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1.
Serum-resistant lipopolyplexes for gene delivery to liver tumour cells.   总被引:1,自引:0,他引:1  
In this study, an efficient non-viral gene transfer system has been developed by employing polyethylenimine (PEI 800, 25 and 22kDa) and DOTAP and cholesterol (Chol) as lipids (lipopolyplex), at three different lipid/DNA molar ratios (2/1, 5/1 and 17/1) by using five different protocols of formulation. Condensation assays revealed that PEI of 800, 25 and 22kDa were very effective in condensing plasmid DNA, leading to a complete condensation at N/P ratios above 4. Addition of DOTAP/Chol liposomes did not further condense DNA. Increasing the molar ratio lipid/DNA in the complex resulted in higher positive values of the zeta-potential, while the particle size increased in some protocols, but not in others. High molecular weight PEI (800kDa) used in the formulation of lipopolyplexes lead to a bigger particle size, compared to that obtained with smaller PEI species, whether branched (25kDa) or linear (22kDa). These vectors were also highly effective in protecting DNA from attack by DNAse I. Transfection activity was maximal by using protocols 3 and 4 and a lipid/DNA molar ratio of 17/1. These complexes showed high efficiency in gene delivery of DNA to liver cancer cells, even in the presence of high concentration of serum (60% FBS). On the other hand, complexes formed with linear PEI (22kDa) were more effective than lipopolyplexes containing branched PEI (800 or 25kDa). The complexes resulted to be much more efficient than conventional lipoplexes (cationic lipid and DNA) and polyplexes (cationic polymer and DNA). The same behaviour was observed for complexes prepared in the presence of the therapeutic gene pCMVIL-12. Toxicity assays revealed a viability higher than 80% in all cases, independently of the protocol, molar ratio (lipid/DNA), molecular weight and type of PEI.  相似文献   
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Psychosocial adjustment to a complex and disabling long-term condition like Parkinson´s disease is a complex, dynamic, cyclical and interactive process. Family caregivers, face multiple challenges that require a significant effort in terms of psychosocial adjustment, which must be considered by healthcare professionals in order to provide a holistic care. The patients’ self-report version of the Psychosocial Adjustment to Illness Scale (PAIS-SR), which has been validated in Spain for use in Parkinson's disease, is designed to evaluate the psychosocial adjustment of patients. Our purpose was to validate the Spanish PAIS-SR version for caregivers of patients with Parkinson's disease. An open, national cross-sectional study with one point-in-time evaluation and retest was carried out in 450 family caregivers of patients with Parkinson's disease. Data were collected in Spain from April 2016 to September 2017. The psychometric analysis performed showed that the Spanish version of the PAIS-SR for caregivers presents adequate indicators of reliability, internal and external validity, and is structured according to the seven-domain model proposed by the author of the instrument.  相似文献   
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Ochratoxin A (OTA), a naturally occurring mycotoxin, is nephrotoxic in all animal species tested and is considered a potent renal carcinogen, particularly in male rats. Its mechanism of toxicity is still unknown, although oxidative stress appears to be a plausible mechanism. Therefore, the objective of this study was to identify the biological pathways that are modulated in vivo by OTA in male F344 rats in order to gain further insight into its mechanism of renal toxicity. Rats were gavaged daily with OTA (500 microg/kg bw) and gene expression profiles in target and non-target organs were analyzed after 7 and 21 days administration. As was expected, a time-dependent increase of OTA concentrations was found in plasma, kidney and liver, with the concentrations found in both tissues being quite similar. However, histopathological examinations only revealed changes in kidney; signs of nephrotoxicity involving single cell necrosis and karyomegalic nuclei were observed in the treated rats. The number of differentially expressed genes in kidney was much higher than in liver (541 versus 11 at both time points). Several similarities were observed with other in vivo gene expression data. However, great differences were found with previous in vitro gene expression data, with the exception of DNA damage response which was not observed at mRNA level in any of our study conditions. Down-regulation was the predominant effect. Oxidative stress response pathway and genes involved in metabolism and transport were inhibited at both time points. RGN (regucalcin) - a gene implicated in calcium homeostasis - was strongly inhibited at both time points and genes implicated in cell survival and proliferation were up-regulated at day 21. Moreover, translation factors and annexin genes were up-regulated at both time points. Apart from oxidative stress, alterations of the calcium homeostasis and cytoskeleton structure may be present at the first events of OTA toxicity.  相似文献   
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Background. Papillary thyroid carcinoma (PTC), follicular thyroid adenoma (FTA), and thyroid nodular hyperplasia (TNH) are the most frequent diseases of the thyroid gland. Previous studies described the involvement of dipeptidyl-peptidase IV (DPPIV/CD26) in the development of thyroid neoplasia and proposed it as an additional tool in the diagnosis/prognosis of these diseases. However, very little is known about the involvement of other peptidases in neoplastic and hyperplastic processes of this gland. Methods. The catalytic activity of 10 peptidases in a series of 30 PTC, 10 FTA, and 14 TNH was measured fluorimetrically in tumour and nontumour adjacent tissues. Results. The activity of DPPIV/CD26 was markedly higher in PTC than in FTA, TNH, and nontumour tissues. Aspartyl aminopeptidase (AspAP), alanyl aminopeptidase (AlaAP), prolyl endopeptidase, pyroglutamyl peptidase I, and aminopeptidase B activities were significantly increased in thyroid neoplasms when compared to nontumour tissues. AspAP and AlaAP activities were also significantly higher in PTC than in FTA and TNH. Conclusions. These data suggest the involvement of DPPIV/CD26 and some cytosolic peptidases in the neoplastic development of PTC and FTA. Further studies will help to define the possible clinical usefulness of AlaAP and AspAP in the diagnosis/prognosis of thyroid neoplasms.  相似文献   
7.

Objectives

The aim of this study is to describe electrocardiographic changes and conduction abnormalities in patients undergoing transcatheter aortic valve implantation (TAVI).

Methods

76 patients who underwent TAVI using Edwards Sapien 3 prosthesis were included, comparing electrocardiographic registries at admission, post-procedure and before discharge.

Results

Patients after TAVI presented a longer PR interval, a wider QRS, and a longer corrected QT, with a left deviation of QRS axis and T waves; reversible changes that tended to correct in the following days after TAVI. Complete atrioventricular block incidence was 2.9%. New-onset left bundle branch block (LBBB) incidence was 39%, although solved in almost half of patients before discharge.

Conclusions

TAVI was associated with different reversible electrocardiographic changes that suggest a transient impact on the conduction system. One of every five patients presented permanent LBBB after valve implant.  相似文献   
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