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1.  Higher Caspase-like activity in symptomatic isolates of Blastocystis spp 
Parasites & Vectors  2014;7:219.
Background
Biochemical evidence of a caspase-like execution pathway has been demonstrated in a variety of protozoan parasites, including Blastocystis spp. The distinct differences in the phenotypic characterization reported previously have prompted us to compare the rate of apoptosis in Blastocystis spp. isolated from individuals who were symptomatic and asymptomatic. In the current study, we analysed the caspase activation involved in PCD mediated by a cytotoxic drug, (metronidazole) in both symptomatic & asymptomatic isolates.
Methods
Apoptosis was induced in Blastocystis spp. by treating cultures of symptomatic and asymptomatic isolates of 3 sub-types namely 1, 3 and 5 with two different concentrations, 0.1 and 0.0001 mg/ml of metronidazole (with and without pre-treatment with a pan-caspase inhibitor, zVAD.fmk). The experiment was repeated to assess the number of apoptotic cells in all the isolates of both conditions.
Results
Symptomatic isolates of subtype 3 (without pre-treatment with a pan-caspase inhibitor, zVAD.fmk) showed high fluorescence intensity for active caspase-like proteases [0.0001 mg/ml, 88% (p < 0.001) at 0.1 mg/ml, 70% (p < 0.001)] at the 72nd hour in vitro culture in comparison with asymptomatic isolates [0.0001 mg/ml, 65%, at 0.1 mg/ml, 55%]. The number of apoptotic cells was higher [0.0001 mg/ml, 89% (p < 0.001) and at 0.1 mg/ml, 70% (p < 0.001)] at the 72nd hour of in vitro culture in comparison with asymptomatic isolates [0.0001 mg/ml, 66% (p < 0.001) and at 0.1 mg/ml, 45% (p < 0.01)]. Cells treated with metronidazole in the presence of zVAD.fmk showed less than 10% caspase activation.
Conclusion
The high number of symptomatic cells expressing active caspase-like proteases and becoming apoptotic compared to asymptomatic cells clearly demonstrates that the response to metronidazole treatment is isolate dependent. Hence this justifies the conflicting reports on the curative success rates when treated with this drug. The study has also created a need to identify apoptosis effectors in Blastocystis spp of different isolates especially as it was shown that apoptosis was sub-typed related. These findings can be exploited for the development of diagnostic markers and novel therapeutic drugs to enhance the effectiveness of the diagnosis and treatment of the patients infected with Blastocystis spp.
doi:10.1186/1756-3305-7-219
PMCID: PMC4049410  PMID: 24886677
Blastocystis spp; Apoptosis; Symptomatic; Asymptomatic; Caspase-like proteases; Programmed cell death; Metronidazole
2.  Solid-State Characterization and Dissolution Properties of Meloxicam–Moringa Coagulant–PVP Ternary Solid Dispersions 
AAPS PharmSciTech  2013;14(2):569-577.
The effect of ternary solid dispersions of poor water-soluble NSAID meloxicam with moringa coagulant (obtained by salt extraction of moringa seeds) and polyvinylpyrrolidone on the in vitro dissolution properties has been investigated. Binary (meloxicam–moringa and meloxicam–polyvinylpyrrolidone (PVP)) and ternary (meloxicam–moringa–PVP) systems were prepared by physical kneading and ball milling and characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffractometry. The in vitro dissolution behavior of meloxicam from the different products was evaluated by means of United States Pharmacopeia type II dissolution apparatus. The results of solid-state studies indicated the presence of strong interactions between meloxicam, moringa, and PVP which were of totally amorphous nature. All ternary combinations were significantly more effective than the corresponding binary systems in improving the dissolution rate of meloxicam. The best performance in this respect was given by the ternary combination employing meloxicam–moringa–PVP ratio of [1:(3:1)] prepared by ball milling, with about six times increase in percent dissolution rate, whereas meloxicam–moringa (1:3) and meloxicam–PVP (1:4) prepared by ball milling improved dissolution of meloxicam by almost 3- and 2.5-folds, respectively. The achieved excellent dissolution enhancement of meloxicam in the ternary systems was attributed to the combined effects of impartation of hydrophilic characteristic by PVP, as well as to the synergistic interaction between moringa and PVP.
doi:10.1208/s12249-013-9941-5
PMCID: PMC3665984  PMID: 23483432
amorphization; moringa coagulant; solubility enhancement; synergism; ternary solid dispersions
3.  Calcium Binding-Mediated Sustained Release of Minocycline from Hydrophilic Multilayer Coatings Targeting Infection and Inflammation 
PLoS ONE  2014;9(1):e84360.
Infection and inflammation are common complications that seriously affect the functionality and longevity of implanted medical implants. Systemic administration of antibiotics and anti-inflammatory drugs often cannot achieve sufficient local concentration to be effective, and elicits serious side effects. Local delivery of therapeutics from drug-eluting coatings presents a promising solution. However, hydrophobic and thick coatings are commonly used to ensure sufficient drug loading and sustained release, which may limit tissue integration and tissue device communications. A calcium-mediated drug delivery mechanism was developed and characterized in this study. This novel mechanism allows controlled, sustained release of minocycline, an effective antibiotic and anti-inflammatory drug, from nanoscale thin hydrophilic polyelectrolyte multilayers for over 35 days at physiologically relevant concentrations. pH-responsive minocycline release was observed as the chelation between minocycline and Ca2+ is less stable at acidic pH, enabling ‘smart’ drug delivery in response to infection and/or inflammation-induced tissue acidosis. The release kinetics of minocycline can be controlled by varying initial loading, Ca2+ concentration, and Ca2+ incorporation into different layers, enabling facile development of implant coatings with versatile release kinetics. This drug delivery platform can potentially be used for releasing any drug that has high Ca2+ binding affinity, enabling its use in a variety of biomedical applications.
doi:10.1371/journal.pone.0084360
PMCID: PMC3883660  PMID: 24409292
4.  Clinical Profile of Patients Admitted with Swine-Origin Influenza A (H1N1) Virus Infection: An Experience from A Tertiary Care Hospital 
Background: Pandemic influenza A (H1N1) 2009 has posed a serious public health challenge world-wide. H1N1 critical illness mostly affects young patients and is often fatal.
Objective: Primary objective was to study clinical profile of the patients admitted with confirmed H1N1 swine flu infection. Secondary objective was to observe the risk factors associated with complications like need of mechanical ventilation and or death among H1N1 infected patients.
Material and Methods: A prospective observational study was conducted in a tertiary care teaching hospital from June 2009, to December, 2011. H1N1 infection was confirmed by reverse transcriptase PCR. Statistical analysis was done by SPSS, version 11. Binary logistic regression was used to find out independent risk factors for morbidity.
Results: Total 495 patients were tested for H1N1 infection. Among them, 115 (23%) were positive and 88(76%) required admission. Median age of cohort was 29 years and 87% of the patients were below 54 years of age. Most common presenting symptoms were fever (98%), followed by cough (86%) and sore throat (54%). Out of 88 patients, 14 (16%) required mechanical ventilation and 6(6.8%) died. Lymphopaenia (Lymphocytes <10%) and presence of patchy infiltrates on chest X-ray (CXR) the time of presentation were independent risk factors associated with need of mechanical ventilation or death in H1N1 infected patients by multivariate analysis.
Conclusion: Present study showed that H1N1 swine flu mainly affected people who were < 54 years of age. Majority of patients improved with antiviral treatment. Lymphopaenia and CXR which showed bilateral pneumonia at time of presentation were found to be independent risk factors associated with requirement of mechanical ventilation and/or death in H1N1 infection. Pregnant females with flu constituted 33% of total mortality. High priority should be given to such patients. Further community based studies are required to analyze the actual impact of H1N1 infection in the community.
doi:10.7860/JCDR/2013/5657.3477
PMCID: PMC3843408  PMID: 24298482
H1N1; swine flu; lymphopaenia; bilateral pneumonia
5.  Analysis of the Mechanisms That Underlie Absorption of Botulinum Toxin by the Inhalation Route 
Infection and Immunity  2012;80(12):4133-4142.
Botulinum toxin is a highly potent oral and inhalation poison, which means that the toxin must have an efficient mechanism for penetration of epithelial barriers. To date, three models for toxin passage across epithelial barriers have been proposed: (i) the toxin itself undergoes binding and transcytosis; (ii) an auxiliary protein, HA35, transports toxin from the apical to the basal side of epithelial cells; and (iii) an auxiliary protein, HA35, acts on the basal side of epithelial cells to disrupt tight junctions, and this permits paracellular flux of toxin. These models were evaluated by studying toxin absorption following inhalation exposure in mice. Three types of experiments were conducted. In the first, the potency of pure neurotoxin was compared with that of progenitor toxin complex, which contains HA35. The results showed that the rate and extent of toxin absorption, as well as the potency of absorbed toxin, did not depend upon, nor were they enhanced by, the presence of HA35. In the second type of experiment, the potencies of pure neurotoxin and progenitor toxin complex were compared in the absence or presence of antibodies on the apical side of epithelial cells. Antibodies directed against the neurotoxin protected against challenge, but antibodies against HA35 did not. In the final type of experiment, the potency of pure neurotoxin and toxin complex was compared in animals pretreated to deliver antibodies to the basal side of epithelial cells. Once again, antibodies directed against the neurotoxin provided resistance to challenge, but antibodies directed against HA35 did not. Taken collectively, the data indicate that the toxin by itself is capable of crossing epithelial barriers. The data do not support any hypothesis in which HA35 is essential for toxin penetration of epithelial barriers.
doi:10.1128/IAI.00669-12
PMCID: PMC3497405  PMID: 22966044
6.  Reversible cerebellar ataxia with thyrotoxicosis: An autoimmune brain disease in remission due to Graves’ disease 
We hereby report a patient with seizure disorder who was on long term carbamazepine, admitted with features of thyrotoxicosis and cerebellar dysfunction. Anticonvulsant medications are cerebellar toxins; but in this case, reversal of cerebellar dysfunction was noted upon treatment of thyrotoxicosis with antithyroid drugs.
doi:10.4103/2230-8210.111675
PMCID: PMC3712388  PMID: 23869314
Ataxia; autoimmune; encephalopathy; thyrotoxicosis
7.  Mapping the Pattern and Trends of Extrapulmonary Tuberculosis 
Background and Objectives:
There has been a rapid expansion of the directly observed treatment short-term (DOTS) under the revised national tuberculosis control program throughout India in the last decade. Few reports exist detailing individual DOTS centers’ experiences with regard to extrapulmonary tuberculosis (EPTB) in a medical college hospital setting.
Materials and Methods:
This is a retrospective, record-based study of patients with the diagnosis of EPTB, in all age groups. Data on all consecutive EPTB cases diagnosed at the K. S. Hegde Medical College and Hospital, Deralakatte, Mangalore from 1 January 2005 to 31 December 2011 at the DOTS centre attached to this hospital were collected, analyzed by Mantel-Haenszel Chi square for linear trend and described in proportion or percentages.
Results:
Among 1267 cases registered for treatment of all forms of tuberculosis, 528 (41.67%) had EPTB. Around half of the cases of EPTB (269, 51%) were among adult age groups and the majority of cases (342, 64.77%) received Category-I treatment. Pleural TB was the commonest type of EPTB (n = 148, 28.03%), followed by lymph node TB (n = 131, 24.81%). Involvement of lymph nodes was the commonest manifestation among the less than 14 years’ age group (27, 58.7%), while involvement of pleura was more common among > 65 years’ age group (23, 45.1%). The difference in the occurrence of EPTB by site between males and females is statistically significant with a P value of <0.005. There is a significant increase in the number of cases of tuberculosis affecting bones and joints, and other forms of tuberculosis over the years.
Conclusion:
The burden of EPTB is more among the productive age group. Increase in the trend of bone and joint tuberculosis, and other rare forms of EPTB is a point of concern highlighting the importance of strengthening the services towards this group.
doi:10.4103/0974-777X.112277
PMCID: PMC3703211  PMID: 23853432
Directly observed treatment short-course; Extrapulmonary tuberculosis; India; Revised national tuberculosis control program
8.  8-Bromo-3-phenyl-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-carbo­nitrile 
In the title compound, C17H11BrN2O2, the five-membered isoxazole ring has an envelope conformation with the C atom bearing the phenyl ring as the flap. The pyran ring has a half-chair conformation. In the chromeno ring system, the dihedral angle between the mean plane of the pyran ring and the benzene ring is 4.68 (2)°. The dihedral angle between the mean planes of the chromeno ring system and the isoxazole ring is 13.79 (15)°. The latter forms a dihedral angle of 34.10 (17)° with the phenyl ring. In the crystal, mol­ecules are linked by C—H⋯N hydrogen bonds, forming an undulating two-dimensional network parallel to the ab plane.
doi:10.1107/S1600536813002511
PMCID: PMC3569831  PMID: 23424577
9.  Methyl 6-eth­oxy-3-phenyl-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-car­boxylate 
In the title compound, C20H19NO5, the dihedral angle between the mean plane of the pyran ring (which has a half-chair conformation) and the benzene ring of the chromeno ring system is 7.21 (7)°. The dihedral angle between the mean plane of the chromeno ring system and the isoxazole ring is 21.78 (6)°, while the isoxazole ring forms a dihedral angle of 72.60 (8)° with the attached phenyl ring. In the crystal, mol­ecules are linked via pairs of C—H⋯O hydrogen bonds, forming inversion dimers with an R 2 2(10) ring motif. These dimers are linked via C—H⋯N hydrogen bonds, forming chains along [001].
doi:10.1107/S1600536812051720
PMCID: PMC3569242  PMID: 23424465
10.  3-(2-Methyl­phen­yl)-3a,4-dihydro-3H-chromeno[4,3-c]isoxazole-3a-carbo­nitrile 
In the title compound, C18H14N2O2, the pyran ring of the chromeno ring system has a half-chair conformation, and the dihedral angle between its mean plane and the benzene ring is 5.3 (2)°. The isoxazole ring forms a dihedral angle of 74.6 (2)° with the attached benzene ring and is inclined to the mean plane of the chromeno ring system by 15.06 (19)°. In the crystal, there are no significant inter­molecular inter­actions.
doi:10.1107/S1600536812051732
PMCID: PMC3569243  PMID: 23424466
11.  Diethyl [(2-chloro­anilino)(1,3-diphenyl-1H-pyrazol-4-yl)meth­yl]phospho­nate 
In the title compound, C26H27ClN3O3P, the mean plane of the central pyrazole ring forms a dihedral angle of 71.37 (14)° with the chloro­phenyl ring. In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers with R 2 2(10) ring motifs. The 3-phenyl ring is disordered with four C atoms occupying two sets of sites with an occupancy ratio of 0.748 (4):0.252 (4).
doi:10.1107/S1600536812051719
PMCID: PMC3569244  PMID: 23424467
12.  Stage one Norwood procedure in an emerging economy:Initial experience in a single center 
Objective:
The evolution of surgical skills and advances in pediatric cardiac intensive care has resulted in Norwood procedure being increasingly performed in emerging economies. We reviewed the feasibility and logistics of performing stage one Norwood operation in a limited-resource environment based on a retrospective analysis of patients who underwent this procedure in our institution.
Methods:
Retrospective review of medical records of seven neonates who underwent Norwood procedure at our institute from October 2010 to August 2012.
Results:
The median age at surgery was 9 days (range 5-16 days). All cases were done under deep hypothermic cardiopulmonary bypass and selective antegrade cerebral perfusion. The median cardiopulmonary bypass (CPB) time was 240 min (range 193-439 min) and aortic cross-clamp time was 130 min (range 99-159 min). A modified Blalock-Taussig (BT) shunt was used to provide pulmonary blood flow in all cases. There were two deaths, one in the early postoperative period. The median duration of mechanical ventilation was 117 h (range 71-243 h) and the median intensive care unit (ICU) stay was 12 days (range 5-16 days). Median hospital stay was 30.5 days (range 10-36 days). Blood stream sepsis was reported in four patients. Two patients had preoperative sepsis. One patient required laparotomy for intestinal obstruction.
Conclusions:
Stage one Norwood is feasible in a limited-resource environment if supported by a dedicated postoperative intensive care and protocolized nursing management. Preoperative optimization and prevention of infections are major challenges in addition to preventing early circulatory collapse.
doi:10.4103/0974-2069.107225
PMCID: PMC3634250  PMID: 23626427
Emerging economy; Norwood procedure; pediatric cardiac intensive care
13.  2,2′-Diisopropoxy-5,5′-methyl­enedi­benz­alde­hyde 
Mol­ecules of the title compound, C21H24O4, are located on a twofold rotation axis running through the central methyl­ene C atom. The aldehyde group is coplanar with the benzene ring [C—C—C—O = 175.7 (4) °].
doi:10.1107/S1600536812028048
PMCID: PMC3393997  PMID: 22798862
14.  Diethyl [(2-bromo­anilino)(1,3-diphenyl-1H-pyrazol-4-yl)meth­yl]phospho­nate 
In the title compound, C26H27BrN3O3P, the central pyrazole ring forms a dihedral angle of 71.7 (2)° with the bromo­phenyl ring. In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers with R 2 2(10) ring motifs. Four C atoms of the 3-phenyl ring are disordered over two sets of sites [site occupancies = 0.745 (6) and 0.225 (6)].
doi:10.1107/S1600536812017849
PMCID: PMC3344653  PMID: 22590415
15.  (2E,4E)-Ethyl 5-(phenyl­sulfon­yl)penta-2,4-dienoate 
In the title compound, C13H14O4S, both C=C double bonds adopt an E conformation. In the crystal, mol­ecules are linked into centrosymmetric R 2 2(14) dimers via pairs of C—H⋯O hydrogen bonds.
doi:10.1107/S1600536812009907
PMCID: PMC3344046  PMID: 22589955
16.  Methyl (E)-2-({2-[(E)-(hy­droxy­imino)­meth­yl]phen­oxy}meth­yl)-3-phenyl­acrylate 
In the title compound, C18H17NO4, the hy­droxy­ethanimine group is essentially coplanar with the ring to which it is attached [C—C—N—O torsion angle = 179.94 (14)°]. The mol­ecules are linked into cyclic centrosymmetric R 2 2(6) dimers via O—H⋯N hydrogen bonds and the crystal packing is further stabilized by C—H⋯O inter­actions.
doi:10.1107/S1600536812002711
PMCID: PMC3295410  PMID: 22412521
17.  (E)-2-({2-[(E)-(Hy­droxy­imino)­meth­yl]phen­oxy}meth­yl)-3-p-tolyl­acrylonitrile 
In the title compound, C18H16N2O2, the hy­droxy­ethanimine group is essentially coplanar with the ring to which it is attached (C—C—N—O torsion angle = −176.9°). Mol­ecules are linked into cyclic centrosymmetric R 2 2(6) dimers via O—H⋯N hydrogen bonds.
doi:10.1107/S160053681200270X
PMCID: PMC3297297  PMID: 22412487
18.  Nonthermal Dielectric-Barrier Discharge Plasma-Induced Inactivation Involves Oxidative DNA Damage and Membrane Lipid Peroxidation in Escherichia coli▿  
Oxidative stress leads to membrane lipid peroxidation, which yields products causing variable degrees of detrimental oxidative modifications in cells. Reactive oxygen species (ROS) are the key regulators in this process and induce lipid peroxidation in Escherichia coli. Application of nonthermal (cold) plasma is increasingly used for inactivation of surface contaminants. Recently, we reported a successful application of nonthermal plasma, using a floating-electrode dielectric-barrier discharge (FE-DBD) technique for rapid inactivation of bacterial contaminants in normal atmospheric air (S. G. Joshi et al., Am. J. Infect. Control 38:293-301, 2010). In the present report, we demonstrate that FE-DBD plasma-mediated inactivation involves membrane lipid peroxidation in E. coli. Dose-dependent ROS, such as singlet oxygen and hydrogen peroxide-like species generated during plasma-induced oxidative stress, were responsible for membrane lipid peroxidation, and ROS scavengers, such as α-tocopherol (vitamin E), were able to significantly inhibit the extent of lipid peroxidation and oxidative DNA damage. These findings indicate that this is a major mechanism involved in FE-DBD plasma-mediated inactivation of bacteria.
doi:10.1128/AAC.01002-10
PMCID: PMC3067084  PMID: 21199923
19.  Diethyl [benzyl­amino­(1,3-diphenyl-1H-pyrazol-4-­yl)meth­yl]phospho­nate 
In the title compound, C27H30N3O3P, the pyrazole ring is essentially planar [maximum deviation = 0.002 (2) Å] and it forms dihedral angles of 9.3 (1) and 40.2 (1)°, respectively, with the phenyl rings attached to the N and C atoms. In the crystal, pairs of centrosymmetrically related mol­ecules are linked into dimers by N—H⋯O hydrogen bonds.
doi:10.1107/S1600536811032776
PMCID: PMC3200952  PMID: 22065814
20.  Dedicated pediatric cardiac intensive care unit in a developing country: Does it improve the outcome? 
Annals of Pediatric Cardiology  2011;4(2):122-126.
Introduction and Aim:
Focussed cardiac intensive care is known to produce better outcomes. We have evaluated the benefits of a dedicated Pediatric Cardiac Intensive Care Unit (PCICU) in the early postoperative outcomes of patients undergoing surgery for congenital heart disease.
Methods:
Prospectively collected data of 634 consecutive patients who underwent congenital heart surgery from September 2008 to September 2009 were analyzed. Midway through this period a dedicated PCICU was started. The patients who were treated in this new PCICU formed the study group (Group B, n = 318). The patients who were treated in a common postoperative cardiac surgery ICU formed the control group (Group A, n = 316). Early postoperative outcomes between the two groups were compared.
Results:
The two groups were comparable with respect to demographic data and intraoperative variables. The duration of mechanical ventilation in the dedicated pediatric cardiac ICU group (32.22 ± 52.02 hours) was lower when compared with the combined adult and pediatric surgery ICU group (42.92 ± 74.24 hours, P= 0.04). There was a shorter duration of ICU stay in the dedicated pediatric cardiac ICU group (2.69 ± 2.9 days vs. 3.43 ± 3.80 days, P = 0.001). The study group also showed a shorter duration of inotropic support and duration of invasive lines. The incidence of blood stream infections was also lower in the dedicated pediatric ICU group (5.03 vs. 9.18%, P = 0.04). A subgroup analysis of neonates and infants <1 year showed that the advantages of a dedicated pediatric intensive care unit were more pronounced in this group of patients.
Conclusions:
Establishment of a dedicated pediatric cardiac intensive care unit has shown better outcomes in terms of earlier extubation, de-intensification, and discharge from the ICU. Blood stream infections were also reduced.
doi:10.4103/0974-2069.84648
PMCID: PMC3180967  PMID: 21976869
Pediatric cardiac intensive care; dedicated intensive care unit; intensivist
21.  Irf8-driven myeloid differentiation is regulated by 12/15-lipoxygenase-mediated redox signaling 
Experimental hematology  2010;38(11):1036-1046.e4.
OBJECTIVES
Several transcription factors determine the cell fate decision between granulocytes and monocytes, but the upstream signal transduction pathways that govern myelopoiesis are largely unknown. Based on our observation of aberrant myeloid cell representation in hematopoietic tissues of 12/15-lipoxygenase (12/15-LOX)-deficient (Alox15) mice, we tested the hypothesis that polyunsaturated fatty acid metabolism regulates myelopoiesis.
METHODS
Multi-color flow cytometric analysis and methylcellulose assays were used to compare myelopoiesis and the differentiative capacity of progenitors from Alox15 and wild-type mice. Furthermore, we elucidated the mechanism by which 12/15-LOX is involved in regulation of myelopoiesis.
RESULTS
Granulopoiesis in Alox15 mice is increased while monopoiesis is reduced. Moreover, there is an accumulation of granulocyte-macrophage progenitors that exhibit defective differentiation. Mechanistically, we demonstrate that transcriptional activity of Irf8, which regulates myelopoiesis, is impaired in Alox15 progenitors and bone marrow-derived macrophages due to loss of 12/15-LOX-mediated redox regulation of Irf8 nuclear accumulation. Restoration of redox signaling in Alox15 bone marrow cells and GMP reversed the defect in myeloid differentiation.
CONCLUSIONS
These data establish 12/15-LOX-mediated redox signaling as a novel regulator of myelopoiesis and Irf8.
doi:10.1016/j.exphem.2010.07.004
PMCID: PMC2963586  PMID: 20647030
22.  WEAR BEHAVIOR OF CARBON NANOTUBE/HIGH DENSITY POLYETHYLENE COMPOSITES 
Carbon Nanotube/High Density Polyethylene (CNT/HDPE) composites were manufactured and tested to determine their wear behavior. The nanocomposites were made from untreated multi-walled carbon nanotubes and HDPE pellets. Thin films of the precursor materials were created with varying weight percentages of nanotubes (1%, 3%, and 5%), through a process of mixing and extruding. The precursor composites were then molded and machined to create test specimens for mechanical and wear tests. These included small punch testing to compare stiffness, maximum load and work-to-failure and block-on-ring testing to determine wear behavior. Each of the tests was conducted for the different weight percentages of composite as well as pure HDPE as the baseline. The measured mechanical properties and wear resistance of the composite materials increased with increasing nanotube content in the range studied.
doi:10.1016/j.mechmat.2009.04.003
PMCID: PMC2745171  PMID: 20161101
23.  LOCALIZATION OF THE SITES AND CHARACTERIZATION OF THE MECHANISMS BY WHICH ANTI-LIGHT CHAIN ANTIBODIES NEUTRALIZE THE ACTIONS OF THE BOTULINUM HOLOTOXIN 
Vaccine  2009;27(19):2616-2624.
The recombinant, catalytically active light chain of botulinum toxin type A was evaluated as a potential vaccine candidate. Previous studies have shown that the light chain can elicit protective immunity in vivo. [5], but the underlying basis for this observation was not determined. In the present study, antibodies directed against the light chain were shown to act at three different sites in the body to produce neutralization. Firstly, these antibodies acted to block toxin absorption into the body. This was demonstrated in vitro, in studies on binding and transport of toxin across epithelial monolayers, and in vivo, in studies on inhalation poisoning. Secondly, anti-light chain antibodies acted to promote clearance of toxin from the general circulation. This was demonstrated in vivo in studies on toxin levels in blood and in parallel studies on toxin accumulation in liver and spleen. Finally, anti-light chain antibodies acted to protect cholinergic nerves from botulinum toxin action. This was demonstrated in two types of in vitro assays: rate of paralysis of murine phrenic nerve-hemidiaphragm preparations and extent of binding to Neuro-2a cells. When taken together, these data show that anti-light chain antibodies can evoke three layers of protection against botulinum toxin.
doi:10.1016/j.vaccine.2009.02.051
PMCID: PMC2709450  PMID: 19428868
Botulinum toxin; Botulism vaccine; Neutralization
24.  Establishing a pediatric cardiac intensive care unit - Special considerations in a limited resources environment 
Pediatric cardiac intensive care has evolved as a distinct discipline in well-established pediatric cardiac programs in developed nations. With increasing demand for pediatric heart surgery in emerging economies, a number of new programs are being established. The development of robust pediatric cardiac intensive care units (PCICU) is critical to the success of these programs. Because of substantial resource limitations existing models of PCICU care cannot be applied in their existing forms and structure. A number of challenges need to be addressed to deliver pediatric cardiac intensive care in the developing world. Limitations in infrastructure, human, and material resources call for a number of innovations and adaptations. Additionally, a variety of strategies are required to minimize costs of care to the individual patient. This review provides a framework for the establishment of a new PCICU program in face of resource limitations typically encountered in the developing world and emerging economies.
doi:10.4103/0974-2069.64374
PMCID: PMC2921517  PMID: 20814475
Congenital heart surgery; critical care; developing country
25.  Molecular Biology of ADAMTS13 and Diagnostic Utility of ADAMTS13 Proteolytic Activity and Inhibitor Assays 
ADAMTS13, a reprolysin-like metalloprotease, limits platelet-rich thrombus formation in the small arteries by cleaving von Willebrand factor (vWF) at the Tyr1605-Met1606 peptide bond. Deficiency of plasma ADAMTS13 activity, due to either an inherited or an acquired etiology, may lead to a potentially lethal syndrome, thrombotic thrombocytopenic purpura (TTP). Molecular cloning and characterization of the ADAMTS13 gene have provided further insight into the structure-function relationships, biosynthesis, and regulation of the ADAMTS13 protease, in addition to understanding the pathogenesis of TTP and perhaps other thrombotic disorders. ADAMTS13 consists of a short propeptide, a typical reprolysin-like metalloprotease domain, followed by a disinte-grin-like domain, first thrombospondin type 1 (TSP1) repeat, Cys-rich domain, and spacer domain. The carboxyl terminus of ADAMTS13 has seven more TSP1 repeats and two CUB domains. ADAMTS13 is synthesized mainly in hepatic stellate cells, but also in vascular endothelial cells. Recognition and cleavage of vWF require the proximal carboxyl terminal domains, but not the middle and distal carboxyl terminal domains. Cleavage of vWF appears to be modulated by shear force, binding to platelet or platelet glycoprotein-1bα, heparin, inflammatory cytokine (interleukin-6), and chloride ion. At the site of thrombus formation, the ADAMTS13 may be inactivated by thrombin, plasmin, and factor Xa. Having a sensitive and specific assay for ADAMTS13 activity is not only critical to understand the basic biology of ADAMTS13 protease, but also to facilitate a more timely and accurate clinical diagnosis of TTP, and to initiate potentially life-saving plasma exchange therapy. Although many assays have been developed and tested for clinical applications, the fluorescent resonance energy transfer-vWF73 assay appears to be the simplest and most promising assay to date.
doi:10.1055/s-2005-925472
PMCID: PMC2577222  PMID: 16388417
Thrombotic thrombocytopenic purpura (TTP); von Willebrand factor; microvascular thrombosis; ADAMTS13; metalloprotease; assays; clinical application

Results 1-25 (28)