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1.
Andrologia ; 47(9): 974-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25359661

RESUMO

Previous reports indicated that hyperinsulinaemic men may exhibit a higher percentage of poorly compacted DNA in their spermatozoa and less success in an IVF programme (Andrologia, 45, 2003, 18; Andrologia, 2014, doi: 10.1111/and.12227). The aim of this study was to investigate the effect of metformin (Glucophage®) and antioxidant treatment (StaminoGro®) on the semen parameters of hyperinsulinaemic men. Nineteen hyperinsulinaemic male patients were treated for 3 months with metformin alone (Group A), and fifteen patients used metformin in combination with the nutritional supplement (Group B). Combined data of the two groups (pre- and post-treatment) differ significantly regarding sperm morphology (P = 0.0003) and CMA3 (P < 0.0001) values. The improvement in sperm morphology after treatment was similar for the two respective groups (P < 0.05). The morphological normal sperm forms increased from the mean percentage of 3.9 to 5.5% and from 4.2 to 5.5% for Group A and B respectively. Where a combination of metformin and the supplement were used (Group B), the combination treatment proved to be superior in obtaining enhanced chromatin packaging quality although not statistically significant (P = 0.5929) when compared with the metformin (Group A) group. The chromatin packaging quality in Group B improved with 10% while the improvement in Group A was approximately 8.3%. Therefore, infertile hyperinsulinaemic men can benefit from metformin treatment and should be advised on the use of nutritional supplements with antioxidant properties.


Assuntos
Aminoácidos/uso terapêutico , Antioxidantes/uso terapêutico , Hiperinsulinismo/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Oligoelementos/uso terapêutico , Vitaminas/uso terapêutico , Adulto , Suplementos Nutricionais , Quimioterapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides , Resultado do Tratamento
2.
Andrologia ; 47(7): 759-64, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25220309

RESUMO

Selecting the best spermatozoa for intracytoplasmic spermatozoa injection (ICSI) has recently been a topic of great interest among embryologists. The study aimed to evaluate the relationship between the spermatozoa-hyaluronan-binding assay (HBA), routine semen analysis results and fertilisation rates as recorded during conventional ICSI therapy. Ninety-one patients undergoing conventional ICSI treatment in the Medfem Fertility Clinic in Johannesburg (South Africa) were included in the study. A total of 797 oocytes were injected of which 457 oocytes fertilised (57.3%, range 0-100%). None of the semen parameters correlated with the fertilisation rates (Table 2). HBA scores, however, revealed a highly significant association (p ≤ 0.0001) with the fertilisation rates. The HBA scores also correlated significantly with the biochemical pregnancy values (Spearman r = 0.24, P = 0.02, 95% CI 0.039-0.43); however, the HBA scores did not correlate with the clinical pregnancy rates (Spearman r = 0.14, P = 0.16, 95% CI -0.06 to 0.34). No correlation was recorded between HBA and the standard semen parameters. The study showed that HBA is significantly associated with fertilisation in conventional ICSI. The HBA scores were also significantly associated with the fertilisation rates and biochemical pregnancies.


Assuntos
Ácido Hialurônico/metabolismo , Taxa de Gravidez , Análise do Sêmen , Injeções de Esperma Intracitoplásmicas , Espermatozoides/fisiologia , Feminino , Humanos , Masculino , Gravidez
3.
Andrologia ; 47(1): 91-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24456031

RESUMO

The IVF outcome of a group of hyperinsulinaemic men (group B) was compared with a group of IVF males with normal insulin levels (group A). The participating females in the study groups were younger than 38 years old, had blocked Fallopian tubes and/or endometriosis, had normal insulin levels and produced five or more ova on stimulation. The male participants in both groups were normozoospermic with motility above 50% and sperm morphology between 5 and 13% normal forms (G-pattern according to Tygerberg strict criteria). The two groups did not differ statistically in terms of age or semen parameters (P = 0.39; P < 0.05).The group of men that presented with normal insulin levels had a higher fertilisation rate (79.15% versus 74.57%) and superior embryo quality on day 3 (55.77% versus 50.39%) than the group that presented with hyperinsulinaemia, but these differences were not statistically significant (P = 0.28, P = 0.40; P < 0.05). The clinical pregnancy rate of the group with normal insulin was significantly higher than that of the hyperinsulinaemic group, 57.9% versus 31.8% respectively (P = 0.03). The results suggest that hyperinsulinaemia had a negative impact on IVF outcome and patients should be advised accordingly.


Assuntos
Fertilização in vitro , Fertilização , Hiperinsulinismo , Infertilidade Feminina/terapia , Insulina/sangue , Taxa de Gravidez , Adulto , Blastocisto , Estudos de Casos e Controles , Empacotamento do DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Análise do Sêmen , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Resultado do Tratamento
4.
Andrologia ; 45(1): 18-25, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22571794

RESUMO

The aim of this study was to investigate the prevalence of hyperinsulinaemia in a group of normozoospermic donors and the influence of insulin levels on in vitro fertilisation (IVF) outcome. Fasting insulin and 2 h post-eating insulin levels were determined for a group of thirty-four sperm donors. They were divided into three groups according to their insulin profiles. The association between insulin levels and embryo quality was determined in a clinical study for the different groups. The prevalence of raised insulin in the donor group was 44% with a 95% confidence interval of 27.2% and 62.1%. Donors with normal insulin levels produced more good quality blastocysts in the IVF programme than those with abnormal insulin levels. These differences were not statistically significant (P=0.8638). Embryo quality in an IVF programme may be influenced by male insulin levels. The role of insulin in male fertility needs to be investigated.


Assuntos
Hiperinsulinismo/epidemiologia , Doadores de Tecidos , Adulto , Blastocisto/fisiologia , Índice de Massa Corporal , Jejum , Fertilidade/fisiologia , Fertilização in vitro , Humanos , Insulina/sangue , Insulina/fisiologia , Estilo de Vida , Masculino , Período Pós-Prandial , Análise do Sêmen , América do Sul/epidemiologia , Inquéritos e Questionários , Resultado do Tratamento
5.
Tijdschr Diergeneeskd ; 131(12): 438-42, 2006 Jun 15.
Artigo em Holandês | MEDLINE | ID: mdl-16830510

RESUMO

On dairy farms covered by the ambulatory service of the Department of Farm Animal Health, 55 Holstein-Friesian cows with suspected ovarian follicular cysts on the basis of rectal palpation underwent confirmatory transrectal ultrasonography. An ovarian follicular cyst was confirmed in 28 cows (50.9%) and was treated by single transvaginal-guided needle aspiration. Cows with a corpus luteum or a luteinized cyst were not treated. After aspiration, 82.1% (n=23) of the cows showed oestrus behaviour at 13.3 +/- 6.0 days. Artificial insemination was performed during the first heat after cyst aspiration and resulted in a pregnancy rate of 64.2%. In conclusion, single transvaginal-guided needle aspiration of ovarian follicular cysts is an easy and good method for the treatment of follicular cysts. Moreover, it is a safe and good alternative method for the manual, active rupturing of cysts during rectal palpation.


Assuntos
Biópsia por Agulha Fina/veterinária , Doenças dos Bovinos/terapia , Cisto Folicular/veterinária , Cistos Ovarianos/veterinária , Animais , Biópsia por Agulha Fina/instrumentação , Biópsia por Agulha Fina/métodos , Bovinos , Doenças dos Bovinos/diagnóstico por imagem , Estro/fisiologia , Feminino , Fertilidade , Cisto Folicular/diagnóstico por imagem , Cisto Folicular/terapia , Cistos Ovarianos/diagnóstico por imagem , Cistos Ovarianos/terapia , Folículo Ovariano , Gravidez , Taxa de Gravidez , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia , Vagina/diagnóstico por imagem
6.
Mol Cell Endocrinol ; 180(1-2): 13-24, 2001 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-11451567

RESUMO

The identification and characterization of components of the transforming growth factor beta (TGFbeta) signalling pathway are proceeding at a very fast pace. To illustrate a number of our activities in this field, we first summarize our work aiming at the selection from a large collection of single residue substitution mutants of two activin A polypeptides in which D27 and K102, respectively, have been modified. This work has highlighted the importance of K102 and its positive charge for binding to activin type II receptors. Activin K102E, which did not bind to high-affinity receptor complexes, may be a valuable beta chain, when incorporated in recombinant inhibin to unambiguously detect novel inhibin binding sites at the cell surface. We then illustrate how Smad5 knockout mice and an overexpression approach with a truncated TGFbeta type II receptor in the mouse embryo can contribute to the identification of a novel TGFbeta-->TbetaRII/ALK1-->Smad5 pathway in endothelial cells in the embryo proper and the yolk sac vasculature. We conclude with a summary of our results with a Smad-interacting transcriptional repressor but focus on its biological significance in the vertebrate embryo.


Assuntos
Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Receptores de Ativinas/metabolismo , Ativinas/genética , Ativinas/metabolismo , Animais , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/fisiologia , Interações Medicamentosas , Proteínas de Homeodomínio/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Fosfoproteínas/metabolismo , Fosfoproteínas/fisiologia , Proteínas Repressoras/farmacologia , Proteína Smad5 , Transativadores/metabolismo , Transativadores/fisiologia , Vertebrados/embriologia , Homeobox 2 de Ligação a E-box com Dedos de Zinco
7.
Psychol Aging ; 16(1): 110-27, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11302360

RESUMO

Novice (Experiment 1) and experienced (Experiment 2) young, middle-aged, and older adults learned a new word-processing application in keystrokes, menus, or menus-plus-icons interface conditions. Novices showed strong age differences in the time to complete the 3-day tutorial and in declarative and procedural tests of word-processing knowledge. Menus and menus-plus-icons were superior to keystrokes condition. though interface did not interact with age. Experienced users showed age-related slowing in learning rate but minimal age differences in test performance when retrained on a new word-processing program. Age and computer experience accounted for much of the variance in both learning time and word-processing performance; interface type, speed of processing, and spatial generation ability made additional contributions. Experience interacted with age to predict performance. Implications for training and retraining older workers are discussed.


Assuntos
Cognição/fisiologia , Memória/fisiologia , Desempenho Psicomotor , Ensino , Vocabulário , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Atenção/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Tempo de Reação
8.
Dev Dyn ; 218(4): 663-70, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10906784

RESUMO

SMAD proteins are downstream targets of serine/threonine kinase receptors of the transforming growth factor beta (TGF beta) superfamily. Ligands activating these receptors regulate cell growth, differentiation and development in many tissues of various organisms. In mammals eight different Smad genes are known, each with different roles in mediating signalling between plasma membrane and nucleus. Smad6 and Smad7 are inhibitors of TGF beta family signalling. They are both expressed in human adult vascular endothelial cells, particularly after these cells have been subjected to shear stress (Topper et al. [1997] Proc Natl Acad Sci USA 94:9314-9319). Here we show by reverse transcriptase polymerase chain reaction and in situ hybridization that Smad7 mRNA is highly expressed in the developing vascular system of the mouse embryo but is also detectable much earlier in preimplantation embryos and during gastrulation. We also demonstrate by transient transgenesis that overexpression of Smad7 in mouse zygotes inhibits development beyond the 2-cell stage. This confirms earlier conclusions of similar, but complementary, experiments using a dominant negative type II TGF beta receptor demonstrating that TGF beta signalling is required for normal preimplantation development.


Assuntos
Vasos Sanguíneos/embriologia , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/metabolismo , Transativadores/biossíntese , Transativadores/metabolismo , Regulação para Cima , Animais , Blastocisto/metabolismo , Northern Blotting , DNA Complementar/metabolismo , Proteínas de Ligação a DNA/genética , Endoderma/metabolismo , Gástrula/metabolismo , Hibridização In Situ , Mesoderma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Smad7 , Fatores de Tempo , Distribuição Tecidual , Transativadores/genética , Fator de Crescimento Transformador beta/biossíntese
9.
Can J Exp Psychol ; 51(2): 99-111, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9340078

RESUMO

In typing, when the fingers executing two successive movements are on the same hand, the time between keystrokes is longer than when the fingers are on different hands. Biomechanical limitations of the hands are thought to account for this difference. The generality of this finding was explored by investigating skilled pianists' performance of two successive notes. Experiment 1 failed to find comparable differences in timing as a function of the hands involved. Experiment 2, employing both a piano production and a typing task, replicated the previous piano performance results, and revealed that the timing differences in typing were limited to letter sequences requiring fore-aft and lateral finger movements. Experiment 3 extended this finding to piano performance. Together, these findings clarify the nature of biomechanical constraints on skilled manual performance.


Assuntos
Destreza Motora , Música , Fenômenos Biomecânicos , Dedos/fisiologia , Lateralidade Funcional/fisiologia , Humanos , Destreza Motora/fisiologia
10.
Arch Androl ; 33(1): 7-10, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7979812

RESUMO

Frozen semen samples are generally used today for artificial insemination and in vitro fertilization (IVF) and have various advantages above freshly produced semen. A disadvantage is that substances may leak out of the sperm if the membrane is damaged during freezing. In this study sperm ATP concentration was determined before freezing and after thawing and correlated with fertilization in an IVF program. After freezing and thawing the average sperm motility decreased significantly (p < or = .0001). Sperm ATP concentration was also significantly lower after freezing and thawing (p = .0004). Sperm ATP concentration after thawing did not correlated with fertilization. ATP concentration was a good marker of cryolysis but not of fertilization.


Assuntos
Trifosfato de Adenosina/análise , Criopreservação , Preservação do Sêmen , Motilidade dos Espermatozoides , Espermatozoides/química , Espermatozoides/citologia , Feminino , Fertilização in vitro , Congelamento , Humanos , Inseminação Artificial , Masculino , Oócitos/fisiologia , Espermatozoides/fisiologia
11.
J Assist Reprod Genet ; 11(1): 38-42, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7949834

RESUMO

PURPOSE: The bioassay used by most IVF units to assess culture media is the mouse embryo test. The limitations of this assay are well known. The objective of this study was therefore to evaluate the in vitro bioassay potential of rodent sperm, in terms of relative sensitivities to endotoxins, and to compare the results with the routine mouse embryo and human sperm tests. RESULTS: The greater sensitivity of rodent sperm than of mouse embryos was evident in this study. A further advantage in using the mouse sperm test was the time (4-6 hr) in which endotoxins could be detected. CONCLUSION: This rapid sperm test proved to be inexpensive, convenient, and invaluable for detecting potential sources of cytotoxicity.


Assuntos
Meios de Cultura/química , Embrião de Mamíferos/efeitos dos fármacos , Endotoxinas/análise , Endotoxinas/farmacologia , Sensibilidade e Especificidade , Espermatozoides/efeitos dos fármacos , Animais , Embrião de Mamíferos/fisiologia , Feminino , Humanos , Masculino , Métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Gravidez , Espermatozoides/fisiologia
12.
Exp Aging Res ; 20(1): 45-59, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8194575

RESUMO

Increased age is associated with declines in perceptual and psychomotor performance. We review several surveys of health and disability that provide functional descriptions on population trends in vision, hearing, fitness, mobility, and agility that complement laboratory studies of perceptual threshold functions. Women report and exhibit significantly greater disability than men (the exceptions being disabilities associated with hearing and flexibility), with the disability progression accelerating with age. For the growing proportion of older adults in the labor force, visual improvements can be achieved through improved lighting, increased size of visual detail, and glare avoidance. For hearing, restricting the frequency of sounds to the 1000- to 2000-Hz range, minimizing background noise, and eliminating reverberation seem prudent. For the retired population, emphasis should be placed on minimizing disability by promoting greater use of assistive devices and environmental redesign. Future laboratory studies of perceptual and psychomotor functions should attempt to sample more representatively and target underrepresented groups of older adults. New field studies are needed to bridge the gap between survey self-reports and laboratory studies and to determine the cost and benefits of redesign.


Assuntos
Envelhecimento/fisiologia , Percepção , Desempenho Psicomotor , Idoso , Planejamento Ambiental , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos da Percepção/epidemiologia , Prevalência , Transtornos de Sensação/epidemiologia
13.
Psychol Aging ; 8(1): 87-102, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8461120

RESUMO

Eighty typists ranging in age from 21-71 years and in skill from 24-110 net words per minute participated in 2 experiments examining age-related differences in the motoric aspects of transcription typing skill. Age- and skill-related differences were examined for 2 simplified typing tasks: letter reaction time, which assessed latency to type a single keystroke, and digraph typing, which assessed the latencies to type 2 consecutive keystrokes. A finger tapping and choice reaction time task were also included. The results indicated that low-skill, older typists exhibited a deficit in both the translation and the execution components of motor performance, whereas high-skill, older typists exhibited a deficit in translation only. An additional task that manipulated preview of the text to be typed replicated the findings of Salthouse (1984), suggesting that older typists compensate for age-related slowing by beginning keystroke preparation sooner.


Assuntos
Envelhecimento/psicologia , Destreza Motora , Desempenho Psicomotor , Adulto , Idoso , Atenção , Feminino , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Prática Psicológica , Tempo de Reação
14.
S Afr Med J ; 83(1): 43-6, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8424204

RESUMO

This retrospective study was conducted to ascertain the success rate of a university-based in vitro fertilisation (IVF) programme. Over a 4-year period a total of 881 patients was aspirated with an 81.8% embryo transfer (ET) rate. This resulted in 150 biochemical pregnancies (20.8% per ET), and 92 births that produced 100 babies were recorded (12.8% per ET). Multiple pregnancies accounted for 8.7% of births and 6.5% of the 100 babies presented with minor congenital abnormalities. Delivery took place by caesarean section in 46% of cases. Birth mass of babies ranged from 1.06 to 4 kg with a mean of 2.944 +/- 0.629 kg. Mean gestational age was 260 +/- 18.2 days. Twenty-three percent of babies born were preterm, 13.8% of these were twins and presented with a low birth mass. It was concluded that the conception rate of patients did not differ with regard to the number of IVF attempts but that those who conceived during the first two attempts had a significantly better chance (P < 0.05) of carrying to term.


Assuntos
Fertilização in vitro , Resultado da Gravidez , Aborto Espontâneo/etiologia , Adulto , Transferência Embrionária , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez
15.
S Afr Med J ; 78(4): 203-4, 1990 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-2382177

RESUMO

The outcome of in vitro fertilisation and embryo transfer in 90 couples where the husband's normal sperm morphology was less than 15% were analysed. Based on the percentage of morphologically normal spermatozoa the patients were divided into three groups: group A--normal morphological features 0-5%; group B--6-10%; and group C--11-14%. A control group had normal morphological features greater than or equal to 15%. The fertilisation rate and number of embryos transferred was not significantly different in these groups. However, the pregnancy rate per embryo transfer was significantly different for groups A and B compared with group C and the control group (0% and 5.9% for groups A and B v. 13.9% and 18.3% for group C and the control group, respectively). It is concluded that when the normal sperm morphology is less than 11% the prospect of a pregnancy is poor.


Assuntos
Transferência Embrionária , Fertilização in vitro , Espermatozoides/patologia , Humanos , Masculino
16.
S Afr Med J ; 77(7): 368-9, 1990 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-2321109

RESUMO

In retrograde ejaculation sperm is passed into the bladder causing infertility. Among patients seen at the Reproductive Biology Research Unit of the University of Pretoria retrograde ejaculation is relatively uncommon (0.004%), but is a potentially treatable cause of infertility. The technique for collecting sperm, sperm processing and recovery described was successful and resulted in a pregnancy after transfer of 1 four-cell embryo.


Assuntos
Fertilização in vitro , Infertilidade Masculina , Ejaculação , Fertilização in vitro/métodos , Humanos , Masculino
17.
Tijdschr Soc Wet ; 34(3): 215-35, 1989.
Artigo em Holandês | MEDLINE | ID: mdl-12343062

RESUMO

PIP: The consequences and policy implications of recent demographic changes in the OECD member countries are examined at the individual, family, and national levels, with the focus on changes in fertility. The need for development of social and economic policies in response to demographic changes is noted, as well as the need to develop policies that might influence demographic trends. The authors conclude that the main policy dilemma concerns how to ensure that the quality of life of parents choosing to have more children is not adversely affected.^ieng


Assuntos
Coeficiente de Natalidade , Demografia , Países Desenvolvidos , Dinâmica Populacional , Política Pública , Qualidade de Vida , Economia , Fertilidade , População , Seguridade Social
18.
Tijdschr Soc Wet ; 30(4): 316-29, 1985.
Artigo em Holandês | MEDLINE | ID: mdl-12268385

RESUMO

PIP: Policy measures affecting fertility, recently adopted in Belgium, are reviewed. The author notes that although responsibility for population matters has been delegated to the respective language groups, the responsibility for family law, divorce, abortion, social security, taxation, and labor policy remains a national responsibility. There are currently no measures in these areas adopted primarily for demographic reasons. Differences between the approaches taken by the French- and Dutch-speaking communities are noted. The author suggests that the French-speaking community has focused on problems relating to contraception and abortion, and the Dutch-speaking community has emphasized social welfare and family policy^ieng


Assuntos
Aborto Induzido , Anticoncepção , Divórcio , Política de Planejamento Familiar , Fertilidade , Legislação como Assunto , Política Pública , Previdência Social , Seguridade Social , Impostos , Bélgica , Demografia , Países Desenvolvidos , Economia , Europa (Continente) , Serviços de Planejamento Familiar , Administração Financeira , Financiamento Governamental , Idioma , Casamento , População , Dinâmica Populacional
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