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721.
Joanna M.G. Souza-Fabjan Alexsandra F. Pereira Carlos H.S. Melo Deisy J.D. Sanchez Eunice Oba Pascal Mermillod Luciana M. Melo Dárcio I.A. Teixeira Vicente J.F. Freitas 《Reproductive biology》2013,13(4):325-332
The Canindé breed of goats (Capra hircus) is currently endangered. The aims of this study were to characterize the estrus behavior, ovulatory responses and progesterone profiles, and to evaluate the in vitro embryo production (IVP) in this breed. In Experiment 1, ten nulliparous and seven pluriparous females received medroxyprogesterone acetate (MAP)-containing sponges (60 mg) plus 75 μg d-cloprostenol for estrus synchronization and their reproductive parameters were evaluated. In Experiment 2, oocytes obtained by laparascopy from hormonally stimulated females (n = 15) were used for IVP. There was no difference (p > 0.05) between nulliparous and pluriparous goats in terms of estrus response (40.0% vs. 85.7%), time from progestagen sponge removal to the onset of estrus (62.0 ± 15.5 vs. 50.7 ± 19.2 h; mean ± SEM), duration of estrus (25.0 ± 16.1 vs. 30.0 ± 15.1 h), percentage of ovulating animals (60.0% vs. 85.7%), number of ovulations (1.2 ± 0.4 vs. 1.3 ± 0.8), and diameter of the preovulatory follicle (5.8 ± 0.5 vs. 6.1 ± 0.3 mm). Progesterone concentrations were also similar (p > 0.05) in both groups. During laparoscopic recovery, there were average 12.2 aspirated follicles and 9.1 oocytes per goat, resulting in a high recovery rate (74.3%, 182/245). A total of 78 embryos were produced (51.0%). The mean number of cells in the blastocysts at day 7 of in vitro culture was 170.3 ± 12.5. In conclusion, nulliparous and pluriparous Canindé goats exhibited similar reproductive profiles. It was possible to produce embryos in vitro, allowing the instigation of an embryo bank for preservation of this breed. 相似文献
722.
Tamura M Sebastian S Yang S Gurates B Ferrer K Sasano H Okamura K Bulun SE 《The Journal of biological chemistry》2002,277(29):26208-26216
723.
K+ efflux from tobacco (Nicotiana tabacum L, cv. Samsun NN)leaf discs into the external medium was increased and the membranepotential (Em) changed in the positive direction with a changein pH from 8.0 to 4.0. Em was affected by the external concentrationof KCl, greatly decreasing with a change in concentration from1 mM to 100 mM. The equilibrium potential of the membrane forK+ (Ek) was decreased in a Nernst fashion with increasing externalconcentrations of KCl. Ek is more positive than Em above ca.50 µM KCl. Most of the experiments were carried out underconditions in which the difference between the electrochemicalpotential for K+ on the inside to the outside of the cell (µkis positive. Thus, K+ may passively flow to the outside of thecells accompanied by the depolarization of the membrane. Abscisic acid (ABA) increased the K+ efflux under conditionsof passive transport. K+ efflux was accelerated with an increasingconcentration of ABA, being maximal at 104 M103M. This acceleration was due to the enhancement of the potassiummotive force (µk/F) which is the force causing the netpassive transport of K+. The membrane potential was decreasedfrom 205 mV to 170 mV by 2 x 104 M ABAwithin 10 min. The depolarization was not transient, being lostfor at least 3 hr. These results show that ABA accelerated passive K+ efflux, whichaccompanied depolarization of the membrane. (Received June 22, 1981; Accepted August 24, 1981) 相似文献
724.
Shintaro Hirata Kazuyoshi Saito Satoshi Kubo Shunsuke Fukuyo Yasushi Mizuno Shigeru Iwata Masao Nawata Norifumi Sawamukai Kazuhisa Nakano Kunihiro Yamaoka Yoshiya Tanaka 《Arthritis research & therapy》2013,15(5):R135
Introduction
Evidences of biologics-free disease control after discontinuing adalimumab (ADA) in rheumatoid arthritis (RA) patients in clinical practice have not been sufficiently investigated. Purpose of this study is to investigate whether disease activity score 28 (DAS28)- erythrocyte sedimentation rate (ESR) remission was preserved after discontinuation of ADA in patients with RA.Methods
This is an observational but not a randomized controlled study. Among 197 RA patients who initiated with combination of ADA with concomitant MTX, 69 (35%) acquired DAS28 (ESR) < 2.6 for at least 24 weeks. Of those 69 patients, 51 went on ADA discontinuation with their consent, and finally 50 of those with follow-up of > 24 weeks were evaluated. The effect of discontinuing ADA on clinical disease activity, functional disability and radiographic progression were evaluated by DAS28 (ESR), the clinical disease activity index (CDAI) and the simplified disease activity index (SDAI), by a health assessment questionnaire-disability index (HAQ-DI) and by the modified total Sharp score (mTSS), respectively.Results
The mean age of the participants was 59.5 years with the mean disease duration of 7.1 years. Out of the 50 patients, 29 (58%) were maintained in DAS28 (ESR) < 2.6 at 24 weeks after discontinuing ADA. A logistic regression analysis showed that DAS28 (ESR) at baseline significantly predicted a DAS28 (ESR) < 2.6 maintained after discontinuation of ADA, and a receiver-operating characteristic (ROC) analysis showed that the cut-off value of DAS28 (ESR) at discontinuation was 2.16. The mean HAQ-DI at six months after discontinuing ADA was 0.1 in patients who kept in DAS28 (ESR) < 2.6, and 94.9% (37/39) showed no evidence of radiographic progression (> 0.5 per year of a change in mTSS) at 1 year.Conclusions
It was possible to maintain DAS28 (ESR) < 2.6 after discontinuation of ADA without functional and radiographic progression and very low DAS28 (ESR) at the discontinuation was associated with successful ADA-free DAS28 (ESR) < 2.6 in patients with RA.Trial registration
University Hospital Medical Information Network Identifier: UMIN000006669. 相似文献725.
726.
Neuroprotective effect of sonic hedgehog up-regulated in Schwann cells following sciatic nerve injury 总被引:1,自引:0,他引:1
Hashimoto M Ishii K Nakamura Y Watabe K Kohsaka S Akazawa C 《Journal of neurochemistry》2008,107(4):918-927
The physiological roles of sonic hedgehog (Shh) have been intensively characterized in development of various organs. However, their functions in adult tissues have not been fully elucidated. We investigated the expression and the potential function of Shh in crush-injured adult rat sciatic nerves. The Shh expression was up-regulated in Schwann cells adjacent to the injured site. The time-course analyses of various neurotrophic factors revealed the up-regulation of Shh mRNA followed by that of brain-derived neurotrophic factor (BDNF) mRNA. The continuous administration of cyclopamine, a hedgehog signal inhibitor, to the injured site suppressed the increase of BDNF expression and deteriorated the survival of motor neurons in lumbar spinal cord. Treatment of exogenous Shh in cultured Schwann cells enhanced the BDNF expression. The BDNF promoter activity (exon I and II) was increased in IMS32 cells co-transfected with Shh and its receptor Smoothened. These findings imply that the up-regulated expression of Shh in Schwann cells may play an important role in injured motor neurons through the induction of BDNF. 相似文献
727.
Masaaki Sugiyama Yasuhiro Arimura Kazuyoshi Shirayama Risa Fujita Yojiro Oba Nobuhiro Sato Rintaro Inoue Takashi Oda Mamoru Sato Richard?K. Heenan Hitoshi Kurumizaka 《Biophysical journal》2014,106(10):2206-2213
Nucleosomes containing a human histone variant, H2A.B, in an aqueous solution were analyzed by small-angle neutron scattering utilizing a contrast variation technique. Comparisons with the canonical H2A nucleosome structure revealed that the DNA termini of the H2A.B nucleosome are detached from the histone core surface, and flexibly expanded toward the solvent. In contrast, the histone tails are compacted in H2A.B nucleosomes compared to those in canonical H2A nucleosomes, suggesting that they bind to the surface of the histone core and/or DNA. Therefore, the histone tail dynamics may function to regulate the flexibility of the DNA termini in the nucleosomes. 相似文献
728.
SEK-1 MAPKK mediates Ca2+ signaling to determine neuronal asymmetric development in Caenorhabditis?elegans 下载免费PDF全文
Miho Tanaka-Hino Alvaro Sagasti Naoki Hisamoto Masato Kawasaki Shunji Nakano Jun Ninomiya-Tsuji Cornelia I. Bargmann Kunihiro Matsumoto 《EMBO reports》2002,3(1):56-62
The mitogen-activated protein kinase (MAPK) pathway is a highly conserved signaling cascade that converts extracellular signals into various outputs. In Caenorhabditis elegans, asymmetric expression of the candidate odorant receptor STR-2 in either the left or the right of two bilaterally symmetrical olfactory AWC neurons is regulated by axon contact and Ca2+ signaling. We show that the MAPK kinase (MAPKK) SEK-1 is required for asymmetric expression in AWC neurons. Genetic and biochemical analyses reveal that SEK-1 functions in a pathway downstream of UNC-43 and NSY-1, Ca2+/calmodulin-dependent protein kinase II (CaMKII) and MAPK kinase kinase (MAPKKK), respectively. Thus, the NSY-1–SEK-1–MAPK cascade is activated by Ca2+ signaling through CaMKII and establishes asymmetric cell fate decision during neuronal development. 相似文献
729.
730.
Ishitani T Takaesu G Ninomiya-Tsuji J Shibuya H Gaynor RB Matsumoto K 《The EMBO journal》2003,22(23):6277-6288
The cytokines IL-1 and TNF induce expression of a series of genes that regulate inflammation through activation of NF-kappaB signal transduction pathways. TAK1, a MAPKKK, is critical for both IL-1- and TNF-induced activation of the NF-kappaB pathway. TAB2, a TAK1-binding protein, is involved in IL-1-induced NF-kappaB activation by physically linking TAK1 to TRAF6. However, IL-1-induced activation of NF-kappaB is not impaired in TAB2-deficient embryonic fibroblasts. Here we report the identification and characterization of a novel protein designated TAB3, a TAB2-like molecule that associates with TAK1 and can activate NF-kappaB similar to TAB2. Endogenous TAB3 interacts with TRAF6 and TRAF2 in an IL-1- and a TNF-dependent manner, respectively. Further more, IL-1 signaling leads to the ubiquitination of TAB2 and TAB3 through TRAF6. Cotransfection of siRNAs directed against both TAB2 and TAB3 inhibit both IL-1- and TNF-induced activation of TAK1 and NF-kappaB. These results suggest that TAB2 and TAB3 function redundantly as mediators of TAK1 activation in IL-1 and TNF signal transduction. 相似文献