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Biomedical subjects

D Shapiro

Publications and source records attributed to D Shapiro.

At least 91 records · Page 5Linked to original sources
PubMed1991

Bkm satellite DNA and ZFY in the coral reef fish Anthias squamipinnis.

We studied DNA from the protogynous sex-changing fish Anthias squamipinnis to evaluate the recent observation that male-specific bands are identified after hybridization with Bkm, a probe originating in the W chromosome of the snake Bungarus fasciatus. Sex-specific hybridization would imply modification of DNA structure during the sex-changing process. No sex-specific Bkm fragments were identified in our study, after digestion of DNA from 15 males and 11 adult females, despite the use of 12 different restriction enzymes. However, hybridization with Bkm did produce a distinct fingerprint pattern, similar to the fingerprint patterns described for other species after hybridization with GATA (GACA) type probes. In other experiments, the pDP1007 probe, which identifies the ZFY gene in the male-determining region of the human Y chromosome, generated identical hybridization patterns in DNA from males and females of A. squamipinnis and estimation of DNA mass by flow cytometry revealed identical genome sizes.

Animals↗
PubMed1990

The beat-to-beat blood pressure response to postural change in young and elderly healthy adult males.

Heart rate and blood pressure were studied with the beat-to-beat tracking cuff system in two groups (n = 20 per group) of healthy, unmedicated males, one between 60 and 75 years of age and the second between 18 and 29 years of age. The study confirms the previously reported blunted heart rate response to standing and the fact that, when blood pressure is recorded by conventional means, the response exhibited during orthostasis does not differ in healthy groups of young and elderly subjects. With the tracking cuff system, however, the elderly exhibited a smaller immediate systolic and diastolic drop in response to the change to upright posture and less variability in beat-to-beat blood pressure changes. The results have implications for cardiovascular studies, where age and posture can influence both blood pressure and heart rate.

Adolescent↗
PubMed1990

Cardiovascular response during postural change in the elderly.

In order to evaluate the heart rate and blood pressure response during sitting and standing, as well as during the change from sitting to standing, we studied 40 healthy men and women, aged 60-76 years, by means of a noninvasive beat-to-beat blood pressure tracking cuff. Heart rate and blood pressure curves immediately after standing exhibited pronounced flattening relative to a younger population, with no differences between men and women. Only four subjects showed systolic blood pressure drops of at least 15 mmHg in response to standing. Both handgrip and mental arithmetic significantly modified the cardiovascular response from sitting to standing, raising the possibility that individuals with orthostatic hypotension and impaired circulatory reflexes could be trained to utilize behavioral techniques as a means of preventing blood pressure from dropping too far during orthostasis.

Aged↗
PubMed1989

A two-site immunoradiometric assay for C-reactive protein in serum.

An immunoradiometric assay was developed for C-reactive protein in serum. The assay had a sensitivity of 5 micrograms/l and good precision. Correlation with radial immunodiffusion (r = 0.916) and EMIT (r = 0.935) was close. A reference range for healthy adults of 0.05-4.0 mg/l was derived.

C-Reactive Protein↗
PubMed1989

Management and prognosis of head and neck sarcomas.

Between 1962 and 1988, a total of 104 patients with head and neck rhabdomyosarcoma (RMS) and 17 patients with nonrhabdomyosarcoma (NRMS) were evaluated and treated at St. Jude Children's Research Hospital. All parameningeal sites (middle ear, orbit, or nasopharynx) were excluded from further analysis; thus, 50 patients represent the cohort of head and neck sarcomas for this review. Survival was good in this group of patients, 28 of 50 being alive and disease-free at last follow-up. Twenty of the 38 patients with RMS were alive and disease-free. Similarly, 8 of the 12 patients with NRMS were disease-free at a median follow-up of 5 years. However, the site and size of the primary tumor impacted on the extent of the initial resection and further treatment in addition to surgery. Although the treatment policy evolved over time to a stage-specific strategy for treatment modalities, the data suggest that surgery alone may be sufficient initial therapy for a subset of patients. For patients in whom complete resection is not achieved, the addition of radiotherapy and chemotherapy may result in improved survival.

Adolescent↗
PubMed1989

Impact of caffeine and psychological stress on blood pressure in black and white men.

The purpose of this study was to examine the effects of caffeine and psychological stress on systolic blood pressure (SBP) and heart rate (HR) in 40 healthy Black and White male regular coffee drinkers. Half the subjects had a positive family history of hypertension (FH+), and half did not. The effects of 250 mg of caffeine versus placebo (3 mg) in decaffeinated coffee were compared in a within-subject, double-blind, cross-over design. SBP and HR were measured at rest, after caffeine ingestion, during mental arithmetic stress, and during recovery. Results confirmed previous findings with White men that a moderate dose of caffeine produced significant increases in SBP and little effect on HR and that the pressor effects of caffeine and stress combined additively. Contrary to expectations, no overall race or family history differences in SBP levels or in SBP reactivity were observed. FH+ Blacks, however, evidenced slower SBP recovery than Whites. Whites evidenced higher overall HR levels than blacks, but this difference was not specific to caffeine or to mental stress. Mechanisms of racial differences in reactivity underlying differential risk for hypertension are discussed, as well as the utility of caffeine as a pharmacologic probe for such differences.

Adolescent↗
PubMed1989

Acute phase reaction during chemotherapy in small cell lung cancer.

We have measured the serum concentration of the acute phase reactant, C-reactive protein (CRP), in 20 patients with histologically proven small cell lung cancer undergoing their first pulse of induction cytotoxic chemotherapy. Baseline CRP concentrations were raised in 16 of 20 patients (median baseline CRP 18.5 mg l-1; normal range less than 10 mg l-1). CRP levels more than doubled in 11 of 20 patients during induction chemotherapy. This acute phase reaction was seen in seven of the 10 chemosensitive patients, but was not observed in any of the five non-responding patients. Five patients were non-evaluable for chemoresponse. These data indicate that there is a previously undescribed quantifiable acute phase response during chemotherapy for small cell lung cancer which has potential for predicting chemoresponse.

Acute-Phase Reaction↗
PubMed1989

Discrimination of mode of action of anxiolytics using an integrated computer data bank and Dynamic Brain Mapping (CNS effects of diazepam and lorazepam).

In a double-blind, placebo-controlled, crossover study, the CNS effects of intravenously administered diazepam and lorazepam were investigated in anxious subjects through the quantitative pharmaco-EEG (QPEEG) method. For up to 4 1/2 hours following administration the effects of each substance on brain function were measured using computer analyzed EEG recordings (CEEG) and a new technique called Dynamic Brain Mapping. The following observations were made: 1. Both active drugs produce statistically significant CNS effects as measured by CEEG changes. These changes were observed earlier with diazepam than with lorazepam. 2. Although both compounds are classified as anxiolytic by the routine computer EEG data base, the detailed brain mapping technology indicated that the CNS effects of diazepam and lorazepam were quantitatively and qualitatively different. 3. Clinical CNS side-effects (sedation) were seen more frequently with lorazepam than with diazepam. This was consistent with the EEG slowing producing properties of lorazepam. The EEG fast activity which is characteristic for all anxiolytics was established more with diazepam than lorazepam.

Adult↗
PubMed1989

The symptomatic lumbar spine in the athlete.

The lumbar spine is resistant to serious injury in normal athletic activity, but it can often be symptomatic. Although the symptoms are frequently musculotendinous in origin, it is important that structural causes be recognized early, particularly in the skeletally immature athlete. In the mature athlete, it is important to be aware of the normal aging process and the resultant structural changes that occur in the lumbar spine. Accurate assessment of this process is often necessary for sound management.

Aging↗
PubMed1988

Influence of whole body protein turnover rate on resting energy expenditure in patients with cancer.

Whole body protein turnover and resting energy expenditure are measured simultaneously in weight stable and weight losing patients with lung (n = 22) or colorectal cancer (n = 38). These results were compared with those from weight stable and weight losing non-cancer controls (n = 22). Rates of whole body protein turnover were calculated from the plateau isotopic enrichment of urinary ammonia and urea following a primed, continuous, 24-h infusion of [15N]glycine. Resting energy expenditure was measured by indirect calorimetry. All groups of cancer patients had significantly elevated rates of whole body protein turnover (P less than 0.05) and synthesized, on average, 1.9 g/kg/day more protein compared with weight stable non-cancer controls. In contrast, the resting energy expenditure of cancer patients and controls was similar. Moreover, there was no correlation between individual rates of whole body protein turnover. Thus, although cancer patients had rates of whole body protein turnover which were 50-70% greater than controls, this did not result in a measurable increase in resting energy expenditure. The assumption that elevation of whole body protein turnover or resting energy expenditure causes weight loss in cancer patients must be an oversimplification. An acute phase protein response was observed in the majority of cancer patients. Although the presence of such an inflammatory response did not correlate with the rate of whole body protein turnover, the role of inflammatory mediators in the pathogenesis of disturbed protein metabolism in cancer patients merits further investigation.

Aged↗
PubMed1988

Rapid, sensitive detection of plasma IL-1 by extraction and bioassay.

A method for separating IL-1 from plasma inhibitors by silica extraction has been developed and coupled to a highly sensitive bioassay using the LBRM TG6 cell line and the I1-2 dependent HT2A cell line. Using this assay we have detected IL-1 activity in plasma from patients undergoing elective surgery.

Animals↗
PubMed1988

Psychophysiological reactivity to mental arithmetic stress in black and white normotensive men.

Racial differences in physiological responses to a behavioral stressor were examined. Thirty-four Black and 42 White male normotensives 34 to 55 years old (mean age = 43.01 years) performed a mental arithmetic task while blood pressure, heart rate, and skin conductance were recorded. Compared to Whites, Blacks had significantly higher baseline diastolic blood pressure (77.93 mm Hg vs. 73.11 mm Hg) and lower skin conductance levels (11.08 microS vs. 12.25 microS). These effects persisted during performance of the mental arithmetic task. However, when baseline differences were covaried, there were no significant physiological effects associated with the task. Analysis of changes in response levels from baseline revealed a nonsignificant trend for Whites to show greater increases in systolic blood pressure than Blacks. There were no significant race or family history effects. Further, task performance did not influence the outcome. Failure to demonstrate greater cardiovascular reactivity in Blacks and all men with a positive family history of hypertension is discussed with regard to possible "survivor effects" and methodologic limitations.

Adult↗
PubMed1988

Mental and physical stress as moderators of the postural response in insulin-dependent diabetic patients.

Two simple stressors, mental arithmetic and isometric handgrip, were studied as moderators of the physiological response to standing in insulin-dependent diabetic patients and in healthy controls. Continuous (beat-to-beat) measures were taken of heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and skin conductance (SC) during postural change under baseline and stressor conditions. Diabetic patients without symptoms of neuropathy and healthy controls showed generally similar responses to postural change and to the stressor conditions. SBP and DBP were more responsive to the mental and physical stressors than were HR or SC, especially after standing. Two diabetic patients with postural hypotension showed significant increases in overall BP levels and less of a fall in BP during postural change under the stressor conditions, despite minimal HR or SC responses. Results indicate that these strategies are effective in increasing BP during postural change in both diabetic and nondiabetic individuals and may be useful in the management of orthostatic hypotension.

Adult↗