Antibiotic stewardship in a tertiary care hospital of a developing country: establishment of a system and its application in a unit-GASP Initiative.

PURPOSE: Despite the proven benefits of antimicrobial stewardship, models for executing the same in the developing countries are sparse. The present study highlights the approaches undertaken by our group in initiating one such program in a public sector tertiary level health care setting of a developing country. METHODS: The study focussed on development of a system after evaluation of existing issues and case study of implementation of the program in a unit within the hospital. The system building exercise included (1) development of generic data capture form for prospective audit and feedback; (2) development of an electronic system for data capture; (3) identification of key intervention points for strategy decision for stewardship in a particular unit; (4) application of the stewardship method and (5) evaluation of outcomes. RESULTS: A digital system for prospective audit was constructed after a background study. In the study unit, there was a significant decline in double anaerobic coverage. There was a significant decline in the average number of antimicrobials used per patients and a decrease in Defined Daily Dose of designated antimicrobials was noted. Additionally, there was an increase in the use of optimized doses. CONCLUSION: A system for undertaking antimicrobial stewardship with a mechanism for prospective audit was put in place. The system may be adopted by other public sector hospitals of the developing country.

New low bandgap near-IR conjugated D-A copolymers for BHJ polymer solar cell applications.

We synthesized two novel ultra low bandgap donor-acceptor (D-A) copolymers (E(g) ≤ 1.2 eV), containing the thiadiazoloquinoxaline unit as the main electron accepting unit (A) and benzodithiophene (BDT) and dithienosilole (DTS) as different donor units (D), denoted as P1 and P2, respectively, using the cross-coupling Stille reaction. The copolymers possess light absorption ranging from UV (350 nm) to near-IR (1300 nm) with optical bandgaps of 1.16 eV and 1.08 eV, respectively. Quantum-chemical calculations and experimental data were compared for proposing a more detailed concept for the optical and electronic properties of these copolymers which can be used as donors for polymer solar cells (PSCs). The PSCs based on optimized P1:PC71BM and P2:PC71BM showed overall power conversion efficiencies (PCEs) of 4.32% and 3.48%, respectively. Although P2 possesses a broad absorption coverage of up to 1300 nm, the lower PCE may be attributed to the low J(sc), due to the poor driving force for exciton dissociation, since the LUMO offset with PC71BM is less than 0.3 eV. The PCE has been significantly increased to 7.27% and 6.68% for solvent vapor annealing (SVA) treated P1:PC71BM and P2:PC71BM active layers, respectively. This improvement arises from the appropriate nanoscale morphology and an increase in hole mobility, induced by the SVA treatment of the active layers.

Synthesis and characterization of π-conjugated copolymers with thieno-imidazole units in the main chain: application for bulk heterojunction polymer solar cells.

In this paper the three new narrow bandgap D­A conjugated copolymers P1, P2 and P3 based on different weak donor fused thiophene-imidazole containing derivatives and the same benzothiadiazole acceptor unit were synthesized by Stille cross-coupling polymerization and characterized by 1H NMR, elemental analysis, GPC, TGA, DSC. These copolymers exhibit intensive absorbance in the range 350­900 nm and the optical bandgap lies in the range of 1.50­1.61 eV, which corresponds to the maximum photon flux of the solar spectrum. The electrochemical bandgap derived from cyclic voltammetry varies within the limits 1.47­1.65 eV and is approximately very close to the optical bandgap. The highest occupied molecular orbital (HOMO) energy level of all copolymers is deep lying (−5.24 eV and −5.37 eV and −5.25 eV for P1, P2 and P2, respectively) which shows that copolymers have good stability in the air and assured a higher open circuit voltage (Voc) for polymer BHJ solar cells. These copolymers were used as donors along with PC71BM and the BHJ polymer solar cells based on P1:PC71BM, P2:PC71BM and P3:PC71BM processed from chloroform (CF) solvent with 3 v% DIO as an additive showed an overall PCE of 4.55%, 6.76% and 5.16%, respectively.

Near infrared organic semiconducting materials for bulk heterojunction and dye-sensitized solar cells.

Dye sensitized solar cells (DSSCs) and bulk heterojunction (BHJ) solar cells have been the subject of intensive academic interest over the past two decades, and significant commercial effort has been directed towards this area with the vison of developing the next generation of low cost solar cells. Materials development has played a vital role in the dramatic improvement of both DSSC and BHJ solar cell performance in the recent years. Organic conjugated polymers and small molecules that absorb solar light in the visible and near infrared (NIR) regions represent a class of emering materials and show a great potential for the use of different optoelectronic devices such as DSSCs and BHJ solar cells. This account describes the emering class of near infrared (NIR) organic polymers and small molecules having donor and acceptors units, and explores their potential applications in the DSSCs and BHJ solar cells.

Application of solution processable squaraine dyes as electron donors for organic bulk-heterojunction solar cells.

New low bandgap small molecules based on a squaraine (SQ) chromophore, bis[4-(2,6-di-tert-butyl)vinylpyrylium]squaraine (TBU-SQ), bis[2,6-di-tert-butyl-4-(prop-1-en-2-yl)pyrylium]squaraine (MeTBU-SQ) and bis[4-(but-1-en-2-yl)-2,6-di-tert-butylpyrylium]squaraine (EtTBU-SQ), were synthesized and used as electron donors along with PC70BM for their application in solution processed organic bulk-heterojunction (OBHJ) solar cell (SC). The long wavelength of these SQ dyes are located in between 650-750 nm in thin films and the optical bandgaps are about 1.64, 1.52 and 1.48 eV, respectively. The electrochemical properties of these SQ dyes indicate that they are well suited for the fabrication of OBHJSCs as electron donors along with fullerene derivatives as electron acceptors. The OBHJ photovoltaic (PV) devices fabricated with the blend of TBU-SQ:PC70BM, MeTBU-SQ:PC70BM and EtTBU-SQ:PC70BM cast from chloroform (CF) solvent exhibited a power conversion efficiency (PCE) of 1.71%, 2.15%, and 1.89%, respectively. The PCE of the OBHJSCs based on MeTBU-SQ:PC70BM blends cast from DIO-THF (DIO = 1,8-diiodooctane) additive solvent and cast from DIO-THF with subsequent thermal annealing have been further improved up to 2.73% and 3.14%, respectively. This enhancement in the PCE is attributed to the improvement in the crystalline nature of the blend and more balanced charge transport resulting from the higher hole mobility. All these results have been supported by the quantum chemical calculations.

Isolation and characterization of heavy metal resistant bacteria from Barak River contaminated with pulp paper mill effluent, South Assam.

A group of 15 heavy metal resistant bacteria were isolated from Barak River contaminated with paper and pulp effluents. These isolates displayed different degrees of chromium tolerance. Four isolates showed 34 %-49 % of growth at a concentration of 4.0 mM of Cr(6+) and subjected to chromium reduction assay under aerobic condition. The isolate E (4) showed highest reduction (34.38 %) followed by E (3) and K(6)PA6, both showed 28.75 % reduction and then D (2) (27.5 %) after 72 h of incubation. These 4 isolates also showed different degrees of resistance to other heavy metals like Ni, Cu, Co and Cd. Antibiotic sensitivity profile of these selected bacterial strains was determined against 10 different antibiotics. Isolate E (4) appeared to be most susceptible being inhibited by eight antibiotics and resistant to penicillin G and ampicillin. The isolate E (3) was resistant to as many as five antibiotics and showed susceptible responses to the rest of the antibiotics. Both the isolates K(6)PA6 and D (2) were resistant to four antibiotics and showed intermediate to susceptible responses to the rest of the antibiotics.

Transformation of pWWO in Rhizobium leguminosarum DPT to Engineer Toluene Degrading Ability for Rhizoremediation.

Rhizoremediation of organic xenobiotics is based on interactions between plants and their associated micro-organisms. The present work was designed to engineer a bacterial system having toluene degradation ability along with plant growth promoting characteristics for effective rhizoremediation. pWWO harboring the genes responsible for toluene breakdown was isolated from Pseudomonas putida MTCC 979 and successfully transformed in Rhizobium DPT. This resulted in a bacterial strain (DPT(T)) which had the ability to degrade toluene as well as enhance growth of host plant. The frequency of transformation was recorded 5.7 × 10(-6). DPT produced IAA, siderophore, chitinase, HCN, ACC deaminase, solubilized inorganic phosphate, fixed atmospheric nitrogen and inhibited the growth of Fusarium oxysporum and Macrophomina phaseolina in vitro. During pot assay, 50 ppm toluene in soil was found to inhibit the germination of Cajanus cajan seeds. However when the seeds bacterized with toluene degrading P. putida or R. leguminosarum DPT were sown in pots, again no germination was observed. Non-bacterized as well as bacterized seeds germinated successfully in toluene free soil as control. The results forced for an alternative mode of application of bacteria for rhizoremediation purpose. Hence bacterial suspension was mixed with soil having 50 ppm of toluene. Germination index in DPT treated soil was 100% while in P. putida it was 50%. Untreated soil with toluene restricted the seeds to germinate.

Value addition to bamboo shoots: a review.

Bamboo shoot forms a traditional delicacy in many countries. Being low in fat content and high in potassium, carbohydrate, dietary fibres, Vitamins and active materials, bamboo shoots are consumed in raw, canned, boiled, marinated, fermented, frozen, liquid and medicinal forms. Although the fresh bamboo shoots of species like Dendraocalamus giganteus are healthier and nutritionally rich, the young shoots, after fortification, can be consumed by processing into a wide range of food products with longer shelf-life and better organoleptic qualities. However, the consumption pattern of bamboo shoots in most of the countries is traditional, non-standardized, seasonal and region-specific with little value addition. Therefore, there exists a great opportunity, especially for the organized food processing sectors to take up the processing of bamboo shoot-based food products in an organized manner. The present article gives an insight into the global scenario of bamboo shoot-based food products and their consumption pattern, the quality attributes, and the opportunities for value addition along with future prospects in view of international food safety, security and nutrition.

Association of PARK-2 Non-synonyms Polymorphisms and Their In Silico Validation Among North Indian Colorectal Cancer Patients.

PURPOSE: PARK2 is a potential tumour suppressor gene and its genetic alterations (regionic loss) are common across many human cancers. The association of PARK2 germline variations (SNPs) with Parkinson's has been shown, but their association in development and progression of cancer remains elusive. The aim of this study was to identify association of PARK2 polymorphisms (rs1801474, rs1801334) with colorectal cancer in a case control study design. METHODS: This case control study included a total of 650 genetically unrelated subjects comprising 300 colorectal cancer cases and 350 healthy controls belonging to North Indian. Both SNPs were analyzed using the PCR-RFLP assay. Statistical analysis for describing risk and association was performed using SPSS-17 software. Structural deviations due to non- synonymous substitutions (S167N and D394N) were analyzed using MD simulations. RESULTS: The genotype distributions of both the SNPs were in Hardy-Weinberg equilibrium. For both the polymorphisms, the allelic model showed statistically significant risk with OR ~ 1.3. Many of the associations remained significant even after Bonferroni correction (P < 0.00125). The result suggested that both S167N and D394N were deviated from wild type and structures and were stable after 5 ns. The average value of RMSD for backbone atoms was calculated from 5 to 10 ns molecular dynamics simulation data. CONCLUSION: In conclusion, our study revealed a significant association of PARK2 SNPs with colorectal cancer as well as their relations with other clinical parameters highlighting their contribution towards colorectal cancer susceptibility in North Indian population.

Bulk heterojunction photovoltaics using broadly absorbing small molecules based on 2-styryl-5-phenylazo-pyrrole.

Three new soluble small molecules (B, B6, and A) with a low band gap based on 2-styryl-5-phenylazo-pyrrole were synthesized. Molecules B and B6 contained pyrrole and N-hexylpyrrole, respectively, as the central unit, which was connected to N,N-dimethylphenyl-4-azo on one side of the pyrrole molecule. Molecule A contained N-hexylpyrrole as the central unit, which was connected to anthracenyl-9-azo on one side of the pyrrole molecule. The other side of the pyrrole molecule was connected to cyanovinylene 4-nitrophenyl for all molecules. The long-wavelength absorption maximum of the molecules was located at 601-637 nm, and their optical band gap was 1.62-1.67 eV. The photovoltaic properties have been investigated using blends of B, B6, or A with PCBM, and it was found that the device based on A:PCBM had a higher power conversion efficiency (PCE) (2.06%) than the devices based on B:PCBM (1.33%) and B6:PCBM (1.36%). This has been attributed to the higher hole mobility, the lower band gap of A relative to that of B or B6, and the higher energy difference between the LUMO of A and PCBM. The effect of solvent annealing and thermal-solvent annealing on the photovoltaic response of the device based on the A:PCBM blend has been investigated, and it was found that the devices based on solvent-treated and subsequent thermally annealed blends have PCEs of 2.56 and 2.83%, respectively. The increase in the PCE has been attributed to the enhanced crystallinity of the blend and the improvement in the charge transport due to a reduction in the difference between the electron and hole mobility in the blend.

Synthesis of a low-band-gap small molecule based on acenaphthoquinoxaline for efficient bulk heterojunction solar cells.

A novel small molecule (SM) with a low-band-gap based on acenaphthoquinoxaline was synthesized and characterized. It was soluble in polar solvents such as N,N-dimethylformamide and dimethylacetamide. SM showed broad absorption curves in both solution and thin films with a long-wavelength maximum at 642 nm. The thin film absorption onset was located at 783 nm, which corresponds to an optical band gap of 1.59 eV. SM was blended with PCBM to study the donor-acceptor interactions in the blended film morphology and the photovoltaic response of the bulk heterojunction (BHJ) devices. The cyclic voltammetry measurements of the materials revealed that the HOMO and LUMO levels of SM are well aligned with those of PCBM, allowing efficient photoinduced charge transfer and suitable open circuit voltage, leading to overall power conversion efficiencies (PCEs) of approximately 2.21 and 3.23% for devices with the as-cast and thermally annealed blended layer, respectively. The increase in the PCE with the thermally annealed blend is mainly attributed to the improvement in incident photon to current efficiency (IPCE) and short circuit photocurrent (J(sc)). Thermal annealing leads to an increase in both the crystallinity of the blend and hole mobility, which improves the PCE.

Investigation of haemorrhagic enteritis in pygmy hogs (Sus salvanius) from India.

The pygmy hog is a representative of the smallest and rarest wild species of known living Suidae. This paper reports the investigation of haemorrhagic enteritis encountered amongst the pygmy hogs at the Research and Breeding Centre of the Pygmy Hog Conservation Programme, Guwahati, Assam, India. Three out of 68 pygmy hogs died of enteric infection. Post-mortem examination and bacteriological investigation of two out of the three animals that died revealed clostridial infection. The isolates harboured two plasmids of molecular weight 42.8 kilobases (kb) and 51.9 kb. Clostridium perfringens Type A positive for the beta2 toxin (cpb2) gene was detected by polymerase chain reaction. Sequence analysis of the partial alpha toxin (cpa) gene showed 98% to 100% homology with isolates from different geographical locations.

Coenzyme Q10 ameliorates cadmium induced reproductive toxicity in male rats.

This study aimed at investigating the protective role of CoQ10 against cadmium (Cd)-induced reproductive toxicity in male rats. Adult male Wistar rats were exposed to an acute dose of Cd (25 mg/kg bwt; Cd group), Cd+CoQ10 (25 mg/kg bwt Cd+10 mg CoQ10; Cd-Q10 group) and distilled water (control) in vivo for 15 consecutive days and semen quality was assessed. A significant reduction was noted in sperm concentration, progressive motility, morphology and DNA integrity in both Cd- and Cd-Q10 groups in comparison to control indicating Cd-induced testicular lipid per oxidation (LPO) and decline in indigenous antioxidant defense system as measured by total antioxidant capacity (TAC) (p<0.05). However, simultaneous co-administration of CoQ10 along with Cd (Cd-Q10 group) was able to improve sperm concentration, motility, progressive motility, morphology, DNA integrity, and testicular TAC as well as lower LPO compared to Cd group (p<0.05). Results indicate that used dose of CoQ10 is capable of moderately ameliorating reproductive toxicity of Cd by improving semen quality and reducing testicular oxidative stress.

Association of PARK2 promoter polymorphisms and methylation with colorectal cancer in North Indian population.

Different diseases have been associated with PARK2/PACRG overlapping promoter polymorphisms (rs2276201 and rs9347683) in the recent past. However association of these polymorphisms with cancer remains elusive till date. Thus in this study we evaluated association between these polymorphisms and colorectal cancer (CRC) incidences among North Indians. Genomic DNA was isolated using venous blood of 400 unrelated subjects (200 CRC cases and 200 healthy controls) of North Indian origin. Both SNPs were genotyped using PCR-RFLP method. Promoter methylation status in tumor DNA was checked using MS-PCR. Statistical analysis was performed using SPSS-17 software. In-silico predictions for transcription factor binding were performed using "PROMO" a freely available online tool. SNP rs2276201 showed statistically significant difference (P = 0.047) among cases and controls while rs9347683 did not (P = 0.113). The TC genotype (OR: 1.855, 95% CI: 1.021-3.369, P = 0.043), CC genotype (OR: 1.617, 95% CI: 1.042-2.510, P = 0.032), TT vs CT+CC genetic model (OR: 1.60, P = 0.0158) and allelic model (OR: 1.3931, 95% CI: 1.0498-1.8485, P = 0.0214) of rs2276201 showed significant risk for CRC. For rs9347683 AC genotype (OR: 1.604, 95% CI: 1.019-2.523, P = 0.041) and AA vs AC+CC genetic model (OR: 1.57, P = 0.039) showed significant risk. Haplotype CC provided significant risk (OR: 1.618, 95% CI: 1.112-2.352, P = 0.011) whereas haplotype TA provided significant protection (OR: 0.732, 95% CI: 0.543-0.987, P = 0.040) against CRC. Promoter methylation was significantly higher in tumor grade III + IV (OR: 2.37, P = 0.019), while PARK2 expression was lower in cancer tissues compared to normal tissue. Here we provide the first report where PARK2 promoter SNP's rs2276201 and rs9347683 are shown to be significantly associated with the risk of CRC development.

A triazine di(carboxy)porphyrin dyad versus a triazine di(carboxy)porphyrin triad for sensitizers in DSSCs.

Two porphyrin-chromophores, i.e. triad PorZn-(PorCOOH)(2)-(piper)2 (GZ-T1) and dyad (PorZn)(2)-NMe2 (GZ-T1), have been synthesized and their photophysical and electrochemical properties have been investigated. The optical properties together with the appropriate electronic energy levels, i.e. the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels, revealed that both porphyrin assemblies can function as sensitizers for dye sensitized solar cells (DSSCs). The and -based DSSCs have been prepared and studied using 20 mM CDCA as coadsorbent and were found to exhibit an overall power conversion efficiency (PCE) of 5.88% and 4.56%, respectively (under an illumination intensity of 100 mW cm(-2) with TiO(2) films of 12 µm). The higher PCE of the -sensitized DSSC, as revealed from the current-voltage characteristic under illumination and the incident photon to current conversion efficiency (IPCE) spectra of the two DSSCs, is mainly attributed to its enhanced short circuit current (J(sc)), although both the open circuit voltage (V(oc)) and the fill factor are improved too. The electrochemical impedance spectra (EIS) demonstrated a shorter electron transport time, longer electron lifetime and higher charge recombination resistance for the DSSC sensitized with the dye as well as a larger dye loading onto the TiO(2) surface.

Genotoxic effects of malathion: an organophosphorus insecticide, using three mammalian bioassays in vivo.

The genotoxic effects of malathion was evaluated using chromosome aberration, sister chromatid exchange (SCE) and sperm abnormality assays in mice. All the three acute doses (2.5, 5 and 10mg/kg) of malathion tested in the present study, induced significant dose-dependent increase in the frequency of chromosome aberrations and sperm abnormalities, but did not affect the total sperm count. The highest acute dose induced a >12-fold increase in the frequency of chromosome aberrations, two-fold increase in the frequency of SCEs and four-fold increase in the frequency of sperms with abnormal head morphology following intraperitoneal (i.p.) exposure. Further, a significant increase in the frequency of SCEs was observed, but the increase was not dose-dependent. At higher doses, malathion induced a moderate delay in cell cycle as evident from the increase in average generation time (AGT). The present findings suggest that technical grade malathion is a potent genotoxic agent and may be regarded as a potential germ cell mutagen also.

Fenvalerate-induced chromosome aberrations and sister chromatid exchanges in the bone marrow cells of mice in vivo.

Fenvalerate, a synthetic pyrethroid insecticide, is commonly used in agriculture and other domestic applications due to its high insecticidal activity and low mammalian-, avian- and phyto-toxicities. However, the genotoxic effect of fenvalerate is highly equivocal. In the present study the genotoxic effects of fenvalerate was evaluated using structural chromosome aberration (CA) and sister chromatid exchange (SCE) assays in mice. Out of the three doses (5, 10 and 20 mg/kg) tested, statistically significant increase in CA was found following intra peritoneal (i.p.) treatment of 2 0 mg/kg of fenvalerate for 24 h (P<0.01) and 48 h (P<0.05) only. Neither the acute doses of 5 and 10 mg/kg, nor the sub-acute dose (5x4 mg/kg) of fenvalerate could induce any significant effect. All the three acute doses induced significant increase in the frequency of SCEs (P<0.01) in the bone marrow cells, which showed a significant dose-response correlation (r=0.9541, P<0.05). With certain reservations to possible impurities, from the present findings technical grade fenvalerate may be considered as a weak clastogen and a potent inducer of SCEs in mice.

Effect of fire on soil microorganisms in a Meghalaya pine forest.

The effect of man-made fire on soil microbial population in a natural subtropical pine forest eco-system, was studies. a nearly fifty years old pine (Pinus kesiya Royle) forest was cut and burnt in March 1977. Another half of this pine forest was left uncut and unburnt. Microbial population was destroyed completely just after the burning and recolonization occurred after some days. Bacteria and actinomycetes were found to be the first colonizers followed by fungi. Burning initiated better growth and higher population of bacteria after two or three showers. Bacterial population was highest in July in burnt and in May in unburnt forest. Maximum fungal population in burnt site was recorded in July while it was highest in april and May in unburnt site. Penicillium spp., Cladosporium sp. and Trichoderma sp. were found to be first colonizing fungi just after the burning. In unburnt forest eco-system Absidia sp., Trichoderma sp., Fusarium sp. and Penicillium spp. were found to be dominant.

Studies on heme and heme oxygenase during Plasmodium berghei infection in golden hamsters.

Heme and heme degrading enzymes namely heme-oxygenase (HO) and biliverdin reductase (BR) were monitored in liver and spleen during Plasmodium berghei infection in golden hamsters. There was a sequential rise in the levels of heme and HO with the rise in parasitaemia. BR was also significantly increased in these organs following infection.