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1.
Development of bovine oocytes reconstructed with a nucleus from growing stage oocytes after fertilization in vitro 总被引:2,自引:0,他引:2
The developmental capacity of reconstructed bovine oocytes that contained nuclei from growing stage oocytes, 70-119 microm in diameter, was assessed after fertilization in vitro. Nuclei from growing stage oocytes of adult ovaries were transferred to enucleated, fully grown germinal vesicle (GV) stage oocytes. After culture in vitro, the reconstructed oocytes matured, forming the first polar body and MII plate. To supply the ability to form pronuclei, the resultant MII plate was transferred to enucleated MII oocytes, which were obtained by in vitro culture of cumulus-oocyte complexes. After fertilization in vitro, 11-15% of the reconstructed oocytes developed to morulae and blastocysts. To assess the ability to develop to term, a total of 27 late morulae and blastocysts were transferred to 19 recipient cows. Of the three cows that subsequently became pregnant, one recipient, who received two embryos derived from reconstructed oocytes with a nucleus from oocytes 100 to 109 microm in diameter, continued the pregnancy to Day 278 of gestation. This pregnancy, however, was unexpectedly a triplet pregnancy that included a set of identical twins and resulted in the premature birth of the calves, followed by death from lack of post-parturient treatment. These results show that bovine oocyte genomes are capable of supporting term development before the oocytes grow to their full size, which suggests that growing stage oocytes can be directly used as a source of maternal genomes. 相似文献
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Xyloglucan, a water-soluble food grade polysaccharide, was reported as a substrate for graft copolymerization of methyl methacrylate (MMA). Grafting PMMA (polymethyl methacrylate) with xyloglucan (XG) makes a new material with improved thermal stability and shelf life without affecting its hydrophilicity. XG was isolated from tamarind seed mucilage by aqueous extraction. Grafting of MMA was initiated by ceric ion in aqueous medium under N2 atmosphere and the progress of the reaction was monitored gravimetrically by varying different reaction parameters. Grafting of MMA onto XG was confirmed by FTIR spectroscopy, NMR spectroscopy, differential scanning calorimetric (DSC) studies, thermal gravimetric analysis (TGA) studies and scanning electron micrographs (SEMs). This material might find potential to be used in drug delivery systems. 相似文献
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Annu Makker M. M. Singh S. R. Chowdhury S. C. Maitra V. P. Kamboj 《The Journal of steroid biochemistry and molecular biology》1994,48(5-6):535-543
Alterations in nuclear and cytosolic estradiol (ER) and progesterone (PR) receptor concentration in the antimesometrial (AM) and mesometrial (M) segments of the uterus in relation to circulating hormone levels, histology and surface topography during the period of high endometrial sensitivity and development of trauma-induced decidualization in cyclic guinea pigs were investigated. The period of high endometrial sensitivity (i.e. day 5 of the estrous cycle) was characterized by elevated plasma estradiol and progesterone and their receptors in the nuclear and cytosolic fractions of the uterus. There was, however, no difference in the concentration of these receptors or the surface ultrastructure in the AM and M segments. Unilateral traumatization by scissor cut along the AM length of the uterus on day 5 of the estrous cycle induced decidual cell reaction resulting in a marked increase in weight of the decidualized (traumatized) uterine horn with advancing decidualization to reach maximum levels (926% of the contralateral nontraumatized uterine horn) 7 days after traumatization. This was associated with decidual transformation and a marked increase in nuclear and cytosolic ER and PR concentration in the AM segment of the traumatized uterine horn. An increase in receptor concentration in the M segment of the traumatized uterine horn or the AM segment of the nontraumatized uterine horn was transitory and of a low order. Receptor concentration in the M segment of the nontraumatized uterine horn remained low throughout days 8–12 of the cycle. Findings indicate a possible role of both estradiol and progesterone in induction of endometrial sensitivity and development and maintenance of decidua in the guinea pig. 相似文献
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Spermatogonial metaphase chromosomes were examined in two dragonfly species, Somatochlora metallica (Cordulidae) and Aeshna grandis (Aeshnidae), and the behaviour of male meiotic chromosomes was studied in S. metallica. Both in S. metallica and A. grandis the male mitotic metaphase chromosomes from cells treated with colchicine consisted of two equidistantly aligned chromatids, showing no primary constriction. In meiosis the chromosomes of S. metallica males showed telokinetic activity during the first meiotic division, and kinetic activity was restricted in the middle parts of chromosomes during the second division. The kinetic behaviour of the chromosomes both in mitosis and meiosis showed that they were holocentric. One chiasma arises interstitially in each bivalent in S. metallica male meiosis. The chiasmata retain their interstitial position at metaphase I and do not terminalize. At metaphase I bivalents co-orient with homologous telomere regions towards the opposite poles. Thus genuine dyads segregate at the first anaphase. Meiosis in these male dragonflies is thus pre-reductional or conventional, not post-reductional or inverted, as has been previously proposed. 相似文献
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Mittal RD Singh G Srivastava A Pradhan M Kesari A Makker A Mittal B 《Annales de génétique》2004,47(4):331-337
Azoospermia factor locus (AZF) is assumed to contain the genes responsible for spermatogenesis. Deletions in these genes are thought to be pathologically involved in some cases of male infertility associated with azoospermia or oligozoospermia. An attempt was made to establish the prevalence of micro-deletions on the Y chromosome in 79 infertile North Indians with azoospermia and oligozoospermia. Detail clinical examinations as well as endocrinological parameters were also done. Polymerase chain reaction (PCR) micro-deletion analysis was done in 79 infertile men. For this, genomic DNA was extracted from the peripheral blood. Seven sets of primers were used encompassing AZFa, AZFb and AZFc regions. Micro-deletions in five of the 79 cases (6.3%) showed deletions of at least one of the STS markers. Deletions were detected with known and unknown aetiology and at least in one of the infertile male with varicocele. AZF micro-deletions seen in idiopathic infertile males suggest the need for molecular screening in non-idiopathic cases. 相似文献
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Khajuria Annu Thusu Neelima Zutshi Ushu Bedi K.L. 《Molecular and cellular biochemistry》1998,178(1-2):113-118
The plasma-borne long-chain free fatty acids (FFA) enter skeletal muscle cells. Upon entering they are oxidized or esterified and a fraction remains free (non-esterified). The data on free fatty acids in skeletal muscles remain highly controversial. Furthermore, the composition of individual fatty acids in various lipid fractions including free fatty acids, monoglyceride and diglyceride in muscles has not been characterized. Also data on the composition of fatty acids esterified into muscle triglycerides and phospholipids are incomplete. The present study was undertaken to examine a composition of fatty acids in lipid fractions of different skeletal muscle types. For this purpose, samples of the rat soleus, red and white portions of gastrocnemius were excised, trimmed of visible fat and fascias and immediately frozen in liquid nitrogen. Samples were then pulverized and, lipids were extracted and fractionated by thin-layer chromatography. Individual long-chain fatty acids in different fractions were identified, characterized and quantitated by gas-liquid chromatography. FFA composition in the plasma was also determined. The total FFA content in the soleus, red and white gastrocnemius was 69.1 ± 10.8, 49.0 ± 13.6 and 22.7 ± 8.6 nmol/g, respectively. Palmitic and oleic acids were the major fatty acids in the muscles FFA fraction. Monoglyceride fraction of each muscle contained palmitic, stearic and linoleic acid as the major fatty acids, Diglyceride fraction contained mostly palmitic and oleic acid whereas triglyceride fraction mostly palmitic and linoleic acid.. The fraction of phospholipids was composed mostly of palmitic and linoleic acid but contained also considerable percentage of archidonic acid. Total plasma FFA/muscle FFA ratio depended on a muscle type and was: 2.4 in the soleus, 3.5 in the red and 7.4 in the white gastrocnemius. This assured transport of FFA to the myocytes. However, there were great differences in the ratio between particular FFA within the same muscle as well between the muscles. It indicates that individual FFA are either selectively transported from the plasma to the muscles or selectively used within the myocytes or both. 相似文献
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S Midha M Ranjan V Sharma A Kumari PK Singh S Korpole PB Patil 《Journal of bacteriology》2012,194(16):4468
We report the 1.8-Mb genome sequence of Pediococcus pentosaceus strain IE-3, isolated from a dairy effluent sample. The whole-genome sequence of this strain will aid in comparative genomics of Pediococcus pentosaceus strains of diverse ecological origins and their biotechnological applications. 相似文献
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Arora P Sindhu A Dilbaghi N Chaudhury A Rajakumar G Rahuman AA 《Journal of cellular and molecular medicine》2012,16(9):1991-2000
Nanotechnology is a fast growing area of research that aims to create nanomaterials or nanostructures development in stem cell and tissue-based therapies. Concepts and discoveries from the fields of bio nano research provide exciting opportunities of using stem cells for regeneration of tissues and organs. The application of nanotechnology to stem-cell biology would be able to address the challenges of disease therapeutics. This review covers the potential of nanotechnology approaches towards regenerative medicine. Furthermore, it focuses on current aspects of stem- and tissue-cell engineering. The magnetic nanoparticles-based applications in stem-cell research open new frontiers in cell and tissue engineering. 相似文献