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1.
1. Activities of glucose 6-phosphate dehydrogenase (EC 1.1.1.49), 6-phosphogluconate dehydrogenase (EC 1.1.1.44), isocitrate dehydrogenase (EC 1.1.1.42), malate dehydrogenase (EC 1.1.1.37), malate dehydrogenase (decarboxylating) (EC 1.1.1.40), and pyruvate carboxylase (EC 6.4.1.1) were determined in subcellular fractions of mammary gland from rabbits during pregnancy, at different stages of lactation and during weaning. The results were compared with those obtained in similar experiments with rat mammary gland. 2. Three bases of expression of the activity of enzymes in the particle-free supernatant fraction of mammary gland were compared. During lactation, activity expressed per mg. of particle-free supernatant protein (uncorrected for milk protein) correlated well with that expressed per mug. of DNA phosphorus. The disadvantages of expressing activities per g. wet wt. are discussed. 3. The major differences between the two tissues were: (a) neither malate dehydrogenase (decarboxylating) nor a soluble form of pyruvate carboxylase could be detected in rabbit mammary gland at any stage of the lactation cycle; (b) isocitrate dehydrogenase increased in activity during lactation in rabbit mammary gland, but not in that of the rat. 4. Pyruvate carboxylase in the mitochondrial fraction of rabbit mammary gland, and in both the mitochondrial and the soluble fractions of rat mammary gland, did not change in activity during lactation. 5. For each tissue, the NADP-dependent dehydrogenases studied had a high activity at all stages of the lactation cycle compared with the rate of fatty acid synthesis at mid-lactation. The significance of these results is discussed with respect to the supply of NADPH via NADH.  相似文献   
2.
The body can host the spread of prostate cancer cells. Metastases from prostate cancer are more frequently seen in the brain, liver, lungs, and lymph nodes. A well-known antidiabetic drug, metformin, is also known to have antitumor effects. Our study focuses on the evaluation of potential metformin protective effects on brain and cerebellum damage in streptozotocin (STZ)-induced diabetic and Dunning prostate cancer models. In this investigation, six groups of male Copenhagen rats were created: control, diabetic (D), cancer (C), diabetic + cancer (DC), cancer + metformin, and diabetic + cancer + metformin. The brain and cerebellum tissues of the rats were taken after sacrifice. Oxidative stress markers including reduced glutathione level, lipid peroxidation, glutathione reductase, glutathione peroxidase, glutathione-S-transferase, catalase, superoxide dismutase activities, reactive oxygen species, total oxidant and total antioxidant status, lactate dehydrogenase, xanthine oxidase, acetylcholinesterase activities, protein carbonyl contents, nitric oxide and OH-proline levels, sodium potassium ATPase, carbonic anhydrase, and glucose-6-phosphate dehydrogenase activities; glycoprotein levels including hexose, hexosamine, fucose, and sialic acid levels; and histone deacetylase activity as a cancer marker were determined. Oxidative stress markers were impaired and glycoprotein levels and histone deacetylase activity were increased in the D, C, and DC groups. Metformin therapy reversed these effects. Metformin was found to protect the brain and cerebellum of STZ-induced diabetic rats with Dunning prostate cancer from harm caused by MAT-Lylu metastatic cells.  相似文献   
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Aluminum is an abundant metal in the earth’s crust that turns out to be toxic in acidic environments. Many plants are affected by the presence of aluminum at the whole plant level, at the organ level, and at the cellular level. Tobacco as a cash crop (Nicotiana tabacum L.) is a widely cultivated plant worldwide and is also a good model organism for research. Although there are many articles on Al-phytotoxicity in the literature, reviews on a single species that are economically and scientifically important are limited. In this article, we not only provide the biology associated with tobacco Al-toxicity, but also some essential information regarding the effects of this metal on other plant species (even animals). This review provides information on aluminum localization and uptake process by different staining techniques, as well as the effects of its toxicity at different compartment levels and the physiological consequences derived from them. In addition, molecular studies in recent years have reported specific responses to Al toxicity, such as overexpression of various protective proteins. Besides, this review discusses data on various organelle-based responses, cell death, and other mechanisms, data on tobacco plants and other kingdoms relevant to these studies.  相似文献   
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The present study is aimed at exploring different scanning parameters, detectors and their orientations for time-efficient and accurate commissioning of a 6 MV clinical linear accelerator (LINAC). Beam profiles and percentage depth dose (PDD) curves were measured with a PTW dosimetry diode, a PTW Semiflex and a PinPoint ion chamber in different orientations. To acquire beam data, equidistant (step size of 0.5 mm, 1 mm, 2 mm and 3 mm) and fanline (step size of 2–0.5 mm, 2–1 mm, 3–0.5 mm and 3-1 mm) scanning modes were employed and data measurement time was recorded. Scan time per measurement point was also varied (0.2 s, 0.5 s and 1.0 s) to investigate its effect on the accuracy and acquisition time of beam data. Accuracy of the measured data was analyzed on the basis of the variation between measured data and data modeled by a treatment planning system. Beam profiles (particularly in penumbra region) were found to be sensitive to variation in scanning resolution and showed an improved accuracy with decrease in step size, while PDD curves were affected negligibly. The accuracy of beam data obtained with the PTW dosimetry diode and the PinPoint ion chamber was higher than those obtained with the PTW Semiflex ion chamber for small fields (2?×?2 cm2 and 3?×?3 cm2). However, the response of the PTW diode and the PinPoint ion chamber was significantly indifferent in these fields. Furthermore, axial orientation of the PTW Semiflex ion chamber improved accuracy of profiles and PDDs as compared to radial orientation, while such a difference was not significant for the PinPoint ion chamber. It is concluded that a scan time of 0.2 s/point with a fanline scanning resolution of 2–1 mm for beam profiles and 3 mm for PDDs are most favorable in terms of accuracy and time efficiency. For small fields (2?×?2 cm2 and 3?×?3 cm2), a PinPoint ion chamber in radial orientation or a dosimetry diode in axial orientation are recommended for both beam profiles and PDDs. If a PinPoint ion chamber and a PTW dosimetry diode are not available, a Semiflex ion chamber in axial orientation may be used for small fields.

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7.
The 2-picolylamine is a simplest analogue of the alkaloid that has secondary and tertiary nitrogen function in its cyclic structure like that of alkaloids that can be derivatized to a number of biologically active compounds. In connection to our previous work, in the present work, three thiourea derivatives (I = 1,3-bis(2-benzyl-3-phenyl-1-(pyridine-2-yl) propyl) thiourea, II = 1,3-bis (pyridin-2-ylmethyl) thiourea, and III = 1-(2-benzyl-3-phenyl-1-(pyridine-2-yl) propyl)-3-phenylthiourea) were synthesized using 2-picolylamine template which is a readily available synthetic analogue of naturally occurring alkaloid. The biological effect of the synthesized derivatives were monitored on the activity of glucose-6-phosphatase in Swiss albino mice (21-days). The derivatives were also tested for their potential toxicity in a 28-days sub-chronic toxicity studies by assessing their effects on different parameters like hematological, serum biochemistry and liver histology. The therapeutic effect of the safe derivative (I) was examined in streptozotocin-induced diabetic mice as well. The derivatives showed inhibition of the enzyme activity from good to an excellent degree. Compound I had the highest inhibition with 21.42 ± 5.113 mg of the released phosphate as compared to that of the positive control group (84.55 ± 3.213 mg). Only I turned out to be safe for use in animals without exerting any toxic or lethal effects on any of the assessed parameters in the used animal model. Compound I efficiently reversed the effects like hyperglycemia, hyperlipidemia and weight loss in the test animals. Out of these three-tested compounds, I was found safe to be use as therapeutic agent in diabetes complications. However, further toxicological studies in other animal models are needed as well.  相似文献   
8.

Cotton fibre quality is a multigenic trait. Genetic modification of different genes to achieve high quality fibre is difficult without knowing the mechanism lying behind genes interaction. Based on background knowledge an attempt to explore the potential structural interactions between Gossypium hirsutum Wlim5 domain1 and Gossypium hirsutum ACTIN-1 proteins was done in current study. Sequence features of the LIM domain1 of GhWlim5 protein were identified through multiple sequence alignment analysis, and a phylogenetic tree was built to identify evolutionary relationships between sequences. Conservation indicated the evolutionary importance of side chain residues and the presence of several aliphatic and/or bulky residues, which stabilize the protein core and facilitate packing of zinc fingers. The structures of GhWlim5 domain1 and GhACTIN-1 proteins were modelled and validated through computational methods. Validation of GhACTIN-1 and GhWlim5 domain1 structures indicated good structural quality with 99.7% and 100% of the favoured number of residues in allowed regions and Z-score, within the ranges of − 9.87 and − 4.17, respectively. Docking analysis indicated various possible modes of interaction between these two proteins with favourable binding affinities. Based on our strong binding interaction results between GhWlim5 domain1 and GhACTIN-1 proteins, we further investigated the role of over-expression of GhWlim5 by transformation in cotton plants under fibre specific promoter and transgenic plants displayed significant increases in fibre strength.

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9.
Present study focuses on ameliorative potential of Typha elephantina leave’s aqueous (TE.AQ) extract against Paracetamol (PCM) induced toxicity in rabbits. We fed the male rabbits with 300 mg PCM in alone and in combination with TE.AQ at different doses i.e. (100, 200 and 300 mg/kg body weight) or silymarin (100 mg/kg) daily for 21 days. PCM in alone significantly (P < 0.5) increased serum urea, uric acid, creatinine, total protein, albumin, globulin and blood urea nitrogen. Serum sodium, potassium and magnesium level were high. The glutathione, radical scavenging activity and Thiobarbituric acid reactive substances were significantly reduced. Treatment with TE.AQ at dose rate 300 mg/kg body weight and Silymarin significantly ameliorated all the parameters when compared with PCM administered group. The 100 and 200 mg of TE.AQ showed no significant effects. The histopathological examination confirmed the therapeutic potential of TE.AQ. These results established the presence of natural antioxidants in Typha elephantina leaves.  相似文献   
10.
Root-knot nematodes Meloidogyne incognita (Kofoid and White) Chitwood and Rhizoctonia bataticola (Taub.) Butler, fungus, are very dangerous root damaging pathogens. Present study was planned to establish a chemical control of these root deteriorating pathogens under lab conditions as well as in field. Maximum death rate of nematode juveniles and minimum numbers of nematode eggs hatched were recorded in plates treated with Cadusafos (Rugby® 100G) @12 g/100 ml and Cartap® (4% G) @9g/100 ml. Chemical treatment of Rhizoctonia bataticola with Trifloxystrobin + Tebuconazole (Nativo®) @0.2 g/100 ml and Mancozeb + Matalaxyl (Axiom) @0.25 g/100 ml significantly controlled the mycelial growth in plates. The best treatments tested in laboratory were applied in field as protective and curative treatments. Results proved that chemical control of root-knot nematode and root rot fungi by tested chemicals at recommended time and dose is a significant management technique under field conditions.  相似文献   
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