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1.
Int J Tuberc Lung Dis ; 28(5): 243-248, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38659142

RESUMO

BACKGROUNDThe inclusion of adolescents in TB drug trials is essential for the development of safe, child-friendly regimens for the prevention and treatment of TB. TB Trials Consortium Study 31/AIDS Clinical Trials Group A5349 (S31/A5349) enrolled adolescents as young as 12 years old. We assessed investigator and coordinator described facilitators and barriers to adolescent recruitment, enrollment, and retention.METHODSInterviews were conducted with six investigators from sites that enrolled adolescent participants and six investigators from non-enrolling sites. Additionally, two focus groups were conducted with study coordinators from enrolling sites and two focus groups with non-enrolling sites. Discussions were transcribed, analyzed, summarized, and summaries were reviewed by Community Research Advisors Group members and research group representatives for content validity.RESULTSInvestigators and coordinators attributed the successful enrollment of adolescents to the establishment and cultivation of external partnerships, flexibility to accommodate adolescents' schedules, staff engagement, recruitment from multiple locations, dedicated recruitment staff working onsite to access potential participants, creation of youth-friendly environments, and effective communications. Non-enrolling sites were mainly hindered by regulations. Suggestions for improvement in future trials focused on study planning and site preparations.CONCLUSIONProactive partnerships and collaboration with institutions serving adolescents helped identify and reduce barriers to their inclusion in this trial..


Assuntos
Grupos Focais , Seleção de Pacientes , Tuberculose , Humanos , Adolescente , Tuberculose/tratamento farmacológico , Feminino , Masculino , Criança , Antituberculosos/administração & dosagem , Ensaios Clínicos como Assunto , Pesquisadores
2.
Environ Sci Process Impacts ; 21(2): 224-241, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30452047

RESUMO

Accurate and precise analyses of oil and gas (O&G) wastewaters and solids (e.g., sediments and sludge) are important for the regulatory monitoring of O&G development and tracing potential O&G contamination in the environment. In this study, 15 laboratories participated in an inter-laboratory comparison on the chemical characterization of three O&G wastewaters from the Appalachian Basin and four solids impacted by O&G development, with the goal of evaluating the quality of data and the accuracy of measurements for various analytes of concern. Using a variety of different methods, analytes in the wastewaters with high concentrations (i.e., >5 mg L-1) were easily detectable with relatively high accuracy, often within ±10% of the most probable value (MPV). In contrast, often less than 7 of the 15 labs were able to report detectable trace metal(loid) concentrations (i.e., Cr, Ni, Cu, Zn, As, and Pb) with accuracies of approximately ±40%. Despite most labs using inductively coupled plasma mass spectrometry (ICP-MS) with low instrument detection capabilities for trace metal analyses, large dilution factors during sample preparation and low trace metal concentrations in the wastewaters limited the number of quantifiable determinations and likely influenced analytical accuracy. In contrast, all the labs measuring Ra in the wastewaters were able to report detectable concentrations using a variety of methods including gamma spectroscopy and wet chemical approaches following Environmental Protection Agency (EPA) standard methods. However, the reported radium activities were often greater than ±30% different to the MPV possibly due to calibration inconsistencies among labs, radon leakage, or failing to correct for self-attenuation. Reported radium activities in solid materials had less variability (±20% from MPV) but accuracy could likely be improved by using certified radium standards and accounting for self-attenuation that results from matrix interferences or a density difference between the calibration standard and the unknown sample. This inter-laboratory comparison illustrates that numerous methods can be used to measure major cation, minor cation, and anion concentrations in O&G wastewaters with relatively high accuracy while trace metal(loid) and radioactivity analyses in liquids may often be over ±20% different from the MPV.


Assuntos
Compostos Inorgânicos/análise , Laboratórios/organização & administração , Petróleo/análise , Poluentes Radioativos/análise , Águas Residuárias/química , Região dos Apalaches
3.
Clin Pharmacol Ther ; 102(2): 321-331, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28124478

RESUMO

Rifapentine is a highly active antituberculosis antibiotic with treatment-shortening potential; however, exposure-response relations and the dose needed for maximal bactericidal activity have not been established. We used pharmacokinetic/pharmacodynamic data from 657 adults with pulmonary tuberculosis participating in treatment trials to compare rifapentine (n = 405) with rifampin (n = 252) as part of intensive-phase therapy. Population pharmacokinetic/pharmacodynamic analyses were performed with nonlinear mixed-effects modeling. Time to stable culture conversion of sputum to negative was determined in cultures obtained over 4 months of therapy. Rifapentine exposures were lower in participants who were coinfected with human immunodeficiency virus, black, male, or fasting when taking drug. Rifapentine exposure, large lung cavity size, and geographic region were independently associated with time to culture conversion in liquid media. Maximal treatment efficacy is likely achieved with rifapentine at 1,200 mg daily. Patients with large lung cavities appear less responsive to treatment, even at high rifapentine doses.


Assuntos
Antibióticos Antituberculose/administração & dosagem , Antibióticos Antituberculose/farmacocinética , Rifampina/análogos & derivados , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/metabolismo , Adulto , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Rifampina/administração & dosagem , Rifampina/farmacocinética , Tuberculose Pulmonar/epidemiologia
4.
Sci Total Environ ; 579: 1781-1793, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27939081

RESUMO

Wastewaters from oil and gas development pose largely unknown risks to environmental resources. In January 2015, 11.4ML (million liters) of wastewater (300g/L TDS) from oil production in the Williston Basin was reported to have leaked from a pipeline, spilling into Blacktail Creek, North Dakota. Geochemical and biological samples were collected in February and June 2015 to identify geochemical signatures of spilled wastewaters as well as biological responses along a 44-km river reach. February water samples had elevated chloride (1030mg/L) and bromide (7.8mg/L) downstream from the spill, compared to upstream levels (11mg/L and <0.4mg/L, respectively). Lithium (0.25mg/L), boron (1.75mg/L) and strontium (7.1mg/L) were present downstream at 5-10 times upstream concentrations. Light hydrocarbon measurements indicated a persistent thermogenic source of methane in the stream. Semi-volatile hydrocarbons indicative of oil were not detected in filtered samples but low levels, including tetramethylbenzenes and di-methylnaphthalenes, were detected in unfiltered water samples downstream from the spill. Labile sediment-bound barium and strontium concentrations (June 2015) were higher downstream from the Spill Site. Radium activities in sediment downstream from the Spill Site were up to 15 times the upstream activities and, combined with Sr isotope ratios, suggest contributions from the pipeline fluid and support the conclusion that elevated concentrations in Blacktail Creek water are from the leaking pipeline. Results from June 2015 demonstrate the persistence of wastewater effects in Blacktail Creek several months after remediation efforts started. Aquatic health effects were observed in June 2015; fish bioassays showed only 2.5% survival at 7.1km downstream from the spill compared to 89% at the upstream reference site. Additional potential biological impacts were indicated by estrogenic inhibition in downstream waters. Our findings demonstrate that environmental signatures from wastewater spills are persistent and create the potential for long-term environmental health effects.


Assuntos
Monitoramento Ambiental , Águas Residuárias/análise , Poluentes Químicos da Água/análise , North Dakota , Campos de Petróleo e Gás , Rios/química
5.
Neuroscience ; 138(4): 1277-87, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16427742

RESUMO

Loss of GABA-mediated inhibition in the spinal cord is thought to mediate allodynia and spontaneous pain after nerve injury. Despite extensive investigation of GABA itself, relatively little is known about how nerve injury alters the receptors at which GABA acts. This study examined levels of GABA(B) receptor protein in the spinal cord dorsal horn, and in the L4 and L5 (lumbar designations) dorsal root ganglia one to 18 weeks after L5 spinal nerve ligation. Mechanical allodynia was maximal by 1 week and persisted at blunted levels for at least 18 weeks after injury. Spontaneous pain behaviors were evident for 6 weeks. Western blotting of dorsal horn detected two isoforms of the GABA(B(1)) subunit and a single GABA(B(2)) subunit. High levels of GABA(B(1a)) and low levels of GABA(B(1b)) protein were present in the dorsal root ganglia. However, GABA(B(2)) protein was not detected in the dorsal root ganglia, consistent with the proposed existence of an atypical receptor composed of GABA(B(1)) homodimers. The levels of GABA(B(1a)), GABA(B(1b)), and GABA(B(2)) protein in the ipsilateral dorsal horn were unchanged at any time after injury. Immunohistochemical staining also did not detect a change in GABA(B(1)) or GABA(B(2)) subunits in dorsal horn segments having a robust loss of isolectin B4 staining. The levels of GABA(B(1a)) protein were also unchanged in the L4 or L5 dorsal root ganglia at any time after spinal nerve ligation. Levels of GABA(B(2)) remained undetectable. Finally, baclofen-stimulated binding of guanosine-5'-(gamma-O-thio)triphosphate in dorsal horn did not differ between sham and ligated rats. Collectively, these results argue that a loss of GABA(B) receptor-mediated inhibition, particularly of central terminals of primary afferents, is unlikely to mediate the development or maintenance of allodynia or spontaneous pain behaviors after spinal nerve injury.


Assuntos
Gânglios Espinais/metabolismo , Neuralgia/metabolismo , Traumatismos dos Nervos Periféricos , Nervos Periféricos/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , Células do Corno Posterior/metabolismo , Receptores de GABA-B/metabolismo , Animais , Baclofeno/farmacologia , Denervação , Modelos Animais de Doenças , Agonistas GABAérgicos/farmacologia , Gânglios Espinais/citologia , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Hiperalgesia/metabolismo , Hiperalgesia/fisiopatologia , Ligadura , Masculino , Inibição Neural/fisiologia , Neuralgia/fisiopatologia , Nervos Periféricos/fisiopatologia , Doenças do Sistema Nervoso Periférico/fisiopatologia , Células do Corno Posterior/citologia , Terminações Pré-Sinápticas/metabolismo , Subunidades Proteicas/metabolismo , Ratos , Ratos Sprague-Dawley , Transmissão Sináptica/fisiologia , Regulação para Cima/fisiologia , Ácido gama-Aminobutírico/metabolismo
6.
J Neurosci ; 19(19): 8509-16, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10493751

RESUMO

Mice that overexpress nerve growth factor (NGF-OE) in the skin have double the normal number of cutaneous sensory neurons, have increased innervation of the skin and spinal cord, and are hyperalgesic. Here, we have asked whether the increased cutaneous NGF level results in a selective survival of only certain functional types of neurons and whether it changes the properties of cutaneous neurons. Using electron microscopy, we show that the number of both myelinated and unmyelinated nociceptors increases substantially in NGF-OE mice by a factor of 3.3 and 1.5, respectively. Using extracellular recordings from single units, we demonstrate that large myelinated (Abeta) fibers are unchanged in prevalence and receptive properties. In contrast, among thin myelinated (Adelta) fibers, the percentage of nociceptors increased from a normal 65 to 97%, consistent with a selective survival of nociceptors during embryogenesis. These afferents showed a twofold increase in their mechanical responsiveness, but their heat responsiveness remained normal. Among unmyelinated (C) fibers, there was a profound increase in the percentage of heat responsive neurons from a normal 42 to 96%. This change cannot be accounted for by a selective survival of heat-sensitive neurons. Unmyelinated nociceptors increased fourfold in their thermal responsiveness but decreased in mechanical responsiveness. Therefore, target-derived NGF selectively rescues nociceptors during the period of programmed cell death with different efficacy for thin myelinated or unmyelinated fibers. NGF also affects the response to noxious heat or mechanical stimuli in each group differently, implying specific regulations of transduction processes rather than general changes of excitability.


Assuntos
Nervo Femoral/fisiologia , Fatores de Crescimento Neural/genética , Nociceptores/fisiologia , Pele/inervação , Pele/metabolismo , Animais , Axônios/fisiologia , Axônios/ultraestrutura , Membro Posterior , Técnicas In Vitro , Queratinas/genética , Camundongos , Camundongos Endogâmicos C3H , Camundongos Transgênicos , Fibras Nervosas/fisiologia , Fibras Nervosas Mielinizadas/fisiologia , Fatores de Crescimento Neural/fisiologia , Condução Nervosa , Nociceptores/citologia , Regiões Promotoras Genéticas
7.
Biochim Biophys Acta ; 923(2): 323-5, 1987 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-3814621

RESUMO

Fetal type II pneumocytes in organotypic culture can oxidize both palmitate and glucose, with glucose being converted to CO2 at a rate substantially greater than that of palmitate. Glucose can be oxidized by both the pentose shunt pathway and the tricarboxylic acid cycle. Palmitate oxidation to CO2 is increased by carnitine and reduced by glucose and unsaturated fatty acids. These data suggest that glucose may be an important oxidative substrate during late fetal life and that fatty acids may play a relatively minor role in type II cell oxidative metabolism.


Assuntos
Glucose/metabolismo , Pulmão/metabolismo , Palmitatos/metabolismo , Ácidos Palmíticos/metabolismo , Animais , Feto/metabolismo , Pulmão/embriologia , Oxirredução , Ratos
8.
Biochim Biophys Acta ; 1511(2): 369-80, 2001 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-11286980

RESUMO

Surfactant-like particle (SLP) is a phosphatidylcholine (PC)-rich membrane produced in the small intestine, and its secretion is increased by fat feeding. In Caco-2 cells known to produce SLP, preincubation with [(3)H]palmitate labelled the SLP and was used as a marker for newly secreted membrane. SLP-associated PC and protein (d=1.07-1.08 g/ml in a linear non-equilibrium NaBr gradient) were secreted in parallel with triacylglycerols (TG) and at a rate about twice the control rate in response to feeding cells with an oleate/egg PC mixture. Cholesterol and apolipoprotein A-I identified only a small peak corresponding to high-density lipoprotein (HDL), but the largest peak corresponded with SLP (d=1.07-1.08). Palmitate incorporation into PC showed a similar small peak migrating at the density of HDL, but most labelled PC secreted from the cells was due to SLP. PC secretion, alkaline phosphatase activity, and newly synthesized immunoprecipitated SLP proteins from conditioned serum-free media migrated together at a density of >/=1.21 g/ml in a lipoprotein NaBr step gradient, and represented SLP. Glycerol incorporated into TG migrated at a peak density of 1.12 g/ml, consistent with HDL secretion from cells incubated in serum-free media. These data confirm that the secreted PC in SLP is distinct from lipoprotein particles. Incorporation of [(3)H]palmitate into the PC fraction of either whole cell homogenate or isolated brush border membranes was not affected by oleate/egg PC feeding. Both Pluronic L-81, an inhibitor of chylomicron secretion, and BMS-197636-02, a microsomal triglyceride transfer protein inhibitor, blocked the secretion of both TG and PC. Elevation of intracellular cAMP levels that stimulate surfactant secretion from type II pneumocytes caused a 50% reduction in SLP and TG secretion from Caco-2 cells. These results confirm the SLP response to fat feeding found in vivo, further supporting a role for SLP in TG secretion from the enterocyte, and show that the regulation of SLP secretion differs from that of pulmonary surfactant.


Assuntos
Fatores Biológicos/metabolismo , Células CACO-2/metabolismo , Fosfatidilcolinas/metabolismo , Fatores Biológicos/química , Células CACO-2/efeitos dos fármacos , Regulação para Baixo , Humanos , Bicamadas Lipídicas/química , Lipídeos/farmacologia , Lipoproteínas/metabolismo , Fosfatidilcolinas/análise , Poloxâmero/farmacologia , Gravidade Específica , Tensoativos/farmacologia , Fatores de Tempo , Triglicerídeos/metabolismo , Trítio
9.
Biochim Biophys Acta ; 664(2): 380-8, 1981 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-6894702

RESUMO

Organotypic cultures of pulmonary type II epithelial cells were treated with dexamethasone at concentrations between 10(-10) and 10(-5) M for 48 h followed by a 3 h incubation in 5.6 mM [U-14C]glucose. A surfactant and a residual fraction was isolated from the cultures by discontinuous sucrose gradient centrifugation. Phosphatidylcholine and phosphatidylglycerol were purified from each fraction and analyzed for total content. The specific activity of each phospholipid was measured as an index of the rate of synthesis. Dexamethasone treatment produced a dose-dependent increase in synthesis and content of surfactant phosphatidylcholine, with a maximum response occurring at 10(-6) M dexamethasone. At concentrations of 10(-5) M, dexamethasone ceased to produce a significant stimulation. Dexamethasone produced an increase in surfactant phosphatidylglycerol synthesis only at a concentration of 10(-8) M and higher. There was not a significant effect upon the content or rate of synthesis of phosphatidylcholine or phosphatidylglycerol in the residual fraction at any of the dexamethasone concentrations tested.


Assuntos
Dexametasona/farmacologia , Pulmão/metabolismo , Fosfatidilcolinas/biossíntese , Fosfatidilgliceróis/biossíntese , Surfactantes Pulmonares/biossíntese , Animais , Relação Dose-Resposta a Droga , Cinética , Pulmão/efeitos dos fármacos , Pulmão/embriologia , Técnicas de Cultura de Órgãos , Ratos
10.
Biochim Biophys Acta ; 753(1): 6-13, 1983 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-6349697

RESUMO

Organotypic cultures of fetal type II epithelial cells were incubated in media containing insulin at concentrations ranging from 10 to 400 microunits/ml. Exposure to insulin resulted in increased glucose uptake from the media and in the rate of glucose conversion to CO2. Furthermore, both glucose uptake and CO2 production were dependent on the glucose concentration in the media. Surfactant and residual phosphatidylcholine fractions were isolated from the organotypic cultures by sucrose density centrifugation. The presence of low doses of insulin (10-25 microunits/ml) caused a significant increase in the incorporation of glucose into both surfactant and residual phosphatidylcholine. Insulin at levels of 100 microunits/ml or higher resulted in a significant decrease in glucose incorporation into both phosphatidylcholine fractions. Increasing the media glucose concentration from 5.6 to 20 mM caused a 2- to 2.5-fold increase in glucose utilization for surfactant and residual phospholipid synthesis, but did not produce any significant changes in choline incorporation into either surfactant or residual phosphatidylcholine. The addition of 400 microunits/ml of insulin to media containing 20 mM glucose, however, resulted in a 20% decrease in choline incorporation into surfactant phosphatidylcholine but had no effect on choline incorporation into residual phosphatidylcholine. These results suggest that insulin is an important hormone regulating fetal lung maturation and that hyperinsulinemia may be responsible for the delayed lung development in infants of diabetic mothers.


Assuntos
Hiperglicemia/metabolismo , Insulina/farmacologia , Pulmão/metabolismo , Fosfolipídeos/biossíntese , Surfactantes Pulmonares/biossíntese , Animais , Células Cultivadas , Feto , Glucose/metabolismo , Ratos
11.
Biochim Biophys Acta ; 1483(3): 352-62, 2000 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-10666570

RESUMO

The intestinal mucosa metabolizes fatty acids differently when presented to the lumenal or basolateral membrane. Expression of both liver and intestinal fatty acid binding proteins (L- and I-FABPs) uniquely in the enterocyte offers a possible explanation of this phenomenon. An organ explant system was used to analyze the relative binding of fatty acids to each protein. More fatty acid was bound to L-FABP than to I-FABPs (28% vs. 6% of cytosolic radioactivity), no matter on which side the fatty acid was added. However, a 2-3-fold increase in fatty acid binding to the intestinal paralog was noted after apical addition of palmitic or oleic acid in mucosa from chow fed rats. When oleic acid was added apically, a 1.4-fold increase in binding to I-FABP was observed in mucosa derived from chronically fat fed rats, consistent with the previously observed 50% increase in the content of that protein. Immunocytochemical localization of both FABPs in vivo demonstrated an apical cytoplasmic localization in the fasting state, and redistribution to the entire cytoplasm after fat feeding. These data are consistent with the hypothesis that I-FABP may contribute to the metabolic compartmentalization of apically presented fatty acids in the intestine.


Assuntos
Proteínas de Transporte/metabolismo , Ácidos Graxos/metabolismo , Mucosa Intestinal/metabolismo , Proteína P2 de Mielina/metabolismo , Proteínas de Neoplasias , Proteínas do Tecido Nervoso , Animais , Gorduras na Dieta/farmacologia , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Ácidos Graxos/farmacologia , Imunodifusão , Imuno-Histoquímica , Técnicas In Vitro , Fígado/metabolismo , Masculino , Ácido Oleico/metabolismo , Ácido Palmítico/metabolismo , Testes de Precipitina , Ratos , Ratos Sprague-Dawley , Extratos de Tecidos/química
12.
Biochim Biophys Acta ; 1523(1): 49-55, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11099857

RESUMO

The binding of uropathogenic Escherichia coli is mediated at the tips of pili by the PapG adhesin, which recognizes the Galalpha(1-4)Gal disaccharide on the uroepithelial surface. These receptors have been identified unequivocally in the human and murine urinary tracts but not in intestinal epithelium, yet uropathogenic E. coli strains are commonly found in normal colonic microflora. The gastrointestinal tract from duodenum to rectum elaborates a phospholipid-rich membrane particle with surfactant-like properties. In these studies, we report that purified murine particles contain a receptor recognized by the class I PapG adhesin because: (1) PapD-PapG complexes and class I pili bound to surfactant-like particles in a solid-phase assay, whereas binding was not detected in microvillous membranes derived from the same tissues, (2) purified PapD-PapG complex bound to a glycolipid receptor detectable in lipid extracts from the particles, and (3) soluble Galalpha(1-4)Gal inhibited the adhesin by 72% from binding to surfactant-like particles. The Galalpha(1-4)Gal receptor present in the intestinal surfactant-like particle which overlies the intestinal mucosa could provide one means to establish an intestinal habitat for uropathogenic E. coli.


Assuntos
Aderência Bacteriana , Reservatórios de Doenças , Escherichia coli/fisiologia , Proteínas de Fímbrias , Glicolipídeos/fisiologia , Mucosa Intestinal/microbiologia , Infecções Urinárias/microbiologia , Adesinas de Escherichia coli/fisiologia , Animais , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Infecções por Escherichia coli/fisiopatologia , Fímbrias Bacterianas/fisiologia , Humanos , Cinética , Camundongos , Camundongos Endogâmicos A , Urotélio/microbiologia
13.
Diabetes ; 31(Suppl 1 Pt 2): 89-94, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6219019

RESUMO

Although the outcome of pregnancy for women with diabetes mellitus has improved in recent years, the infant of the diabetic mother has an increased risk of major clinical problems, particularly in the early neonatal period. These include birth injury due to macrosomia, neonatal hypoglycemia, respiratory distress syndrome, and serious congenital anomalies. Because of the great difficulties encountered during attempts to investigate these problems in clinical research protocols, there is a continuing need to establish appropriate animal models of the diabetic pregnancy. Studies carried out over the past decade, primarily with chemically-induced diabetes have suggested techniques which might be useful. In general, the choice of the animal to be studied will depend on the hypotheses being addressed. For instance, small animals such as rabbits and rats made diabetic with streptozotocin have been successfully used for investigation of fetal lung development. Furthermore, the rat model has been helpful for evaluation of fetal anomalies associated with maldevelopment of the spine and central nervous system. Larger animals, such as the nonhuman primate, are more appropriate for studying placental function and amniotic fluid composition in diabetic pregnancies. The task group on pregnancy and fetal development recommends that animal models of diabetes mellitus be used for a more extensive hormonal and metabolic characterization of diabetic mothers during pregnancy, for investigation of placental physiology with respect to the transfer of substrates from mother to fetus, for systematic and comprehensive study of mechanisms controlling fetal lung development, and for delineation of the pathophysiology of neonatal hypoglycemia. It is further recommended that animal models of spontaneous diabetes such as the BB/W rat be used in future studies dealing with pregnancy and fetal development. Because females with spontaneous diabetes show reduced conception rates, there is a pressing need to enhance the fertility of these animals in order to intensify studies on fetal development.


Assuntos
Modelos Animais de Doenças , Feto/fisiologia , Gravidez em Diabéticas , Aloxano/farmacologia , Animais , Anormalidades Congênitas/etiologia , Cricetinae , Cricetulus , Diabetes Mellitus Experimental/metabolismo , Feminino , Humanos , Hiperglicemia/fisiopatologia , Hiperinsulinismo/fisiopatologia , Pulmão/embriologia , Macaca mulatta , Placenta/fisiopatologia , Gravidez , Coelhos , Ratos , Estreptozocina/farmacologia , Suínos , Porco Miniatura
14.
J Am Coll Cardiol ; 13(7): 1453-7, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2656820

RESUMO

For 40 years the American College of Cardiology has been a responsible organization in promoting the art and science of cardiac care for people of all ages. This review chronicles the leapfrogging of medical and surgical creativity and contributions to saving lives and making those lives healthy through informed care for people with congenital heart disease.


Assuntos
Procedimentos Cirúrgicos Cardíacos/tendências , Cardiopatias Congênitas/terapia , Cardiopatias Congênitas/história , História do Século XX , Humanos , Estados Unidos
15.
J Am Coll Cardiol ; 3(2 Pt 1): 381-6, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6693626

RESUMO

Comparative evaluation of isometric and dynamic exercise performance in normotensive, borderline hypertensive and hypertensive adolescents was made. Hemodynamic changes were correlated with level of adrenergic sympathetic nervous system activity as measured by plasma epinephrine and norepinephrine values. No significant intergroup differences were found with respect to isometric exercise with the exception of high peak isometric exercise heart rates and plasma epinephrine levels in the patients with significant hypertension. During dynamic treadmill testing, patients with the most marked hypertension demonstrated a statistically significantly greater tachycardia response to exercise that correlated with highest peak exercise epinephrine levels. The most hypertensive systolic dynamic exercise response was evidenced in the borderline hypertensive group in which peak exercise norepinephrine values were significantly higher than in other groups. Maximal exercise serum lactate levels were higher in hypertensive patient groups than in normotensive subjects. Altered hemodynamic response to peak dynamic exercise appears to exist in adolescents with borderline and significant hypertension and is in part mediated by altered activity of the sympathetic nervous system.


Assuntos
Hemodinâmica , Hipertensão/fisiopatologia , Esforço Físico , Sistema Nervoso Simpático/fisiologia , Adolescente , Pressão Sanguínea , Débito Cardíaco , Ecocardiografia , Eletrocardiografia , Epinefrina/sangue , Feminino , Frequência Cardíaca , Humanos , Contração Isométrica , Lactatos/sangue , Ácido Láctico , Masculino , Norepinefrina/sangue
16.
J Am Coll Cardiol ; 23(5): 1245-53, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8144795

RESUMO

OBJECTIVES: The purpose of this study was to determine the involvement in and attitudes toward managed care by cardiovascular specialists and the influence of such programs on their practices. BACKGROUND: No in-depth study has measured the impact of managed care on cardiovascular specialists. Therefore, we conducted a mail survey to determine the prevalence of managed care arrangements among cardiovascular specialists and variations among pediatric and adult cardiologists and cardiovascular surgeons; the types of managed care arrangements in which cardiovascular specialists are engaged; the reasons why those not participating in managed care have chosen not to do so; and the general attitudes among cardiovascular specialists with regard to various aspects of managed care. In addition, we evaluated the impact of managed care among several aspects of cardiovascular practice. METHODS: A questionnaire was mailed in the spring of 1993 to 4,577 practicing, domestic, American College of Cardiology (ACC) members selected at random from within each primary cardiovascular specialty group (adult cardiologists, pediatric cardiologists and cardiovascular surgeons). Additional data concerning practice characteristics were cross tabulated using results from the 1992 ACC membership profile survey. RESULTS: In total, 1,961 of the 4,577 members responded to the survey, representing a 43% response rate. Of all survey respondents, 76% reported entering into at least one relationship with a health maintenance organization (HMO) or preferred provider organization (PPO). Of those not participating in managed care arrangements, the most frequently mentioned reason was "concern over the quality of care." This reason was cited by 51% of those not entering into HMO relationships and 41% of those not participating in PPOs. The majority of respondents indicated that they do not strongly object to the gatekeeper approach to managing nonemergent patients, although more than half indicated concern that gatekeepers may not be appropriate in the management of cardiac emergencies. In addition, cardiovascular specialists report that under managed care, referrals have not increased, income has decreased, and managed care formularies have not substantially affected their ability to prescribe appropriate medication to their patients. CONCLUSIONS: Despite concerns over the quality of care and contract requirements and general philosophical opposition of cardiovascular specialists, most are becoming integrated into managed care environments.


Assuntos
Cardiologia/organização & administração , Sistemas Pré-Pagos de Saúde/estatística & dados numéricos , Organizações de Prestadores Preferenciais/estatística & dados numéricos , Adulto , Atitude do Pessoal de Saúde , Cardiologia/economia , Cardiologia/estatística & dados numéricos , Sistemas Pré-Pagos de Saúde/economia , Sistemas Pré-Pagos de Saúde/normas , Humanos , Pessoa de Meia-Idade , Administração da Prática Médica/estatística & dados numéricos , Organizações de Prestadores Preferenciais/economia , Organizações de Prestadores Preferenciais/normas , Qualidade da Assistência à Saúde , Inquéritos e Questionários , Estados Unidos
17.
J Am Coll Cardiol ; 13(7): 1586-97, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2723271

RESUMO

The cardiac malformations in 41 karyotyped and autopsy cases of trisomy-18 are presented in detail. The salient findings were a ventricular septal defect in all cases; tricuspid valve anomalies in 33 cases (80%); pulmonary valve anomalies in 30 (70%); aortic valve malformations in 28 (68%); mitral valve anomalies in 27 (66%); polyvalvular disease (that is, malformations of more than one valve) in 38 (93%); a subpulmonary infundibulum (conus) in 40 (98%); a bilateral conus with a short subaortic infundibulum in 1 case with double outlet right ventricle (this being the only documented case of bilateral infundibulum in trisomy-18); double outlet right ventricle in 4 cases (10%), three having a subpulmonary infundibulum only and all 4 having mitral atresia; tetralogy of Fallot in 6 cases (15%), 2 having pulmonary atresia; and a striking absence of transposition of the great arteries and inversion at any level (visceral or cardiac), findings that appear to be characteristic of all trisomies. These data suggest that excessive chromosomal material (as in trisomies) may result in situs solitus at all levels. The malformations of the atrioventricular and semilunar valves were characterized by redundant or thick myxomatous leaflets, long chordae tendineae and hypoplastic or absent papillary muscles. The ventricular septal defect was associated with anterosuperior conal septal malalignment in 25 cases (61%). On the basis of the characteristic valvular lesions, the type of ventricular septal defect and the absence of transposition or inversions, two-dimensional echocardiographic diagnosis of trisomy-18 in the fetus may become possible.


Assuntos
Cromossomos Humanos Par 18 , Cardiopatias Congênitas/genética , Trissomia , Feminino , Cardiopatias Congênitas/patologia , Comunicação Interventricular/genética , Comunicação Interventricular/patologia , Valvas Cardíacas/anormalidades , Humanos , Recém-Nascido , Masculino
18.
J Am Coll Cardiol ; 20(2): 366-72, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1634673

RESUMO

OBJECTIVES AND BACKGROUND: Congenital aortic regurgitation is rare as an isolated lesion. We describe seven children with no physical features of the Marfan syndrome in the patients or their families and no other cardiac lesions who had congenital valvular aortic regurgitation. METHODS: From 1954 to the present, seven children with auscultatory and physiologic characteristics of aortic regurgitation were evaluated for a total of 108 patient-years. We report on their natural history, clinical and laboratory findings, management and outcome. RESULTS: In five of the seven children congenital aortic regurgitation was diagnosed in infancy. In four, progressive severity of the regurgitation led to valve replacement at age 3, 10, 15 and 20 years, respectively, and to resection of an aneurysm of the ascending aorta in the 10-year old patient. Two patients had cystic medial necrosis on aortic biopsy. One of these patients died after reoperation for dissecting aneurysm of the thoracic aorta at 22 years of age; the other died after dissection and rupture of the ascending aorta at age 25 years. After obstructing pannus developed, the 3-year old patient underwent replacement of the St. Jude valve at age 10 years. The other three patients were asymptomatic at last follow-up at age 8, 10 and 20 years, respectively. CONCLUSIONS: Supportive management is recommended until it becomes necessary to intervene surgically when regurgitation becomes severe. The need for surgical treatment is indicated by the appearance of a diastolic thrill, left ventricular strain on the electrocardiogram or other evidence of left ventricular dysfunction on the echocardiogram or exercise stress testing by treadmill or radionuclide cineangiocardiography. Close follow-up of these patients is important to detect progression of aortic regurgitation, especially in the presence of cystic medial necrosis.


Assuntos
Insuficiência da Valva Aórtica/congênito , Valva Aórtica , Insuficiência da Valva Aórtica/epidemiologia , Insuficiência da Valva Aórtica/cirurgia , Feminino , Seguimentos , Próteses Valvulares Cardíacas , Humanos , Lactente , Recém-Nascido , Masculino , Síndrome de Marfan/diagnóstico , Reoperação , Fatores de Tempo
19.
Tuberculosis (Edinb) ; 95(4): 415-20, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26022314

RESUMO

RATIONALE: Biomarkers for monitoring response to anti-tuberculosis treatment are needed. We explored immune markers previously published as having predictive capability for 8 week culture status in 39 adults enrolled in a clinical trial in Kampala, Uganda. METHODS: We consecutively selected 20 HIV-negative pulmonary TB subjects with positive cultures, and 19 subjects with negative cultures at the end of intensive phase therapy. At baseline and after 8 weeks, serum was assayed for nine cytokines and soluble cytokine receptors using multiplexed platforms or ELISA. We evaluated their association with week 8 culture status first using single-variable logistic models, then using cross-validated estimates of the C-statistic, a measure of discrimination, of candidate models including 2 or 3 analytes in addition to age. RESULTS: All but one analyte decreased from baseline to week 8 (all p < 0.01). Individual biomarkers were not associated with 8 week culture status. Logistic models including increasing age, higher baseline soluble tumor necrosis factor receptor alpha 1 (sTNF-R1), and higher week 8 C-reactive protein (CRP) concentration classified subjects by culture status with up to 85% accuracy and acceptable discrimination (cross-validated C-statistic 0.76) and calibration (Hosmer-Lemeshow P > 0.2). CONCLUSION: Exploratory post-hoc models including sTNF-R1, CRP, and age, classified 8 week culture status with promising accuracy.


Assuntos
Citocinas/sangue , Mycobacterium tuberculosis/patogenicidade , Receptores de Citocinas/sangue , Tuberculose Pulmonar/diagnóstico , Adulto , Fatores Etários , Antituberculosos/uso terapêutico , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Interações Hospedeiro-Patógeno , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/imunologia , Valor Preditivo dos Testes , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Fatores de Tempo , Resultado do Tratamento , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Uganda , Adulto Jovem
20.
Endocrinology ; 129(1): 270-6, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1711463

RESUMO

Galanin is localized within specific cell types of the rat anterior pituitary gland (AP). Immunocytochemical studies at the light microscope level have shown that lactotrophs, somatotrophs, and thyrotrophs contain galanin in the intact female rat, whereas lactotrophs in the male AP do not. We recently reported that galanin and PRL release from estrogen-treated male and female pituitary cells in culture are coregulated by dopamine, TRH, and somatostatin. This suggested that galanin is stored within secretory granules, conceivably with PRL. Using postembedding immunocytochemistry at the ultrastructural level, the objectives of this study were to: 1) determine the subcellular location of galanin in the AP; 2) elucidate if galanin and PRL are colocalized within the same secretory granules; and 3) compare the cellular localization of galanin in the male and female AP. Male and ovariectomized female (OVEX) Fischer 344 rats were implanted with estradiol-containing or empty Silastic capsules for 2 weeks. Postembedding immunogold labeling was performed using rabbit (for galanin) and guinea pig (for PRL) generated antisera. Two different sizes of colloidal gold spheres were used to localize the hormones in the same tissue section. Galanin was primarily localized in secretory granules of adenohypophyseal cells. Based upon immunocytochemical results and morphological criteria, galanin was contained in somatotrophs but not lactotrophs in the male and OVEX AP. The AP of estrogen-treated rats contained more specific immunogold labeling for galanin than untreated rats. The increased immunoreactivity for galanin was notably associated with lactotrophs. After exposure to estrogen, galanin and PRL were colocalized within the same secretory granules of the male and OVEX pituitary cells. We conclude: 1) galanin is localized within secretory granules of the rat AP; 2) galanin and PRL are colocalized within secretory granules of the male and OVEX AP after estrogen treatment; and 3) galanin is localized in similar cell types in the male and OVEX AP, before and after estrogen treatment. These data provide a morphological basis for the coregulation of galanin and PRL secretion by hypothalamic factors.


Assuntos
Grânulos Citoplasmáticos/química , Estradiol/farmacologia , Peptídeos/análise , Adeno-Hipófise/ultraestrutura , Prolactina/análise , Animais , Grânulos Citoplasmáticos/efeitos dos fármacos , Feminino , Galanina , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Ovariectomia , Adeno-Hipófise/química , Adeno-Hipófise/efeitos dos fármacos , Ratos , Ratos Endogâmicos F344
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