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The versatility of aza- and oxa-heterocyclic compounds has garnered significant attention in recent times. A large number of currently approved pharmaceutical products include nitrogen- and oxygen-containing heterocycles. Recent nanotechnological developments have propelled an upsurge in the applications of nanocatalysis for heterocyclic synthesis. Metal nanoparticles (MNPs) have emerged as promising catalysts for the synthesis of aza- and oxa-heterocycles owing to their unique physicochemical properties. Various MNPs including gold, silver, nickel and palladium have been evaluated for their catalytic activities in different reaction types, including cyclisation, coupling, hydrogenation and oxidative transformations. The MNPs have exhibited remarkable catalytic efficiency when utilised under optimal conditions. These catalysts have showcased high reusability and recyclability, yielding satisfactory amounts of the desired heterocyclic compound. The present work provides a detailed overview of recent advances in the area of MNP-assisted synthetic construction of aza- and oxa-heterocycles, published during the previous calendar year, 2022. The review serves as a valuable resource and also paves the way for future investigations in the development of novel catalytic strategies for heterocycle synthesis. 1 Introduction 2 Nanocatalysis 3 Aza- and Oxa-Heterocycle Synthesis Catalysed by MNPs 3.1 AuNPs 3.2 CuNPs 3.3 CoNPs 3.4 FeNPs 3.5 NiNPs 3.6 PdNPs 3.7 PtNPs 3.8 SiNPs 3.9 ZnNPs 3.10 Bimetallic NPs 3.11 Other MNPs 4 Summary and Outlook [ABSTRACT FROM AUTHOR]

The DNA repair process protects the cells from DNA damaging agent by multiple pathways. Majority of the cancer therapy cause DNA damage which leads to apoptosis. The cell has natural ability to repair this damage which ultimately leads to development of resistance of drugs. The key enzymes involved in DNA repair process are poly(ADP-ribose) (PAR) and poly(ADP-ribose) polymerases (PARP). Tumor cells repair their defective gene via defective homologues recombination (HR) in the presence of enzyme PARP. PARP inhibitors inhibit the enzyme poly(ADP-ribose) polymerases (PARPs) which lead to apoptosis of cancer cells. Current clinical data shows the role of PARP inhibitors is not restricted to BRCA mutations but also effective in HR dysfunctions related tumors. Therefore, investigation in this area could be very helpful for future therapy of cancer. This review gives detail information on the role of PARP in DNA damage repair, the role of PARP inhibitors and chemistry of currently available PARP inhibitors.

Carrot is an important vegetable crop worldwide valued for its fleshy edible roots of varied colours. Owing to its highly cross-pollinated nature and small flower size, cytoplasmic male sterility (CMS) is being utilized for hybrid development. Among different types of male sterility, petaloid CMS is widely used for hybrid carrot breeding globally. This study aimed to develop selection criteria for parents in developing heterotic F 1 hybrids using CMS lines. A large number of agro-morphological traits and Simple Sequence Repeats (genomic-SSRs) were used to assess the diversity among parental lines. We developed 60 F 1 hybrids by crossing four petaloid CMS lines and 15 testers in line × tester mating design and evaluated them in replicated randomized block design trial for four vegetative and 11 economic traits. The mean squares of all the traits in line × tester interactions were significant. The estimates of genetic components of variance indicated predominance of non-additive gene action except for root maturity, root length and core diameter. The hybrids with highest per se performance also had significant positive specific combining ability effects. The root yield and root weight showed highest heterosis percentage (33%). The best performing heterotic hybrids were DCatH-5392, DCatH-700 and DCatH-9892. Correlation between genetic distance and relative heterosis of economic traits indicated no significant association and thus genetic distance could not be used to predict heterosis. As most of the yield-related traits were controlled by non-additive gene action, heterosis breeding could be potentially used along with combining ability analysis to reduce time in selection of best parents and crosses in tropical carrot. [ABSTRACT FROM AUTHOR]

Applying kinetics principles to drug degradation studies helps in determine the expiration dates of drugs and formulations. An accurate, precise and sensitive stability‐indicating high‐performance liquid chromatographic method was developed and validated to study the degradation kinetics of Dapagliflozin (DGZ). DGZ was degraded under different stress conditions and degraded samples were chromatographed on C18 (150 mm × 4.6 mm, 5 µm) column, separated using solvent system acetonitrile and 0.01% triethylamine solution (pH 5 adjusted with orthophosphoric acid) in a ratio of 70:30 v/v and detected at 270 nm. The design of experiments (DOEs) was applied to study the degradation kinetics of DGZ in the oxidative medium. The effect of temperature and concentration of H2O2 on the order of reaction and % degradation was studied at three levels using a full factorial design. The linearity range for DGZ was 1–60 µg/mL (correlation coefficient = 0.9996) with an average recovery of 99.98%. The limit of detection (LOD) and limit of quantitation (LOQ) for DGZ were 0.07 and 0.22 µg/mL, respectively. Degradation of DGZ in the oxidative medium was found to follow first‐order kinetics. Contour plots have been generated to predict the degradation rate constant and % degradation of DGZ in different combinations of temperature and concentration of H2O2 using Design Expert software (Trial version). [ABSTRACT FROM AUTHOR]

Due to alarming outbreak of pandemic COVID‐19 in recent times, there is a strong need to discover and identify new antiviral agents acting against SARS CoV‐2. Among natural products, lignan derivatives have been found effective against several viral strains including SARS CoV‐2. Total of twenty‐seven reported antiviral lignan derivatives of plant origin have been selected for computational studies to identify the potent inhibitors of SARS CoV‐2. Molecular docking study has been carried out in order to predict and describe molecular interaction between active site of enzyme and lignan derivatives. Out of identified hits, clemastatin B and erythro‐strebluslignanol G demonstrated stronger binding and high affinity with all selected proteins. Molecular dynamics simulation studies of clemastin B and savinin against promising targets of SARS CoV‐2 have revealed their inhibitory potential against SARS CoV‐2. In fine, in‐silico computational studies have provided initial breakthrough in design and discovery of potential SARS CoV‐2 inhibitors. [ABSTRACT FROM AUTHOR]

A combination of Ofloxacin, Tinidazole, Terbinafine hydrochloride, and Clobetasol propionate is used for treatment, control, prevention, and improvement of bacterial and fungal skin infections. Two chromatographic methods (HPLC and HPTLC) were developed for the quantitative determination of these four drugs in their combined topical formulation. The HPLC method employed a C18 (250 × 4.6 mm, 5 μ) column as a stationary phase and acetonitrile: 0.1% triethylamine (pH 3.5) with gradient elution as mobile phase. The chromatographic separation in HPTLC was carried out on precoated silica 60F254 plates using toluene:ethyl acetate:methanol:triethylamine:formic acid (5:4:1:0.3:0.3 v/v/v/v/v) as mobile phase. Both methods used 238 nm as detection wavelength and were able to separate all four drugs with resolved and sharp peaks. Developed methods were validated as per ICH Q2(R1) guidelines. Both methods were found to be linear in selected ranges (r2 > 0.998), precise (RSD < 2%), accurate (recovery > 99.5%), sensitive and specific for quantitation of all four drugs. Validated methods were successfully applied for the quantitative determination of four drugs in the cream formulation and assay results were found to be in good agreement with the stated amount of each drug. Assay results were statistically compared (t-test) and no significant difference was observed (p > 0.05) between the results obtained by both methods. [ABSTRACT FROM AUTHOR]

Local plant species have been in use in variety of ethnomedicinal practices from the time immemorial among the people of various communities for treating various human diseases. This paper reports about the plant species used by Adi community in curing various human diseases and ailments. A study was conducted during 2008-2009 and further refined in succeeding years with the 12 purposively selected traditional knowledge holders (TKHs) of Adi tribe of East Siang district, Arunachal Pradesh, India. Data were collected using combined approaches of personal interview, participant observations and transect walks. It was observed that with Shannon-Weaver diversity index 2.73, there were 39 local plant species belonging to 25 plant families and used as ethnomedicinal practices by the TKHs. Most of the species (17) were used by Adi TKHs with their green leaf parts followed by root and fruits (5 each) to develop ethnomedicinal formulations. Out of these, several species namely Leucas aspera (Willd.) Link.; Plumeria rubra L.; Catharanthus roseus (L.) G. Don; Solanum torvum Swartz; Solanum khasianum C.B. Clarke; Oroxylum indicum (L.) Benth.ex Kurze; and Tinospora cordifolia (Thunb.) Miers) were found in use by Adis against asthma, bronchitis, cough, sinusitis, diabetes, malaria, typhoid and jaundice. The Adi TKHs maintain a rich cultural ethics, govern by their own world-view in continuing ethnomedicinal practices, and harvesting the species from various land use systems with the aim to sustain biodiversity and associated practices. The key findings indicated that, plant species used as ethnomedicines for some of the diseases and ailments by the Adi TKHs, can be undertaken for the long-term trial to find some natural remedies against few human diseases, including search of immune enhancer against COVID-19, provided TKHs of Adi community are partnered in ethically and culturally appropriate manner. [ABSTRACT FROM AUTHOR]

This study reports the Brokpa herder's knowledge and strategies of using and managing rangeland ecosystems of Tawang and West Kameng districts of Arunachal Pradesh. Study was conducted with 60 herders in 6 villages dominated by Borkpa community. Based on conventional and participatory socio-ecological research methods, the results indicated that, traditional yak-herding system play a pivotal role in maintaining the culture and economic insurance to Brokpa community. Burning activates the growth of gasses and vegetation. In the traditional seasonal migratory system, yak grazing is done in the alpine pastures for four months (June to September) while at middle hills (3,500 - 4,500 m amsl) grazing takes place from March to May, as the yaks migrate up to the high pastures and again on their return during October and November. The winter (December-February) is spent on grazing at lower altitude (< 3000 m amsl). On a specified barter point in the hills, exchange of yak and sheep milk products with grains (maize, barley, buckwheat, finger millet and wheat) are done with villagers. The compatibility of yak based livestock production systems with existing ecosystem diversities and lifestyle of Brokpas are intricately related with their livelihood, and ensure the sustainable use of rangelands. Yak husbandry of Brokpa faces stress caused by climate variability and other environmental factors. Such stresses have caused in declining the yak population and weakened the dynamics of rangeland ecosystems, although, Brokpa are trying to adapt with local adaptive strategies, To sustain yak based livelihoods and rangeland ecosystems, integration of informal and formal knowledge is urgently required to co-produce adaptive knowledge. [ABSTRACT FROM AUTHOR]

Objectives: The aim of the present work was to synthesize a novel series of pyrazolo[3,4-d] pyrimidin-4(5H)-one derivatives and evaluate their in vitro antimicrobial activity. Methods: Cyclization of an ortho-amino ester of 1-(2,4-dinitrophenyl)pyrazole with various aliphatic/aromatic nitriles under different reaction conditions such as conventional and microwave assisted synthesis, provided pyrazolo[3,4-d] pyrimidin-4(5H)-one derivatives. All the synthesized compounds were evaluated in vitro for their antimicrobial activity against selected bacteria and fungi by agar well diffusion method. Results: All newly synthesized compounds were characterized using spectral and elemental analysis. Compounds 2e, 2f, and 2g showed significant antimicrobial activity as compared to standard drugs used. Conclusion: The newly synthesized compounds could be useful templates for the design and optimization of more active analogs as a possible antimicrobial agent. [ABSTRACT FROM AUTHOR]

This is the first report on increasing yield and nutritional content of snake melon (Cucumis melo L. var. flexuosus) by exploiting intraspecific genetic variation of genetically diverse melons. Inbred snake melon 'Punjab Long melon 1' (PLM1) was hybridized with five genetically diverse inbred melons: KP 7 (var. momordica), AM 72 (var. acidulus), 'Arya 1' (var. chate), 04-02 (var. tibish) and 'Punjab Wanga' (unknown botanical variety). The parents and hybrids were evaluated at three locations for nine traits. Hybrids PLM1 X 04-02 and PLM1 X 'Punjab Wanga' exhibited significant (P0.05) heterosis for the number of marketable fruits per plant, and ascorbic acid and carotenoid contents of marketable fruits. [ABSTRACT FROM AUTHOR]

We present here the first comprehensive genetic characterization of snapmelon landraces from the humid tropics of eastern India. The genetic diversity among 42 snapmelon landraces collected from four agro-ecological regions of eastern India (eight agro-ecological subregions) was assessed by measuring variation at 16 simple sequence repeat (SSR) marker loci, at various traits including plant habit and fruit type, yield (two associated traits), disease resistance and biochemical composition (total soluble solids, ascorbic acid, carotenoids and titrable acidity). Differences between accessions were observed in a number of plant and fruit traits. Snapmelon germplasm with high acidity, elevated carotenoid content and resistance to cucumber mosaic virus were identified in the collection. The SSR analysis indicated that there is a high level of genetic variability within snapmelon germplasm. Comparison of the genetic variability between snapmelons of eastern India and melons from north, south and central regions of India and reference accessions of melon from Spain, France, Japan, Korea, Maldives, Iraq, Zambia, Israel using SSRs showed that Indian snapmelon germplasm is not closely related to melon accessions from other parts of the world and that there are regional differences between Indian melon accessions. Eastern India snapmelon has unique traits, so it is important that more germplasm from this region is sampled and preserved. [ABSTRACT FROM AUTHOR]

Ash gourd or wax gourd [Benincasa hispida (Thunb.) Cogn.], belonging to the family Cucurbitaceae, is an under-exploited vegetable in spite of having considerable economic and medicinal importance. Very little information is available on the genetic diversity and exploitation of heterosis in this crop. In the present study, nine inbred lines of ash gourd were crossed to produce all (72) possible F1 hybrids, including reciprocals, which were evaluated along with the nine parents for 13 growth- and yield-related traits and 14 quality traits, in a replicated field trial. A high level of heterosis was observed among the hybrids for most of the traits examined, including iron and zinc content. Significant reciprocal differences in heterosis were observed. The inbred lines were analysed using 130 RAPD primers, of which 26 were informative and amplified 163 DNA marker bands. A total of 47 polymorphic bands were obtained with a mean of 1.8 per primer which, in combination, discriminated all the inbreds from each other. Pair-wise genetic distance measurements ranged from 0.056 to 0.179, suggesting a narrow genetic base for the inbreds. Although the results indicated significant positive correlations of genetic distance with hybrid performance and heterosis, the magnitudes of the correlations were not high enough to be of predictive value. [ABSTRACT FROM AUTHOR]

Review: 75 refs. [ABSTRACT FROM AUTHOR]

Background: Nitrosamine impurities are potent carcinogens in animals and probable carcinogens in humans. There is a need for effective analytical methods to detect and identify various nitrosamine impurities, and to develop rapid solutions to ensure the safety and quality of the drugs. Objective: A liquid chromatographic method was developed for estimation of six nitrosamine impurities in valsartan. Methods: The developed method employed: a C18 (250 x 4.6mm, 5 μm) column as a stationary phase; a combination of acetonitrile, water (pH 3.2 adjusted with formic acid), and methanol with gradient elution as mobile phase; and 228nm as the detection wavelength. The developed method was validated as per International Conference on Harmonization Q2(R1) guidelines. The method was successfully applied to estimate six nitrosamine impurities in valsartan API (active pharmaceutical ingradient) and formulation (tablets). Results: The method was able to separate each impurity and valsartan with resolved and sharp peaks. Results indicated that the developed method is linear in selected ranges (coefficient of regressions >0.9996), precise (RSD <2%), accurate (recovery in a range of 99.02-100.16%), sensitive (low detection and quantitation limits), and specific for estimation of each impurity in valsartan. Assay results were in agreement with the spiked amount of each impurity. Conclusion: The developed method can be applied for simultaneous estimation of six nitrosamine impurities in valsartan raw material, tablets, and fixed dose combination at very low levels. Highlights: Development, validation, and application of a HPLC method for the estimation of six nitrosamine impurities in valsartan API and formulation samples. [ABSTRACT FROM AUTHOR]