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1.
Z Gerontol Geriatr ; 36(3): 204-15, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12825138

RESUMO

The differences in training and services in geriatric medicine between European Union member countries raise some questions: what is a geriatrician, what is geriatric medicine, what will be the future development of the specialty and how does it interact with other medical specialties? To find answers to these questions, a questionnaire was sent to a selected group of 122 geriatricians. The response rate was 60%. A description has been given of what is a geriatrician and what is geriatric medicine. Based on data from the literature and the answers of the respondents six future scenarios were designed. The six scenarios are: the 'healthy old people', the 'adapted specialties', the 'general practitioner + additional training', the 'co-ordinator geriatrician', the 'community geriatrician' and the 'hospital geriatrician'. The answers of the respondents gave doubts whether general practitioners are able to provide the full range of services for geriatric patients in the community. A small majority of the respondents opted for a division of the specialty into community geriatric medicine and hospital geriatric medicine. Such a division offers good opportunities to raise the quality of medical services and to reduce age-related treatment limitation. It is expected that some aspects of geriatric medicine will be included in the training of other specialties and some GPs will obtain additional training. The collected data can not be considered as a representation of the ideas of the European Union geriatricians. However, they may contribute to the discussion on the national and European level about the future of the specialty.


Assuntos
Geriatria , Idoso , Medicina Comunitária , Educação de Pós-Graduação em Medicina , União Europeia , Medicina de Família e Comunidade/educação , Medicina de Família e Comunidade/tendências , Previsões , Geriatria/educação , Geriatria/tendências , Humanos , Corpo Clínico Hospitalar , Inquéritos e Questionários
3.
Endocrinology ; 142(11): 4813-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11606448

RESUMO

Changes in body composition occur around the menopausal transition. The major characteristics are a decline in fat-free mass and an increase in body fat as a percentage of body weight. These alterations might be affected by age only or by menopause-related changes in hormone concentration. In this study the effects of tibolone, a tissue-specific compound with favorable effects on bone, vagina, and climacteric symptoms, were determined on body composition using bioelectrical impedance analysis. The focus was especially on fat mass, fat-free mass, and total body water in a group of 85 healthy women (mean +/- SD age, 54.2 +/- 4.7 yr), between 1-15 yr postmenopausal. Participants were randomly assigned to either tibolone (2.5 mg; n = 42) or identically appearing placebo tablets (n = 43) daily for 12 months. All analyses were based on the intent to treat group and last visit. Compared with placebo, tibolone significantly increased fat-free mass by 0.85 kg (P = 0.003) and total body water by 0.78 liter (P = 0.001). No significant difference was observed on the fat mass parameter (P = 0.16). From these results it can be concluded that tibolone may counteract the postmenopausal changes in body composition.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Anabolizantes/farmacologia , Composição Corporal/efeitos dos fármacos , Água Corporal/metabolismo , Norpregnenos/farmacologia , Pós-Menopausa/fisiologia , Magreza , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa/efeitos dos fármacos
4.
Aging (Milano) ; 13(1): 16-21, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11292147

RESUMO

The objective of our cross-sectional study was to investigate the changes associated with age and gender in walking speed, stride length and cadence of healthy women and men over the adult age range, and establish the effects of anthropometric indices such as height and body weight. We examined 118 women and 121 men (age range, 19-90 years). Subjects walked at their preferred speed over a 12-meter walkway crossing two Kistler force plates: cadence was calculated from heel strike times recorded from the Kistler force plates; walking speed was measured using an infrared reflecting system; and stride length was calculated from the walking speed and cadence. Older healthy subjects had lower values for walking speed and stride length than younger subjects. While there is little difference in the percentage reduction between women and men over the adult age range. the absolute values for walking speed are lower in women than men at all ages. In women, the percentage of explained variance for decline in walking speed was 30%, and for decline in stride length 400%. If body weight was also taken into account, the percentage of explained variance for walking speed was 37%, and for stride length 59%. A similar calculation for men yields 34% for decline in walking speed, and 42% for decline in stride length. Cadence was not associated with age, height and body weight. The standard errors for the estimates of walking speed in both women and men, respectively, are reduced by 8% and 3% using the multiple regression technique. The corresponding standard errors for stride length were reduced by, respectively, 19% and 13% if height in either sexes, or height and body weight in women, were taken into account. In conclusion, preferred walking speed and stride length decline with age in healthy people. Lower values found in old healthy subjects partly contributed to the difference in height and body weight between old and young subjects. Cadence was not correlated with age, height and body weight.


Assuntos
Envelhecimento/fisiologia , Estatura , Peso Corporal , Marcha , Caminhada , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Caracteres Sexuais , Fatores de Tempo
5.
J Clin Nurs ; 10(6): 721-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11822843

RESUMO

This review focuses on delirium and early recognition of symptoms by nurses. Delirium is a transient organic mental syndrome characterized by disturbances in consciousness, thinking and memory. The incidence in older hospitalized patients is about 25%. The causes of delirium are multi-factorial; risk factors include high age, cognitive impairment and severity of illness. The consequences of delirium include high morbidity and mortality, lengthened hospital stay and nursing home placement. Delirium develops in a short period and symptoms fluctuate, therefore nurses are in a key position to recognize symptoms. Delirium is often overlooked or misdiagnosed due to lack of knowledge and awareness in nurses and doctors. To improve early recognition of delirium, emphasis should be given to terminology, vision and knowledge regarding health in ageing and delirium as a potential medical emergency, and to instruments for systematic screening of symptoms.


Assuntos
Delírio/diagnóstico , Delírio/enfermagem , Avaliação em Enfermagem/métodos , Distribuição por Idade , Idoso , Delírio/epidemiologia , Delírio/etiologia , Diagnóstico Diferencial , Emergências , Avaliação Geriátrica , Humanos , Incidência , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Avaliação em Enfermagem/normas , Fatores de Risco , Fatores de Tempo , Gestão da Qualidade Total
6.
Age Ageing ; 29(3): 235-42, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10855906

RESUMO

OBJECTIVE: we measured muscle strength and functional mobility in healthy men and women over the adult age range to investigate the changes with age and sex, and to establish the effects of the anthropometric indices height and weight. DESIGN: cross-sectional study. SUBJECTS AND METHODS: we recruited 74 healthy women (mean age 49.0, range 20-90) and 81 healthy men (mean age 51.6, range 20-90). We measured maximum isometric knee extension strength, handgrip strength and explosive leg extensor power. We assessed functional mobility quantitatively with the timed 'get up and go' test and the modified Cooper test. RESULTS: older subjects had lower values for muscle strength and muscle power than young subjects. Times for the timed 'get up and go' test were longer and distances in the modified Cooper test shorter. At about the age of 55, women showed an acceleration in the decline of isometric knee extension strength and handgrip strength (between 20 and 55 years, knee strength decreased by 10.3% and handgrip strength decreased by 8.2%, between 55 and 80 years the decreases were 40.2% and 28% respectively). Men showed a more gradual declines over the adult age range, with decreases in knee and handgrip strength of 24% and 19.6% between 20 and 55 years, and 23% and 17.4% between 55 and 80 years. The age-related decline is partly associated with differences in height and body weight. Women had higher correlations between muscle strength and functional mobility tests than men. CONCLUSIONS: muscle strength and functional mobility decline with age in healthy people; in women we observed an accelerated decrement in muscle strength above the age of 55. Lower values in healthy old subjects are partly associated with differences in height and body weight.


Assuntos
Envelhecimento/fisiologia , Análise e Desempenho de Tarefas , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Estatura , Peso Corporal , Estudos Transversais , Feminino , Nível de Saúde , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia
7.
Aging (Milano) ; 12(6): 455-60, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11211956

RESUMO

Vitamin D deficiency may lead to loss of type II muscle fibres, and thereby to atrophy of proximal muscles with an increased risk of falling and bone fractures. The aim of the study was to determine if six months of vitamin D treatment (0.5 microg alphacalcidol) could positively influence values for muscle strength and functional mobility in vitamin D-deficient older women. Twenty-seven women entered the study which took place at a teaching hospital outpatient department. Ten vitamin D-deficient (serum 25(OH)D3 <20 nmol/L) older (>70 years) women and 13 age-matched female subjects with normal vitamin D levels (serum 25(OH)D3 >30 nmol/L) completed the study. Preand post-treatment data were obtained for isometric knee extensor strength, handgrip strength and functional mobility (walking distance over 2 minutes and the timed i'Up & Go" test). Six months of treatment with alphacalcidol led to significant improvements (compared to the controls) in values of isometric knee extensor strength (left leg: 14.6% +/- 5.7%. p=0.03; right leg: 11.5% +/- 5.0%, p=0.02) (mean +/- SEM). The achievements in the timed "Up & Go" test and 2-minute walking test did not improve in the alphacalcidol group compared to the controls after 6 months. However, within the vitamin D-deficient group, 6 months of alphacalcidol treatment led to a significant increase in the walking distance over 2 minutes (increase from 137.6 +/- 12.6 to 151.3 +/- 11.2 meters, p=0.03). The controls, with normal vitamin D levels, did not exhibit improvements in performance of any of the tests over a period of 6 months. Summarized, alphacalcidol seems to improve muscle strength and walking distance over 2 minutes in vitamin D-deficient older women.


Assuntos
Força da Mão , Hidroxicolecalciferóis/uso terapêutico , Atividade Motora/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Deficiência de Vitamina D/tratamento farmacológico , Deficiência de Vitamina D/fisiopatologia , Idoso , Feminino , Humanos , Contração Isométrica/efeitos dos fármacos , Joelho , Valores de Referência , Fatores de Tempo , Caminhada
8.
Ned Tijdschr Geneeskd ; 143(31): 1600-2, 1999 Jul 31.
Artigo em Holandês | MEDLINE | ID: mdl-10488370

RESUMO

The Dutch College of General Practitioners published well documented guidelines for the management of osteoporosis. It is however incorrect to use the Z-score for the elderly and the T-score for other age groups. The guidelines balance the patient's and the physician's interests and the financial consequences of osteoporosis. They demand certainty about recommending the GP's interventions and accept less certainty where the influence on the GP's activities is limited. The guidelines contain weighed judgements by and for GP's; it is questionable whether they are adequate regarding the interaction with the increasingly well informed patient.


Assuntos
Medicina Interna/normas , Osteoporose , Guias de Prática Clínica como Assunto/normas , Adulto , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Países Baixos , Osteoporose/diagnóstico , Osteoporose/prevenção & controle , Osteoporose/terapia , Relações Médico-Paciente
9.
Ned Tijdschr Geneeskd ; 142(34): 1915-9, 1998 Aug 22.
Artigo em Holandês | MEDLINE | ID: mdl-9856178

RESUMO

Fluoride changes the composition of the hydroxyapatite crystal, reducing the solubility of the bone crystals. Fluoride also stimulates the production of DNA and new osteoblasts, which results in formation of new bone. The therapeutical range of fluoride is narrow. With monofluorophosphate in a dose of 76 mg twice daily positive effect on bone mass is obtained and measurement of serum fluoride concentration is unnecessary. For the treatment of osteoporosis the best result could be obtained with a combined treatment with monofluorophosphate, stimulating osteoblasts and production of new bone, and a bisphosphonate, which simultaneously inhibits osteoclasts and bone resorption. Using this combined treatment only few side effects and no lower extremity pain syndrome were observed. Patients > 65 years of age and younger patients showed similar positive effects on bone mass.


Assuntos
Densidade Óssea/efeitos dos fármacos , Difosfonatos/uso terapêutico , Fluoretos/uso terapêutico , Osteoporose/tratamento farmacológico , Idoso , Quimioterapia Combinada , Feminino , Fluoretos/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos
10.
Pharm World Sci ; 20(5): 214-8, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9820884

RESUMO

The genotoxicity of fluoride in vivo in seven patients with osteoporosis was cytogenetically investigated. The patients were treated with fluoride-containing formulations (disodium monofluorophosphate and sodium fluoride) for a period of 15 months up to 49 months. Fluoride intake ranged from 22.6-33.9 mg F/day and serum fluoride concentrations were between 0.1 mg F/l and 0.2 mg F/l. Peripheral blood lymphocytes of these patients were cultured in vitro and examined for chromosomal aberrations, micronuclei in cytokinesis-blocked binucleated lymphocytes as well as cell cycle progression. When a comparison was made between patients' group and a matched control group, it was found that fluoride at the tested concentrations had no detectable genotoxic potential in human.


Assuntos
Aberrações Cromossômicas , Fluoretos/efeitos adversos , Linfócitos/efeitos dos fármacos , Linfócitos/ultraestrutura , Osteoporose/sangue , Adulto , Idoso , Ciclo Celular/efeitos dos fármacos , Método Duplo-Cego , Feminino , Fluoretos/uso terapêutico , Humanos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Testes para Micronúcleos , Pessoa de Meia-Idade , Osteoporose/tratamento farmacológico , Osteoporose/genética
11.
Osteoporos Int ; 8(2): 174-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9666942

RESUMO

A consensus report on osteoporosis in The Netherlands recommends general practitioners to use an arm span-height difference of at least 3 cm as one of the criteria for suspecting osteoporosis. In this study it was investigated how well this criterion discriminates between patients with established osteoporosis and controls in a group of postmenopausal women. When the Dutch general practitioners criterion of arm span-height difference exceeding 3 cm was applied in a logistic regression analysis to predict the probability of having osteoporosis, a resultant sensitivity of 58% and a specificity of 56% were found. In order to improve the predicted probability of osteoporosis, two more predictors in addition to the arm span-height difference were introduced in the logistic regression model. The first additional predictor related to information whether subject's age was below or above 70 years, and the second whether the arm span was below or above 160 cm. All three predictors appeared to be highly significant. It was shown that the predicted probability of osteoporosis by this model could be considerably improved when the age category and the arm span category were also taken into account, leading to a sensitivity of 81% while the specificity amounts to 64%. This seems quite satisfactory for such a simple method and clearly improves on the original single criterion of arm span-height difference.


Assuntos
Braço/anatomia & histologia , Osteoporose Pós-Menopausa/diagnóstico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antropometria , Estatura , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade
12.
J Gerontol A Biol Sci Med Sci ; 53(3): M242-7, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9597058

RESUMO

BACKGROUND: Mobility measurements were performed on healthy adult subjects to investigate changes over the adult age range and to obtain reference values. METHODS: Ninety-five males (19-90 years, mean 58.2) and 122 females (19-90 years, mean 51.8) were measured using the commercially available Postural-Locomotor-Manual Test (PLM-test). Subjects are required to perform a standard maneuver that is recorded using an optoelectronic technique. RESULTS: Older subjects carried out all phases of the maneuver more slowly than younger subjects. At about the age of 50 years, females showed a more rapid slowing down. Males showed a more gradual decrease over the adult age range. CONCLUSION: The PLM-test provides a fairly simple noninvasive method of assessing motor performance. However, it is important to separate male and female data in the determination of reference values.


Assuntos
Envelhecimento/fisiologia , Locomoção/fisiologia , Movimento/fisiologia , Postura , Desempenho Psicomotor/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Mãos , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Caracteres Sexuais , Fatores de Tempo
13.
Ned Tijdschr Geneeskd ; 141(45): 2145-7, 1997 Nov 08.
Artigo em Holandês | MEDLINE | ID: mdl-9550792

RESUMO

In three patients, two men aged 84 and 80, and a women aged 88, physicians had advised against further diagnostic examination or treatment, mainly because of the advanced age. One of the patients was not satisfied with his deterioration and asked for further examination, the other two were brought to the hospital by relatives in order to be further examined. In all three cases, additional investigation revealed treatable disorders (Crohn's disease, depressive disorder and complications of Parkinson's disease). It is argued that very old age as such is not a sufficient reason to refrain from further diagnostic investigation or treatment. Sufficient reasons are (a) certainty with respect to the diagnosis, (b) knowledge of technical aspects of diagnosis and treatment, notably regarding potential yield and stress for the patient, and (c) approval by the patient, his representative or family members.


Assuntos
Doença de Crohn/diagnóstico , Demência/diagnóstico , Depressão/diagnóstico , Doença de Parkinson/diagnóstico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Doença de Crohn/tratamento farmacológico , Depressão/tratamento farmacológico , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Doença de Parkinson/tratamento farmacológico , Encaminhamento e Consulta
16.
Age Ageing ; 25(3): 234-8, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8670560

RESUMO

Resuscitation decisions during the first 6 weeks were analysed for 97 admissions to a psychogeriatric ward of a general teaching hospital. Seventy-seven patients (79%) had a written 'do not resuscitate' (DNR) order on admission and 74 patients (875) had a written DNR order after 6 weeks. Morbidity was assessed with a pre-arrest morbidity (PAM) index and a modified PAM index (MPI). Dementia influenced the presence of a DNR order, both because lack of effectiveness of CPR and lack of quality of life. Age was related to a DNR order. The MPI was associated with the presence of a written DNR order, while the PAM score failed to reach significance. Six weeks after admission DNR orders were predictable by the four variables of dementia, the use of antidepressants, age and PAM, in that order. The association of the use of antidepressants with the presence of a written DNR order was surprising. The use of antidepressants is not the same as the diagnosis of depression. Because of the design, our results cannot permit any conclusion whether depression acts as an additional factor considered in decision-making in psychogeriatric patients. We suggest that depression and its correlates should be considered in discussions and studies about DNR.


Assuntos
Demência/mortalidade , Política Organizacional , Ordens quanto à Conduta (Ética Médica)/legislação & jurisprudência , Idoso , Idoso de 80 Anos ou mais , Antidepressivos/administração & dosagem , Demência/classificação , Demência/diagnóstico , Feminino , Hospitais de Ensino/legislação & jurisprudência , Humanos , Masculino , Países Baixos/epidemiologia , Admissão do Paciente/estatística & dados numéricos , Unidade Hospitalar de Psiquiatria/legislação & jurisprudência
17.
Ned Tijdschr Geneeskd ; 140(6): 304-8, 1996 Feb 10.
Artigo em Holandês | MEDLINE | ID: mdl-8720704

RESUMO

OBJECTIVE: To study the appropriateness of minimally invasive surgical treatment of primary hyperparathyroidism. DESIGN: Prospective. SETTING: University Hospital Utrecht, the Netherlands. METHOD: In patients with primary hyperparathyroidism, parathyroid adenomas were located preoperatively by means of Doppler assisted ultrasonography and spiral computer tomography. If the results were positive, minimally invasive surgery was performed. RESULTS: Minimally invasive surgery was carried out in 13 out of 15 successive patients with good results (the serum calcium and parathyroid hormone levels returned to normal). Two patients were subjected to conventional neck exploration, also with good results (preoperatively several adenomas were suspected in one, while no adenoma was seen in the other). CONCLUSION: It can be calculated that minimally invasive surgery will probably suffice in 60-70% of the patients with primary hyperparathyroidism, so that conventional neck exploration can be avoided.


Assuntos
Adenoma/diagnóstico , Hiperparatireoidismo/cirurgia , Neoplasias das Paratireoides/diagnóstico , Adenoma/diagnóstico por imagem , Adenoma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias das Paratireoides/diagnóstico por imagem , Neoplasias das Paratireoides/cirurgia , Paratireoidectomia/métodos , Estudos Prospectivos , Tomografia Computadorizada por Raios X , Ultrassonografia
18.
Eur J Clin Pharmacol ; 50(4): 321-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8803527

RESUMO

OBJECTIVES: The absolute bioavailability and other pharmacokinetic parameters of two fluoride formulations were investigated in 13 healthy volunteers, aged 61-70 years. METHODS: The following formulations were administered, under fasting conditions, in a single-dose three-way cross-over design: tablets of 76 mg disodium monofluoro phosphate (MFP, equivalent to 10.0 mg F- ion), enteric-coated (e.c.) tablets of 25 mg sodium fluoride (NaFor, equivalent of 11.3 mg F- ion), and an isoosmotic aqueous injection solution (4 ml) of 22.1 mg sodium fluoride (NaFiv, equivalent of 10.0 mg F- ion). There was a wash-out period of at least one week between each administration. Blood was sampled before and during a 24-hour period after administration. For F- excretion urine was sampled 48 hours before (baseline) and over the 48 hours after the administration. RESULTS: The mean t1/2 values of the three formulations were 8.3, 8.7 and 8.3 h for MFP, NaFor and NaFiv respectively, and were not significant different. Mean Cmax after MFP was significantly higher than after NaFor [344 vs 142 micrograms.l-1]. Mean tmax for MFP was shorter than for NaFor [1.1 vs 4.6 h]. MFP had significantly higher bioavailability [102.8%] than NaFor [64.2%]. CONCLUSION: The MFP formulation showed higher bioavailability with smaller variation than the NaFor formulation. MFP is preferable, therefore, for fluoride therapy in clinical practice, and changing from NaFor to MFP will require adjustment of the dose.


Assuntos
Fluoretos Tópicos/farmacocinética , Fluoretos/farmacocinética , Fosfatos/farmacocinética , Fluoreto de Sódio/farmacocinética , Administração Oral , Idoso , Análise de Variância , Disponibilidade Biológica , Estudos Cross-Over , Feminino , Fluoretos/sangue , Fluoretos/urina , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Fosfatos/sangue , Fosfatos/urina , Comprimidos com Revestimento Entérico
19.
J Bone Miner Res ; 10(6): 874-80, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7572311

RESUMO

This study was designed to investigate whether methotrexate (MTX), used in the treatment of rheumatoid arthritis (RA), affects proliferation and differentiation of human osteoblasts in culture. The effects of MTX were assessed by analyzing markers of proliferation and differentiation of human trabecular bone-derived osteoblast-like cells cultured in the presence or absence of 1,25-dihydroxyvitamin D3 (1,25[OH]2D3). Treatment of the osteoblastic cells with MTX resulted in a strong dose-dependent inhibition of cell proliferation with half maximal response at a dose of 30 nM. MTX did not interfere with cellular alkaline phosphatase (AP) activity, the number of cells expressing cytochemical AP, or basal osteocalcin production. Addition of 1,25(OH)2D3 to the cultures caused an enhanced AP expression and osteocalcin production coinciding with a decreased osteoblast proliferation. Coincubation of 1,25(OH)2D3 with MTX in doses > or = 100 nM further inhibited osteoblast growth and induced a significant stimulation of AP expression and activity, and production of osteocalcin above the values reached in the 1,25(OH)2D3 cultures. In conclusion, MTX proved to be a potent inhibitor of osteoblast proliferation but did not affect basal osteoblastic phenotypic expression. In the presence of the osteoblast differentiation-promoter, 1,25(OH)2D3, MTX further inhibited cell growth which was associated with enhanced AP activity and osteocalcin production. Thus, MTX may have profound effects on bone metabolism and remodeling by interfering with bone cell turnover.


Assuntos
Antirreumáticos/toxicidade , Calcitriol/farmacologia , Metotrexato/toxicidade , Osteoblastos/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Análise de Variância , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Remodelação Óssea/efeitos dos fármacos , Remodelação Óssea/fisiologia , Osso e Ossos/metabolismo , Bromodesoxiuridina/metabolismo , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Cabeça do Fêmur/citologia , Cabeça do Fêmur/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Metotrexato/uso terapêutico , Osteoblastos/citologia , Osteoblastos/enzimologia , Osteocalcina/biossíntese , Radioimunoensaio
20.
Maturitas ; 21(3): 237-43, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7616873

RESUMO

Endogenous growth factors may be involved in the prevention of bone loss by estrogen and progestins in postmenopausal women. The present study was performed to compare the action of estrogen/progestins on bone-derived cells with the effects of exogenously added purified growth factors. Human osteoblast-like (HOB) cells were incubated with 17 beta-estradiol (E2), progesterone (P), dydrogesterone (DD), 20 alpha-dihydroxydydrogesterone (DHD), with and without the growth factors, insulin-like growth factors-I/-II (IGF-I/-II) or transforming growth factor-beta type 1 (TGF-beta 1) for 24 h under serum-free conditions. Cell growth and DNA synthesis were assessed by spectophotometrical analysis of total cell number and immunochemical detection of BrdU incorporation, respectively. Compared with the sex steroids, incubation of the cells with IGF-I or TGF-beta 1 resulted in at least a two-fold increase of total HOB cell numbers. No difference in stimulating HOB growth was observed between IGF-II and the female sex steroids E2 and P. Combining IGF-I/-II or TGF-beta 1 with either E2 or P did not result in a significantly further increase in the human osteoblast-like cell growth. In conclusion, the bone anabolic growth factors, IGF-I and TGF-beta 1, may be more important regulators of osteoblast proliferation than the female sex steroids. An interaction of estrogen/gestagens with the growth factors IGF-I/-II or TGF-beta 1 was not evident from the growth of human bone-forming cells in short-term cultures.


Assuntos
Estradiol/farmacologia , Osteoblastos/citologia , Progestinas/farmacologia , Somatomedinas/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Idoso , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Didrogesterona/análogos & derivados , Didrogesterona/farmacologia , Feminino , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/farmacologia , Osteoblastos/efeitos dos fármacos , Progesterona/farmacologia
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