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Virtual Reality applications are predicted to create a paradigm shift in education, but there is little empirical evidence of their educational value. Virtual Reality affordances to support language learning have not yet been realized. This quasi-experimental study investigated the effect of a Virtual Reality application on foreign language learning and compared engagement, engrossment, and immersion between two versions of the application (Virtual Reality and mobile). Twenty experimental group undergraduate students used a head-mounted Virtual Reality display and twenty control group students used a mobile application for learning Italian as a foreign language. Data sources included: (a) a 10 open-ended questions pre-test and post-test measuring vocabulary skills, and (b) a validated questionnaire with 21 seven-point Likert scale items measuring engagement, engrossment, and immersion. Findings revealed a statistically significant difference in the experimental group students’ vocabulary performance when students’ pre-test and post-test scores were compared. Engagement, engrossment, and immersion received relatively high scores by Virtual Reality participants. The study did not find a statistically significant difference between the two conditions. The study provides preliminary empirical data indicating that Virtual Reality applications can be both effective and engaging for language learning, even though they were not found to be superior to mobile applications.

PurposeSustained delivery of regenerative retinal therapies by robotic systems requires intra-operative tracking of the retinal fundus. We propose a supervised deep convolutional neural network to densely predict semantic segmentation and optical flow of the retina as mutually supportive tasks, implicitly inpainting retinal flow information missing due to occlusion by surgical tools.MethodsAs manual annotation of optical flow is infeasible, we propose a flexible algorithm for generation of large synthetic training datasets on the basis of given intra-operative retinal images. We evaluate optical flow estimation by tracking a grid and sparsely annotated ground truth points on a benchmark of challenging real intra-operative clips obtained from an extensive internally acquired dataset encompassing representative vitreoretinal surgical cases.ResultsThe U-Net-based network trained on the synthetic dataset is shown to generalise well to the benchmark of real surgical videos. When used to track retinal points of interest, our flow estimation outperforms variational baseline methods on clips containing tool motions which occlude the points of interest, as is routinely observed in intra-operatively recorded surgery videos.ConclusionsThe results indicate that complex synthetic training datasets can be used to specifically guide optical flow estimation. Our proposed algorithm therefore lays the foundation for a robust system which can assist with intra-operative tracking of moving surgical targets even when occluded.

This paper addresses retinal vessel segmentation on optical coherence tomography angiography (OCT-A) images of the human retina. Our approach is motivated by the need for high precision image-guided delivery of regenerative therapies in vitreo-retinal surgery. OCT-A visualizes macular vasculature, the main landmark of the surgically targeted area, at a level of detail and spatial extent unattainable by other imaging modalities. Thus, automatic extraction of detailed vessel maps can ultimately inform surgical planning. We address the task of delineation of the Superficial Vascular Plexus in 2D Maximum Intensity Projections (MIP) of OCT-A using convolutional neural networks that iteratively refine the quality of the produced vessel segmentations. We demonstrate that the proposed approach compares favourably to alternative network baselines and graph-based methodologies through extensive experimental analysis, using data collected from 50 subjects, including both individuals that underwent surgery for structural macular abnormalities and healthy subjects. Additionally, we demonstrate generalization to 3D segmentation and narrower field-of-view OCT-A. In the future, the extracted vessel maps will be leveraged for surgical planning and semi-automated intraoperative navigation in vitreo-retinal surgery.

The lymphatic system is a complicated system consisting of the lymphatic vessels and lymph nodes draining the extracellular fluid containing cellular debris, excess water and toxins to the circulatory system. The lymph nodes serve as a filter, thus, when the lymph fluid returns to the heart, it is completely sterile. In addition, the lymphatic system includes the mucosa-associated lymphoid tissue, such as tonsils, adenoids, Peyers patches in the small bowel and even the appendix. Taking advantage of the drainage system of the lymphatics, cancer cells enter the lymphatic vessels and then the lymph nodes. In general, the lymph nodes may serve as a gateway in the majority of cases in early cancer. Occasionally, the cancer cells may enter the blood vessels. This review article emphasizes the structural integrity of the lymphatic system through which cancer cells may spread. Using melanoma and breast cancer sentinel lymph node model systems, the spread of early cancer through the lymphatic system is progressive in a majority of cases. The lymphatic systems of the internal organs are much more complicated and difficult to study. Knowledge from melanoma and breast cancer spread to the sentinel lymph node may establish the basic principles of cancer metastasis. The goal of this review article is to emphasize the complexity of the lymphatic system. To date, the molecular mechanisms of cancer spread from the cancer microenvironment to the sentinel lymph node and distant sites are still poorly understood and their elucidation should take major priority in cancer metastasis research.

Immune checkpoint inhibitors by blocking specific inhibitory pathways induce T-cell-mediated tumor lysis. However, many remain to be elucidated about their effect on human humoral immunity. We evaluated the effect of the PD1 inhibitor nivolumab on humoral immunity by following the levels of antibodies against hepatitis B surface antigen (anti-HBs) in a hemodialysis patient successfully vaccinated against hepatitis B virus 5 years ago and now starting nivolumab for renal cell carcinoma lung metastases. Anti-HBs kinetics after administration of an extra vaccine dose were also evaluated. Nivolumab increased anti-HBs and facilitated a further increase following an additional vaccine dose. The observed time frame indicates that nivolumab boosts humoral immune response by affecting long-lived plasma cells and at least memory B cells. This may protect cancer patients from pathogens encountered in the past or against which vaccination has been performed and provide information for the emerging immune checkpoint inhibitors administration concept against chronic infectious diseases.

Background: Many lines of evidence highlight the genetic contribution on the development of diabetic nephropathy (DN). One of the studied genes is SERPINE1 whose the role in the risk of developing DN remains questionable. In order to elucidate the contribution of SERPINE1 in DN progression in the context of type 2 diabetes mellitus (T2DM), we conducted an association study and meta-analysis of SERPINE1 genetic variants. Materials and Methods: A total of 190 patients with DN, 150 T2DM (type 2 diabetes mellitus) patients without DN and 238 healthy controls were recruited. We selected five tag single-nucleotide polymorphisms (SNPs) from the HapMap. The generalized odds ratio (ORG) was calculated to estimate the risk on DN development. Subgroup analyses based on ethnicity and type of diabetes were also performed. Results: Both the present association study regarding SERPINE1 SNPs (rs2227667, rs2070682, rs1050813, rs2227690, rs2227692) did not found any significant association between SERPINE1 variants and DN and the meta-analysis of variant 4G>5G (rs1799889) did not also reveal a significant association between 4G>5G variant and DN in main and subgroup analyses. Discussion: In conclusion, the present association study and meta-analysis provides strong evidence that SERPINE1 genetic variant 4G>5G is not implicated in the risk or development of DN in Caucasians. Further studies in other populations remain to further investigate the role of this variant in the course of DN.

International audience; BACKGROUND:Two-stage hepatectomy of bilobar colorectal liver metastases is widely used and shows encouraging survival results. However, the risk of dropout after the first stage remains high and is associated with poor survival. The objective of our study was to evaluate the factors associated with long-term survival based on the pathologic response to preoperative systemic chemotherapy in colorectal liver metastases patients who underwent two-stage hepatectomy.METHODS:The pathologic response to preoperative chemotherapy and its effect on second-stage completion and survival were retrospectively evaluated in 67 patients treated between 2003 and 2013.RESULTS:A total of 56 patients underwent two-stage hepatectomy for initially nonresectable colorectal liver metastases. Chemotherapy was combined with a biotherapy in 32 cases. The tumor regression grade, modified tumor regression grade, and Blazer grade were used to classify patients as responders (tumor regression grade and modified tumor regression grade 1-3, Blazer 0-1) or nonresponders (tumor regression grade and modified tumor regression grade 4-5, Blazer 2) after the first stage. Tumor response in the three classifications was associated with second-stage completion (tumor regression grade 1-3: OR = 4.01, 95% CI: 1.12-14.36, P = .033; modified tumor regression grade 1-3: OR = 3.8, 95% CI: 1.13-12.6, P = .03; Blazer 0-1: OR = 5.45, 95% CI: 1.66-17.85, P = .005). Triple chemotherapy was also associated with responders. The median overall survival of responders was significantly higher (Blazer 0-1: 42.9 months versus Blazer 2: 20.1 months, P = .018; tumor regression grade 1-3: 42.9 months versus tumor regression grade 4-5: 25.1 months, P = .04).CONCLUSION:A pathologic response to chemotherapy is associated with second-stage completion and longer survival. Further studies are needed to achieve the early identification of patients for whom the benefit of the second surgical stage is less straightforward.

Chronic kidney disease (CKD) is an important global public health problem due to its high prevalence and morbidity. Although the treatment of nephrology patients has changed considerably, ineffectiveness and side effects of medications represent a major issue. In an effort to elucidate the contribution of genetic variants located in several genes in the response to treatment of patients with CKD, we performed a systematic review and meta-analysis of all available pharmacogenetics studies. The association between genotype distribution and response to medication was examined using the dominant, recessive, and additive inheritance models. Subgroup analysis based on ethnicity was also performed. In total, 29 studies were included in the meta-analysis, which examined the association of 11 genes (16 polymorphisms) with the response to treatment regarding CKD. Among the 29 studies, 18 studies included patients with renal transplantation, 8 involved patients with nephrotic syndrome, and 3 studies included patients with lupus nephritis. The present meta-analysis provides strong evidence for the contribution of variants harbored in the ABCB1, IL-10, ITPA, MIF, and TNF genes that creates some genetic predisposition that reduces effectiveness or is associated with adverse events of medications used in CKD.

Our work proposes neural network design choices that set the state-of-the-art on a challenging public benchmark on cataract surgery, CaDIS. Our methodology achieves strong performance across three semantic segmentation tasks with increasingly granular surgical tool class sets by effectively handling class imbalance, an inherent challenge in any surgical video. We consider and evaluate two conceptually simple data oversampling methods as well as different loss functions. We show significant performance gains across network architectures and tasks especially on the rarest tool classes, thereby presenting an approach for achieving high performance when imbalanced granular datasets are considered. Our code and trained models are available at https://github.com/RViMLab/MICCAI2021_Cataract_semantic_segmentation and qualitative results on unseen surgical video can be found at https://youtu.be/twVIPUj1WZM.

Effective treatment of degenerative retinal diseases will require robot-assisted intraretinal therapy delivery supported by excellent retinal layer visualisation capabilities. Intra-operative Optical Coherence Tomography (iOCT) is an imaging modality which provides real-time, cross-sectional retinal images partially allowing visualisation of the layers where the sight restoring treatments should be delivered. Unfortunately, iOCT systems sacrifice image quality for high frame rates, making the identification of pertinent layers challenging. This paper proposes a Super-Resolution pipeline to enhance the quality of iOCT images leveraging information from iOCT 3D cube scans. We first explore whether 3D iOCT cube scans can indeed be used as high-resolution images by performing Image Quality Assessment. Then, we apply non-rigid image registration to generate partially aligned pairs, and we carry out data augmentation to increase the available training data. Finally, we use CycleGAN to transfer the quality between low-resolution (LR) and high-resolution (HR) domain. Quantitative analysis demonstrates that iOCT quality increases with statistical significance, but a qualitative study with expert clinicians is inconclusive with regards to their preferences.

Introduction Pseudomyxoma peritonei (PMP) is a rare disease characterized by the progressive accumulation of mucinous ascites and peritoneal implants. The optimal treatment for PMP includes the association of complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC). For patients with a large burdensome disease, the completeness of cytoreduction sometimes requires maximal effort surgery. The aim of this article is to provide proof of concept for two stage cytoreductive surgery (CRS) in this category of patients. Methods and materials A two stage CRS and HIPEC with oxaliplatin was proposed for patients with bulky PMP including important involvement of the serosal surfaces of the bowel or colon who had an impaired nutritional status. The residual disease at the end of the first stage was less than 5 mm of thickness on several implants. Clinical, surgical and histopathological variables were analyzed. Results All eight patients completed the two-stage strategy. Mortality was nil. One Clavien Dindo grade 3 event occurred in each stage. After a median follow up of 29.5 months, all patients were alive and free of recurrence. All of the patients had histopathological complete response on the specimens obtained from the residual sites during the second stage surgery. Conclusions Two-stage surgical strategy is feasible for bulky PMP patients and it is associated with little high-grade morbidity and enhanced visceral sparing.

An association study was conducted to investigate the relation between 14 variants of glucose transporter 1 gene (SLC2A1) and the risk of type 2 diabetes (T2DM) leading to nephropathy. We also performed a meta-analysis of 11 studies investigating association between diabetic nephropathy (DN) and SLC2A1 variants. The cohort included 197 cases (T2DM with nephropathy), 155 diseased controls (T2DM without nephropathy) and 246 healthy controls. The association of variants with disease progression was tested using generalized odds ratio (ORG). The risk of type 2 diabetes leading to nephropathy was estimated by the OR of additive and co-dominant models. The mode of inheritance was assessed using the degree of dominance index (h-index). We synthesized results of 11 studies examining association between 5 SLC2A1 variants and DN. ORG was used to assess the association between variants and DN using random effects models. Significant results were derived for co-dominant model of rs12407920 [OR = 2.01 (1.17–3.45)], rs841847 [OR = 1.73 (1.17–2.56)] and rs841853 [OR = 1.74 (1.18–2.55)] and for additive model of rs3729548 [OR = 0.52 (0.29–0.90)]. The mode of inheritance for rs12407920, rs841847 and rs841853 was ‘dominance of each minor allele’ and for rs3729548 ‘non-dominance’. Frequency of one haplotype (C-G-G-A-T-C-C-T-G-T-C-C-A-G) differed significantly between cases and healthy controls [p = .014]. Regarding meta-analysis, rs841853 contributed to an increased risk of DN [(ORG = 1.43 (1.09–1.88) ORG = 1.58 (1.01–2.48)] between diseased controls versus cases and healthy controls versus cases, respectively. Further studies confirm the association of rs12407920, rs841847, rs841853, as well as rs3729548 and the risk of T2DM leading to nephropathy. 40 1 561 576

Background Hyperuricemia is common among kidney transplant recipients and has been associated with worse graft outcome. Since episodes of acute cellular rejection and chronic humoral rejection contribute to decreased graft survival, in this study the effect of uric acid on cellular and humoral alloimmunity was evaluated. Methods Cellular alloimmunity was assessed by cell proliferation in two-way mixed lymphocyte reaction (MLR) with human peripheral blood mononuclear cells (PBMC). For assessing humoral alloimmunity we developed a method in which humoral alloimmunity was induced in one-way MLR. Then the de novo production of alloantibodies was measured with an antibody-mediated complement-dependent cytotoxicity assay, in which supernatants from the above MRLs were used against resting PBMC similar to the stimulator cells of the above MLRs. Results Uric acid at a concentration above its crystallization threshold increased cellular proliferation in two-way MLRs. Supernatants from one-way MLRs performed in the presence of uric acid were more cytotoxic against PBMC from individuals that had conferred the stimulator cells for the above MLRs. Conclusions Uric acid increases both cellular and humoral alloimmunity in human PBMC. These results offer a possible pathogenetic mechanism for the observed relation between hyperuricemia and worse kidney allograft survival.

Graphical abstract, Today there is plausible evidence both on experimental and epidemiological basis, that hyperuricemia represents a risk factor for the development and progression of chronic kidney disease (CKD). Nevertheless, the role of serum uric acid lowering treatment in CKD is still a matter of serious controversy. Review of randomised controlled trials, suggests that there may be an improvement of renal function with allopurinol treatment in CKD stage 3–5. However, these studies have included a relatively limited number of participants and provide insufficient information on adverse events and on the incidence of the end stage renal disease. Therefore, before adequately powered randomised, placebo-controlled trials are completed we cannot recommend treating asymptomatic hyperuricemia in patients with CKD.

Background Essential Skills in the management of Surgical Cases – ESMSC is an International Combined Applied Surgical Science and Wet Lab course aimed at the undergraduate level. ESMSC combines interactive basic science workshops and case-based learning, with basic surgical training modules (BST) on Ex Vivo and In Vivo swine model. In Vivo Dissections include more advanced modules i.e. Abdominal Anatomy Dissections and Cardiac Transplant. Aim To evaluate the educational environment of a novel course, as well as to compare Medical students' perceptions across various groups. Materials and Methods 83 Delegates from King's College London (KCL) and several Hellenic Medical Schools attended the ESMSC course. The DREEM inventory was distributed upon completion of the modules. Results The mean overall score for DREEM inventory was 148.05/200(99–196, SD = 17.90). Cronbach's Alpha value was 0.818, indicating good internal consistency of the data. Year 3/4 Students have a significantly positive “Perception of Learning”, when compared to Year 5/6 (36.43 vs. 33.75, p = 0.017). KCL Students have a more positive view of the course compared to their Greek counterparts (155.19 vs. 145.62/200, p = 0.034). No statistical significant difference was noted when comparing male vs. female students (p > 0.05). Conclusions Students seem to positively rate the ESMSC educational environment. Junior as well as KCL students appear to be more enthusiastic. Further research should focus on the optimal strategy for early involvement and motivation of various students' groups in BST., Highlights • ESMSC is an International Surgical Science and Wet Lab course aimed at undergraduates. • Students seem to positively rate the ESMSC educational environment. • Year 3/4 Students have a significantly positive “Perception of Learning”, when compared to Year 5/6. • KCL Students gave a more feedback on the course compared to their Greek counterparts. • Further research should focus on involving and motivating students early in BST.

Glucotoxicity in renal tubular epithelial cells (RPTECs) contributes to the pathogenesis of diabetic nephropathy. Sodium-glucose cotransporter 2 (SGLT2) inhibitors may exert their renoprotective effect by preventing glucotoxicity. We tested whether the confirmed in capillary endothelial cells unifying model of glucotoxicity can be applied in RPTECs and the impact of dapagliflozin. In primary human RPTECs cultured in normal or high glucose medium in the presence or not of dapagliflozin, we assessed glucose consumption, SCLT2 expression, reactive oxygen species (ROS) production, glyceraldehyde 3-phosphate dehydrogenase (GAPDH) activity, d-sorbitol and methylglyoxal cell content, O-linked β-N-acetyl glucosamine (O-Glc-NAc)-modified proteins, protein kinase C (PKC) activity, transforming growth factor-β1 (TGF-β1), interleukin-8 (IL-8), cell necrosis, and cell apoptosis using colorimetric and immunoenzymatic assays, and western blotting. High glucose increases SGLT2 expression and glucose consumption. ROS are overproduced, and GAPDH is inhibited. The accumulation due to GAPDH inhibition glycolytic products are diverted into four noxious pathways. The polyol pathway assessed by d-sorbitol, the hexosamine pathway determined by O-GlcNAc-modified proteins, the lipid synthesis pathway assessed by PKC activity, and the advanced glycation end-products (AGEs) formation assessed by methylglyoxal. Eventually, these paths lead to overproduction of TGF-β1 and IL-8, as well as to cell necrosis and apoptosis. Dapagliflozin ameliorates all the above cascade of events. Our results support a unifying model for glucotoxicity in RPTECs. Dapagliflozin by decreasing the elevated glucose influx into the RPTECs under high glucose conditions ameliorates glucotoxicity.

Considering the referred beneficial effects of protein restriction on diabetic nephropathy (DN) and the role of renal endothelium in its pathogenesis, we evaluated the effect of general control nonderepressible 2 (GCN2) kinase activation, a sensor of amino acid deprivation, on known detrimental molecular pathways in primary human glomerular endothelial cells (GEnC). GEnC were cultured under normal or high-glucose conditions in the presence or not of the GCN2 kinase activator, tryptophanol. Glucose transporter 1 (GLUT1) expression was assessed by western blotting and reactive oxygen species (ROS) using a fluorogenic probe. Activities of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and protein kinase C (PKC) were assessed by commercial activity assays, sorbitol colorimetrically, methylglyoxal by ELISA and O-linked β-N-acetyl glucosamine (O-GlcNAc)-modified proteins by western blotting. High glucose induced GLUT1 expression, increased ROS and inhibited GAPDH. Also it increased the polyol pathway product sorbitol, PKC activity, the level of the O-GlcNAc-modified proteins that produced by the hexosamine pathway and the advanced glycation endproducts’ precursor methylglyoxal. Co-treatment of GEnC with tryptophanol restored the above high-glucose-induced alterations. Activation of GCN2 kinase protects GEnC from high-glucose-induced harmful molecular pathways. By inhibiting concurrently many pathways involved in DN pathogenesis, GCN2 kinase may serve as a pharmaceutical target for the treatment of DN.

A 37-year-old hemodialysis patient appeared with unusual somnolence during 2 successive hemodialysis sessions. Blood gas analysis revealed hypercapnic respiratory failure and spirometry restrictive lung disease. After exclusion of other causes of restrictive lung disease with chest CT-scan and cerebrum MRI, electrophysiological study revealed myopathy. Because besides lordosis and limb-girdle gait the patient was ambulant the possibility of late-onset Pompe's disease was set and confirmed with evaluation of α-glucosidase activity and genetic analysis. Enzyme replacement therapy (ERT) with aglucosidase alfa was started. Due to inaccessibility of veins in the arm without the arteriovenous fistula, during the last 1 year, the patient received the ERT through the venous line of the hemodialysis circuit. Three years later the patient remains ambulant without the need of any assistant device and preserved his pulmonary function. This is the first described case of late-onset Pompe's disease in a hemodialysis patient treated with ERT.

Background: Iatrogenic perforation during therapeutic colonoscopy, reported in up to 1% of endoscopic mucosal resections (EMRs) and up to 14% of endoscopic submucosal dissections (ESDs), has conventionally been an indication for surgery. Aims: We present a case series of successful endoscopic management of iatrogenic colorectal perforation during EMR and ESD, demonstrating the feasibility and safety of the method. Methods: Retrospective analysis of a database of patients undergoing EMR and ESD for colorectal polyps in a tertiary referral centre in the United Kingdom. Results: Four cases of perforation were identified (two EMRs and two ESDs) in a series of 218 procedures (1.8%), all detected at the time of endoscopy and managed with endoscopic clips. Patients were observed in hospital and treated with antibiotics. Their median length of stay was 3 days (range 2–6 days), with no mortality or need for surgery. Conclusion: Surgery is no longer the first choice in the management of iatrogenic perforations during EMR and ESD for colorectal polyps; in selected patients with small perforations and minimal extraluminal contamination, conservative management with application of endoscopic clips, antibiotics and close patient monitoring constitute a safe and effective treatment option, avoiding the morbidity of major surgery.

Evaluation of the adequacy of endoscopic mucosal resection (EMR) of gastrointestinal lesions remains challenging by use of conventional endoscopy. Confocal laser endomicroscopy (CLE) is a novel imaging technique, designed to provide in vivo histology, and facilitate diagnosis with real-time intervention. We undertook a systematic review of the available literature, exploring the role of CLE in assuring completeness of EMR of gastrointestinal lesions. The number of pertinent studies is very limited, including only 1 randomized controlled study and 2 prospective comparative case series. Per-lesion meta-analysis showed that the sensitivity of CLE for detection of residual neoplasia was 91% (95% confidence interval, 82.5%-96%) with specificity of 69% (95% confidence interval, 61%-77%), with significant heterogeneity noted in all outcomes. In conclusion, the evidence underpinning the usefulness of CLE in ensuring adequate EMR of gastrointestinal neoplasia is currently very weak, with limited promising results related to gastric and colorectal polyp resections.

Mitochondrial reactive oxygen species (ROS) overproduction in capillary endothelial cells is a prerequisite for the development of diabetic nephropathy. Inhibition of xanthine oxidase, another ROS generator, ameliorates experimental diabetic nephropathy. To test the hypothesis that the initial high glucose-induced ROS production by the mitochondria activates xanthine oxidase, which afterward remains as the major source of ROS, we cultured primary human glomerular endothelial cells (GEnC) under normal or high-glucose conditions, with or without the xanthine oxidase inhibitor allopurinol. ROS generation and nitric oxide synthase (NOS) activity were assessed by chemiluminescence or colorimetrically. Levels of intercellular adhesion molecule 1 (ICAM-1), p53 and phosphorylated p53 (p-p53) were assessed by western blotting. Allopurinol prevented high glucose-induced ROS generation indicating that xanthine oxidase is the major source of ROS. Allopurinol protected GEnC from endothelial dysfunction since it prevented the high glucose-induced decrease in NOS activity and increase in ICAM-1 expression. Allopurinol reduced p53 and p-p53 levels induced by high glucose suggesting an axis of xanthine oxidase-derived ROS, DNA damage, p53 stabilization and endothelial dysfunction that may contribute to the pathogenesis of diabetic nephropathy. Allopurinol protects GEnC from high glucose-induced ROS generation, p53 overexpression and endothelial dysfunction. These data provide a pathogenetic mechanism that supports the results of experimental and clinical studies about the beneficial effect of xanthine oxidase inhibitors on the development of diabetic nephropathy.

Acute cellular rejection is the major cause of immune-mediated graft failure early in the course of kidney transplantation, whereas chronic antibody-mediated rejection is a major contributor to graft loss in the late post-transplant phase. Based mainly on the results of short-term studies, the calcineurin inhibitor tacrolimus prevails over the mammalian target of rapamycin (mTOR) inhibitors. However, the toxicity profile of the two drug categories differs, making the interchange between them appealing. In this study, the effect of tacrolimus and of the mTOR inhibitor everolimus on cellular and humoral alloimmunity was evaluated. Cellular alloimmunity was assessed by cell proliferation in two-way mixed lymphocyte reaction (MLR) with human peripheral blood mononuclear cells (PBMC). For assessing humoral alloimmunity, we developed a method in which humoral alloimmunity was induced in a one-way MLR. The de novo production of alloantibodies was measured with an antibody-mediated complement-dependent cytotoxicity assay, in which supernatants from the above MLRs were used against resting PBMC similar to the stimulator cells of the forementioned MLRs. Tacrolimus and everolimus were used at concentrations near their upper recommended trough levels. In two-way MLRs, tacrolimus inhibited cell proliferation more than everolimus. In one-way MLRs, tacrolimus and everolimus decreased alloantibody production to the same extent. In human cell cultures, everolimus is inferior to tacrolimus in inhibiting cellular alloimmunity, but equally effective as regards humoral alloimmunity. Thus, everolimus might be a safe alternative in case of tacrolimus toxicity, particularly after the early period of kidney transplantation.

In this paper we investigate the influence of dielectric and magnetic losses of an Epoxy bonded Yttrium Iron Garnet (YIG-Epoxy) composite substrate on the performance of a reconfigurable microstrip patch antenna. The antenna under investigation is a microstrip patch antenna printed on a 60/40 w/w% YIG-Epoxy composite substrate and controlled by an externally applied DC magnetic field. It is observed that high dielectric losses of the composite substrate can dramatically deteriorate the radiation efficiency of the proposed antenna in the demagnetized state, while in the magnetized state the magnitude of the resonance linewidth (ΔH) of the composite substrate is the main parameter responsible for the reduction or improvement of the radiation efficiency. Considerable effort has been made to fabricate a YIG-Epoxy substrate with improved properties regarding dielectric loss tangent and magnetic resonance linewidth. The prototyping and characterization of a reconfigurable patch antenna on the “improved” YIG-Epoxy substrate is also presented.

Disturbed iron homeostasis contributes to resistance to recombinant human erythropoietin (rHuEpo) in hemodialysis (HD) patients. Although increased hepcidin, which downregulates the iron exporter ferroportin, had been incriminated, such an association has not been confirmed. Albeit not universally accepted, it has been supported that in case of copper deficiency, decreased activity of multicopper oxidases induces endocytosis and degradation of ferroportin. Ferroportin in monocytes, serum copper, ceruloplasmin and markers of iron status were measured, and associations with rHuEpo resistance index (ERI) were evaluated. After a 4-week washout period from iron treatment, 34 HD patients and 20 healthy volunteers enrolled in the study. Ferroportin was assessed by means of Western blotting, copper colorimetrically, whereas ceruloplasmin with enzyme-linked immunosorbent assay. Hemoglobin, serum iron, ferritin and transferrin saturation (TSAT) were also measured. Ferroportin in monocytes of HD patients was decreased. Serum copper, ceruloplasmin, iron and TSAT were decreased. No correlation between copper or ceruloplasmin and ferroportin was detected. ERI was negatively correlated with ferroportin and all the markers of iron adequacy, but not with copper or ceruloplasmin. Although copper deficiency and decreased ferroportin are common in HD patients, copper might not play role in ferroportin level in monocytes and in iron metabolism in this population.

A 77-year-old man, 11 years under chronic hemodialysis treatment for chronic renal failure of unknown origin, presented with anterior chest pain, dyspnea with paradoxical breathing, and sternal instability after a simple fall from a standing height. Patient underwent three-vessel coronary artery bypass grafting 31 months ago. Computed tomography with three-dimensional volume rendering showed sternal nonunion with a great gap between the two halves of the sternum and at least one fracture in the left half of the sternum. A successful surgical repair followed. Patient suffered from severe secondary hyperparathyroidism for many years. Despite treatment with sevelamer, paricalcitol and cinacalcet, intact parathyroid hormone was 1682 pg/mL. During the last 5 years, serum intact parathyroid hormone remained steadily above 1000 pg/mL. Patient refused parathyroidectomy in the past. We assume that long-lasting severe hyperparathyroidism contributed to this rare and life-threatening complication of median sternotomy in our patient, due to the detrimental effect of hyperparathyroidism on bone metabolism and its association with increased incidence of bone fractures and defect in bone fracture healing.

BackgroundPeritoneal carcinomatosis in colorectal cancer is an advanced stage of the disease where improved survival can be attained whenever the resection associated with hyperthermic intreperitoneal chemotherapy is possible. In unresectable cases, systemic chemotherapy is administered to obtain conversion to resectability but results have not yet been clearly evaluated. Local chemotherapy in this setting has been proven useful in several similar situations. The aim of the present pilot study was to evaluate the feasibility of pre-operative intraperitoneal chemotherapy with oxaliplatin in these patients.MethodsSix patients with unresectable peritoneal disease of colorectal origin were included in the study. An intraperitoneal implantable chamber catheter was inserted during the laparotomy that evaluated the extent of the peritoneal disease (peritoneal carcinomatosis index 25 to 39). Patients then underwent intraperitoneal chemotherapy with oxaliplatin 85 mg/m2 in combination with systemic chemotherapy (FOLFIRI or simplified LV5FU) and a targeted therapy every 2 weeks.ResultsTwo catheter perfusion incidents were reported due to the abdominal wall thickness. Two patients completed the four intraperitoneal (IP) chemotherapy cycles without major toxicity. One patient developed grade 3 or 4 diarrhea requiring a short intensive care unit (ICU) stay, though it is not clear whether the event was induced by intravenous irinotecan, IP oxaliplatin or the combination of both. Grade 3 fatigue and abdominal pain were also recorded. For one patient with aggressive disease, best supportive care was initiated after the first course of chemotherapy.ConclusionsOur study is the first to assess intraperitoneal oxaliplatin-based chemotherapy in the preoperative setting for patients with unresectable peritoneal metastases. The tolerance was acceptable for 85 mg/m2 IP oxaliplatin combined with systemic therapy in these patients. Our results justify carrying on with a phase I/II trial to determine the recommended dose of oxaliplatin in this clinical context and its efficacy.

We describe a case of a patient with a functional kidney transplant who was admitted to our department with clinically evident central vein stenosis (CVS) 7 years after the removal of a central venous catheter (CVC) from the right internal jugular vein. The catheter was used as a hemodialysis access for a 2-month period. In the interval before his last admission, the patient suffered two episodes of deep vein thrombosis. Investigation revealed heterozygosity for factor V Leiden, the most common inherited thrombophilia encountered in 5% of Caucasians, and anticoagulation treatment was started. Magnetic resonance angiography showed stenosis just after the convergence of the right subclavian vein with the internal jugular vein to the innominate vein. Transluminal angioplasty restored venous patency and right upper arm edema resolved. Coexistence of CVS, accompanied by hemodynamic changes and endothelial dysfunction, with thrombophilia fulfill all the elements of the Virchow's triad. Therefore, the patient was at great risk for central vein thrombosis, from which he was possibly protected by the early administration of anticoagulant treatment. This case indicates that CVS can be asymptomatic for several years after CVC removal and also raises the question if thrombophilia workup and investigation for CVS may be beneficial in every patient with CVC placement in order to avoid any harmful outcomes.

Studies detected an association between visfatin and markers of iron metabolism in patients with insulin resistance. In this study, such a relation was evaluated in hemodialysis (HD) patients. Also relations between visfatin and hepcidin, demands for recombinant human erythropoietin (rHuEpo), inflammation, and situations characterized by insulin resistance were evaluated.After a four-week washout period from iron treatment, 33 HD patients and 20 healthy volunteers enrolled in the study. Serum visfatin, hepcidin, and interleukin-6 (IL-6) were assessed by means of enzyme-linked immunosorbent assay. Hemoglobin, serum iron, ferritin, and transferrin saturation (TSAT) were also measured.Visfatin was markedly increased in HD patients. Visfatin levels did not differ between diabetics and non-diabetics. No relation was detected between visfatin and body mass index or IL-6 in HD patients. From the markers of iron metabolism, the hepcidin included, visfatin was related only to TSAT. A strong positive relation was revealed between visfatin and hemoglobin, whereas visfatin was inversely related to rHuEpo dose. Resistance to rHuEpo index was inversely and independently of TSAT related to visfatin.Visfatin is increased in HD patients and it is associated with decreased demands for rHuEpo.

Diabetic nephropathy is the leading cause of end-stage renal disease. Diabetes mellitus is characterized by generalized endothelial dysfunction. However, recent data also emphasizes the role of local renal endothelium dysfunction in the pathogenesis of diabetic nephropathy. Hyperglycemia triggers a complex network of signal-transduction molecules, transcription factors, and mediators that culminate in endothelial dysfunction. In the glomerulus, vascular endothelial growth factor-A (VEGF)-induced neoangiogenesis may contribute to the initial hyperfiltration and microalbuminuria due to increased filtration area and immaturity of the neovessels, respectively. However, subsequent decrease in podocytes number decreases VEGF production resulting in capillary rarefaction and decreased glomerular filtration rate (GFR). Decreased nitric oxide availability also plays a significant role in the development of advanced lesions of diabetic nephropathy through disruption of glomerular autoregulation, uncontrolled VEGF action, release of prothrombotic substances by endothelial cells and angiotensin-II-independent aldosterone production. In addition, disturbances in endothelial glycocalyx contribute to decreased permselectivity and microalbuminuria; whereas there are recent evidences that reduced glomerular fenestral endothelium leads to decreased GFR levels. Endothelial repair mechanisms are also impaired in diabetes, since circulating endothelial progenitor cells number is decreased in diabetic patients with microalbuminuria. Finally, in the context of elevated profibrotic cytokine transforming growth factor-β levels, endothelial cells also confer to the deteriorating process of fibrosis in advanced diabetic nephropathy through endothelial to mesenchymal transition.

Hemodialysis (HD) patients are characterized by impaired T-cell function at least in part because of T-cell zeta-chain downregulation due to inflammation. Angiogenin responds as an acute phase reactant, is increased in HD patients, suppresses T-cell function and increased angiogenin level is co-localized with T-cell zeta-chain downregulation in various pathologies. Angiogenin can inhibit translation of proteins, which lack internal ribosomal entry sites in the corresponding mRNAs. In this study, the possible effect of angiogenin on T-cell zeta-chain downregulation was evaluated. Thirty HD patients and 21 healthy volunteers participated. T-cell zeta-chain expression was assessed with flow cytometry, plasma angiogenin and serum IL-6 with ELISA and serum C-reactive protein with an immunoturbidimetric method. Two available software tools were used for predicting the presence or not of internal ribosomal entry sites in T-cell zeta-chain mRNA sequence. In silico analysis of T-cell zeta-chain mRNA sequence failed to reveal the presence of internal ribosomal entry sites. T-cell zeta-chain expression was lower in HD patients than in healthy volunteers (1.86 ± 0.63 vs. 4.73 ± 3.22). In HD patients, C-reactive protein as well as IL-6 were higher than in healthy volunteers (10.04 ± 15.13 mg/L vs. 3.43 ± 0.98 mg/L and 15.06 ± 13.08 pg/mL vs. 2.11 ± 2.10 pg/mL respectively). Angiogenin was higher in HD patients than in healthy volunteers (483.20 ± 154.07 ng/mL vs. 259.98 ± 64.15 ng/mL). Neither C-reactive protein, nor IL-6 was associated with angiogenin or T-cell zeta-chain expression. Angiogenin concentration was negatively related to the expression of T-cell zeta-chain (r = -0.410, P = 0.025). Increased angiogenin may contribute to decreased T-cell zeta-chain expression in HD patients.

Acquired immunity is impaired in hemodialysis (HD) patients, and decreased T-cell number may contribute. Indoleamine 2,3-dioxygenase (IDO) and arginase type I (ARG) catabolize tryptophane and arginine, respectively, and exert proapoptotic and antiproliferative effects on T-cells. Plasma levels of IDO and ARG and their relation to blood T-cell number were evaluated in HD patients.Thirty-two HD patients and 20 healthy controls participated in the study. Plasma IDO and ARG were measured by means of enzyme-linked immunosorbent assay. T-cell number was assessed by means of flow cytometry.IDO concentration was significantly higher in HD patients than in healthy volunteers (44.30 ± 31.83 ng/mL vs. 21.28 ± 26.21 ng/mL, p = 0.009). There was a trend for higher ARG concentration in HD patients (13.43 ± 11.91 ng/mL) than in healthy volunteers (9.56 ± 4.03 ng/mL), which, however, did not reach statistic significance (p = 0.099). Absolute T-cell count was significantly lower in HD patients than in healthy controls (1176.99 ± 567.71 cells/mm3 vs. 1519.85 ± 594.96 cells/mm3, p = 0.040). Absolute blood T-cell number was inversely related to plasma IDO (r = -0.490, p = 0.004) and to plasma ARG (r = -0.387, p = 0.029) concentrations.Plasma IDO and ARG may contribute to decreased blood T-cell count in HD patients.

Perilipin-1 surrounds lipid droplets in both adipocytes and in atheroma plaque foam cells and controls access of lipases to the lipid core. In hemodialysis (HD) patients, dyslipidemia, malnutrition, inflammation and atherosclerosis are common. Thirty-six HD patients and 28 healthy volunteers were enrolled into the study. Ten HD patients suffered from coronary heart disease (CHD). Perilipin-1, triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), body mass index, albumin, geriatric nutritional risk index, normalized protein catabolic rate, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were measured. Perilipin-1 did not differ between HD patients and healthy volunteers. IL-6 and TNF-α were higher in HD patients. The evaluated nutritional markers and the markers of inflammation did not differ between HD patients with high perilipin-1 levels and HD patients with low perilipin-1 levels. Regarding the lipid profile, only HDL-C differed between HD patients with high perilipin-1 levels and HD patients with low perilipin-1 levels, and it was higher in the first subgroup. Perilipin-1 was significantly higher in HD patients without CHD. Perilipin-1 is detectable in the serum of HD patients and it is associated with increased HDL-C and decreased incidence of CHD.

Objectives The aim of this study was to compare the effectiveness of atorvastatin with the sodium hyaluronate/carboxymethylcellulose (HA/CMC, Seprafilm; Genzyme; Genzyme Biosurgery Corporation, Cambridge, MA) in preventing postoperative intraperitoneal adhesion formation in rats. Methods Sixty Wistar rats underwent a laparotomy, and adhesions A were induced by cecal abrasion. The animals were divided into 4 groups: group 1, control A; group 2, (A + atorvastatin); group 3, (A + HA/CMC), and group 4, (A + atorvastatin + HA/CMC). The atorvastatin (groups 2 and 4) and HA/CMC (groups 3 and 4) were administered intraperitoneally before the abdominal wall was closed. After 14 days, adhesions were classified by 2 independent surgeons. Results The adhesion scores (mean ± standard deviation) for groups 1, 2, 3, and 4 were 2.93 ± .59, 1.85 ± 1.07, 1.80 ± .86, and 1.93 ± .70, respectively. The differences in adhesion scores among all 3 preventive groups (groups 2, 3, and 4) were statistically significant when compared with the control group ( P = .005, P = .002, and P = .009, respectively). Conclusions These data suggest that atorvastatin, administered intraperitoneally, is as effective as HA/CMC without an expectable additive effect in preventing postoperative adhesions in rats.

A 48-year-old man presented as an emergency with a 3-week history of rectal bleeding. Examination of his rectum revealed a circumferential tumour, 2 cm from the anal verge. An MRI scan reported a locally infiltrative mid-lower rectal tumour staged as T3d/T4 N2 MX. A colonoscopy revealed appearances of severe proctitis and biopsies did not show any evidence of dysplasia or malignancy. The patient was discussed at the regional colorectal cancer multidisciplinary team meeting with a management plan for neoadjuvant chemoradiotherapy following repeat biopsies, which were again negative for malignancy. He tested positive for the HIV and was referred to genitourinary medicine. A positive Chlamydia trachomatis nucleic acid test from a rectal swab was serovar L2 consistent with a diagnosis of lymphogranuloma venereum. He was treated with doxycycline and subsequent MRI scans showed reduction in tumour size with eventual resolution. This case report highlights the importance of HIV testing in patients with newly diagnosed colorectal tumours.

After a positive faecal occult blood test, a 60-year-old woman underwent a screening colonoscopy which identified a malignant-looking ulcer in the ascending colon. Biopsies from the lesion were inconclusive. A subsequent CT scan of the abdomen and pelvis commented on a polypoid lesion in the ascending colon. A colorectal cancer multidisciplinary team discussion concluded that a right hemicolectomy was indicated as the lesion was suspicious for malignancy. Intraoperatively, there was a firm ascending colon mass adherent to the abdominal wall, which was resected with clear margins. There were no other complications, and the patient was discharged without further issues. Histopathology from the retrieved specimen revealed a complete absence of malignancy, but rather, inflamed granulation tissue with ‘reaction to foreign birefringent material’—likely to represent a mesh from an incisional hernia repair 9 years previously. The patient is currently recovering well without complication.

Ischemic acute kidney injury is characterized by apoptosis of tubular epithelial cells. Proteasome plays a key role in cellular processes such as proliferation, apoptosis and inflammation. The results of animal studies about the effect of proteasome inhibitors on the course of ischemic acute kidney injury are controversial. Primary human renal tubular epithelial cells were cultured with or without the hypoxia mimetic CoCl2 and with or without the proteasome inhibitor CEP-18770 and/or the immunoproteasome inhibitor ONX-0914. The level of the proteasome subunit β5, the immunoproteasome subunits LMP7 and LMP2, the function of these proteolytic machines, HIF-1α and its transcriptional target lactate dehydrogenase-A, p53 and its transcriptional targets TP53-inducible glycolysis and apoptosis regulator and p21, and finally of activated cleaved caspase-3 were assessed by means of western blotting. CoCl2 decreased the expression of β5, LMP7 and LMP2, as well as the activity of proteasome and immunoproteasome. It increased HIF-1α and its function, along with p53 and its function and induced apoptosis. CEP-18770 and ONX-0914 induced the above alterations toward the same directions as CoCl2 does. In CoCl2-treated cells, pretreatment with CEP-18770 and/or ONX-0914 potentiates the changes induced by CoCl2 alone. CoCl2, CEP-18770 and ONX-0914 induce apoptosis in human renal tubular epithelial cells. Importantly, proteasome or immunoproteasome inhibitors are rather toxic than beneficial in human renal tubular epithelial cells treated with the hypoxia mimetic CoCl2.

The problem of scattering parameters (S 11 , S 21 ) for a rectangular waveguide (width a and height b) loaded with a dielectric and gyro tropic material of length d is considered, targeting the estimation of the electric permittivity and the parameters of the permeability tensor. The measurements are collected with a vector network analyzer equipped with a calibrated rectangular wave guide loaded with a parallelepiped Y 3 Fe 5 O 12 , with dimensions a s ≈ 3/4", b s ≈ 3/8" and length d ≈ 15.1 mm. The electric permittivity as a function of frequency is estimated by comparing the experimental measurements with the theoretically calculated, using a Debye type of relaxation for ϵ = ϵ' - j ϵ" with ϵ dc = 16.5 and relaxation time τ = 1 × 10 -15 s. The parameters of the magnetic permeability tensors are estimated by comparing the experimental data (|S 11 | and |S 21 |) measured under a dc-magnetic field with results of computer simulations.

We report on a broadband technique for making frequency-swept permeability measurements of magnetic thin films. The device is essentially a strip line short circuited to the ground plane. The measurement of the input impedance of the cell loaded with the sample is modeled appropriately with an equivalent electrical circuit and the complex permeability is deduced. The technique is applied in deducing the complex permeability of thin permalloy films deposited on Si(1 0 0) substrates in the frequency range from 200 MHz to 4 GHz.

An enlarging soft tissue mass was resected from the leg of a young man with neurofibromatosis type 1. Rhabdomyosarcomatous elements admixed with islands of osteoid and chondroid matrix was seen on microscopy. Based on immunohistochemistry, a malignant triton tumor, an uncommon subtype of peripheral nerve sheath tumor with rhabdomyosarcomatous elements, was diagnosed. The important feature of this neoplasm was that it showed pluridirectional differentiation to osteosarcoma and chondrosarcoma. This pathologic finding is rare and seen in only a few cases of all malignant triton tumors.