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1.
Pharmaceuticals (Basel) ; 16(10)2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37895884

RESUMO

Nanotechnology is one of the most advance and multidisciplinary fields. Recent advances in nanoscience and nanotechnology radically changed the way we diagnose, treat, and prevent various diseases in all aspects of human life. The use of plants and their extracts is one of the most valuable methods towards rapid and single-step protocol preparation for various nanoparticles, keeping intact "the green principles" over the conventional ones and proving their dominance for medicinal importance. A facile and eco-friendly technique for synthesizing silver nanoparticles has been developed by using the latex of Euphorbia royleana as a bio-reductant for reducing Ag+ ions in an aqueous solution. Various characterization techniques were employed to validate the morphology, structure, and size of nanoparticles via UV-Vis spectroscopy, XRD, SEM, and EDS. FTIR spectroscopy validates different functional groups associated with biomolecules stabilizing/capping the silver nanoparticles, while SEM and XRD revealed spherical nanocrystals with FCC geometry. The results revealed that latex extract-mediated silver nanoparticles (LER-AgNPs) exhibited promising antibacterial activity against both gram-positive and -negative bacterial strains (Bacillus pumilus, Staphylococcus aureus, E. coli, Pseudomonas aeruginosa, and Streptococcus viridians). Both latex of E. royleana and LER-AgNPs were found to be potent in scavenging DPPH free radicals with respective EC50s and EC70s as 0.267% and 0.518% and 0.287% and 0.686%. ROSs produced in the body damage tissue and cause inflammation in oxidative stress-originated diseases. H2O2 and OH* scavenging activity increased with increasing concentrations (20-100 µg/mL) of LER-AgNPs. Significant reestablishment of ALT, AST, ALP, and bilirubin serum levels was observed in mice intoxicated with acetaminophen (PCM), revealing promising hepatoprotective efficacy of LER-AgNPs in a dose-dependent manner.

2.
Front Neurosci ; 13: 1184, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824239

RESUMO

This study was conducted to explore the composition of the fecal microflora of Chinese Parkinson's disease (PD) patients, as well as to explore links between PD clinical features and antiparkinsonian medications on the gut microflora. Seventy-two PD cases [59 patients suffering from PD for >1 year (OPD) and 13 new PD (NPD) patients] were studied. Microflora communities in the feces of the patients and corresponding healthy controls (HCs) were examined using high-throughput Illumina MiSeq sequencing targeting the 16S rRNA gene. The gut microflora of OPD patients contained high levels of Rikenellaceae compared to corresponding HCs. In addition, significantly higher levels of Turicibacteraceae were found in the NPD group compared to the corresponding HCs. The genera Turicibacter and Prevotella were significantly correlated with the PD severity scores. Our findings that some fecal microflora were closely related to PD clinical characteristics may enhance our understanding of the pathogenesis and treatment of PD.

3.
Microb Drug Resist ; 24(10): 1466-1474, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29902105

RESUMO

Acinetobacter baumannii is a nonfermenting Gram-negative bacillus. A. baumannii resistance is a significant obstacle to clinical infection treatment. The existence of persister cells (persisters) might represent the reason for therapy failure and relapse, and such cells may be the driving force behind rising resistance rates. In this study, A. baumannii ATCC 19606 was used as a target to explore the essential features of A. baumannii persisters. Antibiotic treatment of A. baumannii cultures at 50-fold the minimum inhibitory concentration resulted in a distinct plateau of surviving drug-tolerant persisters. The sensitive bacteria were lysed with ceftazidime, and the nonreplicating bacteria were isolated for transcriptome analysis using RNA sequencing. We analyzed the transcriptome of A. baumannii persisters and identified significantly differentially expressed genes, as well as their enriched pathways. The results showed that both the GP49 (HigB)/Cro (HigA) and DUF1044/RelB toxin/antitoxin systems were significantly increased during the persister incubation period. In addition, the activities of certain metabolic pathways (such as electron transport, adenosine triphosphate [ATP], and the citrate cycle) decreased sharply after antibiotic treatment and remained low during the persister period, while aromatic compound degradation genes were only upregulated in persisters. These results suggest the involvement of aromatic compound degradation genes in persister formation and maintenance. They further provide the first insight into the mechanism of persister formation in A. baumannii.


Assuntos
Acinetobacter baumannii/genética , Farmacorresistência Bacteriana/genética , Regulação Bacteriana da Expressão Gênica , Redes e Vias Metabólicas/genética , Transcriptoma , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/crescimento & desenvolvimento , Acinetobacter baumannii/metabolismo , Antibacterianos/farmacologia , Biotransformação , Ceftazidima/farmacologia , Ciclo do Ácido Cítrico/efeitos dos fármacos , Ciclo do Ácido Cítrico/genética , Análise por Conglomerados , Transporte de Elétrons/efeitos dos fármacos , Transporte de Elétrons/genética , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Hidrocarbonetos Aromáticos/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Sistemas Toxina-Antitoxina/efeitos dos fármacos , Sistemas Toxina-Antitoxina/genética
4.
Nutrients ; 10(2)2018 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-29425155

RESUMO

BACKGROUND: Elevated serum uric acid (SUA) involved in iron metabolism, has been increasingly recognized as a risk factor for gout and cardiovascular diseases. The objective of this study was to examine the associations between markers of iron status with risk of hyperuricemia (HU) in Chinese adult population. METHODS: Data were extracted from the 2009 wave of the China Health and Nutrition Survey, consisting of 7946 apparently healthy adults. Serum ferritin (SF), transferrin, soluble transferrin receptors (sTfR), hemoglobin (Hb), high-sensitivity C-reactive protein (hs-CRP), and SUA were measured. Diet was assessed with three consecutive 24 h recalls. Demographic characteristics, smoking status, alcohol consumption, and physical activities were investigated using a structured questionnaire. Multilevel mixed-effects models were constructed to estimate the associations of SF, transferrin, sTfR, and Hb with SUA and the risk of HU. RESULTS: The crude prevalence of HU was 16.1%. SF, transferrin, and Hb levels were positively associated with SUA and the risk of HU after adjustment for cluster effects and potential confounders (all p-trend < 0.05). Compared with participants in the lowest quartile of SF, those in the highest quartile had significantly higher SUA concentrations (ß = 0.899 mg/dL, 95% confidence interval (CI): 0.788, 1.010; p < 0.001) and higher risk of HU (odds ratio (OR) = 3.086, 95% CI: 2.450, 3.888; p < 0.001). Participants with the highest quartile of transferrin had significantly higher SUA concentrations (ß = 0.488 mg/dL, 95% CI: 0.389, 0.587; p < 0.001) and higher risk of HU (OR: 1.900; 95% CI: 1.579, 2.286; p < 0.001) when compared with those with the lowest quartile. In male participants, those in the highest quartile of Hb had significantly higher risk of HU when compared to the reference group (OR: 1.401, 95% CI: 1.104, 1.777; p < 0.01); however, this association was not found in female participants (OR: 1.093; 95% CI: 0.821, 1.455; p = 0.544). CONCLUSION: SF, transferrin, and Hb levels were positively associated with the risk of HU, and additional studies are needed to confirm the findings, as well as to elucidate their underlying mechanisms.


Assuntos
Anemia Ferropriva/sangue , Ferritinas/sangue , Hemoglobinas/análise , Hiperuricemia/sangue , Estado Nutricional , Transferrina/análise , Regulação para Cima , Adulto , Idoso , Anemia Ferropriva/etnologia , Anemia Ferropriva/fisiopatologia , Biomarcadores/sangue , China/epidemiologia , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Hiperuricemia/epidemiologia , Hiperuricemia/etnologia , Hiperuricemia/etiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Estado Nutricional/etnologia , Prevalência , Fatores de Risco , Fatores Sexuais , Solubilidade , Ácido Úrico/sangue
5.
Protein Cell ; 8(2): 90-102, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27866330

RESUMO

Dementia is a comprehensive category of brain diseases that is great enough to affect a person's daily functioning. The most common type of dementia is Alzheimer's disease, which makes most of cases. New researches indicate that gastrointestinal tract microbiota are directly linked to dementia pathogenesis through triggering metabolic diseases and low-grade inflammation progress. A novel strategy is proposed for the management of these disorders and as an adjuvant for psychiatric treatment of dementia and other related diseases through modulation of the microbiota (e.g. with the use of probiotics).


Assuntos
Doença de Alzheimer , Microbioma Gastrointestinal , Doença de Alzheimer/metabolismo , Doença de Alzheimer/microbiologia , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/terapia , Humanos
6.
Acta Vet Hung ; 64(1): 1-12, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26919137

RESUMO

Trueperella (T.) pyogenes is an opportunistic pathogen that causes suppurative diseases in domestic animals. In this work, the properties, pathogenesis and phenotypic diversity of T. pyogenes isolates from bovine mastitis were studied. Both pyolysin (plo) and collagen-binding protein (cbp) virulence factor genes were detected by PCR in all T. pyogenes isolates (n = 50). Using the tissue culture plate method, 90% of T. pyogenes isolates were able to form biofilms. The minimum inhibitory concentrations (MICs) of 13 antimicrobials against T. pyogenes isolates were determined. High susceptibility was observed to rifampin (96%), ampicillin (94%), ciprofloxacin (94%), and penicillin (92%), while low susceptibility was found to trimethoprim-sulphamethoxazole (10%) and bacitracin (2%). The intracellular assay revealed that T. pyogenes isolates had different cytopathogenic effects on cells. The high percentage (28.6%) of T. pyogenes isolates suggests that this bacterium is an important contributor to mastitis. Moreover, the high occurrence of multidrug resistance, biofilm production, intracellular survival, and the temporal dynamics of T. pyogenes interactions are key factors for a better understanding of how immunity acts on infections with these bacteria and how they evade immune surveillance, thus highlighting the need for the prudent use of antimicrobial agents in veterinary medicine.


Assuntos
Infecções por Actinomycetales/microbiologia , Antibacterianos/uso terapêutico , Arcanobacterium/efeitos dos fármacos , Farmacorresistência Bacteriana , Mastite Bovina/microbiologia , Infecções por Actinomycetales/veterinária , Animais , Bovinos , China , Contagem de Colônia Microbiana , Feminino , Testes de Sensibilidade Microbiana , Fatores de Virulência
7.
Toxins (Basel) ; 6(12): 3552-67, 2014 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-25533519

RESUMO

Staphylococcal enterotoxins (SEs) are powerful superantigenic toxins produced by Staphylococcus aureus (S. aureus). They can cause food poisoning and toxic shock. However, their impact on bovine mammary epithelial cells (bMECs) is still unknown. In this study, the distribution of SE genes was evaluated in 116 S. aureus isolates from bovine mastitis, and the most prevalent genes were seh (36.2%), followed by sei (12.1%), seg (11.2%), ser (4.3%), sec (3.4%), sea (2.6%) and sed (1.7%). To better understand the effect of staphylococcal enterotoxin H (SEH) on bMECs, the seh gene was cloned and inserted into the prokaryotic expression vector, pET28a, and transformed into Escherichia coli BL21 (DE3). The recombinant staphylococcal enterotoxin H (rSEH) was expressed and purified as soluble protein. Bioactivity analysis showed that rSEH possessed the activity of stimulating lymphocytes proliferation. The XTT assay showed that 100 µg/mL of rSEH produced the cytotoxic effect on bMECs, and fluorescence microscopy and flow cytometry analysis revealed that a certain dose of rSEH is effective at inducing bMECs apoptosis in vitro. This indicates that SEs can directly lead to cellular apoptosis of bMECs in bovine mastitis associated with S. aureus.


Assuntos
Apoptose/efeitos dos fármacos , Enterotoxinas/toxicidade , Células Epiteliais/efeitos dos fármacos , Animais , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Clonagem Molecular , DNA Bacteriano/genética , Enterotoxinas/genética , Células Epiteliais/citologia , Análise de Sequência de DNA
8.
J Clin Microbiol ; 51(10): 3228-36, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23863572

RESUMO

Ornithobacterium rhinotracheale is a Gram-negative bacterium associated with respiratory diseases in many avian species, with worldwide distribution, and it causes significant economic loss to the poultry industry. In this study, the isolation and characterization of O. rhinotracheale small-colony variants (SCVs) are described for the first time. O. rhinotracheale isolates (n = 27) were recovered from tracheal samples (n = 321) collected from different avian species with clinical signs of respiratory disease. Of the 27 O. rhinotracheale isolates, 21 (77.8%) showed SCVs in their primary cultures. Five O. rhinotracheale SCV isolates showed high levels of stability and were chosen for further characterization with their wild-type (WT) isolates. Stable O. rhinotracheale SCVs were oxidase negative, while their WT isolates were positive. Growth curves for stable O. rhinotracheale SCVs indicated lower growth rates and longer lag phases than for their WT isolates. Furthermore, it was possible to increase the efficacy of the broth medium in supporting the growth of O. rhinotracheale WT isolates by supplementing it with 5% fetal bovine serum (FBS) and 2% IsoVitaleX Enrichment. Antibiotic susceptibility tests showed that O. rhinotracheale SCVs had higher MIC values than their WT isolates. This study suggests that successful antibiotic treatment of respiratory diseases associated with O. rhinotracheale must take into consideration the resistance patterns of O. rhinotracheale SCVs. Intracellular persistence in murine RAW 264.7 macrophages revealed that O. rhinotracheale SCV28 had higher survival rates than its WT isolate. Finally, small-colony variants may be important contributors to the pathogenesis of O. rhinotracheale.


Assuntos
Ornithobacterium/crescimento & desenvolvimento , Ornithobacterium/isolamento & purificação , Animais , Antibacterianos/farmacologia , Doenças das Aves/microbiologia , Aves , Linhagem Celular , Meios de Cultura/química , Infecções por Flavobacteriaceae/microbiologia , Infecções por Flavobacteriaceae/veterinária , Macrófagos/microbiologia , Camundongos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Dados de Sequência Molecular , Ornithobacterium/enzimologia , Ornithobacterium/genética , Oxirredutases/metabolismo , Infecções Respiratórias/microbiologia , Infecções Respiratórias/veterinária , Análise de Sequência de DNA , Traqueia/microbiologia
9.
Microb Drug Resist ; 19(2): 138-45, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23140248

RESUMO

Staphylococcus aureus is a major pathogen associated to bovine mastitis and has the ability to form a slow-growing population termed the small colony variants (SCVs). From 20 samples of 5 chronic S. aureus cases, 1 SCV isolate (SCV102) was recovered simultaneously with 1 of 8 S. aureus isolates. SCV102 showed auxotrophy for thymidine and had a slow growth rate. Intracellular persistence in human mammary epithelial cells (HBL100cell line) monolayer revealed that SCV102 isolate had minimal cytopathological effects compared with its parent strains. SCV102 isolate and its parent strain S. aureus 101 indicate similar resistant pattern to four antibiotics. On the contrary, the minimal inhibitory concentrations values for chloramphenicol and sulfadimethoxine were much higher in SCV102 than that of S. aureus 101. To the best of our knowledge this is the first time the isolation of S. aureus SCV102 from a persistent bovine mastitis has been reported in Beijing (China). This study suggests that SCV102 isolate may be an important contributor to persistent bovine mastitis.


Assuntos
Antibacterianos/farmacologia , Mastite Bovina/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Antibacterianos/uso terapêutico , Bovinos , China , Cloranfenicol/farmacologia , Cloranfenicol/uso terapêutico , Doença Crônica , Contagem de Colônia Microbiana/veterinária , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/microbiologia , Feminino , Humanos , Mastite Bovina/tratamento farmacológico , Testes de Sensibilidade Microbiana/veterinária , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Sulfadimetoxina/farmacologia , Sulfadimetoxina/uso terapêutico , Timidina/metabolismo
10.
Biochem Biophys Res Commun ; 410(4): 910-5, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21708129

RESUMO

Chronic excessive fluoride intake is known to be toxic and can lead to fluorosis and bone pathologies. However, the cellular mechanisms underlying NaF-induced cytotoxicity in osteoblasts are not well understood. The objectives of this study were to determine the effects of fluoride treatment on MC3T3-E1 osteoblastic cell viability, cell cycle analysis, apoptosis and the expression levels of bcl-2 family members: bcl-2 and bax. MC3T3-E1 cells were treated with 10(-5); 5 × 10(-5); 10(-4); 5 × 10(-4) and 10(-3)M NaF for up to 48 h. NaF was found to reduce cell viability in a temporal and concentration dependent manner and promote apoptosis even at low concentrations (10(-5)M). This increased apoptosis was due to alterations in the expression of both pro-apoptotic bax and anti-apoptotic bcl-2. The net result was a decrease in the bcl-2/bax ratio which was found at both the mRNA and protein levels. Furthermore, we also noted that NaF-induced S-phase arrest during the cell cycle of MC3T3-E1 cells. These data suggest that fluoride-induced osteoblast apoptosis is mediated by direct effects of fluoride on the expression of bcl-2 family members.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Fluoreto de Sódio/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia
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