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Leaf venation develops complex patterns in angiosperms, but the mechanism underlying this process is largely unknown. To elucidate the molecular mechanisms governing vein pattern formation, we previously isolated vascular network defective (van) mutants that displayed venation discontinuities. Here, we report the phenotypic analysis of van4 mutants, and we identify and characterize the VAN4 gene. Detailed phenotypic analysis shows that van4 mutants are defective in procambium cell differentiation and subsequent vascular cell differentiation. Reduced shoot and root cell growth is observed in van4 mutants, suggesting that VAN4 function is important for cell growth and the establishment of venation continuity. Consistent with these phenotypes, the VAN4 gene is strongly expressed in vascular and meristematic cells. VAN4 encodes a putative TRS120, which is a known guanine nucleotide exchange factor (GEF) for Rab GTPase involved in regulating vesicle transport, and a known tethering factor that determines the specificity of membrane fusion. VAN4 protein localizes at the trans-Golgi network/early endosome (TGN/EE). Aberrant recycling of the auxin efflux carrier PIN proteins is observed in van4 mutants. These results suggest that VAN4-mediated exocytosis at the TGN plays important roles in plant vascular development and cell growth in shoot and root. Our identification of VAN4 as a putative TRS120 shows that Rab GTPases are crucial (in addition to ARF GTPases) for continuous vascular development, and provides further evidence for the importance of vesicle transport in leaf vascular formation.

At Toho University School of Medicine, first year students are assigned a 30-hour group research project in the 2nd semester. The objective of this project is for students to master essential problem-solving approaches. The staff of the Medical Media Center of Toho University have assisted students in their studies since 2001. To facilitate this process, each department of the Center selects reference tools, purchases relevant materials, instructs the students in the use of the Center collections, and exhibits related information resources. This report details the nature of this support, the content of the group research project and issues that remain to be addressed.

Although branched chain amino acid (BCAA) supplementation improves malnutrition in cirrhotic patients, patient compliance with the administration of BCAA-rich supplements is poor due to their bitter taste. Since temperature is an important factor affecting taste, we examined the effect of heating on the stability of BCAAs and on the compliance of patients with liver cirrhosis with BCAA-rich supplement administration. A thermal denaturation test was first conducted, in which the BCAA-rich supplement Aminoleban® EN was heated to 37, 60, or 80°C for 30 or 60 min. The concentration of three amino acids, L-valine, L-leucine and L-isoleucine, was subsequently measured. The nutritional status of the cirrhotic patients was also evaluted. Patients presenting liver failure with a Child-Pugh class of A (n=2), B (n=2) or C (n=2) were hospitalized at Kurume University Hospital. Six patients with liver cirrhosis (HCV, n=3; HBV, n=1; alcohol, n=2) were enrolled. Venous blood samples were drawn in the morning after a 12-h overnight fast. The BCAA-rich supplement was administered to patients at room temperature (25°C) or heat loaded at 60°C for 10 min, with the temperature maintained above 45°C. Each patient was interviewed by a nationally registered dietitian regarding food consumption and intake of the BCAA-rich supplement immediately after each meal. Nutritional status was evaluated according to serum albumin levels, blood hemoglobin, prothrombin time and total lymphocyte count. No significant decrease was noted in valine, leucine or isoleucine levels following the heating of the BCAAs to 80°C. The caloric intake of the BCAA-rich supplement was significantly higher with administration after heating to 60°C, compared to caloric intake with administration at 25°C. In addition, heating of the BCAA-rich supplement significantly increased blood lymphocyte counts. In conclusion, heating did not affect the stability of the BCAAs, and may improve compliance with BCAA-rich supplement administration. As a result, the nutritional status of cirrhotic patients may be improved.

Aim: Cirrhotic patients tend to develop malnutrition by fasting, yet the importance of nutritional care during examination-associated fasting has not been investigated. This study aimed to examine the effects of a nutritional supplement on nutrition and stresses caused by examination-associated fasting in cirrhotic patients. Methods: Twenty-nine cirrhotic patients were enrolled in this study. No energy was supplied to patients in the fasting group (n = 11) prior to computed tomography or magnetic resonance imaging examination. A supplement of 200 kcal was given to the patients in the supplement group (n = 18) prior to computed tomography or magnetic resonance imaging examination. The effect of the supplement on stresses was evaluated by self-rating questionnaire. Changes in biochemical parameters were also investigated before and after computed tomography or magnetic resonance imaging examinations. Results: There were no significant differences in age, sex, body mass index, or liver function tests between the two groups at the start of the study. In the supplement group, stress scores for physical symptoms (thirst and light-headedness) and mental symptoms (hunger, hypodynamia and fatigue) were significantly lower compared to those in the fasting group. Also in the supplement group, peripheral 3-hydroxybutyric acid and free fatty acids levels were significantly decreased compared to those in the fasting group, to within normal ranges. In addition, a decrease in prothrombin time was significantly inhibited by intake of the supplement. Conclusion: We demonstrated that a nutritional supplement improved nutrition and reduced both the physical and mental stresses associated with examination-associated fasting in cirrhotic patients.

Body cell mass (BCM) is a nutritional parameter, however, changes in BCM in patients with non-ascitic liver cirrhosis (LC) in comparison to patients with other malnutritional diseases remains unclear. We investigated the difference in BCM between patients with LC and malnourished gastrointestinal disease controls (M.CON), and examined the relationship between BCM and the severity of LC. Results demonstrated that serum nutritional parameters were not significantly different between the LC (n=56) and M.CON groups (n=25), whereas BCM%BW was significantly lower in the LC group than in the M.CON group (50.9+/-4.6 vs. 54.4+/-7.1%, P=0.018). Furthermore, BCM%BW negatively correlated with the model for end-stage liver disease (MELD) score (P=0.04). In concluson, BCM showed a significant decrease and a negative correlation with the MELD score in the LC group. BCM may be a useful parameter for assessing malnutrition and severity of LC.