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1.
J Med Virol ; 96(3): e29556, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38511554

RESUMO

Neutrophil extracellular traps (NETs) play a role in innate pathogen defense and also trigger B-cell response by providing antigens. NETs have been linked to vaccine-induced thrombotic thrombocytopenia. We postulated a potential link between NET biomarkers, NET-promoting autoantibodies, and adverse events (AEs) after COVID-19 vaccine boosters. Healthy donors (HDs) who received ChAdOx1-S (A), mRNA-1273 (M), or recombinant protein (MVC-COV1901) vaccines at the National Taiwan University Hospital between 2021 and 2022 were recruited. We measured serial NET-associated biomarkers, citrullinated-histone3 (citH3), and myeloperoxidase (MPO)-DNA. Serum citH3 and MPO-DNA were significantly or numerically higher in HDs who reported AEs (n = 100, booster Day 0/Day 30, p = 0.01/p = 0.03 and p = 0.30/p = 0.35, respectively). We also observed a positive correlation between rash occurrence in online diaries and elevated citH3. A linear mixed model also revealed significantly higher citH3 levels in mRNA-1273/ChAdOx1-S recipients than MVC-COV1901 recipients. Significant positive correlations were observed between the ratios of anti-heparin platelet factor 4 and citH3 levels on Booster Day 0 and naïve and between the ratios of anti-NET IgM and citH3 on Booster Day 30/Day 0 in the AA-M and MM-M group, respectively. The increased levels of citH3/MPO-DNA accompanied by NET-promoting autoantibodies suggest a potential connection between mRNA-1273/ChAdOx1-S vaccines and cardiovascular complications. These findings provide insights for risk assessments of future vaccines.


Assuntos
COVID-19 , Armadilhas Extracelulares , Humanos , Armadilhas Extracelulares/metabolismo , Vacinas contra COVID-19/efeitos adversos , Autoanticorpos , Vacina de mRNA-1273 contra 2019-nCoV , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , COVID-19/prevenção & controle , COVID-19/metabolismo , Biomarcadores , ChAdOx1 nCoV-19 , Vacinação , DNA/metabolismo , Adenoviridae
2.
PLoS Pathog ; 17(2): e1009289, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33577624

RESUMO

Bacterial extracellular DNA (eDNA) and activated platelets have been found to contribute to biofilm formation by Streptococcus mutans on injured heart valves to induce infective endocarditis (IE), yet the bacterial component directly responsible for biofilm formation or platelet adhesion remains unclear. Using in vivo survival assays coupled with microarray analysis, the present study identified a LiaR-regulated PspC domain-containing protein (PCP) in S. mutans that mediates bacterial biofilm formation in vivo. Reverse transcriptase- and chromatin immunoprecipitation-polymerase chain reaction assays confirmed the regulation of pcp by LiaR, while PCP is well-preserved among streptococcal pathogens. Deficiency of pcp reduced in vitro and in vivo biofilm formation and released the eDNA inside bacteria floe along with reduced bacterial platelet adhesion capacity in a fibrinogen-dependent manner. Therefore, LiaR-regulated PCP alone could determine release of bacterial eDNA and binding to platelets, thus contributing to biofilm formation in S. mutans-induced IE.


Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , DNA Bacteriano/metabolismo , Endocardite/microbiologia , Adesividade Plaquetária , Infecções Estreptocócicas/microbiologia , Streptococcus mutans/crescimento & desenvolvimento , Animais , Proteínas de Bactérias/genética , Endocardite/metabolismo , Endocardite/patologia , Espaço Extracelular/metabolismo , Voluntários Saudáveis , Interações Hospedeiro-Patógeno , Humanos , Ratos , Infecções Estreptocócicas/metabolismo , Infecções Estreptocócicas/patologia , Streptococcus mutans/genética
3.
Med Mycol ; 59(4): 379-391, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32712662

RESUMO

NDT80-like family genes are highly conserved across a large group of fungi, but the functions of each Ndt80 protein are diverse and have evolved differently among yeasts and pathogens. The unique NDT80 gene in budding yeast is required for sexual reproduction, whereas three NDT80-like genes, namely, NDT80, REP1, and RON1, found in Candida albicans exhibit distinct functions. Notably, it was suggested that REP1, rather than RON1, is required for N-acetylglucosamine (GlcNAc) catabolism. Although Candida tropicalis, a widely dispersed fungal pathogen in tropical and subtropical areas, is closely related to Candida albicans, its phenotypic, pathogenic and environmental adaptation characteristics are remarkably divergent. In this study, we focused on the Ron1 transcription factor in C. tropicalis. Protein alignment showed that C. tropicalis Ron1 (CtRon1) shares 39.7% identity with C. albicans Ron1 (CaRon1). Compared to the wild-type strain, the C. tropicalis ron1Δ strains exhibited normal growth in different carbon sources and had similar expression levels of several GlcNAc catabolic genes during GlcNAc treatment. In contrast, C. tropicalis REP1 is responsible for GlcNAc catabolism and is involved in GlcNAc catabolic gene expressions, similar to C. albicans Rep1. However, REP1 deletion strains in C. tropicalis promote hyphal development in GlcNAc with low glucose content. Interestingly, CtRON1, but not CaRON1, deletion mutants exhibited significantly impaired hyphal growth and biofilm formation. As expected, CtRON1 was required for full virulence. Together, the results of this study showed divergent functions of CtRon1 compared to CaRon1; CtRon1 plays a key role in yeast-hyphal dimorphism, biofilm formation and virulence. LAY ABSTRACT: In this study, we identified the role of RON1, an NDT80-like gene, in Candida tropicalis. Unlike the gene in Candida albicans, our studies showed that RON1 is a key regulator of hyphal formation, biofilm development and virulence but is dispensable for N-acetylglucosamine catabolism in C. tropicalis.


Assuntos
Acetilglucosamina/metabolismo , Biofilmes/crescimento & desenvolvimento , Candida tropicalis/crescimento & desenvolvimento , Candida tropicalis/genética , Hifas/crescimento & desenvolvimento , Receptores Proteína Tirosina Quinases/genética , Candida tropicalis/patogenicidade , Candida tropicalis/fisiologia , Regulação Fúngica da Expressão Gênica , Virulência/genética
4.
Nanotechnology ; 32(3): 035203, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33022668

RESUMO

The characteristics of conductive-bridging random access memory (CBRAM) with amorphous indium-tungsten-zinc-oxide (a-InWZnO) switching layer and copper (Cu) ion-supply layer were prepared by sputtering. It was found that the doping ratio of tungsten has a significant effect on the memory characteristics of the CBRAM, and the doping of tungsten acts as a suppressor of oxygen vacancies in the InWZnO film. The O 1s binding energy associated with the oxygen-deficient regions in the α-InWZnO thin film decreases with increasing tungsten doping ratio, which can be demonstrated by x-ray photoelectron spectroscopy. When the tungsten doping ratio is 15%, the a-InWZnO CBRAM can achieve the excellent memory characteristics, such as high switching endurance (up to 9.7 × 103 cycling endurance), low operating voltage, and good retention capability. Moreover, the electrical uniformity and switching behavior of InWZnO device are evidently improved as the doping ratio of tungsten in the switching layer increases. These results suggest that CBRAM based on novel material InWZnO have great potential to be used in high-performance memory devices.

5.
Brain Behav Immun ; 90: 26-46, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32739365

RESUMO

Evidence suggests that the Parkinson's disease (PD) pathogenesis is strongly associated with bidirectional pathways in the microbiota-gut-brain axis (MGBA), and psychobiotics may inhibit PD progression. We previously reported that the novel psychobiotic strain, Lactobacillus plantarum PS128 (PS128), ameliorated abnormal behaviors and modulated neurotransmissions in dopaminergic pathways in rodent models. Here, we report that orally administering PS128 for 4 weeks significantly alleviated the motor deficits, elevation in corticosterone, nigrostriatal dopaminergic neuronal death, and striatal dopamine reduction in 1-methyl-4-phenyl-1,2,3,6-tetrathydropyridine (MPTP)-induced PD mouse models. PS128 ingestion suppressed glial cell hyperactivation and increased norepinephrine and neurotrophic factors in the striatum of the PD-model mice. PS128 administration also attenuated MPTP-induced oxidative stress and neuroinflammation in the nigrostriatal pathway. Fecal analysis showed that PS128 modulated the gut microbiota. L. plantarum abundance was significantly increased along with methionine biosynthesis-related microbial modules. PS128 also suppressed the increased family Enterobacteriaceae and lipopolysaccharide and peptidoglycan biosynthesis-related microbial modules caused by MPTP. In conclude, PS128 ingestion alleviated MPTP-induced motor deficits and neurotoxicity.PS128 supplementation inhibited neurodegenerative processes in PD-model mice and may help prevent PD.


Assuntos
Lactobacillus plantarum , Fármacos Neuroprotetores , Doença de Parkinson , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Doença de Parkinson/tratamento farmacológico , Pirrolidinas
6.
Infect Immun ; 85(9)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28674029

RESUMO

Host factors, such as platelets, have been shown to enhance biofilm formation by oral commensal streptococci, inducing infective endocarditis (IE), but how bacterial components contribute to biofilm formation in vivo is still not clear. We demonstrated previously that an isogenic mutant strain of Streptococcus mutans deficient in autolysin AtlA (ΔatlA) showed a reduced ability to cause vegetation in a rat model of bacterial endocarditis. However, the role of AtlA in bacterial biofilm formation is unclear. In this study, confocal laser scanning microscopy analysis showed that extracellular DNA (eDNA) was embedded in S. mutans GS5 floes during biofilm formation on damaged heart valves, but an ΔatlA strain could not form bacterial aggregates. Semiquantification of eDNA by PCR with bacterial 16S rRNA primers demonstrated that the ΔatlA mutant strain produced dramatically less eDNA than the wild type. Similar results were observed with in vitro biofilm models. The addition of polyanethol sulfonate, a chemical lysis inhibitor, revealed that eDNA release mediated by bacterial cell lysis is required for biofilm initiation and maturation in the wild-type strain. Supplementation of cultures with calcium ions reduced wild-type growth but increased eDNA release and biofilm mass. The effect of calcium ions on biofilm formation was abolished in ΔatlA cultures and by the addition of polyanethol sulfonate. The VicK sensor, but not CiaH, was found to be required for the induction of eDNA release or the stimulation of biofilm formation by calcium ions. These data suggest that calcium ion-regulated AtlA maturation mediates the release of eDNA by S. mutans, which contributes to biofilm formation in infective endocarditis.


Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , DNA Bacteriano/metabolismo , Endocardite/microbiologia , Endocardite/patologia , N-Acetil-Muramil-L-Alanina Amidase/metabolismo , Streptococcus mutans/fisiologia , Animais , Proteínas de Bactérias/genética , DNA Ribossômico/análise , Modelos Animais de Doenças , Deleção de Genes , Valvas Cardíacas/microbiologia , Valvas Cardíacas/patologia , Microscopia Confocal , N-Acetil-Muramil-L-Alanina Amidase/genética , RNA Ribossômico 16S/genética , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Streptococcus mutans/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
7.
J Surg Res ; 220: 112-118, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29180171

RESUMO

BACKGROUND: Surgical management of Graves' disease (GD) is changing from subtotal to total thyroidectomy because the latter eliminates the risk of recurrence. However, to preserve thyroid function in a euthyroid state, subtotal thyroidectomy is still performed for GD in non-Western countries. Therefore, we designed a study to investigate the long-term outcomes in GD patients after subtotal thyroidectomy and the correlation between remnant weight and postoperative thyroid function. MATERIALS AND METHODS: This was a retrospective cohort observation study. Between January 2005 and December 2011, 415 consecutive GD patients treated by subtotal thyroidectomy were enrolled. All data were collected from 385 patients who underwent bilateral subtotal thyroidectomy and 57 patients who underwent the Hartley-Dunhill operation. The median postoperative follow-up time was 72 months (range 12-144 months). RESULTS: The mean weight of the preserved thyroid remnant was 5.1 g. Persistent or recurrent hyperthyroidism was observed in 119 (28.7%) patients. The median time of recurrence was 36 months (range 12-120 months). Hypothyroidism developed in over 50% of patients. A euthyroid state was achieved in only 19.3% of patients, and the rate did not increase significantly as remnant weight increased. Based on a Cox regression analysis, the remnant weight is an independent risk factor for persistent or recurrent hyperthyroidism (hazard ratio: 1.323, 95% confidence interval: 1.198-1.461, P < 0.001). CONCLUSIONS: Subtotal thyroidectomy with the intent to maintain a euthyroid state is not an optimal surgical strategy for the definitive treatment of GD because the persistence or recurrence rate is high and the euthyroid rate is lower than expected.


Assuntos
Doença de Graves/cirurgia , Hipotireoidismo/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Glândula Tireoide/fisiologia , Tireoidectomia/efeitos adversos , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Hipotireoidismo/etiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Recidiva , Estudos Retrospectivos , Fatores de Risco , Tireoidectomia/métodos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
8.
Exp Gerontol ; 195: 112529, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39079652

RESUMO

The rising global aging population underscores the urgency of maintaining the health and well-being of the elderly while reducing the healthcare burden. Anti-aging probiotics have emerged as a promising strategy. This study identified a novel anti-senescence probiotic, Lacticaseibacillus paracasei PS117 (PS117). The effects of PS117 and heat-treated PS117 (HT-PS117) supplementation on cognitive function of naturally-aged male mice were investigated. It was found that PS117 supplementation improved the cognitive performance of aged mice in the Y-maze test. Furthermore, the level of senescence-related protein p16INK4a (p16) were reduced, while anti-senescence protein sirtuin 1 (Sirt1) were increased in the hippocampus. In addition, there was an overall improvement in the intestinal function. Distinct changes in the gut microbiota were also identified, suggesting a potential contribution to the beneficial effects of PS117 supplementation. In conclusion, these results suggest that PS117 supplements could improve cognitive and intestinal functions in naturally-aged mice, while HT-117 improves only intestinal function, possibly by improving the gut microbiota composition.


Assuntos
Envelhecimento , Cognição , Microbioma Gastrointestinal , Lacticaseibacillus paracasei , Probióticos , Animais , Probióticos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Cognição/efeitos dos fármacos , Envelhecimento/fisiologia , Camundongos , Lacticaseibacillus paracasei/fisiologia , Hipocampo/efeitos dos fármacos , Sirtuína 1/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Camundongos Endogâmicos C57BL , Aprendizagem em Labirinto/efeitos dos fármacos , Suplementos Nutricionais
9.
Med Mycol ; 51(5): 473-82, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23210679

RESUMO

Candida spp. are part of the natural human microbiota, but they also represent important opportunistic human pathogens. Biofilm-associated Candida albicans infections are clinically relevant due to their high levels of resistance to traditional antifungal agents. In this study, we investigated the ability of linalool to inhibit the formation of C. albicans biofilms and reduce existing C. albicans biofilms. Linalool exhibited antifungal activity against C. albicans ATCC 14053, with a minimum inhibitory concentration (MIC) of 8 mM. Sub-MIC concentrations of linalool also inhibited the formation of germ tubes and biofilms in that strain. The defective architecture composition of C. albicans biofilms exposed to linalool was characterized by scanning electron microscopy. The expression levels of the adhesin genes HWP1 and ALS3 were downregulated by linalool, as assessed by real-time RT-PCR. The expression levels of CYR1 and CPH1, which encode components of the cAMP-PKA and MAPK hyphal formation regulatory pathways, respectively, were also suppressed by linalool, as was the gene encoding their upstream regulator, Ras1. The expression levels of long-term hyphae maintenance associated genes, including UME6, HGC1, and EED1, were all suppressed by linalool. These results indicate that linalool may have therapeutic potential in the treatment of candidiasis associated with medical devices because it interferes with the morphological switch and biofilm formation of C. albicans.


Assuntos
Antifúngicos/farmacologia , Biofilmes/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Monoterpenos/farmacologia , Monoterpenos Acíclicos , Candida albicans/citologia , Candida albicans/crescimento & desenvolvimento , Moléculas de Adesão Celular/biossíntese , Moléculas de Adesão Celular/genética , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura
10.
Probiotics Antimicrob Proteins ; 15(2): 312-325, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-34449056

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by midbrain dopaminergic neuronal loss and subsequent physical impairments. Levodopa manages symptoms best, while deep brain stimulation (DBS) is effective for advanced PD patients; however, side effects occur with the diminishing therapeutic window. Recently, Lactiplantibacillus plantarum PS128 (PS128) was found to elevate dopamine levels in rodent brains, suggesting its potential to prevent PD. Here, the therapeutic efficacy of PS128 was examined in the 6-hydroxydopamine rat PD model. Suppression of the power spectral density of beta oscillations (beta PSD) in the primary motor cortex (M1) was recorded as the indicator of disease progression. We found that 6 weeks of daily PS128 supplementation suppressed M1 beta PSD as well as did levodopa and DBS. Long-term normalization of M1 beta PSD was found in PS128-fed rats, whereas levodopa and DBS showed only temporal effects. PS128 + levodopa and PS128 + DBS exhibited better therapeutic effects than did levodopa + DBS or either alone. Significantly improved motor functions in PS128-fed rats were correlated with normalization of M1 beta PSD. Brain tissue analyses further demonstrated the role of PS128 in dopaminergic neuroprotection and the enhanced availability of neurotransmitters. These findings suggest that psychobiotic PS128 might be used alongside conventional therapies to treat PD patients.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Ratos , Animais , Doença de Parkinson/tratamento farmacológico , Levodopa/efeitos adversos , Oxidopamina/efeitos adversos , Núcleo Subtalâmico/fisiologia , Dopamina/uso terapêutico
11.
Front Endocrinol (Lausanne) ; 14: 1063837, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817581

RESUMO

Background: Secondary hyperparathyroidism (SHPT) is a common condition in patients with end-stage renal disease (ESRD) who are on dialysis. Parathyroidectomy is a treatment for patients when medical therapy has failed. Recurrence may occur and is indicated for further surgery in the era of improved quality of care for ESRD patients. Methods: We identified, 1060 patients undergoing parathyroidectomy from January, 2011 to June, 2020. After excluding patients without regular check-up at our institute, primary hyperparathyroidism, or malignancy, 504 patients were enrolled. Sixty-two patients (12.3%, 62/504) were then excluded due to persistent SHPT even after the first parathyroidectomy. We aimed to identify risk factors for recurrent SHPT after the first surgery. Results: During the study period, 20% of patients who underwent parathyroidectomy at our institute (in, 2019) was due to recurrence after a previous parathyroidectomy. There were 442 patients eligible for analysis of recurrence after excluding patients with the persistent disease (n = 62). While 44 patients (9.95%) had recurrence, 398 patients did not. Significant risk factors for recurrent SHPT within 5 years after the first parathyroidectomy, including dialysis start time to first operation time < 3 years (p = 0.046), postoperative PTH >106.5 pg/mL (p < 0.001), and postoperative phosphorus> 5.9 mg/dL (p = 0.016), were identified by multivariate analysis. Conclusions: The starting time of dialysis to first operation time < 3 years in the patients with dialysis, postoperative PTH> 106.5 pg/mL, and postoperative phosphorus> 5.9 mg/dL tended to have a higher risk for recurrent SHPT within 5 years after primary treatment.


Assuntos
Hiperparatireoidismo Secundário , Falência Renal Crônica , Humanos , Hormônio Paratireóideo , Recidiva , Hiperparatireoidismo Secundário/complicações , Hiperparatireoidismo Secundário/cirurgia , Paratireoidectomia/efeitos adversos , Fósforo
12.
Microorganisms ; 10(10)2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36296316

RESUMO

Supplementation with specific probiotics has been shown to improve allergic airway symptoms. This study aimed to investigate immunomodulatory effects of a potential probiotic strain isolated from breast milk, Lactobacillus paragasseri BBM171 (BBM171), in an ovalbumin (OVA)-induced allergic mouse model. OVA-sensitized and OVA-challenged BALB/c mice were orally administered live or heat-inactivated BBM171 for 48 consecutive days. After the last allergen challenge, serum immunoglobulin (Ig) levels, inflammatory cell levels in the lungs, and cytokine levels in bronchoalveolar lavage fluid (BALF) were assessed. The results showed that oral administration of live or heat-inactivated BBM171 decreased serum levels of total IgE, OVA-specific IgE, and OVA-specific IgG1, while increasing OVA-specific IgG2a and reducing the extent of airway inflammation in OVA-induced allergic mice. In addition, both live and heat-inactivated BBM171 modulated the cytokine profile in BALF to a type 1 T helper (Th1) response. Furthermore, ex vivo experiments using OVA-induced allergic mouse splenocytes showed that both live and heat-inactivated BBM171 could regulate the Th1/Th2 balance, decrease the proinflammatory cytokine interleukin (IL)-17 level, and increase the anti-inflammatory cytokine IL-10 level. Taken together, these results suggest that oral administration of live or heat-inactivated BBM171 improved allergen-induced airway inflammation symptoms by modulating the host immune response toward Th1 dominance.

13.
Thromb Haemost ; 122(7): 1198-1208, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34768303

RESUMO

Formation of intravenous catheter-related thrombosis leads to central venous stenosis in patients requiring renal replacement therapy or chemotherapy infusion, yet the triggers or mechanisms remain unclear, especially in patients without symptoms of infection. In this study, we found that neutrophil extracellular traps (NETs) could be detected in the fibrin sheaths from dialysis patients without clinical manifestations of infection. Confocal microscopy revealed bacteria imbedded in NETs in the fibrin sheaths. Thirty-nine of 50 (78%) fibrin sheath specimens contained bacteria detectable by 16S ribosomal RNA genome typing with a predominance of Staphylococcus aureus (69%). In rat models, transient bacteremia of S. aureus induced NETs in enlarged fibrin sheaths, and treatment with DNase I alone significantly reduced both NET and fibrin sheath formation surrounding the catheter. Therefore, transient bacteremia could be a silent trigger that induces NET-related immunothrombosis enhancing catheter-related central venous stenosis.


Assuntos
Bacteriemia , Armadilhas Extracelulares , Trombose , Trombose Venosa , Animais , Bacteriemia/diagnóstico , Cateteres de Demora/efeitos adversos , Cateteres de Demora/microbiologia , Constrição Patológica , Fibrina , Neutrófilos , Ratos , Staphylococcus aureus , Trombose/etiologia , Trombose Venosa/etiologia
14.
Virulence ; 13(1): 1379-1392, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35876630

RESUMO

The role of secretion chaperone-regulated virulence proteins in the pathogenesis of infective endocarditis (IE) induced by viridans streptococci such as Streptococcus mutans is unclear. In this study, we investigated the contribution of the foldase protein PrsA, a putative parvulin-type peptidyl-prolyl isomerase, to the pathogenesis of S. mutans-induced IE. We found that a prsA-deficient strain had reduced virulence in terms of formation of vegetation on damaged heart valves, as well as reduced autolysis activity, eDNA release and biofilm formation capacity. The secretion and surface exposure of AtlA in vitro was reduced in the prsA-deficient mutant strain, and complementation of recombinant AtlA in the culture medium restored a wild type biofilm phenotype of the prsA-deficient mutant strain. This result suggests that secretion and surface localization of AtlA is regulated by PrsA during biofilm formation. Together, these results demonstrate that S. mutans PrsA could regulate AtlA-mediated eDNA release to contribute to biofilm formation in the pathogenesis of IE.


Assuntos
Endocardite Bacteriana , Endocardite , Proteínas de Bactérias/metabolismo , Biofilmes , DNA/metabolismo , Humanos , Streptococcus mutans/genética
15.
Food Funct ; 13(17): 8907-8919, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35924970

RESUMO

Nurses often experience adverse health effects associated with increasing levels of work-related stress. Stress may induce systemic effects through the HPA axis, glucocorticoid responses, and inflammatory cascades. Psychobiotics may help alleviate stress through associations of the microbiota, anti-inflammation factors, and the gut-brain axis. We aimed to investigate whether interventions with a psychobiotic, heat-killed (HK)-PS23 cells, may help improve perceived stress, anxiety, and related biological markers among highly stressed clinical nurses. This double-blind, randomized, placebo-controlled study included seventy clinical nurses from a medical center in Northern Taiwan who scored 27 or higher on the 10-item version of the Perceived Stress Scale (PSS), and participants were randomized into either taking HK-PS23 or a placebo for 8 weeks. Baseline and endpoint results of the PSS, Job Stress Scale, State and Trait Anxiety Index (STAI), emotional questionnaires, gastrointestinal severity questionnaires, Trails Marking Tests, blood biological markers, and sleep data were analyzed. While both groups demonstrated improvements in most measures over time, only the blood cortisol measure demonstrated significant group differences after the 8-week trial. Further analyses of the subgroup with higher anxiety (nurses with STAI ≥ 103) revealed that anxiety states had improved significantly in the HK-PS23 group but not in the placebo group. In summary, this placebo-controlled trial found significant reduction in the level of blood cortisol after 8 weeks of HK-PS23 use. The distinctive anxiolytic effects of HK-PS23 may be beneficial in improving perceived anxiety and stress hormone levels in female nurses under pressure. Clinical trial registration: https://clinicaltrials.gov/, identifier: NCT04452253-sub-project 1.


Assuntos
Hidrocortisona , Sistema Hipotálamo-Hipofisário , Ansiedade/tratamento farmacológico , Suplementos Nutricionais/análise , Método Duplo-Cego , Feminino , Temperatura Alta , Humanos , Sistema Hipófise-Suprarrenal
16.
J Microbiol Immunol Infect ; 55(5): 860-869, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35577736

RESUMO

BACKGROUND: Neutrophil extracellular traps (NETs) play important roles in sepsis and deep-seated infections, but whether NET formation correlates with clinical outcomes of patients with streptococcal bloodstream infections (BSIs) is unclear. METHODS: We analyzed serum levels of complexes of myeloperoxidase and DNA (MPO-DNA) in patients with streptococcal-BSIs. In vitro assay of NET induction by serum from BSI patients was performed. RESULTS: MPO-DNA values for the Streptococci-BSI group (n = 59) were significantly higher than those for healthy controls (p < 0.00001) and matched control groups (n = 59, p = 0.004). The rate of higher MPO-DNA levels (>1.87 µg/mL) were higher in abscess-prone streptococcal groups (streptococcus milleri group) (72.2% vs. 52.5%, p = 0.02). For patients with BSIs due to highly infective endocarditis (IE)-prone pathogens, the values of serum MPO-DNA were also higher in patients diagnosed of IE compared to their counterparts (p = 0.009). Notably, serum from patients with leukopenia could induce higher amounts of in vitro NET formation, despite having low MPO-DNA levels, suggesting that NET formation could be influenced by WBC counts. Therefore, we combined WBC counts with MPO-DNA to predict all-cause 30-day mortality in patients with commensal streptococcal-BSIs. The mortality risk was lowest among patients who had neither high MPO-DNA levels nor abnormal WBC counts (p = 0.058). Furthermore, this group of patients also had a favorable composite outcome consisting of major adverse cardiovascular events (MACE) and all-cause mortality (p = 0.026). CONCLUSION: Together, these study data suggested that serum MPO-DNA can be a biomarker for predicting a composite outcome consisting of MACE and all-cause mortality in patients with commensal streptococcal-BSIs.


Assuntos
Bacteriemia , Doenças Cardiovasculares , Armadilhas Extracelulares , Sepse , Humanos , Peroxidase , Biomarcadores , DNA , Neutrófilos
17.
BMC Evol Biol ; 11: 83, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21450111

RESUMO

BACKGROUND: The study of speciation in the marine realm is challenging because of the apparent absence of physical barriers to dispersal, which are one of the main drivers of genetic diversity. Although phylogeographic studies using mitochondrial DNA (mtDNA) information often reveal significant genetic heterogeneity within marine species, the evolutionary significance of such diversity is difficult to interpret with these markers. In the northwestern (NW) Pacific, several studies have emphasised the potential importance of sea-level regression during the most recent glaciations as a driver of genetic diversity in marine species. These studies have failed, however, to determine whether the period of isolation was long enough for divergence to attain speciation. Among these marine species, the cosmopolitan estuarine-dependent fish Mugil cephalus represents an interesting case study. Several divergent allopatric mtDNA lineages have been described in this species worldwide, and three occur in sympatry in the NW Pacific. RESULTS: Ten nuclear microsatellites were surveyed to estimate the level of genetic isolation of these lineages and determine the role of sea-level fluctuation in the evolution of NW Pacific M. cephalus. Three cryptic species of M. cephalus were identified within this region (NWP1, 2 and 3) using an assignment test on the microsatellite data. Each species corresponds with one of the three mtDNA lineages in the COI phylogenetic tree. NWP3 is the most divergent species, with a distribution range that suggests tropical affinities, while NWP1, with a northward distribution from Taiwan to Russia, is a temperate species. NWP2 is distributed along the warm Kuroshio Current. The divergence of NWP1 from NWP2 dates back to the Pleistocene epoch and probably corresponds to the separation of the Japan and China Seas when sea levels dropped. Despite their subsequent range expansion since this period of glaciation, no gene flow was observed among these three lineages, indicating that speciation has been achieved. CONCLUSIONS: This study successfully identified three cryptic species in M. cephalus inhabiting the NW Pacific, using a combination of microsatellites and mitochondrial genetic markers. The current genetic architecture of the M. cephalus species complex in the NW Pacific is the result of a complex interaction of contemporary processes and historical events. Sea level and temperature fluctuations during Plio-Pleistocene epochs probably played a major role in creating the marine species diversity of the NW Pacific that is found today.


Assuntos
Ecossistema , Especiação Genética , Água do Mar/química , Smegmamorpha/genética , Animais , DNA Mitocondrial/genética , Proteínas de Peixes/genética , Fluxo Gênico , Variação Genética , Biologia Marinha , Repetições de Microssatélites , Dados de Sequência Molecular , Noroeste dos Estados Unidos , Oceanos e Mares , Filogenia , Smegmamorpha/classificação , Temperatura
18.
Nanomaterials (Basel) ; 11(9)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34578520

RESUMO

In this study, the influence of oxygen concentration in InWZnO (IWZO), which was used as the switching layer of conductive bridge random access memory, (CBRAM) is investigated. With different oxygen flow during the sputtering process, the IWZO film can be fabricated with different oxygen concentrations and different oxygen vacancy distribution. In addition, the electrical characteristics of CBRAM device with different oxygen concentration are compared and further analyzed with an atomic force microscope and X-ray photoelectron spectrum. Furthermore, a stacking structure with different bilayer switching is also systematically discussed. Compared with an interchange stacking layer and other single layer memory, the CBRAM with specific stacking sequence of bilayer oxygen-poor/-rich IWZO (IWZOx/IWZOy, x < y) exhibits more stable distribution of a resistance state and also better endurance (more than 3 × 104 cycles). Meanwhile, the memory window of IWZOx/IWZOy can even be maintained over 104 s at 85 °C. Those improvements can be attributed to the oxygen vacancy distribution in switching layers, which may create a suitable environment for the conductive filament formation or rupture. Therefore, it is believed that the specific stacking bilayer IWZO CBRAM might further pave the way for emerging memory applications.

19.
BMC Complement Med Ther ; 21(1): 259, 2021 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627204

RESUMO

BACKGROUND: According to recent evidence, psychobiotics exert beneficial effects on central nervous system-related diseases, such as mental disorders. Lactobacillus plantarum PS128 (PS128), a novel psychobiotic strain, improves motor function, depression, and anxiety behaviors. However, the psychobiotic effects and mechanisms of PS128 in Alzheimer's disease (AD) remain to be explored. OBJECTIVES: The goal of the current study was to evaluate the beneficial effects of PS128 and to further elucidate its mechanism in AD mice. METHODS: PS128 (1010 colony-forming unit (CFU)/ml) was administered via oral gavage (o.g.) to 6-month-old male wild-type B6 and 3 × Tg-AD mice (harboring the PS1M146V, APPswe and TauP30IL transgenes) that received an intracerebroventricular injection of streptozotocin (icv-STZ, 3 mg/kg) or vehicle (saline) for 33 days. After serial behavioral tests, fecal short-chain fatty acid levels and AD-related pathology were assessed in these mice. RESULTS: Our findings show that intracerebroventricular injection of streptozotocin accelerated cognitive dysfunction associated with increasing levels of glycogen synthase kinase 3 beta (GSK3ß) activity, tau protein phosphorylation at the T231 site (pT231), amyloid-ß (Aß) deposition, amyloid-ß protein precursor (AßPP), ß-site AßPP-cleaving enzyme (BACE1), gliosis, fecal propionic acid (PPA) levels and cognition-related neuronal loss and decreasing postsynaptic density protein 95 (PSD95) levels in 3 × Tg-AD mice. PS128 supplementation effectively prevented the damage induced by intracerebroventricular injection of streptozotocin in 3 × Tg-AD mice. CONCLUSIONS: Based on the experimental results, intracerebroventricular injection of streptozotocin accelerates the progression of AD in the 3 × Tg-AD mice, primarily by increasing the levels of gliosis, which were mediated by the propionic acid and glycogen synthase kinase 3 beta pathways. PS128 supplementation prevents damage induced by intracerebroventricular injection of streptozotocin by regulating the propionic acid levels, glycogen synthase kinase 3 beta activity, and gliosis in 3 × Tg-AD mice. Therefore, we suggest that PS128 supplementation is a potential strategy to prevent and/or delay the progression of AD.


Assuntos
Disfunção Cognitiva/prevenção & controle , Lactobacillus plantarum/metabolismo , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer , Animais , Modelos Animais de Doenças , Gliose/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Propionatos/metabolismo , Estreptozocina/administração & dosagem
20.
Sci Rep ; 11(1): 7318, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795739

RESUMO

Acinetobacter baumannii-induced nosocomial pneumonia has become a serious clinical problem because of high antibiotic resistance rates. Antimicrobial peptides (AMP) are an ideal alternative strategy due to their broad-spectrum of antimicrobial activity and low incidence of bacterial resistance. However, their application is limited by toxicity and stability in vivo. The present study used a mouse model to directly identify potential AMPs effective for treatment of A. baumannii-induced pneumonia. Fifty-eight AMPs were screened and two identified (SMAP-29 and TP4) to have prophylactic effects which prevented the death of mice with pneumonia. Furthermore, two TP4 derivatives (dN4 and dC4) were found to have therapeutic activity in pneumonia mouse models by peritoneal or intravenous administration. Both dN4 and dC4 also inhibited and/or eliminated A. baumannii biofilms at higher doses. Taken together, these data suggest the AMP derivatives dN4 and dC4 represent a potential treatment strategy for A. baumannii-induced pneumonia.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , Infecções por Acinetobacter/microbiologia , Animais , Biofilmes/efeitos dos fármacos , Carbapenêmicos/farmacologia , Química Farmacêutica/métodos , Modelos Animais de Doenças , Desenho de Fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Hemólise , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos , Proteínas Citotóxicas Formadoras de Poros , Células-Tronco
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