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11.
Naz M. Aghatabay A. Ba A. Kircali G. en M.B. Yaziciolu F. Gücin B. Dülger 《European journal of medicinal chemistry》2009,44(11):4681-4689
Series of new mixed aza-oxo-thia macrocyclic ligands 1,9(2,6)-ditriazina-2,8,10,16-tetraaza-3,7,11,15-tetraoxo-5,13-dithia-cyclohexadecaphan-14,94-diphenyl (L1); 1,10(2,6)-ditri azina-2,9,11,18-tetraaza-3,8,12,17-tetraoxo-5,6,14,15-tetrathia-cyclooctadecaphan-14,104-diphenyl (L2); 1,11(2,6)-ditriazina-2,10,12,20-tetraaza-3,9,13,19-tetraoxo-6,16-dithia-cyclocosa-phan-14,114-diphenyl (L3); 1,12(2,6)-ditriazina-2,11,13,22-tetraaza-3,10,14,21-tetraoxo-6,7,17,18-tetrathia-cyclodocosaphan-14,124-diphenyl (L4) were synthesised. The structural features of the compounds have been studied by elemental analyses, Mass, FT-Raman, FT-IR, 1H and 13C NMR spectroscopy. The antimicrobial activities of the ligands were evaluated using disk diffusion method in dimethyl sulfoxide (DMSO) as well as the minimal inhibitory concentration (MIC) dilution method, against several bacteria and yeast cultures. The obtained results from both methods were assessed in side-by-side comparison with commercial antibacterial and antifungal agents. In most cases, the compounds show strong antifungal activity in the comparison tests. Cytotoxic activities of the ligands against two different human cancer cell lines, stomach (23132/87) and lung (A549) were determined by MTT assay. DNA fragmentation assay tested cell lines were used to analyze the DNA ladder formation which is a characteristic of apoptotic cell death. The binding of the ligands with calf thymus DNA (CT-DNA) has also been investigated by absorption spectroscopy. 相似文献
12.
白内障囊外摘除术房水细菌培养的临床观察 总被引:1,自引:0,他引:1
对36例白内障囊外摘除术抽吸前房水进行细菌培养,其中16例细菌培养阳性,大多为表皮葡萄球菌,菌落的形态很小,绝大多数为10-30个/ml,无1例发生眼内炎。这提示白内障术后前房可清除少量的细菌而不发生服内感染。 相似文献
13.
Zhenlin Li Emma Colucci Charles Babinet Denise Paulin 《Neuromuscular disorders : NMD》1993,3(5-6):423-427
Desmin synthesis is restricted to cardiac, skeletal and smooth muscles. In several familial myopathies involving fibre disorganization, filamentous aggregation of desmin has been characterized. During the development of the mouse embryo, desmin is one of the first muscle proteins detected in both the heart and the somites. To identify the DNA sequences involved in the regulation of desmin gene expression a 4.5 kb 5′-flanking region of the human desmin gene has been isolated. Different mutants were used to characterize specific enhancers in vitro and in vivo. The results obtained with transgenic mice provide evidence that the 1 kb cis-regulatory sequences, functional in skeletal muscle cells in vitro, confer specific developmental control for skeletal muscles. Furthermore, distinct programmes for cardiac and skeletal muscle-specific expression of the desmin gene are revealed. 相似文献
14.
神经元性一氧化氮合酶活性在app/ps1双转基因AD模型小鼠皮质和海马的分布 总被引:2,自引:0,他引:2
本实验用 4~ 5月龄和 15~ 16月龄的 app/ ps1dtg小鼠各 5只 ,同龄野生型小鼠每个年龄组各 5只 ,用β-NADPH组织化学染色显示神经元一氧化氮合酶活性 ,刚果红组织学染色显示神经炎性斑 ,无偏性体视学计量皮质和海马神经炎斑的总体积 ,研究神经元一氧化氮合酶活性在 app/ ps1双转基因 (app/ ps1dtg) AD模型小鼠大脑皮质和海马的异常分布 ,探讨其在该模型小鼠及 AD患者脑内病理改变中的作用。结果显示 ,n NOS阳性神经元在各组小鼠皮质和海马内的分布没有区别 ,4~ 5月龄 app/ps1dtg小鼠皮质和海马可见神经炎斑 (NP)和营养不良性 NOS阳性神经突 (DTN) ;15~ 16月龄 app/ ps1dtg小鼠皮质和海马内NP的体积分别是 4~ 5月龄 app/ ps1dtg小鼠皮质 NP的 5倍 (P<0 .0 0 5 )和 8倍 (P<0 .0 0 1) ;15~ 16月龄 app/ ps1dtg小鼠皮质内 DTN的体积明显增大 (P<0 .0 1) ;且伴有 NOS阳性神经元形态的改变及海马 CA1 区 NOS阳性神经元数量的减少 (P<0 .0 5 ) ,DTN的形成与 NP呈正相关关系 (r=0 .85 ,P<0 .0 5 )。本实验结果表明 ,app/ ps1dtg小鼠能够模拟 AD患者脑内 NOS阳性神经元的病理改变 ,DTN的形成可能与 Aβ的毒性作用有关 ,DTN产生的 NO可能参与 app/ ps1dtg小鼠和 AD的神经病理过程。 相似文献
15.
Döpper S Wilflingseder D Prodinger WM Stiegler G Speth C Dierich MP Stoiber H 《European journal of immunology》2003,33(8):2098-2107
Resting CD4(+) T cells in the lymphoid tissue (LT) are essential producers of virions at the beginning of HIV infection in vivo. We previously developed a model that allowed in vitro infection of non-prestimulated T lymphocytes in the presence of autologous B lymphocytes and complement. In this study, we try to clarify the mechanism(s) responsible for virus transmission in unstimulated autologous B cell/T cell co-cultures. Ex vivo analyses of patient plasma samples revealed that HIV was opsonized. Flow cytometry showed that opsonized virus preferentially bound to complement receptor (CR)-2 on B lymphocytes in primary B cell/T cell co-cultures. As indicated by cytokine measurements and transwell experiments, soluble factors seemed to play a minor role in enabling infection. Rather, direct interaction between B and T lymphocytes and direct binding of opsonized virus to CR2 on B cells turned out to be essential for productive infection. Antibodies blocking cell-cell adhesion inhibited p24 antigen production. An anti-CR2 antibody blocking C3d-CR2 binding also significantly reduced viral replication. Since the infection of unstimulated T cells by opsonized primary HIV isolates in the presence of B cells was highly efficient independent of the tropism of the virus, this mechanism may be critical in the pathogenesis of HIV. 相似文献
16.
Seong-Keun Cho Jae-Hwan Kim Jong-Yi Park Yun-Jung Choi Jae-Il Bang Kyu-Chan Hwang Eun-Jeong Cho Sea-Hwan Sohn Sang Jun Uhm Deog-Bon Koo Kyung-Kwang Lee Teoan Kim Jin-Hoi Kim 《Developmental dynamics》2007,236(12):3369-3382
Somatic cell nuclear transfer (scNT) is a useful way to create cloned animals. However, scNT clones exhibit high levels of phenotypic instability. This instability may be due to epigenetic reprogramming and/or genomic damage in the donor cells. To test this, we produced transgenic pig fibroblasts harboring the truncated human thrombopoietin (hTPO) gene and used them as donor cells in scNT to produce first-generation (G1) cloned piglets. In this study, 2,818 scNT embryos were transferred to 11 recipients and five G1 piglets were obtained. Among them, a clone had a dimorphic facial appearance with severe hypertelorism and a broad prominent nasal bridge. The other clones looked normal. Second-generation (G2) scNT piglets were then produced using ear cells from a G1 piglet that had an abnormal nose phenotype. We reasoned that, if the phenotypic abnormality of the G1 clone was not present in the G2 and third-generation (G3) clones, or was absent in the G2 clones but reappeared in the G3 clones, the phenotypic instability of the G1 clone could be attributed to faulty epigenetic reprogramming rather than to inherent/accidental genomic damage to the donor cells. Blastocyst rates, cell numbers in blastocyst, pregnancy rates, term placenta weight and ponderal index, and birth weight between G1 and G2 clones did not differ, but were significantly (P < 0.05) lower than control age- and sex-matched piglets. Next, we analyzed global methylation changes during development of the preimplantation embryos reconstructed by donor cells used for the production of G1 and G2 clones and could not find any significant differences in the methylation patterns between G1 and G2 clones. Indeed, we failed to detect the phenotypic abnormality in the G2 and G3 clones. Thus, the phenotypic abnormality of the G1 clone is likely to be due to epigenetic dysregulation. Additional observations then suggested that expression of the hTPO gene in the transgenic clones did not appear to be the cause of the phenotypic abnormality in the G1 clones and that the abnormality was acquired by only a few of the G1 clone's cells during its gestational development. 相似文献
17.
Histamine accumulated in the ligated vagus nerve of the rat, both above and below the ligature; maximum accumulation was after 4 h. The finding is suggestive of axonal flow. Further evidence for histamine in peripheral nerves was obtained in experiments showing that the guinea-pig gut wall could be labelled with [3H]histamine. The experiments were carried out with isolated strips of stomach wall and taenia coli. Electrical stimulation released [3H]histamine from these specimens. The release could be blocked by Ca2+-free medium or by tetrodotoxin. The release was unaffected by vagal denervation or chemical sympathectomy (6-hydroxydopamine) but prevented by reserpinization. Gastrin-17 and cholecystokinin-39 released radioactivity by a tetrodotoxin-sensitive mechanism. The possible existence of a gastrin/cholecystokinin-sensitive neuronal pool of histamine in the gut wall offers a new perspective on the postulated role of histamine as a physiological stimulant of gastric acid secretion and might explain why H2-receptor antagonists block gastrin-stimulated acid secretion. 相似文献
18.
V. I. Shumakov V. N. Blyumkin R. A. Babikova V. P. Fedotov G. G. Tsertsvadze N. V. Sadovnikova L. I. Ul'yanova 《Bulletin of experimental biology and medicine》1979,88(2):903-905
Cultures of islets cells were obtained from the cadaveric pancreas of 16–25-week human fetuses. During culture two waves of mitotic activity were observed. An increase in the insulin concentration in the culture medium took place after a wave of mitotic activity.Department of Artificial Organs and Assisted Circulation, Laboratory of Pathomorphology, Scientific-Research Institute of Transplantation and Artificial Organs, Ministry of Health of the USSR. Laboratory of Biological Standardization of Hormones, Institute of Experimental Endocrinology and Hormone Chemistry, Academy of Medical Sciences of the USSR. Maternity Home No. 26, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 8, pp. 202–204, August, 1979. 相似文献
19.
Espinosa M Noé G Troncoso C Ho SB Villalón M 《Human reproduction (Oxford, England)》2002,17(8):1964-1972
BACKGROUND: Cervical mucus is a heterogeneous mixture of water, ions and mucins that form a hydrophilic polymer gel. Mucins, the main components of mucus, are condensed inside secretory granules and swell to become a hydrogel after exocytosis. Using human cervical secretory cell primary cultures, the effect of [Ca(2+)] and [H(+)] on the swelling velocity of mucin granules was investigated in vitro. METHODS and RESULTS: Immunocytochemistry demonstrated that estrogen and progesterone receptors were expressed in cultured secretory cells along with mucins type 1, 4, 5AC and 5B. Exocytosis of secretory cells, recorded by videomicroscopy, showed that during swelling, the radius of the secretory granule matrix followed first-order kinetics. An increase in extracellular [Ca(2+)] from 1 to 4 mmol/l or a reduction in pH from 7.4 to 6.5 was seen to produce a significant decrease in the velocity of swelling of the secretory granule matrix. CONCLUSIONS: The inverse relationship observed between the diffusion of the granular matrix and the extracellular [Ca(2+)] or [H(+)] suggested that changes in cation concentration might drastically affect the swelling characteristics of mucins and provide a control mechanism for the observed viscoelastic properties of mucus. 相似文献
20.
Summary Several protocols are presented for preparation and transfection of Baculovirus and plasmid DNAs into Lepidopteran insect cells using the calcium-phosphate co-precipitation technique. Important parameters for optimum efficiency include the inherent susceptibility of the recipient cell line for transfection, and the method of preparation of viral and plasmid DNAs. The protocols presented provide reproducible high efficiencies for transfection of several Lepidopteran cell lines. 相似文献