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Biomedical subjects

J Martin

Publications and source records attributed to J Martin.

At least 415 records · Page 23Linked to original sources
PubMed1996

Finger flexion does not contribute to ball speed in overarm throws.

The aim of this study was to determine whether, in overarm throws made by recreational ball players, the fingers undergo flexion movement before ball release and thereby contribute to the generation of ball speed. To obtain the high resolution needed to answer this question, the magnetic-field search-coil technique was used and the data were sampled at 1000 Hz. The subjects, who were either seated or were standing, threw tennis balls at different speeds at a target 3 m away. Angular positions in three dimensions were simultaneously recorded of the distal phalanx of the middle finger and hand and, in additional experiments to determine the mechanism of ball release in more detail, three middle finger phalanges and the hand. Different phases of ball release were determined by pressure-sensitive microswitches on the proximal and distal phalanges of the middle finger. Irrespective of whether the subjects were seated or were standing, for all throws at all speeds, finger flexion did not occur before ball release. That is, up until final release of the ball, the fingers only underwent extension associated with hand opening. For fast throws, at the instant of final ball release the fingers began to flex, presumably as a result of reactive forces associated with release of the ball. Thus, in overarm throws made by recreational ball players, finger flexion movement does not appear to contribute to the generation of ball speed.

Adult↗
PubMed1996

A longitudinal trial of weight training in the elderly: continued improvements in year 2.

We conducted a 2-year (42 weeks of consecutive training in each year, separated by 10 weeks of testing and vacation time) randomized, controlled trial of weight training in 142 healthy male and female subjects, aged 60 to 80 years. Measurements included dynamic strength, symptom-limited endurance in cycling, treadmill walking and stair climbing, muscle size, and bone mineral density and content of the lumbar spine and whole body. One hundred and thirteen subjects completed the study (57 exercise, 56 control), with a mean attendance of 85% among the exercisers. Muscle strength was unchanged in the control subjects but increased (collapsed across age and gender) from 32% (leg press) to 90% (military press) in the exercisers. Symptom-limited endurance in cycling, treadmill walking, and stair climbing increased in the exercisers by (mean +/- SE) 6.2 +/- 0.8%, 29.2 +/- 7.3%, and 57 +/- 12%, respectively; the only change in the controls was an unanticipated 33% increase in stair climbing performance during the first year. These values were unchanged in the controls. Cross-sectional area of the knee extensors increased by 8.7 +/- 0.9% in the trained subjects and was unchanged in controls. Measures of whole body, lumbar spine bone mineral density, and lumbar spine bone mineral content were unchanged in the exercisers, but whole body bone mineral content decreased by 1%. In contrast, there were small increases (< 4.0%) in bone mineral density among the controls. Long-term weight training proved to be a safe and well-tolerated mode of exercise for the elderly. Increased strength was associated with muscle hypertrophy in each year, and with increased endurance in cycling, walking, and stair climbing. There were no changes in bone mineral density but a small reduction in whole body bone mineral content.

Aged↗
PubMed1996

Validation of an objective structured assessment of technical skill for surgical residents.

PURPOSE: This study examined the concurrent validity of the Objective Structured Assessment of Technical Skill (OSATS), a new test of technical skill for general surgery residents. METHOD: Twelve residents (six in their senior, or fifth, year and six in their junior, or third, year) at the University of Toronto in 1994-95 were ranked within level of training according to their OSATS marks and by surgical faculty. Correspondence between OSATS and faculty rankings was assessed using Spearman rank-order correlation coefficients. RESULTS: The correlations between test scores and faculty rankings were generally high for the senior residents but low for the junior residents. CONCLUSION: Scores on the OSATS accurately reflect the independent opinions of faculty regarding the technical skills of senior residents, suggesting that it is a valid measure of technical skill for these individuals. The scores did not, however, reproduce faculty rankings of the junior residents. Whether this was a failing of the OSATS or the faculty rankings requires further study.

Clinical Competence↗
PubMed1996

Fluoxetine treatment of children with selective mutism: an open trial.

OBJECTIVE: A pilot study was designed to evaluate the safety and efficacy of fluoxetine treatment for children with selective mutism (elective mutism in DSM-III-R). METHOD: Twenty-one children (mean age 8.2 years, range 5 through 14) participated in a 9-week open trial of fluoxetine in graduated doses (mean end dose 28.1 mg, range 10 to 60 mg) with systematic baseline and outcome evaluations and weekly clinical assessment. RESULTS: All 21 children met DSM-III-R and DSM-IV criteria for anxiety disorders. After fluoxetine treatment, 76% were improved, with diminished anxiety and increased speech in public settings, including school. Improvement at week 9 was inversely correlated with age. CONCLUSIONS: Persistent selective mutism presenting with comorbid anxiety disorders may respond to fluoxetine treatment.

Adolescent↗
PubMed1996

Primary pancreatic non-Hodgkin's lymphomas.

Primary pancreatic lymphomas are rare. We reviewed our experience at King Faisal Specialist Hospital and Research Center; the hospital tumor registry identified five patients with primary pancreatic lymphoma among the 1,212 adult non-Hodgkin's (NHL) cases referred to this institute during 1987-1994. The histology was diffuse large cell in all cases. According to the Ann Arbor classification, four patients had stage IE and one patient stage IIE disease. The diagnosis was established by laparotomy in three and ultrasound or CT-guided biopsy in two patients. All patients received chemotherapy. Radiotherapy was used in two cases; in one patient the pancreatic bed was irradiated, whereas in the other radiation was given for obstructive jaundice. Four patients are alive with no evidence of disease at 84, 26, 24, and 21 months follow-up. One patient relapsed at 12 months following chemotherapy and is alive with disease at 23 months follow-up. The clinical and radiological findings in primary pancreatic NHL are not pathognomonic, and the diagnosis is only established on histopathological examination. The management should be nonsurgical as the response to chemotherapy and radiation appears to be no different from NHL at other sites.

Adult↗
PubMed1996

Issues inherent in measuring the impact of care coordination on pregnancy outcomes.

Care coordination is a Medicaid benefit designed to help low-income women gain access to pregnancy-related services. Measuring the outcomes of care coordination is hampered because experimental designs are difficult to carry out on entitlement programs. The purpose of this study was to examine whether a care coordination-adequacy index, based on number of home visits, onset of home visits, and weeks' gestation at delivery, would outperform a simple count of the number of home visits in predicting birthweight. Data from a pilot project in Indianapolis were used. The adequacy index outperformed "number of home visits" in the prediction of birthweight with this sample. Those who received intermediate level of care coordination delivered infants weighing 162 g more than those who received inadequate care coordination. The adequate level of care coordination did not predict birthweight, which may have resulted from an insufficient number of participants in this category (n = 20). An inherent selection bias based on the length of gestation when admitted to the program is also discussed. Research on care coordination with clear delineation of the measurement issues involved must continue to ensure effective program design and continued funding.

Adolescent↗
PubMed1996

Dementing illnesses in rural populations: the need for research and challenges confronting investigators.

Expansion of the world's elderly populations has increased concerns about aging-related medical disorders like Alzheimer's disease and other dementias. In the United States, one fourth of those older than age 65 and at greatest risk for developing dementia live in rural environments that may influence its manifestation. The objectives of this study were to determine the need for and potential benefits of further epidemiological research concerning dementia and similar disorders in rural U.S. populations and to identify pertinent methodological issues related to rural dementia research. This study employed a National Library of Medicine (MEDLINE) document search based on the key words "cognitive disorders," "dementia," "Alzheimer's disease," and "rural," followed by recovery of literature resources references in the bibliographies of selected articles. Nineteen studies focusing on dementia or related disorders in rural settings have been reported from around the world. While four of these were conducted in the United States, only one rural dementia prevalence study has been undertaken in this country. Because of methodological variability, comparisons of prevalence estimates between these rural studies, as well as with those from urban investigations, is difficult. Nonetheless, there is reason to believe that certain potentially dementing illnesses are more common in rural populations. There is also evidence to suggest that the screening instruments commonly used in such studies tend to misclassify rural elders as "false positive" dementia cases. Information regarding dementing disorders, particularly Alzheimer's disease, in rural populations is scarce. Preliminary observations that dementia may be more common in rural settings and that rural families are more likely to maintain their dementing elders in the community imply that further rural dementia research could yield important insights into the risk factors for these illnesses, the variables influencing their course, and the methods by which they can be more effectively managed. A determination of the reliability and validity of commonly used dementia screening instruments in rural populations would represent an important advancement in this area of research.

Adaptation, Psychological↗
PubMed1996

Allelic exchange in Mycobacterium tuberculosis with long linear recombination substrates.

Genetic studies of Mycobacterium tuberculosis have been greatly hampered by the inability to introduce specific chromosomal mutations. Whereas the ability to perform allelic exchanges has provided a useful method of gene disruption in other organisms, in the clinically important species of mycobacteria, such as M. tuberculosis and Mycobacterium bovis, similar approaches have thus far been unsuccessful. In this communication, we report the development of a shuttle mutagenesis strategy that involves the use of long linear recombination substrates to reproducibly obtain recombinants by allelic exchange in M. tuberculosis. Long linear recombination substrates, approximately 40 to 50 kb in length, were generated by constructing libraries in the excisable cosmid vector pYUB328. The cosmid vector could be readily excised from the recombinant cosmids by digestion with PacI, a restriction endonuclease for which there exist few, if any, sites in mycobacterial genomes. A cosmid containing the mycobacterial leuD gene was isolated, and a selectable marker conferring resistance to kanamycin was inserted into the leuD gene in the recombinant cosmid by interplasmid recombination in Escherichia coli. A long linear recombination substrate containing the insertionally mutated leuD gene was generated by PacI digestion. Electroporation of this recombination substrate containing the insertionally mutated leuD allele resulted in the generation of leucine auxotrophic mutants by homologous recombination in 6% of the kanamycin-resistant transformants for both the Erdman and H37Rv strains of M. tuberculosis. The ability to perform allelic exchanges provides an important approach for investigating the biology of this pathogen as well as developing new live-cell M. tuberculosis-based vaccines.

Alleles↗
PubMed1996

Women's self-esteem: a community study of women who report and do not report childhood sexual abuse.

BACKGROUND: The determinants of self-esteem have been little studied in non-clinic samples. It has been suggested recently that child sexual abuse (CSA) may be a major determinant of low self-esteem in adulthood. METHOD: The psychosocial circumstances associated with low self-esteem in two random samples of women, one reporting CSA, the other not, were compared, with particular emphasis on characteristics of family of origin. A two-phase (postal-then-interview) random community study assessed self-esteem and related variables. RESULTS: Psychosocial variables predicting low self-esteem were the same in the two groups. They included being a follower or a loner, having an overcontrolling mother, being poorly qualified, giving a history of depressive disorder and displaying current psychiatric disorder. In addition, the subject's CSA status led to low self-esteem but only when it was of the most intrusive type. The CSA women had substantially lower mean total self-esteem score. However, not all aspects of self-esteem were diminished equally; 12/30 items differed between the two groups, and two of the five generated self-esteem factors, which we named Pessimism and Fatalism, which differed between the control group and the whole CSA group. There were no differences for Likeability and Determination. CONCLUSIONS: Predictors of low self-esteem for women include childhood temperament, a poor relationship with the mother, low qualification attainment, psychiatric morbidity, both previous and current, and, only when it is the most intrusive, CSA.

Adult↗
PubMed1996

Phase I/II study of combined granulocyte colony-stimulating factor and granulocyte-macrophage colony-stimulating factor administration for the mobilization of hematopoietic progenitor cells.

PURPOSE: To study the toxicity and efficacy of combined granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) administration for mobilization of hematopoietic progenitor cells (HPCs). MATERIALS AND METHODS: Cohorts of a minimum of five patients each were treated subcutaneously as follows: G-CSF 5 micrograms/kg on days 1 to 12 and GM-CSF at .5, 1, or 5 micrograms/kg on days 7 to 12 (cohorts 1, 2, and 3); GM-CSF 5 micrograms/kg on days 1 to 12 and G-CSF 5 micrograms/kg on days 7 to 12 (cohort 4); and G-CSF and GM-CSF 5 micrograms/kg each on days 1 to 12 (cohort 5). Ten-liter aphereses were performed on days 1 (baseline, pre-CSF), 5, 7, 11, and 13. Colony assays for granulocyte-macrophage colony-forming units (CFU-GM) and erythroid burst-forming units (BFU-E) were performed on each harvest. RESULTS: The principal toxicities were myalgias, bone pain, fever, nausea, and mild thrombocytopenia, but none was dose-limiting. Four days of treatment with either G-CSF or GM-CSF resulted in dramatic and sustained increases in the numbers of CFU-GM per kilogram collected per harvest that represented 35.6 +/- 8.9- and 33.7 +/- 13.0-fold increases over baseline, respectively. This increment was attributable both to increased numbers of mononuclear cells collected per 10-L apheresis and to increased concentrations of progenitors within each collection. The administration of G-CSF to patients already receiving GM-CSF (cohort 4) caused the HPC content to surge to nearly 80-fold the baseline (P = .024); the reverse sequence, ie, the addition of GM-CSF to G-CSF, was less effective. The CFU-GM content of the baseline aphereses correlated with the maximal mobilization achieved (r = .74, P = .001). CONCLUSION: Combined G-CSF and GM-CSF administration effectively and predictably mobilizes HPCs and facilitates apheresis.

Adolescent↗
PubMed1996

No effect of 96-hour paclitaxel infusion in patients with relapsed non-Hodgkin's lymphoma refractory to a 3-hour infusion schedule.

PURPOSE: Preclinical data suggest that the efficacy of paclitaxel (Taxol; Bristol-Myers Squibb Co, Princeton, NJ) is schedule-dependent. Schedule dependency is currently under investigation in ongoing randomized trials. PATIENTS AND METHODS: Twelve patients with relapsed non-Hodgkin's lymphoma (NHL) refractory to a 3-hour infusion of 200 mg/m2 Taxol were crossed over to receive a 96-hour infusion of 140 mg/m2 Taxol every 3 weeks in an outpatient setting. Premedication with corticosteroids and antihistamines was not used. Patients who did not achieve at least a partial remission (PR) after two courses or whose disease progressed after one course were removed from the study. RESULTS: All 12 patients were assessable for response. Eleven patients received at least two courses and one patient received one course of 96-hour Taxol infusion. None of the 12 patients crossed over to receive 96-hour Taxol infusion achieved a PR or complete response (CR). Eight patients (67%) developed progressive lymphoma, three (25%) had stable disease, and only one (8%) had a minor response. No major hypersensitivity reactions or life-threatening toxicities were observed. CONCLUSION: Ninety-six-hour Taxol infusion does not produce significant responses in patients with NHL refractory to 3-hour Taxol infusion. Until the results of an ongoing multicenter trial comparing a 3- with a 96-hour infusion are published, the use of 96-hour Taxol infusion in NHL patients should be restricted to investigational programs. Because 48- to 72-hour infusions can produce higher plasma concentrations of Taxol than a 96-hour infusion, these schedules should be investigated to determine if they can induce better clinical responses.

Adult↗
PubMed1996

Gender, gender role, and drawing skill.

Separate bodies of research suggest that performance in spatial reasoning covaries with gender and with gender role. Typically studies employ a spatial task whose variance is then used to account for differences in scores between gender groups or variance in a measure of gender role. A methodological issue in such research is that the tasks used to represent spatial reasoning may be differentially available or differentially appealing as a function of gender. Also, authors tend to analyze data in terms of either gender or gender role but rarely both. A collection of personality assessments administered to 204 college students each contained a completed Minnesota Multiphasic Personality Inventory (MMPI-2) and a drawing of a human figure. Within MMPI-2 are three measures of gender role. Drawing talent is unquestionably spatial and has the advantage of being equally available and encouraged among the two genders. Male gender predicted drawing skill. Within both genders, self-perceived masculinity in gender role also predicted higher scores on the drawing skill. Outcomes are seen as compatible with Geschwind and Galaburda's 1987 formulation regarding the behavioral manifestations of fetal androgenization.

Adult↗
PubMed1996

[Vaginal hysterectomy. Role of laparoscopic preparation. Our experience].

The aim of this publication is to define the indications of laparoscopically prepared vaginal hysterectomy. Vaginal hysterectomy is for the authors the best way to perform hysterectomy, but unfortunately it is not always possible in benign lesions and may be insufficient for malignant tumors. As from 1992, they have introduced laparoscopy in their therapeutical approach. From January 1992 to February 1995 they have performed 268 hysterectomies and in 34 cases have done a laparoscopically prepared intervention. They precise their indications, surgical techniques, analyze their results and compare their experience to that found in the literature.

Female↗