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1.
Glioblastoma multiforme (GBM) is the most common subtype of primary malignant brain tumor. Although serotype 5 adenoviral vectors (Ads) have been used successfully in clinical trials for GBM, the capacity of Ads to infect human glioma cells and the expression of adenoviral receptors in GBM cells have been challenged. In this report, we studied the expression of three molecules that have been shown to mediate adenoviral entry into cells, i.e., coxsackie and adenovirus receptor (CAR), integrin alphavbeta3 (INT), and major histocompatibility complex class I (MHCI), in rodent glioma cell lines and low-passage primary cultures and cell lines from human GBM. We correlated levels of expression of CAR, INT, and MHCI with transduction efficiency elicited by several high-capacity helper-dependent adenoviral vectors (HC-Ads). Expression levels of adenoviral receptors were variable among the different GBM cells studied. HC-Ad-mediated therapeutic gene expression was efficient, ranging between 20 and 80% of the total target cells expressing the encoded transgenes. Our results show no correlation between the levels of CAR, INT, or MHCI molecules and the levels of transgene expression or the number of GBM cells transduced. We conclude that expression levels of adenoviral receptors do not predict their transduction efficiency or biological function.  相似文献   
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Pituitary tumors are the most common primary intracranial neoplasms. Although most pituitary tumors are considered typically benign, others can cause severe and progressive disease. The principal aims of pituitary tumor treatment are the elimination or reduction of the tumor mass, normalization of hormone secretion and preservation of remaining pituitary function. In spite of major advances in the therapy of pituitary tumors, for some of the most difficult tumors, current therapies that include medical, surgical and radiotherapeutic methods are often unsatisfactory and there is a need to develop new treatment strategies. Gene therapy, which uses nucleic acids as drugs, has emerged as an attractive therapeutic option for the treatment of pituitary tumors that do not respond to classical treatment strategies if the patients become intolerant to the therapy. The development of animal models for pituitary tumors and hormone hypersecretion has proven to be critical for the implementation of novel treatment strategies and gene therapy approaches. Preclinical trials using several gene therapy approaches for the treatment of anterior pituitary diseases have been successfully implemented. Several issues need to be addressed before clinical implementation becomes a reality, including the development of more effective and safer viral vectors, uncovering novel therapeutic targets and development of targeted expression of therapeutic transgenes. With the development of efficient gene delivery vectors allowing long-term transgene expression with minimal toxicity, gene therapy will become one of the most promising approaches for treating pituitary adenomas.  相似文献   
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Aims/background—In humans there are three phosphoglycerate mutase (PGM, EC 5.4.12.1) isoenzymes (MM, MB and BB) which have similar distribution and developmental pathways to creatine kinase (CK, EC 2.7.3.2) isoenzymes. Total serum PGM activity increases in acute myocardial infarction with the same time course as creatine kinase activity. The present study was undertaken to determine changes in the activity of PGM and its isoenzymes after acute myocardial infarction.  相似文献   
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Serum tartrate-resistant acid phosphatase (TRAcP) activity is considered to be a biochemical marker of bone resorption. Recently, a lack of specificity of collagen-related markers for assessing bone turnover has been observed in patients with chronic liver disease. Thus, it could be of great interest to determine serum TRAcP activity in such patients. However, nonspecificity of the analytical reaction could occur when hemolyzed, lipemic, or icteric specimens are analyzed. Therefore, we have studied the interference caused by bilirubin in the measurement of serum TRAcP activity using the Hillmann method. The interference was assessed in two pools of serum containing different bilirubin concentrations but with similar total AcP levels. Mixing proportional parts of the two pools, 10 samples were also obtained. Serum activities of total AcP and TRAcP, and the concentration of bilirubin were measured in the 10 samples. Both the actual and the expected values obtained by theoretical calculations were compared. Serum bilirubin values of 2.4 mg/dl showed a negative interference of 15% in the determination of serum TRAcP activity, whereas values of bilirubin higher than 10 mg/dl interfered totally with the measurement of serum TRAcP. Bilirubin did not interfere with the total AcP determination. This study clearly shows the interference of bilirubin in the determination of serum TRAcP. This finding should be considered when bone metabolism disorders are evaluated in jaundiced patients. Received: 6 April 1998 / Accepted: 1 October 1998  相似文献   
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Pharmaceutical Research - 3D printing (3DP) makes it possible to obtain systems that are not achievable with current conventional methods, one of them, sustained release floating systems. Floating...  相似文献   
7.
Genotoxic effects of therapeutic ultrasound are poorly documented, when compared with the wide use of this physical agent. The aim of this work was to investigate the clastogenic and aneugenic potential of 1 MHz ultrasound, employing intensities (200 and 300 mW/cm2) above the cavitational threshold, but in the range of those normally used in therapeutics. Both normal fibroblasts (AG01522) and tumoral cells (MCF‐7) were sonicated. While no effects on viability were noted, significant increases of CREST‐negative micronuclei (indicative of clastogenesis) and CREST‐positive micronuclei (indicative of aneuploidy) were detected. Clastogenesis was confirmed by increases of γ‐H2AX foci, while increases of spindle anomalies confirmed the induction of aneuploidy. Our results confirm previous works that showed ultrasound‐induced DNA breakage. Moreover, our experiments show that the known effect of ultrasound‐induced damage to microtubules is also able to damage the mitotic spindle and induce aneuploidy. On the overall, this work highlights the importance to further investigate the potential risks related to therapeutics US. Environ. Mol. Mutagen. 59:60–68, 2018. © 2017 Wiley Periodicals, Inc.  相似文献   
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Objectives  To evaluate treatment-seeking behaviour, financial impact and time lost due to malaria events, in southern Mozambique and eastern South Africa.
Methods  In-depth household surveys (828 in Mozambique and 827 in South Africa) were analysed. An asset index was calculated using principal component analysis to allow comparison across socio-economic groups. Direct costs of seeking care and the time lost due to malaria were determined. The extent of catastrophic payments was assessed using as thresholds the traditional 10% of household income and 40% of non-food income, as recently recommended by WHO.
Results  Poverty was highly prevalent: 70% of the South African and 95% of Mozambican households studied lived on less than $1 per capita per day. Around 97% of those with recent malaria sought healthcare, mainly in public facilities. Out-of-pocket household expenditure per malaria episode averaged $2.30 in South Africa and $6.50 in Mozambique. Analysis at the individual household level found that 32–34% of households in Mozambique, compared with 9–13% of households in South Africa, incurred catastrophic payments for malaria episodes. Results based on mean values underestimated the prevalence of catastrophic payments. Days off work/school were higher in Mozambique.
Conclusions  The high rate of health seeking in public health facilities seems unusual in the African context, which bodes well for high coverage with artemisinin-based combinations, even if only deployed within the public sector. However, despite no or modest charges for public sector primary healthcare, households frequently incur catastrophic expenditure on a single malaria episode.  相似文献   
10.
Virus Genes - Argentina exhibits low serological prevalence for Hepatitis B virus (HBV); however, occult hepatitis B infection (OBI) has been reported in blood donors, Amerindians and individuals...  相似文献   
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