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Biomedical subjects

R H Martin

Publications and source records attributed to R H Martin.

At least 55 records · Page 3Linked to original sources
PubMed1995

Chromosomal analysis of sperm from men with idiopathic infertility using sperm karyotyping and fluorescence in situ hybridization.

OBJECTIVE: To determine if idiopathic infertile men having oligozoospermia, asthenozoospermia, or teratozoospermia have an elevated risk of transmitting chromosomal abnormalities to their offspring. DESIGN: Sperm chromosomal complements from five somatically normal infertile men were assayed using the human sperm-hamster oocyte fusion system and the disomy frequencies for chromosomes 1, 12, and the sex chromosomes were determined using fluorescence in situ hybridization. SETTING: Infertile men and normal donors were volunteers in an academic research environment. PATIENTS: Five men with the appropriate semen characteristics were recruited among patients concerned about their infertility. INTERVENTIONS: Sperm fused with hamster oocytes resulting in sperm chromosomes or the sperm nuclei were prepared for fluorescence in situ hybridization. MAIN OUTCOME MEASURE: Structural and numerical abnormalities assessed by sperm karyotypes and the disomy frequency determined by fluorescence in situ hybridization analysis. RESULTS: The infertile men showed increased frequencies of numerical abnormalities and total abnormalities as determined by sperm karyotyping. Analysis of sperm nuclei by fluorescence in situ hybridization indicated a significant increase in the frequency of disomy for chromosome 1 and XY disomy. CONCLUSIONS: Sperm from infertile men may contain an increased frequency of chromosomal abnormalities.

Adult↗
PubMed1995

Sperm chromosome complements in a man heterozygous for a reciprocal translocation 46,XY,t(9;13)(q21.1;q21.2) and a review of the literature.

Sperm chromosome complements were studied in a man heterozygous for a reciprocal translocation t(9;13)(q21.1;q21.2). A total of 89 spermatozoa were karyotyped after in vitro penetration of hamster eggs. The frequencies of alternate, adjacent 1 and adjacent 2 segregations were 46.9%, 35.8% and 17.3% respectively. For alternate segregation, the number of normal spermatozoa (21) was not significantly different from the number of spermatozoa carrying a balanced form of the translocation (17), as theoretically expected. The proportion of spermatozoa with an unbalanced form of the translocation was 53.1%. There was no evidence for an interchromosomal effect since the frequency of numerical abnormalities (unrelated to the translocation) was within the normal range of control donors. Data from a total of 31 reciprocal translocations studied by sperm chromosomal analysis were reviewed.

Adult↗
PubMed1995

Aneuploidy in human sperm: results of two-and three-color fluorescence in situ hybridization using centromeric probes for chromosomes 1, 12, 15, 18, X, and Y.

To understand the mechanisms that affect aneuploidy, fluorescence in situ hybridization (FISH), using chromosome-specific centromeric probes, was employed to screen a large population of human sperm for numerical errors. To determine the true rate of disomy for chromosomes 1, 12, 15, and 18, two-color FISH was performed, and for the gonosomes, three-color FISH. The use of multiple, differently colored probes allows one to distinguish a true disomic sperm from a diploid cell. A minimum of 10,000 sperm nuclei from each of five donors was scored per set of centromeric probes, giving a total of 165,330 sperm nuclei. The disomy frequencies for autosomes 1, 12, 15, and 18 were found to be similar, with a mean of 0.10% (range, 0.05%-0.16%) for chromosome 1, 0.16% (0.10%-0.25%) for chromosome 12, 0.11% (0.07%-0.20%) for chromosome 15, and 0.11% (0.08%-0.17%) for chromosome 18. For the sex chromosomes, the mean frequency of disomy was found to be 0.43% (range, 0.23%-0.71%), with XX disomy accounting for 0.07% (0.03%-0.10%), YY disomy 0.21% (0.10%-0.43%), and XY disomy 0.15% (0.08%-0.24%). The incidence of disomic sperm for the sex chromosomes was significantly increased, compared to the frequency of disomy for the autosomes (chi 2 = 218.61, P < 0.0001). Diploidy was observed in 0.05%-0.47% of the sperm nuclei counted. Interdonor heterogeneity for disomy frequencies was found to exist for the sex chromosomes and for chromosomes 1 and 15, suggesting significant variation among normal men.

Adult↗
PubMed1995

Relationship between risk factors, knowledge and preventive behaviour relevant to skin cancer in general practice patients in south Australia.

BACKGROUND: There is an 'epidemic' increase in skin cancers worldwide in white-skinned populations. Australia has the highest incidence of skin cancer in the world despite intensive publicity in the last 30 years aimed at prevention. AIM: This study set out to assess risk factors, knowledge and preventive behaviour relevant to skin cancer in general practice patients in South Australia, and to investigate the relationship between risk, knowledge and behaviour. METHOD: A questionnaire on skin cancer was distributed to 980 patients aged 16 years and over attending general practitioners' surgeries in South Australia. A total of 810 questionnaires were analysed (83%). RESULTS: There was a high overall level of knowledge and awareness of skin cancer. However, the majority of respondents were unaware of the risks of blue eyes (87%), fair hair (83%) or red hair (68%). A third of respondents were unaware that having lots of moles and freckles was a risk factor for skin cancer. A considerable minority were unaware of the risk of a fair complexion (26%), getting sunburnt (14%) or prolonged exposure to the sun (11%). Sunscreen cream was the most popular preventive behaviour (use reported by 74%), followed by clothing (54%), shade (16%) and timed sun exposure (13%). The most common number of methods of prevention used was two, but 16% were not able to mention anything that they did to prevent skin cancer. The correlations between presence of risk factors, knowledge and preventive behaviour were poor. CONCLUSION: There was a high overall level of knowledge and awareness of skin cancer in South Australia but despite intense publicity, important areas of ignorance were still found to exist. The simpler methods of skin cancer prevention appeared to be neglected in favour of sunscreen cream. Those at high risk did not know more about skin cancer and reported doing little more to prevent it than those at low risk. There is a need to target those at high risk for education and screening. General practitioners, with adequate training, could have an important part to play in the primary and secondary prevention of mortality and morbidity from skin cancer.

Health Behavior↗
PubMed1995

The relationship between paternal age, sex ratios, and aneuploidy frequencies in human sperm, as assessed by multicolor FISH.

We studied the frequencies of X- and Y-chromosome-bearing sperm, diploidy and disomy for chromosomes 1, 12, X, and Y in sperm from 10 normal men aged 21-52 years, to determine whether there was any relationship between donor age and any of these variables. Multicolor FISH was used to control for lack of probe hybridization and to distinguish diploid sperm from disomic sperm. A minimum of 10,000 sperm per donor was evaluated for each chromosome, for a total of 225,846 sperm studied. Sperm were considered disomic if two fluorescent signals were separated by a minimal distance of one signal domain. The mean frequencies of X- and Y-bearing sperm were 50.1% and 49.0%, respectively; not significantly different from 50%. There was no correlation between paternal age and "sex ratio" in sperm. Similarly, there was no association between the frequency of diploid sperm (mean, .16%; range, .06-.42%) and donor age. For disomy frequencies, there was no relationship between donor age and disomy 12 (mean, .16%; range, .10%-.25%), XX (mean, .07%; range, .03%-.17%), and XY sperm (mean, .16%; range, .08%-.24%). There was a significant increase in the frequency of YY sperm (P = .04; mean, .18%; range, .10%-.43%) and disomy 1 sperm (P = .01; mean, .11%; range, .05%-.18%) with donor age. In summary, our results do not support a correlation between paternal age and sex ratio or diploidy.

Adult↗
PubMed1994

Analysis of segregation in a human male reciprocal translocation carrier, t(1;11) (p36.3;q13.1), by two-colour fluorescence in situ hybridization.

Using centromeric probes specific for chromosomes 1 and 11, 13,071 sperm nuclei from a male reciprocal translocation heterozygote, 46,XY,t(1;11) (p36.3;q13.1), were analyzed by fluorescence in situ hybridization (FISH). Decondensed sperm nuclei were simultaneously hybridized with DNA probes for chromosome 1 (pUC177) and chromosome 11 (D11Z1). Results were as follows: 1/11 (82.45%), 1/1/- (3.45%), -/11/11 (4.85%), 1/1/11 (1.20%), 1/11/11 (1.14%), 1/- (4.33%), -/11 (2.50%), 1/1/11/11 (0.06%), 1/1/1/- (0.02%). Because both the normal chromosome and its translocated derivative carry the same centromeric sequences, FISH cannot differentiate between sperm resulting from alternate segregation and those produced by adjacent I segregation. Using the same donor, comparable segregation patterns were obtained from sperm chromosome karyotypes (Spriggs et al., 1992: Hum Genet 88:447-452) and from MII spermatocytes (Goldman and Hulten, 1993: Cytogenet Cell Genet 63:16-23), demonstrating that selection is not a factor in the human sperm/hamster oocyte fusion technique or during meiosis. Although FISH does not provide the detailed information afforded by sperm karyotyping, it is a valuable technique for studying segregation patterns in translocation heterozygotes.

Cell Nucleus↗
PubMed1994

Analysis of sperm chromosome complements from a man heterozygous for a pericentric inversion of chromosome 1.

Human sperm chromosomes were studied in a man heterozygous for a pericentric inversion of chromosome (1)(p31q12). Q-banded pronuclear chromosomes were analyzed after in vitro penetration of golden hamster oocytes. A total of 159 sperm were examined: 54% bearing the inverted chromosome 1 and 46% the normal chromosome 1. These frequencies are not significantly different from the theoretical 1:1 ratio. There were no recombinant sperm with duplications or deficiencies, suggesting that a pairing loop failed to form or that crossing-over was suppressed. The frequency of abnormalities unrelated to the inversion was 5% for numerical, 8.8% for structural, 2.5% for numerical and structural, values not significantly different from control donors studied in our lab. The frequencies of X- and Y-bearing sperm were 46% and 54%, respectively, not significantly different from the expected value of 50%. This is the fifth pericentric inversion studied by human sperm chromosome analysis; recombinant chromosomes have been observed in two of the five cases. Some of the factors associated with an increased risk of recombinant sperm appear to be inversion size greater than 30% of the chromosome and chromosome breakpoints in G-light bands.

Adult↗
PubMed1994

Sperm chromosome complements in a man heterozygous for a reciprocal translocation t(2;3)(q24;p26).

Sperm chromosome complements were studied in a man heterozygous for a reciprocal translocation t(2;3)(q24;p26). This man was identified during a family study after his sister was investigated for amenorrhea. A total of 92 spermatozoa were karyotyped after in-vitro penetration of hamster eggs. The frequencies of alternate, adjacent 1, adjacent 2 and 3:1 segregations were 55.4, 36.1, 7.2 and 1.2% respectively. For alternate segregations, the number of normal spermatozoa (n = 25) was not significantly different from the number of spermatozoa carrying a balanced form of the translocation (n = 21), as theoretically expected. The proportion of spermatozoa with an unbalanced form of the translocation was 44.6%. There was no evidence for an interchromosomal effect since the frequencies of numerical and structural abnormalities (unrelated to the translocation) were within the normal range of control donors.

Adult↗
PubMed1994

Detection of aneuploidy in human sperm by fluorescence in situ hybridization (FISH): different frequencies in fresh and stored sperm nuclei.

Fluorescence in situ hybridization (FISH) with chromosome-specific repetitive DNA probes provides a new method for rapid detection of aneuploidy in human sperm. There is widespread interest in this technique for basic research, as well as for screening men exposed to potential aneugens. A number of laboratories have reported a wide range in the frequency of aneuploidy for chromosomes in human sperm, suggesting that FISH may not reflect the true frequency accurately. We have serendipitously discovered that the length of time that fixed frozen sperm nuclei are stored affects both the hybridization efficiency and disomy frequency of individual chromosomes. This may explain some of the variation in the aneuploidy frequencies observed among laboratories.

Aneuploidy↗
PubMed1994

Chromosomal breakage in human spermatozoa, a heterozygous effect of the Bloom syndrome mutation.

The chromosome complements of 662 spermatozoa produced by the three fathers of individuals with Bloom syndrome (BS) were analyzed to determine whether the BS mutation could affect chromosome segregation and the frequency of aneuploidy in sperm. The frequency of numerical abnormalities was not significantly different from that in normal controls studied in our laboratory, but the frequencies of structural abnormalities were significantly increased in two of the men, 14.3% and 15.9%, versus 8.6% in controls. More striking was the increase in these two men of cells with multiple structural abnormalities: 8.1% and 6.7% with multiple abnormalities, versus 2.3% in controls.

Abnormalities, Multiple↗
PubMed1994

Assessment of painful late effects of lumbar spinal fusion with SPECT.

UNLABELLED: The authors reviewed planar, SPECT and other contemporaneous radiologic images of the spine and the medical records of 33 patients with back pain after lumbar fusion surgery in order to determine the value of SPECT in the assessment of painful late effects of spinal fusion surgery. METHODS: Twenty-one patients had lateral fusion, nine patients had posterior fusion only and three patients had anterior and posterior fusions. There were 24 patients who had surgery more than 4 yr ago (late group, mean 11.8 yr) and 9 patients who had surgery less than 4 yr ago (early group, mean 17.8 mo). RESULTS: The most common SPECT abnormality in patients in the late group were lesions in the vertebral bodies and apophyseal joints in the free motion segments adjacent to the fused segments (62.5% of patients). Such lesions occurred in 46% of patients after lateral fusion, in 87.5% of patients after posterior fusion and in 67% of patients after posterior and anterior fusions. No SPECT abnormalities were detected in the fused segments in patients in the late group with solid lateral fusion but were detected in three patients with solid posterior fusion. These results correlate with biomechanical studies that have shown posterior fusion to produce the largest amount and lateral fusion to produce the least amount of stress in the free segments adjacent to the fusion. Lateral fusion was found to have a more stabilizing effect than posterior fusion. CONCLUSION: In addition to the already established value of SPECT in detecting painful pseudoarthrosis, our results indicate that SPECT is of value in the assessment of painful late effects of fusion.

Adult↗
PubMed1994

Indium-111-white blood cell scintigraphy in Crohn's patients with fistulae and sinus tracts.

METHOD: Indium-111-white blood cell (111In-WBC) images of 17 Crohn's patients with fistulae and sinus tracts were reviewed and correlated with radiographic results (n = 16 patients) and surgery (n = 16 patients), to characterize the scintigraphic appearance of fistulization and to determine the role of 111In-WBC scintigraphy in this clinical setting. These were compared to 50 consecutive abnormal 111In-WBC studies obtained in Crohn's patients with suspected active disease but no known fistulae or sinus tracts. RESULTS: Scintigraphic findings which suggested the presence of fistulae were: (1) the presence of concomitant intestinal and extraintestinal lesions and (2) the absence of luminal activity on delayed images when early images detected bowel activity. The extraintestinal lesions were the drainage site of the fistula (n = 7) or an accompanying abscess (n = 6). Absence of luminal activity occurred in seven patients with fistulae and in two without fistulae; two patients had a proximal colostomy, two patients had bowel obstruction and five patients had fistulae to the skin (n = 3) or between the ileum and distal colon (n = 2). The distribution of active bowel disease as assessed scintigraphically was in complete agreement with surgery in 14 of 17 cases (82%) compared to 9 of 15 cases (60%) when correlating radiographic assessment with surgery. All surgically proven abscesses were detected on 111In-WBC images. CONCLUSION: These results indicate that 111In-WBC scintigraphy adds useful information to radiographic studies that is essential for appropriate management of Crohn's patients with fistulae and sinus tracts.

Adult↗
PubMed1993

Aneuploidy detection in human sperm nuclei using fluorescence in situ hybridization.

Fluorescence in situ hybridization (FISH) was performed on human interphase sperm nuclei to determine the utility of this technique for aneuploidy detection. Repetitive DNA sequences specific for chromosomes 1, 12 and X were biotinylated and hybridized with mature sperm, which had been treated with cetyltrimethylammonium bromide and dithiothreitol to render them accessible to the probes. Detection of bound probe was accomplished with fluoresceinated avidin and antiavidin. For each of the chromosomes studied, chromosome number was determined by counting the fluorescent signals, representing hybridized regions, within the sperm nuclei. The frequencies for disomy, that is for nuclei containing two signals, for chromosomes 1, 12 and X were 0.06%, 0.04% and 0.03%, respectively. The congruence of these results with those determined by the cross-species hamster oocyte-human sperm assay, and the high efficiency of hybridization indicate that FISH is a sensitive and reliable tool for aneuploidy detection in human sperm.

Aneuploidy↗
PubMed1993

Detection of genetic damage in human sperm.

Assessment of genetic damage in human sperm is now possible using the hamster oocyte/human sperm fusion technique. This cross-species in vitro assay provides precise human sperm karyotypes that can be banded for identification of individual chromosomes and numeric and structural abnormalities. This technique is time-consuming and difficult but there are now 11 laboratories in 7 different countries reporting results on normal men and men at increased risk of sperm chromosomal abnormalities. Men who have been exposed to radiotherapy and chemotherapy have been shown to have an increased frequency of chromosomal abnormalities in their sperm. A few laboratories have reported results on the use of fluorescence in situ hybridization (FISH) of interphase sperm nuclei. This appears to be a promising new technique for the assessment of aneuploidy and FISH results from our laboratory correlate well with our frequency of aneuploidy determined by sperm chromosome analysis. Thus it is possible that, in the future, FISH might be used as a simple rapid screen of potentially aneugenic agents.

Animals↗
PubMed1993

Chromosome complements in 695 sperm from three men heterozygous for reciprocal translocations, and a review of the literature.

Sperm chromosome complements were analysed in three men heterozygous for reciprocal translocations. A total of 695 sperm were karyotyped after in vitro penetration of hamster oocytes: 275 sperm from t(7;20)(q33.2;p13), 268 from t(3;11)(q25.3;q25) and 152 from t(15;22)(q26.1;q11.2). All possible 2:2 and 3:1 meiotic segregations were observed for all three translocations. The frequencies of alternate, adjacent 1, adjacent 2, and 3:1 segregations were 38%, 40%, 16%, and 5% for t(7;20); 48%, 46%, 6%, and 1% for t(3;11); and 34%, 40%, 22%, and 4% for t(15;22), respectively. Within the alternate segregation, the number of normal sperm was not significantly different from the number of sperm carrying a balanced form of the translocation for any of the translocations, as theoretically expected. The percentage of sperm with an unbalanced form of the translocation was 62% for t(7;20), 52% for t(3;11) and 66% for t(15;22). Sperm chromosome complements were observed in all three translocations that could be attributed to crossing-over in the interstitial segment, although nondisjunction at anaphase II could also account for the complements. There was no evidence for an interchromosomal effect in any of the translocations since the frequencies of numerical abnormalities unrelated to the translocation were within the normal range of control donors. Data from a total of 27 reciprocal translocations studied by sperm chromosomal analysis were reviewed.

Adult↗