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81.

Background

β-thymosins play roles in cytoskeleton rearrangement, angiogenesis, fibrosis and reparative process, thus suggesting a possible involvement in the pathogenesis of systemic sclerosis. The aim of the study was to investigate the presence of thymosins β4, β4 sulfoxide, and β10 in bronchoalveolar lavage fluid of scleroderma patients with interstitial lung disease and the relation of these factors with pulmonary functional and radiological parameters.

Methods

β-thymosins concentrations were determined by Reverse Phase-High Performance Liquid Chromatography-Electrospray-Mass Spectrometry in the bronchoalveolar lavage fluid of 46 scleroderma patients with lung involvement and of 15 controls.

Results

Thymosin β4, β4 sulfoxide, and β10 were detectable in bronchoalveolar lavage fluid of patients and controls. Thymosin β4 levels were significantly higher in scleroderma patients than in controls. In addition, analyzing the progression of scleroderma lung disease at one-year follow-up, we have found that higher thymosin β4 levels seem to have a protective role against lung tissue damage. Thymosin β4 sulfoxide levels were higher in the smokers and in the scleroderma patients with alveolitis.

Conclusions

We describe for the first time β-thymosins in bronchoalveolar lavage fluid and their possible involvement in the pathogenesis of scleroderma lung disease. Thymosin β4 seems to have a protective role against lung tissue damage, while its oxidation product mirrors an alveolar inflammatory status.  相似文献   
82.
This review is devoted to the chiral optical behavior of films of racemic polymers whose chirality is induced by cocrystallization with nonracemic (also temporary) guest molecules. We provide examples of macromolecular amplification of chirality, produced by molecular and supramolecular mechanisms, on industrially relevant polymers like poly(2,6‐dimethyl‐1,4‐phenylene)oxide (PPO) and syndiotactic polystyrene (s‐PS). Chirality 28:29–38, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
83.
84.
This study reports on a novel method to detect and reduce the contribution of movement artifact (MA) in electrocardiogram (ECG) recordings gathered from horses in free movement conditions. We propose a model that integrates cardiovascular and movement information to estimate the MA contribution. Specifically, ECG and physical activity are continuously acquired from seven horses through a wearable system. Such a system employs completely integrated textile electrodes to monitor ECG and is also equipped with a triaxial accelerometer for movement monitoring. In the literature, the most used technique to remove movement artifacts, when noise bandwidth overlaps the primary source bandwidth, is the adaptive filter. In this study we propose a new algorithm, hereinafter called Stationary Wavelet Movement Artifact Reduction (SWMAR), where the Stationary Wavelet Transform (SWT) decomposition algorithm is employed to identify and remove movement artifacts from ECG signals in horses. A comparative analysis with the Normalized Least Mean Square Adaptive Filter technique (NLMSAF) is performed as well. Results achieved on seven hours of recordings showed a reduction greater than 40% of MA percentage (between before- and after- the application of the proposed algorithm). Moreover, the comparative analysis with the NLMSAF, applied to the same ECG recordings, showed a greater reduction of MA percentage in favour of SWMAR with a statistical significant difference (pvalue < 0.0.5).  相似文献   
85.
Monocyte chemotactic protein-1 (MCP-1, CCL2) is an important determinant of macrophage infiltration in tumors, ovarian carcinoma in particular. MCP-1 binds the chemokine receptor CCR2. Recent results indicate that proinflammatory and anti-inflammatory signals regulate chemokine receptor expression in monocytes. The present study was designed to investigate the expression of CCR2 in tumor-associated macrophages (TAM) from ovarian cancer patients. TAM isolated from ascitic or solid ovarian carcinoma displayed defective CCR2 mRNA (Northern blot and PCR) and surface expression and did not migrate in response to MCP-1. The defect was selective for CCR2 in that CCR1 and CCR5 were expressed normally in TAM. CCR2 gene expression and chemotactic response to MCP-1 were decreased to a lesser extent in blood monocytes from cancer patients. CCR2 mRNA levels and the chemotactic response to MCP-1 were drastically reduced in fresh monocytes cultured in the presence of tumor ascites from cancer patients. Ab against TNF-alpha restored the CCR2 mRNA level in monocytes cultured in the presence of ascitic fluid. The finding of defective CCR2 expression in TAM, largely dependent on local TNF production, is consistent with previous in vitro data on down-regulation of chemokine receptors by proinflammatory molecules. Receptor inhibition may serve as a mechanism to arrest and retain recruited macrophages and to prevent chemokine scavenging by mononuclear phagocytes at sites of inflammation and tumor growth. In the presence of advanced tumors or chronic inflammation, systemic down-regulation of receptor expression by proinflammatory molecules leaking in the systemic circulation may account for defective chemotaxis and a defective capacity to mount inflammatory responses associated with advanced neoplasia.  相似文献   
86.
Immune-based treatments represent a promising new class of therapy designed to boost the immune system to specifically eradicate malignant cells. Immunotherapy may generate specific anti-tumor immune responses, and dendritic cells (DC), professional antigen-presenting cells, are widely used in experimental cancer immunotherapy. Several reports describe methods for the generation of mature, antigen-pulsed DC for clinical use. Improved quality and standardization are desirable to obtain GMP-compliant protocols. In this study we describe the generation of DC from 31 Glioblastoma (GB) patients starting from their monocytes isolated by immunomagnetic CD14 selection using the CliniMACS® device. Upon differentiation of CD14+ with IL-4 and GM-CSF, DC were induced to maturation with TNF-α, PGE2, IL-1β, and IL-6. Whole tumor lysate was obtained, for the first time, in a closed system using the semi-automated dissociator GentleMACS®. The yield of proteins improved by 130% compared to the manual dissociation method. Interestingly the Mean Fluorescence Intensity for CD83 increased significantly in DC pulsed with “new method” lysate compared to DC pulsed with “classical method” lysate. Our results indicate that immunomagnetic isolation of CD14+ monocytes using the CliniMACS® device and their pulsing with whole tumor lysate proteins is a suitable method for clinical-scale generation of high quality, functional DC under GMP-grade conditions.  相似文献   
87.
Elements with insulator/border activity have been characterized most extensively in Drosophila melanogaster. In vertebrates, the first example of such an element was provided by a hypersensitive site of the chicken beta-globin locus, cHS4. It has been proposed that the homologous site in humans, HS5, functions as a border of the human beta-globin locus. Here, we have characterized HS5 of the human beta-globin locus control region. We have examined its tissue-specificity and assessed its insulating properties in transgenic mice using a lacZ reporter assay. Most importantly, we have tested its enhancer blocking activity in the context of the full beta-globin locus. Our results show that HS5 is erythroid-specific rather than ubiquitous in human tissues. Furthermore, HS5 does not fulfil the criteria of a general in vivo insulator in the transgene protection assay. Finally, a HS5 conditional deletion from the complete locus demonstrates that HS5 has no discernable activity in adult erythroid cells. Surprisingly, HS5 functions as an enhancer blocker in embryonic erythroid cells. We conclude that HS5 is a developmental stage-specific border in erythroid cells.  相似文献   
88.
89.

Background

Seventy percent of urban populations in sub-Saharan Africa live in slums. Sustaining HIV patients in these high-risk and highly mobile settings is a major future challenge. This study seeks to assess program retention and to find determinants for low adherence to antiretroviral treatment (ART) and drop-out from an established HIV/ART program in Kibera, Nairobi, one of Africa''s largest informal urban settlements.

Methods and Findings

A prospective open cohort study of 800 patients was performed at the African Medical Research Foundation (AMREF) clinic in the Kibera slum. Adherence to ART and drop-out from the ART program were independent outcomes. Two different adherence measures were used: (1) “dose adherence” (the proportion of a prescribed dose taken over the past 4 days) and (2) “adherence index” (based on three adherence questions covering dosing, timing and special instructions). Drop-out from the program was calculated based on clinic appointment dates and number of prescribed doses, and a patient was defined as being lost to follow-up if over 90 days had expired since the last prescribed dose. More than one third of patients were non-adherent when all three aspects of adherence – dosing, timing and special instructions – were taken into account. Multivariate logistic regression revealed that not disclosing HIV status, having a low level of education, living below the poverty limit (US$ 2/day) and not having a treatment buddy were significant predictors for non-adherence. Additionally, one quarter of patients dropped out for more than 90 days after the last prescribed ART dose. Not having a treatment buddy was associated with increased risk for drop-out (hazard ratio 1.4, 95% CI = 1.0–1.9).

Conclusion

These findings point to the dilemma of trying to sustain a growing number of people on life-long ART in conditions where prevailing stigma, poverty and food shortages threatens the long-term success of HIV treatment.  相似文献   
90.
Olive is one of the most important tree crops in the Mediterranean region, because of its ability to grow and produce acceptable yields under limited water availability. In this study, the drought tolerance of an olive cultivar Canino was compared to the performance of its derived transgenic line expressing osmotin gene from tobacco, obtained by Agrobacterium-mediated transformation of Canino cultivar. Shoot cultures of both wild-type (wt) and transgenic lines were exposed to drought stress over a 28-day period, and their differential responses to in vitro-drought stress were investigated. After exposure to PEG, most of the shoots from wt plants resulted in damage and exhibited decreased levels of chlorophyll, while those of transgenic line did not show injuries and showed a normal growth even when exposed to the highest PEG concentration (4%). After preliminary evaluation we characterized Canino AT17-1, by measuring several physiological parameters, including the activities of the antioxidant enzymes (POD and CAT), and the content of malondialdehyde (MDA). Both the activity of catalase and the proline content were higher in the leaves of the transgenic shoots compared to wt plants. Consequently, it was observed that the transgenic line accumulated less MDA indicating that the presence of the osmotin gene protected the cell membrane from damage by lipid peroxidation. Together, these results could suggest that the transgenic line Canino AT17-1 was more efficient in the activation of defense responses against oxidative stress with respect to the Canino wt. The further finding that the transgenic shoots also showed higher proline accumulation supported the hypothesis that the osmotin gene conferred to transgenic shoots increased tolerance to drought stress compared with the wt.  相似文献   
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