Changes in the ultraviolet (UV) absorption spectra of nicotinamide adenine dinucleotide (NAD), of its synthetic analogues, and of adenosine and its derivatives in the presence of high concentrations of orthophosphate were studied.
The role of the carboxamide group of the nicotinamide moiety of NAD on these spectral changes was investigated by replacing that group with an acetyl or aldehyde group. The effect of the 6-amino group of the purine was investigated by studying the interaction of deamino-NAD and various adenosine derivatives with orthophosphate. 2,4-Dinitrophenol was also found to give a charge transfer complex with phosphate. Molar extinction coefficients (E) and association constants (K) of these charge transfer reactions were determined.
This is a preliminary report of a method of digital computer analysis of the electromyogram recorded from twenty sites in biceps brachial during fixed voluntary effort. The results in a group of normal subjects have been compared with those in patients with neuromuscular disease. Three parameters have proved of value in differentiating normal subjects from those with neurogenic disease.
The effects on active social interaction of acute and chronic dosage with diazepam (1 mg/kg), desmethyldiazepam (2 mg/kg), and chlor-desmethyl-diazepam (0.125 mg/kg) were studied in pairs of mice. The mice were tested under either high or low levels of illumination. In all cases acute drug treatment significantly reduced social interaction, but this was not seen with chronic treatment (9 days). Two of the drugs, diazepam and desmethyldiazepam, showed an anxiolytic action, i.e., these drugs resulted in significantly less variation in social interaction with the change in light levels, compared with vehicle-injected controls.
The osmotic fragility of red blood cells is influenced by even modest environmental changes. Consequently, the technical procedure must be strictly standardized. This implies that temperature equilibrium of the buffered salt solutions should be reached prior to the addition of blood.
Furthermore, since erroneous statements concerning the composition of phosphate buffers regularly used to secure correct pH of the salt solutions have repeatedly appeared in the literature, pH control of such solutions prior to use becomes essential. When the annulus is made to swell the attached hairs are pushed to their erect position. The clinical and postmortem findings in a 4-month-old infant with polyarteritis nodosa are presented. The relationship of this condition to mucocutaneous lymph node syndrome (MLNS) is discussed, and the relevant literature is reviewed. Cholesterol emboli have only recently been recognized as a pathological entity and their clinical picture is still not clearly defined. A case is reported of a patient presenting signs of a severe systemic affection with distal arteriolitis and also general and biological signs of a severe inflammatory process having the particular characteristic of apparent corticoid sensitivity. The patient died following ischemic necrosis of the sigmoid from perforation and peritonitis, also related to the presence of cholesterol emboli. The specific activities, the Km values, and the elution patterns on DEAE 52 and Sephadex G-150 columns of six lysosomal enzymes in human liver during development were studied. The levels of total beta-D-glucuronidase and N-acetyl-beta-D-glucosaminidase activities in childhood liver were higher than those in fetal liver. The Km values of beta-D-glucuronidase and beta-D-galactosidase in fetal liver were about ten times higher than those in childhood liver.
The elution patterns on DEAE 52 of beta-D-glucuronidase and on Sephadex G-150 of alpha-D- and beta-D-galactosidases changed with aging. It is suggested that lysosomal enzymes related to degradation of gangliosides and glycosaminoglycans change during development. An assay which uses two differentially labeled cell populations was used to characterize the preferential localization of passively transferred syngeneic cells immunized to specific alloantigens.
Splenocytes cytotoxic to B10.D2 and B10.BR alloantigens were harvested from (C57BL/6 X A/J)F1 (B6AF1) donors bearing acutely rejected skin allografts. One population was labeled in vitro with 3H-thymidine and the other with 14C-thymidine. into B6AF1 hosts bearing 5-day-old skin grafts from B10.D2 and B10.BR donors. After 48 hr the mice were killed, and the relative amount of cells present in the skin grafts and draining axillary lymph nodes was derived by comparing the 3H:14C ratios of the harvested tissues. The results of these studies indicated that cytotoxic splenocytes harvested from donors bearing acutely rejected skin allografts preferentially localize to the relevant skin allograft after passive systemic transfer. The homing behavior of these splenocytes was augmented by T cell enrichment and significantly diminished by pretreatment with anti-Thy-1.2 serum plus rabbit complement. There was no evidence of preferential homing within the draining axillary lymph nodes.