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11.
Uricase from bovine kidney, purified to homogeneity level, had a molecular weight of 70 kDa. The apparent K(m) and V(max) values for uric acid hydrolysis were 0.125 mM and 102 IU mg(-1) protein respectively. The activation energy requirement for uric acid hydrolysis by uricase and inactivation of enzyme were 11.6 and 14.5 kJ/M respectively. Both enthalpy (Delta H*) and entropy of activation (Delta S*) for uricase activity were lower than those reported for some thermostable enzymes.  相似文献   
12.
13.
Globally among biotic stresses, diseases like blight, rust and blast constitute prime constraints for reducing wheat productivity especially in Bangladesh. For sustainable productivity, the development of disease-resistant lines and high yielding varieties is vital and necessary. This study was conducted using 122 advanced breeding lines of wheat including 21 varieties developed by Bangladesh Wheat and Maize Research Institute (BAMRI) with aims to identify genotypes having high yield potential and resistance to leaf blight, leaf rust and blast diseases. These genotypes were evaluated for resistance against leaf blight and leaf rust at Dinajpur and wheat blast at Jashore under field condition. Out of 122 genotypes tested, 20 lines were selected as resistant to leaf blight based on the area under the diseases progress curve (AUDPC) under both irrigated timely sown (ITS) and irrigated late sown (ILS) conditions. Forty-two genotypes were found completely free from leaf rust infection, 59 genotypes were identified as resistant, and 13 genotypes were identified as moderately resistant to leaf rust. Eighteen genotypes were immune against wheat blast, 42 genotypes were categorized as resistant, and 26 genotypes were identified as moderately resistant to wheat blast. Molecular data revealed that the 16 genotypes showed a positive 2NS segment among the 18 immune genotypes selected against wheat blast under field conditions. The genotypes BAW 1322, BAW 1295, and BAW 1203 can be used as earlier maturing genotypes and the genotypes BAW 1372, BAW 1373, BAW 1297 and BAW 1364 can be used for lodging tolerant due to short plant height. The genotypes WMRI Gom 1, BAW 1349 and BAW 1350 can be selected for bold grain and the genotypes WMRI Gom 1, BAW 1297, BAW 1377 can be used as high yielder for optimum seeding condition but genotypes BAW 1377 and BAW 1366 can be used for late sown condition. The selected resistant genotypes against specific diseases can be used in the further breeding program to develop wheat varieties having higher disease resistance and yield potential.  相似文献   
14.
Pterygodermatites variabilis n. sp. (Nematoda: Rictulalarioidea) from the Indian gerbils Tatera indica collected from Sind and Baluchistan Provinces of Pakistan is described and compared with closely related species of the genus recovered from small mammalian hosts. The new species is characterised by a combination of the following characters: it possesses a regular crown of 26 and 14–38 denticles in male and female specimens respectively, 40–47 pairs of pre-vulvar spines, and a variable position of the vulva in specimens collected from different localities: it also differs in the size of the spicules and gubernaculum.  相似文献   
15.
Paeoninol and paeonin C, oligostilbene and monoterpene galactoside, have been isolated from the methanolic extract of the fruits of Paeonia emodi. Their structures have been assigned on the basis of spectral analysis including 1D and 2D NMR techniques. In addition, 4-hydroxybenzoic acid 3, gallic acid 4 and methyl gallate 5 have also been reported for the first time from this species. Compounds 1 and 2 have displayed potent inhibitory potential against enzyme lipoxygenase in a concentration-dependent fashion with the IC(50) values 0.77 and 99.5 microM, along with ABTS(.+) radical quenching activity with IC(50) values of 147.5 and 498.2 microM, respectively.  相似文献   
16.
Pheasant reintroduction and conservation efforts have been in place in Pakistan since the 1980 s, yet there is still a scarcity of data on pheasant microbiome and zoonosis. Instead of growing vast numbers of bacteria in the laboratory, to investigate the fecal microbiome, pheasants (green and ring neck pheasant) were analyzed using 16S rRNA metagenomics and using IonS5TMXL sequencing from two flocks more than 10 birds. Operational taxonomic unit (OTU) cluster analysis and phylogenetic tree analysis was performed using Mothur software against the SSUrRNA database of SILVA and the MUSCLE (Version 3.8.31) software. Results of the analysis showed that firmicutes were the most abundant phylum among the top ten phyla, in both pheasant species, followed by other phyla such as actinobacteria and proteobacteria in ring necked pheasant and bacteroidetes in green necked pheasant. Bacillus was the most relatively abundant genus in both pheasants followed by Oceanobacillus and Teribacillus for ring necked pheasant and Lactobacillus for green necked pheasant. Because of their well-known beneficial characteristics, these genus warrants special attention. Bird droppings comprise germs from the urinary system, gut, and reproductive sites, making it difficult to research each anatomical site at the same time. We conclude that metagenomic analysis and classification provides baseline information of the pheasant fecal microbiome that plays a role in disease and health.  相似文献   
17.
Pollen is a clinically important airborne allergen and one of the major causes of allergic conjunctivitis. A subpopulation of patients with atopic dermatitis (AD) are also known to have exacerbated skin eruptions on the face, especially around the eyelids, after contact with pollen. This pollen-induced skin reaction is now known as pollen dermatitis. Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine that plays an essential role in allergic inflammation. Recent findings suggest that MIF is involved in several allergic disorders, including AD. In this study, MIF knockout (KO), MIF transgenic (Tg) and WT littermate mice were immunized with ragweed (RW) pollen or Japanese cedar (JC) pollen and challenged via eye drops. We observed that the numbers of conjunctiva- and eyelid-infiltrating eosinophils were significantly increased in RW and JC pollen-sensitized MIF Tg compared with WT mice or MIF KO mice. The mRNA expression levels of eotaxin, interleukin (IL)-5 and IL-13 were increased in pollen-sensitized eyelid skin sites of MIF Tg mice. An in vitro analysis revealed that high eotaxin expression was induced in dermal fibroblasts by MIF combined with stimulation of IL-4 or IL-13. This eotaxin expression was inhibited by the treatment with CD74 siRNA in fibroblasts. These findings indicate that MIF can induce eosinophil accumulation in the conjunctiva and eyelid dermis exposed to pollen. Therefore, targeted inhibition of MIF might result as a new option to control pollen-induced allergic conjunctivitis and pollen dermatitis.  相似文献   
18.

Background

Recent studies suggest that acute sleep deprivation disrupts cellular immune responses by shifting T helper (Th) cell activity towards a Th2 cytokine profile. Since little is known about more long-term effects, we investigated how five days of sleep restriction would affect pro-inflammatory, chemotactic, Th1- and Th2 cytokine secretion.

Methods

Nine healthy males participated in an experimental sleep protocol with two baseline sleep-wake cycles (sleep 23.00 – 07.00 h) followed by 5 days with restricted sleep (03.00 – 07.00 h). On the second baseline day and on the fifth day with restricted sleep, samples were drawn every third hour for determination of cytokines/chemokines (tumor necrosis factor alpha (TNF-α), interleukin (IL) -1β, IL-2, IL-4 and monocyte chemoattractant protein-1 (MCP-1)) after in vitro stimulation of whole blood samples with the mitogen phytohemagglutinin (PHA). Also leukocyte numbers, mononuclear cells and cortisol were analysed.

Results

5-days of sleep restriction affected PHA-induced immune responses in several ways. There was a general decrease of IL-2 production (p<.05). A shift in Th1/Th2 cytokine balance was also evident, as determined by a decrease in IL2/IL4 ratio. No other main effects of restricted sleep were shown. Two significant interactions showed that restricted sleep resulted in increased TNF-α and MCP-1 in the late evening and early night hours (p’s<.05). In addition, all variables varied across the 24 h day.

Conclusions

5-days of sleep restriction is characterized by a shift towards Th2 activity (i.e. lower 1L-2/IL-4 ratio) which is similar to the effects of acute sleep deprivation and psychological stress. This may have implications for people suffering from conditions characterized by excessive Th2 activity like in allergic disease, such as asthma, for whom restricted sleep could have negative consequences.  相似文献   
19.
The present investigation dealt with the use of previously isolated and studied gamma-ray mutant strain Pseudomonas aeruginosa EBN-8 for the production of biosurfactant by using different hydrocarbon substrates viz. n-hexadecane, paraffin oil and kerosene oil, provided in minimal medium, as the sole carbon and energy sources. The batch experiments were conducted in 250 mL Erlenmeyer flasks, containing 50 mL minimal salt media supplemented with 1% (w/v) hydrocarbon substrate, inoculated by EBN-8 and incubated at 37 degrees C and 100 rpm in an orbital shaker. The sampling was done on 24 h basis for 10 d. The surface tension of cell-free culture broth decreased from 53 to 29 mN/m after 3 and 4 d of incubation when the carbon sources were paraffin oil and n-hexadecane, respectively. The largest reduction in interfacial tension from 26 to 0.4 mN/m was observed with n-hexadecane, while critical micelle dilution was obtained as 50 x CMC for paraffin oil as carbon source. When grown on n-hexadecane and paraffin oil, the EBN-8 mutant strain gave 4.1 and 6.3 g of the rhamnolipids/L, respectively. These surface-active substances subsequently allowed the hydrocarbon substrates to disperse readily as emulsion in aqueous phase.  相似文献   
20.
By baiting litter soils with raw potatoes, species of bacilli producing thermostable amylases and raw starch-degrading amylase were selectively isolated.  相似文献   
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