Search PubMed⌕ Search

Biomedical subjects

S Maloney

Publications and source records attributed to S Maloney.

11 recordsLinked to original sources
PubMed1994

Autogenic-feedback training: a potential treatment for orthostatic intolerance in aerospace crews.

Postflight orthostatic intolerance has been identified as a serious biomedical problem associated with long-duration exposure to microgravity in space. High priority has been given to the development of countermeasures for this disorder that are both effective and practical. A considerable body of clinical research has demonstrated that people can be taught to increase their own blood pressure voluntarily, and that this is an effective treatment for chronic orthostatic intolerance in paralyzed patients. The current pilot study was designed to examine the feasibility of adding training in control of blood pressure to an existing preflight training program designed to facilitate astronaut adaptation to microgravity. Using an operant conditioning procedure, autogenic-feedback training (AFT), three men and two women participated in four to nine training (15-30-minute) sessions. At the end of training, the average increase in systolic and diastolic pressure, as well as mean arterial pressures, that the subjects made ranged between 20 and 50 mm Hg under both supine and 45 degrees head-up tilt conditions. These findings indicate that AFT may be a useful alternative treatment or supplement to existing approaches for preventing postflight orthostatic intolerance. Furthermore, the use of operant conditioning methods for training cardiovascular responses may contribute to the general understanding of the mechanisms of orthostatic intolerance.

Adult↗
PubMed1994

Mycobacterium abscessus pseudoinfection traced to an automated endoscope washer: utility of epidemiologic and laboratory investigation.

After 15 patients had positive cultures for Mycobacterium abscessus without evidence of infection (i.e., pseudoinfection) following endoscopy, retrospective cohort studies of patients undergoing endoscopy and microbiologic sampling of the environment were done to examine potential nosocomial transmission and to identify the source and risk factors for M. abscessus pseudoinfection. In the epidemic period, M. abscessus-positive cultures were significantly more likely to be obtained during bronchoscopy than gastroendoscopy (16/149 vs. 1/860, P < .001) and during procedures using bronchoscopes disinfected in an automated washer rather than by other methods (16/54 vs. 0/95, P < .001). M. abscessus was recovered from the automated washer, the inlet water feeding the washer, and a flexible bronchoscope. Environmental and case-patient isolates had identical large restriction fragment (LRF) patterns of genomic DNA separated by pulsed-field gel electrophoresis. Molecular typing using LRF analysis supported the epidemiologic results and demonstrate the utility of combined epidemiologic and laboratory investigations in nosocomial outbreaks of nontuberculous mycobacteria.

Adult↗
PubMed1993

DNA large restriction fragment patterns of sporadic and epidemic nosocomial strains of Mycobacterium chelonae and Mycobacterium abscessus.

Large restriction fragment (LRF) pattern analysis of genomic DNA using pulsed-field gel electrophoresis was performed on three reference strains, 32 sporadic isolates, and 92 nosocomial isolates from 12 epidemics of Mycobacterium chelonae and Mycobacterium abscessus. Only 17 of 30 (57%) unrelated strains of M. abscessus, compared with 10 of 11 (91%) of M. chelonae strains, gave satisfactory DNA extractions, with the remainder resulting in highly fragmented DNA. DraI, AsnI, XbaI, and SpeI gave satisfactory LRF patterns. Sporadic isolates of the two species had highly variable LRF patterns, except for one reference strain and one sporadic isolate of M. chelonae that differed by only two to five bands. Evaluation of repeat isolates from five patients monitored for 8 months to 13 years (mean, 5.8 years) revealed LRF patterns to be stable, with changes of not more than two bands. LRF analysis of the seven nosocomial outbreaks with evaluable DNA revealed identical patterns in most or all of the patient isolates and in three outbreaks revealed identity with environmental isolates. These outbreaks included endoscope contamination, postinjection abscesses, and surgical wound infections. LRF analysis of genomic DNA is a useful technique for epidemiologic studies of M. abscessus and M. chelonae, although improved technology is needed for the approximately 50% of strains of M. abscessus with unsatisfactory DNA extractions.

Cross Infection↗
PubMed1992

Incorporation of sodium fluoride into cortical bone does not impair the mechanical properties of the appendicular skeleton in rats.

Clinical studies on the use of sodium fluoride (NaF) in osteoporotic patients have demonstrated increased spinal bone mass without a reduction in vertebral fracture incidence, and a trend towards reduced appendicular bone mass with an increase in peripheral fracture incidence. As previous reports have suggested that NaF becomes incorporated into bone's crystal structure, possibly affecting bone strength, we sought to examine the relationship among bone fluoride content, bone mass, and skeletal fragility. Twenty-one-day-old female Sprague-Dawley rats were treated with four different doses of NaF. The tibiae were subjected to histomorphometric and biochemical analyses, and the femora were tested in torsion for the properties of strength, stiffness, energy storage capacity, and angular deformation. The results showed that over 50% of the skeleton in these rats was turned over in the presence of NaF. The four different doses resulted in a linear increase in bone F concentration and suggested excellent absorption and incorporation of this drug. No changes in histomorphometric indices of bone formation or turnover were found. Despite the large fraction of bone formed during NaF treatment, and the linear increase in bone fluoride content in relation to dose, there were no changes observed in any of the mechanical properties. These results suggest that, even extensive incorporation of fluoride into bone, in the absence of an effect on bone mass or remodeling, does not significantly alter its capacity to withstand mechanical loads.

Animals↗
PubMed1992

Perforation of the augmented bladder.

In 12 of 264 children treated with enterocystoplasty 15 spontaneous perforations occurred. Of the 12 children 9 had myelodysplasia. All segments of the gastrointestinal tract were used for the augmentation and most were detubularized. Surgery to increase bladder outlet resistance was done in 8 cases. At the time of each perforation 9 children had sterile cultures, however, 3 died of overwhelming sepsis. Presenting signs included abdominal pain in 8 cases, septic shock in 4 cases and shoulder pain in 4 older myelodysplastic children with diaphragmatic irritation from escaping urine. Cystography demonstrated a leak in 10 of 11 cases. Urodynamic studies revealed good compliance with low maximum filling pressure in 8 of 10 children. Hyperreflexia was noted in only 5 cases and outlet resistance greater than 85 cm. water was demonstrated in 5. Histological analysis showed changes in the bowel wall consistent with ischemia but suture granulomas were present in areas adjacent to the perforation site or thinned areas in biopsy or autopsy specimens. In addition to the theory that overdistention may cause enterocystoplasty perforation, current detubularization techniques may produce areas of relative ischemia, which become accentuated when the augmented bladder is distended beyond a reasonable volume.

Adolescent↗
PubMed1986

Work function analysis of vegetarian entrée production.

Data on labor time for food production can be used as an effective management tool. It is essential for foodservice managers to know how labor time is being used (1). A continuous time study was conducted to determine total labor time for the production of eight vegetarian entrées in a hospital foodservice system. Two work areas were observed: the ingredient assembly area and the cooks' production area. Times were recorded by work function to identify how labor time was distributed. Results showed (a) observed frequency for each work function, (b) time expended in seconds per portion for each work function, (c) percentage distribution of labor time by work function, (d) total time for each employee involved in entrée production, and (e) percentage of total time in which each employee was involved in the production of each entrée. Total labor time varied by type of entrée, ranging from 39.97 to 19.33 seconds per portion. Entrées with the highest labor time required the largest amount of hand labor. A one-way analysis of variance indicated significant differences in mean labor time among the eight vegetarian entrées for direct labor time (p = .0009), and total labor time (p = .0018). No significant differences were found among entrées for indirect labor or delay time.

Cooking↗