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1.
Int J Obstet Anesth ; 33: 40-45, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29017742

RESUMO

BACKGROUND: Core-to-peripheral redistribution of heat, secondary to sympathetic-mediated vasodilation, is the major mechanism leading to early perioperative hypothermia after neuraxial anesthesia. The study aim was to determine if preoperative anterior thigh (peripheral lower extremity) temperature predicted perioperative temporal (core) temperature decrease during cesarean delivery with spinal anesthesia. METHODS: Secondary analysis of data derived from a prospective, randomized study of 46 healthy women undergoing scheduled cesarean delivery with spinal anesthesia was performed. Anterior thigh temperature was measured preoperatively prior to spinal anesthesia. The primary outcome was maximum perioperative temporal temperature decrease. Secondary outcomes included incidence of temporal hypothermia (temperature <36°C), shivering, and thermal comfort scores. This study ran concurrently with a previously published trial comparing no active intraoperative warming with active warming. RESULTS: There was no correlation between preoperative anterior thigh temperature and maximum perioperative temporal temperature decrease (r=-0.049, P=0.751). The mean±standard deviation preoperative anterior thigh temperature of women who developed temporal hypothermia compared to those who did not was 32.4±0.8°C versus 32.4±0.70°C respectively (P=0.995). Preoperative anterior thigh temperature did not correlate with the incidence of shivering (r=0.267, P=0.080) or thermal comfort scores (r=0.233, P=0.129). CONCLUSION: Preoperative anterior thigh temperature does not correlate with the degree of perioperative temporal temperature decrease, likelihood of developing hypothermia, shivering, or thermal comfort during cesarean delivery with spinal anesthesia. Although core-to-peripheral redistribution of heat after neuraxial anesthesia is a major mechanism of perioperative heat loss, a lower extremity temperature prediction hypothesis was not confirmed in this population.


Assuntos
Anestesia Obstétrica/métodos , Raquianestesia/métodos , Temperatura Corporal/fisiologia , Cesárea/efeitos adversos , Hipotermia/etiologia , Temperatura Cutânea/fisiologia , Coxa da Perna/fisiologia , Adolescente , Adulto , Feminino , Humanos , Hipotermia/terapia , Conforto do Paciente , Gravidez , Estudos Prospectivos , Reaquecimento , Estremecimento , Resultado do Tratamento , Adulto Jovem
2.
Science ; 358(6370): 1559-1565, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29038373

RESUMO

Merging neutron stars offer an excellent laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart (EM170817) with gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic data set, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultrarelativistic jets. Instead, we suggest that breakout of a wide-angle, mildly relativistic cocoon engulfing the jet explains the low-luminosity gamma rays, the high-luminosity ultraviolet-optical-infrared, and the delayed radio and x-ray emission. We posit that all neutron star mergers may lead to a wide-angle cocoon breakout, sometimes accompanied by a successful jet and sometimes by a choked jet.

3.
Anaesthesia ; 72(7): 879-888, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28407211

RESUMO

Optimal immunological homoeostasis determines the long-term recovery of patients in the postoperative period. The functional adaptability of monocytes plays a pivotal role in adjusting the host's response to an insult, immunostasis and long-term health, and may help to determine successful recovery. We undertook a longitudinal analysis of the functional adaptability of monocytes in 20 patients undergoing heart surgery with cardiopulmonary bypass, as a model of severe stress. Using each patient's pre-cardiopulmonary bypass data as a baseline, we investigated the characteristics of peripheral blood monocytes' functional plasticity in-vitro before elective bypass, and three months afterwards. Approximately 30% of subjects showed diminished monocyte plasticity, as demonstrated by decreased monocyte differentiation into dendritic cells three months after bypass. Diminished monocyte functional plasticity was related to over-production of macrophage colony-stimulating factor. Adding a neutralising antibody to macrophage colony-stimulating factor corrected the monocytes' differentiation defect. Finally, patients with reduced monocyte plasticity had significantly elevated serum C-reactive protein, with a concomitant increase in cytomegalovirus IgG antibody titres, suggestive of the acquisition of immuno-suppressive traits. Our study shows that severe surgical stress resulted in a lasting immunological defect in individuals who had seemingly recovered.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Monócitos/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Lectinas Tipo C/análise , Fator Estimulador de Colônias de Macrófagos/biossíntese , Masculino , Receptor de Manose , Lectinas de Ligação a Manose/análise , Pessoa de Meia-Idade , Receptores de Superfície Celular/análise
4.
Int J Obstet Anesth ; 30: 76, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28129934
5.
Int J Obstet Anesth ; 26: 32-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26775896

RESUMO

INTRODUCTION: The aim of this impact study was to compare the analgesic efficacy and side effect profile of programmed intermittent epidural boluses (PIEB)+patient-controlled epidural analgesia (PCEA) to continuous epidural infusion (CEI)+PCEA for maintenance labor analgesia after the introduction of PIEB at our institution. METHODS: We conducted a retrospective analysis after replacing the background CEI with PIEB for our labor PCEA. Pre-change pump settings were CEI 12mL/h with PCEA (12mL bolus, lockout 15min); PIEB settings were a 9mL bolus every 45min with PCEA (10mL bolus, lockout 10min). We compared medical records of all women receiving epidural or combined spinal-epidural labor analgesia for vaginal delivery for two months before PIEB implementation to a two-month period of PIEB utilization following a five-month introductory familiarization period. The primary outcome was the proportion of women requiring rescue clinician boluses. RESULTS: Fewer patients in the PIEB group required rescue clinician boluses compared to the CEI group (12% vs. 19%, P=0.012). Time to first rescue bolus request and total bolus dose were not different. Peak (median [IQR]) pain scores were 2[0-5] with CEI and 0[0-4] with PIEB. There was no difference in instrumental delivery rates. CONCLUSIONS: Using PIEB compared to CEI as the background maintenance epidural analgesia method in conjunction with PCEA reduced the number of women requiring clinician rescue boluses while providing comparable labor analgesia. The findings of this clinical care impact study confirm the results of randomized controlled studies and suggest PIEB may be a preferable technique to CEI for the maintenance of labor analgesia.


Assuntos
Analgesia Epidural/métodos , Analgesia Obstétrica/métodos , Adulto , Analgesia Controlada pelo Paciente , Feminino , Humanos , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
6.
ACS Appl Mater Interfaces ; 7(6): 3671-5, 2015 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-25607589

RESUMO

We have investigated the nucleation and growth of InGaZnO thin films by spatial atmospheric atomic layer deposition. Diethyl zinc (DEZ), trimethyl indium (TMIn), triethyl gallium (TEGa), and water were used as Zn, In, Ga and oxygen precursors, respectively. The vaporized metal precursors have been coinjected in the reactor. The metal composition of InGaZnO has been controlled by varying the TMIn or TEGa flow to the reactor, for a given DEZ flow and exposure time. The morphology of the films changes from polycrystalline, for ZnO and In-doped ZnO, to amorphous for In-rich IZO and InGaZnO. The use of these films as the active channel in TFTs has been demonstrated and the influence of In and Ga cations on the electrical characteristics of the TFTs has been studied.

8.
Aliment Pharmacol Ther ; 39(1): 85-92, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24206524

RESUMO

BACKGROUND: Early on-treatment virological response is one of the most important predictors for sustained virological response (SVR) to treatment of chronic hepatitis C virus (HCV) genotype 1 infection with triple therapy including HCV protease inhibitors (PI). Treatment duration (24 vs. 48 weeks) is based on HCV RNA results at weeks 4 and 12 of PI therapy when HCV RNA must be 'undetectable' to allow shorter therapy. AIM: To analyse the reliability of HCV RNA measurements at key decision time points (weeks 4 and 12) and the predictive value of concordant or discordant assay results for SVR. METHODS: Weeks 4 and 12 samples of patients receiving telaprevir-containing triple therapy were initially tested with the AmpliPrep/COBAS-TaqMan_HCV-Test-v1.0 (limit of detection; LOD = 15IU/mL) and retested with the AmpliPrep/COBAS-TaqMan_HCV-Test-v2.0 (LOD = 15IU/mL) and the High_Pure/COBAS-TaqMan_HCV-Test-v2.0 (LOD = 20IU/mL). RESULTS: Concordance among the three test results in classifying samples as HCV RNA 'undetectable' or 'detectable' was only 55% at week 4, but 85% at week 12. Retesting of 'undetectable' week 4 samples with the respective other assays revealed positive HCV RNA results in 32-50%. In 30%, HCV RNA was 'undetectable' by all three tests at week 4 and all of these patients achieved SVR. In contrast, treatment failure occurred in 62% of patients with at least one 'detectable' result, including cases with one or two other 'undetectable' tests at week 4. CONCLUSIONS: A single 'undetectable' HCV RNA result at week 4 is not always associated with achieving SVR. Repeated testing in difficult-to-treat patients may identify those at risk for treatment failure.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , RNA Viral/análise , Adulto , Quimioterapia Combinada , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Pessoa de Meia-Idade , Oligopeptídeos/uso terapêutico , Polietilenoglicóis/uso terapêutico , Inibidores de Proteases/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Falha de Tratamento , Viremia/genética
9.
Clin Genet ; 68(1): 23-30, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15952982

RESUMO

Hermansky-Pudlak syndrome (HPS) is an autosomal recessive disorder characterized by oculocutaneous albinism, a bleeding diathesis and, in some patients, pulmonary fibrosis or granulomatous colitis. HPS is associated with biosynthesis defects of melanosomes, platelet-dense bodies, and lysosomes. There are seven genetic HPS subtypes; HPS-1 is the most common. We used a real-time quantitative PCR (qPCR) approach to investigate six HPS-1 patients, previously assigned as having homozygous mutations in the HPS1 gene. HPS1 gene copy numbers, calculated by use of a comparative Ct method, revealed that one patient was in fact hemizygous for her c.1189delC (S396delC) HPS1 mutation. The causative deletion/insertion was 13,966 bp in size, with defined breakpoints, and involved an adjacent gene (C10orf33). A mechanism of formation is proposed for the deletion/insertion, and both multiplex and qPCR indicated that the deletion/insertion was present in the patient, her brother, and her father. qPCR amplification is valuable for detecting deletions too small to be identified by fluorescence in situ hybridization. This demonstration of hemizygosity, performed using genomic DNA, can eliminate concerns about non-paternity and can verify the diagnosis of an autosomal recessive disorder when a DNA alteration appears to be homozygous by standard PCR and sequencing methods, and its pathogenicity is in doubt.


Assuntos
Síndrome de Hermanski-Pudlak/genética , Homozigoto , Proteínas de Membrana/genética , Reação em Cadeia da Polimerase/métodos , Adolescente , Adulto , Sequência de Bases , Cromossomos Humanos Par 10 , Feminino , Humanos , Masculino , Mitocôndrias/genética , Dados de Sequência Molecular , Mutação , Linhagem , Deleção de Sequência
10.
Curr Top Microbiol Immunol ; 290: 29-47, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16480038

RESUMO

The regulatory steps that lead to the differentiation of hematopoietic cells from a multipotential stem cell remain largely unknown. A beginning to the understanding of these steps has come from the study of DNA-binding proteins that are thought to regulate the expression of genes required for specific developmental events. Ikaros is the founding member of a small family of DNA-binding proteins required for lymphocyte development, but the members of this family differ from other key regulators of lymphopoiesis in that direct target genes have not been conclusively identified, and reasonable support has been presented for only a few potential targets. Therefore, the molecular mechanisms that Ikaros uses for regulating lymphocyte development remain largely unknown. Current data suggest that, in some instances, Ikaros may function as a typical transcription factor. However, recent results suggest that it may function more broadly, perhaps in the formation of silent and active chromatin structures. In this review, our current knowledge of the molecular functions of Ikaros will be discussed.


Assuntos
Fator de Transcrição Ikaros/fisiologia , Linfócitos/fisiologia , Linfopoese , Animais , Diferenciação Celular , Centrômero/metabolismo , Cromatina/metabolismo , Regulação da Expressão Gênica , Humanos , Fator de Transcrição Ikaros/química , Fator de Transcrição Ikaros/genética
11.
J Inherit Metab Dis ; 27(2): 157-63, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15159646

RESUMO

Classical phenylketonuria (PKU) and mild hyperphenylalaninaemia (MHP) are two ends of the broad diagnostic spectrum in phenylalanine hydroxylase (PAH) deficiency. We have analysed a family in which classical PKU, MHP and a normal phenotype occurred in family members with different mutations. Sequence analysis revealed three mutations segregating in the family. The individual with classical PKU had two previously reported deleterious mutations. A third novel mutation was identified in the other two individuals. This report demonstrates that when discordant phenotypes occur in a family, without protein loading or phenylalanine tolerance test, complete analysis of the PAH gene may be performed in order to support the diagnosis and assist in accurate genetic counselling and patient management.


Assuntos
Fenilalanina Hidroxilase/genética , Fenilcetonúrias/genética , Mutação Puntual , Alelos , Pré-Escolar , Análise Mutacional de DNA , Saúde da Família , Feminino , Genótipo , Humanos , Masculino , Linhagem , Fenótipo , Irmãos
12.
Am J Physiol Lung Cell Mol Physiol ; 282(1): L12-25, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11741811

RESUMO

We investigated adenosine (Ado) activation of the cystic fibrosis transmembrane conductance regulator (CFTR) in vitro and in vivo. A(2B) Ado receptors were identified in Calu-3, IB-3-1, COS-7, and primary human airway cells. Ado elevated cAMP in Calu-3, IB-3-1, and COS-7 cells and activated protein kinase A-dependent halide efflux in Calu-3 cells. Ado promoted arachidonic acid release from Calu-3 cells, and phospholipase A(2) (PLA(2)) inhibition blocked Ado-activated halide efflux in Calu-3 and COS-7 cells expressing CFTR. Forskolin- and beta(2)-adrenergic receptor-stimulated efflux were not affected by the same treatment. Cytoplasmic PLA(2) (cPLA(2)) was identified in Calu-3, IB-3-1, and COS-7 cells, but cPLA(2) inhibition did not affect Ado-stimulated cAMP concentrations. In cftr(+) and cftr(-/-) mice, Ado stimulated nasal Cl(-) secretion that was CFTR dependent and sensitive to A(2) receptor and PLA(2) blockade. In COS-7 cells transiently expressing DeltaF508 CFTR, Ado activated halide efflux. Ado also activated G551D CFTR-dependent halide efflux when combined with arachidonic acid and phosphodiesterase inhibition. In conclusion, PLA(2) and protein kinase A both contribute to A(2) receptor activation of CFTR, and components of this signaling pathway can augment wild-type and mutant CFTR activity.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Fosfolipases A/fisiologia , Receptores Purinérgicos P1/fisiologia , Adenilil Ciclases/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Células COS , Linhagem Celular , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/fisiologia , Humanos , Camundongos , Isoformas de Proteínas/fisiologia
13.
Nucleic Acids Res ; 29(23): E119, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11726702

RESUMO

Allele-specific amplification (ASA) is a generally applicable technique for the detection of known single nucleotide polymorphisms (SNPs), deletions, insertions and other sequence variations. Conventionally, two reactions are required to determine the zygosity of DNA in a two-allele system, along with significant upstream optimisation to define the specific test conditions. Here, we combine single tube bi-directional ASA with a 'matrix-based' optimisation strategy, speeding up the whole process in a reduced reaction set. We use sickle cell anaemia as our model SNP system, a genetic disease that is currently screened using ASA methods. Discriminatory conditions were rapidly optimised enabling the unambiguous identification of DNA from homozygous sickle cell patients (HbS/S), heterozygous carriers (HbA/S) or normal DNA in a single tube. Simple downstream mathematical analyses based on product yield across the optimisation set allow an insight into the important aspects of priming competition and component interactions in this competitive PCR. This strategy can be applied to any polymorphism, defining specific conditions using a multifactorial approach. The inherent simplicity and low cost of this PCR-based method validates bi-directional ASA as an effective tool in future clinical screening and pharmacogenomic research where more expensive fluorescence-based approaches may not be desirable.


Assuntos
Anemia Falciforme/genética , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Nucleotídeo Único , Alelos , Anemia Falciforme/diagnóstico , Genótipo , Hemoglobina Falciforme/genética , Humanos , Sensibilidade e Especificidade
14.
Pediatrics ; 108(5): E85, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11694669

RESUMO

OBJECTIVE: The purpose of the study was to examine the association between adolescents' psychological distress and their sexually transmitted disease/human immunodeficiency virus (STD/HIV)-associated sexual behaviors and attitudes. METHOD: Sexually active black adolescent females (N = 522) completed, at baseline and again 6 months later, a self-administered questionnaire that assessed sexual health attitudes and emotional distress symptoms (using standardized measures, alpha =.84), a structured interview that assessed STD/HIV-associated sexual risk behaviors, and a urine screen for pregnancy. RESULTS: In multivariate analyses, controlling for observed covariates, adolescents with significant distress at baseline were more likely than their peers, after 6 months, to be pregnant (adjusted odds ratio [AOR]: = 2.0), have had unprotected vaginal sex (AOR = 2.1), have nonmonogamous sex partners (AOR = 1.7), and not use any form of contraception (AOR = 1.5). Additionally, they were also more likely to: perceive barriers to condom use (AOR = 2.2), be fearful of the adverse consequences of negotiating condom use (AOR = 2.0), perceive less control in their relationship (AOR = 2.0), have experienced dating violence (AOR = 2.4), feel less efficacious in negotiating condom use with a new sex partner (AOR = 1.6), and have norms nonsupportive of a healthy sexual relationship (AOR = 1.7). DISCUSSION: The findings suggest that psychological distress is predictive over a 6-month period of a spectrum of STD/HIV-associated sexual behaviors and high-risk attitudes. Brief screening to detect distress or depressive symptoms among adolescent females can alert the clinician to the need to conduct a sexual health history, initiate STD/HIV-preventive counseling, and refer for comprehensive psychological assessment and appropriate treatment. Among adolescents receiving STD treatment, those with even moderate emotional distress may be at heightened risk for further unhealthy outcomes. STD/HIV interventions should also consider psychological distress as one potential risk factor that may impact program efficacy.


Assuntos
Negro ou Afro-Americano/psicologia , Transtorno Depressivo/diagnóstico , Assunção de Riscos , Comportamento Sexual , Adolescente , Análise de Variância , Preservativos/estatística & dados numéricos , Comportamento Contraceptivo/psicologia , Escolaridade , Características da Família , Medo , Feminino , Humanos , Relações Interpessoais , Saúde Mental , Gravidez , Gravidez na Adolescência/psicologia , Estudos Prospectivos , Fatores Socioeconômicos
15.
J Pediatr Adolesc Gynecol ; 14(3): 123-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11675229

RESUMO

STUDY OBJECTIVE: The purpose of this study was to determine correlates of worry about pregnancy among a high-risk sample of low-income African-American adolescent females. Specifically, we tested the hypothesis that perceived male partner desire for pregnancy and level of sexual communication would be independently associated with adolescent females' worry about becoming pregnant. DESIGN: A survey of sexually active African-American adolescent females, 14-18 years of age. SETTING: Recruitment was conducted in low-income neighborhoods of Birmingham, Alabama, characterized by high rates of unemployment, substance abuse, violence, and teen pregnancy. PARTICIPANTS: Adolescents (N = 522) completed a survey and a face-to-face interview, and provided a urine specimen for pregnancy testing. MAIN OUTCOME MEASURE: Nonpregnant adolescents reporting steady relationships with a male sex partner (over the past 6 months) and indicating no immediate desire to become pregnant were included in the analysis (n = 196). Two questionnaire items assessed level of worry about becoming pregnant. RESULTS: Compared to adolescent females reporting their partner did not desire pregnancy, those perceiving their partner desired pregnancy were nearly three times more likely to experience high worry about becoming pregnant (AOR = 2.85; P =.009). Engaging in sex unprotected by a condom was an equally important correlate of high worry (AOR = 2.84; P =.013). Level of communication between partners about pregnancy prevention was not significant. CONCLUSIONS: Adolescent females may experience high worry about becoming pregnant due to desires of their male partner as well as their recent sexual risk behavior.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Gravidez na Adolescência/prevenção & controle , Gravidez não Desejada/etnologia , Gravidez não Desejada/estatística & dados numéricos , Gravidez/fisiologia , Assunção de Riscos , Adolescente , Alabama/epidemiologia , Intervalos de Confiança , Serviços de Planejamento Familiar , Feminino , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Incidência , Modelos Logísticos , Razão de Chances , Vigilância da População , Gravidez na Adolescência/estatística & dados numéricos , Fatores de Risco , Sexualidade , Estresse Psicológico
16.
J Pediatr ; 139(3): 407-12, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11562621

RESUMO

OBJECTIVE: To examine associations between parent-adolescent communication about sex-related topics and the sex-related communication and practices of African American adolescent females with partners, as well as their perceived ability to negotiate safer sex. DESIGN: A theory-guided survey and structured interview were administered to 522 sexually active African American females 14 to 18 years old. Recruitment sites were neighborhoods with high rates of unemployment, substance abuse, violence, and sexually transmitted diseases. Multivariate analyses, controlling for observed covariates, were used to identify the association of less frequent parent-adolescent communication with multiple assessed outcomes. RESULTS: Less frequent parent-adolescent communication (scores below the median) was associated with adolescents' non-use of contraceptives in the past 6 months (adjusted odds ratio [AOR] = 1.7) and non-use of contraceptives during the last 5 sexual encounters (AOR = 1.6). Less communication increased the odds of never using condoms in the past month (AOR = 1.6), during the last 5 sexual encounters (AOR = 1.7), and at last intercourse (AOR = 1.7). Less communication was also associated with less communication between adolescents and their sex partners (AOR = 3.3) and lower self-efficacy to negotiate safer sex (AOR = 1.8). CONCLUSIONS: The findings demonstrate the importance of involving parents in human immunodeficiency virus/sexually transmitted disease and pregnancy prevention efforts directed at female adolescents. Pediatricians and other clinicians can play an important role in facilitating parent-adolescent communication about sexual activity.


Assuntos
Comportamento do Adolescente , Negro ou Afro-Americano , Comunicação , Relações Pais-Filho , Pobreza , Sexo Seguro , Infecções Sexualmente Transmissíveis/prevenção & controle , Adolescente , Adulto , Análise de Variância , Preservativos/estatística & dados numéricos , Feminino , Humanos , Fatores de Risco , Autoeficácia
17.
Bioelectromagnetics ; 22(6): 429-39, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11536284

RESUMO

Permission was received from the Brooks AFB Institutional Review Board and the AF Surgeon General's Office to exceed the peak power density (PD = 35 mW/cm(2)) we had previously studied during partial body exposure of human volunteers at 2450 MHz. Two additional peak PD were tested (50 and 70 mW/cm(2)). The higher of these PD (normalized peak local SAR = 15.4 W/kg) is well outside the IEEE C95.1 guidelines for partial body exposure, as is the estimated whole body SAR approximately 1.0 W/kg. Seven volunteers (four males, three females) were tested at each PD in three ambient temperatures (T(a) = 24, 28, and 31 degrees C) under our standard protocol (30 min baseline, 45 min RF exposure, 10 min baseline). The thermophysiological data (esophageal and six skin temperatures, metabolic heat production, local sweat rate, and local skin blood flow) were combined with comparable data at PD = 0, 27, and 35 mW/cm(2) from our 1999 study to generate response functions across PD. No change in esophageal temperature or metabolic heat production was recorded at any PD in any T(a). At PD = 70 mW/cm(2), skin temperature on the upper back (irradiated directly) increased 4.0 degrees C in T(a) = 24 degrees C, 2.6 degrees C in T(a) = 28 degrees C, and 1.8 degrees C in T(a) = 31 degrees C. These differences were primarily due to the increase in local sweat rate, which was greatest in T(a) = 31 degrees C. Also at PD = 70 mW/cm(2), local skin blood flow on the back increased 65% over baseline levels in T(a) = 31 degrees C, but only 40% in T(a) = 24 degrees C. Although T(a) becomes an important variable when RF exposure exceeds the C95.1 partial body exposure limits, vigorous heat loss responses of blood flow and sweating maintain thermal homeostasis efficiently. It is also clear that strong sensations of heat and thermal discomfort will motivate a timely retreat from a strong RF field, long before these physiological responses are exhausted. Published 2001 Wiley-Liss, Inc.


Assuntos
Regulação da Temperatura Corporal/efeitos da radiação , Temperatura Corporal/efeitos da radiação , Campos Eletromagnéticos , Micro-Ondas , Adulto , Idoso , Temperatura Corporal/fisiologia , Metabolismo Energético/efeitos da radiação , Exposição Ambiental , Esôfago , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/efeitos da radiação , Pele/irrigação sanguínea , Temperatura Cutânea/efeitos da radiação , Sudorese/fisiologia , Sudorese/efeitos da radiação , Temperatura , Fatores de Tempo
18.
J Adolesc Health ; 29(3): 194-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11524218

RESUMO

PURPOSE: To assess condom application ability and the relationship between perceived ability and demonstrated ability. Also, to examine the association between high-demonstrated condom application ability and recent sexual risk behaviors and laboratory-diagnosed sexually transmitted diseases (STDs) among African-American adolescent females. METHODS: A purposeful sample of sexually active African-American females (n = 522) completed a structured interview and provided vaginal swab specimens for STD testing. Subsequent to the interview, adolescents demonstrated their condom application skills using a penile model. A 9-item scale assessed adolescents' perceived self-efficacy to apply condoms. Sexual risk behaviors assessed by interview were noncondom use at last intercourse and the last five intercourse occasions for steady and casual sex partners as well as any unprotected vaginal sex in the past 30 days and the past 6 months. RESULTS: Approximately 28% of the sample tested positive for at least one STD and nearly 26% self-reported a history of STDs. Controlled analyses indicated that adolescents' self-efficacy for correct use was not related to demonstrated skill. Adolescents' demonstrated ability was not related to any of the sexual risk behaviors. Likewise, recent experience applying condoms to a partner's penis and demonstrated ability were not related to laboratory-diagnosed STDs or self-reported STD history. CONCLUSIONS: Adolescents may unknowingly be at risk for human immunodeficiency virus and STD infection owing to incorrect condom application. Further, high-demonstrated ability to apply condoms was not related to safer sex or STDs. Reducing sexual risk behaviors may require more than enhancing adolescent females' condom application skills and may require addressing other relational skills.


Assuntos
Negro ou Afro-Americano/psicologia , Preservativos/estatística & dados numéricos , Comportamento Contraceptivo/psicologia , Psicologia do Adolescente , Autoeficácia , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções Sexualmente Transmissíveis/psicologia , Adolescente , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Assunção de Riscos , Parceiros Sexuais , Inquéritos e Questionários , Estados Unidos
19.
Prev Med ; 33(3): 175-8, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11522158

RESUMO

BACKGROUND: The joint influence of living with the mother in a perceived supportive family may be an important HIV/STD-protective factor among sexually active female adolescents. METHODS: Sexually active African American female adolescents (N = 522) completed a self-administered survey and structured interview. Adolescents scoring high on family support and reporting that their mother lived with them were compared with the remaining adolescents in respect to unprotected vaginal sex (past 30 days), sex with a non-steady partner (past 6 months), communication with sex partners, attitudes toward condoms, and perceived ability to negotiate condom use. Logistic regression analyses controlled for the influence of parent-adolescent communication about sex and parental monitoring. RESULTS: Adolescents residing with their mothers in a perceived supportive family were more likely to communicate with their sex partners about sexual risk (OR = 1.53). They were less likely to report sex with a non-steady partner (OR = 0.51) or having unprotected sex with a steady partner (OR = 0.52) or any partner (OR = 0.55). CONCLUSIONS: Controlled analyses suggest that living with the mother in a perceived supportive family is an important HIV/STD-protective factor among female adolescents. HIV/STD prevention programs for female adolescents that include the mothers may promote positive and lasting effects.


Assuntos
Características da Família , Infecções por HIV/prevenção & controle , Relações Mãe-Filho , Comportamento Sexual , Infecções Sexualmente Transmissíveis/prevenção & controle , Adolescente , Negro ou Afro-Americano/estatística & dados numéricos , Feminino , Infecções por HIV/psicologia , Humanos , Modelos Logísticos , Razão de Chances , Comportamento Sexual/psicologia , Infecções Sexualmente Transmissíveis/psicologia , Apoio Social , Estados Unidos
20.
Sex Transm Dis ; 28(8): 444-7, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11473215

RESUMO

BACKGROUND: Most of the studies associated with condom carrying and use have been conducted with adults. Because minority teenage females are particularly at risk for STD/HIV infection, further investigations specifically focusing on this population are warranted. GOAL: To determine whether observed condom carrying among adolescent females was associated with multiple measures of self-reported condom use, self-reported history of sexually transmitted diseases, and prevalence of biologically confirmed sexually transmitted diseases. METHODS: For this study, 522 sexually active African American adolescent females were recruited from low-income neighborhoods in Birmingham, Alabama. Measures of self-reported condom use, STD history, and condom carrying were collected. Adolescents were also tested for three prevalent sexually transmitted diseases. RESULTS: At the time of the assessment, 8% of the adolescents were observed to have a condom with them. Condom carrying was not found to be significantly associated with condom use and prevalence of sexually transmitted diseases. CONCLUSION: Condom carrying may not be an important outcome of sexually transmitted disease/HIV prevention programs designed to reduce HIV/sexually transmitted disease risk among adolescent females.


Assuntos
Comportamento do Adolescente , Preservativos/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/epidemiologia , Adolescente , Negro ou Afro-Americano/estatística & dados numéricos , Alabama/epidemiologia , Infecções por Chlamydia/epidemiologia , Infecções por Chlamydia/prevenção & controle , Feminino , Gonorreia/epidemiologia , Gonorreia/prevenção & controle , Humanos , Infecções Sexualmente Transmissíveis/prevenção & controle , Fatores Socioeconômicos , Vaginite por Trichomonas/epidemiologia , Vaginite por Trichomonas/prevenção & controle , Vagina/microbiologia , Saúde da Mulher
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