Quinaldine Red as a fluorescent probe for determining the melting temperature (Tm) of proteins: a simple, rapid and high-throughput assay.

Proteins play an important role in biological systems and several proteins are used in diagnosis, therapy, food industry etc. Thus, knowledge about the physical properties of the proteins is of utmost importance, which will aid in understanding their function and subsequent applications. The melting temperature (Tm) of a protein is one of the essential parameters which gives information about the stability of a protein under different conditions. In the present study, we have demonstrated a method for determining the Tm of proteins using the supramolecular interaction between Quinaldine Red (QR) and proteins. Using this method, we have determined the Tm of 5 proteins and compared our results with established protocols. Our results showed good agreement with the other methods and published values. The method developed in this study is inexpensive, quick, and devoid of complex instruments and pre/post-treatment of the samples. In addition, this method can be adopted for high throughput in multi-plate mode. Thus, this study projects a new methodology for Tm determination of various proteins with user friendly operation.

Identifying appropriate prediction models for estimating hourly temperature over diverse agro-ecological regions of India.

The present study tests the accuracy of four models in estimating the hourly air temperatures in different agroecological regions of the country during two major crop seasons, kharif and rabi, by taking daily maximum and minimum temperatures as input. These methods that are being used in different crop growth simulation models were selected from the literature. To adjust the biases of estimated hourly temperature, three bias correction methods (Linear regression, Linear scaling and Quantile mapping) were used. When compared with the observed data, the estimated hourly temperature, after bias correction, is reasonably close to the observed during both kharif and rabi seasons. The bias-corrected Soygro model exhibited its good performance at 14 locations, followed by the WAVE model and Temperature models at 8 and 6 locations, respectively during the kharif season. In the case of rabi season, the bias-corrected Temperature model appears to be accurate at more locations (21), followed by WAVE and Soygro models at 4 and 2 locations, respectively. The pooled data analysis showed the least error between estimated (uncorrected and bias-corrected) and observed hourly temperature from 04 to 08 h during kharif season while it was 03 to 08 h during the rabi season. The results of the present study indicated that Soygro and Temperature models estimated hourly temperature with better accuracy at a majority of the locations situated in the agroecological regions representing different climates and soil types. Though the WAVE model worked well at some of the locations, estimation by the PL model was not up to the mark in both kharif and rabi seasons. Hence, Soygro and Temperature models can be used to estimate hourly temperature data during both kharif and rabi seasons, after the bias correction by the Linear Regression method. We believe that the application of the study would facilitate the usage of hourly temperature data instead of daily data which in turn improves the precision in predicting phenological events and bud dormancy breaks, chilling hour requirement etc.

Pest scenario of Helicoverpa armigera (Hub.) on pigeonpea during future climate change periods under RCP based projections in India.

Gram pod borer, Helicoverpa armigera (Hub.) is the major insect pest of pigeonpea and prediction of number of generations (no. of gen.) and generation time (gen. time) using growing degree days (GDD) approach during three future climate change periods viz., Near (NP), Distant (DP) and Far Distant (FDP) periods at eleven major pigeonpea growing locations of India was attempted. Multi-model ensemble of Maximum (Tmax) and Minimum (Tmin) temperature data of four Representative Concentration Pathways viz., RCP 2.6, 4.5, 6.0 and 8.5 of Coupled Model Inter comparison Project 5 (CMIP5) models was adopted here. The increase in projected Tmax and Tmin are significant during 3 climate change periods (CCPs) viz., the NP, DP and FDP over base line (BL) period under four RCP scenarios at all locations and would be higher (4.7-5.1 °C) in RCP 8.5 and in FDP. More number of annual (10-17) and seasonal (5-8) gens. are expected to occur with greater percent increase in FDP (8 to 38%) over base line followed by DP (7 to 22%) and NP (5to 10%) periods with shortened annual gen. time (4 to 27%) across 4 RCPs. The reduction of crop duration was substantial in short, medium and long duration pigeonpeas at all locations across 4 RCPs and 3 CCPs. The seasonal no.of gen. is expected to increase (5 to 35%) with shortened gen. time (4 to 26%) even with reduced crop duration across DP and FDP climate periods of 6.0 and 8.5 RCPs in LD pigeonpea. More no. of gen. of H. armigera with reduced gen. time are expected to occur at Ludhiana, Coimbatore, Mohanpur, Warangal and Akola locations over BL period in 4 RCPs when normal duration of pigeonpeas is considered. Geographical location (66 to 72%), climate period (11 to 19%), RCPs (5-7%) and their interaction (0.04-1%) is vital and together explained more than 90% of the total variation in future pest scenario. The findings indicate that the incidence of H. armigera would be higher on pigeonpea during ensuing CCPs in India under global warming context.

PAAN/MIF nuclease inhibition prevents neurodegeneration in Parkinson's disease.

Parthanatos-associated apoptosis-inducing factor (AIF) nuclease (PAAN), also known as macrophage migration inhibitor factor (MIF), is a member of the PD-D/E(X)K nucleases that acts as a final executioner in parthanatos. PAAN's role in Parkinson's disease (PD) and whether it is amenable to chemical inhibition is not known. Here, we show that neurodegeneration induced by pathologic α-synuclein (α-syn) occurs via PAAN/MIF nuclease activity. Genetic depletion of PAAN/MIF and a mutant lacking nuclease activity prevent the loss of dopaminergic neurons and behavioral deficits in the α-syn preformed fibril (PFF) mouse model of sporadic PD. Compound screening led to the identification of PAANIB-1, a brain-penetrant PAAN/MIF nuclease inhibitor that prevents neurodegeneration induced by α-syn PFF, AAV-α-syn overexpression, or MPTP intoxication in vivo. Our findings could have broad relevance in human pathologies where parthanatos plays a role in the development of cell death inhibitors targeting the druggable PAAN/MIF nuclease.

Evaluating area-specific adaptation strategies for rainfed maize under future climates of India.

This study investigates the spatio-temporal changes in maize yield under projected climate and identified the potential adaptation measures to reduce the negative impact. Future climate data derived from 30 general circulation models were used to assess the impact of future climate on yield in 16 major maize growing districts of India. DSSAT model was used to simulate maize yield and evaluate adaptation strategies during mid (2040-69) and end-centuries (2070-99) under RCP 4.5 and 8.5. Genetic coefficients were calibrated and validated for each of the study locations. The projected climate indicated a substantial increase in mean seasonal maximum (0.9-6.0 °C) and minimum temperatures (1.1-6.1 °C) in the future (the range denotes the lowest and highest change during all the four future scenarios). Without adaptation strategies, climate change could reduce maize yield in the range of 16% (Tumkur) to 46% (Jalandhar) under RCP 4.5 and 21% (Tumkur) to 80% (Jalandhar) under RCP 8.5. Only at Dharwad, the yield could remain slightly higher or the same compared to the baseline period (1980-2009). Six adaptation strategies were evaluated (delayed sowing, increase in fertilizer dose, supplemental irrigation, and their combinations) in which a combination of those was found to be effective in majority of the districts. District-specific adaptation strategies were identified for each of the future scenarios. The findings of this study will enable in planning adaptation strategies to minimize the negative impact of projected climate in major maize growing districts of India.

Role of immunohistochemistry markers in neoplastic lung lesions.

OBJECTIVES: The objective of the evaluate was to study and determine the usefulness of immunohistochemistry (IHC) staining in neoplastic lung lesions. MATERIALS AND METHODS: We evaluated seven IHC stains in fifty lung cancers that included adenocarcinoma (AC), squamous cell carcinoma (SCC), small cell carcinoma, and carcinoid tumors. RESULTS: P63 was expressed in all the cases of SCCs and thyroid transcription factor-1 (TTF-1) was expressed in all cases of ACs. CK 5/6 was expressed in 77.77% of SCCs and CK 7 was expressed in 92.59% of ACs. Synaptophysin and chromogranin-A were expressed in 100% of neuroendocrine (NE) carcinomas. CONCLUSION: P63 and TTF-1 are sensitive markers for SCCs and ACs. Synaptophysin and Chromogranin-A are sensitive markers for NE carcinomas.

Dietary diversity scores, nutrient intakes and biomarkers vitamin B12, folate and Hb in rural youth from the Pune Maternal Nutrition Study.

Hidden hunger is widespread in India. Individual dietary diversity score (IDDS) is a measure of the nutrient adequacy of the diet. The FAO has set guidelines for the measurement of dietary diversity: the IDDS and the minimum dietary diversity score for women (MDD-W) to assess nutritional deficiency, but validation against nutritional biomarkers is required. Using available data among rural youth (17 years) from the Pune Maternal Nutrition Study, the validity of DDS was assessed to measure deficiencies of vitamin B12, folate and Hb. Of the 355 boys and 305 girls, 19 % were classified as underweight, 57 % as vitamin B12 deficient (<150 pmol/l) and 22 % as anaemic (<120/130 g/l). Cereals, legumes and 'other-vegetables' were the most frequently consumed foods. More boys than girls consumed milk, flesh, eggs and micronutrient-dense foods. Median IDDS of 4 (interquartile range (IQR) 3-4) and MDD-W of 6 (IQR 5-7) were low. Youth with vitamin B12 deficiency had a higher likelihood of an IDDS ≤ 4 (1·89; 95 % CI 1·24, 2·87) or an MDD-W ≤ 5 (1·40; 95 % CI 1·02, 1·94). Youth with anaemia were more likely to have an IDDS ≤ 4 (1·76; 95 % CI 1·01, 3·14) adjusted for socio-economic scores, BMI, energy intake and sex. Folate deficiency was low (3 %) and was not associated with either score. Youth with lowest plasma vitamin B12 and Hb infrequently or never consumed dairy products/non-vegetarian foods. These rural Indian youth were underweight, had low DDS and consumed foods low in good-quality proteins and micronutrients. Associations of DDS with circulating micronutrients indicate that DDS is a valid measure to predict vitamin B12 deficiency and anaemia.

Pest scenario of Spodoptera litura (Fab.) on groundnut under representative concentration pathways (RCPs) based climate change scenarios.

Multi-model ensemble of Maximum (Tmax) and Minimum (Tmin) temperature data of four Representative Concentration Pathways viz., RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5 of Coupled Model Intercomparison Project 5 (CMIP5) models were generated for ten major groundnut growing locations of the India to predict the number of generations of Spodoptera litura (Fab.) using Growing Degree Days approach during three future climate viz., Near (NF), Distant (DF) and Very Distant (VDF) periods and were compared over 1976-2005 baseline period (BL). Projections indicate significant increase in Tmax (0.7-4.7 °C) and Tmin (0.7-5.1 °C) in NF, DF and VDF periods under the four RCP scenarios at the ten groundnut growing locations. Higher percent increase of the number of generations of S. litura was predicted to occur in VDF (6-38%) over baseline, followed by DF (5-22%) and NF (4-9%) periods with reduction of generation time (5-26%) across the four RCP scenarios. Reduction of crop duration was higher (12-22 days) in long duration groundnut than in medium and short duration groundnut. Decrease in crop duration was higher in VDF (12.1-20.8 days) than DF (8.26-13.15 days) and NF (4.46-6.15 days) climate change periods under RCP 8.5 scenario. Increase in number of generations of S. litura was predicted even with altered crop duration of groundnut. Among locations, more number of generations of S. litura with reduced generation time are likely at Vridhachalam and Tirupathi locations. Geographical location (74-77%) and climate period (15-19%), together explained over 90 percent of the total variation in the number of generations and generation time of S. litura. These findings suggest that the incidence of S. litura on groundnut could be higher in future.

A two-year hospital based study of Lung Cancer with reference to Histological subtypes, Demograhpics, risk factors and presentng stage

Lung cancer is one of the most common cause of mortality, highly attributed to an increase in tobacco use/ cigarette smoking. It ranks amongst the top 3 causes of cancer in Trinidad and Tobagonian men. The objective of this study is to the investigate the prevalence of Lung cancer in Trinidad and Tobago, its histological subtypes, demographics, predisposing risk factors and presenting stage. Additionally, comparison is made between current Lung cancer trends and those identified from previous studies. Our current findings is a more accurate representation of local trends, which can now provide foundational data that can be used to implement better approaches in the improvement of Lung cancer care in Trinidad and Tobago.

Cold Plasma: Clean Technology to Destroy Pathogenic Micro-organisms.

Atmospheric pressure cold plasma is a promising technology in fighting pathogenic micro-organisms. In times of Covid-19 pandemic, it was decided to modify two types of cold plasma devices to study their effectiveness in the killing of pathogenic micro-organisms. These studies have shown that both the devices are efficient in this purpose. While pencil like microwave based device can destroy Aeromonas bacteria and its bacteriophage from 6 cm distance in 2 min, the larger (~ 40 cm2) RF plasma based device could do the similar killing ability for the larger possible area in 4 min. Optical Emission Spectroscopy (OES) studies revealed that both these devices produce OH radicals which helped in the destruction of both bacteria and its bacteriophage. With suitable modifications, these devices, especially the larger area device may even be implemented for the elimination of Covid-19 affected wards of hospital without using any sensitive chemical process.

A miniaturized electrochemical platform with an integrated PDMS reservoir for label-free DNA hybridization detection using nanostructured Au electrodes.

We report the fabrication and characterization of a miniaturized electrochemical platform for the label-free detection of DNA hybridization. The proposed platform is fabricated using microfabrication and electrodeposition techniques. Comprising a Ti working electrode with electrodeposited Au nanostructures, and Pt/Au pseudo-reference and counter electrodes, the device accounts for a limit of detection of 0.97 fM and a sensitivity of 20.78 (µA µM-1) cm-2 with respect to Dengue virus specific consensus primer detection in the range of 10 fM-1 µM. Here, the incorporation of nanostructured Au in the active sensing area not only enhances the current response by increasing the overall surface area, but it also facilitates facile probe DNA immobilization by gold-thiol self-assembly. We have used differential pulse voltammetry analysis in this study to monitor the changes in reaction kinetics with respect to target hybridization. Furthermore, the evaluation of reproducibility of the biosensor and its selectivity against interference has yielded acceptable outcomes. Additionally, in order to evaluate the system's selectivity, we have successfully distinguished PCR amplified wild type and mutant target DNAs corresponding to the BRCA1 specific gene. Here, the mutant and the wild type target DNAs differ by a two base deletion, and the fact that the system is able to differentiate even such minute dissimilarities under hybridization conditions is indicative of its superior performance.

Discovery of a Potent GLUT Inhibitor from a Library of Rapafucins by Using 3D Microarrays.

Glucose transporters play an essential role in cancer cell proliferation and survival and have been pursued as promising cancer drug targets. Using microarrays of a library of new macrocycles known as rapafucins, which were inspired by the natural product rapamycin, we screened for new inhibitors of GLUT1. We identified multiple hits from the rapafucin 3D microarray and confirmed one hit as a bona fide GLUT1 ligand, which we named rapaglutin A (RgA). We demonstrate that RgA is a potent inhibitor of GLUT1 as well as GLUT3 and GLUT4, with an IC50 value of low nanomolar for GLUT1. RgA was found to inhibit glucose uptake, leading to a decrease in cellular ATP synthesis, activation of AMP-dependent kinase, inhibition of mTOR signaling, and induction of cell-cycle arrest and apoptosis in cancer cells. Moreover, RgA was capable of inhibiting tumor xenografts in vivo without obvious side effects. RgA could thus be a new chemical tool to study GLUT function and a promising lead for developing anticancer drugs.

Correction: Synthesis and biological evaluation of pyrazolo-triazole hybrids as cytotoxic and apoptosis inducing agents.

Correction for 'Synthesis and biological evaluation of pyrazolo-triazole hybrids as cytotoxic and apoptosis inducing agents' by T. Srinivasa Reddy et al., Org. Biomol. Chem., 2015, 13, 10136-10149.

Synthesis and biological evaluation of new bisindole-imidazopyridine hybrids as apoptosis inducers.

A series of diindolylmethanes (5a-t) were designed, synthesized, and examined for their cytotoxicity against four human cancer cell lines like prostate (DU-145), lung (A549), breast (MCF-7) and cervical cancer (HeLa). These results revealed that among all the hybrids, two (5k and 5r) were identified and exhibited significant cytotoxic effect against A549 cancer cells with IC50 values of 1.65 ±â€¯0.3 and 1.80 ±â€¯0.8 µM respectively. To investigate the reasons for the cytotoxic activity, the conventional biological assays were carried out with 5k and 5r on the A549 cancer cells. Both hybrids led to the arrest of A549 cell lines at the G2/M phase of the cell cycle and strongly induced apoptosis. Further the apoptotic effects of 5k and 5r were confirmed by ROS, annexin-V FITC, and mitochondrial membrane potential. Moreover, structure-activity relationships were elucidated with various substitutions on these hybrids.

Supported liquid extraction and LC-MS-MS determination of iloperidone and olanzapine in rat plasma: Application to a pharmacokinetic study.

A sensitive, selective rapid bioanalytical assay method was developed and quantification of iloperidone (ILP) and olanzapine (OLZ) in rat plasma was done by mass spectrometry. Systematic sample preparation and extraction procedure were carried out by supported liquid extraction using dichloromethane to extract both the eluents (ILP and OLZ) from rat plasma samples. The extorted samples were injected on a selective Waters XTerra® C18 reverse-phase bonded column (250 × 4.6 mm i.d., 5 µm) using acetonitrile and 15 mM ammonium formate containing 0.05% trifluoroacetic acid (60:40 v/v) for isocratic elution mode and detected by mass spectrometry. Calibration curves were drawn with the respective assay statistical data and showed linear regression coefficients greater than 0.9996 over the concentration ranges 2-5,000 ng/mL for ILP and OLZ, respectively. The absolute mean recoveries were found to be in the replicate range of 87.12-94.47%, respectively. The obtained results by the method revealed good intra and interday assay performance in terms of 1.70-5.90% precision and 0-5% accuracy. The validated bioassay method has been successfully applied to the pharmacokinetics in rats.

Prevalence, clinical features, and diagnosis of Trichomonas vaginalis among female STI clinic attendees in Trinidad.

BACKGROUND: Trichomonas vaginalis (TV) is one of the most common pathogens causing sexually transmitted infections (STIs) in both men and women. Since there are no accurate prevalence data available on TV infection among women for Trinidad and Tobago and in the Caribbean region, there is a great need for research to study the dynamics of the infection and its transmission. OBJECTIVES: To determine the prevalence and diagnose TV infection in women attending the STI clinic and to provide recommendations for control and prevention of trichomoniasis in the community. STUDY DESIGN: A cross-sectional study was designed after obtaining the informed consent. Following a routine clinical examination, vaginal swabs were collected - one for wet mount preparation, one for InPouch culture, and other two for OSOM rapid test/and fluorescent antibody testing. Cotton swabs and Dacron swabs were used for testing. RESULTS: A prevalence of 16% of trichomoniasis out of 422 females was recorded. In all, 65 (65%) were in the age range of 15-29 years and peak of 30% in the age group of 20-24 years. Vaginal discharge was a common complaint (83%); 75.6% had foul odor and only 9.8% had typical fishy odor. The majority of them (87%) had whitish-yellow colored discharge. CONCLUSION: Prevalence of trichomoniasis is significant in the female population attending STI clinic. Targeting high-risk age group between 15 and 29 years for control and prevention would be beneficial. Prompt and accurate diagnosis using appropriate laboratory test is recommended.

Design and synthesis of 1,2,3-triazolo linked benzo[d]imidazo[2,1-b]thiazole conjugates as tubulin polymerization inhibitors.

1,2,3-Triazolo linked benzo[d]imidazo[2,1-b]thiazole conjugates (5a-v) were designed, synthesized and evaluated for their cytotoxic potency against some human cancer cell lines like DU-145 (prostate), HeLa (cervical), MCF-7 (breast) HepG2 (liver) and A549 (lung). Preliminary results revealed that some of these conjugates like 5f and 5k exhibited significant antiproliferative effect against human breast cancer cells (MCF-7) with IC50 values of 0.60 and 0.78µM respectively. Flow cytometric analysis of the cell cycle demonstrated an increase in the percentage of cells in the G2/M phase which was further authenticated by elevation of cyclin B1 protein levels. Immunocytochemistry revealed loss of intact microtubule structure in cells treated with 5f and 5k, and western blot analysis revealed that these conjugates accumulated more tubulin in the soluble fraction. Moreover, the conjugates caused apoptosis of the cells that was confirmed by mitochondrial membrane potential and Annexin V-FITC assay. Molecular docking studies indicated that these conjugates occupy the colchicine binding site of the tubulin protein.

2-Arylaminobenzothiazole-arylpropenone conjugates as tubulin polymerization inhibitors.

A new series of 2-arylaminobenzothiazole-arylpropenone conjugates 5-6(a-r) was designed, synthesized and investigated for their cytotoxic potency against the various human cancer cell lines. Most of these conjugates exhibited cytotoxic activity and inhibited in vitro tubulin polymerization effectively. Conjugates 5d and 6d cause cell cycle blocks in the G2/M phase in HeLa cells and treatments with 5d and 6d manifested increased mRNA and protein levels of the G2/M marker, cyclin B1. Immunocytochemistry revealed loss of intact microtubule structure in cells treated with 5d and 6d. Western blot analysis revealed that these conjugates accumulate more tubulin in the soluble fraction. Moreover, the triggering of apoptotic cell death after mitotic arrest was investigated by studying their effect on Hoechst staining, mitochondrial membrane potential, ROS generation.

Indian summer heat wave of 2015: a biometeorological analysis using half hourly automatic weather station data with special reference to Andhra Pradesh.

Heat wave is a hazardous weather-related extreme event that affects living beings. The 2015 summer heat wave affected many regions in India and caused the death of 2248 people across the country. An attempt has been made to quantify the intensity and duration of heat wave that resulted in high mortality across the country. Half hourly Physiologically Equivalent Temperature (PET), based on a complete heat budget of human body, was estimated using automatic weather station (AWS) data of four locations in Andhra Pradesh state, where the maximum number of deaths was reported. The heat wave characterization using PET revealed that extreme heat load conditions (PET >41) existed in all the four locations throughout May during 2012-2015, with varying intensity. The intensity and duration of heat waves characterized by "area under the curve" method showed good results for Srikakulam and Undi locations. Variations in PET during each half an hour were estimated. Such studies will help in fixing thresholds for defining heat waves, designing early warning systems, etc.

Design and synthesis of imidazo[2,1-b]thiazole linked triazole conjugates: Microtubule-destabilizing agents.

A series of imidazo[2,1-b]thiazole linked triazole conjugates were synthesized by using Huisgen 1,3-dipolar cyclo-addition reaction (click chemistry approach) and evaluated for their antiproliferative activity against some human cancer cell lines like, HeLa (cervical), DU-145 (prostate), A549 (lung), MCF-7 (breast) and HepG2 (liver). Among them, Conjugates 4g and 4h demonstrated a significant antiproliferative effect against human lung cancer cells (A549) with IC50 values of 0.92 and 0.78 µM respectively. Flow cytometric analysis revealed that these conjugates induced cell cycle arrest in G2/M phase in A549 lung cancer cells. The tubulin polymerization assay and immunofluorescence analysis showed that these conjugates effectively inhibit microtubule assembly in cell free and cell based (A549) experiment respectively. Moreover, the apoptosis inducing properties were evaluated by Hoechst staining, mitochondrial membrane potential and Annexin V-FITC assay. Further, western blot analysis was performed for proapoptotic protein Bax and antiapoptotic protein Bcl-2 and the results demonstrated that there was up regulation of Bax and down regulation of Bcl-2 suggesting that these compounds induced apoptosis in human lung cancer cells, A549.