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991.
Poly(lactic-co-glycolic acid) (PLGA) microparticles are used in various disorders for the controlled or sustained release of drugs, with the management of salivary gland pathologies possible using this technology. There is no record of the response to such microparticles in the glandular parenchyma. The purpose of this study was to assess the morphological changes in the parotid gland when injected with a single dose of PLGA microparticles. We used 12 adult female Sprague Dawley rats (Rattus norvegicus) that were injected into their right parotid gland with sterile vehicle solution (G1, n=4), 0.5 mg PLGA microparticles (G2, n=4), and 0.75 mg PLGA microparticles (G3, n=4); the microparticles were dissolved in a sterile vehicle solution. The intercalar and striated ducts lumen, the thickness of the acini and the histology aspect in terms of the parenchyma organization, cell morphology of acini and duct system, the presence of polymeric residues, and inflammatory response were determined at 14 days post-injection. The administration of the compound in a single dose modified some of the morphometric parameters of parenchyma (intercalar duct lumen and thickness of the glandular acini) but did not induce tissue inflammatory response, despite the visible presence of polymer waste. This suggests that PLGA microparticles are biocompatible with the parotid tissue, making it possible to use intraglandular controlled drug administration.  相似文献   
992.
Risperidone is a potent antagonist of both dopamine and serotonin receptors. However, little is known about the underlying molecular mechanism by which risperidone acts. Although a number of genetic variants have been observed to correlate with treatment response there are no definitive predictors of response. We performed a genome-wide gene expression analysis (Human Genome U219 Array Plate) of a human neuroblastoma cell line (SK-N-SH) exposed to risperidone to identify molecular mechanisms involved in the cellular response to risperidone and thus identify candidate genes for pharmacogenetic studies. Our results revealed that cellular risperidone treatment is associated with a range of gene expression changes, which are time (6–48 h) and dose related (0.1–10 μM). We found that functional clusters of these changes correspond to Gene Ontology categories related to neural cell development functions, and synaptic structure and functions. We also identified Canonical Pathways related to these functional categories: neurogenesis and axon guidance; synaptic vesicle; and neurotransmitter signaling (dopamine, serotonin and glutamate). Finally, we identified candidate genes for pharmacogenetic studies related to the main risperidone secondary effects: motor disorders, cardiovascular disorders and metabolic disorders. Our results suggest that risperidone treatment affects the neurogenesis and neurotransmission of neuroblastoma cells, which is in agreement with the “initiation and adaptation” model to explain the mechanism of action of psychotropic drugs.  相似文献   
993.
Few studies have been conducted on the effects of air pollution on patients with chronic obstructive pulmonary disease (COPD). During a 14-mo period, 39 Parisian adults with severe COPD were monitored by their physicians. Daily levels of 4 air pollutants were provided by an urban air-quality network. Exacerbation of COPD was associated only with ozone (O3) (odds ratio [OR] = 1.44 for a 10-μg/m3 increase in O3; 95% confidence interval [Cl] = 1.14, 1.82), with a lag of 2-3 days. The effect of O3 was greater in patients whose carbon dioxide pressure (PaCO2) was higher than 43 mm Hg (OR = 1.83; 95% Cl = 1.36, 2.47) vs. those with a lower PaCO2 (OR = 1.26; 95% Cl = 0.90, 1.77). The effect of O3 was unchanged, regardless of the maintenance medications used. The only air pollutant to which patients with severe COPD were particularly sensitive was O3.  相似文献   
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BackgroundThe cost-effectiveness of the 70-gene signature (70-GS) (MammaPrint®) has earlier been estimated using retrospective validation data. Based on the prospective 5-year survival data of the microarRAy-prognoSTics-in-breast-cancER (RASTER) study, the aim here was to evaluate the cost-effectiveness reflecting the actual use in clinical practice, including reality-based compliance rates.MethodsCosts and outcomes (quality-adjusted-life-years (QALYs)) were calculated in node-negative (N?) patients included in the RASTER study (n = 427). Sensitivity and specificity of the 70-gene and Adjuvant! Online (AO) were based on 5-year distant-disease-free survival (DDFS). Subgroup analyses were performed for two groups for whom benefit of the 70-gene had earlier been reported: (1) ductal, oestrogen receptor-positive (ER+), tumour diameter 10–30 mm, grade II, age 40–70; (2) ductal, oestrogen receptor-positive, tumour diameter 5–30 mm, grade II/III and age 40–70.ResultsBased on 5-year survival data, the cost-effectiveness of the 70-gene signature versus AO was prospectively confirmed. The total health care costs per patient were €26,786 for the 70-gene and €29,187 for AO. The quality adjusted life years yielded 12.49 and 11.88, respectively. The subgroups retrieved slightly higher life gains and higher costs, but all resulted finally in a favourable position for the 70-gene signature.ConclusionsThe use of the 70-gene signature, as judged appropriate by doctors and patients and supported by a low risk 70-gene signature as an oncological safe choice, was also found to be cost-effective.  相似文献   
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Although vincristine (VCR) is sometimes prescribed for newly diagnosed immune thrombocytopenia (ITP), its efficacy in refractory ITP and sustained efficacy has yet to be demonstrated. We describe our clinical experience and recommend vincristine's correct place in ITP management. This retrospective study analysed data from 35 patients with newly diagnosed (ND), persistent (P) or chronic (C) ITP treated with VCR. The initial response rate, defined as >30 × 109 platelets/L, reached 86% after a median of 7 [interquartile range (IQR) 6–13] days. In ND and P ITP, even when previous therapies were inefficient, initial response was 87.5%, suggesting that this treatment could be used particularly in rescue. Median survival time, without failure or relapse, was 15 months (Kaplan–Meier curve). Predictive factors (univariate analysis) of an initial and long‐term response were a small number of prior treatments received. However, at 2 yr, only seven patients had sustained response. Eight (23%) patients experienced adverse events: neuropathy for seven and bowel obstruction for one. Vincristine efficacy in ITP was confirmed, and it could be a good strategy for treating resistant ITP, especially in emergencies. In this era of new therapeutics, VCR deserves to remain on the list of ITP treatments because of its initial efficacy, safety and low cost.  相似文献   
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