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91.
The aim of this study was to investigate the possible effects of the seasonal and physiological variations on the Cu, Zn, Mg, Fe, Se, Ca, K, Na, Cl, and P concentrations and their relationships with the estradiol and progesterone levels in Sakiz-Ivesi sheep. For this purpose 34 healthy Sakiz-Ivesi crossbreed sheep were divided into two groups. The first group (n=22) was mated and the second group (n=12) was not mated. They were raised under pasture conditions and without any dietary supplementation. Their serum samples were collected four times a year at each season and under each physiologic condition. The periods are 1=early pregnancy (October), 2=late pregnancy (January), 3=lactation (April), and 4=dry season (July). The results of this study indicated that (1) Mg concentrations in serum vary with seasonal variations but not physiological variations, (2) Fe and K concentrations in serum vary only with physiological variations, (3) the Cu concentration changes not only pregnancy but also through some other hormonal changes not caused by pregnancy, (4) Ca, P, and Se concentrations could vary with both physiologic and seasonal variations, (5) Zn, Na, and Cl were almost identical for both groups and altered depending on neither season of the year nor the physiologic status, (6) both increased estradiol level and increased progesterone level can raise Cu levels in serum, and (7) increased serum Ca concentrations are related with increased estradiol and decreased P and Mg levels. These observations suggest that seasonal and physiologic variations and sexual cycle have to be taken into consideration for a correct ***DIRECT SUPPORT *** A02Q2015 00006 interpretation of elements status. If sheep are maintained at pasture conditions, the nutritional requirements must be supplemented during certain periods. Otherwise, it is apparent that this will cause a decline in the total performance of sheep and, consequently, economic lost.  相似文献   
92.
Prolactinoma is the most common pituitary tumor. Most pituitary tumors are benign, but they often are clinically signi?cant. We investigated cytokinesis-block micronucleus cytome (CBMN cyt) assay parameters and oxidative DNA damage in patients with prolactinoma to assess the relations among age, prolactin level, pituitary adenoma diameter and 8-hydroxy-2’-deoxyguanosine (8-OHdG) level in patients with prolactinoma. We investigated 27 patients diagnosed with prolactinoma and 20 age- and sex-matched healthy controls. We measured CBMN cyt parameters and plasma 8-OHdG levels in peripheral blood lymphocytes of patients with prolactinoma and controls. The frequencies of micronucleus (MN), nucleoplasmic bridge, nuclear bud, apoptotic and necrotic cells, and plasma 8-OHdG levels in patients with prolactinoma were significantly greater than controls. MN frequency was correlated positively with age, prolactin levels and pituitary adenoma diameters in patients with prolactinoma. The increased chromosomal and oxidative DNA damage, and the positive correlation between MN frequency, prolactin levels and pituitary adenoma diameters may be associated with increased risk of cancer in patients with prolactinoma, because increased MN frequency is a predictor of cancer risk.  相似文献   
93.
A systems approach to biology requires a principled approach to pathway identification. In this study, the two nuclear petite yeast mutants K1Deltapet191a and K1Deltapet191ab and their parental industrial strain K1 were cultured in glucose-containing microaerobic chemostats. Exometabolomic profiles were used to infer the differences in the fermentation characteristics and respiration capacity of the strains. The ability of the metabolite measurement information to describe genetically different strains was investigated using a genome-scale yeast model. Flux balance analysis (FBA) of the model reveals that the objective function of minimal oxygen consumption enables the identification of the effect of genotypic differences when combined with the knowledge of the extracellular state of metabolism. The predicted decrease in oxygen consumption flux of K1Deltapet191a and K1Deltapet191ab strains with respect to the parental strain is about 80% and 100%, respectively, which coincides with the respiratory deficiencies of the strains. The expected increase in ethanol production rates in response to the decrease in the respiratory capacity was also predicted to be very close to the experimental values. This study shows the predictive power of the integrated analysis of genome-scale models with exometabolomic profiles, since accurate predictions could be made without any information about the respiration capacity of the strains. The FBA approach thereby enables identification of responsive pathways and so permits the elucidation of the genetic characteristics of strains in terms of expressed metabolite profiles.  相似文献   
94.
The hydrodistillated essential oil of Salvia hydrangea was analyzed by GC–MS. Fifty-four different components representing 95.9% of the compounds in the oil were identified. Camphor (54.2%), -humulene (4.0%), cis-sesquisabinene hydrate (2.8%), myrtenol (2.6%), β-bisabolol (2.2%) and 1,8-cineole (2.1%) were found to be predominant components. The oil was also characterized by relatively high amount of oxygenated monoterpenes (69.6%). The oil was tested for fungitoxic effects against 33 agricultural pathogenic fungi using in vitro microbial growth inhibition assays. The oil exhibited considerable antifungal activity against a broad spectrum of tested fungi. Antibacterial activity of the oil was determined against 30 bacterial strains using the disc diffusion method. The oil had a very wide spectrum of antibacterial activity. However, it was not as active as penicillin. The oil showed 68.3–75.0% mortality against adults of Sitophilus granarius and Tribolium confusum, the major pests of wheat and wheat products, respectively. It can be concluded that the oil of S. hydrangea has a potential against agricultural pathogenic fungi and two stored pests, S. granarius and T. confusum.  相似文献   
95.
Previous studies showed that efforts to further elevate starch synthesis in rice (Oryza sativa) seeds overproducing ADP-glucose (ADPglc) were prevented by processes downstream of ADPglc synthesis. Here, we identified the major ADPglc transporter by studying the shrunken3 locus of the EM1093 rice line, which harbors a mutation in the BRITTLE1 (BT1) adenylate transporter (OsBt1) gene. Despite containing elevated ADPglc levels (approximately 10-fold) compared with the wild-type, EM1093 grains are small and shriveled due to the reduction in the amounts and size of starch granules. Increases in ADPglc levels in EM1093 were due to their poor uptake of ADP-[14C]glc by amyloplasts. To assess the potential role of BT1 as a rate-determining step in starch biosynthesis, the maize ZmBt1 gene was overexpressed in the wild-type and the GlgC (CS8) transgenic line expressing a bacterial glgC-TM gene. ADPglc transport assays indicated that transgenic lines expressing ZmBT1 alone or combined with GlgC exhibited higher rates of transport (approximately 2-fold), with the GlgC (CS8) and GlgC/ZmBT1 (CS8/AT5) lines showing elevated ADPglc levels in amyloplasts. These increases, however, did not lead to further enhancement in seed weights even when these plant lines were grown under elevated CO2. Overall, our results indicate that rice lines with enhanced ADPglc synthesis and import into amyloplasts reveal additional barriers within the stroma that restrict maximum carbon flow into starch.Cereal grains contribute a significant portion of worldwide starch production. Unlike other plant tissue, starch biosynthesis in the endosperm storage organ of cereal grains is unique in its dependence on two ADP-Glc pyrophosphorylase (AGPase) isoforms (Denyer et al., 1996; Thorbjørnsen et al., 1996; Sikka et al., 2001), a major cytosolic enzyme and a minor plastidial one, to generate ADP-glucose (ADPglc), the sugar nucleotide utilized by starch synthases in the amyloplast (Cakir et al., 2015). The majority of ADPglc in cereal endosperm is generated in the cytosol from AGPase (Tuncel and Okita, 2013) as well as by Suc synthase (Tuncel and Okita, 2013; Bahaji et al., 2014) and subsequently transported into amyloplasts by the BRITTLE-1 (BT1) protein located at the plastid envelope (Cao et al., 1995; Shannon et al., 1998).The Bt1 gene, first identified in maize (Zea mays; Mangelsdorf, 1926) and isolated by Sullivan et al. (1991), encodes a major amyloplast membrane protein ranging from 39 to 44 kD (Cao et al., 1995). The BT1 protein and its homologs belong to the mitochondrial carrier family (Sullivan et al., 1991; Haferkamp, 2007), which has a diverse range of substrates (Patron et al., 2004; Leroch et al., 2005; Kirchberger et al., 2008). The assignment of BT1 protein as the ADPglc transporter in cereal endosperms was first proposed by Sullivan et al. (1991), and then it was characterized based on the increased ADPglc levels and reduced ADPglc import rate in endosperms of BT1-deficient maize and barley (Hordeum vulgare) mutants (Tobias et al., 1992; Shannon et al., 1996, 1998; Patron et al., 2004). Biochemical transport studies of the maize BT1 showed that it imported ADPglc by counter exchanging with ADP (Kirchberger et al., 2007). The wheat (Triticum aestivum) BT1 homolog also transports ADPglc but has similar affinities for ADP and AMP as the counter-exchange substrate (Bowsher et al., 2007).Evidence from previous studies by our laboratory (Sakulsingharoj et al., 2004; Nagai et al., 2009) suggested the potential role of BT1 as well as other downstream processes as a rate-limiting step in starch biosynthesis in the transgenic rice (Oryza sativa) GlgC (CS8) lines overexpressing an up-regulated AGPase (Escherichia coli glgC-TM). In GlgC (CS8) rice lines, grain weights (starch) are elevated up to 15% compared with wild-type plants, indicating that the AGPase-catalyzed reaction is a rate-limiting step in starch biosynthesis under normal conditions. When transgenic GlgC (CS8) plants were grown under elevated CO2 levels, no further increases in grain weight were evident compared with those grown at ambient CO2. As Suc levels are elevated in leaf blades, leaf sheaths, culms (Rowland-Bamford et al., 1990), and peduncle exudates (Chen et al., 1994) in rice plants grown under elevated CO2, developing GlgC (CS8) grains were unable to convert the increased levels of sugars into starch. This lack of increase indicated that the AGPase-catalyzed reaction (ADPglc synthesis) was no longer rate limiting and that one or more downstream processes regulated carbon flux from source tissues in developing GlgC (CS8) endosperm (Sakulsingharoj et al., 2004). This view is also supported by a subsequent metabolite study in which several GlgC (CS8) lines were found to contain up to 46% higher ADPglc levels than wild-type plants (Nagai et al., 2009). As this increase in ADPglc levels was nearly 3-fold higher than the increase in grain weight, starch biosynthesis is saturated with respect to ADPglc levels and carbon flow into starch is restricted by one or more downstream steps. Potential events that may limit the utilization of ADPglc in starch in GlgC (CS8) lines are the import of this sugar nucleotide via the BT1 transporter into amyloplasts and/or the utilization of ADPglc by starch synthases. Mutant analysis of the two major starch synthases indicated no significant impact on grain weight when one of these starch synthases was nonfunctional, suggesting that this enzyme activity, contributed by multiple enzyme isoforms, is present at excessive levels (Fujita et al., 2006, 2007). Therefore, we suspected that BT1 is the likely candidate limiting carbon flow into starch in GlgC (CS8) endosperms.The aim of this study was to investigate the role of BT1 in mediating the transport of ADPglc into amyloplast and to determine whether this transport activity is rate limiting in rice endosperm. In order to address these questions, we show that BT1 is the major transporter of ADPglc by analysis of the EM1093 rice line, which contains a mutation at the shrunken3 (shr3) locus and, specifically, in the OsBt1-1 gene. Second, we assessed the impact of the expression of the maize ZmBt1 gene in wild-type and GlgC (CS8) seeds to determine the potential limiting role of BT1 transport activity on starch biosynthesis. Our results indicate that BT1 is essential for starch synthesis but is not rate limiting and that one or more stroma-localized processes limit maximum carbon flow into starch.  相似文献   
96.
97.
In the common housefly, the presence or absence of a male-determining factor, M, is responsible for sex determination. In different strains, M has been found on the Y, on the X, or on any of the five autosomes. By analyzing a Y-autosomal translocation and a ring-shaped, truncated Y chromosome, we could show that M on the Y consists of at least two regions with M activity: One of them can be assigned to the short arm of the Y chromosome (MYS), which is largely C-banding negative, the other region lies on the C-banding positive long arm of the Y, including the centromeric part (MYL). Each region alone behaves as a hypomorphic M factor, causing many carriers to develop as intersexes of the mosaic type instead of as males. When introduced into the female germ line by transplantation of progenitor germ cells (pole cells), the MYS shows an almost complete maternal effect that predetermines 96% of the genotypic female (NoM) animals to develop as males. In contrast, the MYL has largely lost its maternal effect, and most of the NoM animals develop as females. Increasing the amount of product made by either of the two hypomorphic M factors (by combining the MYS and MYL or two MYS) leads to complete male development in almost every case. We thus assume that the Y chromosome carries at least two copies of M, and that these are functionally equivalent.  相似文献   
98.
99.
A new series of 6, 7-dihydroxy-3-(methylphenyl) chromenones, including three new derivatives, i.e. 6,7-dihydroxy-3-(2-methylphenyl)-2H-chromen-2-one (OPC); 6,7-dihydroxy-3-(3-methylphenyl)-2H-chromen-2-one (MPC); 6,7-dihydroxy-3-(4-methylphenyl)-2H-chromen-2-one (PPC) and one previously described, namely 6,7-dihydroxy-3-phenyl-2H-chromen-2-one (DPC), were synthesized. These compounds were investigated as inhibitors of human carbonic anhydrase I (hCA-I) and human carbonic anhydrase II (hCA-II) which had been purified from human erythrocytes on an affinity gel comprised of L-tyrosine-sulfonamide-Sepharose 4B.  相似文献   
100.
In this study, methanol, ethanol, methanol-dichloromethane (1 : 1, v/v), acetone, ethyl acetate, diethyl ether, and chloroform extracts of lavender (Lavandula stoechas L. subsp. stoechas) were prepared by maceration, and the ursolic acid contents in the extracts were determined quantitatively by HPLC analyses. The present results show that the methanol-dichloromethane (1 : 1, v/v) solvent system is the most efficient solvent system for the extraction of ursolic acid from the plant sample with the highest yield (2.22 g/100 g plant sample). In the present study, a new practical method for the isolation of ursolic acid from polar extracts was also demonstrated for the first time. The inhibition effects of the extracts and ursolic acid were also revealed on α-glycosidase, acetylcholinesterase, butyrylcholinesterase, and human carbonic anhydrase I and II enzymes by determining IC50 values for the first time. The extracts and ursolic acid acted as potent antidiabetic agents by strongly inhibiting the α-glycosidase activity, whereas they were found to be very weak neuroprotective agents. In view of the present results, L. stoechas and its major metabolite, ursolic acid, can be recommended as a herbal source to control postprandial blood sugar levels and prevent diabetes by delaying the digestion of starch in food.  相似文献   
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