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1.
Osteoporos Int ; 26(1): 35-47, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25377496

RESUMO

UNLABELLED: Although trans women before the start of hormonal therapy have a less bone and muscle mass compared with control men, their bone mass and geometry are preserved during the first 2 years of hormonal therapy, despite of substantial muscle loss, illustrating the major role of estrogen in the male skeleton. PURPOSE: The aim of this study is to examine the evolution of areal and volumetric bone density, geometry, and turnover in trans women undergoing sex steroid changes, during the first 2 years of hormonal therapy. METHODS: In a prospective observational study, we examined 49 trans women (male-to-female) before and after 1 and 2 years of cross-sex hormonal therapy (CSH) in comparison with 49 age-matched control men measuring grip strength (hand dynamometer), areal bone mineral density (aBMD), and total body fat and lean mass using dual X-ray absorptiometry (DXA), bone geometry and volumetric bone mineral density, regional fat, and muscle area at the forearm and calf using peripheral quantitative computed tomography. Standardized treatment regimens were used with oral estradiol valerate, 4 mg daily (or transdermal 17-ß estradiol 100 µg/24 h for patients >45 years old), both combined with oral cyproterone acetate 50 mg daily. RESULTS: Prior to CSH, trans women had lower aBMD at all measured sites (all p < 0.001), smaller cortical bone size (all p < 0.05), and lower muscle mass and strength and lean body mass (all p < 0.05) compared with control men. During CSH, muscle mass and strength decreased and all measures of fat mass increased (all p < 0.001). The aBMD increased at the femoral neck, radius, lumbar spine, and total body; cortical and trabecular bone remained stable and bone turnover markers decreased (all p < 0.05). CONCLUSIONS: Although trans women, before CSH, have a lower aBMD and cortical bone size compared with control men, their skeletal status is well preserved during CSH treatment, despite of substantial muscle loss.


Assuntos
Densidade Óssea/efeitos dos fármacos , Estradiol/farmacologia , Procedimentos de Readequação Sexual/métodos , Transexualidade/fisiopatologia , Absorciometria de Fóton/métodos , Adulto , Composição Corporal , Densidade Óssea/fisiologia , Remodelação Óssea/efeitos dos fármacos , Estudos de Casos e Controles , Feminino , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Força Muscular/efeitos dos fármacos , Músculo Esquelético/patologia , Estudos Prospectivos , Transexualidade/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue
2.
J Musculoskelet Neuronal Interact ; 14(1): 41-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24583539

RESUMO

OBJECTIVES: The purpose of this study was to investigate whether there is already an association of insulin resistance (IR) with muscle mass and -force/torque in an adult population and whether this relationship is the same in distal and proximal body parts. METHODS: 358 Healthy young men were divided into a more insulin sensitive (MIS) (n=89) and a less insulin sensitive (LIS) group (n=89), respectively using lower and upper quartiles of HOMA-IR index (Homeostasis Model Assessment of IR). Muscle force/torque and lean mass, were compared between the two groups. RESULTS: LIS subjects had higher absolute thigh lean mass, but not higher thigh muscle torque, resulting in a lower torque per kg muscle. In upper arm, lean mass was higher in LIS subjects, but also absolute muscle torque resulted higher. For handgrip force, the LIS and MIS group had similar results, despite a trend towards higher forearm lean mass in LIS subjects. Lean mass % of total lean mass is lower in LIS subjects in more distal body parts. CONCLUSIONS: Already in a young healthy population, IR seems to be associated with lower force/torque per muscle mass and lower lean mass % of total lean mass predominantly in more distal body parts.


Assuntos
Resistência à Insulina/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Composição Corporal/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Torque
3.
Eur J Appl Physiol ; 114(4): 751-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24390687

RESUMO

PURPOSE: The molecular factors targeted by androgens and estrogens on muscle mass are not fully understood. The current study aimed to explore gene and protein expression of Atrogin-1, MuRF1, and myostatin in an androgen deprivation-induced muscle atrophy model. METHODS: We examined the effects of Orx either with or without testosterone (T) or estradiol (E2) administration on Atrogin-1 gene expression, and MuRF1 and myostatin gene and protein expression. Measurements were made in soleus (SOL), extensor digitorum longus (EDL) and levator ani/bulbocavernosus (LA/BC) of male C57BL/6 mice. RESULTS: Thirty days of Orx resulted in a reduction in weight gain and muscle mass. These effects were prevented by T. In LA/BC, Atrogin-1 and MuRF1 mRNA was increased throughout 30 days of Orx, which was fully reversed by T and partially by E2 administration. In EDL and SOL, a less pronounced upregulation of both genes was only detectable at the early stages of Orx. Myostatin mRNA levels were downregulated in LA/BC and upregulated in EDL following Orx. T, but not E2, reversed these effects. No changes in protein levels of MuRF1 and myostatin were found in EDL at any time point following Orx. CONCLUSIONS: The atrophy in SOL and EDL in response to androgen deprivation, and its restoration by T, is accompanied by only minimal changes in atrogenes and myostatin gene expression. The marked differences in muscle atrophy and atrogene and myostatin mRNA between LA/BC and the locomotor muscles suggest that the murine LA/BC is not an optimal model to study Orx-induced muscle atrophy.


Assuntos
Estradiol/farmacologia , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Miostatina/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Testosterona/farmacologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Contração Muscular , Proteínas Musculares/genética , Força Muscular , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Miostatina/genética , Especificidade de Órgãos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Ligases SKP Culina F-Box/genética , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases/genética
4.
Eur J Endocrinol ; 172(2): 163-71, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25550352

RESUMO

PURPOSE: To assess the evolution of body composition and bone metabolism in trans men during the first year of cross-sex hormonal therapy. METHODS: In a prospective controlled study, we included 23 trans men (female-to-male trans persons) and 23 age-matched control women. In both groups, we examined grip strength (hand dynamometer), biochemical markers of bone turnover (C-terminal telopeptides of type 1 collagen (CTX) and procollagen 1 aminoterminal propeptide (P1NP)), total body fat and lean mass, and areal bone mineral density (aBMD) by dual-X-ray absorptiometry (DXA) and fat and muscle area at the forearm and calf, bone geometry, and volumetric bone mineral density (vBMD) by peripheral quantitative computed tomography (pQCT), before treatment and after 1 year of treatment with undecanoate (1000 mg i.m./12 weeks). RESULTS: Before hormonal treatment, trans men had similar bone and body composition compared with control women. Testosterone treatment induced in trans men a gain in muscle mass (+10.4%) and strength and loss of fat mass (-9.7%) (all P<0.001) and increased the levels of P1NP and CTX (both P<0.01). Areal and volumetric bone parameters remained largely unchanged apart from a small increase in trabecular vBMD at the distal radius and in BMD at the total hip in trans men (P=0.036 and P=0.001 respectively). None of these changes were observed in the control group. CONCLUSIONS: Short-term testosterone treatment in trans men increased muscle mass and bone turnover. The latter may rather reflect an anabolic effect of testosterone treatment rather than bone loss.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Testosterona/administração & dosagem , Pessoas Transgênero , Adolescente , Adulto , Composição Corporal/efeitos dos fármacos , Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular/efeitos dos fármacos , Força Muscular/fisiologia , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
5.
Bone ; 69: 39-46, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25220426

RESUMO

BACKGROUND: Little is known about the effects of adrenal steroids on skeletal maturation and bone mass acquisition in healthy prepubertal boys. OBJECTIVE: To study whether adrenal-derived steroids within the physiological range are associated with skeletal maturation, areal and volumetric bone mineral density (aBMD and vBMD) and bone geometry in healthy prepubertal and early pubertal boys. METHODS: 98 healthy prepubertal and early pubertal boys (aged 6-14 y) were studied cross-sectionally. Androstenedione (A) and estrone (E1) were determined by liquid chromatography tandem mass spectrometry and DHEAS was determined by immunoassay. Whole body and lumbar spine aBMD and bone area were determined by dual-energy X-ray absorptiometry. Trabecular (distal site) and cortical (proximal site) vBMD and bone geometry were assessed at the non-dominant forearm and leg using peripheral QCT. Skeletal age was determined by X-ray of the left hand. RESULTS: Adrenal-derived steroids (DHEAS, A and E1) are positively associated with bone age in prepubertal and early pubertal children, independently of age. There are no associations between the adrenal-derived steroids and the studied parameters of bone size (lumbar spine and whole body bone area, trabecular or cortical area at the radius or tibia, periosteal circumference and cortical thickness at the radius or tibia) or BMD (aBMD or vBMD). CONCLUSION: In healthy prepubertal and early pubertal boys, serum adrenal-derived steroid levels, are associated with skeletal maturation, independently of age, but not with bone size or (v)BMD. Our data suggest that adrenal derived steroids are not implicated in the accretion of bone mass before puberty in boys.


Assuntos
Androstenodiona/sangue , Desenvolvimento Ósseo/fisiologia , Osso e Ossos/diagnóstico por imagem , Sulfato de Desidroepiandrosterona/sangue , Estrona/sangue , Absorciometria de Fóton , Adolescente , Densidade Óssea , Criança , Cromatografia Líquida de Alta Pressão , Estudos Transversais , Humanos , Imunoensaio , Masculino , Puberdade , Tomografia Computadorizada por Raios X
6.
J Clin Endocrinol Metab ; 99(7): E1272-82, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24670081

RESUMO

BACKGROUND: Although both testosterone (T) and estradiol (E2) are considered essential in the regulation of the male skeleton, there are few data concerning the relative contribution of T and E2 on bone mineral density (BMD), bone geometry, and bone maturation in healthy boys. OBJECTIVE: The objective of the study was to analyze the relationship between T and E2 and BMD, bone geometry, skeletal maturation, and body composition. METHODS: This is a cross-sectional study in 199 healthy boys (aged 6-19 y). T and E2 were determined by liquid chromatography tandem mass spectrometry. Whole-body and lumbar areal bone mineral density (aBMD) and bone area, lean mass, and fat mass were determined by dual-energy X-ray absorptiometry. Trabecular (distal site) and cortical (proximal site) volumetric BMD (vBMD) and bone geometry were assessed at the nondominant forearm and leg using peripheral quantitative computed tomography. Skeletal age was determined by an X-ray of the left hand. RESULTS: T was positively associated with lean mass (P < .001), lumbar and whole-body bone area (P < .001), trabecular and cortical area (P < .01), and periosteal circumference (P < .01) at the radius. E2 was positively associated with lumbar and whole-body aBMD (P < .001), trabecular vBMD at the radius and tibia (P < .01), and cortical thickness at the radius (P < .05). E2 was an independent negative predictor of the endosteal circumference (P < .01). Moreover, E2 was positively associated with bone age advancement (P < .001). CONCLUSION: Circulating E2 is positively associated with bone maturation and aBMD and vBMD and negatively with endosteal circumference in healthy boys, whereas T is a determinant of lean mass and bone size. These findings underscore the important role of E2 in skeletal development in boys.


Assuntos
Composição Corporal , Densidade Óssea , Desenvolvimento Ósseo , Osso e Ossos/anatomia & histologia , Hormônios Esteroides Gonadais/sangue , Adolescente , Desenvolvimento do Adolescente , Criança , Estudos Transversais , Saúde , Humanos , Masculino , Tamanho do Órgão , Adulto Jovem
7.
J Clin Endocrinol Metab ; 99(8): 2977-85, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24796931

RESUMO

BACKGROUND: Childhood obesity is associated with an accelerated skeletal maturation. However, data concerning pubertal development and sex steroid levels in obese adolescents are scarce and contrasting. OBJECTIVES: To study sex steroids in relation to sexual and skeletal maturation and to serum prostate specific antigen (PSA), as a marker of androgen activity, in obese boys from early to late adolescence. METHODS: Ninety obese boys (aged 10-19 y) at the start of a residential obesity treatment program and 90 age-matched controls were studied cross-sectionally. Pubertal status was assessed according to the Tanner method. Skeletal age was determined by an x-ray of the left hand. Morning concentrations of total testosterone (TT) and estradiol (E2) were measured by liquid chromatography-tandem mass spectrometry, free T (FT) was measured by equilibrium dialysis, and LH, FSH, SHBG, and PSA were measured by immunoassays. RESULTS: Genital staging was comparable between the obese and nonobese groups, whereas skeletal bone advancement (mean, 1 y) was present in early and midadolescence in the obese males. Although both median SHBG and TT concentrations were significantly (P < .001) lower in obese subjects during mid and late puberty, median FT, LH, FSH, and PSA levels were comparable to those of controls. In contrast, serum E2 concentrations were significantly (P < .001) higher in the obese group at all pubertal stages. CONCLUSION: Obese boys have lower circulating SHBG and TT, but similar FT concentrations during mid and late puberty in parallel with a normal pubertal progression and serum PSA levels. Our data indicate that in obese boys, serum FT concentration is a better marker of androgen activity than TT. On the other hand, skeletal maturation and E2 were increased from the beginning of puberty, suggesting a significant contribution of hyperestrogenemia in the advancement of skeletal maturation in obese boys.


Assuntos
Desenvolvimento Ósseo , Hormônios Esteroides Gonadais/sangue , Obesidade Infantil/sangue , Obesidade Infantil/fisiopatologia , Maturidade Sexual , Adolescente , Desenvolvimento do Adolescente , Determinação da Idade pelo Esqueleto , Estudos de Casos e Controles , Criança , Estudos Transversais , Humanos , Masculino , Tamanho do Órgão , Testículo/crescimento & desenvolvimento
8.
Eur J Endocrinol ; 168(4): 615-20, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23389587

RESUMO

OBJECTIVE: Sclerostin inhibits osteoblast differentiation and bone formation. If aberrant sclerostin action is involved in less efficient bone acquisition in men with idiopathic low bone mass, this might be reflected in higher serum sclerostin levels. METHODS: In 116 men with idiopathic osteoporosis (≤65 years old), 40 of their sons and healthy controls, areal bone parameters were measured using dual-energy X-ray absorptiometry, and volumetric and geometric bone parameters were measured using peripheral quantitative computed tomography. Serum analytes were measured using immunoassays and estradiol (E2) levels using liquid chromatography-tandem mass spectrometry. RESULTS: Men with idiopathic low bone mass had lower levels of sclerostin than the controls (0.54±0.17 vs 0.66±0.23 ng/ml; P<0.001). In both groups, sclerostin levels were strongly associated with age; when adjusting for age, no associations with anthropometrics were observed (P>0.14). In multivariate analyses, sclerostin levels displayed a positive association with whole-body bone mineral content (BMC) and areal BMD (aBMD), as well as with trabecular and cortical volumetric bone mineral density (vBMD) at the tibia in the probands. No clear associations were observed in the control group, neither were sclerostin levels associated with BMC at the radius or lumbar spine (all P>0.11). Testosterone, but not E2, was inversely related to sclerostin levels in the probands. No difference in sclerostin levels was found in their sons when compared with their controls. CONCLUSION: Lower rather than higher serum sclerostin levels in the probands with idiopathic low bone mass suggest that aberrant sclerostin secretion is not involved in the pathogenesis of low bone mass in these subjects.


Assuntos
Biomarcadores/sangue , Proteínas Morfogenéticas Ósseas/metabolismo , Osteoporose/sangue , Osteoporose/diagnóstico , Absorciometria de Fóton/métodos , Proteínas Adaptadoras de Transdução de Sinal , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Bone ; 54(1): 92-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23369987

RESUMO

OBJECTIVE: Cross-sex hormonal therapy and sex reassignment surgery (including gonadectomy) in transsexual persons has an impact on body composition and bone mass and size. However, it is not clear whether baseline differences in bone and body composition between transsexual persons and controls before cross-sex hormonal therapy play a role. DESIGN: A cross-sectional study with 25 male-to-female transsexual persons (transsexual women) before cross-gender sex steroid exposure (median age 30 years) in comparison with 25 age-matched control men and a male reference population of 941 men. MAIN OUTCOME MEASURES: Areal and volumetric bone parameters using respectively dual energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT), body composition (DXA), grip strength (hand dynamometer), Baecke physical activity questionnaire, serum testosterone and 25-OH vitamin D. RESULTS: Transsexual women before cross-sex hormonal therapy presented with less muscle mass (p≤0.001) and strength (p≤0.05) and a higher prevalence of osteoporosis (16%) with a lower aBMD at the hip, femoral neck, total body (all p<0.001) and lumbar spine (p=0.064) compared with control men. A thinner radial cortex (p≤0.01) and lower cortical area at the radius and tibia (both p<0.05) was found in transsexual women vs. control men. Serum testosterone was comparable in all 3 groups, but 25-OH vitamin D was lower in transsexual women (p≤0.001). CONCLUSIONS: Transsexual women before the start of hormonal therapy appear to have lower muscle mass and strength and lower bone mass compared with control men. These baseline differences in bone mass might be related to a less active lifestyle.


Assuntos
Osso e Ossos/patologia , Gônadas/cirurgia , Terapia de Reposição Hormonal/estatística & dados numéricos , Pessoas Transgênero/estatística & dados numéricos , Absorciometria de Fóton , Adulto , Bélgica/epidemiologia , Composição Corporal , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/fisiopatologia , Feminino , Humanos , Extremidade Inferior/diagnóstico por imagem , Extremidade Inferior/patologia , Extremidade Inferior/fisiopatologia , Masculino , Atividade Motora , Tamanho do Órgão , Prevalência , Tomografia Computadorizada por Raios X , Extremidade Superior/diagnóstico por imagem , Extremidade Superior/patologia , Extremidade Superior/fisiopatologia
10.
Eur J Endocrinol ; 169(4): 471-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23904280

RESUMO

OBJECTIVE: This study evaluated the short- and long-term cardiovascular- and cancer-related morbidities during cross-sex hormone therapy in a large sample of trans persons. SUBJECTS AND METHODS: A specialist center cross-sectional study compared 214 trans women (male-to-female transsexual persons) and 138 trans men (female-to-male trans persons) with an age- and gender-matched control population (1-3 matching). The participants were on cross-sex hormone therapy for an average of 7.4 years. We assessed physical health and possible treatment-related adverse events using questionnaires. RESULTS: Five percent of trans women experienced venous thrombosis and/or pulmonary embolism during hormone therapy. Five of these adverse events occurred during the first year of treatment, while another three occurred during sex reassignment surgery. Trans women experienced more myocardial infarctions than the control women (P=0.001), but a similar proportion compared with control men. The prevalence of cerebrovascular disease (CVD) was higher in trans women than in the control men (P=0.03). The rates of myocardial infarction and CVD in trans men were similar to the control male and female subjects. The prevalence of type 2 diabetes was higher in both trans men and women than in their respective controls, whereas the rates of cancer were similar compared with the control men and women. CONCLUSION: Morbidity rate during cross-sex hormone therapy was relatively low, especially in trans men. We observed a higher prevalence of venous thrombosis, myocardial infarction, CVD, and type 2 diabetes in trans women than in the control population. Morbidity rates in trans men and controls were similar, with the exception of the increased prevalence of type 2 diabetes.


Assuntos
Doenças Cardiovasculares/epidemiologia , Neoplasias/epidemiologia , Pessoas Transgênero/estatística & dados numéricos , Adulto , Estudos de Casos e Controles , Transtornos Cerebrovasculares/epidemiologia , Estudos Transversais , Feminino , Seguimentos , Hormônios Esteroides Gonadais/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Infarto do Miocárdio/epidemiologia , Prevalência , Embolia Pulmonar/epidemiologia , Fatores de Risco , Trombose Venosa/epidemiologia
11.
J Clin Endocrinol Metab ; 98(7): 3019-28, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23666962

RESUMO

CONTEXT: Controversy exists on the effect of obesity on bone development during puberty. OBJECTIVE: Our objective was to determine differences in volumetric bone mineral density (vBMD) and bone geometry in male obese adolescents (ObAs) in overlap with changes in bone maturation, muscle mass and force development, and circulating sex steroids and IGF-I. We hypothesized that changes in bone parameters are more evident at the weight-bearing site and that changes in serum estradiol are most prominent. DESIGN, SETTING, AND PARTICIPANTS: We recruited 51 male ObAs (10-19 years) at the entry of a residential weight-loss program and 51 healthy age-matched and 51 bone-age-matched controls. MAIN OUTCOME MEASURES: vBMD and geometric bone parameters, as well as muscle and fat area were studied at the forearm and lower leg by peripheral quantitative computed tomography. Muscle force was studied by jumping mechanography. RESULTS: In addition to an advanced bone maturation, differences in trabecular bone parameters (higher vBMD and larger trabecular area) and cortical bone geometry (larger cortical area and periosteal and endosteal circumference) were observed in ObAs both at the radius and tibia at different pubertal stages. After matching for bone age, all differences at the tibia, but only the difference in trabecular vBMD at the radius, remained significant. Larger muscle area and higher maximal force were found in ObAs compared with controls, as well as higher circulating free estrogen, but similar free testosterone and IGF-I levels. CONCLUSIONS: ObAs have larger and stronger bones at both the forearm and lower leg. The observed differences in bone parameters can be explained by a combination of advanced bone maturation, higher estrogen exposure, and greater mechanical loading resulting from a higher muscle mass and strength.


Assuntos
Desenvolvimento do Adolescente , Desenvolvimento Ósseo , Desenvolvimento Infantil , Obesidade/patologia , Rádio (Anatomia)/patologia , Tíbia/patologia , Adolescente , Adulto , Índice de Massa Corporal , Densidade Óssea , Criança , Estradiol/sangue , Antebraço , Humanos , Perna (Membro) , Masculino , Desenvolvimento Muscular , Força Muscular , Obesidade/sangue , Obesidade/fisiopatologia , Radiografia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/fisiopatologia , Tíbia/diagnóstico por imagem , Tíbia/fisiopatologia , Suporte de Carga , Adulto Jovem
12.
J Clin Endocrinol Metab ; 97(7): 2503-11, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22564669

RESUMO

CONTEXT: Female-to-male transsexual persons (transsexual men) undergo extreme hormonal changes due to ovariectomy and testosterone substitution, allowing studies on sex steroid effects on bone geometry and physiology in the adult. OBJECTIVE: The objective of the study was to examine the effects of cross-gender sex steroid exposure on volumetric bone parameters in transsexual men. DESIGN: This was a cross-sectional study. SETTING: Participants were recruited from the Center for Sexology and Gender Problems at the Ghent University Hospital (Ghent, Belgium). PARTICIPANTS: Fifty transsexual men after sex reassignment surgery with 50 age-matched control women and an additional 16 transsexual men before testosterone substitution and sex reassignment surgery with 16 control women participated in the study. MAIN OUTCOME MEASURES: The main outcome measures were areal and volumetric bone parameters using dual-energy X-ray absorptiometry and peripheral quantitative computed tomography, body composition (dual-energy X-ray absorptiometry), sex steroids, markers of bone turnover and grip strength. RESULTS: Before hormonal treatment, transsexual men had similar body composition and bone geometry as female controls. The transsexual men on long-term testosterone therapy, however, demonstrated a higher lean body mass and muscle mass and a greater grip strength as well as a lower body and subcutaneous fat mass and a larger waist and smaller hip circumference compared with female controls (all P < 0.001). We observed a larger radial cortical bone size (P < 0.001) and lower cortical volumetric bone mineral density at the radius and tibia (P < 0.05) in transsexual men on testosterone therapy. CONCLUSIONS: Transsexual men on testosterone substitution therapy present with a different body composition with more muscle mass and strength and less fat mass as well as an altered bone geometry with larger bones compared with female controls.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Osso e Ossos/anatomia & histologia , Terapia de Reposição Hormonal , Procedimentos de Readequação Sexual , Transexualidade/fisiopatologia , Transexualidade/terapia , Absorciometria de Fóton , Adulto , Desenvolvimento Ósseo/fisiologia , Osso e Ossos/diagnóstico por imagem , Estudos de Casos e Controles , Estudos Transversais , Feminino , Terapia de Reposição Hormonal/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Procedimentos de Readequação Sexual/métodos , Fatores de Tempo , Transexualidade/diagnóstico por imagem , Transexualidade/metabolismo , Adulto Jovem
13.
Eur J Endocrinol ; 159(4): 459-68, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18593825

RESUMO

OBJECTIVE: This study was designed to assess longitudinal changes in serum testosterone levels, explore relationships with aging, genetic-, health-, and lifestyle-related factors, and investigate predictors of changes in healthy elderly men. DESIGN: Population-based, longitudinal, 4-year observational study in 221 community-dwelling men aged 71-86 years at baseline. METHODS: Hormone levels assessed by immunoassay, anthropometry, questionnaires on general health, and genetic polymorphisms. Predictors of changes in testosterone levels explored using linear mixed-effects modeling for longitudinal analyses. RESULTS: Total testosterone (TT), free testosterone, and bioavailable testosterone (BioT) levels decreased with aging, decreases in BioT being most marked. No changes in sex hormone-binding globulin (SHBG) or estradiol (E(2)), while LH and FSH levels increased during follow-up. Subjects who gained weight displayed a greater decline in TT levels, mainly due to decreasing SHBG levels. However, baseline body composition was not predictive of subsequent changes in testosterone levels. Baseline E(2) (P=0.023 to 0.004), LH (P=0.046 to 0.005), and FSH (P<0.002) levels were independently positively associated with a faster decline in testosterone fractions, although only FSH remained significant when adjusting for baseline testosterone (P=0.041-0.035). Carriers of a 'TA' haplotype of the estrogen receptor alpha gene (ER alpha) PvuII and XbaI polymorphisms displayed a slower decline of TT and BioT (P=0.041-0.007). CONCLUSIONS: In elderly men with already low serum testosterone levels, a further decline was observed, independent of baseline age. The identification of FSH levels as a predictor of this decline appears to reflect the testicular mechanisms of aging-related changes in testosterone production, whereas associations with E(2) and ER alpha polymorphisms are suggestive of estrogen-related processes, possibly related to changes in the neuroendocrine regulation of testosterone production.


Assuntos
Envelhecimento/metabolismo , Testosterona/sangue , Testosterona/deficiência , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Aromatase/genética , Composição Corporal , Estradiol/sangue , Receptor alfa de Estrogênio/genética , Hormônio Foliculoestimulante/sangue , Humanos , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Estilo de Vida , Estudos Longitudinais , Hormônio Luteinizante/sangue , Masculino , Saúde do Homem , Polimorfismo Genético , Valor Preditivo dos Testes , Características de Residência , Globulina de Ligação a Hormônio Sexual/metabolismo
14.
Clin Sci (Lond) ; 94(1): 57-63, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9505867

RESUMO

1. Chronic low blood pressure has been associated with fatigue and low mood. However, in the chronic fatigue syndrome (CFS) the blood pressure (BP) and heart rate profile and their variabilities have not been characterized as yet. 2. We performed office and 24 h ambulatory BP recordings in 38 subjects (age, 34.8 +/- 8.0 years) who fulfilled the Holmes criteria for CFS and in 38 healthy control subjects (age 35.6 +/- 10.5 years), as well as short-term beat-to-beat BP and RR-interval recordings for 10 min in supine and standing position, and calculated spectral indices. 3. In CFS office (123 +/- 19/70 +/- 12 mmHg) as well as 24-h, day- and night-time blood pressure values (116 +/- 11.1/71 +/- 11.1, 121 +/- 9.2/77 +/- 8.0 and 110 +/- 10.5/65 +/- 9.2 mmHg respectively) were within reference limits. 4. Heart rate was consistently higher (P < 0.01) in CFS patients, based on both office (77 +/- 12 compared with 68 +/- 12 beats min-1) and 24 h ambulatory recordings (77 +/- 12 compared with 67 +/- 15 beats min-1). 5. In supine position, spectral indices of BP variability (total, low-frequency and high-frequency variances) were all significantly (P < 0.01) lower in CFS. In standing position the differences disappeared. Analysis of RR-interval variability could not detect major alterations in autonomic function in CFS.


Assuntos
Pressão Sanguínea/fisiologia , Síndrome de Fadiga Crônica/fisiopatologia , Síndrome de Fadiga Crônica/psicologia , Frequência Cardíaca/fisiologia , Estresse Psicológico , Adulto , Análise de Variância , Eletrocardiografia , Eletrocardiografia Ambulatorial , Feminino , Humanos , Masculino , Postura/fisiologia , Processamento de Sinais Assistido por Computador , Fatores de Tempo
15.
Clin Chem ; 46(12): 2008-13, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11106339

RESUMO

BACKGROUND: We present the case of an 80-year-old woman who was admitted to hospital with an intermittent volvulus of the right colon. A total colectomy was performed. Initially, serum amylase and lipase increased concordantly, but after a few weeks amylase normalized (85 U/L), whereas lipase increased to 3764 U/L. This discrepancy and persistence of hyperlipasemia suggested a macromolecular form of lipase. METHODS: The nature of the macromolecular complex was studied using high-pressure liquid gel-permeation chromatography, affinity chromatography, (immuno)electrophoresis, and immunodiffusion. RESULTS: Gel-permeation chromatography revealed a macrolipase, with a molecular mass >900 kDa, that contributed up to 56% of total serum lipase activity. Butanol extraction of the specimen did not alter the elution profile. The thermostabilities of pancreatic lipase and the macroform were similar, whereas activation energy (E:(a)) was lower in the macromolecular lipase (28 +/- 4 kJ. mol(-1). K(-1) vs 48 +/- 7 kJ. mol(-1). K(-1) (P: = 0.02). Agarose electrophoresis showed a broad band of lipase activity at the application site. Protein A-Sepharose affinity gel chromatography excluded IgG-linked lipase. Agarose electrophoresis and immunofixation excluded linkage to other immunoglobulins. Radial immunodiffusion did not show lipase activity in the immunoglobulin precipitation bands. Radial immunodiffusion with alpha(2)-macroglobulin (alpha(2)-MG) antibodies showed a diffuse spot of lipase activity within the precipitation band, suggesting a macromolecular association between lipase and alpha(2)-MG. Affinity gel chromatography against alpha(2)-MG showed lipase activity in the alpha(2)-MG-bound fractions. CONCLUSION: This is the first report of a macrolipase in which an association between alpha(2)-MG and lipase is described.


Assuntos
Lipase/sangue , alfa-Macroglobulinas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Amilases/sangue , Amilases/química , Cromatografia em Gel , Colectomia , Colo , Eletroforese em Gel de Ágar , Estabilidade Enzimática , Feminino , Humanos , Imunoensaio , Obstrução Intestinal/enzimologia , Obstrução Intestinal/cirurgia , Lipase/química , Substâncias Macromoleculares , alfa-Macroglobulinas/química
16.
Eur Heart J ; 19(9): 1371-6, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9792263

RESUMO

AIMS: The purpose of this study was to examine, in chronically treated heart failure patients vs control subjects, the influence of neurohumoral activation and aldosterone escape on arterial elastic behaviour, assessed by non-invasive mathematical lumped-parameter modelling of the compliance of the arterial system. METHODS AND RESULTS: Radial arterial pulse waves were recorded non-invasively for 30 s with an arterial tonometer sensor array in 13 chronic heart failure patients (mean age, 59 +/- 2.5 years) in New York Heart Association class II. The patients had been taking digoxin, furosemide, captopril and aspirin for more than 3 months. Thirteen healthy subjects (mean age, 50 +/- 4.0 years) acted as controls. Compliance of the proximal (aorta and major branches, C1) and distal parts (C2) of the circulation were derived from a third order four-element modified Windkessel model which can reproduce arterial pressure waveforms, including both exponential and oscillatory sections. Active renin, angiotensin II and aldosterone levels were determined on venous blood samples in the supine position and after 30 min active standing. There was decreased proximal (C1, 1.51 +/- 0.11 ml x mmHg(-1), P<0.01) and distal (C2, 0.050 +/- 0.011 ml x mmHg(-1)) arterial compliance in the chronic heart failure patients vs controls (C1, 1.71 +/- 0.16 ml x mmHg(-1); C2, 0.054 +/- 0.006 ml x mmHg(-1)). The chronic heart failure patients were characterized by an aldosterone escape phenomenon which was inversely correlated with the proximal arterial compliance in both supine (r= - 0.795, P=0.002) and standing (r= - 0.628, P=0.029) positions. CONCLUSIONS: In chronically treated heart failure patients with full angiotensin-converting enzyme-inhibition and diuretics, there is decreased compliance of the aorta and its major branches, which is inversely correlated with the aldosterone escape phenomenon.


Assuntos
Aldosterona/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Aorta Torácica/fisiologia , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Resistência Vascular/fisiologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Aorta Torácica/efeitos dos fármacos , Doença Crônica , Complacência (Medida de Distensibilidade)/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Sistema Renina-Angiotensina/fisiologia , Estatísticas não Paramétricas , Resistência Vascular/efeitos dos fármacos
17.
Clin Chem ; 47(3): 556-60, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11238311

RESUMO

BACKGROUND: Recently, the UF-100 (Sysmex Corporation) flow cytometer was developed to automate urinalysis. We evaluated the use of flow cytometry in the analysis of cerebrospinal fluid (CSF). METHODS: UF-100 data were correlated with microscopy and biochemical data for 256 CSF samples. Microbiological analysis was performed in 144 suspected cases of meningitis. RESULTS: Good agreement was obtained between UF-100 and microscopy data for erythrocytes (r = 0.919) and leukocytes (r = 0.886). In some cases, however, incorrect classification of lymphocytes by the UF-100 led to underestimation of the leukocyte count. UF-100 bacterial count positively correlated (P < 0.001) with UF-100 leukocyte count (r = 0.666), CSF total protein (r = 0.754), and CSF lactate concentrations (r = 0.641), and negatively correlated with CSF glucose concentration (r = -0.405; P < 0.001). UF-100 bacterial counts were unreliable in hemorrhagic samples and in samples collected by ventricular drainage where interference by blood platelets and cell debris was observed. Another major problem was the UF-100 "bacterial" background signal in sterile CSF samples. Cryptococcus neoformans yeast cells and cholesterol crystals in craniopharyngioma were detected by the flow cytometer. CONCLUSIONS: Flow cytometry of CSF with the UF-100 offers a rapid and reliable leukocytes and erythrocyte count. Additional settings offered by the instrument may be useful in the diagnosis of neurological disorders.


Assuntos
Líquido Cefalorraquidiano/citologia , Autoanálise , Bactérias/citologia , Líquido Cefalorraquidiano/microbiologia , Contagem de Eritrócitos/métodos , Feminino , Citometria de Fluxo/métodos , Humanos , Recém-Nascido , Contagem de Leucócitos/métodos , Masculino , Leveduras/citologia
18.
Clin Chem ; 46(10): 1619-25, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11017940

RESUMO

BACKGROUND: Human iron status is influenced by environmental and genetic factors. We hypothesized that the genetic polymorphism of haptoglobin (Hp), a hemoglobin-binding plasma protein, could affect iron status. METHODS: Reference values of serum iron status markers were compared according to Hp phenotypes (Hp 1-1, Hp 2-1, Hp 2-2; determined by starch gel electrophoresis) in 717 healthy adults. Iron storage was investigated in peripheral blood monocyte-macrophages by measuring cytosolic L- and H-ferritins and by in vitro uptake of radiolabeled ((125)I) hemoglobin-haptoglobin complexes. RESULTS: In males but not in females, the Hp 2-2 phenotype was associated with higher serum iron (P <0.05), transferrin saturation (P <0.05), and ferritin (P <0.01) concentrations than Hp 1-1 and 2-1, whereas soluble transferrin receptor concentrations were lower (P <0.05). Moreover, serum ferritin correlated with monocyte L-ferritin content (r = 0.699), which was also highest in the male Hp 2-2 subgroup (P <0.01). In vitro, monocyte-macrophages took up a small fraction of (125)I-labeled hemoglobin complexed to Hp 2-2 but not to Hp 1-1 or 2-1. CONCLUSIONS: The Hp 2-2 phenotype affects serum iron status markers in healthy males and is associated with higher L-ferritin concentrations in monocyte-macrophages because of a yet undescribed iron delocalization pathway, selectively occurring in Hp 2-2 subjects.


Assuntos
Haptoglobinas/genética , Ferro/metabolismo , Adolescente , Adulto , Biomarcadores/sangue , Citosol/química , Eletroforese em Gel de Amido , Feminino , Ferritinas/análise , Hemoglobinas/metabolismo , Humanos , Técnicas In Vitro , Macrófagos/química , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/química , Monócitos/metabolismo , Fenótipo , Polimorfismo Genético , Receptores da Transferrina/análise , Valores de Referência , Transferrina/análise
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