Biotransformation of phenolic compounds by the cultured cells of Catharanthus roseus

The cultured cells of Catharanthus roseus were able to convert 2-, 3-, and 4-hydroxybenzyl alcohols into their corresponding hydroxybenzyl-β- -glucopyranosides or β- -glucopyranosylbenzyl alcohols, and then convert 2- and 3-hydroxybenzyl-β- -glucopyranosides into primeverosides and vicianosides. Further, the C. roseus cells were capable of hydroxylation of 2-hydroxybenzoic acid to afford 2,5-dihydroxybenzoic acid and then glucosylation of the newly introduced phenolic hydroxyl group.     

Cytological study of early cervical adenocarcinoma: special reference to the depth of invasion

OBJECTIVE: Early cervical adenocarcinoma (ECA) with a tumour depth of <3 mm has a good prognosis. To clarify the cytological features of ECAs with depth <3 mm, these were compared with those of ECA with 3-5 mm and invasive adenocarcinoma (IA) invading the cervical wall with more than 5 mm in depth. METHODS: The cervical cytological features of ECAs with depth <3 mm (14 cases) were compared with those of ECA with 3-5 mm (four cases) and IA (13 cases). Cytologically, the presence or absence of tumour diathesis, number of atypical cells, crowded cell groups, groups with glandular structures, feathering, groups with palisading borders, rosettes, clusters, cell shape and size, nuclear shape and size, nucleolar shape and size, chromatin distribution, border and character of cytoplasm, and single cell pattern were evaluated. RESULTS: A tumour diathesis was seen in five of 14 ECA <3 mm in depth (36%), all four ECA with 3-5 mm (100%) and 11 of 13 IA with more than 5 mm (85%). Single cells, macronucleoli and coarsely granular chromatin pattern were less frequent in ECA of <3 mm than that in ECA with 3-5 mm and IA. The number of atypical cells and glandular structures in ECA was significantly less than that in IA. Cell crowding, feathering, palisading and rosettes were common in both ECA and IA. CONCLUSION: The characteristic cytological features of ECA with depth <3 mm, having a good prognosis, were clean background, fewer single cells and macronucleoli, and less frequent coarsely granular chromatin pattern compared with those in ECA with 3-5 mm and IA. The number of atypical cells and glandular structures in ECA was significantly less than that in IA. Familiarity with the cytological features of ECA and its mimics is essential.     

Localization and effects of hepatocyte growth factor on smooth muscle cells during neointimal formation after balloon denudation

The migration and proliferation of smooth muscle cells (SMCs) may play a key role in tissue remodeling after arterial wall injury. We investigated the localization and effects of hepatocyte growth factor (HGF) in rabbit carotid arteries after balloon denudation. Immunoreactivity for HGF and the c-Met receptor was clearly observed in neointimal SMCs. The immunoreactivity was not restricted to proliferating cells but was seen even in non-dividing cells in the basal layer of the neointima 4 and 6 weeks after balloon denudation. The distribution of platelet-derived growth factor (PDGF)-positive cells paralleled that of proliferating SMCs. The SMCs in the basal layer of the neointima at 4 and 6 weeks were positive for matrix metalloproteinase (MMP)-2 and membrane type 1-MMP which can activate the proform of MMP-2. HGF significantly stimulated the migration but not proliferation of cultured SMCs. Our results suggest that HGF and PDGF act in coordination to promote the proliferation and migration of SMCs in the earlier phases of neointimal formation and that HGF as well as MMP-2 contribute to the later stages by facilitating the migration but not replication of SMCs. Accepted: 19 March 1999     

A management policy for sika deer based on sex-specific hunting

We consider here a management policy for a sika deer (Cervus nippon) population in the eastern part of Hokkaido. Deer populations are characterized by a large intrinsic rate of population increase, no significant density effects on population growth before population crash, and a relatively simple life history. Our goals of management for the deer population are (1) to avoid irruption with severe damage to agriculture and forestry, (2) to avoid the risk of extinction of the deer population, and (3) to maintain a sustainable yield of deer. To make a robust program on the basis of uncertain information about the deer population, we consider three levels of relative population size and four levels of hunting pressures. We also take into consideration a critical level for extinction, an optimal level, and an irruption level. The hunting pressure for females is set to increase with the population size. We also recommend catching males if the population size is between the critical and optimal levels and catching females and males if the population size is larger than the optimal level. We must avoid cases of irruption or threatened population under various sets of uncertain parameter values. The simulation results suggest that management based on sex-specific hunting is effective to diminish the annual variation in hunting yield. Received: April 8, 1998 / Accepted: December 25, 1998     

A gene for fluctuating, progressive autosomal dominant nonsyndromic hearing loss, DFNA16, maps to chromosome 2q23-24.3.

The sixteenth gene to cause autosomal dominant nonsyndromic hearing loss (ADNSHL), DFNA16, maps to chromosome 2q23-24.3 and is tightly linked to markers in the D2S2380-D2S335 interval. DFNA16 is unique in that it results in the only form of ADNSHL in which the phenotype includes rapidly progressing and fluctuating hearing loss that appears to respond to steroid therapy. This observation suggests that it may be possible to stabilize hearing through medical intervention, once the biophysiology of deafness due to DFNA16 is clarified. Especially intriguing is the localization of several voltage-gated sodium-channel genes to the DFNA16 interval. These cationic channels are excellent positional and functional DFNA16 candidate genes.     

A group of schwannomas with interstitial deletions on 22q located outside the NF2 locus shows no detectable mutations in the NF2 gene

Schwannomas are tumors arising mainly at cranial and spinal nerves. Bilateral vestibular schwannoma is the hallmark of neurofibromatosis type 2 (NF2). The NF2 gene has been cloned and comprehensive analysis of its mutations in schwannomas shows that up to 60% of tumors carry inactivating mutations. Thus, the genetic mechanism behind the development of more than 40% of schwannomas without NF2 mutations is unknown. We have therefore studied tumor tissue from 50 human schwannomas by allelotyping and have found chromosome 22 deletions in over 80% of the cases. We detected 14 cases (27%) that revealed partial deletions of one copy of chromosome 22, i.e., terminal and/or interstitial deletions. We sequenced the NF2 gene in seven of these tumors and detected only one case with mutations. The deletion mapping of chromosome 22 in tumors with partial deletions indicates that several regions, in addition to the NF2 locus, harbor genes involved in schwannoma tumorigenesis. Our findings suggest that heterogeneity in the mechanisms leading to the development of schwannomas probably exists. These findings are in agreement with the recent analysis of schwannomas from familial and sporadic cases of schwannomatosis and point to a possible role of an additional gene, which, in cooperation with the NF2 tumor suppressor, causes schwannomas. Received: 12 November 1998 / Accepted: 1 March 1999     

Successful treatment for perinephric abscess with recombinant human granulocyte colony-stimulating factor following nephrectomy in a patient of myelodysplastic syndrome: A case report

The 35-year-old man with myelodysplastic syndrome (MDS) and granulocytopenia with dry cough and high fever was eventually found to have a left perinephric abscess ofStaphylococcus aureus. He underwent left nephrectomy and drainage of perinephric space in conjunction with appropriate antibiotics. However, because of persistent granulocytopenia,Staph. aureus never cleared up with formation of only poor granulation. Recombinant human granulocyte colony-stimulating factor (G-CSF) was added to the above treatment leading to prompt improvement in granulocytopenia and emergence of the good granulation tissue. G-CSF will probably become one of the important agents in treating MDS with granulocytopenia.     

Embryonic Medaka Model of Microglia in the Developing CNS Allowing In Vivo Analysis of Their Spatiotemporal Recruitment in Response to Irradiation

Radiation therapy (RT) is pivotal in the treatment of many central nervous system (CNS) pathologies; however, exposure to RT in children is associated with a higher risk of secondary CNS tumors. Although recent research interest has focused on the reparative and therapeutic role of microglia, their recruitment following RT has not been elucidated, especially in the developing CNS. Here, we investigated the spatiotemporal dynamics of microglia during tissue repair in the irradiated embryonic medaka brain by whole-mount in situ hybridization using a probe for Apolipoprotein E (ApoE), a marker for activated microglia in teleosts. Three-dimensional imaging of the distribution of ApoE-expressing microglia in the irradiated embryonic brain clearly showed that ApoE-expressing microglia were abundant only in the late phase of phagocytosis during tissue repair induced by irradiation, while few microglia expressed ApoE in the initial phase of phagocytosis. This strongly suggests that ApoE has a significant function in the late phase of phagocytosis by microglia in the medaka brain. In addition, the distribution of microglia in p53-deficient embryos at the late phase of phagocytosis was almost the same as in wild-type embryos, despite the low numbers of irradiation-induced apoptotic neurons, suggesting that constant numbers of activated microglia were recruited at the late phase of phagocytosis irrespective of the extent of neuronal injury. This medaka model of microglia demonstrated specific recruitment after irradiation in the developing CNS and could provide a useful potential therapeutic strategy to counteract the detrimental effects of RT.     

Spatiotemporal Regulation of the Ubiquitinated Cargo-binding Activity of Rabex-5 in the Endocytic Pathway

Ubiquitin (Ub)-dependent endocytosis of membrane proteins requires precise molecular recognition of ubiquitinated cargo by Ub-binding proteins (UBPs). Many UBPs are often themselves monoubiquitinated, a mechanism referred to as coupled monoubiquitination, which prevents them from binding in trans to the ubiquitinated cargo. However, the spatiotemporal regulatory mechanism underlying the interaction of UBPs with the ubiquitinated cargo, via their Ub-binding domains (UBDs) remains unclear. Previously, we reported the interaction of Rabex-5, a UBP and guanine nucleotide exchange factor (GEF) for Rab5, with ubiquitinated neural cell adhesion molecule L1, via its motif interacting with Ub (MIU) domain. This interaction is critical for the internalization and sorting of the ubiquitinated L1 into endosomal/lysosomal compartments. The present study demonstrated that the interaction of Rabex-5 with Rab5 depends specifically on interaction of the MIU domain with the ubiquitinated L1 to drive its internalization. Notably, impaired GEF mutants and the Rabex-5^E213A mutant increased the flexibility of the hinge region in the HB-VPS9 tandem domain, which significantly affected their interactions with the ubiquitinated L1. In addition, GEF mutants increased the catalytic efficiency, which resulted in a reduced interaction with the ubiquitinated L1. Furthermore, the coupled monoubiquitination status of Rabex-5 was found to be significantly associated with interaction of Rabex-5 and the ubiquitinated L1. Collectively, our study reveals a novel mechanism, wherein the GEF activity of Rabex-5 acts as an intramolecular switch orchestrating ubiquitinated cargo-binding activity and coupled monoubiquitination to permit the spatiotemporal dynamic exchange of the ubiquitinated cargos.