Low-dose recombinant human hepatocyte growth factor enhances effect of hepatocyte transplantation in rats treated with retrorsine.

BACKGROUND/AIMS: The aim of this study was to regenerate transplanted hepatocytes selectively in a recipient using retrorsine and recombinant human hepatocyte growth factor (rhHGF). METHODOLOGY: Nagase analbuminemic rats (NARs) received pretreatment with retrosine and were divided into three experimental groups. Group1: Hepatocyte transplantation (HcTx) + 50 microg/kg/day rhHGF. Group2: HcTx + 250 microg/kg/day rhHGF. Group3: HcTx + normal saline. The serum levels of albumin and the albumin-positive hepatocytes in the liver were investigated. The rat endogenous HGF of the rats given only retrorsine was measured. RESULTS: The serum albumin levels of Group11 were higher than those of Group2, while there was no significant difference between Group2 and GroupS. Histological examination of Group1 and 3 showed the presence of a large number of albumin-positive hepatocytes, which frequently consisted of large clusters and occupied 53.90 +/- 2.31% and 31.25 +/- 5.36% of host liver, respectively. The liver sections of Group2 showed numerous albumin-positive hepatocyte, which were not seen as clusters. The rat endogenous HGF concentration was extremely high. CONCLUSION: Low-dose rhHGF enhances the effect of HcTx under the suppressive state of proliferation of host hepatocytes. Because of the high endogenous HGF, the administration of a high concentration of rhHGF suppressed the regenerative activity of the transplanted hepatocytes

The Asia‐Pacific Biodiversity Observation Network : 10‐year achievements and new strategies to 2030.

The Asia-Pacific Biodiversity Observation Network (APBON) was launched in 2009, in response to the establishment of the Biodiversity Observation Network under the Group on Earth Observations in 2008. APBON's mission is to increase exchange of knowledge and know-how between institutions and researchers concerning biodiversity science research in the Asia-Pacific (AP) region and thereby contribute to evidence-based decision-making and policy-making. Here we summarize APBON activities and achievements in its first 10 years. We review how APBON has developed networks, facilitated communication for sharing knowledge, and built capacity of researchers and stakeholders through workshops and publications as well as discuss the network plan. Key findings by APBON members include descriptions of species new to science, mapping tropical forest cover change, evaluating impacts of hydropower dams and climate change on fish species diversity in the Mekong, and mapping “Ecologically and Biologically Significant Areas” in the oceans. APBON has also contributed to data collection, sharing, analysis, and synthesis for regional and global biodiversity assessment. A highlight was contributing to the “Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services” regional report. New strategic plans target the development of national-level BONs and interdisciplinary research to address the data and knowledge gaps and increase data accessibility for users and for meeting societal demands. Strengthening networks in AP region and capacity building through APBON meetings will continue. By promoting monitoring and scientific research and facilitating the dialogue with scientists and policymakers, APBON will contribute to the implementation of conservation and sustainable use of biodiversity in the entire AP region.publishedVersio

Inflammatory bowel disease in Tokushima prefecture : A report of questionnaire investigation

To investigate the number of cases and clinical features of inflammatory bowel disease, a questionnaire was sent to 1,271 hospitals or clinics in Tokushima prefecture. A total of 320 cases were collected from 60 institutes for the period from January to December 1997. Eight cases were excluded from this study because of duplicated report (6 cases) and inadequate diagnosis (2 cases). Finally, 312 cases were investigated on their clinical features, treatments, complications, and prognosis. The cases included 195 ulcerative colitis (male 106, female 83, gender unknown 6 cases, age ranged 9-81, mean 39.5± 14.3 (standard deviation (SD) years old), 69 Crohn's disease (male 39, female 24, gender unknown 6 cases, age ranged 17-87, mean 35.1±10.5 (SD) years old), 28 ischemic colitis (male 11, female 17, mean age 65.9±12.6 (SD) years old), 9 intestinal tuberculosis (male 1, female 6, gender unknown 2, age 66.9±6.1 (SD) years old), 4 intestinal Behcet (male 3, female 1, age 39.0±14.2 (SD) years old), 6 simple ulcers (male 3, female 3, age 67.7±11.8 (SD) years old), and a case of aphtous enteritis. Two toxic megacolon cases and 5 colorectal cancer cases were reported among the 195 ulcerative colitis patients. 44 cases out of 69 Crohn's disease patients were received surgical treatment because of severe complications including perforation (12 cases), stenosis (10 cases), internal fistula formation (8 cases) and so on. However, no case died because of the diseases except 3 untraceable patients

Preparation and Evaluation of a Powdered Rebamipide Mouthwash as In-Hospital Formulation: Considering Dispersion before Use in Patients

In Japan, rebamipide (RB) mouthwash (RB-MW) for oral mucositis induced by cancer chemotherapy has been prepared using in-hospital formulation. Usually, RB-MW is prepared by dispersing crushed commercial RB tablets in the dispersion medium; however, uniformity is difficult to obtain due to low solubility. The current study aims is to prepare homogenously dispersed formulations using the fine particles of crushed tablets by a method that is convenient for hospital use. Commercial RB tablets were pre-milled at different milling times as “RB-Ts”. A ground mixture was then prepared by co-grinding the RB-Ts with HPC-L or PVP K30 via a benchtop ball milling machine (MM400). The physicochemical properties of samples were evaluated for PXRD, FTIR, turbidity, particle size, and solubility. Although the milling of RB tablets decreased the crystallinity, the length of milling time did not affect them. In contrast, grinding using MM400 significantly decreased RB crystallinity; their PXRD patterns showed a halo, suggesting the amorphization of RB crystals by grinding. Although solubility and turbidity seemed to be affected by the type of polymer rather than the particle size, every ground mixture showed high dispersibility. Thus, grinding the RB-Ts with polymers appeared to be the most promising way to obtain stable dispersion as an in-hospital formulation

Stochastic modeling for gradient sensing by chemotactic cells.

Abstract Chemotaxis, the process by which cells move toward attractant molecules, operates in a range of biological processes including immunity, neuronal patterning, and morphogenesis. Dictyostelium discoideum cells display a strong chemotactic response to cyclic adenosine 3 0 ,5 0 -monophosphate (cAMP), which binds to a cell surface receptor. Each Dictyostelium has ca. 80000 cAMP receptors, and can transduce shallow spatial chemoattractant gradients into strongly localized intracellular responses in spite of large statistical fluctuation of receptor occupancy even in the case of very low cAMP concentration. In this study, we develop a stochastic model for gradient sensing by chemotactic cells. We simulate the binding of cAMP molecules to receptors by a Monte-Carlo method in order to account for statistical fluctuation of receptor occupancy and treat intracellular signal processing by a diffusion-translocation model, which includes the production of second-messenger molecules and positive feedback mechanisms mediated by effector molecules. Our simulation results show that the fluctuation of second-messenger concentration is much smaller than that of receptor occupancy, and that a shallow chemoattractant gradient are transduced into a large second-messenger concentration gradient through nonlinear signal amplification.

Preparation and Evaluation of Rebamipide Colloidal Nanoparticles Obtained by Cogrinding in Ternary Ground Mixtures

Aphthous stomatitis is one of the side effects of chemotherapy and radiotherapy in cancer treatment. Rebamipide (RB) mouthwash for stomatitis acts as a radical scavenger. However, RB is poorly soluble in water, which leads to aggregation and precipitation of the dispersoid. The particle size of the drug needs to be less than 100 nm for the particles to reach the mucus layer in the oral cavity. In this study, we attempted to prepare nanoparticles of RB by cogrinding with polyvinylpyrrolidone (PVP) or hydroxypropyl cellulose (HPC) and sodium dodecyl sulfate (SDS) using a mixer ball mill, and evaluated the physicochemical properties of RB nanoparticles, the stability of dispersion in water, and permeation of the mucus layer in vitro. By cogrinding, the particle size decreased to around 110 nm, and powder X-ray diffraction (PXRD) of the particles showed totally broad halo patterns, which suggested a decreased crystalline region. Furthermore, the solubility of RB nanoparticles increased by approximately fourfold compared with RB crystals, and the water dispersibility and permeation of the mucus layer were improved. The results suggest that in a ternary ground mixture of RB, PVP or HPC, and SDS, the RB nanoparticles obtained can be applied as a formulation for stomatitis