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1.
J Behav Med ; 45(2): 318-323, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34718912

RESUMO

Physical activity (PA) is suggested as an easily accessible adjunctive lifestyle intervention for insomnia. It is not clear if PA is equally beneficial across different levels of insomnia severity. The current study examined the relationship between daily PA (steps) and sleep (duration, efficiency, and quality) across the spectrum of insomnia severity. Multilevel models estimated day-to-night relationships between PA and sleep, and if insomnia severity moderated these relationships. Days with greater PA were associated with nights with longer sleep duration. This was moderated by insomnia severity; PA was associated with longer sleep that night in participants with mild insomnia and associated with less sleep in those with severe insomnia. PA was not associated with sleep efficiency or quality. PA is potentially an easily accessible and impactful intervention to promote sleep duration in participants who are experiencing less severe sleep disturbance. More complex, resource-intensive interventions may be needed as insomnia severity increases.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Transtornos do Sono-Vigília , Veteranos , Exercício Físico , Humanos , Sono
2.
Annu Rev Anim Biosci ; 12: 209-332, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-37931139

RESUMO

Selective breeding of resilient organisms is an emerging topic in marine conservation. It can help us predict how species will adapt in the future and how we can help restore struggling populations effectively in the present. Scleractinian corals represent a potential tractable model system given their widescale phenotypic plasticity across fitness-related traits and a reproductive life history based on mass synchronized spawning. Here, I explore the justification for breeding in corals, identify underutilized pathways of acclimation, and highlight avenues for quantitative targeted breeding from the coral host and symbiont perspective. Specifically, the facilitation of enhanced heat tolerance by targeted breeding of plasticity mechanisms is underutilized. Evidence from theoretical genetics identifies potential pitfalls, including inattention to physical and genetic characteristics of the receiving environment. Three criteria for breeding emerge from this synthesis: selection from warm, variable reefs that have survived disturbance. This information will be essential to protect what we have and restore what we can.


Assuntos
Antozoários , Aquecimento Global , Animais , Adaptação Fisiológica , Antozoários/genética , Fenótipo , Reprodução
3.
Clin Exp Immunol ; 171(2): 117-23, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23286938

RESUMO

Recent studies analysing immunogenetics and immune mechanisms controlling susceptibility to chronic bacterial infection in bronchiectasis implicate dysregulated immunity in conjunction with chronic bacterial infection. Bronchiectasis is a structural pathological end-point with many causes and disease associations. In about half of cases it is termed idiopathic, because it is of unknown aetiology. Bronchiectasis is proposed to result from a 'vicious cycle' of chronic bacterial infection and dysregulated inflammation. Paradoxically, both immune deficiency and excess immunity, either in the form of autoimmunity or excessive inflammatory activation, can predispose to disease. It appears to be a part of the spectrum of inflammatory, autoimmune and atopic conditions that have increased in prevalence through the 20th century, attributed variously to the hygiene hypothesis or the 'missing microbiota'. Immunogenetic studies showing a strong association with human leucocyte antigen (HLA)-Cw*03 and HLA-C group 1 homozygosity and combinational analysis of HLA-C and killer immunoglobulin-like receptors (KIR) genes suggests a shift towards activation of natural killer (NK) cells leading to lung damage. The association with HLA-DR1, DQ5 implicates a role for CD4 T cells, possibly operating through influence on susceptibility to specific pathogens. We hypothesize that disruption of the lung microbial ecosystem, by infection, inflammation and/or antibiotic therapy, creates a disturbed, simplified, microbial community ('disrupted microbiota') with downstream consequences for immune function. These events, acting with excessive NK cell activation, create a highly inflammatory lung environment that, in turn, permits the further establishment and maintenance of chronic infection dominated by microbial pathogens. This review discusses the implication of these concepts for the development of therapeutic interventions.


Assuntos
Infecções Bacterianas/imunologia , Bronquiectasia/imunologia , Pulmão/microbiologia , Metagenoma/imunologia , Animais , Infecções Bacterianas/complicações , Bronquiectasia/microbiologia , Bronquiectasia/prevenção & controle , Linfócitos T CD4-Positivos/imunologia , Doença Crônica , Predisposição Genética para Doença , Antígenos HLA-C/genética , Antígenos HLA-C/imunologia , Humanos , Células Matadoras Naturais/imunologia , Pulmão/imunologia , Pneumopatias/imunologia , Pneumopatias/microbiologia , Consórcios Microbianos , Polimorfismo Genético , Receptores KIR/genética , Receptores KIR/imunologia
4.
Nat Commun ; 13(1): 1543, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351901

RESUMO

Finding coral reefs resilient to climate warming is challenging given the large spatial scale of reef ecosystems. Methods are needed to predict the location of corals with heritable tolerance to high temperatures. Here, we combine Great Barrier Reef-scale remote sensing with breeding experiments that estimate larval and juvenile coral survival under exposure to high temperatures. Using reproductive corals collected from the northern and central Great Barrier Reef, we develop forecasting models to locate reefs harbouring corals capable of producing offspring with increased heat tolerance of an additional 3.4° heating weeks (~3 °C). Our findings predict hundreds of reefs (~7.5%) may be home to corals that have high and heritable heat-tolerance in habitats with high daily and annual temperature ranges and historically variable heat stress. The locations identified represent targets for protection and consideration as a source of corals for use in restoration of degraded reefs given their potential to resist climate change impacts and repopulate reefs with tolerant offspring.


Assuntos
Antozoários , Termotolerância , Animais , Antozoários/genética , Mudança Climática , Recifes de Corais , Ecossistema
5.
Biol Open ; 9(1)2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31915210

RESUMO

The rate of coral reef degradation from climate change is accelerating and, as a consequence, a number of interventions to increase coral resilience and accelerate recovery are under consideration. Acropora spathulata coral colonies that survived mass bleaching in 2016 and 2017 were sourced from a bleaching-impacted and warmer northern reef on the Great Barrier Reef (GBR). These individuals were reproductively crossed with colonies collected from a recently bleached but historically cooler central GBR reef to produce pure and crossbred offspring groups (warm-warm, warm-cool and cool-warm). We tested whether corals from the warmer reef produced more thermally tolerant hybrid and purebred offspring compared with crosses produced with colonies sourced from the cooler reef and whether different symbiont taxa affect heat tolerance. Juveniles were infected with Symbiodinium tridacnidorum, Cladocopium goreaui and Durusdinium trenchii and survival, bleaching and growth were assessed at 27.5°C and 31°C. The contribution of host genetic background and symbiont identity varied across fitness traits. Offspring with either both or one parent from the northern population exhibited a 13- to 26-fold increase in survival odds relative to all other treatments where survival probability was significantly influenced by familial cross identity at 31°C but not 27.5°C (Kaplan-Meier P=0.001 versus 0.2). If in symbiosis with D. trenchii, a warm sire and cool dam provided the best odds of juvenile survival. Bleaching was predominantly driven by Symbiodiniaceae treatment, where juveniles hosting D. trenchii bleached significantly less than the other treatments at 31°C. The greatest overall fold-benefits in growth and survival at 31°C occurred in having at least one warm dam and in symbiosis with D. trenchii Juveniles associated with D. trenchii grew the most at 31°C, but at 27.5°C, growth was fastest in juveniles associated with C. goreaui In conclusion, selective breeding with warmer GBR corals in combination with algal symbiont manipulation can assist in increasing thermal tolerance on cooler but warming reefs. Such interventions have the potential to improve coral fitness in warming oceans.This article has an associated First Person interview with the first author of the paper.


Assuntos
Antozoários/crescimento & desenvolvimento , Antozoários/microbiologia , Mudança Climática , Simbiose , Temperatura , Termotolerância , Aclimatação , Animais , Dinoflagellida , Temperatura Alta , Oceanos e Mares , Seleção Artificial
6.
Ann Rheum Dis ; 67(7): 991-7, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17947303

RESUMO

OBJECTIVE: For patients with systemic vasculitis (SV) refractory to conventional therapy, new treatment strategies aimed at aggressive induction of remission and relapse prevention are being sought. We herein report our single-centre experience in treating four patients with refractory SV employing non-myeloablative autologous haematopoietic stem cell transplantation (HSCT). METHODS: Four patients with refractory SV (two with neurovascular Behcet disease, one with neurovascular Sjögren syndrome, and one with Wegener granulomatosis) were involved in an Institutional Review Board (IRB) and US Food and Drug Administration (FDA) approved phase I clinical trial of high dose chemotherapy and autologous HSCT. Peripheral blood stem cells were mobilised with cyclophosphamide (Cy) and granulocyte-colony stimulating factor (G-CSF). Conditioning regimen consisted of Cy 200 mg/kg and rabbit anti-thymocyte globulin 5.5 mg/kg intravenously (iv). RESULTS: All four patients tolerated HSCT well without transplant related mortality or any significant toxicity. At median follow-up of 28 (range 22-36) months all patients were alive. Three patients (one with Behcet disease, one with Sjögren syndrome, and one with Wegener granulomatosis) entered a sustained remission at 6, 6 and 24 months, respectively, after transplant. They had significant decrease in disease activity and disease or treatment related damage, as measured by the Birmingham Vasculitis Activity Score and Vasculitis Damage Index, respectively. All three patients who achieved remission discontinued immunosuppressive therapy at the time of transplant and have not required treatment since. One patient with Behcet disease and positive for human leukocyte antigen (HLA)-B51 has not improved after HSCT. CONCLUSION: We suggest non-myeloablative autologous HSCT is an alternative therapy for select patients with SV refractory to conventional immunosuppressive therapies.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Vasculite/terapia , Adulto , Biomarcadores/sangue , Transfusão de Componentes Sanguíneos/métodos , Feminino , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Imunossupressores/uso terapêutico , Imageamento por Ressonância Magnética , Indução de Remissão , Índice de Gravidade de Doença , Condicionamento Pré-Transplante/métodos , Resultado do Tratamento , Vasculite/tratamento farmacológico
7.
Bone Marrow Transplant ; 40(1): 47-53, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17483845

RESUMO

Patients with cardiac dysfunction may be at increased risk of cardiac toxicity when undergoing hematopoietic stem cell transplantation (HSCT), which may preclude them from receiving this therapy. Cardiac dysfunction is, however, common in systemic lupus erythematosus (SLE) patients. While autologous HSCT (auto-HSCT) has been performed increasingly for SLE, its impact on cardiac function has not previously been evaluated. We, therefore, performed a retrospective analysis of SLE patients who had undergone auto-HSCT in our center to determine the prevalence of significant cardiac involvement, and the impact of transplantation on this. The records of 55 patients were reviewed, of which 13 were found to have abnormal cardiac findings on pre-transplant two-dimensional echocardiography or multi-gated acquisition scan: impaired left ventricular ejection fraction (LVEF) (n = 6), pulmonary hypertension (n = 5), mitral valve dysfunction (n = 3) and large pericardial effusion (n = 1). At a median follow-up of 24 months (8-105 months), there were no transplant-related or cardiac deaths. With transplant-induced disease remission, all patients with impaired LVEF remained stable or improved; while three with symptomatic mitral valve disease similarly improved. Elevated pulmonary pressures paralleled activity of underlying lupus. These data suggest that auto-HSCT is feasible in selected patients with lupus-related cardiac dysfunction, and with control of disease activity, may improve.


Assuntos
Cardiopatias/complicações , Doenças das Valvas Cardíacas/terapia , Transplante de Células-Tronco Hematopoéticas , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/terapia , Disfunção Ventricular/terapia , Ciclofosfamida/uso terapêutico , Filgrastim , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Cardiopatias/diagnóstico por imagem , Cardiopatias/terapia , Doenças das Valvas Cardíacas/diagnóstico por imagem , Mobilização de Células-Tronco Hematopoéticas/métodos , Humanos , Lúpus Eritematoso Sistêmico/mortalidade , Cintilografia , Proteínas Recombinantes , Estudos Retrospectivos , Taxa de Sobrevida , Transplante Autólogo , Disfunção Ventricular/diagnóstico por imagem
8.
Bone Marrow Transplant ; 39(6): 317-29, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17277794

RESUMO

Peripheral blood stem cells (PBSC) were mobilized in 130 patients with autoimmune diseases undergoing autologous hematopoietic stem cell transplantation using cyclophosphamide 2 g/m(2) and either granulocyte colony-stimulating factor (G-CSF) 5 mcg/kg/day (for systemic lupus erythematosus (SLE) and secondary progressive multiple sclerosis, SPMS) or G-CSF 10 mcg/kg/day (for relapsing remitting multiple sclerosis (RRMS), Crohn's disease (CD), systemic sclerosis (SSc), and other immune-mediated disorders). Mobilization-related mortality was 0.8% (one of 130) secondary to infection. Circulating peripheral blood (PB) CD34(+) cells/microl differed significantly by disease. Collected CD34(+) cells/kg/apheresis and overall collection efficiency was significantly better using Spectra apheresis device compared to the Fenwall CS3000 instrument. Patients with SLE and RRMS achieved the lowest and the highest CD34(+) cell yields, respectively. Ex vivo CD34(+) cell selection employing Isolex 300iv2.5 apparatus was significantly more efficient compared to CEPRATE CS device. Circulating PB CD34(+) cells/microl correlated positively with initial CD34(+) cells/kg/apheresis and enriched product CD34(+) cells/kg. Mean WBC and platelet engraftment (ANC>0.5 x 10(9)/l and platelet count >20 x 10(9)/l) occurred on days 9 and 11, respectively. Infused CD34(+) cell/kg dose showed significant direct correlation with faster white blood cell (WBC) and platelet engraftment. When adjusted for CD34(+) cell/kg dose, patients treated with a myeloablative regimen had significantly slower WBC and platelet recovery compared to non-myeloablative regimens.


Assuntos
Antígenos CD34/isolamento & purificação , Doenças Autoimunes/sangue , Mobilização de Células-Tronco Hematopoéticas , Leucaférese/instrumentação , Transplante de Células-Tronco de Sangue Periférico , Adolescente , Adulto , Doenças Autoimunes/terapia , Feminino , Humanos , Leucaférese/métodos , Masculino , Pessoa de Meia-Idade , Transplante Autólogo
9.
Neurobiol Aging ; 8(3): 225-32, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3600953

RESUMO

The effects of providing 50% of normal feed intake for 10 weeks followed by 16 weeks of ad lib feeding on estrous cycles and mammary tumor incidence were studied in female rats initially 4 months and 15-16 months old. Initially all young rats exhibited regular or irregular estrous cycles and only about 41% of the older rats cycled regularly or irregularly; the remainder of the older rats did not cycle. During underfeeding, both the young and older rats lost body weight and ceased to cycle. After refeeding 100% of both young and old rats resumed cycling, the young rats for a much longer period than the old rats, and more of both groups continued to cycle than their ad lib-fed controls. Upon refeeding, the young and old rats reached the body weights of the ad lib-fed controls in about 3 weeks. Mammary tumors were initially present only in old rats and regressed during underfeeding; they rapidly reached control size upon refeeding. Plasma PRL levels declined during underfeeding but rebounded to higher than control values upon refeeding in both young and old rats. In young but not in old rats, plasma LH levels fell during underfeeding but returned to control values upon refeeding. These results demonstrate that a relatively short period of underfeeding, followed by refeeding, can delay the decline in reproductive cycles in young rats and reinitiate estrous cycles in older rats. These effects appear to be mediated via the neuroendocrine system.


Assuntos
Envelhecimento/fisiologia , Estro/fisiologia , Privação de Alimentos/fisiologia , Neoplasias Mamárias Experimentais/epidemiologia , Animais , Peso Corporal , Feminino , Crescimento , Hormônio Luteinizante/sangue , Prolactina/sangue , Ratos , Ratos Endogâmicos
10.
Neurobiol Aging ; 11(6): 625-30, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2280806

RESUMO

In order to clarify whether pituitary enlargement influences the secretory patterns of growth hormone (GH) and thyrotropin (TSH) in old rats, we studied the correlation between pituitary weight and plasma levels of GH and TSH in Sprague-Dawley rats of different age and sex. Young female (3-4 months; YF), old female (25 months; OF), and senescent female (33-35 months; SF) rats and young male (3-4 months; YM) and old male (24-26 months; OM) rats carrying chronic intraatrial cannulas were used. Sequential blood samples were removed through the cannulas while the animals remained conscious and undisturbed. Plasma TSH and GH as well as serum thyroxine (T4) and triiodothyronine (T3) were measured by radioimmunoassay. At two years of age, both males and females showed a consistent decline in GH pulse amplitude without change in trough levels. By 33-35 months of age, females showed a reversal in the previous pattern of change for GH secretion: pulse amplitude, trough levels, and mean plasma GH increased significantly with respect to the old females. The correlation between mean plasma GH and anterior pituitary (AP) weight was positive and significant (p less than 0.01) for females but nonsignificant for males. Old and senescent rats showed significantly lower serum T4, but not T3, than young animals while plasma TSH increased with age in both sexes.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Envelhecimento/fisiologia , Hormônio do Crescimento/metabolismo , Tireotropina/metabolismo , Animais , Feminino , Masculino , Tamanho do Órgão , Adeno-Hipófise/anatomia & histologia , Adeno-Hipófise/fisiologia , Radioimunoensaio , Ratos , Ratos Endogâmicos , Fatores Sexuais , Tiroxina/metabolismo , Tri-Iodotironina/metabolismo
11.
Mech Ageing Dev ; 41(3): 219-27, 1987 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3431174

RESUMO

Thymosin fraction 5 (TF-5), a partially purified thymic preparation, has been previously shown to have luteinizing hormone-releasing hormone (LH-RH)-releasing activity in perfused rat hypothalamus as well as in vivo stimulatory effect on the pituitary-adrenal axis in prepubertal monkeys. We report here the effect of TF-5 on the TSH-thyroid axis in young (3 months) and old (25 months) Sprague-Dawley male rats. Conscious free-moving animals carrying an indwelling atrial cannula received a single dose of 5 mg/kg body wt. of either bovine serum albumin (BSA) or TF-5 via the cannula. In the young rats, TF-5 induced a marked reduction of plasma thyrotropin (TSH) which was significantly greater than the normal circadian decline observed in the BSA-treated controls. The old males displayed high basal levels of TSH which showed no circadian rhythmicity, and did not respond to TF-5. Thyroxine (T4), triiodothyronine (T3), corticosterone, and prolactin levels were not affected by TF-5 at the dose levels tested. The old rats had significantly lower basal levels of T4, but not T3, than their young counterparts. The synthetic peptides thymosin alpha-1 and serum thymic factor, which are components of TF-5, had no effect on the above hormones when injected in doses up to 5 micrograms/kg body wt. Acute thymectomy in 3-month-old males induced a significant increase in basal levels of TSH without affecting plasma T4 or T3. These results suggest that the thymus has an inhibitory action on TSH in the rat, which is not mediated by the thyroid gland.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Envelhecimento/fisiologia , Timosina/análogos & derivados , Tireotropina/antagonistas & inibidores , Animais , Ritmo Circadiano , Corticosterona/sangue , Masculino , Prolactina/sangue , Ratos , Ratos Endogâmicos , Timosina/farmacologia , Timo/fisiologia , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
12.
Mech Ageing Dev ; 49(2): 119-28, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2677534

RESUMO

There is increasing evidence that the neuroendocrine system is responsive to hormonal signals generated by the immune system. Thus, interleukin-1, hepatocyte stimulating factor and thymosin have been shown to stimulate adrenocorticotropin, beta-endorphin and luteinizing hormone secretion. We report here that homeostatic thymus hormone (HTH), a well-characterized thymic preparation, reduces plasma thyrotropin (TSH) and growth hormone (GH) in young (3 months) Sprague-Dawley male rats, but fails to do so (TSH) or has a significantly weaker effect (GH) in old (26 months) animals. Young and old conscious, free-moving rats carrying an indwelling atrial cannula received the substances to be tested via the cannulas. Plasma samples were taken every 30 min for 5 h and hormones were measured by RIA. In the young rats, HTH (8 mg/kg body wt) induced a marked reduction in plasma TSH which was significantly greater than the normal circadian decline observed in saline-injected young controls. The old rats displayed high basal levels of TSH which showed no circadian rhythmicity and did not respond to HTH. Plasma thyroxine (T4) showed a significant age-related reduction but was not affected by HTH. The above dose of HTH significantly reduced plasma GH in young and old rats, but the effect was greater in the young animals. Mean basal levels of plasma GH were significantly lower in old than in young rats. The present results suggest that HTH, whose production by the thymus is known to be stimulated by TSH and GH, is involved in an inhibitory feedback loop regulating plasma TSH and GH in young rats. Our data also suggest an age-related desensitization of the TSH and GH systems to thymic influence in this species.


Assuntos
Envelhecimento/fisiologia , Hormônio do Crescimento/sangue , Homeostase , Hormônios do Timo/fisiologia , Tireotropina/sangue , Animais , Ratos , Hormônios do Timo/farmacologia
13.
Psychol Bull ; 114(2): 296-322, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8416034

RESUMO

Contemporary findings reveal that autonomic control of dually innervated visceral organs does not lie along a single continuum extending from parasympathetic to sympathetic dominance. Rather, a bivariate autonomic space bounded by sympathetic and parasympathetic axes is the minimal representation necessary to capture the modes of autonomic control. We here empirically instantiate a quantitative bivariate model for the chronotropic control of the heart in humans. This model provides a more comprehensive characterization of psychophysiological response than simple measures of end-organ state and permits a differentiation of behavioral states and processes that would otherwise remain obscure. The model also illuminates and subsumes general principles such as the law of initial values and reveals a fundamental physiological rationale for the selection of heart period over heart rate as a metric for cardiac chronotropy. The present article also considers strategies for psychophysiological investigations within the autonomic space model, the limitations of these methods, and analytical tools for assessing their validity.


Assuntos
Nível de Alerta/fisiologia , Sistema Nervoso Autônomo/fisiologia , Coração/inervação , Adulto , Animais , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Sistema Nervoso Parassimpático/fisiologia , Psicofisiologia , Sistema Nervoso Simpático/fisiologia , Nervo Vago/fisiologia
14.
Psychol Rev ; 98(4): 459-87, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1660159

RESUMO

Contemporary findings reveal that the multiple modes of autonomic control do not lie along a single continuum extending from parasympathetic to sympathetic dominance but rather distribute within a 2-dimensional space. The physiological origins and empirical documentation for the multiple modes of autonomic control are considered. Then a formal 2-dimensional conception of autonomic space is proposed, and a quantitative model for its translation into a functional output surface is derived. It is shown that this model (a) accounts for much of the error variance that has traditionally plagued psychophysiological studies, (b) subsumes psychophysiological principles such as the law of initial values, (c) gives rise to formal laws of autonomic constraint, and (d) has fundamental implications for the direction and interpretation of a wide array of psychophysiological studies.


Assuntos
Nível de Alerta/fisiologia , Sistema Nervoso Autônomo/fisiologia , Transmissão Sináptica/fisiologia , Animais , Humanos , Modelos Neurológicos , Sistema Nervoso Parassimpático/fisiologia , Sistema Nervoso Simpático/fisiologia
15.
Exp Gerontol ; 25(5): 447-57, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2257891

RESUMO

The effects of a 50% reduction in normal food intake for a period of 10 weeks were measured on secretion of growth hormone (GH), thyroxine (T4), and triiodothyronine (T3) in 5 1/2-6 1/2-month old, 13 1/2-month-old, and 17 1/2-18 1/2-month-old male rats. In full-fed controls, GH, T3, and T4 were lower in the old and middle-aged than in the young rats. By the 10th week of underfeeding, GH, T3, and T4 were reduced in all age groups, but the decrease in T3 and T4 in the middle-aged and old rats was greater than in the young rats. Pulses of GH ceased in all the underfed groups. Upon refeeding for 5 days, pulses of GH and levels of GH returned to full-fed control values in the young and middle-aged but not in the old rats. T3 values in the young and middle-aged rats returned to full-fed control levels, but remained below control levels in the old rats. T4 values reached control levels in all age groups upon refeeding. The differences in the response to underfeeding and refeeding by the middle-aged and old rats as compared to the young rats may be due to their initially lower secretion of GH and thyroid hormones and to the age-related decrease in neuroendocrine function.


Assuntos
Envelhecimento/metabolismo , Ingestão de Alimentos , Hormônio do Crescimento/metabolismo , Tiroxina/metabolismo , Tri-Iodotironina/metabolismo , Animais , Peso Corporal , Ingestão de Energia , Hormônio do Crescimento/sangue , Masculino , Radioimunoensaio , Ratos , Ratos Endogâmicos , Tiroxina/sangue , Tri-Iodotironina/sangue
16.
Bone Marrow Transplant ; 32 Suppl 1: S65-7, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12931246

RESUMO

Systemic sclerosis (SSc) is presumed to be an immune-mediated vasculopathy of unknown etiology. SSc is unresponsive to most immune-modulating therapies except for intravenous cyclophosphamide, which is reported to demonstrate some benefit. We, therefore, dose-escalated cyclophosphamide to 200 mg/kg and added rabbit ATG 7.5 mg/kg along with infusion of unselected hematopoietic stem cells to minimize the cytopenic interval. Engraftment occurred rapidly (day 8) with minimal unexpected toxicity, no infections, and unexpectedly rapid improvement in the modified Rodnan Skin Score.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Escleroderma Sistêmico/terapia , Soro Antilinfocitário/administração & dosagem , Ciclofosfamida/administração & dosagem , Sobrevivência de Enxerto , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/toxicidade , Neovascularização Fisiológica , Seleção de Pacientes , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/diagnóstico , Índice de Gravidade de Doença , Pele/patologia , Fatores de Tempo , Resultado do Tratamento
17.
Behav Neurosci ; 104(5): 751-62, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2244983

RESUMO

Heart rate (HR) and blood pressure responses to nonsignal auditory stimuli were measured in rats after saline or pharmacological blockade of the sympathetic or vagal innervation of the heart. HR responses to the low-intensity stimulus were predominantly deceleratory, whereas responses to the high-intensity stimulus were more notably acceleratory. Both stimuli elicited a biphasic pressor-depressor response, although potential baroreflex influences accounted for only a small proportion of the HR response variance. Deceleratory responses to the low-intensity stimulus were eliminated by scopolamine and thus appeared to be predominantly of vagal origin. Acceleratory response to the high-intensity stimulus appeared to be mediated primarily by sympathetic activation because it was substantially attenuated by the beta 1 antagonist atenolol. Furthermore, HR responses to the low-intensity stimulus appeared to reflect coactivation of both sympathetic and vagal systems.


Assuntos
Nível de Alerta/fisiologia , Atenção/fisiologia , Sistema Nervoso Autônomo/fisiologia , Animais , Nível de Alerta/efeitos dos fármacos , Atenolol/farmacologia , Sistema Nervoso Autônomo/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Relação Dose-Resposta a Droga , Coração/inervação , Frequência Cardíaca/fisiologia , Masculino , Pressorreceptores/fisiologia , Ratos , Ratos Endogâmicos , Reflexo/fisiologia , Escopolamina/farmacologia , Sistema Nervoso Simpático/fisiologia , Nervo Vago/fisiologia
18.
J Am Med Inform Assoc ; 4(6): 436-41, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9391931

RESUMO

Kurzweil Applied Intelligence received a research grant from the National Institute of Standards and Technology (NIST) Advanced Technology Program to develop a prototype voice-enabled, structured medical reporting system. In typical usage, the physician dictates to the system, which then uses automatic speech recognition and medical knowledge bases to produce a structured report. This report can then be formatted and viewed on a computer screen, stored in databases of patient information, transmitted to other systems, used to support outcome studies, or viewed on a Web browser. The output reports are structured according to two standard, platform-independent formats: SGML and CORBA. These formats represent the data in a way that can be read by both computers and humans, and efficiently communicated to a wide range of databases and communications protocols.


Assuntos
Sistemas Computadorizados de Registros Médicos/normas , Interface Usuário-Computador , Armazenamento e Recuperação da Informação/normas , Linguagens de Programação , Voz
19.
Behav Brain Res ; 62(1): 11-20, 1994 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-7917029

RESUMO

Effects of the benzodiazepine receptor (BZR) partial inverse agonist FG 7142 (FG) on basal and reactive cardiovascular measures were examined in freely moving rats. FG (8 mg/kg) modestly increased basal heart period, but had no effects on basal blood pressure. More notably, however, FG augmented the cardioacceleratory response to an auditory stimulus relative to vehicle controls. Selective blockade of sympathetic (atenolol, 1 mg/kg) or parasympathetic (scopolamine methylnitrate, 0.1 mg/kg) effects on the heart under control conditions revealed that the stimulus-evoked cardiac response originated from a concurrent (reciprocal) sympathetic activation and vagal withdrawal. Following FG pretreatment, both atenolol and scopolamine blocked the cardioacceleratory response to the auditory stimulus. Thus, although FG minimally increased basal heart period, FG significantly enhanced a reactive cardioacceleration. More importantly, these results demonstrate that the cardiovascular effects of BZR inverse agonists are more fully characterized by an assessment of both tonic and reactive cardiovascular responses.


Assuntos
Depressores do Apetite/farmacologia , Nível de Alerta/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Carbolinas/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Receptores de GABA-A/efeitos dos fármacos , Estimulação Acústica , Animais , Atenolol/farmacologia , Relação Dose-Resposta a Droga , Masculino , N-Metilescopolamina , Sistema Nervoso Parassimpático/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Derivados da Escopolamina/farmacologia , Sistema Nervoso Simpático/efeitos dos fármacos
20.
J Hosp Infect ; 45(1): 1-10, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10833336

RESUMO

Small round structured viruses (SRSVs, Norwalk-like viruses, NLVs) are the most common cause of outbreaks of gastro-enteritis in hospitals and also cause outbreaks in other settings such as schools, hotels, nursing homes and cruise ships. Hospital outbreaks often lead to ward closure and major disruption in hospital activity. Outbreaks usually affect both patients and staff, sometimes with attack rates in excess of 50%. For this reason, staff shortages can be severe, particularly if several wards are involved at the same time. SRSVs may be spread by several routes: faecal-oral; vomiting/aerosols; food and water. Viruses may be introduced into the ward environment by any of these routes and then propagated by person-to-person spread. In an outbreak setting, the diagnosis can usually be made rapidly and confidently on clinical and epidemiological grounds, particularly if vomiting is a prominent symptom. By the time an SRSV outbreak has been recognized at ward level, most susceptible individuals will have been exposed to the virus and infection control efforts must prioritize the prevention of spread of infection to other clinical areas bycontainment of infected/exposed individuals (especially the prevention of patient and staff movements to other areas), hand-hygiene and effective environmental decontamination. This report of the Public Health Laboratory Service Viral Gastro-enteritis Working Group reviews the epidemiology of outbreaks of infection due to SRSVs and makes recommendations for their management in the hospital setting. The basic principles which underpin these recommendations will also be applicable to the management of some community-based institutional outbreaks.


Assuntos
Infecções por Caliciviridae/prevenção & controle , Surtos de Doenças/prevenção & controle , Gastroenterite/prevenção & controle , Controle de Infecções/métodos , Infecções por Caliciviridae/diagnóstico , Comunicação , Surtos de Doenças/economia , Desinfecção , Gastroenterite/diagnóstico , Gastroenterite/microbiologia , Humanos , Controle de Infecções/economia
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