184 research outputs found
The human milk protein-lipid complex HAMLET disrupts glycolysis and induces death in Streptococcus pneumoniae
HAMLET is a complex of human a-lactalbumin (ALA) and oleic acid and kills several Gram-positive bacteria by a mechanism that bears resemblance to apoptosis in eukaryotic cells. To identify HAMLET's bacterial targets, here we used Streptococcus pneumoniae as a model organism and employed a proteomic approach that identified several potential candidates. Two of these targets were the glycolytic enzymes fructose bis-phosphate aldolase (FBPA) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Treatment of pneumococci with HAMLET immediately inhibited their ATP and lactate production, suggesting that HAMLET inhibits glycolysis. This observation was supported by experiments with recombinant bacterial enzymes, along with biochemical and bacterial viability assays, indicating that HAMLET's activity is partially inhibited by high glucose-mediated stimulation of glycolysis but enhanced in the presence of the glycolysis inhibitor 2-deoxyglucose. Both HAMLET and ALA bound directly to each glycolytic enzyme in solution and solid phase assays and effectively inhibited their enzymatic activities. In contrast, oleic acid alone had little to no inhibitory activity. However, ALA alone also exhibited no bactericidal activity and did not block glycolysis in whole cells, suggesting a role for the lipid moiety in the internalization of HAMLET into the bacterial cells to reach its target(s). This was verified by inhibition of enzyme activity in whole cells after HAMLET but not ALA exposure. The results of this study suggest that part of HAMLET's antibacterial activity relates to its ability to target and inhibit glycolytic enzymes, providing an example of a natural antimicrobial agent that specifically targets glycolysis
Diclofenac sodium ion exchange resin complex loaded melt cast films for sustained release ocular delivery
The goal of the present study is to develop polymeric matrix films loaded
with a combination of free diclofenac sodium (DFSfree) and DFS:Ion exchange
resin complexes (DFS:IR) for immediate and sustained release profiles,
respectively. Effect of ratio of DFS and IR on the DFS:IR complexation
efficiency was studied using batch processing. DFS:IR complex, DFSfree, or a
combination of DFSfree+DFS:IR loaded matrix films were prepared by melt-cast
technology. DFS content was 20% w/w in these matrix films. In vitro
transcorneal permeability from the film formulations were compared against DFS
solution, using a side-by-side diffusion apparatus, over a 6 h period. Ocular
disposition of DFS from the solution, films and corresponding suspensions were
evaluated in conscious New Zealand albino rabbits, 4 h and 8 h post-topical
administration. All in vivo studies were carried out as per the University of
Mississippi IACUC approved protocol. Complexation efficiency of DFS:IR was
found to be 99% with a 1:1 ratio of DFS:IR. DFS release from DFS:IR suspension
and the film were best-fit to a Higuchi model. In vitro transcorneal flux with
the DFSfree+DFS:IR(1:1)(1 + 1) was twice that of only DFS:IR(1:1) film. In
vivo, DFS solution and DFS:IR(1:1) suspension formulations were not able to
maintain therapeutic DFS levels in the aqueous humor (AH). Both DFSfree and
DFSfree+DFS:IR(1:1)(3 + 1) loaded matrix films were able to achieve and
maintain high DFS concentrations in the AH, but elimination of DFS from the
ocular tissues was much faster with the DFSfree formulation. DFSfree+DFS:IR
combination loaded matrix films were able to deliver and maintain therapeutic
DFS concentrations in the anterior ocular chamber for up to 8 h. Thus, free
drug/IR complex loaded matrix films could be a potential topical ocular
delivery platform for achieving immediate and sustained release
characteristics
Advancements In Effective Black Cotton Soil Stabilization: A Review
Soil stabilization has become the main concern to develop promising structures by strengthening the characteristics of weak soil. This can be achieved by incorporating many stabilization techniques like sand cushions, CNS layer method, columns, vibrations, and chemical methods. This re-view is based on a study of different soil stabilizing procedures and their effectiveness in altering and intensifying the features like Optimum Moisture Content (OMC), California Bearing Ratio (CBR), Maximum Dry Density (MDD), Unconfined Compressive Strength (UCS) and shrinkage behavior, etc., of feeble soil as it covers the greatest land area in India
OPTIMISATION OF IBUPROFEN FAST DISSOLVING TABLETS EMPLOYING STARCH XANTHATE USING 23 FACTORIAL DESIGN
Objective: To evaluate starch xanthate as a super disintegrant in the formulation of fast dissolving tablets of poorly soluble drugs employing 23 factorial design.Methods: Starch xanthate was synthesized by gelatinization process. The synthesized starch xanthate was subjected to physical and micromeritic evaluation. To establish as starch xanthate as a super disintegrant, fast dissolving tablet of ibuprofen was prepared employing starch xanthate in different proportions in each case by direct compression method employing 23 factorial design. All fast dissolving tablets prepared were evaluated for drug content, hardness, friability, disintegration time and other dissolution characteristics like percent dissolved in 5 min (PD5), Dissolution efficiency in 5 Min (DE5%) and first order rate constant(K1).Results: The starch xanthate prepared was found to be fine, free flowing slightly crystalline powder. Starch xanthate exhibited good swelling in water. Fourier transform infrared spectra (FTIR) and Differential scanning calorimetry (DSC) study indicated the absence of interaction between Ibuprofen and starch xanthate. All the fast dissolving tablets formulated employing starch xanthate were of good quality with regard to drug content(100±5%), hardness (3.6–4 kg/sq. cm), and friability (0.12-0.15%). The disintegration time of all the formulated tablets was found to be in the range of 13±0. 02 to 108±0.02s. The optimised formulation FL7 has the least disintegration time i.e., 13±0. 02s. The In vitro wetting time of the formulated tablets was found to be in the range of 90±0.15 to 369±0.17s. The In–Vitro wetting time was less (i.e., 90s) in optimized formulation FL7. The water absorption ratio of the formulated tablets was found to be in the range of 94±0.16 to 192±0.15%. The cumulative drug dissolved in the optimized formulation FL7 was found to be 99.63±0.24% in 5 min.Conclusion: Starch xanthate was found to be a super disintegrant which enhanced the dissolution efficiency when combined with sodium starch glycolate, croscarmellose sodium, with the ibuprofen and hence it could be used in the formulation of fast dissolving tablets to provide immediate release of the contained drug within 5 min
Rock Magnetic properties of Proterozoic mafic dykes from the Southern margin of Cuddapah Basin
Seventeen basic dykes of Proterozoic age intruding the Archaean basement from the Southern margin of the Cuddapah Basin were studied from five sites for their magnetic characters. NRM intensity (Jn) of the dykes range between 1793 and 57×10−3 Am−1 while magnetic susceptibility (χ) ranges from 31 to 303×10−6 CGS units. Koenigsberger's ratio (Qn) varies from 1 to 55 for most of the specimens. All the above parameters are indicative of retaining the original magnetization in most of the dykes sampled. Based on the above mentioned rock magnetic properties along with hysterisis studies and low temperature (−196°C) magnetic studies, it is inferred that the main magnetic carrier in these dykes is magnetite in multi domain and mixed domain states. Dykes from Tirupati area seems to be magnetically altered
A Prototype of Fingerprint and ZigBee Based Train Ignition System
Abstract. At present, number of vehicles is successfully implementing fingerprint system for authentic ignition. By this system unauthorized accessing of the train or mishandlings can be avoided. The Fingerprint and ZigBee based Train Ignition system can serve as a robust security mechanism and can avoid trains being driven by unauthorized person at any circumstances. Fingerprints are the most widely used form of biometric identification overtime and the critical step in exploring its advantages is to adopt it for use as a form of security in already existing systems, such as trains. This paper work focuses on the use of fingerprints for train ignition along with the conventional method of using keys. The fingerprint recognition software enables fingerprints of valid users of the train to be enrolled in a database. The developed prototype serves as an impetus to drive future research, geared towards developing a more robust and embedded real-time fingerprint based ignition systems in trains along with ZigBee communication
Fishery and Exploitation of Malabar Grouper, Epinephelus malabaricus (Bloch & Schneider 1801) from Andaman Islands
The fishery and population dynamics of groupers from Andaman Islands were studied from Jan 2010 to Dec
2011 with a special emphasis on Malabar grouper, Epinephelus malabaricus (Bloch & Schneider 1801). The average
annual catch of Malabar grouper was 1,296 tonnes contributing to 21.6% of annual grouper landings. Length-weight
relationship of Malabar grouper showed that growth was allometric (b=2.96) and relative condition factor (Kn) was 1
and the growth parameters viz., L∞, K and t0 were 124.60 cm, 0.80 and -0.05 respectively. The recruitment pattern was
unimodal with one major peak during April to July throughout the study period. The natural mortality (M), fishing
mortality (F) and total mortality (Z) were 1.05, 1.48 and 2.53 respectively and exploitation rate (E) was 0.58. The M/K
ratio (1.31) was found to be well within the normal range of 1to 2.5. Catch per unit effort varied from 4 to16.5 kg.h-1.
The maximum sustainable yield (MSY) was 1,107 tonnes which was lower than the average annual catch (1,296 tonnes),
indicating over exploitation. The current study calls for further research in identifying the grouper fishing and spawning
aggregation grounds and introduce measures for reducing fishing efforts with input and output controls to sustain the
Malabar grouper fishery in Andaman waters
Camera-port site metastasis of a renal-cell carcinoma after robot-assisted partial nephrectomy
Symbiotic brachyuran crab Eumedonus zebra Alcock, 1895 (Crustacea: Decapoda: Pilumnidae) – A first record from South east coast of India
1779-1781The article report the occurrence of the symbiotic brachyuran crab Eumedonus zebra Alcock, 1895 from Chennai, Tamil Nadu, south-eastern coast of India based on the morphometric characteristics of the species. This is the first record of genus Eumedonus from the region and is known to be an obligate symbionts of sea urchins
Strong Coupling of Localized Surface Plasmons to Excitons in Light-Harvesting Complexes
Gold nanostructure arrays exhibit surface plasmon resonances that split after attaching light harvesting complexes 1 and 2 (LH1 and LH2) from purple bacteria. The splitting is attributed to strong coupling between the localized surface plasmon resonances and excitons in the light-harvesting complexes. Wild-type and mutant LH1 and LH2 from Rhodobacter sphaeroides containing different carotenoids yield different splitting energies, demonstrating that the coupling mechanism is sensitive to the electronic states in the light harvesting complexes. Plasmon-exciton coupling models reveal different coupling strengths depending on the molecular organization and the protein coverage, consistent with strong coupling. Strong coupling was also observed for self-assembling polypeptide maquettes that contain only chlorins. However, it is not observed for monolayers of bacteriochlorophyll, indicating that strong plasmon-exciton coupling is sensitive to the specific presentation of the pigment molecules
- …