The effect of metyrapone on cytokinin ([8-14C]benzylaminopurine) metabolism in mature green tomato pericarp

Cytokinin, [8-14C]Benzylaminopurine, metabolism in tomato pericarp was followed during a 3 h period utilizing thin layer chromatography and visualization by fluorography. Fluorography indicated the formation of at least 7 metabolites during 3 h. Cytokinin metabolism was reduced by approximately 40% in 3 h by the presence of 250 microM metyrapone, an inhibitor of cytochrome P-450 related enzyme systems. In the presence of metyrapone, the number of radioactive metabolites on the thin layer plate was reduced from 7 to 4 and 2 of these were unique to the metyrapone-treated sample. These data suggest the initial step in benzylaminopurine metabolism in tomato pericarp may be mediated by a cytochrome P-450 related enzyme system which is altered in the presence of metyrapone.     

Oligomerization of the cytoplasmic fragment from the aspartate receptor of Escherichia coli.

We have observed that a 31-kDa cloned fragment from the Escherichia coli aspartate receptor exhibits a reversible monomer-oligomer reaction. The fragment, derived from the cytoplasmic region of the receptor (c-fragment), contains the signaling functions of the receptor. The wild-type and nine missense mutant fragments were analyzed. The latter were selected by the effect of the mutations on the signaling properties of the intact receptor, which induced either persistent smooth swimming or tumbling in bacteria [Mutoh, N., Oosawa, K., & Simon, M. I. (1986) J. Bacteriol. 167, 992-998]. In pH 7.0 buffer, the mutations caused five out of the six smooth mutant c-fragments to form oligomers, while neither the three tumble mutant nor wild-type fragments exhibited significant oligomer formation. At a lower pH (5.5), all of the fragments displayed some tendency to form oligomers. The equilibria between the monomer and the oligomers were monitored by gel permeation chromatography (GPC) which resolved two to three forms with apparent molecular weights between 110,000 and 270,000. The proportions of the different forms depended on concentration, indicating an association-dissociation reaction. Static light scattering (SLS) was used to demonstrate that the solution molecular mass of the wild-type c-fragment was 31 kDa and not 110 kDa as indicated by chromatography. One oligomer-forming c-fragment (S461L) eluted as the monomer and one other form, which was determined to be a dimer by SLS. The weight-average molecular weights, calculated from GPC data as a function of protein concentration, agreed well with the weight-average molecular weights obtained by SLS for this mutant.(ABSTRACT TRUNCATED AT 250 WORDS)     

Fabrication of Dense Non-Circular Nanomagnetic Device Arrays Using Self-Limiting Low-Energy Glow-Discharge Processing

We describe a low-energy glow-discharge process using reactive ion etching system that enables non-circular device patterns, such as squares or hexagons, to be formed from a precursor array of uniform circular openings in polymethyl methacrylate, PMMA, defined by electron beam lithography. This technique is of a particular interest for bit-patterned magnetic recording medium fabrication, where close packed square magnetic bits may improve its recording performance. The process and results of generating close packed square patterns by self-limiting low-energy glow-discharge are investigated. Dense magnetic arrays formed by electrochemical deposition of nickel over self-limiting formed molds are demonstrated.     

Idiopathic Fanconi syndrome with progressive renal failure: a case report and discussion

Fanconi syndrome is a complex of renal tubular dysfunctions defined by glycosuria without diabetes, aminoaciduria, phosphaturia, and renal tubular acidosis. It is often associated with hypokalemia, hypophosphatemia, and rickets or osteomalacia. Although it is usually found in the setting of other well-established non-renal diseases, Fanconi syndrome may present without identifiable etiology or association. Very infrequently a patient with idiopathic Fanconi syndrome will progress to chronic renal failure. This case report details the course of such a patient over the 20 years since his diagnosis and discusses the syndrome's genetic background, clinical features, putative pathophysiology, and therapeutic options, including transplantation.     

Projet Rosace : robot sécurisé d’assistance à la chirurgie endoscopique

This article presents work carried out as part of the robot sécurisé d’assistance à la chirurgie endoscopique (Rosace) project (funding ANR TecSan06), involving both academic and clinical partners along with an industrial partner in charge of technology integration. The main subject is a lightweight and compact robot for assistance in the endoscopic surgery field. The goal of the project has been to improve then transfer on a medical-grade product some technologies initially developed by the two academic partners. These technologies are: a first prototype of a robotic endoscope holder, an original method for visual servoing based on instrument tracking and some work done on comanipulation concept which consists in synergic interaction between robot and user. In accordance with the initial goals, major improvements have been obtained on these three aspects of the project. Robotic architecture improvement has contributed to enhance robot's versatility while robot command has been made more efficient and simple to use thanks to instrument tracking and comanipulation. After this 3-year project, initial prototype has turned into a commercially available product integrating (or that will integrate in a few months) these new technologies.     

The Insufficiency Intake of Dietary Micronutrients Associated with Malnutrition-Inflammation Score in Hemodialysis Population

The relations between dietary micronutrient, nutritional status and inflammation in hemodialysis patients are still unclear. A cross-sectional study was performed in hemodialysis population. 75 hemodialysis patients from South China participated in the dietary and nutritional assessment. Clinical and dietary data were collected. Nutritional status was assessed by Malnutrition-Inflammation Score (MIS) in addition to related anthropometric measurements. And according to the MIS score, the whole hemodialysis patients were divided into normal nutrition group and malnutrition group. The results showed that mid arm circumference (MAC) negatively correlated with MIS (r = −0.425; P = 0.002). The area under the ROC curve (AUC) for MAC was 0.737 (0.614–0.859). Comparing with the normal nutritional group, lower dietary selenium (Se), copper (Cu), iodine (I) and manganese (Mn) intake were observed among patients with malnutrition (P<0.05). While no significant differences of diverse vitamins were found. In conclusion, MAC was effective indicator for assessing nutritional and inflammatory status (P<0.05). The reduction of dietary Se, Cu, I and Mn intake level may be alarming markers for malnutrition and inflammatory status in hemodialysis patients.