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1.
Am J Physiol Endocrinol Metab ; 295(5): E1167-71, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18812459

RESUMO

The neurohypophysial hormone oxytocin (OT), synthesized in magnocellular paraventricular (PVN) and supraoptic (SON) nuclei, is well known for its effects in lactation. Our previous studies showed that central OT receptor (OTR) binding is increased during gestation and that blockade of central OTRs, specifically during mid-late gestation, causes a delay in OT release during suckling and reduces weight gain in pups, suggesting decreased milk delivery. In the present study, we tested whether central OTR blockade during late gestation disrupts the gestation-related plasticity in intrinsic membrane properties. Whole cell current-clamp recordings were performed in OT neurons from pregnant rats (19-22 days in gestation) that were infused with an OTR antagonist (OTA) or artificial cerebrospinal fluid (aCSF) and from virgin rats infused with aCSF into the third ventricle via an osmotic minipump beginning on days 12-14 of gestation. The amplitudes of both Ca(2+)-dependent afterhyperpolarizations (AHPs), an apamin-sensitive medium AHP (mAHP) and an apamin-insensitive slow AHP (sAHP), were significantly increased during late gestation in control pregnant animals. However, the amplitude of the sAHP from pregnant rats treated with the OTA was significantly smaller than that of pregnant control rats and similar to that of virgins. These results indicate that the diminished efficiency in lactation due to OTR blockade may be partly a result of an altered sAHP that would shape OT bursting. These findings suggest that central actions of OT during late gestation are necessary for programming the plasticity of at least some of the intrinsic membrane properties in OT neurons during lactation.


Assuntos
Hipotálamo Anterior/fisiologia , Neurônios/fisiologia , Receptores de Ocitocina/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Apamina/farmacologia , Eletrofisiologia , Feminino , Idade Gestacional , Hipotálamo Anterior/citologia , Hipotálamo Anterior/efeitos dos fármacos , Lactação/fisiologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Ornipressina/análogos & derivados , Ornipressina/farmacologia , Ocitocina/antagonistas & inibidores , Ocitocina/farmacologia , Ocitocina/fisiologia , Gravidez , Ratos , Receptores de Ocitocina/antagonistas & inibidores , Vasopressinas/fisiologia
2.
Exp Neurol ; 196(2): 210-23, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16157332

RESUMO

The central and systemic release of oxytocin (OT) has been well documented during parturition and lactation. In preparation for the demands of these events, the magnocellular hypothalamic neurons of the central OT system undergo a variety of biochemical, molecular, electrophysiological, and anatomical adaptations during gestation. However, the mechanisms responsible for these changes have not been well established. A number of neurochemical mediators have been implicated in contributing to the plasticity in the OT magnocellular system during gestation, including ovarian hormones, as well as central neurotransmitters, such as glutamate, gamma-amino butyric acid (GABA), and central neurosteroids, e.g., allopregnanolone. In addition, several lines of evidence suggest that central OT release and subsequent OT receptor stimulation may contribute to adaptations of the OT system during gestation, and may be necessary for its subsequent functioning during lactation. Here, we review evidence for involvement of the neurochemical systems implicated in contributing to adaptations that occur in the OT system during the course of gestation.


Assuntos
Hipotálamo Anterior/citologia , Plasticidade Neuronal , Neurônios/metabolismo , Neurotransmissores/metabolismo , Ocitocina/metabolismo , Gravidez/fisiologia , Animais , Feminino , Lactação/fisiologia , Receptores de Ocitocina/fisiologia , Fatores de Tempo
3.
J Neuroendocrinol ; 15(8): 743-8, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12834434

RESUMO

There is evidence that the central oxytocin system is activated and undergoes reorganization before parturition. The present study was designed to determine the effects of central oxytocin receptor blockade during late gestation on parturition, pup growth, and oxytocin release during suckling. Female Sprague-Dawley rats were implanted on gestation day 12-14 with Alzet osmotic minipumps containing an oxytocin receptor antagonist (d(CH2)5, Tyr(Me)(2), Orn(8)-vasotocin; OT-X) or artificial cerebrospinal fluid (VEH), which was infused into the third cerebral ventricle. Pumps were removed within 24 h of parturition. Daily maternal body weight and food intake were monitored during gestation and lactation. The length of gestation, duration of parturition, pup number, litter weight and interbirth interval were recorded. Subsequently, pup number and litter weights were recorded daily until lactation day 10 or 11, when maternal and pup behaviour, and plasma oxytocin concentration before and during suckling were measured. Central oxytocin blockade had no effect on the timing of parturition, maternal behaviour, litter size, still births, or litter weights at birth. However, beginning on day 3 of lactation, average weights of litters of OT-X females were significantly lower than litters of VEH-treated females. Furthermore, while basal plasma oxytocin concentrations, oxytocin increases in response to suckling and dam/pup interactions did not differ between groups, a significant delay in suckling-induced systemic oxytocin release was observed in OT-X females. Finally, OT-X dams weighed less than VEH dams during the postpartum observation period, although food intakes were similar. These data suggest that central actions of oxytocin during late gestation are necessary for the normal timing of systemic release of oxytocin during suckling, normal pup weight gain, and maintenance of maternal body weight.


Assuntos
Comportamento Materno/efeitos dos fármacos , Ocitocina/análogos & derivados , Ocitocina/metabolismo , Receptores de Ocitocina/antagonistas & inibidores , Receptores de Ocitocina/fisiologia , Animais , Animais Lactentes , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Idade Gestacional , Lactação , Ocitocina/farmacologia , Parto/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
4.
J Exp Biol ; 206(Pt 10): 1697-706, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12682101

RESUMO

To better understand the full extent of the odorant detection capabilities of fish, we investigated the olfactory sensitivity of zebrafish to a monoamine and several polyamines using electrophysiological and activity-dependent labeling techniques. Electro-olfactogram (EOG) recording methods established the relative stimulatory effectiveness of these odorants as: spermine >> spermidine approximately agmatine > glutamine > putrescine >or= cadaverine >or= histamine > artificial freshwater. The detection threshold for the potent polyamines was approximately 1 micromol l(-1). Cross-adaptation experiments suggested that multiple receptors are involved in polyamine detection. Three observations indicated that polyamine signaling may involve a transduction cascade distinct from those used by either amino acids or bile salts. Like bile salts and the adenylate cyclase activator forskolin, but unlike amino acid odorants, polyamines failed to stimulate activity-dependent labeling of olfactory sensory neurons with the cation channel permeant probe agmatine, suggesting a signaling pathway different from that used by amino acid stimuli. Also supporting distinct amino acid and polyamine signaling pathways is the finding that altering phospholipase C activity with the inhibitor U-73122 significantly reduced amino acid-evoked responses, but had little effect on polyamine- (or bile salt-) evoked responses. Altering cyclic nucleotide-mediated signaling by adenylate cyclase activation with forskolin, which significantly reduced responses to bile salts, failed to attenuate polyamine responses, suggesting that polyamines and bile salts do not share a common transduction cascade. Collectively, these findings suggest that polyamines are a new class of olfactory stimuli transduced by a receptor-mediated, second messenger signaling pathway that is distinct from those used by amino acids or bile salts.


Assuntos
Poliaminas Biogênicas/análise , Odorantes/análise , Olfato/fisiologia , Peixe-Zebra/fisiologia , Adaptação Fisiológica , Animais , Poliaminas Biogênicas/farmacologia , Colforsina/farmacologia , Eletrofisiologia , Feminino , Masculino , Neurônios Receptores Olfatórios/efeitos dos fármacos , Neurônios Receptores Olfatórios/fisiologia , Sistemas do Segundo Mensageiro , Transdução de Sinais , Olfato/efeitos dos fármacos
5.
Biol Psychiatry ; 50(12): 965-77, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11750893

RESUMO

BACKGROUND: Limited studies of hypothalamic-pituitary-adrenal axis regulation in posttraumatic stress disorder have been performed in premenopausal women. We therefore undertook a study of hypothalamic-pituitary-adrenal axis regulation in this population. METHODS: Outpatient posttraumatic stress disorder subjects were compared with healthy, age- and weight-matched nontraumatized subjects. Subjects were free from psychotropic medications, alcohol and other illicit substances for at least 4 weeks before study. Menstrual cycle phase was determined by monitoring the LH surge and plasma progesterone levels. Corticotropin releasing factor and adrenocorticotropin stimulation tests, as well as 24-hour urinary-free cortisol measurements were performed. RESULTS: Corticotropin releasing factor test: Baseline adrenocorticotropic hormone and cortisol levels did not differ between the 12 PTSD and 11 comparison subjects, but the posttraumatic stress disorder group had greater adrenocorticotropic hormone and cortisol responses to corticotropin releasing factor, as well as a later cortisol peak. Adrenocorticotropic hormone test: Baseline cortisol levels did not differ between the 10 posttraumatic stress disorder subjects and seven controls, but the posttraumatic stress disorder group showed greater cortisol responses to adrenocorticotropic hormone. Peak cortisol responses to corticotropin releasing factor and adrenocorticotropic hormone were correlated with each other and with 24-hour urinary-free cortisol excretion. CONCLUSIONS: Pituitary and adrenal hyperreactivity to exogenous corticotropin releasing factor and adrenocorticotropic hormone is demonstrated in premenopausal women with chronic posttraumatic stress disorder. Cortisol hyperreactivity thus may play a role in the pathophysiology of posttraumatic stress disorder in women.


Assuntos
Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Pré-Menopausa , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Hormônio Adrenocorticotrópico , Adulto , Estudos de Casos e Controles , Doença Crônica , Hormônio Liberador da Corticotropina , Feminino , Humanos , Hidrocortisona/sangue , Hidrocortisona/urina , Ciclo Menstrual , Testes de Função Adreno-Hipofisária , Transtornos de Estresse Pós-Traumáticos/etiologia , Transtornos de Estresse Pós-Traumáticos/metabolismo , Regulação para Cima
6.
Am J Primatol ; 55(2): 101-15, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11668528

RESUMO

Behavioral patterns were quantified in seven heterosexual lesser bushbaby (Galago moholi) pairs during the estrous cycle to determine the relative significance of behavioral and nonbehavioral components of female sexuality in mate attraction. Increases in the occurrence of several male behaviors indicating female attractiveness were initiated during vaginal swelling when the female was sexually nonreceptive. Female behavioral estrus, as indicated by intromission, was confined to a portion of vaginal opening coinciding with proestrous and vaginal estrous smears. Female attractiveness was maintained for much of the period of vaginal opening, whereas female receptivity ended a day or two earlier than attractiveness. Female receptive and proceptive behaviors were not well defined or extensive, and few female behaviors exhibited significant changes during the cycle. Scent-marking behaviors, such as urine washes, and male grooms, were generally elevated outside the behavioral estrous period. In G. moholi, male sexual arousal appears to be elicited primarily by female attractiveness, while behavioral components of female sexuality appear to be less important in influencing mate attraction.


Assuntos
Estro , Galago/psicologia , Comportamento Sexual , Animais , Animais de Zoológico , Feminino , Galago/fisiologia , Masculino , Atrativos Sexuais
7.
J Nerv Ment Dis ; 189(8): 532-40, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11531205

RESUMO

Gender-specific rates of violence exposure and violence perpetration among psychiatrically ill adolescents has received little scientific attention. We examined 130 adolescent inpatients and found no difference between male and female subjects with respect to self-reported violence potential or actual violence perpetration. Female inpatients, however, were significantly more often victims of sexual assault, and male inpatients were significantly more often victims of physical assault. For male inpatients, a history of violence perpetration in one area was closely linked with a history of violence victimization in the same area. Alternatively, patterns of victimization and perpetration among female inpatients were less predictable and had crossover to victimization and perpetration experiences in other areas. Correlational analyses revealed that violence risk was associated with a broad range of internalizing and externalizing psychopathology. Significant associations with hopelessness, suicidality, and childhood trauma differentiated the violence risk of male and female inpatients. We propose a hypothesis for understanding these differences and conclude that although psychiatrically ill adolescent male and female patients may commonly fall victim to differing forms of violence, both genders are at equal risk for actual violence perpetration.


Assuntos
Hospitalização , Transtornos Mentais/diagnóstico , Violência/estatística & dados numéricos , Adolescente , Fatores Etários , Criança , Maus-Tratos Infantis/psicologia , Maus-Tratos Infantis/estatística & dados numéricos , Abuso Sexual na Infância/estatística & dados numéricos , Feminino , Humanos , Masculino , Transtornos Mentais/psicologia , Inventário de Personalidade/estatística & dados numéricos , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Psicologia do Adolescente , Psicometria , Reprodutibilidade dos Testes , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/psicologia , Inquéritos e Questionários , Violência/psicologia
8.
Compr Psychiatry ; 42(4): 283-90, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11458302

RESUMO

To examine psychological and behavioral correlates of community violence exposure in psychiatrically hospitalized adolescents, 89 inpatients were administered a battery of psychometrically well-established self-report instruments. Violence exposure was assessed using the Child's Exposure to Violence Checklist (CEVC). Half of the patients reported exposure to multiple incidents violence in their community (52%) and home (53%). Sixty-one percent were victims of physical assault, and 39% were victims of sexual assault. Patients who had witnessed community violence reported significantly more post-traumatic stress disorder (PTSD) symptoms, drug use, and violence potential than patients without a history of witnessing community violence. Patients exposed to community violence were also more likely to be the victim of childhood maltreatment, as well as a perpetrator of violence. In conclusion, traumatization via exposure to community violence may serve as one important determinant in the development of mixed internalizing and externalizing psychopathology in adolescent inpatients, thus necessitating accurate assessment and treatment planning.


Assuntos
Transtornos Mentais/reabilitação , Características de Residência , Violência/psicologia , Adolescente , Agressão/psicologia , Alcoolismo/diagnóstico , Criança , Transtornos Disruptivos, de Controle do Impulso e da Conduta/diagnóstico , Feminino , Hospitalização , Humanos , Masculino , Transtornos Mentais/etiologia , Transtornos de Estresse Pós-Traumáticos/psicologia
9.
J Am Acad Child Adolesc Psychiatry ; 39(9): 1104-11, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10986806

RESUMO

OBJECTIVE: To identify clinical and functional correlates of posttraumatic stress disorder (PTSD) in trauma-exposed urban adolescent girls. METHOD: Ninety female adolescents aged 12 to 21 years (mean 17.3 years) who presented for routine medical care at an adolescent primary care clinic were assessed with self-report questionnaires and interviews for trauma exposure, posttraumatic stress symptoms, other psychopathology, and psychosocial, family, and school function. RESULTS: Ninety-two percent (n = 83) endorsed at least one trauma. Witnessing community violence (85.6%) and hearing about a homicide (67.8%) were the most common traumatic events endorsed. Twelve (14.4%) and 10 (11.6%) traumatized girls met DSM-IV symptom criteria for full and partial PTSD, respectively. Compared with traumatized girls without PTSD, girls with PTSD were significantly more depressed, used more cigarettes and marijuana, and were more likely to have failed a school grade, been suspended from school, or been arrested. CONCLUSIONS: Urban adolescent girls are exposed to multiple types of trauma. Whereas most develop at least one posttraumatic stress symptom, girls who meet full symptom criteria for PTSD show evidence of other psychopathology, increased cigarette and marijuana use, and poorer school performance. Further research is needed to identify and treat inner-city girls with PTSD.


Assuntos
Negro ou Afro-Americano/psicologia , Atenção Primária à Saúde/estatística & dados numéricos , Transtornos do Comportamento Social/psicologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , População Urbana/estatística & dados numéricos , Violência/psicologia , Adolescente , Comportamento do Adolescente/etnologia , Comportamento do Adolescente/psicologia , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Criança , Connecticut/epidemiologia , Feminino , Humanos , Áreas de Pobreza , Prevalência , Escalas de Graduação Psiquiátrica , Transtornos do Comportamento Social/etnologia , Transtornos de Estresse Pós-Traumáticos/etnologia , Violência/estatística & dados numéricos
10.
J Nerv Ment Dis ; 188(6): 349-56, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10890343

RESUMO

This study examined gender differences in the associations between posttraumatic stress symptoms and problematic substance use in psychiatrically hospitalized adolescents. Ninety-five adolescent inpatients (38 boys, 57 girls) were systematically evaluated with a battery of psychometrically well-established self-report measures to assess trauma exposure, posttraumatic stress symptoms, problematic alcohol and drug use, and internalizing and externalizing psychopathology. Twenty-three percent (N = 22) of patients met DSM-IV-based symptom criteria for PTSD, and 37% (N = 35) and 34% (N = 32) of patients endorsed problematic levels of drug and alcohol use, respectively. Posttraumatic stress symptoms were significantly associated with problematic drug and alcohol use in girls but not in boys. There were no significant gender differences in posttraumatic stress symptoms and/or problematic substance use, to account for the gender differences in the association between PTSD and substance use. Our findings suggest that the link between substance abuse and PTSD may be especially salient for female adolescents.


Assuntos
Hospitalização , Transtornos Mentais/diagnóstico , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Adolescente , Comorbidade , Diagnóstico Duplo (Psiquiatria) , Feminino , Humanos , Masculino , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Inventário de Personalidade/estatística & dados numéricos , Fatores Sexuais , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
11.
Am J Physiol Renal Physiol ; 278(4): F576-84, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10751218

RESUMO

Herein we demonstrate that replicative cellular senescence in vitro results in sharply reduced inositol 1,4,5-trisphosphate (IP(3)) receptor levels, reduced mitogen-evoked IP(3) formation and Ca(2+) release, and Ca(2+) store depletion. Human diploid fibroblasts (HDFs) underwent either 30 mean population doublings [mean population doublings (MPDs) thymidine labeling index (TI) >92% ("young") or between 53 and 58 MPDs (TI < 28%; "senescent")]. We found that the cytosolic Ca(2+) release triggered by either ionomycin or by several IP(3)-generating mitogens, namely bradykinin, thrombin, platelet-derived growth factor (PDGF), and epidermal growth factor (EGF), was attenuated markedly in senescent HDFs. Notably, the triggered cytosolic Ca(2+) transients were of a smaller magnitude in senescent HDFs. However, the response latency seen with both PDGF and EGF was greater for senescent cells. Finally, a smaller proportion of senescent HDFs showed oscillations. In parallel, IP(3) formation in response to bradykinin or EGF was also attenuated in senescent HDFs. Furthermore, senescent HDFs displayed a sharply diminished Ca(2+) release response to intracellularly applied IP(3). Finally, to compare IP(3) receptor protein levels directly in young and senescent HDFs, their microsomal membranes were probed in Western blots with a highly specific anti-IP(3) receptor antiserum, Ab(40). A approximately 260-kDa band corresponding to the IP(3) receptor protein was noted; its intensity was reduced by approximately 50% in senescent cells. Thus, we suggest that reduced IP(3) receptor expression, lowered IP(3) formation, and Ca(2+) release, as well as Ca(2+) store depletion, all contribute to the deficient Ca(2+) signaling seen in HDFs undergoing replicative senescence.


Assuntos
Canais de Cálcio/metabolismo , Fibroblastos/fisiologia , Inositol 1,4,5-Trifosfato/biossíntese , Receptores Citoplasmáticos e Nucleares/metabolismo , Bradicinina/farmacologia , Cálcio/metabolismo , Células Cultivadas , Senescência Celular/fisiologia , Criança , Citosol/metabolismo , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Substâncias de Crescimento/farmacologia , Humanos , Inositol 1,4,5-Trifosfato/farmacologia , Receptores de Inositol 1,4,5-Trifosfato , Mitógenos/farmacologia , Trombina/farmacologia
12.
Biol Psychiatry ; 47(2): 137-43, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10664830

RESUMO

BACKGROUND: The demands of the Wisconsin Card Sorting Test (WCST) change with experience. This report contains two studies designed to examine N-methyl-D-aspartate (NMDA) receptor contributions to the executive components of WCST performance. These aspects of WCST performance figure more prominently in the initial completion of this task than in subsequent task repetitions in healthy populations. METHODS: In the first study, healthy subjects (n = 15) completed the WCST on two occasions separated by 1 week. In the second study, healthy subjects (n = 22) completed two test days spaced by approximately 1 week, during which, they completed the WCST and other assessments after administration of the NMDA antagonist ketamine (intravenous bolus 0.26 mg/kg followed by infusion of 0.65 mg/kg/hour) or matched placebo. RESULTS: In the first study, subjects reduced the number of total and perseverative errors with a single repetition of the WCST. In the second study, ketamine significantly increased the number of total errors and the number and percent of perseverative errors on the first, but not the second test day. Similarly, it reduced the number of category criteria met on the first, but not second test day. Ketamine also increased distractibility, impaired recall, produced psychosis, altered perception, and had effects resembling the negative symptoms of schizophrenia. However, only WCST performance showed order dependency. CONCLUSIONS: This order dependency further implicates NMDA receptors in executive cognitive functions associated with the frontal cortex.


Assuntos
Anestésicos Dissociativos/efeitos adversos , Transtornos Cognitivos/induzido quimicamente , Ketamina/efeitos adversos , Aprendizagem/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Adulto , Nível de Alerta/efeitos dos fármacos , Transtornos Cognitivos/diagnóstico , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Desempenho Psicomotor/efeitos dos fármacos
13.
J Neurophysiol ; 82(6): 3160-7, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10601449

RESUMO

Although it is generally assumed that fish are capable of discriminating amino acid odorants on the basis of differences in side-chain structure, less is known about their ability to discriminate amino acids with modifications to alpha-carboxyl and alpha-amino groups. In this study, the ability of the zebrafish olfactory system to detect and presumably discriminate analogues of the basic amino acid Arg was assessed, by using cross-adaptation and activity-dependent labeling techniques. Electrophysiological recordings established that esterification (L-arginine methyl ester; AME) or deletion (agmatine or amino-4-guanidobutane; AGB) of the alpha-carboxyl group yielded odorants more potent than Arg, whereas deletion of the alpha-amino group (L-argininic acid; AA) yielded a less potent analogue. In cross-adaptation experiments, no test-competitor odorant combination yielded complete cross-adaptation, suggesting the detection of these Arg analogues by multiple odorant receptors (ORs) with partially nonoverlapping specificities. Activity-dependent immunocytochemical labeling of olfactory receptor neurons supported this conclusion. AGB, an ion-channel-permeant probe (and odorant), labeled 4.9 +/- 0.4% (n = 24) of sensory epithelium, whereas the addition of Arg, 1-ethylguanidine sulfate, L-alpha-amino-beta-guanidinopropionate, or AME to AGB resulted in a significant elevation of labeling (8-14%). This study provides evidence that the olfactory system has the potential to discriminate among amino acid odorants with modified alpha-carboxyl and alpha-amino groups.


Assuntos
Arginina/análogos & derivados , Arginina/farmacologia , Discriminação Psicológica/fisiologia , Neurônios Receptores Olfatórios/fisiologia , Olfato/fisiologia , Adaptação Fisiológica/fisiologia , Animais , Eletrofisiologia , Feminino , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Masculino , Odorantes , Relação Estrutura-Atividade , Peixe-Zebra
14.
Compr Psychiatry ; 40(6): 422-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10579373

RESUMO

The study objective was to examine correlates of suicide risk in psychiatrically hospitalized adolescents with a reported history of childhood abuse. Predictors of suicide risk were examined in 74 subjects who reported a history of childhood abuse and 53 depressed subjects who did not report a history of childhood abuse. Subjects completed a battery of psychometrically well-established self-report instruments to assess childhood abuse, suicide risk, and internalizing and externalizing psychopathology. Correlational analyses showed that higher levels of depression, self-criticism, and hopelessness were significantly associated with suicide risk in both study groups and violence was significantly associated with suicide risk in the childhood abuse group. For the childhood abuse group, multiple regression analyses with seven predictor variables accounted for 54% of the variance in suicide risk; depression and alcohol problems made significant independent contributions, while violence and self-criticism were independent predictors at the trend level. For the depressed/nonabused group, multiple regression analyses with the seven predictor variables accounted for 60% of the variance in suicide risk; depression, hopelessness, and self-criticism were independent predictors. Our findings suggest that both internalizing (i.e., depression or self-criticism) and externalizing (i.e., violence or alcohol) factors predict suicide risk in adolescent inpatients who report childhood abuse. This profile appears different from the more internalizing pattern (i.e., depression, self-criticism, and hopelessness) observed for the depressed adolescent inpatients who reported no history of childhood abuse.


Assuntos
Maus-Tratos Infantis/psicologia , Transtorno Depressivo/psicologia , Transtorno Depressivo/reabilitação , Suicídio/psicologia , Adolescente , Criança , Estudos Transversais , Transtorno Depressivo/diagnóstico , Feminino , Hospitalização , Hospitais Psiquiátricos , Humanos , Comportamento Impulsivo/diagnóstico , Comportamento Impulsivo/psicologia , Masculino , Valor Preditivo dos Testes , Testes Psicológicos , Fatores de Risco , Autoimagem , Índice de Gravidade de Doença , Inquéritos e Questionários , Violência/psicologia
15.
Compr Psychiatry ; 40(5): 347-52, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10509616

RESUMO

Seventy-one consecutive psychiatrically hospitalized adolescents (34 males and 37 females) were systematically asked about their experiences of sexual abuse, physical abuse, and witnessing home violence using a reliable 46-item self-report measure of maltreatment, the Traumatic Events Questionnaire-Adolescent Version (TEQ-A). Subjects' responses were compared with a "best-estimate" source consisting of data from child protective service and police reports, medical records, and clinician interviews. Rates of agreement varied from 88% (kappa value [kappa] = .75) for sexual abuse, to 83% (kappa = .65) for physical abuse, to 75% (kappa = .49) for witnessing home violence. Disclosures of maltreatment were not significantly influenced by the gender, age, educational level, or ethnicity of the adolescent. Disclosures were highest for sexual abuse (86%) and lowest for witnessing home violence (68%). The results show that psychiatrically hospitalized adolescents' self-reports of maltreatment experiences generally concur very well with best-estimate sources.


Assuntos
Abuso Sexual na Infância/estatística & dados numéricos , Maus-Tratos Infantis/estatística & dados numéricos , Violência Doméstica/estatística & dados numéricos , Admissão do Paciente/estatística & dados numéricos , Revelação da Verdade , Adolescente , Maus-Tratos Infantis/diagnóstico , Maus-Tratos Infantis/psicologia , Abuso Sexual na Infância/diagnóstico , Abuso Sexual na Infância/psicologia , Coleta de Dados/estatística & dados numéricos , Violência Doméstica/psicologia , Feminino , Humanos , Masculino , Inventário de Personalidade/estatística & dados numéricos , Psicometria , Reprodutibilidade dos Testes
16.
J Cell Biochem ; 74(3): 357-71, 1999 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10412038

RESUMO

Cells of the bone marrow stroma can reversibly convert among different phenotypes. Based on this and on evidence for a reciprocal relationship between osteoblastogenesis and adipogenesis, we have isolated several murine bone marrow-derived clonal cell lines with phenotypic characteristics of osteoblasts or adipocytes, or both. Consistent with a state of plasticity, cell lines with a mixed phenotype synthesized osteoblast markers like type I collagen, alkaline phosphatase, osteocalcin, as well as the adipocyte marker lipoprotein lipase, under basal conditions. In the presence of ascorbic acid and beta-glycerophosphate-agents that promote osteoblast differentiation-they formed a mineralized matrix. In the presence of isobutylmethylxanthine, hydrocortisone, and indomethacin-agents that promote adipocyte differentiation-they accumulated fat droplets, but failed to express adipsin and aP2, markers of terminally differentiated adipocytes. Furthermore, they were converted back to matrix mineralizing cells when the adipogenic stimuli were replaced with the osteoblastogenic ones. A prototypic cell line with mixed phenotype (UAMS-33) expressed Osf2/Cbfa1-a transcription factor required for osteoblast differentiation, but not PPARgamma2-a transcription factor required for terminal adipocyte differentiation. Stable transfection with a PPARgamma2 expression construct and activation with the thiazolidinedione BRL49653 stimulated aP2 and adipsin synthesis and fat accumulation, and simultaneously suppressed Osf2/Cbfa1, alpha1(I) procollagen, and osteocalcin synthesis. Moreover, it rendered the cells incapable of forming a mineralized matrix. These results strongly suggest that PPARgamma2 negatively regulates stromal cell plasticity by suppressing Osf2/Cbfa1 and osteoblast-like biosynthetic activity, while promoting terminal differentiation to adipocytes.


Assuntos
Proteínas de Neoplasias , Osteoblastos/metabolismo , Receptores Citoplasmáticos e Nucleares/fisiologia , Tiazolidinedionas , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Medula Óssea/metabolismo , Diferenciação Celular , Linhagem Celular , Subunidade alfa 1 de Fator de Ligação ao Core , Expressão Gênica , Lipase Lipoproteica/metabolismo , Camundongos , Osteoblastos/efeitos dos fármacos , Fenótipo , Rosiglitazona , Tiazóis/farmacologia , Transfecção
17.
J Am Acad Child Adolesc Psychiatry ; 38(4): 385-92, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10199109

RESUMO

OBJECTIVE: To describe the diagnostic comorbidity and clinical correlates of posttraumatic stress disorder (PTSD) in adolescent psychiatric inpatients. METHOD: Seventy-four adolescent inpatients were given a structured diagnostic interview, the revised version of the Diagnostic Interview for Children and Adolescents, and a battery of standard self-report measures to assess general trauma exposure, posttraumatic stress symptoms, suicidal behavior, dissociation, and depression. RESULTS: Ninety-three percent of subjects reported exposure to at least one traumatic event such as being a witness/victim of community violence, witnessing family violence, or being the victim of physical/sexual abuse. Thirty-two percent of subjects met diagnostic criteria for current PTSD, with sexual abuse cited as the most common traumatic stressor in 69% of PTSD cases. Girls were significantly more likely to develop PTSD than boys, although the total number of types of trauma did not differ by gender. Compared with psychiatric controls, male youngsters with PTSD were significantly more likely to have comorbid diagnoses of eating disorders, other anxiety disorders, and somatization disorder. Furthermore, male and female youngsters with PTSD were significantly more likely to have attempted suicide and report greater depressive and dissociative symptoms. CONCLUSION: In clinical populations of hospitalized adolescents exposed to multiple forms of trauma, PTSD is a common, but highly comorbid disorder. Specific multimodal assessments and treatments targeted to both PTSD and its comorbidity profile are warranted.


Assuntos
Transtornos Somatoformes/complicações , Transtornos de Estresse Pós-Traumáticos/complicações , Transtornos de Estresse Pós-Traumáticos/psicologia , Adolescente , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Transtornos Somatoformes/diagnóstico , Transtornos Somatoformes/psicologia , Transtornos de Estresse Pós-Traumáticos/diagnóstico
18.
J Nerv Ment Dis ; 187(1): 32-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9952251

RESUMO

The aim of this study was to assess relative risk of histories of different types of abuse (sexual, physical, and emotional) and neglect (physical and emotional) for suicidal behavior (attempts, ideation, and self-mutilation) in psychiatrically hospitalized adolescents. Seventy-one adolescent inpatients (34 boys, 37 girls) completed self-report measures of abuse and neglect, current suicidal ideation, and lifetime suicide and self-mutilation attempts. The prevalence of sexual and physical abuse was 37.5% and 43.7%, respectively, with 31.3% and 61% of youngsters reporting emotional and physical neglect. Fifty-one percent of youngsters had made suicide attempts, and 39% had self-mutilated. Suicide attempters were significantly more likely to be female, Latino, to report sexual, physical, and emotional abuse, and to endorse emotional neglect. In multivariate analyses, female gender, sexual abuse, and emotional neglect remained significant predictors of self-mutilation and suicidal ideation. Female gender and sexual abuse remained significant predictors of suicide attempts. These findings suggest that emotional neglect is an important and deleterious component of maltreatment experiences and may be a more powerful predictor of suicidal behavior in hospitalized adolescents than physical abuse, emotional abuse, and physical neglect.


Assuntos
Maus-Tratos Infantis/estatística & dados numéricos , Hospitalização , Transtornos Mentais/epidemiologia , Suicídio/psicologia , Suicídio/estatística & dados numéricos , Adolescente , Fatores Etários , Idade de Início , Criança , Comorbidade , Feminino , Humanos , Masculino , Transtornos Mentais/psicologia , Análise Multivariada , Prevalência , Psicologia do Adolescente , Fatores de Risco , Automutilação/epidemiologia , Fatores Sexuais , Tentativa de Suicídio/psicologia , Tentativa de Suicídio/estatística & dados numéricos
19.
J Trauma Stress ; 12(4): 641-54, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10646182

RESUMO

This study assesses the consistency of adolescents' reports of sexual and physical abuse via two self-report questionnaires with different measurement approaches and examines demographic and psychopathological characteristics that influence abuse reporting. Seventy adolescent inpatients completed the Childhood Trauma Questionnaire (CTQ) (Likert-type items are summed to form dimensional scales, and cutoff scores determine abuse status), the Traumatic Events Questionnaire--Adolescents (multiple-choice items determine abuse status) and measures of depression, suicidal ideation, and dissociative symptoms. Consistent reports of physical and sexual abuse were given by 86% and 71% of youngsters, respectively. Discrepant reporters of sexual abuse were significantly more likely to be male, whereas consistent reporters were significantly more depressed and suicidal and reported higher levels of sexual abuse and emotional and physical neglect. Adolescents, for the most part, were consistent in their responses about sexual and physical abuse on both a Likert scale and a direct-answer-format questionnaire. The CTQ had a lower threshold for detection of sexual abuse, particularly for boys.


Assuntos
Abuso Sexual na Infância/diagnóstico , Abuso Sexual na Infância/estatística & dados numéricos , Transtornos de Estresse Pós-Traumáticos/reabilitação , Inquéritos e Questionários , Adolescente , Criança , Abuso Sexual na Infância/psicologia , Transtornos Dissociativos/diagnóstico , Feminino , Hospitalização , Humanos , Entrevista Psicológica , Masculino , Programas de Rastreamento , Prevalência , Testes Psicológicos , Transtornos de Estresse Pós-Traumáticos/etiologia
20.
Stem Cells ; 16(4): 261-70, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9708448

RESUMO

In long-term bone marrow cultures we studied the effect of the addition of the myelotoxic agents methotrexate (MTX) and ceftazidime (CEF) on the kinetics of cytokine production in the supernatant (SN) and on mRNA expression in the adherent stromal layer. In response to a medium change, a prompt and significant increase in colony-stimulating activity (CSA) and interleukin 6 (IL-6) concentrations in the SN occurred, peaking 12 h later. Two macrophage colony-stimulating factors (M-CSF) mRNA of 23 kb and 4 kb were identified. In response to the medium change, the 4.0-kb transcript increased significantly six h later. The 2.3-kb transcript expression was stronger than the 4-kb mRNA but did not cycle with medium change. At medium change, IL-6 mRNA was only minimally expressed; then a prompt increase occurred, which peaked six h later. The addition of 500 mg/ml (=915 microM) CEF to the culture caused a dose-dependent suppression of CSA and IL-6 supernatant concentrations and IL-6 and M-CSF mRNA expression. By contrast, 1 microM MTX had minimal effect on cytokine concentrations in the SN following medium change. mRNA expression was, however, suppressed. These results provide insights into the possible mechanisms whereby cytokines lead to increased myeloid cell proliferation following medium change. We also demonstrate that two myelotoxic agents have different effects on cytokine production. This information could be of value in developing rational approaches to the therapeutic use of cytokines in drug-induced neutropenia.


Assuntos
Células da Medula Óssea/efeitos dos fármacos , Ceftazidima/farmacologia , Inibidores do Crescimento/farmacologia , Interleucina-6/biossíntese , Fator Estimulador de Colônias de Macrófagos/biossíntese , Metotrexato/farmacologia , Animais , Células da Medula Óssea/metabolismo , Técnicas de Cultura de Células , Feminino , Expressão Gênica , Interleucina-6/genética , Fator Estimulador de Colônias de Macrófagos/genética , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro , Fatores de Tempo
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