Vitamin B6 Deficiency and Galactose Induced Alterations in Morphology and Osmotic Fragility of Rat Erythrocytes

Recently, red blood cells have been investigated mainly for alterations in ion transporting capacity, membrane bound enzymes or modifications in the structure of its individual constituents in clinical and experimental urolithiasis. However, the implication of such modifications on the physical state or morphology of cells has not been investigated. Scanning electron microscopic studies performed in vitamin B6 deficient and/or galactose fed rat (established hyperoxaluric models) erythrocytes, showed the presence of large number of stomatocytes, spherocytes and other variously deformed cells as compared to discocytic cells seen in normal control group. These changes in shape were in concurrence with red cell osmotic fragility, which decreased both in vitamin B6 deficient and vitamin B6 deficient + galactose fed group (19% and 33% hemolysis at 4 g/l NaCl, respectively) while it increased in galactose control group (73% hemolysis at 4 g/l NaCl) as compared to normal control group (55 % hemolysis at 4 g/l NaCl). These morphological and physical state alterations could be correlated with red blood cells\u27 membrane cholesterol and phospholipid sub-class distribution. These findings suggest that some structural membrane changes occur due to vitamin B6 deficiency and/or galactose feeding, which may be responsible for the altered membrane functions known to be associated with pathogenesis of urolithiasis

The thermal ignition problem in a cube

Steady state solutions for spontaneous thermal ignition in a unit cube are considered. For the unit sphere there are numerous solutions possible: these appear as ``wiggles'' in the bifurcation diagram. For the unit sphere this has been shown analytically. In contrast, for the unit cube analytic solutions are not possible and hence we must resort to numerical methods to determine the corresponding bifurcation diagram. Comparisons between the cube and the sphere are made

Mining substructures in protein data

In this paper we consider the 'Prions' database that describes protein instances stored for Human Prion Proteins. The Prions database can be viewed as a database of rooted ordered labeled subtrees. Mining frequent substructures from tree databases is an important task and it has gained a considerable amount of interest in areas such as XML mining, Bioinformatics, Web mining etc. This has given rise to the development of many tree mining algorithms which can aid in structural comparisons, association rule discovery and in general mining of tree structured knowledge representations. Previously we have developed the MB3 tree mining algorithm, which given a minimum support threshold, efficiently discovers all frequent embedded subtrees from a database of rooted ordered labeled subtrees. In this work we apply the algorithm to the Prions database in order to extract the frequently occurring patterns, which in this case are of induced subtree type. Obtaining the set of frequent induced subtrees from the Prions database can potentially reveal some useful knowledge. This aspect will be demonstrated by providing an analysis of the extracted frequent subtrees with respect to discovering interesting protein information. Furthermore, the minimum support threshold can be used as the controlling factor for answering specific queries posed on the Prions dataset. This approach is shown to be a viable technique for mining protein data

Combustion waves in a model with chain branching reaction and their stability

In this paper the travelling wave solutions in the adiabatic model with two-step chain branching reaction mechanism are investigated both numerically and analytically in the limit of equal diffusivity of reactant, radicals and heat. The properties of these solutions and their stability are investigated in detail. The behaviour of combustion waves are demonstrated to have similarities with the properties of nonadiabatic one-step combustion waves in that there is a residual amount of fuel left behind the travelling waves and the solutions can exhibit extinction. The difference between the nonadiabatic one-step and adiabatic two-step models is found in the behaviour of the combustion waves near the extinction condition. It is shown that the flame velocity drops down to zero and a standing combustion wave is formed as the extinction condition is reached. Prospects of further work are also discussed.Comment: pages 32, figures 2

Role of contrast-enhanced ultrasound (CEUS) in paediatric practice: an EFSUMB position statement

The use of contrast-enhanced ultrasound (CEUS) in adults is well established in many different areas, with a number of current applications deemed off-label, but the use supported by clinical experience and evidence. Paediatric CEUS is also an off-label application until recently with approval specifically for assessment of focal liver lesions. Nevertheless there is mounting evidence of the usefulness of CEUS in children in many areas, primarily as an imaging technique that reduces exposure to radiation, iodinated contrast medium and the patient-friendly circumstances of ultrasonography. This position statement of the European Federation of Societies in Ultrasound and Medicine (EFSUMB) assesses the current status of CEUS applications in children and makes suggestions for further development of this technique

Optimization of explants, media, plant growth regulators and carbohydrates on callus induction and plant regeneration in Citrus jambhiri Lush.

Callus induction was attempted from the four explants viz. root, cotyledon, epicotyl, and leaf segments excised from in vitro raised seedlings of C. jambhiri. Among various MS media supplementations with growth regulators and carbohydrates, the maximum (95.50%) and the earliest (8.30 days) callogenesis was obtained in epicotyl segments, when cultured on MS medium supplemented with NAA (10.0 mgl-1) + BAP (1.0 mgl-1) + sucrose (8%). The modified MS (macro and micro-nutrients reduced to half) fortified with BAP (5.0 mgl-1) + GA3 (3.0 mgl-1) recorded maximum shoot regeneration (43.10%) from callus, with an average of 5.30 shoots per callus after 35.50 days of culturing. However, prolonged exposure to GA3 resulted in thin elongated shoots and leaves. The age of the callus substantially influenced the plant regeneration frequency. The potency of the callus to regenerate decreased significantly with an increase in the age of the callus. Shoot regeneration was recorded maximum (43.43%) in 60 days old calli, followed by 90 days old (30.48%) calli, whereas it was minimum (10.46%) in 150 days old calli. The maximum (79.50%) shoot proliferation was recorded in MS medium supplemented with BAP (1.0 mgl-1) + Kin (0.5 mgl-1) with an average of 5.06 shoots per culture. The MS medium fortified with NAA (1.0 mgl-1) + IBA (1.0 mgl-1) induced maximum (77.33%) rooting, with an average of 3.19 roots per shoot after 13.4 days of culturing. Rooted plants were hardened and survived the best (83.6%) on the potting mixture consisting of cocopeat + vermiculite + perlite (2:1:1)

Gene delivery to in situ veins: Differential effects of adenovirus and adeno-associated viral vectors

AbstractPurpose: Gene transfer offers the potential to modify vein graft biology at the time of surgical implantation. Efficiency of gene delivery, stability of expression, and host responses are critical parameters for candidate vectors. We compared the effects of intraluminal exposure with adenovirus (AD) and adeno-associated virus (AAV) vectors on transgene expression and monocyte adhesion (MA) in treated vein segments. Methods: Adult New Zealand white rabbits (N = 51) were anesthetized, and the jugular veins were cannulated bilaterally. Veins were gently distended with either vector (2·108 to 1·1010 infective particles/mL) or vehicle (control) for 30 minutes, after which venous flow was restored. AD and AAV vectors encoding for the marker genes β-galactosidase (LacZ) and green fluorescent protein (GFP) were used. Vessels were explanted 2 to 40 days postinfection for analysis of gene expression (X-gal staining, reverse transcriptase-polymerase chain reaction), MA, and immunohistochemistry. Ex vivo adhesion assays used 51Cr-labeled THP-1 cells. Statistical significance was tested by using analysis of variance with a P value less than.05. Results: All animals survived, and all treated veins were patent at sacrifice. Intraluminal exposure to AD at a titer of 1·109 resulted in near complete transduction of the endothelium at 2 days, with no detectable expression by day 14. At an equal titer of infectious particles, transgene expression was markedly less for AAV at 2 to 7 days, but improved at 2 weeks and persisted to 40 days. MA was significantly increased 2 days after AD exposure (2.7-fold vs control, *P <.002); AAV treatment had no discernible effect on MA. Conclusion: AD-mediated gene transfer to vein segments resulted in robust, transient gene expression that disappeared after 2 weeks. In comparison, AAV-mediated gene delivery was less efficient, but resulted in delayed onset, persistent expression beyond 30 days. AD exposure induced an early increase in MA to the vein surface that was not seen with AAV treatment. Current generations of both AD and AAV vectors have significant, albeit different, limitations for vascular gene therapy. (J Vasc Surg 2000;31:1149-59.

Gas phase production of NHD2 in L134N

We show analytically that large abundances of NH2D and NHD2 can be produced by gas phase chemistry in the interiors of cold dense clouds. The calculated fractionation ratios are in good agreement with the values that have been previously determined in L134N and suggest that triply-deuterated ammonia could be detectable in dark clouds. Grain surface reactions may lead to similar NH2D and NHD2 enhancements but, we argue, are unlikely to contribute to the deuteration observed in L134N.Comment: 6 pages, 2 figures, uses psfig.sty and emulateapj.sty, to appear in Astrophysical Journal, vol 55

Numerical investigation of a reaction in a batch reactor: flammability limits

We study the spatial behaviour of the hydrogen-chlorine reaction in a batch reactor. The solutions exhibit regimes of slow and fast reaction. The main aim of this work is to distinguish between flaming and non-flaming mixtures from the numerical solutions. After setting out a practical criterion for flammability, we construct diagrams in parameter space which display the regions in which the reaction mixture is flammable