Aluminium, cadmium and lead concentrations in the spermatozoa and seminal plasma of 27 employees of two industrial companies, a refinery and a polyolefin factory, and 45 consecutive sperm donor candidates at a sperm bank were studied using atomic absorption measurements. The relationship between metal concentration and parameters of semen analysis was studied. A high concentration of aluminium in spermatozoa was correlated with decreased sperm motility. The concentrations of cadmium and lead were low and did not show any correlation with parameters of semen analysis. Aluminium may be one of the environmental pollutants causing impaired semen quality. The mean sperm concentrations were similar in the factory employees (96 x 10(6)/ml), in the sperm donor candidates of the comparison group (104 x 10(6)/ml) and in 352 donor candidates at the sperm bank of the Family Federation of Finland (107 x 10(6)/ml) between May 1993 and May 1995.
The authors discuss the problem of selective derivation of the genetic material of spermatozoa for molecular genetic identification from mixed biological traces containing sperm on material evidence. Possible methods of improving the efficacy of differential lysis of cells present in mixed traces are analyzed. Effects of some routinely used extractants on biological substrata, most often contaminating the sperm in expert material, have been studied, and conditions for their most complete elimination from objects of investigation optimized.
To analyse the factors predisposing to male immunological infertility from the hospital records of 508 patients that had been treated for infertility in the Turku University Central Hospital from 1980 to 2000. In addition, the hormonal status was investigated at the beginning of treatment.
Patients with a history of mumps, or either a fresh varicocele or a history of varicocele had statistically significant lower levels of MAR antisperm antibodies (ASAs) than patients with no such conditions. Repair of varicocele (either surgical or embolisation), showed a statistically significant enhancement of the total sperm cell counts in ejaculates, but it appeared not to have any influence on other parameters of the semen analysis (mobility and morphology). Of all male infertility patients, 66.3% had normal hormonal status at the beginning of treatment, 12.6% of patients had hypotestosteronemia and 22.1% had subclinical hypogonadism. Patients with subclinical hypogonadism had lower total sperm cell count in ejaculates than patients with normal hormonal status although they had statistically significant more offspring. In addition, it appeared that mumps orchitis as well as smoking and alcohol abuse are risk factors for subclinical hypogonadism.
No clear predisposing factor for male immunological infertility could be found. However, patients with subclinical hypogonadism differed from other male infertility patients and thus may form a special group among the male infertility patients.
Hereditary nonpolyposis colon cancer (HNPCC) has been shown to be caused by mutations in the mismatch repair genes hMSH2, hMLH1, hPMS1, and hPMS2. Recent evidence has demonstrated that mutations in mismatch repair genes disrupt meiosis in mice. A large HNPCC kindred in Newfoundland, Canada, has an hMSH2 mutation-an A-->T transversion at the +3 position of the splice-donor site of exon 5. We have studied sperm from men with this hMSH2 mutation, since it is possible that mismatch repair mutations in humans might also have an effect on meiosis and normal segregation of chromosomes. The frequencies of aneuploid and diploid sperm were determined in 10 men with the hMSH2 mutation, by use of multicolor FISH analysis for chromosomes 13, 21, X, and Y. A minimum of 10,000 sperm per man was studied per chromosome probe. Control individuals consisted of men in the same kindred with HNPCC who did not carry the mutation and of other normal men from Newfoundland. A total of 321,663 sperm were analyzed: 200,905 sperm were from men carrying the hMSH2 mutation and 120,758 sperm were from control men. There was a significantly increased frequency of disomy 13, disomy 21, XX, and diploidy in mutation carriers compared with control men. These results suggest that the hMSH2 mutation may affect meiosis in humans.
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BACKGROUND: Endosulfan has been used for over 50 years. Although most analogs have been discontinued, endosulfan has less environmental persistence. Nevertheless, pressure groups are lobbying for a worldwide ban. The reasons are: possible rodent male reproductive toxicity, other endocrine effects and cancer; human epidemiology, and exposure studies; residues appearing in remote areas of the world, e.g., the Arctic. METHODS: The endosulfan toxicology database is described and risks of its use assessed. RESULTS: Endosulfan is an antagonist at the GABA(A) receptor Cl(-) ionophore in mammalian CNS. Rat acute toxicity is moderate, LD(50)=48 (M) or 10 mg/kg/d (F), oral gavage; 130 (M), 70 mg/kg/d (F) dermal; LC(50)=34.5 microg/L (M), 12.6 microg/L (F), inhalation. Critical NOELs for risk assessment: acute oral (gavage)=0.7 mg/kg/d (rabbit developmental); Subchronic oral (diet)=1.2 mg/kg/d (rat reproduction); Chronic oral (diet)=0.6 mg/kg/d. There were no acceptable dermal toxicity studies. The critical acute and subchronic inhalation NOELs=0.001 mg/L, chronic inhalation=0.0001 mg/L (estimated). Toxicity to rat sperm occurred at doses causing neurotoxicity. Endocrine effects, resulting from P450 oxygenase(s) induction, were reversible. Increased cancer, genotoxicity, or histopathology in rodents was not observed in any organ. Possible effects on brain biogenic amine levels were probably secondary. CONCLUSIONS: Epidemiology and rodent studies suggesting autism and male reproductive toxicity are open to other interpretations. Developmental/ reproductive toxicity or endocrine disruption occurs only at doses causing neurotoxicity. Toxicity to the fetus or young animals is not more severe than that shown by adults.
The practice of informed consent in biomedicine is so widely spread that it must be considered the most important principle within bioethics, and the most universally appealed to within recent legislation. There seems to be a consensus as to its value in research on autonomous persons, but also a problem concerning its application when dealing with people having a serious mental, social or even physical disability. Within the field of artificial procreation there are even more problems. Informed written consent is often demanded from anonymous donors of gametes in order to ensure their consent to the legal and moral consequences of their anonymity. The child resulting from the artificial procreation, on the contrary, cannot consent to, nor be informed before being conceived, of the secrecy laid on the identity of its genetic parents. Some countries resolve this problem by allowing the children, when they reach their majority, to obtain some information pertaining to the health or the identity of their genetic parents. This presents ethical problems. It can be argued that the anonymity of the parents chiefly affects the children, so that an agreement on this point among parents, doctors and others must be regarded as invalid. The paper will argue that a law ensuring the complete anonymity of the parents is disregarding the informed consent and the interests of the children resulting from artificial procreation, and is thus doing more damage to society than good.
Since Sweden abolished anonymity in connection with sperm donation in 1985, a number of other countries have followed suit. A legal provision still exists in Denmark to the effect that the donor must be anonymous. Arguments given in a Danish context against retaining the present scheme involving anonymous sperm donation will be discussed. The biggest problem with sperm donation seems to be non-disclosure. Current and important arguments in favour ofabolishing anonymity are that it sends out a clear signal that non-disclosure is unacceptable and that, in principle, all citizens should have access to the information available about themselves. However, the arguments can be criticised both from theoretical (legal) and several practical (medical) points of view. A substantive alternative to abolishing anonymity might be to inform parents about avoiding non-disclosure--and to design information material for the children, to support the parents.
The impact of demographic, lifestyle, and seminal factors on the sperm chromatin structure assay (SCSA) parameters was evaluated in a population of 277 healthy Danish men. This cohort was established within the framework of a European Concerted Action on occupational hazards to male reproductive capability in order to examine the possible reproductive effects of exposure to styrene or pesticides. The SCSA measures the susceptibility of sperm DNA to in-situ acid-induced denaturation, by multiparameter flow cytometric analysis after staining with the DNA-specific fluorescent dye acridine orange. The green versus red bivariate cytogram patterns were quite variable among donors, showing a wide heterogeneity of sperm DNA denaturability. Nevertheless, in those cases where we had the possibility to measure two semen samples from the same donor, the cytogram pattern remained stable over time (0.64
The semen characteristics of 100 fertile indigenous blacks were studied. The mean semen volume was 2.6 ml, sperm density 55 million/ml, motility 61% and well-formed sperm 71%. These figures are comparable to those of similar recent studies in Caucasians but differ significantly from earlier studies. Our data seem to support recent observations that there has been a decline in the sperm density of fertile males in the past 3 decades and that the earlier standards of sperm concentration may be too high for the present.