Biomedical subjects
Publications and source records attributed to J Nash.
Sexual functioning was investigated in 50 parkinsonian male and female patients using a questionnaire. A loss of sexual interest and functioning was reported in a high percentage of patients. Depression was not prevalent but 70% had some evidence of autonomic nervous system dysfunction that may be related to sexual dysfunction. It is concluded that the sexual function is frequently impaired in Parkinson's disease.
The maize Bronze-2 (Bz2) gene, whose product acts late in the anthocyanin biosynthetic pathway, has been cloned and its transcript has been mapped. We have developed a general procedure for reconstructing wild-type alleles from transposable element-induced mutants. An existing transposon-containing clone, bz2::mu1 [McLaughlin, M., and Walbot, V. (1987). Genetics 117, 771-776], was modified by replacing the region of bz2::mu1 containing the transposon with the corresponding polymerase chain reaction-amplified sequence from the progenitor allele that has no Mu insertion. Particle gun delivery of the reconstructed Bz2 gene to embryonic scutellar tissue lacking a functional Bz2 gene complemented the bz2 mutant phenotype, as demonstrated by the production of purple spots. Having cloned the wild-type allele, we then analyzed the Bz2 transcript, whose features include an 82-nucleotide 5'-untranslated leader, one small intron (78 base pairs) within the coding region, and multiple polyadenylation sites. Four Mutator transposon insertions that eliminate gene function were mapped within the 850-nucleotide transcription unit. We found that variable levels of unspliced Bz2 RNA are present in purple husk tissue; this finding may indicate that the expression of Bz2 is regulated in part at the level of transcript processing.
We describe 50 patients with anaplastic carcinoma presenting with a mass in the neck. The diagnosis of anaplastic carcinoma was confirmed by immunocytochemistry to exclude very poorly differentiated squamous carcinomas, amelanotic melanoma, and non-Hodgkin's lymphoma. The primary site was established immediately in 26 patients (25 in the head and neck; 1 in the lung); a further 4 had radiological evidence of a primary tumour in the lung. The primary site was established later in 1 patient, in the ethmoid sinuses. In 20 patients the primary site was never established. The commonest primary site was the nasopharynx. The basic treatment policy was radiotherapy, although 20% of patients with a known primary tumour, and 50% of those without, were untreated. The 2-year survival was about 30% in both groups, and did not differ significantly. Prognostic factors for survival were age, performance status, and T status of the primary tumour. Sex, node status, node level, and laterality of nodes, were not.
Voluntary control of muscle contraction was examined in five adults with cerebral palsy, who were required to track a moving target by continuously varying the level of isometric contraction of elbow flexor muscles (measured by EMG). First performance varied from minimal control to almost normal control, depending on the severity of disability. Practice over 12 weeks reduced inappropriate muscle activity in the most disabled patients, but there was no increase in appropriate muscle activity for any patient beyond that observed after the first few minutes of tracking. Thus their ability to translate a visual response into the appropriate motor activity was impaired, and there was no evidence of potential to overcome this. This supports the authors' earlier proposal that impairment of sensory-motor learning is the primary cause of functional disability in cerebral palsy. The EMG tracking task may provide a technique for assessing the ability of individuals with cerebral palsy to control muscle contraction.
1. Because of the high costs involved in turnover and orientation, the interview process is an integral part of management. 2. Preparation is the most important part of any interview; dress appropriately, ask relevant questions, and know the job description and requirements. 3. Know your own philosophy and respond according to it, not what you perceive to be the "correct" response.
1. In ninety-ninety intraosseous wiring, two 26-gauge intraosseous wires are placed perpendicular to each other through bone. This technique requires slight exposure to obtain rigid fixation, and the patient can expect relatively unhindered rehabilitation using early digit motion. 2. Because the procedure is long and tedious, two surgical teams, each with its own circulating and scrub nurses, are preferred. 3. Ninety-ninety intraosseous wiring is less prominent than plates or screws, it has less risk that adhesions will develop, and, theoretically, less bone is devascularized.
A randomized, placebo-controlled trial was conducted to compare the effects of treatment with prazosin, propranolol, or hydrochlorothiazide on the following variables: blood pressure, cognitive and psychomotor skills, cardiovascular reactivity to natural and laboratory challenges, and serum lipid and lipoprotein levels. Side effects were recorded and patients evaluated how they felt during their treatment. Sixty-nine men, 35 percent black, aged 25 to 55 (mean 51.3) years, with diastolic blood pressures between 90 and 104 mm Hg (mean, 93.3 mm Hg), completed the study. There were no differences between active treatment groups in the proportion of patients with controlled blood pressure during the maintenance phase of the study. In the cognitive and psychomotor tests, the hydrochlorothiazide group showed significantly less improvement from baseline than the other treatment groups on the block design subscale of the Wechsler Adult Intelligence Scale-Revised, and there was a trend for the propranolol group to have less improvement from baseline than the other groups on the digit span subscale. There were no other significant pretreatment to post-treatment changes in the other cognitive or psychomotor tests, the Russell Revision of the Wechsler Memory Scale, or a number of computerized reaction-time and signal-detection tasks. In the reactivity testing, there was a significantly lower increase in heart rate in the prazosin group compared with placebo during the second laboratory challenge of the Stroop Color Interference Test. Post-treatment declines in ambulatory blood pressure were seen in all of the drug treatment groups in average and maximal diastolic and systolic blood pressures. Both propranolol and hydrochlorothiazide treatment resulted in low-density lipoprotein cholesterol levels that were higher than baseline and the hydrochlorothiazide treatment had significantly increased total cholesterol levels. In contrast, the prazosin-treated group experienced no adverse changes in these parameters. Overall, the propranolol group had significantly more moderate and severe side effects than did the other three groups. Considering the pattern of blood pressure control, cognitive and psychomotor effects, changes in lipid levels, and magnitude of side effects, prazosin seems to have the most advantageous profile in this study of the three anti-hypertensive agents evaluated.
Both carotid bodies were obtained at necropsy from each of 75 subjects, 38 male and 37 female, ranging in age from 14 to 90 years. In each case the histological features were classified as one of four age-related patterns. The presence and distribution of lymphocytes were noted. They presented either as a diffuse scattering throughout the stroma or as large focal aggregates. In subjects over the age of 50 years the diffuse infiltrates occurred in 56% of cases and were virtually all T-cells. In the same age group the aggregates of lymphocytes were found in 21% of cases. These findings indicate that there is a disease of human carotid bodies characterized by focal aggregates of lymphocytes that begins in middle age and becomes increasingly common with advancing years, affecting 29% of subjects aged 70 years or over. It is not related to any co-existing disease but seems to be a response to the degenerative changes in the glomic tissues that occur with age. By analogy with comparable changes in the thyroid and salivary glands, the disease may have a basis in auto-immunity.
A biofeedback training technique to control spasticity, previously successful with adults with cerebral palsy, was adapted for three children with spastic diplegia at risk for contractures. Visual feedback of muscle stretch reflex sensitivity is provided by video games, which are played by reducing reflex sensitivity. After a 10-week training period two of the three children had significantly reduced spasticity in the gastrocnemius muscle. The technique can be used with children as young as four years, is inexpensive, and can be carried out by parents with supervision by a physiotherapist.
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There are three types of histological change in the carotid bodies which appear to have physiological and clinical associations. A prominence of the dark variant of chief cells with their contents of met-enkephalin and other peptides appears to be associated with acute exposure to hypoxia. Proliferation of sustentacular cells around the clusters of chief cells appears to be related to ageing and also to systemic hypertension. Recently we have described a new condition of chronic carotid glomitis which is characterized by follicles of lymphocytes and may have a basis in auto-immunity. In the present review we report for the first time plasma cell activity in the carotid bodies of an elderly man, especially around nerve fibrils and unmyelinated axons ensheathed in sustentacular cells. Such appearances are consistent with the view that ageing nerve fibrils may be the antigenic stimulus for the development of chronic carotid glomitis.
Because caffeine might be harmful to the fetus, the Food and Drug Administration of the United States recently urged that "pregnant women should avoid caffeine-containing food and drugs, if possible, or consume them sparingly". In this paper, the potential reproductive and teratological risks of caffeine are briefly reviewed.
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Transposon Tn7 insertions in the origin of vegetative replication (oriV) result in host range mutants of the promiscuous IncP-1 plasmids R18 and R68 which affect plasmid replication in Escherichia coli but not in Pseudomonas aeruginosa. The sites of these insertions have been analyzed by DNA sequence analysis. In two mutants, the insertions generated direct duplications of 5'GTATT3' at the target site which included the first base at the 5' end of the fourth 17-bp direct repeat in oriV. In a third mutant the duplication of 5'GACAC3' also involved the same direct repeat also at the 5' end but contiguous with the previous duplication. DNA sequence analysis of another Tn7-induced host range mutant of R18, characterized by reduced conjugational transmissibility into P. stutzeri while retaining normal transmissibility within P. aeruginosa, showed that the insertion generated a 474-bp deletion which brought the insertion 20 bp 5' to the 17-bp direct repeat between oriV and the oxytetracycline hydrochloride-resistant gene. The analysis of the DNA sequence data at the site of the Tn7 insertions shows that particular segments of the DNA sequence in oriV are differentially required for the replication of these plasmids in different bacterial hosts and thus of importance to the promiscuity of these plasmids.
Environmental and occupational health problems cannot be understood through purely medical and epidemiological analyses, the social forces affecting biologically adaptive behavior must also be analyzed. Research on the political economy of health needs to generate an ethnology of community action relevant to the analyses of corporate structures for which it is best known. In studying the community of Pittsfield, Mass., where a General Electric plant is located, we encountered environmental and occupational health problems in just this context. This essay is, therefore, an effort to extend the political economy of health into the ethnological domain of community research.
Fifty-one host range mutants of the promiscuous plasmid R18 were isolated by Tn7 insertion mutagenesis by using Pseudomonas aeruginosa as the permissive, and P. stutzeri as the nonpermissive, host. Endonuclease cleavage mapping of 40/51 mutants showed that 37 mutations mapped to kilobase coordinates 40.3-43.8 in the two overlapping genes encoding plasmid DNA primase. Thus by this procedure it has been possible readily to isolate a large number of primase mutants. The majority of these mutations mapped to the overlapping DNA whereas a few also mapped to the nonoverlap region encoding the larger 118-kDa polypeptide. Among these mutants were four which had long deletions within the overlapping segment and extending to varying lengths anticlockwise of it. The genetic defect in these mutants has been correlated with greatly reduced in vitro primase enzyme activity. The primase mutations drastically affected the mutant's ability to mobilize a nonconjugative, wide-host-range IncP-4(Q) plasmid from P. aeruginosa to P. stutzeri although mobilization within P. aeruginosa was affected to a lesser degree. Other insertion mutations were mapped to the regions of plasmid origin of transfer (oriT) and origin of replication (oriV), but their physical location was different to previously identified similar mutations obtained using Escherichia coli as the nonpermissive host. Their physically distinct locations were correlated with differences in their transmissibility from P. aeruginosa into enteric bacterial species and into other Pseudomonas species.
The traditional and predominant manner of delivering dental care is through a fee-for-service, private practice system. A number of alternative dental care delivery systems have emerged and are being tested, and others are just emerging. These systems include department store practices, hospital dental services, health maintenance organizations, the independent practice of dental hygiene, and denturism. Although it is too soon to draw final conclusions about the efficacy and effectiveness of these systems, we examine them for their potential to compete with and change the way dental care is currently delivered. Using the parameters of cost, accessibility, and quality, we compare these systems to traditional dental practice. Some of these emerging forms clearly have the potential to complete favorably with traditional practice. Other seem less likely to alter the existing system substantially. The system which can best control costs, increase accessibility, and enhance quality will gain the competitive edge.
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