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BackgroundFloating elbow injuries are complex injuries. Due to frequent association with severe soft tissue injuries and polytrauma, they have unpredictable functional outcome. This prospective study is aimed to evaluate the factors affecting functional outcome.MethodsThirty patients with floating elbow injuries were treated at a level 1 trauma center from July 2018 to June 2019 with minimum follow-up of 9 months. The outcome was assessed by disability for arm shoulder and hand score (DASH) and mayo elbow performance score (MEPS).ResultsThe overall incidence was 16.09 per 1000, mostly caused by road traffic accidents and all cases were managed surgically. Age, gender, education, occupation, arm dominance, and mechanism of injury did not significantly affect the outcomes. Open fractures and patients requiring staged procedure were associated with poorer outcomes (p < 0.05); however, delay in surgery for more than 24 h significantly increased the rate of complications. There was no statistical difference in the proportion of patients who had nerve injury pre operatively and post operatively on the final outcome.ConclusionFloating elbow injuries are relatively rare but nowadays the numbers are on the rise. Timely intervention with a multimodal approach and well-supervised rehabilitation can assure better final outcome.  相似文献   
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The antimicrobial nature of Antharaea mylitta silk-fibroin (SF) is reported but antioxidant potential and the immunomodulatory role towards the fibroblast cell repair process is not explored. Polyurethane is reported to have inflammatory potential by mononuclear cells directed cytokine release, which can guide fibroblast repair. Present study demonstrates the conjunctive effect of inflammatory PU/SF to regulate the favorable shift from pro-inflammatory to anti-inflammatory cytokine stimulation for accelerated fibroblast repair. Minimal inhibitory concentration of SF was determined against pathogenic strains and the effect of SF was investigated for fibroblast NIH3T3 cell adhesion. SF doses (8, 8.5, 9 mg mL−1) were found to be greater than both the IC50 of DPPH scavenging and the ED50 for NIH3T3 proliferation. Anti-lipid peroxidase (ALP) activity of SF doses and citric acid-treated NIH3T3 cells were compared under hydrogen peroxide (H2O2) induced oxidative stress. 9 mg mL−1 SF showed greater ALP activity than the citric acid standard. SF-driven protection to oxidative damage was measured by viable cell fraction in trypan blue dye exclusion assay where 9 mg mL−1 SF showed the highest viability (p ≤ 0.05). 9 mg mL−1 SF was blended with PU for scaffold (w/v = 2 : 5, 2 : 7, 2 : 9) fabrication. The protective effect of PU/SF (2 : 5, 2 : 7, 2 : 9) against oxidative stress was verified by damaged cell survival in MTT assay and DNA quantification. The highest number of cells survived on PU/SF (2 : 9) at all intervals (p ≤ 0.01) upon oxidative damage; PU/SF (2 : 9) was also fabricated by employing the immobilization technique. Immobilized PU/SF (2 : 9) exhibited a greater zone of microbial inhibition, a higher extent of inhibition to microbial adherence, and caused more LDH release from bacterial cell membrane due to membrane rupture, resulting in bacterial cell death (E. coli, K. pneumoniae, P. aeruginosa, S. aureus) compared to the experimental results shown by blended PU/SF (2 : 9). The protective nature of PU/SF (2 : 9) against oxidative stress was ensured through the LDH activity of damaged NIH3T3 cells. Initial raised IL-6, TNF-alpha (pro-inflammatory cytokines) and lowered IL-8, IL-10 (anti-inflammatory cytokine) profiles coupled with fallen IL-6, TNF-alpha, and elevated IL-8, IL-10 at later hours synergistically progress the inflammatory phase of in vitro scratch wound repair in mononuclear culture treated by PU/SF (2 : 9).

Initially SF accelerated pro-inflammatory cytokines, restricted anti-inflammatory cytokines; later it regulated in reverse order. SF potentially eradicated ROS and promoted Ki-67 cellular regeneration whereas pristine PU could not.  相似文献   
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Neurotoxicity Research - Cerebral ischemia-reperfusion (C I/R) accelerates neuronal injury through the overproduction of reactive oxygen species due to mitochondrial dysfunction. Hesperidin has...  相似文献   
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The SARS-CoV-2 Delta variant is emerging as a globally dominant strain. Its rapid spread and high infection rate are attributed to a mutation in the spike protein of SARS-CoV-2 allowing for the virus to invade human cells much faster and with an increased efficiency. In particular, an especially dangerous mutation P681R close to the furin cleavage site has been identified as responsible for increasing the infection rate. Together with the earlier reported mutation D614G in the same domain, it offers an excellent instance to investigate the nature of mutations and how they affect the interatomic interactions in the spike protein. Here, using ultra large-scale ab initio computational modeling, we study the P681R and D614G mutations in the SD2-FP domain, including the effect of double mutation, and compare the results with the wild type. We have recently developed a method of calculating the amino-acid–amino-acid bond pairs (AABP) to quantitatively characterize the details of the interatomic interactions, enabling us to explain the nature of mutation at the atomic resolution. Our most significant finding is that the mutations reduce the AABP value, implying a reduced bonding cohesion between interacting residues and increasing the flexibility of these amino acids to cause the damage. The possibility of using this unique mutation quantifiers in a machine learning protocol could lead to the prediction of emerging mutations.  相似文献   
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Quantitative in vivo oximetry has been reported using 19F MRI in conjunction with reporter molecules, such as perfluorocarbons, for tissue oxygenation (pO2). Recently, hexamethyldisiloxane (HMDSO) has been proposed as a promising alternative reporter molecule for 1H MRI‐based measurement of pO2. To aid biocompatibility for potential systemic administration, we prepared various nanoemulsion formulations using a wide range of HMDSO volume fractions and HMDSO to surfactant ratios. Calibration curves (R1 versus pO2) for all emulsion formulations were found to be linear and similar to neat HMDSO for low surfactant concentrations (< 10% v/v). A small temperature dependence in the calibration curves was observed, similar to previous reports on neat HMDSO, and was characterized to be approximately 1 Torr/ °C under hypoxic conditions. To demonstrate application in vivo, 100 µL of this nanoemulsion was administered to healthy rat thigh muscle (Fisher 344, n = 6). Dynamic changes in mean thigh tissue pO2 were measured using the PISTOL (proton imaging of siloxanes to map tissue oxygenation levels) technique in response to oxygen challenge. Changing the inhaled gas to oxygen for 30 min increased the mean pO2 significantly (p < 0.001) from 39 ± 7 to 275 ± 27 Torr. When the breathing gas was switched back to air, the tissue pO2 decreased to a mean value of 45 ± 6 Torr, not significantly different from baseline (p > 0.05), in 25 min. A first‐order exponential fit to this part of the pO2 data (i.e. after oxygen challenge) yielded an oxygen consumption‐related kinetic parameter k = 0.21 ± 0.04 min?1. These results demonstrate the feasibility of using HMDSO nanoemulsions as nanoprobes of pO2 and their utility to assess oxygen dynamics in vivo, further developing quantitative 1H MRI oximetry. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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Three patients of delayed extradural hematoma (EDH) were seen in the last one year among forty eight consecutively treated cases of EDH. All the three hematomas were evacuated. Awareness of this entity and a high degree of vigilance are strongly recommended to detect such cases. Repeat CT should always be done, especially after decompression by either surgical or medical means, recovery from shock or whenever there is evidence of even minimal bleeding under a skull fracture on initial CT scan.  相似文献   
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