Case of the month: April 1998--30 year old male with perineal numbness

A 30-year-old male presented with a 2 year progressive course of bowel and bladder dysfunction, mild leg weakness and sensory abnormalities in sacral dermatomes. MRI showed an intra-axial conus medullaris lesion which was excised and identified as a ganglioglioma. The case presents the typical clinical course and histopathology of this unusual lesion which carries a favorable prognosis after gross total removal. Preoperative neurological function in such patients is highly predictive of post-operative outcome.     

Repression of c-fos and c-jun gene expression is not part of AT2 receptor coupled signal transduction

Recent world-wide publications were reviewed in order to determine the clinical characteristics and therapeutic relevance of the chlamydial respiratory tract infections in humans. It was emphasized that Chlamydia pneumoniae could initiate asthma and may be associated with acute asthma exacerbation. Laboratory procedures for identifying chlamydia and difficulties concerned with the diagnostics of this intracellular pathogen were also presented. In patients with evidence of chlamydial infection the casual treatment (macrolides, tetracyclines, fluoroquinolones) may induce major improvement or complete resolution of asthma.     

A controlled evaluation of a lifts and transfer educational program for nurses

The role of the parasympathetic autonomic nervous system (ANS) in digoxin intoxication was investigated in atropine pretreated conscious rabbits. Both the electrocardiographic registration and the histologic analysis indicated possible prevention of lethal arrhythmias by atropine pretreatment. The hearts of animals pretreated with atropine appeared less damaged, since they presented only a light cytoplasmic vacuolization. It was evident that the administration of digoxin without atropine pretreatment provoked dramatic signs of digitalis intoxication followed by animal death. Myocardia of these rabbits were highly damaged. On the other hand, our experimental data indicated that the abolishment of the vagal tone by atropine blockade caused only signs (i.e. inversion of the T wave) due to myocardial ischemia, to which the light cytoplasmic vacuolation could be correlated. Myocardial ischemia could be caused by constriction of coronary blood vessels, which could be consequential to both the prevalent activity of the orthosympathetic ANS, following parasympathetic blockade, and direct digoxin effects on vascular fibrecells, which both produce vasoconstriction. Therefore, it is reasonable to assume that the parasympathetic ANS plays a major role in digitalis intoxication in rabbits.     

Inherited retinal degeneration: exceptional genetic and clinical heterogeneity

The function of the retina is to detect light and to send appropriate signals to the brain in response. Inherited diseases that cause the retina to degenerate, leading to either partial or total blindness, affect approximately 1 in 3000 people. Rapid progress is being made in identifying the genetic causes of common, inherited retinal diseases, such as retinitis pigmentosa and macular degeneration, as well as some of the rare forms of retinal disease. Linkage studies of large families and candidate-gene screening of known retinal genes have already identified 59 independent genetic loci that can cause retinal degeneration. The astounding genetic and clinical heterogeneity that is being revealed is a 'nightmare' for those interested in molecular diagnostics but, at the same time, provides great insight into functional aspects of the normal retina.     

Equilibrium binding studies of non-claret disjunctional protein (Ncd) reveal cooperative interactions between the motor domains

Non-claret disjunctional protein (Ncd) is a minus end-directed microtubule motor required for normal spindle assembly and integrity during Drosophila oogenesis. We have pursued equilibrium binding experiments to examine the affinity of Ncd for microtubules in the presence of the ATP nonhydrolyzable analog 5'-adenylyl-beta, gamma-imidodiphosphate (AMP-PNP), ADP, or ADP + Pi using both dimeric (MC1) and monomeric (MC6) Ncd constructs expressed in Escherichia coli. Both MC1 and MC6 sediment with microtubules in the absence of added nucleotide as well as in the presence of either ADP or AMP-PNP. Yet, in the presence of ADP + Pi, there is a decrease in the affinity of both MC1 and MC6 for microtubules. The data for dimeric MC1 show that release of the dimer to the supernatant is sigmoidal with the apparent Kd(Pi) for the two phosphate sites at 23.3 and 1.9 mM, respectively. The results indicate that binding at the first phosphate site enhances binding at the second site, thus cooperatively stimulating release. Stopped-flow kinetics indicate that MgATP promotes dissociation of the Mt.MC1 complex at 14 s-1, yet AMP-PNP has no effect on the Mt.MC1 complex. These results are consistent with a model for the ATPase cycle in which ATP hydrolysis occurs on the microtubule followed by detachment as the Ncd.ADP.Pi intermediate.     

Current concepts and controversies in IgA nephropathy

A randomized, open trial involving 260 Tanzanian children, aged 1-5 years, with acute Plasmodium falciparum malaria was conducted to evaluate the efficacy of the combination antimalarial CGP 56697 (artemether and benflumetol), and to compare it with chloroquine, the standard drug used for malaria treatment in the Kilombero area. Children who had received rescue medication within the first 48 h or had a negative slide at the same time were excluded. Seven-day parasitological cure rates were 94% (95% CI 88-97.5) for CGP 56697 and 35.4% (95% CI 25.9-45.8) for chloroquine. Using the same definition, the 14-day parasitological cure rates were 86.4% (95% CI 78.5-92.2) for CGP 56697 and 10.3% (95% CI 5.1-18.1) for chloroquine. Gametocytes were more effectively suppressed by CGP 56697 than by chloroquine. There were no major adverse events with either drug. CGP 56697 is highly efficacious against P. falciparum in this area of Tanzania. The study contributes to the discussion on treatment strategies, particularly whether chloroquine may still fulfil its role as first-line drug in an area of high malaria transmission and very high levels of chloroquine resistance.     

Effect of butylated hydroxyanisole on catalase activity and malondialdehyde content in aging Zaprionus paravittiger (diptera)

Catalase activity and malondialdehyde (MDA) content were measured in whole body and mitochondrial homogenates of the banana fruit fly, Zaprionus paravittiger, fed on control and butylated hydroxyanisole (BHA, 10 mM) mixed diets. Catalase activity increased during the reproductive period and decreased thereafter with age. However, the MDA content increased with advancing age in both sexes. In general, females exhibited higher catalase activity and lower MDA content as compared to their male counterparts. BHA feeding increased catalase activity significantly during all age intervals in both sexes. Mitochondrial fractions had lower catalase activity and lower MDA content than whole body homogenates. However, the pattern of changes was similar in both homogenates with age as well as on antioxidant feeding. These results suggest that BHA strengthens the defense mechanism of the insects by increasing catalase activity and reducing MDA content which may be responsible for increased longevity of insects.