Site-specific orthometallation via C–H bond activation and syntheses of ruthenium(iii) organometallics: studies on nitric oxide (NO) reactivity and photorelease of coordinated NO

σ-Aryl ruthenium(iii) complexes were synthesized by C–H bond activation and organometallic nitrosyl complexes were synthesized and characterized by spectroscopy and crystal structure. Coordinated NO molecule was found to be photolabile.

Detection of mutations in mtrR gene in quinolone resistant strains of N. gonorrhoeae isolated from India

BACKGROUND AND OBJECTIVES

Emergence of multi-drug resistant Neisseria gonorrhoeae resulting from new genetic mutation is a serious threat in controlling gonorrhea. This study was undertaken to identify and characterise mutations in the mtrR genes in N.gonorrhoeae isolates resistant to six different antibiotics in the quinolone group.

MATERIALS AND METHODS

The Minimum inhibitory concentrations (MIC) of five quinolones for 64 N.gonorrhoeae isolates isolated during Jan 2007-Jun 2009 were determined by E-test method. Mutations in MtrR loci were examined by deoxyribonucleic acid (DNA) sequencing.

RESULTS

The proportion of N.gonorrhoeae strains resistant to anti-microbials was 98.4% for norfloxacin and ofloxacin, 96.8% for enoxacin and ciprofloxacin, 95.3% for lomefloxacin. Thirty-one (48.4%) strains showed mutation (single/multiple) in mtrR gene. Ten different mutations were observed and Gly-45 → Asp, Tyr-105 → His being the most common observed mutation.

CONCLUSION

This is the first report from India on quinolone resistance mutations in MtrRCDE efflux system in N.gonorrhoeae. In conclusion, the high level of resistance to quinolone and single or multiple mutations in mtrR gene could limit the drug choices for gonorrhoea.

An analysis of underlying factors for seasonal variation in gonorrhoea in India: a 6-year statistical assessment

PURPOSE

A statistical assessment of a disease is often necessary before resources can be allocated to any control programme. No literature on seasonal trends of gonorrhoea is available from India.

OBJECTIVES

The objectives were (1) to determine, if any, seasonal trends were present in India (2) to describe factors contributing to seasonality of gonorrhoea (3) to formulate approaches for gonorrhoea control at the national level.

MATERIALS AND METHODS

Seasonal indices for gonorrhoea were calculated quarterly in terms of a seasonal index between 2005 and 2010. Ratio-to-moving average method was used to determine the seasonal variation. The original data values in the time-series were expressed as percentages of moving averages. Results were also analyzed by second statistical method i.e. seasonal subseries plot.

RESULTS

The seasonally adjusted average for culture-positive gonorrhoea cases was highest in the second quarter (128.61%) followed by third quarter (108.48%) while a trough was observed in the first (96.05%) and last quarter (64.85%). The second quarter peak was representative of summer vacations in schools and colleges. Moreover, April is the harvesting month followed by celebrations and social gatherings. Both these factors are associated with increased sexual activity and partner change. A trough in first and last quarter was indicative of festival season and winter leading to less patients reporting to the hospital.

CONCLUSION

The findings highlight the immediate need to strengthen sexual health education among young people in schools and colleges and education on risk-reduction practices especially at crucial points in the calendar year for effective gonorrhoea control.

Validation of ethnomedicinal potential of Tinospora cordifolia for anticancer and immunomodulatory activities and quantification of bioactive molecules by HPTLC

ETHNOPHARMACOLOGICAL RELEVANCE

Tinospora cordifolia (Willd.) Miers ex Hook. f. & Thomas. (Menispermaceae) is one of the most widely used plants in various traditional medicinal systems including "Ayurveda". The plant is used for the treatment of jaundice, rheumatism, urinary disorder, skin diseases, diabetes and anemia. The phytoconstituents present in the plant belongs to different class of compounds such as alkaloids, diterpenoids lactones, glycosides, steroids, phenol, aliphatic compounds and polysaccharides.

AIM OF THE STUDY

The aim of present study was the isolation, structure elucidation, quantification and pharmacological evaluation of secondary metabolites from T. cordifolia for anticancer and immunomodulatory activities.

MATERIALS AND METHODS

Different extracts and fractions were prepared from the stem of T. cordifolia. Pure molecules were isolated using normal phase chromatography and characterized on the basis of NMR and mass spectroscopic techniques. The anti-cancer and immunomodulatory activities of different extracts, fractions and isolated compounds were evaluated against four different human cancer cell lines, KB (human oral squamous carcinoma), CHOK-1 (hamster ovary), HT-29 (human colon cancer) and SiHa (human cervical cancer) and murine primary cells respectively. A simple, normal phase HPTLC method was also developed for the quantification of three bioactive compounds i.e N-formylannonain (1), 11-hydroxymustakone (5) and yangambin (8) in the stem of T. cordifolia hosted on fifteen different plants.

RESULTS

Chromatographic purification of different fractions led to the isolation of eight pure molecules i.e N-formylannonain (1), magnoflorine (2), jatrorrhizine (3) palmatine (4), 11-hydroxymustakone (5), cordifolioside A (6), tinocordiside (7) and yangambin (8). All extracts and fractions were active against KB and CHOK-1 cells whereas among the pure molecules palmatine (4) was found to be active against KB and HT-29; tinocordiside (7) against KB and CHOK-1; yangambin (8) against KB cells however N-formylannonain (1) and 11-hydroxymustakone (5), was found active for immunomodulatory activity. HPTLC quantification of three active molecules i.e N-formylannonain (1), 11-hydroxymustakone (5), and yangambin (8) were found in highest quantity in the stem of T. cordifolia hosted on Mangifera indica, however, other two active molecules were not quantified due to their insufficient quantity.

CONCLUSION

Eight compounds have been isolated and characterized belonging to different classes. The pharmacological evaluation of extract, fractions and pure molecules revealed the ethnomedicinal value of T. cordifolia for anticancer and immunomodulatory activities.

Percutaneous cholecystostomy is safe and effective option for acute calculous cholecystitis in select group of high-risk patients

PURPOSE

In high-risk patients with acute calculous cholecystitis (ACC), percutaneous cholecystostomy (PC) can serve as a bridging option to cholecystectomy [laparoscopic cholecystectomy (LC)] or as definitive treatment. The purpose of this study was to identify predictors of the need for permanent PC.

METHODS

Data from 257 PCs performed for ACC (mean age 67.3 ± 14) was collected for a 10-year period. Demographic and clinical characteristics at initial admission, co-morbidities were analyzed. Patients who underwent interval LC were defined as the surgery group (SG; n = 163, 63.4 %) and the remaining patients as the non-SG (NSG; n = 94, 36.6 %).

RESULTS

Patients in the SG were significantly younger and had a shorter length of hospital stay (p < 0.01). The rate of coronary artery disease (CAD; 63.2 vs. 20.2 %), chronic renal failure (14.9 vs. 6.1 %), and the mean number of co-morbidities (2.2 vs. 1.4) were significantly higher in the NSG. Sepsis at admission was more common in the NSG (19.1 vs. 4.9 %, p < 0.001). 56 patients (34.4 %) in the SG and 24 patients (25.5 %) in the NSG developed tube-related complications. In hospital mortality was similar between the groups. Multivariate analysis showed that age ≥75, increased alkaline phosphatase (ALK-P), history of CAD, were predictors of PC as a definite treatment in this high-risk group of patients with ACC.

CONCLUSIONS

High operative risk due to older age and CAD preclude LC in more than one-third of patients following PC especially presenting with sepsis and elevated ALK-P. This study suggests that PC could be a safe treatment option in this select group of high-risk patients.

A prospective study to evaluate and compare laryngeal mask airway ProSeal and i-gel airway in the prone position

Background:

Prone position is commonly used to provide surgical access to a variety of surgeries. In view of the advantages of induction of anesthesia in the prone position, we conducted a randomized study to evaluate and compare ProSeal laryngeal mask airway (LMA) and i-gel in the prone position.

Materials and Methods:

Totally, 40 patients of either sex as per American Society of Anesthesiologists physical status I or II, between 16 and 60 years of age, scheduled to undergo surgery in prone position were included in the study. After the patients positioned themselves prone on the operating table, anesthesia was induced by the standard technique. LMA ProSeal was used as an airway conduit in group 1 while i-gel was used in group 2. At the end of surgery, the airway device was removed in the same position.

Results:

Insertion of airway device was successful in first attempt in 16, and 17 cases in ProSeal laryngeal mask airway (PLMA) and i-gel groups, respectively. A second attempt was required to secure the airway in 4 and 3 patients in PLMA and i-gel groups, respectively. The mean insertion time was 21.8 ± 2.70 s for group 1 and 13.1 ± 2.24 s for group 2, the difference being statistically significant (P < 0.05). The mean seal pressure in group 1 was 36 ± 6.22 cm H₂ O and in group 2 was 25.4 ± 3.21 cm H₂ O. The difference was statistically significant (P < 0.05). 13 patients in group 1 had fiberoptic bronchoscopy (FOB) grade 1 while it was 6 for group 2. The remaining patients in both groups had FOB grade 2.

Conclusion:

Insertion of supraglottic airways and conduct of anesthesia with them is feasible in the prone position. The PLMA has a better seal while insertion is easier with i-gel.

Association of DC-SIGNR Expression in Peripheral Blood Mononuclear Cells with DC-SIGNR Genotypes in HIV-1 Infection

Dendritic cell-specific intracellular adhesion molecule 3 grabbing nonintegrin related molecule (DC-SIGNR) is a C-type lectin, calcium-dependent carbohydrate-binding protein, which can act as a cell-adhesion and pathogen recognition receptor. DC-SIGNR is known to be highly expressed on liver sinusoidal cells and in the lymph nodes. However, its expression in peripheral blood mononuclear cells (PBMCs) in HIV-1 infection has not been addressed. Therefore, this study determined the expression of DC-SIGNR in PBMCs of HIV-1-infected patients and healthy seronegative individuals by real-time polymerase chain reaction and assessed its correlation with CD4+ T cell counts and DC-SIGNR genotypes. A significantly higher expression of DC-SIGNR was observed in the PBMCs of HIV-1-infected patients compared with healthy seronegative individuals. Further, there was a negative correlation between DC-SIGNR expression and CD4+ T cell counts and positive with viral load, with higher DC-SIGNR expression in the PBMCs of HIV-1-infected patients with a CD4+ T cell count <200 cells/μL than those with >200 cells/μL. This is the first study to report the expression of DC-SIGNR in PBMCs of HIV-1-infected patients. A salient finding of this study is that the DC-SIGNR expression was higher in HIV-1-infected patients, and its positive correlation with viral load and negative with CD4+ T cells counts suggesting a potential role of DC-SIGNR in HIV-1 infection.

Abstract 600: Novel Assays to Determine in vivo Platelet Activation

In vivo platelet activation is associated with several pathologic entities, including acute coronary syndrome, essential thrombocythemia, anti-phospholipid antibody syndrome, diabetes and metabolic syndrome. The need for more robust biomarkers with which to assess platelet activation in vivo in human diseases is well recognized. Our lab has developed two novel assays to study in vivo platelet activation and rate of turnover.

During platelet activation, malondialdehyde (MDA) is produced by the thromboxane synthase in amounts equimolar to thromboxane A2 and also non-enzymatically by lipid peroxidation resulting from the oxidative processes that accompany activation. MDA is a reactive dicarbonyl that reacts with amines, notably lysines on proteins, yielding covalent modifications of the proteins that then accumulate over the lifetime of the platelet. We developed an LC/MS/MS method for quantification of the most stable of three MDA adducts, the dilysyl-MDA crosslink, employing a [13C12] labeled internal standard. We found that activation of platelets with arachidonic acid leads to an increase in the levels of dilysyl-MDA crosslinks in platelets, which is inhibited by the thromboxane synthase inhibitor, ozagrel, by the cyclooxygenase inhibitor, aspirin, and by scavengers of reactive carbonyls, 3- methoxysalicylamine and Salicylamine.

High platelet turnover has been associated with increased risk for thrombosis and failure of antiplatelet agents. We propose a novel approach to studying platelet turnover by labeling platelets in vivo by oral administration of aspirin containing a deuterium labeled acetyl group (d3-aspirin). We can measure the clearance of d3-labeled platelets by using LC/MS/MS to measure the tryptic peptide (SLK) of COX-1 labeled with d3. This approach avoids exposure to radioactivity and the artifact resulting from manipulation of platelets labeled ex vivo.

The results of this study provide two novel assays with the potential to serve as markers of in vivo platelet activation and turnover, which may be useful in predicting thrombotic risk and efficacy of antiplatelet therapy in patients with medical conditions associated with platelet hyperactivity and high rate of platelet turnover.

Chemical Prospection of Important Ayurvedic Plant Tinospora cordifolia by UPLC-DAD-ESI-QTOF-MS/MS and NMR

A rapid, sensitive, and accurate ultra-performance liquid chromatography coupled with mass spectrometric method (UPLC-MS) was developed and validated for simultaneous determination of four bioactive compounds, syringin (3), cordifolioside A (4), magnoflorine (6) and tinocordiside (10) in the stem of Tinospora cordifolia. The analysis was performed using an Acquity C18 column and gradient elution of 0.05% formic acid in water and acetonitrile at a detection wavelength of 267 nm in 5 min. A high correlation coefficient (r2 > 0.998) indicated good correlation between investigated compounds concentration and their peak area within the test ranges. The LODs for compounds 3, 4, 6 and 10 were 1.95, 0.97, 3.90 and 0.97 ng/mL, respectively, and LOQs were 6.64, 3.20, 12.87 and 3.20 ng/mL, respectively. The overall intra- and inter-day variations of the four compounds were less than 1%. The variation of these four bioactive compounds in T. cordifolia hosted on fifteen different trees was also determined. The compounds (3, 4, 6 and 10) were found in high amount in the T. cordifolia hosted on Azadirachta indica and Mangifera indica as compared with other plants. Twelve compounds were identified on the basis of their mass and UV-vis spectra. The NMR fingerprinting of the extract revealed the presence of alkaloids, fatty acid methyl esters, polysaccharides and marker components of T. cordifolia.

Phase evolution and electrical properties of Co–Sb alloys fabricated from Co/Sb bilayers by thermal annealing and ion beam mixing

Thermoelectric power enhancement of ion beam synthesized Co–Sb alloy thin films.

Chemical prospection of important ayurvedic plant Tinospora cordifolia by UPLC-DAD-ESI-QTOF-MS/MS and NMR

A rapid, sensitive, and accurate ultra-performance liquid chromatography coupled with mass spectrometric method (UPLC-MS) was developed and validated for simultaneous determination of four bioactive compounds, syringin (3), cordifolioside A (4), magnoflorine (6) and tinocordiside (10) in the stem of Tinospora cordifolia. The analysis was performed using an Acquity C18 column and gradient elution of 0.05% formic acid in water and acetonitrile at a detection wavelength of 267 nm in 5 min. A high correlation coefficient (r2 > 0.998) indicated good correlation between investigated compounds concentration and their peak area within the test ranges. The LODs for compounds 3, 4, 6 and 10 were 1.95, 0.97, 3.90 and 0.97 ng/mL, respectively, and LOQs were 6.64, 3.20, 12.87 and 3.20 ng/mL, respectively. The overall intra- and inter-day variations of the four compounds were less than 1%. The variation of these four bioactive compounds in T. cordifolia hosted on fifteen different trees was also determined. The compounds (3, 4, 6 and 10) were found in high amount in the T. cordifolia hosted on Azadirachta indica and Mangifera indica as compared with other plants. Twelve compounds were identified on the basis of their mass and UV-vis spectra. The NMR fingerprinting of the extract revealed the presence of alkaloids, fatty acid methyl esters, polysaccharides and marker components of T. cordifolia.

Enhancement of thermoelectric power of PbTe:Ag nanocomposite thin films

Formation of nanostructures results in the enhancement in thermoelectric power of PbTe:Ag thin films.

Synthesis and characterization of Au–Fe alloy nanoparticles embedded in a silica matrix by atom beam sputtering

AuFe alloy nanoparticles (NPs) embedded in a silica matrix were synthesized using an atom beam sputtering setup. Increasing the metal fraction in the thin films from 16 at% to 33 at% results in the formation of alloy NPs.