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1.
Osteoporos Int ; 30(8): 1573-1580, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31143993

RESUMO

Since stress fractures are common among adolescent athletes, it is important to identify bone assessment tools that accurately identify risk. We investigated the discriminative ability of two imaging technologies to classify at-risk athletes. Findings suggested that peripheral quantitative computed tomography (pQCT) has the ability to distinguish differences in bone structure in injured vs. uninjured limbs. INTRODUCTION: Given the high stress fracture (SFX) prevalence among adolescent girls, an understanding of the most informative assessment tools to identify SFX risks are required. We investigated the discriminative ability of pQCT vs. dual-energy X-ray absorptiometry (DXA) to classify athletes with or without SFX. METHODS: Twelve adolescent athletes diagnosed with a lower-extremity SFX were compared with 12 matched controls. DXA measured areal bone mineral density (aBMD) and content of the total body, and lumbar spine. Bilateral tibiae were assessed with pQCT. At the metaphysis (3%), total density (ToD), trabecular density (TrD), trabecular area (TrA), and estimated bone strength in compression (BSIc), and at the diaphysis (38% and 66%), total bone area (ToA), cortical density (CoD), cortical area (CoA), estimated bone strength in torsion (SSIp), and peri- and endocortical and muscle area (MuA) were obtained. Cortical bone mass/density around the center of mass and marrow density (estimate of adiposity) were calculated using ImageJ software. General estimated equations adjusting for multiple comparisons (Holm-Bonferroni method) were used to compare means between (1) injured limb of the case athletes vs. uninjured limb of the control athletes and (2) uninjured limb of the case athletes vs. uninjured limbs of the controls and injured vs. uninjured limb of case athletes with a SFX. RESULTS: aBMD and content showed no significant differences between cases and controls. When comparing the injured vs. uninjured leg in the case athletes by pQCT at the 3% tibia, unadjusted TrD, total density, and BSIc were significantly lower (p < 0.05) in the injured vs. uninjured leg. Marrow density at the 66% site was 1% (p < 0.05) lower in the injured vs. uninjured leg. CONCLUSIONS: These preliminary data in athletes with SFX suggest that pQCT has the ability to distinguish differences in bone structure in injured vs. uninjured limbs. No discriminative bone parameter classifications were identified between adolescent athletes with or without SFX.


Assuntos
Traumatismos em Atletas/diagnóstico por imagem , Fraturas de Estresse/diagnóstico por imagem , Absorciometria de Fóton/métodos , Adolescente , Antropometria/métodos , Traumatismos em Atletas/fisiopatologia , Densidade Óssea/fisiologia , Estudos de Casos e Controles , Criança , Feminino , Fraturas de Estresse/fisiopatologia , Humanos , Traumatismos da Perna/diagnóstico por imagem , Traumatismos da Perna/fisiopatologia , Extremidade Inferior/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Projetos Piloto , Medição de Risco/métodos
2.
Osteoporos Int ; 28(4): 1255-1263, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27909781

RESUMO

We sought to determine whether low-magnitude mechanical stimulation (LMMS) normalizes bone turnover among adolescents hospitalized for anorexia nervosa (AN). Brief, daily LMMS prevents the decline in bone turnover typically seen during bed rest in AN. LMMS may have application for patients with AN in the inpatient setting to protect bone health. INTRODUCTION: Malnourished adolescents with AN requiring medical hospitalization are at high risk for rapid reduction in skeletal quality. Even short-term bed rest can suppress normal patterns of bone turnover. We sought to determine whether LMMS normalizes bone turnover among adolescents hospitalized for complications of AN. METHODS: In this randomized, double-blind trial, we prospectively enrolled adolescent females (n = 41) with AN, age 16.3 ± 1.9 years (mean ± SD) and BMI 15.6 ± 1.7 kg/m2. Participants were randomized to stand on a platform delivering LMMS (0.3 g at 32-37 Hz) or placebo platform for 10 min/day for 5 days. Serum markers of bone formation [bone-specific alkaline phosphatase (BSAP)], turnover [osteocalcin (OC)], and bone resorption [serum C-telopeptides (CTx)] were measured. From a random coefficients model, we constructed estimates and confidence intervals for all outcomes. RESULTS: BSAP decreased by 2.8% per day in the placebo arm (p = 0.03) but remained stable in the LMMS group (p = 0.51, pdiff = 0.04). CTx did not change with placebo (p = 0.56) but increased in the LMMS arm (+6.2% per day, p = 0.04; pdiff = 0.01). Serum OC did not change in either group (p > 0.70). CONCLUSIONS: Bed rest during hospitalization for patients with AN is associated with a suppression of bone turnover, which may contribute to diminished bone quality. Brief, daily LMMS prevents a decline in bone turnover during bed rest in AN. Protocols prescribing strict bed rest may not be appropriate for protecting bone health for these patients. LMMS may have application for these patients in the inpatient setting.


Assuntos
Anorexia Nervosa/complicações , Remodelação Óssea/fisiologia , Osteoporose/etiologia , Osteoporose/prevenção & controle , Vibração/uso terapêutico , Adolescente , Anorexia Nervosa/fisiopatologia , Repouso em Cama/efeitos adversos , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Hospitalização , Humanos , Osteoporose/fisiopatologia , Estimulação Física/métodos , Adulto Jovem
3.
Osteoporos Int ; 27(12): 3549-3558, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27392467

RESUMO

We conducted the first comparison of dual-energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT) outcomes in adolescent girls with anorexia nervosa. We observed deficits in bone density by both tools. pQCT assessments were associated with many of the same clinical parameters as have been previously established for DXA. INTRODUCTION: Adolescents with anorexia nervosa (AN) commonly exhibit bone loss, but effects on bone geometry are less clear. We compared measures obtained by DXA and pQCT in girls with AN. METHODS: Seventy females (age 15.5 ± 1.9 years ) with AN and 132 normal-weighted controls underwent tibial measures by pQCT including trabecular volumetric bone mineral density (vBMD) at the 3 % site, cortical vBMD and dimensions at the 38 % site, and muscle cross-sectional area (CSA) at the 66 % site. Participants with AN also underwent standard DXA measures. Independent t tests compared the pQCT results, while Pearson coefficient assessed correlations among DXA and pQCT measures. RESULTS: Trabecular vBMD Z-scores were lower in AN compared to controls (AN -0.31 ± 1.42 vs +0.11 ± 1.01, p = 0.01) and cortical vBMD Z-scores were higher (AN +0.18 ± 0.92 vs -0.50 ± 0.88, p < 0.001). Trabecular vBMD and cortical CSA Z-scores positively correlated with DXA BMD Z-scores (r range 0.57-0.82, p < 0.001). Markers of nutritional status positively correlated with Z-scores for trabecular vBMD, cortical CSA, section modulus, and muscle CSA (p < 0.04 for all). CONCLUSIONS: This study is the first to compare DXA and pQCT measurements in adolescent girls with AN. We observed deficits in BMD by both DXA and pQCT. pQCT assessments correlated well with DXA bone and body composition measures and were associated with many of the same clinical parameters and disease severity markers as have been previously established for DXA. The differences in cortical vBMD merit further study.


Assuntos
Anorexia Nervosa/patologia , Densidade Óssea , Tíbia/patologia , Absorciometria de Fóton , Adolescente , Estudos de Casos e Controles , Feminino , Humanos , Tomografia Computadorizada por Raios X
4.
Osteoporos Int ; 27(4): 1281-1386, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26856587

RESUMO

Lifestyle choices influence 20-40 % of adult peak bone mass. Therefore, optimization of lifestyle factors known to influence peak bone mass and strength is an important strategy aimed at reducing risk of osteoporosis or low bone mass later in life. The National Osteoporosis Foundation has issued this scientific statement to provide evidence-based guidance and a national implementation strategy for the purpose of helping individuals achieve maximal peak bone mass early in life. In this scientific statement, we (1) report the results of an evidence-based review of the literature since 2000 on factors that influence achieving the full genetic potential for skeletal mass; (2) recommend lifestyle choices that promote maximal bone health throughout the lifespan; (3) outline a research agenda to address current gaps; and (4) identify implementation strategies. We conducted a systematic review of the role of individual nutrients, food patterns, special issues, contraceptives, and physical activity on bone mass and strength development in youth. An evidence grading system was applied to describe the strength of available evidence on these individual modifiable lifestyle factors that may (or may not) influence the development of peak bone mass (Table 1). A summary of the grades for each of these factors is given below. We describe the underpinning biology of these relationships as well as other factors for which a systematic review approach was not possible. Articles published since 2000, all of which followed the report by Heaney et al. [1] published in that year, were considered for this scientific statement. This current review is a systematic update of the previous review conducted by the National Osteoporosis Foundation [1]. [Table: see text] Considering the evidence-based literature review, we recommend lifestyle choices that promote maximal bone health from childhood through young to late adolescence and outline a research agenda to address current gaps in knowledge. The best evidence (grade A) is available for positive effects of calcium intake and physical activity, especially during the late childhood and peripubertal years-a critical period for bone accretion. Good evidence is also available for a role of vitamin D and dairy consumption and a detriment of DMPA injections. However, more rigorous trial data on many other lifestyle choices are needed and this need is outlined in our research agenda. Implementation strategies for lifestyle modifications to promote development of peak bone mass and strength within one's genetic potential require a multisectored (i.e., family, schools, healthcare systems) approach.


Assuntos
Densidade Óssea/fisiologia , Desenvolvimento Ósseo/fisiologia , Estilo de Vida , Osteoporose/prevenção & controle , Absorciometria de Fóton/métodos , Envelhecimento/fisiologia , Composição Corporal/fisiologia , Medicina Baseada em Evidências/métodos , Exercício Físico/fisiologia , Humanos , Fenômenos Fisiológicos da Nutrição/fisiologia , Fraturas por Osteoporose/prevenção & controle , Tomografia Computadorizada por Raios X/métodos , Suporte de Carga/fisiologia
5.
Osteoporos Int ; 27(8): 2497-505, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26952010

RESUMO

UNLABELLED: Young adults with cystic fibrosis have compromised plate-like trabecular microstructure, altered axial alignment of trabeculae, and reduced connectivity between trabeculae that may contribute to the reduced bone strength and increased fracture risk observed in this patient population. INTRODUCTION: The risk of fracture is increased in patients with cystic fibrosis (CF). Individual trabecular segmentation (ITS)-based morphological analysis of high-resolution peripheral quantitative computed tomography (HR-pQCT) images segments trabecular bone into individual plates and rods of different alignment and connectivity, which are important determinants of trabecular bone strength. We sought to determine whether alterations in ITS variables are present in patients with CF and may help explain their increased fracture risk. METHODS: Thirty patients with CF ages 18-40 years underwent DXA scans of the hip and spine and HR-pQCT scans of the radius and tibia with further assessment of trabecular microstructure by ITS. These CF patients were compared with 60 healthy controls matched for age (±2 years), race, and gender. RESULTS: Plate volume fraction, thickness, and density as well as plate-plate and plate-rod connectivity were reduced, and axial alignment of trabeculae was lower in subjects with CF at both the radius and the tibia (p < 0.05 for all). At the radius, adjustment for BMI eliminated most of these differences. At the tibia, however, reductions in plate volume fraction and number, axially aligned trabeculae, and plate-plate connectivity remained significant after adjustment for BMI alone and for BMI and aBMD (p < 0.05 for all). CONCLUSIONS: Young adults with CF have compromised plate-like and axially aligned trabecular morphology and reduced connectivity between trabeculae. ITS analysis provides unique information about bone integrity, and these trabecular deficits may help explain the increased fracture risk in adults with CF not accounted for by BMD and/or traditional bone microarchitecture measurements.


Assuntos
Densidade Óssea , Fibrose Cística/fisiopatologia , Rádio (Anatomia)/patologia , Tíbia/patologia , Absorciometria de Fóton , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adulto Jovem
6.
Osteoporos Int ; 26(12): 2723-42, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26412214

RESUMO

This narrative review summarizes the role that nutrition plays in the development and maintenance of a healthy skeleton throughout the life-course. Nutrition has a significant influence on bone health throughout the life cycle. This narrative review summarizes current knowledge and guidance pertaining to the development and maintenance of a healthy skeleton. The primary objectives proposed for good bone health at the various stages of life are the following: Children and adolescents: achieve genetic potential for peak bone mass Adults: avoid premature bone loss and maintain a healthy skeleton Seniors: prevention and treatment of osteoporosis Findings from cohort studies, randomized controlled trials, systematic reviews and meta-analyses, in addition to current dietary guidelines, are summarized with the intention of providing clear nutritional guidance for these populations and pregnant women.


Assuntos
Fenômenos Fisiológicos da Nutrição/fisiologia , Desenvolvimento Ósseo/fisiologia , Cálcio/administração & dosagem , Criança , Fenômenos Fisiológicos da Nutrição Infantil/fisiologia , Dieta , Feminino , Interação Gene-Ambiente , Humanos , Fenômenos Fisiológicos da Nutrição Materna/fisiologia , Osteoporose/fisiopatologia , Osteoporose/prevenção & controle , Gravidez , Cuidado Pré-Natal/métodos , Caracteres Sexuais , Vitamina D/administração & dosagem
7.
Osteoporos Int ; 24(2): 501-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22525982

RESUMO

SUMMARY: This study evaluated bone health in adults with galactosemia. Associations between bone mineral density (BMD) and nutritional and biochemical variables were explored. Calcium level predicted hip and spine BMD, and gonadotropin levels were inversely associated with spinal BMD in women. These results afford insights into management strategies for these patients. INTRODUCTION: Bone loss is a complication of galactosemia. Dietary restriction, primary ovarian insufficiency in women, and disease-related alterations of bone metabolism may contribute. This study examined relationships between clinical factors and BMD in patients with galactosemia. METHODS: This cross-sectional sample included 33 adults (16 women) with classic galactosemia, mean age 32.0 ± 11.8 years. BMD was measured by dual-energy X-ray absorptiometry, and was correlated with age, height, weight, fractures, nutritional factors, hormonal status, and bone biomarkers. RESULTS: There was a significant difference in hip BMD between women and men (0.799 vs. 0.896 g/cm(2), p = 0.014). The percentage of subjects with BMD-Z <-2.0 was also greater for women than men [33 vs. 18 % (spine), 27 vs. 6 % (hip)], and more women reported sustaining fractures. Bivariate analyses yielded correlations between BMI and BMD-Z [at the hip in women (r = 0.58, p < 0.05) and spine in men (r = 0.53, p < 0.05)]. In women, weight was also correlated with BMD-Z (r = 0.57, p < 0.05 at hip), and C-telopeptides (r = -0.59 at spine and -0.63 hip, p < 0.05) and osteocalcin (r = -0.71 at spine and -0.72 hip, p < 0.05) were inversely correlated with BMD-Z. In final regression models, higher gonadotropin levels were associated with lower spinal BMD in women (p = 0.017); serum calcium was a significant predictor of hip (p = 0.014) and spine (p = 0.013) BMD in both sexes. CONCLUSIONS: Bone density in adults with galactosemia is low, indicating the potential for increased fracture risk, the etiology of which appears to be multifactorial.


Assuntos
Galactosemias/complicações , Osteoporose/etiologia , Absorciometria de Fóton/métodos , Adulto , Antropometria/métodos , Biomarcadores/sangue , Densidade Óssea/fisiologia , Cálcio/administração & dosagem , Cálcio/sangue , Estudos Transversais , Suplementos Nutricionais , Esquema de Medicação , Feminino , Galactosemias/sangue , Galactosemias/fisiopatologia , Articulação do Quadril/fisiopatologia , Hormônios/sangue , Humanos , Masculino , Osteoporose/sangue , Osteoporose/fisiopatologia , Fatores Sexuais , Vitamina D/administração & dosagem , Adulto Jovem
11.
Bone ; 125: 103-111, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31077852

RESUMO

PURPOSE: Children with Hutchinson-Gilford progeria syndrome (HGPS), a rare premature aging disease, exhibit extraskeletal calcifications detected by radiographic analysis and on physical examination. The aim of this study was to describe the natural history and pathophysiology of these abnormal calcifications in HGPS, and to determine whether medications and/or supplements tested in clinical trials alter their development. METHODS: Children from two successive clinical trials administering 1) lonafarnib (n = 26) and 2) lonafarnib + pravastatin + zoledronic acid (n = 37) were studied at baseline (pre-therapy), one year on therapy, and at end-of-therapy (3.3-4.3 years after the baseline visit). Calcium supplementation (oral calcium carbonate) was administered during the first year of the second trial and was subsequently discontinued. Information on calcifications was obtained from physical examinations, radiographs, and serum and urinary biochemical measures. The mineral content of two skin-derived calcifications was determined by x-ray diffraction. RESULTS: Extraskeletal calcifications were detected radiographically in 12/39 (31%) patients at baseline. The odds of exhibiting calcifications increased with age (p = 0.045). The odds were unaffected by receipt of lonafarnib, pravastatin, and zoledronate therapies. However, administration of calcium carbonate supplementation, in conjunction with all three therapeutic agents, significantly increased the odds of developing calcifications (p = 0.009), with the odds plateauing after the supplement's discontinuation. Composition analysis of calcinosis cutis showed hydroxyapatite similar to bone. Although serum calcium, phosphorus, and parathyroid hormone (PTH) were within normal limits at baseline and on-therapy, PTH increased significantly after lonafarnib initiation (p < 0.001). Both the urinary calcium/creatinine ratio and tubular reabsorption of phosphate (TRP) were elevated at baseline in 22/39 (56%) and 31/37 (84%) evaluable patients, respectively, with no significant changes while on-therapy. The mean calcium × phosphorus product (Ca × Pi) was within normal limits, but plasma magnesium decreased over both clinical trials. Fibroblast growth factor 23 (FGF23) was lower compared to age-matched controls (p = 0.03). CONCLUSIONS: Extraskeletal calcifications increased with age in children with HGPS and were composed of hydroxyapatite. The urinary calcium/creatinine ratio and TRP were elevated for age while FGF23 was decreased. Magnesium decreased and PTH increased after lonafarnib therapy which may alter the ability to mobilize calcium. These findings demonstrate that children with HGPS with normal renal function and an unremarkable Ca × Pi develop extraskeletal calcifications by an unidentified mechanism that may involve decreased plasma magnesium and FGF23. Calcium carbonate accelerated their development and is, therefore, not recommended for routine supplementation in these children.


Assuntos
Calcinose/patologia , Progéria/patologia , Calcinose/sangue , Calcinose/diagnóstico por imagem , Calcinose/tratamento farmacológico , Cálcio/sangue , Criança , Pré-Escolar , Creatinina/sangue , Feminino , Fator de Crescimento de Fibroblastos 23 , Humanos , Técnicas In Vitro , Lamina Tipo A/metabolismo , Masculino , Hormônio Paratireóideo/sangue , Hormônio Paratireóideo/metabolismo , Piperidinas/uso terapêutico , Pravastatina/uso terapêutico , Progéria/sangue , Progéria/diagnóstico por imagem , Progéria/tratamento farmacológico , Piridinas/uso terapêutico , Ácido Zoledrônico/uso terapêutico
12.
Osteoporos Int ; 19(10): 1369-78, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18633664

RESUMO

The International Society for Clinical Densitometry (ISCD) conducts Position Development Conferences (PDCs) for the purpose of establishing standards and guidelines in the field of bone densitometry. Topics for consideration are selected according to clinical relevance, a perceived need for standardization, and the likelihood of achieving agreement. Questions regarding nomenclature, indications, acquisition, analysis, quality control, interpretation, and reporting of bone density tests for each topic area are assigned to task forces for a comprehensive review of the scientific literature. The findings of the review and recommendations are then presented to an international panel of experts at the PDC. The expert panel votes on potential Official Positions for appropriateness, necessity, quality of the evidence, strength of the recommendation, and applicability (worldwide or variable according to local requirements). Recommendations that are approved by the ISCD Board of Directors become Official Positions. The first Pediatric PDC was 20-21 June 2007 in Montreal, QC, Canada. The most recent Adult PDC was held 20-22 July 2007, in Lansdowne, VA, USA. This Special Report summarizes the methodology of the ISCD PDCs and presents selected Official Positions of general interest.


Assuntos
Absorciometria de Fóton/normas , Densidade Óssea , Osteoporose/diagnóstico , Absorciometria de Fóton/instrumentação , Absorciometria de Fóton/métodos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Fraturas Ósseas/etiologia , Fraturas Ósseas/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Seleção de Pacientes , Fatores de Risco , Adulto Jovem
13.
Cancer Res ; 52(18): 4948-53, 1992 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-1516051

RESUMO

The reactivity of a panel of antiganglioside monoclonal antibodies with a number of melanoma cell lines having different ganglioside composition profiles was studied. One cell line synthesized only GM3, one produced both GM3 and GD2, 2 had GM3 and GD3 as their major gangliosides, and 2 others synthesized approximately equal amounts of GM3, GM2, GD3, and GD2 gangliosides. Antibody reactivity with viable cells was analyzed by: (a) flow cytometry on suspension cells; and (b) mixed hemagglutination assays or immune adherence assays on monolayer cells in culture. GM3 was efficiently detected only in the cell line having GM3 as its sole ganglioside. In the other cell lines, GM3 was difficult to detect even in cells in which it made up a high proportion (up to 50%) of the total ganglioside content. GM2 was easily detectable only in JB-RH melanoma cells (which contain only GM3 and GM2). GD3 was the most reactive ganglioside in 2 cell lines and GD2 in 2 other lines. In general, the most complex ganglioside present in a cell was the one most accessible to antibody. The differential exposure at the cell surface of specific gangliosides may have implications for antibody-directed tumor detection and therapy and for cell-protein or cell-cell interactions that involve glycolipids.


Assuntos
Antígenos de Superfície/imunologia , Gangliosídeos/imunologia , Melanoma/imunologia , Lipídeos de Membrana/imunologia , Cromatografia em Camada Fina , Citometria de Fluxo , Humanos , Técnicas In Vitro , Melanoma/química , Células Tumorais Cultivadas
14.
Pediatr Obes ; 11(3): 210-20, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26132306

RESUMO

BACKGROUND: Evidence is lacking to recommend one diet over another when treating polycystic ovary syndrome (PCOS). OBJECTIVES: To obtain preliminary data, comparing the impact of a low-glycaemic load (LGL) vs. low-fat (LF) diet on biochemical hyperandrogenism in overweight and obese adolescents with PCOS. To ascertain feasibility of recruiting study participants, in partnership with an adolescent clinic, and implementing dietary interventions. METHODS: Randomized controlled trial of 19 overweight and obese adolescents with PCOS and not using hormonal contraceptives (HCs). Interventions comprised nutrition education, dietary counselling and cooking workshops to foster adherence to a LGL (45% carbohydrate, 35% fat, 20% protein) or LF (55% carbohydrate, 25% fat, 20% protein) diet over 6 months. Serum bioavailable testosterone was the primary outcome. RESULTS: Sixteen (LGL, n = 7; LF, n = 9) participants completed the study. Body fat percentage decreased (P < 0.05) in response to the interventions, with no difference between the LGL and LF groups (-1.2% vs. -2.2%; P = 0.16). Bioavailable testosterone did not change for either group (-0.4 vs. -1.8 ng dL(-1) ; P = 0.35). Regarding feasibility, recruiting adolescents posed a challenge, and use of HCs was a main reason for ineligibility. Participants attended 5.9 of 6 in-person visits and 2.6 of 3 cooking workshops, completed 4.9 of 6 telephone counselling calls, and reported high satisfaction with the diets and cooking workshops (≥8 on a 10-cm scale). CONCLUSIONS: Dietary interventions were beneficial for weight control but did not attenuate biochemical hyperandrogenism. Innovative strategies are needed to recruit adolescents for studies aimed at assessing independent effects of diet on features of PCOS.


Assuntos
Síndrome do Ovário Policístico/dietoterapia , Adolescente , Adulto , Composição Corporal , Culinária/métodos , Aconselhamento , Dieta , Dieta com Restrição de Gorduras , Feminino , Carga Glicêmica , Humanos , Resistência à Insulina , Obesidade/complicações , Obesidade/dietoterapia , Sobrepeso/complicações , Sobrepeso/dietoterapia , Educação de Pacientes como Assunto , Projetos Piloto
15.
J Bone Miner Res ; 14(1): 136-45, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9893076

RESUMO

Bone loss is a serious consequence of anorexia nervosa (AN). Subnormal levels of serum dehydroepiandrosterone (DHEA) are seen in patients with AN and may be causally linked to their low bone density. We hypothesized that oral DHEA would decrease markers of bone resorption (urinary N-telopeptides [NTx]), and increase markers of bone formation (serum bone-specific alkaline phosphatase and osteocalcin [OC]). Fifteen young women (age 15-22 years) with AN were enrolled in a 3-month, randomized, double-blinded trial of 50, 100, or 200 mg of daily micronized DHEA. Blood and urinary levels of adrenal and gonadal steroids and bone turnover markers were measured. No adverse clinical side effects of DHEA were noted, and a 50 mg daily dose restored physiologic hormonal levels. At 3 months, NTx levels had decreased significantly in both the 50 mg (p = 0.018) and the 200 mg (p = 0.016) subgroups. OC levels simultaneously increased within treatment groups over time (p = 0.002). Eight out of 15 (53%) subjects had at least one menstrual cycle while on therapy. Short-term DHEA was well-tolerated and appears to normalize bone turnover in young women with AN. Resumption of menses in over half of subjects suggests that DHEA therapy may also lead to estradiol levels sufficient to stimulate the endometrium in this group of patients.


Assuntos
Anorexia Nervosa/tratamento farmacológico , Remodelação Óssea/efeitos dos fármacos , Desidroepiandrosterona/uso terapêutico , Ciclo Menstrual/efeitos dos fármacos , Administração Oral , Adolescente , Adulto , Fosfatase Alcalina/metabolismo , Androgênios/metabolismo , Anorexia Nervosa/metabolismo , Biomarcadores , Desidroepiandrosterona/sangue , Suplementos Nutricionais , Esquema de Medicação , Estradiol/metabolismo , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Osteocalcina/sangue
16.
Cancer Immun ; 1: 4, 2001 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-12747765

RESUMO

The ability of the immune system to recognize structurally altered, amplified or aberrantly expressed proteins can be used to identify molecules of etiologic relevance to cancer and to define targets for cancer immunotherapy. In the current study, ninety-four distinct antigens reactive with serum IgG from breast cancer patients were identified by immunoscreening breast cancer-derived cDNA expression libraries (SEREX). A serological profile was generated for each antigen on the basis of reactivity with allogeneic sera from normal individuals and cancer patients, and mRNA expression profiles for coding sequences were assembled based upon the tissue distribution of expressed sequence tags, Northern blots and real-time RT-PCR. Forty antigens reacted exclusively with sera from cancer patients. These included well-characterized tumor antigens, e.g. MAGE-3, MAGE-6, NY-ESO-1, Her2neu and p53, as well as newly-defined breast cancer antigens, e.g. kinesin 2, TATA element modulatory factor 1, tumor protein D52 and MAGE D, and novel gene products, e.g. NY-BR-62, NY-BR-75, NY-BR-85, and NY-BR-96. With regard to expression profiles, two of the novel gene products, NY-BR-62 and NY-BR-85, were characterized by a high level of testicular mRNA expression, and were overexpressed in 60% and 90% of breast cancers, respectively. In addition, mRNA encoding tumor protein D52 was overexpressed in 60% of breast cancer specimens, while transcripts encoding SNT-1 signal adaptor protein were downregulated in 70% of these cases. This study adds to the growing list of breast cancer antigens defined by SEREX and to the ultimate objective of identifying the complete repertoire of immunogenic gene products in human cancer (the cancer immunome).


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Formação de Anticorpos/genética , Formação de Anticorpos/imunologia , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Neoplasias da Mama/sangue , DNA Complementar/genética , DNA Complementar/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Biblioteca Gênica , Humanos , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
17.
J Histochem Cytochem ; 39(12): 1603-10, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1682363

RESUMO

Monoclonal antibodies (MAb) C219 and JSB-1 have been used extensively in the analysis of P-glycoprotein expression in normal and malignant tissues. This study demonstrates that some commercial lots of these MAb, even those supplied as purified immunoglobulins, contain contaminating anti-A blood group antibodies. In both sources of reagent, the antibody was specific for a particular A structure, known as repetitive or Type 3 A. These observations may account for earlier studies showing polymorphic variation in P-glycoprotein expression in epithelial tissues and an apparent correlation with the A blood type of the donor. Such reactivity can be eliminated by absorption of anti-P-glycoprotein reagents with A erythrocytes. These data re-emphasize the importance of evaluating MAb samples for unsuspected contaminating antibodies.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Anticorpos Monoclonais/imunologia , Carboidratos/imunologia , Isoanticorpos/imunologia , Glicoproteínas de Membrana/imunologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Animais , Sequência de Carboidratos , Linhagem Celular , Cromatografia em Camada Fina , Eritrócitos/metabolismo , Tubas Uterinas/metabolismo , Feminino , Glicolipídeos/imunologia , Testes de Hemaglutinação , Humanos , Imuno-Histoquímica , Isoantígenos/imunologia , Dados de Sequência Molecular , Neoplasias Ovarianas/metabolismo , Ovário/metabolismo , Controle de Qualidade , Suínos
18.
Arch Pediatr Adolesc Med ; 149(12): 1336-9, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7489070

RESUMO

OBJECTIVES: To determine whether skin care practices with iodine-containing disinfectants are putting patients in the neonatal intensive care unit at risk for primary hypothyroidism. Cutaneous exposure to povidone-iodine antiseptic solutions may be a cause of primary hypothyroidism in neonates. DESIGN: Prospective pilot study. SETTING: Level III neonatal intensive care unit of a university-affiliated hospital. PARTICIPANTS: Sequential sample of 47 medial and surgical patients admitted to the neonatal intensive care unit who received cutaneous povidone-iodine applications in preparation for invasive or surgical procedures. METHODS: Seven to 10 days after iodine exposure, capillary blood samples were obtained on filter paper blots for thyroid function testing and urine samples were collected to determine quantitative iodine concentrations. A plasma creatinine level was determined for each subject. RESULTS: A total of 47 patients were enrolled. The gestational ages of subjects ranged from 26 to 41 weeks (mean, 33.6 weeks); the male-to-female ratio was 28:19; and the birth weights ranged from 0.7 to 5.1 kg(mean, 2.42 kg). The thyroxine level ranged from 20 to 187 nmol/L (1.6 to 14.6 micrograms/dL) (mean, 102 nmol/L [7.9 micrograms/dL];reference, > or = 90 nmol/L [> or = 7 micrograms/dL]; and the thyrotropin level ranged from 0.1 to 16.5 mU/L (mean, 6.4 mU/L; reference, < 20 mU/L). The mean uridine iodine concentration was 2798.0 micrograms/dL (reference, < 40 micrograms/dL), and the mean plasma creatinine level was 60 mumol/L (0.69 mg/dL) (reference, < or = 50 mumol/L [ < or = 0.6 mg/dL] for males and < or = 40 mumol/L [ < or = 0.5 mg/dL] for females). CONCLUSIONS: There was no documentation of primary hypothyroidism in our subjects despite elevated urine iodine levels. While it is still possible that patients who receive long-term iodine exposure in other settings (eg, cardiac catheterization) are at risk for primary hypothyroidism, our study suggests that the amount of iodine absorbed through routine neonatal intensive care unit procedures does not substantially alter thyroid function during the first 10 days of life. An important confounding variable is that seven patients were receiving dopamine hydrochloride infusions and four were receiving dexamethasone phosphate at the time of sample collection. We therefore cannot rule out the possibility that these medications masked a thyrotropin level elevation that would have occurred in a primary hypothyroid state. We discuss implications for the interpretation of the results of neonatal thyroid function tests.


Assuntos
Anti-Infecciosos Locais/efeitos adversos , Hipotireoidismo/induzido quimicamente , Povidona-Iodo/efeitos adversos , Higiene da Pele/efeitos adversos , Administração Cutânea , Fatores de Confusão Epidemiológicos , Feminino , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/urina , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Projetos Piloto , Estudos Prospectivos
19.
Chem Commun (Camb) ; (22): 2364-5, 2001 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-12240077

RESUMO

The activation energy for hydrogen abstraction from imidazolium-based ionic liquids is significantly higher than that observed in conventional solvents.

20.
Health Psychol ; 15(1): 56-60, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8788541

RESUMO

The effects of alcohol intoxication on mediators of condom use were examined in a laboratory-based experiment. Twenty men were randomly assigned to either an alcohol or a nonalcohol beverage administration condition. Participants in the experimental condition drank vodka and tonic to achieve a blood alcohol level of 0.08%, whereas controls drank tonic only. All participants then completed a battery of measures related to condom and AIDS-related knowledge, motivation to use condoms, and behavioral self-efficacy regarding condom use. Findings from this exploratory study, which should be considered preliminary because of the small sample size, indicated that participants who received alcohol tended to report more negative attitudes toward condoms and lower self-efficacy to initiate condom use than controls. AIDS knowledge, appraisal of social norms regarding condom use, and perceived risk of infection were unaffected by alcohol consumption.


Assuntos
Intoxicação Alcoólica/psicologia , Preservativos , Infecções por HIV/prevenção & controle , Assunção de Riscos , Comportamento Sexual , Adulto , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Motivação
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