Minocycline induced autoimmune hepatitis and systemic lupus erythematosus-like syndrome.

Monocycline is the most widely prescribed systemic antibiotic for acne largely because it needs to be given only once or twice a day and seems not to induce resistance. Up to April 1994 11 cases of minocycline induced systemic lupus erythematosus and 16 cases of hepatitis had been reported to the Committee on Safety of Medicines. An analysis of these cases together with seven other cases shows the severity of some of these reactions. Two patients died while taking the drug for acne and a further patient needed a liver transplant. Acne itself can induce arthritis and is often seen in association with autoimmine liver disease, but the clinical and biochemical resolution seen after withdrawal of the drug, despite deterioration of the acne, suggests a drug reaction. In five cases re-exposure led to recurrence. Because reactions may be severe early recognition is important to aid recovery and also to avoid invasive investigations and treatments such as corticosteroids and immunosuppresants. Safer alternatives should be considered for treating acne.     

Influence of carbon and nitrogen sources on glutathione catabolic enzymes inCandida albicans during dimorphism

The effect of carbon sources, glucose and sucrose, and nitrogen sources such as ammonia, glutamate andl-citrulline on the activities of glutathione metabolic enzymes has been studied. Yeast and mycelial cells were used to identify changes in activity levels of glutathione reductase (GSSGR), glutathione transferase (GST), glutathione peroxidase (GPX) and -glutamyl transpeptidase (GGT). Enzyme activities from cells grown in sucrose media were lower than in glucose media regardless of the enzyme tested, morphological form, or the growth interval. In all enzymes except GST, activity was higher in yeast form than in mycelia, regardless of nitrogen source, with lower activity from 24 to 72 h than at 96 h. In citrulline media, yeast form showed the maximum GST, GGT, and GPX activity. In ammonia-amended media, mycelia showed maximum activity in GGT, whereas in glutamate media, mycelia showed the maximum activity in GST. Also, the type of nitrogen source had no effect on GPX activity in the mycelial form. Finally, changing the nitrogen source showed no significant effect on GSSGR activity, either in the yeast or mycelial form.     

Biological activities of lipopolysaccharides from Pectinatus cerevisiophilus

Abstract A procedure is described in which the protein crystals produced by Bacillus thuringiensis var. israelensis were solubilized in 50 mM NaOH with 10 mM EDTA at pH 11.7. This solubilization procedure gave protein gel profiles identical with those for intact crystals while maintaining full biological activity in the form of erythrocyte lysis capability. Crystals with and without protease activity were equally toxic to Aedes aegypti larvae.     

Spin-label studies of membrane-associated denatured hemoglobin in normal and sickle cells

A maleimide spin label (N-(1-oxyl-2,2,5,5-tetramethylpyrrolidinyl)-maleimide) was reacted with oxyhemoglobin-free cell stromata of normal and sickle cells. The EPR spectrum of spin-labeled red cell membranes showed that the spin labels are attached to at least two different binding sites. There was a major signal, A, which characterized a strongly immobilized environment and a minor signal, B, which characterized a weakly immobilized environment. Quantitative EPR measurements using equal amounts of Hb AA and Hb SS red blood cells demonstrated that Hb SS red cell membranes had an approximately four times higher EPR signal intensity than Hb AA red cell membranes ((7.98 ± 1.14) · 10⁵ and (2.2 ± 1.2) · 10⁵ spin labels/cell, respectively). Moreover, the ratio of signal intensities A and B are different in these cells. Comparative spectrophotometric studies of membrane-associated denatured hemoglobins of Hb AA and Hb SS red cell membranes suggested that the EPR signal A is derived from spin labels attached to membrane-associated denatured hemoglobin, while signal B is mainly from spin labels attached to membrane-associated denatured hemoglobin, while signal B is mainly from spin labels attached to membranes. The combination of EPR spectrum of Hb AA membranes pretreated with N-ethyl-maleimide and that of spin-labeled precipitated hemoglobin further strengthened this conclusion.     

The increase in activity of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase in skeletal muscles of rats after subcutaneous administration of N,N′-dimethyl-para-phenylenediamine

Summary After subcutaneous administration of N,N-dimethyl-para-phenylenediamine (DPPD) in rats, a myogenic myopathy was produced in the skeletal muscles. In this communication, the results of the application of various histochemical techniques for the localization of oxidoreductases, transferases, hydrolases and isomerases and biochemical techniques for the estimation of activities of oxidoreductases in the experimental skeletal muscles are presented. The most striking result was the activity of glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase which increased dramatically during the early phase of the muscle disease. The increase in activity of the pentose phosphate shunt enzymes was the first pathological alteration and was present as early as 8 h after a single injection of DPPD. Histochemical techniques for demonstration of activity of both enzymes are therefore highly suited for the detection of minor diseases and the early onset of major diseases of the neuromuscular system. Some glycolytic enzymes as well as some enzymes of the aerobic part of the metabolism showed an early decrease or increase in activity indicating a metabolic imbalance in the muscle fibres. There were more fibres with an intermediate pattern of the energy yielding enzymes in the experimental muscle specimens then in specimens from the control groups. The activity of the catabolic hydrolytic enzymes was strongly increased in pathological muscles. The aerobic muscles were more vulnerable to DPPD than the anaerobic muscles.     

Alpha-ketoglutarate supply for amino Acid synthesis in higher plant chloroplasts: intrachloroplastic localization of NADP-specific isocitrate dehydrogenase

Isocitrate dehydrogenase was found in Pisum sativum chloroplasts purified on sucrose density gradients. A chloroplast-enriched pellet obtained by differential centrifugation formed two chlorophyll-containing bands. The lower one containing intact chloroplasts had NADP-specific isocitrate dehydrogenase and triose-phosphate isomerase activities. Mitochondria and peroxisomes were observed to band well away from the intact chloroplast region, as indicated by peak activities of fumarase and catalase, respectively. The presence of isocitrate dehydrogenase in chloroplasts suggests that chloroplasts may generate at least some of the α-ketoglutarate required for glutamate synthesis.     

Purification, characterization, and biological effects of a second bacteriocin from Enterococcus faecalis ssp. liquefaciens S-48 and its mutant strain B-48-28.

Enterococcus faecalis ssp. liquefaciens S-48 (producer of the peptide antibiotic AS-48) and its mutant B-48-28 (AS-48-) secrete the bacteriocin Bc-48. This substance has been purified to homogeneity from culture supernatants of strain B-48-28; it consists of a protein (80 kDa) stable from pH. 5.5 to 9.0 and sensitive to temperatures above 45 degrees C and to proteases. Its inhibitory spectrum is restricted to strains of Enterococcus faecalis. Bc-48 inhibits protein synthesis but does not affect amino acid uptake. A partial reduction of cell viability, together with autolysis, is also observed. Bc-48 differs from peptide AS-48 in both its molecular properties and mode of action.     

Pseudomeningocele: an unusual complication of craniofacial surgery.

A previously unreported complication of pseudomeningocele following monoblock frontofacial advancement is described. The defect was repaired by means of an extracranial approach with a satisfactory outcome.     

Genetic stability of the antagonistic character ofEnterococcus faecalis ssp.liquefaciens and the detection of a new inhibitory bacteriocin-like substance

The inhibitory capacity of strain S-48 ofEnterococcus faecalis ssp.liquefaciens was studied. The strain produces a broad-spectrum peptide antibiotic (AS-48) that has been characterized elsewhere. The isolation of mutants from S-48 after mutagenic treatment revealed another inhibitory substance which remained masked in the wild strain. The protein nature and restricted spectrum of this substance points to its being a bacteriocin (Bc-48).