ABSTRACT
Polyurethane (PU) has been used in a variety of industries during the past few years due to its exceptional qualities, including strong mechanical strength, good abrasion resistance, toughness, low-temperature flexibility, etc. More specifically, PU is easily "tailored" to satisfy particular requirements. There is a lot of potential for its use in broader applications due to this structure-property link. Ordinary polyurethane items cannot satisfy people's increased demands for comfort, quality, and novelty as living standards rise. The development of functional polyurethane has recently received tremendous commercial and academic attention as a result. In this study, the rheological behavior of a polyurethane elastomer of the PUR (rigid polyurethane) type was examined. The study's specific goal was to examine stress relaxation for various bands of specified strains. We also suggested the use of a modified Kelvin-Voigt model to describe the stress relaxation process from the perspective of the author. For the purpose of verification, materials with two different Shore hardness ratings-80 and 90 ShA, respectively-were chosen. The outcomes made it possible to positively validate the suggested description in a variety of deformations ranging from 50% to 100%.
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INTRODUCTION: Changes in sex hormone secretions during the menstrual cycle may affect fertility. It has been shown that a prematurely raised progesterone (P4) level after therapeutic injection of human chorionic gonadotropin caused changes in endometrial gene expression and lowered the pregnancy rate. The aim of the present study was to investigate the complete menstrual patterns of P4 together with its derivatives testosterone (T) and oestradiol (E2) in subfertile women during their natural cycles. MATERIAL AND METHODS: Daily serum levels of P4 (ng/mL), T (ng/mL), E2 (pg/mL), and sex hormone binding protein (SHBG, nmol/L) were measured throughout a single 23-28-day menstrual cycle in 15 subfertile women aged 28-40 years with patent oviducts and normospermic partners. Knowing SHBG levels, the free androgen (FAI) and free oestrogen (FEI) indexes were calculated for each cycle day in each patient. RESULTS: Baseline (cycle day one) levels of luteinising hormone (LH), thyroid stimulating hormone (TSH), P4, and T were comparable with reference intervals for a normal cycle, whereas follicle stimulating hormone (FSH), E2, and SHBG exceeded those. During cycles, the levels of P4 correlated positively with E2 levels (r = 0.38, p < 0.05, n = 392) an negatively with T (r = -0.13, p < 0.05, n = 391). T correlated negatively with E2 (r = -0.19, p < 0.05, n = 391). Menstrual cycle phases were hidden. The curve of the mean/median daily levels of P4 rose prematurely, was parallel with the E2 rise, and culminated closely, but with more than 4 times greater amplitude of P4 (2571% of baseline levels in day 16) than of E2 (580% in day 14). In turn, the curve of T declined in a U-shaped manner with a nadir (-27%) on day 16. Averaged daily levels of FEI, but not FAI, varied significantly between 23 and 26 days long and the 27-28-day cycles. CONCLUSIONS: 1. Throughout the entire menstrual cycle length in subfertile women, P4 secretion predominates quantitatively over secretions of the remaining sex hormones when menstrual cycle phases are hidden. 2. The rise of E2 secretion is in parallel with the P4 rise, but with 4 times lower amplitude of E2. 3. T secretion declines and is inversely related to both P4 and E2 secretions. 4. Changes in E2 bioavailability are related to menstrual cycle length.
Subject(s)
Gonadal Steroid Hormones , Progesterone , Animals , Pregnancy , Female , Humans , Menstrual Cycle , Fertility , AndrogensABSTRACT
This paper presents the results of a study of polyurethane rigid (PUR) elastomers in terms of the constitutive law identification, and analyses the effect of polyurethane elastomers' hardness on fatigue properties. The research objects were PUR materials based on 4,4'-diphenylmethane diisocyanate (MDI) with the hardness of 80 ShA and 90 ShA, typically used in various industrial applications. Based on the performed experimental campaign under static and cyclic loading, the constitutive model proposed by Ogden is most appropriate. In addition, a hybrid numerical-experimental analysis (using FEM-DIC) of diabolo specimens' behaviour is carried out in fatigue tests. Based on the performed fatigue test, it is worth noting that the energy approach describes the fatigue process synonymously compared to the displacement or strain approach. Finally, simple fatigue characteristics were analyzed and statistically validated for both PUR material configurations.
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In this study, we retrospectively investigated GPER expression in biopsies of azoospermic men with complete (obstructive azoospermia-OA) and aberrant spermatogenesis (nonobstructive azoospermia-NOA). Each biopsy was histologically evaluated with morphometry. The testicular GPER expression was analyzed by the immunohistochemistry and RT-PCR technique in the whole testicular tissue and in seminiferous tubules and Leydig cells after laser-capture microdissection. In laser-microdissected compartments, we also analyzed transcriptional expression of selected Leydig (CYP17A1, HSD17B3, StAR) and Sertoli cell (AMH, SCF, BMP4) function markers. Immunohistochemical staining revealed expression of GPER in the cytoplasm of Leydig and Sertoli cells. Its stronger intensity was observed in Sertoli cells of NOA biopsies. The RT-PCR analysis of the GPER mRNA level unequivocally showed its increased expression in seminiferous tubules (i.e., Sertoli cells), not Leydig cells in NOA biopsies. This increased expression correlated positively with the transcriptional level of AMH-a marker of Sertoli cell immaturity, as well as FSH serum level in NOA but not in the OA group. Our results clearly demonstrate altered GPER expression in testes with primary spermatogenic impairment that might be related to Sertoli cell maturity/function.
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An experimental and analytical approach to the relaxation problem of wood-based materials-OSB (Oriented Strand Boards-pressed wood-based composite panels) beams, including beams with CFRP (Carbon fiber reinforced polymer) tape composite reinforcement, is presented. It is a relevant engineering and scientific problem due to the fact that wood and wood-based materials, as well as composite reinforcements, are widely used in building constructions. Their rheological properties are very important and complicated to estimate. A 10 day long relaxation test of thick OSB beams without reinforcement and with CFRP tape was performed. A four-point bending test with five different bending levels was performed, during which the reduction of the loading force was measured. A five-parameter rheological model was used to describe the rheology of the beams. The equations of this model were calculated with the use of Laplace transform, whereas the values of the parameters were calculated based on the experimental relaxation curves. A high correlation between experimental and theoretical results was obtained. A beam reinforced with CFRP tape was treated as a system with a viscoelastic element (OSB) and an elastic element (CFRP), joined together without the possibility of slipping. The equations of the mathematical model were calculated based on the assumptions of the linear theory of viscoelasticity and the convolution integral. A good correlation between experimental and theoretical results was obtained. A significant redistribution of stresses was observed during the relaxation of the reinforced beam. The reinforced beams show a higher stiffness of approximately 63% and carry proportionally higher loads than unreinforced beams at the same deflection values.
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Concrete is the most widely used construction material nowadays. We are concerned with the computational modelling and laboratory testing of high-performance concrete (HPC). The idea of HPC is to enhance the functionality and sustainability of normal concrete, especially by its greater ductility as well as higher compressive, tensile, and flexural strengths. In this paper, the influence of three types (linear displacement, uniform traction, and periodic) of boundary conditions used in numerical homogenization on the calculated values of HPC properties is determined and compared with experimental data. We take into account the softening behavior of HPC due to the development of damage (micro-cracks), which finally leads to failure. The results of numerical simulations of the HPC samples were obtained by using the Abaqus package that we supplemented with our in-house finite element method (FEM) computer programs written in Python and the homogenization toolbox Homtools. This has allowed us to better account for the nonlinear response of concrete. In studying the microstructure of HPC, we considered a two-dimensional representative volume element using the finite element method. Because of the random character of the arrangement of concrete's components, we utilized a stochastic method to generate the representative volume element (RVE) structure. Different constitutive models were used for the components of HPC: quartz sand-linear elastic, steel fibers-ideal elastic-plastic, and cement matrix-concrete damage plasticity. The numerical results obtained are compared with our own experimental data and those from the literature, and a good agreement can be observed.
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OBJECTIVE: Previous research has indicated that components of the metabolic syndrome (MetS), such as hyperglycemia and hypertension, are negatively associated with cognition. However, evidence that MetS itself is related to cognitive performance has been inconsistent. This longitudinal study investigates whether MetS or its components affect cognitive decline in aging men and whether any interaction with inflammation exists. METHODS: Over a mean of 4.4 years (SD ± 0.3), men aged 40-79 years from the multicenter European Male Ageing Study were recruited. Cognitive functioning was assessed using the Rey-Osterrieth Complex Figure (ROCF), the Camden Topographical Recognition Memory (CTRM) task, and the Digit Symbol Substitution Test (DSST). High-sensitivity C-reactive protein (hs-CRP) levels were measured using a chemiluminescent immunometric assay. RESULTS: Overall, 1,913 participants contributed data to the ROCF analyses and 1,965 subjects contributed to the CTRM and DSST analyses. In multiple regression models the presence of baseline MetS was not associated with cognitive decline over time (p > 0.05). However, logistic ordinal regressions indicated that high glucose levels were related to a greater risk of decline on the ROCF Copy (ß = -0.42, p < 0.05) and the DSST (ß = -0.39, p < 0.001). There was neither a main effect of hs-CRP levels nor an interaction effect of hs-CRP and MetS at baseline on cognitive decline. CONCLUSION: No evidence was found for a relationship between MetS or inflammation and cognitive decline in this sample of aging men. However, glycemia was negatively associated with visuoconstructional abilities and processing speed.
Subject(s)
Aging/psychology , Cognitive Dysfunction/metabolism , Hyperglycemia/metabolism , Hyperglycemia/psychology , Metabolic Syndrome/metabolism , Metabolic Syndrome/psychology , Adult , Aged , C-Reactive Protein/metabolism , Cognitive Dysfunction/complications , Geriatric Assessment , Humans , Hyperglycemia/complications , Inflammation/complications , Inflammation/metabolism , Longitudinal Studies , Male , Metabolic Syndrome/complications , Middle AgedABSTRACT
Background: frailty is associated with an increased risk of fragility fractures. Less is known, however, about the association between frailty and bone health. Methods: men aged 40-79 years were recruited from population registers in eight European centres for participation in the European Male Aging Study. Subjects completed a comprehensive assessment which included quantitative ultrasound (QUS) scan of the heel (Hologic-SAHARA) and in two centres, dual-energy bone densitometry (dual-energy x-ray absorptiometry, DXA). Frailty was defined based on an adaptation of Fried's phenotype criteria and a frailty index (FI) was constructed. The association between frailty and the QUS and DXA parameters was determined using linear regression, with adjustments for age, body mass index and centre. Results: in total, 3,231 subjects contributed data to the analysis. Using the Fried categorisation of frailty, pre-frail and frail men had significantly lower speed of sound (SOS), broadband ultrasound attenuation (BUA) and quantitative ultrasound index (QUI) compared to robust men (P< 0.05). Similar results were seen using the FI after categorisation into 'high', 'medium' and 'low' levels of frailty. Using the Fried categorisation, frail men had lower femoral neck bone mineral density (BMD) compared to robust men (P < 0.05), but not lower lumbar spine BMD. Using the FI categorisation, a 'high' level of frailty (FI > 0.35) was associated with lower lumbar spine BMD (P < 0.05) when compared to those with low (FI < 0.2), but not lower femoral neck BMD. When analysed as a continuous variable, higher FI was linked with lower SOS, BUA and QUI (P < 0.05). Conclusions: optimisation of bone health as well as prevention of falls should be considered as strategies to reduce fractures in frail older people.
Subject(s)
Bone Density , Bone and Bones/physiopathology , Frailty/physiopathology , Men's Health , Absorptiometry, Photon , Accidental Falls , Adult , Aged , Bone and Bones/diagnostic imaging , Europe , Fractures, Bone/etiology , Fractures, Bone/physiopathology , Fractures, Bone/prevention & control , Frailty/complications , Frailty/diagnostic imaging , Geriatric Assessment , Health Surveys , Humans , Linear Models , Male , Middle Aged , Risk Factors , UltrasonographyABSTRACT
Diversity in lifestyles and socioeconomic status among European populations, and recent socio-political and economic changes in transitional countries, may affect changes in adiposity. We aimed to determine whether change in the prevalence of obesity varies between the socio-politically transitional North-East European (Lódz, Poland; Szeged, Hungary; Tartu, Estonia), and the non-transitional Mediterranean (Santiago de Compostela, Spain; Florence, Italy) and North-West European (Leuven, Belgium; Malmö, Sweden; Manchester, UK) cities. This prospective observational cohort survey was performed between 2003 and 2005 at baseline and followed up between 2008 and 2010 of 3369 community-dwelling men aged 40-79 years. Main outcome measures in the present paper included waist circumference, body mass index and mid-upper arm muscle area. Baseline prevalence of waist circumference ≥ 102 cm and body mass index ≥ 30 kg/m2, respectively, were 39.0, 29.5 % in North-East European cities, 32.4, 21.9 % in Mediterranean cities, and 30.0, 20.1 % in North-West European cities. After median 4.3 years, men living in cities from transitional countries had mean gains in waist circumference (1.1 cm) and body mass index (0.2 kg/m2), which were greater than men in cities from non-transitional countries (P = 0.005). North-East European cities had greater gains in waist circumference (1.5 cm) than in Mediterranean cities (P < 0.001). Over 4.3 years, the prevalence of waist circumference ≥ 102 cm had increased by 13.1 % in North-East European cities, 5.8 % in the Mediterranean cities, 10.0 % in North-West European cities. Odds ratios (95 % confidence intervals), adjusted for lifestyle factors, for developing waist circumference ≥ 102 cm, compared with men from Mediterranean cities, were 2.3 (1.5-3.5) in North-East European cities and 1.6 (1.1-2.4) in North-West European cities, and 1.6 (1.2-2.1) in men living in cities from transitional, compared with cities from non-transitional countries. These regional differences in increased prevalence of waist circumference ≥ 102 cm were more pronounced in men aged 60-79 years than in those aged 40-59 years. Overall there was an increase in the prevalence of obesity (body mass index ≥ 30 kg/m2) over 4.3 years (between 5.3 and 6.1 %) with no significant regional differences at any age. Mid-upper arm muscle area declined during follow-up with the greatest decline among men from North-East European cities. In conclusion, increasing waist circumference is dissociated from change in body mass index and most rapid among men living in cities from transitional North-East European countries, presumably driven by economic and socio-political changes. Information on women would also be of value and it would be of interest to relate the changes in adiposity to dietary and other behavioural habits.
Subject(s)
Aging , Life Style , Obesity/epidemiology , Waist Circumference/physiology , Adiposity/physiology , Adult , Aged , Body Mass Index , Diet , Europe/epidemiology , Humans , Male , Middle Aged , Obesity/physiopathology , Prevalence , Prospective StudiesABSTRACT
PURPOSE: Although lower levels of vitamin D have been related to poor cognitive functioning and dementia in older adults, evidence from longitudinal investigations is inconsistent. The objective of this study was to determine whether 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)2D] levels are associated with specified measures of cognitive decline in ageing men. METHODS: The European Male Ageing Study (EMAS) followed 3369 men aged 40-79 over 4.4 years. 25(OH)D levels at baseline were measured by radioimmunoassay, and 1,25(OH)2D levels were obtained with liquid chromatography-tandem mass spectrometry. Visuoconstructional abilities, visual memory, and processing speed at baseline and follow-up were assessed using the Rey-Osterrieth Complex Figure Test (ROCF), Camden Topographical Recognition Memory (CTRM), and the Digit Symbol Substitution Test (DSST). RESULTS: Following attritions, a total of 2430 men with a mean (SD) age of 59.0 (10.6) were included in the analyses. At baseline, the mean 25(OH)D concentration was 64.6 (31.5) nmol/l, and mean 1,25(OH)2D level was 59.6 (16.6) pmol/l. In age-adjusted linear regression models, high 25(OH)D concentrations were associated with a smaller decline in the DSST (ß = 0.007, p = 0.020). Men with low 25(OH)D levels (<50 nmol/l) showed a greater decline in the CTRM compared to men with higher (≥75 nmol/l) levels (ß = -0.41, p = 0.035). However, these associations disappeared after adjusting for confounders such as depressive symptoms, BMI, and comorbidities. There was no indication of a relationship between 1,25(OH)2D and decline in cognitive subdomains. CONCLUSION: We found no evidence for an independent association between 25(OH)D or 1,25(OH)2D levels and visuoconstructional abilities, visual memory, or processing speed over on average 4.4 years in this sample of middle-aged and elderly European men.
Subject(s)
Aging/drug effects , Cognition/drug effects , Vitamin D/analogs & derivatives , Adult , Aged , Cognitive Dysfunction/blood , Cognitive Dysfunction/diagnosis , Follow-Up Studies , Health Behavior , Humans , Life Style , Male , Memory/drug effects , Middle Aged , Prospective Studies , Risk Factors , Surveys and Questionnaires , Vitamin D/administration & dosage , Vitamin D/blood , Vitamin D Deficiency/blood , Vitamin D Deficiency/complications , White PeopleABSTRACT
Objective. To investigate sperm DNA fragmentation and sperm functional maturity in men from infertile couples (IC) and men with testicular germ cell tumor (TGCT). Materials and Methods. Semen samples were collected from 312 IC men and 23 men with TGCT before unilateral orchiectomy and oncological treatment. The sperm chromatin dispersion test was performed to determine DNA fragmentation index (DFI) and the ability of sperm to bind with hyaluronan (HA) was assessed. Results. In comparison with the IC men, the men with TGCT had a higher percentage of sperm with fragmented DNA (median 28% versus 21%; p < 0.01) and a lower percentage of HA-bound sperm (24% versus 66%; p < 0.001). Normal results of both analyses were observed in 24% of IC men and 4% of men with TGCT. Negative Spearman's correlations were found between DFI and the percentage of HA-bound sperm in the whole group and in IC subjects and those with TGCT analyzed separately. Conclusions. Approximately 76% of IC men and 96% with TGCT awaiting orchiectomy demonstrated DNA fragmentation and/or sperm immaturity. We therefore recommend sperm banking after unilateral orchiectomy, but before irradiation and chemotherapy; the use of such a deposit appears to be a better strategy to obtain functionally efficient sperms.
Subject(s)
DNA Fragmentation , Hyaluronic Acid/chemistry , Infertility, Male/metabolism , Neoplasms, Germ Cell and Embryonal/metabolism , Spermatozoa/metabolism , Testicular Neoplasms/metabolism , Adult , Humans , Infertility, Male/pathology , Male , Middle Aged , Neoplasms, Germ Cell and Embryonal/pathology , Spermatozoa/pathology , Testicular Neoplasms/pathologyABSTRACT
CONTEXT: The androgen receptor (AR) gene exon 1 CAG repeat length has been proposed to be a determinant of between-individual variations in androgen action in target tissues, which might regulate phenotypic differences of human ageing. However, findings on its phenotypic effects are inconclusive. OBJECTIVE: To assess whether the AR CAG repeat length is associated with longitudinal changes in endpoints that are influenced by testosterone (T) levels in middle-aged and elderly European men. DESIGN: Multinational European observational prospective cohort study. PARTICIPANTS: A total of 1887 men (mean ± s.d. age: 63 ± 11 years; median follow up: 4.3 years) from centres of eight European countries comprised the analysis sample after exclusion of those with diagnosed diseases of the hypothalamic-pituitary-testicular (HPT) axis. MAIN OUTCOME MEASURES: Longitudinal associations between the AR CAG repeat and changes in androgen-sensitive endpoints (ASEs) and medical conditions were assessed using regression analysis adjusting for age and centre. The AR CAG repeat length was treated as both a continuous and a categorical (6-20; 21-23; 24-39 repeats) predictor. Additional analysis investigated whether results were independent of baseline T or oestradiol (E2) levels. RESULTS: The AR CAG repeat, when used as a continuous or a categorical predictor, was not associated with longitudinal changes in ASEs or medical conditions after adjustments. These results were independent of T and E2 levels. CONCLUSION: Within a 4-year time frame, variations in the AR CAG repeat do not contribute to the rate of phenotypic ageing, over and above, which might be associated with the age-related decline in T levels.
Subject(s)
Androgens/blood , Androgens/genetics , Independent Living/trends , Receptors, Androgen/blood , Receptors, Androgen/genetics , Trinucleotide Repeats/genetics , Aged , Biomarkers/blood , Cohort Studies , Europe/epidemiology , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Prospective Studies , Time FactorsABSTRACT
OBJECTIVE: In ageing men, the incidence and clinical significance of testosterone (T) decline accompanied by elevated luteinizing hormone (LH) are unclear. We describe the natural history, risk factors and clinical features associated with the development of biochemical primary hypogonadism (PHG, T < 10·5 nmol/l and LH>9·4U/l) in ageing men. DESIGN, PATIENTS AND MEASUREMENTS: A prospective observational cohort survey of 3,369 community-dwelling men aged 40-79 years, followed up for 4·3 years. Men were classified as incident (i) PHG (eugonadal [EUG, T ≥ 10·5 nmol/l] at baseline, PHG at follow-up), persistent (p) PHG (PHG at baseline and follow-up), pEUG (EUG at baseline and follow-up) and reversed (r) PHG (PHG at baseline, EUG at follow-up). Predictors and changes in clinical features associated with the development of PHG were analysed by regression models. RESULTS: Of 1,991 men comprising the analytical sample, 97·5% had pEUG, 1·1% iPHG, 1·1% pPHG and 0·3% rPHG. The incidence of PHG was 0·2%/year. Higher age (>70 years) [OR 12·48 (1·27-122·13), P = 0·030] and chronic illnesses [OR 4·24 (1·08-16·56); P = 0·038] predicted iPHG. Upon transition from EUG to PHG, erectile function, physical vigour and haemoglobin worsened significantly. Men with pPHG had decreased morning erections, sexual thoughts and haemoglobin with increased insulin resistance. CONCLUSIONS: Primary testicular failure in men is uncommon and predicted by old age and chronic illness. Some clinical features attributable to androgen deficiency, but not others, accompanied the T decline in men who developed biochemical PHG. Whether androgen replacement can improve sexual and/or physical function in elderly men with PHG merits further study.
Subject(s)
Aging/physiology , Hypogonadism/etiology , Adult , Age Factors , Aged , Aging/pathology , Androgens/deficiency , Chronic Disease , Cohort Studies , Humans , Hypogonadism/pathology , Male , Middle Aged , Prospective Studies , Risk Factors , Testosterone/deficiencyABSTRACT
CONTEXT: During aging, total testosterone (TT) declines and SHBG increases, resulting in a greater decrease in calculated free T (cFT). Currently, guidelines suggest using TT to diagnose androgen deficiency and to reserve cFT only for men with borderline TT. OBJECTIVE: Our objective was to investigate if either low cFT or low TT is more strongly associated with androgen-related clinical endpoints. METHODS: A total of 3334 community-dwelling men, aged 40-79 years, were included in this study. Differences in clinical variables between the referent group of men with both normal TT (≥10.5 nmol/liter) and normal cFT (≥220 pmol/liter) with those who had normal TT/low cFT, low TT/normal cFT, and low TT/low cFT were assessed by regression models adjusted for age, center, body mass index, and comorbidities. RESULTS: A total of 2641 men had normal TT (18.4 ± 5.5 [mean ± SD] nmol/liter)/normal cFT (326 ± 74 pmol/liter), 277 men had normal TT (14.2 ± 3.7)/low cFT (194 ± 23), 96 men had low TT (9.6 ± 0.7)/normal cFT (247 ± 20), and 320 men had low TT (7.8 ± 2.5)/low cFT (160 ± 55). Men with normal TT/low cFT were older and in poorer health. They had higher SHBG and LH and reported more sexual and physical symptoms, whereas hemoglobin and bone ultrasound parameters were lower compared to the referent group. Men with low TT/normal cFT were younger and more obese. They had lower SHBG, but LH was normal, whereas features of androgen deficiency were lacking. CONCLUSIONS: Low cFT, even in the presence of normal TT, is associated with androgen deficiency-related symptoms. Normal cFT, despite low TT, is not associated with cognate symptoms; therefore, cFT levels should be assessed in men with suspected hypogonadal symptoms.
Subject(s)
Hypogonadism/diagnosis , Testosterone/blood , Testosterone/deficiency , Adult , Aged , Asymptomatic Diseases , Cardiovascular Diseases/blood , Cardiovascular Diseases/complications , Cardiovascular Diseases/mortality , Cause of Death , Cohort Studies , Humans , Hypogonadism/blood , Hypogonadism/complications , Male , Metabolic Syndrome/blood , Metabolic Syndrome/complications , Metabolic Syndrome/mortality , Middle Aged , Sex Hormone-Binding Globulin/metabolismABSTRACT
BACKGROUND: The association between low levels of vitamin D and the occurrence of chronic widespread pain (CWP) remains unclear. The aim of our analysis was to determine the relationship between low vitamin D levels and the risk of developing CWP in a population sample of middle age and elderly men. METHODS: Three thousand three hundred sixty nine men aged 40-79 were recruited from 8 European centres for a longitudinal study of male ageing, the European Male Ageing Study. At baseline participants underwent assessment of lifestyle, health factors, physical characteristics and gave a fasting blood sample. The occurrence of pain was assessed at baseline and follow up (a mean of 4.3 years later) by shading painful sites on a body manikin. The presence of CWP was determined using the ACR criteria for fibromyalgia. Serum 25-hydroxyvitamin D (25-(OH) D) was assessed by radioimmunoassay. Logistic regression was used to determine the relationship between baseline vitamin D levels and the new occurrence of CWP. RESULTS: Two thousand three hundred thirteen men, mean age 58.8 years (SD = 10.6), had complete pain and vitamin data available and contributed to this analysis. 151 (6.5%) developed new CWP at follow up and 577 (24.9%) were pain free at both time points, the comparator group. After adjustment for age and centre, physical performance and number of comorbidities, compared to those in upper quintile of 25-(OH) D ( ≥36.3 ng/mL), those in the lowest quintile (<15.6 ng/mL) were more likely to develop CWP (Odds Ratio [OR] = 1.93; 95% CI = 1.0-3.6). Further adjustment for BMI (OR = 1.67; 95% CI = 0.93-3.02) or depression (OR = 1.77; 95% CI = 0.98-3.21), however rendered the association non-significant. CONCLUSIONS: Low vitamin D is linked with the new occurrence of CWP, although this may be explained by underlying adverse health factors, particularly obesity and depression.
Subject(s)
Aging/blood , Chronic Pain/blood , Chronic Pain/epidemiology , Pain Measurement/trends , Vitamin D/blood , Adult , Aged , Aging/pathology , Biomarkers/blood , Chronic Pain/diagnosis , Europe/epidemiology , Follow-Up Studies , Humans , Longitudinal Studies , Male , Middle Aged , Pain Measurement/methods , Risk FactorsABSTRACT
BACKGROUND: we hypothesised that chronic widespread pain (CWP), by acting as a potential stressor, may predispose to the development of, or worsening, frailty. SETTING: longitudinal analysis within the European Male Ageing Study (EMAS). PARTICIPANTS: a total of 2,736 community-dwelling men aged 40-79. METHODS: subjects completed a pain questionnaire and shaded a manikin, with the presence of CWP defined using the American College of Rheumatology criteria. Physical activity, smoking, alcohol consumption and depression were measured. Repeat assessments took place a median of 4.3 years later. A frailty index (FI) was used, with frail defined as an FI >0.35. The association between CWP at baseline and the new occurrence of frailty was examined using logistic regression; the association between CWP at baseline and change in FI was examined using negative binomial regression. RESULTS: at baseline, 218 (8.3%) men reported CWP. Of the 2,631 men who were defined as non-frail at baseline, 112 (4.3%) were frail at follow-up; their mean FI was 0.12 (SD 0.1) at baseline and 0.15 (SD 0.1) at follow-up, with a mean change of 0.03 (SD 0.08) P ≤ 0.001. Among men who were non-frail at baseline, those with CWP were significantly more likely to develop frailty. After adjustment for age and centre, compared with those with no pain, those with CWP at baseline had a 70% higher FI at follow-up; these associations remained significant after further adjustment for smoking, body mass index, depression, physical activity and FI at baseline. CONCLUSION: the presence of CWP is associated with an increased risk of frailty in older European men.
Subject(s)
Aging , Chronic Pain/epidemiology , Frail Elderly , Adult , Age Factors , Aged , Chronic Pain/diagnosis , Comorbidity , Disease Progression , Europe/epidemiology , Geriatric Assessment , Humans , Incidence , Logistic Models , Longitudinal Studies , Male , Middle Aged , Odds Ratio , Pain Measurement , Prognosis , Prospective Studies , Risk Factors , Sex Factors , Surveys and Questionnaires , Time FactorsABSTRACT
INTRODUCTION: In patients with Y-chromosome in the karyotype, partial gonadal dysgenesis and disorders of male reproductive sex organs development are usually resected in childhood because of the high risk of germ cell tumours (GCT). In patients with Y-chromosome, complete gonadal dysgenesis and female genitalia gonadectomy is performed markedly later. However, due to the relatively low number of adult patients with preserved dysgenetic gonads, the true risk of neoplasm is unknown. The aim of the study was to evaluate the prevalence of neoplasia in dysgenetic gonads of children and adults with Y-chromosome in a retrospective study. MATERIAL AND METHODS: A review of medical documentation of 94 patients with disorders of sex development (DSD), Y-chromosome and gonadal dysgenesis (GD), aged 1.2-32 years (47 prepubertal, 1.2-10 years; 47 pubertal/adult, 13-32 years), was conducted. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone were determined. Bilateral gonadectomy was performed in 73.4% of patients, and unilateral gonadectomy with biopsy of the contralateral gonad in 26.4%. All gonadal tissues were subjected to immunohistochemical evaluation with antibodies against PLAP and OCT3/4 (markers of malignant germ cells, but also foetal multipotent germ cells), while gonads of prepubertal patients were examined by c-KIT, as well. RESULTS: Streak gonads were identified on both sides (complete GD) in 30.8%, a streak gonad on one side and an underdeveloped testis on the other (asymmetric GD) in 38.3%, and underdeveloped testicular structure on both sides (partial GD) in 30.8% of cases. Germ cell neoplasia was found in 53.2% of patients (51.1% in children, 55.3% in pubertal/adults). Invasive GCT were identified in 11.7% of cases, of which 90.9% were in pubertal/adult patients. Other neoplastic lesions included gonadoblastoma (16% prevalence) and testicular carcinoma in situ (25.5%). In younger patients FSH serum levels were increased in 81% of cases (mean 2.82 ± 2.18 IU/L), while LH in 58% (mean 1.82 ± 1.69 IU/L). Hypergonadotropic hypogonadism was diagnosed in most of the pubertal/ /adult patients (mean FSH 54.2 ± 23.3 IU/L, mean LH 21.7 ± 12.1 IU/L, mean testosterone 5.5 ± 4.5 nmol/L). CONCLUSIONS: Dysgenetic gonads in patients with Y chromosome have a high risk of germ cell neoplasia (ca. 50%). If they are preserved until puberty/early adulthood, they may develop overt, invasive GCT. The gonads also have poor hormonal activity (hypergonadotropic hypogonadism) in most of the pubertal/adult patients. Each of these cases must be considered individually and a decision to remove the gonad or not should be based on the comprehensive analysis of the phenotype by a multidisciplinary team of specialists in consultation with the patient and the parents. If dysgenetic gonads are not resected in childhood, these patients need careful ongoing follow-up examination, including biopsy and histopathological evaluation.
Subject(s)
Gonadal Dysgenesis/complications , Gonadal Dysgenesis/pathology , Testicular Neoplasms/complications , Testis/pathology , Adolescent , Adult , Child , Child, Preschool , Gonadotropins/blood , Humans , Infant , Male , Retrospective Studies , Risk Factors , Testicular Neoplasms/epidemiology , Testosterone/bloodABSTRACT
BACKGROUND: low bone mineral density measured by dual-energy x-ray absorptiometry is associated with increased mortality. The relationship between other skeletal phenotypes and mortality is unclear. The aim of this study was to determine the relationship between quantitative heel ultrasound parameters and mortality in a cohort of European men. METHODS: men aged 40-79 years were recruited for participation in a prospective study of male ageing: the European Male Ageing Study (EMAS). At baseline, subjects attended for quantitative ultrasound (QUS) of the heel (Hologic-SAHARA) and completed questionnaires on lifestyle factors and co-morbidities. Height and weight were measured. After a median of 4.3 years, subjects were invited to attend a follow-up assessment, and reasons for non-participation, including death, were recorded. The relationship between QUS parameters (broadband ultrasound attenuation [BUA] and speed of sound [SOS]) and mortality was assessed using Cox proportional hazards model. RESULTS: from a total of 3,244 men (mean age 59.8, standard deviation [SD] 10.8 years), 185 (5.7%) died during the follow-up period. After adjusting for age, centre, body mass index, physical activity, current smoking, number of co-morbidities and general health, each SD decrease in BUA was associated with a 20% higher risk of mortality (hazard ratio [HR] per SD = 1.2; 95% confidence interval [CI] = 1.0-1.4). Compared with those in higher quintiles (2nd-5th), those in the lowest quintile of BUA and SOS had a greater mortality risk (BUA: HR = 1.6; 95% CI = 1.1-2.3 and SOS: HR = 1.6; 95% CI = 1.2-2.2). CONCLUSION: lower heel ultrasound parameters are associated with increased mortality in European men.
Subject(s)
Aging , Health Status , Heel/diagnostic imaging , Adult , Age Factors , Aged , Body Mass Index , Cause of Death , Comorbidity , Europe , Geriatric Assessment , Humans , Life Style , Male , Middle Aged , Predictive Value of Tests , Prognosis , Proportional Hazards Models , Prospective Studies , Risk Assessment , Risk Factors , Surveys and Questionnaires , Time Factors , UltrasonographyABSTRACT
CONTEXT: Secondary hypogonadism is common in aging men; its natural history and predisposing factors are unclear. OBJECTIVES: The objectives were 1) to identify factors that predispose eugonadal men (T ≥ 10.5 nmol/L) to develop biochemical secondary hypogonadism (T < 10.5 nmol/L; LH ≤ 9.4 U/L) and secondary hypogonadal men to recover to eugonadism; and 2) to characterize clinical features associated with these transitions. DESIGN: The study was designed as a prospective observational general population cohort survey. SETTING: The setting was clinical research centers. PARTICIPANTS: The participants were 3369 community-dwelling men aged 40-79 years in eight European centers. INTERVENTION: Interventions included observational follow-up of 4.3 years. MAIN OUTCOME MEASURE: Subjects were categorized according to change/no change in biochemical gonadal status during follow-up as follows: persistent eugonadal (n = 1909), incident secondary hypogonadal (n = 140), persistent secondary hypogonadal (n = 123), and recovered from secondary hypogonadism to eugonadism (n = 96). Baseline predictors and changes in clinical features associated with incident secondary hypogonadism and recovery from secondary hypogonadism were analyzed by regression models. RESULTS: The incidence of secondary hypogonadism was 155.9/10 000/year, whereas 42.9% of men with secondary hypogonadism recovered to eugonadism. Incident secondary hypogonadism was predicted by obesity (body mass index ≥ 30 kg/m(2); odds ratio [OR] = 2.86 [95% confidence interval, 1.67; 4.90]; P < .0001), weight gain (OR = 1.79 [1.15; 2.80]; P = .011), and increased waist circumference (OR = 1.73 [1.07; 2.81], P = .026; and OR = 2.64 [1.66; 4.21], P < .0001, for waist circumference 94-102 and ≥102 cm, respectively). Incident secondary hypogonadal men experienced new/worsening sexual symptoms (low libido, erectile dysfunction, and infrequent spontaneous erections). Recovery from secondary hypogonadism was predicted by nonobesity (OR = 2.28 [1.21; 4.31]; P = .011), weight loss (OR = 2.24 [1.04; 4.85]; P = .042), normal waist circumference (OR = 1.93 [1.01; 3.70]; P = .048), younger age (< 60 y; OR = 2.32 [1.12; 4.82]; P = .024), and higher education (OR = 2.11 [1.05; 4.26]; P = .037), but symptoms did not show significant concurrent improvement. CONCLUSION: Obesity-related metabolic and lifestyle factors predispose older men to the development of secondary hypogonadism, which is frequently reversible with weight loss.
Subject(s)
Aging/physiology , Hypogonadism/etiology , Hypogonadism/rehabilitation , Adult , Aged , Cohort Studies , Follow-Up Studies , Humans , Hypogonadism/epidemiology , Life Style , Male , Middle Aged , Obesity/complications , Obesity/epidemiology , Recovery of Function/physiology , Sexual Dysfunction, Physiological/epidemiology , Sexual Dysfunction, Physiological/etiology , Waist Circumference/physiology , Weight Loss/physiologyABSTRACT
Follicle-stimulating hormone (FSH) and triiodothyronine (T3) are known regulatory factors of spermatogenesis initiation. Hyperstimulation of both hormones evokes regressional changes in connexin 43 expression and the seminiferous epithelium in young rats during testicular maturation. However, separate treatments with T3 reduce Sertoli cell number, which seems to be closely connected with the maturation of connexin 43 gap junctions. FSH elevates Sertoli cell number and function, but this effect may take place regardless of the presence of connexin 43-dependent intercellular communication. The aim of the study was to evaluate the later effects of such treatments. Newborn, male Wistar rats were divided randomly into experimental groups receiving daily subcutaneous injections of either 7.5 IU/animal FSH, or 100 mg/kg b.w. T3, or both substances or the same volume of vehicle (control group) until day 15 of life. The animals were sacrificed on day 50. Morphometric analysis and immunohistochemical reactions were performed using antibodies against Vimentin, Proliferating Cell Nuclear Antigen and Connexin 43 in the testis. Sertoli cell count, efficiency of spermatogenesis, and hormonal pattern were examined. Disturbances in the connexin 43 expression reduced the number of Sertoli cells, the efficiency of spermatogenesis and impaired endocrine function of testes in adult rats treated with FSH and T3 during puberty. Stimulation with FSH alone increased Sertoli cell number, but was associated with a negative effect on cell-to-cell connexin 43-dependent communication, with a consequential reduction of spermatogenesis efficiency. J. Exp. Zool. 323A: 256-265, 2015. © 2015 Wiley Periodicals, Inc.