Unique report of iliocaval endovascular reconstruction successfully enabling a kidney transplant.

End-stage renal disease patients with Iliocaval venous obstruction are normally nom viable recipients for kidney transplantation. We report a case of a 34-year-old male patient in hemodialysis as renal replacement therapy for six years due to IgA nephropathy. Past medical history included multiple central venous catheter infections and catheter associated thrombosis. Iliac confluence and inferior vena cava occlusion previously excluded the patient from the renal transplantation list. Exhaustion of venous access sites was already previously documented. After multidisciplinary discussion the patients was proposed to endovascular Iliocaval reconstruction aiming a future kidney transplant. Iliocaval recanalization was achieved through bilateral femoral access. Inferior vena cava and iliac angioplasty were performed. A dedicated venous stent was deployed in the inferior vena cava, followed by a double-barrel reconstruction of the iliac confluence. Successful iliocaval recanalization was accomplished. Five months after kidney transplantation was performed with a deceased-donor graft in the right iliac fossa. Post operative period was uneventful. After 12 months the patient remained free from kidney replacement therapies with a serum creatinine of 1.3mg/dL. At the best of our knowledge this is the first clinical description of successful kidney transplant in a patient with a previous iliocaval reconstruction.

Proximalization of Arterial Inflow for the Treatment of Limb Ischemia in a Transposed Femoral Arteriovenous Fistula-A Case Report.

INTRODUCTION: Femoral vein transposition is one of the final resorts for vascular access in patients with exhaustion of upper limb venous patrimony and central venous occlusive disease. Its major pitfalls include hemodialysis access-induced distal ischemia and infection. Surgical procedures may be warranted to preserve vascular access if ischemia develops. Several techniques are reported in the literature for femoral vein transposition. CASE REPORT: We expose an endoscopic femoral vein harvesting as an alternative to the single thigh incision in order to avoid its associated complications. In the setting of ischemia, proximalization of arterial inflow was used to manage femoral vein transposition associated limb ischemia. CONCLUSION: This case report aims to expose the aforementioned unreported surgical techniques for lower limb arteriovenous fistula, its advantages, and pitfalls, as well as considerations on its future use.

Correlation Between Pedal Acceleration Time and Transcutaneous Oxygen Pressures - A Prognostic Tool for Wound Healing in the Diabetic Foot Population.

BACKGROUND: Pedal arch interrogation by ultrasound through systolic acceleration time measurement (Pedal Acceleration Time [PAT]) is a recently described technique that offers valuable insights into foot hemodynamics. Previous studies have demonstrated a correlation between PAT and the ankle-brachial index and PAT has been proposed as a prognostic tool for wound healing in patients with peripheral artery disease. This study aims to assess the correlation between PAT and Transcutaneous Pressure of Oxygen (TcPO2) in the diabetic foot population. METHODS: In this single-center cross-sectional study PAT and TcPO2 were measured in diabetic patients with ischemic foot ulcers. The assessment of wound status was performed between the 12th and 16th week after the first evaluation. The primary outcome was to assess the correlation between the values obtained for PAT and TcPO2. The secondary outcome was to establish a cut-off value for wound healing. RESULTS: Sixty limbs with ischemic foot ulcers were evaluated. The results showed a correlation between PAT and TcPO2 [F (1.52) = 16.928; R2 = 0.246; P < 0.001]. The receiver operating characteristics curve analysis showed an optimal cut-off value at PAT >186 ms for predicting a nonhealing ulcer with a 96% specificity (area under the curve = 0.774; confidence interval 0.648-0.872; P < 0.001). CONCLUSIONS: PAT showed a significant correlation with TcPO2 with high specificity to identify nonhealing foot ulcers due to insufficient foot perfusion with a potential prognostic value in the diabetic foot population.

Navigating complexity: The Supera's triumph in femoropopliteal lesions.

INTRODUCTION: The femoropopliteal sector endovascular treatment is particularly challenging due to its high tortuosity and torsional forces. Better results are still needed to ensure the long-term patency of stenting in this area. The Supera stent appears to change this paradigm. METHODS: This single-center retrospective cohort study aims to evaluate the efficacy and safety of femoropopliteal stenting with Supera in a real-world population. Seventy-nine patients were treated between January 2015 and December 2020, and the results are reported with a median follow-up of 28 months. RESULTS: Indications for revascularization were chronic limb-threatening ischemia with tissue loss (73.6%) or ischemic rest pain (17.7%) and claudication (7.6%). Thirty-six patients (45.6%) were classified as GLASS stage III according to the Global Limb Anatomic Staging System, with 65.8% and 30.4% in grades 3 and 4 of femoropopliteal and infrapopliteal sectors, respectively. The 36-month primary, primary-assisted, and secondary patency rates were 68.6%, 72.0%, and 79.0%, respectively, with an amputation-free survival rate of 86.6%. There was no significant difference between primary patency rates in GLASS stages I-II compared with GLASS stage III (36-month primary patency rates of 72% vs 63% respectively, p = 0.342) nor in amputation-free survival (88% vs 84%, p = 0.877). After adjusting for potential confounders, only the stent conformation significantly affected the primary patency rates, with a higher hazard of reintervention for the elongated (HR = 3.179; p = 0.36; CI 1.081-9.347) and the compressed (HR = 3.014; p = 0.42; CI 1.039-8.746) forms. CONCLUSIONS: The 36-month patency of the Supera stents in our real-world cohort was similar to other reported series. The GLASS stage did not interfere with the stent patency, proving it is a good choice even in the most adverse anatomy patients. Only the non-nominal stent conformation affected the primary patency rates in our patients.

Kidney autotransplantation as a key solution for a BEVAR type IIIb endoleak.

OBJECTIVES: Target vessel endoleaks are one of the most common causes of revision procedures after a fenestrated or branched endovascular aneurysm repair. Usually, a redo stenting is an effective therapy, however, not always feasible. We present a case of a hybrid treatment for a type IIIb endoleak using the renal autotransplantation technique. METHODS: A 60-year-old man with a thoracoabdominal aortic aneurysm has been treated with a custom-made branched endoprosthesis. Occlusion of the bridging stent to the right renal artery with total infarction of the right kidney was identified one week later and conservatively managed. After four years, a type IIIb endoleak was identified. Endovascular treatment was attempted unsuccessfully. So, the endoleak was corrected using a hybrid strategy with the kidney autotransplantation technique. RESULTS: A left kidney autotransplantation followed by an aortic stent-graft relining with a tubular graft has been done uneventfully, in a phased manner. Postoperative computed tomography angiography confirmed the patency of vascular reconstructions with no endoleaks. No adverse events occurred during one year of follow-up. CONCLUSION: Our case highlights kidney autotransplantation as a viable solution for a hybrid treatment of target vessel endoleaks and shows that this technique can assist complex endovascular aortic reconstructions.

Renal Autotransplantation for The Treatment of Renal Artery Aneurysm.

OBJECTIVE: Renal artery aneurysms are a rare condition; however, the rate of diagnosis has been increasing, because of the increasing use of complementary diagnostic methods. The best treatment strategy for RAAs remains controversial. Data on ex-vivo surgery associated with kidney autotransplantation are scarce. As a result, the goal of this study was to describe this technique and to report our results. METHODS: A retrospective monocentric study was undertaken using the clinical records and images of 35 patients diagnosed with renal artery aneurysm from 01/01/2010 to 31/12/2018. Indications for ex vivo surgery and autotransplantation were complex aneurysms with diameter >20 mm or rapid growth or symptomatic aneurysms or women wishing to become pregnant. Complex aneurysms were defined by anatomical criteria (bifurcation of the renal artery and its primary branches or hilar aneurysms) and/or physiological criteria (when time of warm ischemia in in-situ reconstruction is expected to last more than 45 minutes). The technique of ex-vivo surgery and autotransplantation consists of performing a nephrectomy, renal cooling, treatment of aneurysm in banking and implantation of the kidney in the homolateral iliac fossa. RESULTS: A total of 35 patients with 56 renal artery aneurysms (26 women, mean age 52.4 years-minimum and maximum 16 and 74 years) were included. Of these, 27 were treated by surgery and 8 were followed clinically. Among those treated surgically, 24 performed ex vivo surgery associated with autotransplantation. Regarding ex vivo surgery, nephrectomy was performed by laparoscopic surgery in 24 of the 27 surgeries, the mean surgical time was 5.3 hours, the median warm ischemia time was 4 minutes and the length of hospital stay was 12.2 days. Mortality was 0% and the kidney patency rate was 93% with a follow up of 47.2 months. Of the 17 patients with hypertension, 6 cured it, 4 improved and 7 maintained hypertension. CONCLUSION: Kidney autotransplantation appears to be efficient for most complex RAA with the possibility to minimize surgical aggression by performing laparoscopic nephrectomy.

Efficient Hardware Design and Implementation of the Voting Scheme-Based Convolution.

Due to a point cloud's sparse nature, a sparse convolution block design is necessary to deal with its particularities. Mechanisms adopted in computer vision have recently explored the advantages of data processing in more energy-efficient hardware, such as the FPGA, as a response to the need to run these algorithms on resource-constrained edge devices. However, implementing it in hardware has not been properly explored, resulting in a small number of studies aimed at analyzing the potential of sparse convolutions and their efficiency on resource-constrained hardware platforms. This article presents the design of a customizable hardware block for the voting convolution. We carried out an in-depth analysis to determine under which conditions the use of the voting scheme is justified instead of dense convolutions. The proposed hardware design achieves an energy consumption about 8.7 times lower than similar works in the literature by ignoring unnecessary arithmetic operations with null weights and leveraging data dependency. Access to data memory was also reduced to the minimum necessary, leading to improvements of around 55% in processing time. To evaluate both the performance and applicability of the proposed solution, the voting convolution was integrated into the well-known PointPillars model, where it achieves improvements between 23.05% and 80.44% without a significant effect on detection performance.

Customizable FPGA-Based Hardware Accelerator for Standard Convolution Processes Empowered with Quantization Applied to LiDAR Data.

In recent years there has been an increase in the number of research and developments in deep learning solutions for object detection applied to driverless vehicles. This application benefited from the growing trend felt in innovative perception solutions, such as LiDAR sensors. Currently, this is the preferred device to accomplish those tasks in autonomous vehicles. There is a broad variety of research works on models based on point clouds, standing out for being efficient and robust in their intended tasks, but they are also characterized by requiring point cloud processing times greater than the minimum required, given the risky nature of the application. This research work aims to provide a design and implementation of a hardware IP optimized for computing convolutions, rectified linear unit (ReLU), padding, and max pooling. This engine was designed to enable the configuration of features such as varying the size of the feature map, filter size, stride, number of inputs, number of filters, and the number of hardware resources required for a specific convolution. Performance results show that by resorting to parallelism and quantization approach, the proposed solution could reduce the amount of logical FPGA resources by 40 to 50%, enhancing the processing time by 50% while maintaining the deep learning operation accuracy.

Stimuli-Sensitive Self-Assembled Tubules Based on Lysine-Derived Surfactants for Delivery of Antimicrobial Proteins.

Drug delivery vectors based on amphiphiles have important features such as versatile physicochemical properties and stimuli-responsiveness. Amino acid-based surfactants are especially promising amphiphiles due to their enhanced biocompatibility compared to conventional surfactants. They can self-organize into micelles, vesicles and complex hierarchical structures, such as fibers, twisted and coiled ribbons, and tubules. In this work, we investigated the self-assembly and drug loading properties of a family of novel anionic double-tailed lysine-derived surfactants, with variable degree of tail length mismatch, designated as mLys10 and 10Lysn, where m and n are the number of carbon atoms in the tails. These surfactants form tubular aggregates with assorted morphologies in water that undergo gelation due to dense entanglement, as evidenced by light and electron microscopy. Lysozyme (LZM), an enzyme with antimicrobial properties, was selected as model protein for loading. After the characterization of the interfacial properties and phase behavior of the amphiphiles, the LZM-loading ability of the tubules was investigated, under varying experimental conditions, to assess the efficiency of the aggregates as pH- and temperature-sensitive nanocarriers. Further, the toxicological profile of the surfactants per se and surfactant/LZM hydrogels was obtained, using human skin fibroblasts (BJ-5ta cell line). Overall, the results show that the tubule-based hydrogels exhibit very interesting properties for the transport and controlled release of molecules of therapeutic interest.

Flow cytometric characterization of the saphenous veins endothelial cells in patients with chronic venous disease and in patients undergoing bypass surgery: an exploratory study.

Recent findings have suggested that the primary factors for development of chronic venous disease (CVD), which commonly manifests as varicose veins (VV), are due to structural and biochemical modifications of the vessel wall. The aim of this exploratory study was to characterize by flow cytometry the endothelial cells (EC) mechanically extracted from the varicose saphenous veins (VSV) segments of patients submitted to VV surgery, and to compare the expression of cell surface molecules in these EC with that observed in the EC from the graft SV (GSV) of patients undergoing bypass surgery. EC were isolated from distal- (varicose trunk) and from proximal- (nearly normal) VSV segments of 30 patients submitted to VV surgery, and from proximal GSV segments of 20 patients submitted to bypass surgery (control group), using a mechanical method, and their immunophenotype was characterized by flow cytometry. EC were identified as being CD45negCD146brightCD31bright, and analyzed for expression of activation-related (CD54, CD62E, CD106), procoagulant (CD142), and cell junction (CD31, CD146) molecules, and for the scavenger receptor, CD36. The EC harvested from the SV segments of CVD patients had lower expression of all the molecules evaluated, in comparison to controls; these differences were more evident for the EC isolated from the distal-VSV. The EC extracted from the proximal- and distal-VSV segments of the CVD patients also differ from each other, the first having lower levels of CD62E, CD106, CD142 and CD36. Groups did not match for gender and controls were heterogeneous concerning the underlying pathologies, which may have a confounding effect. Our study revealed that the EC isolated from varicose (distal) and nearly normal (proximal) VSV segments of the CVD patients differ phenotypically from each other, and from the EC of the control group. The VSV segments more affected by the CVD have the lowest expression of the studied markers. We hypothesize that CVD is associated with a decrease on the EC surface molecules, causing EC dysfunctionality. Further studies with a large number of gender-matched participants are needed, to confirm the results obtained in this exploratory study.

StemMapper: a curated gene expression database for stem cell lineage analysis.

Transcriptomic data have become a fundamental resource for stem cell (SC) biologists as well as for a wider research audience studying SC-related processes such as aging, embryonic development and prevalent diseases including cancer, diabetes and neurodegenerative diseases. Access and analysis of the growing amount of freely available transcriptomics datasets for SCs, however, are not trivial tasks. Here, we present StemMapper, a manually curated gene expression database and comprehensive resource for SC research, built on integrated data for different lineages of human and mouse SCs. It is based on careful selection, standardized processing and stringent quality control of relevant transcriptomics datasets to minimize artefacts, and includes currently over 960 transcriptomes covering a broad range of SC types. Each of the integrated datasets was individually inspected and manually curated. StemMapper's user-friendly interface enables fast querying, comparison, and interactive visualization of quality-controlled SC gene expression data in a comprehensive manner. A proof-of-principle analysis discovering novel putative astrocyte/neural SC lineage markers exemplifies the utility of the integrated data resource. We believe that StemMapper can open the way for new insights and advances in SC research by greatly simplifying the access and analysis of SC transcriptomic data. StemMapper is freely accessible at http://stemmapper.sysbiolab.eu.

FoxN1-dependent thymic epithelial cells promote T-cell leukemia development.

T-cell acute lymphoblastic leukemia (T-ALL) and T-lymphoblastic lymphomas (T-LBL) are aggressive malignancies of thymocytes. The role of thymic microenvironmental cells and stromal factors in thymocyte malignant transformation and T-ALL development remains little explored. Here, using the TEL-JAK2 transgenic (TJ2-Tg) mouse model of T-ALL/LBL, which is driven by constitutive JAK/STAT signaling and characterized by the acquisition of Notch1 mutations, we sought to identify stromal cell alterations associated with thymic leukemogenesis. Immunofluorescence analyses showed that thymic lymphomas presented epithelial areas characterized by keratin (Krt) 5 and Krt8 expression, adjacently to epithelial-free areas negative for Krt expression. Both areas contained abundant laminin (extracellular matrix) and ER-TR7+ (fibroblasts) CD31+ (endothelial) and CD11c+ (dendritic) cells. Besides Krt5, Krt-positive areas harbored medullary thymic epithelial cells (TECs) labeled by Ulex europaeus agglutinin-1. By performing flow cytometry and RNA sequencing analyses of thymic lymphomas, we observed an enrichment in medullary TEC markers in detriment of cortical TEC markers. To assess whether TECs are important for T-ALL/LBL development, we generated TJ2-Tg mice heterozygous for the FoxN1 transcription factor nude null mutation (Foxn1+/nu). Strikingly, in TJ2-Tg;Foxn1+/nu compound mice, both emergence of malignant cells in preleukemic thymi and overt T-ALL onset were significantly delayed. Moreover, in transplantation assays, leukemic cell expansion within the thymus of recipient Foxn1+/nu mice was reduced as compared with control littermates. Since thymopoesis is largely normal in Foxn1+/nu mice, these results indicate that FoxN1 haploinsufficiency in TECs has a more profound impact in thymic leukemogenesis.

Internal Carotid Artery Tortuosity as a Rare Cause of Dysphagia: Case Report and Literature Review.

Abnormalities in the morphology of internal carotid artery are commonly identified but their natural history is not well known. Rarely, vascular abnormalities can cause mass effect causing dysphagia. We report the case of a patient presenting with long-standing dysphagia and choking during swallowing of solid food caused by an internal carotid artery tortuosity undergoing surgical treatment at our institution and we review the available literature.

Status of research on physiology education in Brazil.

Physiology education research aims to investigate teaching-learning aspects and methods specifically applied to physiology teaching and learning. In this paper exploring Brazilian research public data and information from the Brazilian Physiological Society Teaching Committee, we investigated the status of this research topic (physiology education) in Brazil. The data showed that physiology education research needs to be more recognized and supported in Brazil, and more physiologists may become interested in research in this field. Thus this field will become more developed during the physiologists' education.

StemChecker: a web-based tool to discover and explore stemness signatures in gene sets.

Stem cells present unique regenerative abilities, offering great potential for treatment of prevalent pathologies such as diabetes, neurodegenerative and heart diseases. Various research groups dedicated significant effort to identify sets of genes-so-called stemness signatures-considered essential to define stem cells. However, their usage has been hindered by the lack of comprehensive resources and easy-to-use tools. For this we developed StemChecker, a novel stemness analysis tool, based on the curation of nearly fifty published stemness signatures defined by gene expression, RNAi screens, Transcription Factor (TF) binding sites, literature reviews and computational approaches. StemChecker allows researchers to explore the presence of stemness signatures in user-defined gene sets, without carrying-out lengthy literature curation or data processing. To assist in exploring underlying regulatory mechanisms, we collected over 80 target gene sets of TFs associated with pluri- or multipotency. StemChecker presents an intuitive graphical display, as well as detailed statistical results in table format, which helps revealing transcriptionally regulatory programs, indicating the putative involvement of stemness-associated processes in diseases like cancer. Overall, StemChecker substantially expands the available repertoire of online tools, designed to assist the stem cell biology, developmental biology, regenerative medicine and human disease research community. StemChecker is freely accessible at http://stemchecker.sysbiolab.eu.

Renal Autotransplantation - The Solution for Different Pathologies.

INTRODUCTION: Renal autotransplantation (RA) is a safe and effective procedure to reconstruct the urinary tract which first successful surgery was performed by Hardy in 1963. The main indications reported for performing RA generally includes renovascular disease, ureteral pathologies and neoplastic disease. RA may be also useful as the last recourse in preventing kidney loss in highly selected patients, especially when conventional methods have failed. METHODS: The authors pretend to describe four total different situations where the RA was the key solution for the pathology initially presented. RESULTS: 1- 52 years old male with a previous history of right nephrectomy that occurred during an exacerbation of his basal Chron disease so as left ureter cutaneostomie, presented with repetitive urinary tract infections that led to renal function impairment; 2- 57 years old female with the diagnosis of renal artery aneurysm while being studied as a potential renal donor; 3- 49 years old male admitted in the emergency room after a penetrating trauma which conditioned bowel and ureteral lesions with postoperative consecutive and recurrent peritoneal infections that compounded a necessity for a left ureter cutaneostomie, that the patient accurately refused; 4- 24 years old female with the diagnosis of Nutcracker syndrome identified after being studied regarding repetitive urgency admissions with frank hematuria. Every patient was submitted to RA. The intervention and postoperative course were uneventful. We performed an ultrasound evaluation on the day after each procedure to attest normal renal perfusion. CONCLUSION: The RA were realized in the two patients with ureteral lesions because there was no viable alternative but kidney loss. The other two clinical cases were treated with RA because they concerned a complex renovascular disease (one arterial and the other venous). Despite the existence of an endovascular option for these patients, long term follow up studies are still lacking. The RA is a viable option in specific situations for kidney salvage. The recent development of laparoscopic nephrectomy significantly decreased the surgical hostility to the patient and promoted the RA value on the treatment of complex vascular pathologies, traumatic disease and specific medical situations. It represents a credible alternative with attested results already described in the literature thus requiring a vast Institutional experience with conventional renal transplantation.

Antiphospholipid Syndrome and Acute Postpartum Limb Ischemia.

INTRODUCTION: The diagnosis of Antiphospholipid syndrome (APS) implies the identification of antiphospoholipid antibodies and arterial/venous thrombosis or pregnancy loss. During pregnancy, there is an increased risk of thrombotic complications. METHODS: Present a case of acute lower limb ischemia in a patient with APS during postpartum period Materials/ Methods: review of a clinical case and available literature Results: Patient diagnosed with APS (triple antibody positive and antecedent of 3 previous abortions) underwent cesarean at 29 weeks of gestation. She was medicated with aspirin 00mg/day and enoxaparin 60mg/day and had discharge on the second postoperative day. After 3 days she came to the emergency department with acute limb ischemia. AngioCT revealed thrombosis of the right iliac axis and pulmonary thromboembolism. Endovenous hypocoagulation with unfractionated heparin was immediately started. Due to the high thrombotic risk associated with any type of surgical intervention and improvement of ischemia with hypocoagulation, it was decided to postpone surgical revascularization. At the 10th day of hospitalization angioCT was repeated with maintenance of the iliac thrombosis and clinically the patient had severe claudication and ankle-arm index of 0.26. On the 16th day of hospitalization (after 5 plasmapheresis sessions), she was submitted to trans-femoral thrombectomy, with a good femoral pulse at the end of the procedure. On the 3rd postoperative day we detected pulse loss and angioCT confirmed re-thrombosis of the iliac axis and an oclusion of the popliteal artery. A new attempt at revascularization was made and a new transfemoral thrombectomy was performed, with immediate pulse recovery. We performed intraoperative angiography that confirmed occlusion of the popliteal artery and we proceeded trans-popliteal thrombectomy. Intraoperative control angiography revealed permeability of ilio- -femoro-popliteal axes with some defects of filling of the crural arteries (anterior tibial and peroneal arteries). After the procedure the patient become assymptomatic, with an ankle-arm index of 0.55 (with normal flow in femoral and popliteal artery but monophasyc flow in distal arteries) and had discharged medicated with aspirin, antivitaminik K and corticoid. CONCLUSION: The beneficial/risk of revascularization surgery should be well considered as well as the timing in which it should be performed. Plasmapheresis is important to minimize the thrombotic risk associated with the surgical procedure. Intra-operative angiography is essencial since arterial thrombosis can occur in several sectors, which can conditionate the success of revascularization procedure.