A neurochemical study of rat brain maldevelopment induced by MAM treatment at different stages of gestation

The regional levels of several cell marker proteins in the brain and the ability of operant discrimination learning on a multiple fixed ratio (FR), fixed interval (FI) schedule were determined in rats with microencephaly induced by prenatal treatment with methylazoxymethanol (MAM), an antimitotic agent, on the 11 th to 13 th days (Group A) or on the 15 th day (Group B) of gestation. The cell marker proteins were determined with a sensitive enzyme immunoassay. Neuron-specific enolase (NSE; gamma gamma-enolase) had a significantly lowered level in the neocortex anterior in Group A. Non-neuronal enolase (NNE; alpha alpha-enolase) was significantly reduced in the superior colliculus, lateral geniculate body and optic nerve, but increased 1.5 fold in the retina in Group A. S-100b protein, a marker of astroglial cells, showed no significant change. As for the learning performance, the Group B animals showed an elevated behavioral activity and made evident discrimination between the FI and FR schedule. But Group A animals had prolonged FR components requiring responses to light on, and their spontaneous activity counts recorded by Automex showed an inhibition of behavior in light environments. These findings suggest a causative role of some developmental abnormality in the central visual system, indicated by the aberrant cell marker levels, in the disturbed learning ability of the Group A animals.     

Genetic variations at urotensin II and urotensin II receptor genes and risk of type 2 diabetes mellitus in Japanese

Urotensin II is among the most potent vasoactive hormones known and the urotensin II (UTS2) gene is localized to 1p36-p32, one of the regions reported to show possible linkage with type 2 diabetes in Japanese. When we surveyed genetic polymorphisms in the UTS2 and urotensin II receptor (GPR14) gene, we identified two SNPs with amino acid substitutions (designated T21M and S89N and an SNP in the promotor region (-605G>A) of the UTS2 gene, and two SNPs in the non-coding region of the GPR14 gene. We then studied these three SNPs in the UTS2 gene and two SNPs in the GPR14 gene in 152 Japanese subjects with type 2 diabetes mellitus and two control Japanese populations. The allele frequency of 89N was significantly higher in type 2 diabetic patients than in both elderly normal subjects (P = 0.0018) and subjects with normal glucose tolerance (P = 0.0011), whereas the allele frequency of T21M and -605G>A in the UTS2 gene and those of two SNPs in the GPR14 gene were essentially identical in these three groups. Furthermore, in the subjects with normal glucose tolerance, 89N was associated with significantly higher insulin levels on oral glucose tolerance test, suggesting reduced insulin sensitivity in subjects with 89N. These results strongly suggest that subjects with S89N in the UTS2 gene are more insulin-resistant and thus more susceptible to type 2 diabetes mellitus development.     

Establishment of gene transfer systems for and construction of the genetic map of a marine Vibrio strain.

Two gene transfer systems were established for a marine bacterium, Vibrio sp. strain 60. One was generalized transduction with a newly isolated bacteriophage, As3, and the other was conjugal gene transfer by the use of newly constructed transposon-facilitated recombination (Tfr) donors. As3 transduced various chromosomal markers at frequencies of 10(-4) to 10(-6). Tfr donors, which were constructed by introducing transposon Tn10 into both plasmid RP4 and the chromosome, mediated the polarized transfer of chromosomal genes from the sites of Tn10 insertion on the chromosome. By means of these gene transfer systems, a genetic map of the vibrio chromosome was constructed.     

Cytologic features of chordoid meningioma. A case report

BACKGROUND: Chordoid meningioma is a rare subtype of meningioma characterized by myxoid matrices deposited among epithelioid or vacuolated tumor cells and infiltrates of inflammatory cells, and its cytologic features have rarely been reported. CASE: A 57-year-old man with a history of headache and visual disturbance presented with a tumor in the suprasellar region. Intraoperative touch smear cytology of the tumor disclosed a cord-like arrangement of polygonal tumor cells occasionally containing intranuclear inclusions. Furthermore, periodic acid-Schiff-positive, mucinous matrices were deposited among the tumor cells. Also, infiltrates of lymphocytes and plasma cells were noted. Histologic, immunohistochemical and ultrastructural examination confirmed the diagnosis of chordoid meningioma. CONCLUSION: Intraoperative smear cytology in a case of chordoid meningioma showed distinctive cytologic features suggestive of the histologic patterns. The cytologic features, together with a histologic examination, are useful for its diagnosis.     

Increased number of Arginine-based salt bridges contributes to the thermotolerance of thermotolerant acetic acid bacteria, Acetobacter tropicalis SKU1100

Thermotolerant acetic acid bacteria (AAB), Acetobacter tropicalis SKU1100, can grow above 40 °C. To investigate the basis of its thermotolerance, we compared the genome of A. tropicalis SKU1100 with that of mesophilic AAB strain Acetobacter pasteurianus IFO3283-01. The comparative genomic study showed that amino acid substitutions from large to small residue and Lys to Arg occur in many orthologous genes. Furthermore, comparative modeling study was carried out with the orthologous proteins between SKU1100 and IFO3283-01 strains, indicating that the number of Arg-based salt bridges increased in protein models. Since it has been reported that Arg-based salt bridges are important factor for thermo-stability of protein structure, our results strongly suggest that the increased number of Arg-based salt bridges may contributes to the thermotolerance of A. tropicalis SKU1100 (the thermo-stability of proteins in A. tropicalis SKU1100).     

Transgenic prolactin-/- mice: effect of trauma-hemorrhage on splenocyte functions

Prolactin (PRL) is involved in the regulation of immune functions under normal and pathological conditions. Trauma-hemorrhage (T-H) produces profound immunosuppression in male mice but not in proestrus female mice. Administration of PRL in males after T-H, however, restores immune functions. In this study, PRL^+/+ and transgenic (PRL^–/–) male and female mice were used to assess immune suppression after T-H and to determine the reasons for the hormone's beneficial effect. In vitro lymphoproliferation assay with Nb2 cells showed complete absence of PRL in the circulation of the transgenic PRL^–/– mice of both sexes, whereas very high levels of the hormone were detected in the wild-type PRL^+/+ mice of both sexes. Moreover, T-H resulted in the appearance of significant levels of the hormone in circulation, but only in PRL^+/+ mice. Splenocyte proliferation in male PRL^–/– mice was significantly lower than in PRL^+/+ mice after T-H. Marginal differences between PRL^+/+ and PRL^–/– mice were observed in the release of IL-2 and IFN- by splenocytes, while the release of IL-10 was significantly higher in PRL^–/– than in PRL^+/+ mice. A significant observation of our study is the release of a 25-kDa protein in the concanavalin A-stimulated splenocytes of male PRL^+/+ and PRL^–/– mice that was active in the in vitro lymphoproliferation assay with Nb2 cells. It is unlikely that this protein is PRL because it is also present in the splenocyte extracts of PRL^–/– transgenic mice. Nonetheless, because control of lymphoid cell proliferation is considered one of the characteristics of the immune system, the local release of this protein may be significant in the differences observed in splenocyte cytokine release after T-H in wild-type as well as transgenic mice. Nb2 cells; cytokines; immune functions