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S J Mann

Publications and source records attributed to S J Mann.

At least 37 records · Page 2Linked to original sources
PubMed1995

Isolated elevation of diastolic blood pressure. Real or artifactual?

Not infrequently, blood pressure measurement by the standard auscultatory technique yields a normal systolic pressure with an elevated diastolic pressure. The relatively narrow pulse pressure of such a measurement raises concern about the accuracy of the blood pressure measurement. The purpose of this study was to assess the accuracy of auscultatory blood pressure measurements in patients with an uncommonly narrow pulse pressure, particularly patients with an elevated diastolic but normal systolic pressure. Auscultatory blood pressure measurements were compared with an objective noninvasive standard, called K2 analysis, which has been shown to be more accurate than the auscultatory technique. Blood pressure was measured simultaneously by auscultatory and K2 techniques in 175 subjects. Comparisons were performed (1) in the group as a whole, (2) in four clinical subgroups (normotensive [< 140/< 90 mm Hg, n = 69], hypertensive [> or = 140/> or = 90 mm Hg, n = 53], isolated systolic hypertensive [> or = 140/< 90 mm Hg, n = 38], and isolated diastolic hypertensive [< 140/> or = 90 mm Hg, n = 15]), and (3) in two subgroups whose ratio of pulse pressure to diastolic pressure was greater than or equal to 0.45 (n = 151) or less than 0.45 (n = 24). Subjects in the isolated diastolic hypertensive group and in the group with a pulse pressure ratio less than 0.45 were considered to have a narrow pulse pressure. In the group as a whole, consistent with previous auscultatory-K2 comparisons, systolic pressure was slightly higher and diastolic pressure slightly lower when measured by K2 versus the auscultatory technique (auscultatory, 145/85 mm Hg; K2, 147/83 mm Hg).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Response to the captopril test is dependent on baseline renin profile.

OBJECTIVE: To determine prospectively the relationship between the renin-sodium profile and the renin response to captopril challenge in patients with essential hypertension. DESIGN: A standard captopril test was performed in 108 uncomplicated, untreated hypertensive subjects with normal renal function and urinary sodium excretion in the range 50-240 mmol/day. The subjects were selected from a working population with a low expected prevalence of renovascular disease. METHOD: The captopril test was considered positive if the captopril-induced rise in plasma renin activity met all three criteria established by Müller et al. Patients with a positive test and those meeting only one or two of the three criteria were further investigated for renovascular hypertension by measuring renal venous renins and by digital subtraction intravenous angiography. Renin responses were analyzed according to baseline renin-sodium profile. RESULTS: Nine of 108 subjects had a false-positive captopril test result. Among the subjects with a low or normal renin-sodium profile, 1% (one of 82) had a false-positive result. In contrast, false-positive results were seen in 31% (eight of 26) of high-renin subjects. False-positive test results were not related to urinary sodium excretion or to excessive decrease in blood pressure. The magnitude of the renin response to captopril was strongly and directly related to the baseline plasma renin activity. CONCLUSION: An exaggerated renin response to captopril challenge is common in patients with high-renin essential hypertension. Therefore, in a population with a low probability of renovascular hypertension, caution is recommended in interpreting a positive test result in patients with a high baseline renin.

Adult↗
PubMed1992

Detection of renovascular hypertension. State of the art: 1992.

PURPOSE: To review recent advances in detecting renovascular hypertension. DATA SOURCES: Original English-language reports obtained through a MEDLINE search for the years 1987 to 1991. Also, a manual search through Index Medicus as well as bibliographies of original reports and selected review articles. STUDY SELECTION AND DATA EXTRACTION: Cited studies were critically reviewed with emphasis on study size, patient sample, methods, diagnostic criteria, and reproducibility of results. Where applicable, reviews that combined the results of smaller studies are cited. RESULTS: A sensitivity of 74% and a specificity of 89% have been reported for the captopril test and of 93% and 95%, respectively, for captopril scintigraphy with diethylenetriaminepentaacetic acid (DTPA). The sensitivity and specificity of renal vein renin determination are 80% and 62%, respectively and may increase with the use of stricter technical criteria and maneuvers to stimulate renin secretion. These tests differentiate renovascular hypertension from essential hypertension more reliably than from asymmetric renal parenchymal disease; however, they do not reliably distinguish unilateral from bilateral stenosis. Other tests are less widely used. Intravenous pyelography (sensitivity, 74.5%; specificity, 86.2%) has the disadvantages of radiation and dye load exposure. Intravenous angiography is expensive and invasive and does not always enable visualization of the origin of the renal artery. The roles of duplex ultrasound and magnetic resonance angiography remain to be clarified. CONCLUSIONS: Noninvasive tests are cost effective and have a high predictive value in patients with clinical clues suggestive of renovascular hypertension. These tests are not recommended for use in patients with a low likelihood of disease.

Decision Trees↗
PubMed1992

Systolic hypertension in the elderly. Pathophysiology and management.

Isolated systolic hypertension occurs with increased prevalence in the elderly population. It is characterized by reduced vascular compliance, often combined with increased peripheral resistance. These changes are not specific to patients with systolic hypertension, occurring, perhaps to a lesser extent, in the normotensive aging population as well. Systolic hypertension is associated with a risk of cardiovascular morbidity and mortality that possibly exceeds that associated with systolic-diastolic hypertension. However, until the recent report of the Systolic Hypertension in the Elderly Program, the benefit of treatment of this population was undocumented. The Systolic Hypertension in the Elderly Program demonstrated that lowering of blood pressure with a diuretic, combined, when necessary, with a beta blocker, reduced the rate of myocardial infarction and stroke. Other agents may also be effective in lowering blood pressure, although their ability to reduce cardiovascular morbidity and mortality in this population remains to be documented. The results suggest that pharmacologic treatment be considered for patients older than 60 years whose systolic blood pressure remains above 160 mm Hg (with a diastolic pressure below 90 mm Hg). Whether treatment should be recommended for all patients with systolic hypertension, or, alternatively, for only those at higher risk for cardiovascular events, remains controversial.

Adrenergic beta-Antagonists↗
PubMed1991

Elevation of ambulatory systolic blood pressure in hypertensive smokers. A case-control study.

Although smoking raises blood pressure, the office blood pressure measurements of smokers are the same as, or lower than, those of nonsmokers. To resolve this paradox, we compared the office and 24-hour ambulatory blood pressures of 59 untreated hypertensive smokers with 118 nonsmoking hypertensives matched for age, sex, and race. The office blood pressures of the smoking and nonsmoking groups were 141/93 and 142/93 mm Hg, respectively. The awake ambulatory systolic blood pressure was significantly higher in the smokers (145 vs 140 mm Hg). This difference was greater among patients over the age of 50 years (153 vs 142 mmHg), and absent among patients under 50 years (140 vs 139 mm Hg). Blood pressures during sleep did not differ between the two groups (121/76 vs 123/77 mm Hg). We conclude that, among white hypertensives above the age of 50 years, smokers maintain a higher daytime ambulatory systolic blood pressure than nonsmokers even though blood pressure measured in the office is similar.

Adult↗
PubMed1991

Captopril renography in the diagnosis of renal artery stenosis: accuracy and limitations.

PURPOSE: The purpose of this study was to determine the sensitivity, specificity, and clinical usefulness of renography performed in combination with captopril administration ("captopril renography") in diagnosing renal artery stenosis. PATIENTS AND METHODS: Fifty-five patients with suspected renal artery stenosis underwent renography prior to performance of renal angiography. Renography was performed on two consecutive days using technetium-99m-diethylenetiamine pentaacetic acid (DTPA) as an index of glomerular filtration rate and iodine-131-orthoiodohippurate (OIH) as an index of renal blood flow. Captopril (25 mg orally, crushed) was administered 1 hour before the second study. Renal artery stenosis was defined as a stenosis exceeding 70%. Renographic criteria were then established, retrospectively, to differentiate renal artery stenosis from essential hypertension based on (1) asymmetry of function and (2) the presence of captopril-induced changes. RESULTS: Renal artery stenosis was detected in 35 of 55 patients (21 with unilateral and 14 with bilateral stenosis). Three criteria were established for diagnosing renal artery stenosis: (1) a percent uptake of DTPA by the affected kidney of less than 40% of the combined bilateral uptake, (2) a delayed time to peak uptake of DTPA, which was more than 5 minutes longer in the affected kidney than in the contralateral kidney, (3) a delayed excretion of DTPA, with retention at 15 minutes, as a fraction of peak activity, more than 20% greater than in the contralateral kidney. The presence of one or more of these criteria was diagnostic of renal artery stenosis, with a sensitivity and specificity of 71% and 75%, respectively before captopril administration, and 94% and 95% after captopril administration. Lesser degrees of asymmetry (i.e., uptake of 40% to 50%) had very poor diagnostic specificity. Among patients with bilateral stenoses, asymmetry identified the more severely affected kidney, but the presence or absence of stenosis in the contralateral kidney could not be reliably determined. When pre- and post-captopril studies were compared, the presence of captopril-induced scintigraphic changes was a highly specific finding for renal artery stenosis, but occurred in only 51% of the cases. OIH scintigraphy provided similar results, with slightly lower sensitivity and specificity. CONCLUSION: Asymmetry of DTPA uptake, time to peak uptake, or retention seen on a single post-captopril renogram is a highly sensitive and specific finding in detecting renal artery stenosis but does not distinguish unilateral from bilateral disease. If renograms are obtained both before and after captopril administration, the presence of captopril-induced change is a highly specific finding for the detection of renal artery stenosis, but the sensitivity of this finding is low.

Antihypertensive Agents↗
PubMed1991

Clinic and ambulatory blood pressure measurements for the evaluation of borderline hypertension in smokers and non-smokers.

Hypertension can be diagnosed only by blood pressure measurement, but conventional clinic measurement is subject to two major sources of error, first from the inherent variability of blood pressure, and second from the white coat effect, that is the increase of pressure that occurs in the presence of a physician. Ambulatory monitoring avoids both of these problems. Although smoking has been shown to raise blood pressure acutely, population studies have failed to show a sustained effect. To resolve this paradox, we compared clinic and ambulatory pressures in smokers and non-smokers. Clinic pressures were the same, but smokers had significantly higher daytime ambulatory pressures, than non-smokers, particularly in subjects over the age of 50. No differences in nighttime pressures were observed.

Adult↗
PubMed1989

Assessment of the effects of alpha- and beta-blockade in hypertensive patients who smoke cigarettes.

A 24-week, crossover, comparison study was conducted to observe the effects of alpha-blockade with prazosin and beta-blockade with propranolol on blood pressure and plasma lipoprotein levels in 15 hypertensive cigarette smokers. Before treatment, mean sitting blood pressure was 140/100 mm Hg and rose to 147/105 mm Hg after the patients smoked two cigarettes. Treatment with prazosin and propranolol lowered sitting blood pressure to 127/89 mm Hg and 129/91 mm Hg, respectively (not significant), and did not alter the pressor response to smoking. The total cholesterol level at baseline was 207.3 +/- 11.0 mg/dl. This increased to 210.5 +/- 10.2 mg/dl with propranolol treatment and decreased to 201.0 +/- 11.1 mg/dl with prazosin treatment. The low-density lipoprotein cholesterol level was 132.5 +/- 8.1 mg/dl at baseline, 136.9 +/- 8.3 mg/dl with propranolol treatment, and 129.4 +/- 9.0 mg/dl with prazosin treatment (0.05 less than p less than 0.10 between-group comparison). The data indicated that whereas prazosin and propranolol are equally effective in controlling blood pressure in hypertensive cigarette smokers, effects on plasma lipoproteins also may need to be considered when selecting a first-step antihypertensive agent in this coronary-prone population.

Adult↗
PubMed1989

Go for the gold.

Explore the source record for details and available documents.

Aged↗
PubMed1985

Plasma epinephrine concentration in healthy men: correlation with systolic pressure and rate-pressure product.

Relations among plasma epinephrine, norepinephrine and renin activity and systolic pressure, diastolic pressure, heart rate and the product of heart rate and systolic pressure (rate-pressure product) were evaluated in 31 healthy men whose arterial pressure spanned the range from normal to mildly elevated. Measurements were made during 60 minutes with the patient in the supine position and during 10 minutes of quiet standing. In the supine position, highly significant regressions were found between systolic pressure or rate-pressure product and plasma epinephrine, but not between these variables and norepinephrine or renin activity. A weakly significant correlation was also found between heart rate and norepinephrine. On standing, norepinephrine and epinephrine increased significantly. In this position, rate-pressure product was significantly related by regression analysis only with plasma epinephrine. Weakly significant correlations between systolic pressure and epinephrine and between heart rate and norepinephrine and epinephrine were also found. Plasma renin activity was not significantly correlated with arterial pressure, heart rate or rate-pressure product in either position. These results suggest that plasma epinephrine is a determinant of systolic pressure when postural reflexes are minimized and that epinephrine may participate in control of cardiac work load, as reflected by rate-pressure product in the absence of exercise or definable stress.

Adolescent↗
PubMed1984

Hypertensive crisis caused by hypoglycemia and propranolol.

In a patient with severe hypertension in association with insulin-induced hypoglycemia and prior therapy with propranolol hydrochloride, intravenous 50% dextrose significantly reduced arterial pressure on two occasions. Subsequent reduction of arterial pressure was observed with prazosin hydrochloride, an alpha-receptor antagonist. The hypertensive episode may have been caused by hypoglycemia stimulating excessive release of epinephrine. In the presence of vascular beta 2-receptor blockade by propranolol, the hypertensive action of epinephrine was mediated by vascular alpha-receptors. When beta-antagonists must be used in insulin-dependent diabetic patients, beta 1-selective antagonists appear to be a better choice.

Adult↗
PubMed1975

Lattice and rodlet nuclear inclusions in Merkel cells in rabbit epidermis.

A latticee or rodlet inclusion is occasionally observed in the nucleus of a Merkel cell. The lattice has the external form of a plaque or band and internally consists of alternating parallel wide and narrow layers. Filaments in wide layers run in at least two directions across the short dimension of the inclusion. In contrast, the rodlet is a bundle of parallel filaments running the long dimension of the inclusion. Filaments in lattices and rodlets possibly contract and agitate the highly folded nucleus of the Merkel cell.

Animals↗
PubMed1975

Trichophyton rubrum infections according to age, anatomical distribution and sex.

Trichophyton rubrum caused 72.9% of the cases of dermatophytosis observed in a sample of caucasoids from Philadelphia. Tinea pedis was found in 84% of the female and male patients with dermatophytosis. Tinea manuum occurred with equal frequency in both sexes whereas tinea unguium was more prevalent in females. Tinea cruris occurred almost exclusively in males. Infections of two or more anatomical sites were observed more frequently in males. The data are compared with those reported by Rosman (1966) from a similar study done in Copenhagen.

Adolescent↗
PubMed1975

Systemic amyloidosis in mice inoculated with lyophilized Candida cells.

Injection of lyophilized Candida albicans or C. parapsilosis cells induced amyloidosis in outbred CFW mice. The disease process was irreversible, and a significant number of animals died of systemic amyloidosis within 400 days after the last treatment. The techniques described may represent a model system for the study of systemic amyloidosis.

Amyloid↗