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Biomedical subjects

R Marcus

Publications and source records attributed to R Marcus.

At least 127 records · Page 7Linked to original sources
PubMed1995

Occupational blood contact among prehospital providers.

STUDY OBJECTIVE: To assess the nature and frequency of blood contact (BC) among emergency medical service (EMS) workers. DESIGN: During an 8-month period, we interviewed EMS workers returning from emergency transport calls on a sample of shifts. We simultaneously conducted an HIV seroprevalence survey among EMS-transported patients at receiving hospitals served by these workers. SETTING: Three US cities with high AIDS incidence. PARTICIPANTS: EMS workers. RESULTS: During 165 shifts, 2,472 patients were attended. Sixty-two BCs (1 needlestick and 61 skin contacts) were reported. Individual EMS workers had a mean of 1.25 BCs, including .02 percutaneous exposures, per 100 patients attended. The estimated annual frequency of BC for an EMS worker at the study sites was 12.3, including .2 percutaneous exposures. For 93.5% of the BCs, the HIV serostatus of the source patients was unknown to the EMS worker. HIV seroprevalences among EMS-transported patients at the three receiving hospital emergency departments were 8.3, 7.7, and 4.1 per 100 patients; the highest rates were among male patients 15 to 44 years old who presented with pneumonia. CONCLUSION: EMS personnel regularly experience BCs, most of which are skin contacts. Because the HIV serostatus of the patient is usually unknown, EMS workers should practice universal precautions. Postexposure management should include a mechanism for voluntary HIV counseling and testing of the patient after transport and transmittal of the results to the EMS.

Adolescent↗
PubMed1995

A pilot study of oral glutamine supplementation in patients receiving bone marrow transplants.

Data from animal studies suggests that glutamine supplementation may reduce the incidence or severity of cytotoxic-induced mucositis. This study examined the effect of glutamine supplements on mucositis in patients receiving bone marrow transplants. 24 patients were randomly assigned to receive an oral supplement of either glutamine or placebo (16 g/day) from the time of transplantation until discharge from hospital. There was no significant difference in the incidence of oral mucositis, assessed either by the patient (mucositis score: glutamine 17 vs. placebo 26.6) or an independent observer (glutamine 31.1 vs. placebo 32.3), or the number of days of diarrhoea (glutamine 3.1 vs. placebo 3.3 days). Similarly there were no significant differences in haematological indices (haemoglobin, WBC, platelets), the requirement for parenteral nutrition or hospital stay. Possible reasons for this negative result, which contrasts with those obtained in recent studies of patients receiving intravenous glutamine after bone marrow transplants, are discussed.

Journal Article↗
PubMed1995

Skin and mucous membrane contacts with blood during surgical procedures: risk and prevention.

OBJECTIVE: To study the epidemiology and preventability of blood contact with skin and mucous membranes during surgical procedures. DESIGN: Observers present at 1,382 surgical procedures recorded information about the procedure, the personnel present, and the contacts that occurred. SETTING: Four US teaching hospitals during 1990. PARTICIPANTS: Operating room personnel in five surgical specialties. MAIN OUTCOME MEASURES: Numbers and circumstances of contact between the patient's blood (or other infective fluids) and surgical personnel's mucous membranes (mucous membrane contacts) or skin (skin contacts, excluding percutaneous injuries). RESULTS: A total of 1,069 skin (including 620 hand, 258 body, and 172 face) and 32 mucous membrane (all affecting eyes) contacts were observed. Surgeons sustained most contacts (19% had > or = 1 skin contact and 0.5% had > or = 1 mucous membrane-eye contact). Hand contacts were 72% lower among surgeons who double gloved, and face contacts were prevented reliably by face shields. Mucous membrane-eye contacts were significantly less frequent in surgeons wearing eyeglasses and were absent in surgeons wearing goggles or face shields. Among surgeons, risk factors for skin contact depended on the area of contact: hand contacts were associated most closely with procedure duration (adjusted odds ratio [OR], 9.4; > or = 4 versus < 1 hour); body contacts (arms, legs, and torso) with estimated blood losses (adjusted OR, 8.4; > or = 1,000 versus < 100 mL); and face contacts, with orthopedic service (adjusted OR, 7.5 compared with general surgery). CONCLUSION: Skin and mucous membrane contacts are preventable by appropriate barrier precautions, yet occur commonly during surgery. Surgeons who perform procedures similar to those included in this study should strongly consider double gloving, changing gloves routinely during surgery, or both.

Adult↗
PubMed1995

Maximal muscle strength of elderly women is not influenced by oestrogen status.

It has recently been reported that oestrogen replacement may preserve the ratio of muscle strength to cross-sectional area in the hand in addition to its beneficial effect on bone mass in postmenopausal women. Since muscle strength is associated with falls and fractures in elderly people, this additional effect of oestrogen replacement could be of considerable benefit to postmenopausal women. We therefore wished to determine whether this effect was also evident in larger muscle groups that are involved in ambulation, balance, and activities of daily living. We examined the relationship of oestrogen replacement therapy (ORT) to maximal dynamic muscle strength in 85 healthy women aged 65-82 years. Thirty-seven women were currently taking ORT and had been on stable doses for 2 to 43 years [17.8 (1.8); mean (SEM)], while 48 women had no previous exposure to postmenopausal oestrogen therapy. Dynamic muscle strength was determined for five standard lower-body exercises using isotonic equipment by the 1-RM method. Bone mineral density (BMD, g/cm2) of the axial and appendicular skeleton as well as body composition was assessed by dual-energy X-ray absorptiometry. There was no difference between subjects according to ORT status for age, height, weight, lean body mass (LBM), fat mass, or percentage body fat. BMD of the spine (L2-4), mid-radius, and whole body was greater (p < 0.001) in individuals receiving ORT, with no significant difference at the femoral neck. No differences existed between groups for lower-body muscle strength. Normalizing muscle strength to body mass and LBM did not alter the result.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Relationship of age-related decreases in muscle mass and strength to skeletal status.

In this presentation, age-related bone loss is seen to be the consequence of a small yet persistent insufficiency in bone remodeling, where small deficits in bone mass remain upon completion of each remodeling cycle. Although loss of bone and of muscle strength develop together over time, remodeling imbalance appears to emerge much earlier than does loss of muscle mass and strength. Thus, age-related bone loss cannot be ascribed entirely to the loss of muscle. Although muscular action does influence bone mass, its most impressive effects occur between complete immobilization and ambulatory, but sedentary life. Regardless of the minor role sarcopenia may play in bone loss, muscle weakness exerts a powerful influence on hip fracture incidence because of its effect on the risk of falls.

Accidental Falls↗
PubMed1995

A physician survey of therapy for exercise-associated amenorrhea: a brief report.

Amenorrheic athletes face an increased risk of osteopenia and stress fractures. Optimal treatment for exercise-associated amenorrhea remains controversial, reflecting limited data on the therapeutic effects of hormonal or nutritional intervention in the prevention of osteopenia. To determine physician opinions regarding preferred management of amenorrheic athletes, members of the American Medical Society for Sports Medicine (AMSSM) were surveyed by questionnaire. Practitioners were asked if they prescribed sex steroid replacement, calcium supplementation, weight gain, or decreased physical activity for amenorrheic athletes. The 159 respondents included predominantly sports medicine (56%) and family medicine (32%) physicians. Sex steroid replacement was endorsed by 92%, calcium supplementation by 87%, increased caloric intake by 64%, decreased exercise intensity by 57%, weight gain by 43%, and vitamin supplementation by 26%. These findings suggest that sex steroids are used commonly to treat amenorrheic athletes, despite the paucity of data demonstrating their efficacy in preserving bone mass in this disorder. Further research is needed to define the benefits of estrogen alone or in combination with nutritional intervention for preserving bone mass in female athletes.

Adolescent↗
PubMed1995

Erythrodermic mycosis fungoides treated with total body irradiation and autologous bone marrow transplantation.

We describe a middle-aged man with aggressive erythrodermic mycosis fungoides whose responses to several well-established therapies for the disease were either poor or short-lived. Infusion of antibodies engineered against cells expressing the CD4 molecule produced little response. Total body irradiation coupled with autologous bone marrow transplantation led to an encouraging but unfortunately unsustained improvement.

Adult↗
PubMed1995

Heterologous mesenchymal proliferation of the skin.

BACKGROUND: A benign cutaneous mesenchymal lesion with features of dermatofibroma, dermatomyofibroma, and lipoma is described. OBJECTIVE: An attempt is made to classify this previously undescribed entity. METHODS: Tissue sections were studied with routine hematoxylin and eosin and a battery of immunoreactants to ascertain the nature of the cells within the lesion. RESULTS: The lesion described has a unique histologic appearance, containing elements of mature adipose tissue, smooth muscle, and fibrous tissue. CONCLUSION: Our findings suggest that this tumor is a distinct entity that is not exactly like any previously described lesion and we have given it a descriptive name.

Adult↗
PubMed1995

Effect of sustained resistance training on basal metabolic rate in older women.

OBJECTIVE: To determine if basal metabolic rate (BMR) could be elevated in older women undertaking a program of progressive resistance exercise of up to 52-weeks duration. DESIGN: Randomized controlled trial with subjects assigned to either a control (CO), high-intensity (HI), or low-intensity (LO) training group for 15 weeks. BMR, body composition, energy intake and expenditure, and muscle strength were assessed at baseline and after 15 weeks. Subjects were encouraged to continue in their assigned exercise group for an additional 37 weeks, after which time they were reevaluated. SETTING: An exercise facility at a medical center. SUBJECTS: Thirty-six community-dwelling healthy women aged 65 to 79 years. INTERVENTION: Exercise groups performed three sets of 10 exercises, 3 days/week, at either 80% of one-repetition maximum (1-RM) for seven repetitions (HI) or 40% of 1-RM for 14 repetitions (LO). MEASURES: BMR by indirect calorimetry, body composition by dual energy X-ray absorptiometry, energy intake and expenditure from 4-day dietary and activity records, and dynamic muscle strength by 1-RM. RESULTS: Muscle strength increased, on average (+/- SEM), by 40 +/- 6% and 36 +/- 7% in the HI and LO groups after 15 weeks, respectively, compared with 4 +/- 1% in the nonexercising subjects (P = .0001). Fat mass decreased after 15 weeks in LO exercisers by 1.0 kg (P < .05), whereas there was a trend for fat-free mass (FFM) to increase in the HI group by 0.7 kg (P = .08). No change occurred in any group for BMR. From weeks 15 to 52, muscle strength increased a further 9 +/- 2% and 11 +/- 2% in HI and LO groups, respectively, compared with 3 +/- 1% in nonexercisers (P < .005). There was no change in BMR or any body composition parameter during this time period. CONCLUSIONS: Neither training program significantly altered BMR and both produced only minimal changes in body composition. However, both the HI and LO exercise regimens resulted in similar and substantial gains in upper and lower body muscle strength that persisted over the course of the year. This suggests that either exercise regimen may prove an effective strategy for preventing frailty and maintaining functional independence in older adults.

Aged↗
PubMed1995

The effects of recombinant human insulin-like growth factor-I and growth hormone on body composition in elderly women.

The purpose of this study was to determine the effects of recombinant human GH (rhGH; 0.025 mg/kg.day) and one of two doses of recombinant human insulin-like growth factor-I (rhIGF-I; 0.015 and 0.060 mg/kg, twice daily) on body composition in elderly women. Sixteen healthy elderly women (mean age +/- SEM, 71.9 +/- 1.3 yr) were randomly assigned to receive either rhGH (GH; n = 5), low dose rhIGF-I (n = 6), or high dose rhIGF-I (n = 5). A 2-week predrug baseline period was followed by 4 weeks of hormone treatment, with a standardized diet fed throughout. All groups experienced a significant increase in serum IGF-I and IGFBP-3 levels over the treatment period, accompanied by significant decreases in IGF-II (P < 0.05). Fat mass decreased in all groups, with significant increases in lean body mass and nitrogen retention occurring in the high dose IGF and GH groups. Total body water did not change, whereas increases observed in intracellular fluid approached significance (P = 0.06). These anabolic changes were accompanied by numerous negative side-effects in the GH and high dose IGF groups, including headaches, lethargy, joint swelling/pain, and bloatedness. The low IGF dose was well tolerated. These results demonstrate that the administration of rhGH and rhIGF-I for 4 weeks results in anabolic changes in body composition in elderly women.

Aged↗
PubMed1995

Percutaneous exposures to HIV-infected blood. Among dental workers enrolled in the CDC Needlestick Study.

The authors found that 19 percutaneous exposures among dental workers occurred both during and after use of instruments such as syringe needles and scalers. Specific information about the device and action associated with an exposure is important for prevention efforts, including safer instruments and work practices. Most of these exposures probably involved smaller, rather than larger, amounts of blood infected with the human immunodeficiency virus. To our knowledge, none of the exposures resulted in HIV transmission to an enrolled dental worker.

Accidents, Occupational↗
PubMed1995

Dynamic muscle strength as a predictor of bone mineral density in elderly women.

Although muscle strength has been shown to predict bone mineral density (BMD) in older adults, the variance explained by isometric and isokinetic testing has been generally low (< 20%) and limited to only a few exercises and muscle groups. To elucidate the relationship of muscle strength to BMD at multiple sites, and to ascertain the most robust predictor of BMD using isotonic strength testing apparatus, we examined dynamic muscle strength and BMD in 40 healthy elderly women aged 65-82 years. BMD of the spine (L2-4), proximal femur (neck, trochanter, Ward's triangle), forearm (midradius), and whole body were measured by dual-energy X-ray absorptiometry. Dynamic strength (1-RM), utilizing isotonic weight-lifting equipment, was assessed for 10 standard upper and lower body exercises. In stepwise multiple regressions, leg press was the only independent predictor of spine (R2 = 0.11), neck and trochanter (R2 = 0.21 and 0.18), forearm (R2 = 0.21), and whole body BMD (R2 = 0.19), while bench press was an independent predictor of Ward's BMD (R2 = 0.12). The most robust predictor of regional and whole body BMD using isotonic equipment was the leg press, which may reflect overall skeletal health in this population. The portion of variance explained by dynamic muscle strength (11-21%) is similar to that reported when strength is assessed by isometric and isokinetic testing. The relationship of dynamic strength to BMD was not generally site-specific.

Absorptiometry, Photon↗
PubMed1995

Calcium disorders of pregnancy.

This article begins with a discussion on changes in the maternal calcium-parathyroid axis in response to pregnancy, followed by calcium disorders that can take place during pregnancy. Hypercalcemia and its subsequent disorders, including hyperparathyroidism, hypocalciuric hypercalcemia, and thyroid disease, are reviewed. Also, hypocalcemia and its subsequent disorders, including hypoparathyroidism, vitamin D deficiency, and hypomagnesemia, are addressed. Concluding the article are discussions on bone status and osteoporosis, calcium metabolism in pregnancy-induced hypertension and preeclampsia, and nephrolithiasis in pregnancy.

Adult↗
PubMed1994

Does estimating volumetric bone density of the femoral neck improve the prediction of hip fracture? A prospective study. Study of Osteoporotic Fractures Research Group.

Standard projectional bone density of the femoral neck (BMD), defined as bone mineral content divided by the projected area of the neck, predicts hip fractures but may not accurately estimate the true volumetric bone density of the femoral neck. To determine whether an estimate of the volumetric bone density of the neck, "bone mineral apparent density" (BMAD), would be a better predictor of hip fracture, we analyzed dual x-ray absorptiometry scans obtained prospectively from 7963 older white women, of whom 83 suffered a hip fracture during follow-up. Both BMD and BMAD were stronger predictors than bone mineral content (BMC) of the femoral neck. However, BMD and BMAD had very similar predictive values for hip fracture: each standard deviation decrease in either BMD or BMAD of the femoral neck increased the age-adjusted risk of hip fracture 2.6- to 2.7-fold. We conclude that BMD and BMAD of the femoral neck have a similarly strong predictive value for hip fracture.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗
PubMed1994

Correlates of bone mineral density in the postmenopausal estrogen/progestin interventions trial.

We assessed the cross-sectional relationship of age, menopausal years, body mass, previous estrogen use, and ethnic background to bone mineral status in a sample of 875 healthy postmenopausal women at the time they were recruited from the community to participate in a multicenter clinical trial. The women were 1-10 years postmenopause, 45-64 years of age, and had not received estrogen replacement therapy within 3 months of enrollment. Of the participants, 89% were white, 69% had a spontaneous menopause, and 53% had a history of previous estrogen replacement therapy. Bone mineral density (BMD) of the lumbar spine (L2-4) and proximal femur was measured by dual-energy x-ray absorptiometry. Results were consistent with a significant negative linear regression of BMD on age or years from menopause. Body mass index (BMI) correlated significantly with BMD at all sites (L 2-4 r = 0.28; femoral neck r = 0.34, p < 0.0001). BMD adjusted for age and BMI were higher at both sites in women who had taken estrogen versus those who had not (L2-4 0.976 +/- 0.009 versus 0.932 +/- 0.01; femoral neck 0.740 +/- 0.006 versus 0.708 +/- 0.008, p < 0.05). Adjusted BMD also increased with duration of ERT. Parity was negatively associated with L2-4 BMD (p = 0.03) but did not correlate significantly with BMD at the femoral neck. Black women had the highest L2-4 BMD, and Hispanic women had the highest femoral neck BMD, even when results were adjusted for age and BMI. When data were corrected for differences in bone size, these interethnic differences were no longer significant. We conclude that increased body mass is positively correlated with BMD, and this may confer a degree of skeletal protection to heavier postmenopausal women. Exposure for 5 years to exogenous estrogen is associated with significantly increased age- and BMI-adjusted BMD.

Absorptiometry, Photon↗