Studies on energy transformation in the freshwater snail Pila globosa 1. Influence of feeding rate

The effects of eleven chosen feeding levels ranging from 0 to 198 mg damp dry (plant) Ceratophyllumlg live snail /day on the absorption, conversion and metabolism of the snail Pi/a globosa (of 1•9 g body weight) have been studied. Absorption rates increased from 3•0 to 21•0 mg dry food /g live snail/day in snails fed 3-4-28'8 mg dry food/ g live snail/day. In these snails, absorption efficiency decreased from 87•5 to 73•0 %

Anomalous cooling of the parallel velocity in seeded beams

We have measured the parallel velocity distribution of a lithium supersonic beam produced by seeding lithium in argon. The parallel temperature for lithium is considerably lower than the calculated parallel temperature of the argon carrier gas. We have extended the theory of supersonic cooling to calculate the parallel temperature of the seeded gas, in the limit of high dilution. The theoretical result thus obtained is in good agreement with ourobservations.Comment: 01 june 200

Effects of candesartan versus amlodipine on capillary rarefaction, pulse wave velocity, and central blood pressure in patients with essential hypertension

Background: A reduction in the density of capillaries (rarefaction) is known to occur in many tissues in patients with essential hypertension and play a role in increasing Blood Pressure (BP). The aim of this trial was to assess in a randomized, double blind, design the effects of treatment of hypertension with candesartan versus amlodipine on microvascular rarefaction and other indices of vascular function. Methods: We recruited twenty-two individuals with mild-to-moderate hypertension. After a 2-week placebo run-in period, patients who remained hypertensive (≥140/90 mmHg) were randomized to 8-weeks treatment with Candesartan tablets 8mg daily (with forced titration to 16mg) or Amlodipine tablets 5mg daily (with forced titration to 10mg). The capillary microcirculation was studied using CapiScope system CAM1. Pulse wave velocity, central BP and aortic Augmentation Index were also measured. Results: We observed significant reductions in brachial BP, and central BP after 4 and 8 weeks treatment with either candesartan or amlodipine but there was no significant effect on basal (functional) or maximal (structural) capillary densities, or pulse wave velocity. Conclusion: Eight weeks treatment of hypertension with either amlodipine or candesartan significantly reduced brachial and central BP but was not sufficient to induce a regression in functional or structural microvascular abnormalities

A Novel Method to Monitor Sequential Displacement of Capped Ligands in Gold Nanoparticles [abstract]

Nanoscience Poster SessionNanochemistry of ligand displacement reactions has attracted much attention in recent years for the development of myriad of new gold nanomaterials. Gold nanoparticles have shown applications ranging from tumor imaging agent in nanomedicine to single electron devices in information technology. New gold materials are synthesized by exchange of neutral or anionic ligands with thiolated molecules. Completion of ligand substitution reactions in gold nanoparticles are monitored by using UV-Vis spectrometry. However, there are no methods available to monitor the sequence of the ligand substitution reactions. Monitoring and predicting the sequence of ligand substitutions would provide a convenient handle for the design and development of hybrid nanomaterials containing two or more ligands. In this context, we have developed a novel technique utilizing disc centrifuge systems to monitor the sequential displacement of ligands in various gold nanoconstructs. In our studies, we have used gold nanoparticles stabilized with both anionic and neutral ligands. Gold nanoparticles of various different substitutions have been identified and characterized by disc centrifuge systems. Details of substitution reactions and mechanism on monitoring the sequential displacement using strong ligands will be presented

Agarose-stabilized gold nanoparticles for surface-enhanced Raman spectroscopic detection of DNA nucleosides

doi:10.1063/1.2192573 http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=APPLAB000088000015153114000001&idtype=cvips&prog=normal&doi=10.1063/1.2192573We present surface-enhanced Raman scattering (SERS) studies of DNA nucleosides using biologically benign agarose-stabilized gold nanoparticles (AAuNP). We compare the SERS activity of nucleosides with AAuNP to that of commercially obtained citrate-stabilized gold nanoparticles and find the SERS activity to be an order of magnitude higher with AAuNP. The higher SERS activity is explained in terms of the agarose matrix, which provides pathways for the gold nanoparticles to have distinct arrangements that result in stronger internal plasmon resonances.This work was supported through the University of Missouri Research Board grants URB04-023 (S.G.) and URB03-080 (M.C. and K.V.K.), NSF under Grant No. DMR-0413601and the NCI under Grant No. IR0ICA119412-01. The gold nanoparticles were produced and supplied by the University of Missouri Nanoparticle Production Core Facility

Green nanotechnology from cumin phytochemicals : generation of biocompatible gold nanoparticles

Published in final edited form as: Int J Green Nanotechnol Biomed. 2009 January 1; 1(1): B39-B52. doi:10.1080/19430850902931599.The powerful antioxidant characteristics of various phytochernicals within cumin prompted us to test their efficacy in reducing sodium tetrachloroaurate to corresponding gold nanoparticles. We, herein, report an unprecedented synthetic route that involves the production of well-defined spherical gold nanoparticles by simple mixing of cumin to an aqueous solution of sodium tetrachloro aurate. Production of gold nanoparticles in this cumin-mediated Green Nanotechnological process is achieved under biologically benign conditions. The gold nanoparticles generated through cumin-mediated process did not aggregate suggesting that the cocktail of phytochemicals including proteins serve as excellent coatings on nanoparticles and thus, provide robust shielding from aggregations. In addition, the phytochemical coatings on nanoparticles have rendered nontoxic features to these 'Green Gold Nanoparticles' as demonstrated through detailed MTT assays performed on 'normal fibroblast cells. Results of our studies presenting a new 'Nano-Naturo' connection for the production and utility of gold nanoparticles for potential applications in nanomedicine and nanotechnology are discussed in this paper.This work has been supported by the generous support from the National Institutes of Health/National Cancer Institute under the Cancer Nanotechnology Platform program (grant number: 5R01CA119412-01), NIH - 1R21CA128460-01 and University of Missouri-Research Board - Program C8761 RB 06-030

Integrating microfluidic generation, handling and analysis of biomimetic giant unilamellar vesicles

The key roles played by phospholipids in many cellular processes, has led to the development of model systems, to explore both lipid–lipid and lipid–peptide interactions. Biomimetic giant unilamellar vesicles represent close facsimiles of in vivo cellular membranes, although currently their widespread use in research is hindered by difficulties involving their integration into high-throughput techniques, for exploring membrane biology intensively in situ. This paper presents an integrated microfluidic device for the production, manipulation and high-throughput analysis of giant unilamellar vesicles. Its utility is demonstrated by exploring the lipid interaction dynamics of the pore-forming antimicrobial peptide melittin, assessed through the release of fluorescent dyes from within biomimetic vesicles, with membrane compositions similar to mammalian plasma membranes

Early Life Microcirculatory Plasticity and Blood Pressure Changes in Low Birth Weight Infants Born to Normotensive Mothers: A Cohort Study.

BACKGROUND: Capillary rarefaction (CR) is an established hallmark of essential hypertension (EH). The aim of this study was to examine early changes in capillary density (CD) and blood pressure (BP) in low birth weight (LBW) infants who are at risk of developing EH in later life. METHODS: We studied 77 LBW infants and 284 normal birth weight (NBW) infants, all born to mothers with normotension, in a longitudinal multicenter study. Intravital capillaroscopy was used to measure functional basal capillary density (BCD) and maximal capillary density (MCD) at birth, 3, 6, and 12 months. RESULTS: We found that LBW infants, born preterm and at term, had a significantly higher CD at birth, then underwent significant CR in the 1st 3 months culminating in a CD similar to that seen in NBW infants. NBW infants showed a gradual reduction in CD between birth and 12 months. Non-Caucasian ethnicity and preterm birth were significant predictors of a higher CD at birth. Systolic BP in NBW infants increased significantly from birth to 3 months, and we identified a significant negative correlation between systolic BP and MCD. CONCLUSIONS: This study has identified a process of early "accelerated capillary remodeling" in LBW infants, which corrects their higher CD at birth. This remodeling is unlikely to explain the CR seen in adult individuals with, or at risk of developing EH. Further follow-up studies are required to determine the timing and mechanisms involved in CR, which is likely to occur after the 1st year of life but before early adulthood