Complete Nucleotide Sequence and Phylogenetic Analyses of Hepatitis B Virus Isolated from Two Pileated Gibbons

Virus-like particles (VLPs, named HmTV1-17), about 40nm in diameter were found in the violet root rot fungus Helicobasidium mompa Tanaka strain No. 17, which had been isolated from an apple tree. Purified preparations of HmTV1-17 contained two species of double-stranded RNA (dsRNA), designated 17L and 17S. cDNAs were constructed from HmTV1-17 genomic dsRNAs purified using CF-11 cellulose column chromatography. The sequences of 17L and 17S cDNA comprised 5207 and 2096bp, respectively. Although 17S has no large open reading flame (ORF) on either strand, 17L has two large overlapping ORFs. The 5 located ORF1 encodes the coat protein (CP, 788 amino acids), whereas the gene product of ORF2, which is in the –1 frame relative to ORF1, shows the typical features of a RNA dependent RNA polymerase (RDRP, 845 amino acids). Phylogenetic analysis based on RDRP showed that HmTV1-17 is closely related to Sphaeropsis sapinea SsRV1, a member of the genus Totivirus from filamentous fungus S. sapinea.     

Masked excitatory action of noradrenaline on rat islet β-cells via activation of phospholipase C

The effect of noradrenaline (NE) on rat islet -cells was examined. NE reduced insulin secretion from rat islets exposed to extracellular solutions containing glucose at 5.5 or 16.6 mM. In islets treated with pertussis toxin (PTX), however, NE increased insulin secretion. The NE-induced augmentation of insulin secretion was inhibited by prazosin. In intact islets, NE increased phospholipase C (PLC) activity, an effect that was prevented by treatment of islets with U-73122. NE elevated intracellular [Ca²⁺] ([Ca²⁺]_i) in isolated -cells independently of PTX. Although this NE effect was inhibited by prazosin, phenylephrine did not mimic it. The [Ca²⁺]_i response to NE was also prevented by the treatment of cells with U-73122. NE produced depolarization of -cells followed by nifedipine-sensitive action potentials. NE reduced the whole-cell membrane currents through ATP-sensitive K⁺ channels (K_ATP), responsible for the depolarization. This NE effect was prevented by treatment of -cells with U-73122 or BAPTA/AM. Although at least some of our results imply the presence of ₁-adrenoceptors, -cells were not stained by a polyclonal IgG antibody recognizing all adrenergic ₁-receptor subtypes so far identified. These results suggest that an interaction of NE with an unknown type of receptor activates rat islet -cells via a PLC-dependent signal pathway. This effect is, however, masked by the inhibitory action via a PTX-sensitive pathway also activated by NE.     

Follicle structure-dependency of thyroglobulin and thyroxin staining in the thyroid glands of Graves' disease

H.E. morphology of the thyroid glands from 170 patients with Graves' disease was studied, and the thyroid follicles were classified into two main groups: (1) F pattern, in which the follicles show circle/ellipse on cut sections; (2) P pattern, in which the follicular epithelium protrudes into the lumen or a follicle, is accompanied by proliferation of tubular or microfollicular structures. Studies on three serial sections of 88 thyroid glands stained with hematoxylin and eosin, thyroglobulin (TG), and thyroxin (T4), respectively, revealed the followings: (i) TG/T4 staining is dependent on the follicle structure (i.e., F or P); while the epithelium and colloid including scalloped vesicles in F follicles generally exhibited a direct relationship between TG and T4 staining, those in P follicles often showed an intense TG, but negative T4 staining. (ii) The results of morphological and immunohistochemical studies of P follicles among the cases are consistent with the view that P follicles are in the process of proliferation of immature daughter follicles from a main follicle and of their maturation. (iii) P follicles of Graves' thyroid glands were evaluated as possible non-neoplastic counterparts of well-differentiated follicular and papillary tumors.     

Results of definitive radiotherapy with concurrent chemotherapy for maxillary sinus carcinomas with neck lymph node metastasis

The purpose of this study was to describe the results of definitive radiotherapy (RT) with concurrent chemotherapy for maxillary sinus carcinomas (MSCs) with neck lymph node metastasis to clarify its limitation. Local control (LC), progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan–Meier method and were compared between subgroups using the log rank test. Toxicity was classified using common terminology criteria of adverse events version 5.0. Eighteen patients with inoperable MSC with neck lymph node metastasis including 12 men and 6 women with a median age of 67 years were analyzed. The histologic diagnoses were as follows: 16 patients had squamous cell carcinomas and 2 had other histology. Four patients had stage T3 MSC, 6 had T4a and 8 had T4b. Among 18 patients, 7 received concurrent systemic chemotherapy and 11 received selective arterial chemo-infusion. The median follow-up period was 17 months. The 2-year LC, PFS and OS rates for the entire cohort were 34, 31 and 46%, respectively. No significant differences were observed for LC, PFS and OS rates between systemic chemotherapy and selective arterial chemo-infusion cohorts. Grade 3 or higher acute toxicity, including both non-hematological and hematological, was observed in nine patients (50%), while no grade 3 or higher late toxicity was observed. In conclusion, we described the results of definitive RT for MSCs with neck lymph node metastasis. Local recurrence of primary tumor was a frequent pattern of failure and it should be addressed in future study.     

Cdc7 kinase is required for postnatal brain development

The evolutionally conserved Cdc7 kinase plays crucial roles in initiation of DNA replication as well as in other chromosomal events. To examine the roles of Cdc7 in brain development, we have generated mice carrying Cdc7 knockout in neural stem cells by using Nestin-Cre. The Cdc7^Fl/Fl Nestin^Cre mice were born, but exhibited severe growth retardation and impaired postnatal brain development. These mice exhibited motor dysfunction within 9 days after birth and did not survive for more than 19 days. The cerebral cortical layer formation was impaired, although the cortical cell numbers were not altered in the mutant. In the cerebellum undergoing hypoplasia, granule cells (CGC) decreased in number in Cdc7^{Fl/F l}Nestin^Cre mice compared to the control at E15-18, suggesting that Cdc7 is required for DNA replication and cell proliferation of CGC at mid embryonic stage (before embryonic day 15). On the other hand, the Purkinje cell numbers were not altered but its layer formation was impaired in the mutant. These results indicate differential roles of Cdc7 in DNA replication/cell proliferation in brain. Furthermore, the defects of layer formation suggest a possibility that Cdc7 may play an additional role in cell migration during neural development.     

Micro-mainframe-link Personal Clinical Research System

We constructed a micro-mainframe-link clinical research system for personal use (Personal Clinical Research System). This system was developed with both a mainframe computer and a personal computer (PC). The prepared programs included a database manager (on the mainframe computer), a user interface program (on the PC), and a communication control program that connected the mainframe computer with the PC. The database on the mainframe computer was constructed by two methods. The first method was to transmit data from the PC to the mainframe computer. The second method was to extract data from the patient information database. Using this system, a physician is able to construct a personal research database that contains interesting data for the physician. In addition, the physician is able to accumulate data on a special field using this system. A discharge summary system is now in operation as an example of this system.     

Cerebral atrophy in multiple system atrophy by MRI

Cranial magnetic resonance images (MRI) of the cerebral areas of 40 patients with multiple system atrophy (MSA) and of 61 age-matched controls were analyzed. The cerebral area of MSA patients was 131. 95+/-15.89 cm(2) (mean+/-S.D.), which was significantly smaller than that of normal controls at 149.01+/-10.93 cm(2) (P<0.0001). All 23 MSA cases subjected to the MRI study over a 1-year period showed progressive cerebral atrophy, and the atrophy rate was 2.46+/-1. 66%/year. There were no significant differences within the MSA subtypes or between gender. The progression of cerebral atrophy in MSA correlated more with duration (r=-0.634) than age (r=-0.421). We conclude that MRI findings throughout the course of MSA suggest progressive cerebral atrophy, which is common in all subtypes and reflects duration of the disease rather than age.     

Suppressive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the high-affinity antibody response in C57BL/6 mice.

In the humoral immune response to an invasion of foreign antigens, B cells differentiate into low-affinity antibody-forming cells (AFCs) that mainly secrete IgM or, through germinal center (GC) formation, into high-affinity AFCs that secrete IgG-class antibodies with a higher affinity for the antigen. Previous studies have established the suppressive effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on low-affinity antibody responses to antigens. However, whether and how TCDD affects the high-affinity antibody response to antigens has not yet been clarified. In this paper we investigate the effects of TCDD on GC formation, high-affinity AFC generation, and high-affinity antibody production in the primary humoral immune response. C57BL/6 mice were orally administered 0 or 20 microg/kg of TCDD and subsequently immunized with alum-precipitated ovalbumin (OVA) on day 0. Then the GC formation in the spleen and OVA-specific antibodies in the plasma, was evaluated until day 14 postimmunization. TCDD exposure reduced the production of OVA-specific IgG1 on days 10 and 14. GC formation in the spleen was also suppressed by TCDD exposure, and the suppression persisted from day 7 until day 14. In TCDD-administered mice, on day 7, cellular proliferation in the GCs was significantly suppressed, although apoptosis was not markedly affected. In order to measure high-affinity antibody and high-affinity AFCs, the mice were administered TCDD followed by immunization with alum-precipitated (4-hydroxy-3-nitrophenyl) acetyl linked to chicken gamma-globulin (NP-CG). The frequency of high-affinity NP-specific AFCs that bind to low-haptenated antigen was clearly shown to be reduced in the spleen on days 10 and 14. Furthermore, the high-affinity anti-NP IgG1 levels on days 10 and 14 postimmunization were significantly reduced by TCDD exposure. Taken together, the results of this paper demonstrate that TCDD exposure inhibits the generation of high-affinity AFCs and high-affinity antibody production during the primary humoral immune response and suggest that these alterations were caused by the suppression of antigen-responding B-cell proliferation induced by TCDD during GC formation.