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S Solomon

Publications and source records attributed to S Solomon.

At least 19 recordsLinked to original sources
PubMed1992

Purification of cationic cystine-rich peptides from rat bone marrow. Primary structures and biological activity of the rat corticostatin family of peptides.

Seven cationic, cystine-rich peptides of 29 to 32 amino acid residues have been purified from extracts of rat bone marrow (R-1, R-1a, R-1b, R-2, R-3, R-4 and R-5). Structural analysis clearly indicated that all seven peptides belong to the corticostatin/defensin family of leukocyte-derived peptides known to participate in oxygen-independent killing of phagocytosed bacteria. For R-1 to R-5, six cysteine residues were found at characteristic and highly conserved positions. R-1a and R-1b were partially characterized and appear to be structural variants of R-1. Aside from the conserved cysteines, there is a remarkable degree of structural diversity evident within the sequences of those members of the corticostatin/defensin family characterized so far. The structures of the peptides that we have purified can be compared directly with the sequences obtained for rat defensins isolated from extracts of peritoneal neutrophils (Lehrer, Ganz and Selsted, Cell, 64 (1991) 229-230). Some discrepancies are apparent which can be explained in terms of proteolytic cleavage of several of these peptides at both amino- and carboxyl-termini. The corticostatins owe their bioactivity to their ability to compete with corticotropin for occupancy of the corticotropin receptor (Zhu, Hu, Mulay, Esch, Shimasaki and Solomon, Proc. Natl. Acad. Sci. USA, 85 (1988) 592-596). The potency of these peptides can be expressed in terms of their capacity to inhibit the steroidogenic response of isolated rat adrenocrotical cells half-maximally stimulated by corticotropin (i.e., at the ED50 concentration for corticotropin in this assay, namely 33 pM). In this assay, the rat peptides R-1, R-2 and R-3 were shown to be inactive. In contrast, the more cationic peptides R-4 and R-5 were found to inhibit steroidogenesis. R-4 was somewhat less active than rabbit corticostatin (IC50 25 nM) showing an IC50 value of 50 nM. R-5 appeared to be significantly less potent than R-4. The lower yield of R-5 precluded an accurate estimate of the corticostatic potency of this peptide. R-4 differs in structure from R-5 in having an arginine to serine substitution at position 7. It can be concluded that an arginine at this position accounts, at least in part, for the corticostatic activity of R-4.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenocorticotropic Hormone↗
PubMed1992

Dose ranging efficacy and safety of subcutaneous sumatriptan in the acute treatment of migraine. US Sumatriptan Research Group.

Sumatriptan, a specific serotonin1-like receptor agonist, was studied in the acute treatment of migraine. Two hundred forty-two adult migraineurs participated in a randomized, double-blind study in which one dose of 1, 2, 3, 4, 6, or 8 mg of subcutaneous sumatriptan succinate was evaluated in sequential ascending fashion. At each dose level, a placebo group was included. Efficacy was defined as reduction of moderate or severe pain to mild or no pain, without the use of rescue medication. Headache relief rates showed an approximate dose-response relationship and at 1 hour were as follows: placebo, 24%; 1 mg, 43%; 2 mg, 57%; 3 mg, 57%; 4 mg, 50%; 6 mg, 73%; and 8 mg, 80%. Relief of nausea and improvement in clinical disability were also approximately dose related. Adverse events were dose related; the most common types were injection site reactions and tingling. The 6-mg dose was as effective as the 8-mg dose but was associated with fewer adverse effects and so is optimal.

Adult↗
PubMed1992

Protein glycation: effects upon protein recognition by the proximal tubule.

Reabsorption of 125I labeled unmodified and glycated albumin by the proximal tubule was studied using micropuncture technique in wistar rats of different ages. The data show a significant reabsorption of unmodified albumin while the glycated albumin was virtually excluded from reabsorption process. Among different explanations considered, we think molecular charge of the protein seems to be a key factor for the altered recognition of glycated albumin by the proximal tubule.

Animals↗
PubMed1992

Migraine visual auras. A medical update for the psychiatrist.

Auras of visual aberrations as well as other neurological disturbances including somatosensory and perceptual symptoms that precede a headache distinguish migraine with aura (classic migraine) from migraine without an aura (common migraine) and other varieties of headache. Visual auras that characterize migraine with aura can be classified and distinguished from other neurologic and psychiatric causes of visual aberrations. Examples of migraine visual auras, which are often described but rarely shown in the medical literature, are presented and their mechanism is discussed.

Hallucinations↗
PubMed1992

Impaired endothelium-mediated vasodilation in the peripheral vasculature of patients with congestive heart failure.

Impaired endothelial-dependent vasodilation has been demonstrated in two animal models of congestive heart failure and in the coronary circulation of patients with idiopathic dilated cardiomyopathy. To determine whether this impairment contributes to the abnormal peripheral vasomotor tone in patients with congestive heart failure, the local vascular response to intraarterial infusions of graded concentrations (10(-8) M to 10(-5) M) of acetylcholine (an endothelial-dependent vasodilator) and nitroglycerin (a direct-acting vasodilator) was studied in the superficial femoral artery of 19 patients with congestive heart failure (New York Heart Association classes I to IV) and 6 age-matched normal control subjects. The local vascular response was determined from the arterial blood flow velocity pattern obtained by transcutaneous Doppler ultrasonography. Acetylcholine, 10(-5) M, induced a pattern characteristic of vasodilation in all six normal subjects; mean blood flow velocity for the group significantly increased from 11.9 +/- 2.7 to 44.8 +/- 20.9 cm/s (p less than 0.05). In contrast, the same dose of acetylcholine induced a blood flow velocity pattern characteristic of vasodilation in only 4 of the 19 patients with congestive heart failure. Group mean blood flow velocity did not change significantly. Nitroglycerin, 10(-7) M, induced vasodilation in all 6 normal subjects but in only 1 of 19 patients. Nitroglycerin, 10(-5) M, was administered to 10 patients; all 10 demonstrated a pattern characteristic of vasodilation. Thus, acetylcholine-mediated endothelial-dependent vasodilation appears to be impaired in the peripheral vasculature of patients with congestive heart failure. Both endothelial dysfunction and abnormal vascular smooth muscle responsiveness may contribute to abnormal peripheral vasomotor tone.

Acetylcholine↗
PubMed1992

Activation of protein kinase C stimulates collagenase production by cultured cells of the cervix of the pregnant guinea pig.

OBJECTIVE: Dilatation of the uterine cervix at parturition is achieved by an estrogen-induced, collagenase-mediated degradation of type I collagen in the cervix. The objective was to test the hypothesis that collagenase production in the cervix of pregnant guinea pig in culture is mediated by activation of protein kinase C. STUDY DESIGN: The effects of 17 beta-estradiol, prostaglandin F2 alpha, or activation of protein kinase C by phorbol-12-myristate-13-acetate, 1-stearoyl-2-arachidonyl-sn-glycerol and phospholipase C on collagenase production was studied with primary monolayer cultures of cervical cells from Hartley guinea pigs at 50 days' gestation. Results are analyzed for statistical significance with analysis of variance. RESULTS: Collagenase production is increased twofold to threefold by 17 beta-estradiol, prostaglandin F2 alpha, or activation of protein kinase C. The observed stimulation of collagenase production by 17 beta-estradiol and prostaglandin F2 alpha was blocked by the protein kinase C inhibitor 1-(5-isoquinoline sulfonyl) 2-methylpiperazine dihydrochloride. CONCLUSION: Collagenase production in cultured cervical cells of pregnant guinea pig is stimulated by activation of protein kinase C.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1992

Terror management and tolerance: does mortality salience always intensify negative reactions to others who threaten one's worldview?

Terror management research has shown that reminding Ss of their mortality leads to intolerance. The present research assessed whether mortality salience would lead to increased intolerance when the value of tolerance is highly accessible. In Study 1, given that liberals value tolerance more than conservatives, it was hypothesized that with mortality salience, dislike of dissimilar others would increase among conservatives but decrease among liberals. Liberal and conservative Ss were induced to think about their own mortality or a neutral topic and then were asked to evaluate 2 target persons, 1 liberal, the other conservative. Ss' evaluations of the targets supported these hypotheses. In Study 2, the value of tolerance was primed for half the Ss and, under mortality-salient or control conditions, Ss evaluated a target person who criticized the United States. Mortality salience did not lead to negative reactions to the critic when the value of tolerance was highly accessible.

Attitude to Death↗
PubMed1992

Why do people need self-esteem? Converging evidence that self-esteem serves an anxiety-buffering function.

Three studies were conducted to assess the proposition that self-esteem serves an anxiety-buffering function. In Study 1, it was hypothesized that raising self-esteem would reduce anxiety in response to vivid images of death. In support of this hypothesis, Ss who received positive personality feedback reported less anxiety in response to a video about death than did neutral feedback Ss. In Studies 2 and 3, it was hypothesized that increasing self-esteem would reduce anxiety among individuals anticipating painful shock. Consistent with this hypothesis, both success and positive personality feedback reduced Ss' physiological arousal in response to subsequent threat of shock. Thus, converging evidence of an anxiety-buffering function of self-esteem was obtained.

Adaptation, Psychological↗
PubMed1992

Evaluation of chronic daily headache--comparison to criteria for chronic tension-type headache.

The purpose of this study was to evaluate the adequacy of the International Headache Society (IHS) criteria for chronic tension-type headache and, if appropriate, suggest modifications of the IHS classification. We evaluated 100 consecutive patients with chronic daily headache. Approximately two-thirds of our patients fulfilled the criteria for chronic tension-type headache. Most of the patients who failed to meet the criteria did so because they had more than one migrainous feature. Approximately 50% of patients took excessive amounts of analgesic medication. We conclude that the IHS criteria should be modified to include chronic daily headache evolving from migraine; subtypes with and without medication overuse should be distinguished.

Adolescent↗
PubMed1992

Chronic paroxysmal headache: two cases with cerebrovascular disease.

Paroxysmal headaches often occur in benign headache disorders such as episodic cluster headache, chronic paroxysmal hemicrania (CPH) and episodic paroxysmal hemicrania. We report 2 patients with paroxysmal headaches occurring in association with cerebrovascular disease. The first patient had paroxysmal headaches from an arteriovenous malformation which resolved following embolization. In the second patient, headache followed a cerebral infarction and responded to treatment with indomethacin. We suggest that vascular disease may cause paroxysmal headaches resembling CPH. Patients with an atypical presentation of CPH warrant a neuroimaging procedure.

Adult↗
PubMed1992

Hemicrania continua: attacks may alternate sides.

Hemicrania continua (HC) is characterized by a continuous unilateral headache of moderate severity, occurring in 2 patterns; a continuous form in which headaches persist continuously without remission for years, and a remitting form, consisting of headache phases separated by periods of pain-free remission. The remitting form of HC must be distinguished from other cyclical headache disorders such as episodic paroxysmal hemicrania and episodic cluster headache. Characteristically, the headache of HC is unilateral and without sideshift. We now report a case of HC in which headaches alternate sides.

Aged↗
PubMed1992

Childhood onset cluster headaches.

Cluster headaches are rare in childhood. We identified 35 patients with cluster headaches starting at or before 18 years of age, including 7 patients with onset prior to age 10. All patients met the criteria of the International Headache Society for episodic or chronic cluster headaches. Patients experienced cluster headaches for as long as 20 years before seeking medical attention and required many medical contacts to establish the correct diagnosis. The clinical features of cluster headaches during childhood were similar to those which typically occur in adult life. Cluster headache patterns changed over 18 years of follow up. The frequency and duration of cluster periods increased in 14 subjects. The frequency of single headache attacks during cluster periods also increased in a similar number of subjects. We conclude that cluster headaches starting in childhood or adolescence closely resemble the adult form of the disease. In many patients, the frequency and duration of cluster periods and the frequency of the individual headache episodes increased over time. Cluster headache represent a treatable under-recognized cause of severe headaches in childhood and adolescence.

Adolescent↗
PubMed1992

Clinical features of chronic daily headache.

Patients with chronic daily headaches are commonly encountered in headache specialty centers but their clinical characteristics have rarely been documented. We studied 100 consecutive patients with chronic daily headache to determine their presenting characteristics and other associated features. Half of the patients described their headache as a steady ache but throbbing pain was reported in about one third. About half estimated the degree of pain as moderate but one third claimed the typical pain was severe. A consistently unilateral site was noted in only 2 percent. Associated features characteristic of migraine were often noted: Including photophobia (37 percent), photophobia (42 percent), and nausea (24 percent). Many also reported aggravating and ameliorating factors commonly associated with migraine. We conclude that the manifestations of chronic daily headache are extremely diverse, probably reflecting the heterogeneous mechanisms which underlie this condition.

Adolescent↗
PubMed1992

Isolation and mode of action of rabbit corticostatic (antiadrenocorticotropin) peptides.

Corticostatic peptides are a family of arginine-rich cysteine-rich peptides that inhibit ACTH-stimulated corticosterone (B) production in rat adrenal cell suspensions. In this communication we describe a new method for the facile isolation and purification of these basic peptides from rabbit adult lung. We then describe the isolation and sequences of the four rabbit peptides, CSI, CSII, CSIII, and CSIV, and compare their biological activities in the ACTH (150 pg/ml) inhibition assay. CSI is by far the most potent of the four peptides. Using CSI as a model, we then studied its effects on the proximal and distal parts of the pathway leading to the generation of cAMP. CSI had no effect on (Bu)2cAMP action on forskolin or cholera toxin in their ability to mimic ACTH and increase B production in rat adrenal cells, nor did CSI have any effect on the stimulation of B production by pertussis toxin. Endogenous cAMP stimulated by ACTH decreased after the addition of CSI, which pointed to the inhibition of ACTH binding to explain the mode of action of this corticostatin. Displacement of the specific binding of labeled ACTH by CSI and the ACTH antagonist ACTH-(6-24) was determined, and indeed, CSI did displace ACTH from its binding site. The question of what portion of the ACTH molecule was involved in the action of CSI was answered by studying ACTH-(1-13) acetyl amide (alpha MSH) and ACTH-(1-18) amide. CSI had no effect on alpha MSH stimulation of B production, but did lower the production of B stimulated by ACTH-(1-18) amide. Therefore, CSI must act on ACTH-(14-18), which is part of the so-called address region of ACTH, which is -Gly14-Lys15-Lys16-Arg17-Arg18-, the very basic part of the molecule. These results indicate that CSI acts by competing with ACTH for its binding receptor on the adrenal cell and that this competition is confined to amino acids 14-18 of the molecule when it is bound to the receptor.

Adrenal Glands↗
PubMed1992

Episodic paroxysmal hemicrania: two new cases and a literature review.

Episodic paroxysmal hemicrania (EPH) is a rare disorder characterized by discrete bouts of hemicranial headache separated by headache-free remissions. Although EPH resembles episodic cluster headache in the location and quality of pain as well as the pattern of associated autonomic features, it is distinguished by the greater frequency and shorter duration of individual headaches. Differentiation of these disorders is important because EPH almost invariably responds to treatment with indomethacin but not to standard cluster headache therapy.

Adult↗
PubMed1992

Critical analysis of methods for assessing regional blood flow and their reliability in clinical medicine.

The advantages and inadequacies of the currently available techniques to measure regional blood flow in the lower limbs are being reviewed. Thermodilution technique and local 133xenon washout technique have the advantage of allowing determination of blood flow during exercise, while venous occlusion plethysmography and pulsed-Doppler duplex ultrasonography only allow determination of blood flow at rest. Overall, measurements of lower limb blood flow are not highly reproducible by any technique, and the variability in measurements of regional blood flow should lead to careful interpretation of derived parameters such as vascular conductance and resistance. Determination of vascular input impedance by Fourier analysis of pressure data, recorded with high fidelity catheter, and flow velocity measurements obtained transcutaneously by Doppler ultrasonography, may offer a more accurate quantitative analysis of the characteristics of the lower limb vascular system.

Catheterization, Peripheral↗