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1.
Appl Environ Microbiol ; 87(6)2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33419736

RESUMO

Ocean acidification (OA) threatens the growth and function of coral reef ecosystems. A key component to coral health is the microbiome, but little is known about the impact of OA on coral microbiomes. A submarine CO2 vent at Maug Island in the Northern Mariana Islands provides a natural pH gradient to investigate coral responses to long-term OA conditions. Three coral species (Pocillopora eydouxi, Porites lobata, and Porites rus) were sampled from three sites where the mean seawater pH is 8.04, 7.98, and 7.94. We characterized coral bacterial communities (using 16S rRNA gene sequencing) and determined pH of the extracellular calcifying fluid (ECF) (using skeletal boron isotopes) across the seawater pH gradient. Bacterial communities of both Porites species stabilized (decreases in community dispersion) with decreased seawater pH, coupled with large increases in the abundance of Endozoicomonas, an endosymbiont. P. lobata experienced a significant decrease in ECF pH near the vent, whereas P. rus experienced a trending decrease in ECF pH near the vent. In contrast, Pocillopora exhibited bacterial community destabilization (increases in community dispersion), with significant decreases in Endozoicomonas abundance, while its ECF pH remained unchanged across the pH gradient. Our study shows that OA has multiple consequences on Endozoicomonas abundance and suggests that Endozoicomonas abundance may be an indicator of coral response to OA. We reveal an interesting dichotomy between two facets of coral physiology (regulation of bacterial communities and regulation of calcification), highlighting the importance of multidisciplinary approaches to understanding coral health and function in a changing ocean.IMPORTANCE Ocean acidification (OA) is a consequence of anthropogenic CO2 emissions that is negatively impacting marine ecosystems such as coral reefs. OA affects many aspects of coral physiology, including growth (i.e., calcification) and disrupting associated bacterial communities. Coral-associated bacteria are important for host health, but it remains unclear how coral-associated bacterial communities will respond to future OA conditions. We document changes in coral-associated bacterial communities and changes to calcification physiology with long-term exposure to decreases in seawater pH that are environmentally relevant under midrange IPCC emission scenarios (0.1 pH units). We also find species-specific responses that may reflect different responses to long-term OA. In Pocillopora, calcification physiology was highly regulated despite changing seawater conditions. In Porites spp., changes in bacterial communities do not reflect a breakdown of coral-bacterial symbiosis. Insights into calcification and host-microbe interactions are critical to predicting the health and function of different coral taxa to future OA conditions.


Assuntos
Antozoários/microbiologia , Antozoários/fisiologia , Calcificação Fisiológica , Água do Mar/química , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Concentração de Íons de Hidrogênio , Oceanos e Mares
2.
J Fish Biol ; 88(2): 727-34, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26508660

RESUMO

Needlefishes (Beloniformes) were observed employing a range of stalking and attacking behaviours to attack schools of bait fishes ranging from the use of tactics common to predatory fishes to a novel behaviour: the use of leaping, aerial attacks. These aerial attacks are suggested to serve two purposes: to extend the attack range of the needlefishes and to reduce their prey's potential for evasion. Furthermore, a third purpose is hypothesized that the needlefishes are taking advantage of Snell's Window, an optical effect which may mask their approach to their prey.


Assuntos
Beloniformes/fisiologia , Fenômenos Ópticos , Comportamento Predatório , Animais , Natação
3.
Health Phys ; 102(2): 182-95, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22217591

RESUMO

Mathematical methods were developed to construct dose and time distributions and their associated risks and threshold values for lethal and non-lethal effects of acute radiation exposure to include mortality and incidence, prodromal vomiting, and agranulocytosis. A new distribution (T-model) was obtained to describe time parameters of acute radiation syndrome such as the latency period, time to onset of vomiting, and time to initiation of agranulocytosis. Based on the dose and time distributions, the parameter translation method was defined using an orthogonal regression, which allows one to solve for these distributions in the case of acute radiation exposure. The assessment of threshold doses was performed for some effects of acute radiation syndrome: for the latency period, ∼6-8 Gy absorbed dose and ∼0.7-0.9 h time to onset of vomiting; and for incidence (agranulocytosis), ∼2-3 Gy absorbed dose and ∼2-3 h time to onset of vomiting. The obtained new formula for assessment of radiation risk is applicable to the time parameters of acute radiation syndrome.


Assuntos
Síndrome Aguda da Radiação/etiologia , Doses de Radiação , Relação Dose-Resposta à Radiação , Humanos , Análise de Regressão , Fatores de Tempo
4.
Anal Bioanal Chem ; 402(1): 473-87, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22127575

RESUMO

A suite of three green tea-containing Standard Reference Materials (SRMs) has been issued by the National Institute of Standards and Technology (NIST): SRM 3254 Camellia sinensis (Green Tea) Leaves, SRM 3255 Camellia sinensis (Green Tea) Extract, and SRM 3256 Green Tea-Containing Solid Oral Dosage Form. The materials are characterized for catechins, xanthine alkaloids, theanine, and toxic elements. As many as five methods were used in assigning certified and reference values to the constituents, with measurements carried out at NIST and at collaborating laboratories. The materials are intended for use in the development and validation of new analytical methods, and for use as control materials as a component in the support of claims of metrological traceability.


Assuntos
Camellia sinensis/química , Análise de Alimentos/normas , Chá/química , Análise de Alimentos/métodos , Padrões de Referência
5.
Blood ; 97(8): 2366-73, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11290599

RESUMO

Human herpesvirus 8 (HHV-8) is a recently discovered gammaherpesvirus that is the etiologic agent of Kaposi sarcoma (KS). The natural history of primary HHV-8 infection, including clinical outcome and host immune responses that may be important in preventing disease related to HHV-8, has not been elucidated. The present study characterized the clinical, immunologic, and virologic parameters of primary HHV-8 infection in 5 cases detected during a 15-year longitudinal study of 108 human immunodeficiency virus type 1 seronegative men in the Multicenter AIDS Cohort Study. Primary HHV-8 infection was associated with mild, nonspecific signs and symptoms of diarrhea, fatigue, localized rash, and lymphadenopathy. There were no alterations in numbers of CD4(+) or CD8(+) T cells or CD8(+) T-cell interferon gamma (IFN-gamma) production to mitogen or nominal antigen. CD8(+) cytotoxic T-lymphocyte precursor (CTLp) and IFN-gamma reactivity were detected during primary HHV-8 infection, with broad specificity to 5 lytic cycle proteins of HHV-8 encoded by open reading frame 8 (ORF 8; glycoprotein B homolog of Epstein-Barr virus), ORF 22 (gH homolog), ORF 25 (major capsid protein homolog), ORF 26 (a minor capsid protein homolog), or ORF 57 (an early protein homolog), in association with increases in serum antibody titers and appearance of HHV-8 DNA in blood mononuclear cells. CD8(+) T-cell responses to HHV-8 decreased by 2 to 3 years after primary infection. This antiviral T-cell response may control initial HHV-8 infection and prevent development of disease.


Assuntos
Antígenos Virais/imunologia , Glicoproteínas , Infecções por Herpesviridae/imunologia , Herpesvirus Humano 8/imunologia , Proteínas Virais/imunologia , Adulto , Sequência de Aminoácidos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Capsídeo/imunologia , DNA Viral/sangue , Exantema/etiologia , Fadiga/etiologia , Soronegatividade para HIV , Infecções por Herpesviridae/epidemiologia , Homossexualidade , Humanos , Memória Imunológica , Imunofenotipagem , Incidência , Interferon gama/biossíntese , Ionomicina/farmacologia , Estudos Longitudinais , Doenças Linfáticas/etiologia , Ativação Linfocitária , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Mitógenos/farmacologia , Dados de Sequência Molecular , Fosfoproteínas/imunologia , Estudos Prospectivos , Subpopulações de Linfócitos T , Acetato de Tetradecanoilforbol/farmacologia , Proteínas do Envelope Viral/imunologia , Proteínas da Matriz Viral/imunologia , Viremia/imunologia , Viremia/virologia
6.
J Infect Dis ; 179(2): 329-36, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9878015

RESUMO

CD4 T cell responses were studied for >2 years in 27 zidovudine-experienced patients with advanced human immunodeficiency virus type 1 (HIV-1) infection who received triple combination drug therapy with indinavir, zidovudine and lamivudine or zidovudine plus lamivudine or zidovudine alone for 24-42 weeks before switching to the three-drug therapy. Subjects initially given the three drugs had viremia suppressed to undetectable levels and increases in T cell proliferative and cytokine responses to microbial antigens through 2 years of follow-up. Patients receiving the triple-drug therapy after either indinavir or zidovudine-lamivudine treatment had similar increases in T cell responses only if they also had suppression of virus load. CD4 T cell reactivity to HIV-1 antigens was not restored. Prolonged indinavir-zidovudine-lamivudine treatment has significant but incomplete enhancing effects on CD4 T cell reactivity, which could be important in host control of microbial and persistent HIV-1 infections.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Fármacos Anti-HIV/uso terapêutico , Antígenos de Bactérias/imunologia , Linfócitos T CD4-Positivos/imunologia , Antígenos HIV/imunologia , HIV-1 , Viremia/imunologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adulto , Linfócitos T CD4-Positivos/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Quimiocinas/biossíntese , Citocinas/biossíntese , Método Duplo-Cego , Feminino , HIV-1/efeitos dos fármacos , HIV-1/imunologia , Humanos , Indinavir/uso terapêutico , Lamivudina/uso terapêutico , Masculino , Mitógenos/imunologia , RNA Viral/metabolismo , Viremia/tratamento farmacológico , Zidovudina/uso terapêutico
7.
Mutat Res ; 431(2): 279-89, 1999 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-10635994

RESUMO

Epidemiological studies have demonstrated associations between maternal tobacco smoke exposure and consumption of alcohol during pregnancy and increased risk of pediatric malignancies, particularly infant leukemias. Molecular evidence also suggests that somatic mutational events occurring during fetal hematopoiesis in utero can contribute to this process. As part of an ongoing multi-endpoint biomarker study of 2000 mothers and newborns, the HPRT T-lymphocyte cloning assay was used to determine mutant frequencies (Mf) in umbilical cord blood samples from an initial group of 60 neonates born to a sociodemographically diverse cohort of mothers characterized with respect to age, ethnicity, socioeconomic status, and cigarette smoke and alcohol exposure. Non-zero Mf (N = 47) ranged from 0.19 to 5.62 x 10(-6), median 0.70 x 10(-6), mean +/- SD 0.98 +/- 0.95 x 10(-6). No significant difference in Mf was observed between female and male newborns. Multivariable Poisson regression analysis revealed that increased HPRT Mf were significantly associated with maternal consumption of alcohol at the beginning [Relative Rate (RR) = 1.84, 95% CI = 0.99-3.40, P = 0.052) and during pregnancy (RR = 2.99, 95% CI = 1.14-7.84, P = 0.026). No independent effect of self-reported active maternal cigarette smoking, either at the beginning or throughout pregnancy, nor maternal passive exposure to cigarette smoke was observed. Although based on limited initial data, this is the first report of a positive association between maternal alcohol consumption during pregnancy and HPRT Mf in human newborns. In addition, the spectrum of mutations at the HPRT locus was determined in 33 mutant clones derived from 19 newborns of mothers with no self-reported exposure to tobacco smoke and 14 newborns of mothers exposed passively or actively to cigarette smoke. In the unexposed group, alterations leading to specific exon 2-3 deletions, presumably as a result of illegitimate V(D)J recombinase activity, were found in five of the 19 mutants (26.3%); in the passively exposed group, two exon 2-3 deletions were present among the seven mutants (28.6%); and in the actively exposed group, six of the seven mutants (85.7%) were exon 2-3 deletions. Although no overall increase in HPRT Mf was observed and the number of mutant clones examined was small, these initial results point to an increase in V(D)J recombinase-associated HPRT gene exon 2-3 deletions in cord blood T-lymphocytes in newborns of actively smoking mothers relative to unexposed mothers (P = 0.011). Together, these results add to growing molecular evidence that in utero exposures to genotoxicants result in detectable transplacental mutagenic effects in human newborns.


Assuntos
Hipoxantina Fosforribosiltransferase/genética , Mutação , Consumo de Bebidas Alcoólicas , DNA Nucleotidiltransferases/genética , DNA Nucleotidiltransferases/metabolismo , Etnicidade , Feminino , Sangue Fetal/fisiologia , Humanos , Recém-Nascido , Masculino , Mães , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Fumar , Fatores Socioeconômicos , VDJ Recombinases
8.
Arch Intern Med ; 158(15): 1695-701, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9701104

RESUMO

BACKGROUND: It is important to determine if permanent lifestyle changes may result from physical activity interventions and whether health may be affected by these changes. OBJECTIVE: To conduct a 10-year follow-up of physical activity and self-reported health status in participants of a randomized clinical trial of walking intervention. METHODS: Of the original 229 volunteer postmenopausal women who participated in the original clinical trial, 196 (N = 96 intervention and 100 controls) completed the 10-year follow-up telephone interview. The interview protocol included questions on self-reported walking for exercise and purposes other than exercise, the Paffenbarger sport and exercise index, functional status, and various chronic diseases and conditions. RESULTS: The median values for both usual walking for exercise and total walking were significantly higher for walkers compared with controls (for both, P = .01), with median differences of 706 and 420 kcal/wk, respectively. After excluding women who reported heart disease during the original trial, 2 women in the walking group (2%) and 11 women in the control group (12%) reported physician-diagnosed heart disease over the last 10 years (P = .07). There were also fewer hospitalizations, surgeries, and falls among women in the walking group, although these differences were not statistically significant (P>.05). CONCLUSIONS: Although limited by self-report, this study may be the first to demonstrate long-term exercise compliance to a randomized control trial in older women and to suggest that health benefits may have ensued as a result of these increased activity levels.


Assuntos
Doenças Cardiovasculares/epidemiologia , Pós-Menopausa , Caminhada , Idoso , Doenças Cardiovasculares/prevenção & controle , Feminino , Seguimentos , Nível de Saúde , Inquéritos Epidemiológicos , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Fatores de Tempo
10.
Clin Podiatr Med Surg ; 15(1): 139-50, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9463775

RESUMO

With the ever-increasing availability of wound care materials for use in diabetic foot ulcerations, a thorough understanding of the indications and applications of these materials is important for wound-management success. The coupling of a lack of understanding of the interaction of wound care materials and the dynamic nature of wound-healing physiology may lead to a protracted healing course that may constitute an abuse of an otherwise useful adjunct to wound healing protocols. This article provides an overview of wound care products, their indications, and possible complications of inappropriate use.


Assuntos
Bandagens , Pé Diabético/terapia , Administração Tópica , Bandagens/efeitos adversos , Desbridamento/métodos , Detergentes/uso terapêutico , Pé Diabético/complicações , Pé Diabético/fisiopatologia , Terapia Enzimática , Substâncias de Crescimento/administração & dosagem , Humanos , Cicatrização/fisiologia
12.
Am J Ind Med ; 31(1): 21-7, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8986250

RESUMO

The present case-control study was conducted in an effort to determine if work in the chemical industry is related to excesses of certain hematopoietic and lymphoid neoplasms. Cases who died from non-Hodgkin's lymphoma, multiple myeloma, and leukemia were matched by race, gender, age, year of death, and county of residence to controls who died from cardiovascular disease. A total of 618 (309 matched pairs) white male residents of Kanawha County, WV, aged 23-96, who had died between 1965 and 1990 were identified. Conditional logistic regression was conducted and yielded an association between chemical industry work and death due to non-Hodgkin's lymphoma, multiple myeloma, and lymphoid leukemia among subjects who died at age < 65. These results are consistent with the findings of previous studies linking work in chemical manufacturing to hematopoietic and lymphoid neoplasms, and indicate that the excesses may be related to the occupational exposures in men who died at younger ages.


Assuntos
Indústria Química , Leucemia/mortalidade , Linfoma não Hodgkin/mortalidade , Mieloma Múltiplo/mortalidade , Exposição Ocupacional/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Humanos , Leucemia/induzido quimicamente , Modelos Logísticos , Linfoma não Hodgkin/induzido quimicamente , Masculino , Mieloma Múltiplo/induzido quimicamente , Doenças Profissionais/induzido quimicamente , Doenças Profissionais/mortalidade , Fatores de Risco
13.
Clin Podiatr Med Surg ; 13(4): 759-66, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8902342

RESUMO

Cellulitis occurring in the lower extremity is encountered frequently and results from a breach of the skin and inoculation of opportunistic bacteria. It has been shown that when web space dermatophytosis is present, changes may occur in normal skin morphology and bacterial flora that can result in severe infection. Knowledge of the pathophysiology of interdigital dermatophytosis allows the clinician to choose the most appropriate empiric antibiotic therapy when treating a secondarily caused cellulitis of the lower extremity.


Assuntos
Celulite (Flegmão)/microbiologia , Dermatomicoses/complicações , Dedos do Pé/microbiologia , Idoso , Antifúngicos/uso terapêutico , Celulite (Flegmão)/tratamento farmacológico , Dermatomicoses/tratamento farmacológico , Dermatomicoses/microbiologia , Doenças do Pé/complicações , Doenças do Pé/microbiologia , Bactérias Gram-Negativas , Humanos , Tinha dos Pés/complicações
14.
Clin Podiatr Med Surg ; 13(2): 201-6, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9118010

RESUMO

Interdigital corns or soft corns are the accumulation of spongy, hyperkeratotic, circumscribed tissue between opposing surfaces of adjacent digits of the foot. The authors discuss the incidence, causes, locations, and treatment of these interdigital corns.


Assuntos
Calosidades/diagnóstico , Calosidades/cirurgia , Dermatoses do Pé/diagnóstico , Dermatoses do Pé/cirurgia , Calosidades/etiologia , Calosidades/patologia , Pé/patologia , Dermatoses do Pé/etiologia , Dermatoses do Pé/patologia , Humanos
16.
Sci Total Environ ; 127(1-2): 139-54, 1992 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-1480952

RESUMO

There has been much concern recently about possible adverse health effects related to exposure to toxic chemicals among residents of Kanawha County in southern West Virginia. An epidemiological study of trends in cancer mortality from 1950-1984 among the general population of Kanawha County in southern West Virginia was mounted. Cabell County, West Virginia was chosen to be a comparison county for Kanawha in addition to West Virginia and the total United States. The cancer mortality rates for white males and females were calculated using NCHS mortality data and Census Bureau population data available on the Mortality and Population Data System (MPDS) at the University of Pittsburgh. Mortality rates for cancer in Kanawha and Cabell Counties were evaluated over the time period 1950-1984 with an age-period-cohort (APC) analysis. In this analysis, poisson regression models were fit using the statistical program GLIM (Generalized Linear Models) to determine the separate effects of age, period of death, and birth cohort on the specific cancers of interest (lung, liver, bladder, CNS, leukemia, lympho-reticulosarcoma, all cancers). There were no significant county differences for cancer death rates between Kanawha and Cabell Counties except for leukemia among white males [O.R. = 1.27, 95% (C.I. = 1.03-1.6)], and for lympho-reticulosarcoma [O.R. = 1.66(1.24-2.07)], suggesting a possible occupational exposure. For leukemia, aleukemia, the effect observed seems to have declined. In contrast, the elevation of lympho-reticulosarcoma rates has remained in recent years (1970-1984).


Assuntos
Poluentes Atmosféricos/efeitos adversos , Indústria Química , Leucemia/mortalidade , Linfoma Difuso de Grandes Células B/mortalidade , Exposição Ocupacional/efeitos adversos , Adolescente , Adulto , Causas de Morte , Feminino , Humanos , Leucemia/induzido quimicamente , Linfoma Difuso de Grandes Células B/induzido quimicamente , Masculino , West Virginia/epidemiologia
17.
J Occup Med ; 32(8): 690-7, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2401923

RESUMO

The present study assessed the relationships among occupational noise exposure, noise-induced hearing loss, and high blood pressure. The study population consisted of 245 retired metal assembly workers from Pittsburgh aged 56 to 68 with chronic noise exposure of 30 or more years at greater than or equal to 89 dBA. Results of the audiometric testing indicated 52% of the younger workers (ages 56 to 63) have severe noise-induced hearing loss (greater than or equal to 65 dBA loss at 3, 4, or 6 kHz) and 67% of older workers (ages 64 to 68). Body mass index and alcohol intake were significantly related to systolic and diastolic blood pressure. Among older men, there was a marginally significant increased prevalence of high blood pressure (greater than or equal to 90 mm diastolic or taking blood pressure medicine) among those with severe noise-induced hearing loss (P = .05). Moreover, another measure of hearing loss at high frequencies, speech discrimination score in noise (measured in the better ear), referred to as the W-22 MAX score, was also found to be related to the prevalence of high blood pressure in the older (64 to 68) age group (P less than .05). Multiple regression analysis revealed W-22 MAX and severe noise-induced hearing loss were independent predictors of hypertension in the older, but not in the younger group of retired workers.


Assuntos
Perda Auditiva Provocada por Ruído/etiologia , Hipertensão/epidemiologia , Ruído/efeitos adversos , Doenças Profissionais/etiologia , Fatores Etários , Idoso , Consumo de Bebidas Alcoólicas , Índice de Massa Corporal , Estudos de Coortes , Perda Auditiva Provocada por Ruído/diagnóstico , Perda Auditiva Provocada por Ruído/epidemiologia , Humanos , Hipertensão/diagnóstico , Hipertensão/etiologia , Masculino , Metalurgia , Pessoa de Meia-Idade , Doenças Profissionais/diagnóstico , Doenças Profissionais/epidemiologia , Pennsylvania/epidemiologia , Fatores de Risco
18.
Appl Opt ; 26(22): 4875-82, 1987 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-20523462

RESUMO

This paper describes numerical procedures for data reduction of full spheres from interferometric data taken at various positions around the surface of the sphere. The technique allows the use of practical f/No. optics, incomplete coverage or overlap of the interferograms, and differences in optical alignment of each interferogram.

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