Out-of-Plane Negative Magnetoresistance of Bi2Sr1.6La0.4CuO6+δ Single Crystals in the Underdoped Region

In order to investigate a relationship between the carrier concentration and negative magnetoresistance in the underdoped region, we have performed out-of-plane electrical resistivity measurements for underdoped Bi ₂ Sr _1.6 La _0.4 CuO ₆₊ single crystals. Giant negative magnetoresistance has been observed in the most abundant carrier sample with = 0.12 in our experiment. The negative magnetoresistance reduces with decreasing carrier concentration.     

Steroid hormones and their receptors in the brain

Steroid hormones regulate several important functions of the brain by altering the expression of particular genes through their receptors. First in this paper the localization of glucocorticoid receptor immunoreactivity and mRNA in the brain was examined. Second biphasic effects of glucocorticoid on the hippocampus was described and particular emphasis was given on the apoptosis. Third the significance of estrogen receptor in the sexually dimorphic areas was discussed. These results suggest that steroids modulate the gene expression along with the alteration of cell structures in a different manner in a tissue-specific pattern.     

Identification of the region of alpha-catenin that plays an essential role in cadherin-mediated cell adhesion

alpha-Catenin is an intrinsic component of the cadherin adhesion complex and is a 102-kDa protein with multiple interaction sites, including homodimerization sites, and binding sites for beta- and gamma-catenin (plakoglobin), alpha-actinin, and actin. Besides the binding to beta- or gamma-catenin, it is unknown, however, which interaction is critical for the function of cadherins. By expressing a series of E-cadherin-alpha-catenin chimeric molecules on leukemia cells (K562), we have identified the region of alpha-catenin that confers aggregation inducing activity to nonfunctional tail-less E-cadherin. The region has been mapped to the carboxyl-terminal 295 amino acids of alpha-catenin. Consistent with this result, expression in alpha-catenin-deficient cells (DLD-1/Delta alpha) of a mutant alpha-catenin molecule consisting of the amino-terminal beta-/gamma-catenin-binding site and the carboxyl-terminal cell adhesion region identified in the above experiments induced E-cadherin-mediated cell aggregation and compaction. Cells expressing E-cadherin chimeric molecules with the homologous carboxyl-terminal region of vinculin, which contains the actin-binding site of vinculin, did not, however, aggregate as strongly as ones expressing E-cadherin-alpha-catenin chimeric molecules.     

Experimental glaucoma model in the rat induced by laser trabecular photocoagulation after an intracameral injection of India ink

A combined hemostatic defect consisting of a reduction in certain procoagulants, anticoagulants (antithrombin III-ATIII-, protein C-PC-) and components of the fibrinolytic system (plasminogen-Plg-) was demonstrated in very-low-birth-weight infants (VLBW <1,500 g) with gestational age 26-32 weeks. Sixteen of them were healthy, 28 were suffering from RDS and 24 from septicemia. The hemostatic defect was more profound in the RDS group, nevertheless increased TAT (thrombin + ATIII complex) and/or PAP values (plasmin + a2-antiplasmin complex) was a more frequent finding in the septicemic group of infants (91.8 vs. 17.9%). Moderate-to-severe thrombocytopenia was detected in a higher percentage in the septicemic (70.8%) than in the RDS group (50%), and increased D-dimers were demonstrated in 34.8 and 28.6% of the infants, respectively. Elevated TAT or PAP values were not always associated with gross coagulation abnormalities, and advanced disseminated intravascular coagulation (DIC) was only documented in 16.7% of the septicemic and 7.1% of the RDS infants. None of the VLBW neonates presented with clinical evidence of thrombosis, although hemorrhagic manifestations were apparent in 34.8 and 14.3% of the neonates with septicemia or RDS, respectively, mainly due to DIC or severe thrombocytopenia. In conclusion, increased TAT and/or PAP values are good indicators of the in vivo activation of the hemostatic system, but still their impact on sick neonates morbidity and mortality remains unknown.     

Efficacy of early plasmapheresis in Bickerstaff's encephalitis

Double filtration plasmapheresis (DFPP) was performed in a patient with Bickerstaff's brainstem encephalitis (BBE) in its early phase. He was a 27-year-old male patient suffering from diplopia, facial palsy and drowsiness following upper respiratory tract infection, and had high titers of immunoglobulin G (IgG) antibodies against ganglioside NeuAc(alpha)2-8NeuAc(alpha)2-3Gal(beta)1-3GalNAc(beta)1-4(NeuAc(al pha)2-8NeuAc(alpha)2-3)Gal(beta)1-4Glc(beta)1-1'Cer (GQ1b) in the serum. DFPP effected immediate improvement of his drowsiness, supporting the diagnosis of BBE. Our observations suggest that DFPP during the early phase of BBE efficiently prevents the progression of consciousness disturbances.