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The effect of moisture as a function of water activity (Aw) on the compaction process is important to understand particle/water interaction and deformation. Studying powder/moisture interaction under pressure with radial die-wall pressure (RDWP) tool was never done. The aim of our study was to use this tool to study this interaction at high compression pressure and speed. Moreover, the effect of changing ejection cam angle (EA) of the machine on ejection force (EF) was investigated. Also, a new tool for prediction of tablet sticking was proposed. Materials with different deformation behaviors stored at low and high moisture conditions were used. Compaction simulation guided by modeling was applied. High Aw resulted in a low residual die-wall pressure (RDP) for all materials, and a high maximum die-wall pressure (MDP) for plastic materials, p < 0.05. This was due to the lubricating and plasticizing effects of water, respectively. However, microcrystalline cellulose showed capping at high Aw and compaction pressure. By increasing compression pressure at high Aw for all materials, effective fall time (EFT) was increased, p < 0.05, showing tendency for sticking. Increasing EA caused an increase of friction and EF for powders, p < 0.05. RDWP was a useful tool to understand particle/moisture interaction under pressure. 相似文献
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Congenital leptin deficiency is a rare recessive genetic disorder resulting in severe hyperphagia and early onset obesity. It is caused by mutations in the LEP gene encoding leptin. To date, only two mutations have been identified in the LEP gene, Δ133G and R105W. We present the third reported mutation identified in an Egyptian patient with very low serum leptin levels and severe early onset obesity (BMI = 51). Direct sequencing of the coding region of the LEP gene revealed a novel homozygous missense mutation, N103K. The N103K mutation was not found in 100 alleles from 50 unrelated Egyptian normal-weight control subjects using polymerase chain reaction and restriction fragment length polymorphism analysis. In conclusion, this study presents the third reported mutation of the LEP gene and will provide further insight into the physiologic role of leptin in human obesity. 相似文献
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WANG Lei GUO Ji-feng ME Li-luo ZHANG Hai-nan SHEN Lu JIANG Hong PAN Qian XIA Kun TANG Bei-sha YAN Xin-xiang 《中华医学杂志(英文版)》2009,122(24):3082-3085
Parkinson's disease (PD) is the second most common neurodegenerative disorder characterized by a selective loss of nigrostriatal dopaminergic neurons. Clinical manifestations of this complex disease include resting tremor, bradykinesia, postural instability, gait difficulty and rigidity. Approximately 5%-10% of patients have genetic factors, yet etiology of PD remains unclear. Genetic deficits, environmental exposure, oxidative stress, mitochondrial dysfunction, 相似文献
96.
Goldman R Ressom HW Abdel-Hamid M Goldman L Wang A Varghese RS An Y Loffredo CA Drake SK Eissa SA Gouda I Ezzat S Moiseiwitsch FS 《Carcinogenesis》2007,28(10):2149-2153
Hepatocellular carcinoma (HCC) represents an important public health problem in Egypt where up to 90% of HCC cases are attributable to hepatitis C viral (HCV) infection. Serum alpha-fetoprotein is elevated in only approximately 60% of HCC patients. The development of effective markers for the detection of HCC could have an impact on cancer mortality and significant public health implications worldwide. The objective of our study was to assess six candidate markers for detection of HCC identified by mass spectrometric analysis of enriched serum. The study examined 78 HCC cases and 72 age- and gender-matched cancer-free controls recruited from the Egyptian population. Matrix-assisted laser desorption-ionization time-of-flight mass spectrometric analysis of enriched low-molecular weight fraction of serum was used for identification of the candidate markers. Our analyses show that all six candidate markers are associated with HCC after adjustment for important covariates including HCV and hepatitis B viral infections. The marker candidates are independently predictive of HCC with areas under the receiver operating characteristic (AuROC) curve ranging from 63-93%. A combination of the six markers improves prediction accuracy to 100% sensitivity, 91% specificity and 98% AuROC curve in an independent test set of 50 patients. Two of the candidate markers were identified by sequencing as fragments of complement C3 and C4. In conclusion, a set of six peptides distinguished with high prediction accuracy HCC from controls in an Egyptian population with a high rate of chronic HCV infection. Further evaluation of these marker candidates for the diagnosis of HCC is needed. 相似文献
97.
Rui Wang ME Shiyu Yan ME Xue Ma ME Jinfeng Zhao ME Yuqing Han ME Yao Pan PhD Hua Zhao PhD 《Journal of Cosmetic Dermatology》2023,22(12):3427-3435
Background
The semiactive or inactive probiotics or their extracts used in dermatology have interesting properties to ameliorate signs of irritated skin and enhance the skin barrier. Bifidobacterium, as the most common probiotics, which has been found to be effective in reducing acne and improving the skin barrier function of atopic dermatitis. Bifida Ferment Lysate (BFL) can be obtained from Bifidobacterium by fermentation and extraction.Purpose
In this study, we investigated the effect of a topically used BFL on the skin using in vitro evaluation methods.Results
The results showed that upregulation of skin physical barrier gene (FLG, LOR, IVL, TGM1, and AQP3) and antimicrobial peptide gene (CAMP and hBD-2) in HaCaT cells by BFL might be responsible for skin barrier resistance. In addition, BFL had strong antioxidant properties representing a dose-dependent increasing of the scavenging capacity of DPPH, ABTS, hydroxyl, and superoxide radicals. BFL treatment also fundamentally inhibited the intracellular ROS and MDA production and improved the activities of antioxidant enzymes (CAT and GSH-Px) in H2O2-stimulated HaCaT cells. As a good immunomodulatory factor, BFL efficiently decreased the secretion of IL-8 and TNF-α cytokines, and COX-2 mRNA expression in LPS-induced THP-1 macrophages.Conclusion
BFL can strengthen the skin barrier function and stimulate skin barrier resistance, to reinforce the skin against oxidative stress and inflammatory stimuli. 相似文献98.
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Screening of candidate biomaterials for alveolar augmentation using a critical‐size rat calvaria defect model 下载免费PDF全文