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S Lipson

Publications and source records attributed to S Lipson.

24 records · Page 2Linked to original sources
PubMed1988

Pathologic changes in the kidneys and other organs of dogs undergoing extracorporeal shock wave lithotripsy with a tubless lithotripter.

Extracorporeal shock wave lithotripsy (ESWL) is an accepted method of treatment for renal calculi. Complications are rare, although most patients experience temporary hematuria. Shock waves generated by a spark plug in a tubless lithotripter administered to stones placed into the renal pelves of dogs, resulted in interstitial renal hemorrhage developing acutely, and interstitial fibroblastic reactions chronically. The latter were linear, and were in the cortex and/or medulla. They resulted from organisation of the interstitial hemorrhages. In addition interstitial nephritis was present and this could be the result of the surgery, the stones, preexisting infection or the ESWL. Other organs were intact, with the exception of a hematoma in the large bowel of one dog. Lithotripsy, in this dog model, produced a spectrum of kidney injury.

Animals↗
PubMed1984

The effects of remodeling on the elastic properties of bone.

Cortical bone can be modeled as a complex hierarchical composite interrelating both structure and material properties on four levels of structural organization: molecular, ultrastructural, microscopic, and macroscopic. In young animals, the microstructural systems are long parallel lamellar units, plexiform bone, which in older or more mature animals converts by internal remodeling into multiple concentric lamellar units, secondary osteons, forming haversian bone. Ultrasonic wave propagation measurements performed on both plexiform and haversian bone clearly show a definitive relationship with microstructure; haversian bone can be described as a transversely symmetric material whereas plexiform bone appears to be orthotropic in nature. The anisotropy of the elastic constants are found to reflect the tissue symmetry; moreover, plexiform bone is stiffer and more rigid in all directions than is haversian bone. Similar experiments were performed on osteoporotic and osteopetrotic bone. While the results for osteoporotic bone are understandable in terms of the increased porosity, the results for the osteopetrotic bone are anomalous with respect to its density. Since Wolff, the remodeling of bone has been interpreted as a way of altering the mechanical properties to suit some need. For haversian remodeling from plexiform bone, the argument that adaptation occurs to optimize properties requires additional clarification since haversian bone appears to have inferior mechanical properties to plexiform bone.

Animals↗
PubMedDate not supplied

Withdrawal of haloperidol, thioridazine, and lorazepam in the nursing home: a controlled, double-blind study.

BACKGROUND: Ongoing regimens of haloperidol, thioridazine, and lorazepam are commonly administered to manage behavior problems in nursing home residents. Nevertheless, there is controversy over whether periodic drug withdrawal should be attempted when those medications are prescribed. This study addressed that issue by examining the effects of discontinuing treatment with haloperidol, thioridazine, and lorazepam among residents of a large suburban nursing home. METHODS: In a double-blind, crossover study, half of 58 nursing home residents (43 women and 15 men with a mean age of 86 years) continued to take the psychotropic medication they had been prescribed, whereas the other half were tapered to placebo. After 6 weeks of taking placebo or original drug, patients were tapered to the reverse schedule and remained on it for 6 weeks. Assessments included informant ratings by the nursing staff who completed the Brief Psychiatric Rating Scale and the Cohen-Mansfield Agitation Inventory. RESULTS: Analyses comparing residents taking placebo to those taking medication after completion of the first phase showed no impact of drug therapy discontinuation on their behavior. Similarly, using the crossover design to compare residents' behaviors while taking placebo vs. taking drugs, withdrawal of medication had no impact on Cohen-Mansfield Agitation Inventory or Brief Psychiatric Rating Scale scores. CONCLUSIONS: Results of this work suggest that longterm use of haloperidol, thioridazine, and lorazepam in nursing homes to manage agitation should be closely monitored for their efficacy. Furthermore, routine attempts at drug withdrawal should be considered for most residents taking psychotropic medication.

Affect↗
PubMedDate not supplied

Prospective study of pneumonia hospitalizations and mortality of U.S. older people: the role of chronic conditions, health behaviors, and nutritional status.

Mortality and hospitalization rates for pneumonia have increased among older Americans during recent years (1979-86), despite a national commitment to the reduction of premature deaths from pneumonia. A prospective study of deaths and hospitalizations attributable to pneumonia was conducted among 5,474 subjects ages 55 and older who participated in the NHANES I Epidemiologic Followup Study. Prevalent chronic conditions, health behaviors, and nutritional status indicators, measured at baseline, were examined in relation to pneumonia hospitalization and death during 12 years of followup. Mortality and hospitalization rates for pneumonia were higher among men than women, and higher among those ages 65 and older than among those 55-64 of both sexes. Risk of pneumonia death was higher among subjects with a history of congestive heart failure, stroke, cancer, or diabetes. Risk of pneumonia hospitalization was higher among subjects with a history of chronic obstructive pulmonary disease and among men who were current smokers. Daily alcohol consumption did not increase risk of pneumonia in this study population. Four measures of nutritional status were examined taking age, prevalent chronic conditions, and cigarette smoking into account: body mass index, arm muscle area, and serum albumin and hemoglobin levels. Risk of pneumonia death was 2.6 times higher in men in the lowest quartile, compared with men in the highest quartile, of body mass index. Similarly, the risk was 4.5 times higher among men in the lowest quartile of arm muscle area. Risk of death from pneumonia was 3.6 times higher among women in the lowest quartile of serum albumin levels compared with women in the highest quartile. Relative risks for these nutritional status indicators remained elevated after adjusting for age and the medical history risk factors. These risk factors should be taken into account when designing and evaluating pneumonia vaccination trials and community prevention programs.

Adult↗