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1.
Summary Optimised procedures for the production and recovery of lipase at 25 litre scale by submerged fermentation using aRhizopus species isolated from petroleum-soaked soil are developed. These lipase preparations are characterized by dual pH optima (4.0 and 8.0), wide temperature optima (over 80% activity between 40–57°C), broad specificity for substrates, high degree of tolerance for common salts and excellent stability during usage as well as storage. 相似文献
2.
G Singh M M Singh S C Maitra W Elger V Kalra S N Upadhyay S R Chowdhury V P Kamboj 《Journal of reproduction and fertility》1988,83(1):73-83
RU-38486 or ZK-98734 treatment (3 mg/day, s.c.) to intact or hysterectomized adult female rats on Days 5-7 post coitum induced changes characteristic of luteolysis. Ultrastructurally, the luteal cells exhibited an extensive vacuolization of the cytoplasm and perinuclear areas, degeneration of mitochondrial cristae, massive accumulation of lipid droplets, increase in number of lysosome like granules and heterochromatinization of the nucleus. In general, RU-38486 induced more marked degeneration of the luteal cells than did ZK-98734. There was also a significant decrease in peripheral plasma progesterone concentrations in treated rats. We suggest that these antiprogestagens act via inhibition of luteal function in addition to their antagonism at the uterine progesterone receptor level. 相似文献
3.
4.
Fred J. Genthner Janeshwar Upadhyay Robert P. Campbell Barbara R. Sharak Genthner 《Microbial ecology》1990,20(1):283-288
Culturable counts of antibiotic resistant, genetically engineeredPseudomonas fluorescens were determined on antibiotic-containing plate count agar during starvation in water. Prior to starvation, colony counts
obtained on all media separated into two groups. The mean of the colony counts on plate count agar with or without tetracycline
(4.9 × 106 ml−1) was significantly higher than the mean colony counts on plate count agar containing either nalidixic acid or nalidixic acid
plus tetraclycline (2.5×106 ml−1). After 20 days of starvation the highest mean colony counts continued to be obtained on plate count agar (7.2 × 106 ml−1) with slightly, but significantly, lower counts obtained on plate count agar containing either nalidixic acid (5.6 × 106 ml−1) or tetraclycline (1.5×106 ml−1). A combination of nalidixic acid and tetracycline in plate count agar, however, dramatically reduced colony counts (8.3
× 102 ml−1) after this starvation period. The addition of catalase to plate count agar containing nalidixic acid and tetracycline negated
the effect caused by this combination of antibiotics. When colony counts obtained over the entire 20 day incubation were considered,
the addition of MgSO4 to plate count agar containing nalidixic acid and tetracycline resulted in a significant increase in colony counts. Other
combinations of antibiotics, nalidixic acid+carbenicillin, nalidixic acid+kanamycin, streptomycin+tetracycline, streptomycin+carbenicillin,
rifampicin+tetracycline, rifampicin+carbenicillin, and rifampicin+kanamycin, did not inhibit colony formation of starved cells.
Antibiotic resistant strains ofP. putida andEscherichia coli also displayed sensitivity to the combination of nalidixic acid and tetracycline in plate count agar after starvation. 相似文献
5.
Narasimha Pullaguri Ashwini Umale Anamika Bhargava 《Journal of biochemical and molecular toxicology》2023,37(2):e23244
Several scientific studies have suggested a link between increased exposure to pollutants and a rise in the number of neurodegenerative disorders of unknown origin. Notably, triclosan (an antimicrobial agent) is used in concentrations ranging from 0.3% to 1% in various consumer products. Recent studies have also highlighted triclosan as an emerging toxic pollutant due to its increasing global use. However, a definitive link is missing to associate the rising use of triclosan and the growing number of neurodegenerative disorders or neurotoxicity. In this article, we present systematic scientific evidence which are otherwise scattered to suggest that triclosan can indeed induce neurotoxic effects, especially in vertebrate organisms including humans. Mechanistically, triclosan affected important developmental and differentiation genes, structural genes, genes for signaling receptors and genes for neurotransmitter controlling enzymes. Triclosan-induced oxidative stress impacting cellular proteins and homeostasis which triggers apoptosis. Though the scientific evidence collated in this article unequivocally indicates that triclosan can cause neurotoxicity, further epidemiological studies may be needed to confirm the effects on humans. 相似文献
6.
A K Jaiswal S N Upadhyay S K Bhattacharya 《Indian journal of experimental biology》1991,29(6):532-537
The study was conducted on 64 Charles Foster strain albino rats, which were equally distributed into 8 evenly matched groups, following a 2 x 2 x 2 factorial design, by varying three independent factors at two levels: nutrition--normal and undernutrition; environment--enrichment and impoverishment, and drug treatment--vehicle and dihydroergotoxine (3 mg/kg, i.p.). Prenatal undernutrition was induced by restricting the mother's food intake. The environmental enrichment/impoverishment and the vehicle/dihydroergotoxine treatments were given during the postweaning period of the pups. The rats were subjected to original and subsequent reversal brightness discrimination learning tests in a single unit T-maze at 8-9 weeks of age. Thereafter, the animals were tested for passive avoidance learning. The results indicate that undernutrition caused significant original and reversal discrimination learning, deficits whereas environmental deprivation attenuated only the original discrimination learning performance. Dihydroergotoxine treatment facilitated the learning performance of rats in both the original and reversal learning tests. Nutritional, environmental and dihydroergotoxine treatments had no effect on the retention of the passive avoidance learning, both at 24 hr and 1 week intervals. Dihydroergotoxine treatment attenuated the learning deficits induced by prenatal undernutrition. The results indicate that dihydroergotoxine is not likely to be useful in cognitive deficits, induced by malnutrition, though it facilitated learning acquisition, since it had no effect on retention. 相似文献
7.
Food preference as well as feeding efficiency studies of the carabid predator revealed that the grub of theChlaenius bioculatus
Chaud preferred mostPolytella gloriosae F. larvae in both 2nd and 3rd instar.Tarache tropica
Guénée was preferred least by the grub predator in both instar.T. tropica was found toxic and grubs of the predator died after consumption.
Résumé Les préférences alimentaires, de même que l'efficacité prédatrice deChlaenius bioculatus Chaud, montrent que ce carabide prédateur préfère le plus les larves dePolytella gloriosae F. du 2e et 3e stade.Tarache tropica Guénée est le moins attaqué aux deux stades.T. tropica est toxique et les larves du prédateur meurent après sa consommation.相似文献
8.
Syed Husne Mobarak Anamika Koner Saubhik Mitra Paroma Mitra Anandamay Barik 《Journal of Applied Entomology》2020,144(7):616-631
Green gram, Vigna radiata (L.) Wilczek, is an important pulse crop of Asia. Severe attack by the larvae of Spilosoma obliqua Walker (Lepidoptera: Arctiidae) causes defoliation of green gram and reduces seed yield. Females lay eggs on the leaf surface, and therefore, surface wax plays an important role as short-range attractant and oviposition stimulant. So, we have attempted to find out whether leaf surface wax compounds (alkanes and free fatty acids) from three green gram cultivars (PDM 54, PUSA BAISAKHI and SAMRAT) could act as short-range attractant and oviposition stimulant in females. The TLC, GC-MS and GC-FID analyses of n-hexane extracts revealed 20 n-alkanes from n-C15 to n-C36 and 13 free fatty acids from C12:0 to C21:0, whilst linoleic acid was unique in SAMRAT. Pentacosane was the predominant amongst n-alkanes in the leaf surface waxes of three cultivars. Heneicosanoic acid and palmitoleic acid were the predominant free fatty acids in the leaf surface waxes of PDM 54, and PUSA BAISAKHI and SAMRAT, respectively. Females were attracted towards one leaf equivalent surface wax of three green gram cultivars against solvent controls (n-hexane) in Y-tube olfactometer bioassays. A synthetic blend of pentacosane, heptacosane, nonacosane, hexatriacontane, palmitoleic acid, linolenic acid and stearic acid, a synthetic blend of pentacosane, hexatriacontane and stearic acid, and a synthetic blend of hexatriacontane, linolenic acid and stearic acid resembling in amounts present in one leaf equivalent surface wax of PDM 54, PUSA BAISAKHI and SAMRAT, respectively, served as short-range attractant and oviposition stimulant in females. Females showed equal preference for egg laying towards the above three synthetic blends when these blends were tested against each other, and hence, these blends could be employed in development of baited traps in pest management strategies. 相似文献
9.
Upadhyay Udita Zhuang Gerald Z. Diatchenko Luda Parisien Marc Kang Yuan Sarantopoulos Konstantinos D. Martin Eden R. Smith Shad B. Maixner William Levitt Roy C. 《Mammalian genome》2020,31(9-12):287-294
Mammalian Genome - Intracellular calcium is critical in orchestrating neuronal excitability and analgesia. Carbonic anhydrase-8 (CA8) regulates intracellular calcium signaling through allosteric... 相似文献
10.
Sahoo Kamalakanta Upadhyay Amit Runge Troy Bergman Richard Puettmann Maureen Bilek Edward 《The International Journal of Life Cycle Assessment》2021,26(1):189-213
The International Journal of Life Cycle Assessment - Producing biochar from forest residues can help resolve environmental issues by reducing forest fires and mitigating climate change. However,... 相似文献