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1.
BMC Prim Care ; 23(1): 220, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-36045339

RESUMO

BACKGROUND: Type 2 diabetes (T2D) and coronary artery disease (CAD) are chronic illnesses where adherence to a healthy lifestyle is crucial. If organisational and cultural factors are well managed, Peer support programs (PSP) can improve self-management, quality of life, and health outcomes. In preparation for launching a PSP, we surveyed family doctors (FD) about their attitudes toward such a program and about potential barriers, and facilitators. METHODS: In March 2020 we surveyed 896 FDs from five university teaching practice networks in North-Rhine Westphalia, Germany, via an anonymous web-based survey. The questionnaire addressed details of PSPs, including suitable patients and FDs'role. Data were analysed using descriptive and inferential statistics; qualitative material underwent content analysis by two researchers. RESULTS: A total of 165 FDs responded (response rate: 18.4%), 97% were practice owners. Respondents viewed PSPs positively (T2D: 92.0%, CAD 89.9%), especially for patients with poor self-structuring (82.7%), low motivation (76.3%) and few social contacts (67.6%). On average, FDs were able to identify 4.0 ± 3.2 patients as potential group leaders. Major facilitators reported included motivation by peers (92.5%), exercise (79.1%), and social contacts (70.1%). Waning interest over time (73.1%) and poor motivation (70.9%) were considered barriers. The majority of FDs would recommend PSPs to their patients (89.5%). They considered such a program a valuable addition to current care (79.7%). The percentage of FDs' who expected long-term benefits for their workload was relatively low (37.6%). CONCLUSIONS: In an exploratory survey among German FDs on PSPs, respondents viewed PSPs as a valuable add-on for T2D and CAD patients, while not expecting a positive impact on their workload. Communication with FDs on PSPs may need to highlight anticipated implementation outcomes such as benefits of PSPs to the practice.


Assuntos
Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Doença da Artéria Coronariana/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Humanos , Médicos de Família/educação , Qualidade de Vida , Inquéritos e Questionários
5.
Anaesthesia ; 74(8): 1057-1060, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31025706

RESUMO

More than one million peri-operative patients die each year. Thus, small improvements in peri-operative care may save thousands of lives. However, clinicians need confidence in the robustness of trial findings. The Fragility Index may complement frequentist analysis and provide quantitative assessment of robustness. We searched MEDLINE for peri-operative critical care randomised controlled trials that reported a statistically significant difference in mortality. We identified 46 trials with 37,347 participants. The median (IQR [range]) Fragility Index was 2 (1-3 [0-49]). Eleven trials had a Fragility Index of zero (changing from the Chi-square test to Fisher's exact test removed significance) and seven trials had a Fragility Index of 1. Only 23/46 trials had a Fragility Index greater than the number of patients lost to follow-up. There was a strong positive correlation between the Fragility Index and: the number of participants, R2  = 0.97, p < 0.0001; the number of centres that recruited participants, R2  = 0.96, p < 0.0001; the number of nations that recruited participants, R2  = 0.93, p < 0.0001; and the number of deaths, R2  = 0.97, p < 0.0001. As measured by the Fragility Index, the effect of peri-operative interventions on mortality in individual randomised controlled trials are not robust.


Assuntos
Cuidados Críticos , Assistência Perioperatória , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Adulto , Humanos , Mortalidade
6.
Anesth Analg ; 128(5): 971-980, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30896601

RESUMO

Awake fiberoptic intubation is one of the recommended strategies for surgical patients with anticipated difficult airway, especially when concurrent difficult ventilation is expected. We performed the first systematic review of randomized controlled trials assessing different protocols for awake fiberoptic intubation in anticipated difficult airway, including studies investigating elective awake fiberoptic intubation for scheduled surgery; randomized controlled trials comparing different methods for performing awake fiberoptic intubation; and adult patients with anticipated difficult airway. We excluded studies in the nonoperating theater settings, randomized controlled trials comparing awake fiberoptic intubation with other techniques, and studies based on simulation. Primary outcomes were success rate and death; secondary outcomes were major adverse events. Thirty-seven randomized controlled trials evaluating 2045 patients and 4 areas were identified: premedication, local anesthesia, sedation, and ancillary techniques to facilitate awake fiberoptic intubation. Quality of evidence was moderate-low and based on small-sampled randomized controlled trials. Overall, 12 of 2045 intubation failures (0.59%) and 7 of 2045 severe adverse events (0.34%) occurred, with no permanent consequences or death. All evaluated methods to achieve local anesthesia performed similarly well. No differences were observed in success rate with different sedatives. Dexmedetomidine resulted in fewer desaturation episodes compared to propofol and opioids with or without midazolam (relative risk, 0.51 [95% CI, 0.28-0.95]; P = .03); occurrence of desaturation was similar with remifentanil versus propofol, while incidence of apnoea was lower with sevoflurane versus propofol (relative risk, 0.43 [95% CI, 0.22-0.81]; P = .01). A high degree of efficacy and safety was observed with minimal differences among different protocols; dexmedetomidine might offer a better safety profile compared to other sedatives.


Assuntos
Protocolos Clínicos , Tecnologia de Fibra Óptica , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/métodos , Salas Cirúrgicas , Analgésicos Opioides/uso terapêutico , Anestesia Local , Dexmedetomidina/uso terapêutico , Humanos , Hipnóticos e Sedativos , Midazolam/uso terapêutico , Segurança do Paciente , Propofol/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco , Resultado do Tratamento , Vigília
7.
J Crit Care ; 48: 414-417, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30317050

RESUMO

PURPOSE: It is uncertain whether, in critical care medicine, non-blinded trials are associated with a bias toward a different effect size. The aim of our study was to assess if conducting non-blinded/open label studies leads to greater effect size than blinded studies, and to provide an estimate of the weight of this difference. MATERIALS AND METHODS: We systematically searched all papers published in peer-reviewed journals between January 2000 and December 2015, dealing with non surgical interventions in critically ill adults and reporting a statistically significant difference in mortality. We assessed the number needed to treat (NNT) of each trial to estimate the treatment effect size and we divided studies into non-blinded, single-blinded and double-blinded. We searched for correlation between the treatment effect size and blinding, and adjusted for the other trial variables. RESULTS: We identified 119 critically ill randomized controlled trials. Of these, 69 studies were non-blinded and 50 were blinded. The median NNT in non-blinded studies was 5 [IQR 4-7] while it was 7 [IQR 5-7] in the blinded studies (p < .001). CONCLUSIONS: The NNT for blinded studies is 40% higher than for unblinded studies. This should be taken into account when planning and interpreting the findings of non-blinded studies performed in critically ill settings.


Assuntos
Ensaios Clínicos como Assunto/métodos , Cuidados Críticos , Projetos de Pesquisa , Viés , Humanos
8.
J Affect Disord ; 193: 391-404, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26802316

RESUMO

Postpartum depression, now termed perinatal depression by the DSM-5, is a clinically relevant disorder reaching 15% of incidence. Although it is quite frequent and associated with high social dysfunction, only recently its underpinning biological pathways have been explored, while multiple and concomitant risk factors have been identified (e.g. psychosocial stress). Peripartum depression usually has its onset during the third trimester of pregnancy or in the postpartum, being one of the most common medical complications in new mothers. Purpose of the present review is to summarize the state of art of biological biomarkers involved in the pathogenesis of perinatal depression, in view of the fact that suboptimal prenatal milieu can induce permanent damage in subsequent offspring life and have a negative impact on mother-child relationship. Furthermore, parents' biological changes due to medical/psychiatric disorders or stress exposure could influence offspring life: a concept known as 'intergenerational transmission', acting by variations into gametes and the gestational uterine environment. Given the evidence that perinatal mental disorders involve risks for the mother and offspring, the search for reliable biomarkers in high-risk mothers actually represents a medical priority to prevent perinatal depression.


Assuntos
Depressão Pós-Parto , Transtorno Depressivo Maior , Biomarcadores/metabolismo , Depressão Pós-Parto/genética , Depressão Pós-Parto/imunologia , Depressão Pós-Parto/metabolismo , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/imunologia , Transtorno Depressivo Maior/metabolismo , Feminino , Humanos , Gravidez
9.
Rehabilitation (Stuttg) ; 54(4): 240-4, 2015 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-26317839

RESUMO

OBJECTIVE: In Germany, the rehabilitative approaches towards patients with coronary artery events are not adequately sustainable despite the high costs. Both sustainability and cost effectiveness are the subjects of this 5-year analysis. METHODS: The study was initiated in 2004. One year recruiting phase was followed by 3 years aftercare with telephone as an intervention. This unicentric randomised controlled trial included 600 patients of rehabilitative aftercare (intervention group [IG] 271; control group [CG] 329). Data on (i) mortality, (ii) duration of retirement, (iii) type of retirement and (iv) status of retirement were obtained from the German Retirement Insurance.The analyses for cost-effectiveness are conducted for the intention-to-treat (ITT) approach. The general assessment basis of retirements (partial and full disability pensions) are average values for the year 2013 (year of the measurement). RESULTS: On the reporting date (31.12.2013), the values of the IG in part (early) retirement and full (early) retirement are higher than the CG (1.5 and 2.7%, n. s. and 7.4 and 13.4%, respectively n. s.). The same applies for mortality (8.1 and 9.4%, respectively n. s.).The savings through lower pension payments amount to € 1.55 million for the adjusted ITT approach. From this, € 130 080, which represents the cost of the aftercare (intervention), must be deducted. CONCLUSIONS: The results of the 5-year follow-up show that a part of pension payment could be reduced. The evidence of cost effectiveness, independently of the methodological approach, is strong. The saving potential is reached by half in both approaches.


Assuntos
Assistência ao Convalescente/economia , Doença da Artéria Coronariana/economia , Doença da Artéria Coronariana/reabilitação , Custos de Cuidados de Saúde/estatística & dados numéricos , Pensões/estatística & dados numéricos , Reabilitação/economia , Assistência ao Convalescente/estatística & dados numéricos , Doença da Artéria Coronariana/mortalidade , Análise Custo-Benefício/economia , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prevalência , Reabilitação/estatística & dados numéricos , Taxa de Sobrevida , Resultado do Tratamento
10.
Dtsch Med Wochenschr ; 139(8): 369-74, 2014 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-24519113

RESUMO

BACKGROUND AND OBJECTIVE: Type 2 diabetes and depression often appear together. Although health behaviour and risk factors partially explain this association, other potential mechanisms have yet to be elucidated. METHODS: Explorative literature research for reviews on the topic in PubMed. Additional key-word guided research for studies in PubMed and Cochrane Library employing the keywords "diabetes" AND "depression" in combination with identified relevant single aspects (MeSH-terms) for certain neuroendocrine alterations, neuropathological und neurobiochemestric changes as well as the role of antidepressants. RESULTS: There are no satisfying explanatory models for the complex interaction of both diseases concerning behavioural factors and pathophysiological changes. Currently there are only many single aspects of shared or interacting pathophysiology or behaviour conspicuity. CONCLUSION: The objective of this review is to summarize these aspects and their contributions to the interacting pathophysiology of the two diseases.


Assuntos
Transtorno Depressivo/epidemiologia , Transtorno Depressivo/fisiopatologia , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Comportamentos Relacionados com a Saúde , Estilo de Vida , Antidepressivos/efeitos adversos , Antidepressivos/uso terapêutico , Comorbidade , Estudos Transversais , Citocinas/sangue , Transtorno Depressivo/psicologia , Diabetes Mellitus Tipo 2/psicologia , Humanos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Células Secretoras de Insulina/fisiologia , Estresse Oxidativo/fisiologia , Fatores de Risco , Sistema Nervoso Simpático/fisiopatologia
11.
Eur J Clin Nutr ; 67(4): 366-70, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23462940

RESUMO

BACKGROUND: The aims of the study were: (i) to determine iodine status of schoolchildren living in northeast Italy; (ii) to assess dietary habits and iodine status and (iii) to investigate the level of knowledge concerning iodine sufficiency and ways to ameliorate iodine status. METHODS: One thousand three hundred seventy-five consecutive 12-13 year-old completed questionnaires collecting demographic data and information about the use of iodized salt and food frequency habits. Iodine concentration in urine samples (UIC) and in commercially available milk samples has been measured. RESULTS: The median UIC was found to be 81 µg/l (95% confidence interval (CI) 74-87); 40% of the subjects had an UIC of ≥ 100 µg/l. Iodine deficiency was prevalent in subjects living in hilly areas. Median iodine concentration in milk was 264 µg/l. Only the combined use of iodized salt plus daily milk normalized UIC, resulting into a median value of 108 µg/l. A logistic regression model confirmed independent associations between low UIC and low intake of milk, use of non-iodized salt and geographical location (P<0.0001). Only 45% of the subjects were aware of the importance of iodine. CONCLUSIONS: Northeast Italy is still characterized by mild iodine deficiency. An adequate iodine status was achieved only when iodized salt was combined with daily milk intake. The national iodine prophylaxis program has led to greater consumption of iodized salt and, it is now used in 60-70% of the Italian households. The low level of awareness highlights the need for public programs to promote knowledge and efforts to improve iodine status.


Assuntos
Comportamento Alimentar , Iodo/administração & dosagem , Iodo/deficiência , Leite/química , Cloreto de Sódio na Dieta/administração & dosagem , Adolescente , Animais , Criança , Feminino , Humanos , Iodo/urina , Itália/epidemiologia , Modelos Logísticos , Masculino , Estado Nutricional , Cloreto de Sódio na Dieta/urina , Estatísticas não Paramétricas , Inquéritos e Questionários
12.
Chem Senses ; 35(8): 647-54, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20530376

RESUMO

Mice recognize other mice by identifying chemicals that confer a molecular signature to urinary marks. Such molecules may be involved in species recognition, and previous behavioral studies have related divergence of sexual preference between 2 subspecies of the house mouse (Mus musculus musculus and Mus musculus domesticus) to urinary odors. To characterize the differences between odors of males of the 2 subspecies and their first-generation offspring, the urinary volatile molecules were examined via gas chromatography coupled to mass spectrometry. Seven molecules were present in the samples from mice of at least one group. Their quantity varied among groups: M. m. domesticus showed a quantitatively richer panel of odorants in their urine when compared with M. m. musculus. The hybrids showed a more complex picture that was not directly related to one or the other parental subspecies. These quantitative differences may contribute to the specificity of the odorant bouquet of the 2 subspecies.


Assuntos
Compostos Orgânicos Voláteis/urina , Animais , Europa (Continente) , Cromatografia Gasosa-Espectrometria de Massas/métodos , Masculino , Camundongos , Especificidade da Espécie
13.
Schmerz ; 24(4): 373-9, 2010 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-20490570

RESUMO

BACKGROUND: Adequate pain management after major surgery is important to improve patients' quality of life and to support the healing process. Since the cost for pain management is included in the DRG system for hospital reimbursement, hospitals should aim to provide adequate postoperative pain management at the lowest possible cost. In this study we compare two multimodal pain management schemes for postoperative pain management in a cost-minimisation analysis. METHODS: In a decision analytic model two treatment regimes for postoperative pain management are compared in a cost-minimisation analysis: diclofenac + morphine vs paracetamol vs morphine. The study is performed from the perspective of a public hospital. Due to the short time horizon costs are not discounted. RESULTS: Assuming comparable effectiveness for adequate postoperative pain management, the expected value in the decision tree model for the combination diclofenac + morphine is 13.37 EUR and for the combination paracetamol + morphine 32.23 EUR, respectively. The results are robust under various one- and two-way sensitivity analyses. CONCLUSION: With no contraindications given the combination diclofenac + morphine is more cost-effective for postoperative pain management after major surgery compared to paracetamol + morphine.


Assuntos
Dor Pós-Operatória/terapia , Anti-Inflamatórios não Esteroides/economia , Anti-Inflamatórios não Esteroides/uso terapêutico , Análise Custo-Benefício , Árvores de Decisões , Grupos Diagnósticos Relacionados/economia , Diclofenaco/economia , Diclofenaco/uso terapêutico , Quimioterapia Combinada , Economia Hospitalar , Alemanha , Humanos , Morfina/economia , Morfina/uso terapêutico , Entorpecentes/economia , Entorpecentes/uso terapêutico , Dor Pós-Operatória/economia , Mecanismo de Reembolso
14.
Chem Senses ; 33(7): 655-63, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18603651

RESUMO

Male mice mark the territory with urine scent marks that are frequently renewed to maintain the territory ownership. We measured the response of male mice to small spots of urine deposed either 0, 5, 11, 22, 45, 90 min, or 24 h before testing and show that mice loose interest in sniffing scent marks as they become older and older. We asked what scent features tell a mouse how recent a scent mark is, and therefore, we studied the molecule-to-behavior relationship by correlating 6 behavioral variables--the number of sniffing acts, the latency to the first sniff, the number of urine marks, the latency to the first mark, the area of the marks, and the number of fecal pellets-to 2,4-dehydro-exo-brevicomin, linalool, 2-sec-butyl-4,5-dihydrothiazole, 2,4-dimethylphenol, 4-ethylphenol, and 6,10-dimethyl-5,9-undecadien-2-one released from urine spots over the time, identified, and quantified by gas chromatography and mass spectrometry. Canonical correlation between the molecular and the behavioral principal components was strong (R(1) = 0.96, P = 0.026). The principal component based on 2,4-dehydro-exo-brevicomin, linalool, and 2-sec-butyl-4,5-dihydrothiazole correlated negatively with countermarking and positively with the sniffing behavior, suggesting a semantic feature of fresh male mouse urine.


Assuntos
Comportamento Animal/fisiologia , Olfato/fisiologia , Urina/química , Monoterpenos Acíclicos , Comunicação Animal , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/urina , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Camundongos , Monoterpenos/urina , Territorialidade , Tiazóis/urina , Fatores de Tempo , Urinálise/métodos
15.
Diabet Med ; 23(3): 299-305, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16492214

RESUMO

OBJECTIVE: This population-based study assesses the prevalence and cost of illness as a result of diabetes mellitus in Germany by retrospectively analysing routine health insurance data. Prevalence and costs were analysed from statutory health insurance (GKV) and societal perspectives. RESEARCH DESIGN AND METHODS: The analysis comprises data of all insured persons of six large sickness funds. The insured with diabetes were identified via ICD-9 diagnosis and Anatomical Therapeutic Chemical Classification System (ATC) code for regular medication prescriptions. Costs for inpatient stay, medication and sickness benefits were taken from claims data. Costs for rehabilitation, premature death and early retirement were calculated using the human capital approach and data from national statistics. RESULTS: Overall diabetes prevalence in this age and sex standardized census of six large sickness funds was 6.45%. The cost of illness for sickness funds including hospital cost, medication and sickness benefits, and excluding ambulatory doctor care, were Euro 3.69bn . The total cost of diabetes from a societal perspective was calculated at Euro 5.71bn for the year 1999. CONCLUSION: In accordance with the results of recent studies using routinely collected health insurance data, our study suggests that the prevalence of diabetes mellitus has increased steadily in the past years. The prevalence in our population of 14.7 million insured was 6.45%. Total costs of diabetes mellitus amounted to Euro 5.71bn.


Assuntos
Diabetes Mellitus/epidemiologia , Custos de Cuidados de Saúde , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Diabetes Mellitus/economia , Diabetes Mellitus/reabilitação , Feminino , Alemanha/epidemiologia , Hospitalização/economia , Humanos , Hipoglicemiantes/economia , Hipoglicemiantes/uso terapêutico , Lactente , Seguro Saúde/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Vigilância da População/métodos , Prevalência , Estudos Retrospectivos , Distribuição por Sexo
16.
Eur Respir J ; 25(1): 47-53, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15640322

RESUMO

The purpose of this study was to estimate the prevalence and cost of illness of asthma in Germany by retrospectively analysing routine health insurance data. This analysis investigated claims data from all insured persons of six large sickness funds. Insurants with asthma were identified via the International Classification of Diseases (ninth revision) diagnosis and the Anatomical Therapeutic Chemical Classification System Code for regular medication prescriptions. Costs for hospital care, medication and sick benefit were taken from claims data. Costs for rehabilitation, premature death and early retirement were estimated using the human capital approach and data from national statistics. Prevalence of asthma in the German statutory health insurance was 6.34%. Total costs for asthma, including direct and indirect costs, were calculated at euro 2.74 billion during 1999. The prevalence of asthma in the German statutory health insurance has previously been estimated to be 4-6%. The results of this large study show the prevalence of asthma in the German social insurance system to be approximately 6%. The study also indicates that there is room for substantial savings in the German social insurance system, with indirect costs amounting to 74.8% of total costs and payment of sick benefits through the sickness funds amounting to 58.3% of indirect costs. These costs may be reduced with better asthma control in patients.


Assuntos
Asma/economia , Asma/epidemiologia , Efeitos Psicossociais da Doença , Custos de Cuidados de Saúde , Adolescente , Adulto , Distribuição por Idade , Idoso , Asma/diagnóstico , Asma/terapia , Estudos de Coortes , Análise Custo-Benefício , Feminino , Alemanha/epidemiologia , Custos Hospitalares , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Sistema de Registros , Testes de Função Respiratória , Índice de Gravidade de Doença , Distribuição por Sexo
17.
Sci Total Environ ; 150(1-3): 249-51, 1994 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-7939604

RESUMO

An occupational health and industrial hygiene survey was carried out in Widia tool grinding industries in the area covered by Local Health Unit No. 60--Vimercate (Northern Italy). The principal objectives of the study were to assess occupational cobalt exposure, identify the measures required to improve the 'risk' situations, and implement specific health protocols. The results identified a variable level of occupational hazard in the tool grinding sector. An important factor in the containment of occupational exposure was, along with correct practical procedures, the existence of adequate primary prevention measures (aspiration systems over the machines). In the plants where good industrial hygiene conditions prevailed, environmental cobalt concentrations were below the TLV, whereas the levels recorded in plants with inadequate equipment were as much as 10 times the TLV. Similarly, urinary cobalt for the workers in these same plants was as much as 13 times higher than the reference population value. However, this was recorded in plants with good industrial hygiene conditions. After technical improvements, the results of biological monitoring showed an overall reduction in exposure indicator values.


Assuntos
Poluentes Ocupacionais do Ar/análise , Cobalto/análise , Metalurgia , Exposição Ocupacional/prevenção & controle , Poluentes Ocupacionais do Ar/urina , Cobalto/urina , Humanos
18.
Peptides ; 7(6): 1011-4, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3550723

RESUMO

Long-term (7 and 14 days) hypophysectomy resulted in a striking decrease in growth hormone releasing hormone-like immunoreactivity (GHRH-LI) in the median eminence (ME) of adult male rats, evaluated by both radioimmunoassay and immunohistochemistry. Treatment with human GH (125 micrograms/rat, twice daily IP for 14 days) prevented, though partially, depletion of GHRH-LI from the ME, as assessed by both methods. These results demonstrate that circulating GH levels regulate the function of GHRH-producing structures, via a feedback mechanism.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Hormônio do Crescimento/farmacologia , Hipofisectomia , Hipotálamo/fisiologia , Animais , Hipotálamo/efeitos dos fármacos , Soros Imunes , Masculino , Radioimunoensaio , Ratos , Ratos Endogâmicos
19.
J Endocrinol ; 111(2): 271-8, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2878963

RESUMO

Recently, data have been presented showing that muscarinic cholinergic agonists or antagonists can modulate, in opposite ways, GH-releasing hormone GHRH)-induced GH release in man. The aim of the present study was, first, to confirm these findings in the rat and, secondly, if confirmed, to investigate the mechanism(s) subserving the effect of cholinergic drugs. In adult male rats bearing chronic indwelling atrial cannulae, pretreatment with the cholinergic antagonists pirenzepine (0.5 mg/kg, i.v.) or atropine (0.5 mg/kg, i.v.) significantly reduced the rise in plasma GH induced by GHRH (2 micrograms/kg, i.v.), while pretreatment with the cholinergic agonist pilocarpine (3 mg/kg, i.v.) potentiated it. In rats with hypothalamic somatostatin (SRIF) depletion, i.e. rats with anterolateral deafferentation of the mediobasal hypothalamus or rats treated with cysteamine, the modulatory action of cholinergic drugs on the neuroendocrine effect of GHRH was completely lacking. In these two experimental models, an antiserum raised against SRIF failed to elicit a rise in plasma GH and measurement of hypothalamic SRIF content revealed a clear-cut reduction of the neuropeptide. Atropine (1 mumol/l) and pilocarpine (1 mumol/l), added to pituitary cells in vitro, failed to alter GHRH-induced GH release. The present results indicate that muscarinic cholinergic agonists and antagonists modulate GHRH-induced GH release in the rat and suggest that the effect of cholinergic modulation takes place through SRIF.


Assuntos
Hormônio Liberador de Hormônio do Crescimento/farmacologia , Hormônio do Crescimento/metabolismo , Parassimpatolíticos/farmacologia , Parassimpatomiméticos/farmacologia , Somatostatina/fisiologia , Vias Aferentes/fisiologia , Animais , Atropina/farmacologia , Cisteamina/farmacologia , Hormônio do Crescimento/sangue , Hipotálamo/efeitos dos fármacos , Hipotálamo Médio/análise , Hipotálamo Médio/fisiologia , Técnicas In Vitro , Masculino , Pilocarpina/farmacologia , Pirenzepina/farmacologia , Ratos , Ratos Endogâmicos , Somatostatina/análise
20.
Neuroendocrinology ; 44(1): 59-64, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3097563

RESUMO

Using immunohistochemical techniques, we have studied the ontogenetic development of growth hormone-releasing factor (GRF) immunoreactive structures in the rat hypothalamus. Frozen sections of rat hypothalami were stained by the avidin-biotin complex (ABC) method using a specific antiserum against rat GRF. Immunoreactive GRF nerve terminals but not perikarya were first detected in rat fetuses on the 20th day of gestation in the external layer of the median eminence (ME). An increased number of immunoreactive nerve terminals in the ME were observed at 1 and 2 days of age. In addition, perikarya containing immunoreactive GRF-like material were observed in the arcuate nucleus (ARC). Rats at 5 days of age showed a further increase in GRF immunoreactive terminals, which now were also present in the internal layer of the ME. In 10- and 20-day-old rats immunoreactive nerve terminals were only moderately increased in the ME. GRF immunoreactive perikarya were observed in the ARC and also in proximity to the ventromedial nucleus. Moreover, GRF containing fibers were seen projecting from the ARC to the ME. Colchicine treatment of postnatal rats reduced immunostaining of the nerve animals in the ME, but did not affect that of the perikarya. These results are consistent with the view that the neural control of growth hormone secretion develops in the rat during late gestation and continues to mature during the early postnatal period.


Assuntos
Hormônio Liberador de Hormônio do Crescimento/metabolismo , Hipotálamo/metabolismo , Animais , Núcleo Arqueado do Hipotálamo/metabolismo , Feminino , Hipotálamo/embriologia , Hipotálamo/crescimento & desenvolvimento , Técnicas Imunoenzimáticas , Masculino , Eminência Mediana/metabolismo , Ratos , Ratos Endogâmicos , Núcleo Hipotalâmico Ventromedial/metabolismo
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