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1.
Encephale ; 48(2): 155-162, 2022 Apr.
Artigo em Francês | MEDLINE | ID: mdl-34024499

RESUMO

BACKGROUND: The prevention of Physical Violent Behavior (VB) toward others during psychiatric hospitalization is a major concern of clinicians. These VBs can have a deleterious impact on the victims, inpatients or caregivers, as well as on the therapeutic milieu. Such violence can also have negative consequences for the assailant patients, such as repeatedly being hospitalized under restraint, stigmatization, and difficulties reintegrating into the community. OBJECTIVES: This study explored individual (age, gender, marital status, living status, diagnostic) and institutional (type of admission, length of stay, number of previous hospitalizations) risk factors, and how their interactions could increase the risk of VB during psychiatric hospitalizations. METHOD: The study was carried out over a period of four years in the psychiatry department of the Lausanne University Hospital, on the 15 wards (219 beds) specialized in acute psychiatric care for adults. All the patients admitted to one of these wards during this period (n=4518), aged between 18 and 65 years, were included in the study. The sample was divided in two groups: non-violent patients (NVPs) and violent patients (VPs). VBs, defined as physical aggressions against another person, were assessed by the Staff Observation Aggression Scale - Revised (SOAS - R). Only physical assaults, associated or not with other types of violence, involving hospitalized patients were analyzed. Personal and institutional factors were extracted from the hospital database. Chi2 independence tests were used to assess differences between groups. Logistic regression models were used to identify the links between each factor and the VB. Classification and regression trees were used to study the hierarchical effect of factors, and combinations of factors, on VBs. RESULTS: During the study period, 414 VBs were reported involving 199 patients (4.40 % of all patients). VPs were significantly younger, male, more likely to be unmarried and living in sheltered housing before hospitalization. In this group, the proportion of patients with diagnoses of schizophrenia, and/or schizophrenia with comorbid substance abuse and cognitive impairment, were higher compared to NVPs. VPs were more frequently admitted involuntarily, had a longer average length of stay and a greater number of previous hospitalizations. The logistic regression model performed on individual factors have shown a significant link between age (OR=0.99; CI: 0.97-1.00; P-value=0.024), living in sheltered housing before admission (OR=2.46; CI: 1.61-3.75; P-value<0.000), schizophrenic disorders (OR=2.18; CI: 1.35-3.57; P-value=0.001), schizophrenic disorders with substance abuse comorbidity (OR=2.00; CI: 1.16-3.37; P-value=0.016), cognitive impairment (OR=3.41; CI: 1,21-8.25; P-value=0.010), and VBs. The logistic regression model on institutional factors have shown a significant link between involuntary hospitalization (OR=4.38; CI: 3.20-6.08; P-value<0.000), length of previous stay (OR=1.01; CI: 1.00-1.01; P-value<0.000), number of previous hospitalizations (OR=1.06; CI: 1.00-1.12; P-value=0.031), and VBs. The logistic regression model on individual and institutional factors have shown a significant link between age (OR=0.99; CI: 0.97-1.00; P-value=0.008), living in sheltered housing before admission (OR=2.46: CI: 1.61-3.75; P-value=0.034), cognitive impairment (OR=3.41; CI: 1.21-8.25; P-value=0.074), involuntary hospitalization (OR=3.46; CI: 2.48-4.87; P-value<0.000), length of previous stay (OR=1.01; CI: 1.00-1.01; P-value<0.000), and VBs. The classification and regression trees have shown that the relationship between long length of stay and repeated hospitalizations mainly potentiate the risk of violence. CONCLUSION: The results of this study have shown the existence of a small group of vulnerable patients who accumulate constrained hospital stays during which violence occurs. Exploring the clinical profiles and institutional pathways of patients could help to better identify these patients and promote a more appropriate mode of support, such as intensive clinical case management. This model could facilitate the development of a clinical network and the links between the structures and partners caring for a patient. This would create a continuous support, avoiding or limiting the lack of continuity of care and care disruption.


Assuntos
Transtornos Mentais , Esquizofrenia , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Adulto , Idoso , Agressão/psicologia , Hospitalização , Humanos , Masculino , Transtornos Mentais/complicações , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Pessoa de Meia-Idade , Fatores de Risco , Esquizofrenia/terapia , Violência/psicologia , Adulto Jovem
2.
Encephale ; 45(3): 214-220, 2019 Jun.
Artigo em Francês | MEDLINE | ID: mdl-30446287

RESUMO

OBJECTIVE: This study aims to determine whether it is possible to identify clinical profiles at risk of violent behaviors (VB) in the early phase of psychotic disorders, on the basis of the main dynamic psychopathological risk factors and describe characteristics of the groups with highest levels of violent behaviors. METHOD: A total of 265 patients, aged 18 to 35, treated at the Treatment and early Intervention in Psychosis Program (TIPP-Lausanne), a specialized early psychosis program, were included in this study. We conducted a latent-class analysis and a discriminative analysis on the basis of the main dynamic VB risk factors: substance use disorder, impulsivity, positive symptoms, insight, aggression, hostility, anger, emotional instability and adherence to treatment. These factors were evaluated by specialized scales and on the basis of the Positive and Negative Syndrome Scale (PANSS). VB were restricted to physical aggression against people, defined as "serious violence". They were assessed on the basis of a questionnaire listing violent offenses (Swiss Criminal Code) and VB such as assault and battery, information through the forensic psychiatric services and on the basis of the Staff Observation Aggression Scale (SOAS-R scale) during inpatient treatment phase. RESULTS: Four heterogeneous subgroups were identified with respect to the studied clinical characteristics, including two groups with high rates of VB. The first group, comprising 46% of patients with VB, is distinguished by the prevalence of a range of dimensions related to hostility, impulsivity and emotional instability, associated with high levels of substance abuse and positive symptoms. These clinical dimensions are very significant at the statistical level, since they explain 70% of the construction of subgroups (discriminant analysis). The second group with 37% of patients with VB, is characterized by a lack of insight, lack of adherence to treatment and substance use. These two clinical profiles could increase the impairment of cognitive, functional and relational abilities and contribute to the development of VB in this early phase of psychosis. The third subgroup, with a violent behaviors rate of 28.6%, is distinguished by its high proportion of diagnoses of substance abuse (100%) and women (54%). A last subgroup of patients, the largest quantitatively, has a low proportion of VB (15%) and the lowest levels on the studied factors, suggesting that the majority of patients with this profile commit few VB. CONCLUSION: Our results show that it is possible to identify groups at risk of violent behaviors during the early phase of psychosis on the basis of clinical characteristics that may evolve and therefore be the focus of preventive care. These results highlight the need to target substance use, impulsivity and lack of insight at follow-up in order to prevent VB.


Assuntos
Transtornos Psicóticos/psicologia , Violência/psicologia , Adolescente , Adulto , Idade de Início , Comportamento , Estudos de Coortes , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Prevalência , Escalas de Graduação Psiquiátrica , Medição de Risco , Fatores de Risco , Adulto Jovem
3.
Encephale ; 41(5): 385-93, 2015 Oct.
Artigo em Francês | MEDLINE | ID: mdl-25439859

RESUMO

AIM: In the past few years, spectacular progress in neuroscience has led to the emergence of a new interdisciplinary field, the so-called "neurolaw" whose goal is to explore the effects of neuroscientific discoveries on legal proceedings and legal rules and standards. In the United States, a number of neuroscientific researches are designed specifically to explore legally relevant topics and a case-law has already been developed. In Europe, neuroscientific evidence is increasingly being used in criminal courtrooms, as part of psychiatric testimony, nourishing the debate about the legal implications of brain research in psychiatric-legal settings. Though largely debated, up to now the use of neuroscience in legal contexts had not specifically been regulated by any legislation. In 2011, with the new bioethics law, France has become the first country to admit by law the use of brain imaging in judicial expertise. According to the new law, brain imaging techniques can be used only for medical purposes, or scientific research, or in the context of judicial expertise. This study aims to give an overview of the current state of the neurolaw in the US and Europe, and to investigate the ethical issues raised by this new law and its potential impact on the rights and civil liberties of the offenders. METHOD: An overview of the emergence and development of "neurolaw" in the United States and Europe is given. Then, the new French law is examined in the light of the relevant debates in the French parliament. Consequently, we outline the current tendencies in Neurolaw literature to focus on assessments of responsibility, rather than dangerousness. This tendency is analysed notably in relation to the legal context relevant to criminal policies in France, where recent changes in the legislation and practice of forensic psychiatry show that dangerousness assessments have become paramount in the process of judicial decision. Finally, the potential interpretations of neuroscientific data introduced into psychiatric testimonies by judges are explored. RESULTS: The examination of parliamentary debates showed that the new French law allowing neuroimaging techniques in judicial expertise was introduced in the aim to provide a legal framework that would protect the subject against potential misuses of neuroscience. The underlying fear above all, was that this technology be used as a lie detector, or as a means to predict the subject's behaviour. However, the possibility of such misuse remains open. Contrary to the legislator's wish, the defendant is not fully guaranteed against uses of neuroimaging techniques in criminal courts that would go against their interests and rights. In fact, the examination of the recently adopted legislation in France shows that assessments of dangerousness and of risk of recidivism have become central elements of the criminal policy, which makes it possible, if not likely that neuroimaging techniques be used for the evaluation of the dangerousness of the defendant. This could entail risks for the latter, as judges could perceive neuroscientific data as hard evidence, more scientific and reliable than the soft data of traditional psychiatry. If such neuroscientific data are interpreted as signs of potential dangerousness of a subject rather than as signs of criminal responsibility, defendants may become subjected to longer penalties or measures aiming to ensure public safety in the detriment of their freedom. CONCLUSION: In the current context of accentuated societal need for security, the judge and the expert-psychiatrist are increasingly asked to evaluate the dangerousness of a subject, regardless of their responsibility. Influenced by this policy model, the judge might tend to use neuroscientific data introduced by an expert as signs of dangerousness. Such uses, especially when they subjugate an individual's interest to those of society, might entail serious threats to an individual's freedom and civil liberties.


Assuntos
Legislação Médica/ética , Neurociências/ética , Neurociências/legislação & jurisprudência , Comportamento Perigoso , Europa (Continente) , Prova Pericial , Psiquiatria Legal , França , Humanos , Legislação Médica/tendências , Transtornos Mentais/diagnóstico , Estados Unidos
4.
Rev Med Suisse ; 11(486): 1710, 1712-4, 2015 Sep 16.
Artigo em Francês | MEDLINE | ID: mdl-26591082

RESUMO

Here we present results of studies conducted by the Research Unit of Legal Psychiatry and Psychology of Lausanne about risk assessment and protective factors in the evaluation of violence recidivism. It aims to help experts in considering the relevance and use of tools at their disposal. Particular attention is given to the significance of protective factors and impulsive dimensions, as to the inter-raters process that leads to the final deliberations.


Assuntos
Psiquiatria Legal/métodos , Transtornos Mentais , Prova Pericial , Indicadores Básicos de Saúde , Humanos , Transtornos Mentais/diagnóstico , Transtornos Mentais/psicologia , Testes Neuropsicológicos/normas , Valor Preditivo dos Testes , Prática Profissional , Recidiva , Medição de Risco/métodos , Suíça
5.
Osteoporos Int ; 24(1): 339-47, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23229465

RESUMO

UNLABELLED: Once-yearly administration of intravenous zoledronic acid for 3 years in humans affects the kinetics of matrix filling in by mineral, independent of bone turnover. INTRODUCTION: Yearly 5-mg infusions of zoledronic acid (ZOL) for 3 years have shown pronounced antifracture efficacy. The purpose of the present study was to test whether ZOL affects the kinetics of forming bone material properties maturation. METHODS: Iliac crest biopsies from the HORIZON-PFT clinical trial were analyzed by Raman microspectroscopy in actively bone-forming surfaces as a function of tissue age in trabecular and osteonal bone, to determine ZOL's effect on bone material quality indices maturation kinetics. RESULTS: Mineral/matrix ratio increased in both groups as a function of tissue age, at both osteonal- and trabecular-forming surfaces; ZOL exhibiting the greatest increase in the trabecular surfaces only. The proteoglycan content showed a dependency on tissue age in both trabecular and osteonal surfaces, with ZOL exhibiting lower values in the tissue age 8-22 days in the trabecular surfaces. Mineral crystallinity (crystallite length and thickness) showed a dependence on tissue age, with ZOL exhibiting lower crystallite length compared with placebo only in the 8- to 22-day-old tissue at trabecular surfaces, while crystal thickness was lower in the 1- to 5-day-old tissue at both osteonal and trabecular surfaces. CONCLUSIONS: The results of the present study suggest that once-yearly administration of intravenous ZOL for 3 years in humans does not exert any adverse effects on the evolution of bone material properties at actively forming osteonal and trabecular surfaces, while it may have a beneficial effect on the progression of the mineral-to-matrix ratio and mineral maturity bone quality indices.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Matriz Óssea/efeitos dos fármacos , Difosfonatos/farmacologia , Imidazóis/farmacologia , Osteoporose Pós-Menopausa/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Biópsia , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/administração & dosagem , Conservadores da Densidade Óssea/uso terapêutico , Matriz Óssea/patologia , Matriz Óssea/fisiopatologia , Difosfonatos/administração & dosagem , Difosfonatos/uso terapêutico , Esquema de Medicação , Feminino , Humanos , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Infusões Intravenosas , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Proteoglicanas/metabolismo , Análise Espectral Raman/métodos , Ácido Zoledrônico
6.
Rev Med Suisse ; 8(354): 1775-6, 1778-80, 2012 Sep 19.
Artigo em Francês | MEDLINE | ID: mdl-23097915

RESUMO

The legislatives evolutions imply an important recourse to the psychiatric expertise in order to evaluate the potential dangerousness of a subject. However, in spite of the development of techniques and tools for this evaluation, the dangerousness assessment of a subject is in practice extremely complex and discussed in the scientific literature. The evolution of the concept of dangerousness to the risk assessment involved a technicisation of this evaluation which should not make forget the limits of these tools and the need for restoring the subject, the meaning and the clinic in this evaluation.


Assuntos
Criminosos , Medição de Risco , Violência/psicologia , Humanos , Recidiva
7.
Vaccine ; 40(25): 3455-3460, 2022 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-35534311

RESUMO

OBJECTIVE: To determine pertussis and influenza vaccination coverage during pregnancy among women delivering in all the maternities of Geneva (Switzerland), during the COVID-19 pandemic. METHODS: All women delivering in all the maternity centres of the canton of Geneva from 1st November 2020 to 30th November 2020 (beginning of the flu vaccination season) and from 8th March 2021 to 7th April 2021 (end of the flu vaccination season) had their records checked upon admission to the labour ward regarding pertussis and influenza vaccination during pregnancy. Reasons for non-vaccination were recorded. Univariate and multivariate analyses were done to identify predictors of vaccine uptake. RESULTS: 951 women delivered in Geneva during the two study periods, of which 950 were included in the study. 86.2% were vaccinated against pertussis, with no significant difference between the study periods (87.5% vs 85% at the beginning and end of the flu vaccination season respectively). 49.8% were vaccinated against influenza, with no significant difference between the study periods (48.8% vs 50.7% beginning and end of the flu vaccination season respectively). The influenza vaccine was 5 times more likely not to be proposed (8.9% vs. 1.7%) and 3 times more likely to be refused (26.6% vs. 8%) than the pertussis vaccine. Main reason for refusal was a lack of maternal desire for both vaccines, but not vaccine fear. Maternal parity ≥ 1 was significantly associated with pertussis vaccine uptake at univariate analysis. Women were significantly more likely to accept the influenza vaccine if they had a university degree or if they did not deliver in a midwife-only run delivery unit in both univariate and multivariate analysis. CONCLUSIONS: In Geneva, most gynaecologists offer pertussis immunization during antenatal care and uptake is high, but more efforts must be done to increase influenza vaccination coverage. Education level impacts maternal flu vaccination uptake, but other social disparities did not.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Complicações Infecciosas na Gravidez , Coqueluche , COVID-19/epidemiologia , COVID-19/prevenção & controle , Feminino , Humanos , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Vacina contra Coqueluche , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Estudos Prospectivos , Vacinação , Coqueluche/epidemiologia , Coqueluche/prevenção & controle
8.
Ann Rheum Dis ; 69(1): 284-90, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19196726

RESUMO

OBJECTIVES: Chronic inflammation is a major risk factor for systemic bone loss leading to osteoporotic fracture and substantial morbidity and mortality. Inflammatory cytokines, particularly tumour necrosis factor (TNF) and interleukin-1 (IL1), are thought to play a key role in the pathogenesis of inflammation-induced bone loss, but their exact roles are yet to be determined. METHODS: To determine whether TNF directly triggers bone loss or requires IL1, human TNFalpha mice (hTNFtg) were crossed with mice lacking IL1alpha and IL1beta (IL1(-/-)hTNFtg). Systemic bone architecture was evaluated using CT scanning, static and dynamic bone histomorphometry and serum markers of bone metabolism. RESULTS: hTNFtg mice developed severe bone loss accompanied by a severe distortion of bone microarchitecture. Bone trabeculae were thinner and decreased in numbers, resulting in increased trabecular separation. Histomorphometric analyses revealed strongly increased bone resorption in hTNFtg mice compared with wild-type mice. In contrast, IL1(-/-)hTNFtg mice were fully protected from systemic bone loss despite still developing inflammation in their joints. Lack of IL1 completely reversed increased osteoclast formation and bone resorption in hTNFtg mice and the increased levels of RANKL in these mice. Structural parameters and osteoclast and osteoblast numbers were indistinguishable from wild-type mice. CONCLUSIONS: These data indicate that IL1 is essential for TNF-mediated bone loss. Despite TNF-mediated inflammatory arthritis, systemic bone is fully protected by the absence of IL1, which suggests that IL1 is an essential mediator of inflammatory osteopenia.


Assuntos
Artrite Experimental/complicações , Artrite Reumatoide/complicações , Doenças Ósseas Metabólicas/etiologia , Interleucina-1/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Biomarcadores/sangue , Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/metabolismo , Doenças Ósseas Metabólicas/patologia , Doenças Ósseas Metabólicas/fisiopatologia , Reabsorção Óssea/fisiopatologia , Tomografia com Microscopia Eletrônica , Feminino , Interleucina-1/deficiência , Camundongos , Camundongos Transgênicos , Osteoblastos/patologia , Osteoclastos/patologia , Tíbia/ultraestrutura
10.
J Phys Condens Matter ; 21(24): 245107, 2009 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21693940

RESUMO

We investigate the structure of liquid monotectic alloy Bi(30)Ga(70) above and below the critical point. The three-dimensional structure at 265 °C is modelled by means of the reverse Monte Carlo simulation technique using neutron and x-ray diffraction experimental data. It is shown that atomic segregation on the short-range scale exists in the liquid Bi(30)Ga(70) slightly above the critical temperature (T(C) = 262 °C). We present also the structure factors of Bi(30)Ga(70) liquid alloy under the critical point at 240 and 230 °C obtained with neutron diffraction to highlight the temperature effect in the atomic structure.

12.
Eur Psychiatry ; 49: 30-36, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29353178

RESUMO

BACKGROUND: Violent behaviour (VB) occurs in first episode of schizophrenia and can have devastating impact both on victims and patients themselves. A better knowledge of the underlying mechanisms of VB may pave the way to preventive treatments. OBJECTIVES: 1) To explore the nature of the link between impulsivity and VB in early psychosis (EP) patients; 2) To explore the interactions between impulsivity and substance abuse, insight, and positive symptoms, the main dynamic risk factors of VB described to date. DESIGN AND METHODS: Post hoc analysis of data acquired in the frame of a 36-months EP cohort study. A total of 265 EP patients, aged 18 to 35, treated at TIPP (Treatment and early Intervention in Psychosis Program), at the Department of Psychiatry in Lausanne, Switzerland, were included in the study. Logistic regression analyzes were performed as well as mediation analysis and interaction analysis RESULTS: Our data suggest that impulsivity is a predictor of VB when analyzed independently and as part of a multi-factorial model. Impulsivity continues to differentiate violent patients from non-violent ones at the end of the program. In addition, the relationship between impulsivity and VB is not mediated by substance abuse. Finally, the effect of impulsivity on the probability of VB is potentiated by the interaction of different levels of insight and positive symptoms. CONCLUSIONS: Early intervention strategies in psychotic disorders should include evaluation of impulsivity considering it is linked to increased risk of VB and may respond to treatment.


Assuntos
Comportamento Impulsivo , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/psicologia , Esquizofrenia/epidemiologia , Violência/psicologia , Violência/estatística & dados numéricos , Adulto , Estudos de Coortes , Comorbidade , Feminino , Seguimentos , Humanos , Modelos Logísticos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Transtornos Psicóticos/terapia , Fatores de Risco , Esquizofrenia/terapia , Inquéritos e Questionários , Suíça/epidemiologia , Violência/prevenção & controle , Adulto Jovem
14.
Cell Signal ; 5(2): 145-53, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8499224

RESUMO

Platelets from patients with insulin-dependent diabetes with proliferative retinopathy showed the same reactivity to ADP as those from control subjects. Responsiveness of platelets to the aggregation inhibitor adenosine and to the analogue N-ethylcarboxamidoadenosine was decreased in diabetes. In contrast, responsiveness to the anti-aggregatory effects of prostaglandin I2 was not significantly altered in diabetes. Platelets from diabetic patients exhibited decreased formation of cyclic AMP in response to N-ethylcarboxamidoadenosine compared with those from control subjects. In contrast, when adenylyl cyclase was stimulated by prostaglandin I2 or by forskolin, no differences in cyclic AMP formation were observed between control and diabetic platelets. Diabetes was associated with an apparent loss of high-affinity binding of [3H]N-ethylcarboxamidoadenosine to platelet membranes. Possible mechanisms that could contribute to this diabetes-induced change in signalling through the platelet A2 adenosine receptor are discussed.


Assuntos
Adenosina/análogos & derivados , Adenosina/farmacologia , Plaquetas/efeitos dos fármacos , Diabetes Mellitus Tipo 1/metabolismo , Retinopatia Diabética/metabolismo , Receptores Purinérgicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adenosina/metabolismo , Difosfato de Adenosina/antagonistas & inibidores , Difosfato de Adenosina/farmacologia , Adenosina-5'-(N-etilcarboxamida) , Sítios de Ligação , Membrana Celular/metabolismo , Colforsina/farmacologia , Diabetes Mellitus Tipo 1/complicações , Retinopatia Diabética/sangue , Retinopatia Diabética/complicações , Epoprostenol/farmacologia , Feminino , Proteínas de Ligação ao GTP/fisiologia , Humanos , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos
15.
Endocrinology ; 156(2): 419-28, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25396268

RESUMO

PTH is indicated for the treatment of severe osteoporosis. Elderly osteoporotic patients frequently suffer from protein malnutrition, which may contribute to bone loss. It is unknown whether this malnutrition may affect the response to PTH. Therefore, the aim of the present study was to assess whether an isocaloric low-protein (LP) diet may influence the bone anabolic response to intermittent PTH in 6-month-old female rats. Six-month-old female rats were either pair fed an isocaloric LP diet (2.5% casein) or a normal-protein (NP) diet (15% casein) for 2 weeks. The rats continued on their respective diet while being treated with 5- or 40-µg/kg recombinant human PTH amino-terminal fragment 1-34 (PTH-[1-34]) daily, or with vehicle for 4 weeks. At the end of this period, areal bone mineral density, bone mineral content, microstructure, and bone strength in axial compression of proximal tibia or 3-point bending for midshaft tibia tests were measured. Blood was collected for the determination of IGF-I and osteocalcin. After 4 weeks of PTH-(1-34), the dose-dependent increase of proximal tibia bone mineral density, trabecular microstructure variables, and bone strength was attenuated in rats fed a LP diet as compared with rats on a NP intake. At the level of midshaft tibia cortical bone, PTH-(1-34) exerted an anabolic effect only in the NP but not in the LP diet group. Protein malnutrition was associated with lower IGF-I levels. Protein malnutrition attenuates the bone anabolic effects of PTH-(1-34) in rats. These results suggest that a sufficient protein intake should be recommended for osteoporotic patients undergoing PTH therapy.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Hormônio Paratireóideo/farmacologia , Deficiência de Proteína/metabolismo , Animais , Feminino , Fator de Crescimento Insulin-Like I/metabolismo , Osteocalcina/sangue , Osteoporose/complicações , Osteoporose/tratamento farmacológico , Hormônio Paratireóideo/uso terapêutico , Deficiência de Proteína/complicações , Distribuição Aleatória , Ratos Sprague-Dawley
16.
J Bone Miner Res ; 10(11): 1726-34, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8592950

RESUMO

The current study employs the immobilization (IM) rat model to induce osteopenia, parathyroid hormone (PTH) as the anabolic agent to restore bone mass, and 17 beta-estradiol, calcitonin, or risedronate as the maintenance agents to answer the following questions: How much cancellous bone loss occurs when PTH is withdrawn? Which antiresorptive or antiactivation agent maintains bone best? Ideally, what tissue-level histomorphometric conditions maintain added bone? Six-month-old female rats were treated with 200 micrograms PTH/day subcutaneously at 30 days post-IM for 75 days. Then PTH treatment was stopped and switched to a vehicle (no treatment), 10 micrograms calcitonin/kg/day, 10 micrograms 17 beta-estradiol/kg/day, or 5 micrograms risedronate twice weekly for another 15 days (early response) or 60 days (late response). The rats had their right hindlimb throughout the study. The current report deals only with the maintenance phase involving 92 animals. Bone histomorphometry was performed on the secondary spongiosa of the right proximal tibia metaphysis (PTM). Cessation of PTH treatment followed by vehicle administration for 15 days resulted in partial loss of trabecular bone area and thickness from stimulated bone resorption and the fall of all formation indices. By contrast, all three antiresorptive agents maintained the cancellous bone mass during the same period. However, after prolonged withdrawal of PTH for 60 days, we found that 17 beta-estradiol and calcitonin maintained the cancellous bone slightly better than no treatment, while risedronate partially protected it from the mechanostat-induced bone loss. The risedronate treatment retained 71% of the PTH-added bone while calcitonin retained 48%, estrogen 42%, and no treatment 32%. The favorable histomorphometry profile for maintenance was the sustained reduction in bone resorption and turnover and normal age-related bone balance. We concluded that 1) cessation of PTH treatment will result in the loss of two-thirds of the added bone in 60 days; 2) currently, risedronate at the dose level employed as a maintenance agent is far superior to 17 beta-estradiol or calcitonin because of its long retention in bone; however, a longer observation period might result in less difference; and 3) the ideal tissue-level histomorphometry continues depressing bone resorption and turnover and maintains a normal age-related bone balance. Furthermore, we found the "lose, restore plus add, and maintain (LRAM)" concept was successful in maintaining most of the PTH-induced extra bone by risedronate for 60 days. It was far superior to 17 beta-estradiol or calcitonin. Possibly the last two agents would be effective in maintaining a normal amount of bone but not in preserving an excessive amount of bone. Nevertheless, the current study further emphasizes that clinicians should consider using the LRM treatment strategy when they plan to treat osteoporosis with bone anabolic agents.


Assuntos
Doenças Ósseas Metabólicas/tratamento farmacológico , Reabsorção Óssea/tratamento farmacológico , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/farmacologia , Animais , Densidade Óssea/efeitos dos fármacos , Calcitonina/administração & dosagem , Calcitonina/farmacologia , Modelos Animais de Doenças , Estradiol/administração & dosagem , Estradiol/farmacologia , Ácido Etidrônico/administração & dosagem , Ácido Etidrônico/análogos & derivados , Ácido Etidrônico/farmacologia , Feminino , Humanos , Osteoporose Pós-Menopausa/tratamento farmacológico , Hormônio Paratireóideo/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Ácido Risedrônico
17.
Endocrinology ; 134(5): 2126-34, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8156913

RESUMO

The aim of the study was to assess the long term effect of the antiresorptive agents estrogen and salmon calcitonin, the anabolic drug PTH, and combination therapy on vertebral bone mass and bone biomechanical competence in aged osteopenic ovariectomized (OVX) rats. Seventy-nine 1-yr-old retired breeder Wistar rats were randomized into seven groups: 1) sham-operated, 2) OVX, 3) OVX plus estrogen, 4) OVX plus salmon calcitonin, 5) OVX plus human (h) PTH-(1-38), 6) OVX plus hPTH-(1-38) and estrogen, and finally, 7) OVX plus hPTH-(1-38) and calcitonin. Treatment regimens were initiated 8 weeks after ovariectomy and continued for 24 weeks. Whole body bone mass was measured by dual photon absorptiometry at intervals of 4 weeks and at death. Changes in spinal bone mass (BMC), biomechanical competence, and structure were assessed from the lumbar vertebral bodies. The results revealed a protective effect of both estrogen and calcitonin on ovariectomy-induced loss of whole body bone mass, but only estrogen had a significant effect on spinal BMC. hPTH-(1-38) monotherapy increased vertebral bone mass (BMC and ash content), size, and biomechanical parameters 20-80% over OVX levels. A more rapid effect on vertebral bone mass was seen when hPTH-(1-38) was combined with estrogen or salmon calcitonin. The study has shown that in aged OVX osteopenic rats, hPTH-(1-38) therapy increases vertebral bone mass and bone quality and also maintains trabecular connectivity. Both estrogen and calcitonin reduce the ovariectomy-induced bone loss, but cannot restore bone mass to sham-operated levels. On the basis of this study, it is concluded that PTH therapy seems to hold promise in the management of postmenopausal and age-related osteoporosis.


Assuntos
Envelhecimento , Osso e Ossos/fisiologia , Calcitonina/farmacologia , Estradiol/farmacologia , Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/farmacologia , Absorciometria de Fóton , Animais , Fenômenos Biomecânicos , Reabsorção Óssea , Osso e Ossos/efeitos dos fármacos , Feminino , Microscopia Eletrônica de Varredura , Ovariectomia , Ratos , Ratos Wistar , Coluna Vertebral/fisiologia
18.
Clin Pharmacol Ther ; 18(2): 175-9, 1975 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1097153

RESUMO

A respiratory study has been done to compare the respiratory effects of a potent new analgesic, nefopam, to morphine. Morphine was a potent respiratory depressant at therapeutic dosage while nefopam was not.


Assuntos
Nefopam/farmacologia , Oxazocinas/farmacologia , Respiração/efeitos dos fármacos , Ensaios Clínicos como Assunto , Depressão Química , Humanos , Masculino , Morfina/farmacologia , Placebos , Fatores de Tempo
19.
Clin Pharmacol Ther ; 18(2): 170-4, 1975 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-239807

RESUMO

The respiratory effects of a new benzodiazepine, lorazepam, were compared to those of pentobarbital and pentazocine. Pentobarbital, 50 and 150 mg, produced respiratory depression, as did pentazocine, 30 mg intramuscularly. Lorazepam at 1.33 and 4 mg intramuscularly produced none.


Assuntos
Ansiolíticos/farmacologia , Lorazepam/farmacologia , Pentazocina/farmacologia , Pentobarbital/farmacologia , Respiração/efeitos dos fármacos , Dióxido de Carbono/metabolismo , Ensaios Clínicos como Assunto , Depressão Química , Humanos , Masculino
20.
FEBS Lett ; 160(1-2): 61-6, 1983 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-6309568

RESUMO

Phosphorylation of phospholamban by either a cAMP-dependent or a calmodulin-dependent kinase stimulates the Ca2+ transporting activity of cardiac sarcoplasmic reticulum membranes. It has now been found that phospholamban consists of 2 distinct proteins; one is the specific substrate for the cAMP-dependent phosphorylation, and the other for the calmodulin-dependent kinase. In spite of functional diversity, the 2 polypeptides share a number of properties. Among them, the proteolipid character, Mr, resistance to trypsinization, and subunit composition.


Assuntos
Adenosina Trifosfatases/isolamento & purificação , Proteínas de Ligação ao Cálcio/isolamento & purificação , Miocárdio/enzimologia , Proteolipídeos/isolamento & purificação , Retículo Sarcoplasmático/enzimologia , Animais , Calmodulina/farmacologia , Bovinos , AMP Cíclico/farmacologia , Cinética , Fosforilação , Proteínas Quinases/metabolismo , Ratos
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