Role of nucleotide pyrophosphatase in enflurane-induced reduction of UDP-glucuronic acid concentration in mouse liver

Because hepatic UDP-glucuronic acid levels decrease upon exposure to volatile anesthetics, the present study was designed to determine the mechanism by which enflurane decreases UDP-glucuronic acid in mice by measuring the concentrations of intermediates and the activities of enzymes in the UDP-glucuronic acid pathway. UDP-glucuronic acid concentrations were decreased by 40% in both male and female mice after 10 min of enflurane-induced narcosis. Concentration of UDP-glucose and the activities of diethylstilbestrol UDP-glucuronosyltransferase and UDP-glucose dehydrogenase were not affected by enflurane treatment. In contrast, nucleotide pyrophophatase activity was increased approximately 50% in both sexes. Thus, the decrease in hepatic UDP-glucuronic acid upon exposure of mice to enflurane is probably due to increased degradation by nucleotide pyrophosphatase.     

Protection from pathogenic SIV challenge using multigenic DNA vaccines

To assess DNA immunization as a strategy for protecting against HIV infection in humans, we utilized SIVmne infection of Macaca fascicularis as a vaccine challenge model with moderate pathogenic potential. We compared the efficacy of DNA immunization alone and in combination with subunit protein boosts. All of the structural and regulatory genes of SIVmne clone 8 were cloned into mammalian expression vectors under the control of the CMV IE-1 promoter. Eight M. fascicularis were immunized twice with 3 mg of plasmid DNA divided between two sites; intramuscular and intradermal. Four primed macaques received a further two DNA immunizations at weeks 16-36, while the second group of four were boosted with 250 microg recombinant gp160 plus 250 microg recombinant Gag-Pol particles formulated in MF-59 adjuvant. Half of the controls received four immunizations of vector DNA; half received two vector DNA and two adjuvant immunizations. As expected, humoral immune responses were stronger in the macaques receiving subunit boosts, but responses were sustained in both groups. Significant neutralizing antibody titers to SIVmne were detected in one of the subunit-boosted animals and in none of the DNA-only animals prior to challenge. T-cell proliferative responses to gp160 and to Gag were detected in all immunized animals after three immunizations, and these responses increased after four immunizations. Cytokine profiles in PHA-stimulated PBMC taken on the day of challenge showed trends toward Thl responses in 2/4 macaques in the DNA vaccinated group and in 1/4 of the DNA plus subunit vaccinated macaques; Th2 responses in 3/4 DNA plus subunit-immunized macaques; and Th0 responses in 4/4 controls. In bulk CTL culture, SIV specific lysis was low or undetectable, even after four immunizations. However, stable SIV Gag-Pol- and env-specific T-cell clones (CD3+ CD8+) were isolated after only two DNA immunizations, and Gag-Pol- and Nef-specific CTL lines were isolated on the day of challenge. All animals were challenged at week 38 with SIVmne uncloned stock by the intrarectal route. Based on antibody anamnestic responses (western, ELISA, and neutralizing antibodies) and virus detection methods (co-culture of PBMC and LNMC, nested set PCR- of DNA from PBMC and LNMC, and plasma QC-PCR), there were major differences between the groups in the challenge outcome. Surprisingly, sustained low virus loads were observed only in the DNA group, suggesting that four immunizations with DNA only elicited more effective immune responses than two DNA primes combined with two protein boosts. Multigenic DNA vaccines such as these, bearing all structural and regulatory genes, show significant promise and may be a safe alternative to live-attenuated vaccines.     

Sarcolemmal Na+-K+-ATPase activity in diabetic rat heart

Heart sarcolemmal membranes were isolated by the hypotonic shock-LiBr treatment from rats with chronic diabetes induced by a streptozotocin (65 mg/kg, iv) injection. Sarcolemmal Mg2+-dependent ATPase activity was elevated, whereas 5'-nucleotidase and K+-p-nitrophenylphosphatase activities in diabetic heart were depressed in comparison to control preparations. Although patent Na+-K+-ATPase and patent ouabain-sensitive Na+-K+-ATPase activities were unaltered, latent Na+-K+-ATPase activities, as determined in membranes after alamethicin or deoxycholate treatments, were found to be significantly depressed in diabetic animals. A depression in the latent Na+-K+-ATPase activity in diabetic preparations was also observed in membranes prepared by the sucrose density gradient method. Insulin-treated diabetic rats were observed to have normalized latent Na+-K+-ATPase activities. Total phospholipid content did not differ, but cholesterol content of the sarcolemmal membranes was significantly increased in diabetic heart preparations. Sarcolemmal Na+-K+-ATPase activity in diabetic heart was more resistant to treatments with filipin, an agent known to bind with cholesterol residues. These results suggest that chronic experimental diabetes is associated with some defects in sarcolemmal enzymatic activities and composition.     

Diarrhea Associated with Vibrio fluvialis in the United States

We report the isolation in the United States of Vibrio fluvialis from the stools of a patient who had severe watery diarrhea without fever and who subsequently died. V. fluvialis, a known enteric pathogen in other parts of the world, should be suspected in patients with watery diarrhea, especially in coastal areas.     

Increased elastin production in experimental granulomatous lung disease.

In the normal, healthy lung, elastin production is restricted to periods of development and growth. However, elastin expression in the adult lung has been observed in some forms of pulmonary injury, including pulmonary fibrosis. Here, we report that elastin production is significantly increased within precise interstitial compartments of the lung in an experimental model of granulomatous lung disease. An increase in the number and volume of elastic fibers within the alveolar walls was apparent on histological examination of Verhoeff-van Gieson-stained sections of silicotic rat lungs. Quantitation of mature elastin cross-links indicated that silicosis was accompanied by a 17-fold increase in lung elastin content when compared with values from saline-treated controls. In situ hybridization for tropoelastin mRNA revealed that elastin production was absent from granulomatous lesions yet was prominent at nonfibrotic alveolar septal tips, where a high density of elastic fibers is seen in the normal lung. Immunohistochemistry indicated tropoelastin was being expressed by alpha-smooth muscle actin-containing cells. Transforming growth factor-beta was immunolocalized to granulomatous regions of the silicotic lung but was absent from regions showing increased tropoelastin expression. These data indicate that the reinitiation of tropoelastin gene expression is associated with granulomatous lung disease, and this expression leads to the aberrant accumulation of mature elastin in the lung.     

Client choice of treatment and client outcomes

Participants in this study suffered from severe mental illness and were homeless at baseline. They were given their choice of five different treatment programs. The current study investigated two major questions: (1) what is the impact of positive expectancies about the efficacy of the chosen program on number of contacts with the chosen program and client outcomes; and (2) what is the impact of positive views about nonchosen programs (alternative choice variables) on contact with the chosen program and client outcomes. Client outcomes assessed were psychotic symptoms, days homeless, and client satisfaction. Positive expectancy variables were the number of reasons for choosing a program and confidence that the program would help. Alternative choice variables were the number of nonchosen programs visited and the attractiveness of a nonchosen program. Only the number of reasons for choosing the program was significantly related to program contact with the chosen program. Both of the positive expectancy variables and program contact were significantly correlated with consumer satisfaction. In general, neither the positive expectancy variables nor the alternative choice variables predicted changes in psychotic symptoms nor days homeless. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 339–348, 2003.     

Efficiency of human rotavirus propagation in cell culture.

This study was designed to find methods to reproducibly propagate human rotaviruses from fecal specimens and to determine the relationship between particle numbers and infectivity. Growth of virus was initially compared in primary and continuous lines of monkey kidney cells. Primary cells (African green and cynomolgus monkey kidney) supported virus growth directly from fecal specimens much more efficiently than did continuous lines of African green (CV-1) or rhesus (MA104) monkey kidney cells. Rotaviruses were grown in primary cells from 14 of 14 fecal specimens of different individuals collected over a 3-year period. Although rotaviruses in fecal samples could not always be grown in the continuous cell lines, two passages in primary cells appeared to fully adapt the viruses for propagation in the continuous cell line tested (MA104). The efficiency of rotavirus growth was quantified with five of the fecal isolates. It was calculated that, on the average, 1 out of every 46,000 particles in fecal specimens infected monkey kidney cells. After three passages in primary cells, an average of 1 out of every 6,600 progeny virus particles appeared to be infectious. Thus, rotaviruses in fecal specimens were consistently grown in primary cells, and passage in these cells both increased virus infectivity and adapted the viruses for growth in continuous cell lines.