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21.
Katrin Trummal Külli T?nism?gi Ene Siigur Anu Aasp?llu Annika Lopp Tarvo Sillat Riste Saat Lagle Kasak Indrek Tammiste Priit Kogerman Nisse Kalkkinen Jüri Siigur 《Toxicon》2005,46(1):46-61
A novel endothelial cell apoptosis inducing metalloprotease (VLAIP) was found in the snake venom of Vipera lebetina. This metalloprotease is a heterodimeric glycoprotein with molecular mass of about 106 kDa. The protease hydrolyzes azocasein, fibrinogen and oxidized insulin B-chain. The enzyme readily hydrolyzes the Aalpha-chain and more slowly Bbeta-chain of fibrinogen. VLAIP does not cleave fibrin. The complete amino acid sequences of the two different monomers of VLAIP are deduced from the nucleotide sequences of cDNAs encoding these proteins. The full-length cDNA sequences of the VLAIP-A and VLAIP-B encode open reading frames of 616 and 614 amino acids that include signal peptide, propeptide and mature metalloproteinase with disintegrin-like and cysteine-rich domains. VLAIP belongs to the metalloprotease/disintegrin family of reprolysins and has high identity with the proteins that induce apoptosis of endothelial cells. Treatment of HUVEC cells with VLAIP induces changes in the attachment of cells to the substrate and causes cell death. We demonstrated that VLAIP inhibits endothelial cell adhesion to extracellular matrix proteins: fibrinogen, fibronectin, vitronectin, collagen I, and collagen IV. The induction of apoptosis by VLAIP was shown by means of a typical DNA fragmentation pattern of apoptotic cells as well as by monitoring phosphatidylserine externalization using annexin V-FITC staining and flow cytometric analysis. 相似文献
22.
A study in 2000-2001 of causes of death of women of reproductive age (15-49) in the West Bank, Palestinian Occupied Territories, found that 154 of the 411 deceased women aged 15-49 with known marital status were single. Death notification forms for reported deaths were analysed and verbal autopsies carried out, where possible, with relatives of the deceased women. We found important differences in the age at death and causes of death among the single and married women, which can be attributed to the disadvantaged social status of single women in Palestinian society, exacerbated by the current unstable political situation. 41% of the deceased single women were under 25 years of age at death compared to 8% of the married women. The proportion of violent deaths and suicides among the single women was almost twice as high as among the married women, mainly in those below age 25. The single women were also more likely to die from medical conditions which indicated that they faced barriers to accessing health care. The fieldwork was conducted at the height of the Intifada and the Israeli military response, with heavy restrictions on mobility, limiting the possibility of probing deeper into the circumstances surrounding sensitive deaths. More research into the socio-cultural context of single women in Palestine society is needed as a basis for intervention. 相似文献
23.
Primary fallopian tube carcinoma (PFTC) is rare, constituting about 1% of female genital tract malignancies, and little is known about its etiological, protective, risk or prognostic factors. Earlier, such factors were thought to be similar to those seen in ovarian cancer. The incidence of PFTC has been rising during the last decades, especially in higher social classes and among women in certain occupations. Parity is a strong protective factor for PFTC, with a lower incidence associated with an increasing number of deliveries. Previous sterilisation seems to offer some protection. Earlier suggestions of previous genital infections as risk factors appear not to hold. Previous cancers are frequent among PFTC patients, especially breast cancer. Second primary cancers after PFTC are also frequent, especially non-lymphoid leukemia, colorectal, breast, bladder and lung cancer. Only 4% of primary fallopian carcinomas are correctly diagnosed before operation. Treatment consists of aggressive cytoreductive surgery and adjuvant chemotherapy with a platinum-taxane combination. A high preoperative serum hCGss is a strong prognostic factor for worse prognosis. The 5-year survival rates vary between 22 and 57%. 相似文献
24.
Agustina Heredia-Martinez Guillermo Rosa-Diez Jorge R. Ferraris Anna-Karin Sohlenius-Sternbeck Carina Nihlen Annika Olsson Jon O. Lundberg Eddie Weitzberg Mattias Carlstrm Rafael T. Krmar 《Nutrients》2022,14(12)
Nitric oxide (NO) contributes to maintaining normal cardiovascular and renal function. This bioactive signalling molecule is generally formed enzymatically by NO synthase in the vascular endothelium. NO bioactivity can also be attributed to dietary intake of inorganic nitrate, which is abundant in our diet, especially in green leafy vegetables and beets. Ingested nitrate is reduced to nitrite by oral commensal bacteria and further to NO systemically. Previous studies have shown that dialysis, by means of removing nitrate and nitrite from the body, can reduce NO bioactivity. Hence, dietary intervention approaches aimed to boost the nitrate–nitrite–NO pathway may be of benefit in dialysis patients. The purpose of this study was to examine the kinetics of plasma nitrate and nitrite after a single intake of nitrate-rich concentrated beetroot juice (BJ) in adult hemodialysis (HD) patients and in age-matched healthy volunteers (HV). Eight HD patients and seven HV participated in this single center, randomized, single-blind, placebo-controlled, crossover study. Each participant received a sequential single administration of active BJ (70 mL, 400 mg nitrate) and placebo BJ (70 mL, 0 mg nitrate) in a random order separated by a washout period of seven days. For the kinetic analysis, blood samples were collected at different time-points before and up to 44 h after BJ intake. Compared with placebo, active BJ significantly increased plasma nitrate and nitrite levels both in HD patients and HV. The area under the curve and the maximal concentration of plasma nitrate, but not of nitrite, were significantly higher in HD patients as compared with HV. In both groups, active BJ ingestion did not affect blood pressure or plasma potassium levels. Both BJs were well tolerated in all participants with no adverse events reported. Our data provide useful information in planning dietary nitrate supplementation efficacy studies in patients with reduced NO bioactivity. 相似文献
25.
S. Armeanu I. Haessler R. Saller M. G. Engelmann F. Heinemann E. Krausz J. Stange S. Mitzner B. Salmons W. H. Gunzburg S. Nikol 《Journal of microencapsulation》2013,30(4):491-506
Long-term benefits of coronary angioplasty remain limited by the treatmentinduced renarrowing of arteries, termed restenosis. One of the mechanisms leading to restenosis is the proliferation of smooth muscle cells. Therefore, proliferating cells of the injured arterial wall, which can be selectively transduced by retroviruses, are potential targets for gene therapy strategies. A direct single-dose therapeutic application of retroviral vectors for inhibition of cell proliferation is normally limited by too low transduction efficiencies. Encapsulated retrovirus-producing cells release viral vectors from microcapsules, and may enhance the transduction efficiency by prolonged infection. Primary and immortal murine and porcine cells and murine retrovirusproducing cells were encapsulated in cellulose sulphate. Cell viability was monitored by analysing cell metabolism. Safety, stability, transfer efficiency and extent of restenosis using capsules were determined in a porcine restenosis model for local gene therapy using morphometry, histology, in situ betagalactosidase assay and PCR. Encapsulation of cells did not impair cell viability. Capsules containing retrovirus-producing cells expressing the beta-galactosidase reporter gene were implanted into periarterial tissue or a pig model of restenosis. Three weeks following implantation, beta-galactosidase activity was detected in the pericapsular tissue with a transduction efficiency of ~ 1 in 500 cells. Adventitial implantation of vector-producing encapsulated cells for gene therapy may, therefore, facilitate successful targeting of proliferating vascular smooth muscle cells, and allow stable integration of therapeutic genes into surrounding cells. The encapsulation of vector-producing cells could represent a novel and feasible way to optimize local retroviral gene therapy. 相似文献
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28.
Yap Sing-Chien Anic Ante Breskovic Toni Haas Annika Bhagwandien Rohit E. Jurisic Zrinka Szili-Torok Tamas Luik Armin 《Journal of interventional cardiac electrophysiology》2022,64(3):565-565
Journal of Interventional Cardiac Electrophysiology - 相似文献
29.
Birgit Stürmer Guang Ouyang Changsong Zhou Annika Boldt Werner Sommer 《Psychophysiology》2013,50(1):70-73
When the lateralized readiness potential (LRP) is recorded in stimulus–response compatibility (SRC) tasks, two processes may overlap in the LRP, stimulus‐driven response priming and activation based on response selection rules. These overlapping processes are hard to disentangle with standard analytical tools. Here, we show that Residue Iteration Decomposition (RIDE), based on latency variability, separates the overlapping LRP components from a Simon task into stimulus‐driven and response‐related components. SRC affected LRP amplitudes only in the stimulus‐driven component, whereas LRP onsets were affected only in the response‐locked component. Importantly, the compatibility effect in reaction times was more similar to the effect in the onsets of the RIDE‐derived response‐locked LRP component than in the unseparated LRP. Thus, RIDE‐separated LRP components are devoid of distortions inherent to standard LRPs. 相似文献