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1.
Nature ; 630(8017): 720-727, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38839949

RESUMO

Spermatozoa harbour a complex and environment-sensitive pool of small non-coding RNAs (sncRNAs)1, which influences offspring development and adult phenotypes1-7. Whether spermatozoa in the epididymis are directly susceptible to environmental cues is not fully understood8. Here we used two distinct paradigms of preconception acute high-fat diet to dissect epididymal versus testicular contributions to the sperm sncRNA pool and offspring health. We show that epididymal spermatozoa, but not developing germ cells, are sensitive to the environment and identify mitochondrial tRNAs (mt-tRNAs) and their fragments (mt-tsRNAs) as sperm-borne factors. In humans, mt-tsRNAs in spermatozoa correlate with body mass index, and paternal overweight at conception doubles offspring obesity risk and compromises metabolic health. Sperm sncRNA sequencing of mice mutant for genes involved in mitochondrial function, and metabolic phenotyping of their wild-type offspring, suggest that the upregulation of mt-tsRNAs is downstream of mitochondrial dysfunction. Single-embryo transcriptomics of genetically hybrid two-cell embryos demonstrated sperm-to-oocyte transfer of mt-tRNAs at fertilization and suggested their involvement in the control of early-embryo transcription. Our study supports the importance of paternal health at conception for offspring metabolism, shows that mt-tRNAs are diet-induced and sperm-borne and demonstrates, in a physiological setting, father-to-offspring transfer of sperm mitochondrial RNAs at fertilization.


Assuntos
Dieta Hiperlipídica , Epigênese Genética , Mitocôndrias , RNA Mitocondrial , Espermatozoides , Animais , Feminino , Humanos , Masculino , Camundongos , Dieta Hiperlipídica/efeitos adversos , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Epididimo/citologia , Epigênese Genética/genética , Fertilização/genética , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/genética , Obesidade/genética , Obesidade/metabolismo , Obesidade/etiologia , Oócitos/metabolismo , Sobrepeso/genética , Sobrepeso/metabolismo , Herança Paterna/genética , RNA Mitocondrial/genética , RNA Mitocondrial/metabolismo , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , Espermatozoides/metabolismo , Testículo/citologia , Regulação da Expressão Gênica no Desenvolvimento , Perfilação da Expressão Gênica , Transcrição Gênica , Índice de Massa Corporal
2.
Hum Reprod ; 31(5): 947-57, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26936886

RESUMO

STUDY QUESTION: Is the Leydig cell function of young European men associated with semen quality? SUMMARY ANSWER: Compensated reduction in Leydig cell function, defined as increased LH concentration combined with adequate testosterone production is associated with lower semen quality. WHAT IS ALREADY KNOWN: Semen quality of young European men shows a heterogeneous pattern. Many have sperm counts below and in the lower WHO reference where there nevertheless is a significant risk of subfecundity. Little is known about differences in Leydig cell function between men with semen quality below and within the WHO reference range. STUDY DESIGN, SIZE AND DURATION: A coordinated, cross-sectional population-based study of 8182 men undertaken in 1996-2010. PARTICIPANTS, SETTING AND METHOD: Young men (median age 19.1 years) were investigated in centres in Denmark, Estonia, Finland, Germany Latvia, Lithuania, and Spain. The men originated from the general populations, all were young, almost all were unaware of their fecundity and each provided a semen and blood sample. Associations between semen parameters and serum levels of testosterone and luteinising hormone (LH), calculated free testosterone, and ratios between serum testosterone and LH were determined. MAIN RESULT AND ROLE OF CHANCE: Serum testosterone levels were not associated with sperm concentrations, total sperm counts, or percentage of motile or morphologically normal spermatozoa. There was an inverse association between the semen parameters and serum LH levels, and accordingly a positive association to testosterone/LH ratio and calculated-free-testosterone/LH ratio. LIMITATIONS, REASON FOR CAUTION: The size of the study mitigates the intra-individual variability concern. The distinction between different sub-categories of sperm motility and sperm morphology is subjective despite training. However, inter-observer variation would tend towards non-differential misclassification and would decrease the likelihood of detecting associations between reproductive hormone levels and semen variables, suggesting that the presented associations might in reality be even stronger than shown. Although we adjusted for confounders, we cannot of course exclude that our results can be skewed by selection bias or residual confounding. WIDER IMPLICATIONS OF THE FINDINGS: Compensated reduction in Leydig cell function, defined as increased LH concentration combined with adequate testosterone production is associated with lower semen quality. This is apparent even within the WHO reference range of semen quality. It is unknown whether impaired Leydig cell function in young men may confer an increased risk of acquired testosterone deficiency later in life. STUDY FUNDING/COMPETING INTERESTS: Support from The Research Fund of Rigshospitalet (grant no. R42-A1326) to N.J. made this study possible. The background studies of young men have been supported economically by several grants. ITALIC! Denmark: The European Union (contract numbers BMH4-CT96-0314, QLK4-CT-1999-01422, QLK4-CT-2002-00603 and most recently FP7/2007-2013, DEER Grant agreement no. 212844), The Danish Research Council (grants nos. 9700833 2107-05-0006), The Danish Agency for Science, Technology and Innovation (Grant no. 271070678), Rigshospitalet (Grant no. 961506336), The University of Copenhagen (Grant no. 211-0357/07-3012), The Danish Ministry of Health and the Danish Environmental Protection Agency, A.P. Møller and wife Chastine McKinney Møllers foundation, and Svend Andersens Foundation. ITALIC! Finland: European Union (contract numbers BMH4-CT96-0314, QLK4-CT-1999-01422, QLK4-CT- 2002-00603 and most recently FP7/2008-2012, DEER Grant agreement no. 212844), The Academy of Finland, Turku University Hospital Funds, Sigrid Juselius Foundation. ITALIC! Estonia, Latvia and Lithuania: European Union (QLRT-2001-02911), the Estonian Science Foundation, grant number 2991, Lithuanian Foundation for Research, Organon Agencies B.V. and the Danish Research Council, grant no. 9700833. ITALIC! Germany: European Union (contract numbers QLK4-CT-2002-00603). ITALIC! Spain: European Commission QLK4-1999-01422. M.F. received support from the Spanish Ministry of Science and Innovation (Program Ramon y Cajal). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. None of the authors have any competing interests to declare.


Assuntos
Células Intersticiais do Testículo/fisiologia , Análise do Sêmen , Adulto , Estudos Transversais , Europa (Continente) , Fertilidade , Humanos , Hormônio Luteinizante/sangue , Masculino , Estudos Prospectivos , Valores de Referência , Testosterona/sangue
3.
Int J Androl ; 35(3): 283-93, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22150420

RESUMO

In animal studies, exposure to dioxins has been associated with disrupted development of the male reproductive system, including testicular maldescent. Some polychlorinated biphenyls (PCBs) have also dioxin-like effects. In addition, one previous case-control study has reported an association between congenital cryptorchidism and colostrum PCB levels. We performed a case-control study to evaluate whether congenital cryptorchidism in boys was associated with increased levels of dioxins or PCBs in placenta reflecting foetal exposure. In addition, associations between placenta levels of these chemicals and reproductive hormone levels in boys at 3 months were studied. Placentas were collected in a Danish-Finnish joint prospective cohort study on cryptorchidism (1997-2001). The boys were examined for cryptorchidism at birth and at 3 months. Altogether, 280 placentas [112 Finnish (56 cases, 56 controls) and 168 Danish (39 cases, 129 controls)] were analysed for 17 toxic polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 37 PCBs (including 12 dioxin-like PCBs). Infant serum samples taken at 3 months were analysed for reproductive hormones. No significant differences between cases and controls were observed in either country in dioxin WHO-TEq levels (median 9.78 vs. 8.47 pg/g fat, respectively, in Finland, and 11.75 vs. 10.88 pg/g fat in Denmark) or PCB WHO-TEq levels (median 2.12 vs. 2.15 pg/g fat in Finland, 2.34 vs. 2.10 pg/g fat in Denmark) or total-TEq levels (median 11.66 vs. 10.58 pg/g fat in Finland, 13.94 vs. 13.00 pg/g fat in Denmark). Placenta WHO-TEq levels of dioxins were not associated with infant reproductive hormone levels at 3 months. In Finland, PCB WHO-TEq levels in placenta associated positively with infant LH levels. WHO-TEq levels of dioxins and PCBs and total-TEq levels were higher in Danish than Finnish samples. In conclusion, no association between placenta levels of dioxins or PCBs and congenital cryptorchidism was found. Significant country differences in chemical levels were observed.


Assuntos
Criptorquidismo/etiologia , Dioxinas/análise , Placenta/química , Bifenilos Policlorados/análise , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Dinamarca , Feminino , Finlândia , Humanos , Recém-Nascido , Hormônio Luteinizante/sangue , Masculino , Gravidez
4.
Int J Androl ; 35(3): 294-302, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22519522

RESUMO

During the past four decades, there has been an increase in the incidence rate of male reproductive disorders in some, but not all, Western countries. The observed increase in the prevalence of male reproductive disorders is suspected to be ascribable to environmental factors as the increase has been too rapid to be explained by genetics alone. To study the association between complex chemical exposures of humans and congenital cryptorchidism, the most common malformation of the male genitalia, we measured 121 environmental chemicals with suspected or known endocrine disrupting properties in 130 breast milk samples from Danish and Finnish mothers. Half the newborns were healthy controls, whereas the other half was boys with congenital cryptorchidism. The measured chemicals included polychlorinated biphenyls (PCBs), polybrominated diphenyl-ethers, dioxins (OCDD/PCDFs), phthalates, polybrominated biphenyls and organochlorine pesticides. Computational analysis of the data was performed using logistic regression and three multivariate machine learning classifiers. Furthermore, we performed systems biology analysis to explore the chemical influence on a molecular level. After correction for multiple testing, exposure to nine chemicals was significantly different between the cases and controls in the Danish cohort, but not in the Finnish cohort. The multivariate analysis indicated that Danish samples exhibited a stronger correlation between chemical exposure patterns in breast milk and cryptorchidism than Finnish samples. Moreover, PCBs were indicated as having a protective effect within the Danish cohort, which was supported by molecular data recovered through systems biology. Our results lend further support to the hypothesis that the mixture of environmental chemicals may contribute to observed adverse trends in male reproductive health.


Assuntos
Criptorquidismo/epidemiologia , Leite Humano/química , Inteligência Artificial , Dinamarca/epidemiologia , Dioxinas/análise , Poluentes Ambientais/análise , Feminino , Finlândia/epidemiologia , Éteres Difenil Halogenados/análise , Humanos , Modelos Logísticos , Masculino , Bifenilos Policlorados/análise , Biologia de Sistemas
5.
Int J Androl ; 34(4 Pt 2): e37-48, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21366607

RESUMO

Impaired semen quality and testicular cancer may be linked through a testicular dysgenesis syndrome of foetal origin. The incidence of testis cancer has been shown to increase among Finnish men, whereas there is no recent publication describing temporal trends in semen quality. Therefore, we carried out a prospective semen quality study and a registry study of testis cancer incidence among Finnish men to explore recent trends. A total of 858 men were investigated in the semen quality study during 1998-2006. Median sperm concentrations were 67 (95% CI 57-80) million/mL, 60 (51-71) and 48 (39-60) for birth cohorts 1979-81, 1982-83 and 1987; total sperm counts 227 (189-272) million, 202 (170-240) and 165 (132-207); total number of morphologically normal spermatozoa 18 (14-23) million, 15 (12-19) and 11 (8-15). Men aged 10-59 years at the time of diagnosis with testicular cancer during 1954-2008 were included in the registry study, which confirmed the increasing incidence of testicular cancer in recent cohorts. These simultaneous and rapidly occurring adverse trends suggest that the underlying causes are environmental and, as such, preventable. Our findings necessitate not only further surveillance of male reproductive health but also research to detect and remove the underlying factors.


Assuntos
Sêmen/citologia , Neoplasias Testiculares/epidemiologia , Adolescente , Adulto , Criança , Finlândia/epidemiologia , Disgenesia Gonadal/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/anormalidades , Espermatozoides/patologia
6.
Int J Androl ; 33(2): 270-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19780864

RESUMO

Recent reports have confirmed a worldwide increasing trend of testicular cancer incidence, and a conspicuously high prevalence of this disease and other male reproductive disorders, including cryptorchidism and hypospadias, in Denmark. In contrast, Finland, a similarly industrialized Nordic country, exhibits much lower incidences of these disorders. The reasons behind the observed trends are unexplained, but environmental endocrine disrupting chemicals (EDCs) that affect foetal testis development are probably involved. Levels of persistent chemicals in breast milk can be considered a proxy for exposure of the foetus to such agents. Therefore, we undertook a comprehensive ecological study of 121 EDCs, including the persistent compounds dioxins, polychlorinated biphenyls (PCBs), pesticides and flame retardants, and non-persistent phthalates, in 68 breast milk samples from Denmark and Finland to compare exposure of mothers to this environmental mixture of EDCs. Using sophisticated, bioinformatic tools in our analysis, we reveal, for the first time, distinct country-specific chemical signatures of EDCs with Danes having generally higher exposure than Finns to persistent bioaccumulative chemicals, whereas there was no country-specific pattern with regard to the non-persistent phthalates. Importantly, EDC levels, including some dioxins, PCBs and some pesticides (hexachlorobenzene and dieldrin) were significantly higher in Denmark than in Finland. As these classes of EDCs have been implicated in testicular cancer or in adversely affecting development of the foetal testis in humans and animals, our findings reinforce the view that environmental exposure to EDCs may explain some of the temporal and between-country differences in incidence of male reproductive disorders.


Assuntos
Dioxinas/análise , Disruptores Endócrinos/análise , Exposição Ambiental , Poluentes Ambientais/análise , Hidrocarbonetos Clorados/análise , Exposição Materna , Leite Humano/química , Bifenilos Policlorados/análise , Dinamarca , Dieldrin/análise , Dioxinas/toxicidade , Poluentes Ambientais/toxicidade , Feminino , Finlândia , Retardadores de Chama/análise , Hexaclorobenzeno/análise , Humanos , Hidrocarbonetos Clorados/toxicidade , Masculino , Praguicidas/análise , Neoplasias Testiculares/induzido quimicamente , Testículo/efeitos dos fármacos , Testículo/embriologia
7.
Andrology ; 7(1): 15-23, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30251363

RESUMO

BACKGROUND: Finnish men used to have higher semen quality than Danish men. However, recent studies showed that semen quality in Finland has declined, but it has been relatively stable in Denmark. OBJECTIVE: This study aimed to compare new data on semen quality of the young Finnish men to that of Danish men. MATERIALS AND METHODS: In this cross-sectional study, 18- to 19-year-old men residing in Turku, Finland and Copenhagen, Denmark, were invited to participate in 2008-2011. Each man filled in a questionnaire, provided one semen sample and underwent andrological examination. Semen samples were analyzed according to WHO. Multiway ANOVA was used to adjust semen variables for duration of sexual abstinence and age (and time from ejaculation to the start of semen analysis for sperm motility). RESULTS: Altogether 287 Finnish men and 873 Danish men participated in the study. The adjusted median sperm concentrations were 49 and 47 million/mL for Finnish and Danish men, respectively (p = 0.48). The adjusted median total sperm counts were 148 million in Finland and 146 million in Denmark (p = 0.87). The adjusted median percentages of morphologically normal spermatozoa were 6.9% in Finland and 6.5% in Denmark, p = 0.27. Finnish men had higher adjusted median percentages of motile spermatozoa (A+B+C) than Danish men (80% vs. 69%, p < 0.001). The proportion of men who had low semen quality (sperm concentration, percentage of morphologically normal spermatozoa or percentage of progressively motile spermatozoa below WHO reference limits) was lower in Finland (25.4%) than in Denmark (34.6%), p = 0.004. DISCUSSION: Considerable percentage of men in both countries had low semen quality. The deteriorating semen quality in Finland may result in decreasing fecundity, which is a cause of concern. CONCLUSION: The formerly high semen quality in Finland has converged to the lower Danish levels. Our findings demonstrate the importance of continuing surveillance of semen quality.


Assuntos
Análise do Sêmen , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Adolescente , Estudos Transversais , Dinamarca , Finlândia , Humanos , Infertilidade Masculina , Masculino , Inquéritos e Questionários , Adulto Jovem
8.
Phys Med Biol ; 52(5): 1221-36, 2007 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-17301450

RESUMO

As the use of radiofrequency (RF) electromagnetic (EM) fields has increased along with increased use of wireless communication, the possible related health risks have also been widely discussed. One safety aspect is the interaction of medical implants and RF devices like mobile phones. In the literature, effects on active implants like pacemakers have been discussed but the studies of passive metallic (i.e. conductive) implants are rare. However, some studies have shown that the EM power absorption in tissues may be enhanced due to metallic implants. In this study, the effect of authentic passive metallic implants in the head region was examined. A half-wave dipole antenna was used as an exposure source and the specific absorption rate (SAR, W kg(-1)) in the near field was studied numerically. The idea was to model the presumably worst cases of most common implants in an accurate MRI-based phantom. As exposure frequencies GSM (900 and 1800 MHz) and UMTS (2450 MHz) regions were considered. The implants studied were skull plates, fixtures, bone plates and ear rings. The results indicate that some of the implants, under very rare exposure conditions, may cause a notable enhancement in peak mass averaged SAR.


Assuntos
Placas Ósseas , Exposição Ambiental/análise , Cabeça/fisiologia , Metais , Micro-Ondas , Modelos Biológicos , Radiometria/métodos , Carga Corporal (Radioterapia) , Simulação por Computador , Especificidade de Órgãos , Doses de Radiação , Eficiência Biológica Relativa
9.
J Steroid Biochem Mol Biol ; 102(1-5): 184-6, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17049842

RESUMO

Regulation of testicular descent is hormonally regulated, but the reasons for maldescent remain unknown in most cases. The main regulatory hormones are Leydig cell-derived testosterone and insulin-like factor 3 (INSL3). Luteinizing hormone (LH) stimulates the secretion of these hormones, but the secretory responses to LH are different: INSL3 secretion increases slowly and may reflect the LH dependent differentiated status of Leydig cells, whereas testosterone response to LH is immediate. Testosterone contributes to the involution of the suspensory ligament and to the inguinoscrotal phase of the descent, while INSL3 acts mainly in transabdominal descent by stimulating the growth of the gubernaculum. INSL3 acts through a G-protein coupled receptor LGR8. In the absence of either INSL3 or LGR8 mice remain cryptorchid. In humans only few INSL3 mutations have been described, whereas LGR8 mutations may cause some cases of undescended testis. Similarly, androgen insensitivity or androgen deficiency can cause cryptorchidism. Estrogens have been shown to down regulate INSL3 and thereby cause maldescent. Thus, a reduced androgen-estrogen ratio may disturb testicular descent. Environmental effects changing the ratio can thereby influence cryptorchidism rate. Estrogens and anti-androgens cause cryptorchidism in experimental animals. In our cohort study we found higher LH/testosterone ratios in 3-month-old cryptorchid boys than in normal control boys, suggesting that cryptorchid testes are not cabable of normal hormone secretion without increased gonadotropin drive. This may be either the cause or consequence of cryptorchidism. Some phthalates act as anti-androgens and cause cryptorchidism in rodents. In our human material we found an association of a high phthalate exposure with a high LH/testosterone ratio. We hypothesize that an exposure to a mixture of chemicals with anti-androgenic or estrogenic properties (either their own activity or their effect on androgen-estrogen ratio) may be involved in cryptorchidism.


Assuntos
Meio Ambiente , Hormônios/farmacologia , Testículo/crescimento & desenvolvimento , Animais , Humanos , Masculino , Testículo/efeitos dos fármacos
10.
Chemosphere ; 62(3): 390-5, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16005046

RESUMO

The enantiomeric ratios (ER) of alpha-HCH and o,p'-DDT ((+)-isomer concentration/(-)-isomer concentration) and o,p'-DDD (first eluting enantiomer/second enantiomer) were investigated in 112 human placentas from Finnish boys collected 1997-2001. Both o,p'-DDD and alpha-HCH showed changes in their ER depending on the total concentration of the compound in the sample. Their ERs are approaching a value close to racemic mixture (ER=1) at high concentrations. At low concentrations they often differ from 1. The relationship between concentration and ER is clearly identified and it has been shown that it is not affected by analytical uncertainty. This relationship appears to be important for assessing tissue- and species-specific exposure and risk and it may indicate whether net uptake or metabolic activity is dominant in exposure for the resulting exposure of the enantiomers.


Assuntos
DDT/análise , Exposição Ambiental/análise , Poluentes Ambientais/análise , Hexaclorocicloexano/análise , Placenta/química , Monitoramento Ambiental , Finlândia , Humanos , Técnicas In Vitro , Estudos Longitudinais , Estereoisomerismo
11.
Environ Pollut ; 218: 728-738, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27521295

RESUMO

The present study compares concentrations and chemical profiles of an extended range of persistent organic pollutants (dioxins, polychlorobiphenyls, brominated flame retardants and organochlorine pesticides) in breast milk samples from French (n = 96), Danish (n = 438) and Finnish (n = 22) women. Median exposure levels observed in French women (WHO-TEQ2005 PCDD/F = 6.1 pg/g l.w., WHO-TEQ2005 dl-PCB = 4.3 pg/g l.w., sum of 6 ndl-PCB = 85.2 ng/g l.w., sum of 7 i-PBDE = 1.5 ng/g l.w.) appeared overall lower than in Danish and Finnish women for all examined POPs, except for α-HBCD (2-fold higher level at 0.6 ng/g l.w.). Furthermore, the observed exposure levels of dioxins and PCBs were higher in Danish women (WHO-TEQ2005 PCDD/F = 13.2 pg/g l.w., WHO-TEQ2005 dl-PCB = 6.6 pg/g l.w., sum of 6 ndl-PCB = 162.8 ng/g l.w.) compared to Finnish women (WHO-TEQ2005 PCDD/F = 9.0 pg/g l.w., WHO-TEQ2005 dl-PCB = 4.6 pg/g l.w., sum of 6 ndl-PCB = 104.0 ng/g l.w.), whereas the concentrations of PBDEs were similar for Danish and Finnish women (sum of 7 i-PBDE = 4.9 and 5.2 ng/g l.w. respectively). The organochlorine (OC) pesticide contamination profile, determined in a subset of French samples, was dominated by p,p'-DDE (56.6%), followed by ß-HCH (14.2%), HCB (9.7%) and dieldrin (5.2%), while other compounds were only minor contributors (<5%). The three countries appeared to be discriminated by the observed contamination patterns of the PCDD/F versus PCB, and the 1,2,3,6,7,8-HxCDD versus 1,2,3,4,7,8-HxCDD ratios, in addition to the relative contributions of specific congeners to the contamination profile (PCBs #118 and #156, PBDEs #28, #47, #99 and #153). In conclusion, unique chemical signatures were observed for each country on the basis of some POP congeners. Future biomonitoring studies will need to consider the high variability of individual exposure profiles in relation to multiple exposure sources but also physiological and metabolic differences.


Assuntos
Poluentes Ambientais/química , Retardadores de Chama/análise , Leite Humano/química , Praguicidas/química , Bifenilos Policlorados/química , Adulto , Animais , Dinamarca , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Feminino , Finlândia , França , Éteres Difenil Halogenados/análise , Humanos , Hidrocarbonetos Clorados/análise , Praguicidas/metabolismo
12.
Lancet ; 363(9417): 1264-9, 2004 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-15094270

RESUMO

BACKGROUND: Several investigators have shown striking differences in semen quality and testicular cancer rate between Denmark and Finland. Since maldescent of the testis is a shared risk factor for these conditions we undertook a joint prospective study for the prevalence of congenital cryptorchidism. METHODS: 1068 Danish (1997-2001) and 1494 Finnish boys (1997-99) were consecutively recruited prenatally. We also established prevalence data for all newborns at Turku University Central Hospital, Finland (1997-99, n=5798). Testicular position was assessed by a standardised technique. All subtypes of congenital cryptorchidism were included, but retractile testes were considered normal. FINDINGS: Prevalence of cryptorchidism at birth was 9.0% (95% CI 7.3-10.8) in Denmark and 2.4% (1.7-3.3) in Finland. At 3 months of age, prevalence rates were 1.9% (1.2-3.0) and 1.0% (0.5-1.7), respectively. Significant geographic differences were still present after adjustment for confounding factors (birthweight, gestational age, being small for gestational age, maternal age, parity, mode of delivery); odds ratio (Denmark vs Finland) was 4.4 (2.9-6.7, p<0.0001) at birth and 2.2 (1.0-4.5, p=0.039) at three months. The rate in Denmark was significantly higher than that reported 40 years ago. INTERPRETATION: Our findings of increasing and much higher prevalence of congenital cryptorchidism in Denmark than in Finland contribute evidence to the pattern of high frequency of reproductive problems such as testicular cancer and impaired semen quality in Danish men. Although genetic factors could account for the geographic difference, the increase in reproductive health problems in Denmark is more likely explained by environmental factors, including endocrine disrupters and lifestyle.


Assuntos
Criptorquidismo/epidemiologia , Peso ao Nascer , Criptorquidismo/classificação , Criptorquidismo/complicações , Dinamarca/epidemiologia , Finlândia/epidemiologia , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Prevalência , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/etiologia
13.
Toxicol Appl Pharmacol ; 207(2 Suppl): 501-5, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16005920

RESUMO

Patients with 45,X0/46XY karyotype often present with intersex phenotype and testicular dysgenesis. These patients may also have undescended testes (cryptorchidism), hypospadias and their spermatogenesis is severely disrupted. They have a high risk for testicular cancer. These patients have the most severe form of testicular dysgenesis syndrome (TDS). We have hypothesized that testicular cancer, cryptorchidism, hypospadias and poor spermatogenesis are all signs of a developmental disturbance that was named as testicular dysgenesis syndrome. The hypothesis is based on clinical and epidemiological findings and on biological and experimental evidence. Signs of TDS share several risk factors, such as small birth weight (particularly being small for gestational age), and they are risk factors for each other. All of them have background in fetal development. They show strong epidemiological links so that countries with high incidence of testicular cancer, such as Denmark, tend to also have high prevalence rates of cryptorchidism and hypospadias and poor semen quality. Vice versa, in countries with good male reproductive health, e.g., in Finland, all these aspects are better than in Denmark. Although genetic abnormalities can cause these disorders, in the majority of cases, the reasons remain unclear. Adverse trends in the incidence of male reproductive disorders suggest that environmental and life style factors contribute to the problem. Endocrine disrupters are considered as prime candidates for environmental influence. Fetal exposure to high doses of dibutyl phthalate was shown to cause a TDS-like phenotype in the rats. Studies are underway to assess whether there is any exposure-outcome relation with selected chemicals (persistent organic pollutants, pesticides, phthalates) and cryptorchidism.


Assuntos
Disgenesia Gonadal/fisiopatologia , Doenças Testiculares/fisiopatologia , Neoplasias Testiculares/fisiopatologia , Animais , Disruptores Endócrinos/toxicidade , Disgenesia Gonadal/induzido quimicamente , Disgenesia Gonadal/genética , Humanos , Cariotipagem , Masculino , Sêmen , Espermatogênese , Doenças Testiculares/induzido quimicamente , Doenças Testiculares/genética , Neoplasias Testiculares/genética
14.
Phys Med Biol ; 50(11): 2689-700, 2005 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-15901963

RESUMO

The dosimetry of exposure to radiofrequency (RF) electromagnetic (EM) fields of mobile phones is generally based on the specific absorption rate (SAR, W kg(-1)), which is the electromagnetic energy absorbed in the tissues per unit mass and time. In this study, numerical methods and modelling were used to estimate the effect of a passive, metallic (conducting) superficial implant on a mobile phone EM field and especially its absorption in tissues in the near field. Two basic implant models were studied: metallic pins and rings in the surface layers of the human body near the mobile phone. The aim was to find out 'the worst case scenario' with respect to energy absorption by varying different parameters such as implant location, orientation, size and adjacent tissues. Modelling and electromagnetic field calculations were carried out using commercial SEMCAD software based on the FDTD (finite difference time domain) method. The mobile phone was a 900 MHz or 1800 MHz generic phone with a quarter wave monopole antenna. A cylindrical tissue phantom models different curved sections of the human body such as limbs or a head. All the parameters studied (implant size, orientation, location, adjacent tissues and signal frequency) had a major effect on the SAR distribution and in certain cases high local EM fields arose near the implant. The SAR values increased most when the implant was on the skin and had a resonance length or diameter, i.e. about a third of the wavelength in tissues. The local peak SAR values increased even by a factor of 400-700 due to a pin or a ring. These highest values were reached in a limited volume close to the implant surface in almost all the studied cases. In contrast, without the implant the highest SAR values were generally reached on the skin surface. Mass averaged SAR(1 g) and SAR(10 g) values increased due to the implant even by a factor of 3 and 2, respectively. However, at typical power levels of mobile phones the enhancement is unlikely to be problematic.


Assuntos
Telefone Celular , Campos Eletromagnéticos/efeitos adversos , Metais/efeitos adversos , Próteses e Implantes/efeitos adversos , Ondas de Rádio , Tecido Adiposo/efeitos da radiação , Algoritmos , Osso e Ossos/efeitos da radiação , Humanos , Metais/efeitos da radiação , Modelos Teóricos , Músculo Esquelético/efeitos da radiação , Pele/efeitos da radiação
15.
APMIS ; 109(2): 96-100, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11399000

RESUMO

Reports based on national registers of congenital malformations have suggested that the birth rate of hypospadias has increased during the last few decades. Register-based information may, however, have pitfalls because of changes in diagnostics, reporting accuracy and registration system. The aim of this study was to determine the current birth rate of hypospadias in Turku University Central Hospital (TUCH) in Finland. This was a prospective study on live-born boys born in TUCH from 1997 to 1999. In the total birth cohort (n=5,798) as well as in a special subcohort group (n=1,505) 0.3% of boys had hypospadias. Only one scrotal hypospadias was found in a boy who had a chromosomal anomaly. Other hypospadias were glandular or coronal. No increase was found in the birth rate of hypospadias when comparing our result with register-based data of boys born in Finland during the years 1970 to 1986 and surgically treated for hypospadias by the age of 8 years. No difference was found either from malformation register-based data concerning the nationwide birth rate of hypospadias during the years 1993 to 1998. Due to differences in national registration systems between countries, prospective studies with equal assessment criteria are needed in order to make reliable international comparisons.


Assuntos
Hipospadia/epidemiologia , Coeficiente de Natalidade , Finlândia/epidemiologia , Humanos , Recém-Nascido , Masculino , Triagem Neonatal , Vigilância da População , Estudos Prospectivos
16.
J Am Coll Surg ; 178(3): 283-7, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8149022

RESUMO

Thirty women experiencing posthysterectomy prolapse of the vaginal vault were treated with abdominal sacral colpopexy between 1984 and 1991. Lyodura (lyophilized cerebral dura mater allograft transplant) was used as the suspensory material in 81 percent and Gore-Tex (reinforced polytetrafluoroethylene) in 16 percent of the operations. There were no perioperative or postoperative complications. At the follow-up examination (mean, three years), good vaginal vault support was observed in 85 percent of the patients. Significant cystocele were seen in 18 percent, and vault prolapse, enterocele, rectocele and chronic perineal laceration each in 15 percent of the patients. At follow-up study, 22 percent of the patients experienced dyspareunia and 41 percent had decreased sexual interest and coital events. Development of stress urinary incontinence in 18 percent of patients was noted. Concomitant Burch colposuspension will cure and prevent stress incontinence and anterior vaginal relaxation. Abdominal sacral colpopexy appears to be a safe and effective method in the treatment of posthysterectomy prolapse of the vaginal vault. In our experience, it seems that coexistent cystocele and rectocele should be corrected in the connection with sacral colpopexy.


Assuntos
Histerectomia/efeitos adversos , Prolapso Uterino/cirurgia , Vagina/cirurgia , Abdome/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Coito , Feminino , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Fatores de Tempo , Resultado do Tratamento , Incontinência Urinária/etiologia , Prolapso Uterino/etiologia
17.
Eur J Obstet Gynecol Reprod Biol ; 57(1): 54-5, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7821505

RESUMO

A vesicocervical fistula is reported. This extremely rare and late sequela of caesarean section, secondary to a lesion in the bladder and unrecognized intraoperatively, was followed with a distressing, long-lasting urinary incontinence unreactive to conservative treatment. Not until 7 years after the primary operation was this lesion diagnosed and treated successfully by vaginal approach. Etiological factors, clinical features and treatment possibilities are discussed.


Assuntos
Fístula/complicações , Fístula da Bexiga Urinária/complicações , Incontinência Urinária por Estresse/etiologia , Doenças Uterinas/complicações , Adulto , Feminino , Fístula/cirurgia , Humanos , Fístula da Bexiga Urinária/cirurgia , Incontinência Urinária por Estresse/cirurgia , Doenças Uterinas/cirurgia
18.
Ann Otol Rhinol Laryngol ; 89(4 Pt 1): 366-9, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7416687

RESUMO

On 100 pathological ears with tympanic membrane perforation, eustachian tube functions was measured by using sonotubometry and the negative pressure equalization test in an attempt to compare these two methods. The pressure equalization test did not appear to be a reliable tool for preoperative clinical determination of tube function because sonotubometry showed tubal opening in 85% (myringoplasty group) and in 49% (radical surgery group) of patholoical ears, which were not able to equalize negative middle ear pressure at all during swallowing. The negative pressure equalization test is considered to be unphysiological and may produce a locking phenomenon of the tube. Even a small negative pressure can act like a valve, producing an obstruction that muscle activity of the tube is no longer able to overcome particularly when mucosal changes are present in the tubal orifice. Sonotubometry is a physiological test and as such gives a reliable picture of the opening of the tube during swallowing. Data on tympanic aeration postoperatively will be reported later.


Assuntos
Otopatias/fisiopatologia , Tuba Auditiva/fisiopatologia , Membrana Timpânica , Adolescente , Adulto , Idoso , Criança , Otopatias/cirurgia , Orelha Média/cirurgia , Humanos , Pessoa de Meia-Idade , Pressão
19.
Int J Gynaecol Obstet ; 42(2): 109-15, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7901057

RESUMO

OBJECTIVE: To analyze which factors, including gynecological surgery in particular, contribute to the occurrence of pelvic relaxation. METHOD: A retrospective analysis of 711 consecutive patients treated surgically for pelvic relaxation from 1983 to 1989 at the Department of Obstetrics and Gynecology of Turku University Central Hospital was undertaken. RESULT: The patients who underwent surgery for recurrent pelvic relaxation were significantly older (66.8 vs. 62.1 years) and suffered significantly less (20% vs. 41%) from urinary stress incontinence than patients undergoing primary surgery for pelvic relaxation. Anterior vaginal segment relaxation (i.e. cysto- and urethrocele) was common in patients undergoing the initial operation (n = 684), and posterior vaginal segment relaxation (i.e. rectocele and perineal laceration) in recurrent operations (n = 58). Of the patients studied, 87 had pelvic relaxation, which had developed after partial (n = 46), total abdominal (n = 16) or vaginal (n = 25) hysterectomy. CONCLUSION: Care must be taken in the treatment of the posterior vaginal segment during the initial operation for pelvic relaxation in order to avoid late sequelae. Moreover, when the removal of the uterus is planned, the matter of a stable vaginal vault must be taken into account especially when partial hysterectomy should be performed.


Assuntos
Prolapso Uterino/cirurgia , Idoso , Feminino , Humanos , Histerectomia/efeitos adversos , Pessoa de Meia-Idade , Recidiva , Reoperação , Estudos Retrospectivos , Prolapso Uterino/epidemiologia , Prolapso Uterino/etiologia
20.
Int J Pediatr Otorhinolaryngol ; 5(1): 11-7, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6682409

RESUMO

Eustachian tube function was determined in 84 children (131 ears) with secretory otitis media (SOM) by means of sonotubometry. Determinations were made prior to myringotomy and insertion of ventilation tubes in conjunction with follow-up testing during the course of SOM. Despite the SOM, 14% of the ears showed normal sound passage through the tube before surgery, and towards the completion of this study tubal function was considered to be normal in 50% of the ears. Although sonotubometry gave a more reliable picture of tubal function in children with SOM, no difference in tubal function could be found among children of various age groups. Because of the large fluctuations in tubal function during the course of SOM, the ventilation tube should not be removed even in cases of apparently normal tubal function at the time of examination.


Assuntos
Tuba Auditiva/fisiopatologia , Otite Média com Derrame/fisiopatologia , Otite Média/fisiopatologia , Adolescente , Criança , Pré-Escolar , Tuba Auditiva/fisiologia , Humanos , Ventilação da Orelha Média , Otite Média com Derrame/cirurgia , Membrana Timpânica/fisiopatologia
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