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3.
Orbit ; 33(3): 226-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24660981

RESUMO

BACKGROUND: Orbital sub-periosteal haematoma (OSH) is usually caused by orbital trauma. We present a case of spontaneous OSH and review the literature on this condition. METHODS: We present a case of sub-periosteal haematoma secondary to migraine and vigorous emesis. DISCUSSION: OSH is very rare; this case highlights the clinical features of the condition and that rapid spontaneous resolution can occur. We review the literature on emesis- or valsava-induced OSH and discuss possible mechanisms for its formation in conjunction with migraine.


Assuntos
Hematoma/etiologia , Doenças Orbitárias/etiologia , Vômito/complicações , Feminino , Humanos , Adulto Jovem
4.
Ann R Coll Surg Engl ; 95(8): 586-90, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24165342

RESUMO

INTRODUCTION: We report the outcomes of a long-term surveillance programme for individuals with a family history of colorectal cancer. METHODS: The details of patients undergoing a colonoscopy having been referred on the basis of family history of colorectal cancer were entered prospectively into a database. Further colonoscopy was arranged on the basis of the findings. The outcomes assessed included incidence of cancer and adenoma identification at initial and subsequent colonoscopy. RESULTS: The records of 2,293 patients (917 men; median patient age: 51 years) were entered over 22 years, giving data on 3,982 colonoscopies. Eight adverse events (0.2%) were recorded. Twenty-seven cancers were found at first colonoscopy and thirteen developed during the follow-up period. There were significantly more cancers identified in those with more than one first-degree relative with cancer than in other groups (p=0.01). The number of adenomas identified at subsequent surveillance colonoscopies remained constant with between 9.3% and 12.0% of patients having adenomas that were removed. Two-thirds (68%) of patients with cancer and three-quarters (77%) with adenomas fell outside the British Society of Gastroenterology (BSG) 2006 guidelines. CONCLUSIONS: Repeated colonoscopy continues to yield significant pathology including new cancers. These continue to occur despite removal of adenomas at prior colonoscopies. The majority of patients with cancers and adenomas fell outside the BSG 2006 guidelines; more would have fallen outside the 2010 guidelines.


Assuntos
Adenoma/diagnóstico , Colonoscopia/estatística & dados numéricos , Neoplasias Colorretais/diagnóstico , Adenoma/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colonoscopia/efeitos adversos , Neoplasias Colorretais/genética , Detecção Precoce de Câncer , Saúde da Família , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Linhagem , Retratamento/estatística & dados numéricos , Adulto Jovem
6.
Consult Pharm ; 24(6): 439-46, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19555154

RESUMO

OBJECTIVE: To examine racial differences in medication use by older long-stay Veterans Affairs Nursing Home Care Unit (NHCU) patients. DESIGN: Longitudinal study. SETTINGS: 133 Veterans Affairs NHCUs. PARTICIPANTS: Three thousand four hundred eighty veterans 65 years of age or older admitted between January 1, 2004, and June 30, 2005, for 90 days or more. MAIN OUTCOMES MEASURES: Prevalence of those taking nine or more medications (i.e., polypharmacy) and medications from specific therapeutic medication classes. Racial differences were determined using 0.05 level chi-squared tests. RESULTS: The sample consisted of 14.3% who were black. Blacks compared with whites (all comparisons P < 0.05 except where noted) were younger (13.6% vs. 17.4%, older than 85 years of age), had less depression (22.24 vs. 29.79%), less allergies (9.82% vs. 20.36%), and a similar rate of moderate-to severe pain (22.65% vs. 24.05; P = 0.49). The percent of polypharmacy was similar by race (blacks 74.35% vs. whites 71.18%; P = 0.62), as was the prevalence of medication class use with the exceptions that blacks were less likely than whites to take central nervous system (CNS) medications (75.75% vs. 80.14%; P = 0.02) and antihistamines (13.03% vs. 16.8%; P = 0.04). Specifically, blacks were less likely than whites to receive a selective serotonin-reuptake inhibitor (SSRI) antidepressant (20.84% vs. 27.17%; P < 0.01) or a second-generation antihistamine (3.41% vs. 6.51%; P < 0.01), but more likely than whites to receive opioids (14.63% vs. 11.27%; P = 0.03). CONCLUSION: There appears to be racial differences in the overall use of antihistamines and CNS medications and some of their subclasses.


Assuntos
Casas de Saúde/organização & administração , Preparações Farmacêuticas/administração & dosagem , Polimedicação , Idoso , Idoso de 80 Anos ou mais , População Negra/estatística & dados numéricos , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Estudos Longitudinais , Masculino , Estados Unidos , United States Department of Veterans Affairs , Veteranos/estatística & dados numéricos , População Branca/estatística & dados numéricos
8.
J Am Geriatr Soc ; 57(2): 335-40, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19170784

RESUMO

OBJECTIVES: To establish consensus oral dosing guidelines for primarily renally cleared medications prescribed for older adults. DESIGN: Literature search followed by a two-round modified Delphi survey. SETTING: A nationally representative survey of experts in geriatric clinical pharmacy. PARTICIPANTS: Eleven geriatric clinical pharmacists. MEASUREMENTS: After a comprehensive literature search and review by an investigative group of six physicians (2 general internal medicine, 2 nephrology, 2 geriatrics), 43 dosing recommendations for 30 medications at various levels of renal function were created. The expert panel rated its agreement with each of these 43 dosing recommendations using a 5-point Likert scale (1=strongly disagree to 5=strongly agree). Recommendation-specific means and 95% confidence intervals were estimated. Consensus was defined as a lower 95% confidence limit of greater than 4.0 for the recommendation-specific mean score. RESULTS: The response rate was 81.8% (9/11) for the first round. All respondents who completed the first round also completed the second round. The expert panel reached consensus on 26 recommendations involving 18 (60%) medications. For 10 medications (chlorpropamide, colchicine, cotrimoxazole, glyburide, meperidine, nitrofurantoin, probenecid, propoxyphene, spironolactone, and triamterene), the consensus recommendation was not to use the medication in older adults below a specified level of renal function (e.g., creatinine clearance <30 mL/min). For the remaining eight medications (acyclovir, amantadine, ciprofloxacin, gabapentin, memantine, ranitidine, rimantadine, and valacyclovir), specific recommendations for dose reduction or interval extension were made. CONCLUSION: An expert panel of geriatric clinical pharmacists was able to reach consensus agreement on a number of oral medications that are primarily renally cleared.


Assuntos
Idoso/fisiologia , Rim/fisiologia , Preparações Farmacêuticas/administração & dosagem , Administração Oral , Idoso de 80 Anos ou mais , Técnica Delphi , Humanos
9.
Eur Radiol ; 18(11): 2691-700, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18491104

RESUMO

The aims of this study were to detect morphological changes in neuroanatomical components in adult survivors of acute lymphoblastic leukemia (ALL). Voxel-based morphometry (VBM) can be used to detect subtle structural changes in brain morphology and via analysis of fractional anisotropy (FA), diffusion-tensor imaging (DTI) can non-invasively probe white matter (WM) integrity. We used VBM and DTI to examine 20 long-term survivors of ALL and 21 healthy matched controls. Ten ALL survivors received chemotherapy and irradiation; ten survivors received chemotherapy alone during childhood. Imaging was performed on a 3.0-T MRI. For VBM, group comparisons of segmented T1-weighted grey matter (GM) and WM images from controls and ALL survivors were performed separately for patients who received chemotherapy alone and who received chemotherapy and irradiation. For DTI, FA in WM was compared for the same groups. Survivors of childhood ALL who underwent cranial irradiation during childhood had smaller WM volumes and reduced GM concentration within the caudate nucleus and thalamus. The FA in WM was reduced in adult survivors of ALL but the effect was more severe after combined treatment with irradiation and chemotherapy. Our results indicate that DTI and VBM can reveal persistent long-term WM and caudate changes in children after ALL treatment, even without T2 changes in conventional imaging.


Assuntos
Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Leucemia/diagnóstico , Adolescente , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Sobreviventes , Adulto Jovem
10.
Psychiatr Serv ; 59(5): 483-5, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18451002

RESUMO

The Department of Veterans Affairs (VA) provides an ideal opportunity to conduct mental health services research among vulnerable populations, given its extensive data sources, disproportionate number of vulnerable patients (older, often with comorbidities), and quality improvement mission. Although VA facilities are often affiliated with universities, successful VA-academic research partnerships are sometimes elusive. The Continuous Improvement for Veterans in Care: Mood Disorders (CIVIC-MD) study was a partnership with a VA facility that had not been engaged in mood disorders research. This column describes how the partnership formed, key elements of its success, and challenges and opportunities to inform future research partnerships.


Assuntos
Centros Médicos Acadêmicos , Comportamento Cooperativo , Relações Interprofissionais , Serviços de Saúde Mental/normas , Transtornos do Humor , Qualidade da Assistência à Saúde , United States Department of Veterans Affairs , Veteranos/psicologia , Veteranos/estatística & dados numéricos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/epidemiologia , Transtornos do Humor/psicologia , Transtornos do Humor/terapia , Estados Unidos/epidemiologia
11.
Aliment Pharmacol Ther ; 24(4): 585-91, 2006 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-16907891

RESUMO

BACKGROUND: True treatment rates and the impact of comorbidities on treatment rates for hepatitis C virus in the HCV-HIV-coinfected subjects are unknown. AIM: To quantify the rates of treatment prescription and the effect of comorbidities on hepatitis C virus treatment rates in HCV-HIV-coinfected veterans. METHODS: The Veterans Affairs National Patient Care Database was used to identify all hepatitis C virus-infected subjects between 1999 and 2003 using ICD-9 codes. Demographics, comorbidities and pharmacy data were retrieved. We used logistic regression to compare the predictors of hepatitis C virus treatment in hepatitis C virus-monoinfected and HCV-HIV-coinfected subjects. FINDINGS: We identified 120 507 hepatitis C virus-infected subjects, of which 6502 were HIV coinfected. 12% of the hepatitis C virus-monoinfected and 7% of the -coinfected subjects were prescribed hepatitis C virus treatment (P < 0.0001). Those not prescribed treatment were older (48.6 years vs. 47.7 years, P = 0.007) and more likely to be black (52% vs. 32%, P < 0.0001). HIV coinfected was less likely to be prescribed hepatitis C virus treatment (OR 0.74, 95% CI: 0.67-0.82). Among the coinfected subjects, the following were associated with non-treatment (OR, 95% CI): black race (0.45, 0.35-0.57); Hispanic race (0.56, 0.38-0.82); drug use (0.68, 0.53-0.88); anaemia (0.17, 0.11-0.26); bipolar disorder (0.63, 0.40-0.99); major depression (0.72, 0.53-0.99); mild depression (0.47, 0.35-0.62). CONCLUSIONS: A small number of HCV-HIV-coinfected veterans are prescribed treatment for hepatitis C virus. Non-treatment is associated with increasing age, minority race, drug use and psychiatric illness. Further studies are needed to determine the eligibility for treatment and reasons for non-treatment for hepatitis C virus.


Assuntos
Infecções por HIV/complicações , Hepatite C Crônica/terapia , Estudos de Coortes , Atenção à Saúde , Feminino , Hepatite C Crônica/complicações , Humanos , Masculino , Pessoa de Meia-Idade
12.
Neuroscience ; 141(2): 769-779, 2006 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-16753270

RESUMO

Rapid eye movement sleep decreases between 10 and 30 days postnatally in the rat. The pedunculopontine nucleus is known to modulate waking and rapid eye movement sleep, and pedunculopontine nucleus neurons are thought to be hyperpolarized by noradrenergic input from the locus coeruleus. The goal of the study was to investigate the possibility that a change in alpha-2 adrenergic inhibition of pedunculopontine nucleus cells during this period could explain at least part of the developmental decrease in rapid eye movement sleep. We, therefore, recorded intracellularly in 12-21 day rat brainstem slices maintained in oxygenated artificial cerebrospinal fluid. Putative cholinergic vs. non-cholinergic pedunculopontine nucleus neurons were identified using nicotinamide adenine dinucleotide phosphate diaphorase histochemistry and intracellular injection of neurobiotin (Texas Red immunocytochemistry). Pedunculopontine nucleus neurons also were identified by intrinsic membrane properties, type I (low threshold spike), type II (A) and type III (A+low threshold spike), as previously described. Clonidine (20 microM) hyperpolarized most cholinergic and non-cholinergic pedunculopontine nucleus cells. This hyperpolarization decreased significantly in amplitude (mean+/-S.E.) from -6.8+/-1.0 mV at 12-13 days, to -3.0+/-0.7 mV at 20-21 days. However, much of these early effects (12-15 days) were indirect such that direct effects (tested following sodium channel blockade with tetrodotoxin (0.3 microM)) resulted in hyperpolarization averaging -3.4+/-0.5 mV, similar to that evident at 16-21 days. Non-cholinergic cells were less hyperpolarized than cholinergic cells at 12-13 days (-1.6+/-0.3 mV), but equally hyperpolarized at 20-21 days (-3.3+/-1.3 mV). In those cells tested, hyperpolarization was blocked by yohimbine, an alpha-2 adrenergic receptor antagonist (1.5 microM). These results suggest that the alpha-2 adrenergic receptor on cholinergic pedunculopontine nucleus neurons activated by clonidine may play only a modest role, if any, in the developmental decrease in rapid eye movement sleep. Clonidine blocked or reduced the hyperpolarization-activated inward cation conductance, so that its effects on the firing rate of a specific population of pedunculopontine nucleus neurons could be significant. In conclusion, the alpha-2 adrenergic input to pedunculopontine nucleus neurons appears to consistently modulate the firing rate of cholinergic and non-cholinergic pedunculopontine nucleus neurons, with important effects on the regulation of sleep-wake states.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Clonidina/farmacologia , Neurônios/efeitos dos fármacos , Núcleo Tegmental Pedunculopontino/citologia , Acetilcolina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Potenciais de Ação/efeitos da radiação , Antagonistas Adrenérgicos alfa/farmacologia , Análise de Variância , Anestésicos Locais/farmacologia , Animais , Animais Recém-Nascidos , Biotina/análogos & derivados , Biotina/metabolismo , Estimulação Elétrica/métodos , Feminino , Técnicas In Vitro , Masculino , NADP/metabolismo , Neurônios/classificação , Neurônios/fisiologia , Neurônios/efeitos da radiação , Núcleo Tegmental Pedunculopontino/crescimento & desenvolvimento , Gravidez , Pirimidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Tetrodotoxina/farmacologia , Ioimbina/farmacologia
14.
Neurotoxicol Teratol ; 28(2): 210-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16469482

RESUMO

Prenatal exposure to cigarette smoke is known to produce lasting arousal, attentional and cognitive deficits in humans. The pedunculopontine nucleus (PPN), as the cholinergic arm of the reticular activating system (RAS), is known to modulate arousal, waking and rapid eye movement (REM) sleep. REM sleep decreases between 10 and 30 days postnatally in the rat, especially at 12-21 days. Pregnant dams were exposed to 350 ml of cigarette smoke for 15 min, 3 times per day, from day E14 until birth, and the pups allowed to mature. Intracellularly recorded PPN neurons in 12-21 day rat brainstem slices were tested for intrinsic membrane properties, including the hyperpolarization-activated cation current Ih, which is known to drive oscillatory activity. Type II (A-current) PPN cells from 12-16 day old offspring of treated animals had a 1/2max Ih amplitude of (mean +/- SE) 4.1 +/- 0.9 mV, while 17-21 day cells had a higher 1/2max Ih of 9.9 +/- 1.1 mV (p < 0.0001). Cells from 12-16 day old control brainstems had a 1/2max Ih of 1.3 +/- 0.1 mV, which was lower (p < 0.05) than in cells from prenatally treated offspring; while 17-21 day old cells from controls had a 1/2max Ih of 3.3 +/- 0.3 mV, which was also lower (p < 0.01) than in cells from prenatally treated offspring. In addition, changes in resting membrane potential [control -65. +/- 0.9 mV (n=32); exposed -55.0 +/- 1.4 mV (n = 27) (p < 0.0001)], and action potential (AP) threshold [control -56.5 +/- 0.7 mV (n = 32), exposed -47.0 +/- 1.4 mV (n = 27) (p < 0.0001)], suggest that prenatal exposure to cigarette smoke induced marked changes in cells in the cholinergic arm of the RAS, rendering them more excitable. Such data could partially explain the differences seen in individuals whose parents smoked during pregnancy, especially in terms of their hypervigilance and increased propensity for attentional deficits and cognitive/behavioral disorders.


Assuntos
Neurônios/efeitos dos fármacos , Nicotina/farmacologia , Núcleo Tegmental Pedunculopontino , Efeitos Tardios da Exposição Pré-Natal , Fumar , Animais , Animais Recém-Nascidos , Peso Corporal/efeitos dos fármacos , Monóxido de Carbono/sangue , Fármacos Cardiovasculares/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica/métodos , Eletrofisiologia/métodos , Feminino , Viabilidade Fetal/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios/fisiologia , Nicotina/sangue , Núcleo Tegmental Pedunculopontino/efeitos dos fármacos , Núcleo Tegmental Pedunculopontino/crescimento & desenvolvimento , Núcleo Tegmental Pedunculopontino/patologia , Gravidez , Taxa de Gravidez , Pirimidinas/farmacologia , Ratos , Fatores de Tempo
15.
Thalamus Relat Syst ; 3(2): 89-113, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19305519

RESUMO

Thalamic relay neurons have homogeneous, adult-like firing properties and similar morphology by 12 days postnatally (PN 12). Parafascicular (Pf) neurons have a different morphology compared with typical thalamic relay neurons, but the development of their electrophysiological properties is not well studied. Intracellular recordings in PN 12-50 Pf neurons revealed several heterogeneous firing patterns different from those in thalamic relay neurons. Two types of cells were identified: Type I cells displayed a fast afterhyperpolarization (AHP) followed by a large-amplitude, slow AHP; whereas Type II cells had only a fast AHP. These cell types had overlapping membrane properties but differences in excitability. Some properties of Pf neurons were adult-like by PN 12, but, unlike thalamic relay neurons, there were significant maturational changes thereafter, including decreased action potential (AP) duration, increased fast AHP amplitude and increased excitability. Pf neurons did not exhibit rhythmic bursting and generally lacked low-threshold spike (LTS) responses that characterize thalamic relay neurons. Pf neurons exhibited nonlinear I-V relationships, and only a third of the cells expressed the time and voltage-dependent hyperpolarization activated (Ih) current, which declined with age. These results indicate that the morphological differences between Pf neurons and typical thalamic relay neurons are paralleled by electrophysiological differences, and that Pf membrane properties change during postnatal development.

16.
Int J Dent Hyg ; 3(1): 13-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16451372

RESUMO

OBJECTIVES: The purpose of this study was to assess potential risk factors for the development of poor oral hygiene and increased dental caries in individuals with scleroderma. METHODS: Twenty-two subjects with scleroderma participated in this study. All subjects were examined with the Patient Hygiene Performance (PHP) Index, which assesses the extent of plaque and debris over a tooth surface. In addition, oral aperature, xerostomia and dominant upper extremity strength, motion, skin thickness, and dexterity were measured. RESULTS: None of the subjects had good or excellent hygiene. Fifteen subjects had fair oral hygiene and seven subjects had poor oral hygiene as measured by the PHP Index. Significant differences were seen between these two groups for oral aperture, percentage of teeth with caries, skin thickness, dexterity and finger flexion. Dexterity and joint motion correlated significantly with the number of decayed surfaces and number of caries. Oral aperture correlated with the PHP Index and the number of dental caries. CONCLUSIONS: Subjects with poor oral hygiene required more time to complete manual dexterity task and had decreased hand strength and joint motion. Moreover, these same subjects had more contractures, scars, ulcers, and higher skin scores (more disease activity) than subjects in the fair hygiene group. In addition to frequent dental exam and routine cleaning, dental personnel may want to consider exercises to increase oral aperature and investigate toothbrush and dental floss selection used by persons with scleroderma.


Assuntos
Higiene Bucal , Esclerodermia Difusa/complicações , Esclerodermia Limitada/complicações , Cárie Dentária/prevenção & controle , Placa Dentária/terapia , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Boca/anatomia & histologia , Esclerodermia Difusa/fisiopatologia , Esclerodermia Limitada/fisiopatologia , Extremidade Superior/fisiopatologia , Xerostomia/diagnóstico
17.
Neuroimage ; 23(1): 364-9, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15325384

RESUMO

The underlying neurobiology of autism, a severe pervasive developmental disorder, remains unknown. Few neocortical brain MRI abnormalities have been reported. Using rest functional brain imaging, two independent studies have described localized bilateral temporal hypoperfusion in children with primary autism. In order to search for convergent evidence of anatomical abnormalities in autistic children, we performed an anatomical MRI study using optimized whole-brain voxel-based morphometry (VBM). High-resolution 3-D T1-weighted MRI data sets were acquired in 21 children with primary autism (mean age 9.3 +/- 2.2 years) and 12 healthy control children (mean age 10.8 +/- 2.7 years). By comparing autistic children to normal children, we found bilaterally significant decreases of grey matter concentration located in superior temporal sulcus (STS) (P < 0.05 corrected, after small volume correction; SVC). Children with autism were also found to have a decrease of white matter concentration located in the right temporal pole and in cerebellum (P < 0.05, corrected) compared to normal children. These results suggest that autism is associated with bilateral anatomical abnormalities localized in the STS and are remarkably consistent with functional hypoperfusion previously reported in children with autism. The multimodal STS areas are involved in highest level of cortical integration of both sensory and limbic information. Moreover, the STS is now recognized as a key cortical area of the "social brain" and is implicated in social perceptual skills that are characteristically impaired in autism. Therefore, the convergent anatomical and functional temporal abnormalities observed in autism may be important in the understanding of brain behavior relationships in this severe developmental disorder.


Assuntos
Transtorno Autístico/patologia , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Computação Matemática , Lobo Temporal/anormalidades , Adolescente , Atrofia , Transtorno Autístico/diagnóstico , Criança , Dominância Cerebral/fisiologia , Feminino , Humanos , Masculino , Valores de Referência , Percepção Social , Software , Lobo Temporal/patologia
18.
J Neurophysiol ; 91(4): 1470-81, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15010495

RESUMO

The developmental decrease in rapid-eye-movement (REM) sleep in man occurs between birth and after puberty. We hypothesize that if this decrease in REM sleep does not occur, lifelong increases in REM sleep drive may ensue. Such disorders are characterized by hypervigilance and sensory-gating deficits, such as are present in postpubertal onset disorders like schizophrenia, panic attacks (a form of anxiety disorder), and depression. The decrease in REM sleep in the rat occurs between 10 and 30 days of age. We studied changes in size and physiological properties of pedunculopontine nucleus (PPN) cells involved in the control of arousal, i.e., waking and REM sleep. During the largest decrease in REM sleep (12-21 days), cholinergic PPN neurons doubled in cell area, the hypertrophy peaking at 15-16 days, then decreasing in area by 20-21 days. Noncholinergic PPN cells did not change in area during this period. We confirmed the presence of two populations of PPN neurons based on action potential (AP) duration, with the proportion of short-AP-duration cells increasing and long AP duration decreasing between 12 and 21 days. Most cholinergic and noncholinergic cells had short AP durations. Afterhyperpolarization (AHP) duration became segregated into long and short AHP duration after 15 days. Cells with short AP duration also had short AHP duration. The proportion of PPN cells with Ih current increased gradually, peaking at 15 days, then decreased by 21 days. These changes in morphological and physiological properties are discussed in relation to the developmental decrease in REM sleep.


Assuntos
Avidina/análogos & derivados , Neurônios/fisiologia , Tegmento Mesencefálico/citologia , Potenciais de Ação/efeitos dos fármacos , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Avidina/metabolismo , Fármacos Cardiovasculares/farmacologia , Contagem de Células , Tamanho Celular , Feminino , Fluoresceínas/metabolismo , Imuno-Histoquímica/métodos , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , NADP/metabolismo , Neurônios/classificação , Neurônios/efeitos dos fármacos , Gravidez , Pirimidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Bloqueadores dos Canais de Sódio/farmacologia , Tegmento Mesencefálico/embriologia , Tegmento Mesencefálico/crescimento & desenvolvimento , Tetrodotoxina/farmacologia , Xantenos/metabolismo
19.
J Appl Physiol (1985) ; 96(2): 735-46, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14527968

RESUMO

Rapid eye movement (REM) sleep in the human declines from approximately 50% of total sleep time ( approximately 8 h) in the newborn to approximately 15% of total sleep time (approximately 1 h) in the adult, and this decrease takes place mainly between birth and the end of puberty. We hypothesize that without this developmental decrease in REM sleep drive, lifelong increases in REM sleep drive may ensue. In the rat, the developmental decrease in REM sleep occurs 10-30 days after birth, declining from >70% of total sleep time in the newborn to the adult level of approximately 15% of sleep time during this period. Rats at 12-21 days of age were anesthetized with ketamine and decapitated, and brain stem slices were cut for intracellular recordings. We found that excitatory responses of pedunculopontine nucleus (PPN) neurons to N-methyl-D-aspartic acid decrease, while responses to kainic acid increase, over this critical period. During this developmental period, inhibitory responses to serotonergic type 1 agonists increase but responses to serotonergic type 2 agonists do not change. The results suggest that as PPN neurons develop, they are increasingly activated by kainic acid and increasingly inhibited by serotonergic type 1 receptors. These processes may be related to the developmental decrease in REM sleep. Developmental disturbances in each of these systems could induce differential increases in REM sleep drive, accounting for the postpubertal onset of a number of different disorders manifesting increases in REM sleep drive. Examination of modulation by PPN projections to ascending and descending targets revealed the presence of common signals modulating ascending arousal-related functions and descending postural/locomotor-related functions.


Assuntos
Neurônios/fisiologia , Núcleo Tegmental Pedunculopontino/fisiologia , Sono REM/fisiologia , Potenciais de Ação/fisiologia , Animais , Nível de Alerta/fisiologia , Estimulação Elétrica , Feminino , Técnicas In Vitro , Movimento/fisiologia , Núcleo Tegmental Pedunculopontino/citologia , Gravidez , Ratos , Ratos Sprague-Dawley , Receptores de Ácido Caínico/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Receptores de Serotonina/fisiologia
20.
Neurology ; 61(5): 686-9, 2003 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-12963764

RESUMO

Microglia, the brain's intrinsic macrophages, bind (R)-PK11195 when activated by neuronal injury. The authors used [11C](R)-PK11195 PET to localize in vivo microglial activation in patients with multiple system atrophy (MSA). Increased [11C](R)-PK11195 binding was primarily found in the dorsolateral prefrontal cortex, putamen, pallidum, pons, and substantia nigra, reflecting the known distribution of neuropathologic changes in MSA. Providing an indicator of disease activity, [11C](R)-PK11195 PET can thus be used to characterize the in vivo neuropathology of MSA.


Assuntos
Isoquinolinas , Microglia/diagnóstico por imagem , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Idoso , Radioisótopos de Carbono , Humanos , Masculino , Pessoa de Meia-Idade
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