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1.
J Clin Microbiol ; 53(1): 52-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25339396

RESUMEN

The effective management of women with human papillomavirus (HPV)-positive, cytology-negative results is critical to the introduction of HPV testing into cervical screening. HPV typing has been recommended for colposcopy triage, but it is not clear which combinations of high-risk HPV types provide clinically useful information. This study included 18,810 women with Hybrid Capture 2 (HC2)-positive, cytology-negative results and who were age ≥30 years from Kaiser Permanente Northern California. The median follow-up was 475 days (interquartile range [IQR], 0 to 1,077 days; maximum, 2,217 days). The baseline specimens from 482 cases of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) and 3,517 random HC2-positive noncases were genotyped using 2 PCR-based methods. Using the case-control sampling fractions, the 3-year cumulative risks of CIN3+ were calculated for each individual high-risk HPV type. The 3-year cumulative risk of CIN3+ among all women with HC2-positive, cytology-negative results was 4.6%. HPV16 status conferred the greatest type-specific risk stratification; women with HC2-positive/HPV16-positive results had a 10.6% risk of CIN3+, while women with HC-2 positive/HPV16-negative results had a much lower risk of 2.4%. The next most informative HPV types and their risks in HPV-positive women were HPV33 (5.9%) and HPV18 (5.9%). With regard to the etiologic fraction, 20 of 71 cases of cervical adenocarcinoma in situ (AIS) and adenocarcinoma in the cohort were positive for HPV18. HPV16 genotyping provides risk stratification useful for guiding clinical management; the risk among HPV16-positive women clearly exceeds the U.S. consensus risk threshold for immediate colposcopy referral. HPV18 is of particular interest because of its association with difficult-to-detect glandular lesions. There is a less clear clinical value of distinguishing the other high-risk HPV types.


Asunto(s)
Cuello del Útero/virología , Genotipo , Papillomaviridae/clasificación , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Colposcopía , Detección Precoz del Cáncer , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Tipificación Molecular , Prueba de Papanicolaou , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/epidemiología , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/etiología , Displasia del Cuello del Útero/diagnóstico , Displasia del Cuello del Útero/epidemiología , Displasia del Cuello del Útero/etiología
2.
Nat Genet ; 6(2): 157-62, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8162070

RESUMEN

Cervical carcinoma is now known to be associated with human papillomaviruses (HPV), but the evidence for a link with specific HLA loci is controversial. The role of genetic variation at the HLA class II loci and among HPV types in cervical carcinoma was investigated by PCR DNA amplification and oligonucleotide probe typing of paraffin-embedded invasive cervical cancer tissue from Hispanic patients and of cervical swabs from Hispanic controls. Certain HLA class II haplotypes (such as DRB1*1501-DQB1*0602) were associated significantly, while DR13 haplotypes were negatively associated with cervical carcinoma. These associations are HPV16-type specific. These results suggest that specific HLA class II haplotypes may influence the immune response to specific HPV-encoded epitopes and affect the risk of cervical neoplasia.


Asunto(s)
Adenocarcinoma/inmunología , Carcinoma de Células Escamosas/inmunología , Antígenos HLA-DQ/análisis , Antígenos HLA-DR/análisis , Papillomaviridae/fisiología , Neoplasias del Cuello Uterino/inmunología , Adenocarcinoma/epidemiología , Adenocarcinoma/virología , Carcinoma de Células Escamosas/virología , Estudios de Casos y Controles , Susceptibilidad a Enfermedades , Femenino , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Haplotipos , Hispánicos o Latinos , Prueba de Histocompatibilidad , Humanos , Oportunidad Relativa , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/virología , Reacción en Cadena de la Polimerasa , Sudoeste de Estados Unidos , Infecciones Tumorales por Virus/inmunología , Infecciones Tumorales por Virus/virología , Neoplasias del Cuello Uterino/virología
3.
Nat Med ; 2(4): 405-11, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8597949

RESUMEN

Major histocompatibility complex (MHC) genes (HLA in humans) regulate the immune response to foreign antigens. Molecular and serologic techniques were used to identify products of HLA class I, class II and transporter (TAP) genes (also part of the MHC) in homosexual seroconverters to human immunodeficiency virus type 1 (HIV-1). Comprehensive statistical analysis produced an HLA profile that predicted time from HIV-1 infection to the onset of AIDS. The profile was developed in a cohort of 139 men and evaluated in a second unrelated cohort of 102 men. In the evaluation cohort, the profile discriminated a sixfold difference between groups with the shortest and longest times to AIDS (P = 0.001). These findings support current theory about control of antigen processing by HLA genes and have implications for immunopathogenesis of HIV-1 and other infections.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Infecciones por VIH/genética , VIH-1/aislamiento & purificación , Complejo Mayor de Histocompatibilidad/genética , Estudios de Cohortes , Ligamiento Genético , Infecciones por VIH/inmunología , Infecciones por VIH/mortalidad , Antígenos de Histocompatibilidad Clase I/análisis , Antígenos de Histocompatibilidad Clase II/análisis , Humanos , Masculino , Análisis de Supervivencia
4.
J Exp Med ; 178(5): 1675-80, 1993 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8228814

RESUMEN

How peptide-major histocompatibility complex (MHC) class II complexes are naturally generated is still unknown, but accumulating evidence suggests that unfolding proteins or long peptides can become bound to class II molecules at the dominant determinant before proteolytic cleavage. We have compared the immunogenicity of hen egg-white lysozyme (HEL) in nonobese diabetic (NOD), (NOD x BALB/c)F1, and E(d) alpha transgenic NOD mice. We find that a response to the subdominant ANOD-restricted determinant disappears upon introduction of an E(d) molecule, and is restored when scission of HEL separates this determinant from its adjoining, competitively dominant, E(d)-restricted determinant. This suggests that the E(d) molecule binds and protects its dominant determinant on a long peptide while captured neighboring determinants are lost during proteolysis. These results provide clear evidence for "determinant capture" as a mechanism of determinant selection during antigen processing and a possible explanation for MHC-protective effects in insulin-dependent diabetes mellitus.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Linfocitos T/inmunología , Animales , Antígenos de Histocompatibilidad Clase II/metabolismo , Inmunización , Activación de Linfocitos , Complejo Mayor de Histocompatibilidad , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NOD , Ratones Transgénicos , Muramidasa/inmunología , Fragmentos de Péptidos/inmunología
5.
J Exp Med ; 173(3): 609-17, 1991 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-1705279

RESUMEN

T lymphocytes recognize discrete regions on an antigen. The specificity of the T cell responses in three mouse strains of differing major histocompatibility complex (MHC) haplotype to a protein antigen, lysozyme, was analyzed using a series of peptides that walk the antigen in single amino acid steps. These peptide series were synthesized using the pin synthesis system, which was modified to allow the peptides to be cleaved from the pins into a physiological buffer free of toxic compounds. This methodology overcomes many of the problems associated with the production of peptides for screening proteins for antigenic determinants. The T cell determinants for the three strains were markedly different. This result points out the limitations of algorithms predicting determinants without reference to the MHC, and the importance of the empirical methodology. This analysis of the T cell response to lysozyme constitutes the most complete study of reactivity to a foreign protein to date and illustrates many important features of antigen recognition by T cells, e.g., presence of major and minor determinant regions. The outer boundaries of each immunogenic region, the determinant envelope, are difficult to define from recently immunized lymph nodes because of the heterogeneity in T cell recognition. However, core sequences common to all the immunogenic peptides in a continuous sequence can be easily defined.


Asunto(s)
Haplotipos , Complejo Mayor de Histocompatibilidad , Muramidasa/inmunología , Linfocitos T/inmunología , Secuencia de Aminoácidos , Animales , Aves , Epítopos/análisis , Hibridomas/inmunología , Ganglios Linfáticos/inmunología , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos , Datos de Secuencia Molecular , Muramidasa/genética , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
6.
Science ; 280(5366): 1073-7, 1998 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-9582120

RESUMEN

Detection of human immunodeficiency virus-type 1 (HIV-1) on only one or a few occasions in infants born to infected mothers has been interpreted to indicate that infection may be transient rather than persistent. Forty-two cases of suspected transient HIV-1 viremia among 1562 perinatally exposed seroreverting infants and one mother were reanalyzed. HIV-1 env sequences were not found in specimens from 20; in specimens from 6, somatic genetic analysis revealed that specimens were mistakenly attributed to an infant; and in specimens from 17, phylogenetic analysis failed to demonstrate the expected linkage between the infant's and the mother's virus. These findings argue that transient HIV-1 infection, if it exists, will only rarely be satisfactorily documented.


Asunto(s)
Infecciones por VIH/virología , VIH-1/genética , VIH-1/aislamiento & purificación , Manejo de Especímenes , ADN Viral/análisis , ADN Viral/genética , Errores Diagnósticos , Contaminación de Equipos , Femenino , Genes env , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Linfocitos T Citotóxicos/inmunología , Viremia/virología
7.
Obes Sci Pract ; 4(5): 417-426, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30338112

RESUMEN

OBJECTIVE: There are conflicting data regarding the association between body mass index (BMI) and health-related quality of life (HRQoL), especially among certain population subgroups and for mental and physical health domains. METHODS: This study analysed the relationship between BMI and HRQoL (Patient-Reported Outcomes Measurement Information System mental and physical health scales) using ordinary least squares regression. Each model allowed for the possibility of a non-linear relationship between BMI and the outcome, adjusting for age, gender, comorbidities, diet and physical activity. RESULTS: A total of 10,133 respondents were predominantly female (71.7%), White (84.1%), median age of 52.1 years (interquartile range 37.2-63.3) and median BMI of 27.9 (interquartile range 24.0-33.2). In adjusted models, BMI was significantly associated with physical and mental HRQoL (p < 0.001). For physical HRQoL, there was a significant interaction with age (p = 0.02). For mental HRQoL, there was a significant interaction with sex (p = 0.0004) but not age (p = 0.7). CONCLUSIONS: This study demonstrates a non-linear association of variable clinical relevance between BMI and HRQoL after adjusting for demographic factors and comorbidities. The relationship between BMI and HRQoL is nuanced and impacted by gender and age. These findings challenge the idea of obesity as a main driver of reduced HRQoL, particularly among women and with respect to mental HRQoL.

8.
J Natl Cancer Inst ; 87(6): 427-36, 1995 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-7861462

RESUMEN

BACKGROUND: Human leukocyte antigen (HLA) molecules, whose biological role is in the regulation of immune responses to foreign antigens and in discrimination of self from non-self antigens, are encoded by a series of closely linked genetic loci found on chromosome 6. Although the evidence for a link between HLA and cervical cancer has been controversial, it has been recently reported that certain HLA class II haplotypes (linked class II alleles) are positively associated with invasive cervical cancer, while other class II haplotypes are negatively associated or protective. Since HLA associations between human papillomavirus type 16 (HPV16)-mediated cancer cases and non-HPV16-mediated cancer cases have been found to be different, this suggests that specific HLA class II haplotypes may influence the immune response to HPV infection and may affect the risk of acquiring invasive cervical carcinoma. PURPOSE: This study was conducted to determine if the same HLA class II haplotypes that are associated with invasive cervical carcinoma are also associated with cervical dysplasia (presumed precursors of invasive cervical cancer). METHODS: We have examined HLA DR-DQ haplotypes among 128 Hispanic women from New Mexico with biopsy-confirmed cervical dysplasia in a case-control study using sensitive DNA-based polymerase chain reaction amplification and sequence-specific oligonucleotide probe hybridization methods to detect the presence and type of HPV and to detect allelic polymorphism in the HLA DRB1 and DQB1 loci. RESULTS: Dysplasia cases were divided into two groups for comparison to controls: severe dysplasia/carcinoma in situ (CIS), and slight/moderate dysplasia. The frequency distribution of HLA class II haplotypes among the HPV16-positive severe dysplasia/CIS cases had a statistically significant (two-tailed P < .005) difference compared with controls, whereas haplotypes among the severe dysplasia/CIS cases containing HPV types other than HPV16 did not show statistically significant frequency differences. DR-DQ haplotypes previously found to be associated with HPV16-invasive cervical carcinomas were also associated with HPV16-positive severe dysplasia/CIS. However, no statistically significant haplotype frequency difference was observed between slight/moderate dysplasia cases and controls. In addition, we noted a DQA1-DQB1 haplotype negatively associated with severe dysplasia/CIS but not with invasive cervical cancers. CONCLUSIONS: Our results strongly suggest that certain HLA haplotypes confer an increased risk for severe cervical dysplasia and invasive cervical carcinoma following HPV16 infection. IMPLICATIONS: Further molecular studies are needed to identify HLA alleles or haplotypes that may provide increased susceptibility to HPV-associated cervical disease.


Asunto(s)
Antígenos HLA-DQ/sangre , Antígenos HLA-DR/sangre , Displasia del Cuello del Útero/inmunología , Neoplasias del Cuello Uterino/inmunología , Adulto , Estudios de Casos y Controles , Sondas de ADN , ADN de Neoplasias , Femenino , Haplotipos , Hispánicos o Latinos , Humanos , Invasividad Neoplásica , Hibridación de Ácido Nucleico , Papillomaviridae , Reacción en Cadena de la Polimerasa , Displasia del Cuello del Útero/virología , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología
9.
Arch Gen Psychiatry ; 48(8): 712-8, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1883254

RESUMEN

The comorbidity of psychiatric diagnoses was examined with the Diagnostic Interview Schedule in 62 women who participated in a 10-year follow-up study of anorexia nervosa. Sixty-two age- and sex-matched controls, their parents, and parents of the anorectic probands were also interviewed with the Diagnostic Interview Schedule. There was a statistically significant comorbidity of the affective and anxiety disorders with anorexia nervosa. The first-degree relatives of the anorectic probands had significantly more alcoholism and total number of psychiatric diagnoses compared with the first-degree relatives of controls. There were two mothers with bulimia nervosa, two cases of anorexia nervosa and two of bulimia nervosa in other first-degree relatives of anorectic probands, and no cases of eating disorders in the first-degree relatives of controls.


Asunto(s)
Anorexia Nerviosa/epidemiología , Trastornos Mentales/epidemiología , Adulto , Factores de Edad , Alcoholismo/diagnóstico , Alcoholismo/epidemiología , Alcoholismo/genética , Anorexia Nerviosa/diagnóstico , Anorexia Nerviosa/genética , Bulimia/diagnóstico , Bulimia/epidemiología , Bulimia/genética , Comorbilidad , Femenino , Estudios de Seguimiento , Humanos , Trastornos Mentales/diagnóstico , Trastornos Mentales/genética , Persona de Mediana Edad , Prevalencia , Escalas de Valoración Psiquiátrica , Factores Sexuales
10.
Mol Immunol ; 21(10): 901-5, 1984 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6209563

RESUMEN

The antigenic relationship between native and denatured bovine serum albumin (BSA) was investigated by examining specificity of antibodies directed against both proteins. Polyclonal antibodies produced to native and denatured BSA in hyperimmunized mice were specific for the homologous molecule. In contrast, polyclonal antibodies formed early in the response to native BSA reacted both the denatured and the native molecule. Monoclonal antibodies to native BSA were specific for the homologous antigen, while one of three clones prepared by immunization with denatured BSA produced an antibody cross-reactive with native BSA. Our results suggest that shared determinants of native and denatured BSA molecules can be recognized by both B- and T-cells.


Asunto(s)
Linfocitos B/inmunología , Epítopos/inmunología , Albúmina Sérica Bovina/inmunología , Linfocitos T/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Formación de Anticuerpos , Especificidad de Anticuerpos , Reacciones Cruzadas , Femenino , Ratones , Ratones Endogámicos , Desnaturalización Proteica
11.
AIDS ; 12(16): 2107-13, 1998 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-9833851

RESUMEN

BACKGROUND: Host genetic factors, such as HLA alleles, play an important role in mediating the course of HIV-1 disease progression through largely undefined mechanisms. OBJECTIVES: To examine the association of HLA markers with HIV-1 RNA plasma viral load and other factors associated with course of disease progression in HIV-1 infection. DESIGN AND METHODS: A group of 139 HIV-1 seroconverters from the Multicenter AIDS Cohort Study had been typed for a variety of HLA markers. HIV-1 RNA plasma viral load was measured from frozen plasma specimens obtained approximately 9 months following seroconversion. CD4+ cell counts were available from the same study visit. Statistical analysis was performed using survival techniques and linear regression models to quantify the relative associations of an HLA score profile, HIV-1 RNA plasma viral load, CD4+ cell count and age with each other and with rate of progression to AIDS and death. RESULTS: Cox proportional hazards models showed statistically significant differences in time to AIDS by HLA score profile category per unit increase [relative hazard (RH), 0.64; P < 0.0001], HIV-1 RNA plasma viral load per 10-fold increase (RH, 2.04; P = 0.0003), and CD4+ cell count per 100 cell (x 10(6)/l) increase (RH, 0.90; P = 0.02). Multivariate linear regression showed that viral load was 39% lower (P = 0.0001) for each unit increase in HLA score profile and 13% lower (P = 0.002) for each 100 cell (x 10(6)/l) increase in CD4+ cell count. CONCLUSION: The means by which the HLA score profile influences the time to AIDS is probably through immunologic responses that affect the rate of HIV-1 replication, as manifested by the HIV-1 RNA plasma viral load during the first 6-12 months following acute infection.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/virología , Linfocitos T CD4-Positivos/inmunología , VIH-1 , Antígenos HLA/inmunología , Enfermedad Aguda , Adulto , Biomarcadores , Recuento de Linfocito CD4 , Estudios de Cohortes , Progresión de la Enfermedad , Estudios de Seguimiento , Seropositividad para VIH , VIH-1/inmunología , Humanos , Modelos Lineales , Masculino , Modelos de Riesgos Proporcionales , ARN Viral , Carga Viral
12.
Cancer Epidemiol Biomarkers Prev ; 10(10): 1037-45, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11588129

RESUMEN

To examine Senegalese women to confirm and extend associations between HLA class II types and cervical cancer previously observed among African-American, Caucasian, Hispanic, and Japanese ethnic populations, 55 Senegalese women with invasive cervical carcinoma were compared with age-matched (human papillomavirus) HPV-positive (n = 83) and HPV-negative (n = 107) control women. PCR-based HPV and HLA typing methods were used. Data were analyzed using a global randomization test and conditional logistic regression. Although this study failed to confirm a previously reported association between cervical cancer and DQB1*03 alleles, the DRB1*1101-DQB1*0301 haplotype was detected more frequently among cervical carcinoma cases than among controls (adjusted odds ratio, 2.6; 95% confidence interval, 1.0-7.1). Furthermore, as reported by others, we observed a negative association of borderline statistical significance between DRB1*13 and cervical carcinoma (adjusted odds ratio, 0.5; 95% confidence interval, 0.2-1.1). Observations from this study confirm earlier findings of a negative association between DRB1*13 and cervical cancer and suggest that specific DRB1-DQB1 haplotype combinations, rather than individual DQB1*03 alleles, increase the risk for cervical cancer.


Asunto(s)
Genes MHC Clase II/genética , Predisposición Genética a la Enfermedad/epidemiología , Antígenos HLA-DQ/genética , Antígeno HLA-DR2/genética , Neoplasias del Cuello Uterino/genética , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Estudios de Cohortes , Intervalos de Confianza , Femenino , Marcadores Genéticos/genética , Humanos , Incidencia , Modelos Logísticos , Persona de Mediana Edad , Oportunidad Relativa , Valores de Referencia , Medición de Riesgo , Muestreo , Senegal/epidemiología , Neoplasias del Cuello Uterino/epidemiología , Neoplasias del Cuello Uterino/patología
13.
J Immunol Methods ; 87(1): 21-7, 1986 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-2419448

RESUMEN

The measurement of the mouse antibody response to cationized bovine serum albumin (cat BSA) and bovine gammaglobulin (cat BGG) was complicated because of the unique properties of these antigens. Cat BGG non-specifically bound rabbit anti-mouse gammaglobulin conjugated to alkaline phosphatase. This was minimized by adding the polyanion, heparin. Cat BSA also reacted non-specifically with some conjugates, but the reaction with specific antibody was enhanced by the addition of the polyanions heparin or dextran sulfate. The non-specific reaction did not appear to be related to the concentration of antigen used to coat the plastic plates. In addition, in ELISA inhibition experiments high concentration of antigens (greater than 100 micrograms/ml) seemed to result in non-specific inhibition of the antibody antigen reaction. A proposed model to explain the problems is based on the polycationic surface formed by coating the plates with the cationized proteins. This cationic surface can be neutralized by polyanions, reducing the non-specific and enhancing the specific reactions. It appears that other polycationic molecules might share these unique properties and these factors must be considered when they are measured.


Asunto(s)
Antígenos de Superficie/análisis , Inmunoglobulina G/inmunología , Albúmina Sérica Bovina/inmunología , Fosfatasa Alcalina , Animales , Formación de Anticuerpos , Especificidad de Anticuerpos , Reacciones Antígeno-Anticuerpo , Cationes/inmunología , Bovinos , Ensayo de Inmunoadsorción Enzimática , Epítopos , Ratones , Ratones Endogámicos
14.
Science ; 258(5081): 490-1, 1992 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-17833143
15.
Anticancer Res ; 19(1B): 661-5, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10216473

RESUMEN

BACKGROUND: Nasopharyngeal carcinoma (NPC) has a striking geographic/ethnic distribution, with especially high rates among southern Chinese. Previous studies have indicated that a family history of NPC is associated with increased risk and noted familial clustering in low-risk populations. MATERIALS AND METHODS: We investigated differences between sporadic and familial cases of NPC in a case-control study of 375 histologically confirmed NPC cases (99% response rate) and 328 age-, sex-, and geographically-matched controls (88% response rate). All participants answered a detailed risk factor interview and donated blood for EBV and CYP 2E1 testing. RESULTS: Subjects with a first degree relative with NPC had on odds ratio (OR) of 7.6 (95% confidence interval (CI) = 2.3-25), while those with a family history of any other cancer had only a slightly elevated risk of disease (OR = 1.4; 95% CI = .93-2.2). Of the cases, 25 (6.7%) were familial--having at least one first degree relative with NPC. No significant difference was seen between familial and sporadic cases with respect to sex, age, ethnicity, histology or stage. There was a nonsignificant (p = 0.16) increase in T1N2 tumors among familial cases, suggesting a more aggressive tumor. Family history of other cancers, EBV serologies, or the distribution of the RsaI c2 form of the allele of cytochrome P450 2E1 were also not significantly different between the two groups. CONCLUSIONS: In conclusion, while genetic factors are likely to play an important role in NPC pathogenesis, our results provide little evidence that a familial form of NPC exists with characteristics notably distinct from sporadic cases.


Asunto(s)
Neoplasias Nasofaríngeas/epidemiología , Neoplasias Nasofaríngeas/genética , Adulto , Factores de Edad , Biomarcadores/sangre , Estudios de Casos y Controles , Demografía , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/sangre , Neoplasias/epidemiología , Neoplasias/genética , Factores de Riesgo , Factores Sexuales , Taiwán
16.
Talanta ; 13(1): 43-8, 1966 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18959845

RESUMEN

A spectrophotometric method is described for the determination of trace quantities of lithium in beryllium metal and its oxide. Lithium is selectively separated from beryllium by extraction from 1M potassium hydroxide solution into 0.1M dipivaloylmethane in diethyl ether. Fluoride, added before the extraction, successfully masks the beryllium; as little as 3 microg of lithium can be separated from as much as 1 g of beryllium. The lithium is then back-extracted into 0.1M hydrochloric acid and is determined spectrophotometrically with o-(2-hydroxy-3,6-disulpho-1-naphthylazo) benzene arsonic acid, Thoron. In an acetone-water medium Beer's law is obeyed over the range 0.1-1.0 microg ml. The method has been applied successfully to the determination of lithium in concentrations as low as 3 ppm; the relative standard deviation for the determination of 200 ppm is 3%.

17.
Avian Dis ; 35(2): 422-5, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1649595

RESUMEN

A commercial broiler farm with a history of poor feed conversion and chronic feed-passage problems was chosen for investigation. Chickens were taken from the broiler flock at specified intervals during growout and tested by virus isolation and enzyme-linked immunosorbent assay (ELISA) for avian reovirus. Abnormal tissue pathology was first seen in the broilers at 9 days of age and continued sporadically throughout the growout period. Antireovirus antibody levels began to increase at 24 days of age. Avian reovirus and avian adenovirus was recovered at different intervals starting at 17 and 31 days of age, respectively. One-day-old specific-pathogen-free chicks housed in filtered-air positive-pressure isolation units were inoculated with two inocula recovered from the field study. Avian reovirus was recovered from the tissues of both treatment groups using chick kidney cells. Significant weight differences were seen in one of the two treatment groups. This avian reovirus was given the name SS-412.


Asunto(s)
Pollos , Enfermedades Gastrointestinales/veterinaria , Enfermedades de las Aves de Corral/microbiología , Infecciones por Reoviridae/veterinaria , Reoviridae/aislamiento & purificación , Animales , Anticuerpos Antivirales/sangre , Arkansas , Aviadenovirus/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Enfermedades Gastrointestinales/microbiología , Reoviridae/inmunología , Infecciones por Reoviridae/microbiología , Organismos Libres de Patógenos Específicos
18.
J Hum Lact ; 10(1): 31-7, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7619244

RESUMEN

In barely more than half a century, between the 1880s and the 1940s, infant feeding practices changed dramatically in the United States. In the nineteenth century, breastfeeding predominated, though alternatives were used in some cases. By the mid-twentieth century, the consensus of health care personnel and the general public supported medically-directed artificial infant feeding. A similar trend was apparent in New Zealand as well, although there the popularity of bottle-feeding occurred somewhat later and replaced breastfeeding more rapidly. Although the timing and pace of the shift from breastfeeding to bottle-feeding differed slightly for women in these geographically disparate parts of the world, the factors that influenced women's choices were similar (most particularly the medicalization of infant feeding and the institutionalization of childbirth), and the outcomes the same: women bottle-fed their infants.


Asunto(s)
Alimentación con Biberón/historia , Lactancia Materna , Comparación Transcultural , Femenino , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Cuidado del Lactante/historia , Alimentos Infantiles/historia , Recién Nacido , Nueva Zelanda , Estados Unidos
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