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1.
Can Fam Physician ; 67(2): 114-120, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33608364

RESUMEN

OBJECTIVE: To determine whether changes to the appearance of an emergency department (ED) waiting room influenced the number of patients who left without being seen (LWBS). DESIGN: Retrospective analysis using National Ambulatory Care Reporting System data collected at the time of patient registration. SETTING: The ED of Belleville General Hospital, a mid-sized secondary care community hospital in Ontario with a catchment population of 125 000. PARTICIPANTS: All unscheduled patients registering at the hospital to be seen in the ED from July 1 to December 31, 2016 (control period), and from July 1 to December 31, 2017 (study period). MAIN OUTCOME MEASURES: The volume of patients registering by Canadian Triage and Acuity Scale (CTAS) level to be seen in the ED during the study period compared with the volume of patients registering during the control period, and the number of LWBS during the 2 time periods. RESULTS: The average number of patients registered per month was significantly greater in the study period than in the control period (t 10 = -5.53, P < .01). A total increase of 1881 registrations was recorded in the study period, or 10.47% (increase per month ranged from 9.59% to 11.66%). The proportion of patients with less acute triage scores decreased in the study period; however, the differences in CTAS levels between the 2 years was not statistically significant (χ 2 = 1.05, P = .90). The number of LWBS according to CTAS level was lower in all categories in the study period, including those in the less acute levels, decreasing from 60 in CTAS 5 in 2016 to 45 in 2017, and 585 in CTAS 4 in 2016 to 330 in 2017. Overall, the distribution of LWBS by CTAS level was significantly different between the control and study periods (P < .01). CONCLUSION: The number of patients registering is influenced by the apparent high or low occupancy of the waiting area at the time of registration.


Asunto(s)
Servicio de Urgencia en Hospital , Triaje , Humanos , Ontario/epidemiología , Estudios Retrospectivos
2.
Can Fam Physician ; 67(2): e61-e67, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33608373

RESUMEN

OBJECTIVE: To determine the effect of a physician assistant (PA) working in a secondary care hospital emergency department (ED) on the overall performance of the ED. DESIGN: A retrospective review of ED data from April 1, 2017, to September 30, 2017. SETTING: Belleville General Hospital, a secondary care hospital, ED in Ontario. PARTICIPANTS: A physician assistant, 13 emergency physicians, and 7 family physicians. MAIN OUTCOME MEASURES: Overall ED performance was evaluated using metrics from the Ontario Ministry of Health and Long-Term Care: rate of patients who left without being seen, provider initial assessment time at the 90th percentile, and the average provider initial assessment time for all patients over a 6-month period. RESULTS: In the PA group, there was a lower average daily left without being seen rate (3.4% vs 5.2%; P < .001), a lower provider initial assessment time at the 90th percentile (3.9 hours vs 4.5 hours; P < .001), a lower average provider initial assessment time (114.83 minutes vs 139.46 minutes; P < .001), and a lower average length of stay (313.85 minutes vs 348.91 minutes; P < .001). CONCLUSION: This study suggests that a PA has a statistically significant positive effect on the overall performance of an ED. Future studies should examine the effect of a PA on quality of care and hospital funding.


Asunto(s)
Benchmarking , Asistentes Médicos , Estudios de Cohortes , Servicio de Urgencia en Hospital , Humanos , Tiempo de Internación , Ontario , Estudios Retrospectivos
3.
JMIR Res Protoc ; 10(2): e22902, 2021 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-33538703

RESUMEN

BACKGROUND: Urinary incontinence (UI) and lower urinary tract symptoms (LUTS) are commonly experienced by adult patients in hospitals (inpatients). Although peak bodies recommend that health services have systems for optimal UI and LUTS care, they are often not delivered. For example, results from the 2017 Australian National Stroke Audit Acute Services indicated that of the one-third of acute stroke inpatients with UI, only 18% received a management plan. In the 2018 Australian National Stroke Audit Rehabilitation Services, half of the 41% of patients with UI received a management plan. There is little reporting of effective inpatient interventions to systematically deliver optimal UI/LUTS care. OBJECTIVE: This study aims to determine whether our UI/LUTS practice-change package is feasible and effective for delivering optimal UI/LUTS care in an inpatient setting. The package includes our intervention that has been synthesized from the best-available evidence on UI/LUTS care and a theoretically informed implementation strategy targeting identified barriers and enablers. The package is targeted at clinicians working in the participating wards. METHODS: This is a pragmatic, real-world, before- and after-implementation study conducted at 12 hospitals (15 wards: 7/15, 47% metropolitan, 8/15, 53% regional) in Australia. Data will be collected at 3 time points: before implementation (T0), immediately after the 6-month implementation period (T1), and again after a 6-month maintenance period (T2). We will undertake medical record audits to determine any change in the proportion of inpatients receiving optimal UI/LUTS care, including assessment, diagnosis, and management plans. Potential economic implications (cost and consequences) for hospitals implementing our intervention will be determined. RESULTS: This study was approved by the Hunter New England Human Research Ethics Committee (HNEHREC Reference No. 18/10/17/4.02). Preimplementation data collection (T0) was completed in March 2020. As of November 2020, 87% (13/15) wards have completed implementation and are undertaking postimplementation data collection (T1). CONCLUSIONS: Our practice-change package is designed to reduce the current inpatient UI/LUTS evidence-based practice gap, such as those identified through national stroke audits. This study has been designed to provide clinicians, managers, and policy makers with the evidence needed to assess the potential benefit of further wide-scale implementation of our practice-change package. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/22902.

4.
Science ; 200(4340): 451-3, 1978 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-417398

RESUMEN

Ejaculations decreased and mount latencies increased when intact males were paired regularly over a 3.5-year period (3180 tests) with ovariectomized females made constantly receptive by daily injections of estradiol. The deterioration in potency was abruptly and completely reversed by substituting a group of new but similarly treated females for the original ones.


Asunto(s)
Macaca mulatta/fisiología , Macaca/fisiología , Conducta Sexual Animal/fisiología , Animales , Eyaculación , Femenino , Haplorrinos , Masculino , Apareamiento , Periodicidad , Estaciones del Año , Testosterona/sangre , Factores de Tiempo
5.
Science ; 186(4170): 1217-9, 1974 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-4432068

RESUMEN

Vaginal samples (682) were collected by a tampon method from 50 healthy young women. Samples were analyzed by gas chromatography. The volatile aliphatic acids increased during the late follicular phase of the menstrual cycle and declined progressively during the luteal phase. Women on oral contraceptives had lower amounts of volatile acids and did not show any rhythmic changes in acid content during the menstrual cycle. These same substances possess sex-attractant properties in other primate species.


Asunto(s)
Líquidos Corporales/análisis , Ácidos Grasos Volátiles/análisis , Vagina , Acetatos/análisis , Animales , Líquidos Corporales/efectos de los fármacos , Cromatografía de Gases , Anticonceptivos Orales/farmacología , Femenino , Humanos , Macaca , Menstruación , Factores de Tiempo
6.
Science ; 172(3986): 964-6, 1971 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-4995585

RESUMEN

Fractionation of vaginal secretions from rhesus monkeys by partitioning and chromatographic procedures, combined with behavioral studies, demonstrates that short-chain aliphatic acids are responsible for stimulating the sexual behavior of males. Injection of estradiol into ovariectomized females increases the concentration of volatile acids in secretions which will then sexually stimulate these male primates.


Asunto(s)
Feromonas/aislamiento & purificación , Conducta Sexual Animal , Vagina/metabolismo , Animales , Castración , Cromatografía de Gases , Estradiol/farmacología , Femenino , Haplorrinos , Masculino , Odorantes , Olfato
7.
Can J Occup Ther ; 76(2): 81-9, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19456086

RESUMEN

BACKGROUND: Consumer feedback about experiences with the health system is integral to service planning and is consistent with growing interest in patient-centred care. PURPOSE: To explore the experiences of community-dwelling stroke survivors at one, three and five years using a community-based, cross-sectional study. METHODS: The quantitative study was comprised of 90 participants post-stroke (3 cohorts, each including 30 participants). Qualitative interviews were undertaken with 12 participants (4 participants from each cohort). This paper presents findings from the qualitative component of the project. FINDINGS: The majority of participants in each cohort were independent and a high proportion required community services. Qualitative data identified varied experiences with the health system, including knowledge about stroke, communication with the health system, and influences on transition home. IMPLICATIONS: The results presented identify the need for ongoing health professional education to enhance stroke service delivery. There is a particular need to address stroke risk-factor modification and to ensure close collaboration with patients and other health professionals with regard to rehabilitation processes. Results identify experiences with health systems up to five years post-stroke. Occupational therapy can play an essential role in post-stroke education and in rehabilitation focused on adjustment to stroke.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Programas Nacionales de Salud/organización & administración , Satisfacción del Paciente , Accidente Cerebrovascular/terapia , Adulto , Anciano , Anciano de 80 o más Años , Australia , Estudios de Cohortes , Comunicación , Estudios Transversales , Humanos , Persona de Mediana Edad , Investigación Cualitativa , Características de la Residencia , Estudios Retrospectivos , Factores de Tiempo
8.
Beilstein J Nanotechnol ; 9: 490-498, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29515961

RESUMEN

An important issue in the emerging field of multifrequency atomic force microscopy (MF-AFM) is the accurate and fast demodulation of the cantilever-tip deflection signal. As this signal consists of multiple frequency components and noise processes, a lock-in amplifier is typically employed for its narrowband response. However, this demodulator suffers inherent bandwidth limitations as high-frequency mixing products must be filtered out and several must be operated in parallel. Many MF-AFM methods require amplitude and phase demodulation at multiple frequencies of interest, enabling both z-axis feedback and phase contrast imaging to be achieved. This article proposes a model-based multifrequency Lyapunov filter implemented on a field-programmable gate array (FPGA) for high-speed MF-AFM demodulation. System descriptions and simulations are verified by experimental results demonstrating high tracking bandwidths, strong off-mode rejection and minor sensitivity to cross-coupling effects. Additionally, a five-frequency system operating at 3.5 MHz is implemented for higher harmonic amplitude and phase imaging up to 1 MHz.

9.
Beilstein J Nanotechnol ; 8: 1407-1426, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28900596

RESUMEN

In this review paper, traditional and novel demodulation methods applicable to amplitude-modulation atomic force microscopy are implemented on a widely used digital processing system. As a crucial bandwidth-limiting component in the z-axis feedback loop of an atomic force microscope, the purpose of the demodulator is to obtain estimates of amplitude and phase of the cantilever deflection signal in the presence of sensor noise or additional distinct frequency components. Specifically for modern multifrequency techniques, where higher harmonic and/or higher eigenmode contributions are present in the oscillation signal, the fidelity of the estimates obtained from some demodulation techniques is not guaranteed. To enable a rigorous comparison, the performance metrics tracking bandwidth, implementation complexity and sensitivity to other frequency components are experimentally evaluated for each method. Finally, the significance of an adequate demodulator bandwidth is highlighted during high-speed tapping-mode atomic force microscopy experiments in constant-height mode.

10.
Neurosci Biobehav Rev ; 16(4): 569-83, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1480352

RESUMEN

We review evidence that schedule-controlled intracranial self-stimulation (ICSS) has properties in common with conventional reinforcements, such as food and water, but unlike the latter, animals will respond for ICSS for long periods of time at a near-constant rate. Schedule-controlled ICSS has proven to be more sensitive to drug-induced changes than has ICSS on a continuous reinforcement schedule, and it permits a more fine-grained analysis of the pattern of responding that results in the reinforcement. Evidence is accumulating that the schedule of ICSS itself leads to neurochemical changes in areas of the brain, such as the nucleus accumbens, in which reward processes occur. Results obtained from schedule-controlled ICSS would complement those obtained by drug self-administration studies which generally use intermittent reinforcement. A systematic examination of ICSS schedules at different brain sites would greatly facilitate our interpretation of drug effects and this would have utility for behavioral pharmacology.


Asunto(s)
Conducta Animal/efectos de los fármacos , Autoestimulación/fisiología , Animales , Humanos , Esquema de Refuerzo
11.
Endocrinology ; 118(5): 1935-44, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3698902

RESUMEN

To identify the metabolites of estradiol (E2) and testosterone (T) in nuclei obtained from the female primate brain and, hence, to investigate the mechanism of their actions on behavior, 9 ovariectomized adult rhesus monkeys were studied. Two of these females were injected with 5.5 mCi [3H]T, and 30 min later, samples of 14 brain areas, pituitary gland, and peripheral tissues were removed and homogenized. Purified cell nuclei and a crude cytosol fraction were prepared, extracted with ether, and fractionated by HPLC to identify steroid metabolites. In nuclei from the hypothalamus, preoptic area, and amygdala, [3H]E2 formed locally was the major form of radioactivity. In nuclei from the clitoris, [3H]dihydrotestosterone was the major form of radioactivity, and in nuclei in all other brain samples and in the pituitary gland and uterus, [3H]T predominated. Two females (controls) were pretreated for 5 days with oil sc, injected with 1 mCi [3H]E2, and killed 60 min later. In these females, elevated nuclear concentrations of [3H]E2 were found in the hypothalamus, preoptic area, amygdala, pituitary gland, and uterus. Similar results were obtained in 2 females that were pretreated for 5 days with 2 mg/day dihydrotestosterone propionate, sc, and then injected with 1 mCi [3H]E2. In 3 females that were pretreated for 5 days with 2 mg/day T propionate, sc, and then injected with 1 mCi [3H]E2, levels of [3H]E2 were reduced by 100% (P less than 0.01) in nuclei from preoptic area and amygdala compared with control values and by 78% (P less than 0.05) in nuclei from the hypothalamus. There were no comparable reductions in steroid levels in cerebral cortex, pituitary gland, or uterus. This is the first direct evidence in the brain of a female primate that the actions of T and E2 involve the same receptor systems.


Asunto(s)
Encéfalo/metabolismo , Núcleo Celular/metabolismo , Estradiol/metabolismo , Testosterona/metabolismo , Amígdala del Cerebelo/metabolismo , Androstenodiona/metabolismo , Animales , Encéfalo/efectos de los fármacos , Dihidrotestosterona/metabolismo , Dihidrotestosterona/farmacología , Estradiol/farmacología , Femenino , Hipotálamo/metabolismo , Macaca mulatta , Ovariectomía , Hipófisis/metabolismo , Área Preóptica/metabolismo , Distribución Tisular , Útero/metabolismo
12.
Endocrinology ; 124(3): 1319-26, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2917514

RESUMEN

Testosterone is secreted by the fetal testis during gestation, and this is thought to influence certain aspects of the brain's subsequent development. To study this action at the neuronal level, nine macaque fetuses were injected with 250 microCi [3H]testosterone via the umbilical vein at about 120 days gestation. After 60 min, samples of brain and peripheral tissue were studied by autoradiography or HPLC. Purified nuclear pellets were prepared, and radioactivity in ether extracts was fractionated by HPLC and identified by coelution with internal standard steroids. Concentrations of radioactivity were significantly higher (P less than 0.05) in the hypothalamus-preoptic area than in amygdala, hippocampus, midbrain, and cerebral and cerebellar cortexes, and most of the radioactivity (75%) in the hypothalamus-preoptic area coeluted with 17 beta-estradiol. Radioactivity coeluting with 17 beta-estradiol was also detected in nuclear fractions from amygdala (44%). In contrast, 80% of the radioactivity extracted from pituitary gland nuclei coeluted with testosterone. Most of the neurons labeled in autoradiograms were located in the hypothalamus and preoptic area, fewer were found in the amygdala, and labeling in the frontal or motor cortex did not exceed chance levels. Results suggested that aromatization and, consequently, estrogen receptors play a role in the effects of testosterone on the hypothalamus and amygdala of the primate fetus at this stage of development.


Asunto(s)
Encéfalo/embriología , Hipófisis/embriología , Testosterona/metabolismo , Amígdala del Cerebelo/metabolismo , Animales , Autorradiografía , Encéfalo/metabolismo , Núcleo Celular/metabolismo , Cromatografía , Estradiol/metabolismo , Edad Gestacional , Hipotálamo/metabolismo , Macaca fascicularis , Macaca mulatta , Neuronas/metabolismo , Hipófisis/metabolismo , Área Preóptica/metabolismo , Testosterona/sangre , Distribución Tisular , Tritio
13.
J Clin Endocrinol Metab ; 71(4): 868-74, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2401716

RESUMEN

To examine the possible sites of action of the synthetic estrogen diethylstilbestrol (DES) in the developing primate, [3H]DES (250 mu Ci, iv, or 500 mu Ci, sc) was administered directly into two rhesus and nine cynomolgus macaque fetuses at about 122 days gestation (range, 121-124 days). The location of cells accumulating radioactivity 60 min later was examined by autoradiography in two males and two females. In females, labeled neurons were observed in the hypothalamus, preoptic area, and amygdala, but not in the cerebral cortex. In one male a similar pattern of uptake was observed, but percentages of labeled neurons were lower, and in the other male very little labeling was observed in any region. The chemical identity of the radioactivity in cell nuclei was determined by high performance liquid chromatography in three males and four females. Concentrations of radioactivity in nuclear pellets were highest in the hypothalamus and lowest in the cerebral cortex. This regional variation was highly significant (P less than 0.001), but there was no significant difference between nuclear concentrations of radioactivity in males and females. In supernatant fractions, concentrations of radioactivity showed no significant variation between brain regions and after 60 min, 52-67% of the extracted radioactivity was no longer in the form of [3H]DES. Nuclear levels of radioactivity in pituitary glands and genital tracts of both male and female fetuses were 2-5 times higher than those in hypothalamus. The results demonstrated a direct interaction between DES and cell nuclei from specific regions of the brain, pituitary gland, and genital tract at this stage of gestation in a primate.


Asunto(s)
Encéfalo/metabolismo , Dietilestilbestrol/metabolismo , Feto/metabolismo , Genitales Femeninos/metabolismo , Genitales Masculinos/metabolismo , Hipófisis/metabolismo , Animales , Autorradiografía , Núcleo Celular/metabolismo , Cromatografía Líquida de Alta Presión , Dietilestilbestrol/sangre , Femenino , Sangre Fetal/análisis , Macaca fascicularis , Macaca mulatta , Masculino , Neuronas/metabolismo
14.
Am J Psychiatry ; 140(7): 883-6, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6859305

RESUMEN

An analysis by the cosinor method of over 50,000 rapes in 16 different locations in the United States revealed statistically significant annual rhythms in 14 locations, with maxima in the summer. Changes in numbers of rapes and assaults showed similar seasonal patterns, suggesting that rape comprised a subcategory of aggressive behavior. In contrast, there was a virtual absence of seasonal changes in numbers of murders. A close relation emerged between assaults and rapes, on the one hand, and temperature, on the other, in different geographical locations. The authors hypothesize that human violence, just like aggression in nonhuman primates, is influenced by exteroceptive environmental factors.


Asunto(s)
Violación , Estaciones del Año , Violencia , Femenino , Homicidio , Humanos , Masculino , Temperatura , Estados Unidos
15.
Am J Psychiatry ; 143(5): 637-40, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-3963253

RESUMEN

Over 27,000 reports about women abused by their live-in male partners were provided by 23 shelter organizations in five locations in the United States. Cosinor analyses revealed statistically significant annual rhythms in the frequencies of abuse, with maxima in the summer. The rhythms were closely related to annual changes in ambient temperature in these locations, and the time of the maxima was similar to those previously reported for assaults and rapes. The findings support the hypothesis that violence by men toward women increases in summer independently of any major seasonal changes in the opportunity for contact between perpetrator and victim.


Asunto(s)
Agresión/psicología , Periodicidad , Femenino , Humanos , Masculino , Violación , Estaciones del Año , Factores Sexuales , Temperatura , Estados Unidos , Violencia
16.
J Comp Neurol ; 206(3): 273-7, 1982 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-7085933

RESUMEN

Autoradiography was used to localize target cells for 3H-testosterone or its labeled metabolites in the brain of the rhesus monkey. Two castrated males were injected intravenously with 3H-testosterone (2 mCi/monkey) and were killed 1 hour later. In both animals, neurons that concentrated radioactivity in their nuclei were located in a well-circumscribed system that included the bed nucleus (n.) of the stria terminalis, medial preoptic n., suprachiasmatic preoptic n., anterior hypothalamic area, ventromedial hypothalamic n., cortical, medial, and basal accessory amygdaloid n., mesencephalic reticular n., and periaqueductal gray matter. In contrast to reports in some nonprimate mammalian species, little or no cellular labeling was observed in the lateral septum, arcuate n.-median eminence, motor nuclei of cranial nerves, or spinal cord.


Asunto(s)
Encéfalo/metabolismo , Testosterona/metabolismo , Amígdala del Cerebelo/metabolismo , Animales , Autorradiografía , Mapeo Encefálico , Castración , Hipotálamo/metabolismo , Macaca mulatta , Masculino , Mesencéfalo/metabolismo , Área Preóptica/metabolismo
17.
J Comp Neurol ; 193(3): 789-804, 1980 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-7440791

RESUMEN

Estrogens participate in the regulation of gonadotropin secretion and in the control of sexual and aggressive behavior. To elucidate the neuroanatomical substrate for these actions in the female cat, the topographical distribution of estrogen-concentrating cells in the brain was studied by autoradiography. One hour after the intravenous injection of 1 mCi (3 microgram) of 3H-estradiol in three adult ovariectomized cats, radioactivity was concentrated in the nuclei of neurons in several brain areas. Within the telencephalon, high concentrations of moderately to heavily labeled cells were found in the lateral and posterior septal nuclei (n.), bed n. of the stria terminalis (medial division), medial and central amygdaloid n., and amygdalo-hippocampal area. There were also many less strongly labeled cells in the ventral dentate gyrus. Within the diencephalon, many heavily labeled cells were distributed in the medial and periventricular preoptic n., anterior hypothalamic area, and infundibular, ventromedial, and periventricular hypothalamic n. In the brain stem, some labeled cells were located throughout the periaqueductal gray, and in the laminar spinal trigeminal n., n. of the solitary tract, n. incertus, marginal n. of the superior cerebellar peduncle, rostral linear n., and interfascicular n. Although minor differences were noted, the topographical distribution of estradiol-concentrating cells in the female cat brain agreed closely with that reported in other vertebrate species.


Asunto(s)
Encéfalo/metabolismo , Estradiol/metabolismo , Receptores de Estrógenos/metabolismo , Animales , Autorradiografía , Mapeo Encefálico , Gatos , Ventrículos Cerebrales/metabolismo , Diencéfalo/metabolismo , Femenino , Mesencéfalo/metabolismo , Telencéfalo/metabolismo
18.
J Comp Neurol ; 235(3): 336-42, 1985 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-3998214

RESUMEN

The location of neurons that concentrate progestin in the brains of female cynomolgus monkeys was mapped by autoradiography using the specific synthetic progestin receptor ligand 3H-ORG 2058. Three females were ovariectomized and treated with estrogen (20 micrograms estradiol benzoate daily for 7 days), and one of them was also pretreated with progesterone. Each received an i.v. injection of 1 mCi 3H-ORG 2058 and was killed 1 hour later. Thaw-mount autoradiograms revealed intense accumulation of radioactivity in the nuclei of many neurons in the mediobasal hypothalamus, particularly in the ventromedial nucleus (n.), arcuate n., and premammillary n. Neuronal labeling was also observed frequently in the medial preoptic n., and occasionally in the anterior hypothalamic area, paraventricular n., and organum vasculosum of the lamina terminalis. In the pituitary gland, about 5% of cells in the pars distalis were intensely labeled. In the female pretreated with progesterone, however, labeling was almost completely blocked. Analysis of samples by high-performance liquid chromatography demonstrated that the radioactivity extracted from brain and pituitary gland cell nuclei was almost entirely unmetabolized 3H-ORG 2058. The nuclear concentration of progestin was much greater in the pituitary gland than in the brain, and was greater in the hypothalamus than in any other brain area. These results revealed well-localized groups of progestin-concentrating neurons in the primate brain which presumably mediate the effects of progesterone on both gonadotropin secretion and female sexual behavior.


Asunto(s)
Encéfalo/metabolismo , Pregnenodionas/metabolismo , Animales , Autorradiografía , Química Encefálica , Cromatografía Líquida de Alta Presión , Femenino , Galago , Cobayas , Hipotálamo/metabolismo , Macaca fascicularis , Macaca mulatta , Hipófisis/metabolismo , Pregnenodionas/análisis , Ratas
19.
J Comp Neurol ; 408(2): 220-36, 1999 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-10333272

RESUMEN

Bilateral lesions of the central tegmental field (CTF) in male rats virtually eliminate mating behavior. This study examined if mating-induced Fos expression (a measure of neuronal activation) and androgen receptors (AR) are colocalized in brain and spinal cord neurons which project to the CTF. Animals received unilateral injections of the retrograde tracer Fluorogold (FG) in the lateral part of the CTF (CTFl), and 10 days later were killed after ejaculating with females. Brains and spinal cords were examined for FG transport, AR-immunoreactivity (AR-ir), and Fos-immunoreactivity (Fos-ir). AR-ir and Fos-ir were visualized with fluorescence microscopy using cyanine-conjugated and fluorescein-conjugated secondary antibodies. The CTFl received projections from AR-containing neurons in forebrain structures (bed nucleus of stria terminalis, medial preoptic area, lateral and ventromedial hypothalamus), in the central amygdala and various mid- and hindbrain structures (dorsolateral tegmentum, superior and inferior colliculi, pedunculopontine nucleus), and in the lumbosacral spinal cord (lamina X). Some of the AR-containing neurons in bed nucleus of stria terminalis and in the dorsal part of the medial preoptic area with projections to the CTFl were activated by mating. Most AR-containing neurons in spinal lamina X with projections to the CTFl were also activated by mating. Information from spinal cord and pontine nuclei and from outputs descending from the forebrain may be relayed in the CTFl. Thus, as part of a network of hormone-sensitive neurons linking brain and spinal cord mechanisms for mating, the CTFl could participate in the integration of visceral and somatic information relevant for sexual behavior.


Asunto(s)
Encéfalo/fisiología , Eyaculación/fisiología , Neuronas/fisiología , Proteínas Proto-Oncogénicas c-fos/genética , Ratas Long-Evans/fisiología , Receptores Androgénicos/metabolismo , Conducta Sexual Animal/fisiología , Médula Espinal/fisiología , Estilbamidinas , Animales , Transporte Axonal , Encéfalo/citología , Colorantes Fluorescentes , Regulación de la Expresión Génica , Genes fos , Masculino , Neuronas/citología , Especificidad de Órganos , Proteínas Proto-Oncogénicas c-fos/análisis , Ratas , Ratas Long-Evans/anatomía & histología , Receptores Androgénicos/análisis , Médula Espinal/citología , Tegmento Mesencefálico/fisiología
20.
Neuropharmacology ; 25(2): 125-31, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3703168

RESUMEN

The acute effects of nicotine (0.03-1.0 mg/kg) were studied in a locomotor activity procedure and in a series of intracranial self-stimulation (ICSS) paradigms. Nicotine produced a dose-dependent decrease in locomotor activity. When animals were trained to lever-press for intracranial self-stimulation on a continuous reinforcement schedule (CRF), the drug was ineffective except at the 1.0 mg/kg dose, which produced a moderate decrease in the rate of responding. However, when animals were tested in a fixed-ratio:15 (FR:15) paradigm, nicotine produced a steep, biphasic dose-response curve. At the 0.1 mg/kg dose, the response rates were increased to approx. 60% above baseline, while at the 1.0 mg/kg dose, response rates were decreased to approx. 90% below baseline values. The effects of nicotine were also studied in an auto-titration procedure which measured the rewarding value of the stimulus. There was a decrease in performance at larger doses similar to that observed in the continuous reinforcement procedure, but there were no significant changes in the threshold for reinforcement. Nicotine did not produce any change in the detection threshold for stimulation of the brain. In acute studies, therefore, nicotine produced both stimulation and disruption of behavior, effects that were brought to light by the fixed-ratio schedule of reinforcement, and this may relate to the rewarding effects of nicotine.


Asunto(s)
Condicionamiento Operante/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Nicotina/farmacología , Animales , Masculino , Ratas , Esquema de Refuerzo , Autoestimulación
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