235 research outputs found
Inhabiting infrastructure: exploring the interactional spaces of urban cycling
Contemporary cities are thick with infrastructure. In recognition of this fact a great deal of recent work within urban studies and urban geography has focused on transformations in the governance and ownership of infrastructural elements within cities. Less attention has been paid to the practices through which urban infrastructures are inhabited by urban dwellers. Yet in all sorts of ways infrastructures are realised through their use and inhabitation. This paper argues for the importance of attending to the ways that infrastructures are reinterpreted through use. Focusing on a case study of commuter cyclists in London, it explores the ways in which cyclists accommodate themselves to (and are in turn accommodated by) the infrastructural orderings of London’s streets. Confronted by the obduracy of a road infrastructure designed primarily for motorised traffic, cyclists show a diverse range of approaches to negotiating movement through the city on bikes. The paper describes how this negotiation can be understood in terms of the more or less skilful processes of navigation, rule following, rule making, and rule bending. This involves a polymorphous mix of practices, some common to driving, others to walking, and yet others unique to cycling. In conclusion, the paper suggests that transformations of infrastructures found within cities need to be understood as much through emergent changes between their elements, and that close attention to how infrastructures come to be inhabited offers productive avenues for thinking about ways to improve them
Molecular lymph node staging with one-step nucleic acid amplification and its prognostic value for patients with colon cancer: the first follow-up study
Background Molecular lymph node workup with one-step nucleic acid amplification (OSNA) is a validated diagnostic adjunct in breast cancer and also appealing for colon cancer (CC) staging. This study, for the first time, evaluates the prognostic value of OSNA in CC. Patients and methods The retrospective study includes patients with stage I-III CC from three centres. Lymph nodes were investigated with haematoxylin and eosin (H&E) and with OSNA, applying a 250 copies/mu L threshold of CK19 mRNA. Diagnostic value of H&E and OSNA was assessed by survival analysis, sensitivity, specificity and time-dependent receiver operating characteristic curves. Results Eighty-seven patients were included [mean follow-up 53.4 months (+/- 24.9)]. Disease recurrence occurred in 16.1% after 19.8 months (+/- 12.3). Staging with H&E independently predicted worse cancer-specific survival in multivariate analysis (HR = 10.77, 95% CI 1.07-108.7, p = 0.019) but not OSNA (HR = 3.08, 95% CI 0.26-36.07, p = 0.197). With cancer-specific death or recurrence as gold standard, H&E sensitivity was 46.7% (95% CI 21.3-73.4%) and specificity 84.7% (95% CI 74.3-92.1%). OSNA sensitivity and specificity were 60.0% (95% CI 32.3-83.7%) and 75.0% (95% CI 63.4-84.5%), respectively. Conclusions In patients with CC, OSNA does not add relevant prognostic value to conventional H&E contrasting findings in other cancers. Further studies should assess lower thresholds for OSNA (< 250 copies/mu L).Surgical oncolog
Safety and effectiveness of bariatric surgery: Roux-en-Y gastric bypass is superior to gastric banding in the management of morbidly obese patients
<p>Abstract</p> <p>Background</p> <p>The use of bariatric surgery in the management of morbid obesity is rapidly increasing. The two most frequently performed procedures are laparoscopic Roux-en-Y bypass and laparoscopic gastric banding. The objective of this short overview is to provide a critical appraisal of the most relevant scientific evidence comparing laparoscopic gastric banding versus laparoscopic Roux-en-Y bypass in the treatment of morbidly obese patients.</p> <p>Results and discussion</p> <p>There is mounting and convincing evidence that laparoscopic gastric banding is suboptimal at best in the management of morbid obesity. Although short-term morbidity is low and hospital length of stay is short, the rates of long-term complications and band removals are high, and failure to lose weight after laparoscopic gastric banding is prevalent.</p> <p>Conclusion</p> <p>The placement of a gastric band appears to be a disservice to many morbidly obese patients and therefore, in the current culture of evidence based medicine, the prevalent use of laparoscopic gastric banding can no longer be justified. Based on the current scientific literature, the laparoscopic gastric bypass should be considered the treatment of choice in the management of morbidly obese patients.</p
Prescribing Challenges after Bariatric Surgery
Obesity is an increasing problem in the UK, with over half the population being overweight or obese. The use of gastric surgery is increasing, with a 5% increase in 2016/17 compared to 2015/16. However, little is known about ideal drug formulations after bariatric surgery. An exploratory literature search of research databases was carried out to address this. We found that there was a dearth of high-quality primary studies available, with many studies using low numbers of participants. The major finding was of the need for increased vigilance and monitoring of patients after surgery
Synthetic microparticles conjugated with VEGF165 improve the survival of endothelial progenitor cells via microRNA-17 inhibition
Several cell-based therapies are under pre-clinical and clinical evaluation for the treatment of ischemic diseases. Poor survival and vascular engraftment rates of transplanted cells force them to work mainly via time-limited paracrine actions. Although several approaches, including the use of soluble vascular endothelial growth factor (sVEGF)-VEGF165, have been developed in the last 10 years to enhance cell survival, they showed limited efficacy. Here, we report a pro-survival approach based on VEGF-immobilized microparticles (VEGF-MPs). VEGF-MPs prolong VEGFR-2 and Akt phosphorylation in cord blood-derived late outgrowth endothelial progenitor cells (OEPCs). In vivo, OEPC aggregates containing VEGF-MPs show higher survival than those treated with sVEGF. Additionally, VEGF-MPs decrease miR-17 expression in OEPCs, thus increasing the expression of its target genes CDKN1A and ZNF652. The therapeutic effect of OEPCs is improved in vivo by inhibiting miR-17. Overall, our data show an experimental approach to improve therapeutic efficacy of proangiogenic cells for the treatment of ischemic diseases.Soluble vascular endothelial growth factor (VEGF) enhances vascular engraftment of transplanted cells but the efficacy is low. Here, the authors show that VEGF-immobilized microparticles prolong survival of endothelial progenitors in vitro and in vivo by downregulating miR17 and upregulating CDKN1A and ZNF652
Laser-induced modification of the patellar ligament tissue: comparative study of structural and optical changes
The effects of non-ablative infrared (IR) laser treatment of collagenous tissue have been commonly interpreted in terms of collagen denaturation spread over the laser-heated tissue area. In this work, the existing model is refined to account for the recently reported laser-treated tissue heterogeneity and complex collagen degradation pattern using comprehensive optical imaging and calorimetry toolkits. Patella ligament (PL) provided a simple model of type I collagen tissue containing its full structural content from triple-helix molecules to gross architecture. PL ex vivo was subjected to IR laser treatments (laser spot, 1.6 mm) of equal dose, where the tissue temperature reached the collagen denaturation temperature of 60 ± 2°C at the laser spot epicenterin the first regime, and was limited to 67 ± 2°C in the second regime. The collagen network was analyzed versus distance from the epicenter. Experimental characterization of the collagenous tissue at all structural levels included cross-polarization optical coherence tomography, nonlinear optical microscopy, light microscopy/histology, and differential scanning calorimetry. Regressive rearrangement of the PL collagen network was found to spread well outside the laser spot epicenter (>2 mm) and was accompanied by multilevel hierarchical reorganization of collagen. Four zones of distinct optical and morphological properties were identified, all elliptical in shape, and elongated in the direction perpendicular to the PL long axis. Although the collagen transformation into a random-coil molecular structure was occasionally observed, it was mechanical integrity of the supramolecular structures that was primarily compromised. We found that the structural rearrangement of the collagen network related primarily to the heat-induced thermo-mechanical effects rather than molecular unfolding. The current body of evidence supports the notion that the supramolecular collagen structure suffered degradation of various degrees, which gave rise to the observed zonal character of the laser-treated lesion
Circulating soluble Fas levels and risk of ovarian cancer
BACKGROUND: Dysregulation of apoptosis, specifically overexpression of soluble Fas (sFas), has been proposed to play a role in the development of ovarian cancer. The main objective of the present study was to evaluate serum sFas as a potential biomarker of ovarian cancer risk. METHODS: The association between serum sFas levels and the risk of ovarian cancer was examined in a case-control study nested within three prospective cohorts in New York (USA), Umeå (Sweden), and Milan (Italy). Case subjects were 138 women with primary invasive epithelial ovarian cancer diagnosed between 2 months and 13.2 years after the initial blood donation. Control subjects were 263 women who were free of cancer, and matched the case on cohort, menopausal status, age, and enrollment date. Serum sFas levels were determined using a quantitative sandwich enzyme immunoassay. RESULTS: Serum sFas levels were similar in women subsequently diagnosed with ovarian cancer (median, 6.5 ng/mL; range, 4.4 – 10.2) and in controls (median, 6.8 ng/mL; range, 4.5 – 10.1). Statistically significant trends of increasing serum sFas with age were observed among cases (r = 0.39, p < 0.0001) and controls (r = 0.42, p < 0.0001). Compared to women in the lowest third, women in the highest third of serum sFas were not at increased risk of ovarian cancer after adjustment for potential confounders (odd ratio (OR), 0.87; 95% confidence interval (CI), 0.42 – 1.82). CONCLUSION: The results suggest that serum sFas may not be a suitable marker for identification of women at increased risk of ovarian cancer
Combination of letrozole, metronomic cyclophosphamide and sorafenib is well-tolerated and shows activity in patients with primary breast cancer
PURPOSE: To assess whether the combination of letrozole, metronomic cyclophosphamide and sorafenib (LCS) is well tolerated and shows activity in primary breast cancer (BC). METHODS:Thirteen oestrogen receptor-positive, postmenopausal, T2-4, N0-1 BC patients received the LCS combination for 6 months. In these patients we examined the pharmacokinetics of sorafenib and cyclophosphamide, toxicity of the regimen, the clinical response to therapy and changes in the levels of biologically relevant biomarkers. RESULTS:Adequate plasma concentrations of sorafenib were achieved in patients when it was dosed in combination with L+C. The mean plasma concentrations of C were consistently lower following administration of LCS, compared with administration of L+C only. The most common drug-related grade 3/4 adverse events were skin rash (69.3%), hand-foot skin reaction (69.3%) and diarrhoea (46.1%). According to RECIST Criteria, a clinical complete response was observed in 6 of 13 patients. A significant reduction in tumour size, evaluated with MRI, was also observed between baseline and 14 days of treatment in all 13 patients (P=0.005). A significant reduction in SUV uptake, measured by (18)FDG-PET/CT, was observed in all patients between baseline and 30 days of treatment (P=0.015) and between baseline and definitive surgery (P=0.0002). Using modified CT Criteria, a response was demonstrated in 8 out of 10 evaluable patients at 30 days and in 11 out of 13 evaluable patients at the definitive surgery. A significant reduction in Ki67 expression was observed in all patients at day 14 compared with baseline (P<0.00001) and in 9 out of 13 patients at the definitive surgery compared with baseline (P<0.03). There was also a significant suppression of CD31 and VEGF-A expression in response to treatment (P=0.01 and P=0.007, respectively).CONCLUSIONS:The LCS combination is feasible and tolerable. The tumour response and target biomarker modulation indicate that the combination is clinically and biologically active
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