Optimization of culture medium for cloned bovine embryos and its influence on pregnancy and delivery outcome

This study was conducted to establish an effective culture system for supporting in vitro development of cloned bovine embryos and to evaluate whether improved development in the optimal culture system could contribute to enhancing pregnancy and delivery outcomes after transfer. Enucleated oocytes at the metaphase II stage were reconstructed with serum-starved ear fibroblasts and cloned embryos were subsequently cultured for 168 h in vitro. In Experiment 1, cloned embryos were cultured in either modified Charles Rosenkrans 2 amino acid medium (mCR2aa) or modified synthetic oviduct fluid medium (mSOF). More (P < 0.05) 2-cell embryos (78% versus 92%), morulae (51% versus 69%) and blastocysts (2% versus 39%) were obtained after culture in mSOF than after culture in mCR2aa. In Experiment 2, cloned embryos were successively cultured in mSOF supplemented with various macromolecules during different periods of culture. A successive culture of oocytes in BSA-containing medium for 72 h and then in FBS-containing medium for the next 96 h yielded a higher rate of blastocyst formation (49% versus 25-36%) than other combinations (BSA to BSA or PVA to PVA, BSA or FBS). This macromolecule supplementation also significantly increased the number of total blastomeres (117.3 cells/blastocyst) and inner cell mass cells (ICM, 49.7 cells/blastocyst), and the ratio of ICM cells to trophoblast cells (TB, 0.98). In Experiment 3, a total of 85 blastocysts obtained from each 2-step culture were transferred individually to recipient cows at the end of the culture period and 32 pregnancies (38%) were diagnosed on Day 60 after transfer. However, no (P > 0.05) significant differences due to culture were apparent in the pregnancy outcome. Although six calves were produced using the 2-step culture regime of either BSA-BSA or PVA-FBS, no calves were produced using the successive culture of BSA then FBS, which optimized preimplantation development. In conclusion, mSOF has more potential to support the development of clone embryos than mCR2aa, and successive supplementation of BSA and FBS to mSOF further promotes blastocyst formation. However, enhanced development in vitro might not directly contribute to improving pregnancy outcomes.     

NF-kappaB activates fibronectin gene expression in rat hepatocytes

Resveratrol (RSVL), an edible polyphenolic stilbene, claims a myriad of cardiovascular benefits. However, the molecular underpinnings of such actions are poorly understood. Currently, in sheep coronary arteries (SCA), RSVL markedly (threefold) enhanced cGMP formation (t(1/2): 6.5 min; EC(50): 3 microM). This response was not abrogated by the phosphodiesterase inhibitor (IBMX, 0.5 mM), but was partly sensitive (20-30%) to either removal of the endothelium, treatment with the nitric oxide synthase-inhibitor (L-NMMA, 10 microM), or with the soluble GC (sGC)-inhibitor (ODQ, 10 microM). In membrane preparations from denuded SCA, either RSVL or the pGC agonist atrial natriuretic peptide (ANP, 0.1-1 microM) activated GC in the particulate, but not in the soluble, membrane fraction. By contrast, the nitric oxide donor, sodium nitroprusside (SNP, 1-10 microM), stimulated GC only in the soluble fraction. Further, pretreatment with RSVL partly desensitized the ANP response, but was additive to that of SNP. In arterial tension studies, RSVL relaxed PGF(2alpha)-precontracted denuded rings in a concentration-dependent manner, a response that was markedly enhanced (approximately 18 fold) in the presence of IBMX. Conversely, precontraction with phorbol ester, which also desensitizes pGC, blunted relaxations to RSVL but not to forskolin or SNP. These findings demonstrate that RSVL increases cGMP in coronary arteries, mostly by activation of pGC. This pathway triggers vasorelaxant responses that remain effective in endothelium-disrupted arteries.     

伯乐树种子不同条件贮藏下前后生理比较

对3个不同地区（浙江省遂昌县、福建省浦城县和浙江江山市）的伯乐树种子形态指标进行了测定。并分别设置3种贮藏方式（A为室内湿沙环境下贮藏;B为低温（4℃）湿沙下贮藏;C为低温（4℃）封口袋中贮藏）,对贮藏前后种子的发芽率、发芽势、含水量等生理指标进行了比较研究。结果表明,浦城县地区较另外二个地区的种子狭长而扁平,且质量较小。经130d的贮藏后,3个地区的种子内淀粉含量显著下降（P〈0．05）,含水量、蛋白酶活性、淀粉酶活性、蛋白含量和可溶性糖含量则均显著升高（P〈0．05）,从而使休眠得以解除。贮藏后的发芽率和发芽势显著提高（P〈0．05）,以湿沙低温下的发芽率和发芽势为最高。     

Molecular Dissection of Bombyx mori Nucleopolyhedrovirus orf8 Gene

Viruses including baculoviruses are obligatory parasites, as their genomes do not encode all the proteins required for replication. Therefore, viruses have evolved to exploit the behavior and the physiology of their hosts and often eoevolved with their hosts over millions of years. Recent comparative analyses of complete genome sequences of baculoviruses revealed the patterns of gene acquisitions and losses that have occurred during baculovirus evolution. In addition, knowledge of virus genes has also provided understanding of the mechanism of baculovirus infection including replication, species-specific virulence and host range. The Bm8 gene of Bombyx mori nucleopolyhedrovirus (NPV) and its homologues are found only in group I NPV genomes. The Autographa californica NPV Acl6 gene is a homologue of Bm8 and, encodes a viral structural protein. It has been shown that Bm8/Ac 16 interacts with baculoviral and cellular proteins. Bm8/Ac 16 interacts with baculoviral IE1 that is facilitated by coiled coil domains, and the interaction with IE1 is important for Bin8 function. Ac16 also forms a complex with viral FP25 and cellular actin and associates with membranes via palmitoylation. These data suggested that this gene family encodes a multifunctional protein that accomplishes specific needs of group INPVs.     

2011年、2013年和2016年医院内获得性血流感染常见病原菌分布及其耐药性分析

动态监测2011年、2013年和2016年我国不同地区医院内获得性血流感染病原菌分布及耐药进展趋势。从全国10个城市回顾性收集血流感染病原菌非重复性株,采用琼脂稀释法或微量肉汤稀释法进行药物敏感性试验,采用Whonet 5.6软件对药敏试验结果进行分析。收集的2 248株血流感染病原菌中革兰阴性杆菌为1 657株 (占73.7%),革兰阳性球菌为591株 (占26.3%)。分离率排名前五的病原菌依次为大肠埃希菌 (32.6%,733株/2 248株)、肺炎克雷伯菌 (14.5%,327株/2 248株)、金黄色葡萄球菌 (10.0%,225株/2 248株)、鲍曼不动杆菌 (8.7%,196株/ 2 248株) 和铜绿假单胞菌 (6.2%,140株/2 248株)。血流感染分离的革兰阴性杆菌对抗菌药物体外敏感率较高的抗菌药物依次为粘菌素 (96.5%,1 525株/1 581株,不包括天然耐药菌株)、替加环素 (95.6%,1 375株/1 438株,不包括天然耐药菌株)、头孢他啶/克拉维酸 (89.2%,1 112株/1 246株)、阿米卡星 (86.4%,1 382株/1 599株) 和美罗培南 (85.7%,1 376株/1 605株);革兰阳性球菌对抗菌药物体外敏感率较高的抗菌药物依次为替加环素、替考拉宁和达托霉素 (敏感率均为100.0%)、万古霉素和利奈唑胺 (敏感率均为99.7%)。2011年、2013年和2016年产超广谱β-内酰胺酶肠杆菌科细菌分离率分别为50.6% (206株/407株)、49.8% (136株/273株) 和38.9% (167株/429株);碳青霉烯不敏感肠杆菌科细菌分离率分别为2.2% (9株/408株)、4.0% (16株/402株) 和3.9% (17株/ 439株);多重耐药鲍曼不动杆菌分离率分别为76.4% (55株/72株)、82.7% (43株/52株) 和87.5% (63株/72株),多重耐药铜绿假单胞菌分离率分别为9.8% (5株/51株)、20.0% (7株/35株) 和13.0% (7株/54株);甲氧西林耐药金黄色葡萄球菌的分离率分别为51.9% (41株/79株)、29.7% (19株/64株) 和31.7% (26株/82株)。屎肠球菌和粪肠球菌中高水平庆大霉素耐药株分离率分别为43.2% (48株/111株) 和40.9% (27株/66株)。碳青霉烯不敏感肠杆菌科细菌中肺炎克雷伯菌居首位,占57.1% (24株/42株) 。肠杆菌科细菌中分离出30株替加环素不敏感株,其中肺炎克雷伯菌占76.7% (23株/30株);分离出粘菌素耐药肠杆菌科细菌39株,其中大肠埃希菌、阴沟肠杆菌和肺炎克雷伯菌分别占43.6% (17株/39株)、35.9% (14株/39株) 和15.4% (6株/39株)。医院获得性血流感染病原菌主要为革兰阴性杆菌 (以大肠埃希菌和肺炎克雷伯菌为主),其对替加环素、粘菌素和碳青霉烯类药物的敏感率较高;革兰阳性球菌中分离率最高的为金黄色葡萄球菌,其次为屎肠球菌,这两种细菌对替加环素、达托霉素、利奈唑胺、万古霉素和替考拉宁的敏感率较高。粘菌素耐药肠杆菌科细菌、替加环素不敏感肠杆菌科细菌、利奈唑胺或万古霉素不敏感革兰阳性球菌的分离,警示临床高度关注,仍需动态监测耐药进展趋势。     

An Imported Case of Cystic Echinococcosis in the Liver

A 25-year-old Uzbek male presented with right upper abdominal pain for 20 days. On radiologic studies, a huge cystic mass was noticed in the right liver which was suspected as parasitic. The patient received right hepatic segmentectomy (segment 7), and the surgically resected mass was confirmed as cystic echinococcosis (CE), measuring 10.5 cm in its diameter. The inner surface of the cyst was bile-stained. The patient was discharged on the 8th hospital day, and was rechecked 6 months after the surgical intervention without any evidence of recurrence. The present report describes findings of an imported case of CE which represented ultrasound images of the ''ball of wool''.     

间断低氧对大鼠下丘脑超微结构及前增食欲素水平的影响

目的探讨睡眠中间断低氧对大鼠下丘脑前增食欲素及受体水平的影响以及下丘脑超微结构的变化。方法大鼠分成对照组、间断低氧组和持续低氧组,分别给予吸入空气,持续低氧和间断低氧气体,并在实验开始后1d、3d、1w和4w应用RT-PCR方法测定大鼠下丘脑前增食欲素及受体水平,分析其间的变化关系,电镜观察下丘脑的超微结构变化。结果与对照组和持续低氧组比较,间断低氧4w后大鼠下丘脑前增食欲素mRNA水平明显降低,受体水平升高,但在持续低氧和对照组之间无明显差异。在低氧后1d、3d、7d后大鼠下丘脑前增食欲素mRNA降低,受体水平升高,在4w后,持续低氧组则接近正常。急性持续低氧大鼠超微结构变化更严重,而慢性间断低氧变化更持久。结论慢性间断低氧可以引起下丘脑前增食欲素下降及受体水平升高,急性持续低氧也可引起上述变化,而慢性持续低氧未引起增食欲素改变;慢性间断低氧大鼠下丘脑超微结构表现为严重而持久的变化。