Clinical significance of reverse redistribution in exercise thallium-201 SPECT after percutaneous transluminal coronary angioplasty

Clinical significance of reverse redistribution on thallium image was evaluated in 54 patients who had undergone PTCA. Thallium SPECT imaging was performed one week and three to six months after PTCA. Reverse redistribution was detected eight of 54 patients one week after PTCA and five of 38 patients three to six months after PTCA. In the segments with reverse redistribution, reduced regional wall motion and lesser degree of coronary stenosis was common features (p less than 0.05) angiography. In conclusion, reverse redistribution had a tendency to appear in the region with mild myocardial injury and relatively high coronary blood flow after PTCA. But in cases with new occurrence and disappearance of reverse redistribution during follow up period, we can not assess the factors to explain these phenomena. In these segments, "coronary flow reserve", "stunned myocardium", "hibernating myocardium" or other factors may be related.     

Diurnal changes in colonic motility in conscious dogs

Daily profile of colonic motor activity was observed in 10 conscious dogs by means of extraluminal force transducers. Each dog was implanted with a set of seven strain, gauges, one on the terminal ileum and the remaining six on the colon equidistantly. The colonic motor activity was basically composed of migrating and non-migrating motor complexes at all six recording sites. Each motor complex was characterized by a tonic contraction superimposed by rhythmic bursts of phasic contractions. During fasted period these motor complexes recurred at a mean interval of 36 min, and a mean duration was 7 to 12 min. Those motor complexes which migrated over at least three recording sites were defined as "migrating", 72% of those observed at the most proximal sites (n = 2680) were migrating, and the remaining 28% were non-migrating. Of those migrating motor complexes 90.4% migrated caudad (iso-peristalsis), while only 9.4% migrated orad (antiperistalsis). During postprandial period the colonic motor complexes at all recording sites uniformly increased their frequency with shorter intervals. Different from the small intestine, the contractile patterns were essentially the same as those of fasted period. The postprandial acceleration of the colonic motor complexes seems to be compatible with gastrocolic response.     

Concomitant translocation of Puralpha with its binding proteins (PurBPs) from nuclei to cytoplasm during neuronal development

Two Puralpha-binding proteins (PurBPs) were found in nuclear extract from mouse brain during P4-P10 by the overlay assay. At P14, they were decreased significantly in nuclear extract and increased in the S3 fraction, indicating their dynamic translocation during development. Western blot analysis also demonstrated concomitant translocation of Puralpha with the PurBPs during P7-P14, when neuronal circuit proceeds. Immunocytochemical study with cultured hippocampal neurons from rat E18 confirmed that nuclear Puralpha was translocated to cytoplasm after plating for 7-14 days. These results suggest that spatiotemporal translocation of Puralpha with the PurBPs from nuclei to cytoplasm has a crucial role in neuronal development.     

Characterization of htAKR, a novel gene product in the aldo-keto reductase family specifically expressed in human testis

In human testis, expression of a novel member of the aldo-keto reductase family was identified. Based on its testis-specific expression, we termed this protein human testis aldo-keto reductase (htAKR). In addition to four major isoforms, the existence of multiple alternatively spliced products of htAKR was detected using RT-PCR followed by nested PCR. htAKR was a homologue of mouse liver keto-reductase, AKR1E1, with close similarity in their genomic organizations. htAKR4, the longest isoform, was expressed as a non-fused native form. It exhibited a limited activity toward 9,10-phenanthrenequinone, while no activity toward the steroids or prostaglandins was demonstrated. Using the laser capture microdissection technique and RT-PCR, expression of htAKR was detected in testicular germ cells as well as in interstitial cells. The levels of htAKR mRNA in the tissues obtained from seminoma were much lower than those in normal testes. A significant decline in the htAKR expression was observed when NEC8, a cell line originated from a human testicular germ cell tumour, was exposed to phorbol 12-myristate 13-acetate or 5alpha-dihydrotestosterone. These results indicate that the expression of htAKR, down-regulated in the testicular tumour, is possibly controlled by mitogenic and hormonal signals.     

Divergent expression and localization of aquaporin 5, an exocrine-type water channel,in the submandibular gland of Sprague-Dawley rats

By Western blot analysis, the expression level of aquaporin (AQP) 5 in the submandibular gland (SMG) was found to be different among individual rats of the Sprague-Dawley (SD) strain. Such differences were observed for AQP5 but not for AQP1 and consequently the SD strain was divided into two groups, one expressing a high level of AQP5 and the other a low one. The difference in average intensity of expression between the two groups was more than twofold. Immunohistochemical analysis of the SMG demonstrated that the AQP5 protein was localized in the basal and apical/lateral plasma membrane of acinar cells in rats expressing the high level of AQP5. In the rat expressing the low level, however, this channel protein was localized strongly in the apical/lateral plasma membrane, but only very weakly in the basal membrane of the acinar cells. Such a diverse localization of AQP5 was confirmed by Western blotting as well. Breeding between brother and sister was repeated for two times within high expressers and low expressers to obtain the third generation progenies (F2); the AQP5 level of the SMG in the third generation (F2 rats) from high expressers was significantly higher than the F2 from low expressers. Our present study suggests the existence of genetic variation in the expression of a water channel protein, AQP5, in rats.     

Role of alphabeta and gammadelta T cells in the host response to Salmonella infection as demonstrated in T-cell-receptor-deficient mice of defined Ity genotypes.

Salmonella spp. are facultative intracellular bacteria which enter the body through the intestinal tract. We studied the roles of T cells expressing either the alpha and beta chains or the gamma and delta chains of the T-cell receptor (alphabeta T cells or gammadelta T cells, respectively) in the host defense against Salmonella using mice genetically deficient in either alphabeta T cells, gammadelta T cells, or both T-cell subsets. These mutant strains of mice were infected orally or intraperitoneally with Salmonella dublin, and the progression of the disease was monitored by determining bacterial numbers in the feces, gut wall, Peyer's patches, mesenteric lymph nodes, spleen, and liver. Since susceptibility to Salmonella infection in mice is strongly affected by the alleles at the Ity locus, T-cell-mutant mice with either the Ity-sensitive or Ity-resistant phenotype were tested for resistance to S. dublin infection. We found that even though large numbers of intraepithelial and mucosal alphabeta and gammadelta T cells populate the normal intestine, they have no role in controlling the invasion of S. dublin into the intestine or the subsequent bacterial replication in the Peyer's patches or gut wall. Furthermore, systemic infections were equally severe for the first 6 days in normal, alphabeta T-cell-deficient, and gammadelta T-cell-deficient mice, and alphabeta but not gammadelta T cells were required for clearance of S. dublin, regardless of the Ity phenotype. However, mice that lacked both T-cell subsets had higher bacterial counts in their livers 15 to 18 days after infection than did alphabeta T-cell-deficient mice, suggesting that gammadelta T cells can contribute to acquired immunity to S. dublin.     

Intracellular vesicular stomatitis virus nucleocapsids and virions visualized by surface spreading

Spreading of cells on a solution surface could visualize vesicular stomatitis virus nucleocapsids and virions in infected cells easily and clearly without the need for any purification. Characteristic structures observed by the spreading of the infected cells are described and discussed.     

Regulation of Fungal Infection by a Combination of Amphotericin B and Peptide 2, a Lactoferrin Peptide That Activates Neutrophils

To establish a novel strategy for the control of fungal infection, we examined the antifungal and neutrophil-activating activities of antimicrobial peptides. The duration of survival of 50% of mice injected with a lethal dose of Candida albicans (5 × 10⁸ cells) or Aspergillus fumigatus (1 × 10⁸ cells) was prolonged 3 to 5 days by the injection of 10 μg of peptide 2 (a lactoferrin peptide) and 10 μg of α-defensin 1 for five consecutive days and was prolonged 5 to 13 days by the injection of 0.1 μg of granulocyte-monocyte colony-stimulating factor (GM-CSF) and 0.5 μg of amphotericin B. When mice received a combined injection of peptide 2 (10 μg/day) with amphotericin B (0.5 μg/day) for 5 days after the lethal fungal inoculation, their survival was greatly prolonged and some mice continued to live for more than 5 weeks, although the effective doses of peptide 2 for 50 and 100% suppression of Candida or Aspergillus colony formation were about one-third and one-half those of amphotericin B, respectively. In vitro, peptide 2 as well as GM-CSF increased the Candida and Aspergillus killing activities of neutrophils, but peptides such as α-defensin 1, β-defensin 2, and histatin 5 did not upregulate the killing activity. GM-CSF together with peptide 2 but not other peptides enhanced the production of superoxide (O₂⁻) by neutrophils. The upregulation by peptide 2 was confirmed by the activation of the O₂⁻-generating pathway, i.e., activation of large-molecule guanine binding protein, phosphatidyl-inositol 3-kinase, protein kinase C, and p47^phox as well as p67^phox. In conclusion, different from natural antimicrobial peptides, peptide 2 has a potent neutrophil-activating effect which could be advantageous for its clinical use in combination with antifungal drugs.