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201.
Although cervical cancer is preventable with early detection, it remains the second most common malignancy among women. An understanding of how proteins change in their expression during a particular diseased state such as cervical cancer will contribute to an understanding of how the disease develops and progresses. Potentially, it may also lead to the ability to predict the occurrence of the disease. With this in mind, we aimed to identify differentially expressed proteins in the plasma of cervical cancer patients. Plasma from control, cervical intraepithelial neoplasia (CIN) grade 3 and squamous cell carcinoma (SCC) stage IV subjects was resolved by two-dimensional gel electrophoresis and the resulting proteome profiles compared. Differentially expressed protein spots were then identified by mass spectrometry. Eighteen proteins were found to be differentially expressed in the plasma of CIN 3 and SCC stage IV samples when compared with that of controls. Competitive ELISA further validated the expression of cytokeratin 19 and tetranectin. Functional analyses of these differentially expressed proteins will provide further insight into their potential role(s) in cervical cancer-specific monitoring and therapeutics.  相似文献   
202.
Phosphorus (P) starvation is highly notorious for limiting plant growth around the globe. To combat P-starvation, plants constantly sense the changes in their environment, and elicit an elegant myriad of plastic responses and rescue strategies to enhance P-solublization and acquisition from bound soil P-forms. Relative growth responses, P-solublization and P- acquisition ability of 14 diverse Brassica cultivars grown with sparingly soluble P-sources (Rock-P (RP) and Ca3(PO4)2 (TCP)) were evaluated in a solution culture experiment. Cultivars showed considerable genetic diversity in terms of biomass accumulation, concentration and contents of P and Ca in shoots and roots, P-stress factor (PSF) and P use efficiency. Cultivars showed variable P-stress tolerance, and cultivars depicting low PSF and high P-efficiency values were better adaptable to P-starvation. In experiment 2, after initial feeding on optimum nutrition for 12 d after transplanting (DAT), class-I (low P-tolerant (Oscar and Con-II)) and class-II (low P-sensitive (Gold Rush and RL-18)) cultivars were exposed to P-free environment for 25 d. All of the cultivars remobilized P from above ground parts to their roots during growth in P-free environment, the magnitude of which was variable in tested cultivars. P-concentrations ([P]s) at 37 DAT were higher in developing compared with developed leaves. Translocation of absorbed P from metabolically inactive to active sites in P- stressed plants may have helped class-I cultivars to establish a better rooting system, which provided a basis for enhanced P-utilization efficiency (PUE) and tolerance against P-stress. By supplying TCP and RP spatially separated from other nutrients in split root study, class-I cultivars were still able to mobilize RP and TCP more efficiently compared with class-II cultivars. To compare the growth behavior under P-stress, cultivars were grown in pots for 41 d after sowing, using a soil low in P (NaHCO3-extractable P = 3.97 mg/kg, M  相似文献   
203.
Non-mycorrhizal Brassica does not produce specialized root structures such as cluster or dauciform roots but is an effective user of P compared with other crops. In addition to P-uptake, utilization and remobilization activity, acquisition of orthophosphate (Pi) from extracellular sparingly P-sources or unavailable bound P-forms can be enhanced by biochemical rescue mechanisms such copious H+-efflux and/or carboxylates exudation into rhizosphere by roots via plasmalemma H+ ATPase and anion channels triggered by P-starvation. To visualize the dissolution of sparingly soluble Ca-phosphate (Ca-P), newly formed Ca-P was suspended in agar containing other essential nutrients. With NH4+ applied as the N source, the precipitate dissolved in the root vicinity can be ascribed to rhizosphere acidification, whereas no dissolution occurred with nitrate nutrition. To observe in situ rhizospheric pH changes, images were recorded after embedding the roots in agar containing bromocresol purple as a pH indicator. P-tolerant cultivar showed a greater decrease in pH than the sensitive cultivar in the culture media (the appearance of typical patterns of various colors of pH indicator in the root vicinity), and at stress P-level this acidification was more prominent. In experiment 2, low P-tolerant class-I cultivars (Oscar and Con-II) showed a greater decrease in solution media pH than low P-sensitive class-II (Gold Rush and RL-18) cultivars, and P-contents of the cultivars was inversely related to decrease in culture media pH. To elucidate P-stress- induced remodeling and redesigning in a root architectural system, cultivars were grown in rhizoboxes in experiment 3. The elongation rates of primary roots increased as P-supply increased, but the elongation rates of the branched zones of primary roots decreased. The length of the lateral roots and topological index values increased when cultivars were exposed to a P-stress environment. To elucidate Pi-uptake kinetics, parameters related to P influx: maximal  相似文献   
204.
This study describes comparison between IPTG and lactose induction on expression of caprine growth hormone (cGH), enhancing cell densities of Escherichia coli cultures and refolding the recombinant cGH, produced as inclusion bodies, to biologically active state. 2–3 times higher cell densities were obtained in shake flask cultures when induction was done with lactose showing almost same level of expression as in case of IPTG induction. With lactose induction highest cell densities were achieved in TB (OD600 16.3) and M9NG (OD600 16.1) media, producing 885 and 892 mg cGH per liter of the culture, respectively. Lactose induction done at mid-exponential stage resulted in a higher cell density and thus higher product yield. cGH over-expressed as inclusion bodies was solubilized in 50 mM Tris–Cl buffer (pH 12.5) containing 2 M urea, followed by dilution and lowering the pH in a step-wise manner to obtain the final solution in 50 mM Tris–Cl (pH 9.5). The cGH was purified by Q-Sepharose chromatography followed by gel filtration with a recovery yield of 39% on the basis of total cell proteins. The product thus obtained showed a single band by SDS–PAGE analysis. MALDI-TOF analysis showed a single peak with a mass of 21,851 dalton, which is very close to its calculated molecular weight. A bioassay based on proliferation of Nb2 rat lymphoma cells showed that the purified cGH was biologically active.  相似文献   
205.
In this paper, boselaphine material from several localities in the area of the Hasnot Pakistan, is described, identified, and discussed. Four species that belong to three different genera of the tribe Boselaphini have been found: Selenoportax vexillarius, S. lydekkeri, Pachyportax latidens and Eotragus sp. Eotragus sp. is reported for the first time from the Hasnot and consequently from other Upper Middle Siwalik sediments of Pakistan and equivalent strata of the world, extending the range of the genus from the Lower to the Middle Siwaliks. Reviewing the Siwaliks’ Selenoportax species, S. dhokpathanensis Akhtar and S. tatrotensis Akhtar are synonymized with S. lydekkeri and S. vexillarius, respectively.  相似文献   
206.

Background  

TATA-box-binding protein 2 (TBP2/TRF3) is a vertebrate-specific paralog of TBP that shares with TBP a highly conserved carboxy-terminal domain and the ability to bind the TATA box. TBP2 is highly expressed in oocytes whereas TBP is more abundant in embryos.  相似文献   
207.
Tomato is one of the most consumed vegetables in the world. Diseases are the number one concern in the development of high-yield and disease-resistant tomato hybrids which is the foremost priority of breeders. Present study was conducted (1) to develop DNA-based markers for genetic confirmation of tomato F1 hybrids, (2) to utilize sequenced characterized amplified region (SCAR) marker linked to the Ph-3 gene for Phytophthora infestans resistance in tomato and (3) to evaluate male and female parental genotypes and their F1 hybrids against late blight (LB) and cucumber mosaic virus (CMV). For molecular studies, 58 previously reported markers including RAPDs (10), SCAR (01), EST-SSR (01) and SSR (46) were applied. The SCAR marker clearly differentiated the LB3 and LB4 from Roma and T-1359 and provided evidence for Ph-3 gene. The SCAR marker was able to confirm the Ph-3 gene in the hybrids Roma × LB4, Roma × LB3, Riogrande × LB2, Riogrande × LB3 and Roma × LB7. Out of several tested primers, SSR-22 proved useful for genetic confirmation of F1 hybrid TMS1 × Money Maker (MM). For LB, tested hybrids/genotypes were ranked as susceptible to highly susceptible with different infection percentage (IP). However, the pace of symptom development was slower in hybrid Rio × LB2, 45% IP after 10 days of inoculation compared with 85% disease in one of the parent genotypes (Riogrande). None of the tested genotypes was found resistant; however, TMS1 responded as tolerant against CMV using mechanical inoculation. Under natural field conditions, TMS1 was found resistant while hybrids TMS1 × Naqeeb and TMS1 × MM were tolerant where as others were found to be susceptible. In conclusion, all tomato hybrids were genetically confirmed using DNA-based markers. SCAR marker was useful for marker-assisted confirmation of the Ph-3 gene in parental lines and hybrids; however, this gene was unable to provide protection against the local population of P. infestans.  相似文献   
208.
The Myh11‐CreERT2 mouse line (Cre+) has gained increasing application because of its high lineage specificity relative to other Cre drivers targeting smooth muscle cells (SMCs). This Cre allele, however, was initially inserted into the Y chromosome (X/YCre+), which excluded its application in female mice. Our group established a Cre+ colony from male ancestors. Surprisingly, genotype screening identified female carriers that stably transmitted the Cre allele to the following generations. Crossbreeding experiments revealed a pattern of X‐linked inheritance for the transgene (k > 1000), indicating that these female carries acquired the Cre allele through a mechanism of Y to X chromosome translocation. Further characterization demonstrated that in hemizygous X/XCre+ mice Cre activity was restricted to a subset arterial SMCs, with Cre expression in arteries decreased by 50% compared to X/YCre+ mice. This mosaicism, however, diminished in homozygous XCre+/XCre+ mice. In a model of aortic aneurysm induced by a SMC‐specific Tgfbr1 deletion, the homozygous XCre+/XCre+ Cre driver unmasked the aortic phenotype that is otherwise subclinical when driven by the hemizygous X/XCre+ Cre line. In conclusion, the Cre allele carried by this female mouse line is located on the X chromosome and subjected to X‐inactivation. The homozygous XCre+/XCre+ mice produce uniform Cre activity in arterial SMCs.  相似文献   
209.
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   
210.
Consolida (dc .) S. F. Gray belongs to Ranunculaceae. The genus includes about 52 species worldwide. Here we report the diploid chromosome number and chromosome size and morphology for six Consolida species. For C. anthoroidea, C. leptocarpa, C. paradoxa and C. rugulosa the diploid chromosome number is reported for the first time. All investigated species have a diploid chromosome number of 2n = 2x = 16, except for C. persica having 2n = 2x = 14. The karyotypes of all six taxa are asymmetric, consisting of all four major chromosome types: metacentric, submetacentric, subtelocentric and telocentric chromosome type. However, considering the karyotype formula, all six species could be distinguished. In all taxa, metacentric chromosome pair 1 possesses a satellite. The only exception is C. rugulosa having an additional satellite positioned on metacentric chromosome pair 2. Karyotype data allow the separation of Aconitella from Consolida. Karyotype data plus morphological evidence support the reduction of C. paradoxa to formae level of C. rugulosa. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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