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Curcumin isoxazole (CI) and Curcumin pyrazole (CP), the diketo modified derivatives of Curcumin (CU) are metabolically more stable and are being explored for pharmacological properties. One of the requirements in such activities is their interaction with circulatory proteins like human serum albumin (HSA). To understand this, the interactions of CI and CP with HSA have been investigated employing absorption and fluorescence spectroscopy and the results are compared with that of CU. The respective binding constants of CP, CI and CU with HSA were estimated to be 9.3×10 5 , 8.4×10 5 and 2.5×10 5 M -1 , which decreased with increasing salt concentration in the medium. The extent of decrease in the binding constant was the highest in CP followed by CI and CU. This revealed that along with hydrophobic interaction other binding modes like electrostatic interactions operate between CP/CI/CU with HSA. Fluorescence quenching studies of HSA with these compounds suggested that both static and dynamic quenching mechanisms operate, where the contribution of static quenching is higher for CP and CI than that for CU. From fluorescence resonance energy transfer studies, the binding site of CU, CI and CP was found to be in domain IIA of HSA. CU was found to bind in closer proximity with Trp214 as compared to CI and CP and the same was responsible for efficient energy transfer and the same was also established by fluorescence anisotropy measurements. Furthermore docking simulation complemented the experimental observation, where both electrostatic as well as hydrophobic interactions were indicated between HSA and CP, CI and CU. This study is useful in designing more stable CU derivatives having suitable binding properties with proteins like HSA., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Hispolon (HS), a natural polyphenol found in medicinal mushrooms, and its isoxazole (HI) and pyrazole (HP) derivatives have been examined for free radical reactions and in vitro antioxidant activity. Reaction of these compounds with one-electron oxidant, azide radicals ([Formula: see text]) and trichloromethyl peroxyl radicals ([Formula: see text]), model peroxyl radicals, studied by nanosecond pulse radiolysis technique, indicated formation of phenoxyl radicals absorbing at 420 nm with half life of few hundred microseconds (μs). The formation of phenoxyl radicals confirmed that the phenolic OH is the active centre for free radical reactions. Rate constant for the reaction of these radicals with these compounds were in the order k HI ≅ k HP  >   k HS . Further the compounds were examined for their ability to inhibit lipid peroxidation in model membranes and also for the scavenging of 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical and superoxide ([Formula: see text]) radicals. The results suggested that HP and HI are less efficient than HS towards these radical reactions. Quantum chemical calculations were performed on these compounds to understand the mechanism of reaction with different radicals. Lower values of adiabatic ionization potential (AIP) and elevated highest occupied molecular orbital (HOMO) for HI and HP compared with HS controlled their activity towards [Formula: see text] and [Formula: see text] radicals, whereas the contribution of overall anion concentration was responsible for higher activity of HS for DPPH, [Formula: see text], and lipid peroxyl radical. The results confirm the role of different structural moieties on the antioxidant activity of hispolon derivatives.

A combined methodology involving gamma and pulse radiolysis, product analysis and toxicity studies has been adopted to comprehend the degradation process of a model hydrophobic azo dye, 1-phenylazo-2-naphthol, emphasizing the role of the surfactant, which is an integral part of textile waste. Two new and important findings are underlined in this article. The first is the direct attestation of the hydrazyl radical-parent adduct, formed in the reaction of the dye with e(-)aq followed by protonation and subsequent addition to the unreacted dye molecule. This has been confirmed from concentration dependent studies. Secondly, we have clearly shown that in the reaction of hydroxyl radical with the dye in Triton X-100 media, the initially produced TX radicals cause reductive degradation of the dye. Identification and detailed analysis of HPLC and GCMS data reveals that similar products are formed in both the reactions of e(-)aq and OH radicals. Moreover, the cytotoxicity of 10(-4)moldm(-3) dye was found to be reduced significantly after irradiation. Thus, the present study not only depicts new pathways for the degradation of hydrophobic azo dye, but also demonstrates the role of a surfactant in the entire process., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Many pyrromethene (PM) dyes have been shown to outperform established rhodamine dyes in terms of laser efficiency in the green-yellow spectral region, but their rapid photochemical degradation in commonly used ethanol or methanol solvents continues to limit its use in high average power liquid dye lasers. A comparative study on narrowband laser efficiency and photostability of commercially available PM567 and PM597 dyes, using nonpolar n-heptane and 1,4-dioxane and polar ethanol solvents, was carried out by a constructed pulsed dye laser, pumped by the second harmonic (532 nm) radiation of a Q-switched Nd:YAG laser. Interestingly, both nonpolar solvents showed a significantly higher laser photostability (∼100 times) as well as peak efficiency (∼5%) of these PM dyes in comparison to ethanol. The different photostability of the PM dyes was rationalized by determining their triplet-state spectra and capability to generate reactive singlet oxygen (O 2 1) by energy transfer to dissolved oxygen in these solvents using pulse radiolysis. Heptane is identified as a promising solvent for these PM dyes for use in high average power dye lasers, pumped by copper vapor lasers or diode-pumped solid-state green lasers.

The reactions of (•)OH and O(•-), with thymol, a monoterpene phenol and an antioxidant, were studied by pulse radiolysis technique and DFT calculations at B3LYP/6-31+G(d,p) level of theory. Thymol was found to efficiently scavenge OH radicals (k = 8.1 × 10(9) dm(3) mol(-1) s(-1)) to produce reducing adduct radicals, with an absorption maximum at 330 nm and oxidizing phenoxyl radicals, with absorption maxima at 390 and 410 nm. A major part of these adduct radicals was found to undergo water elimination, leading to phenoxyl radicals, and the process was catalyzed by OH(-) (or Na(2)HPO(4)). The rate of reaction of O(•-) with thymol was found to be comparatively low (k = 1.1 × 10(9) dm(3) mol(-1) s(-1)), producing H abstracted species of thymol as well as phenoxyl radicals. Further, these phenoxyl radicals of thymol were found to be repaired by ascorbate (k = 2.1 × 10(8) dm(3) mol(-1) s(-1)). To support the interpretation of the experimental results, DFT calculations were carried out. The transients (both adducts and H abstracted species) have been optimized in gas phase at B3LYP/6-31+G(d,p) level of calculation. The relative energy values and thermodynamic stability suggests that the ortho adduct (C6_OH adduct) to be most stable in the reaction of thymol with OH radicals, which favors the water elimination. However, theoretical calculations showed that C4 atom in thymol (para position) can also be the reaction center as it is the main contributor of HOMO. The absorption maxima (λ(max)) calculated from time-dependent density functional theory (TDDFT) for these transient species were close to those obtained experimentally. Finally, the redox potential value of thymol(•)/thymol couple (0.98 V vs NHE) obtained by cyclic voltammetry is less than those of physiologically important oxidants, which reveals the antioxidant capacity of thymol, by scavenging these oxidants. The repair of the phenoxyl radicals of thymol with ascorbate together with the redox potential value makes it a potent antioxidant with minimum pro-oxidant effects.

Bodipy laser dyes are highly efficient but degrade rapidly in solution by reacting with in situ generated singlet oxygen ((1)O(2)). To increase the lasing lifetimes of these dyes, we have designed and synthesised two different congeners of the widely studied Pyrromethene 567 (PM567) by substitution at the boron centre and/or at both the boron centre and the meso position. The two new dyes showed high lasing efficiencies with increased photostability. The results of theoretical and pulse radiolysis studies revealed that the substitution at the boron centre reduced the (1)O(2) generation capacity of these dyes as well as their rate of reaction with (1)O(2), thereby enhancing their lifetimes even under lasing conditions., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Complexes of the type [Co(pic)(2)(LL)], where pic = picolinate; LL = (H(2)O)(2) (1), 2,2'-bipyridine (bpy) (2), 1,10-phenanthroline (phen) (3) and dipyrido[3,2-a:2',3'-c]phenazine (dppz) (4) have been synthesized and characterized by elemental analysis, IR, UV-visible and (1)H-NMR spectroscopy. Complex 2 crystallized from a mixture of chloroform and methanol in orthorhombic crystal system, space group Iba2. Complex 3 crystallizes from chloroform in monoclinic crystal system, space group P12(1)/a1 and in a mixture of water and methanol in triclinic crystal system, space group P1. Co(II)/Co(III) oxidation potentials have been determined by cyclic voltammetry and the concomitant spectral changes measured by spectroelectrochemistry. The reactions of one electron reducing (e(-)(aq), (CH(3))(2)*COH and CO(2)(*-)) and one electron oxidizing ( OH) radicals with the above metal complexes have been studied by pulse radiolysis. The rate constants for the reaction of e(-)(aq) and *OH radicals with the complexes are of the order of 10(10) and 10(9) dm(3) mol(-1) s(-1), respectively. The reaction of hydrated electron (e(-)(aq)) with the complexes results in the formation of a ligand radical anion species which decays by either protonation of ligand or reduction of metal by intramolecular electron transfer resulting in cobalt(I) species. The reaction of *OH radical forms the OH-adducts of the ligand.

Comparative studies on free radical scavenging by isomers of hydroxybenzyl alcohols (HBAs) were carried out to understand the molecular mechanisms involved in the antioxidant action. Using rat liver mitochondria as model systems, we have examined the radioprotective and antioxidant effects of hydroxybenzyl alcohols. Apart from their ability to scavenge free radicals and ferric reducing power, HBAs have shown good protection against radiation and oxidative stress. Using peroxyl radicals as initiator of reactive oxygen species (ROS), studies were carried out to evaluate antioxidant properties of HBAs against rat liver mitochondrial membrane components such as lipid and protein. Our results show that HBAs are potent inhibitor of lipid peroxidation and protein oxidation thus suggesting their role as free radical scavengers. In the presence of HBAs, restoration of depleted activity of Mn-SOD has also been investigated. In the presence of 2-hydroxybenzyl alcohol (2-HBA) complete restoration in the activity of Mn-SOD was observed on exposure to 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH). Free radical scavenging ability of HBAs were found to be comparable to alpha tocopherol. Pulse radiolysis technique has been used to study the reactions of HBAs with various biologically relevant reactive species such as hydroxyl radical (OH) and trichloromethyl peroxyl radical (CCl3O2). HBAs could scavenge OH radical giving initially OH-adducts which in turn decays to phenoxyl radicals. Reactions of phenoxyl radicals of HBAs with ascorbic acid have been also studied. Redox potential of HBAs has been evaluated with cyclic voltammetry. Studies clearly suggest a structural reactivity correlation between radical scavenging and antioxidant properties of these isomers of HBA. Among the 3 isomers of HBAs, 4-HBA and 2-HBA are found to have better radical scavenging and antioxidant properties than 3-HBA.

Reactions of alpha-hydroxyalkyl radicals with 3,5-pyridinedicarboxylic acid (3,5-PDCA) and nicotinic acid (NA) were studied at appropriate pHs in aqueous solutions by pulse radiolysis technique. At pH 1, CH(3)C*HOH and *CH(2)OH radicals were found to react with 3,5-PDCA by rate constants of 2.2 x 10(9) and 5.1 x 10(8) dm(3) mol(-1) s(-1), respectively, giving radical adduct species. The adduct species formed in the reaction of CH(3)C*HOH radicals with 3,5-PDCA underwent unimolecular decay (k = 9.8 x 10(4) s(-1)) giving pyridinyl radicals. Reaction of (CH(3))(2)C*OH, CH(3)C*HOH, and *CH(2)OH radicals with NA at pH 3.3 gave the adduct species which subsequently decayed to the pyridinyl radicals. At pH 1, wherein NA is present in the protonated form, (CH(3))(2)C*OH radicals directly transfer electrons to NA, whereas CH(3)C*HOH and *CH(2)OH radicals react with higher rate constants compared with those at pH 3.3, initially giving the adduct species which subsequently undergo elimination reaction giving pyridinyl radicals. Reactions of alpha-hydroxyalkyl radicals with 3,5-pyridinedicarboxylic acid and nicotinic acid are found to proceed by an addition-elimination pathway that provides one of the few examples of organic inner sphere electron-transfer reactions. Rate constant for the addition reaction as well as rate of elimination varies with the reduction potential of alpha-hydroxyalkyl radicals.

A study of Clinico-epidemiological profile of fever cases admitted during epidemics of Chikungunya fever was carried out in Latur city of Maharashtra State. A total of 238 fever cases were investigated in relation to clinico-epidemilogical characteristics. Maximum fever cases admitted during epidemics of Chikungunya fever were in the age group 16-60 years (74.8%). There was no sex predominance. The commonest symptoms of admitted fever cases were sudden onset of high-grade fever (99.5%), followed by joint pains with tenderness on examination (90.7%), headache (58.4%) and body ache (23.5%). Average duration of illness was 3.01 days (S.D.=0.38). There was no mortality among affected fever cases. Family or neighborhood clustering of cases was observed in 66.8% and 31.5% of the cases respectively. The important environmental factors were presence of open water tank in the house (68%), infrequent cleaning and drying of non drinking water containers (once in 11 days) and abundance of mosquitoes in the house. (45.7%).

Aqueous extract of a natural herb, Terminalia chebula was tested for potential antioxidant activity by examining its ability to inhibit gamma-radiation-induced lipid peroxidation in rat liver microsomes and damage to superoxide dismutase enzyme in rat liver mitochondria. The antimutagenic activity of the extract has been examined by following the inhibition of gamma-radiation-induced strand breaks formation in plasmid pBR322 DNA. In order to understand the phytochemicals responsible for this, HPLC analysis of the extract was carried out, which showed the presence of compounds such as ascorbate, gallic acid and ellagic acid. This was also confirmed by cyclic voltammetry. The extract inhibits xanthine/xanthine oxidase activity and is also an excellent scavenger of DPPH radicals. The rate at which the extract and its constituents scavenge the DPPH radical was studied by using stopped-flow kinetic spectrometer. Based on all these results it is concluded that the aqueous extract of T. chebula acts as a potent antioxidant and since it is able to protect cellular organelles from the radiation-induced damage, it may be considered as a probable radioprotector.

Objective: To determine the relationship between birth weight and the anthropometric measurements of newborn to screen for low birth weight., Methods: 1,252 newborns have been enrolled in the study. The birth weight, mid-arm, head and chest circumferences were measured by standard techniques., Result: The highest correlation of birth weight was found with chest circumference (r = 0.70). The maximum sensitivity of detecting low birth weight was seen with chest circumference (94.26%)., Conclusion: Measurement of chest circumference being simple, easy, cheap and reliable method for identification of low birth weight in the community.

One and two electron oxidation reactions of peroxynitrite with trolox, an analogue of vitamin E were studied. Kinetics of the reaction was studied using a single mixing stopped-flow spectrometer in the pH range from 6 to 11 and the products were analyzed by HPLC/HPIC. One-electron oxidation reaction produced the phenoxyl radical of trolox having a characteristic absorption spectrum in the 300-500 nm region with absorption maximum at 430 nm. The rate constant for the formation of the trolox radical at 430 nm was determined to be 1.8 x 10(5) M(-1) s(-1). At low concentration of peroxynitrite the radical did not show any noticeable decay in the time scale of 20-50 s. However, when the concentration of peroxynitrite was increased, there was an appreciable increase in the decay of the trolox radical due to its reaction with excess peroxynitrite yielding a bimolecular rate constant of 6.0 x 10(3) M(-1) s(-1) for the reaction of trolox radical with peroxynitrite. The released nitrite and nitrate anions, and the two-electron oxidation product quinone produced as a result of these reactions, were estimated using ion chromatography and HPLC analysis. By following the changes in the yields of nitrite and quinone as a function of peroxynitrite concentration and from the above determined rate parameters, the relative importance of the one and two electron processes has been discussed.

A total of 635 mothers of under five children from urban slum area of Nanded city were assessed to know their awareness about home management of diarrhoea and symptoms of pneumonia. 48.5% of the mothers were unaware of any method of rehydrating the child with diarrhoea at home level followed by 36.2% mothers who were knowing home available fluids for rehydrating the child. 50.4% of the mothers were not knowing a single symptom of pneumonia followed by 35.1% mothers who were aware rapid abdominal movements (Pet Udna) as a symptom of pneumonia.