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1.
ISME Commun ; 4(1): ycae025, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38584646

RESUMO

Plasmids are so closely associated with pathogens and antibiotic resistance that their potential for conferring other traits is often overlooked. Few studies consider how the full suite of traits encoded by plasmids is related to a host's environmental adaptation, particularly for Gram-positive bacteria. To investigate the role that plasmid traits might play in microbial communities from natural ecosystems, we identified plasmids carried by isolates of Curtobacterium (phylum Actinomycetota) from a variety of soil environments. We found that plasmids were common, but not ubiquitous, in the genus and varied greatly in their size and genetic diversity. There was little evidence of phylogenetic conservation among Curtobacterium plasmids even for closely related bacterial strains within the same ecotype, indicating that horizontal transmission of plasmids is common. The plasmids carried a wide diversity of traits that were not a random subset of the host chromosome. Furthermore, the composition of these plasmid traits was associated with the environmental context of the host bacterium. Together, the results indicate that plasmids contribute substantially to the microdiversity of a soil bacterium and that this diversity may play a role in niche differentiation and a bacterium's adaptation to its local environment.

2.
mBio ; 14(1): e0319122, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36629415

RESUMO

Plasmids are key mobile genetic elements in bacterial evolution and ecology as they allow the rapid adaptation of bacteria under selective environmental changes. However, the genetic information associated with plasmids is usually considered separately from information about their environmental origin. To broadly understand what kinds of traits may become mobilized by plasmids in different environments, we analyzed the properties and accessory traits of 9,725 unique plasmid sequences from a publicly available database with known bacterial hosts and isolation sources. Although most plasmid research focuses on resistance traits, such genes made up <1% of the total genetic information carried by plasmids. Similar to traits encoded on the bacterial chromosome, plasmid accessory trait compositions (including general Clusters of Orthologous Genes [COG] functions, resistance genes, and carbon and nitrogen genes) varied across seven broadly defined environment types (human, animal, wastewater, plant, soil, marine, and freshwater). Despite their potential for horizontal gene transfer, plasmid traits strongly varied with their host's taxonomic assignment. However, the trait differences across environments of broad COG categories could not be entirely explained by plasmid host taxonomy, suggesting that environmental selection acts on the plasmid traits themselves. Finally, some plasmid traits and environments (e.g., resistance genes in human-related environments) were more often associated with mobilizable plasmids (those having at least one detected relaxase) than others. Overall, these findings underscore the high level of diversity of traits encoded by plasmids and provide a baseline to investigate the potential of plasmids to serve as reservoirs of adaptive traits for microbial communities. IMPORTANCE Plasmids are well known for their role in the transmission of antibiotic resistance-conferring genes. Beyond human and clinical settings, however, they disseminate many other types of genes, including those that contribute to microbially driven ecosystem processes. In this study, we identified the distribution of traits genetically encoded by plasmids isolated from seven broadly categorized environments. We find that plasmid trait content varied with both bacterial host taxonomy and environment and that, on average, half of the plasmids were potentially mobilizable. As anthropogenic activities impact ecosystems and the climate, investigating and identifying the mechanisms of how microbial communities can adapt will be imperative for predicting the impacts on ecosystem functioning.


Assuntos
Bactérias , Ecossistema , Humanos , Plasmídeos/genética , Bactérias/genética , Antibacterianos , Transferência Genética Horizontal
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 6939-6942, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31947435

RESUMO

Certain patterns of eating behaviour during meal have been identified as risk factors for long-term abnormal eating development in healthy individuals and, eventually, can affect the body weight. To detect early signs of problematic eating behaviour, this paper proposes a novel method for building behaviour assessment models. The goal of the models is to predict whether the in-meal eating behaviour resembles patterns associated with obesity, eating disorders, or low-risk behaviours. The models are trained using meals recorded with a plate scale from a reference population and labels annotated by a domain expert. In addition, the domain expert assigned scores that characterise the degree of any exhibited abnormal patterns. To improve model effectiveness, we use the domain expert's scores to create training error regularisation weights that alter the importance of each training instance for its class during model training. The behaviour assessment models are based on the SVM algorithm and the fuzzy SVM algorithm for their instance-weighted variation. Experiments conducted on meals recorded from 120 individuals show that: (a) the proposed approach can produce effective models for eating behaviour classification (for individuals), or for ranking (for populations); and (b) the instance-weighted fuzzy SVM models achieve significant performance improvements, compared to the non-weighted, standard SVM models.


Assuntos
Comportamento Alimentar , Refeições , Máquina de Vetores de Suporte , Algoritmos , Ingestão de Alimentos , Humanos , Obesidade
4.
Dig Dis Sci ; 40(1): 198-210, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7821111

RESUMO

Intestinal T-cell lines were generated from lamina propria mononuclear cells isolated from colonoscopic biopsies in ulcerative colitis patients and controls. In both ulcerative colitis and controls, expanded cells were constituted largely by T-cell receptor alpha beta+, CD4+, CD45RA- (helper), and CD8+, CD11b- (cytotoxic) phenotypes. T-cell receptor V beta gene usage was not significantly changed after cell expansion and no difference was observed between ulcerative colitis and controls. Ulcerative colitis cells, especially those derived from the patients with long-standing disease, showed significantly higher levels of cytotoxicity against the target cells, including those of colonic epithelial origin, and enhanced production of tumor necrosis factor-alpha and interferon-gamma after short incubation with anti-CD3 antibody. Generation of T-cell lines from colonoscopic biopsy specimens may be useful for detailed functional characterization of locally infiltrating T cells in ulcerative colitis patients.


Assuntos
Biópsia , Colite Ulcerativa/imunologia , Colonoscopia , Mucosa Intestinal/citologia , Subpopulações de Linfócitos T , Adolescente , Adulto , Southern Blotting , Linhagem Celular , Colite Ulcerativa/patologia , Citotoxicidade Imunológica , Feminino , Citometria de Fluxo , Humanos , Interferon gama/biossíntese , Mucosa Intestinal/imunologia , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
5.
Sangyo Igaku ; 35(1): 3-6, 1993 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-8445825

RESUMO

Biochemical examination and two-color flow cytometric analysis of lymphocyte subsets of the peripheral blood were carried out in 107 healthy males working in high noise environments. The level of hearing disorder was compared with these results. By audiometry at six frequency levels, 51 of the 107 healthy males showed hearing loss. Their mean value of hearing ability was 30 dB and/or above. Among the peripheral lymphocyte subsets, helper T cells of CD4+CD45R- were significantly increased and the CD4/CD8 ratio tended to be elevated. CD20 that indicate B cells were reduced. These results suggested a relationship between susceptibility to acoustic trauma and cell-mediated immunity.


Assuntos
Perda Auditiva Provocada por Ruído/imunologia , Subpopulações de Linfócitos/imunologia , Exposição Ocupacional , Adulto , Humanos , Masculino , Pessoa de Meia-Idade
6.
Am J Gastroenterol ; 87(4): 448-54, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1553932

RESUMO

Phenotypic and functional analysis was performed with lamina propria mononuclear cells (LPMCs) isolated from colonoscopic biopsies in 27 patients with ulcerative colitis (UC). The proportion of T lymphocytes displaying HLA-DR antigens, interleukin 2 (IL-2) receptor, and transferrin receptor was greater in active UC than in control diseases. When LPMCs were cultured with IL-2 or phytohemagglutinin for 72 h, there were no significant differences in the proportion of cells bearing these activation markers between active UC and controls. The proportion of CD56+ cells and lymphokine-activated killer (LAK) cell activity was lower in LPMCs from active UC than in control cells, and depletion of CD56+ cells from control lamina propria cells essentially eliminated LAK cell activity. Mucosal T lymphocytes may be activated in vivo during active inflammation in UC, and lower levels of intestinal LAK cell activity may be related to the decrease of CD56+ cells under these conditions.


Assuntos
Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Mucosa Intestinal/patologia , Leucócitos Mononucleares/fisiologia , Adolescente , Adulto , Idoso , Análise de Variância , Anticorpos Monoclonais , Biópsia , Separação Celular , Colonoscopia , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Mucosa Intestinal/imunologia , Células Matadoras Ativadas por Linfocina/fisiologia , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade
7.
Nihon Eiseigaku Zasshi ; 44(2): 607-14, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2810862

RESUMO

The effects of alcohol and cigarette consumption on serum concentrations of alpha-carotene and beta-carotene in 312 healthy male adults, aged from 20 to 58 years, were investigated. Serum concentrations of beta-carotene were lower in alcohol drinkers (17.8 micrograms/dl; 0.33 mumol/l) than in nondrinkers (23.2 micrograms/dl; 0.43 mumol/l). Serum concentrations of alpha- and beta-carotenes were higher in nonsmokers (alpha-carotene: 7.4 micrograms/dl; beta-carotene: 22.6 micrograms/dl) than in current smokers (alpha-carotene: 5.9 micrograms/dl; beta-carotene: 18.4 micrograms/dl). In simple correlation and multiple regression analyses, smoking, smoking and alcohol drinking were inversely correlated with serum concentrations of alpha- and beta-carotenes in healthy adults. In contrast, serum concentrations of alpha- and beta-carotenes rose significantly with an increasing intake frequency of green-yellow vegetables or fruits. In addition, the effect of alcohol drinking on the serum beta-carotene concentration was more pronounced that that of smoking.


Assuntos
Consumo de Bebidas Alcoólicas , Carotenoides/sangue , Fumar/sangue , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , beta Caroteno
8.
Arch Dermatol ; 124(10): 1511-3, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3421726

RESUMO

Random culturing of the scalp in 200 healthy children in a large metropolitan children's hospital revealed that eight (4%) of the patients had cultures that were positive for Trichophyton tonsurans variety sulfureum. Infections were not clinically apparent and were asymptomatic. All of the patients with positive cultures were black and six braided their hair. Trichophyton tonsurans appears to exist in an asymptomatic state in this well-defined population of children.


Assuntos
Portador Sadio/microbiologia , Couro Cabeludo/microbiologia , Tinha do Couro Cabeludo/microbiologia , Trichophyton/isolamento & purificação , População Urbana , População Negra , Portador Sadio/epidemiologia , Criança , Feminino , Humanos , Masculino , Missouri , Tinha do Couro Cabeludo/epidemiologia , População Branca
10.
Toxicol Lett ; 37(2): 105-14, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3037732

RESUMO

Results from a cross-sectional study showed the concentration of lead in the blood of male workers, aged 20-55 years, occupationally exposed to lead in a steel factory, to be negatively correlated with the daily nutritional content of dietary fiber, iron and vitamin B1 (thiamine) intake. Furthermore, in experiments with rats injected subcutaneously with lead acetate, lead levels in blood and femur of animals on a vitamin-rich laboratory chow were lower than those fed a general laboratory chow. Moreover, in the group fed the vitamin-rich chow, lead excretion in feces increased, while excretion in urine did not. These results suggest that lead excretion from the body may be increased by a high intake of nutrients such as thiamine, iron and fiber, that lead excretion in feces via bile may be enhanced by a large intake of vitamins such as thiamine and that accordingly the lead concentration in the blood of the workers is reduced.


Assuntos
Dieta , Chumbo/sangue , Vitaminas/farmacologia , Adulto , Animais , Peso Corporal/efeitos dos fármacos , Osso e Ossos/análise , Fibras na Dieta , Exposição Ambiental , Fezes/análise , Humanos , Injeções Subcutâneas , Chumbo/análise , Fígado/análise , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Endogâmicos
11.
Int Arch Occup Environ Health ; 56(2): 119-27, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-4055067

RESUMO

We studied whether lead exposure increased the serum lipid peroxide (LPO) level and inhibited blood superoxide dismutase (SOD) activity in workers with occupational exposure to lead and rats injected with lead. We examined the following subjects: (1) manual workers (712 males) from 18 to 59-years-old in steel production with occupational exposure to lead, (2) office workers (155 males) without exposure to lead, (3) rats subcutaneously injected with lead in concentrations of 10 or 20 mg/kg as lead acetate. The nutritional intakes of manual workers and office workers were approximately equal. Serum LPO and high-density lipoprotein cholesterol (HDL-CL) levels in manual workers (LPO: 4.4 +/- 1.9 nmol/ml, HDL-CL: 55.6 +/- 14.2 mg/dl) were significantly higher than those in office workers (LPO: 4.0 +/- 1.4 nmol/ml, HDL-CL: 53.0 +/- 13.9 mg/dl). Serum LPO level in the manual workers increased with an increase of the lead concentration in the blood, while blood SOD activity decreased. Similar phenomena were observed in rats subcutaneously injected with lead acetate. Furthermore, the addition of lead at higher than 20-microM concentrations to non-treated rats liver microsomes increased NADPH-dependent liquid peroxidation, and these lead concentrations inhibited bovine erythrocyte SOD activity in vitro assay system. In conclusion, the present results seem to indicate that the increase of serum LPO level in workers with occupational exposure to lead is due not only to the stimulation of lipid peroxidation, but also to the inhibition of SOD activity by exposure to lead in the manufacturing processes.


Assuntos
Chumbo/efeitos adversos , Peróxidos Lipídicos/sangue , Superóxido Dismutase/sangue , Adolescente , Adulto , Animais , HDL-Colesterol/sangue , Humanos , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Pessoa de Meia-Idade , Ocupações , Ratos , Ratos Endogâmicos
13.
Sangyo Igaku ; 25(5): 343-55, 1983 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-6668722

RESUMO

Relationships between serum lipid values and the quantity and quality of nutrient intakes of the employees in a steel factory were studied, and the following results were obtained. High density lipoprotein cholesterol (HDL-CL) and alpha-CL separated by electrophoresis in office workers were significantly lower than those of field workers and they were especially lower in cases of hypertriglyceridemia. HDL-CL, alpha-CL and Apo A values of workers with abnormal circulatory findings were demonstrated to drop down with increased cigarette smoking or carbohydrate intake. On the other hand, these values were apt to be elevated with increased alcohol or energy intake. beta-Lipoprotein and beta-CL separated by electrophoresis in workers with hyperlipidemia or abnormal electrocardiogram findings were shown to be at significantly high levels. Furthermore, beta-CL values in workers with abnormal circulatory findings were especially inclined to be elevated with increased cigarette smoking or fat intake.


Assuntos
Lipídeos/sangue , Fenômenos Fisiológicos da Nutrição , Medicina do Trabalho , Adulto , Consumo de Bebidas Alcoólicas , Apolipoproteínas/sangue , Colesterol/sangue , HDL-Colesterol , Humanos , Japão , Lipoproteínas HDL/sangue , Masculino , Metalurgia , Pessoa de Meia-Idade , Fumar
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