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Biomedical subjects

B L Bordson

Publications and source records attributed to B L Bordson.

9 recordsLinked to original sources
PubMed1992

Air-conditioned environments do not prevent deterioration of human semen quality during the summer.

OBJECTIVE: To determine if air conditioning might mitigate summer reductions in semen quality. DESIGN: Prospective study of semen quality in summer and winter. SETTING: Normal human volunteers were studied in the setting of a fertility laboratory. PATIENTS, PARTICIPANTS: Two groups of volunteers were selected from the vicinity of New Orleans: 64 men who worked indoors during the summer in air-conditioned environments and 76 others who worked outdoors. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Parameters of manual semen analysis were examined for seasonal and group differences. RESULTS: Remarkably similar reductions in semen quality during summer as compared with winter were observed in both indoor and outdoor workers, respectively, with regard to the following parameters of semen quality: 19% and 19% in sperm concentration, 25% and 27% in total sperm per ejaculate, 17% and 20% in motile sperm concentration, 13% and 15% in percent sperm with normal morphology, and 23% and 23% in concentration of morphologically normal motile sperm. CONCLUSIONS: These findings do not support the hypothesis that the heat of the summer is detrimental to male reproductive capacity. The available evidence suggests instead a possible role of photoperiod in causing the seasonal changes in semen quality.

Adolescent↗
PubMed1991

The appropriate upper age limit for semen donors: a review of the genetic effects of paternal age.

There is little evidence to support a correlation between increased paternal age and the incidence of chromosome anomalies. Though a few early studies demonstrated an increased risk of Down syndrome with advanced paternal age, especially after the age of 55, numerous later studies failed to confirm any paternal age effect. Among structural chromosome anomalies, only the inherited reciprocal translocations were found to be more common among children of older fathers. Chromosome analysis of semen donors would rule out this problem. There is evidence, however, that the incidence of serious nonchromosomal birth defects, especially those arising from new autosomal mutations, increases with paternal age. Risk estimates have been established for increased paternal age and contribution to new dominant mutations. The established association between increased paternal age and new autosomal mutations and the fact that most of the disorders associated with such mutations cannot be prenatally diagnosed may be important in establishing the upper age limit for semen donors. Recommendations from the literature are interpreted to advise men to have their children before age 40. This suggestion would obviously benefit immediate offspring and perhaps successive generations as well. The limit of 35 years set by AATB standards, therefore, is in harmony with such benefit, but may be too stringent in eliminating potential donors. Accordingly, the Reproductive Council of the AATB has initiated steps to modify its standards to the age limit of 40.

Chromosome Aberrations↗
PubMed1988

Deterioration of semen quality during summer in New Orleans.

A retrospective investigation of semen quality was undertaken at a fertility clinic in New Orleans. Semen specimens obtained during the summer had significantly lower sperm concentration, total sperm per ejaculate, percent motile sperm, and motile sperm concentration than samples provided at other times of year. Substantial summer deterioration in semen quality was likely to occur only among men whose work places were probably not air-conditioned. These findings suggest that the deleterious effects of summer heat on spermatogenic cells or on epididymal spermatozoa may reduce male fertility and account, at least partially, for the deficit of spring births in warm climates throughout the world.

Analysis of Variance↗
PubMed1986

Comparison of fecundability with fresh and frozen semen in therapeutic donor insemination.

A series of 401 therapeutic donor insemination (TDI) cycles was analyzed for determining the effect on fecundability of fresh versus cryopreserved semen, the number of inseminations per cycle, recipient age, and the reproductive health of the TDI recipient. We followed a protocol in which inseminations were performed during the periovulatory period determined by urinary luteinizing hormone surge or ultrasound-timed human chorionic gonadotropin injection. The minimum standard for insemination with fresh or cryopreserved semen was a total of 40 X 10(6) grade 3 sperm. We found no decreased fecundability when using frozen semen, rather than freshly ejaculated specimens. The number of inseminations per cycle did not affect the pregnancy outcome after TDI. The reproductive health of the recipient had a significant effect on the pregnancy rate. Fecundability was 15.6% for healthy women, as compared with 6.7% for women with a diagnosis of moderate, severe, or extensive endometriosis, pelvic adhesions, tubal disease, or ovulatory dysfunction. To avoid transmission of human T-lymphotropic virus type III from sperm donor to TDI recipient, we have recently utilized an exclusively frozen TDI program. With well-timed inseminations of 40 X 10(6) grade 3 motile sperm, we have been able to attain pregnancy rates similar to those previously obtained with fresh samples.

Female↗
PubMed1984

NOR associations with heterochromatin.

Associations between nucleolus organizer regions (NORs) and non-acrocentric chromosomes were scored in 2,800 metaphase spreads from PHA-stimulated lymphocyte cultures (48 h) from 14 individuals. The preparations were both silver stained and C-banded. In order to calculate the expected values for associations, the ratio of heterochromatin length to euchromatin length was established for each subject. Individual C-band lengths and centromeric lengths were also determined. When silver connective (SC) associations with heterochromatin were compared to SC associations with euchromatin, the number of associations with heterochromatin was significantly greater than expected (P less than 0.000001) for each subject. The SC associations were not distributed randomly over the heterochromatin of the non-acrocentrics. Chromosomes 1 and 2 had significantly more than expected. Chromosomes 17, 18, 19, 20, and the Y had fewer than expected. NOR associations with euchromatic segments also showed a nonrandom pattern of distribution.

Chromosome Banding↗
PubMed1984

A method for combined C-banding and silver staining.

A reliable technique for combined C-banding and silver staining of metaphase chromosomes which uses trypsinization is described. Slides are first immersed in dilute HCl to remove residual cytoplasm from around the chromosomes. They are then treated with saturated barium hydroxide and incubated overnight in saline sodium citrate (0.30 M NaCl, 0.03 M sodium citrate, adjusted to pH 7.0 with HCl). Following the C-banding pretreatment, a two-step method of silver staining which employs a protective colloidal developer is used to stain the nucleolar organizer regions (NORs) of the chromosomes. Silver staining is followed by trypsinization to remove extraneous silver precipitate from the chromosome arms which permits the C-bands to be stained with Giemsa. The method works equally well with fresh and aged mitotic chromosome preparations and gives consistent staining of both heterochromatin and active NORs in metaphases across the slide.

Chromosome Banding↗
PubMed1983

NOR activity and satellite association patterns in a family carrying a doubly satellited marker.

Activity and association patterns of nucleolar organizer regions (NORs) were studied in cultured blood lymphocytes from six members of a family, three of whom carried a doubly satellited marker. The marker consisted of a centromere with two sets of satellites and stalks which showed consistent NOR activity. The children with the marker had significantly higher frequencies of NOR activity and satellite association than their non-carrier siblings. The acrocentrics of the children with the marker did not appear to have decreased association tendency.

Cells, Cultured↗