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1.
J Vet Intern Med ; 29(1): 200-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25619515

RESUMO

BACKGROUND: Long-term treatment of cats with ionized hypercalcemia using alendronate has not been evaluated. HYPOTHESIS/OBJECTIVES: Alendronate is well tolerated in treatment of ionized hypercalcemia in cats. ANIMALS: A total of 12 cats with ionized hypercalcemia. METHODS: Prospective study of 12 cats with ionized hypercalcemia of idiopathic origin was identified by telephone and email communication with a convenience sample of consulting veterinarians. Cats were treated with alendronate at a dose of 5-20 mg per feline PO q7d. Serum ionized calcium concentration (iCa) was measured before beginning treatment with alendronate, and after 1, 3, and 6 months of treatment. Alendronate dosage was adjusted according to iCa. Evaluation included physical examination, CBC, biochemistry profile, and diagnostic imaging. The owners and referring veterinarians were questioned about any observed adverse effects. The Wilcoxon matched-pairs signed rank test was used to compare baseline iCa to iCa at different time periods. RESULTS: Alendronate treatment resulted in a decrease in iCa in all 12 cats. The median percentage change in iCa was -13.2%, -15.9%, and -18.1% (range, -29.6 to +7.6; -30.5 to -1.9; -45.8 to +1.5%) at the 1, 3, and 6 month time points, respectively. Baseline iCa was significantly different from 1 month (P = .0042), 3 months (P = .0005), and 6 months (P = .0015). No adverse effects were reported for any of the cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Alendronate was well tolerated and decreased iCa in most cats for the 6-month period of observation.


Assuntos
Alendronato/uso terapêutico , Doenças do Gato/tratamento farmacológico , Hipercalcemia/veterinária , Administração Oral , Alendronato/administração & dosagem , Animais , Cálcio/sangue , Gatos , Esquema de Medicação , Hipercalcemia/tratamento farmacológico
2.
AIDS ; 8(10): 1465-9, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7818818

RESUMO

OBJECTIVE: To describe HIV seroprevalence among non-injecting drug users (non-IDU) entering sentinel drug treatment centers in the United States. DESIGN: Anonymous, blinded (unlinked) HIV seroprevalence surveys. SETTING: Sixty-eight sentinel drug treatment centers in 37 United States metropolitan areas. PARTICIPANTS: Consecutive sample of clients admitted to sentinel drug treatment centers from January 1989 through December 1992. Of 84,617 clients, 37,633 (44.5%) had used illicit drugs but reported no injecting drug use since 1978. MAIN OUTCOME MEASURES: Center-specific, metropolitan area-specific, and national median HIV seroprevalence rates. RESULTS: National median center-specific HIV seroprevalence among non-IDU was 3.2% (range, 0-15.2%). Rates varied widely by geographic area. Median rates were highest in the northeast (5.6%; range, 0-15.2%), intermediate in the south (3.4%; range, 0.6-8.0%), and generally lower throughout the rest of the country: midwest (1.3%; range, 0-3.1%) and west (1.8%; range, 0-14.5%). When stratified by treatment center, there were few statistically significant differences in seroprevalence among African Americans, Hispanics and whites. The median rate was 3.4% among men and 2.7% among women. Rates among non-IDU were lower than among IDU attending the same drug treatment centers, but consistently higher than among heterosexual patients attending sexually transmitted disease clinics in the same metropolitan areas. CONCLUSIONS: HIV seroprevalence among non-IDU entering drug treatment is high in many metropolitan areas. HIV prevention and education efforts in drug treatment centers should target sexual as well as drug-use risk reduction for all clients.


Assuntos
Infecções por HIV/epidemiologia , Soroprevalência de HIV , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adolescente , Adulto , Fatores Etários , Demografia , Etnicidade , Feminino , Geografia , Dependência de Heroína/complicações , Dependência de Heroína/reabilitação , Humanos , Masculino , Metadona/uso terapêutico , Fatores Sexuais , Comportamento Sexual , Transtornos Relacionados ao Uso de Substâncias/complicações , Estados Unidos/epidemiologia , População Urbana
3.
AIDS ; 14(9): 1135-46, 2000 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-10894277

RESUMO

OBJECTIVE: Immune stimulation of CD4 lymphocytes is thought to enhance HIV-1 replication in vivo. Therefore, we sought to define the impact of clinical events identified as putative immune activators on the variability of plasma HIV-1 RNA levels in persons with CD4 cell counts greater than 500 x 10(6) cells/l. DESIGN: We prospectively recorded clinical events and measured plasma HIV-1 RNA levels weekly for 24 weeks in 16 HIV-1-infected adults who were not receiving antiretroviral therapy and who had CD4 cell counts greater than 500 x 10(6) cells/l. METHODS: Standard weekly interviews were conducted to capture potential immune activators (e.g., infections, immunizations, and allergic reactions). All plasma HIV-1 RNA levels were measured using the Amplicor HIV-1 Monitor assay (Roche Diagnostics, Branchburg, New Jersey, USA) according to the manufacturer's instructions. RESULTS: Participants had remarkably stable viral loads during the 6 month study period. Infections were significantly more frequent during the 7 days prior to individual HIV-1 RNA measurements that exceeded the assay variation thresholds determined for this study (+/- 0.324 log) than during the comparable time periods preceding stable measurements (P = 0.023). As a group, the eight participants who had one to four HIV-1 RNA measurements that exceeded the thresholds experienced more infections and declining CD4 cell counts over the study course compared to the eight participants whose measurements all fell within the thresholds (P = 0.058 and 0.053 respectively). CONCLUSIONS: Our study suggests that in untreated HIV-1-infected persons with CD4 cell count greater than 500 x 10(6) cells/l, viral load is generally quite stable, although acute minor infections are associated with transient fluctuations generally lasting no more than 1 week.


Assuntos
Contagem de Linfócito CD4 , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/crescimento & desenvolvimento , RNA Viral/sangue , Síndrome da Imunodeficiência Adquirida/sangue , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/virologia , Adulto , Feminino , Seguimentos , Infecções por HIV/sangue , HIV-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Kit de Reagentes para Diagnóstico , Fatores de Tempo , Carga Viral
4.
AIDS ; 8(11): 1593-8, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7848596

RESUMO

OBJECTIVES: Homeless persons have an increased risk of HIV infection because of a high prevalence of HIV-related risk behaviors. These include drug use, sexual contact with persons at risk for HIV infection, and the exchange of sex for drugs. The objectives of this investigation were to describe HIV seroprevalence rates in homeless adults and runaway youth. METHODS: In 1989, the Centers for Disease Control and Prevention began collaboration with state and local health departments to conduct HIV seroprevalence surveys in homeless populations. Unlinked HIV seroprevalence surveys were conducted in 16 sites; 11 provided medical services primarily to homeless adults, and five to runaway youth aged < 25 years. RESULTS: From January 1989 through December 1992, annual surveys were conducted in 16 sites in 14 cities. Site-specific seroprevalence rates ranged from 0-21.1% (median, 3.3%). Among homeless adults in three sites, rates were higher among men who had sex with other men and those who injected drugs than among persons with other risk exposures (28.9 versus 5.3%). In general, rates were higher for heterosexual men than for women and higher among African Americans than whites. In sites providing services to homeless youth, HIV seroprevalence rates ranged from 0-7.3% (median, 2.3%). CONCLUSIONS: These data indicate that HIV infection among homeless adults and runaway youth is an important public health problem. HIV prevention and treatment should be integrated into comprehensive health and medical programs serving homeless populations.


Assuntos
Infecções por HIV/epidemiologia , Soroprevalência de HIV , Pessoas Mal Alojadas/estatística & dados numéricos , Adolescente , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Fatores Etários , Bissexualidade , Feminino , Hispânico ou Latino/estatística & dados numéricos , Homossexualidade Masculina , Humanos , Masculino , Prevalência , Fatores de Risco , Assunção de Riscos , Comportamento de Esquiva , Estados Unidos/epidemiologia , População Urbana , População Branca/estatística & dados numéricos
5.
AIDS ; 7(4): 483-8, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8507414

RESUMO

OBJECTIVE: The testing of neonatal blood specimens dried on filter paper for maternal HIV antibodies, using an enzyme immunoassay (EIA) with confirmation of repeatedly reactive specimens by immunoblot (IB), was first described in 1987. It has been used to conduct large, unlinked, anonymous HIV seroprevalence surveys for surveillance of HIV in child-bearing women in several countries. We directly assessed the sensitivity and specificity of this combination of tests to detect maternal HIV antibodies. SETTING: Serum samples obtained from mothers delivering at a major hospital in Kinshasa, Zaire were screened for HIV antibody using the rapid assay HIVCHEK. DESIGN: Plasma from HIVCHEK-positive women and age-matched negative controls were tested by enzyme-linked immunosorbent assay (ELISA); repeatedly reactive specimens were confirmed by Western blot (WB). Two days after delivery, whole blood was obtained from each newborn by heel-stick, dried on filter paper, and tested by EIA. Repeatedly reactive specimens were confirmed by IB. MAIN OUTCOME MEASURE: The serologic status of neonatal filter-paper specimens was compared with that of corresponding maternal plasma. RESULTS: The testing of neonatal filter-paper specimens using EIA, with confirmatory testing of repeatedly reactive specimens using IB, was 100.0% sensitive [of the 192 ELISA-positive and WB-positive maternal plasma specimens, 192 of the corresponding newborn filter-paper specimens were EIA-positive and IB-positive; 95% confidence interval (CI), 98.1-100]. The detection of maternal HIV antibodies was 99.6% specific using this combination of tests (of the 281 ELISA-negative or ELISA-positive but WB-negative maternal plasma samples, 280 of the corresponding newborn filter-paper specimens were EIA-negative or EIA-positive but IB-negative; 95% CI, 98.0-100). CONCLUSIONS: Maternal HIV antibodies can be detected accurately by testing neonatal blood dried on filter paper, using EIA with confirmation of repeatedly reactive specimens by IB. This approach can facilitate the determination of HIV seroprevalence in child-bearing women in countries with neonatal screening programs, or where serum or plasma is difficult to obtain.


PIP: Neonatal blood specimens dried on filter paper have been tested for maternal HIV antibodies in large, unlinked, anonymous HIV seroprevalence surveys toward the surveillance of HIV in child-bearing women in several countries. This study assesses the sensitivity and specificity of this combination of tests. The standard approach involves first testing the sample via an enzyme immunoassay (EIA), then confirming repeatedly reactive specimens through immunoblot (IB). To test this methodology, serum samples were obtained from mothers delivering at a major hospital in Kinshasa, Zaire, and screened with rapid assay HIVCHEK for antibody to HIV. Plasma from HIVCHEK-positive women and age-matched negative controls were then subjected to ELISA, with repeatedly reactive samples confirmed with Western blot. Whole blood was later obtained by heel-stick from each newborn 2 days after delivery, dried on filter paper, and tested by EIA and IB for confirmation. The serologic statuses of neonatal filter-paper specimens were then compared with those of corresponding maternal plasma. 100% sensitivity was achieved by testing neonatal filter-paper specimens with EIA and confirming with IB. The combination of tests also proved 99.6% specific for detecting maternal HIV antibodies; both results are at 95% confidence intervals. These results demonstrate that maternal HIV antibodies can therefore be detected accurately by testing neonatal blood dried on filter paper, using EIA, then confirming repeatedly reactive specimens via IB. This approach may help determine HIV seroprevalence in childbearing women in countries with neonatal screening programs or where serum or plasma is difficult to obtain.


Assuntos
Anticorpos Anti-HIV/sangue , Infecções por HIV/imunologia , Troca Materno-Fetal/imunologia , República Democrática do Congo/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/transmissão , Soroprevalência de HIV , Humanos , Técnicas Imunoenzimáticas/estatística & dados numéricos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Sensibilidade e Especificidade
6.
Artigo em Inglês | MEDLINE | ID: mdl-1588489

RESUMO

Estimating the current prevalence of human immunodeficiency virus (HIV) and projecting the future incidence of AIDS require that trends in incidence be analyzed and interpreted. We analyzed AIDS incidence trends in the United States by exposure category and selected demographic factors. In 1987, the trend in United States AIDS incidence changed as growth in the number of cases diagnosed per quarter began to decline. The slowing in growth is due in large part to a plateau in quarterly incidence in men who have sex with men in the New York City, San Francisco, and Los Angeles metropolitan statistical areas (MSAs), and in injecting drug users in the New York City MSA and New Jersey. Incidence has also reached a plateau in both adult/adolescent and pediatric blood and blood product recipients. Quarterly U.S. AIDS incidence was roughly constant during 1990, but appears to have increased to a higher level during the first half of 1991. The variation in incidence trends among subgroups suggests that several factors have affected the trend in total incidence and that the burden of severe symptomatic HIV disease may be shifting.


Assuntos
Síndrome da Imunodeficiência Adquirida/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Previsões , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Fatores de Risco , Estados Unidos/epidemiologia
7.
J Immunol Methods ; 165(1): 31-5, 1993 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-8409466

RESUMO

In a multi-center study, whole blood specimens from 31 HIV-positive and 43 HIV-negative donors were collected in three different anticoagulants and assayed for lymphocyte subsets fresh (within 6 h), and 1 and 2 days later. Each center prepared the specimens by their routine whole blood lysis procedure, labeling with a recommended panel of two-color monoclonal antibody combinations. 1 day (up to about 30 h) after blood collection, the results obtained from blood collected in EDTA (ethylenediamine tetra-acetate), ACD (acid citrate dextrose), and heparin were similar to fresh. Up to 48 h, only ACD and heparin, not EDTA, yielded results similar to fresh specimens. These results were similar for both HIV-positive and -negative specimens.


Assuntos
Coleta de Amostras Sanguíneas/métodos , Ácido Cítrico , Heparina , Imunofenotipagem , Subpopulações de Linfócitos , Anticorpos Monoclonais , Ácido Edético , Citometria de Fluxo , Glucose/análogos & derivados , Soronegatividade para HIV/imunologia , Soropositividade para HIV/imunologia , Humanos , Estudos Multicêntricos como Assunto
8.
J Immunol Methods ; 177(1-2): 43-54, 1994 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-7822837

RESUMO

Enumeration of CD4+ T cells from persons infected with the human immunodeficiency virus (HIV) is important. Traditionally this measurement has been calculated by multiplying the percent of lymphocytes that are CD4+ T cells (from flow cytometry) and the number of lymphocytes per microliter of blood (from hematology measures). Recently, several manufacturers have developed new techniques for determining absolute numbers of CD4+ and CD8+ cells without the need for the flow cytometer and hematology analyzer. We evaluated these methods for accuracy (comparison with traditional methodology) and precision (variability of replicate determinations) as well as for use with specimens older than 1 day. Precision of the assays as determined by the coefficients of variation (CV) from replicates varied from about 3% to about 12%, depending on the assay and the HIV status of the patient. Correlation coefficients of test method results with the standard methodology (r) were all greater than 0.9, and in most cases slopes were close to 1.0 for both CD4 and CD8. Though each methodology will meet different requirements in the laboratory, our results indicate that these assays are all acceptable for enumerating CD4 and CD8 cells in HIV+ as well as HIV- patients.


Assuntos
Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/imunologia , Anticoagulantes , Relação CD4-CD8 , Linfócitos T CD8-Positivos/imunologia , Custos e Análise de Custo , Citometria de Fluxo , Humanos , Imunoensaio/economia , Software , Fatores de Tempo
9.
Biochem Pharmacol ; 62(12): 1597-603, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11755112

RESUMO

Nornicotine is a tobacco alkaloid and an active nicotine metabolite, which accumulates in brain to pharmacologically relevant concentrations following repeated nicotine administration to rats. Furthermore, nornicotine is self-administered by rats, indicating that it has reinforcing efficacy and may contribute to nicotine dependence. Since drugs of abuse activate the mesolimbic dopamine (DA) system to produce rewarding effects, the present study tested the hypothesis that nornicotine evokes DA release from nucleus accumbens in a nicotinic receptor-mediated manner. Rat nucleus accumbens slices were preloaded with [3H]DA and superfused for 60 min in the absence and presence of a range of alkaloid concentrations. Superfusate samples were collected and alkaloid-evoked [3H]overflow was determined. S(-)-Nornicotine (EC(50) value = 3.0 microM), R(+)-nornicotine (EC(50) value = 0.48 microM), and S(-)-nicotine (EC(50) value = 70 nM) evoked [3H]overflow in a concentration-dependent manner. For each nornicotine enantiomer, 0.3 microM was the lowest concentration to evoke significant [3H]overflow. Dihydro-beta-erythroidine (DHbetaE, 10 microM), a classical nicotinic receptor antagonist, inhibited the S(-)-nornicotine-evoked [3H]overflow, indicating the involvement of nicotinic receptors. Furthermore, the effect of S(-)-nornicotine was calcium-dependent, consistent with a nicotinic receptor-mediated mechanism. Whereas S(-)-nornicotine was found previously to be more potent in the striatum, R(+)-nornicotine was more potent than its enantiomer in nucleus accumbens, suggesting the involvement of different nicotinic receptor subtypes in these brain regions. Thus, the results of the current study indicate that nornicotine stimulated DA release from nucleus accumbens in a nicotinic receptor-mediated manner, further supporting the hypothesis that nornicotine contributes to tobacco dependence.


Assuntos
Dopamina/metabolismo , Nicotina/análogos & derivados , Nicotina/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Análise de Variância , Animais , Cálcio/metabolismo , Di-Hidro-beta-Eritroidina/farmacologia , Técnicas In Vitro , Inseticidas/farmacologia , Masculino , Nicotina/metabolismo , Agonistas Nicotínicos/farmacologia , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-Dawley , Fumar/efeitos adversos , Trítio
10.
Psychopharmacology (Berl) ; 162(4): 373-8, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12172690

RESUMO

RATIONALE: Although environmental enrichment renders rats more sensitive to the neurobehavioral effects of acute amphetamine, a previous study found that enriched rats self-administer less amphetamine than isolated rats at a low unit dose (0.03 mg/kg per infusion). In that study, however, acquisition of self-administration was limited to only two amphetamine unit doses using a fixed ratio (FR) schedule. OBJECTIVE: The current study defined the full dose-response relationship for amphetamine self-administration under FR1 and progressive ratio (PR) schedules of reinforcement in rats raised in either an enriched condition (EC) or an isolated condition (IC). METHODS: Rats were raised from 21 to 50 days of age in either an EC or IC environment. Rats were then trained to press a lever for sucrose before implantation of an intravenous jugular catheter. After implantation of the catheter, rats were allowed to acquire stable response patterns under an FR1 or PR schedule of reinforcement before determination of the dose-response function.RESULTS. EC rats self-administered less amphetamine at a low unit dose under both FR1 (0.006 mg/kg per infusion) and PR (0.02 mg/kg per infusion) schedules. However, responding for high unit doses was similar between the two groups. CONCLUSIONS: This result suggests that environmental enrichment may be a protective factor for reducing amphetamine intake at a low dose.


Assuntos
Anfetamina/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Esquema de Reforço , Anfetamina/administração & dosagem , Análise de Variância , Animais , Estimulantes do Sistema Nervoso Central/administração & dosagem , Condicionamento Operante/efeitos dos fármacos , Relação Dose-Resposta a Droga , Meio Ambiente , Infusões Intravenosas , Masculino , Ratos , Ratos Sprague-Dawley , Autoadministração , Sacarose/administração & dosagem
11.
Psychopharmacology (Berl) ; 152(3): 289-94, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11105939

RESUMO

RATIONALE: Nicotine has been shown to be effective as a treatment for reducing tobacco dependence. However, few studies have examined the effect of other nicotinic agonists to determine if they can also decrease nicotine self-administration. OBJECTIVE: The present study determined if nornicotine, a tobacco alkaloid and major nicotine metabolite in brain, could reduce nicotine self-administration in rats. METHODS: Each rat was prepared with an indwelling jugular catheter and trained to self-administer intravenous nicotine (0.03 mg/kg per infusion). After nicotine self-administration stabilized, rats were pretreated with either (-)-nicotine (0, 0.1, 0.3, and 1.0 mg/kg free base) or (+/-)-nornicotine (0, 1, 3, 5.6, and 10.0 mg/kg free base) and assessed for nicotine self-administration. A separate group of rats was maintained on sucrose reinforced responding and pretreated with nornicotine to determine the specificity of the pretreatment effect. In another group of rats, the time course of the pretreatment effect of either (-)-nicotine (0.56 and 1.0 mg/kg) or (+/-)-nornicotine (5.6 and 10.0 mg/kg) was examined. RESULTS: Nicotine and nornicotine each produced a dose-dependent decrease in nicotine self-administration. Furthermore, the decrease in nicotine self-administration in response to the 5.6 mg/kg nornicotine pretreatment was specific to nicotine self-administration, as this dose did not decrease sucrose reinforced responding in tolerant animals. In addition, within the dose range tested, the suppressant effect of nornicotine had a two-fold longer duration than that of nicotine (120 versus 60 min). CONCLUSION: These results suggest that nornicotine may be an effective treatment for tobacco dependence.


Assuntos
Nicotina/análogos & derivados , Nicotina/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Masculino , Nicotina/farmacologia , Ratos , Ratos Sprague-Dawley , Autoadministração
12.
Psychopharmacology (Berl) ; 145(4): 442-51, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10460322

RESUMO

RATIONALE: Nicotine, a tobacco alkaloid, is known to be important in the acquisition and maintenance of tobacco smoking. Nornicotine, an active nicotine metabolite, stimulates nicotinic receptors and may produce psychomotor effects similar to nicotine. OBJECTIVE: The present study determined the effects of acute and repeated administration of nornicotine on locomotor activity and compared its effects with those of nicotine. METHODS: R(+)-Nornicotine (0.3-10 mg/kg), S(-)-nornicotine (0.3-10 mg/kg), S(-)-nicotine (0.1-1 mg/kg) or saline was administered s.c. to rats acutely or repeatedly (eight injections at 48-h intervals). Activity was recorded for 50 min immediately after each injection. RESULTS: S(-)-Nicotine produced transient hypoactivity, followed by dose-related hyperactivity. Repeated S(-)-nicotine administration resulted in tolerance to the hypoactivity and sensitization to the hyperactivity. Subsequent testing following a saline injection revealed evidence of conditioned hyperactivity. Acute administration of 0.3 mg/kg or 1 mg/kg R(+)- or S(-)-nornicotine produced no effect. Transient hypoactivity was observed at 3 mg/kg and 10 mg/kg R(+)-nornicotine and at 10 mg/kg S(-)-nornicotine. However, rebound hyperactivity was not observed following acute administration of either nornicotine enantiomer, suggesting that nornicotine-induced psychomotor effects differ qualitatively from those of S(-)-nicotine. Repeated R(+)-nornicotine resulted in tolerance to the transient hypoactivity, however hyperactivity was not observed. Repeated S(-)-nornicotine resulted in tolerance to the hypoactivity and the appearance of hyperactivity. Repeated administration of either nornicotine enantiomer resulted in a dose-dependent alteration in response to a 1 mg/kg S(-)-nicotine challenge, suggesting some commonalities in the mechanism of action. CONCLUSION: Nornicotine likely contributes to the neuropharmacological effects of nicotine and tobacco use.


Assuntos
Atividade Motora/efeitos dos fármacos , Nicotina/análogos & derivados , Nicotina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Estereoisomerismo
13.
Psychopharmacology (Berl) ; 140(1): 52-6, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9862402

RESUMO

Systemic injection of the sympathomimetic agent ephedrine (EPH) stimulates locomotion in drug-naive rats, an effect that may be dependent on the enantiomer of EPH employed [(-)-EPH or (+)-EPH]. The present experiments examined the effects of repeated EPH exposure on locomotion in rats to assess whether these treatments result in drug tolerance or sensitization. In experiment 1, adult male rats were injected once daily with 0, 10, 20, or 40 mg/kg (-)-EPH (IP) on each of 11 days. Locomotor activity was assessed for 60 min after drug injection. Acute exposure to (-)-EPH treatment increased locomotion for animals receiving 20 or 40 mg/kg, and this effect was augmented after 11 days of drug administration. A vehicle-only injection was given to all animals on day 12 to determine the influence of environmental cues on sensitization. On day 13, all rats were injected with 10 mg/kg cocaine HCl to assess whether repeated (-)-EPH exposure produced a cross-sensitization to cocaine (10 mg/kg, IP). Only rats treated repeatedly with 40 mg/kg (-)-EPH exhibited increases in cocaine-stimulated locomotion relative to saline-treated rats. In experiment 2, repeated exposure to (+)-EPH, 40 mg/kg, but not 20 mg/kg, increased activity and demonstrated the development of sensitization. Cross-sensitization to cocaine (10 mg/kg, IP) was not evident following treatment with either concentration of (+)-EPH. There was no evidence that contextual events alone played a role in the effects observed here.


Assuntos
Comportamento Animal/efeitos dos fármacos , Efedrina/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Cocaína/farmacologia , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Estereoisomerismo
14.
Psychopharmacology (Berl) ; 146(3): 290-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10541729

RESUMO

RATIONALE: Nicotine is a tobacco alkaloid known to be important in the acquisition and maintenance of tobacco smoking. However, other constituents in tobacco may contribute to the dependence liability. OBJECTIVE: The present report sought to determine whether nornicotine, a tobacco alkaloid and metabolite of nicotine, has a reinforcing effect. METHODS: Rats were prepared with a jugular catheter, then were allowed to self-administer intravenously either S(-)-nicotine (0.03 mg/kg/infusion), RS(+/-)-nornicotine (0.3 mg/kg/infusion) or saline using a two-lever operant procedure. The response requirement for each infusion was incremented gradually from a fixed ratio 1 (FR1) to FR5. When responding stabilized on the FR5, other doses of nicotine (0.01 mg/kg/infusion and 0.06 mg/kg/infusion) and nornicotine (0.075, 0.15, and 0.6 mg/kg/infusion) were tested for their ability to control responding. RESULTS: Similar to nicotine, rats self-administered nornicotine significantly above saline control levels. Within the dose ranges tested, both nicotine and nornicotine yielded relatively flat dose-response functions. Extinction of responding was evident when saline was substituted for nornicotine, and responding was reinstated when nornicotine again was available. The rate of nornicotine self-administration was similar between rats tested with either 24-h or 48-h inter-session intervals. CONCLUSION: These results indicate that nornicotine contributes to the dependence liability associated with tobacco use.


Assuntos
Nicotina/análogos & derivados , Animais , Relação Dose-Resposta a Droga , Masculino , Nicotina/administração & dosagem , Ratos , Ratos Sprague-Dawley , Reforço Psicológico , Autoadministração , Estereoisomerismo
15.
Psychopharmacology (Berl) ; 135(2): 133-40, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9497018

RESUMO

The intent of the present study was to determine the effects of systemic injections of the sympathomimetic agent ephedrine (EPH) on extracellular dopamine (DA) levels within the rat nucleus accumbens (NAC) and to compare these effects with those of EPH on locomotion and on feeding. In experiment 1, adult male rats were prepared with an indwelling 3 mm microdialysis probe positioned within the NAC. The rats were injected (i.p.) with vehicle, 5, 10, or 20 mg/kg (-)-EPH with dialysates collected every 20 min for 100 min after drug injection. Systemic injections of 5, 10 or 20 mg/kg (-)-EPH significantly enhanced extracellular levels of NAC DA over baseline by 79%, 130%, and 400%. Systemic injection of 20 mg/kg EPH significantly reduced NAC levels of DOPAC and HVA by 37% and 31%. The effects of EPH on brain dopamine activity were stereospecific given that an additional group of rats injected with 20 mg/kg (+)-EPH exhibited smaller changes in NAC DA (< 25%), DOPAC (< 10%), and HVA levels (< 20%) than did rats injected with 20 mg/kg (-)-EPH. In experiment 2, adult male rats were injected (i.p.) with 0, 5, 10, or 20 mg/kg (-)-EPH prior to placement in automated activity chambers. Total distance traveled was significantly increased by 10 and 20 mg/kg (-)-EPH, but not by 5 mg/kg (-)-EPH. In experiment 3, adult male rats were injected (i.p.) with 0, 2.5, 5, or 10 mg/kg (-)-EPH or with 0, 2.5, 5, or 10 mg/kg (+)-EPH prior to a 30-min feeding test. Although each EPH enantiomer decreased feeding, (-)-EPH was more potent in feeding suppression than was (+)-EPH. The present results suggest that EPH may alter locomotion and feeding via an indirect action on brain dopamine activity.


Assuntos
Dopamina/metabolismo , Efedrina/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Núcleo Accumbens/efeitos dos fármacos , Simpatomiméticos/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Ácido Homovanílico/metabolismo , Masculino , Microdiálise , Núcleo Accumbens/metabolismo , Ratos , Ratos Sprague-Dawley
16.
Neurosci Lett ; 296(2-3): 77-80, 2000 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-11108985

RESUMO

Japanese quail (Coturnix japonica) have been used extensively to study appetitive behaviors. However, little is known about the appetitive-relevant neurochemical systems in this species. The present investigation examined the distribution of D(2)-like dopamine receptors in the quail brain. [(3)H]Spiperone was incubated in brain tissue homogenates and non-specific binding was defined using (-)-sulpiride. Scatchard analysis of whole brain without cerebellum and forebrain alone indicated approximate K(d)'s of 0.08 and 0.04 nM, respectively. In addition, the preferential D(3) agonist (+/-)-2-dipropylamino-7-hydroxy-1,2,3, 4-tetrahydronaphthalene hydrobromide (7-OH-DPAT) did not displace [(3)H]spiperone binding in quail forebrain. Finally, regional analysis showed that the highest densities of D(2)-like receptors were located in the forebrain. Overall, these results indicate that there is some conservation of dopaminergic mechanisms between aves and mammals. Thus, Japanese quail may be useful for examining the neuropharmacological mechanisms of dopaminergic stimulant drugs that work via D(2)-like receptor activation.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Coturnix/metabolismo , Dopamina/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Receptores de Dopamina D2/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Sítios de Ligação/efeitos dos fármacos , Sítios de Ligação/fisiologia , Encéfalo/citologia , Coturnix/anatomia & histologia , Antagonistas de Dopamina/farmacologia , Masculino , Neurônios/citologia , Ensaio Radioligante , Receptores de Dopamina D2/metabolismo , Recompensa , Espiperona/farmacologia , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Transtornos Relacionados ao Uso de Substâncias/patologia , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Tetra-Hidronaftalenos/farmacologia , Trítio
17.
AIDS Educ Prev ; 6(5): 436-45, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7818979

RESUMO

Hemophilia physicians, nurses, and social workers attending a national conference were asked to complete a questionnaire assessing their attitudes and practices regarding HIV risk-reduction counseling. All of the 150 respondents reported recommending the use of condoms to their clients, but only two-thirds felt comfortable demonstrating a condom, while fewer could explain condom choices or how to make safe sex more pleasurable. Less than half questioned their clients about history of STDs, sexual practices, or level of sexual satisfaction. Those who devoted 50 percent or more time to HIV risk-reduction efforts reported being more complete in their assessment and more comfortable in their counseling role. Providers claimed it would help if they had more time (84%) and better skills (64%, especially nurses) for this practice. Because HIV prevention services in hemophilia are delivered by a team, further studies are required to determine the aggregate impact of their intervention on the client.


Assuntos
Atitude do Pessoal de Saúde , Competência Clínica , Infecções por HIV/prevenção & controle , HIV-1 , Pessoal de Saúde/psicologia , Hemofilia A/terapia , Assunção de Riscos , Aconselhamento Sexual , Adolescente , Adulto , Competência Clínica/estatística & dados numéricos , Feminino , Pessoal de Saúde/estatística & dados numéricos , Humanos , Masculino , Relações Enfermeiro-Paciente , Relações Médico-Paciente , Aconselhamento Sexual/estatística & dados numéricos , Inquéritos e Questionários , Estados Unidos
18.
Pharmacol Biochem Behav ; 74(1): 87-94, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12376155

RESUMO

Nornicotine (NORNIC) is a tobacco alkaloid and behaviorally active nicotine metabolite in vivo. Previous behavioral research has shown that NORNIC has locomotor stimulant and reinforcing effects in rats similar to that of nicotine. Results from the current study showed that a bilateral lesion of the nucleus accumbens decreased the locomotor stimulant effect of NORNIC across repeated injections. Pretreatment with the dopamine (DA) D1 receptor antagonist SCH23390 did not block the locomotor stimulant effect of NORNIC or the initiation of sensitization following repeated NORNIC administration. The D2 receptor antagonist eticlopride, however, blocked both the stimulant effect and the initiation of sensitization following repeated NORNIC. Additionally, NORNIC was found to increase synthesis and metabolism of DA, with a greater effect in the mesolimbic pathway compared to the nigrostriatal pathway. Taken together, these results suggest that expression of NORNIC-induced locomotor activity is dependent upon ascending dopaminergic mesolimbic projections, providing additional evidence that NORNIC plays a contributory role in tobacco dependence.


Assuntos
Dopamina/fisiologia , Atividade Motora/efeitos dos fármacos , Nicotina/análogos & derivados , Nicotina/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Benzazepinas/farmacologia , Di-Hidroxifenilalanina/metabolismo , Antagonistas de Dopamina/farmacologia , Sinergismo Farmacológico , Masculino , Núcleo Accumbens/efeitos dos fármacos , Oxidopamina , Ratos , Ratos Sprague-Dawley , Salicilamidas/farmacologia , Estimulação Química , Simpatectomia Química , Simpatolíticos
19.
J Food Prot ; 62(1): 86-90, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9921836

RESUMO

Nine chemical cleaning agents at three concentrations were studied to determine the effect on ATP bioluminescence measurements from pure ATP (PATP) and ATP from chicken exudate (CJATP). The nine commercial cleaning and sanitizing chemicals were concentrated foaming acid (FA), acid sanitizer (AS), iodine cleaner-disinfectant (ZI), alkaline cleaner-degreaser (PC), chlorinated alkaline cleaner (CA), chlorinated sanitizer (CS), quaternary ammonium (QA), antibiofilm agent (AB), and acidic peroxygen sanitizer (HP). Effect was reported as a percent change from the log10 relative light unit (LRLU) measurements of the control groups. All cleaners and sanitizers were tested at one-tenth of the manufacturer's recommended level (MRL), MRL, and two times MRL. FA, PC, and CA at all three concentrations significantly decreased PATP and CJATP LRLU. AS decreased PATP and CJATP LRLU at 200 and 400 ppm quaternary ammonium. ZI decreased PATP LRLU at MRL or greater, while CJATP LRLU were decreased by all concentrations of ZI tested. CS decreased PATP LRLU in a dose-dependent manner; however, for CJATP, LRLU decreased slightly at the two lower concentrations but were not affected by 1,200 ppm CS. QA at MRL or above for PATP or at all concentrations for CJATP significantly increased LRLU. AB decreased LRLU at all concentrations tested for PATP or at MRL or greater for CJATP. HPA at MRL or greater for PATP or at all concentrations for CJATP significantly reduced LRLU. These results demonstrate that commercial sanitizers and cleansers may squelch or increase LRLU measurements when the chemical comes into direct contact with the ATP bioluminescence reagents. Hence, when using ATP bioluminescence as a means of determining sanitary quality of food-processing equipment, it is essential to consider the type and concentration of chemical cleaner or sanitizer being used on the equipment prior to testing.


Assuntos
Trifosfato de Adenosina/metabolismo , Bactérias , Detergentes/farmacologia , Desinfetantes/farmacologia , Manipulação de Alimentos , Medições Luminescentes , Animais , Galinhas/microbiologia , Relação Dose-Resposta a Droga , Hipoclorito de Sódio/farmacologia
20.
J Food Prot ; 61(8): 1013-7, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9713763

RESUMO

Experiments were conducted to determine the effects of sodium hypochlorite (SH), quaternary ammonium (QA), trisodium phosphate (TSP), lactic acid (LA), hydrogen peroxide (HP), and trichlosan (TR) on ATP bioluminescence measurements. Each sanitizer was tested at three different levels and compared to a control group containing no sanitizer. ATP from three sources was analyzed, Escherichia coli, chicken blood, and a pure ATP standard. The effect of each sanitizer was reported as a percent decrease in log10 relative light units (LRLU) for the treatment groups when compared to LRLU from the control groups. SH concentrations of 30, 50, and 70 ppm and quaternary ammonium at concentrations of 10, 20, and 30 ppm had no effect on LRLU measurements, regardless of the ATP source. LA concentrations of 0.5% and higher reduced LRLU by 75%. LRLU measurements were significantly (P < or = 0.05) reduced by approximately 60% when levels of TSP exceeded 1%. HP had no effect on LRLU measurements from any of the ATP sources at 0.1%; however, at 1% HP significantly (P < or = 0.05) decreased LRLU measurements by approximately 60% for all ATP sources. TR at 0.25% had no significant effect on LRLU measurements from any of the ATP sources. TR at 0.5 and 1% reduced LRLU measurements by 30 and 50%, respectively. These results indicate that commercial sanitizers containing LA, TSP, HP, or TR may negatively affect LRLU measurements if the sanitizer is allowed to come into direct contact with the ATP bioluminescence reagents.


Assuntos
Trifosfato de Adenosina/análise , Bactérias , Medições Luminescentes , Saneamento , Peróxido de Hidrogênio/farmacologia , Hipoclorito de Sódio/farmacologia
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