a combination of trypsin and collagenase enzyme digestion, and made phenotypic for the identification for alpha-smooth muscle actin (α-SMA). Cell apoptosis was monitored using flow cytometry, bone protein expression by Western blot, and related gene expression by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: A positive identification of α-SMA, a myofibroblast marker, confirmed the successful harvesting of myofibroblasts. OxLDL significantly induced cell apoptosis (p < 0.05), and this became even more obvious after 48 h (p < 0.01). OxLDL also significantly increased the protein expression of all differentiation markers (p < 0.05), as confirmed through Western blotting and RT-PCR, while atorvastatin significantly reduced the effects of oxLDL (p < 0.05). CONCLUSION: Among the mechanisms of the cellular and molecular components and processes, oxLDL increased the valve calcification-related signaling pathway by increasing extracellular bone-matrix protein that produces osteoblastic gene markers via the Wnt/GSK-3ß/ß-catenin pathway. And atorvastatin also prevented any oxLDL-induced effects through the same pathway, this may represent a new therapeutic target for CAVD, as an alternative to traditional valve replacement surgery.


Assuntos
Apoptose/efeitos dos fármacos , Calcinose/fisiopatologia , Cardiopatias Congênitas/fisiopatologia , Doenças das Valvas Cardíacas/fisiopatologia , Lipoproteínas LDL/farmacologia , Miofibroblastos/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Valva Aórtica/patologia , Valva Aórtica/fisiopatologia , Atorvastatina , Doença da Válvula Aórtica Bicúspide , Western Blotting , Células Cultivadas , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Miofibroblastos/fisiologia , Pirróis/farmacologia , Suínos , Via de Sinalização Wnt/fisiologia
9.
J Infect Dis ; 209(7): 1105-15, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24277745

RESUMO

BACKGROUND: Leptospirosis is a global zoonotic disease. Transmission of Leptospira from animals to humans occurs through contact with water contaminated with leptospire-containing urine of infected animals. However, the molecular basis for the invasiveness of Leptospira and transmission of leptospirosis remains unknown. METHODS: Activity of Leptospira interrogans strain Lai colA gene product (ColA) to hydrolyze different collagenic substrates was determined by spectrophotometry. Expression and secretion of ColA during infection were detected by reverse-transcription quantitative polymerase chain reaction and Western blot assay. The colA gene-deleted (ΔcolA) and colA gene-complemented (CΔcolA) mutants were generated to determine the roles of ColA in transcytosis in vitro and virulence in hamsters. RESULTS: Recombinant or native ColA hydrolyzed all the tested substrates in which type III collagen was the favorite substrate with 2.16 mg/mL Km and 35.6 h(-)(1) Kcat values. Coincubation of the spirochete with HUVEC or HEK293 cells directly caused the significant elevation of ColA expression and secretion. Compared with wild-type strain, ΔcolA mutant displayed much-attenuated transcytosis through HEK293 and HUVEC monolayers, and less leptospires in blood, lung, liver, kidney and urine and 25-fold-decreased 50% lethal dose and milder histopathological injury in hamsters. CONCLUSIONS: The product of colA gene is a collagenase as a crucial virulence factor in the invasiveness and transmission of L. interrogans.


Assuntos
Colagenases/metabolismo , Leptospira interrogans/enzimologia , Leptospira interrogans/patogenicidade , Fatores de Virulência/metabolismo , Animais , Western Blotting , Linhagem Celular , Colágeno/metabolismo , Colagenases/genética , Cricetinae , Modelos Animais de Doenças , Células Endoteliais/microbiologia , Fibroblastos/microbiologia , Deleção de Genes , Perfilação da Expressão Gênica , Teste de Complementação Genética , Humanos , Hidrólise , Leptospirose/microbiologia , Leptospirose/patologia , Masculino , Mesocricetus , Reação em Cadeia da Polimerase em Tempo Real , Transcitose , Virulência , Fatores de Virulência/genética
10.
Zhongguo Zhong Yao Za Zhi ; 40(18): 3636-43, 2015 Sep.
Artigo em Zh | MEDLINE | ID: mdl-26983213

RESUMO

Aortic valve calcification (AVC) is a pathological process correlated with multiple disease causes and actively regulated by cardiac valve cells. In this study, porcine aortic valve myofibroblasts cultured in vitro were treated with 50 µg z L(-1) of pathological factor tumor necrosis factor α (TNF-α). Tanshinone II A (TSN) with the concentration of 50 mg x L(-1) and TNF-α were combined in incubating cells for 72 h (3 d) and 120 h (5 d). The Western blotting and Real-time PCR were adopted to detect the changes in smooth muscle α actin (α-SMA), bone morphogenetic protein 2 ( BMP2), alkaline phosphatase (ALP) in cells, and expressions of key effect proteins GSK-3ß and ß-catenin on Wnt/ß-catenin signal pathway. According to the findings, TNF-α can significantly increase the expression of myofibroblasts α-SMA and add the transformation activity to them, with nearly no expression of BMP2, ALP and mRNA in the control group and the TSN group but significant increase in their expressions in the TNF-α group (P < 0.01), which showed osteoblast-like phenotype. Moreover, TNF-α down-regulated the expression of up-streaming regulator GSK-3ß and mRNA expression (P < 0. 01) , notably increased the expression of key effect protein ß-catenin, but with no significant difference in mRNA with the control group and the TSN group. The result demonstrated that TSN showed a certain inhibitory effect on TNF-α's pathological impact (P < 0.05) in a time-dependent manner. Inflammatory factor TNF-α may promote the transformation of aortic valvular myofibroblasts to osteoblast-like phenotype by activating Wnt/ß-catenin signal pathway in aortic valvular myofibroblasts, so as to cause AVC. Tanshinone II A can have a preventive effect in AVC by activating GSK-3ß proteins and regulating signal transduction of Wnt/ß-catenin signal pathway.


Assuntos
Abietanos/farmacologia , Valva Aórtica/citologia , Medicamentos de Ervas Chinesas/farmacologia , Miofibroblastos/citologia , Osteoblastos/citologia , Animais , Valva Aórtica/efeitos dos fármacos , Valva Aórtica/metabolismo , Células Cultivadas , Quinase 3 da Glicogênio Sintase/genética , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Suínos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
11.
Curr Opin Infect Dis ; 27(5): 432-6, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25061933

RESUMO

PURPOSE OF REVIEW: In this review, we introduce the epidemiological features, clinical types, laboratory diagnosis, and routine surveillance of leptospirosis in China. RECENT FINDINGS: Leptospirosis has been prevalent sporadically in China in recent years, but its incidence has decreased, probably due to the lower leptospire-carrying rate in pigs. Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai is the most common pathogen in Chinese leptospirosis patients and Apodemus agrarius is its major animal host. At least 75% of Chinese leptospirosis patients suffer from the mild influenza-like type of leptospirosis that is caused by any serovars of L. interrogans. However, leptospirosis patients with the pulmonary diffuse hemorrhagic type have a high mortality (40-60%). L. interrogans serovar Lai is the causative agent in 75% of the pulmonary diffuse hemorrhagic leptospirosis patients. Several outer membrane protein antigens exist in all the L. interrogans serovars prevailing in China and predominant T- and B-cell combined epitopes in the outer membrane protein antigens have been identified that can be used for developing novel universal leptospirosis vaccines. SUMMARY: Leptospirosis cases in the Chinese population have gradually decreased in recent years, but it is still an important zoonotic infectious disease. The development of universal vaccines is critical for the prevention and control of leptospirosis.


Assuntos
Surtos de Doenças/prevenção & controle , Leptospira/isolamento & purificação , Leptospirose/diagnóstico , Vacinas de DNA/administração & dosagem , Vacinas Sintéticas/administração & dosagem , Zoonoses/diagnóstico , Fatores Etários , Animais , Animais Domésticos , Animais Selvagens , China/epidemiologia , Clima , Cães , Humanos , Incidência , Leptospira/classificação , Leptospira/imunologia , Leptospira interrogans/isolamento & purificação , Leptospirose/epidemiologia , Leptospirose/imunologia , Leptospirose/prevenção & controle , Vigilância da População , Prevalência , Ratos , Estações do Ano , Fatores Sexuais , Suínos , Vacinação , Zoonoses/epidemiologia , Zoonoses/prevenção & controle
12.
Cell Microbiol ; 15(10): 1642-59, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23521874

RESUMO

Pathogenic Leptospira species, the causative agents of leptospirosis, have been shown to induce macrophage apoptosis through caspase-independent, mitochondrion-related apoptosis inducing factor (AIF) and endonuclease G (EndoG), but the signalling pathway leading to AIF/EndoG-based macrophage apoptosis remains unknown. Here we show that infection of Leptospira interrogans caused a rapid increase in reactive oxygen species (ROS), DNA damage, and intranuclear foci of 53BP1 and phosphorylation of H2AX (two DNAdamage indicators) in wild-type p53-containing mouse macrophages and p53-deficient human macrophages. Most leptospire-infected cells stayed at the G1 phase, whereas depletion or inhibition of p53 caused a decrease of the G1 -phase cells and the early apoptotic ratios. Infection with spirochaetes stimulated a persistent activation of p53 and an early activation of Akt through phosphorylation. The intranuclear translocation of p53, increased expression of p53-dependent p21(Cip) (1/) (WAF) (1) and pro-apoptotic Bcl-2 family proteins (Bax, Noxa and Puma), release of AIF and EndoG from mitochondria, and membrane translocation of Fas occurred during leptospire-induced macrophage apoptosis. Thus, our study demonstrated that ROS production and DNA damage-dependent p53-Bax/Noxa/Puma-AIF/EndoG signalling mediates the leptospire-induced cell cycle arrest and caspase-independent apoptosis of macrophages.


Assuntos
Apoptose , Pontos de Checagem do Ciclo Celular , Interações Hospedeiro-Patógeno , Leptospira interrogans/fisiologia , Macrófagos/microbiologia , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo , Animais , Fator de Indução de Apoptose/metabolismo , Células Cultivadas , Dano ao DNA , Endodesoxirribonucleases/metabolismo , Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Macrófagos/fisiologia , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/toxicidade , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
13.
Pediatr Pulmonol ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837645

RESUMO

OBJECTIVE: This investigation aimed to delineate the clinical manifestations associated with high-altitude pulmonary edema (HAPE) and acute mountain sickness (AMS) in pediatric populations and find the risk factors of HAPE. METHODS: We conducted a retrospective analysis of clinical data from children under 18 years diagnosed with HAPE and AMS at an average altitude of 3000 m. The clinical data between these two groups were compared. RESULTS: The study encompassed 74 pediatric patients, 27 with AMS and 47 with HAPE. HAPE presentations included classic HAPE (55.3%), reentry HAPE (27.7%), and high-altitude resident pulmonary edema (HARPE, 17.0%). Notably, 87.2% of HAPE cases were male, and 68.1% had a high body mass index (BMI). HARPE instances followed viral infections, prominently SARS-CoV-2. HAPE cases exhibited higher BMI, respiratory tract infections within 1 week preceding symptom onset, an increase in white blood cell counts (WBCs), lower peripheral arterial oxygen saturation (SpO2), and higher heart rate compared to the AMS group. Multivariate logistic regression pinpointed high BMI as an independent HAPE risk factor (odds ratio = 19.389, 95% confidence interval: 1.069-351.759, p = .045). CONCLUSION: HAPE occurs predominantly in males, with high BMI identified as a critical independent risk factor. The study underscores the need for heightened awareness and preventive strategies against HAPE in children at high altitudes.

14.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 42(2): 156-63, 2013 03.
Artigo em Zh | MEDLINE | ID: mdl-23585001

RESUMO

OBJECTIVE: To determine expression changes of major outer membrane protein(OMP) antigens of Leptospira interrogans serogroup Icterohaemorrhagiae serovar Lai strain Lai during infection of human macrophages and its mechanism. METHODS: OmpR encoding genes and OmpR-related histidine kinase (HK) encoding gene of L.interrogans strain Lai and their functional domains were predicted using bioinformatics technique. mRNA level changes of the leptospiral major OMP-encoding genes before and after infection of human THP-1 macrophages were detected by real-time fluorescence quantitative RT-PCR. Effects of the OmpR-encoding genes and HK-encoding gene on the expression of leptospiral OMPs during infection were determined by HK-peptide antiserum block assay and closantel inhibitive assays. RESULTS: The bioinformatics analysis indicated that LB015 and LB333 were referred to OmpR-encoding genes of the spirochete, while LB014 might act as a OmpR-related HK-encoding gene. After the spirochete infecting THP-1 cells, mRNA levels of leptospiral lipL21, lipL32 and lipL41 genes were rapidly and persistently down-regulated (P <0.01), whereas mRNA levels of leptospiral groEL, mce, loa22 and ligB genes were rapidly but transiently up-regulated (P<0.01). The treatment with closantel and HK-peptide antiserum partly reversed the infection-based down-regulated mRNA levels of lipL21 and lipL48 genes (P <0.01). Moreover, closantel caused a decrease of the infection-based up-regulated mRNA levels of groEL, mce, loa22 and ligB genes (P <0.01). CONCLUSION: Expression levels of L.interrogans strain Lai major OMP antigens present notable changes during infection of human macrophages. There is a group of OmpR-and HK-encoding genes which may play a major role in down-regulation of expression levels of partial OMP antigens during infection.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Leptospira interrogans/imunologia , Lipoproteínas/metabolismo , Macrófagos/microbiologia , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/genética , Linhagem Celular , Chaperonina 60/genética , Chaperonina 60/metabolismo , Humanos , Leptospira interrogans/genética , Leptospira interrogans/patogenicidade , Lipoproteínas/genética
15.
Nanomicro Lett ; 15(1): 211, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37698706

RESUMO

Chirality, as the symmetric breaking of molecules, plays an essential role in physical, chemical and especially biological processes, which highlights the accurate distinction among heterochiralities as well as the precise preparation for homochirality. To this end, the well-designed structure-specific recognizer and catalysis reactor are necessitated, respectively. However, each kind of target molecules requires a custom-made chiral partner and the dynamic disorder of spatial-orientation distribution of molecules at the ensemble level leads to an inefficient protocol. In this perspective article, we developed a universal strategy capable of realizing the chirality detection and control by the external symmetry breaking based on the alignment of the molecular frame to external stimuli. Specifically, in combination with the discussion about the relationship among the chirality (molecule), spin (electron) and polarization (photon), i.e., the three natural symmetry breaking, single-molecule junctions were proposed to achieve a single-molecule/event-resolved detection and synthesis. The fixation of the molecular orientation and the CMOS-compatibility provide an efficient interface to achieve the external input of symmetry breaking. This perspective is believed to offer more efficient applications in accurate chirality detection and precise asymmetric synthesis via the close collaboration of chemists, physicists, materials scientists, and engineers.

16.
Int J Infect Dis ; 135: 118-122, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37611798

RESUMO

From December 2022 to January 2023, seven children aged ≤14 years and residing in an area at 2999 m without altitude change in the past month developed severe cough, dyspnea, cyanosis, and severe pulmonary lesions within 2-3 days after SARS-CoV-2 infection. They were diagnosed to have high-altitude resident pulmonary edema. They completely recovered following 4-7 days of treatment with oxygen inhalation, vasodilation, diuretics, and glucocorticoids.


Assuntos
COVID-19 , Edema Pulmonar , Humanos , Criança , Altitude , Edema Pulmonar/etiologia , Edema Pulmonar/diagnóstico , COVID-19/complicações , SARS-CoV-2
17.
PLoS One ; 18(9): e0291717, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37708155

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0181014.].

18.
Commun Biol ; 6(1): 1268, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097699

RESUMO

Recent developments in single-cell technology have enabled the exploration of cellular heterogeneity at an unprecedented level, providing invaluable insights into various fields, including medicine and disease research. Cell type annotation is an essential step in its omics research. The mainstream approach is to utilize well-annotated single-cell data to supervised learning for cell type annotation of new singlecell data. However, existing methods lack good generalization and robustness in cell annotation tasks, partially due to difficulties in dealing with technical differences between datasets, as well as not considering the heterogeneous associations of genes in regulatory mechanism levels. Here, we propose the scPML model, which utilizes various gene signaling pathway data to partition the genetic features of cells, thus characterizing different interaction maps between cells. Extensive experiments demonstrate that scPML performs better in cell type annotation and detection of unknown cell types from different species, platforms, and tissues.


Assuntos
Medicina , Análise da Expressão Gênica de Célula Única , Transdução de Sinais , Tecnologia
19.
Diagnostics (Basel) ; 12(2)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35204544

RESUMO

Interferon-gamma release assays (IGRAs) are widely used in the diagnosis of Mycobacterium tuberculosis (M. tuberculosis) infection by detecting interferon-γ released by previously sensitized T-cells in-vitro. Currently, there are two assays based on either enzyme-linked immunosorbent assay (ELISA) or enzyme-linked immunospot (ELISPOT) technology, with several generations of products available. The diagnostic value of IGRAs in the immunocompromised population is significantly different from that in the immunocompetent population because their results are strongly affected by the host immune function. Both physiological and pathological factors can lead to an immunocompromised situation. We summarized the diagnostic value and clinical recommendations of IGRAs for different immunocompromised populations, including peoplewith physiological factors (pregnant and puerperal women, children, and older people), as well as people with pathological factors (solid organ transplantation recipients, combination with human immunodeficiency virus infection, diabetes mellitus, end-stage renal disease, end-stage liver disease, and chronic immune-mediated inflammatory diseases). Though the performance of IGRAs is not perfect and often requires a combination with other diagnostic strategies, it still has some value in the immunocompromised population. Hopefully, the newly developed IGRAs could better target this population.

20.
Front Psychol ; 13: 960049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35959048

RESUMO

Objectives: As the largest cohort of healthcare workers and nurses can practice as psychotherapists to integrate the psychotherapeutic interventions as part of routine care. The present study aims to evaluate the effectiveness of supportive psychotherapy (SPT) on patients who had been scheduled to undergo a fiberoptic bronchoscopy (FOB) procedure. Methods: This study retrospectively analyzed 92 patients who underwent FOB, which was divided into the SPT group and usual-care group based on whether patients were given SPT interventions or not. The Patient Health Questionnaire-9 (PHQ-9) and Hospital Anxiety and Depression Scale (HADS) were used to determine the severity of depression and anxiety, as well as the 36-Item Short-Form Health Survey questionnaire (SF-36) to evaluate the health-related quality of life (HRQoL). Moreover, the patients' satisfaction was assessed based on the Likert 5-Point Scale. Results: The baseline status of anxiety, depression, and HRQoL in patients was similar in the SPT group and the usual-care group with no significant difference. Both PHQ-9 score and HADS-D score in the SPT group after intervention were lower than that in the usual-care group, accompanied by the deceased HADS-A subscale. Moreover, the improved HRQoL was found in the patients undergoing FOB after SPT interventions as compared to those receiving conventional nursing care using the SF-36 score. Additionally, the patient satisfaction in the SPT group was higher than in the usual-care group. Conclusions: The study demonstrated that anxiety and depression, as negative emotions, can be reduced by supportive psychotherapy in patients receiving FOB with improved mental health and satisfaction with nursing care.

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