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11.
It is accepted that angiogenesis plays an important role in the development of the corpus luteum (CL) and is probably necessary for normal lutein cell function. A number of drugs currently being tested in clinical trials as possible angiogenesis inhibitors were not originally developed with the intention of suppressing tumor angiogenesis. Interferon alpha (IFN-alpha) is one of the notable examples of such 'accidental angiogenesis inhibitors' and daily administration of IFN-alpha is known to suppress tumor growth, tumor vascularization, and down-regulation of various growth factors. We investigated the effects of IFN-alpha treatment on the expression of vascular endothelial growth factor (VEGF), and its receptors KDR and Flt-1, and CD34 in CL during the first week of pseudopregnancy and pregnancy in hormonally induced rat ovaries by immunohistochemistry and Western blot techniques. Basal body temperatures of the drug-treated rats, as an indicator of treatment effect, were determined daily and were increased significantly when compared to controls (38.03 +/- 0.18 vs. 36.6 +/- 0.1 degrees C), respectively. The effect of IFN-alpha treatment was minimal when the entire week was evaluated, however, the expression of VEGF decreased at 3rd, 5th, and 7th days of both pregnancy and pseudopregnancy, when compared to the 1st day, whereas there was not a such alteration in the untreated rats regarding these days. The daily subcutaneous administrations of 672.500 U IFN-alpha2b had minimal effects on the expressions of VEGF, and its two receptors KDR and Flt-1 in either pregnant or pseudopregnant corpora lutea utilizing HSCORE.  相似文献   
12.
The gene for juvenile hyaline fibromatosis maps to chromosome 4q21   总被引:3,自引:0,他引:3       下载免费PDF全文
Juvenile hyaline fibromatosis (JHF) is an autosomal recessive condition characterized by multiple subcutaneous nodular tumors, gingival fibromatosis, flexion contractures of the joints, and an accumulation of hyaline in the dermis. We performed a genomewide linkage search in two families with JHF from the same region of the Indian state of Gujarat and identified a region of homozygosity on chromosome 4q21. Dense microsatellite analyses within this interval in five families with JHF who were from diverse origins demonstrate that all are compatible with linkage to chromosome 4q21 (multipoint LOD score 5.5). Meiotic recombinants place the gene for JHF within a 7-cM interval bounded by D4S2393 and D4S395.  相似文献   
13.
The water-distilled essential oil the leaves of Coridothymus capitatus were analyzed by GC/MS and also analyzed by direct thermal desorption GC/MS. Comparison was made between two analyses techniques. The essential oil consisted mainly of monoterpenes 98.9%, while oxygenated hydrocarbons were identified as 55.6 % and non-oxygenated hydrocarbons as 43.6%. As major components were found carvacrol (35.6%), p-cymene (21.0%), thymol (18.6%), gamma-terpinene (12.3%), alpha-terpinene (3.2%), beta-myrcene (3.0%) and alpha-thujene (1.3%) by hydrodistillation and by the GC/MS method. The direct thermal desorption GC/MS analysis also showed the same major components, namely carvacrol (51.6%), thymol (21.7%), p-cymene (9.7%) gamma-terpinene (8.2%), alpha-terpinene (1.64%). The essential oil of C. capitatus showed strong activity against S. aureus, P. vulgaris, P. aeruginosa, E. coli, K. pneumonia, B.  相似文献   
14.
A DNA aptamer specific for Thermus aquaticus DNA polymerase (Taq-polymerase) was immobilized on magnetic beads, which were prepared in the presented study. The effect of various parameters including pH, temperaturem and aptamer concentration on the immobilization of 5'-thiol labeled DNA-aptamer onto glutaric dialdhyde activated magnetic beads was evaluated. The binding conditions of Taq-polymerase on the aptamer immobilized magnetic beads were studied using commercial Taq-polymerase to characterize the surface complexation reaction. Efficiency of affinity magnetic beads in the purification of recombinant Taq-polymerase from crude extracts was also evaluated. For this case, the enzyme "recombinant Taq-DNA polymerase" was cloned and expressed using an Amersham E. coli GST-Gene Fusion Expression system. Crude extracts were in contact with affinity magnetic beads for 30 min and were collected by magnetic field application. The purity of the eluted Tag-polymerase from the affinity beads, as determined by HPLC, was 93% with a recovery of 89% in a one-step purification protocol. Apparently, the system was found highly effective as one step for the low-cost purification of Taq-polymerase in bacterial crude extract.  相似文献   
15.
Traumatic injury to the brain or spinal cord and multiple sclerosis (MS) share a common pathophysiology with regard to axonal demyelination. Despite advances in central nervous system (CNS) repair in experimental animal models, adequate functional recovery has yet to be achieved in patients in response to any of the current strategies. Functional recovery is dependent, in large part, upon remyelination of spared or regenerating axons. The mammalian CNS maintains an endogenous reservoir of glial precursor cells (GPCs), capable of generating new oligodendrocytes and astrocytes. These GPCs are upregulated following traumatic or demyelinating lesions, followed by their differentiation into oligodendrocytes. However, this innate response does not adequately promote remyelination. As a result, researchers have been focusing their efforts on harvesting, culturing, characterizing, and transplanting GPCs into injured regions of the adult mammalian CNS in a variety of animal models of CNS trauma or demyelinating disease. The technical and logistic considerations for transplanting GPCs are extensive and crucial for optimizing and maintaining cell survival before and after transplantation, promoting myelination, and tracking the fate of transplanted cells. This is especially true in trials of GPC transplantation in combination with other strategies such as neutralization of inhibitors to axonal regeneration or remyelination. Overall, such studies improve our understanding and approach to developing clinically relevant therapies for axonal remyelination following traumatic brain injury (TBI) or spinal cord injury (SCI) and demyelinating diseases such as MS.  相似文献   
16.
There is little information about the hepatoprotective effects of gallic acid against ischemia–reperfusion (I/R) damage. Animals were subjected to I/R. Gallic acid at doses of 50 and 100 mg/kg body weight (bw) were injected as a single dose prior to ischemia. Liver tissue homogenates were used for the measurement of malondialdehyde (MDA), catalase (CAT) and glutathione peroxidase (GPx) levels. At the same time alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were assayed in serum samples and compared statistically. While the ALT, AST, LDH activities and MDA levels were significantly increased, CAT and GPx activities significantly decreased in only I/R-induced control rats compared to normal control rats (P < 0.05). Treatment with gallic acid at a dose of 100 mg/kg bw significantly decreased the ALT, AST, LDH activities and MDA levels, and markedly increased activities of CAT and GPx in tissue homogenates compared to I/R-induced rats with no treatment group (P < 0.05). In oxidative stress generated by hepatic ischemia–reperfusion, gallic acid contributes partially an alteration in the delicate balance between the scavenging capacity of antioxidant defense systems and free radicals in favour of the antioxidant defense systems in the body.  相似文献   
17.
Poly(2-hydroxyethyl methacrylate/ethylenglycol dimethacrylate) beads were grafted with poly(glycidylmethacrylate) via surface initiated atom transfer radical polymerization. Epoxy groups of the grafted polymer were modified in to sulfone groups. Sulfonated beads were characterized by swelling studies, FT-IR, SEM and elemental analysis, and were used for reversible immobilization of lipase. Under given experimental conditions, the beads had an adsorption capacity of 44.7 mg protein/g beads. The adsorbed lipase on beads retained up to 67.4% of its initial activity. The immobilized lipase exhibited improved thermal and storage stabilities over those of the free enzyme. The immobilized lipase could desorb 1.0 M NaCl solution at pH 8.0, and the sulfonated beads can be repeatedly charged with fresh enzyme after inactivation upon use.  相似文献   
18.
Grilley D  Misra V  Caliskan G  Draper DE 《Biochemistry》2007,46(36):10266-10278
RNA molecules in monovalent salt solutions generally adopt a set of partially folded conformations containing only secondary structure, the intermediate or I state. Addition of Mg2+ strongly stabilizes the native tertiary structure (N state) relative to the I state. In this paper, a combination of experimental and computational approaches is used to estimate the free energy of the interaction of Mg2+ with partially folded I state RNAs and to consider the possibility that Mg2+ favors "compaction" of the I state to a set of conformations with a higher average charge density. A sequence variant with a drastically destabilized tertiary structure was used as a mimic of I state RNA; as measured by small-angle X-ray scattering, it adopted a progressively more compact conformation over a wide Mg2+ concentration range. Average free energies of the interaction of Mg2+ with the I state mimic were obtained by a fluorescence titration method. To interpret these experimental data further, we generated molecular models of the I state and used them in calculations with the nonlinear Poisson-Boltzmann equation to estimate the change in Mg2+-RNA interaction free energy as the average I state dimensions decrease from expanded to compact. The same models were also used to reproduce quantitatively the experimental difference in excess Mg2+ between N and I states. On the basis of these experiments and calculations, I state compaction appears to enhance Mg2+-I state interaction free energies by 10-20%, but this enhancement is at most 5% of the overall Mg2+-associated stabilization free energy for this rRNA fragment.  相似文献   
19.

One of the most remarkable natural plants is Vaccaria hispanica (Mill.) Rauschert, which has a high economic, medicinal and industrial potential due to its valuable compounds. However, it is mostly an underused plant worldwide. To implement doubled haploid technology in plant breeding programs and exploit its potential, first knowing the particulars of the species is necessary. This study was aimed to explore the androgenic potential of different wild Turkish V. hispanica genotypes collected from different Turkish regions, as a starting point to identify bottlenecks to solve in future studies. As to induction of microspore embryogenesis, nearly all of them responded, with efficiencies reaching 300 embryos/100 buds in some cases. However, we also found three main bottlenecks. First, the presence of foam-producing saponins in flowers prevented an efficient isolation of microspores. Second, embryos showed a reduced ability to germinate. Third, a dense network of hairy roots prevented the formation of a true, fully functional root system. Together, these drawbacks led to the production of very few DH plants. The presence of rhizogenic endophytes may be the cause of most of these problems, which opens the door for possible solutions.

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20.
The current study was conducted to determine whether there is a relation between hypertension and two different polymorphisms, including C1562T of the Matrix metalloproteinase-9 (MMP-9) gene and C677T of the methylenetetrahydrofolate reductase (MTHFR) gene. Genomic DNA obtained from 224 persons (125 patients with hypertension and 99 healthy controls) were used in the study. Polymorphisms were determined by using polymerase chain reaction-restriction fragment length polymorphism and electrophoresis. The results were statistically analyzed and were found to be statistically significant. The frequencies of the C1562T genotypes were found to be, in controls CC 75.8 % and CT 24.2 % and in patients CC 71.2 %, and CT 28.8 %. The frequencies of C677T genotype were found to be, in controls CC 56.6 %, CT 38.4 and TT 5.1 % in controls and in patients CC 52 %, CT 30.4 % and TT 17.6 %. In conclusion, we may suggest that there is no relation between the essential hypertension and C1562T polymorphism of MMP-9 gene; on the other hand C677T polymorphism (genotype TT) of MTHFR gene can be regarded as a genetic indicator for the development of essential hypertension.  相似文献   
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