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991.
C. Ferri D. Giuggioli A. Manfredi N. Quirici C. Scavullo M. Colaci U. Gianelli G. Lambertenghi Deliliers N. Del Papa 《Clinical and experimental dermatology》2010,35(8):885-887
Systemic sclerosis (SSc) is often complicated by severe skin ulcers that are unresponsive to traditional treatments. Vascular alterations are responsible for the ischaemic features of the disease in both the skin and visceral organs. Defective neoangiogenesis correlates with an abnormally reduced quantity of circulating endothelial progenitor cells (EPCs) caused by impaired maturation potential and proliferative capacity of bone-marrow endothelial stem cells. We report a patient with nonhealing cutaneous ulcers successfully treated with recombinant human erythropoietin (rHuEPO). The possible biological effects of this drug were also investigated. Before rHuEPO treatment, the bone-marrow sample contained reduced numbers of EPCs, which were functionally impaired. After a 6-month rHuEPO cycle, a marked increase in endothelial progenitor markers was seen, along with a significant reduction in their apoptotic rates. The clinical and laboratory data variations before and after rHuEPO treatment give new insights into the pathogenetic role of impaired endothelial stem-cell maturation and defective neoangiogenesis in patients with SSc. 相似文献
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993.
PO Nnamani EC Ibezim AA Attama MU Adikwu 《Asian Pacific journal of tropical medicine》2010,3(3):205-210
ObjectiveTo preliminarily investigate three different lipid matrices consisting of two natural homolipids from Capra hircus (goat fat) and Bovine Spp. (tallow fat) and one semi-synthetic lipid (Softisan® 142) separately structured with Phospholipon® 90G (P90G) as potential delivery systems for poorly water soluble drugs.MethodsThe structured lipid matrices were characterized by differential scanning calorimetry (DSC) and employed to prepare solid lipid microparticles (SLMs) by the melt homogenization method using gradient concentrations of polysorbate 80 and at different emulsification times of 2, 5 and 10 min using a Silverson mixer. The SLMs were analyzed for morphology and particle size, thermal properties, stability studies and determination of injectability.ResultsThe results showed that SLM production was optimum at 5 % of lipid matrices, 1.5 % of polysorbate 80 and emulsification time of 5 min. Increase in polysorbate 80 concentrations decreased the particle size of the SLMs. The SLMs were well formed, spherical, smooth and non-porous with particle sizes in the ranges of (13.90 ± 2.10) μm - (0.09 ± 0.01) μm for SLMs produced from the structured - tallow fat; (13.40 ± 1.30) μm - (0.10 ± 0.01) μm for the structured - goat fat and (13.40±2.00) μm - (2.10± 1.00)μm for the structured Softisan® 142 lipid matrices. DSC traces showed that Softisan® 142 was the most crystalline of all three bulk matrices due to its high enthalpy (?7.962 mW/mg) while tallow fat was the least (?5.067 mW/mg) but addition of P90G to the matrices lowered their enthalpies mostly in the structured goat fat matrices. The SLMs when stored at 4-6 ° were most stable and syringeable with 27 G needle.ConclusionsThis suggests that structured goat fat matrices with the enthalpy of ?2.813 mW/mg will mostly favour drug loading of some poorly soluble drugs more than tallow fat (?4.892 mW/mg) and Softisan® 142 (?5.501 mW/mg). 相似文献
994.
KH Gulkesen A Akman YK Yuce E Yilmaz AA Samur F Isleyen DS Cakcak E Alpsoy 《Journal of the European Academy of Dermatology and Venereology》2010,24(8):893-896
Background Some image compression methods are used to reduce the disc space needed for the image to store and transmit the image efficiently. JPEG is the most frequently used algorithm of compression in medical systems. JPEG compression can be performed at various qualities. There are many other compression algorithms; among these, JPEG2000 is an appropriate candidate to be used in future. Objective To investigate perceived image quality of JPEG and JPEG2000 in 1 : 20, 1 : 30, 1 : 40 and 1 : 50 compression rates. Methods In total, photographs of 90 patients were taken in dermatology outpatient clinics. For each patient, a set which is composed of eight compressed images and one uncompressed image has been prepared. Images were shown to dermatologists on two separate 17‐inch LCD monitors at the same time, with one as compressed image and the other as uncompressed image. Each dermatologist evaluated 720 image couples in total and defined whether there existed any difference between two images in terms of quality. If there was a difference, they reported the better one. Among four dermatologists, each evaluated 720 image couples in total. Results Quality rates for JPEG compressions 1 : 20, 1 : 30, 1 : 40 and 1 : 50 were 69%, 35%, 10% and 5% respectively. Quality rates for corresponding JPEG2000 compressions were 77%, 67%, 56% and 53% respectively. Conclusion When JPEG and JPEG2000 algorithms were compared, it was observed that JPEG2000 algorithm was more successful than JPEG for all compression rates. However, loss of image quality is recognizable in some of images in all compression rates. 相似文献
995.
Competence for genetic transformation in Streptococcus pneumoniae and Streptococcus gordonii involves the ComAB secretion apparatus, which is thought to export the competence‐stimulating peptide. Homologous secretory systems are also used for the export of certain bacteriocins and bacteriocin‐like peptides. In this study, a similar secretory apparatus was found in the Streptococcus mutans genome, and its role in transformation was investigated. Gene inactivation resulted in a mutant deficient in transformability. We suggest that secretion of a peptide, possibly the competence‐stimulating peptide itself, is involved in competence induction also in S. mutans. 相似文献
996.
Dragana Nikolic Niki Katsiki Giuseppe Montalto Esma R. Isenovic Dimitri P. Mikhailidis Manfredi Rizzo 《Nutrients》2013,5(3):928-948
Small, dense low density lipoprotein (sdLDL) represents an emerging cardiovascular risk factor, since these particles can be associated with cardiovascular disease (CVD) independently of established risk factors, including plasma lipids. Obese subjects frequently have atherogenic dyslipidaemia, including elevated sdLDL levels, in addition to elevated triglycerides (TG), very low density lipoprotein (VLDL) and apolipoprotein-B, as well as decreased high density lipoprotein cholesterol (HDL-C) levels. Obesity-related co-morbidities, such as metabolic syndrome (MetS) are also characterized by dyslipidaemia. Therefore, agents that favourably modulate LDL subclasses may be of clinical value in these subjects. Statins are the lipid-lowering drug of choice. Also, anti-obesity and lipid lowering drugs other than statins could be useful in these patients. However, the effects of anti-obesity drugs on CVD risk factors remain unclear. We review the clinical significance of sdLDL in being overweight and obesity, as well as the efficacy of anti-obesity drugs on LDL subfractions in these individuals; a short comment on HDL subclasses is also included. Our literature search was based on PubMed and Scopus listings. Further research is required to fully explore both the significance of sdLDL and the efficacy of anti-obesity drugs on LDL subfractions in being overweight, obesity and MetS. Improving the lipoprotein profile in these patients may represent an efficient approach for reducing cardiovascular risk. 相似文献
997.
IMCG Pardo B Geloneze MA Tambascia AA Barros-Filho 《The journal of maternal-fetal & neonatal medicine》2013,26(6):408-410
Objectives: Leptin, a hormone produced in adipose tissue and the placenta, is correlated with neonatal growth. The aim of this study was to investigate the effect of maternal smoking during pregnancy on cord blood leptin concentrations in term, appropriate-for-gestational-age infants.Methods: Two groups of term, appropriate-for-gestational-age newborns were selected: 19 infants of smoking mothers and 91 infants of non-smoking mothers. Neonatal anthropometric measurements were taken and leptin levels were measured by radioimmunoassay.Results: Leptin concentrations were similar (p?=?0.915) between the groups. Leptin levels correlated only with ponderal index (p?<?0.01) and gestational age of the newborns (p?<?0.05).Conclusions: This study indicates that maternal smoking during pregnancy does not affect cord blood leptin levels in term, appropriate-for-gestational-age infants. 相似文献
998.
Alicia K. Matthews Sarah A. Sellergren Clara Manfredi Maryann Williams 《Journal of health communication》2013,18(3):205-219
Qualitative research methods were used to explore factors that may affect medical information seeking, treatment engagement, and emotional adjustment among African American cancer patients. Focus group findings suggest that an array of cultural and socioeconomic factors plays important roles in the behavior of African American cancer patients. Participants described a number of important barriers and facilitators of medical information seeking and treatment participation. Factors linked to the health care-related behaviors and adjustment of African American cancer patients included limited knowledge and misinformation about cancer, mistrust of the medical community, concerns about privacy, lack of insurance, religious beliefs, and emotional issues such as fear and stigma associated with seeking emotional support. Recommendations are made that may assist mental and physical health providers in improving patient information and mental and physical health outcomes of African American cancer patients. 相似文献
999.
1000.