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1.
Pediatr Infect Dis J ; 20(11): 1090-2, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11734720

RESUMO

Women enrolled in prenatal care at Grady Health System, Atlanta, GA, have routinely been offered HIV counseling and voluntary testing since 1987. Consistently >90% have accepted testing. With implementation of US Public Health Service guidelines for perinatal zidovudine prophylaxis in 1994, the mother-to-child HIV transmission rate rapidly decreased from 18% to 8% during the subsequent 2 years.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/transmissão , HIV/isolamento & purificação , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Zidovudina/uso terapêutico , Tomada de Decisões , Feminino , Infecções por HIV/prevenção & controle , Humanos , Recém-Nascido , Modelos Logísticos , Programas de Rastreamento , Gravidez , Cuidado Pré-Natal , Fatores de Risco
2.
J Acquir Immune Defic Syndr ; 28(1): 65-72, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11579279

RESUMO

OBJECTIVES: To evaluate implementation of 1994 United States Public Health Service guidelines for zidovudine (ZDV) use in HIV-infected women and their newborns by describing the prevalence of use of perinatal ZDV and other antiretrovirals and by investigating determinants of not receiving perinatal ZDV. DESIGN/METHODS: The Perinatal AIDS Collaborative Transmission Study is a prospective cohort study designed to collect information related to mother-to-child HIV transmission that was conducted in New York City (NY), Newark (NJ), Baltimore (MD), and Atlanta (GA), U.S.A. The current analysis was restricted to infants born between July 1994 and June 1998. RESULTS: Utilization rates for antenatal, intrapartum, and neonatal ZDV increased from 41% to 70% during the 4-year period. Use of combination antiretrovirals increased from fewer than 2% of women in 1994 to 1995 to 35% in 1997 to 1998. Antenatal and neonatal ZDV use increased each year, but intrapartum ZDV use reached a plateau after 1996. Mother-infant pairs with the following characteristics were less likely to have received a complete 3-part ZDV regimen: older maternal age, CD4 count >500 cells/microl, preterm birth, cocaine or heroin use during pregnancy, positive newborn drug screen test result, and smoking or alcohol use during pregnancy. By multivariate logistic regression adjusted for hospital and year of birth, cocaine or heroin use during pregnancy (odds ratio [OR], 2.3; 95% confidence interval [CI], 1.6-3.3), maternal CD4 count (OR, 0.4; 95% CI, 0.2-0.8; comparing <200 with >500 cells/microl), and preterm birth (OR, 1.6; 95% CI, 1.1-2.5) remained independently associated with not receiving the complete ZDV regimen. CONCLUSIONS: ZDV use by pregnant HIV-infected women and their infants has increased dramatically since publication of the 1994 guidelines. Nevertheless, women who abuse substances, give birth preterm, or have less advanced immunosuppression, were at substantial risk of not receiving the complete ZDV regimen.


Assuntos
Infecções por HIV/tratamento farmacológico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/tratamento farmacológico , Inibidores da Transcriptase Reversa/uso terapêutico , Zidovudina/uso terapêutico , Adulto , Estudos de Coortes , Feminino , Infecções por HIV/complicações , Humanos , Recém-Nascido , Período Pós-Parto , Gravidez , Cuidado Pré-Natal , Inibidores da Transcriptase Reversa/administração & dosagem , Estados Unidos , Zidovudina/administração & dosagem
3.
J Infect Dis ; 184(9): 1120-6, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11598834

RESUMO

To assess the impact of antiretroviral resistance on perinatal transmission prevention efforts, human immunodeficiency virus type 1 (HIV-1) genotypic resistance testing was done for 220 HIV-1-infected, zidovudine (AZT)-exposed pregnant women and 24 of their infected infants. The women were prospectively enrolled in 4 US cities in 1991-1997. Phylogenetic and sequencing analyses revealed 5 women with non-clade B infections traced to western African origins. AZT-associated mutations were detected in 17.3% of pregnant women, whereas genotypic resistance to nonnucleoside reverse-transcriptase inhibitors and protease inhibitors was infrequent. No significant association was detected between perinatal transmission and the presence of either AZT or nucleoside reverse-transcriptase inhibitor resistance-associated mutations. AZT resistance mutations were detected in 2 (8.3%) neonatal samples, but the mutation pattern was not identical to the mother's. Although no effect of viral resistance on mother-infant transmission was demonstrated, the advent of more-potent drug classes and the potential for the rapid emergence of resistance warrant prospective surveillance.


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral/genética , Infecções por HIV/transmissão , HIV-1/efeitos dos fármacos , Transmissão Vertical de Doenças Infecciosas , Feminino , Infecções por HIV/virologia , Protease de HIV/genética , Transcriptase Reversa do HIV/genética , HIV-1/genética , Humanos , Recém-Nascido , Dados de Sequência Molecular , Filogenia , Gravidez , Complicações Infecciosas na Gravidez/virologia , Inibidores de Proteases/farmacologia , RNA Viral/sangue , Inibidores da Transcriptase Reversa/farmacologia , Análise de Sequência de DNA
4.
J Pediatr Psychol ; 26(6): 343-52, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11490035

RESUMO

OBJECTIVE: To assess for significant differences in psychological functioning between HIV-infected children and a demographically matched healthy control group and to examine the utility of applying a stress and coping model to children with HIV disease. METHODS: Participants included HIV-infected children (ages 6-16) and their caregivers (n = 36) and a control group of healthy children and their caregivers (n = 32). During routine clinic visits, children completed measures of psychological adjustment, health locus of control, and coping style, and caregivers completed measures of their own and their child's psychological adjustment. RESULTS: Caregiver-reported and child self-reported psychological adjustment scores did not significantly differ between the HIV and control groups, with the exception of significantly more internalizing behavior problems reported in the control group. Hierarchical multiple regression analyses revealed that the stress and coping model accounted for 36% of the variance in HIV-infected children's self-reported psychological adjustment. In addition, child age and coping style were significant predictors of child self-reported psychological adjustment, but not of caregiver-reported child adjustment. CONCLUSIONS: Approximately 25% of children with HIV disease exhibited clinically significant emotional or behavioral problems; however, even higher rates of psychological adjustment problems were found in healthy children. Children with HIV disease who have not been told their diagnosis and children who endorse more emotion-focused coping strategies tend to exhibit more psychological adjustment problems.


Assuntos
Adaptação Psicológica , Infecções por HIV/congênito , Papel do Doente , Adolescente , Sintomas Afetivos/diagnóstico , Sintomas Afetivos/psicologia , Cuidadores/psicologia , Criança , Transtornos do Comportamento Infantil/diagnóstico , Transtornos do Comportamento Infantil/psicologia , Feminino , Infecções por HIV/psicologia , Humanos , Controle Interno-Externo , Masculino , Desenvolvimento da Personalidade , Fatores de Risco , Revelação da Verdade
5.
J Pediatr Psychol ; 26(6): 331-42, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11490034

RESUMO

OBJECTIVE: To assess for significant differences in psychological functioning between caregivers of HIV-infected children and caregivers of healthy children, and to examine the utility of applying a stress and coping model to caregivers of children with HIV disease. METHODS: Participants included caregivers of HIV-infected children (n = 36) and caregivers of a demographically matched control group of healthy children (n = 32). During their child's pediatric clinic visits, caregivers completed measures of psychological adjustment, stress, coping style, and family resources and support. They also completed a measure of their child's psychological adjustment. RESULTS: Caregiver psychological distress scores did not significantly differ between the HIV and control groups, and clinically significant rates of psychological distress were reported by more than a third of caregivers in both groups. Hierarchical multiple regression analyses revealed that independent of their child's illness status, stress and coping style were significant predictors of caregiver's psychological adjustment. In addition, caregiver psychological distress was a significant predictor of children's maladjustment. CONCLUSIONS: High rates of psychological distress were observed in caregivers of children with HIV disease; however, similarly high rates of psychological adjustment problems were found in caregivers of healthy children. Caregivers who reported high levels of daily stress and emotion-focused coping styles tended to report more psychological distress. Further, caregivers who reported more psychological distress also reported more internalizing and more externalizing behavior problems in their children, regardless of the child's illness status. These findings reflect the impact of poverty and environmental stress on caregivers' adjustment.


Assuntos
Adaptação Psicológica , Cuidadores/psicologia , Infecções por HIV/congênito , Estresse Psicológico/complicações , Adolescente , Criança , Transtornos do Comportamento Infantil/diagnóstico , Transtornos do Comportamento Infantil/psicologia , Feminino , Infecções por HIV/psicologia , Humanos , Controle Interno-Externo , Masculino , Determinação da Personalidade , Desenvolvimento da Personalidade , Apoio Social
6.
J Acquir Immune Defic Syndr ; 26(1): 93-102, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11176273

RESUMO

Plasma viral load from 71 HIV-1-infected neonates was measured by using Amp-RT, an ultrasensitive quantitative reverse transcriptase (RT) assay and by nucleic acid sequence-based amplification (NASBA), an RNA-based quantitative assay. Results were then compared with those obtained from detection of proviral DNA in peripheral blood mononuclear cells (PBMCs) by polymerase chain reaction (PCR) using Turnbull analysis. At 5 days of life, 50% of neonates were positive by Amp-RT, 30% were NASBA positive, and 20% were DNA-PCR positive. Through the first 12 days of life, Amp-RT was more sensitive than either NASBA or DNA-PCR in detecting HIV-1 infection. Amp-RT values correlated well with NASBA RNA values, with an overall Pearson's r = 0.63 (95% confidence interval [CI], 0.40-0.78). In proportional hazards analysis of infants aged 14 to 61 days (N = 31), a one-log increase in RNA-based viral load was associated with a > fivefold risk of disease progression when using the U.S. Centers for Disease Control and Prevention (CDC) clinical Category C (CDC-C) or death as an endpoint (p =.014). Kaplan-Meier analysis of these data found that RNA viral loads were able to predict disease progression using CDC-C/death as an endpoint (p = .013). Early quantitative viral load measurements may assist clinicians in diagnosing HIV-1 infection, stratifying risk of disease progression, and implementing a treatment plan using highly active antiretroviral therapy for infants within the first few weeks of life.


Assuntos
DNA Viral/sangue , Infecções por HIV/congênito , Infecções por HIV/diagnóstico , Transcriptase Reversa do HIV/sangue , Doenças do Recém-Nascido/diagnóstico , RNA Viral/sangue , Negro ou Afro-Americano , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Peso ao Nascer , Centers for Disease Control and Prevention, U.S. , Demografia , Progressão da Doença , Feminino , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Transcriptase Reversa do HIV/metabolismo , HIV-1/enzimologia , HIV-1/genética , HIV-1/isolamento & purificação , HIV-1/fisiologia , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/sangue , Doenças do Recém-Nascido/tratamento farmacológico , Doenças do Recém-Nascido/virologia , Recém-Nascido Prematuro , Masculino , Reação em Cadeia da Polimerase , Prognóstico , Modelos de Riscos Proporcionais , Sensibilidade e Especificidade , Taxa de Sobrevida , Estados Unidos , Carga Viral
9.
Ann N Y Acad Sci ; 918: 212-21, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11131707

RESUMO

A recent report suggesting mitochondrial dysfunction among eight HIV-exposed but uninfected children exposed perinatally to nucleoside reverse transcriptase inhibitors (NRTIs) prompted a review within the Perinatal AIDS Collaborative Transmission Study (PACTS). A standardized retrospective review was conducted of 118 deaths at < 5 years. Deaths were classified as unrelated to mitochondrial dysfunction (Class 1), unlikely related (Class 2), possibly related (Class 3), or likely related or proven (Class 4). Among 35 deaths recorded in HIV-uninfected or indeterminate children, none were classified in either Class 2, 3, or 4. We also reviewed signs or symptoms consistent with possible mitochondrial dysfunction among 1,954 living uninfected children. Only one child was in Class 3 and two siblings were in Class 2; none had perinatal antiretroviral drug exposure. We found no evidence indicating that uninfected infants exposed to perinatal NRTIs died of mitochondrial disorders or that living exposed children had symptoms of mitochondrial dysfunction.


Assuntos
Síndrome da Imunodeficiência Adquirida/prevenção & controle , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Mitocôndrias/efeitos dos fármacos , Miopatias Mitocondriais/epidemiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/transmissão , Fármacos Anti-HIV/efeitos adversos , Estudos de Coortes , Feminino , Seguimentos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Humanos , Incidência , Recém-Nascido , Mitocôndrias/patologia , Miopatias Mitocondriais/mortalidade , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Estudos Retrospectivos , Fatores de Tempo , Estados Unidos/epidemiologia
10.
J Infect Dis ; 182(1): 104-11, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10882587

RESUMO

Zidovudine (Zdv) is widely used to reduce maternal-infant human immunodeficiency virus transmission (HIV), but its consequences for disease progression among children infected despite Zdv exposure remain unknown. In a multicenter observational cohort study of 325 HIV-infected children born during 1986-1997, clinical progression was compared among infected children exposed or unexposed to Zdv during prenatal and perinatal periods. Zdv exposure was associated with 1.8-fold (95% confidence interval, 1.02-3.11) increased risk of progressing to AIDS or death after adjusting for year of birth, maternal CD4 cell count, maternal AIDS diagnosis, and subsequent antiretroviral therapy of the child. Mean log(10) viral copies at 7-12 weeks were higher among Zdv-exposed children (P=.004). No infected child treated early with multidrug therapy progressed to AIDS or died by 1 year, regardless of early Zdv exposure. More rapid disease progression was observed among infected children exposed during pregnancy or birth to Zdv if effective multidrug therapy was not initiated.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/fisiopatologia , HIV/fisiologia , Zidovudina/uso terapêutico , Criança , Pré-Escolar , Estudos de Coortes , Progressão da Doença , HIV/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Infecções por HIV/virologia , Humanos , Transmissão Vertical de Doenças Infecciosas , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde , Assistência Perinatal , Cuidado Pré-Natal , RNA Viral/metabolismo
11.
N Engl J Med ; 342(17): 1250-3, 2000 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-10781621

RESUMO

BACKGROUND AND METHODS: Enteritis necroticans (pigbel), an often fatal illness characterized by hemorrhagic, inflammatory, or ischemic necrosis of the jejunum, occurs in developing countries but is rare in developed countries, where its occurrence is confined to adults with chronic illnesses. The causative organism of enteritis necroticans is Clostridium perfringens type C, an anaerobic gram-positive bacillus. In December 1998, enteritis necroticans developed in a 12-year-old boy with poorly controlled diabetes mellitus after he consumed pig intestines (chitterlings). He presented with hematemesis, abdominal distention, and severe diabetic ketoacidosis with hypotension. At laparotomy, extensive jejunal necrosis required bowel resection, jejunostomy, and ileostomy. Samples were obtained for histopathological examination. Polymerase-chain-reaction (PCR) assay was performed on paraffin-embedded bowel tissue with primers specific for the cpa and cpb genes, which code for the alpha and beta toxins produced by C. perfringens. RESULTS: Histologic examination of resected bowel tissue showed extensive mucosal necrosis, the formation of pseudomembrane, pneumatosis, and areas of epithelial regeneration that alternated with necrotic segments--findings consistent with a diagnosis of enteritis necroticans. Gram's staining showed large gram-positive bacilli whose features were consistent with those of clostridium species. Through PCR amplification, we detected products of the cpa and cpb genes, which indicated the presence of C. perfringens type C. Assay of ileal tissue obtained during surgery to restore the continuity of the patient's bowel was negative for C. perfringens. CONCLUSIONS: The preparation or consumption of chitterlings by diabetic patients and other chronically ill persons can result in potentially life-threatening infectious complications.


Assuntos
Clostridium perfringens , Diabetes Mellitus Tipo 1/complicações , Enterocolite Necrosante/microbiologia , Doenças Transmitidas por Alimentos , Produtos da Carne/microbiologia , Animais , Criança , Infecções por Clostridium/transmissão , Infecções por Clostridium/veterinária , Clostridium perfringens/genética , Clostridium perfringens/isolamento & purificação , Cetoacidose Diabética/etiologia , Enterocolite Necrosante/complicações , Microbiologia de Alimentos , Hematemese/etiologia , Humanos , Íleo/microbiologia , Íleo/patologia , Íleo/cirurgia , Jejuno/patologia , Jejuno/cirurgia , Masculino , Necrose , Suínos
12.
AIDS ; 14(16): 2429-36, 2000 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-11101052

RESUMO

OBJECTIVE: HIV infections in children are characterized by high viral load and, in some perinatally infected newborns, delayed appearance of viral markers. Both phenomena may be related to different levels of immune activation affecting viral replication. This study was designed to investigate the relationship between immune activation and viral replication in pediatric HIV infection, and the role of pre-existent immune activation in facilitating HIV transmission to the fetus/newborn. DESIGN: Plasma levels of soluble L-selectin (s-LS), an immune activation marker, were determined in 100 infants with perinatally transmitted HIV infection, compared with 106 age-matched HIV-exposed uninfected controls. Included in the analysis were samples from 31 HIV-infected (10 PCR+ and 21 PCR-) and 35 uninfected newborns aged < 2 days. METHODS: To determine s-LS levels, a solid phase ELISA was performed on plasma samples of patients and controls. RESULTS: s-LS levels in uninfected children were higher than those in normal adults. HIV-infected patients had more rapidly increasing values in the first 6 months of life compared with uninfected infants. Plasma s-LS levels correlated with HIV viral loads (r, 0.50). Among newborns in the first 2 days of life, s-LS levels were lowest in those with negative PCR tests, compared with PCR-positive or uninfected infants. CONCLUSIONS: These results suggest that higher immune activation in children contributes to higher viral loads, and that the level of pre-existent immune activation may have a role in determining which infants have detectable virus in peripheral blood at birth.


Assuntos
Infecções por HIV/imunologia , HIV-1/fisiologia , Selectina L/sangue , Carga Viral , Pré-Escolar , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Humanos , Lactente , Recém-Nascido , RNA Viral/sangue
13.
J AOAC Int ; 82(2): 251-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10191531

RESUMO

Four laboratories participated in a mini-collaborative study of AOAC Official Method 971.22, Standards for Aflatoxins, Thin-Layer Chromatographic Method, to extend the method to 3 replacement solvents for benzene for calibration of standard aflatoxin solutions. Triplicate test sample vials, each containing 25 micrograms of the respective aflatoxin for each of the 4 aflatoxins and for each of the solvents, were prepared and sent to each collaborator. The collaborators dissolved the aflatoxin in each vial in 2 mL solvent, measured the UV spectrum, and reported the absorptivity maxima near 350 nm. The concentrations of the aflatoxins in the test samples were determined by dissolving identical test samples in benzene-acetonitrile (98 + 2) and following the procedure described in AOAC Official Method 971.22. These concentrations were, in turn, used to determine the molar absorptivities in the other 3 solvents (see Table 1). AOAC Official Method 971.22 has been modified to extend its applicability to 3 replacement solvents for benzene for calibration of standard aflatoxin solutions.


Assuntos
Acetonitrilas , Aflatoxinas/química , Metanol , Solventes , Espectrofotometria Ultravioleta , Tolueno , Absorção , Aflatoxina B1/análise , Aflatoxina B1/química , Aflatoxinas/análise , Benzeno , Padrões de Referência , Soluções
14.
J Infect Dis ; 179(1): 52-8, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9841822

RESUMO

Predictors and prognosis of intrauterine and intrapartum human immunodeficiency virus (HIV) transmission were investigated among 432 children of HIV-infected women in the Perinatal AIDS Collaborative Transmission Study. Timing of transmission was inferred from polymerase chain reaction or viral culture within 2 days of birth. Proportions of infections due to intrauterine transmission were similar among women using (29%) or not using zidovudine (30%). Preterm delivery was strongly associated with intrapartum transmission (relative risk, 3.7; 95% confidence interval [CI], 2.2-6.1), particularly among infants delivered longer after membrane rupture, but was not associated with intrauterine transmission. Progression to AIDS or death increased 2.5-fold (95% CI, 1.1-5.8) among intrauterine infected children, adjusting for preterm delivery, and maternal CD4 cell count. Early transmission appears unlikely to explain instances of zidovudine failure. Preterm infants may be more vulnerable to HIV acquisition at delivery, especially if membrane rupture is prolonged. Intrauterine infection does not appear to increase risk of preterm delivery.


Assuntos
Infecções por HIV/complicações , Infecções por HIV/transmissão , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/virologia , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Feminino , Idade Gestacional , Infecções por HIV/tratamento farmacológico , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/imunologia , Prognóstico , Fatores de Risco , Fatores de Tempo , Zidovudina/uso terapêutico
15.
J Infect Dis ; 178(3): 680-5, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9728535

RESUMO

The effect of human immunodeficiency virus (HIV)-induced thymic dysfunction (TD) on mortality was studied in 265 infected infants in the CDC Perinatal AIDS Collaborative Transmission Study. TD was defined as both CD4 and CD8 T cell counts below the 5th percentile of joint distribution for uninfected infants within 6 months of life. The 40 HIV-infected infants with TD (15%) had a significantly greater mortality than did the 225 children without TD (44% vs. 9% within 2 years). Infants with TD infected in utero had higher mortality than did those infected intrapartum (70% vs. 37% within 2 years), while no significant difference was noted between infants without TD with either mode of transmission. The TD profile was independent of plasma virus load. Virus-induced TD by particular HIV strains and the time of transmission are likely to explain the variation in pathogenesis and patterns of disease progression and suggest the need for early aggressive therapies for HIV-infected infants with TD.


Assuntos
Infecções por HIV/mortalidade , Infecções por HIV/fisiopatologia , HIV-1 , Timo/fisiopatologia , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Estudos de Coortes , Infecções por HIV/virologia , HIV-1/genética , Humanos , Recém-Nascido , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Tempo
16.
Poult Sci ; 77(6): 812-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9628528

RESUMO

Broiler breeder hens were fed diets amended with 0 and 10 mg/kg (Trial 1) or 0, 0.2, 1, or 5 mg/kg (Trial 2) of aflatoxin (AF). Fertile eggs collected during 14 d of AF feeding were examined for AF residues. Various immunological endpoints were examined in chicks hatched from these eggs. Eggs collected at 7 d of AF feeding (Trial 1) had 0.15 to 0.48 ng/g of AFB1 and 0.22 to 0.51 ng/g of aflatoxicol, whereas eggs collected at 14 d of AF feeding had 0.05 to 0.60 ng of AFB1/g and 0.19 to 1.20 ng of aflatoxicol/g. In both trials, AF dietary exposure resulted in embryonic mortality and reduction in hatchability compared to controls. The AF progeny chicks in Trial 2 had total anti-SRBC antibodies similar to the controls during the primary antibody response. However, at 5 and 7 d after secondary SRBC injection, the antibody levels in the 1 and 5 mg/kg AF groups were lower than those of controls. Depression in anti-Brucella abortus antibodies occurred only in chicks from the 5 mg/kg AF group. Furthermore, phagocytosis of SRBC and reactive oxygen intermediate production by macrophages from AF progeny chicks were reduced as compared with the control chicks. The findings of this study imply that the progeny chicks from hens consuming a AF-amended diet may be increasingly susceptible to disease owing to suppression of humoral and cellular immunity.


Assuntos
Aflatoxinas/farmacologia , Ração Animal , Galinhas/imunologia , Aflatoxina B1/farmacocinética , Aflatoxina B1/farmacologia , Aflatoxinas/administração & dosagem , Aflatoxinas/farmacocinética , Análise de Variância , Animais , Formação de Anticorpos/efeitos dos fármacos , Aspergillus , Brucella abortus/imunologia , Carcinógenos/farmacocinética , Carcinógenos/farmacologia , Embrião de Galinha , Feminino , Fertilidade , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Oviposição , Fagocitose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
17.
AIDS ; 12(3): 301-8, 1998 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-9517993

RESUMO

OBJECTIVES: To evaluate the impact of perinatal zidovudine use on the risk of perinatal transmission of HIV and to determine risk factors for transmission among women using perinatal zidovudine. DESIGN: Prospective cohort study of 1533 children born to HIV-infected women between 1985 and 1995 in four US cities. METHODS: The association of potential risk factors with perinatal HIV transmission was assessed with univariate and multivariate statistics. RESULTS: The overall transmission risk was 18% [95% confidence interval (CI), 16-21]. Factors associated with transmission included membrane rupture > 4 h before delivery [relative risk (RR), 2.1; 95% CI, 1.6-2.7], gestational age < 37 weeks (RR, 1.8; 95% CI, 1.4-2.2), maternal CD4+ lymphocyte count < 500 x 10(6) cells/l (RR, 1.7; 95% CI, 1.3-2.2), birthweight < 2500 g (RR, 1.7; 95% CI, 1.3-2.1), and antenatal and neonatal zidovudine use (RR, 0.6; 95% CI, 0.4-0.9). For infants exposed to zidovudine antenatally and neonatally, the transmission risk was 13% overall but was significantly lower following shorter duration of membrane rupture (7%) and term delivery (9%). The transmission risk declined from 22% before 1992 to 11% in 1995 (P < 0.001) in association with increasing zidovudine use and changes in other risk factors. CONCLUSIONS: Perinatal HIV transmission risk has declined with increasing perinatal zidovudine use and changes in other factors. Further reduction in transmission for women taking zidovudine may be possible by reducing the incidence of other potentially modifiable risk factors, such as long duration of membrane rupture and prematurity.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/prevenção & controle , Infecções por HIV/transmissão , HIV-1 , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Zidovudina/administração & dosagem , Adulto , Feminino , Infecções por HIV/congênito , Infecções por HIV/epidemiologia , Humanos , Recém-Nascido , Troca Materno-Fetal , Gravidez , Prevalência , Risco , Fatores de Risco
18.
J Infect Dis ; 175(6): 1333-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9180171

RESUMO

Results of polymerase chain reaction (PCR) and p24 antigen detection after immune complex dissociation (p24-ICD) were compared with antibody results after 18 months of age for human immunodeficiency virus (HIV) diagnosis in 345 prospectively followed, perinatally exposed infants. Of 59 infected and 286 uninfected infants tested at 1-6 months of age, sensitivity and specificity were, respectively, 100% and > 97% for PCR and 90% and > 97% for p24-ICD. Testing was done on > or = 2 occasions in the first 6 months of life in 43 infected infants; 77% had > or = 2 positive results with the same test. Of these infants, 68% had 2 positive p24-ICD tests. In uninfected infants, 96% had only negative tests; none had > 1 positive. By 6 months, all uninfected infants with > or = 2 PCR results could have been diagnosed. HIV status can be determined by PCR by age 6 months in most HIV-exposed infants. p24-ICD should not be used alone, because of its lower sensitivity, but may be useful in areas without advanced laboratory support.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Infecções por HIV/diagnóstico , Reação em Cadeia da Polimerase/métodos , Complexo Antígeno-Anticorpo/sangue , DNA Viral/sangue , Georgia , Anticorpos Anti-HIV/sangue , Proteína do Núcleo p24 do HIV/sangue , Infecções por HIV/transmissão , Hospitais Comunitários , Humanos , Lactente , Recém-Nascido , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade
19.
Clin Perinatol ; 24(1): 161-80, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9099508

RESUMO

Along with increasing knowledge of factors that put infants at risk for mother-to-infant HIV transmission (e.g., maternal-viral load, HIV-disease state, prematurity, and prolonged membrane rupture), there are new approaches to reducing the likelihood of such transmission (e.g., zidovudine treatment). Additional means of reducing transmission may become available in years to come. In this context, prenatal voluntary identification of HIV-infected women is vital. Finally, appropriate use of early diagnostic tests in HIV-exposed infants will allow effective use of prophylactic and therapeutic means.


Assuntos
Infecções por HIV , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , Sorodiagnóstico da AIDS , Fármacos Anti-HIV/uso terapêutico , Parto Obstétrico , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/transmissão , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/tratamento farmacológico , Cuidado Pré-Natal
20.
N Engl J Med ; 335(19): 1431-6, 1996 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-8875920

RESUMO

BACKGROUND: Infants with congenital thymic deficiency (the DiGeorge syndrome) have immunodeficiency and a characteristic pattern of low CD4+ and CD8+ T-lymphocyte counts and low CD5+ B-lymphocyte counts. Because the thymus is essential for the generation of CD4+ cells, we sought evidence of thymus dysfunction in infants infected perinatally with the human immunodeficiency virus (HIV). METHODS: We studied the immunophenotypes of 59 infants with maternally transmitted HIV, 5 infants with the DiGeorge syndrome, and 168 infants exposed to HIV but not infected. The criteria for a presumed thymic defect were reductions in both the CD4+ and CD8+ T-cell subgroups during the first six months of life that were confirmed in a subgroup of infants by low counts of CD4+CD45RA+ and CD4+CD45RO+ T cells and CD5+ B cells. RESULTS: Of the 59 HIV-infected infants, 17 had immunophenotypes similar to those of infants with the DiGeorge syndrome. The risks of the acquired immunodeficiency syndrome (AIDS) by the ages of 12 and 24 months were 75 percent and 92 percent in these 17 infants, as compared with 14 and 34 percent in the other 42 infants (P<0.001). Nine of the HIV-infected infants with the DiGeorge-like immunophenotype (53 percent) died within six months of the progression to AIDS, as compared with only three of the other infants (7 percent, P=0.006). CONCLUSIONS: In some infants infected perinatally with HIV, a pattern of lymphocyte depletion develops that resembles the pattern in congenital thymic deficiency. Since HIV disease progresses rapidly in such infants, they may be candidates for early antiviral therapy and attempts at immune reconstitution.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome de DiGeorge/imunologia , Infecções por HIV/imunologia , Timo/imunologia , Síndrome da Imunodeficiência Adquirida/mortalidade , Progressão da Doença , Feminino , Infecções por HIV/transmissão , Humanos , Imunofenotipagem , Lactente , Transmissão Vertical de Doenças Infecciosas , Contagem de Linfócitos , Masculino , Estudos Prospectivos , Timo/fisiopatologia
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