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991.
OBJECTIVE: The objective was to assess the efficacy and safety of erythropoiesis-stimulating proteins (ESPs) in anemia of myelodysplastic syndrome (MDS). METHOD: A systematic review and meta-analysis was conducted covering English-language studies published from 1980 to December 2005. RESULTS: Fifty-nine studies qualified: five controlled trials (n = 354), all epoetin versus control (EvC); 51 epoetin single-arm studies (n = 1,650); and three darbepoetin single-arm studies (n = 102). In the EvC studies, epoetin patients demonstrated a significant advantage over controls in terms of hemoglobin (Hb) response (odds ratio, 5.2; 95% confidence interval, 2.5-10.8). Hb response was 48.1% in single-arm darbepoetin studies, 32.1% in epoetin single-arm studies, and 27.3% in EvC studies. Major Hb response averaged 38.8% in darbepoetin studies, 24.5% in epoetin single-arm studies, and 11.4% in EvC studies. Stratified analyses suggest that lower baseline erythropoietin levels, longer treatment durations, and concurrent iron may be associated with greater Hb response to ESPs. None of the analyzable predictors of Hb response (gender, baseline Hb, ESP type, and ESP duration) were significant in meta-regression analyses. In the few studies with quality-of-life measures, ESP groups attained a pre-post change (Functional Assessment of Cancer Therapy - Fatigue) that exceeded minimum clinically important differences. Selected adverse event rates did not differ between the epoetin and darbepoetin groups. CONCLUSION: Published studies suggest that ESPs are efficacious in anemia of MDS. Hb response appears higher in darbepoetin patients than in epoetin patients, and safety appears comparable, but darbepoetin data are sparse, and there are as yet no direct comparison studies.  相似文献   
992.
Complex musculoskeletal defects resulting from cancer, congenital absence, and trauma represent a unique reconstructive challenge. Autologous tissue is often unavailable to reconstruct these deformities. Composite tissue allograft transplantation represents a unique solution for these clinical problems. Face, hand, or limb transplants can be performed in a single procedure. However, the use of chronic nonspecific systemic immunosuppression can lead to side effects such as drug toxicity, opportunistic infections, and malignancies. This article explores various cell-based therapies that represent promising modalities to reduce chronic immunosuppression and alter the risk/benefit ratios for the prospect of composite tissue allograft transplantation.  相似文献   
993.
In clinical research there is a real possibility to have some conflict of interests. Even for the researcher, the identification of these conflicts cannot be clear. There are many aspects to be considered, involving all participants of the process: the research subject, the researcher, the institution where the research is carried through, the sponsor, the ethics committees, the regulating agencies, the scientific community and the society. The conclusion is that conflicts of interests are common and inevitable in the academic field. The challenge is not to eradicate them, but to recognize them and to manage them properly. The only acceptable way to do this is to expose clearly the conflicts of interests and always to submit the clinical research projects to the ethics committees.  相似文献   
994.
Neuronal nicotinic acetylcholine receptor (nAChR) signaling has been implicated in a variety of normal central nervous system (CNS) functions as well as an array of neuropathologies. Previous studies have demonstrated both neurotoxic and neuroprotective actions of peptides derived from apolipoprotein E (apoE). It has been discovered that apoE-derived peptides inhibit native and recombinant alpha7-containing nAChRs, indicating a direct interaction between apoE peptides and nAChRs. To probe the structure/function interaction between alpha7 nAChRs and the apoE peptide apoE(141-148), experiments were conducted in Xenopus laevis oocytes expressing wild-type and mutated nAChRs. Mutation of Trp55 to alanine blocks apoE peptide-induced inhibition of acetylcholine (ACh)-mediated alpha7 nAChR responses. Additional mutations at Trp55 suggest that hydrophobic interactions between the receptor and apoE(141-148) are essential for inhibition of alpha7 nAChR function. A mutated apoE peptide also demonstrated decreased inhibition at alpha7-W55A nAChRs as well as activity-dependent inhibition of both wild-type alpha7 nAChRs and alpha7-W55A receptors. Finally, a three-dimensional model of the alpha7 nAChR was developed based on the recently refined Torpedo marmorata nACh receptor. A structural model is proposed for the binding of apoE(141-148) to the alpha7 nAChR where the peptide binds at the interface between two subunits, near the ACh binding site. Similar to the functional data, the computational docking suggests the importance of hydrophobic interactions between the alpha7 nAChR and the apoE peptide for inhibition of receptor function. The current data suggest a mode for apoE peptide binding that directly blocks alpha7 nAChR activity and consequently may disrupt nAChR signaling.  相似文献   
995.
996.
This study adapted a U.S. drug use prevention program for use with Russian at-risk adolescents, and explored directions for further development of programs addressing prevention of substance abuse and other health risk behaviors including risk of HIV infection. The adaptation process was conducted in phases, initially carried out in Seattle with 23 bilingual (English-Russian) youth and then further adapted in two Moscow schools with 44 "typical" youth. In the final phase, program adaptation for the Russian at-risk adolescents was achieved by conducting a pilot test of the adapted program lessons with Moscow at-risk adolescents (n=10), who met criteria of poor school performance and/or truancy. Observations and experience were used throughout to adapt and refine the program for at-risk youth. Modifications were made to represent more accurately colloquial Russian and to capture teen experiences common to Russian culture. Both U.S. and Russian youth characterized the lessons as engaging and valuable. They also expressed a need to learn about sexuality, drug use, and health; peer and romantic relationships; and problem-solving strategies.  相似文献   
997.

Aim

This study assessed the impact of dapagliflozin on food intake, eating behaviour, energy expenditure, magnetic resonance imaging (MRI)-determined brain response to food cues and body composition in patients with type 2 diabetes mellitus (T2D).

Materials and Methods

Patients were given dapagliflozin 10 mg once daily in a randomized, double-blind, placebo-controlled trial with short-term (1 week) and long-term (12 weeks) cross-over periods. The primary outcome was the difference in test meal food intake between long-term dapagliflozin and placebo treatment. Secondary outcomes included short-term differences in test meal food intake, short- and long-term differences in appetite and eating rate, energy expenditure and functional MRI brain activity in relation to food images. We determined differences in glycated haemoglobin, weight, liver fat (by 1H magnetic resonance spectroscopy) and subcutaneous/visceral adipose tissue volumes (by MRI).

Results

In total, 52 patients (43% were women) were randomized; with the analysis of 49 patients: median age 58 years, weight 99.1 kg, body mass index 35 kg/m2, glycated haemoglobin 49 mmol/mol. Dapagliflozin reduced glycated haemoglobin by 9.7 mmol/mol [95% confidence interval (CI) 3.91-16.27, p = .004], and body weight (−2.84 vs. −0.87 kg) versus placebo. There was no short- or long-term difference in test meal food intake between dapagliflozin and placebo [mean difference 5.7 g (95% CI −127.9 to 139.3, p = .933); 15.8 g (95% CI −147.7 to 116.1, p = .813), respectively] nor in the rate of eating, energy expenditure, appetite, or brain responses to food cues. Liver fat (median reduction −4.7 vs. 1.95%), but not subcutaneous/visceral adipose tissue, decreased significantly with 12 weeks of dapagliflozin.

Conclusions

The reduction in body weight and liver fat with dapagliflozin was not associated with compensatory adaptations in food intake or energy expenditure.  相似文献   
998.
Lung cancer is the leading cause of cancer death. Pyronaridine, a synthetic drug of artemisinin, has been used in China for over 30 years for the treatment of malaria, but its effect on non-small cell lung cancer (NSCLC) cells is rarely reported. In this study, we determined the efficacy of pyronaridine in four different NSCLC cell lines and explored its mechanism in H1975. The data showed that pyronaridine could upregulate the expression of TNF-related apoptosis-inducing ligand (TRAIL)-mediated death receptor 5 to promote cellular apoptosis. Meanwhile, the JNK (c-Jun N-terminal kinase) level was detected to be significantly increased after treating with pyronaridine. We used JNK inhibitor and found that it could partially inhibit cell apoptosis. The results showed that epidermal growth factor receptor (EGFR), PI3K, and AKT were downregulated after the treatment of pyronaridine. In summary, pyronaridine can selectively kill NSCLC by regulating TRAIL-mediated apoptosis and downregulating the protein level of EGFR. It is a promising anticancer drug for NSCLC.  相似文献   
999.
1000.
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