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1.
J Sci Med Sport ; 23(3): 315-319, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31706824

RESUMO

OBJECTIVES: To describe the movement patterns of the Australian Women's Rugby League team during international competition. DESIGN: Retrospective observational study. METHODS: Global Positioning Systems technology recorded the movements of players from the Australian Women's Rugby League team (n=31) during seven international rugby league matches. A subgroup of players (n=18) that played at least 80min in a match were categorized into three positional groups: forwards (n=7), backs (n=7) and halves (n=4), and analysed for external outputs that were classified into multiple speed zones. Mean speed (mmin-1) and mean speed when travelling >12kmh-1 (MS12; mmin-1) were calculated for each 10% interval of playing time of both groups to assess changes in match intensity. RESULTS: Total distance travelled was greater in the first half (3332.9m compared to 3249.0m), along with distances travelled at speeds >15kmh-1 (p<0.05), whereas players travelled further at speeds <6kmh-1 in the second half (p=0.005). Backs travelled further at speeds <6kmh-1 (p=0.002) and >15kmh-1 (p=0.007) compared to forwards. Mean speed significantly reduced across the first and second halves (p<0.05), while MS12 reduced by ∼40% in the first half of the match (i.e. first ∼5min compared to the last ∼5min). CONCLUSION: These results provide coaches with sport-specific activity profiles of female rugby league players that can be used to individualise training prescription. Given that match-intensity deteriorated across the first and second halves, programs may be targeted at improving endurance and supramaximal exercise tolerance in order for female players to withstand high match-demands of international competition.


Assuntos
Desempenho Atlético , Futebol Americano/fisiologia , Movimento , Adulto , Austrália , Feminino , Sistemas de Informação Geográfica , Humanos , Estudos Retrospectivos , Corrida , Adulto Jovem
2.
J Helminthol ; 89(4): 387-97, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24871674

RESUMO

The following account is based on a review lecture given recently at the British Society of Parasitology. We point out that nematode parasites cause very widespread infections of humans, particularly in economically underdeveloped areas where sanitation and hygiene are not adequate. In the absence of adequate clean water and effective vaccines, control and prophylaxis relies on anthelmintic drugs. Widespread use of anthelmintics to control nematode parasites of animals has given rise to the development of resistance and so there is a concern that similar problems will occur in humans if mass drug administration is continued. Recent research on the cholinergic anthelmintic drugs has renewed enthusiasm for the further development of cholinergic anthelmintics. Here we illustrate the use of three parasite nematode models, Ascaris suum, Oesophagostomum dentatum and Brugia malayi, microfluidic techniques and the Xenopus oocyte expression system for testing and examining the effects of cholinergic anthelmintics. We also show how the combination of derquantel, the selective nematode cholinergic antagonist and abamectin produce increased inhibition of the nicotinic acetylcholine receptors on the nematode body muscle. We are optimistic that new compounds and combinations of compounds can limit the effects of drug resistance, allowing anthelmintics to be continued to be used for effective treatment of human and animal helminth parasites.


Assuntos
Anti-Helmínticos/uso terapêutico , Colinérgicos/uso terapêutico , Helmintíase/parasitologia , Animais , Anti-Helmínticos/classificação , Helmintíase/tratamento farmacológico , Humanos , Músculos/efeitos dos fármacos , Nematoides/efeitos dos fármacos
3.
Psychooncology ; 24(1): 1-10, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24953449

RESUMO

OBJECTIVE: This systematic review examined the effectiveness of creative psychological interventions (CPIs) for adult cancer patients. In particular, the findings of randomised controlled trials of art, drama, dance/movement and music therapies on psychological outcomes were examined. METHODS: The review yielded 10 original studies analysing data from a total of 488 patients. Data extraction and quality assessment were conducted by two independent reviewers. RESULTS: Four of the papers focused on the use of art therapy, three studies used music therapy, one paper utilised dance therapy, one study used dance/movement therapy and the remaining paper used creative arts therapies, which was a combination of different art-based therapy approaches. Eight papers focused solely on breast cancer patients, and the remaining studies included mixed cancer sites/stages. The studies reported improvements in anxiety and depression, quality of life, coping, stress, anger and mood. However, few physical benefits of CPIs were reported; there was no significant impact of a CPI on physical aspects of quality of life, vigour-activity or fatigue-inertia or physical functioning. One study was assessed as high quality, seven studies were assessed as satisfactory and two studies were assessed to be of poorer quality. CONCLUSIONS: There is initial evidence that CPIs benefit adult cancer patients with respect to anxiety and depression, quality of life, coping, stress, anger and mood; there was no evidence to suggest that any one type of CPI was especially beneficial. However, more and better quality research needs to be conducted, particularly in the areas of drama and dance/movement therapies.


Assuntos
Ansiedade/terapia , Arteterapia , Dançaterapia , Depressão/terapia , Musicoterapia , Neoplasias/psicologia , Estresse Psicológico/terapia , Adaptação Psicológica , Ansiedade/psicologia , Criatividade , Depressão/psicologia , Humanos , Qualidade de Vida/psicologia , Estresse Psicológico/psicologia , Resultado do Tratamento
4.
Parasitol Int ; 62(6): 616-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23562945

RESUMO

Lymphatic filariasis is a debilitating disease caused by clade III parasites like Brugia malayi and Wuchereria bancrofti. Current recommended treatment regimen for this disease relies on albendazole, ivermectin and diethylcarbamazine, none of which targets the nicotinic acetylcholine receptors in these parasitic nematodes. Our aim therefore has been to develop adult B. malayi for electrophysiological recordings to aid in characterizing the ion channels in this parasite as anthelmintic target sites. In that regard, we recently demonstrated the amenability of adult B. malayi to patch-clamp recordings and presented results on the single-channel properties of nAChR in this nematode. We have built on this by recording whole-cell nAChR currents from adult B. malayi muscle. Acetylcholine, levamisole, pyrantel, bephenium and tribendimidine activated the receptors on B. malayi muscle, producing robust currents ranging from >200 pA to ~1.5 nA. Levamisole completely inhibited motility of the adult B. malayi within 10 min and after 60 min, motility had recovered back to control values.


Assuntos
Anti-Helmínticos/farmacologia , Brugia Malayi/fisiologia , Filariose Linfática/parasitologia , Agonistas Nicotínicos/farmacologia , Técnicas de Patch-Clamp/métodos , Receptores Nicotínicos/fisiologia , Acetilcolina/farmacologia , Animais , Compostos de Befênio/farmacologia , Brugia Malayi/efeitos dos fármacos , Eletrofisiologia , Feminino , Canais Iônicos/efeitos dos fármacos , Canais Iônicos/metabolismo , Levamisol/farmacologia , Células Musculares/efeitos dos fármacos , Células Musculares/fisiologia , Fenilenodiaminas/farmacologia , Pirantel/farmacologia , Receptores Nicotínicos/efeitos dos fármacos
5.
Exp Parasitol ; 132(1): 40-6, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21910990

RESUMO

Nematode parasites infect humans and domestic animals; treatment and prophylaxis require anthelmintic drugs because vaccination and sanitation is limited. Emodepside is a more recently introduced cyclooctadepsipeptide drug that has actions against GI nematodes, lungworm, and microfilaria. It has a novel mode of action which breaks resistance to the classical anthelmintics (benzimidazoles, macrocyclic lactones and cholinergic agonists). Here we review studies on its mode of action which suggest that it acts to inhibit neuronal and muscle activity of nematodes by increasing the opening of calcium-activated potassium (SLO-1) channels.


Assuntos
Anti-Helmínticos/farmacologia , Depsipeptídeos/farmacologia , Canais de Potássio Ativados por Cálcio de Condutância Alta/efeitos dos fármacos , Nematoides/efeitos dos fármacos , Infecções por Nematoides/tratamento farmacológico , Animais , Anti-Helmínticos/uso terapêutico , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Depsipeptídeos/uso terapêutico , Resistência a Medicamentos , Humanos , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Nematoides/metabolismo , Nematoides/fisiologia , Infecções por Nematoides/parasitologia , Infecções por Nematoides/prevenção & controle , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/metabolismo , Neuropeptídeos/metabolismo , Receptores de Peptídeos/efeitos dos fármacos , Receptores de Peptídeos/metabolismo
6.
Br J Pharmacol ; 164(2b): 453-70, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21486286

RESUMO

BACKGROUND AND PURPOSE: Anthelmintics are required for treatment and prophylaxis of nematode parasites of humans and domestic animals. Emodepside, a cyclooctadepsipeptide, is a modern anthelmintic that has a novel mode of action involving a Ca-activated K channel (SLO-1) in Caenorhabditis elegans, sometimes mediated by a latrophilin (LAT) receptor. We examined mechanisms of action of emodepside in a parasitic nematode, Ascaris suum. EXPERIMENTAL APPROACH: RT-PCR was used to investigate expression of slo-1 and lat-1 in A. suum muscle flaps, and two-micropipette current-clamp and voltage-clamp techniques were used to record electrophysiological effects of emodepside. KEY RESULTS: Expression of slo-1 and lat-1 were detected. Emodepside produced a slow time-dependent (20 min), 4-aminopyridine sensitive, concentration-dependent hyperpolarization and increase in voltage-activated K currents. Sodium nitroprusside increased the hyperpolarizations and K currents. N-nitro-L-arginine inhibited the hyperpolarizations and K currents. Phorbol-12-myristate-13 acetate increased the K currents, while staurosporine inhibited the hyperpolarizations and K currents. Iberiotoxin reduced these emodepside K currents. The effect of emodepside was reduced in Ca-free solutions. Emodepside had no effect on voltage-activated Ca currents. CONCLUSIONS AND IMPLICATIONS: Asu-slo-1 and Asu-lat-1 are expressed in adult A. suum muscle flaps and emodepside produces slow activation of voltage-activated Ca-dependent SLO-1-like K channels. The effect of emodepside was enhanced by stimulation of protein kinase C and NO pathways. The data are consistent with a model in which NO, PKC and emodepside signalling pathways are separate and converge on the K channels, or in which emodepside activates NO and PKC signalling pathways to increase opening of the K channels.


Assuntos
Depsipeptídeos/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Canais de Potássio Cálcio-Ativados/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , 4-Aminopiridina/farmacologia , Animais , Anti-Helmínticos/farmacologia , Ascaris suum , Cálcio/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Óxidos de Nitrogênio/metabolismo , Técnicas de Patch-Clamp/métodos , Peptídeos/farmacologia , Canais de Potássio Cálcio-Ativados/antagonistas & inibidores , Canais de Potássio Cálcio-Ativados/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/antagonistas & inibidores , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Proteína Quinase C/metabolismo , Receptores de Peptídeos/antagonistas & inibidores , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Australas Radiol ; 50(5): 475-80, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16981946

RESUMO

We present a retrospective study to evaluate the outcome of postoperative radiotherapy for biochemical or clinical recurrent prostate cancer. Twenty-six patients (median age 60 years) underwent radiotherapy after radical prostatectomy between January 1997 and January 2004. Seven patients received adjuvant radiotherapy and 19 received salvage radiotherapy. The median prostate-specific antigen at diagnosis was 8.6 (0.9-89) and most (23 patients) presented with T(3)N(0) disease. The median follow up was 19.5 months (5-84 months). All patients received a dose of 61.2 Gy at 1.8 Gy per fraction, 20 initially receiving 45 Gy to the lesser pelvis. The median dose to the bladder, rectum and left femoral head were 55.6, 57.5 and 33.8 Gy, respectively. All patients were managed radiotherapeutically by the first author. Twenty-four patients are alive. Two patients have died, one from oesophageal cancer and the second from metastatic prostate cancer. Two other patients also developed metastatic disease. Four asymptomatic patients with a rising prostate-specific antigen are under observation. None of the 26 patients has developed a local recurrence. Seven patients have developed grade 1 late bowel effects and three a grade 2 late effect. Eight patients suffer from grade 1 late genitourinary effects and two from grade 2 effects. One patient developed impotence, whereas 23 patients were rendered impotent postoperatively. There were no grade 3/4 late effects. Postoperative radiotherapy is well tolerated and provides effective local control.


Assuntos
Cuidados Pós-Operatórios/métodos , Prostatectomia , Neoplasias da Próstata/radioterapia , Idoso , Austrália , Relação Dose-Resposta à Radiação , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/radioterapia , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/cirurgia , Doses de Radiação , Estudos Retrospectivos , Terapia de Salvação/métodos , Análise de Sobrevida , Resultado do Tratamento
8.
J Pharmacol Exp Ther ; 288(3): 905-11, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10027825

RESUMO

Cotinine, a major peripheral metabolite of nicotine, has recently been shown to be the most abundant metabolite in rat brain after peripheral nicotine administration. However, little attention has been focused on the contribution of cotinine to the pharmacological effects of nicotine exposure in either animals or humans. The present study determined the concentration-response relationship for (S)-(-)-cotinine-evoked 3H overflow from superfused rat striatal slices preloaded with [3H]dopamine ([3H]DA) and whether this response was mediated by nicotinic receptor stimulation. (S)-(-)-Cotinine (1 microM to 3 mM) evoked 3H overflow from [3H]DA-preloaded rat striatal slices in a concentration-dependent manner with an EC50 value of 30 microM, indicating a lower potency than either (S)-(-)-nicotine or the active nicotine metabolite, (S)-(-)-nornicotine. As reported for (S)-(-)-nicotine and (S)-(-)-nornicotine, desensitization to the effect of (S)-(-)-cotinine was observed. The classic nicotinic receptor antagonists mecamylamine and dihydro-beta-erythroidine inhibited the response to (S)-(-)-cotinine (1-100 microM). Additionally, 3H overflow evoked by (S)-(-)-cotinine (10-1000 microM) was inhibited by superfusion with a low calcium buffer. Interestingly, over the same concentration range, (S)-(-)-cotinine did not inhibit [3H]DA uptake into striatal synaptosomes. These results demonstrate that (S)-(-)-cotinine, a constituent of tobacco products and the major metabolite of nicotine, stimulates nicotinic receptors to evoke the release of DA in a calcium-dependent manner from superfused rat striatal slices. Thus, (S)-(-)-cotinine likely contributes to the neuropharmacological effects of nicotine and tobacco use.


Assuntos
Corpo Estriado/efeitos dos fármacos , Cotinina/farmacologia , Dopamina/metabolismo , Nicotina/metabolismo , Agonistas Nicotínicos/farmacologia , Receptores Nicotínicos/efeitos dos fármacos , Animais , Cálcio/farmacologia , Corpo Estriado/metabolismo , Cotinina/antagonistas & inibidores , Cotinina/metabolismo , Técnicas In Vitro , Masculino , Antagonistas Nicotínicos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Nicotínicos/metabolismo , Sinaptossomos/metabolismo , Trítio
9.
J Pharmacol Exp Ther ; 283(2): 778-87, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9353398

RESUMO

Previous results from our laboratory demonstrated that S(-)nornicotine, a major tobacco alkaloid and an active nicotine metabolite present in the CNS, increases dopamine release from rat striatal slices in a concentration-dependent and calcium-dependent manner. The present study determined if S(-)nornicotine-evoked dopamine release was the result of nicotinic receptor stimulation. Stereoselectivity and the ability of classical noncompetitive and competitive nicotinic receptor antagonists (mecamylamine (MEC) and dihydro-beta-erythroidine (DHbetaE), respectively) to inhibit S(-)nornicotine-evoked [3H]overflow from [3H]dopamine-preloaded rat striatal slices were investigated. Nornicotine increased [3H]overflow in a stereoselective manner at concentrations from 1 to 100 microM. MEC (0.01-100 microM) or DHbetaE (0.01-10 microM) alone did not evoke -3H-overflow. However, 100 microM DHbetaE evoked -3H-overflow, and therefore, was not used in experiments investigating antagonism of S(-)nornicotine's effect. MEC and DHbetaE inhibited S(-)nicotine- (10 microM) evoked [3H]overflow in a concentration-dependent manner. Concentrations of MEC (100 microM) and DHbetaE (10 microM) which maximally inhibited S(-)nicotine's effect were chosen for subsequent experiments determining inhibition of the effect of S(-)nornicotine (0.1 microM-3 mM). MEC and DHbetaE significantly inhibited the effect of low concentrations (<100 microM) of S(-)nornicotine; however, higher concentrations (>100 microM) of S(-)nornicotine were not inhibited by either nicotinic antagonist. Taken together, the results suggest that low concentrations of S(-)nornicotine stimulate nicotinic receptors to evoke the release of dopamine from dopaminergic presynaptic terminals. Thus, nornicotine, which acts as an agonist at neuronal nicotinic receptors, may contribute to the neuropharmacological effects of nicotine and tobacco use.


Assuntos
Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Nicotina/análogos & derivados , Receptores Nicotínicos/fisiologia , Animais , Corpo Estriado/metabolismo , Di-Hidro-beta-Eritroidina/farmacologia , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Mecamilamina/farmacologia , Nicotina/farmacologia , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Trítio
10.
Pharmacol Biochem Behav ; 51(2-3): 397-405, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7667360

RESUMO

Rats were raised from weanling until young adulthood in either an enriched condition (EC) or isolated condition (IC). Following this, the locomotor and rewarding effects of amphetamine were determined using the conditioned place preference (CPP) paradigm. EC rats were more sensitive to the acute locomotor stimulant effect and rewarding effect of amphetamine relative to IC rats. In contrast, EC rats were less sensitive than IC rats to the locomotor sensitization effect obtained across repeated amphetamine injections. To determine the effect of environmental enrichment on alteration of brain dopamine (DA) function induced by amphetamine, the effect of amphetamine on electrically evoked release of DA and dihydroxyphenylacetic acid (DOPAC) was determined in vitro using tissue slices from the nucleus accumbens and striatum of EC and IC rats. No differences between EC and IC rats in release of DA or DOPAC were evident, suggesting that the environmentally induced difference in sensitivity to the behavioral effects of amphetamine involves a neural mechanism extrinsic to the mesolimbic and nigrostriatal terminal field regions.


Assuntos
Anfetamina/farmacologia , Dopamina/metabolismo , Meio Ambiente , Atividade Motora/efeitos dos fármacos , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Condicionamento Operante/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Neostriado/efeitos dos fármacos , Neostriado/metabolismo , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-Dawley
11.
Eur J Pharmacol ; 276(1-2): 195-9, 1995 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-7781690

RESUMO

In addition to S(-)-nicotine, several minor tobacco alkaloids ((+/-)-nornicotine, anabaseine, S(-)-anabasine, and S(-)-N-methylanabasine) are present in tobacco smoke. This study demonstrates that these alkaloids increase fractional 3H release in a concentration-dependent manner from rat striatal slices preloaded with [3H]dopamine, with desensitization of this response. The rank order of EC50 values was S(-)-nicotine (3.0 +/- 2.2 microM) > (+/-)-nornicotine (6.7 +/- 2.1 microM) > anabaseine (15.4 +/- 6.1 microM) = S(-)-N-methylanabasine (16.3 +/- 4.7 microM) = S(-)-anabasine (19.3 +/- 3.2 microM). The alkaloids did not modulate fractional 3H release evoked by electrical-field depolarization. Thus, minor tobacco alkaloids may contribute to the apparent neuroprotective effects of smoking in neurodegenerative diseases.


Assuntos
Anabasina/análogos & derivados , Anabasina/farmacologia , Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Nicotina/análogos & derivados , Animais , Corpo Estriado/metabolismo , Relação Dose-Resposta a Droga , Técnicas In Vitro , Masculino , Nicotina/farmacologia , Ratos , Ratos Sprague-Dawley
12.
J Neurochem ; 60(6): 2167-74, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8492124

RESUMO

The present study demonstrates that S(-)-nornicotine evoked a concentration-dependent increase in dopamine (DA) release from superfused rat striatal slices. The increase in DA release was indicated by an S(-)-nornicotine-induced overflow of endogenous 3,4-dihydroxyphenylacetic acid (DOPAC) in the striatal superfusate and by an S(-)-nornicotine-induced increase in tritium overflow from striatal slices preloaded with [3H]DA. Low concentrations (0.01-1.0 microM) of S(-)-nornicotine, which did not evoke endogenous DOPAC overflow, also were unable to modulate electrically evoked DOPAC overflow. The increase in DOPAC overflow induced by S(-)-nornicotine was compared with that produced by S(-)-nicotine. Comparing equimolar concentrations (0.1-100 microM) of S(-)-nornicotine and S(-)-nicotine, superfusion with S(-)-nornicotine resulted in a significantly greater DOPAC overflow. In contrast to the effect of S(-)-nicotine, S(-)-nornicotine evoked a sustained increase in DOPAC overflow for the entire period of S(-)-nornicotine exposure. Furthermore, DOPAC overflow evoked by S(-)-nornicotine in control Krebs buffer was inhibited by superfusion with a low-calcium buffer. Moreover, in the low-calcium buffer, DOPAC overflow induced by 30 and 100 microM S(-)-nornicotine was not different from that with no S(-)-nicotine, tobacco products and a known metabolite of S(-)-nicotine, increases DA release in a calcium-dependent manner in superfused rat striatal slices. It is interesting that unlike S(-)-nicotine, there does not appear to be desensitization to this effect of S(-)-nornicotine.


Assuntos
Cálcio/farmacologia , Corpo Estriado/metabolismo , Dopamina/metabolismo , Nicotina/análogos & derivados , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Corpo Estriado/efeitos dos fármacos , Relação Dose-Resposta a Droga , Técnicas In Vitro , Cinética , Masculino , Nicotina/farmacologia , Técnica de Diluição de Radioisótopos , Ratos , Ratos Sprague-Dawley , Estereoisomerismo , Trítio
13.
Neuropharmacology ; 31(10): 1033-9, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1436385

RESUMO

Increased release of dopamine (DA) and dihydroxyphenylacetic acid (DOPAC) from slices of striatum of DBA/2J mouse in response to administration of phencyclidine (PCP) in vitro has been observed to be transient, despite continued exposure to PCP. To determine whether this transient response was a result of depletion of releasable pools, toxicity or an adaptive response (desensitization), the recovery of the response to PCP was evaluated. Slices in the control condition were exposed to PCP (300 microM) during test-exposure only. Slices in the PCP pre-exposure condition, were exposed first to PCP (30 microM; pre-exposure) and subsequently to PCP (300 microM; test-exposure). During a washout period (0, 30, 60 or 120 min) between exposures to PCP, the slices were superfused in the absence of PCP. Pre-exposure to PCP diminished the subsequent response to test-exposure to PCP (49 and 37% of control for DA and DOPAC, respectively) after 0 min washout. Overflow of DA evoked by PCP returned towards control values but remained decreased (66% of control) after up to 120 min washout. However, overflow of DOPAC did not return to control values after 60 min washout. Thus, the diminished dopaminergic response, resulting from continued exposure to PCP was not due to depletion of the releasable pool or cytotoxicity but rather to a dynamic adaptive response of the dopaminergic neuron to PCP.


Assuntos
Corpo Estriado/metabolismo , Dopamina/metabolismo , Fenciclidina/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Corpo Estriado/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos DBA , Neurônios/efeitos dos fármacos
14.
J Exp Med ; 175(3): 809-20, 1992 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-1371304

RESUMO

Dissection of the peptide binding grooves of seven subtypes of human histocompatibility leukocyte antigen (HLA)-B27 into the six specificity pockets defined by the 2.6-A structure of HLA-A*0201 revealed just one pocket, the B ("45") pocket, that is conserved among all the HLA-B27 subtypes. Functional studies of mutant HLA-B*2705 molecules with point substitutions in residues of the B pocket show that this structure, and the glutamine residue at position 45 in particular, plays a critical role in cell surface expression, peptide binding, and in the presentation of both exogenous and endogenous peptides by HLA-B*2705. We predict that the B pocket of HLA-B*2705 interacts with an amino acid side chain that anchors peptides in the binding groove, and that this peptide motif is present in most endogenously processed peptides that bind to all seven subtypes of HLA-B27.


Assuntos
Antígeno HLA-B27/química , Antígenos de Histocompatibilidade Classe I/química , Sequência de Aminoácidos , Epitopos , Antígeno HLA-B27/genética , Antígeno HLA-B27/imunologia , Humanos , Dados de Sequência Molecular , Estrutura Molecular , Mutagênese , Mutação , Nucleoproteínas/metabolismo , Orthomyxoviridae/química , Fragmentos de Peptídeos/metabolismo , Polimorfismo Genético , Linfócitos T Citotóxicos/imunologia , Proteínas Virais/metabolismo
15.
Nature ; 345(6270): 41-6, 1990 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-2109837

RESUMO

Adhesion measurements between CD8 and 48 point mutants of HLA-A2.1 show that the CD8 alpha-chain binds to the alpha 3 domain of HLA-A2.1. Three clusters of alpha 3 residues contribute to the binding, with an exposed, negatively charged loop (residues 223-229) playing a dominant role. CD8 binding correlates with cytotoxic T-cell recognition and sensitivity to inhibition by anti-CD8 antibodies. Impaired alloreactive T-cell recognition of an HLA-A2.1 mutant with reduced affinity for CD8 is not restored by functional CD8 binding sites on an antigenically irrelevant class I molecule. Therefore, complexes of CD8 and the T-cell receptor bound to the same class I major histocompatibility complex molecule seem to be necessary for T-cell activation.


Assuntos
Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígeno HLA-A2/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Antígenos CD8 , Linhagem Celular , Antígeno HLA-A2/genética , Humanos , Ativação Linfocitária , Estrutura Molecular , Mutação , Conformação Proteica , Linfócitos T Citotóxicos/imunologia , Transfecção
17.
J Reprod Med ; 17(3): 165-71, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-966242

RESUMO

PIP: 169 married and 42 single women attending the Family Planning Clinic at Wilford Hall U.S. Air Force Medical center were surveyed over a 4-month interval to study changes in sexual drives associated with oral contraceptives (OCs). 74.4% reported they were without side effects. The menstrual flow was decreased in 62% and increased in 4%. Duration of the menstrual cycle was decreased in 57% and unchanged in 41%. 34% indicated less dysmenorrhea while taking OCs. There were some differences between married and single women when questioned about their sexual drive. 68% of the married women and 71% of the single were without change in their libido. 21% of the married women felt that their libido diminished. 22% of single women experienced increased libido. 31% of the single women had a heightened sexual response while only 17% of the married women reported this. Sexual activity increased in 40% of the single women and 16% of the married women. Libido decreased as family size increased. There were only minor differences in changes among those who use different OCs. There was a progressive decrease in libido, sexual response, and sexual activity during the first 2-3 years of medication. After 5 years, however, sexual response was progressively heightened. Fear of pregnancy was uniformly lessened with OCs in 72-75% of all patients. Individuals may have changes in their sexual drives secondary to OCs. However, as many have increased as have decreased drive.^ieng


Assuntos
Anticoncepcionais Orais/efeitos adversos , Libido/efeitos dos fármacos , Comportamento Sexual/efeitos dos fármacos , Feminino , Humanos , Paridade
18.
Am J Obstet Gynecol ; 116(5): 689-93, 1973 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-4713133

RESUMO

PIP: 20 healthy women, age 20-35, participated in a study investigating the effects of a progestogen, quingestanol acetate, on plasma lipids and lipases. These patients had taken no oral contraceptives for at least 6 months. During the treatment period calories were adjusted to maintain weight within a plus or minus 1.5 kg range. The progestogen was administered at 300 mcg/day, beginning on the first evening of a menstrual period. 10 women had follow-up examinations after 1, 3, 6, 9, and 12 months. 10 women had follow-up evaluations only after 1, 3, and 6 months. No change was noted in fasting plasma cholesterol, while fasting plasma triglyceride was unchanged or even slightly lowered. No significant changes were noted in post-heparin lipolytic activity, triglyceride lipase, or monoglyceride hydrolase. Oral contraceptives having only progestational activity may in part sidestep the undesirable changes in lipid metabolism seen with the use of estrogen-progestogen pills.^ieng


Assuntos
Anticoncepcionais Orais/farmacologia , Lipase/sangue , Lipídeos/sangue , Progestinas/farmacologia , Adulto , Colesterol/sangue , Tolerância a Medicamentos , Eletroforese , Esterases/sangue , Feminino , Seguimentos , Glicerídeos , Heparina/sangue , Humanos , Norpregnadienos/administração & dosagem , Norpregnadienos/efeitos adversos , Norpregnadienos/farmacologia , Fatores de Tempo , Triglicerídeos/sangue
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