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Fate of micelles and quantum dots in cells.   总被引:2,自引:0,他引:2  
Micelles and quantum dots have been used as experimental drug delivery systems and imaging tools both in vitro and in vivo. Investigations of their fate at the subcellular level require different surface-core modifications. Among the most common modifications are those with fluorescent probes, dense-core metals or radionucleids. Cellular fate of several fluorescent probes incorporated into poly(caprolactone)-b-copolymer micelles (PCL-b-PEO) was followed by confocal microscopy, and colloidal gold incorporated in poly 4-vinyl pyridine-PEO micelles were developed to explore micelle fate by electron microscopy. More recently, we have examined quantum dots (QDs) as the next-generation-labels for cells and nanoparticulate drug carriers amenable both to confocal and electron microscopic analyses. Effects of QDs at the cellular and subcellular levels and their integrity were studied. Results from different studies suggest that size, charge and surface manipulations of QDs may play a role in their subcellular distribution. Examples of pharmacological agents incorporated into block copolymer micelles, administered or attached to QD surfaces show how the final biological outcome (e.g. cell death, proliferation or differentiation) depends on physical properties of these nanoparticles.  相似文献   
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A case of an unusual lesion from the maxilla is presented. Macroscopically, the lesion was solid and histologically consisted of 'multiple separate keratocysts' of varying size that infiltrated into the surrounding bone and soft tissues. Panoramic image and CT scans showed a multilocular honeycomb ill-defined radiolucency with infiltration into the maxillary sinus and floor of orbit. This lesion should be differentiated from similar odontogenic lesions, such as keratoameloblastoma and papilliferous keratoameloblastoma. As there was no evidence of follicles, islands of ameloblastoma, or papilliferous structures in the entire specimen, the lesion could not be diagnosed as either a keratoameloblastoma or a papilliferous keratoameloblastoma. The invasive and destructive growth behavior, the histopathological features, and the histochemical pattern of the collagen stroma imply that this solid lesion is a neoplasia. It is suggested that the proper term for this lesion is solid variant of odontogenic keratocyst.  相似文献   
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There has been a large amount of work done recently on small peripheral stage I adenocarcinomas that come to resection. Radiological (including proportion of ground glass opacity) and pathological features of these lesions (predominant bronchioloalveolar component, central scar with or without invasion <0.5 cm) have been shown to be prognostically favorable with cure rate approaching 100% in some series. Most of these studies emanate from Japan. The relevance of these studies to other parts of the world, particularly North America, is discussed in light of the fact that some recent chemotherapeutic studies with gefitinib have shown increased response in individuals of Asian origin, suggesting that some genetic differences may be significant. The relevance of these findings to pathologists and the pathological study of small peripheral adenocarcinomas from elsewhere in the world are discussed.  相似文献   
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Purpose: There is a common opinion that spinal fractures usually reflect the substantial impact of injuries and therefore may be used as a marker of significant associated injuries, specifically for intraabdominal injury (IAI). The impact of concomitant spinal cord injury (SCI) with the risk of associated IAI has not been well clarified. The aim of this study was to evaluate the incidence and severity of IAIs in patients suffering from spinal fractures with or without SCI. Methods: A retrospective cohort study using the Israeli National Trauma Registry was conducted. Patients with thoracic, lumbar and thoracolumbar fractures resulting from blunt mechanisms of injury from January 1, 1997 to December 31, 2018 were examined, comparing the incidence, severity and mortality of IAIs in patients with or without SCI. The collected variables included age, gender, mechanism of injury, incidence and severity of the concomitant IAIs and pelvic fractures, abbreviated injury scale, injury severity score, and mortality. Statistical analysis was performed using GraphPad InStat ® Version 3.10, with Chi-square test for independence and two sided Fisher’s exact probability test. Results: Review of the Israeli National Trauma Database revealed a total of 16,878 patients with spinal fractures. Combined thoracic and lumbar fractures were observed in 1272 patients (7.5%), isolated thoracic fractures in 4967 patients (29.4%) and isolated lumbar fractures in 10,639 patients (63.0%). The incidence of concomitant SCI was found in 4.95% (63/1272), 7.65% (380/4967) and 2.50% (266/10639) of these patients, respectively. The overall mortality was 2.5%, proving higher among isolated thoracic fracture patient than among isolated lumbar fracture counterparts (11.3% vs. 4.6%, p < 0.001). Isolated thoracic fractures with SCI were significantly more likely to die than non-SCI counterparts (8.2% vs. 3.1%, p < 0.001). There were no differences in the incidence of IAIs between patients with or without SCI following thoracolumbar fractures overall or in isolated thoracic fractures; although isolated lumbar fractures patients with SCI were more likely to have renal (3.4% vs. 1.6%, p = 0.02) or bowel injuries (2.3% vs. 1.0%, p = 0.04) than the non-SCI counterparts. Conclusion: SCI in the setting of thoracolumbar fracture does not appear to be a marker for associated IAI. However, in a subset of isolated lumbar fractures, SCI patient is associated with increased risks for renal and bowel injury.  相似文献   
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BackgroundBody contouring in the postbariatric surgery patient improves quality of life and daily function.ObjectivesTo determine the risk profile of panniculectomy when performed in select patients at the time of bariatric surgery.SettingMetabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) participating centers.MethodsWe examined the MBSAQIP database (2016-2017), in which data on 379,544 bariatric surgeries are reported. Concurrent panniculectomy procedures were identified by Current Procedural Technology (CPT) codes. Patient characteristics and in-hospital as well as 30-day complications were compared between the body contouring group and propensity score-matched bariatric surgery controls.ResultsOne hundred twenty-four patients met inclusion criteria and were matched to 248 controls. An infra-umbilical panniculectomy was performed in the majority of patients (n = 94, 75.8%). Most patients received an open rather than laparoscopic bariatric surgery (n = 87, 70.2%). There were no statistically significant differences between 30-day mortality (1.9%), wound complications (11.5%), readmission (12.5%) and reoperation (5.8%) between the 2 groups (P > .05). Wound complications occurred in 11.5% of patients and were associated with prolonged hospital stay (odds ratio 4.65, 95% confidence interval 1.99–10.86, P < .001) and a body mass index (BMI) > 50 (odds ratio 3.19, 95% confidence interval 1.02–9.96, P = .046).ConclusionIn select patients, panniculectomy at the time of bariatric surgery was not associated with increased in-hospital or 30-day adverse outcomes compared with matched bariatric surgery controls. This procedure may be performed in select patients, with awareness that revision surgery may be needed once weight loss stabilizes.  相似文献   
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Wound‐dressing performances are affected by exudate viscosity, resistance to flow because of gravity, and bodyweight loads, the level of which is related to the body position. Here, we focussed on two dressing properties: (a) Sorptivity—the ability of dressings to transfer exudate away from the wound bed by capillary action—and (b) Durability—the capacity of dressings to maintain their integrity over time and during their removal. Both properties are critically important for avoiding further tissue damage but require the development of new laboratory tests for their measurement. A computer‐controlled phantom of an exuding sacral pressure ulcer has therefore been developed and used to compare the performances of Exufiber (Mölnlycke Health Care) vs an alternative market‐leading dressing. Sorptivity was determined using weight tests, and durability was measured through tensile tests of the used dressings. For a supine configuration, the Exufiber dressing demonstrated ~three times higher sorptivity and better durability, withstanding ~five times greater strain energy than the other product before failure occurred. This work paves the way for quantitative, standardised testing of dressings in all aspects of exudate management. The reported tests are further suitable for testing dressing combinations or how dressings interact with negative pressure wound therapy.  相似文献   
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ObjectiveTo assess the characteristics of cooking-related burn injuries in children reported to the World Health Organization Global Burn Registry.MethodsOn 1 February 2021, we downloaded data from the Global Burn Registry on demographic and clinical characteristics of patients younger than 19 years. We performed multivariate regressions to identify risk factors predictive of mortality and total body surface area affected by burns.FindingsOf the 2957 paediatric patients with burn injuries, 974 involved cooking (32.9%). More burns occurred in boys (532 patients; 54.6%) than in girls, and in children 2 years and younger (489 patients; 50.2%). Accidental contact and liquefied petroleum caused most burn injuries (729 patients; 74.8% and 293 patients; 30.1%, respectively). Burn contact by explosions (odds ratio, OR: 2.8; 95% confidence interval, CI: 1.4–5.7) or fires in the cooking area (OR: 3.0; 95% CI: 1.3–6.8), as well as the cooking fuels wood (OR: 2.2; 95 CI%: 1.3–3.4), kerosene (OR: 1.9; 95% CI: 1.0–3.6) or natural gas (OR: 1.5; 95% CI: 1.0–2.2) were associated with larger body surface area affected. Mortality was associated with explosions (OR: 7.5; 95% CI: 2.2–25.9) and fires in the cooking area (OR: 6.9; 95% CI: 1.9–25.7), charcoal (OR: 4.6; 95% CI: 2.0–10.5), kerosene (OR: 3.9; 95% CI: 1.4–10.8), natural gas (OR: 3.0; 95% CI: 1.5–6.1) or wood (OR: 2.8; 95% CI: 1.1–7.1).ConclusionPreventive interventions directed against explosions, fires in cooking areas and hazardous cooking fuels should be implemented to reduce morbidity and mortality from cooking-related burn injuries.  相似文献   
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