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1.
Eur J Clin Nutr ; 71(3): 365-371, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27782114

RESUMO

BACKGROUND/OBJECTIVES: Normal-weight women frequently restrict their caloric intake and exercise, but little is known about the effects on body weight, body composition and metabolic adaptations in this population. SUBJECTS/METHODS: We conducted a secondary analysis of data from a randomized controlled trial in sedentary normal-weight women. Women were assigned to a severe energy deficit (SEV: -1062±80 kcal per day; n=9), a moderate energy deficit (MOD: -633±71 kcal per day; n=7) or energy balance (BAL; n=9) while exercising five times per week for 3 months. Outcome variables included changes in body weight, body composition, resting metabolic rate (RMR) and metabolic hormones associated with energy conservation. RESULTS: Weight loss occurred in SEV (-3.7±0.9 kg, P<0.001) and MOD (-2.7±0.8 kg; P=0.003), but weight loss was significantly less than predicted (SEV: -11.1±1.0 kg; MOD: -6.5±1.1 kg; both P<0.001 vs actual). Fat mass declined in SEV (P<0.001) and MOD (P=0.006), whereas fat-free mass remained unchanged in all groups (P>0.33). RMR decreased by -6±2% in MOD (P=0.020). In SEV, RMR did not change on a group level (P=0.66), but participants whose RMR declined lost more weight (P=0.020) and had a higher baseline RMR (P=0.026) than those whose RMR did not decrease. Characteristic changes in leptin (P=0.003), tri-iodothyronine (P=0.013), insulin-like growth factor-1 (P=0.016) and ghrelin (P=0.049) occurred only in SEV. The energy deficit and adaptive changes in RMR explained 54% of the observed weight loss. CONCLUSIONS: In normal-weight women, caloric restriction and exercise resulted in less-than-predicted weight loss. In contrast to previous literature, weight loss consisted almost exclusively of fat mass, whereas fat-free mass was preserved.


Assuntos
Metabolismo Basal , Restrição Calórica , Exercício Físico , Redução de Peso , Adolescente , Adulto , Composição Corporal , Índice de Massa Corporal , Dieta , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Feminino , Humanos , Cooperação do Paciente , Estudos Retrospectivos , Adulto Jovem
2.
Osteoporos Int ; 28(4): 1365-1376, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28032184

RESUMO

Many female athletes are energy and/or estrogen deficient, but the independent effects on bone health have not been isolated. Energy deficiency was detrimental at the tibia while estrogen deficiency was detrimental at the radius. Nutrition must be considered alongside menstrual recovery when addressing compromised bone health in female athletes. INTRODUCTION: The purpose of this study was to describe volumetric bone mineral density (vBMD), bone geometry, and estimated bone strength in exercising women (n = 60) grouped according to energy status (energy replete (EnR: n = 30) vs. energy deficient (EnD: n = 30)) and estrogen status (estrogen replete (E2R: n = 33) vs. estrogen deficient (E2D: n = 27)), resulting in four distinct groups: EnR + E2R (n = 17), EnR + E2D (n = 13), EnD + E2R (n = 16), EnD + E2D (n = 14). METHODS: Energy status was determined using the ratio of measured to predicted resting energy expenditure (mREE/pREE). Estrogen status was based on self-reported menstrual status confirmed by daily evaluation of urinary estrone-1-glucoronide (E1G), pregnanediol glucuronide (PdG), and luteinizing hormone (LH). Eumenorrheic women were considered E2R, amenorrheic women were E2D, and oligomenorrheic women were categorized based on history of menses in the past year. Bone was assessed using peripheral quantitative computed tomography (pQCT). RESULTS: EnD women exhibited lower total vBMD, trabecular vBMD, cortical area, and BSI at the distal tibia and lower total vBMD, smaller cortical area and cortical thickness, and larger endosteal circumference at the proximal tibia compared to EnR women (p < 0.042). E2D women had lower total and cortical vBMD, larger total and trabecular area, and lower BSI at the distal radius and lower cortical vBMD at the proximal radius compared to E2R women (p < 0.023). Energy and estrogen interacted to affect total and trabecular area at the distal tibia (p < 0.021). CONCLUSIONS: Efforts to correct energy deficiency, which in turn may promote reproductive health, are warranted in order to address the unique contributions of energy status versus estrogen status to bone health.


Assuntos
Densidade Óssea/fisiologia , Metabolismo Energético/fisiologia , Estrogênios/deficiência , Exercício Físico/fisiologia , Adolescente , Adulto , Antropometria/métodos , Estudos Transversais , Feminino , Humanos , Ciclo Menstrual/fisiologia , Rádio (Anatomia)/fisiologia , Tíbia/fisiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
3.
Osteoporos Int ; 27(9): 2755-2764, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27129456

RESUMO

UNLABELLED: Energy restriction causes bone loss, increasing stress fracture risk. The impact of exercise during energy restriction on bone and endocrine factors is examined. Exercise with energy restriction did not influence endocrine factors, but did mitigate some bone loss seen with energy restriction in sedentary rats. INTRODUCTION: Chronic dietary energy restriction (ER) leads to bone loss and increased fracture risk. Strictly controlled trials of long-term ER with and without vigorous exercise are required to determine whether exercise loading can counterbalance ER-induced bone loss. The aim of this current project is to elucidate the impact of exercise and ER on bone mass, estrogen status, and metabolic hormones. METHODS: Twenty-four virgin female Sprague-Dawley rats (n = 8/group) were divided into three groups-ad libitum fed + exercise (Adlib + EX), 40 % energy restricted + exercise (ER + EX), and 40 % energy restricted + sedentary (ER + SED). Energy availability between ER groups was equal. Treadmill running was performed 4 days/week at 70 % VO2max for 12 weeks. RESULTS: Fat and lean mass and areal bone mineral density (aBMD) were lower after 12 weeks (p < 0.05) for ER + EX vs Adlib + EX, but ER + EX aBMD was higher than ER + SED (p < 0.0001). Serum leptin and a urinary estrogen metabolite, estrone-1-glucuronide (E1G), were lower at week 12 (p = 0.0002) with ER, with no impact of exercise. Serum insulin-like growth factor I (IGF-I) declined (p = 0.02) from baseline to week 12 in both ER groups. ER + EX exhibited higher cortical volumetric bone mineral density (vBMD) at the midshaft tibia (p = 0.006) vs ER + SED. CONCLUSION: Exercise during ER mitigated some, but not all, of the bone loss observed in sedentary ER rats, but had little impact on changes in urinary E1G and serum IGF-I and leptin. These data highlight the importance of both adequate energy intake and the mechanical loading of exercise in maintaining bone mass.


Assuntos
Densidade Óssea , Doenças Ósseas Metabólicas/prevenção & controle , Restrição Calórica , Estrogênios/urina , Condicionamento Físico Animal , Animais , Feminino , Fator de Crescimento Insulin-Like I/análise , Leptina/sangue , Ratos , Ratos Sprague-Dawley
4.
Heredity (Edinb) ; 114(2): 207-19, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25248465

RESUMO

The spliceosome, constituted by a protein set associated with small nuclear RNA (snRNA), is responsible for mRNA maturation through intron removal. Among snRNA genes, U1 is generally a conserved repetitive sequence. To unveil the chromosomal/genomic dynamics of this multigene family in grasshoppers, we mapped U1 genes by fluorescence in situ hybridization in 70 species belonging to the families Proscopiidae, Pyrgomorphidae, Ommexechidae, Romaleidae and Acrididae. Evident clusters were observed in all species, indicating that, at least, some U1 repeats are tandemly arrayed. High conservation was observed in the first four families, with most species carrying a single U1 cluster, frequently located in the third or fourth longest autosome. By contrast, extensive variation was observed among Acrididae, from a single chromosome pair carrying U1 to all chromosome pairs carrying it, with occasional occurrence of two or more clusters in the same chromosome. DNA sequence analysis in Eyprepocnemis plorans (species carrying U1 clusters on seven different chromosome pairs) and Locusta migratoria (carrying U1 in a single chromosome pair) supported the coexistence of functional and pseudogenic lineages. One of these pseudogenic lineages was truncated in the same nucleotide position in both species, suggesting that it was present in a common ancestor to both species. At least in E. plorans, this U1 snDNA pseudogenic lineage was associated with 5S rDNA and short interspersed elements (SINE)-like mobile elements. Given that we conclude in grasshoppers that the U1 snDNA had evolved under the birth-and-death model and that its intragenomic spread might be related with mobile elements.


Assuntos
Genoma de Inseto , Gafanhotos/genética , Família Multigênica , Ribonucleoproteína Nuclear Pequena U1/genética , Animais , Evolução Biológica , Mapeamento Cromossômico , Cromossomos , Sequência Conservada , Feminino , Masculino , Dados de Sequência Molecular
5.
Physiol Behav ; 120: 26-33, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23831742

RESUMO

Acylated ghrelin and peptide YY (PYY3-36) are involved in appetite-regulation and energy homeostasis. These gastrointestinal hormones provide peripheral signals to the central nervous system to regulate appetite and short term food intake, and interact with leptin and insulin to regulate energy balance. Dietary restraint is an eating behavior phenotype that manifests as a conscious cognitive control of food intake in order to achieve or sustain a desired body weight. The purpose of the current study was to determine if college-aged women (18 to 25 years) with different eating behavior phenotypes, i.e., high vs normal dietary restraint, differ with respect to circulating concentrations of gastrointestinal hormones during and following a test meal. We hypothesized that women with high dietary cognitive restraint [High CR (score ≥ 13, n=13)] would have elevated active ghrelin and PYY3-36 concentrations after a test meal compared to women with normal dietary cognitive restraint [Normal CR (score < 13, n=30)]. Gastrointestinal hormones were assessed before (-15 and 0 min) and after (10, 15, 20, 30, 60, 90, 120 and 180 min) the consumption of a mixed composition meal (5.0 kcal per kg/body weight). In contrast to our hypothesis, mean PYY3-36 concentrations (p=0.042), peak PYY3-36 concentrations (p=0.047), and PYY3-36 area under the curve (p=0.035) were lower in the High CR group compared to the Normal CR group after controlling for body mass index. No group differences were observed with respect to acylated ghrelin before or after the meal. In conclusion, PYY3-36 concentrations were suppressed in the women with High CR compared to the women with Normal CR. While the current study is cross-sectional and cause/effect of high dietary restraint and suppressed PYY3-36 concentrations cannot be determined, we speculate that these women with high cognitive restraint may be prone to weight gain or weight re-gain related to the suppressed circulating PYY after a meal. Further investigations need to explore the relationship between dietary cognitive restraint, circulating PYY, and weight gain.


Assuntos
Cognição/fisiologia , Peptídeo YY/metabolismo , Período Pós-Prandial/fisiologia , Adolescente , Antropometria , Apetite , Índice de Massa Corporal , Dieta , Ingestão de Alimentos/fisiologia , Ingestão de Alimentos/psicologia , Feminino , Grelina/sangue , Humanos , Análise de Regressão , Inquéritos e Questionários , Adulto Jovem
6.
Cytogenet Genome Res ; 135(2): 111-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21893968

RESUMO

Phosphorylation of serine 10 in histone H3 (H3S10ph) has been extensively analyzed and appears to be a conserved chromatin change associated with chromosome condensation in different eukaryotic organisms. In this work, we report the distribution of H3S10ph during meiosis in monocentric and holokinetic chromosomes of 6 insect species and in mitotic chromosomes of 7 mammalian species, aiming to investigate the labeling patterns in phylogenetically distant groups. The results indicated a very similar phosphorylation timing and distribution pattern among insects. The sex chromosomes of insects analyzed were always undercondensed and hypophosphorylated. Similarly, the micro chromosomes of the bug Pachylis aff pharaonis were also undercondensed and hypophosphorylated. Holokinetic chromosomes of bugs and monocentric chromosomes of grasshoppers and beetles displayed identical phosphorylation pattern in spite of the difference in the centromere type. Among mammals, a uniform chromosome phosphorylation was observed in marsupials, whereas bat chromosomes displayed a longitudinal banding pattern. These data indicate that, in general, the intensity of H3S10 phosphorylation in animal chromosomes is variable among the distinct chromosome types and associated with the degree of chromatin condensation at metaphase, but it may vary between different groups of animals.


Assuntos
Cromossomos de Insetos/metabolismo , Cromossomos de Mamíferos/metabolismo , Histonas/metabolismo , Serina/metabolismo , Animais , Quirópteros , Cromatina/genética , Cromatina/metabolismo , Cromossomos de Insetos/genética , Cromossomos de Mamíferos/genética , Besouros , Gafanhotos , Meiose/genética , Metáfase/genética , Mitose/genética , Gambás , Fosforilação , Especificidade da Espécie
7.
Bone ; 49(2): 194-201, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21549231

RESUMO

BACKGROUND: In women with anorexia nervosa, elevated fasting peptide YY (PYY) is associated with decreased bone mineral density (BMD). Prior research from our lab has demonstrated that fasting total PYY concentrations are elevated in exercising women with amenorrhea compared to ovulatory exercising women. PURPOSE: The purpose of this study was to assess the association between fasting total PYY, average monthly estrogen exposure and BMD in non-obese premenopausal exercising women. METHODS: Daily urine samples were collected and assessed for metabolites of estrone 1-glucuronide (E1G) and pregnandiol glucuronide (PdG) for at least one menstrual cycle if ovulatory or a 28-day monitoring period if amenorrheic. Fasting serum samples were pooled over the measurement period and analyzed for total PYY and leptin. BMD and body composition were assessed by dual-energy X-ray absorptiometry. Multiple regression analyses were performed to determine whether measures of body composition, estrogen status, exercise minutes, leptin and PYY explained a significant amount of the variance in BMD at multiple sites. RESULTS: Premenopausal exercising women aged 23.8±0.9years with a mean BMI of 21.2±0.4kg/m(2) exercised 346±48min/week and had a peak oxygen uptake of 49.1±1.8mL/kg/min. Thirty-nine percent (17/44) of the women had amenorrhea. Fasting total PYY concentrations were negatively associated with total body BMD (p=0.033) and total hip BMD (p=0.043). Mean E1G concentrations were positively associated with total body BMD (p=0.033) and lumbar spine (L2-L4) BMD (p=0.047). The proportion of variance in lumbar spine (L2-L4) BMD explained by body weight and E1G cycle mean was 16.4% (R(2)=0.204, p=0.012). The proportion of variance in hip BMD explained by PYY cycle mean was 8.6% (R(2)=0.109, p=0.033). The proportion of variance in total body BMD explained by body weight and E1G cycle mean was 21.9% (R(2)=0.257, p=0.003). CONCLUSION: PYY, mean E1G and body weight are associated with BMD in premenopausal exercising women. Thus, elevated PYY and suppressed estrogen concentrations are associated with, and could be directly contributing to, low BMD in exercising women with amenorrhea, despite regular physical activity.


Assuntos
Densidade Óssea/fisiologia , Estrogênios/sangue , Exercício Físico/fisiologia , Peptídeo YY/sangue , Absorciometria de Fóton , Adolescente , Adulto , Amenorreia/sangue , Amenorreia/urina , Estrona/urina , Jejum/sangue , Feminino , Humanos , Leptina/sangue , Pregnanodiol/análogos & derivados , Pregnanodiol/urina , Pré-Menopausa/sangue , Pré-Menopausa/urina , Adulto Jovem
8.
Hum Reprod ; 26(3): 685-94, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21227945

RESUMO

BACKGROUND: Low concentrations of leptin secondary to low body fat or other modulators are thought to be a key signal whereby an energy deficit suppresses the reproductive axis in exercising women resulting in functional hypothalamic amenorrhea (FHA). The purpose of this study was to first examine leptin concentrations in exercising women with and without FHA to address whether there is a threshold concentration of leptin below which reproductive function is suppressed. Secondly, we examined the role of adiposity and other possible modulators of leptin to ascertain whether leptin regulation differs depending on reproductive status. METHODS: This study assessed 50 exercising, premenopausal women (aged 18-30 years) over the course of one menstrual cycle (eumenorrheic women) or one 28-day monitoring period (amenorrheic women). Quantification of daily urinary ovarian steroids and menstrual history were used to determine menstrual status. Body composition was assessed using dual energy X-ray absorptiometry, and leptin was determined by enzyme-linked immunoassay. Key modulators of leptin such as serum insulin concentration, carbohydrate intake, glucose availability, indirect indices of sympathetic nervous activity and other factors were assessed using linear regression. RESULTS: Percentage body fat (%BF) (21.0 ± 1.0 versus 26.8 ± 0.7%; P < 0.001) and leptin concentration (4.8 ± 0.8 versus 9.6 ± 0.9 ng/ml; P < 0.001) were lower in the exercising women with amenorrhea (ExAmen; n = 24) compared with the exercising ovulatory women (ExOvul; n = 26). However, the ranges in leptin were similar for each group (ExAmen: 0.30-16.98 ng/ml; ExOvul: 2.57-18.28 ng/ml), and after adjusting for adiposity the difference in leptin concentration was no longer significant. Significant predictors of log leptin in ExAmen included %BF (ß = 0.826, P < 0.001), log insulin (ß = 0.308, P = 0.012) and log glycerol (ß = 0.258, P = 0.030), but in ExOvul only %BF predicted leptin. CONCLUSIONS These data suggest that leptin concentrations per se are not associated with FHA in exercising women, but the modulation of leptin concentrations may differ depending on reproductive status.


Assuntos
Amenorreia/sangue , Exercício Físico , Leptina/sangue , Ciclo Menstrual/sangue , Absorciometria de Fóton , Adiposidade , Adolescente , Adulto , Amenorreia/epidemiologia , Amenorreia/urina , Glicemia/análise , Estudos Transversais , Carboidratos da Dieta/administração & dosagem , Estrona/análogos & derivados , Estrona/urina , Exercício Físico/fisiologia , Feminino , Glucuronídeos/urina , Glicerol/sangue , Humanos , Insulina/sangue , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Ciclo Menstrual/urina , Pregnanodiol/análogos & derivados , Pregnanodiol/urina , Adulto Jovem
9.
Hum Reprod ; 25(9): 2328-39, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20605898

RESUMO

BACKGROUND: Alterations in circulating steroids are believed to be important mediators of the impact that diet and exercise have on breast cancer risk and changes in bone density. This study aimed to test the hypothesis that moderate exercise training combined with caloric restriction would produce significant menstrual disturbances and alterations in ovarian steroids in premenopausal women. METHODS: Sedentary premenopausal women (25-40 years; body mass index: 23.6 +/- 0.6 kg/m(2)) assigned to either a light conditioning (LC, n = 9) or an exercise combined with caloric restriction group (EX + CR, n = 24) were studied for one screening, one baseline and four intervention periods equivalent to the length of subjects' menstrual cycles. Exercise consisted of supervised training sessions, i.e. two LC or four EX + CR times per week, 30-60 min at a moderate intensity. The EX + CR group was prescribed a diet representing a caloric restriction of 20-35% below baseline energy requirements, whereas the LC group remained eucaloric. Ovarian steroid exposure was determined with daily urinary estrone-1- and pregnanediol glucuronides (E1G and PdG, respectively) and mid-cycle urinary LH measures. Fitness, body composition, and serum sex hormone binding globulin (SHBG) and serum estradiol (E2) were assessed repeatedly. RESULTS: The intervention produced significant increases in VO(2) max and decreases in both body weight (-3.7 +/- 0.5 kg; ranged from -8.8 to +1.8 kg) and percent body fat (-4.5 +/- 0.7%; ranged from -12 to +0.3%), which were attributable primarily to changes in the EX + CR subjects (time x group; P < 0.05). Serum E2 and urinary E1G and PdG concentrations declined significantly across the intervention period (time; P < 0.05), whereas SHBG increased transiently (time; P < 0.05) in the EX + CR subjects, with no significant changes observed in the LC group. The decrease in E1G area under the curve was significantly related to the daily energy deficit (R =0.61; P = 0.003), not the amount of weight lost. There was no significant impact of the intervention on menstrual cyclicity or the incidence of menstrual disturbances in either group. CONCLUSIONS: A moderate aerobic exercise training program combined with modest weight loss in accordance with recommended guidelines produces significant reductions in ovarian steroid exposure without disrupting menstrual cyclicity in premenopausal women aged 25-40 years. Exposure to a daily energy deficit is a stronger predictor of the decline in estrogen exposure than decreases in body weight.


Assuntos
Restrição Calórica/efeitos adversos , Estrogênios/urina , Exercício Físico , Ciclo Menstrual , Distúrbios Menstruais/epidemiologia , Progesterona/urina , Adulto , Composição Corporal , Neoplasias da Mama/epidemiologia , Estradiol/sangue , Estrona/urina , Feminino , Glucuronídeos/urina , Humanos , Hormônio Luteinizante/urina , Ciclo Menstrual/sangue , Ciclo Menstrual/urina , Distúrbios Menstruais/sangue , Distúrbios Menstruais/metabolismo , Distúrbios Menstruais/urina , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Consumo de Oxigênio , Aptidão Física , Pregnanodiol/análogos & derivados , Fatores de Risco , Globulina de Ligação a Hormônio Sexual/análise , Redução de Peso
10.
Hum Reprod ; 25(2): 491-503, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19945961

RESUMO

BACKGROUND: The identification of subtle menstrual cycle disturbances requires daily hormone assessments. In contrast, the identification of severe menstrual disturbances, such as amenorrhea and oligomenorrhea, can be established by clinical observation. The primary purpose of this study was to determine the frequency of subtle menstrual disturbances, defined as luteal phase defects (LPD) or anovulation, in exercising women, with menstrual cycles of 26-35 days, who engage in a variety of sports, both recreational and competitive. Secondly, the prevalence of oligomenorrhea and amenorrhea was also determined via measurement of daily urinary ovarian steroids rather than self report alone. METHODS: Menstrual status was documented by daily measurements of estrone and pregnanediol glucuronide and luteinizing hormone across two to three consecutive cycles and subsequently categorized as ovulatory (Ovul), LPD, anovulatory (Anov), oligomenorrheic (Oligo) and amenorrheic (Amen) in sedentary (Sed) and exercising (Ex) women. RESULTS: Sed (n = 20) and Ex women (n = 67) were of similar (P > 0.05) age (26.3 +/- 0.8 years), weight (59.3 +/- 1.8 kg), body mass index (22.0 +/- 0.6 kg/m2), age of menarche (12.8 +/- 0.3 years) and gynecological maturity (13.4 +/- 0.9 years). The Sed group exercised less (P < 0.001) (96.7 +/- 39.1 versus 457.1 +/- 30.5 min/week) and had a lower peak oxygen uptake (34.4 +/- 1.4 versus 44.3 +/- 0.6 ml/kg/min) than the Ex group. Among the menstrual cycles studied in the Sed group, the prevalence of subtle menstrual disturbances was only 4.2% (2/48); 95.8% (46/48) of the observed menstrual cycles were ovulatory. This finding stands in stark contrast to that observed in the Ex group where only 50% (60/120) of the observed menstrual cycles were ovulatory and as many as 50% (60/120) were abnormal. Of the abnormal cycles in the Ex group, 29.2% (35/120) were classified as LPD (short, inadequate or both) and 20.8% (25/120) were classified as Anov. Among the cycles of Ex women with severe menstrual disturbances, 3.5% (3/86) of the cycles were Oligo and 33.7% (29/86) were Amen. No cycles of Sed women (0/20) displayed either Oligo or Amen. CONCLUSIONS: This study suggests that approximately half of exercising women experience subtle menstrual disturbances, i.e. LPD and anovulation, and that one third of exercising women may be amenorrheic. Estimates of the prevalence of subtle menstrual disturbances in exercising women determined by the presence or absence of short or long cycles does not identify these disturbances. In light of known clinical consequences of menstrual disturbances, these findings underscore the lack of reliability of normal menstrual intervals and self report to infer menstrual status.


Assuntos
Exercício Físico/fisiologia , Ciclo Menstrual/fisiologia , Distúrbios Menstruais/etiologia , Ovulação/fisiologia , Adulto , Amenorreia/etiologia , Anovulação/etiologia , Estrona/análogos & derivados , Estrona/urina , Feminino , Humanos , Fase Luteal/fisiologia , Hormônio Luteinizante/urina , Distúrbios Menstruais/metabolismo , Oligomenorreia/etiologia , Pregnanodiol/análogos & derivados , Pregnanodiol/urina , Progesterona/urina , Estudos Prospectivos , Esportes/fisiologia
11.
Osteoporos Int ; 19(4): 465-78, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18180975

RESUMO

UNLABELLED: Functional hypothalamic amenorrhea (FHA) impairs the attainment of peak bone mass and as such can increase the risk of fractures later in life. To document available treatment strategies, we conducted a systematic review of the literature. We report that hormonal therapies have limited effectiveness in increasing bone mass, whereas increased caloric intake resulting in weight gain and/or resumption of menses is an essential strategy for restoring bone mass in women with FHA. INTRODUCTION: Women with functional hypothalamic amenorrhea (FHA) may not achieve peak bone mass (PBM), which increases the risk of stress fractures, and may increase the risk of osteoporotic fractures in later life. METHODS: To identify effective treatment strategies for women with FHA, we conducted a systematic review of the literature. We included randomized controlled trials (RCTs), cross-sectional studies, and case studies that reported on the effects of pharmacological and non-pharmacological interventions on bone mineral density (BMD) or bone turnover in women with FHA. RESULTS: Most published studies (n=26) were designed to treat the hormonal abnormalities observed in women with FHA (such as low estrogen, leptin, insulin-like growth factor-1, and DHEA); however none of these treatments demonstrated consistent improvements in BMD. Therapies containing an estrogen given for 8-24 months resulted in variable improvements (1.0-19.0%) in BMD, but failed to restore bone mass to that of age-matched controls. Three studies reported on the use of bisphosphonates (3-12 months) in anorexic women, which appear to have limited effectiveness to improve BMD compared to nutritional treatments. Another three investigations showed no improvements in BMD after androgen therapy (DHEA and testosterone) in anorexic women. In contrast, reports (n=9) describing an increase in caloric intake that results in weight gain and/or the resumption of menses reported a 1.1-16.9% increase in BMD concomitant with an improvement in bone formation and reduction in bone resorption markers. CONCLUSIONS: Our literature review indicates that the most successful, and indeed essential strategy for improving BMD in women with FHA is to increase caloric intake such that body mass is increased and there is a resumption of menses. Further long-term studies to determine the persistence of this effect and to determine the effects of this and other strategies on fracture risk are needed.


Assuntos
Amenorreia/patologia , Anorexia Nervosa/complicações , Fraturas Ósseas/prevenção & controle , Doenças Hipotalâmicas/patologia , Osteoporose/prevenção & controle , Adolescente , Adulto , Amenorreia/complicações , Ingestão de Energia/fisiologia , Métodos Epidemiológicos , Feminino , Fraturas Ósseas/dietoterapia , Humanos , Doenças Hipotalâmicas/complicações , Pessoa de Meia-Idade , Osteoporose/dietoterapia , Osteoporose/fisiopatologia , Resultado do Tratamento , Aumento de Peso/fisiologia
13.
Hereditas ; 134(3): 189-94, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11833280

RESUMO

This paper provides new data on chromosomes of Brazilian vampire bats Desmodus rotundus and Diphylla ecaudata. These species were analyzed by GTG, CBG- and CB-DAPI banding, AgNO3/CMA3 sequential staining, base-specific fluorochrome dyes and in situ hybridization with 18S rDNA probe. C-banding (CBG) revealed constitutive heterochromatin in the pericentromeric regions in all autosomes and the X and Y chromosomes appeared entirely heterochromatic in both species. CB-DAPI revealed a coincident banding pattern to that obtained by CBG. Triple staining CMA3/DA/DAPI revealed an R-banding and a weak G-banding pattern in the karyotypes. Sequential AgNO3/CMA3 staining showed a NOR located interstitially on the long arm of pair 8 in D. rotundus and on the short arm of pair 13 in D. ecaudata. FISH with a rDNA probe confirmed the location and number of NORs; a difference neither in intensity nor in size of hybridization signal was detected between homologues for both species.


Assuntos
Quirópteros/genética , Cromossomos/química , Corantes Fluorescentes/química , Genes de RNAr , Animais , Brasil , Centrômero/química , Bandeamento Cromossômico , Cromossomos/ultraestrutura , Feminino , Fluorescência , Heterocromatina/genética , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Região Organizadora do Nucléolo/genética , Sensibilidade e Especificidade , Coloração pela Prata , Cromossomo X , Cromossomo Y
14.
Cytobios ; 103(403): 111-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11077973

RESUMO

The constitutive heterochromatin (CH) of Phaeoparia megacephala was studied using C-banding and fluorochrome staining (CMA3, DAPI and acridine orange). The nucleolar organizer regions (NOR) were identified with silver staining. The chromosome complement of this species was 2n = 23, XO in males, and 2n = 24, XX in females. The CH was pericentromeric in all chromosomes. L1, L2, L3 and X chromosomes showed large blocks of CH, while the medium and small chromosomes had small blocks. The staining procedure with acridine orange revealed the same pattern. All the pericentromeric regions showed small blocks of CMA3-positive constitutive heterochromatin (GC-rich regions), while only part of the large C-band positive chromosome segments (L1, L2, L3 and X) were CMA3 positive. This character demonstrates an uncommon heterogeneity of constitutive heterochromatin in P. megacephala. The fluorochrome DAPI did not reveal DAPI-positive regions (AT-rich regions). Silver staining revealed only one pair of medium chromosomes with NOR.


Assuntos
Gafanhotos/genética , Heterocromatina/genética , Região Organizadora do Nucléolo/genética , Animais , Bandeamento Cromossômico , Feminino , Cariotipagem/métodos , Masculino , Coloração pela Prata
15.
Menopause ; 7(5): 318-26, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10993031

RESUMO

OBJECTIVES: The purpose of this investigation was to evaluate the relative efficacy of the sublingual administration of micronized estradiol (E2), progesterone (P4), and testosterone (T) on bone mineral density and biochemical markers of bone metabolism. DESIGN: In this double-blind, prospective study, postmenopausal women were randomly assigned to one of four treatment groups: hysterectomized women were assigned to either 1) micronized E2 (0.5 mg) or 2) micronized E2 (0.5 mg) + micronized T (1.25 mg). Women with intact uteri were assigned to either 3) micronized E2 (0.5 mg) + micronized P4 (100 mg) or 4) micronized E2 (0.5 mg) + micronized P4 (100 mcg) + micronized T (1.25 mg). For the purpose of this study, the four treatment groups were combined into two groups for all comparisons. The E2 and E2+P4 groups were combined into the HRT alone group (n=30), and the E2+T and E2+P4+T groups were combined into the HRT + T group (n=27). Hormones were administered sublingually as a single tablet twice a day for 12 months. Bone mineral density was measured in the anterior-posterior lumbar spine and total left hip via dual energy x-ray absorptiometry. Bone metabolism was assessed via serum bone-specific alkaline phosphatase and urinary deoxypyridinoline and cross-linked N-telopeptide of type I collagen, both normalized to creatinine. Data were analyzed via a repeated measures analysis of variance and a Student's t test (alpha=0.05). RESULTS: The subjects were of similar age (54.0 +/- 0.8 years), height (64.0 +/- 0.3 in), weight (157.6 +/- 4.2 lb), and had similar baseline follicle-stimulating hormone (66.4 +/- 3.2 mIU/L), E2 (26.4 +/- 1.5 pg/ml), P4 (0.3 +/- 0.1 ng/ml), total T (19.0 +/- 1.5 ng/dL), and bioavailable T (3.7 +/- 0.3 ng/dL) levels. During therapy, serum levels increased (p < 0.05) for each hormone. Bone mineral density and bone markers at baseline were similar for each treatment group. Bone-specific alkaline phosphatase decreased (p < 0.05) by -14.3 +/- 4.1% in the HRT alone group and by -8.2 +/- 4.6% in the HRT + T group. Deoxypyridinoline levels decreased significantly in the HRT alone and HRT + T groups, - 14.4 +/- 6.8% and -26.9 +/- 7.6%, respectively. Significant reductions (p < 0.05) in cross-linked N-telopeptide of type I collagen were also observed in both groups, -24.4 +/- 6.5% and -39.5 +/- 8.6%, respectively. Bone mineral density in the lumbar spine increased (p < 0.05) by +2.2 +/- 0.5% the HRT alone group and by + 1.8 +/- 0.6% in the HRT + T group. Total hip bone mineral density was maintained in the HRT alone group (+0.4 +/- 0.4%) and increased (p < 0.05) in the HRT + T group (+ 1.8 +/- 0.5%). CONCLUSIONS: Sublingual micronized HRT favorably decreases serum and urine markers of bone metabolism, prevents bone loss, and results in a slight increase in spine and hip bone mineral density. Although the addition of testosterone to HRT for 1 year did not result in added benefit to the spine bone mineral density, it did result in a significant increase in hip bone mineral density. Longer duration of therapy may have further improved these outcomes.


Assuntos
Densidade Óssea/efeitos dos fármacos , Osso e Ossos/metabolismo , Estradiol/farmacologia , Terapia de Reposição Hormonal , Osteoporose Pós-Menopausa/prevenção & controle , Progesterona/farmacologia , Testosterona/farmacologia , Administração Sublingual , Fosfatase Alcalina/sangue , Aminoácidos/urina , Colágeno/urina , Método Duplo-Cego , Estradiol/administração & dosagem , Estradiol/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Progesterona/administração & dosagem , Progesterona/uso terapêutico , Estudos Prospectivos , Testosterona/administração & dosagem , Testosterona/uso terapêutico
16.
Cytobios ; 101(398): 137-44, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10755212

RESUMO

Conventional analysis, C-banding, silver nitrate and base specific fluorochrome staining with chromomycin A3 (CMA3) were used to analyse the meiotic chromosomes of the grasshopper Stiphra robusta. Diploid numbers of 2n = 19 in the males and 2n = 20 in the females were observed. The chromosome complement comprised a graded series of uniarmed chromosomes, and the X chromosome was medium sized. The nucleolar organizer regions, restricted to the bivalent chromosomes 6, 7 and 8, were CMA3 positive.


Assuntos
Gafanhotos/genética , Heterocromatina/genética , Animais , Feminino , Cariotipagem , Masculino
17.
J Clin Endocrinol Metab ; 83(12): 4220-32, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9851755

RESUMO

The purposes of this investigation were to evaluate the characteristics of three consecutive menstrual cycles and to determine the frequency ofluteal phase deficiency (LPD) and anovulation in a sample of sedentary and moderately exercising, regularly menstruating women. For three consecutive menstrual cycles, subjects collected daily urine samples for analysis of FSH, estrone conjugates (E1C), pregnanediol-3-glucuronide (PdG), and creatinine (Cr). Sedentary (n=11) and exercising (n=24) groups were similar in age (27.0+/-1.3 yr), weight (60.3+/-3.1 kg), gynecological age (13.8+/-1.2 yr), and menstrual cycle length (28.3+/-0.8 days). Menstrual cycles were classified by endocrine data as ovulatory, LPD, or anovulatory. No sedentary women (0%) had inconsistent menstrual cycle classifications from cycle to cycle, but 46% of the exercising women were inconsistent. The sample prevalence of LPD in the exercising women was 48%, and the 3-month sample incidence was 79%. In the sedentary women, 90% of all menstrual cycles were ovulatory (SedOvul; n=28), whereas in the exercising women only 45% were ovulatory (ExOvul; n=30); 43% were LPD (ExLPD; n=28), and 12% were anovulatory (ExAnov; n=8). In ExLPD cycles, the follicular phase was significantly longer (17.9+/-0.7 days), and the luteal phase was significantly shorter (8.2+/-0.5 days) compared to ExOvul (14.8+/-0.9 and 12.9+/-0.3 days) and SedOvul (15.9+/-0.6 and 12.9+/-0.4 days) cycles. Luteal phase PdG excretion was lower (P < 0.001) in ExLPD (2.9+/-0.3 microg/mg Cr) and ExAnov (0.8+/-0.1 microg/mg Cr) cycles compared to SedOvul cycles (5.0+/-0.4 microg/mg Cr). ExOvul cycles also had less (P < 0.01) PdG excretion during the luteal phase (3.7+/-0.3 microg/mg Cr) than the SedOvul cycles. E1C excretion during follicular phase days 2-5 was lower (P=0.05) in ExOvul, ExLPD, and ExAnov cycles compared to SedOvul cycles and remained lower (P < 0.02) in the ExLPD and ExAnov cycles during days 6-12. The elevation in FSH during the luteal-follicular transition was lower (P < 0.007) in ExLPD (0.7+/-0.1 ng/mg Cr) cycles compared to SedOvul and ExOvul cycles (1.0+/-0.1 and 1.1+/-0.1 ng/mg Cr, respectively). Energy balance and energy availability were lower (P < 0.05) in ExAnov cycles than in other menstrual cycle categories. The blunted elevation in FSH during the luteal-follicular transition in exercising women with LPD may explain their lower follicular estradiol levels. These alterations in FSH may act in concert with disrupted LH pulsatility as a primary and proximate factor in the high frequency of luteal phase and ovulatory disturbances in regularly menstruating, exercising women.


Assuntos
Anovulação/etiologia , Hormônio Foliculoestimulante/sangue , Fase Folicular/fisiologia , Fase Luteal/fisiologia , Corrida/fisiologia , Adolescente , Adulto , Ingestão de Energia , Metabolismo Energético/fisiologia , Estrogênios/urina , Feminino , Humanos , Ciclo Menstrual/fisiologia , Fenômenos Fisiológicos da Nutrição/fisiologia , Educação Física e Treinamento , Progesterona/urina , Recreação/fisiologia
18.
J Clin Endocrinol Metab ; 82(9): 2867-76, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9284712

RESUMO

The primary purpose of this study was to determine whether decreased ovarian progesterone production, associated with short and inadequate luteal phases in exercising women, was associated with decreased bone mineral density (BMD) and altered bone metabolism. Thirty-three eumenorrheic menstruating women participated in this study for 3 months. Subjects were required to collect daily urine samples for three consecutive menstrual cycles and have blood and urine collected weekly. Daily urine samples were analyzed for free LH, estrone conjugates (E1C), and pregnanediol 3-glucuronide (PdG), adjusted for creatinine, whereas weekly blood and urine samples were analyzed for bone markers, estradiol, progesterone, FSH, and LH. Based on the analyses of these samples, subjects were divided into three groups: sedentary ovulatory (SedOvul; n = 9), exercising ovulatory (ExOvul; n = 14), and exercising luteal phase defects (ExLPD; n = 10). The three groups were matched for age (27.6 +/- 1.0 yr), weight (60.6 +/- 1.9 cm), and reproductive maturity (14.5 +/- 1.0 yr), PdG production during the luteal phase was lower (P = 0.004) in the ExLPD women compared to that in the SedOvul group (2.4 +/- 0.4 vs. 5.1 +/- 0.6 ng/mL creatinine, respectively). The ExOvul group also had less (P < 0.01) PdG production during the luteal phase (3.5 +/- 0.3 ng/mL creatinine) compared to the SedOvul group. The total production of PdG, as assessed by area under the curve analysis, was also lower (P < 0.001) in the ExOvul and ExLPD groups compared to that in the SedOvul group. E1C production, however, was not different (P > 0.05) among the groups, except for E1C during the early follicular phase, which was lower (P = 0.043) in the ExLPD group than that in the SedOvul group. BMD and biochemical markers of bone metabolism were unaffected by and not associated with the compromised progesterone environment, but BMD values at the proximal femur (r = 0.354; P = 0.061) and total body (r = 0.359; P = 0.056) were associated with decreased early follicular E1C production. We conclude the following. 1) Luteal phase disturbances occur independent of training volume, and volume of training does not have to be severe to result in menstrual disturbances. 2) As a result of exercise, disturbance in progesterone production is not associated with decreased bone mass. 3) Long follicular phases are associated with reduced estrogen production during the early follicular phase, which are both associated with decreased bone mass. 4) Provided the estradiol status is adequately maintained, BMD is unaffected by decreased progesterone production associated with short and inadequte luteal phases in exercising women.


Assuntos
Osso e Ossos/fisiologia , Nível de Saúde , Fase Luteal/fisiologia , Ovário/metabolismo , Progesterona/biossíntese , Corrida/fisiologia , Adolescente , Adulto , Biomarcadores , Densidade Óssea , Feminino , Humanos , Ciclo Menstrual/fisiologia , Osteogênese/fisiologia
19.
Contraception ; 56(2): 59-65, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9315413

RESUMO

Several authors have suggested that estrogen may serve to protect skeletal muscle from exercise-induced damage. The present study examined the effects of regularly ingesting estrogen, in the form of oral contraceptives, on postexercise muscle damage following a bench-stepping regimen. Women currently ingesting oral contraceptives (OC) were compared with eumennorheic controls (CG). All subjects performed a 50-min stepping exercise during the midluteal phase of their menstrual cycle. Muscle damage was evaluated on 2, 3, and 5 days postexercise using several established indirect indicators: perceived soreness, strength and range of motion changes, girth measurements, and creatine kinase (CK) activity. Subjects on OC reported significantly lower quadriceps soreness (p < 0.05) relative to the CG (peak soreness = 4.0 and 7.8, respectively, on a scale of 1-10 where 1 is normal and 10 is very, very sore). These results indicate that oral contraceptive use attenuates soreness following an exhaustive stepping activity but cannot support a relationship between estrogen ingestion and other indices of exercise-induced muscle damage.


Assuntos
Anticoncepcionais Orais/uso terapêutico , Exercício Físico , Músculos/lesões , Adulto , Creatina Quinase/análise , Feminino , Humanos , Fase Luteal , Músculos/enzimologia , Dor
20.
Rev Bras Enferm ; 50(3): 345-62, 1997.
Artigo em Português | MEDLINE | ID: mdl-9775944

RESUMO

This research is of qualitative nature and it aims at studying nurse's social representations towards nursing and its professional practice and the way they effectively accomplish this practice at Rio de Janeiro Federal University San Francisco de Assisi School Hospital (HESFA/UFRJ). Data were collected from interview, campus observations and documents. Data analysis reveal contradictions and conflicts experienced by nurses in their professional praxis. They are beginning a process of reflection on their professional autonomy: they are sorry for the lack of structure is assisting clients properly; they do believe that researching and political participation are essential for profession development.


Assuntos
Atitude do Pessoal de Saúde , Cuidados de Enfermagem/organização & administração , Recursos Humanos de Enfermagem Hospitalar/psicologia , Brasil , Conflito Psicológico , Hospitais de Ensino , Humanos , Pesquisa Metodológica em Enfermagem , Autonomia Profissional , Inquéritos e Questionários
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