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1.
Infect Immun ; 91(2): e0057022, 2023 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-36692308

RESUMO

A disrupted "dysbiotic" gut microbiome engenders susceptibility to the diarrheal pathogen Clostridioides difficile by impacting the metabolic milieu of the gut. Diet, in particular the microbiota-accessible carbohydrates (MACs) found in dietary fiber, is one of the most powerful ways to affect the composition and metabolic output of the gut microbiome. As such, diet is a powerful tool for understanding the biology of C. difficile and for developing alternative approaches for coping with this pathogen. One prominent class of metabolites produced by the gut microbiome is short-chain fatty acids (SCFAs), the major metabolic end products of MAC metabolism. SCFAs are known to decrease the fitness of C. difficile in vitro, and high intestinal SCFA concentrations are associated with reduced fitness of C. difficile in animal models of C. difficile infection (CDI). Here, we use controlled dietary conditions (8 diets that differ only by MAC composition) to show that C. difficile fitness is most consistently impacted by butyrate, rather than the other two prominent SCFAs (acetate and propionate), during murine model CDI. We similarly show that butyrate concentrations are lower in fecal samples from humans with CDI than in those from healthy controls. Finally, we demonstrate that butyrate impacts growth in diverse C. difficile isolates. These findings provide a foundation for future work which will dissect how butyrate directly impacts C. difficile fitness and will lead to the development of diverse approaches distinct from antibiotics or fecal transplant, such as dietary interventions, for mitigating CDI in at-risk human populations. IMPORTANCE Clostridioides difficile is a leading cause of infectious diarrhea in humans, and it imposes a tremendous burden on the health care system. Current treatments for C. difficile infection (CDI) include antibiotics and fecal microbiota transplant, which contribute to recurrent CDIs and face major regulatory hurdles, respectively. Therefore, there is an ongoing need to develop new ways to cope with CDI. Notably, a disrupted "dysbiotic" gut microbiota is the primary risk factor for CDI, but we incompletely understand how a healthy microbiota resists CDI. Here, we show that a specific molecule produced by the gut microbiota, butyrate, is negatively associated with C. difficile burdens in humans and in a mouse model of CDI and that butyrate impedes the growth of diverse C. difficile strains in pure culture. These findings help to build a foundation for designing alternative, possibly diet-based, strategies for mitigating CDI in humans.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Humanos , Animais , Camundongos , Butiratos , Permissividade , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ácidos Graxos Voláteis
2.
Mass Spectrom Rev ; 40(3): 236-254, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32530096

RESUMO

Chlorinated dioxins are labeled and recognized by both the World Health Organization and the United Nations Environmental Programme (UNEP) as "persistent organic pollutants". Their potential for high toxicity is one of the primary factors behind intense public and regulatory scrutiny and the need to measure the compounds at very low limits, specifically the isomer 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). This article highlights the early mass spectrometry methods to investigate, detect, confirm, and quantify chlorinated dioxins and the initial applications involving human biomonitoring, as attempts were made to attribute health effects to TCDD exposure. This effort represented a complex and difficult scientific response to the pressing need to investigate expected exposures and alleged subsequent medical effects, which in the case of the Viet Nam veterans was being attempted a decade or more after their exposure. It is noteworthy that this method and its development touched on delicate issues involving human subjects, war veterans, environmental contamination, and was difficult not only scientifically, but for ethical and political reasons as well. Stable-isotope dilution with analysis by gas chromatography/high-resolution mass spectrometry (GC/HRMS) became the method of choice because of its ability to monitor characteristic ions and isotope ratios to quantify and qualify/confirm the analyte in the presence of coextracting and coeluting interferences at these low levels with the highest possible confidence. This method was rigorously tested and validated before it was used to discover and monitor levels in the environment and in various populations at then unprecedented low levels. These early studies demonstrated the feasibility of monitoring dioxins in humans even decades after exposure, and led to the detection of 2,3,7,8-TCDD in the general population as well as specific overexposed populations. These studies also provided strong evidence regarding the origins of the 2,3,7,8-isomer in the environment. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.


Assuntos
Dioxinas/análise , Dioxinas/toxicidade , Poluentes Ambientais/análise , Espectrometria de Massas/métodos , Animais , Dioxinas/farmacocinética , Poluentes Ambientais/farmacocinética , Poluentes Ambientais/toxicidade , Cromatografia Gasosa-Espectrometria de Massas/métodos , Meia-Vida , Humanos , Leite Humano/química , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/análise , Dibenzodioxinas Policloradas/análise , Primatas , Veteranos , Vietnã
3.
Clin Psychol Psychother ; 29(4): 1331-1341, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35023259

RESUMO

Metacognitive beliefs have emerged as important to health anxiety, particularly beliefs that health-related thoughts are uncontrollable. Preliminary research examining generalized worry indicates uncontrollability beliefs relate more strongly to anxiety among US-based self-identifying White relative to Black college students. The present study sought to extend that line of research by examining if metacognitive beliefs about the uncontrollability of health-related thoughts differentially relate to health anxiety among self-identifying non-Latinx Black (n = 123), Latinx (n = 104) and non-Latinx White (n = 80) US-based primary care patients. As predicted, although positive associations were seen across all three groups, beliefs that health-related thoughts are uncontrollable more strongly related to health anxiety among White patients compared to both Black and Latinx patients. Those differential relations held in multivariate analyses while statistically controlling for positive depression screening status, generalized anxiety symptom severity and medical morbidity. Although the effect size surrounding the differential relations was small in magnitude, the present results further support the notion that metacognitive beliefs about uncontrollability relate less strongly to anxiety among US-based ethnoracial minorities compared to White individuals. Potential reasons for the differential relations are discussed, along with additional areas for future research.


Assuntos
Ansiedade , Metacognição , Ansiedade/psicologia , Transtornos de Ansiedade/psicologia , Humanos , Atenção Primária à Saúde , Estudantes/psicologia
4.
Mol Cell Biochem ; 476(2): 1303-1312, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33301106

RESUMO

The sheared avian intestinal villus-crypts exhibit high tendency to self-repair and develop enteroids in culture. Presuming that this transition process involves differential biomolecular changes, we employed matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) to find whether there were differences in the spectral profiles of sheared villi versus the enteroids, assessed in the mass range of 2-18 kDa. The results showed substantial differences in the intensities of the spectral peaks, one particularly corresponding to the mass of 4963 Da, which was significantly low in the sheared villus-crypts compared with the enteroids. Based on our previous results with other avian tissues and further molecular characterization by LC-ESI-IT-TOF-MS, and multiple reaction monitoring (MRM), the peak was identified to be thymosin ß4 (Tß4), a ubiquitously occurring regulatory peptide implicated in wound healing process. The identity of the peptide was further confirmed by immunohistochemistry which showed it to be present in a very low levels in the sheared villi but replete in the enteroids. Since Tß4 sequesters G-actin preventing its polymerization to F-actin, we compared the changes in F-actin by its immunohistochemical localization that showed no significant differences between the sheared villi and enteroids. We propose that depletion of Tß4 likely precedes villous reparation process. The possible mechanism for the differences in Tß4 profile in relation to the healing of the villus-crypts to developing enteroids is discussed.


Assuntos
Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Mucosa Intestinal/citologia , Espectrometria de Massas/métodos , Proteoma/metabolismo , Timosina/metabolismo , Cicatrização , Animais , Técnicas de Cultura de Células/métodos , Galinhas , Mucosa Intestinal/metabolismo , Proteoma/análise
5.
Rapid Commun Mass Spectrom ; 35 Suppl 1: e8349, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30421829

RESUMO

RATIONALE: Assessing the utility of vacuum matrix-assisted ionization (MAI) for the direct and rapid analysis of lipids in complex samples with emphasis on bacterial taxonomy. METHODS: Matrix-assisted ionization Fourier transform mass spectrometry (MAI-FTMS) was used to characterize polar and non-polar lipids in mixtures. RESULTS: For non-polar lipid triacylglycerols (TAGs), MAI-FTMS produced lipid-specific ions for eight different edible oils and allowed these oils to be identified based on their MAI-FTMS profiles. For polar lipids from bacteria, MAI-FTMS of crude lipid extracts allowed taxonomic identification of eight blind-coded samples based on taxonomy-specific phospholipid profiles. MAI produced results comparable and complementary to benchmark MALDI and ESI methods currently used for characterization of polar and non-polar lipids in the same mixtures. CONCLUSIONS: The newly developed MAI technique is a rapid, simple and complementary method for the characterization of polar and non-polar lipids in complex mixtures.


Assuntos
Lipídeos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Bactérias/química , Análise de Fourier , Lipídeos/análise , Lipídeos/química
6.
Qual Life Res ; 29(12): 3297-3304, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32651803

RESUMO

PURPOSE: The purpose of this study was to measure the association between peripheral neuropathy symptoms and depressive symptoms among a sample of patients with and without diabetes mellitus (DM). METHODS: Patients were administered the 15-item Michigan Neuropathy Screening Instrument (MNSI) and the patient health questionnaire depression scale (PHQ-8). Patients with an MNSI score ≥ 4 were categorized as having PN and patients with a PHQ-8 score ≥ 10 were considered to have current depression. Log-binomial regression was used to analyze the relationship between PN and depressive symptoms. RESULTS: 406 patients were included in the final analysis. There were no statistically significant differences by diabetes status in PN symptoms (Diabetes = 61.8%; No diabetes = 55.4%; p = .20) or in depression status (Diabetes = 37.6%; No diabetes = 36.6%; p = .83). After adjustment for covariates, PN was associated with depression (aRR = 4.46; 95% CI 2.91,6.85) independent of diabetes status. CONCLUSIONS: PN symptoms may be common among aging persons even in the absence of DM. Past literature and our study demonstrate that PN and depression are closely associated. More work is needed to understand the etiology and potential utility of intervention for depression symptoms among patients with neuropathy.


Assuntos
Depressão/psicologia , Diabetes Mellitus Tipo 2/complicações , Doenças do Sistema Nervoso Periférico/psicologia , Atenção Primária à Saúde/normas , Qualidade de Vida/psicologia , Depressão/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso Periférico/complicações , Inquéritos e Questionários
7.
J Behav Med ; 42(2): 217-223, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30043146

RESUMO

Extant research provides equivocal conclusions if the combined presentation of health anxiety with severe somatic symptoms confers risk for greater future primary care usage. The present study further examined the combination of health anxiety and somatic symptoms as a predictor of healthcare usage in primary care. Using a prospective longitudinal design, a large sample (N = 530) of patients presenting for treatment at a community health center completed self-report measures assessing health anxiety and somatic symptom severity. A medical record review at the time of questionnaire administration and 1 year following that administration was completed to assess the frequency of medical visits during the preceding and subsequent year. As expected, the interactive effect between health anxiety and somatic symptom severity predicted greater subsequent year medical visits. Covariates included preceding year medical visits, sociodemographic variables, body mass index, smoking status, and depressive symptom severity. Simple effects indicated that health anxiety predicted greater subsequent year medical visits when coupled with relatively severe, but not mild, somatic symptoms. Assessing health anxiety and somatic symptom severity in primary care settings could be important for identifying individuals at risk for future frequent healthcare visits and who may benefit from intervention.


Assuntos
Ansiedade/psicologia , Aceitação pelo Paciente de Cuidados de Saúde , Atenção Primária à Saúde , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Autorrelato , Adulto Jovem
8.
Br J Cancer ; 119(4): 462-470, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30057405

RESUMO

BACKGROUND: New approaches to ovarian cancer are needed to improve survival. Wilms' tumour 1 (WT1) is a tumour-associated antigen expressed in many ovarian cancers. P53 is also often altered. The clinical significance of the combined expression of these two transcription factors has not been studied. METHODS: One hundred ninety-six ovarian tumours were classified histopathologically. Tumours were stained for WT1 and p53 immunohistochemically. Stains were analysed according to tumour type, grade and FIGO stage. Kaplan-Meier analyses on 96 invasive carcinomas determined whether categorical variables were related to survival. RESULTS: WT1 and p53 were related to ovarian tumour type, grade, FIGO stage and patient survival. Uniform nuclear p53 expression was associated with invasion and WT1 expression was associated with advanced grade, FIGO stage and poor survival. When WT1 and p53 were both in the age-adjusted Cox model, WT1 was significant while p53 was not. When we combined tumours expressing WT1 and p53, then adjusted for age and tumour subtype, the hazard ratio compared to tumours without WT1 and with normal p53 was 2.70; when adjusted for age and FIGO stage, the hazard ratio was 2.40. CONCLUSIONS: WT1, an antigen target, is a biomarker for poor prognosis, particularly when combined with altered p53.


Assuntos
Biomarcadores Tumorais/metabolismo , Núcleo Celular/metabolismo , Neoplasias Ovarianas/patologia , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima , Proteínas WT1/metabolismo , Fatores Etários , Idoso , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Ovarianas/metabolismo , Prognóstico , Estudos Retrospectivos
9.
J Behav Med ; 41(1): 43-51, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28710565

RESUMO

Prior research indicates the common presentation of somatic symptoms and obesity in primary care settings, as well as links between obesity and somatic symptoms. Anxiety sensitivity, discomfort intolerance, and health anxiety are three variables relevant to somatic symptoms. How those three variables relate to somatic symptom severity among individuals who are obese and the unique variance accounted for by each variable in somatic symptom severity remains unexamined. Among a large sample of primary care patients who are obese (N = 342), anxiety sensitivity, discomfort intolerance, and health anxiety collectively accounted for 35% of variance in somatic symptom severity beyond the effects of sociodemographic variables, body mass index, medical morbidity, and depression severity. Health anxiety accounted for the largest amount of unique variance in somatic symptom severity, potentially supporting the relevance of health anxiety to the presentation of increased somatic symptoms among patients who are obese.


Assuntos
Adaptação Psicológica , Transtornos de Ansiedade/psicologia , Ansiedade/psicologia , Comportamento de Doença , Obesidade/psicologia , Transtornos Somatoformes/psicologia , Adulto , Ansiedade/diagnóstico , Transtornos de Ansiedade/diagnóstico , Índice de Massa Corporal , Comorbidade , Correlação de Dados , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Exercício Físico/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico , Atenção Primária à Saúde , Autoimagem , Transtornos Somatoformes/diagnóstico
10.
Br J Cancer ; 114(4): 444-53, 2016 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-26882068

RESUMO

BACKGROUND: Melanoma is a disease that primarily arises in the skin but is a derivative of the neural crest. Eukaryotic translation initiation factor 4E (eIF4E) regulates translation of multiple malignancy-associated mRNAs and is overexpressed in many epithelial tumours. However, expression in human tumours derived from the neural crest is unknown. Here, we determined the association of eIF4E and phospho-eIF4E expression in melanocytic lesions with malignant conversion, metastatic potential and patient survival. METHODS: Archived formalin-fixed, paraffin-embedded surgical specimens from 114 patients with melanocytic lesions were stained immunohistochemically for eIF4E and phospho-eIF4E and evaluated semiquantitatively. The relationship between cytoplasmic and nuclear eIF4E and phospho-eIF4E protein expression, melanocytic lesion subtype and tumour progression was determined. Kaplan-Meier survival analyses and Cox proportional hazard regression were performed. RESULTS: Increased eIF4E and phospho-eIF4E expression was highly associated with malignancy (P<0.0001). High nuclear phospho-eIF4E was associated with synchronous or future metastasis (P=0.0059). Kaplan-Meier analyses demonstrated highly significant associations between high histoscores for cytoplasmic and nuclear phospho-eIF4E and reduced survival in all patients (P=0.0003 and 0.0009, respectively). CONCLUSIONS: Increased melanoma expression of eIF4E and phospho-eIF4E is associated with metastatic potential, reduced survival and increased risk of death.


Assuntos
Biomarcadores Tumorais/metabolismo , Fator de Iniciação 4E em Eucariotos/metabolismo , Melanoma/metabolismo , Serina/metabolismo , Adulto , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Melanoma/mortalidade , Melanoma/patologia , Fosforilação , Estudos Retrospectivos
11.
Environ Manage ; 58(6): 1074-1090, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27688254

RESUMO

Oxygen concentrations and oxygen utilization rates were monitored continuously for 23 months on marsh platforms and in small tidal creeks at two sites in coastal Georgia, USA, that receive urban stormwater runoff via an extensive network of drainage canals. These data were compared to nearby control sites that receive no significant surface runoff. Overall, rainfall and runoff per se were not associated with differences in the oxygen dynamics among the different locations. Because of the large tidal range and long tidal excursions in coastal Georgia, localized inputs of stormwater runoff are rapidly mixed with large volumes of ambient water. Oxygen concentrations in tidal creeks and on flooded marsh platforms were driven primarily by balances of respiration and photosynthesis in the surrounding regional network of marshes and open estuarine waters. Local respiration, while measurable, was of relatively minor importance in determining oxygen concentrations in tidal floodwaters. Water residence time on the marshes could explain differences in oxygen concentration between the runoff-influenced and control sites.


Assuntos
Monitoramento Ambiental/métodos , Estuários , Inundações , Oxigênio/análise , Movimentos da Água , Áreas Alagadas , Georgia
12.
Bioconjug Chem ; 25(12): 2112-5, 2014 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-25426820

RESUMO

Control of small molecule hapten epitope densities on antigenic carrier proteins is essential for development and testing of optimal conditions for vaccines. Yet, accurate determination of epitope density can be extremely difficult to accomplish, especially with the use of small haptens, large molecular weight carrier proteins, and limited amounts of protein. Here we report a simple radiometric method that uses (14)C-labeled cystine to measure hapten epitope densities during sulfhydryl conjugation of haptens to maleimide activated carrier proteins. The method was developed using a (+)-methamphetamine (METH)-like hapten with a sulfhydryl terminus, and two prototype maleimide activated carrier proteins, bovine serum albumin (BSA) and immunocyanin monomers of keyhole limpet hemocyanin. The method was validated by immunochemical analysis of the hapten-BSA conjugates, and least-squares linear regression analysis of epitope density values determined by the new radiometric method versus values determined by matrix-assisted laser desorption/ionization mass spectrometry. Results showed that radiometric epitope density values correlated extremely well with the mass spectrometrically derived values (r(2) = 0.98, y = 0.98x + 0.91). This convenient and simple method could be useful during several stages of vaccine development including the optimization and monitoring of conditions for hapten-protein conjugations, and choosing the most effective epitope densities for conjugate vaccines.


Assuntos
Epitopos/análise , Haptenos/análise , Haptenos/química , Radiometria/métodos , Cistina/química , Haptenos/imunologia , Hemocianinas/química , Hemocianinas/imunologia , Maleimidas/química , Metanfetamina/química , Metanfetamina/imunologia , Peso Molecular , Proteínas/química , Proteínas/imunologia , Reprodutibilidade dos Testes , Soroalbumina Bovina/química , Soroalbumina Bovina/imunologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Compostos de Sulfidrila/química , Vacinas Conjugadas/química
13.
Microb Cell Fact ; 13: 79, 2014 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-24893720

RESUMO

BACKGROUND: Green microalgae represent a renewable natural source of vitamin E. Its most bioactive form is the naturally occurring RRR-α-tocopherol which is biosynthesized in photosynthetic organisms as a single stereoisomer. It is noteworthy that the natural and synthetic α-tocopherols are different biomolecular entities. This article focuses on RRR-α-tocopherol production in Stichococcus bacillaris strain siva2011 biomass in a bioreactor culture with methyl jasmonate (MeJa) elicitor. Additionally, a nonlinear mathematical model was used to quantitatively scale-up and predict the biomass production in a 20 L balloon bioreactor with dual variables such as time and volume. RESULTS: Approximately 0.6 mg/g dry weight (DW) of RRR-α-tocopherol was enhanced in S. bacillaris strain siva2011 biomass with the MeJa 50 µL/L for 24 hrs elicitations when compared to the control. The R2 value from the nonlinear model was enhanced up to 95% when compared to the linear model which significantly improved the accuracy for estimating S. bacillaris strain siva2011 biomass production in a balloon bioreactor. CONCLUSIONS: S. bacillaris strain siva2011 is a new green microalga which biosynthesizes significant amounts of RRR-α-tocopherol. Systematically validated dual variable empirical data should provide key insights to multivariable or fourth order modeling for algal biomass scale-up. This bioprocess engineering should provide valuable information for industrial production of RRR-α-tocopherol from green cells.


Assuntos
Clorófitas/metabolismo , alfa-Tocoferol/metabolismo , Acetatos/metabolismo , Biomassa , Reatores Biológicos , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Estereoisomerismo , alfa-Tocoferol/química
14.
Poult Sci ; 93(6): 1495-502, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24879699

RESUMO

Avian bile is rich in matrix metalloproteinases (MMP), the enzymes that cleave extracellular matrix proteins such as collagens and proteoglycans. Changes in bile MMP expression have been correlated with hepatic and gall bladder pathologies, but the significance of their expression in normal, healthy bile is not understood. We hypothesized that the MMP in bile may aid the digestion of native collagens that are resistant to conventional gastric proteases. Hence, the objective of this study was to characterize the bile MMP and check its regulation in association with dietary factors. We used substrate zymography, azocoll protease assay, and gelatin affinity chromatography to identify and purify the MMP from chicken bile. Using zymography and SDS PAGE, 5 bands at 70, 64, 58, 50, and 42 kDa were detected. The bands corresponding to 64, 50, and 42 kDa were identified as MMP2 using trypsin in-gel digestion and matrix-assisted laser desorption time-of-flight mass spectrometry and peptide mass fingerprinting. Chickens fed diets containing gelatin supplements showed higher levels of MMP expression in the bile by both azocoll assay and zymography. We conclude that the bile MMP may be associated with the digestion of collagens and other extracellular matrix proteins in avian diets.


Assuntos
Ração Animal/análise , Bile/efeitos dos fármacos , Bile/metabolismo , Galinhas/metabolismo , Suplementos Nutricionais/análise , Metaloproteinases da Matriz/metabolismo , Animais , Compostos Azo/metabolismo , Cromatografia de Afinidade/veterinária , Cromatografia em Gel/veterinária , Colágeno/metabolismo , Dieta/veterinária , Eletroforese em Gel de Poliacrilamida/veterinária , Masculino , Espectrometria de Massas/veterinária , Metaloproteinases da Matriz/isolamento & purificação , Distribuição Aleatória
15.
Res Q Exerc Sport ; 95(1): 1-9, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36608287

RESUMO

Purpose: Efficacy of exercise to improve renal health and filtration remains understudied in adults with moderate-stages (stages G3a-b) of chronic kidney disease (CKD). Acute exercise may contribute clinically relevant information for exercise-related augmentation of renal health and filtration in CKD. Urine epidermal growth factor (uEGF) and cystatin C (CyC) are proposed to be more direct biomarkers of renal health and filtration. This study aimed to determine the influence of continuous moderate-intensity exercise (CMIE) and high-intensity interval exercise (HIIE) on traditional and novel biomarkers of renal health and filtration in moderate-stages of CKD. Methods: Twenty CKD participants completed 30 minutes of both CMIE and HIIE. Blood and urine samples were obtained pre, 1-hour, and 24-hours post-exercise. Traditional-serum creatinine (sCr) urine creatinine, novel-uEGF, uEGF ratio (uEGFr), and CyC. Estimates of glomerular filtration rate (eGFR)-modification of diet in renal disease (MDRD) and the CKD-Epidemiology (CKD-EPI)-responses were compared pre, 1 hr, and 24 hr post-exercise. Results: Relative to pre-exercise measures, uEGF remained unchanged in both exercise conditions. However, uEGFr was 5.4% greater 24-hours after HIIE (P = .05), while uEGFr remained unchanged with CMIE. sCr decreased 6 to 19% 1-hour post-exercise in both conditions (P = .009). On average renal filtration increased in eGFR-MDRD (7.2 ± 2.0 ml/min/1.73 m2) (P = .007) and eGFR-CKD-EPI (8.6 ± 2.3 ml/min/1.73 m2) 1-hour post-exercise (P = .009). Conclusion: By clinical estimates, renal filtration in CKD was not normalized but transiently improved regardless of exercise condition, with HIIE eliciting transient improvements in renal health.


Assuntos
Insuficiência Renal Crônica , Adulto , Humanos , Exercício Físico , Biomarcadores
16.
JACC Heart Fail ; 12(6): 1015-1025, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520461

RESUMO

BACKGROUND: Diagnosis of heart failure with preserved ejection fraction (HFpEF) in patients with atrial fibrillation (AF) represents a significant clinical challenge. Two diagnostic scoring tools have been developed to aid the noninvasive diagnosis of HFpEF: the HFA-PEFF (Heart Failure Association Pre-test assessment, Echocardiography and natriuretic peptide, Functional testing, Final etiology) and the H2FPEF scoring systems. OBJECTIVES: The purpose of this study was to evaluate the performance of these 2 scoring tools for the diagnosis of HFpEF against a gold standard of invasive evaluation in a cohort of patients with AF. METHODS: The authors recruited consecutive patients with symptomatic AF and preserved ejection fraction who were scheduled for an AF ablation procedure. Gold-standard invasive diagnosis of HFpEF was performed at the AF ablation procedure using mean left atrial pressure at rest and following infusion of 500 mL fluid. Each participant was scored according to the noninvasive HFA-PEFF and H2FPEF scoring systems. Sensitivity and specificity analyses were performed to assess the accuracy of these scoring systems in diagnosing HFpEF. RESULTS: In total, 120 participants were recruited. HFpEF was diagnosed invasively in 88 (73.3%) participants, whereas 32 (26.7%) had no HFpEF. Using the HFA-PEFF score, 38 (31.7%) participants had a high probability of HFpEF and 82 (68.3%) had low/intermediate probability of HFpEF. Using the H2FPEF tool, 72 (60%) participants had a high probability of HFpEF and 48 (40%) had intermediate probability. A high HFA-PEFF (≥5 points) score could diagnose HFpEF with a sensitivity of 40% and a specificity of 91%, and a high H2FPEF score (≥6 points) could diagnose HFpEF with a sensitivity of 69% and specificity of 66%. Overall diagnostic accuracy was similar using both tools (AUC: 0.663 vs 0.707, respectively; P = 0.636). CONCLUSIONS: Against a gold standard of invasively diagnosed HFpEF, the HFA-PEFF and H2FPEF scores demonstrate only moderate accuracy in patients with AF and should be utilized with caution in this cohort of patients. (Characterising Left Atrial Function and Compliance in Atrial Fibrillation; ACTRN12620000639921).


Assuntos
Fibrilação Atrial , Ecocardiografia , Insuficiência Cardíaca , Volume Sistólico , Humanos , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/fisiopatologia , Feminino , Masculino , Volume Sistólico/fisiologia , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Idoso , Pessoa de Meia-Idade , Ecocardiografia/métodos , Peptídeo Natriurético Encefálico/sangue , Sensibilidade e Especificidade , Reprodutibilidade dos Testes
17.
Mol Cell Biochem ; 372(1-2): 127-35, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22983815

RESUMO

The outcome of sepsis occurs due to influence of environmental and genetic factors besides genes variants whose expression support its outcome or not. Oxidative stress is associated to the pathogenicity of sepsis, occurring when there is a reactive species overproduction associated with inflammation. The aim of this study was to characterize the cellular redox status of human peripheral blood mononuclear cells (PBMCs) with either -9Ala (AA) or -9Val (VV) SOD2 genotypes and evaluate their response to oxidative stress induced by lipopolysaccharide (LPS). The PBMCs were isolated from the blood of 30 healthy human volunteers (15 volunteers for each allele) and the following assays were performed: antioxidant enzyme activities (superoxide dismutase; catalase; glutathione peroxidase), total radical-trapping antioxidant parameter, non-enzymatic antioxidant capacity (total antioxidant reactivity), and quantification of conjugated dienes (lipid peroxidation). At basal conditions (i.e., not stimulated by LPS), cells from 47C allele carriers showed higher activities of CAT and SOD, as well as higher TAR compared to 47T allele. However, when 47CC cells were challenged with LPS, we observed a higher shift toward a pro-oxidant state compared to 47TT cells. The CAT activity and lipid peroxidation were increased in cells with both alleles, but SOD activity increased significantly only in 47TT cells. These results demonstrate that SOD2 polymorphisms are associated with different cellular redox environments at both basal and LPS-stimulated states, and identification of this polymorphism may be important for a better understanding of pro-inflammatory conditions.


Assuntos
Leucócitos Mononucleares/enzimologia , Lipopolissacarídeos/farmacologia , Polimorfismo de Nucleotídeo Único , Superóxido Dismutase/genética , Adulto , Substituição de Aminoácidos , Catalase , Células Cultivadas , Feminino , Radicais Livres/metabolismo , Glutationa Peroxidase/metabolismo , Heterozigoto , Humanos , Líquido Intracelular/enzimologia , Leucócitos Mononucleares/imunologia , Peroxidação de Lipídeos , Masculino , Nitritos/metabolismo , Estresse Oxidativo , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
18.
J Ind Microbiol Biotechnol ; 40(1): 51-62, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23114992

RESUMO

Xylose oligomers are the intermediate products of xylan depolymerization into xylose monomers. An understanding of xylan depolymerization kinetics is important to improve the conversion of xylan into monomeric xylose and to minimize the formation of inhibitory products, thereby reducing ethanol production costs. The study of xylan depolymerization requires copious amount of xylose oligomers, which are expensive if acquired commercially. Our approach consisted of producing in-house oligomer material. To this end, birchwood xylan was used as the starting material and hydrolyzed in hot water at 200 °C for 60 min with a 4 % solids loading. The mixture of xylose oligomers was subsequently fractionated by a centrifugal partition chromatography (CPC) with a solvent system of butanol:methanol:water in a 5:1:4 volumetric ratio. Operating in an ascending mode, the butanol-rich upper phase (the mobile phase) eluted xylose oligomers from the water-rich stationary phase at a 4.89 mL/min flow rate for a total fractionation time of 300 min. The elution of xylose oligomers occurred between 110 and 280 min. The yields and purities of xylobiose (DP 2), xylotriose (DP 3), xylotetraose (DP 4), and xylopentaose (DP 5) were 21, 10, 14, and 15 mg/g xylan and 95, 90, 89, and 68 %, respectively. The purities of xylose oligomers from this solvent system were higher than those reported previously using tetrahydrofuran:dimethyl sulfoxide:water in a 6:1:3 volumetric ratio. Moreover, the butanol-based solvent system improved overall procedures by facilitating the evaporation of the solvents from the CPC fractions, rendering the purification process more efficient.


Assuntos
Cromatografia Líquida/métodos , Solventes/química , Xilose/isolamento & purificação , 1-Butanol/química , Butanóis/química , Centrifugação , Cromatografia Líquida de Alta Pressão , Metanol/química , Polímeros/química , Espectrometria de Massas por Ionização por Electrospray , Água/química , Xilanos/química , Xilose/análise , Xilose/química
19.
Autophagy ; 19(5): 1551-1561, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36286616

RESUMO

LC3-dependent EV loading and secretion (LDELS) is a secretory autophagy pathway in which the macroautophagy/autophagy machinery facilitates the packaging of cytosolic cargos, such as RNA-binding proteins, into extracellular vesicles (EVs) for secretion outside of the cell. Here, we identify TFRC (transferrin receptor), one of the first proteins found to be secreted via EVs, as a transmembrane cargo of the LDELS pathway. Similar to other LDELS targets, TFRC secretion via EVs genetically requires components of the MAP1LC3/LC3-conjugation machinery but is independent of other ATGs involved in classical autophagosome formation. Furthermore, the packaging and secretion of this transmembrane protein into EVs depends on multiple ESCRT pathway components and the small GTPase RAB27A. Based on these results, we propose that the LDELS pathway promotes TFRC incorporation into EVs and its secretion outside the cell.Abbreviations: ATG: autophagy related; ESCRT: endosomal sorting complexes required for transport; EV: extracellular vesicle; EVP: extracellular vesicle and particle; ILV: intralumenal vesicle; LDELS: LC3-dependent EV loading and secretion; LIR: LC3-interacting region; MVE: multivesicular endosome; RBP: RNA-binding protein; TMT: tandem mass tag; TFRC: transferrin receptor.


Assuntos
Autofagia , Vesículas Extracelulares , Vesículas Extracelulares/metabolismo , Endossomos/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Receptores da Transferrina/metabolismo
20.
Biomed Pharmacother ; 161: 114424, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36827712

RESUMO

Melanoma is one of the most aggressive forms of skin cancer and is characterized by high metastatic potential. Despite improvements in early diagnosis and treatment, the mortality rate among metastatic melanoma patients continues to represent a significant clinical challenge. Therefore, it is imperative that we search for new forms of treatment. Trametes versicolor is a mushroom commonly used in Chinese traditional medicine due to its numerous beneficial properties. In the present work, we demonstrate T. versicolor fruiting body and mycelium ethanol extracts exhibit potent cytotoxic activity towards A375 (IC50 = 663.3 and 114.5 µg/mL respectively) and SK-MEL-5 (IC50 = 358.4 and 88.6 µg/mL respectively) human melanoma cell lines. Further studies revealed that T. versicolor mycelium extract induced apoptotic cell death and poly (ADP-ribose) polymerase cleavage, upregulated the expression of autophagy-associated marker LC3-II, increased the presentation of major histocompatibility complex II and expression of programmed death-ligand receptor, and inhibited cell migration in SK-MEL-5 cells. Therefore, our present findings highlight the therapeutic potential of T. versicolor mycelium extract for the treatment of melanoma and merit further study.


Assuntos
Antineoplásicos , Polyporaceae , Humanos , Trametes , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Micélio
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