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The high thermal conductivity, high electron mobility, the direct wide band gap, and large exciton binding energy of zinc oxide (ZnO) make it appropriate for a wide range of device applications like light-emitting diodes, photodetectors, laser diodes, transparent thin-film transistors, and so forth. Among the semiconductor metal oxides, zinc oxide (ZnO) is one of the most commonly used gas-sensing materials. The gas sensor made of nanocomposite ZnO and Ga-doped ZnO (ZnO:Ga) thin films was developed by the sol-gel spin coating method. The gas sensitivity of gallium-doped ZnO thin films annealed at 400, 700, and 900 °C was studied for ethanol and acetone gases. The variation of electrical resistance of gallium-doped ZnO thin films with exposure of ethanol and acetone vapors at different concentrations was estimated. Ga:ZnO thin films annealed at 700 °C show the highest sensitivity and shortest response and recovery time for both ethanol and acetone gases. This study reveals that the 5 at. % Ga-doped ZnO thin film annealed at 700 °C has the best sensing property in comparison to the film annealed at 400 and 900 °C. The sensing response of ZnO:Ga thin films was found higher for ethanol gas in comparison to acetone gas.

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The limited thermoelectric performance of p-type Higher Manganese Silicides (HMS) in terms of their low figure-of-merit (ZT), which is far below unity, is the main bottle-neck for realising an efficient HMS based thermoelectric generator, which has been recognized as the most promising material for harnessing waste-heat in the mid-temperature range, owing to its thermal stability, earth-abundant and environmentally friendly nature of its constituent elements. We report a significant enhancement in the thermoelectric performance of nanostructured HMS synthesized using rapid solidification by optimizing the cooling rates during melt-spinning followed by spark plasma sintering of the resulting melt-spun ribbons. By employing this experimental strategy, an unprecedented ZT ∼ 0.82 at 800 K was realized in spark plasma sintered 5 at% Al-doped MnSi1.73 HMS, melt spun at an optimized high cooling rate of ∼2 × 107 K s-1. This enhancement in ZT represents a ∼25% increase over the best reported values thus far for HMS and primarily originates from a nano-crystalline microstructure consisting of a HMS matrix (20-40 nm) with excess Si (3-9 nm) uniformly distributed in it. This nanostructure, resulting from the high cooling rates employed during the melt-spinning of HMS, introduces a high density of nano-crystallite boundaries in a wide spectrum of nano-scale dimensions, which scatter the low-to-mid-wavelength heat-carrying phonons. This abundant phonon scattering results in a significantly reduced thermal conductivity of ∼1.5 W m-1 K-1 at 800 K, which primarily contributes to the enhancement in ZT.

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The report that gelonin cross-linked with monoclonal antibodies with the use of 2-iminothiolane (2-IT) exhibited higher cytotoxicity than the conjugates prepared with the use of N-succinimidyl-3-(2-pyridylthio) propionate (SPDP) alone, has prompted us to investigate the effect of epsilon-NH2 group modification with 2-IT on the ribosome-inactivating property (RIP) of gelonin. The purified gelonin was modified with 2-IT at a different molar ratio and their effects on immunoreactivity and ribosome-inactivating property were compared with those of N-succinimidyl 6-[3-(2-pyridyldithio) propionamido] hexanoate (long chain-SPDP) and SPDP modified gelonin derivatives. Modification of single amino group with 2-IT results in about 25-50% inhibition of immunoreactivity and 60-70% loss of protein synthesis inhibition activity. Modification of 2-3 amino groups further hampers both immunoreactivity and protein synthesis inhibition property of gelonin. Both the long chain-SPDP with SPDP modifications showed more pronounced effects on immunoreactivity and RIP activity as compared to the similar ratio of 2-IT modification(s). It may, therefore, be concluded that the positive charge plays an important role in the immunological as well as the protein synthesis inhibitory effect of gelonin.

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Ribosome inactivating proteins (RIPs) are a group of naturally occurring plant proteins with a RNA-N-glycosidases activity which depurinate rRNA at a specific universally conserved position (i.e. cleavage of N-glycosidic bond of a specific adenine of 28S rRNA). These proteins are found in different parts of plants, in concentrations ranging from a few micrograms to several hundred mg per 100 g of plant tissues. RIPs exist in two forms, type 1 having a single polypeptide chain with a molecular mass of approximately 30 kDa possessing N-glycosidase activity; and type 2 with two or four polypeptide chains having a molecular mass of approximately 60 kDa and approximately 120 kDa respectively showing lectin activity along with N-glycosidase moiety. Such biomolecules causing cytotoxicity are being exploited for designing immunotoxins/hormonotoxins using heterobifunctional conjugates. These carrier conjugates with the RIPs can influence cellular trafficking and inhibition of protein synthesis. We are witnessing a novel protein from plants that can be utilised for various therapeutical treatments ranging from cancers, AIDS and other viral diseases of present times.

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Gelonin, a ribosome-inactivating protein has been isolated from the seeds of Gelonium multifluorum of Euphorbiaceae family by two methods and the results are compared. In method-I conventional aqueous extraction, cation-exchange and gel-filtration chromatography has been used. In method-II S-Sepharose fast flow gel has been used to purify the proteins from the seed extract, followed by ammonium sulfate fractionation, cation-exchange and gel-filtration chromatography. Extensive physico-chemical and immunological characterizations show that molecular weight of gelonin as determined by gel-filtration chromatography and SDS-PAGE is approximately 30 kDa. The non-proteinous material which binds to CMC-gel in association with gelonin in method-I is substantially removed when gelonin is purified by method-II. Cation exchange, G-100 chromatography, RP-HPLC and SDS-PAGE show that method-II yields 50% more purified gelonin when compared to the yield by method-I. The immunoreactivity of gelonin obtained by methods I and II vary from 22-26% and 50-66% respectively and the ribosome-inactivating property vary from 46-56% and 70-87% respectively.

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The increasing use of heterobifunctional cross-linking agents in the design of defined conjugates for selective targeting and inducing immune response has prompted us to study the role of epsilon-NH2 group modification of oLH subunits, their recombination and effect on immunoreactivity, receptor binding and biological activity. The epsilon-NH2 groups of alpha oLH and beta oLH subunits were separately modified by using SMPT. The alpha oLH-SMPT modified derivatives hybridize to beta oLH. Similarly, the beta oLH-SMPT derivatives recombined with alpha oLH. The recombination was judged by gel filtration chromatography and RP-HPLC analysis. The sequential modification of subunits led to progressive reduction in immunoreactivity and receptor binding activity. The modification of six or more epsilon-NH2 groups in alpha oLH although recombine fully with native beta oLH but failed to react to anti-oLH antibody. Moreover, the steroidogenic activity was also abolished. Introduction upto four SMPT groups in alpha oLH compromised immunological and biological activities but further addition of two or more SMPT groups completely abolished antibody reactivity, receptor binding and steroidogenic activity indicating the importance of later two amino groups in the receptor binding and steroidogenic activity. The present investigation clearly demonstrate that only 1:2-3 molar ratio of oLH subunits:SMPT could generate the site(s) in the subunits of the oLH that retained reasonable immunological, receptor binding and biological activity of the hormone. Therefore, this molar ratio may be used in future for the design and synthesis of bioeffective hormonotoxins.

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In order to understand the significance of positive charge of lysine residues of ovine luteinizing hormone (oLH) on immunological and biological activity, the epsilon-NH2 group(s) of ovine LH were sequentially modified with 2-iminothiolane (2IT) that preserves the positive charge of the lysine while the overall charge of the hormone remains unchanged. These studies have also been compared with the oLH modified by N-succinimidyl 3-(2 pyridyldithio) propionate (SPDP) and succinimidyl 6-[3-(2-pyridyldithio)propionamido]hexanoate (LC-SPDP) that abolish positive charge of lysine residues. The modification primarily occurs in the alpha-subunit. Sequential modification led to progressive reduction in receptor binding and immunological activities. However, the steroidogenic activity was substantially retained. The immunoreactivity and receptor binding properties of 2IT modified oLH (oLH-2IT) were less affected when compared to SPDP (oLH-SPDP) or LC-SPDP (oLH-LC-SPDP) modified derivatives suggesting that increase in hydrophobic carbon chain in oLH-LC-SPDP molecule resulted in drastic inhibition in immunological and biological properties. But the steroidogenic potential of oLH-2IT, oLH-LC-SPDP or oLH-SPDP was relatively comparable. This suggests that a single -NH2 group modification with 2IT would generate the site in the hormone for conjugation to the toxin/carrier proteins that may retain better immunological and biological activity compared to that of SPDP or LC-SPDP modified oLH.

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Two hundred and eight patients of low back pain were studied in the department of orthopaedic surgery, GSVM Medical College, Kanpur. The patients were put on intensive conservative treatment in the form of analgesics, hard bed rest, spinal extension exercises, traction and lumbosacral support. Thirty-two patients did not respond to this treatment and their symptoms were of more than 6 months duration and they were subjected to epidural injection of local anaesthetic agent, saline and corticosteroids. The failed 6 cases were investigated for consideration of surgery. The aim of this study is to develop standardised strategy for the treatment of low back pain. For the low back pain patients not responding to intensive conservative treatment, an idea has been put forward in the form of epidural medication prior to considering them to surgery to prevent unnecessary incidence of "failed back". A trial of epidural injection is suggested to avoid surgery.

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The kinetic profiles of norfloxacin were evaluated in afebrile, febrile and probenecid pre-treated (70 mg/kg orally) febrile goats after a single intravenous (i.v.) dose (5 mg/kg). Fever was induced and maintained for 12 h by injecting Escherichia coli endotoxin (0.2 microgram/kg, i.v.) and repeating it in half the dose (0.1 microgram/kg) 5 h later. The plasma pharmacokinetic values for norfloxacin were best represented using a two-compartment open model. The peak norfloxacin plasma level of 90.52 +/- 3.18 micrograms/ml attained in the probenecid pre-treated febrile goats was higher than that in the febrile (75.46 +/- 0.72 micrograms/ml) or afebrile goats (62.25 +/- 1.23 micrograms/ml). ClB and Kel values were significantly (p < 0.01) decreased in febrile compared with afebrile goats. These values were further reduced in febrile goats after probenecid pre-treatment. However, t1/2 beta was not affected by the fever-probenecid interaction. Norfloxacin may be used as an infusion with probenecid in caprine diseases where very high plasma levels are required to combat resistant organisms such as Bacteroides.

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Lens, aqueous humour and serum LDH and its isoenzyme pattern were estimated in 50 patients with senile cataract; 10 each with immature senile cortical cataract, mature senile cortical cataract, hypermature senile cortical cataract, immature senile nuclear cataract and mature senile nuclear cataract. The gradual decrease in total LDH and activity in the lens with advancement of cataract was maximum in hypermature senile cortical cataract. Aqueous LDH and its isoenzyme pattern remained unaltered with the maturity of cataract, and serum LDH and its isoenzyme pattern were found to be within normal limits. The lens LDH activity was found to be not related to the serum and aqueous humour LDH activity, but LDH3 isoenzyme showed declining trend, whereas LDH5 isoenzyme increased with the maturity of cataract. The present study concluded that significant decrease in lens LDH did not bear any relationship to LDH in serum and aqueous humour in cases of senile cataract.

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Nyctanthes arbor tristis Linn. (Harsingar) is widely used as a decoction in the Ayurvedic system of medicine for treatment of sciatica and arthritis, but it has not yet been screened scientifically. In the present study, the water soluble portion of the alcoholic extract of the leaves of Nyctanthes arbor tristis (NAT) was screened for the presence of anti-inflammatory activity. NAT inhibited the acute inflammatory oedema produced by different phlogistic agents, viz. carrageenin, formalin, histamine, 5-hydroxytryptamine and hyaluronidase in the hindpaw of rats. The acute inflammatory swelling in the knee joint of rats induced by turpentine oil was also significantly reduced. In subacute models, NAT was found to check granulation tissue formation significantly in the granuloma pouch and cotton pellet test. Acute and chronic phases of formaldehyde induced arthritis were significantly inhibited. NAT was also found to inhibit the inflammation produced by immunological methods, viz. Freund's adjuvant arthritis and PPD induced tuberculin reaction. Thus anti-inflammatory activity in leaves of Harsingar supports its use in various inflammatory conditions by the followers of the Ayurvedic system of medicine.

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Interaction of insulin with beta-adrenoceptor antagonists was studied in conscious rabbits. Propranolol and metoprolol did not modify the peak of insulin hypoglycaemia but delayed its recovery. Practolol, sotalol and 1-INPEA enhanced the peak effect and delayed the recovery of insulin-induced hypoglycaemia. H 35/25 and d-INPEA did not modify insulin hypoglycaemia. The beta-blockers did not produce significant hypoglycaemia per se. Since sotalol, 1-INPEA (specific beta-adrenoceptor antagonists devoid of local anaesthetic activity); practolol and metoprolol (selective cardiac beta-1 adrenoceptor antagonists) enhanced hypoglycaemic action of insulin and H 35/25 (a selective beta-2 adrenoceptor antagonist) failed to affect it, it seems that selective beta-adrenoceptor blockade (similar to cardiac beta-1 adrenoceptors) mediates enhancement of insulin hypoglycaemia. Caution should, therefore, be exercised in administering beta-adrenoceptor antagonists and insulin together. A reduction in the dose of insulin may be necessary.

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