Basis for detection of stenosis using venous administration of microbubbles during myocardial contrast echocardiography: bolus or continuous infusion?

Recent studies have shown that the lactating mammary gland is able to utilize plasma-derived dipeptides for milk protein synthesis. However, it was not clear whether the peptides were hydrolysed followed by uptake of the constituent amino acids or were taken up intact. In view of this, we have designed experiments to investigate (a) whether the lactating rat mammary gland is capable of transporting hydrolysis-resistant dipeptides and (b) whether or not mammary cells are able to hydrolyse peptides, including glutathione, extracellularly. The uptake of the hydrolysis-resistant dipeptides D-[3H]Phe-L-Gln and D-[3H]Phe-L-Glu by the perfused rat mammary gland was low. Concomitant addition of L-Leu-L-Ala (50 mM) had no effect on the clearance of either labelled dipeptide suggesting that the small, albeit significant, uptake of the dipeptides is not via a high affinity peptide transporter (PepT1/PepT2). All anionic dipeptides tested (L-Glu-L-Ala, L-Asp-L-Ala, L-Ala-L-Asp, L-Asp-Gly, Gly-L-Asp and Gly-L-Glu) with the exception of D-Phe-L-Glu were able to trans-accelerate the efflux of labelled D-aspartate from preloaded rat mammary tissue (explants and perfused mammary gland). It appears that these peptides were being hydrolysed extracellularly followed by the uptake of free anionic amino acids via the mammary tissue high affinity, Na+-dependent anionic amino acid carrier operating in the exchange mode. Glutathione was able to trans-accelerate D-aspartate efflux from lactating rat mammary tissue in a fashion which was sensitive to the peptidase inhibitor acivicin. This suggests that gamma-glutamyltranspeptidase hydrolyses glutathione to produce L-glutamate which is subsequently transported via the high-affinity anionic amino acid carrier. Hydrolysis of peptides followed by uptake of the constituent amino acids may provide an important source of amino acids for milk protein synthesis.     

Prevalence of tuberculosis in Kishtwar Tehsil of Jammu region in Jammu and Kashmir State

A study of prevalence of tuberculosis in Kishtwar tehsil of Jammu region was conducted from June 1991 to May 1992. A total of one thousand two hundred ninety-eight rural as well as urban population suffering from various types of lung diseases was studied for prevalence of tuberculosis and a sizeable number (98) of patients were found to be positive of various types of tuberculosis, viz, pulmonary tuberculosis, tuberculous pleural effusion and miliary tuberculosis. Of the population studied 7.55% were found to be positive for tuberculosis and among them 88.76% patients were anaemic and the commonest type of anaemia was normocytic normochromic and normocytic hypochromic. The ESR was raised in almost of all the patients. Of the population, 80.61% were seen to be positive on skiagram chest and 58.16% were found to be positive on other diagnostic tests like Mantoux's tests, sputum for acid-fast bacilli, etc. Mantoux's test was positive in 27.55% cases and sputum was positive in 30.61% cases. All the cases studied were subjected to special investigations. The changes in parameters are consistent with the diagnosis of tuberculosis. Large family size, poverty, excessive smoking, illiteracy, etc, are the major contributing factors.     

Power-driven challenges in nanometer design

Addressing fundamental challenges to designing high-performance ICs in nanometer-scale technologies, the authors advocate a flexible approach to limiting both dynamic and static power. They recommend global-signaling strategies to curb communication power requirements and thermal management techniques to ease the burden on packaging     

The role of oxidative stress in rhinovirus induced elaboration of IL-8 by respiratory epithelial cells

A direct correlation has been reported between the severity of symptoms associated with rhinovirus infection and the concentration of interleukin-8 in nasal secretions. The purpose of these studies was to examine the mechanism of rhinovirus-induced IL-8 elaboration. Rhinovirus infection induced oxidative stress in Beas-2b cells and the concentration of H2O2 in supernatant media from rhinovirus challenged cells was 12.5 +/- 6.1 microM 1 h after challenge compared to 0.7 +/- 0.3 microM in supernatant from control cells. N-acetyl cysteine inhibited RV-induced NF-kappaB activation and IL-8 elaboration. IL-8 concentrations were 36 +/- 2 pg/ml and 10 +/- 1 pg/ml 6 h after virus challenge in untreated and NAC-treated (30 mM NAC) cells, respectively. Despite the effects of NAC on IL-8 elaboration and NF-kappaB activation, RV stimulated increases in supernatant H2O2 were not altered by NAC. These data suggest that RV stimulation of IL-8 in respiratory epithelium is mediated through production of oxidative species and the subsequent activation of NF-kappaB.     

Secondary organic aerosol: a comparison between foggy and nonfoggy days

Carbonaceous species, meteorological parameters, trace gases, and fogwater chemistry were measured during winter in the Indian city of Kanpur to study secondary organic aerosol (SOA) during foggy and clear (nonfoggy) days. Enhanced SOA production was observed during fog episodes. It is hypothesized that aqueous phase chemistry in fog drops is responsible for increasing SOA production. SOA concentrations on foggy days exceeded those on clear days at all times of day; peak foggy day SOA concentrations were observed in the evening vs peak clear day SOA concentrations which occurred in the afternoon. Changes in biomass burning emissions on foggy days were examined because of their potential to confound estimates of SOA production based on analysis of organic to elemental carbon (OC/EC) ratios. No evidence of biomass burning influence on SOA during foggy days was found. Enhanced oxidation of SO(2) to sulfate during foggy days was observed, possibly causing the regional aerosol to become more acidic. No evidence was found in this study, either, for effects of temperature or relative humidity on SOA production. In addition to SOA production, fogs can also play an important role in cleaning the atmosphere of carbonaceous aerosols. Preferential scavenging of water-soluble organic carbon (WSOC) by fog droplets was observed. OC was found to be enriched in smaller droplets, limiting the rate of OC deposition by droplet sedimentation. Lower EC concentrations were observed on foggy days, despite greater stagnation and lower mixing heights, suggesting fog scavenging and removal of EC was active as well.     

Nutritional potential, bioaccessibility of minerals and functionality of watermelon (Citrullus vulgaris) seeds

Watermelon (Citrullus vulgaris) seeds are high in protein and fat, on enriching protein, it can find application as a protein source in various food formulations. Most of the processed foods are generally fortified with micronutrients. The effect of the matrix on the mineral bioavailability is highly important and hence investigated. Defatted flour and protein isolate were prepared from watermelon seed meal and chemical composition and functionality was analyzed by standard techniques. Multiple regression analysis was done to study the compositional influence on the mineral bioaccessibility. Invitro digestibility of the protein was good. The seeds were a moderate source of iron and zinc. The percent bioaccessibility of all the minerals were found to correlate (R = 0.97-0.99) with the concentration of phytate, tannin and oxalate contents. The seed components exhibited good functionality with good macro and micronutrient density and can find application in many food products.     

Counselor race and power base: Effects on attitudes and behavior.

Assessed the effects of expert and referent power bases and counselor race on Ss' attitude and behavior change. 32 White undergraduates who identified themselves as having procrastination and career-planning problems were divided into internal or external groups on the basis of their scores on Rotter's Internal–External Locus of Control Scale. Four female interviewers, 2 Black and 2 White, portrayed either an expert or referent role and attempted to influence Ss to use a problem-solving process and perform a career-planning activity. Dependent variables included a measure of attitude change, a measure assessing knowledge of the problem-solving process, and 2 behavioral measures. Results show that (a) the roles were perceived as intended, (b) Ss of expert interviewers recalled more of the problem-solving process, and (c) significant interactions of race and role were obtained such that Black-expert and White-referent interviewers were most influential both in attitude and behavior change. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mach-Zehnder interference microscopy optically records electrically stimulated cellular activity in unstained nerve cells

Dual-beam white light interference microscopy monitors changes in the optical density of the investigated object with high sensitivity. We report on the recording of dynamic changes in a neuron's optical density evoked by extracellular electrical stimulation. These recorded changes were analysed and unambiguously connected to the investigated object, an invertebrate neuron of the pond snail Lymnaea stagnalis. The results provide evidence for the method's applicability in visualizing cellular dynamics purely by evaluating changes in a cell's optical properties.