Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Biodivers Data J ; (5): e11778, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28765721

RESUMEN

BACKGROUND: A survey of the understory bryophytes in the Nectandra Cloud Forest Preserve yielded 1083 specimens distributed among 55 families, represented by 74 genera of mosses, 75 genera of liverworts and 3 of hornworts. We studied and analyzed the bryophytic distribution on six types of substrates: 1) corticolous, 2) epiphyllous, 3) saxicolous, 4) terricolous, 5) aquatic and 6) lignicolous. The richness and composition of bryophyte genera are compared to those of other previous bryophyte surveys from 4 other sites with different oceanic exposures, climatic and geographic conditions in Costa Rica. NEW INFORMATION: This is a report of the first extensive general survey of bryophytes at the Nectandra Reserve, a premontane cloud forest located on the Atlantic slope of Costa Rica, an area much less studied compared to the Monteverde cloud forest on the Pacific slope.

2.
Blood ; 120(18): 3750-5, 2012 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-22972983

RESUMEN

An altered anti-Epstein-Barr virus (EBV) serologic profile preceding diagnosis is associated with an increased risk of Hodgkin lymphoma. It is unknown whether this atypical pattern predicts Hodgkin lymphoma risk further subdivided by determination of EBV in tumor cells. A nested case-control study of 128 incident Hodgkin lymphoma cases and 368 matched controls from active-duty military personnel with archived serum in the US Department of Defense Serum Repository was conducted to determine whether a panel of anti-EBV antibody titers differed in EBV(+) and EBV(-) Hodgkin lymphoma. Among 40 EBV(+) Hodgkin lymphoma cases and matched controls, statistically significant increased risks were associated with elevated anti-EBV VCA IgG antibody titers (relative risk = 3.1; 95% confidence interval [CI], 1.1-8.7), and an anti-EBNA-1/anti-EBNA-2 antibody ratio ≤ 1.0 versus > 1.0 (relative risk = 4.7; 95% CI, 1.6-13.8). In contrast, no significant associations were found among 88 EBV(-) Hodgkin lymphoma cases relative to their matched controls. In case-case analysis, EBV(+) disease was significantly associated with a low anti-EBNA-1/anti-EBNA-2 antibody ratio. This distinctive serologic response to EBV latent antigens, indicative of immune dysfunction in other clinical settings, is associated with an increased risk of developing EBV(+) but not EBV(-) Hodgkin lymphoma.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/sangre , Enfermedad de Hodgkin/sangre , Adolescente , Adulto , Estudios de Casos y Controles , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/virología , Femenino , Herpesvirus Humano 4/inmunología , Enfermedad de Hodgkin/inmunología , Enfermedad de Hodgkin/virología , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
3.
Int J Cancer ; 130(12): 2886-91, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-21805472

RESUMEN

A role for Epstein Barr virus (EBV) in Hodgkin lymphoma (HL) pathogenesis is supported by the detection of EBV genome in about one-third of HL cases, but is not well defined. We previously reported that an elevated prediagnosis antibody titer against EBV nuclear antigens (EBNA) was the strongest serologic predictor of subsequent HL. For the present analysis, we measured antibody levels against EBNA components EBNA1 and EBNA2 and computed their titer ratio (anti-EBNA1:2) in serum samples from HL cases and healthy siblings. We undertook this analysis to examine whether titer patterns atypical of well-resolved EBV infection, such as an anti-EBNA1:2 ratio ≤ 1.0, simply reflect history of infectious mononucleosis (IM), an HL risk factor, or independently predict HL risk. Participants were selected from a previous population-based case-control study according to their history of IM. We identified 55 EBV-seropositive persons with a history of IM (IM+; 33 HL cases, 22 siblings) and frequency-matched a comparison series of 173 IM history-negative, EBV-seropositive subjects on HL status, gender, age and year of blood draw (IM-; 105 cases, 58 siblings). In multivariate logistic regression models, an anti-EBNA1:2 ratio ≤ 1.0 was significantly more prevalent in HL cases than siblings (odds ratio, 95% confidence interval = 2.43, 1.05-5.65); similar associations were apparent within the IM+ and IM- groups. EBNA antibodies were not significantly associated with IM history in HL cases or siblings. These associations suggest that chronic or more severe EBV infection is a risk factor for HL, independent of IM history.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/inmunología , Antígenos Nucleares del Virus de Epstein-Barr/inmunología , Herpesvirus Humano 4/inmunología , Enfermedad de Hodgkin/virología , Proteínas Virales/inmunología , Adulto , Anticuerpos Antivirales/inmunología , Femenino , Herpesvirus Humano 4/genética , Enfermedad de Hodgkin/inmunología , Humanos , Mononucleosis Infecciosa/inmunología , Mononucleosis Infecciosa/virología , Masculino , Adulto Joven
4.
Cancer Sci ; 99(2): 350-4, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18201267

RESUMEN

We evaluated associations between Epstein-Barr virus (EBV) antibody levels and precancerous gastric lesions (chronic atrophic gastritis, intestinal metaplasia, and dysplasia) in 183 subjects from Linqu, China. Immunoglobulin G antibody titers to EBV nuclear antigen (EBNA) and viral capsid antigen (VCA) were determined by two-fold serial dilution using immunofluorescence assays. Histological progression and regression were assessed by gastroscopic examination at the time of phlebotomy and at follow up 2 years later. Antibody titers did not differ significantly among histological diagnoses determined at the time of phlebotomy. However, subjects with dysplasia at follow up had significantly higher geometric mean antibody titers for both anti-VCA and anti-EBNA. Subjects with greater than median antibody levels were more likely to progress between examinations, especially in the subgroup with intestinal metaplasia at the time of phlebotomy (odds ratios [95% confidence intervals]: 5.7 [1.6-20] for anti-EBNA >or=1:320; 3.8 [1.0-15] for anti-VCA >or=1:640). Our findings suggest a possible role for EBV reactivation at an early phase of gastric carcinogenesis.


Asunto(s)
Anticuerpos Antivirales/sangre , Herpesvirus Humano 4/inmunología , Lesiones Precancerosas/virología , Neoplasias Gástricas/virología , Adulto , China , Estudios de Cohortes , Infecciones por Virus de Epstein-Barr/inmunología , Antígenos Nucleares del Virus de Epstein-Barr/inmunología , Femenino , Gastritis Atrófica/patología , Humanos , Intestinos/patología , Masculino , Metaplasia , Persona de Mediana Edad , Lesiones Precancerosas/inmunología , Lesiones Precancerosas/patología , Estómago/anomalías , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/patología
5.
AIDS Res Hum Retroviruses ; 21(10): 869-75, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16225414

RESUMEN

One hundred twenty-three subjects with documented HIV-1 primary infection were followed for over a year; 96 received highly active antiretroviral therapy (HAART) at recruitment; 27 declined treatment. Fifty uninfected subjects served as baseline controls. HIV-1 viral load, CD4 and CD8 T cell numbers, and serologic changes to Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), human herpesvirus 8 (HHV-8), and cytomegalovirus (CMV) were monitored. Although responses to HAART varied, herpesvirus reactivation frequencies did not differ relative to HIV-1 virologic responses. Forty-seven subjects had reactivations to a single herpesvirus type and 12 subjects to > or =2 types; no single herpesvirus dominated. Antibody seroprevalence to EBV, HHV-6, and CMV were similar but HHV-8 infection was twice as prevalent in HIV-1-infected vs. uninfected individuals. Notably, lower HIV-1 viremia (7,313 vs. 55,548 geometric mean RNA copies/ml) at baseline was significantly associated with HHV-8 seropositivity (p < 0.004).


Asunto(s)
Infecciones por VIH/virología , Infecciones por Herpesviridae/complicaciones , Herpesviridae/fisiología , Terapia Antirretroviral Altamente Activa , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , VIH-1/genética , VIH-1/aislamiento & purificación , Herpesviridae/clasificación , Herpesviridae/aislamiento & purificación , Humanos , Carga Viral , Activación Viral
6.
JAMA ; 293(20): 2496-500, 2005 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-15914750

RESUMEN

CONTEXT: Infection with Epstein-Barr virus (EBV) has been associated with an increased risk of multiple sclerosis (MS), but the temporal relationship remains unclear. OBJECTIVE: To determine whether antibodies to EBV are elevated before the onset of MS. DESIGN, SETTING, AND PARTICIPANTS: Nested case-control study conducted among more than 3 million US military personnel with blood samples collected between 1988 and 2000 and stored in the Department of Defense Serum Repository. Cases were identified as individuals granted temporary or permanent disability because of MS. For each case (n = 83), 2 controls matched by age, sex, race/ethnicity, and dates of blood sample collection were selected. Serial samples collected before the onset of symptoms were available for 69 matched case-control sets. MAIN OUTCOME MEASURES: Antibodies including IgA against EBV viral capsid antigen (VCA), and IgG against VCA, nuclear antigens (EBNA complex, EBNA-1, and EBNA-2), diffuse and restricted early antigens, and cytomegalovirus. RESULTS: The average time between blood collection and MS onset was 4 years (range, <1-11 years). The strongest predictors of MS were serum levels of IgG antibodies to EBNA complex or EBNA-1. Among individuals who developed MS, serum antibody titers to EBNA complex were similar to those of controls before the age of 20 years (geometric mean titers: cases = 245, controls = 265), but 2- to 3-fold higher at age 25 years and older (cases = 684, controls = 282; P<.001). The risk of MS increased with these antibody titers; the relative risk (RR) in persons with EBNA complex titers of at least 1280 compared with those with titers less than 80 was 9.4 (95% confidence interval [CI], 2.5-35.4; P for trend <.001). In longitudinal analyses, a 4-fold increase in anti-EBNA complex or anti-EBNA-1 titers during the follow-up was associated with a 3-fold increase in MS risk (EBNA complex: RR , 3.0; 95% CI, 1.3-6.5; EBNA-1: RR, 3.0; 95% CI, 1.2-7.3). No association was found between cytomegalovirus antibodies and MS. CONCLUSION: These results suggest an age-dependent relationship between EBV infection and development of MS.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/inmunología , Herpesvirus Humano 4/inmunología , Esclerosis Múltiple/virología , Adulto , Estudios de Casos y Controles , Infecciones por Virus de Epstein-Barr/fisiopatología , Antígenos Nucleares del Virus de Epstein-Barr/inmunología , Femenino , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Estudios Longitudinales , Masculino , Personal Militar , Esclerosis Múltiple/sangre , Esclerosis Múltiple/fisiopatología , Factores de Riesgo , Estados Unidos
7.
Cancer Epidemiol Biomarkers Prev ; 13(8): 1385-91, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15298962

RESUMEN

We assessed the informativeness of several serologic biomarkers of immune function using serum specimens collected in the Miyazaki Cohort Study from subjects who were seronegative for anti-human T-cell lymphotrophic virus I and anti-hepatitis C virus. To broadly characterize type 1 immune status, we measured EBV antibody titers, because titer profiles associated with cellular immune suppression are well described. We also tested for three type 2 biomarkers: total serum IgE, soluble CD23, and soluble CD30. Nonreactivity to a tuberculin purified protein derivative (PPD) skin test is indicative of diminished delayed-type hypersensitivity (type 1) responsiveness in the study population due to a history of tuberculosis exposure or Bacillus Calmette-Guérin vaccination. We therefore evaluated the serologic markers as predictors of PPD nonreactivity using logistic regression. Subjects whose EBV antibody profiles were consistent with deficient type 1 immunity were more than thrice as likely to be PPD nonreactive as persons with "normal" antibody titers. Elevated total IgE was also strongly associated with PPD nonreactivity (odds ratio 3.4, 95% confidence interval 1.2-9.9); elevated soluble CD23 had a weaker, but positive, odds ratio, whereas soluble CD30 levels were not predictive of PPD status. Therefore, PPD nonreactivity is associated, in this population, with a pattern of serum biomarkers that is indicative of diminished type 1 and elevated type 2 immunity. We conclude that, with the exception of soluble CD30, the serologic markers are informative for the characterization of type 1/type 2 immune status using archived sera from study populations of healthy adults.


Asunto(s)
Anticuerpos Anti-HTLV-I/sangre , Infecciones por HTLV-I/inmunología , Anticuerpos contra la Hepatitis C/sangre , Hepatitis C/inmunología , Inmunidad Celular/fisiología , Adulto , Distribución por Edad , Biomarcadores/análisis , Estudios de Cohortes , Intervalos de Confianza , Femenino , Infecciones por HTLV-I/diagnóstico , Infecciones por HTLV-I/epidemiología , Hepatitis C/diagnóstico , Hepatitis C/epidemiología , Humanos , Incidencia , Japón/epidemiología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Estudios Prospectivos , Valores de Referencia , Medición de Riesgo , Población Rural , Pruebas Serológicas , Distribución por Sexo , Prueba de Tuberculina
8.
J Infect Dis ; 189(12): 2271-81, 2004 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-15181575

RESUMEN

BACKGROUND: Hodgkin lymphoma (HL) tumors that contain the Epstein-Barr virus (EBV) genome may differ etiologically from EBV-negative HL tumors. METHODS: A case-case study examining heterogeneity of risk factors between disease subgroups compared personal characteristics and EBV antibodies between 95 EBV-positive and 303 EBV-negative patients with HL. RESULTS: We confirmed previous associations of EBV-positive HL with older age, male sex, and mixed-cellularity (MC) histological subtypes. EBV-positive patients were less educated and more likely to have smoked cigarettes and had more prevalent and higher EBV antibody titers, compared with EBV-negative patients. After adjustment for all independent risk factors, those most strongly associated with EBV-positive HL were histological subtypes (odds ratio [OR] for MC vs. nodular sclerosis histology, 3.2; 95% confidence interval [CI], 1.4-7.2), elevated anti-viral capsid antigen level (OR, 3.1; 95% CI, 1.6-6.0), and less education (OR, 0.7; 95% CI, 0.5-1.0). Cigarette smoking and a low anti-Epstein-Barr nuclear protein (EBNA) 1 : anti-EBNA-2 ratio were also marginally associated with EBV-positive HL. CONCLUSIONS: EBV-positive HL is more common among individuals who have markers of diminished cellular immunity and an abnormal EBV antibody response. EBV appears to participate in the etiology of EBV-positive HL but may not be involved in EBV-negative HL.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/virología , Genoma Viral , Herpesvirus Humano 4/inmunología , Herpesvirus Humano 4/aislamiento & purificación , Enfermedad de Hodgkin/virología , Adolescente , Adulto , Anciano , Infecciones por Virus de Epstein-Barr/epidemiología , Femenino , Herpesvirus Humano 4/genética , Enfermedad de Hodgkin/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
9.
JAMA ; 289(12): 1533-6, 2003 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-12672770

RESUMEN

CONTEXT: Infection with Epstein-Barr virus (EBV) has been associated with an increased risk of multiple sclerosis (MS), but the temporal relationship remains unclear. OBJECTIVE: To determine whether antibodies to EBV are elevated before the onset of MS. DESIGN, SETTING, AND POPULATION: Nested case-control study conducted among more than 3 million US military personnel with blood samples collected between 1988 and 2000 and stored in the Department of Defense Serum Repository. Cases were identified as individuals granted temporary or permanent disability because of MS. For each case (n = 83), 2 controls matched by age, sex, race/ethnicity, and dates of blood sample collection were selected. MAIN OUTCOME MEASURES: Antibodies including IgA against EBV viral capsid antigen (VCA) and IgG against VCA, nuclear antigens (EBNA complex, EBNA-1, and EBNA-2), diffuse and restricted early antigens, and cytomegalovirus. RESULTS: The average time between blood collection and MS onset was 4 years. The strongest predictors of MS were serum levels of IgG antibodies to VCA or EBNA complex. The risk of MS increased monotonically with these antibody titers; relative risk (RR) in persons in the highest category of VCA (> or =2560) compared with those in the lowest (< or =160) was 19.7 (95% confidence interval [CI], 2.2-174; P for trend =.004). For EBNA complex titers, the RR for those in the highest category (> or =1280) was 33.9 (95% CI, 4.1-283; P for trend <.001) vs those in the lowest category (< or =40). Similarly strong positive associations between EBV antibodies and risk of MS were already present in samples collected 5 or more years before MS onset. No association was found between cytomegalovirus antibodies and MS. CONCLUSION: These results suggest a relationship between EBV infection and development of MS.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/fisiopatología , Herpesvirus Humano 4/inmunología , Esclerosis Múltiple/virología , Adolescente , Adulto , Antígenos Virales/inmunología , Proteínas de la Cápside/inmunología , Estudios de Casos y Controles , Citomegalovirus/inmunología , Antígenos Nucleares del Virus de Epstein-Barr/inmunología , Femenino , Humanos , Inmunoglobulina A/inmunología , Inmunoglobulina G/inmunología , Masculino , Esclerosis Múltiple/inmunología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...