Biomedical subjects

B S Mahoney

Publications and source records attributed to B S Mahoney.

9 recordsLinked to original sources

PubMed1996

Preimplantation genetic testing for Marfan syndrome.

Marfan syndrome (MFS) is an autosomal dominant disease that affects the skeletal, ocular and cardiovascular systems. Defects in the gene that codes for fibrillin (FBN-1) are responsible for MFS. Here we report the world's first use of preimplantation genetic testing (PGT) to achieve a clinical pregnancy and live birth of a baby free of a Marfan mutation. One or two blastomeres from each embryo were tested for a CA repeat within the FBN-1 gene. The prospective mother is homozygous for the CA repeat (2/2) and has two normal copies of the FBN-1 gene, while the prospective father is heterozygous for the CA repeat (1/2), and is affected with the Marfan syndrome. In the father's family, allele 2 segregates with the mutated FBN-1 gene. For PGT, any embryo diagnosed as heterozygous for the CA repeat (1/2) would be presumed to have inherited normal FBN-1 genes from the father and the mother and be unaffected. One in-vitro fertilization (IVF) cycle yielded 12 embryos for preimplantation testing; six of the embryos were heterozygous for the CA repeat (1/2) and presumed to be free of the Marfan mutation. Five of the six embryos were subsequently transferred into the uterus. The fetus was tested by chorionic villus sampling and found to be free of the Marfan mutation by the same linkage analysis, had a normal fetal echocardiogram, and was normal at birth.

Adult↗

PubMed1993

The effects of high and low BACs on the Hoffmann reflex.

The purpose of this study was to measure and assess the magnitude and latency of the H-reflex and M-response between pre- and post-alcohol consumption. Also of interest was the comparison of the H-reflex and M-response between the rising and falling curves of BAC. Seven male volunteer subjects participated in this study. Testing started with pre-alcohol BAC and EMG recordings from the tibial nerve following an electrical stimulation. After alcohol consumption, BAC readings were obtained every five minutes, and the EMGs were recorded at the following BAC levels (in mg/dl): 75, 100, and falling 75. H-latency, H-amplitude, and M-response were identified within the EMG signals. The analysis focused on the comparisons of these measures between each of the BAC levels and the baseline, as well as between the rising and falling BACs. Results showed that, overall, the H-reflex and M-response were depressed following alcohol consumption. In addition, the depression of H-reflex appeared to be greater during the rising curve than the falling curve.

Adolescent↗

PubMed1993

A proposed classification code for farm and agricultural injuries.

A fundamental problem with classifying agriculturally related injury is that there is neither a rational nor a comprehensive scheme for grouping incidents into categories describing actual exposures encountered on farms and in agricultural work. Current surveillance systems are unable to differentiate between work that is related to farm production and work that is not, and to include all exposed persons in the surveillance. The proposed Farm and Agricultural Injury Classification Code is a step toward overcoming these problems. When it was applied to previously analyzed fatality data, 40% of cases previously identified as farm production work were reclassified into other categories.

Agricultural Workers' Diseases↗

PubMed1993

Proprioceptive responses under rising and falling BACs: a test of the Mellanby effect.

This study examined proprioceptive responses under equivalent rising and falling blood alcohol concentrations (BAC), using a repeated-measures design. Seven volunteer subjects, 21 to 35 years of age, participated in the study. After alcohol consumption, BAC readings were obtained every 5 minutes, and the proprioceptive responses were measured at the following BAC levels (in %): 0 (baseline), rising 0.05, 0.075, 0.1, falling 0.075, and 0.05. The analysis focused on the comparisons of these measures at the equivalent rising and falling 0.05% and at the 0.075% BACs. Results showed that the proprioceptive response was less accurate during the rising than the falling BACs.

Adolescent↗

PubMed1992

Predicting alcohol impairment: perceived intoxication versus BAC.

The purpose of this study was to report the relationship among perceived intoxication, performance impairment, and actual blood alcohol concentration (BAC) levels. Fifteen subjects, aged 21 to 40, completed both single- and double-dose sessions of alcohol consumption. BACs, reaction and anticipation time, and perceived intoxication data were collected during both sessions. Analysis of data showed that perceived intoxication was significantly related to performance impairment, but the actual BAC was not.

Adult↗

PubMed1992

Survey of health promotion in Pennsylvania nursing homes.

Health promotion programs for residents represent a discretionary organizational response to increased demand for service differentiation within the nursing home setting. More than half (57%) of facilities in a systematic sample of Pennsylvania nursing homes reported offering one or more health promotion programs. This article describes the variety of topical categories of programs. Guided by two alternative explanations of medical technology adoption--the key professional model versus the institutional/environmental model--an explanation is offered about why some facilities offer such programs and others do not.

Evaluation Studies as Topic↗

PubMed1992

Variability in behavioral impairment involved in the rising and falling BAC curve.

The purpose of this pilot study was to measure variability in behavior impairment at specific levels of the rising and falling blood alcohol concentration (BAC) curve. Behavior impairment was measured for anticipation and reaction time in addition to a variety of visual skills. Also of interest was the variability in impairment involved at specific BAC levels under single-dose and double-dose conditions. The experimental design was a variation on a 2 x 2 factorial with repeated measures on the dose of alcohol. All subjects took part in two experimental sessions, single-dose and double-dose. Sixteen (8 male and 8 female) paid subjects ages 21-40 participated in the study. Testing procedures included repeated measures on reaction time, anticipation time, perceptual vision acuity and depth perception. Breath-alcohol measures were sampled continuously at 5-minute intervals and used to plot absorption time, peak BAC and elimination time. Results showed that the average peak BAC for the double-dose was significantly higher than that of the single-dose condition. However, there were no significant differences between the single-dose and double-dose condition in either absorption time or elimination time. The performance pattern for reaction time, anticipation time and depth perception showed more impairment in the rising BAC limb than in the falling BAC limb. It is noteworthy that specific individuals exhibited different levels of impairment at a given BAC level, depending on whether the session was single- or double-dose, suggesting that one's current BAC level is less a measure of impairment than is the total quantity of alcohol consumed. A follow-up procedure to examine practice effects was conducted on eight volunteer students. Identical testing procedures, using no alcohol, produced no significant practice effects after a 3-hour period.

Adult↗

PubMed1992

Psychomotor and visual performance under the time-course effect of alcohol.

This study examined reaction time (RT), anticipation time (AT), and visual performance under the influence of blood alcohol concentration (BAC), using a repeated-measures design. Subjects (8 men and 8 women), 21 to 40 yr. of age, participated in both single- and double-dose sessions, in which they drank approximately 2.3 oz. and 4.6 oz. of 86-proof vodka, respectively. The breath BAC was measured at 5-min. intervals. The RT, AT, and visual performance were tested every 20 min. for 140 min. in both sessions. In general, results indicated that RT, AT, and stereoscopic vision were impaired more in the rising BAC curve than the falling BAC curve. In addition, the impairment tended to be greater for the double-dose than the single-dose session. The far and near visual acuities were not affected by the BAC.

Adult↗

PubMed1991

The extent, nature, and response to victimization of emergency nurses in Pennsylvania.

A survey of 124 emergency departments documents the existence of significant victimization of emergency nurses. Data reflect an increased incidence of violence associated with urban settings, night shifts, shifts more than 8 hours long, patients who are intoxicated, patients who have medical conditions such as dementia or cerebral trauma, and male emergency nurses. After victimization, almost 15% of responding nurses had considered transferring to another unit; almost 18% had considered leaving nursing altogether.

Adult↗