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1.
Osteoporos Int ; 29(10): 2251-2260, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29943190

RESUMO

Information regarding the prevalence and risk of osteoporosis among American Indian (AI) women is limited. This study showed that with increasing AI blood quantum, the prevalence of osteoporosis at the hip based on BMD T-scores decreased and this appeared to be independent of other risk factors. INTRODUCTION: This study was designed to investigate the effects of AI blood quantum (BQ) on osteoporosis prevalence and risk in a cohort of AI women in Oklahoma. METHODS: Women (n = 301), aged 50 years and older, were recruited to participate in the Oklahoma American Indian Women's Osteoporosis Study. Baseline bone density, fracture history, bone biochemical markers, and potential risk factors were assessed. Participants were stratified by AI BQ into BQ1 ≤ 25%, BQ2 = 25-49%, BQ3 = 50-74%, and BQ4 = 75-100%. The effects of BQ on the prevalence and risk of osteoporosis were evaluated. RESULTS: Based on T-scores, one in approximately eight women in the study was osteoporotic at one or more sites. The prevalence of osteoporosis decreased (p < 0.05) with increasing BQ, especially at the hip, trochanteric, and intertrochanter regions. No differences in bone-specific alkaline phosphatase and C-telopeptide were observed across BQ that could account for the differences in bone density. 25-OH vitamin D decreased with increasing BQ, but mean for each BQ1-4 was > 40 ng/mL. Fracture history did not differ across BQ, and though 52% of the population consumed less than the RDA for calcium, no effect of BQ was observed. CONCLUSIONS: In this cohort of women who identified as AI, greater Indian BQ was associated with a decrease in the prevalence of osteoporosis.


Assuntos
Indígenas Norte-Americanos/estatística & dados numéricos , Osteoporose Pós-Menopausa/etnologia , Idoso , Antropometria/métodos , Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Cálcio da Dieta/administração & dosagem , Estudos Transversais , Suplementos Nutricionais , Feminino , Humanos , Pessoa de Meia-Idade , Oklahoma/epidemiologia , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/etnologia , Fraturas por Osteoporose/fisiopatologia , Prevalência , Medição de Risco/métodos
2.
Calcif Tissue Int ; 94(4): 442-53, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24357047

RESUMO

Dietary supplementation of dried plum (DP) prevents bone loss and restores bone mass in osteopenic animal models. This study was designed to determine the effects of DP supplementation on bone metabolic activity over time using adult (6-month-old) male C57BL/6 mice (n = 40) receiving control (CON = AIN93 M) or CON+DP 25 % (w/w) diets for 4 or 12 weeks. After 4 weeks of treatment, animals consuming the DP diet had a higher whole-body bone mineral density, vertebral trabecular bone volume (BV/TV), and femoral cortical thickness compared to the CON animals. In the distal metaphysis of the femur, BV/TV was increased in the DP-treated animals, but only after 12 weeks. Bone histomorphometric analyses revealed that DP decreased osteoblast surface (67 %) and osteoclast surface (62 %) at 4 weeks, but these surfaces normalized to the CON animals by 12 weeks. Coincident with these changes, the mineralizing surface (MS/BS) and cancellous bone formation rate (BFR/BS) were reduced at 4 weeks in the DP group compared to the CON, but by 12 weeks of DP supplementation, BFR/BS (~twofold) and MS/BS (~1.7-fold) tended to be increased (p < 0.10). The relative abundance of RNA for key regulators of osteoblast and osteoclast differentiation and indicators of osteoblast activity were reduced in the DP group at 4 weeks with no difference between groups at 12 weeks. These results indicate that supplementing the diet with DP initially suppressed cancellous bone turnover, but a biphasic response occurs over time, resulting in a positive effect on bone mass and structure.


Assuntos
Osso e Ossos/efeitos dos fármacos , Extratos Vegetais/química , Prunus/química , Absorciometria de Fóton , Animais , Antioxidantes/química , Composição Corporal , Densidade Óssea , Doenças Ósseas Metabólicas/tratamento farmacológico , Medula Óssea/metabolismo , Osso e Ossos/metabolismo , Diferenciação Celular , Fêmur/patologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Glutationa Peroxidase/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Osteoclastos/citologia , Osteoporose/fisiopatologia , Estresse Oxidativo , Reação em Cadeia da Polimerase em Tempo Real , Propriedades de Superfície , Imagem Corporal Total , Microtomografia por Raio-X
3.
Health Promot Int ; 24(4): 353-62, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19828475

RESUMO

Integrated planning is a holistic approach to addressing the needs of local communities built on partnerships between those responsible for development, environmental quality and service provision. This study investigated the extent and key influences on the use of integrated planning to promote physical activity among six metropolitan councils in Melbourne Australia, which took part in the MetroACTIVE Project funded by the Victorian Health Promotion Foundation from 2005 to 2007. The evaluation entailed interviews conducted at the mid-term (N = 67) and completion (N = 50) of the project, and the review of relevant documents. Respondents included elected councillors, chief executive officers, officers from different council divisions and the project staff employed in each council. Three councils showed evidence of integrated planning for physical activity, whereas the remainder focused on the delivery of community participation programs. Leadership from senior management and an organizational culture that supported collaboration across council departments were prerequisites for integrated planning. Employment of a dedicated project officer with skills for engaging management and building partnerships within the organization was important. Barriers to integrated planning were a complex organization structure, high demands on the council due to a growing residential population and a poor climate among staff. Overall, integrated planning was found to be a viable approach for developing a coordinated approach to this issue involving the range of council services and functions. Ongoing strategies are needed to facilitate senior management commitment and organizational capacity for integrated planning, with leadership provided by departments responsible for infrastructure or corporate planning.


Assuntos
Meio Ambiente , Exercício Físico , Programas Governamentais/organização & administração , Promoção da Saúde/organização & administração , Governo Local , Austrália , Humanos , Desenvolvimento de Programas , Pesquisa Qualitativa
4.
Int J Clin Pract ; 62(11): 1753-68, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18795968

RESUMO

AIMS: Nicotine addiction is a complex, chronic condition with physiological and psychological/behavioural aspects that make smoking cessation extremely difficult. This paper reviews current recommendations for smoking cessation and the efficacy of pharmacotherapy and behavioural modification techniques, used either alone or in combination, for smoking cessation. RESULTS: Abstinence rates for pharmacotherapies range from approximately 16% to approximately 30% at 1-year follow-up, with efficacy odds ratios (ORs) compared with placebo of approximately 1.7 for nicotine replacement therapy (NRT), approximately 1.9 for bupropion sustained release and approximately 3.0 for varenicline. Behaviour modification therapies have achieved quit rates of between 8% and 43% for up to 1 year, with ORs in comparison to no treatment of between approximately 1.2 and approximately 2.2. No direct comparisons have been made between pharmacotherapy alone and psychological behaviour strategies alone. However, combining physiological approaches with counselling significantly increases the odds of quitting compared with either technique alone. CONCLUSIONS: Applying multimodal techniques for the treatment of nicotine addiction is the recommended approach and has demonstrated the potential to improve rates of permanent abstinence in smokers attempting cessation. While the numbers of patients receiving help and advice regarding smoking cessation is increasing, the multimodal approach appears to be currently underutilised by clinicians and therefore smoking cessation strategies are not being optimised.


Assuntos
Abandono do Hábito de Fumar/métodos , Prevenção do Hábito de Fumar , Tabagismo/prevenção & controle , Benzazepinas/uso terapêutico , Terapia Combinada , Terapias Complementares , Quimioterapia Combinada , Humanos , Nicotina/uso terapêutico , Agonistas Nicotínicos/uso terapêutico , Guias de Prática Clínica como Assunto , Psicoterapia/métodos , Quinoxalinas/uso terapêutico , Resultado do Tratamento , Vareniclina
5.
Osteoporos Int ; 18(7): 931-42, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17554580

RESUMO

UNLABELLED: Bone loss was confirmed after 90 days in 50 6-month-old male Sprague Dawley rats that were sham-operated or orchidectomized (ORX). In this study, we have shown that dried plum (DP) has potent effects on bone in terms of bone mass, microarchitecture, and strength in osteopenic male rats. Although these changes may be mediated through the suppression of bone resorption, the fact that the restoration in some of the bone structural and biomechanical parameter shares some similarities with parathyroid hormone (PTH) should not be overlooked. Further investigation is needed on a mechanistic level to clarify the influence of DP on bone metabolism. INTRODUCTION: This study was designed to investigate the extent to which DP reverses bone loss in osteopenic ORX rats and to compare its effects to PTH. MATERIALS AND METHODS: Fifty, 6-month-old male Sprague Dawley rats were sham-operated or ORX, and bone loss was confirmed after 90 days. The ORX groups were assigned to control (AIN-93M) diet, 25% DP diet, or PTH (80 microg/kg) for 90 days. RESULTS: DP induced an 11% increase in vertebral and femoral BMD compared to ORX-controls. BMD in the PTH-treated group was increased by 20.7% (vertebra) and 17.9% (femur). Vertebral trabecular bone volume (BV/TV) and number were increased by DP and trabecular separation was decreased compared to controls, which were similar to PTH. Alterations in trabecular bone of the femur were similar to those in the vertebra, but DP did not restore BV/TV to the same extent. Cortical thickness was improved by DP and further enhanced by PTH. DP tended to decrease urinary deoxypyridinoline and calcium, but did not alter alkaline phosphatase or osteocalcin. CONCLUSION: We conclude that though the degree of improvement was not equivalent to PTH with regard to all parameters, DP reverses bone loss due to ORX and the mechanisms should be further investigated.


Assuntos
Doenças Ósseas Metabólicas/dietoterapia , Doenças Ósseas Metabólicas/tratamento farmacológico , Suplementos Nutricionais , Orquiectomia , Hormônio Paratireóideo/farmacologia , Prunus , Absorciometria de Fóton , Animais , Biomarcadores , Fenômenos Biomecânicos , Peso Corporal , Doenças Ósseas Metabólicas/patologia , Fêmur/diagnóstico por imagem , Fêmur/patologia , Fêmur/fisiologia , Conservação de Alimentos , Masculino , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/patologia , Coluna Vertebral/fisiologia
6.
Bone ; 39(6): 1331-42, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16890505

RESUMO

Previously, dietary supplementation with dried plums, a rich source of polyphenolic compounds with antioxidant and anti-inflammatory properties, has been shown to improve bone density, microstructure and biomechanics in female animal models of osteopenia. We designed this study to determine the extent to which dried plum prevents skeletal deterioration in gonadal hormone deficient male animals and to begin to understand its mechanism of action. Sixty 6-month-old male Sprague-Dawley rats were either sham-operated (Sham = 1 group) or orchidectomized (ORX = 4 groups) and randomly assigned to dietary treatments: standard semi-purified diet (Control) with either LD = 5%, MD = 15%, or HD = 25% (w/w) dried plum for 90 days. At the end of the treatment period, both the MD and HD dried plum completely prevented the ORX-induced decrease in whole body, femur, and lumbar vertebra bone mineral density (BMD). Biomechanical testing indicated that the MD and HD of dried plum prevented the ORX-induced decrease in ultimate load of the cortical bone as well as the compressive force and stiffness of trabecular bone within the vertebrae. Analyses of trabecular microarchitecture of the distal femur metaphysis and vertebral body revealed that HD dried plum protected against the decrease in trabecular bone volume (BV/TV) induced by ORX. In the distal femur, all doses of dried plum improved trabecular number (TbN) and separation (TbSp) compared to the ORX-control group, while MD and HD dried plum prevented the ORX-induced changes in vertebral TbN and TbSp. At the end of the 90-day treatment, no remarkable changes in serum osteocalcin or alkaline phosphatase in any of the treatment groups were observed, while serum insulin-like growth factor (IGF)-I was increased by dried plum. The ORX-induced increase in urinary deoxypyridinoline (DPD) excretion was completely prevented by all doses of dried plum coinciding with down-regulation of gene expression for receptor activator of NFkappa-B ligand (RANKL) and osteoprotegerin (OPG) in the bone. We conclude that dried plum prevents osteopenia in androgen deficient male rats, and these beneficial effects may be attributed in part to a decrease in osteoclastogenesis via down-regulation of RANKL and stimulation of bone formation mediated by IGF-I.


Assuntos
Suplementos Nutricionais , Fator de Crescimento Insulin-Like I/metabolismo , Osteoporose/metabolismo , Osteoporose/prevenção & controle , Prunus , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Animais , Antioxidantes/administração & dosagem , Sequência de Bases , Fenômenos Biomecânicos , Densidade Óssea , Osso e Ossos/metabolismo , Feminino , Flavonoides/administração & dosagem , Expressão Gênica , Masculino , Osteoporose/genética , Osteoprotegerina/genética , Fenóis/administração & dosagem , Polifenóis , Ligante RANK/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley
7.
Bone ; 38(3): 378-86, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16256450

RESUMO

Clinically, osteopenia or low bone mass has been observed in a variety of chronic inflammatory diseases, and elevated proinflammatory mediators have implicated this process. The purpose of this study was to develop an in vivo model of bone loss induced by chronic systemic inflammation. Time-release pellets designed to deliver one of three doses of LPS: Low (3.3 microg/day), High (33.3 microg/day), or Placebo over 90 days, were implanted subcutaneously in 3-month-old male Sprague-Dawley rats (n = 8/group). Neutrophil counts, indicative of ongoing inflammation, were elevated (P < 0.05) in both LPS groups at 30 days post-implant and remained significantly elevated in the High dose throughout the 90-day study period. At the end of the study, bone loss occurred in the femur as indicated by decreased bone mineral density (BMD) in both LPS-treated groups, but vertebral BMD was reduced in the High dose animals only. Microcomputed tomography revealed that trabecular bone volume (BV/TV) of the proximal tibial metaphysis tended to be reduced in the High dose LPS group. Deleterious effects on trabecular number (TbN) and trabecular separation (TbSp) were observed in both LPS-treated groups, but only the High dose group reached statistical significance. These alterations in trabecular microarchitecture resulted in compromised biomechanical properties. No changes in cortical thickness, porosity, or area of the tibia midshaft were evident at either dose of LPS. Up-regulation of the proinflammatory mediators, cyclooxygenase (COX)-2, interleukin (IL)-1, and tumor necrosis factor (TNF)-alpha was demonstrated in the metaphyseal region where the deleterious effects of LPS were observed. In addition to these alterations in bone, trichrome staining indicated changes in the coronary arterioles, consistent with vascular disease. Utilization of a LPS time-release pellet appears to provide an in vivo model of chronic inflammation-induced bone loss and a potentially novel system to study concurrent development of osteopenia and vascular disease.


Assuntos
Doença das Coronárias/etiologia , Vasos Coronários/patologia , Modelos Animais de Doenças , Inflamação/patologia , Osteoporose/patologia , Ratos Sprague-Dawley , Absorciometria de Fóton , Animais , Fenômenos Biomecânicos , Densidade Óssea , Doença Crônica , Doença das Coronárias/patologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Fibrose/patologia , Imuno-Histoquímica , Lipopolissacarídeos/administração & dosagem , Lipopolissacarídeos/farmacologia , Masculino , Miocárdio/patologia , Osteoporose/complicações , Ratos , Tíbia/efeitos dos fármacos , Tíbia/metabolismo , Tomografia Computadorizada por Raios X
8.
Calcif Tissue Int ; 76(4): 272-9, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15742232

RESUMO

The deleterious effects of skeletal unloading on bone mass and strength may, in part, result from increased production of oxygen-derived free radicals and proinflammatory cytokines. This study was designed to evaluate the ability of vitamin E (alpha-tocopherol), a free-radical scavenger with antiinflammatory properties, to protect against bone loss caused by skeletal unloading in mature male Sprague-Dawley rats. A 2 x 3 factorial design was used with either hindlimb unloading (HU) or normal loading (ambulatory; AMB), and low-dose (LD; 15 IU/kg diet), adequate-dose (AD; 75 IU/kg diet), or high-dose (HD; 500 IU/kg diet) vitamin E (DL-alpha-tocopherol acetate). To optimize the effects of vitamin E on bone, dietary treatments were initiated 9 weeks prior to unloading and continued during the 4-week unloading period, at which time animals were euthanized and blood and tissue samples were collected. Serum vitamin E was dose-dependently increased, confirming the vitamin E status of animals. The HD treatment improved oxidation parameters, as indicated by elevated serum ferric-reducing ability and a trend toward reducing tissue lipid peroxidation. Histomorphometric analysis of the distal femur revealed significant reductions in trabecular thickness (TbTh), double-labeled surface (dLS/BS), and rate of bone formation to bone volume (BFR/BV) due by HU. AMB animals on the HD diet and HU animals on the LD diet had reduced bone surface normalized to tissue volume (BS/TV) and trabecular number (TbN); however, the HD vitamin E protected against these changes in the HU animals. Our findings suggest that vitamin E supplementation provides modest bone protective effects during skeletal unloading.


Assuntos
Antioxidantes/uso terapêutico , Desmineralização Patológica Óssea/tratamento farmacológico , Sequestradores de Radicais Livres/uso terapêutico , Elevação dos Membros Posteriores/fisiologia , Vitamina E/uso terapêutico , Animais , Biomarcadores/sangue , Desmineralização Patológica Óssea/etiologia , Desmineralização Patológica Óssea/metabolismo , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Peroxidação de Lipídeos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos , Ratos Sprague-Dawley , Tíbia/efeitos dos fármacos , Tíbia/metabolismo
9.
Phytomedicine ; 11(4): 303-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15185842

RESUMO

Recent reports indicate that ovariectomy (ovx) increases lymphopoiesis. Ipriflavone, a synthetic isoflavone, has been reported to reduce lymphocytes in postmenopausal women. The aim of this study was to investigate whether naturally occurring isoflavones also affect lymphopoiesis in ovarian hormone deficiency. The present study was carried out using an ovariectomized (ovx) rat model. To mimic early menopause, forty-eight 12-month-old Sprague-Dawley rats were either sham-operated (sham; 1 group) or ovx (3 groups) and were fed a standard semi-purified diet for 120 days. Thereafter, the ovx groups received one of the three doses of isoflavones: 0 (ovx), 500 (ISO500), or 1000 (ISO1000) mg/kg diet for 100 days. Ovariectomy increased total leukocyte counts significantly (p < 0.05) as a result of increased (p < 0.05) lymphocyte, monocyte, eosinophil, and basophil differential counts. Isoflavones at 500 and 1000 mg/kg diet returned the total leukocyte counts, as well as leukocyte subpopulations, to levels comparable to that of sham-operated rats. No other hematological parameters, e.g., red blood cell counts or red cell indices, were affected by ovariectomy or isoflavones. We conclude that soy isoflavones restore normal leukocyte counts elevated in ovarian hormone deficiency.


Assuntos
Glycine max , Isoflavonas/farmacologia , Leucócitos/efeitos dos fármacos , Fitoterapia , Animais , Dieta , Estradiol/deficiência , Feminino , Isoflavonas/administração & dosagem , Isoflavonas/uso terapêutico , Contagem de Leucócitos , Ovariectomia , Ratos , Ratos Sprague-Dawley
10.
Phytomedicine ; 11(7-8): 567-75, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15636169

RESUMO

Alternative and complementary therapeutic approaches, such as the use of a wide array of herbal, nutritional, and physical manipulations, are becoming popular for relieving symptoms of osteoarthritis (OA). The present study evaluated the efficacy of soy protein (SP) supplementation in relieving the pain and discomfort associated with OA. One hundred and thirty-five free-living individuals (64 men and 71 women) with diagnosed OA or with self-reported chronic knee joint pain not attributed to injury or rheumatoid arthritis were recruited for this double-blind, placebo-controlled, parallel design study. Study participants were assigned randomly to consume 40 g of either supplemental SP or milk-based protein (MP) daily for 3 months. Pain, knee range of motion, and overall physical activity were evaluated prior to the start of treatment and monthly thereafter. Serum levels of glycoprotein 39 (YKL-40), a marker of cartilage degradation, and insulin-like growth factor-I (IGF-I), a growth factor associated with cartilage synthesis, were assessed at baseline and at the end of the study. Overall, SP improved OA-associated symptoms such as range of motion and several factors associated with pain and quality of life in comparison to MP. However, these beneficial effects were mainly due to the effect of SP in men rather than women. Biochemical markers of cartilage metabolism further support the efficacy of SP in men as indicated by a significant increase in serum level of IGF-I and a significant decrease in serum level of YKL-40 compared to MP. This study is the first to provide evidence of possible beneficial effects of SP in the management of OA. Examining and verifying the long-term effects of SP on improving symptoms of OA, particularly in men, is warranted.


Assuntos
Osteoartrite/tratamento farmacológico , Proteínas de Soja/uso terapêutico , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/complicações , Dor/tratamento farmacológico , Dor/etiologia , Qualidade de Vida
11.
Structure ; 9(3): 255-66, 2001 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-11286892

RESUMO

BACKGROUND: Membrane fusion within the Paramyxoviridae family of viruses is mediated by a surface glycoprotein termed the "F", or fusion, protein. Membrane fusion is assumed to involve a series of structural transitions of F from a metastable (prefusion) state to a highly stable (postfusion) state. No detail is available at the atomic level regarding the metastable form of these proteins or regarding the transitions accompanying fusion. RESULTS: The three-dimensional structure of the fusion protein of Newcastle disease virus (NDV-F) has been determined. The trimeric NDV-F molecule is organized into head, neck, and stalk regions. The head is comprised of a highly twisted beta domain and an additional immunoglobulin-like beta domain. The neck is formed by the C-terminal extension of the heptad repeat region HR-A, capped by a four-helical bundle. The C terminus of HR-A is encased by a further helix HR-C and a 4-stranded beta sheet. The stalk is formed by the remaining visible portion of HR-A and by polypeptide immediately N-terminal to the C-terminal heptad repeat region HR-B. An axial channel extends through the head and neck and is fenestrated by three large radial channels located approximately at the head-neck interface. CONCLUSION: We propose that prior to fusion activation, the hydrophobic fusion peptides in NDV-F are sequestered within the radial channels within the head, with the central HR-A coiled coil being only partly formed. Fusion activation then involves, inter alia, the assembly of a complete HR-A coiled coil, with the fusion peptides and transmembrane anchors being brought into close proximity. The structure of NDV-F is fundamentally different than that of influenza virus hemagglutinin, in that the central coiled coil is in the opposite orientation with respect to the viral membrane.


Assuntos
Vírus da Doença de Newcastle/química , Proteínas Virais de Fusão/química , Sequência de Aminoácidos , Cristalografia por Raios X , Fusão de Membrana , Dados de Sequência Molecular , Estrutura Quaternária de Proteína , Alinhamento de Sequência
12.
Teratology ; 62(6): 413-9, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11091363

RESUMO

BACKGROUND: Maternal immune stimulation has reported, but unconfirmed, efficacy for reducing chemical-induced morphologic defects in mice. METHODS: Teratogenic chemicals (2,3,7, 8-tetrachlorodibenzo-p-dioxin [TCDD], ethyl carbamate [urethane], methylnitrosourea [MNU], or valproic acid [VA]) were given to pregnant mice to induce cleft palate (TCDD, urethane), digital defects (urethane, MNU), or exencephaly (VA). Before teratogen administration, the immune system of female mice was stimulated by intraperitoneal (IP) administration of pyran copolymer or attenuated bacillus Calmette Guérin (BCG), or by footpad injection with Freund's complete adjuvant (FCA). RESULTS: Fetal defects caused by all four chemicals studied were reduced by maternal immunostimulation, sometimes dramatically. In addition to reducing VA-induced exencephaly, immunostimulation with FCA resulted in fetal mice displaying anury (absence of tails). Activated maternal immune cells could not be detected in fetal circulation using flow cytometry and a fluorescent cell-tracking probe. CONCLUSIONS: For the chemicals tested, maternal immune stimulation has efficacy in reducing fetal defects. Immune protection against teratogenesis may be an indirect effect of maternal immune cell activation.


Assuntos
Anormalidades Induzidas por Medicamentos/prevenção & controle , Anormalidades Múltiplas/prevenção & controle , Adjuvantes Imunológicos/uso terapêutico , Vacina BCG/uso terapêutico , Adjuvante de Freund/uso terapêutico , Metilnitrosoureia/toxicidade , Dibenzodioxinas Policloradas/toxicidade , Gravidez/imunologia , Copolímero de Pirano/uso terapêutico , Teratogênicos/toxicidade , Uretana/toxicidade , Ácido Valproico/toxicidade , Anormalidades Induzidas por Medicamentos/embriologia , Anormalidades Induzidas por Medicamentos/etiologia , Anormalidades Múltiplas/embriologia , Anormalidades Múltiplas/etiologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Vacina BCG/administração & dosagem , Vacina BCG/imunologia , Fissura Palatina/induzido quimicamente , Fissura Palatina/prevenção & controle , Cruzamentos Genéticos , Feminino , Sangue Fetal/citologia , Citometria de Fluxo , , Adjuvante de Freund/administração & dosagem , Adjuvante de Freund/imunologia , Injeções , Injeções Intraperitoneais , Deformidades Congênitas dos Membros/induzido quimicamente , Deformidades Congênitas dos Membros/prevenção & controle , Troca Materno-Fetal , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Defeitos do Tubo Neural/induzido quimicamente , Defeitos do Tubo Neural/prevenção & controle , Copolímero de Pirano/administração & dosagem
13.
Teratology ; 62(6): 420-8, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11091364

RESUMO

BACKGROUND: Maternal immune stimulation reduces malformations caused by chemical teratogens. Mechanisms for this effect are not known. Altered expression of regulatory molecules (e.g., transforming growth factor [TGF-beta], tumor necrosis factor-alpha [TNF-alpha]) has been reported in fetuses from immunostimulated mice, which may affect gene expression. Expression of selected genes that function to control proliferation, differentiation, or apoptosis was evaluated in chemical-exposed fetuses, with or without maternal immunostimulation. METHODS: Ethyl carbamate (urethane) was given to pregnant ICR mice on day 10 of gestation to induce cleft palate. Before teratogen administration, the immune system of the female mice was stimulated by footpad injection with Freund's complete adjuvant (FCA) or by intraperitoneal injection with interferon-gamma (IFN-gamma). RESULTS: Maternal immunostimulation with interferon-gamma (IFN-gamma) decreased severity of the cleft palate lesion caused by urethane, while FCA decreased both incidence and severity of cleft palate. Gestation day 14 fetuses from urethane-exposed mothers displayed decreased expression of cell cycle/apoptotic genes bcl2alpha, bcl2beta, pkCalpha, and p53 in fetal heads. Immune stimulation with IFN-gamma-normalized expression of bcl2alpha, bcl2beta, and pkCalpha to control levels. Urethane also decreased the ratio of expression of bclalpha/p53, bclbeta/p53, and pkCalpha/p53, while maternal injection with IFN-gamma restored these expression ratios to control levels. Maternal immunization with FCA also significantly increased bcl2alpha/p53, bcl2beta/p53, and pkCalpha/p53 gene expression ratios. CONCLUSIONS: These results suggest that (1) the maternal immune system may possess heretofore unrecognized regulatory activity in fetal development, and (2) protection against urethane-induced cleft palate may be mediated through maternal immune regulation of fetal gene expression.


Assuntos
Anormalidades Induzidas por Medicamentos/prevenção & controle , Adjuvantes Imunológicos/farmacologia , Fissura Palatina/prevenção & controle , Adjuvante de Freund/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Interferon gama/farmacologia , Gravidez/imunologia , Teratogênicos/toxicidade , Uretana/toxicidade , Anormalidades Induzidas por Medicamentos/genética , Adjuvantes Imunológicos/uso terapêutico , Animais , Apoptose/genética , Ciclo Celular/genética , Fissura Palatina/induzido quimicamente , Fissura Palatina/embriologia , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Desenvolvimento Embrionário e Fetal/genética , Feminino , Proteínas Fetais/genética , , Adjuvante de Freund/administração & dosagem , Adjuvante de Freund/uso terapêutico , Genes bcl-2 , Genes p53 , Injeções , Injeções Intraperitoneais , Interferon gama/administração & dosagem , Interferon gama/uso terapêutico , Isoenzimas/genética , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteína Quinase C/genética , Proteína Quinase C-alfa , RNA Mensageiro/análise , Receptores do Ácido Retinoico/genética , Receptores X de Retinoides , Fatores de Transcrição/genética
14.
Respirology ; 4(2): 101-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10382227

RESUMO

The objective was to assess the association between asthma and/or chronic obstructive airway diseases (COAD), and osteoporosis, and appraise treatments of osteoporosis in these patients. MEDLINE and Excerpta Medica were searched for original research with control groups which tested the above association. One cohort and nine cross-section studies of bone density in patients with asthma and/or COAD were retrieved. These demonstrated clinically important bone density reductions of up to 29% in subjects, dependent upon daily oral corticosteroids, by a variety of measurement techniques, at various bone sites. Bone density reduction has also been less consistently reported in the absence of oral corticosteroids, suggesting that other factors including high-dose inhaled corticosteroids may have a role. Fracture studies. Three studies in oral corticosteroid-dependent asthmatics demonstrated a vertebral fracture prevalence up to 56%, and annual vertebral fracture incidence of up to 42%. The strength of the available evidence is limited, but suggests that patients with asthma and/or COAD are at increased risk of osteoporosis. The evidence of the association between osteoporosis and inhaled corticosteroids is much more limited than for oral corticosteroids. Bisphosphonates are promising agents to maintain and/or promote bone mass in this patient group.


Assuntos
Asma/complicações , Fraturas Ósseas/etiologia , Pneumopatias Obstrutivas/complicações , Osteoporose/etiologia , Administração por Inalação , Administração Oral , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/efeitos adversos , Asma/tratamento farmacológico , Densidade Óssea , Estudos de Coortes , Estudos Transversais , Fraturas Ósseas/epidemiologia , Humanos , Incidência , Pneumopatias Obstrutivas/tratamento farmacológico , Osteoporose/epidemiologia , Osteoporose/patologia , Osteoporose/terapia , Prevalência , Fatores de Risco , Esteroides , Resultado do Tratamento
15.
Arch Ophthalmol ; 114(11): 1376-81, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8906028

RESUMO

BACKGROUND: Combined modality therapy for childhood retinoblastoma holds the potential of decreasing treatment-related morbidity while maintaining excellent tumor control rates. OBJECTIVE: To evaluate the efficacy of external beam radiation therapy (EBRT), ferromagnetic hyperthermia (FMH), and the combination of both modalities in the control of ocular tumors in a transgenic murine model of retinoblastoma. METHODS: One hundred sixty-six mouse eyes from 4-week-old animals transgenically positive for simian virus 40 large T antigen were treated with a total dose of 10, 15, 20, 30, 40, 45, or 50 Gy of EBRT in 5-Gy fractions twice daily, with 48 degrees C or 54 degrees C FMH for 20 minutes, or with combined EBRT at 10 or 30 Gy and 48 degrees C or 54 degrees C FMH for 20 minutes. Serial histologic sections, obtained 8 weeks after treatment, were examined for the presence of tumor. RESULTS: The tumor control dose for 50% of eyes (TCD50) treated with EBRT occurred at 27.6 Gy. Ferromagnetic hyperthermia at 48 degrees C cured 30% (6/20) of eyes, while 54 degrees C FMH resulted in a 100% (20/20) cure rate. Combined treatment with 48 degrees C FMH and EBRT exhibited a TCD50 at 3.3 Gy. The thermal enhancement ratio was 8.4. Ferromagnetic hyperthermia at 54 degrees C exhibited tumor cure in all animals, but 25% of eyes were lost owing to secondary treatment complications. CONCLUSIONS: This represents the first documentation of tumor control via EBRT, ocular FMH, and a combination of these treatment modalities in this murine transgenic retinoblastoma model. The extent of treatment synergy in this model suggests that combined treatment application may allow a reduction in total ocular and periocular radiation dose while maintaining excellent local tumor control.


Assuntos
Neoplasias Oculares/terapia , Hipertermia Induzida , Radioterapia de Alta Energia , Retinoblastoma/terapia , Animais , Antígenos Transformantes de Poliomavirus/genética , Terapia Combinada , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Neoplasias Oculares/genética , Neoplasias Oculares/patologia , Genes do Retinoblastoma/genética , Temperatura Alta , Ferro , Magnetismo , Camundongos , Camundongos Transgênicos/genética , Dosagem Radioterapêutica , Retinoblastoma/genética , Retinoblastoma/patologia
16.
Aust N Z J Med ; 24(4): 396-401, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7980237

RESUMO

BACKGROUND: Patients with chronic obstructive airways disease and asthma are at special risk of developing osteoporosis. Previous research has indicated that adrenal androgen levels in postmenopausal women are suppressed by short term high dose inhaled corticosteroids. Such an effect, if sustained, may be a causative factor for long term bone loss. We tested the hypothesis that postmenopausal women receiving > or = 1 mg/day inhaled beclomethasone dipropionate, long term, have suppressed dehydroepiandrosterone sulphate levels when compared to postmenopausal controls. METHODS: As part of a larger study, we studied 36 postmenopausal subjects, recruited from regional pharmacies and a hospital chest clinic, who had been receiving treatment for asthma. Subjects were selected if they were receiving > or = 1 mg/day inhaled beclomethasone dipropionate (n = 27) or receiving no beclomethasone dipropionate (n = 9). The two groups were compared for dehydroepiandrosterone sulphate levels, age and potential confounders. RESULTS: Mean dehydroepiandrosterone sulphate levels were 35% lower in the high dose beclomethasone dipropionate group than the control group (p < 0.01). CONCLUSIONS: This is the first report of suppression of dehydroepiandrosterone sulphate in postmenopausal women receiving long term inhaled beclomethasone dipropionate. Further research is needed to clarify whether or not there is any associated clinically important adverse effect on bone density.


Assuntos
Beclometasona/administração & dosagem , Desidroepiandrosterona/análogos & derivados , Pós-Menopausa/efeitos dos fármacos , Distribuição por Idade , Idoso , Asma/sangue , Asma/tratamento farmacológico , Asma/epidemiologia , Fatores de Confusão Epidemiológicos , Desidroepiandrosterona/antagonistas & inibidores , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Radioimunoensaio , Análise de Regressão , Resultado do Tratamento
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