Crystallization and evaluation of hen egg-white lysozyme crystals for protein pH titration in the crystalline state

Hen egg-white lysozyme was crystallized over a wide pH range (2.5–8.0) and the quality of the crystals was characterized. Crystallization phase diagrams at pH 2.5, 6.0 and 7.5 were determine

Structural and functional studies on Ycf12 (Psb30) and PsbZ-deletion mutants from a thermophilic cyanobacterium

Ycf12 (Psb30) and PsbZ are two low molecular weight subunits of photosystem II (PSII), with one and two trans-membrane helices, respectively. In order to study the functions of these two subunits from a structural point of view, we constructed deletion mutants lacking either Ycf12 or PsbZ from Thermosynechococcus elongatus, and purified, crystallized and analyzed the structure of PSII dimer from the two mutants. Our results showed that Ycf12 is located in the periphery of PSII, close to PsbK, PsbZ and PsbJ, and corresponded to the unassigned helix X1 reported previously, in agreement with the recent structure at 2.9 Å resolution (A. Guskov, J. Kern, A. Gabdulkhakov, M. Broser, A. Zouni, W. Saenger, Cyanobacterial photosystem II at 2.9 Å resolution: role of quinones, lipids, channels and chloride, Nat. Struct. Mol. Biol. 16 (2009) 334–342). On the other hand, crystals of PsbZ-deleted PSII showed a remarkably different unit cell constants from those of wild-type PSII, indicating a role of PsbZ in the interactions between PSII dimers within the crystal. This is the first example for a different arrangement of PSII dimers within the cyanobacterial PSII crystals. PSII dimers had a lower oxygen-evolving activity from both mutants than that from the wild type. In consistent with this, the relative content of PSII in the thylakoid membranes was lower in the two mutants than that in the wild type. These results suggested that deletion of both subunits affected the PSII activity, thereby destabilized PSII, leading to a decrease in the PSII content in vivo. While PsbZ was present in PSII purified from the Ycf12-deletion mutant, Ycf12 was present in crude PSII but absent in the finally purified PSII from the PsbZ-deletion mutant, indicating a preferential, stabilizing role of PsbZ for the binding of Ycf12 to PSII. These results were discussed in terms of the PSII crystal structure currently availabl

Roles of PsbI and PsbM in photosystem II dimer formation and stability studied by deletion mutagenesis and X-ray crystallography

PsbM and PsbI are two low molecular weight subunits of photosystem II (PSII), with PsbM being located in the center, and PsbI in the periphery, of the PSII dimer. In order to study the functions of these two subunits from a structural point of view, we crystallized and analyzed the crystal structure of PSII dimers from two mutants lacking either PsbM or PsbI. Our results confirmed the location of these two subunits in the current crystal structure, as well as their absence in the respective mutants. The relative contents of PSII dimers were found to be decreased in both mutants, with a concomitant increase in the amount of PSII monomers, suggesting a destabilization of PSII dimers in both of the mutants. On the other hand, the accumulation level of the overall PSII complexes in the two mutants was similar to that in the wild-type strain. Treatment of purified PSII dimers with lauryldimethylamine N-oxide at an elevated temperature preferentially disintegrated the dimers from the PsbM deletion mutant into monomers and CP43-less monomers, whereas no significant degradation of the dimers was observed from the PsbI deletion mutant. These results indicate that although both PsbM and PsbI are required for the efficient formation and stability of PSII dimers in vivo, they have different roles, namely, PsbM is required directly for the formation of dimers and its absence led to the instability of the dimers accumulated. On the other hand, PsbI is required in the assembly process of PSII dimers in vivo; once the dimers are formed, PsbI was no longer required for its stability

Mao-to Prolongs the Survival of and Reduces TNF-α Expression in Mice with Viral Myocarditis

Goal of this study was to evaluate effects of Mao-to on development of myocarditis induced by encephalomyocarditis (EMC) virus in mice. Mice were randomly divided into five groups. Group N included uninfected controls (n = 18), while group A, B and C underwent intraperitoneal injection of EMC virus. Group A was administered oral saline from day 0 to day 4. Group B was administered oral Mao-to (500 mg−1 kg−1 day−1) from day 0 to day 4. Group C was administered Mao-to from day 2 to day 6. Group D was administered Mao-to from day 5 to day 10. Treated mice were followed for survival rates during 2 weeks after infection. Body weight (BW) and organ weights including heart (HW), lungs, thymus and spleen were examined on days 4, 6 and 14. Survival rate of group C (36.4%) was significantly improved compared with group A, B or D (0% of each, P < 0.05). HW and HW/BW ratio in group C was significantly (P < 0.05) lower than those in group A, B or D. Viral titers of hearts were significantly different among groups A, B and C. Cardiac expression in tumor necrosis factor-α (TNF-α) was significantly reduced in group C in comparison with group A, B or D on day 6 by immunohistochemical study. Administration of Mao-to starting on day 2 improves mortality resulting from viral myocarditis in mice with reduced expression of cardiac TNF-α. These findings suggest that timing of Mao-to is crucial for preventing cardiac damage in mice with viral myocarditis

Comprehensive analysis including the nutritional point of view on the pathogenesis of periodontal disease

To clarify risk factors for periodontal disease from the viewpoints of physiology, blood biochemistry, and nutrition, a survey involving 364 persons (224 males, 140 females) who consulted the Medical Examination Center of Matsumoto Dental University Hospital was conducted. The pathogenesis of periodontal disease was investigated using the maximum Community Periodontal Index (CPI) and Attachment Loss (AL) values, and their distributions with respect to the sex were analyzed using Wilcoxonʼs rank sum test. Based on the CPI and AL values, the subjects were divided into 3 groups: healthy (0), mild (1–2), and severe (3–4). The mean values obtained from the physiological, dental, blood biochemical, and nutritional findings in the 3 groups were analyzed using the multiple comparison test. Furthermore, their distributions with respect to sex and smoking in the 3 groups were analyzed using Fisherʼs direct probability test. A p–value of 0.05 was regarded as significant. Factors influencing the CPI included the sex (male), body mass index (BMI), abdominal circumference, diastolic blood pressure, AL, alanine aminotransferase (ALT), fasting blood glucose, neutral fat, HDL cholesterol, and smoking. Factors influencing the AL included the sex (male), age, current number of teeth, CPI, lipid intake, manganese intake, vitamin C intake, monounsaturated fatty acid intake, polyunsaturated fatty acid intake, n–6 fatty acid intake, fruit intake, and smoking. The results suggest that the physiological, blood biochemical, and nutritional states are involved in the pathogenesis of periodontal disease. The CPI was associated with metabolic error in the presence of metabolic syndrome. There was an association between the AL and diet as an environmental factor

Factors related to the number of missing teeth from a physiological, blood biochemical, and nutritional point of view

The aim of this study was to clarify the risk factors for tooth loss from a physiological, blood biochemical, and nutritional point of view. The subjects of this study were 364 people (224 males, 140 females). They were examinees of a medical examination center in Matsumoto Dental University Hospital. Using the number of teeth present (including sound, decayed, and filled teeth) as the response variable, a multiple regression analysis was conducted using parameters in the mouth, physiological parameters, blood biochemical parameters, and nutritional parameters as covariates. In the multiple regression analysis with the response variable as the number of teeth present, the significant influence of attachment loss, sugar–sweetener intake, age, and sodium intake was noted on a decreasing number of teeth in the study subjects. Thus, the number of teeth present was influenced by the physiological, blood biochemical, and nutritional condition. In the future, increasing the number of cases will be necessary along with long–term follow–up

« Uluus ».The first médecine with a western-styled name in Japan / (« Uluus », Le premier médicament nommé à l'européenne au Japon)

Iwai Kojiro, Nojiri Kayoko, Aoki Nobuo. « Uluus ».The first médecine with a western-styled name in Japan / (« Uluus », Le premier médicament nommé à l'européenne au Japon). In: Revue d'histoire de la pharmacie, 84ᵉ année, n°312, 1996. Actes du XXXIe Congrès International d'Histoire de la Pharmacie (Paris, 25-29 septembre 1995) p. 378