National surveillance of dialysis associated diseases in the United States, 1995

Many fundamental and hot band absorption lines of 28Si35Cl+, 28Si37Cl+, 29Si35Cl+, and 30Si35Cl+ have been detectedbetween 630 and 700 cm-1 in a SiCl4/He discharge using diode laser velocity modulation spectroscopy. The datahave been fitted to give seven mass independent coefficients Ukl. The derived spectroscopic constants for 28Si35Cl+ include omegae = 678.24316(18) cm-1 and Be = 0.2870288(14) cm-1. The equilibrium internuclear distance is re =1.9439105(46) ?. The equilibrium dissociation energy calculated from Dunham's expanded Morse potential is De =49 431(57) cm-1. Copyright 1998 Academic Press.     

Pediatric hepatic trauma: does clinical course support intensive care unit stay?

PURPOSE: The objective of this study is to determine if grade of liver injury predicts outcome after blunt hepatic trauma in children and to initiate analysis of current management practices to optimize resource utilization without compromising patient care. METHODS: A retrospective review of 36 children who had blunt hepatic trauma treated at a pediatric trauma center from 1989 to present was performed. Hepatic injuries graded (AAST Organ Injury Scaling) ranged from grade I to IV. Injury Severity Score (ISS), Glasgow Coma Score (GCS), transfusion requirements, liver transaminase levels, associated injuries, intensive care unit (ICU) length of stay, and survival were analyzed. RESULTS: Mean (+/-SEM) age was 6.6+/-0.8 years, mean grade of hepatic injury was 2.4+/-0.2, mean ISS was 17+/-2.6, mean GCS was 13+/-1, and mean transfusion was 15.4 mL/kg of packed red blood cells (PRBC). There were three deaths with a mean ISS of 59+/-9 and a mean GCS of 3+/-0. Death was not associated with a high-grade liver injury, survivors versus nonsurvivors, 2.3+/-0.2 versus 2.7+/-0.3, but was associated with ISS, 13+/-1.4 versus 59+/-9 (P = .005) and GCS, 14+/-1 versus 3+/-0 (P = .005). Only one patient (grade III, ISS = 43) underwent surgery. There were no differences in mean ISS or GCS between grades I to IV patients. The hepatic injury grades of patients requiring transfusion versus no transfusion were significantly different, 3.4+/-0.2 versus 2.2+/-0.2 (P = 0.04). Abused patients had high-grade hepatic injuries and significant laboratory and clinical findings. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly higher in grade III and IV injuries than in grades I and II, 1,157+/-320 versus 333+/-61 (P= .02) and 1,176+/-299 versus 516+/-86 (P= .04), respectively. No children with grade I or II injury had a transfusion requirement or surgical intervention. There were no liver-related complications. CONCLUSIONS: Mortality and morbidity rates in pediatric liver injuries, grades I to IV, correlate with associated injuries not the degree of hepatic damage. ALT, AST, and transfusion requirements are significantly related to degree of liver injury. Low-grade and isolated high-grade liver injuries seldom require transfusion. Blunt liver trauma rarely requires surgical intervention. In retrospect, the need for expensive ICU observation for low-grade and isolated high-grade hepatic injuries is questionably warranted.     

A Golgi localization signal identified in the Menkes recombinant protein

Menkes disease arises from a genetic impairment in copper transport. The gene responsible for the phenotype has been identified as a copper transporting ATPase ( ATP7A ). Recently, the protein encoded by the ATP7A gene has been localized to the Golgi complex. In order to investigate the role of the Menkes disease protein in copper transport, recombinant constructs containing both the full-length open reading frame and an alternatively spliced form have been successfully expressed and localized in mammalian cells. Other studies of a patient with occipital horn syndrome, an allelic variant of Menkes disease, have demonstrated that only this alternatively spliced isoform and not the full-length form is expressed in this patient. The milder form of this patient's phenotype suggests that the alternatively spliced isoform has some functional role in copper transport. In the present study the full-length recombinant Menkes protein was shown by immunofluorescence to localize to the Golgi apparatus and the alternatively spliced form, lacking sequences for transmembrane domains 3 and 4 encoded by exon 10, was shown to localize to the endoplasmic reticulum. Using sequences from exon 10 fused to a non-Golgi reporter molecule, a 38 amino acid sequence containing transmembrane domain 3 of the Menkes protein was found to be sufficient for localization to the Golgi complex. Therefore, the protein sequence encoded by exon 10 may be responsible for this differential localization and both isoforms may be required for comprehensive transport of copper within the cell.     

Steady-state cerebral glucose concentrations and transport in the human brain

Understanding the mechanism of brain glucose transport across the blood-brain barrier is of importance to understanding brain energy metabolism. The specific kinetics of glucose transport have been generally described using standard Michaelis-Menten kinetics. These models predict that the steady-state glucose concentration approaches an upper limit in the human brain when the plasma glucose level is well above the Michaelis-Menten constant for half-maximal transport, Kt. In experiments where steady-state plasma glucose content was varied from 4 to 30 mM, the brain glucose level was a linear function of plasma glucose concentration. At plasma concentrations nearing 30 mM, the brain glucose level approached 9 mM, which was significantly higher than predicted from the previously reported Kt of approximately 4 mM (p < 0.05). The high brain glucose concentration measured in the human brain suggests that ablumenal brain glucose may compete with lumenal glucose for transport. We developed a model based on a reversible Michaelis-Menten kinetic formulation of unidirectional transport rates. Fitting this model to brain glucose level as a function of plasma glucose level gave a substantially lower Kt of 0.6 +/- 2.0 mM, which was consistent with the previously reported millimolar Km of GLUT-1 in erythrocyte model systems. Previously reported and reanalyzed quantification provided consistent kinetic parameters. We conclude that cerebral glucose transport is most consistently described when using reversible Michaelis-Menten kinetics.     

Summary of the II International Symposium on Cytomegalovirus

Human cytomegalovirus (HCMV) is a highly species-specific DNA virus belonging to the Betaherpesvirinae subfamily of the herpesviridae family. Like other herpesviruses, primary infection with HCMV is followed by persistence of the virus in a latent form. The sites of latency are still largely undefined, but they probably include bone marrow progenitor cells and peripheral blood monocytes. From these sites, the virus can reactivate, resulting in renewed shedding of the virus, or, in immunocompromized persons, development of disease. Humans are the only reservoir of HCMV and transmission occurs by person-to-person contact. Infection with HCMV is common. In most developed countries, HCMV seroprevalence steadily increases after infancy and 10-20% of children are infected before puberty. In adults, the prevalence of antibodies ranges from 40 to 100%. Although HCMV has a world-wide distribution, infection with HCMV is more common in the developing countries and in areas of low socioeconomic conditions, which is predominantly related to the closeness of contacts within these populations. Except for a mononucleosis-like illness in some persons, infection with HCMV rarely causes disease in immunocompetent individuals. However, HCMV can cause severe morbidity and mortality in congenitally infected newborns and immunocompromized patients, most notably transplant-recipients and HIV-infected persons. This article provides a review of the information presented at the Second International Symposium on Cytomegalovirus organized and convened by The Macrae Group (New York City, NY) in Acapulco, Mexico on 24-28 April 1998. During this symposium, the state-of-the-art knowledge on diagnosis, treatment and prophylaxis of HCMV infections were discussed, and, based on this information, attempts to highlight the future directions in basic and clinical research areas that need to be stimulated to facilitate advancement in prevention and treatment of CMV disease.     

Synthesis and biological evaluation of certain new thiazolopyrimidines

A series of 5-methyl-3-phenyl thiazolo[5,4-e][1,2,4]triazolo[1,5-c] pyrimidin-2-thiones and 5-methyl-3-phenyl thiazolo[5,4-e]pyrimidino[3,4-b][1,2,4]triazin-2-thiones were prepared as potential antimicrobial and antitumor agents. Some of the tested compounds showed promising activity. The detailed synthesis, spectroscopic and biological data are reported.     

Kinetics of human erythrocyte acetylcholinesterase inhibition by a novel derivative of physostigmine: phenserine

The elastic properties of carotid arteries of spontaneously hypertensive rats (SHR) and normotensive controls (Wistar-Kyoto rats [WKY]) were examined in vivo, in situ, and in vitro. The changes of internal diameter were measured with a high-resolution A-mode echo-tracking device simultaneously with the intra-arterial pressure at the carotid. The internal diameter at mean arterial blood pressure (MBP) was substantially smaller in vitro than in vivo in SHR (-33.8%) and WKY (-48.3%). The arterial distensibility was lower in vitro in all arteries compared with in vivo conditions (SHR, -30.1%; WKY, -60.4%; at MBP) despite a reduced incremental elastic modulus in vitro (SHR, -56.9%; WKY, -45.1%; at MBP). However, the in vitro and in vivo measurements show consistent elastic behavior of the carotid arteries between both strains of rats. Carotid arteries from WKY were also examined in situ. Although no significant reduction in internal diameter could be observed in situ, distensibility was dramatically decreased (-87% at MBP). These results emphasize the importance of considering the original vascular geometry when determining elastic properties of arteries. We conclude that experimental conditions are likely to be a critical determinant for the assessment of the mechanical properties of conduit vessels.     

Diagnostic tools in the evaluation of patients with viral hepatitis undergoing liver transplantation

Familiarity with the diagnostic parameters of viral hepatitis is imperative in the liver transplantation arena. Chronic viral hepatitis B and C are among the most common categories of end-stage liver disease. The preoperative diagnosis, determination of recurrent infection, and the assessment of antiviral therapeutic efficacy are dependent on appropriate virological testing. Furthermore, liver transplant personnel are at a high risk for parenterally transmitted viral hepatitis infection. Knowledge and understanding of the serological patterns of acute and chronic viral hepatitis, as well as recognition of the immune status for one or more of these viruses, will facilitate prevention and treatment of viral hepatitis for these health care providers.