Comparison of Behavioural Effects of Repeated Treatment with Methamphetamine plus Scopolamine and Methamphetamine Alone on Behavioural Sensitization and Conditioned Response

We investigated how repeated treatments with methamphetamine (4.0mgkg^?1, i.p.) plus scopolamine (0.5mgkg^?1, i.p.) and methamphetamine alone effected behavioural sensitization and conditioned response in rats. Repeated methamphetamine plus scopolamine treatment induced a more progressive and enduring enhancement of focused stereotyped behaviour than repeated methamphetamine treatment. Stereotyped behaviour induced by methamphetamine plus scopolamine was reproduced by challenge injections of methamphetamine plus scopolamine, methamphetamine, and to a lesser extent by scopolamine challenges. The methamphetamine plus scopolamine-sensitized rats were conditioned to a low frequency tone (300 Hz, 100 dB) associated with the drug state. They exhibited a conditioned response to pairings of the tone (conditioned stimulus) and placebo injections. However, they did not respond to the tone alone or the placebo injections alone. The methamphetamine-sensitized rats failed to demonstrate any conditioning; only the repeated methamphetamine plus scopolamine treatment induced sensitization to the drug-associated tone. Pairings of exteroceptive conditioned stimulus-interoceptive unconditioned stimulus associations may provide an important source for conditioning to the tone associated with the drug state. We conclude that behavioural sensitization may operate via a reciprocal balance between the dopaminergic and cholinergic inhibitory systems, in favour of a dopaminergic dominance. Conditioning to the drug-associated tone may be mediated via a reciprocal balance between the two transmitter systems.     

Increase of Peripheral Blood B Cells with Fc Receptor for IgA in Patients with IgA Nephropathy

A B-cell subset with Fc receptors for IgA (B alpha cells) has been observed in human peripheral blood. To investigate aberrations of B cells in a diseased state, the percentages of B alpha cells were enumerated in peripheral blood from patients with IgA nephropathy, which is characterized by preponderant deposition of IgA-dominant immune complexes in the glomerular mesangial area. The present study showed a significant increase in B alpha cells in peripheral blood from patients with IgA nephropathy but not in those with chronic proliferative glomerulonephritis without mesangial IgA deposition. Most Fc alpha R-bearing cells were observed in surface IgA bearing lymphocytes. No linear correlation was observed between the levels of serum IgA and the percentages of B alpha cells. The addition of aggregated IgA to cultures did not induce Fc alpha R-bearing B cells in vitro. It is postulated that B alpha cells might have some pathogenetic role in the development of IgA nephropathy and that some antigenic stimuli might play a role in the increase of peripheral blood B alpha cells in patients with IgA nephropathy.     

Isolation of α-fetoprotein Messenger RNA

Messenger RNA for α-fetoprotein (AFP mRNA) was isolated from mouse yolk sac by a combination of indirect immunoprecipitation of AFP-synthesizing polysomes and poly(U)-Sepharose affinity chromatography of poly(A)-containing mRNA. Over 200-fold purification was achieved. Purified AFP mRNA migrated as a single band at about 21S on agarose gels in the presence of 6 M urea. Upon translation in wheat germ extracts, 98% of the protein synthesized reacted with specific antibodies to AFP. The total translation product was characterized by means of gel electrophoresis under two different conditions and by tryptic peptide analysis. It was concluded that the AFP preparation was essentially free of other yolk sac mRNA and was able to direct the synthesis of authentic AFP.     

A case of Sweet''s syndrome following septic pulmonary emboli after high-dose chemotherapy for advanced testicular cancer

A 33-year-old man with advanced testicular cancer underwent high-dose chemotherapy combined with peripheral blood stem cell transplantation. After administration of granulocyte colony-stimulating factor (G-CSF), multiple infiltrative erythema was identified on the face, thigh, and lower leg. A dermatologist diagnosed this as Sweet's syndrome caused by G-CSF; consequently G-CSF administration was stopped. When the skin lesions had improved, phlebitis was found at the injection site of the peripheral vein catheter. The patient then suffered from sudden left chest pain and dyspnea. Chest computed tomography showed the characteristic findings of septic pulmonary emboli (SPE). He was treated by the administration of vancomycin, fluconazole, and pazufloxacin mesilate. Although Sweet's syndrome and SPE are rare diseases, the presence of these diseases must be considered when performing chemotherapy for urological malignancy.     

BK virus subtype 1 infection associated with tubulointerstitial nephritis in a renal allograft recipient

The BK polyomavirus (BKV) infects most of the human population, but clinically relevant infections are usually limited to individuals who are in an immunosuppressed state. The significance of BKV infection was investigated in a 50-year-old man who underwent cadaveric kidney transplantation and was treated with tacrolimus, mycophenolate mofetil and prednisolone. By staining renal biopsy specimens with a monoclonal antibody against BK large T antigen, we were able to observe the relationship between the appearance of the BKV antigen and the extent of immunosuppression in this patient. We also determined that BKV belonged to genotype I by analysis of viral DNA from the patient's urine.     

Effect of cholestasis induced by organic anion on the lipid composition of hepatic membrane subfractions and bile in rats

Several organic anions inhibit the secretion of cholesterol and phospholipid into bile without affecting total bile acid secretion (uncoupling). The uncoupling induced by sulphobromophthalein (BSP) alters the fatty acid composition of biliary lecithin. The purpose of this study was to investigate the relationship between the lipid composition of bile and of liver subcellular membrane fractions during BSP-induced uncoupling. After depletion of the bile salt pool, rats fitted with a bile duct cannulus were infused with sodium taurocholate given either alone or with BSP. Bile was collected and liver microsomes and canalicular membranes were isolated for analysis of lipid composition. In bile, uncoupling increased the cholesterol/phospholipid ratio (C/P ratio) and the saturated/unsaturated fatty acid ratio (S/U ratio) in phosphatidylcholine. The C/P ratio was increased in the canalicular membrane, but the membrane phosphatidylcholine S/U ratio decreased during uncoupling. In microsomes, the S/U ratio of membrane phosphatidylcholine was slightly increased, but the C/P ratio was unaffected during uncoupling. These results support the hypothesis that an increased secretion of hydrophobic phosphatidylcholine species from the canalicular membrane into bile reduces the proportion of hydrophobic phosphatidylcholine species in the canalicular membrane during uncoupling. The decreased contribution of hydrophobic phosphatidylcholine species may ameliorate the decrease in membrane fluidity resulting from the accumulation of cholesterol in the canalicular membrane and stimulate the synthesis of hydrophobic phosphatidylcholine species in the microsomes.