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1.
JRSM Open ; 9(3): 2054270417739779, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29552344

RESUMO

It is important to consider alternative causes when treating refractory cases of urinary tract infection in the elderly population.

2.
Open Heart ; 3(2): e000463, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27738516

RESUMO

OBJECTIVE: To update the Cochrane review comparing the effects of home-based and supervised centre-based cardiac rehabilitation (CR) on mortality and morbidity, quality of life, and modifiable cardiac risk factors in patients with heart disease. METHODS: Systematic review and meta-analysis. The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO and CINAHL were searched up to October 2014, without language restriction. Randomised trials comparing home-based and centre-based CR programmes in adults with myocardial infarction, angina, heart failure or who had undergone coronary revascularisation were included. RESULTS: 17 studies with 2172 patients were included. No difference was seen between home-based and centre-based CR in terms of: mortality (relative risk (RR) 0.79, 95% CI 0.43 to 1.47); cardiac events; exercise capacity (mean difference (MD) -0.10, -0.29 to 0.08); total cholesterol (MD 0.07 mmol/L, -0.24 to 0.11); low-density lipoprotein cholesterol (MD -0.06 mmol/L, -0.27 to 0.15); triglycerides (MD -0.16 mmol/L, -0.38 to 0.07); systolic blood pressure (MD 0.2 mm Hg, -3.4 to 3.8); smoking (RR 0.98, 0.79 to 1.21); health-related quality of life and healthcare costs. Lower high-density lipoprotein cholesterol (MD -0.07 mmol/L, -0.11 to -0.03, p=0.001) and lower diastolic blood pressure (MD -1.9 mm Hg, -0.8 to -3.0, p=0.009) were observed in centre-based participants. Home-based CR was associated with slightly higher adherence (RR 1.04, 95% CI 1.01 to 1.07). CONCLUSIONS: Home-based and centre-based CR provide similar benefits in terms of clinical and health-related quality of life outcomes at equivalent cost for those with heart failure and following myocardial infarction and revascularisation.

4.
Sex Transm Infect ; 78(6): 464-5, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12473815

RESUMO

An HIV-1 antibody positive black African man with plasma cell variant Castleman's disease and cutaneous Kaposi's sarcoma, despite receiving chemotherapy, had progressive disease. In addition, he developed pain and swelling behind the right knee. Histology of an ultrasound guided biopsy showed Kaposi's sarcoma infiltrating the head of gastrocnemius.


Assuntos
Neoplasias Musculares/patologia , Músculo Esquelético/patologia , Sarcoma de Kaposi/patologia , Neoplasias Cutâneas/patologia , Adulto , Hiperplasia do Linfonodo Gigante/complicações , Infecções por HIV/complicações , Humanos , Joelho , Masculino , Invasividade Neoplásica
5.
Scand J Urol Nephrol ; 36(3): 223-4, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12201940

RESUMO

Benign intratesticular lesions are rare. We describe the second reported case of an intratesticular lipoma and discuss the limitations of ultrasonography in differentiating benign from malignant conditions occurring within the testis.


Assuntos
Lipoma/diagnóstico por imagem , Neoplasias Testiculares/diagnóstico por imagem , Humanos , Lipoma/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Testiculares/patologia , Ultrassonografia
6.
J Trauma ; 48(5): 851-63; discussion 863-4, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10823528

RESUMO

BACKGROUND: Hypotension doubles the adverse outcome of severe brain injury (BI). This finding is thought to be due to secondary ischemia caused by cerebral hypoperfusion. Aggressive prehospital fluid resuscitation in BI is advocated to maintain mean arterial pressure (MAP). Increasing MAP by prehospital fluid resuscitation before control of hemorrhage is thought to increase blood loss and reduce survival. We hypothesized that vasoconstrictor treatment of uncontrolled hemorrhage would increase MAP, reduce hemorrhage volume, and decrease the extent of BI compared with delayed fluid resuscitation (DR) or resuscitation with Ringer's lactate (RL). METHODS: Swine were randomly assigned to a control group or an experimental group: splenic laceration (uncontrolled hemorrhage) and cryogenic BI. The experimental group received one of three prehospital resuscitation regimens: DR, RL, or phenylephrine (Phen) to maintain baseline MAP. Variables were measured at baseline and at 20, 50, and 120 minutes during the simulated "prehospital and early hospital" phases and at 2 and 8 hours after surgical control of the uncontrolled hemorrhage. After killing, biopsies of the brain, liver, kidney, and gut were evaluated for histologic evidence of ischemia and compared between groups. RESULTS: Hemorrhage volume was similar in the experimental groups. Mortality was lowest in the Phen group (11%) compared with DR (40%) and RL (33%) groups. Phen increased MAP and cerebral perfusion pressure. RL infusion increased cerebral blood flow and resulted in less secondary injury than either Phen or DR. CONCLUSION: Phen improves MAP and systemic and cerebral perfusion pressure in the prehospital phase but does not reduce secondary neuronal ischemia. RL restores cerebral blood flow earlier and is associated with less secondary ischemia than either Phen or DR in this model. These data suggest that prehospital infusion of RL in patients with BI and shock is warranted and decreases secondary ischemia.


Assuntos
Agonistas alfa-Adrenérgicos/uso terapêutico , Lesões Encefálicas/tratamento farmacológico , Serviços Médicos de Emergência/métodos , Fenilefrina/uso terapêutico , Ressuscitação/métodos , Choque Hemorrágico/tratamento farmacológico , Vasoconstritores/uso terapêutico , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Biópsia , Pressão Sanguínea/efeitos dos fármacos , Lesões Encefálicas/mortalidade , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Circulação Cerebrovascular/efeitos dos fármacos , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Hidratação/métodos , Soluções Isotônicas/uso terapêutico , Masculino , Fenilefrina/farmacologia , Distribuição Aleatória , Lactato de Ringer , Choque Hemorrágico/mortalidade , Choque Hemorrágico/patologia , Choque Hemorrágico/fisiopatologia , Suínos , Fatores de Tempo , Vasoconstritores/farmacologia
7.
J Infect Dis ; 178(6): 1555-61, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9815203

RESUMO

Thirty-five children <2 years of age mechanically ventilated for respiratory syncytial virus (RSV) infection were randomized to receive an intravenous infusion of 15 mg/kg MEDI-493 or placebo. RSV concentration was measured in tracheal secretions by plaque assay before and at 24-h intervals after treatment. The reduction in tracheal RSV concentration from day 0 to day 1 (-1.7+/-0.28 vs. -0. 6+/-0.21 log10 pfu/mL; P=.004) and from day 0 to day 2 (-2.5+/-0.26 vs. -1.0+/-0.41 log10 pfu/mL; P=.012) was significantly greater in the MEDI-493 group than in the placebo group. RSV concentration in nasal aspirates did not differ significantly between the groups. No significant differences were observed in the tracheal aspirate white blood cell count, or myeloperoxidase or eosinophilic cationic protein concentration, or in measures of disease severity between the groups. Thus, treatment with 15 mg/kg MEDI-493 intravenously was well-tolerated and significantly reduced RSV concentration in tracheal aspirates of children with respiratory failure due to RSV.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Proteína HN , Respiração Artificial , Infecções por Vírus Respiratório Sincicial/terapia , Vírus Sinciciais Respiratórios/isolamento & purificação , Traqueia/virologia , Proteínas Virais/imunologia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Feminino , Humanos , Lactente , Infusões Intravenosas , Intubação , Masculino , Palivizumab , Vírus Sinciciais Respiratórios/fisiologia , Proteínas do Envelope Viral , Proteínas Virais de Fusão/imunologia
8.
Br J Pharmacol ; 124(4): 747-55, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9690867

RESUMO

1. Site-directed mutagenesis was used to create an altered form of the chicken alpha7 nicotinic acetylcholine (ACh) receptor subunit (alpha7x61) in which a leucine residue was inserted between residues Leu9' and Ser10' in transmembrane domain 2. The properties of alpha7x61 receptors are distinct from those of the wild-type receptor. 2. Oocytes expressing wild-type alpha7 receptors responded to 10 microM nicotine with rapid inward currents that desensitized with a time-constant of 710+/-409 ms (mean+/-s.e.mean, n=5). However in alpha7x61 receptors 10 microM nicotine resulted in slower onset inward currents that desensitized with a time-constant of 5684+/-3403 ms (mean+/-s.e.mean, n = 4). No significant difference in the apparent affinity of nicotine or acetylcholine between mutant and wild-type receptors was observed. Dihydro-beta-erythroidine (DHbetaE) acted as an antagonist on both receptors. 3. Molecular modelling of the alpha7x61 receptor channel pore formed by a bundle of M2 alpha-helices suggested that three of the channel lining residues would be altered by the leucine insertion i.e.; Ser10 would be replaced by the leucine insertion, Val13' and Phe14' would be replaced, by Thr and Val, respectively. 4 When present in the LEV-1 nicotinic ACh receptor subunit from Caenorhabditis elegans the same alteration conferred resistance to levamisole anthelmintic drug. Levamisole blocked responses to nicotine of wild-type and alpha7x61 receptors. However, block was more dependent on membrane potential for the alpha7x61 receptors. 5. We conclude that the leucine insertion in transmembrane domain 2 has the unusual effect of slowing desensitization without altering apparent agonist affinity.


Assuntos
Leucina/genética , Mutação , Receptores Nicotínicos/fisiologia , Acetilcolina/farmacologia , Sequência de Aminoácidos , Animais , Anti-Helmínticos/farmacologia , Sequência de Bases , Galinhas , Di-Hidro-beta-Eritroidina/farmacologia , Feminino , Técnicas In Vitro , Leucina/química , Levamisol/farmacologia , Potenciais da Membrana , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Oócitos , Conformação Proteica , Receptores Nicotínicos/química , Receptores Nicotínicos/efeitos dos fármacos , Receptores Nicotínicos/genética , Xenopus laevis
9.
Br J Haematol ; 101(2): 345-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9609533

RESUMO

Primary central nervous system lymphoma (PCNSL), observed among immunocompromised AIDS patients, has not been reported during chemotherapy for acute lymphoblastic leukaemia (ALL). We report a case of PCNSL occurring in a child receiving intensive multiagent chemotherapy for B-cell ALL. In situ hybridization studies demonstrated Epstein-Barr virus genome in both tumours, suggesting a possible link between the two diseases. The clinical response of the PCNSL to conservative therapy highlights the importance of accurately diagnosing such EBV-related disorders, especially in patients where immune compromise can be reversed.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Burkitt/virologia , Neoplasias do Sistema Nervoso Central/virologia , Herpesvirus Humano 4/isolamento & purificação , Linfoma de Burkitt/complicações , Linfoma de Burkitt/tratamento farmacológico , Neoplasias do Sistema Nervoso Central/complicações , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Feminino , Herpesvirus Humano 4/genética , Humanos , Hospedeiro Imunocomprometido , Lactente , Infecções Oportunistas/complicações , RNA Viral/análise
10.
Br J Pharmacol ; 123(3): 518-24, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9504393

RESUMO

1. Imidacloprid is a new insecticide with selective toxicity for insects over vertebrates. Recombinant (alpha4beta2) chicken neuronal nicotinic acetylcholine receptors (AChRs) and a hybrid nicotinic AChR formed by co-expression of a Drosophila melanogaster neuronal alpha subunit (SAD) with the chicken beta2 subunit were heterologously expressed in Xenopus oocytes by nuclear injection of cDNAs. The agonist actions of imidacloprid and other nicotinic AChR ligands ((+)-epibatidine, (-)-nicotine and acetylcholine) were compared on both recombinant nicotinic AChRs by use of two-electrode, voltage-clamp electrophysiology. 2. Imidacloprid alone of the 4 agonists behaved as a partial agonist on the alpha4beta2 receptor; (+)-epibatidine, (-)-nicotine and acetylcholine were all full, or near full, agonists. Imidacloprid was also a partial agonist of the hybrid Drosophila SAD chicken beta2 receptor, as was (-)-nicotine, whereas (+)-epibatidine and acetylcholine were full agonists. 3. The EC50 of imidacloprid was decreased by replacing the chicken alpha4 subunit with the Drosophila SAD alpha subunit. This alpha subunit substitution also resulted in an increase in the EC50 for (+)-epibatidine, (-)-nicotine and acetylcholine. Thus, the Drosophila (SAD) alpha subunit contributes to the greater apparent affinity of imidacloprid for recombinant insect/vertebrate nicotinic AChRs. 4. Imidacloprid acted as a weak antagonist of ACh-mediated responses mediated by SADbeta2 hybrid receptors and as a weak potentiator of ACh responses mediated by alpha4beta2 receptors. This suggests that imidacloprid has complex effects upon these recombinant receptors, determined at least in part by the alpha subunit.


Assuntos
Imidazóis/farmacologia , Inseticidas/farmacologia , Agonistas Nicotínicos/farmacologia , Receptores Nicotínicos/efeitos dos fármacos , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Relação Dose-Resposta a Droga , Drosophila , Potenciais Evocados/efeitos dos fármacos , Feminino , Neonicotinoides , Nicotina/farmacologia , Nitrocompostos , Piridinas/farmacologia , Receptores Nicotínicos/genética , Proteínas Recombinantes/agonistas , Proteínas Recombinantes/genética , Xenopus laevis
11.
Neurosci Lett ; 220(2): 142-6, 1996 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-8981493

RESUMO

An increase in intracellular free calcium concentration ([Ca2+]i) was observed following the application of nicotine to isolated adult dorsal unpaired median (DUM) neurons of the cockroach (Periplaneta americana) terminal abdominal ganglion (TAG) using Fura-2 fluorescence measurements. Bath-applied nicotine (1 mM) induced a transient increase in [Ca2+]i. Calcium responses to bath-applied nicotine were blocked completely by alpha-bungarotoxin (100 nM) and were reduced by 50% in the presence of pirenzepine (1 microM). The sensitivity of the response to both nicotinic and muscarinic antagonists suggested that it was mediated by an acetylcholine receptor with 'mixed' pharmacology. In whole cell current-clamp experiments, nicotine reduced the frequency of evoked action potentials by decreasing the slope of the predepolarization in the last two-thirds of the pacemaker potential. Voltage-clamp studies revealed that nicotine modified the inactivation properties of the maintained low-voltage-activated (LVA) calcium current increasing the rate of relaxation of this current and transforming a U-shaped voltage dependence of inactivation into a monotonic relationship to voltage. These effects were blocked when isolated DUM neurons were pretreated with 0.5 microM alpha-bungarotoxin. Our findings suggested a novel calcium-dependent regulation of firing behavior in TAG DUM neurons following activation of an acetylcholine receptor with 'mixed' pharmacology, resulting in a rise in [Ca2+]i which reduces firing frequency by modulating a maintained LVA calcium current responsible for the action potential predepolarization.


Assuntos
Cálcio/fisiologia , Gânglios dos Invertebrados/fisiologia , Nicotina/farmacologia , Receptores Colinérgicos/fisiologia , Animais , Bungarotoxinas/farmacologia , Condutividade Elétrica , Masculino , Periplaneta , Pirenzepina/farmacologia
12.
J Hosp Infect ; 23(4): 299-304, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8099929

RESUMO

Following an unrelated-donor bone marrow transplant a six-year-old child with severe aplastic anaemia developed Listeria monocytogenes septicaemia and meningitis. Cook-chill foods consumed during his stay in hospital were found to contain strains of L. monocytogenes and other Listeria species. Whole cell protein SDS-PAGE was performed on all isolates. No food isolates were found that were identical to the patient's strain by this technique or by serotyping. The usefulness of whole cell protein SDS electrophoresis for listeria strain differentiation is discussed.


Assuntos
Bacteriemia/etiologia , Transplante de Medula Óssea , Microbiologia de Alimentos , Listeria monocytogenes/isolamento & purificação , Listeriose/etiologia , Meningite por Listeria/etiologia , Anemia Aplástica/cirurgia , Bacteriemia/microbiologia , Proteínas de Bactérias/análise , Técnicas de Tipagem Bacteriana , Criança , Eletroforese em Gel de Poliacrilamida , Humanos , Listeria monocytogenes/classificação , Listeriose/microbiologia , Masculino , Meningite por Listeria/microbiologia
14.
Neuropharmacology ; 31(4): 379-82, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1522955

RESUMO

A series of bisquaternary ammoniums, with chain lengths of between 4-12 carbon atoms (C4-C12), have been tested for their ability to block acetylcholine-induced responses in the fast coxal depressor motor neurone (Df) of the cockroach (Periplaneta americana) and to displace [125I]alpha-bungarotoxin from membrane preparations of the CNS of the cockroach. The physiological studies showed that tetramethonium was inactive, whereas hexa-, octa- and dodecamethonium showed an enhanced ability to block acetylcholine-induced responses as the chain length increased. Decamethonium resulted in a slight increase in acetylcholine-induced depolarizations. Ligand binding studies showed that the ability of the compounds to inhibit the specific binding of [125I]alpha-bungarotoxin increased with size from C4-C12. The results show that neuronal nicotinic receptors in insects differ in aspects of their pharmacology from both the major subclasses of nicotinic receptors of vertebrates.


Assuntos
Compostos de Bis-Trimetilamônio/farmacologia , Baratas/fisiologia , Neurônios Motores/fisiologia , Receptores Nicotínicos/fisiologia , Animais , Bungarotoxinas/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Gânglios/fisiologia , Técnicas In Vitro , Ligantes , Masculino , Neurônios Motores/efeitos dos fármacos , Receptores Nicotínicos/efeitos dos fármacos , Relação Estrutura-Atividade
15.
EMBO J ; 9(13): 4391-8, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1702381

RESUMO

We report the isolation and sequence of a cDNA clone that encodes a locust (Schistocerca gregaria) nervous system nicotinic acetylcholine receptor (AChR) subunit (alpha L1). The calculated molecular weight of the unglycosylated polypeptide, which contains in the proposed extracellular domain two adjacent cysteine residues which are characteristic of alpha (ligand binding) subunits, is 60,641 daltons. Injection into Xenopus oocytes, of RNA synthesized from this clone in vitro, results in expression of functional nicotinic receptors in the oocyte membrane. In these, nicotine opens a cation channel; the receptors are blocked by both alpha-bungarotoxin (alpha-Bgt) and kappa-bungarotoxin (kappa-Bgt). Reversible block of the expressed insect AChR by mecamylamine, d-tubocurarine, tetraethylammonium, bicuculline and strychnine has also been observed. These data are entirely consistent with previously reported electrophysiological studies on in vivo insect nicotinic receptors and also with biochemical studies on an alpha-Bgt affinity purified locust AChR. Thus, a functional receptor exhibiting the characteristic pharmacology of an in vivo insect nicotinic AChR can be expressed in Xenopus oocytes by injection with a single subunit RNA.


Assuntos
DNA/química , Receptores Nicotínicos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Baratas , Drosophila , Gafanhotos/genética , Canais Iônicos/metabolismo , Camundongos , Dados de Sequência Molecular , Músculos/metabolismo , Sistema Nervoso/metabolismo , RNA/biossíntese , Ratos , Homologia de Sequência do Ácido Nucleico , Xenopus laevis
16.
J Hand Surg Am ; 15(4): 552-7, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2380516

RESUMO

Magnetic resonance imaging of seven fresh human cadaveric specimens was used to evaluate the integrity of the triangular fibrocartilage complex of the wrist. A variety of imaging parameters were systematically investigated, including T1-weighted images with and without contrast, long repetition times, short echo time images, and T2-weighted sequences. A variety of imaging planes were also evaluated. Wrist arthrography, dissection, and frozen coronal sections were done to substantiate our interpretations of the magnetic resonance images. T2-weighted images in the coronal plane proved to be of the greatest diagnostic value because the synovial fluid of the joint spaces serves as an excellent endogenous contrast agent. Long repetition time, short echo time sequences could be simultaneously obtained with T2-weighted sequences with the use of a multi-echo pulse sequence to provide an excellent diagnostic package in the future. On the basis of our investigation, the triangular fibrocartilage complex can be consistently and accurately evaluated with magnetic resonance imaging. As magnetic resonance imaging technology improves, wrist probes and suitable magnets should become available that will make the evaluation of triangular fibrocartilage complex abnormalities with magnetic resonance imaging clinically useful.


Assuntos
Cartilagem Articular/anatomia & histologia , Imageamento por Ressonância Magnética , Articulação do Punho/anatomia & histologia , Cartilagem Articular/patologia , Humanos , Articulação do Punho/patologia
17.
Proc R Soc Lond B Biol Sci ; 240(1297): 97-106, 1990 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-1694587

RESUMO

The actions of the polychlorocycloalkane insecticide heptachlor, and its epoxide metabolite, were examined on GABA receptors in insects and vertebrates. Electrophysiological experiments on the cell body of the cockroach (Periplaneta americana) fast coxal depressor motor neuron (Df), and GABA-activated 36Cl- uptake experiments on microsacs prepared from cockroach ventral nerve cords showed that both heptachlor and heptachlor epoxide blocked functional GABA receptors. The block appeared to be non-competitive and was voltage-independent over the membrane potential range -75 mV to -110 mV. There was no significant difference between the potencies of heptachlor and heptachlor epoxide in the functional assays for insect GABA receptors. Both compounds inhibited [35S]-t-butylbicyclophosphorothionate [( 35S]TBPS) binding in insects and vertebrates. The findings provide further evidence for block of an insect GABA receptor/Cl- channel by the cyclodiene class of polychlorocycloalkanes, and reveal differences in the insecticide-[35S]TBPS binding site interactions of insects and vertebrates.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Heptacloro/farmacologia , Receptores de GABA-A/fisiologia , Animais , Ligação Competitiva , Encéfalo/metabolismo , Compostos Bicíclicos com Pontes/metabolismo , Membrana Celular/fisiologia , Canais de Cloreto , Cloretos/metabolismo , Cloretos/fisiologia , Baratas , Eletrofisiologia/métodos , Gânglios/fisiologia , Moscas Domésticas , Canais Iônicos/efeitos dos fármacos , Canais Iônicos/fisiologia , Potenciais da Membrana/efeitos dos fármacos , Proteínas de Membrana/fisiologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Ratos , Receptores de GABA-A/efeitos dos fármacos , Ácido gama-Aminobutírico/farmacologia
18.
Proc R Soc Lond B Biol Sci ; 237(1289): 501-14, 1989 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-2479949

RESUMO

The nitromethylene heterocyclic compound 2(nitromethylene)tetrahydro)1,3-thiazine (NMTHT) inhibits the binding of [125I]alpha-bungarotoxin to membranes prepared from cockroach (Periplaneta americana) nerve cord and fish (Torpedo californica) electric organ. Electrophysiological studies on the cockroach fast coxal depressor motorneuron (Df) reveal a dose-dependent depolarization in response to bath-applied NMTHT. Responses to ionophoretic application of NMTHT onto the cell-body membrane of motorneuron Df are suppressed by bath-applied mecamylamine (1.0 x 10(-4) M) and alpha-bungarotoxin (1.0 x 10(-7) M). These findings, together with the detection of a reversal potential close to that estimated for acetylcholine, provide evidence for an agonist action of this nitromethylene on an insect neuronal nicotinic acetylcholine receptor. The binding of [3H]H12-histrionicotoxin to Torpedo membranes was enhanced in the presence of NMTHT indicating an agonist action at this vertebrate peripheral nicotinic acetylcholine receptor. NMTHT is ineffective in radioligand binding assays for rat brain GABAA receptors, rat brain L-glutamate receptors and insect (Musca domestica) L-glutamate receptors. Partial block of rat brain muscarinic acetylcholine receptors is detected at millimolar concentrations of NMTHT. Thus nitromethylenes appear to exhibit selectivity for acetylcholine receptors and exhibit an agonist action at nicotinic acetylcholine receptors.


Assuntos
Inseticidas/farmacologia , Receptores Colinérgicos/efeitos dos fármacos , Tiazinas/farmacologia , Venenos de Anfíbios/antagonistas & inibidores , Venenos de Anfíbios/metabolismo , Animais , Bungarotoxinas/antagonistas & inibidores , Bungarotoxinas/metabolismo , Antagonistas Colinérgicos , Baratas , Eletrofisiologia/métodos , Glutamatos/metabolismo , Canais Iônicos/fisiologia , Neurônios Motores/fisiologia , Sinapses/fisiologia , Torpedo
19.
Health Soc Work ; 12(1): 5-11, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3643866

RESUMO

Because acquired immune deficiency syndrome (AIDS) has often been perceived as a disease of gay men, little attention has been given to the increasing number of women exposed to AIDS. An overview of the disease reveals that its victims confront both physical and psychosocial problems of great complexity and that social workers have much to contribute to meet the needs of men and women who are affected.


Assuntos
Síndrome da Imunodeficiência Adquirida/psicologia , Síndrome da Imunodeficiência Adquirida/diagnóstico , Síndrome da Imunodeficiência Adquirida/transmissão , Adulto , Anticorpos Antivirais/isolamento & purificação , Emoções , Feminino , HIV/imunologia , Humanos , Risco , Comportamento Sexual , Apoio Social , Serviço Social
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