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Ultrahigh molecular weight polyethylene (UHMWPE)/nanosilica (F2Sy) and UHMWPE/modified nanosilica (F2Smx‐y) as‐prepared fibers were prepared by spinning of F2Sy and F2Smx‐y gel solutions, respectively. Modified nanosilica particles were prepared by grafting maleic anhydride grafted polyethylenes onto nanosilica particles. The achievable draw ratios (Dra) of F2Sy and F2Smx‐y as‐prepared fibers approached a maximal value as the original and modified nanosilica contents reached corresponding optimum values; the maximal Dra value obtained for F2Smx‐y as‐prepared fiber specimens was significantly higher than that of the F2Sy as‐prepared fiber specimens prepared at the optimum nanosilica content. The melting temperature and evaluated lamellar thickness values of F2Sy and F2Smx‐y as‐prepared fiber series specimens decrease, but crystallinity values increase significantly, as their original and modified nanosilica contents respectively increase. Similar to the achievable drawing properties of the as‐prepared fibers, the orientation factor, tensile strength (σf) and initial modulus (E) values of both drawn F2Sy and F2Smx‐y fiber series specimens with a fixed draw ratio reach a maximal value as the original and/or modified nanosilica contents approach the optimum values; the σf and E values of the drawn F2Smx‐y fiber specimens are significantly higher than those of the corresponding drawn F2Sy fiber specimens prepared at the same draw ratios and nanosilica contents but without being modified. To understand the interesting ultradrawing, thermal, orientation and tensile properties of F2Sy and F2Smx‐y fiber specimens, Fourier transform infrared, specific surface area and transmission electron microscopy analyses of the original and modified nanosilica were performed in this study. © 2012 Society of Chemical Industry

The duodenal switch (DS) procedure is a type of restrictive-malabsorptive bariatric surgery that is typically reserved for severe morbidly obese people (body mass index >50 kg/m(2)) with obesity-related comorbidities, when diet, lifestyle changes, and pharmacologic therapy fail to achieve adequate weight loss. Patients who undergo the DS procedure are at risk for malabsorption, malnutrition, and nutrient deficiencies. Copper deficiency is a commonly reported long-term complication of Roux-en-Y gastric bypass (RYGB) surgery. However, data are limited on copper deficiency-associated complications and their treatment in DS patients. This article presents a case of a patient who developed hypocupremia with associated pancytopenia, myeloneuropathy, and leukoencephalopathy following DS and reviews the literature related to the pathophysiology of copper deficiency and copper replacement in bariatric surgery patients. When severe diarrhea was present, intravenous elemental copper 4 mg (as cupric chloride)/d in addition to daily oral copper gluconate was necessary to correct the hypocupremia and improve the hematologic indices and neurologic symptoms of copper deficiency. When diarrhea subsided, oral elemental copper 4 mg (as copper gluconate) 3 times daily maintained normal serum copper concentrations and avoided the relapse of severe neurologic dysfunction. Regular monitoring of serum copper and ceruloplasmin concentrations is recommended following DS surgery to detect any copper deficiency before irreversible neurologic damage occurs. Long-term copper supplementation is likely necessary to maintain normal copper status in DS patients.

Alcohol use and aging are risk factors for falls requiring immobilization and leading to skeletal muscle atrophy. Skeletal muscle regeneration is integral to post-immobilization recovery. This study aimed to elucidate the effects of alcohol and ovarian hormone loss on the expression of genes implicated in muscle regeneration. Three-month-old female rats received an ovariectomy or a sham surgery, consumed an alcohol-containing or control diet for 10 weeks, were subjected to unilateral hind limb immobilization for seven days, and finally were allowed a three (3d)- or 14 (14d)-day recovery. Immobilization decreased the quadriceps weight at 3d and 14d, and alcohol decreased the quadriceps weight at 14d in the nonimmobilized hind limb (NI). At 3d, alcohol decreased gene expression of myoblast determination protein (MyoD) in the immobilized hind limb (IMM) and myocyte enhancer factor (Mef)2C and tumor necrosis factor (TNF)α in NI, and ovariectomy increased MyoD and decreased TNFα expression in NI. At 14d, alcohol increased the gene expression of Mef2C, MyoD, TNFα, and transforming growth factor (TFG)β in IMM and decreased monocyte chemoattractant protein (MCP)1 expression in NI; ovariectomy increased TNFα expression in NI, and alcohol and ovariectomy together increased Mef2C expression in NI. Despite increased TGFβ expression, there was no concomitant alcohol-mediated increase in collagen in IMM at 14d. Overall, these data indicate that alcohol dysregulated the post-immobilization alteration in the expression of genes implicated in regeneration. Whether alcohol-mediated molecular changes correspond with post-immobilization functional alterations remains to be determined.

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