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1.
Sex Transm Infect ; 85(5): 343-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19204019

RESUMO

OBJECTIVES: Partner concurrency facilitates the transmission of HIV and other sexually transmitted infections (STIs). In this study, we sought to (1) determine the correlates of concurrency among patients with a steady partner, and (2) identify correlates of condom use among patients reporting concurrent steady and non-steady partners. METHODS: Patients recruited from an STI clinic (n = 973; 48% female; 68% African-American) completed a survey that assessed demographic characteristics, substance use, sexual partnerships and sexual behaviour, including condom use. Patients reporting a steady sexual partner for 3 months or longer were included in the analyses. Those who also reported a non-steady partner in the past 3 months, in addition to a steady partner, were considered to have engaged in concurrency. RESULTS: Nearly two-thirds (64%) of patients reported both steady and non-steady partners in the past 3 months. Steady/non-steady concurrency was associated with being male, not cohabitating with a partner, use of alcohol and other drugs, and thinking their steady partner was monogamous. Patients with steady and non-steady partners reported that they seldom used condoms consistently with steady (5%) or non-steady (24%) partners. Compared to patients who did not report concurrency, patients who reported steady/non-steady concurrency reported more episodes of unprotected sex in the past 3 months. Among patients reporting concurrency, consistent condom use with non-steady partners was more likely among individuals who (a) used less alcohol and (b) thought that their steady partner was non-monogamous. CONCLUSIONS: To reduce risk for HIV and other STIs, behavioural interventions need to address partner concurrency and its correlates, including alcohol and other drug use.


Assuntos
Preservativos/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Adolescente , Adulto , Instituições de Assistência Ambulatorial , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , New York/epidemiologia , Fatores de Risco , Sexo Seguro/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Sexo sem Proteção/estatística & dados numéricos , Adulto Jovem
2.
Colorectal Dis ; 10(7): 681-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18215196

RESUMO

OBJECTIVE: This is a prospective study to review the natural history of anorectal dysfunction after primary repair for third or fourth degree obstetric tear and to identify the predictive factors for significant faecal incontinence. METHOD: From January 2003 to December 2005, 121 consecutive women (mean age 29.9 +/- 4.7) who sustained third or fourth degree obstetric tears were assessed. All had primary repair by obstetricians. They were assessed using anorectal physiology testing and endoanal ultrasound. Short-term (3-month postpartum) and medium-term (mean 18.8 +/- 7.7 months) Wexner's continence scores were obtained. RESULTS: Among the 121 women, seven were excluded because of incomplete follow-up. At short-term assessment, 25 out of 114 women were incontinent. One of them underwent another sphincter repair for significant faecal incontinence. Twenty-one and three patients respectively, had mild (Wexner's score 1-4) and moderate (Wexner's score 5-8) symptoms. At medium-term assessment, 24 patients remained incontinent; of these, 20 had mild symptoms (Wexner's score 1-4) and four had moderate incontinence (Wexner's score 5-8). The parity (P = 0.04), degree of obstetric tear (P = 0.036) and short-term Wexner's scores at 3 months postpartum (P < 0.0001) were significantly related to the change in Wexner's scores at medium-term assessment. However, the short-term Wexner's score was the only identifiable predictive factor for significant faecal incontinence. CONCLUSION: Most women suffering from third or fourth degree obstetric tear were continent or mildly incontinent. Poor Wexner's score at short-term assessment at 3 months postpartum was predictive of faecal incontinence in the medium-term.


Assuntos
Canal Anal/lesões , Canal Anal/cirurgia , Episiotomia/efeitos adversos , Incontinência Fecal/etiologia , Incontinência Fecal/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Paridade , Diafragma da Pelve/lesões , Diafragma da Pelve/inervação , Gravidez , Estudos Prospectivos , Fatores de Risco
3.
Am J Psychiatry ; 143(8): 1024-7, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3728717

RESUMO

Psychometric characteristics of the Center for Epidemiological Studies Depression Scale for Children (CES-DC) were evaluated with 148 child and adolescent psychiatric inpatients. Test-retest reliability, internal consistency, and concurrent validity were adequate. Principal components analysis identified three distinct factors: behavioral and cognitive components of depression and a happiness dimension. However, subsequent factor scores and CES-DC total scores were unable to discriminate DSM-III diagnoses, including depressive and nondepressive categories. The CES-DC showed poor reliability and validity in the children alone but had good psychometric properties for the adolescents. More validational research is required before standard clinical use can be recommended.


Assuntos
Transtorno Depressivo/diagnóstico , Inventário de Personalidade , Adolescente , Psiquiatria do Adolescente , Fatores Etários , Criança , Psiquiatria Infantil , Transtorno Depressivo/psicologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Psicometria
4.
J Endocrinol ; 144(2): 311-21, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7706984

RESUMO

The present study examined the association between hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-ovarian axes. HPA activity determined by plasma levels of adrenocorticotropin (ACTH) and corticosterone (B) was assessed in intact female rats as a function of oestrous cycle stage under resting conditions and after exposure to a 20 min restraint stress. To delineate the roles of oestradiol and progesterone in HPA axis modulation, plasma concentrations of ACTH and B were determined in ovariectomised (OVX) animals treated with oestradiol and/or progesterone under resting conditions and during exposure to the stress of a novel environment. The effects of these steroid treatments on the transcription and/or binding properties of the two corticosteroid receptors, the mineralocorticoid (MR) and glucocorticoid (GR) receptors, were also examined in hippocampal tissue, (i) Fluctuations in basal and stress-induced plasma ACTH and B concentrations were found during the oestrous cycle with highest levels at late pro-oestrus. (ii) In OVX steroid-replaced animals, basal and stress-induced activity was enhanced in oestradiol and oestradiol plus progesterone-treated animals compared with OVX controls. (iii) Cytosol binding assays revealed an oestradiol-induced decrease in hippocampal MR capacity. This decrease appears to be due to an effect of the steroid on MR transcription as in situ hybridisation analysis of MR mRNA showed an oestradiol-induced decrease in MR transcript in all hippocampal subfields. (iv) Treatment of oestradiol-primed animals with progesterone reversed the oestradiol-induced decrease in hippocampal MR capacity. Data from MR mRNA hybridisation in situ experiments indicate that this reversal may be due to an antagonism of the oestradiol effect on MR transcription. (v) Progesterone treatment with or without prior oestradiol-priming induced a significant decrease in the apparent binding affinity of hippocampal MR. We show that progesterone and its 11 beta-hydroxylated derivative have a high affinity for the hippocampal MR. (vi) Neither oestradiol nor progesterone affected GR binding parameters in the hippocampus. In conclusion, we find that sex steroids modulate HPA activity and suggest that the observed effects of these steroids on hippocampal MR may underlie their concerted mechanism of action in inducing an enhanced activity at the period of late pro-oestrus.


Assuntos
Estradiol/farmacologia , Estro/fisiologia , Sistema Hipotálamo-Hipofisário/fisiologia , Sistema Hipófise-Suprarrenal/fisiologia , Progesterona/farmacologia , Hormônio Adrenocorticotrópico/sangue , Animais , Corticosterona/sangue , Feminino , Hibridização In Situ , Ovariectomia , Radioimunoensaio , Ratos , Ratos Wistar , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Estresse Fisiológico
5.
Am J Clin Pathol ; 93(4): 555-7, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1690951

RESUMO

In view of the difficulty encountered in distinguishing between 2 degrees renal cell carcinoma (RCC) and hemangioblastoma (HBl) in the central nervous system, the AgNOR technique has been applied empirically to a series of 16 specimens of HBl, 5 primary RCC, and 6 specimens of secondary RCC in the CNS. To avoid tautology, the nature of these was confirmed by immunostaining for epithelial membrane antigen (EMA) and factor VIII-related antigen (FVII RAg). It was found that mean nuclear AgNOR counts in the stromal and endothelial cells of HBl exceeded significantly the counts in the tumor and endothelial cells of RCC, with no overlap in values. It is suggested that the AgNOR method is a useful adjunct in achieving the differential diagnosis of HBl and RCC in the nervous system.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Cerebelares/patologia , Hemangiossarcoma/patologia , Neoplasias Renais/patologia , Região Organizadora do Nucléolo/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/diagnóstico , Neoplasias Cerebelares/diagnóstico , Feminino , Hemangiossarcoma/diagnóstico , Humanos , Imuno-Histoquímica , Neoplasias Renais/diagnóstico , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/análise , Nitrato de Prata , Neoplasias da Medula Espinal/diagnóstico , Neoplasias da Medula Espinal/patologia , Coloração e Rotulagem/métodos
6.
Psychopharmacology (Berl) ; 111(2): 244-50, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7870959

RESUMO

The anxiogenic nature of the interoceptive discriminative stimulus induced by pentylenetetrazole (PTZ) was investigated by examining the discriminatory behaviour of PTZ conditioned pigs during a conditioned emotional response (CER). A CER was induced in a nonoperant situation, by pairing a tone stimulus with the application of a mild, non-injurious electric shock. Subsequent presentation of the conditioned tone stimulus alone produced a generalisation to the PTZ cue. This generalisation of the conditioned emotional state (CES) to the PTZ cue was antagonised by pretreatment with diazepam (0.5 mg/kg, PO; 30 min). The PTZ stimulus was also antagonised by diazepam (0.5 mg/kg, PO; 30 min) but not by an anticonvulsant dose of ethosuximide (30 mg/kg, PO; 1-3 h), providing further confirmation of the anxiogenic nature of the PTZ cue. Our results demonstrate the validity of the PTZ discrimination paradigm in pigs as a test of anxiety.


Assuntos
Comportamento Animal/efeitos dos fármacos , Discriminação Psicológica/efeitos dos fármacos , Pentilenotetrazol/farmacologia , Animais , Condicionamento Operante/efeitos dos fármacos , Sinais (Psicologia) , Diazepam/farmacologia , Eletrochoque , Emoções/efeitos dos fármacos , Etossuximida/farmacologia , Masculino , Esquema de Reforço , Suínos
7.
J Steroid Biochem Mol Biol ; 50(3-4): 213-7, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8049152

RESUMO

Incubation of whole mouse brain homogenate with [3H]progesterone resulted in two metabolites: the 5 alpha-reduced product, 5 alpha-pregnane-3,20-dione and another metabolite at a 3-fold greater yield. This differed from rat brain, which produced predominantly the 5 alpha-reduced metabolite under the same conditions. Subcellular fractionation of mouse brain demonstrated a particulate location for the 5 alpha-reduction of progesterone and a cytosolic location for the production of the unknown major metabolite. Treatment of this unknown metabolite with chromium trioxide resulted in a reconversion to progesterone, indicating the presence of a hydroxyl at position 3 or 20. Comparison of the chromatographic behaviour of the unknown metabolite with that of authentic progesterone derivatives suggested that this metabolite corresponds to 20-hydroxy-4-pregnene-3-one.


Assuntos
Encéfalo/metabolismo , Progesterona/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , Progestinas/metabolismo
8.
J Steroid Biochem Mol Biol ; 47(1-6): 183-90, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8274434

RESUMO

Mineralocorticoid receptors (MRs) in neurons of the anterior hypothalamus and the periventricular brain regions mediate aldosterone-selective actions on sodium homeostasis, salt appetite and cardiovascular regulation. Corticosterone is not effective in these neurons, possibly because it is enzymatically inactivated. However, MRs in limbic brain regions, notably in the hippocampal neurons, do already respond to very low concentrations of both corticosterone and aldosterone. The MR-mediated effects stabilize neuronal transmission and appear critical for neuronal integrity of a sub-region of the hippocampus: the dentate gyrus. Higher concentrations of corticosterone induced by stress and the circadian rise progressively activate the lower affinity glucocorticoid receptors (GRs), which in coordination with MR-mediated actions then facilitate adaptive processes required for recovery of homeostasis. It is postulated that this balanced MR- and GR-mediated action of corticosterone is of critical importance for regulation of the stress response and behavioural adaptation.


Assuntos
Encéfalo/fisiologia , Receptores de Mineralocorticoides/fisiologia , Aldosterona/farmacologia , Aldosterona/fisiologia , Animais , Comportamento Animal/fisiologia , Hipocampo/fisiologia , Homeostase , Neurônios/fisiologia , Núcleos da Rafe/fisiologia , Sódio/metabolismo
9.
Virchows Arch ; 425(2): 195-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7952503

RESUMO

Investigation of the smaller of a pair of unequal kidneys showed a band of atrophy in the inner medulla, sparing the papillary tip, which was viable and contained collecting ducts. The kidney had extensive cortical atrophy with glomerulocystic disease and multiple tiny renal cell neoplasms. These changes were considered secondary to the medullary lesion. Study of 85 other kidneys taken a autopsy and surgery showed 8 other cases with similar band-like atrophy in the medulla to various degrees. All 9 cases had severe vascular disease. This asymmetrical or band-like atrophy of the renal medulla seemed to be fairly common but previously unreported, could be differentiated from renal papillary necrosis, and was most likely due to an episode of severe ischaemia, possibly in kidneys with pre-existing vascular narrowing.


Assuntos
Rim/patologia , Adulto , Idoso , Atrofia/etiologia , Atrofia/patologia , Feminino , Humanos , Isquemia/complicações , Isquemia/patologia , Rim/irrigação sanguínea , Medula Renal/patologia , Neoplasias Renais/patologia , Transplante de Rim/patologia , Masculino , Pessoa de Meia-Idade
10.
J Clin Pathol ; 39(4): 366-70, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3517071

RESUMO

Two cases of Strongyloides stercoralis hyperinfestation syndrome accompanied by Gram negative bacteraemia and meningitis were studied. Both occurred in non-immunosuppressed West Indian women.


Assuntos
Infecções por Escherichia coli/complicações , Meningite/complicações , Estrongiloidíase/complicações , Adulto , Idoso , Encéfalo/patologia , Feminino , Humanos , Intestinos/parasitologia , Larva , Meningite/patologia , Strongyloides/isolamento & purificação , Estrongiloidíase/parasitologia , Estrongiloidíase/patologia
11.
J Clin Pathol ; 44(11): 909-14, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1752981

RESUMO

Five cases of central pontine myelinolysis (CPM) were detected by neuropathological examination in a series of 50 patients coming to necropsy after liver transplantation. One patient also had extrapontine myelinolysis. In no case was the diagnosis made during life. Only two patients showed rapid rises in serum sodium concentrations. The incidence of hyponatraemia, before and after transplantation, and rapid rises in serum sodium in patients with CPM was significantly greater than in the 45 patients showing no neuropathological evidence of CPM. It is concluded that there is a high incidence of CPM after liver transplantation, that clinical diagnosis is difficult, and that there is no simple direct correlation between rapid serum sodium changes and the development of this condition. Avoidance of major electrolyte fluctuations at the time of liver transplantation is recommended but it must be emphasised that CPM may occur without any rapid rise in serum sodium concentration.


Assuntos
Doenças Desmielinizantes/patologia , Transplante de Fígado , Ponte/patologia , Adolescente , Adulto , Encefalopatias/etiologia , Encefalopatias/patologia , Criança , Doenças Desmielinizantes/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Sódio/sangue
12.
Obstet Gynecol ; 94(5 Pt 2): 883-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10546778

RESUMO

OBJECTIVE: To review the frequency of lower urinary tract injuries after major gynecologic surgery and the role of routine intraoperative cystoscopy during major gynecologic surgery in the detection of lower urinary tract injuries. DATA SOURCES: We combined a MEDLINE search for reports from 1966 to October 1998, using the terms "urinary tract injury," "ureter/ureteric/ureteral obstruction/fistula/injury," "bladder fistula/injury," and "vesico-vaginal fistula," with a second search for all reports of gynecologic surgical procedures. Additional references were obtained from relevant articles and review articles. METHODS OF STUDY SELECTION: Included were all English language articles on the frequency of unintentional urinary tract injuries identified during or after benign gynecologic surgery. There were 22 reports on the frequency of lower urinary tract injuries after gynecologic surgery and eight on the use of routine cystoscopy during gynecologic surgery to diagnose unsuspected injuries. TABULATION, INTEGRATION, AND RESULTS: In the reports of studies not involving routine cystoscopy, the frequency of ureteral injury varied from 0 to 14.6 injuries per 1000 operations, with an overall frequency of 1.6 per 1000. The frequency of bladder injury varied from 0.2 to 19.5 per 1000, with an overall frequency of 2.6 per 1000. Only 11.5% of ureteral injuries and 51.6% of bladder injuries were identified and managed intraoperatively. In the reports of studies involving routine cystoscopy, the frequency of ureteral injury varied from 0 to 26.8 per 1000, with an overall frequency of 6.2 per 1000. The frequency of bladder injury varied from 0 to 29.2 per 1000, with an overall frequency of 10.4 per 1000. Up to 90% of unsuspected ureteral injuries and 85% of unsuspected bladder injuries were identified with the use of cystoscopy and were managed successfully intraoperatively. In 69% of the unsuspected ureteral and bladder injuries, the intraoperative management consisted of removing and replacing sutures or repairing unintentional cystotomies. CONCLUSION: Use of routine intraoperative cystoscopy during major gynecologic and urogynecologic surgery might prevent sequelae from lower urinary tract injuries.


Assuntos
Cistoscopia , Doenças dos Genitais Femininos/cirurgia , Complicações Intraoperatórias/diagnóstico , Ureter/lesões , Bexiga Urinária/lesões , Feminino , Humanos , Complicações Intraoperatórias/epidemiologia
13.
Obstet Gynecol ; 97(6): 1010-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11393196

RESUMO

OBJECTIVE: Vaginal hysterectomy remains the accepted surgical treatment for women with uterine prolapse. The Manchester repair is favored in women wishing uterine preservation. Vaginal hysterectomy alone fails to address the pathologic cause of the uterine prolapse. The Manchester repair has a high failure rate and may cause difficulty sampling the cervix and uterus in the future. The laparoscopic suture hysteropexy offers physiologic repair of uterine prolapse. METHOD: At the laparoscopic suture hysteropexy, the pouch of Douglas is closed and the uterosacral ligaments are plicated and reattached to the cervix. RESULTS: Forty-three women with symptomatic uterine prolapse were prospectively evaluated and underwent laparoscopic suture hysteropexy with a mean follow-up of 12 +/- 7 months (range 6-32). The mean operating time for the laparoscopic suture hysteropexy alone was 42 +/- 15 minutes (range 22-121), and the mean blood loss was less than 50 mL. On review, 35 women (81%) had no symptoms of prolapse and 34 (79%) had no objective evidence of uterine prolapse. Two women subsequently completed term pregnancies and were without prolapse. Both underwent elective cesarean delivery. CONCLUSION: The laparoscopic suture hysteropexy is effective and safe in the management of symptomatic uterine prolapse. The result is physiologically correct, without disfiguring the cervix. This may be an appropriate procedure for women with uterine prolapse wishing uterine preservation.


Assuntos
Laparoscopia/métodos , Técnicas de Sutura , Prolapso Uterino/cirurgia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Histeroscopia/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Prolapso Uterino/diagnóstico
14.
Obstet Gynecol ; 98(1): 40-4, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11430954

RESUMO

OBJECTIVE: To compare iliococcygeus (prespinous) and sacrospinous fixation for vaginal vault prolapse. METHODS: Between 1994 and 1998, 78 women underwent sacrospinous colpopexy and 50 underwent iliococcygeus fixation for the management of symptomatic vaginal vault prolapse. A matched case-control study was designed to compare the two approaches. The matched variables included age, parity, body mass index, degree of vault prolapse, menopause, sexual activity, constipation, previous prolapse or continence surgery, stress incontinence, and length of review. Thirty-six matched pairs were isolated, resulting in a study with a power of 50% to detect a 20% difference in the success rates between the two groups. RESULTS: The subjective success rate for the iliococcygeus group was 91%; it was 94% for the sacrospinous group (P =.73). The objective success rate was 53% and 67% (P =.36), and the patient satisfaction with surgery was 78 of 100 and 91 of 100 (P =.01) on a visual analogue scale. The mean length of postoperative follow-up was 21 months for the iliococcygeus group and 19 months for the sacrospinous group (P =.52). The recovery time was 54 days in the iliococcygeus group and 39 days in the sacrospinous group (P =.04). No significant difference was seen in the incidence of postoperative cystoceles or damage to the pudendal neurovascular bundle. CONCLUSION: Sacrospinous and iliococcygeus fixation are equally effective procedures for vaginal vault prolapse and have similar rates of postoperative cystocele, buttock pain, and hemorrhage requiring transfusion. The sacrospinous ligament fixation should not be discarded in favor of the iliococcygeus fixation in the management of vaginal vault prolapse.


Assuntos
Prolapso Uterino/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Seguimentos , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Ligamentos , Pessoa de Meia-Idade
15.
J Neurosci Methods ; 43(1): 69-76, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1528074

RESUMO

Using a novel pharmacological conditioning procedure, pigs were conditioned to discriminate the effects of a subconvulsant dose of the anxiogenic drug pentylenetetrazole (PTZ; 2.8-10 mg/kg, i.v.) from saline. The operant chamber provided two levers at which pigs were trained to press at a fixed ratio of 20 presses per food reward (FR 20). The animals were conditioned to select both levers alternately following saline treatment and to select one lever only following PTZ treatment. This procedure enabled the onset and offset of the PTZ stimulus to be detected within single test sessions; infusion of PTZ to animals already selecting both levers alternately after a saline pretreatment induced a period of response exclusive to the PTZ lever followed by a return to an alternation of lever selection response. The ability of the novel procedure to detect the time course of the drug cue should improve future evaluations of the psychological states induced by centrally acting drugs. With PTZ as the training drug, the novel procedure presents a valuable means to study the neurobiology of anxiety.


Assuntos
Aprendizagem por Discriminação/fisiologia , Pentilenotetrazol/farmacologia , Animais , Ansiedade/induzido quimicamente , Ansiedade/psicologia , Sinais (Psicologia) , Aprendizagem por Discriminação/efeitos dos fármacos , Modelos Animais de Doenças , Masculino , Esquema de Reforço , Suínos
16.
Behav Brain Res ; 94(1): 173-85, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9708848

RESUMO

The distribution of dopamine (DA) D-1 and D-2 receptors has been studied by autoradiography in the anterior forebrain of the pre-hypertensive spontaneously hypertensive rat (SHR) as an animal model of attention-deficit hyperactivity disorder (ADHD) in children. Juvenile male SHR and Wistar Kyoto (WKY) controls were given either vehicle or the DA re-uptake blocker methylphenidate (MP; 3 mg/kg, i.p.), daily during a 2-week period. A saturation analysis for the D-1 receptor subfamily was carried out with 0.1-5.0 nM of [3H]SCH23390 and two competition studies for the D-2 receptor subfamily with 4 nM of [3H]raclopride or 5 nM of [3H]quinpirole were carried out with unlabelled spiperone and 7-OH-DPAT as unlabelled displacers on cryostat coronal sections of the anterior forebrain. Quantitative receptor autoradiography and computer-assisted image analysis with reference to co-exposed 3H-microscale standards showed in vehicle-treated SHR higher density of DA D-1/D-5 receptor subtypes in the caudate-putamen (CPU), the nucleus accumbens (ACB) core and shell and the olfactory tubercle (OT), which was associated to a lower affinity. MP treatment normalised the DA D-1/D-5 receptors by decreasing the number of binding sites and increasing the affinity to control level. In addition, MP treatment 'down-regulated' DA D-2/D-4 subtypes in the CPU, ACB and OT, and 'up-regulated' mostly D-3 subtype in CPU, ACB, OT in both rat lines and in the globus pallidus, ventral pallidum and lateral septum in WKY rats only. In contrast, D-3 receptors were 'down-regulated' in the islands of Calleja in both rat lines. Moreover, regional cross-correlative analyses revealed a modulatory influence of DA receptors in the cross-talk within the anterior forebrain, which was altered in the SHR. Thus, the differential distribution and regulation of DA receptor subtypes following DA re-uptake blocker as well as the different regional cross-talk in the target sites of nigrostriatal and mesolimbic DA systems lend support to the DA hypothesis of ADHD in children.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Sistema Límbico/fisiopatologia , Mesencéfalo/fisiopatologia , Plasticidade Neuronal/fisiologia , Receptores de Dopamina D1/fisiologia , Receptores de Dopamina D2/fisiologia , Animais , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Autorradiografia , Mapeamento Encefálico , Modelos Animais de Doenças , Sistema Límbico/patologia , Masculino , Mesencéfalo/patologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptor Cross-Talk/fisiologia
17.
Behav Brain Res ; 130(1-2): 171-9, 2002 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-11864732

RESUMO

Functional molecular neuroimaging techniques have been applied to the study of the neural substrates of Attention-Deficit Hyperactivity Disorder (ADHD) in an animal model, the juvenile SHR rat. They include quantitative receptor autoradiography and immunocytochemistry for neuronal markers such as Ca2+/Calmodulin Dependent Kinase II (CaMKII) and transcription factors. Multiple evidence emerges for a rostro caudal dissociation within the dorsal (DS) and ventral striatum (VS) (n. accumbens) and olfactory tubercle (OT). It consists in (i) a higher density of dopamine (DA) D-1/D-5 receptor binding sites in a discrete segment of the anterior forebrain that comprises the DS, VS and OT, (ii) a lower density of DA D-2/D-3 autoreceptors in the caudal portion of the n. accumbens shell subterritory, (iii) a reduced number of CaMKII and c-FOS positive elements only in the anterior portion of DS and VS (iv) reversal by repeated injections of methylphenidate (MP) (3 mg/kg, 14 days) with 'downregulation' in SHR and 'up-regulation' in the WKY control rats of DS and VS of DA D-1/D-5 receptors. Thus, under basal conditions the mesocorticolimbic (MCL) DA system appears to be hyperfunctioning rather than hypofunctioning, as demonstrated (i) by subsensitivity of presynaptic D-3 autoreceptors and (ii) by phasic inhibition of MCL activity induced by acute blockade of endocannabinoid reuptake using AM404. Following MP treatment, the hyperfunctioning MCL DA system turns into a hypofunctioning one, as earlier suggested by Solanto. Since the target neurons of MCL fibers seem to be uncoupled to D-1 receptors, the medium spiny GABA neurons projecting to the ventral pallidum and ventral tegmental area (VTA) exert a weak feedback inhibition on the neurons of origin of MCL system. Therefore, MCL neurons maintain a high basal activity with consequences on the cortico-striato-pallido-thalamo-cortical system and amygdala complex through the 'extended amygdala system'. While the former explains the attention, motivation and activity alterations of this rat model of ADHD, the latter explains the emotional symptoms of the syndrome. It remains to be ascertained the starting point in the network leading eventually to the segmental defect as well as its significance in humans.


Assuntos
Córtex Cerebral/fisiologia , Sistema Límbico/fisiologia , Neostriado/fisiologia , Animais , Autorradiografia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Moduladores de Receptores de Canabinoides , Dopamina/fisiologia , Imuno-Histoquímica , Perfusão , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptores de Dopamina D1/fisiologia , Receptores de Dopamina D2/fisiologia , Fatores de Transcrição/genética
18.
Brain Res ; 766(1-2): 276-80, 1997 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-9359616

RESUMO

Concentrations of the neuroactive steroid 3alpha,5alpha-tetrahydroprogesterone (TH PROG or allopregnanolone) and its precursors progesterone (PROG) and 5alpha-dihydroprogesterone (DH PROG) have been measured in mouse brain throughout the oestrous cycle. Plasma PROG concentrations were also measured for comparison. At each stage, circadian fluctuations were found in the concentrations of brain PROG and its metabolites. Such fluctuations were greater than those attributable to any particular stage of the oestrous cycle. Over the entire cycle, a significant correlation was found between brain TH PROG (or DH PROG) and PROG concentrations but not between brain TH PROG (or DH PROG) and plasma PROG concentrations. There was also no correlation between endogenous TH PROG (or DH PROG) and activity of the 5alpha-reductase converting 3H-PROG to 3H-DH PROG in whole brain homogenates. Concentrations of another neuroactive steroid, pregnenolone sulphate (PREG S), in the brain during the oestrous cycle were in phase with plasma PROG but not brain PROG concentrations. Our results indicate that circadian and ovarian influences on the concentrations of PROG and its metabolite TH PROG in female whole mouse brain are caused predominantly by changes in the supply of PROG from within the tissue, whatever the contribution of peripheral sources.


Assuntos
Estro/metabolismo , Moduladores GABAérgicos/metabolismo , Pregnanodionas/metabolismo , Pregnanolona/metabolismo , Progesterona/metabolismo , 3-Hidroxiesteroide Desidrogenases/metabolismo , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica) , 5-alfa-Di-Hidroprogesterona , Animais , Encéfalo/enzimologia , Química Encefálica/fisiologia , Ritmo Circadiano/fisiologia , Feminino , Camundongos
19.
Health Psychol ; 15(1): 56-60, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8788541

RESUMO

The effects of alcohol intoxication on mediators of condom use were examined in a laboratory-based experiment. Twenty men were randomly assigned to either an alcohol or a nonalcohol beverage administration condition. Participants in the experimental condition drank vodka and tonic to achieve a blood alcohol level of 0.08%, whereas controls drank tonic only. All participants then completed a battery of measures related to condom and AIDS-related knowledge, motivation to use condoms, and behavioral self-efficacy regarding condom use. Findings from this exploratory study, which should be considered preliminary because of the small sample size, indicated that participants who received alcohol tended to report more negative attitudes toward condoms and lower self-efficacy to initiate condom use than controls. AIDS knowledge, appraisal of social norms regarding condom use, and perceived risk of infection were unaffected by alcohol consumption.


Assuntos
Intoxicação Alcoólica/psicologia , Preservativos , Infecções por HIV/prevenção & controle , Assunção de Riscos , Comportamento Sexual , Adulto , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Motivação
20.
Health Psychol ; 17(6): 559-68, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9848807

RESUMO

Self-efficacy theory has had considerable influence in studies of health-related behaviors, including the prevention of sexual transmission of HIV. However, imprecise operationalization of self-efficacy theory in HIV prevention research is common and has important implications for the prediction of risk-reducing behavior from self-efficacy beliefs. In many instances, constructs other than self-efficacy have been assessed. In this article, the operationalization and measurement of self-efficacy in the context of HIV-risk-reduction research are reviewed and challenges inherent to such efforts are identified. Recommendations for enhancing the prediction of risk-reducing behavior from self-efficacy beliefs are also provided.


Assuntos
Atitude Frente a Saúde , Infecções por HIV/psicologia , Assunção de Riscos , Autoeficácia , Infecções por HIV/transmissão , Humanos , Valor Preditivo dos Testes , Psicometria , Comportamento Sexual
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