A family with a satellited Yq chromosome

Summary A large pedigree with a satellited Yq chromosome is described, Q, C, and NOR banding were performed. Family C proband suffers from a Klinefelter syndrome.     

Analytical strategies for therapeutic monitoring of drugs and metabolites in biological fluids : Plenary lecture

Therapeutic drug monitoring can involve quantitation in either microgram, nanogram or picogram concentrations present in a complex biological matrix (whole blood, urine or tissue).The chemical structure of a compound influences not only the analytical method best suited to its quantitation, but also its acid/base character (PK_a) and its extractability. The dose administered, the bioavailability of the dosage form, and the pharmacokinetic profile of the drug govern the circulating concentrations of either the parent drug and/or its metabolites present in vivo, and dictate the ultimate sensitivity and specificity required of the analytical method.The degree of sample preparation required is dependent on the analytical method used (gas—liquid chromatography, thin-layer chromatography, high-performance liquid chromatography) and on the tolerance of the specific type of detection system to contamination. Factors leading to compound losses during sample preparation (adsorption, stability) are critical at low concentrations and can adversely affect the reliability of an assay, therefore maximizing the overall recovery of the assay is essential not only for high sensitivity but also for good precision and accuracy. Therefore, the criteria to be used in sample preparation should aim to optimize all of the above factors in the overall development of a reliable and validated method for the compound suitable for use in clinical therapeutic monitoring.     

Living immobilized Acetobacter in Ca-alginate in vinegar production: Perliminary study on optimum conditions for immobilization

Summary The optimum conditions forAcetobacter immobilization were investigated. The results show that: 1) the maximum oxygen uptake rate (OURm) and cell release are related to alginate and cell concentration in the gel; 2)different alginate concentration does not affect cell viability, but long storage in CaCl₂ reduces the number of living cells; 3)the double alginate gel layers had no influence on cell viability and on the OURm and prevented cell leakage from the gel matrix.     

Trehalase activity and its regulation during growth of Saccharomyces cerevisiae.

Trehalase activity decreased in 95% at the onset of the transition phase of growth of S. cerevisiae. The question which we raised was whether this phenomenon was due to proteolysis or to conversion of the enzyme to a less active form (dephosphorylation). Immunological methods allowed to identify the presence of the trehalase protein during cell growth. At the same stage of growth, an increase in the non-phosphorylated enzyme was detected "in vitro". Results utilizing mutant strains also indicated that regulation occurred by interconversion of forms. The same mechanism also seems to control trehalase activity in non proliferating conditions.     

Influence of dilution rate and induction of cloned gene expression in continuous fermentations of recombinant yeast

The effects of growth rate on cloned gene product synthesis in recombinant Saccharomyces cerevisiae have been studied in continuous culture. The plasmid employed contains a yeast GAL10-CYC1 hybrid promoter directing expression of the E. coli lacZ gene. beta-Galactosidase production was therefore controlled by the yeast galactose regulatory circuit, and the induction process and its effects were studied at the various dilution rates. At all dilution rates plasmid stability decreased with induction of lacZ gene expression. In some instances, two induced "steady states" were observed, the first 10-15 residence times after induction and the second after 40-50 residence times. The second induced steady state was characterized by greater biomass concentration and lower beta-galactosidase specific activity relative to the first induced "steady-state." beta-Galactosidase specific activity and biomass concentration increased as dilution rate was reduced, and despite lower flow rate and plasmid stability, overall productivity (activity/L/hr) was substantially higher at low dilution rate. Important factors influencing all of the trends were the glucose and galactose (inducer) concentrations in the vessel and inducer metabolism.     

Role of tissue hypoxia as the mechanism of lactic acidosis during E. coli endotoxemia.

We compared the hemodynamic and metabolic alterations produced in rabbits by similar decreases in cardiac output created by inflating a balloon placed in the right ventricle (n = 6) with those produced by an intravenous bolus of Escherichia coli lipopolysaccharide (LPS; SEP group; n = 6). We measured O2 consumption (VO2), O2 transport (TO2), and O2 extraction ratio (ERO2) for the whole animal and also for the left hindlimb. Both groups experienced similar decreases in cardiac output, systemic TO2, and VO2 and similar increases in ERO2. For the hindlimb, TO2 was similar, but VO2 and ERO2 were lower for the SEP group 30 min after LPS administration (P less than 0.05); however, this difference disappeared during the remainder of the experiment. Arterial lactate concentration was greater (P less than 0.05) for the SEP group. There were no differences in skeletal muscle PO2, measured with a multiwire surface electrode, or in cardiac and skeletal muscle concentrations of high-energy phosphates. We hypothesize that a direct effect of LPS on cellular metabolism may have resulted in greater arterial lactate concentration for the SEP group.     

The Roberts syndrome

Summary Four siblings with the autosomal recessive Roberts syndrome are reported, and we discuss the phenotypic overlap of this syndrome with other similar radial, aplasia syndromes.     

Liver transplantation in a patient with cholangiocarcinoma and ulcerative colitis.

A 39 year-old patient with cholangiocarcinoma and pre-existing ulcerative colitis was successfully treated by orthotopic liver transplantation. He was given low doses of prednisone and azathioprine and survived for more than 9 months, dying with tumour metastases, thrombosis of the inferior vena cava and an intra-abdominal abscess. At autopsy the homograft showed little evidence of rejection. Preoperatively the patient had septicemia. Removal of his liver was difficult. The discrepancy between donor and recipient in size of blood vessels and the presence of two hepatic arteries in the donor caused problems during the vascular anastomoses. During the operation cardiac arrest occurred. Postoperatively there were several medical and surgical problems, including intraperitoneal and gastrointestinal hemorrhage, paralysis of the right dome of the diaphragm, sinus bradycardia, massive diuresis, peroneal nerve palsy, and one major and three minor episodes of rejection, which were reversed by giving pulse doses of methylprednisolone intravenously.