RESUMO
AIM: To compare chest radiography (CXR) findings in human immunodeficiency virus (HIV)-positive and HIV-negative children who had microbiologically confirmed pulmonary tuberculosis (PTB). MATERIALS AND METHODS: Retrospective analysis of CXRs from children with known HIV status and microbiologically confirmed PTB (culture or GeneXpert Xpert MTB/RIF positive), who were hospitalised or seen at a primary healthcare centre over a 5-year period. Radiological findings were compared according to HIV and nutritional status. RESULTS: CXRs of 130 children were analysed from 35 (27%) HIV- positive and 95 (73%) HIV-negative children with confirmed PTB, median age 45.7 months (interquartile range [IQR] 18-81.3 months). CXR changes consistent with PTB were reported in 21/35 (60%) of HIV-positive and 59/95 (62%) of HIV-negative patients, (p=0.81). Normal CXR was identified in 3/35 (8.6%) of HIV-positive and 5/95 (5.3%) of HIV-negative patients (p=0.81). Airway compression was present in 3/35 (8.6%) of HIV-positive and 7/95 (7.4%) of HIV-negative patients (p>0.99). Overall, lymphadenopathy was identified in 42/130 (32.3%) of patients, 11/35 (31.4 %) were HIV-positive compared with 31/95 (32.6%) HIV-negative patients. Airspace consolidation was present in 60% of both HIV-positive (21/35) and HIV-negative patients (57/95). Pleural effusion was present in 2/35 (5.7 %) of HIV-negative and 9/95 (9.5 %) of HIV-negative patients. There were no statistically significant radiological differences by HIV group. CONCLUSION: There were no significant differences in the CXR findings between the HIV-positive and HIV-negative children with confirmed PTB.
Assuntos
Infecções por HIV , Tuberculose Pulmonar , Criança , Humanos , Lactente , Pré-Escolar , Estudos Retrospectivos , Escarro , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/diagnóstico por imagem , Infecções por HIV/complicações , Infecções por HIV/diagnóstico por imagem , HIVRESUMO
IgE antibodies (Ab) specific to galactose-α-1,3-galactose (alpha-gal) are responsible for a delayed form of anaphylaxis that occurs 3-6 hours after red meat ingestion. In a unique prospective study of seventy participants referred with a diagnosis of idiopathic anaphylaxis (IA), six (9%) were found to have IgE to alpha-gal. Upon institution of a diet free of red meat, all patients had no further episodes of anaphylaxis. Two of these individuals had indolent systemic mastocytosis (ISM). Those with ISM had more severe clinical reactions but lower specific IgE to alpha-gal and higher serum tryptase levels, reflective of the mast cell burden. The identification of alpha-gal syndrome in patients with IA supports the need for routine screening for this sensitivity as a cause of anaphylaxis, where reactions to alpha-gal are delayed and thus may be overlooked.
Assuntos
Anafilaxia/etiologia , Anafilaxia/imunologia , Hipersensibilidade Alimentar/imunologia , Galactose/imunologia , Carne Vermelha/efeitos adversos , Adulto , Idoso , Anafilaxia/complicações , Animais , Hipersensibilidade Alimentar/complicações , Humanos , Hipersensibilidade Tardia/etiologia , Hipersensibilidade Tardia/imunologia , Imunoglobulina E/imunologia , Masculino , Mastocitose Sistêmica/complicações , Mastocitose Sistêmica/imunologia , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Artemether-lumefantrine is currently the most widely recommended treatment of uncomplicated malaria. Lopinavir-based antiretroviral therapy is the commonly recommended second-line HIV treatment. Artemether and lumefantrine are metabolised by cytochrome P450 isoenzyme CYP3A4, which lopinavir/ritonavir inhibits, potentially causing clinically important drug-drug interactions. METHODS: An adaptive, parallel-design safety and pharmacokinetic study was conducted in HIV-infected (malaria-negative) patients: antiretroviral-naïve and those stable on lopinavir/ritonavir-based antiretrovirals. Both groups received the recommended six-dose artemether-lumefantrine treatment. The primary outcome was day-7 lumefantrine concentrations, as these correlate with antimalarial efficacy. Adverse events were solicited throughout the study, recording the onset, duration, severity, and relationship to artemether-lumefantrine. RESULTS: We enrolled 34 patients. Median day-7 lumefantrine concentrations were almost 10-fold higher in the lopinavir than the antiretroviral-naïve group [3170 versus 336 ng/mL; p = 0.0001], with AUC(0-inf) and Cmax increased five-fold [2478 versus 445 µg.h/mL; p = 0.0001], and three-fold [28.2 versus 8.8 µg/mL; p < 0.0001], respectively. Lumefantrine Cmax, and AUC(0-inf) increased significantly with mg/kg dose in the lopinavir, but not the antiretroviral-naïve group. While artemether exposure was similar between groups, Cmax and AUC(0-8h) of its active metabolite dihydroartemisinin were initially two-fold higher in the lopinavir group [p = 0.004 and p = 0.0013, respectively]. However, this difference was no longer apparent after the last artemether-lumefantrine dose. Within 21 days of starting artemether-lumefantrine there were similar numbers of treatment emergent adverse events (42 vs. 35) and adverse reactions (12 vs. 15, p = 0.21) in the lopinavir and antiretroviral-naïve groups, respectively. There were no serious adverse events and no difference in electrocardiographic QTcF- and PR-intervals, at the predicted lumefantrine Tmax. CONCLUSION: Despite substantially higher lumefantrine exposure, intensive monitoring in our relatively small study raised no safety concerns in HIV-infected patients stable on lopinavir-based antiretroviral therapy given the recommended artemether-lumefantrine dosage. Increased day-7 lumefantrine concentrations have been shown previously to reduce the risk of malaria treatment failure, but further evidence in adult patients co-infected with malaria and HIV is needed to assess the artemether-lumefantrine risk : benefit profile in this vulnerable population fully. Our antiretroviral-naïve patients confirmed previous findings that lumefantrine absorption is almost saturated at currently recommended doses, but this dose-limited absorption was overcome in the lopinavir group. TRIAL REGISTRATION: Clinical Trial Registration number NCT00869700. Registered on clinicaltrials.gov 25 March 2009.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/farmacocinética , Artemeter , Artemisininas/efeitos adversos , Artemisininas/farmacocinética , Artemisininas/uso terapêutico , Interações Medicamentosas , Etanolaminas/efeitos adversos , Etanolaminas/farmacocinética , Etanolaminas/uso terapêutico , Feminino , Fluorenos/efeitos adversos , Fluorenos/farmacocinética , Fluorenos/uso terapêutico , Infecções por HIV/metabolismo , HIV-1/efeitos dos fármacos , Humanos , Lopinavir/efeitos adversos , Lopinavir/farmacocinética , Lopinavir/uso terapêutico , Lumefantrina , Masculino , Ritonavir/efeitos adversos , Ritonavir/farmacocinética , Ritonavir/uso terapêuticoRESUMO
BACKGROUND: The association between atopy and asthma is attenuated in non-affluent populations, an effect that may be explained by childhood infections such as geohelminths. OBJECTIVE: To investigate the association between atopy and wheeze in schoolchildren living in urban and rural areas of Ecuador and examine the effects of geohelminths on this association. METHODS: We performed nested case-control studies among comparable populations of schoolchildren living in rural communities and urban neighbourhoods in the Province of Esmeraldas, Ecuador. We detected geohelminths in stool samples, measured recent wheeze and environmental exposures by parental questionnaire, and atopy by specific IgE (sIgE) and skin prick test (SPT) reactivity to aeroallergens. RESULTS: Atopy, particularly sIgE to house dust mite (HDM), was more strongly associated with recent wheeze in urban than rural schoolchildren: (urban, adj. OR 5.19, 95% CI 3.37-8.00, P < 0.0001; rural, adj. OR 1.81, 95%CI 1.09-2.99, P = 0.02; interaction, P < 0.001). The population fractions of wheeze attributable to atopy were approximately two-fold greater in urban schoolchildren: SPT to any allergen (urban 23.5% vs. rural 10.1%), SPT to HDM (urban 18.5% vs. rural 9.6%), and anti-HDM IgE (urban 26.5% vs. rural 10.5%), while anti-Ascaris IgE was related to wheeze in a high proportion of rural (49.7%) and urban (35.4%) children. The association between atopy and recent wheeze was attenuated by markers of geohelminth infections. CONCLUSIONS: Our data suggest that urban residence modifies the association between HDM atopy and recent wheeze, and this effect is explained partly by geohelminth infections.
Assuntos
Hipersensibilidade Imediata/epidemiologia , Hipersensibilidade Imediata/imunologia , Sons Respiratórios/imunologia , População Rural , População Urbana , Adolescente , Alérgenos/imunologia , Animais , Estudos de Casos e Controles , Criança , Estudos Transversais , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , América Latina/epidemiologia , Masculino , Fatores de Risco , Testes Cutâneos , Inquéritos e Questionários , Adulto JovemRESUMO
BACKGROUND: Only limited evidence is available regarding the cytokine repertoire of effector T cells associated with peanut allergy, and how these responses relate to IgE antibodies to peanut components. OBJECTIVE: To interrogate T cell effector cytokine populations induced by Ara h 1 and Ara h 2 among peanut allergic (PA) children in the context of IgE and to evaluate their modulation during oral immunotherapy (OIT). METHODS: Peanut-reactive effector T cells were analysed in conjunction with specific IgE profiles in PA children using intracellular staining and multiplex assay. Cytokine-expressing T cell subpopulations were visualized using SPICE. RESULTS: Ara h 2 dominated the antibody response to peanut as judged by prevalence and quantity among a cohort of children with IgE to peanut. High IgE (> 15 kU(A)/L) was almost exclusively associated with dual sensitization to Ara h 1 and Ara h 2 and was age independent. Among PA children, IL-4-biased responses to both major allergens were induced, regardless of whether IgE antibodies to Ara h 1 were present. Among subjects receiving OIT in whom high IgE was maintained, Th2 reactivity to peanut components persisted despite clinical desensitization and modulation of allergen-specific immune parameters including augmented specific IgG4 antibodies, Th1 skewing and enhanced IL-10. The complexity of cytokine-positive subpopulations within peanut-reactive IL-4(+) and IFN-γ(+) T cells was similar to that observed in those who received no OIT, but was modified with extended therapy. Nonetheless, high Foxp3 expression was a distinguishing feature of peanut-reactive IL-4(+) T cells irrespective of OIT, and a correlate of their ability to secrete type 2 cytokines. CONCLUSION: Although total numbers of peanut-reactive IL-4(+) and IFN-γ(+) T cells are modulated by OIT in highly allergic children, complex T cell populations with pathogenic potential persist in the presence of recognized immune markers of successful immunotherapy.
Assuntos
Citocinas/biossíntese , Hipersensibilidade a Amendoim/imunologia , Hipersensibilidade a Amendoim/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Albuminas 2S de Plantas/imunologia , Administração Oral , Adolescente , Alérgenos/administração & dosagem , Alérgenos/imunologia , Antígenos de Plantas/administração & dosagem , Antígenos de Plantas/imunologia , Criança , Pré-Escolar , Dessensibilização Imunológica , Feminino , Glicoproteínas/imunologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunofenotipagem , Lactente , Interleucina-4/biossíntese , Masculino , Hipersensibilidade a Amendoim/terapiaRESUMO
BACKGROUND: Atopic dermatitis (AD) is common in children; however, persistence of AD with or without asthma is less common. Longitudinal studies remain limited in their ability to characterize how IgE antibody responses evolve in AD, and their relationship with asthma. OBJECTIVE: To use a cross-sectional study design of children with active AD to analyse age-related differences in IgE antibodies and relation to wheeze. METHODS: IgE antibodies to food and inhalant allergens were measured in children with active AD (5 months to 15 years of age, n = 66), with and without history of wheeze. RESULTS: Whereas IgE antibodies to foods persisted at a similar prevalence and titre throughout childhood, IgE antibodies to all aeroallergens rose sharply into adolescence. From birth, the chance of sensitization for any aeroallergen increased for each 12-month increment in age (OR ≥ 1.21, P < 0.01), with the largest effect observed for dust mite (OR = 1.56, P < 0.001). A steeper age-related rise in IgE antibody titre to dust mite, but no other allergen was associated with more severe disease. Despite this, sensitization to cat was more strongly associated with wheeze (OR = 4.5, P < 0.01), and linked to Fel d 1 and Fel d 4, but not Fel d 2. Comparison of cat allergic children with AD to those without, revealed higher IgE levels to Fel d 2 and Fel d 4 (P < 0.05), but not Fel d 1. CONCLUSIONS AND CLINICAL RELEVANCE: Differences in sensitization to cat and dust mite among young children with AD may aid in identifying those at increased risk for disease progression and development of asthma. Early sensitization to cat and risk for wheeze among children with AD may be linked to an increased risk for sensitization to a broader spectrum of allergen components from early life. Collectively, our findings argue for early intervention strategies designed to mitigate skin inflammation in children with AD.
Assuntos
Alérgenos/imunologia , Dermatite Atópica/imunologia , Alimentos/efeitos adversos , Sons Respiratórios/imunologia , Adolescente , Fatores Etários , Animais , Especificidade de Anticorpos/imunologia , Gatos , Criança , Pré-Escolar , Estudos Transversais , Feminino , Glicoproteínas/imunologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Lactente , Lipocalinas , Masculino , Razão de Chances , PrognósticoRESUMO
BACKGROUND: Most childhood asthma in poor populations in Latin America is not associated with aeroallergen sensitization, an observation that could be explained by the attenuation of atopy by chronic helminth infections or effects of age. OBJECTIVE: To explore the effects of geohelminth infections and age on atopy, wheeze, and the association between atopy and wheeze. METHODS: A case-control study was done in 376 subjects (149 cases and 227 controls) aged 7-19 years living in rural communities in Ecuador. Wheeze cases, identified from a large cross-sectional survey, had recent wheeze and controls were a random sample of those without wheeze. Atopy was measured by the presence of allergen-specific IgE (asIgE) and skin prick test (SPT) responses to house dust mite and cockroach. Geohelminth infections were measured in stools and anti-Ascaris IgE in plasma. RESULTS: The fraction of recent wheeze attributable to anti-Ascaris IgE was 45.9%, while those for SPT and asIgE were 10.0% and 10.5% respectively. The association between atopy and wheeze was greater in adolescents than children. Although Anti-Ascaris IgE was strongly associated with wheeze (adj. OR 2.24 (95% CI 1.33-3.78, P = 0.003) and with asIgE (adj. OR 5.34, 95% CI 2.49-11.45, P < 0.001), the association with wheeze was independent of asIgE. There was some evidence that the association between atopy and wheeze was greater in uninfected subjects compared with those with active geohelminth infections. CONCLUSIONS AND CLINICAL RELEVANCE: Atopy to house dust mite and cockroach explained few wheeze cases in our study population, while the presence of anti-Ascaris IgE was an important risk factor. Our data provided only limited evidence that active geohelminth infections attenuated the association between atopy and wheeze in endemic areas or that age modified this association. The role of allergic sensitization to Ascaris in the development of wheeze, independent of atopy, requires further investigation.
Assuntos
Helmintíase/imunologia , Hipersensibilidade Imediata/etiologia , Hipersensibilidade Imediata/imunologia , Sons Respiratórios/etiologia , Sons Respiratórios/imunologia , Adolescente , Fatores Etários , Animais , Ascaris/imunologia , Estudos de Casos e Controles , Criança , Baratas/imunologia , Equador/epidemiologia , Feminino , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Masculino , Pyroglyphidae/imunologia , População Rural , Testes Cutâneos , Adulto JovemRESUMO
OBJECTIVES: This paper reports on a statistically significant association between alcohol use and deployment to the 2003 Iraq War. It assesses the occupational factors and deployment experiences associated with heavy drinking in regular UK servicemen deployed to Iraq in the first phase of the 2003 Iraq War (Operation TELIC 1, the military codename for the conflict in Iraq). METHODS: A random representative sample of 3578 regular male UK Armed Forces personnel who were deployed to Iraq during Operation TELIC 1 participated in a cross-sectional postal questionnaire study (response rate 61%). Participants completed a questionnaire, between June 2004 and March 2006 (ie, after deployment), about their health, including a measure of alcohol use (Alcohol Use Disorders Identification Test, AUDIT) and questions about their experiences on deployment to Iraq. Heavy drinkers were identified as those scoring 16 or above on the AUDIT. RESULTS: After adjustment for sociodemographic and military factors, and the presence of psychological distress, heavy drinkers were more likely to have had major problems at home during (odds ratio (OR) 1.33, 95% confidence interval (CI) 1.04 to 1.70) and following their deployment (OR 1.68, 95% CI 1.32 to 2.14). Being deployed with their parent unit (OR 1.28, 95% CI 1.02 to 1.61), medium to high in-theatre unit comradeship (medium: OR 1.35, 95% CI 1.04 to 1.77; high: OR 1.35, 95% CI 1.02 to 1.79) and poor unit leadership (OR 1.78, 95% CI 1.37 to 2.31) were also associated with heavy drinking. CONCLUSIONS: Deployment experiences and problems at home during and following deployment, as well as the occupational milieu of the unit, influence personnel's risk of heavy drinking.
Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Militares/estatística & dados numéricos , Doenças Profissionais/epidemiologia , Estudos de Coortes , Estudos Transversais , Nível de Saúde , Inquéritos Epidemiológicos , Humanos , Guerra do Iraque 2003-2011 , Masculino , Fatores de Risco , Reino Unido/epidemiologia , VeteranosRESUMO
BACKGROUND: GeneXpert MTB/RIF is useful for the diagnosis of pulmonary TB in adults, but there is limited evidence on its usefulness in extrapulmonary TB. OBJECTIVES: To investigate the diagnostic accuracy of GeneXpert MTB/RIF in HIV-infected and HIV-uninfected patients with suspected musculoskeletal TB. METHODS: A prospective study of patients with suspected musculoskeletal (bone and joint) TB was undertaken. The diagnostic accuracy of GeneXpert MTB/RIF was compared with the reference standards of culture and histopathology. RESULTS: A total of 206 biopsies from 201 patients (23% HIV-infected) were evaluated. The sensitivity and specificity of GeneXpert MTB/RIF was 92.3% (84/91) and 99.1% (114/115), respectively. GeneXpert MTB/RIF detected 8.8% more cases than culture (84/91 (92.3%) v. 76/91 (83.5%), respectively; p=0.069). GeneXpert MTB/RIF also detected all 4 multidrug-resistant TB cases and an additional 2 rifampicin-resistant cases in culture-negative samples. The sensitivity of GeneXpert MTB/RIF in HIV-infected patients was 96.9% (31/32) v. 89.6% (43/48) in HIV-uninfected patients (p=0.225). CONCLUSION: GeneXpert MTB/RIF is an accurate test for the detection of TB in tissue samples of HIV-infected and HIV-uninfected patients with suspected musculoskeletal TB. A positive GeneXpert MTB/RIF result should be regarded as microbiological confirmation of TB.
RESUMO
Sulfadoxine/pyrimethamine is recommended for intermittent preventative treatment of malaria during pregnancy. Data from 98 women during pregnancy and 77 after delivery in four African countries were analyzed using nonlinear mixed-effects modeling to characterize the effects of pregnancy, postpartum duration, and other covariates such as body weight and hematocrit on sulfadoxine/pyrimethamine pharmacokinetic properties. During pregnancy, clearance increased 3-fold for sulfadoxine but decreased by 18% for pyrimethamine. Postpartum sulfadoxine clearance decreased gradually over 13 weeks. This finding, together with hematocrit-based scaling of plasma to whole-blood concentrations and allometric scaling of pharmacokinetics parameters with body weight, enabled site-specific differences in the pharmacokinetic profiles to be reduced significantly but not eliminated. Further research is necessary to explain residual site-specific differences and elucidate whether dose-optimization, to address the 3-fold increase in clearance of sulfadoxine in pregnant women, is necessary, viable, and safe with the current fixed dose combination of sulfadoxine/pyrimethamine.
Assuntos
Antimaláricos/farmacocinética , Modelos Biológicos , Pirimetamina/farmacocinética , Sulfadoxina/farmacocinética , Adulto , África , Antimaláricos/sangue , Antimaláricos/uso terapêutico , Combinação de Medicamentos , Feminino , Humanos , Malária/prevenção & controle , Período Pós-Parto/sangue , Período Pós-Parto/metabolismo , Gravidez/sangue , Gravidez/metabolismo , Pirimetamina/sangue , Pirimetamina/uso terapêutico , Sulfadoxina/sangue , Sulfadoxina/uso terapêutico , Adulto JovemRESUMO
beta-Adrenergic receptors were demonstrated in membrane preparations from 6 human Ewing's sarcomas and compared to those from 46 other pediatric cancers with the use of the beta-adrenergic antagonist (-)-(3H)dihydroalprenolol [(-)[3H]DHA]. In contrast to the high numbers of receptor sites found in Ewing's sarcomas (55-640 fmol x mg-1 protein; dissociation constant Kd, 1-2 nM), other childhood cancers (neuroblastoma, rhabdomyosarcoma, brain tumors, lymphoma, osteosarcoma, hepatoblastoma, yolk sac, and Wilms' tumor) contained in general fewer beta-adrenergic receptor sites. Characteristics of (-)-[3H]DHA binding were therefore more fully characterized in the Ewing's tumors. Competition of (-)-[3H]DHA binding by classical catecholamine agonists, as well as by subtype selective agents metoprolol and zinterol, demonstrated the presence of a homogeneous population of beta 1-adrenergic sites in several Ewing's tumors. Adenylate cyclase activity in all Ewing's sarcomas was enhanced by GTP and NaF. However, in spite of high numbers of beta-adrenergic receptors, (-)-isoproterenol was not very effective in the activation of adenylate cyclase activity in several of the Ewing's tumors tested. Neither guanyl-5'-yl-imidophosphate nor GTP altered agonist potency for the receptor site in these catecholamine-insensitive tumors. Hill coefficients obtained from the competition experiments with (-)-isoproterenol (in the presence or absence of guanine nucleotide) were approximately 1.0. These uncoupled receptors were resistant to N-ethylmaleimide denaturation and were densensitized only 50% during culture in the presence of (-)-isoproterenol. Thus Ewing's sarcomas are relatively rich in beta-adrenergic sites, and several tumors appear to have a coupling lesion involving guanine nucleotide-dependent regulatory protein interaction with beta-adrenergic receptors and adenylate cyclase, similar in phenotype to that described in the (unc) variant of S49 mouse lymphoma.
Assuntos
Neoplasias Ósseas/metabolismo , Receptores Adrenérgicos beta/análise , Sarcoma de Ewing/metabolismo , Adenilil Ciclases/metabolismo , Antagonistas Adrenérgicos beta , Animais , Ligação Competitiva , Linhagem Celular , Criança , Di-Hidroalprenolol/farmacologia , Etanolaminas/farmacologia , Humanos , Metoprolol/farmacologia , Camundongos , Camundongos Nus , Neuroblastoma , OsteossarcomaRESUMO
The Fab fragments of several monoclonal antibodies that bind Staphylococcal nuclease have been screened for crystallization conditions. Two of these, N10 and N25, have been crystallized in forms suitable for X-ray structural analysis. The anti-Staphylococcal nuclease antibody complex N10 Fab-nuclease crystallizes with symmetry consistent with space group C2 and cell parameters of a = 234.7 A; b = 43.5 A; c = 74.4 A; beta = 106.4 degrees. A second anti-Staphylococcal nuclease antibody, N25, although crystallized starting with the Fab-nuclease complex, apparently crystallizes as uncomplexed N25 Fab with symmetry consistent with space group P3(1)21 (or its enantiomorph P3(2)21) and cell parameters of a = b = 80.9 A; c = 138.4 A.
Assuntos
Anticorpos Antibacterianos/química , Complexo Antígeno-Anticorpo/química , Fragmentos Fab das Imunoglobulinas/química , Nuclease do Micrococo/química , Anticorpos Antibacterianos/isolamento & purificação , Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Reações Antígeno-Anticorpo , Cristalização , Cristalografia por Raios X , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Nuclease do Micrococo/isolamento & purificação , Staphylococcus/enzimologia , Staphylococcus/imunologiaRESUMO
GnRH regulates the synthesis and secretion of the pituitary gonadotropins LH and FSH. One of the actions of GnRH on the gonadotropin subunit genes (alpha, LHbeta, and FSHbeta) is the regulation of transcription [messenger RNA (mRNA) synthesis]. Gonadotropin subunit transcription rates increase after gonadectomy and following exogenous GnRH pulses. However, prior studies of subunit mRNA synthesis were limited by the available methodology that did not allow simultaneous measurement of gene transcription and mature mRNA concentrations. The purpose of the current studies was to: 1) develop a reliable and sensitive method for assessing transcription rates by measuring gonadotropin subunit primary transcript RNAs (PT, RNA before intron splicing); 2) investigate the PT responses to GnRH following castration or exogenous GnRH pulses; 3) characterize the half-disappearance time for the three PT species after GnRH withdrawal; and 4) correlate changes in PT concentration with steady-state gonadotropin subunit mRNA levels measured in the same pituitary RNA samples. Using oligonucleotide primers that flanked intron-exon boundaries, quantitative RT-PCR assays for each subunit PT species were developed. These assays require only ng amounts of RNA to measure each gonadotropin subunit PT and allow us to measure both PTs and steady-state mRNAs in a single pituitary RNA sample. Primary transcript concentrations in intact male rats showed a relative abundance of alpha > LHbeta congruent with FSHbeta, similar to the relationship found previously for mRNA levels. Additionally, each PT species was only 1-2% as abundant as the corresponding mRNA. One week after castration, gonadotropin subunit PT levels were increased (alpha: 3-fold, LHbeta: 6-fold, and FSHbeta: 3-fold) in a pattern similar to subunit mRNAs. Administration of GnRH antagonist to 7-day castrate male rats resulted in a rapid decline in PT concentrations with a half-disappearance time of 2.7 h for LHbeta and 0.8 h for FSHbeta, significantly faster than earlier measurements of the half-disappearance time for mature mRNA. Finally, in a GnRH-deficient male rat model, LHbeta and FSHbeta PT concentrations increased 4- to 6-fold 5 min after a GnRH pulse and then declined toward levels seen in control animals. These data indicate that the effects of GnRH on subunit gene transcription are an important determinant of gonadotropin regulation. The appearance and disappearance of PT RNA occurs more rapidly than changes in mature mRNA. Additionally, concentrations are elevated in long term castrates, and following an exogenous GnRH pulse the transcriptional burst is rapid and brief.
Assuntos
Hormônio Foliculoestimulante/genética , Regulação da Expressão Gênica , Subunidade alfa de Hormônios Glicoproteicos/genética , Hormônio Liberador de Gonadotropina/fisiologia , Transcrição Gênica , Animais , Sequência de Bases , Éxons , Subunidade beta do Hormônio Folículoestimulante , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Íntrons , Hormônio Luteinizante/genética , Masculino , Orquiectomia , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Análise de Regressão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Transcrição Gênica/efeitos dos fármacosRESUMO
The aim of this study was to determine if the changes in gonadotropin subunit gene expression following ovariectomy reflect transcriptional and/or posttranscriptional regulation by GnRH or inhibin. Subunit transcription rates were determined by recently developed quantitative RT-PCR for subunit primary transcripts (as an indicator of gene transcription), which allow us to measure both mRNA and PT from RNA extracted from a single pituitary. Following ovariectomy, LHbeta PT concentrations increased 2- to 3-fold between 72 h and 7 d, paralleling changes in serum LH and LHbeta mRNA. In contrast, serum FSH, FSHbeta mRNA, and FSHbeta PT concentrations were 6- to 9-fold greater 12-24 h after ovariectomy followed by an additional 2.5-fold increase at 72 h. Although alpha RNA was elevated at 72 h after ovariectomy, alpha-primary transcript did not change. GnRH antagonist prevented the increase in LHbeta-PT at 72 h, but had no effect on the increase in FSHbetaPT at 12 h and was only partially effective at 72 h. The acute GnRH-independent increase in FSHbeta-primary transcript after ovariectomy could be duplicated by the administration of inhibin antiserum to intact rats; inhibin-alpha antiserum did not affect LHbeta-primary transcript, but increased FSHbeta-primary transcript concentrations 8- to 11-fold. The half-disappearance rates of LHbeta and FSHbeta primary transcripts were measured after GnRH blockade or administration of recombinant human inhibin A. The half-disappearance times for LHbeta and FSHbeta primary transcripts following GnRH blockade were 13 and 17 min, respectively; the mRNAs did not change. The effects of inhibin were specific for FSHbeta; 60 min after inhibin FSHbeta-primary transcript was undetectable with a half-disappearance time of 19 min, additionally FSHbeta mRNA levels also fell with a half-life of 94 min. In conclusion, these data support previous evidence that GnRH regulates gonadotropin gene expression primarily at the level of transcription. However, the acute increase in FSHbeta-primary transcript after ovariectomy or immunoneutralization of inhibin-alpha, and the rapid fall in FSHbeta-primary transcript following rh inhibin, provide novel evidence that inhibin suppresses FSHbeta gene transcription in addition to its action in regulating FSHbeta mRNA stability.
Assuntos
Hormônio Foliculoestimulante/genética , Hormônio Luteinizante/genética , Ovário/fisiologia , Transcrição Gênica/fisiologia , Animais , Feminino , Subunidade beta do Hormônio Folículoestimulante , Hormônio Liberador de Gonadotropina/fisiologia , Inibinas/farmacologia , Inibinas/fisiologia , Ovariectomia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes , Transcrição Gênica/efeitos dos fármacosRESUMO
Both beta 1- and beta 2-adrenergic receptors have been previously described in normal human placental homogenates; the cells upon whose surface membranes these receptors reside have not been identified. In order to show that a beta 1-adrenergic receptor is present on trophoblastic cells, the cells which mediate maternal-fetal transport and produce placental hormones, beta-adrenergic receptors were demonstrated in membrane fractions of human hydatidiform mole. Microscopic sections of the mole samples used demonstrated edematous villi lined by trophoblastic cells with minimal nontrophoblastic (stromal or vascular) contamination compared with placenta. (--)-[3H]Dihydroalprenolol [(--)-[3H]DHA] binding to molar membranes was reversible and saturable to a single class of sites (Kd = 0.97 +/- 0.12 nM; n = 7; maximum binding capacity, 72.9 +/- 6.4 fmol/mg protein). (--)-[3H]DHA binding was associated with catecholamine-stimulated adenylate cyclase activity. Agonist competition for the molar beta-adrenergic receptor showed the order of potency to be (--)isoproterenol much greater than norepinephrine = epinephrine, characteristic of a beta 1-adrenergic receptor subtype. Competition for (--)-[3H]DHA binding to trophoblastic membranes by the beta-adrenergic receptor subtype-specific agents metoprolol (beta 1 selective) and zinterol (beta 2 selective) was also characteristic of a homogeneous subtype of beta 1-adrenergic receptors. Because beta 1-adrenergic receptors alone were seen on trophoblast cells, the beta 2-adrenergic receptor in placenta must reside on nontrophoblastic elements (stromal or vascular endothelium). No differences in beta-adrenergic receptor binding were seen related with ploidy (2 or 3 N), the presence or absence of a fetus, or the progression of the mole to choriocarcinoma. Two choriocarcinoma cell lines, BeWo and JEG-3, however, showed no specific (--)-[3H]DHA binding. Human trophoblast contains beta 1-adrenergic receptors coupled to catecholamine-sensitive adenylate cyclase, supporting a role for catecholamines in the regulation of placental metabolism.
Assuntos
Mola Hidatiforme/análise , Receptores Adrenérgicos beta/análise , Receptores Adrenérgicos/análise , Trofoblastos/análise , Neoplasias Uterinas/análise , Adenilil Ciclases/metabolismo , Adolescente , Adulto , Di-Hidroalprenolol/metabolismo , Epinefrina/metabolismo , Feminino , Guanilil Imidodifosfato/metabolismo , Humanos , Isoproterenol/metabolismo , Norepinefrina/metabolismo , Gravidez , Receptores Adrenérgicos beta/metabolismoRESUMO
CONTEXT: We hypothesize that there are unrecognized value judgments that influence cytopathologists in interpreting borderline cervicovaginal smears and that these judgments contribute to the well-documented variation among cytopathologists regarding such diagnoses. OBJECTIVE: To identify and map these values. DESIGN: Survey consisting of Kodachromes and histories for 5 borderline smears. Respondents were asked to give their diagnoses, recommendations for treatment, and reasoning. RESULTS: We demonstrated a wide variation in interpretation of borderline smears similar to previous studies. We then used inductive qualitative analysis to identify the clinical reasoning and value judgments that influenced the responses. CONCLUSIONS: We mapped those diagnostic value judgments that should be used in evaluation borderline cases. We believe this map can be used to rigorously manage and standardize the use of such judgments.
Assuntos
Colo do Útero/patologia , Esfregaço Vaginal/classificação , Adulto , Carcinoma de Células Escamosas/patologia , Colposcopia , Diagnóstico Diferencial , Feminino , Humanos , Julgamento , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologiaRESUMO
Developing and evaluating educational programs in schools of nursing is one of the most critical functions of the faculty. This process can be approached from a variety of perspectives. Historically, most faculty efforts have been directed at development or evaluation; however, a more proactive approach is to incorporate a process which will encompass both. To accomplish this, two models, the Holistic Formative Evaluation Model and the Stakes Countenance Model, have been merged to produce a model which is applicable to the integrated development and evaluation of a nursing curriculum. This model, the Internal Program Development and Self-Evaluation Model, provides faculty, curriculum developers, and administrators with a comprehensive process which focuses on the monitoring program internal consistency and congruence.
Assuntos
Currículo , Educação em Enfermagem , Modelos Psicológicos , Estudos de Avaliação como Assunto , Humanos , MissouriRESUMO
Given today's technical and demanding patient care system within the hospital organization, there is a need for head nurses as nurse managers to be ever more attuned to the climate of their staff. In a study of 34 nurse managers in seven pediatric hospital organizations across a midwestern portion of the United States, an analysis of Fiedler's Leader Match Scales showed the significance of group climate on retention.
Assuntos
Processos Grupais , Serviço Hospitalar de Enfermagem/organização & administração , Supervisão de Enfermagem/organização & administração , Cultura Organizacional , Enfermagem Pediátrica , Seleção de Pessoal/métodos , Adulto , Feminino , Hospitais Pediátricos , Humanos , Liderança , Masculino , Pessoa de Meia-Idade , Motivação , Pesquisa em Administração de Enfermagem , Supervisão de Enfermagem/normas , Teoria Psicológica , Estados Unidos , Recursos HumanosRESUMO
BACKGROUND: Induced sputum (IS) is increasingly used to provide specimens for microbiological confirmation of Mycobacterium tuberculosis. The aim of this study was to investigate the safety of and yield from IS in children hospitalised with suspected pulmonary tuberculosis (PTB). METHODS: In a prospective study of children hospitalised with suspected PTB in Cape Town, South Africa, between February 2009 and February 2012, two IS specimens were obtained on consecutive days or at intervals of at least 4 hours. Specimens were investigated for M. tuberculosis using concentrated fluorescent acid-fast smear, liquid culture and GeneXpert(®) MTB/RIF. The safety of IS was assessed by recording clinical signs and symptoms before and for 30 min after sputum induction. RESULTS: Among 843 children enrolled, at least one IS was performed for 823 (97.6%). The safety of sputum induction was recorded for 690 children (median age 27.3 months [IQR 13.4-64.2]), representing a total of 1270 IS procedures. Of these, 129 (18.7%) had at least one sputum culture positive for M. tuberculosis. Side effects were epistaxis (249, 19.4%) or wheezing (14, 1.1%). The median drop in oxygen saturation during the IS procedure was 1%. CONCLUSION: Sputum induction is a safe and useful method for the microbiological confirmation of tuberculosis (TB) in young children.