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51.
Mixed cultures of mouse fibroblasts and mouse fibroblasts transformed with Kirsten murine sarcoma virus were grown in petri dishes and overlayed with casein. The appearance of focal lysis zones required the presence of transformed cells in the culture and plasminogen in the overlay, indicating that caseinolysis was due to plasminogen activator released by the malignant cells. Caseinolysis was inhibited by addition of human plasma or bovine pancreatic trypsin inhibitor to the overlay, 1 ml of plasma being equivalent to 67 ± 18 (mean ± S.E.) kallikrein inhibitor (KI) units of trypsin inhibitor.The culture fluid of a human melanoma line induced lysis of a fibrin clot, 1 ml of culture fluid being equivalent to 250 CTA units of urokinase (EC 3.4.99.26). Fibrinolysis was inhibited by addition of human plasma or trypsin inhibitor, 1 ml of plasma being equivalent to 94 ± 34 KI units of trypsin inhibitor.Specific removal of antiplasmin, the fast-reacting plasmin inhibitor (Collen, D. (1976) Eur. J. Biochem. 69, 209), from plasma by immunoabsorption completely abolished its inhibitory activity, both in the caseinolytic and fibrinolytic assays. It is therefore concluded that antiplasmin is the only protein in human plasma capable of inhibiting the fibrinolytic activity associated with oncogenic transformation or neoplasia. Whether this effect is exclusively due to inhibition of formed plasmin or also to interference with plasminogen activvtion remains unsettled.  相似文献   
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The cultivated sunflower (Helianthus annuus L.) is one of the most important oil crops in the world. The importance of sunflower oil in human nutrition and in the chemical industry makes the sunflower a major research interest. An essential element for genomic libraries is the preparation of high molecular weight (HMW) DNA. We developed 2 methods for isolating HMW sunflower DNA. We prepared the DNA from nuclei and from protoplasts isolated from mesophyll tissue with the enzymes cellulase RS and pectolyase Y23. The HMW DNA was digested with restriction endonucleases. The ethidium bromide-stained gel suggested the DNA to be completely digested. These results were confirmed by Southern analysis using a radiolabeled RFLP marker. Both methods made it possible to generate sufficient quantities of megabase-size sunflower DNA suitable for bacterial artificial chromosome (BAC) cloning.  相似文献   
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Background

Lung protective mechanical ventilation (MV) is the corner stone of therapy for ARDS. However, its use may be limited by respiratory acidosis.This study explored feasibility of, effectiveness and safety of low flow extracorporeal CO2 removal (ECCO2R).

Methods

This was a prospective pilot study, using the Abylcap® (Bellco) ECCO2R, with crossover off-on-off design (2-h blocks) under stable MV settings, and follow up till end of ECCO2R. Primary endpoint for effectiveness was a 20% reduction of PaCO2 after the first 2-h. Adverse events (AE) were recorded prospectively.We included 10 ARDS patients on MV, with PaO2/FiO2?<?150 mmHg, tidal volume?≤?8 mL/kg with positive end-expiratory pressure ≥?5 cmH2O, FiO2 titrated to SaO2 88–95%, plateau pressure ≥?28 cmH2O, and respiratory acidosis (pH <7.25).

Results

After 2-h of ECCO2R, 6 patients had a ≥?20% decrease in PaCO2 (60%); PaCO2 decreased 28.4% (from 58.4 to 48.7 mmHg, p?=?0.005), and pH increased (1.59%, p?=?0.005). ECCO2R was hemodynamically well tolerated. During the whole period of ECCO2R, 6 patients had an AE (60%); bleeding occurred in 5 patients (50%) and circuit thrombosis in 3 patients (30%), these were judged not to be life threatening.

Conclusions

In ARDS patients, low flow ECCO2R significantly reduced PaCO2 after 2 h, Follow up during the entire ECCO2R period revealed a high incidence of bleeding and circuit thrombosis.

Trial registration

https://clinicaltrials.gov identifier: NCT01911533, registered 23 July 2013.
  相似文献   
54.
Functional & Integrative Genomics - Congenital diaphragmatic hernia (CDH) is an anomaly characterized by a defect in the diaphragm, leading to the passage of intra-abdominal organs into the...  相似文献   
55.
The present study was performed to produce the protease using free and immobilized cells of locally isolated cold-adapted psychrotolerant yeast Cryptococcus victoriae CA-8. Cell immobilization was performed using sodium alginate as entrapping agent. The best conditions for enzyme production by both free and immobilized cells of the yeast were temperature of 15°C and initial pH of 8.0. The optimal incubation times were 72 and 96 h for immobilized and free cells, respectively. Immobilized cells were reused in 3 successive reaction cycles without any loss in the maximum protease activity. Little decreases in the protease activity were observed in 4 and 5 cycles. Under the optimized conditions, the maximum enzyme activities were determined as 12.1 and 13.5 U/mL for free and immobilized cells, respectively. This is a first attempt on cold-active alkaline protease production by free and/or immobilized cells of yeasts. Besides, the protease activity of the yeast C. victoriae CA-8 was investigated for the first time in the present study.  相似文献   
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Ischemia-reperfusion-induced (I/R) renal damage is a pathogenic process that starts with ischemia, then progresses through oxidative stress and inflammation. Tocilizumab (TCZ), a recombinant human monoclonal antibody produced against the IL-6 receptor, will be tested against renal I/R injury. TCZ is known to lower the levels of proinflammatory cytokines and oxidant mediators while raising the amounts of antioxidant molecules. Our purpose is to evaluate the biochemical and histological effects of TCZ against I/R-induced oxido-inflammatory kidney damage and dysfunction in rats. Animals were divided into 3 groups as renal I/R (RIR), I/R+ TCZ (IRT), and healthy group (HG). TCZ was administered at a dose of 8 mg/kg to the IRT group (n=6) of the animals, and distilled water as a solvent was administered intraperitoneally (ip) to the RIR (n=6) and HG (n=6) groups. Then, two hours of ischemia and six hours of reperfusion were applied to the left kidneys of IRT and RIR animals. TCZ significantly inhibited the increase in the levels of malondialdehyde (MDA), nuclear kappa B (NF-κB), tumour necrosis factor alpha (TNF-α), interleukin 1-β (IL-1β), IL-6, creatinine (Cr) and blood urea nitrogen (BUN) and decrease in total glutathione (tGSH) with I/R in renal tissue. TCZ also attenuated severe histopathological damage due to I/R in renal tissue. TCZ protected renal tissue from I/R-induced oxidative and inflammatory damage. These results indicate that TCZ may be useful in the treatment of renal I/R injury.  相似文献   
58.
Osteoporosis-pseudoglioma syndrome (OPS) is an autosomal recessive disorder characterized by severe juvenile-onset osteoporosis and congenital or juvenile-onset blindness. The pathogenic mechanism is not known. Clinical, biochemical, and microscopic analyses suggest that OPS may be a disorder of matrix homeostasis rather than a disorder of matrix structure. Consequently, identification of the OPS gene and its protein product could provide insights regarding common osteoporotic conditions, such as postmenopausal and senile osteoporosis. As a first step toward determining the cause of OPS, we utilized a combination of traditional linkage analysis and homozygosity mapping to assign the OPS locus to chromosome region 11q12-13. Mapping was accomplished by analyzing 16 DNA samples (seven affected individuals) from three different consanguineous kindreds. Studies in 10 additional families narrowed the candidate region, supported locus homogeneity, and did not detect founder effects. The OPS locus maps to a 13-cM interval between D11S1298 and D11S971 and most likely lies in a 3-cM region between GSTP1 and D11S1296. At present, no strong candidate genes colocalize with OPS.  相似文献   
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