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Paradoxically, nitric oxide (NO) has been found to exhibit cytotoxic, antiproliferative, or cytoprotective activity under different conditions. We have utilized Salmonella mutants deficient in antioxidant defenses or peptide transport to gain insights into NO actions. Comparison of three NO donor compounds reveals distinct and independent cellular responses associated with specific redox forms of NO. The peroxynitrite (OONO-) generator 3-morpholinosydnonimine hydrochloride mediates oxygen-dependent Salmonella killing, whereas S-nitrosoglutathione (GSNO) causes oxygen-independent cytostasis, and the NO. donor diethylenetriamine-nitric oxide adduct has no antibacterial activity. GSNO has the greatest activity for stationary cells, a characteristic relevant to latent or intracellular pathogens. Moreover, the cytostatic activity of GSNO may best correlate with antiproliferative or antimicrobial effects of NO, which are unassociated with overt cell injury. dpp mutants defective in active dipeptide transport are resistant to GSNO, implicating heterolytic NO+ transfer rather than homolytic NO. release in the mechanism of cytostasis. This transport system may provide a specific pathway for GSNO-mediated signaling in biological systems. The redox state and associated carrier molecules are critical determinants of NO activity.

Two samples of Amaranthus cruentus harvested in 1987 (sample A) and 1990 (sample B) were studied. Whole and refined flours were obtained. The whole flours contained 14.6 and 12.6% protein and 6.6 and 7.3 ether extraction, respectively. Both samples contained significant levels of Ca, P, Mg and K. Amaranth oil contained 19% palmitic acid, 3.4% stearic acid, 3.4% stearic acid, 34% oleic acid and 33% linoleic acid. Docosaenoic acid (C22:1) was present at the level of 9%. The ratio of saturated to unsaturated fatty acids was approximately 1:3. The level of crude fiber was 3.7% in the whole flours and 2.4% in the refined ones. Biological protein quality of flours was measured in the rat by the net protein ratio (NPR) method. The NPR values of the four materials tested ranged from 3.04 to 3.20 (NS), as compared with 4.08 for casein. These values are equivalent to 75-78% of the standard protein. Blends of raw wheat flour and whole amaranth flour fed to rats produced a good complementary effect between proteins, as shown by PER test. Wheat flour gave a poor PER value of 0.54. However, this figure increased with every increment of amaranth flour reaching a value of 2.15 for the blend 25:75. The PER for the amaranth diet (0:100) was 1.94 (casein 2.77). As expected, the extrusion process applied to the wheat/amaranth and corn/amaranth mixtures improved the biological quality of the protein. The wheat flour diet (100:0) gave a PER value of 1.64. Mixture 90:10 produced a low non significant increase in the protein quality.(ABSTRACT TRUNCATED AT 250 WORDS)

Dissection of the inferior wall of the right ventricle during the acute phase of myocardial infarction with right ventricular involvement is a mechanical complication which has been recently identified, the diagnosis being almost exclusively post-mortem. The authors report the clinical, echocardiographic and pathological features of myocardial dissection in four patients. Between 1985 and 1988, the diagnosis of myocardial dissection was made by echocardiography in 4 patients aged 77 to 80 years, admitted to hospital for an acute inferior wall myocardial infarction. All 4 patients had signs of acute right ventricular failure indicating right ventricular necrosis and a loud systolic murmur at the left sternal border; 2 patients were in shock. The ECG showed signs of inferior wall infarction with, in 2 patients, electrical changes suggestive of right ventricular involvement. Echocardiography showed dissection of the inferior wall of the right ventricle as a pulsatile, echo-free space in the diaphragmatic wall of the right ventricle which appeared to obstruct right ventricular ejection in end systole to a variable degree. The outcome was fatal in all cases with death resulting from refractory myocardial failure. Pathological analysis confirmed biventricular inferior wall infarction also involving the posterior part of the interventricular system, the site of a small tear on the left side which communicated with a neo-cavity dissecting the RV posterior wall. The right coronary artery was totally occluded in all cases. The anatomical lesions were fully concordant with the echocardiographic data: the dissection filled with blood from the left ventricle at each systole creating a pulsatile space in the diaphragmatic wall of the ventricle obstructing ejection.

This study focused on peer sensitivity to differences in social behaviors between hyperactive and normal comparison peers and, especially, to medication-related behavioral differences. In Study 1, normal sixth graders rated videotapes of normal and hyperactive boys playing a social interaction game. Half of the hyperactive boys were taking methylphenidate, and the other half placebo. In Study 2, fourth- and sixth-grade children rated a different sample of hyperactive boys (seen on both methylphenidate and placebo) playing the same interaction game. Hyperactive boys taking placebo were perceived as exhibiting more externalizing problem behaviors than either medicated hyperactive boys or comparison boys. The medication effects were robust, spanning many behavioral domains and emerging consistently across the 2 studies. There were few grade or gender differences. Discussion focused on children's detection of treatment-related differences in the social behaviors of their peers, as well as on the imperfect relation between social behavior and social standing.

Components of mycobacterial cell wall(s) (CW) attached to oil droplets were evaluated for their ability 1) to inhibit the growth of line-10 tumor transplants in the skin of syngeneic guinea pigs when inoculated together with 10(6) tumor cells (suppression experiments) and 2) to regress established 7-day-old intradermal tumors and eradicate microscopic lymph node metastases upon injection into the tumors (regression experiments). CW and cell-wall skeleton (CWS) preparations from Mycobacterium phlei, a fast-growing saprophyte of group IV of the atypical mycobacteria, suppressed tumor growth in essentially all animals when 37.5-mug doses were administered; at a dose of 300 mug, they cured 50-60% of the animals in regression tests. The addition of 300 mug of a purified trehalose mycolate, isolated from M. tuberculosis strain Aoyama B, to 300 mug M. phlei CW or CWS preparations significantly increased their tumor regressive potency to provide cure rates to about 90%. Because M. phlei can be propagated more readily, it can be used advantageously in place of BCG to prepare stable, non-living immunologic adjuvants of defined composition and consistently high potency to meet the need for standards with minimal residual malignant disease.