Retinoic acid receptor gamma1 expression determines retinoid sensitivity in pancreatic carcinoma cells

A highly enriched spindle pole preparation was prepared from budding yeast and fractionated by SDS gel electrophoresis. Forty-five of the gel bands that appeared enriched in this fraction were analyzed by high-mass accuracy matrix-assisted laser desorption/ ionization (MALDI) peptide mass mapping combined with sequence database searching. This identified twelve of the known spindle pole components and an additional eleven gene products that had not previously been localized to the spindle pole. Immunoelectron microscopy localized eight of these components to different parts of the spindle. One of the gene products, Ndc80p, shows homology to human HEC protein (Chen, Y., D.J. Riley, P-L. Chen, and W-H. Lee. 1997. Mol. Cell Biol. 17:6049-6056) and temperature-sensitive mutants show defects in chromosome segregation. This is the first report of the identification of the components of a large cellular organelle by MALDI peptide mapping alone.     

Sustained nitrite accumulation in a membrane‐assisted bioreactor (MBR) for the treatment of ammonium‐rich wastewater

A membrane‐assisted bioreactor (MBR) for sustained nitrite accumulation is presented, treating a synthetic wastewater with total ammonium nitrogen (TAN) concentrations of 1 kg N m^?3 at a hydraulic retention time down to 1 day. Complete biomass retention was obtained by microfiltration with submerged hollow fibre membranes. A membrane flux up to 189.5 dm³ day^?1 m^?2 could be maintained at a suction pressure below 100 kPa. Nitrification was effectively blocked at the nitrite stage (nitritation), and nitrate concentration was less than 29 g N m^?3. The rate of aeration was reduced to obtain a mixture of ammonium and nitrite, and after adjusting this rate the TAN/NO₂‐N ratio in the reactor effluent was kept around unity, making it suitable for further treatment by anaerobic oxidation of ammonium with nitrite. After increasing again the rate of aeration, complete nitrification to nitrate recovered after 11 days. It is suggested that nitrite accumulation resulted from a combination of factors. First, the dissolved oxygen (DO) concentration in the reactor was always limited with concentrations below 0.1 g DO m^?3, thereby limiting nitrification and preventing significant nitrate formation. The latter is attributed to the fact that ammonium‐oxidising bacteria cope better with low DO concentrations than nitrite oxidisers. Second, the MBR was operated at a high ammonia concentration of 7–54 g N m^?3, resulting in ammonia inhibition of the nitrite‐oxidising microorganisms. Third, a temperature of 35 °C was reported to yield a higher maximum growth rate for ammonium‐oxidising bacteria than for nitrite‐oxidising bacteria. Nitrite oxidisers were always present in the MBR but were out‐competed under the indicated process conditions, which is reflected in low concentrations of nitrate. Oxygen limitation was shown to be the most important factor to sustain nitrite accumulation. Nevertheless, nitritation was possible at ambient temperature (22–24 °C), lower ammonia concentration (<7 g N m^?3) and when using raw nitrogenous wastewater containing some biodegradable carbon. Overall, application of the MBR for nitritation was shown to be a reliable technology. © 2003 Society of Chemical Industry     

Enantioselectivity in capillary electrophoresis using the macrocyclic antibiotics

The macrocyclic antibiotics recently have been shown to exhibit powerful enantioselectivity towards numerous compounds. There are a number of ways that one can alter enantioselectivity in the macrocyclic antibiotic-based separation schemes. The macrocyclic antibiotics are enantioselective for positively-charged solutes using the ansamycins and enantioselective for anionic compounds using the glycopeptides. Within a given class of antibiotics such as the glycopeptides, enantioselectivity may also be altered by use of micelles, uncoated vs. coated capillaries, or manipulation of operating parameters such as pH or organic modifiers. In this work, we will examine the various ways to alter enantioselectivity in the macrocyclic-based separations.     

Outcome of hepatitis C patients with and without hepatocellular carcinoma undergoing liver transplant

OBJECTIVE: Hepatitis C virus (HCV) infection is associated with development of hepatocellular carcinoma (HCC). The aim of this study was to examine clinical characteristics and outcome of patients with HCV with or without HCC undergoing liver transplant. METHODS: We reviewed the charts of all 55 patients transplanted between November 1990 and December 1996 for HCV cirrhosis with HCC and compared them with a control group of HCV patients without HCC. Patients with a history of alcohol abuse or HBsAg positivity were excluded. There were 37 men and 18 women, with a mean age of 57.6 yr (range, 19-70 yr) in the HCC group. RESULTS: There was no significant difference between the HCC and nonHCC groups regarding Child's class or United Network for Organ Sharing (UNOS) status at the time of transplant. Twenty-six (45%) patients were diagnosed or suspected of having HCC before transplant. Twenty-five patients (45.5%) had a single focus of HCC. Fourteen percent (seven of 50) of the patients with HCC had been treated with interferon, whereas 12% (six of 52) of patients in the nonHCC group had received interferon. Duration of interferon therapy ranged from 1 to 9 months. All interferon treatment occurred within 5 yr of transplant. A history of intravenous drug use or transfusion was identified in 37 (67%) of HCC patients. Thirty-two patients (58%) without HCC had a parenteral exposure. There was no significant difference in patient or graft survival rates between the patients with and without HCC. CONCLUSION: Approximately one-half of HCC was not detected before liver transplant. There was no significant difference in the mode of transmission, clinical status at the time of transplant, or outcome between the HCV patients with and without HCC.     

Cocaine- and amphetamine-regulated transcript peptide immunohistochemical localization in the rat brain

The clinical features of Crohn's disease manifest during adolescence are varied as in adults. The potential complication of growth impairment and concomitant delay in pubertal development is unique to this population. Cytokines released from the inflamed bowel and chronic nutritional insufficiency are the major factors in the pathophysiology of growth inhibition. Hence reduction of intestinal inflammation and consistent provision of adequate nutrition are of paramount importance in management. Drug treatment mirrors that of adults; few specifically paediatric clinical trials have been conducted. Enteral nutrition is an important therapeutic alternative for young patients. There is evidence that it constitutes both a primary therapy of inflammation and a means of providing the calories needed for growth. In the setting of extensive disease, dependency on corticosteroids should be minimized through judicious administration of immunosuppressive drugs. For an adolescent with localized stenotic disease, optimal management includes a timely referral for intestinal resection as a means of providing an asymptomatic interval during which growth and pubertal development can normalize.     

Physical mechanisms for chemotactic pattern formation by bacteria

This paper formulates a theory for chemotactic pattern formation by the bacteria Escherichia coli in the presence of excreted attractant. In a chemotactically neutral background, through chemoattractant signaling, the bacteria organize into swarm rings and aggregates. The analysis invokes only those physical processes that are both justifiable by known biochemistry and necessary and sufficient for swarm ring migration and aggregate formation. Swarm rings migrate in the absence of an external chemoattractant gradient. The ring motion is caused by the depletion of a substrate that is necessary to produce attractant. Several scaling laws are proposed and are demonstrated to be consistent with experimental data. Aggregate formation corresponds to finite time singularities in which the bacterial density diverges at a point. Instabilities of swarm rings leading to aggregate formation occur via a mechanism similar to aggregate formation itself: when the mass density of the swarm ring exceeds a threshold, the ring collapses cylindrically and then destabilizes into aggregates. This sequence of events is demonstrated both in the theoretical model and in the experiments.     

Immunohistochemical localization of novel CART peptides in rat hypothalamus, pituitary and adrenal gland

CART peptide specific polyclonal antisera were raised in rabbits. The antisera were raised to CART peptide fragments that span most of the predicted CART protein. The specificity of each antisera was demonstrated by blockade of immunostaining by the immunizing peptide but not by the other CART peptide fragments. In the hypothalamus and pituitary of colchicine and noncolchicine treated rats, immunostaining was observed in cell bodies, fibers and varicosities. Clusters of cells were also stained in the adrenal medulla. It is noteworthy that cellular immunostaining was only found in areas previously shown to express CART mRNA. These findings indicate the presence of CART peptide(s) in the hypothalamus, pituitary, and adrenal gland. Furthermore, we also present evidence for the possible processing of the CART pro-peptide into smaller peptide fragments. These neuroanatomical findings suggest a role of CART peptides in hypothalamic, pituitary and adrenal function.     

Interactions between carotid sinus mechanoreceptor and chemoreceptor reflex loops

n-Alkane assimilating yeast, Candida tropicalis YO-148, was grown on an n-alkane-containing medium. A synthetic diet containing 6.8% of dried yeast was fed to rats. The fatty acid composition of adipose tissue and liver fats was determined after a two week feeding period. The percentage of odd-numbered acids increased in the animals fed the yeast diet. Furthermore, it was shown that heptadecenoic acid, the major odd-numbered acid in yeast, was accumulated in neutral lipid fraction of adipose tissue fat. Fatty acid composition of protein isolate prepared from yeast cells had a profile similar to that of the original cells.