Circumferential Inferior Vena Cavectomy Without Caval Replacement in the Management of Renal Cell Carcinoma with Tumor Thrombus

PURPOSE OF REVIEW

Renal cell carcinoma presents a unique proclivity for vascular involvement giving rise to a peculiar form of locally advanced disease so-called tumor thrombus. To date, the only curative strategy for these cases remains surgery, which should aim to remove every vestige of macroscopic disease. Most of the preexisting literature advocates opening the vena cava to allow tumor thrombus removal and subsequent venous suture closure. However, inferior vena cava circumferential resection (cavectomy) without caval replacement is possible in the majority of cases since progressive occlusion facilitates the development of a collateral venous network aimed at maintaining cardiac preload.

RECENT FINDINGS

Radical nephrectomy with tumor thrombectomy remains a surgical challenge not exempt of operative complications even in experienced hands. In opposition to what traditional cavotomy and thrombus withdrawal can offer, circumferential cavectomy without caval replacement would provide comparable or even better oncologic control, decrease the likelihood of operative bleeding, and prevent the development of perioperative pulmonary embolism. This review focuses on the rationale of circumferential IVC resection without caval replacement and the important technical aspects of this approach in cases of renal cell carcinoma with vascular involvement. We also include an initial report on the surgical outcomes of a contemporary series of patients managed under this approach at our center.

Multidisciplinary virtual management of pulmonary nodules

INTRODUCTION AND OBJECTIVES

Multidisciplinary nodule clinics provide high-quality care and favor adherence to guidelines. Virtual care has shown savings benefits along with patient satisfaction. Our aim is to describe the first year of operation of a multidisciplinary virtual lung nodule clinic, the population evaluated and issued decisions. Secondarily, among discharged patients, we aimed to analyze their follow-up prior to the existence of our consultation, evaluating its adherence to guidelines.

MATERIALS AND METHODS

Observational study including all patients evaluated at the Virtual Lung Nodule Clinic (VLNC) (March 2018- March 2019). Clinical and radiological data were recorded. Recommendations, based on 2017 Fleischner Society guidelines, were categorized into follow-up, discharge or referral to lung cancer consultation. Discharged patients were classified according to adherence to guidelines of their previous management, into adequate, prolonged and non-indicated follow-up.

RESULTS

A total of 365 patients (58.9% men; median age 64.0 years) were included. Sixty-four percent had smoking history and 23% had chronic obstructive pulmonary disease (COPD). Most nodules were solid (87.4%) and multiple (57.5%). The median diameter was 6.00 mm. 43.8% of patients were discharged following first VLNC evaluation. Among them, 27.5% had received appropriate follow-up, but 66.9% had received poor management. Patients with prolonged follow-up (33.1%) were older (67.0 vs 60.5 years) and had larger nodules (6.00 mm vs 5.00). Non-indicated follow-up patients (33.8%) were more non-smokers (77.8% vs 31.8%) and presented smaller nodules (4.00 vs 5.00 mm).

CONCLUSIONS

During its first year of operation, the VLNC has evaluated a population with a relevant risk profile for lung cancer development, management of which should be cautious and adhere to guidelines. After the first VLNC assessment, approximately one-half of this population was discharged. It was noticeable that previous follow-up of discharged patients was found poorly adherent to guidelines, with a marked tendency to overmanagement.

Oral infectivity through carnivorism in murine model of Trypanosoma cruzi infection

Introduction

Oral transmission of T. cruzi is probably the most frequent transmission mechanism in wild animals. This observation led to the hypothesis that consuming raw or undercooked meat from animals infected with T. cruzi may be responsible for transmitting the infection. Therefore, the general objective of this study was to investigate host-pathogen interactions between the parasite and gastric mucosa and the role of meat consumption from infected animals in the oral transmission of T. cruzi.

Methods

Cell infectivity assays were performed on AGS cells in the presence or absence of mucin, and the roles of pepsin and acidic pH were determined. Moreover, groups of five female Balb/c mice were fed with muscle tissue obtained from mice in the acute phase of infection by the clone H510 C8C3hvir of T. cruzi, and the infection of the fed mice was monitored by a parasitemia curve. Similarly, we assessed the infective capacity of T. cruzi trypomastigotes and amastigotes by infecting groups of five mice Balb/c females, which were infected orally using a nasogastric probe, and the infection was monitored by a parasitemia curve. Finally, different trypomastigote and amastigote inoculums were used to determine their infective capacities. Adhesion assays of T. cruzi proteins to AGS stomach cells were performed, and the adhered proteins were detected by western blotting using monoclonal or polyclonal antibodies and by LC-MS/MS and bioinformatics analysis.

Results

Trypomastigote migration in the presence of mucin was reduced by approximately 30%, whereas in the presence of mucin and pepsin at pH 3.5, only a small proportion of parasites were able to migrate (∼6%). Similarly, the ability of TCTs to infect AGS cells in the presence of mucin is reduced by approximately 20%. In all cases, 60-100% of the animals were fed meat from mice infected in the acute phase or infected with trypomastigotes or amastigotes developed high parasitemia, and 80% died around day 40 post-infection. The adhesion assay showed that cruzipain is a molecule of trypomastigotes and amastigotes that binds to AGS cells. LC-MS/MS and bioinformatics analysis, also confirmed that transialidase, cysteine proteinases, and gp63 may be involved in TCTs attachment or invasion of human stomach cells because they can potentially interact with different proteins in the human stomach mucosa. In addition, several human gastric mucins have cysteine protease cleavage sites.

Discussion

Then, under our experimental conditions, consuming meat from infected animals in the acute phase allows the T. cruzi infection. Similarly, trypomastigotes and amastigotes could infect mice when administered orally, whereas cysteinyl proteinases and trans-sialidase appear to be relevant molecules in this infective process.

Soil properties determine the impact of nZVI on Lactuca sativa L and its rhizosphere

Nanoscale zero-valent iron (nZVI) is a promising material tool for the remediation of metal(loid)-contaminated soils since it reduces metal(loid) availability and plant uptake, thereby enhancing the development of the plants. However, the effects of nZVI as nanoparticles on soil properties, plants, and the microbial rhizosphere in unpolluted soils are poorly understood. Here we tested the impact of nZVI at different doses (0.5 and 5% of commercial suspension) on soil properties, lettuce plants, and their microbial rhizosphere in two non-contaminated soils with distinct physico-chemical properties (alkaline versus acidic soil). To this end, a pot experiment was performed with lettuce plants in a growth chamber for a month. Both soils showed an increase in of pH and available Fe after nZVI application. However, these effects were more marked in the acidic soil. In this regard, the plants in this soil showed increased biomass and Fe content. TEM analysis revealed that although the roots and leaves of plants grown in the alkaline soil showed better cell integrity than those in acidic soil-an observation that was consistent with the visual appearance of the plants-the former were more affected by the nZVI treatment. Regarding the microbial rhizosphere, in general, nZVI enhanced enzyme activity regardless of the soil type. Microbial functional diversity showed a significant decline in response to nZVI in alkaline soil. In contrast, the 0.5% nZVI treatment had a positive effect on this parameter in acidic soil. Bacterial genetic diversity was less affected by the presence of nZVI than fungal diversity, which was higher in nZVI-treated acidic soils. In addition, alterations of bacterial and fungal communities were associated with available Fe in acidic soil. In conclusion, soil properties play a key role in determining the effects of nZVI on lettuce plants and their rhizosphere.

A Dye Uptake Assay to Measure Large-Pore Channel Activity in Trypanosoma cruzi

Large-pore channels allow the exchange of ions and molecules between the intra- and extracellular compartments. These channels are structures formed by several protein families with little or no evolutionary linkages that include connexins (Cxs), pannexins (Panxs), innexins (Inxs), CALHM1, and LRRC8 proteins. Recently, we have described the unnexins (Unxs) proteins expressed in Trypanosoma cruzi (T. cruzi) that also is like to form large-pore channels at the plasma membrane. In this chapter, we describe a dye uptake method for evaluating the unnexin-formed channel function in T. cruzi, as well as the methods for evaluating their participation in the transformation of trypomastigotes into amastigotes. These methods can facilitate understanding the role of large-pore channels in the parasite's biology.

Effect of acute on chronic liver failure over post-transplant survival

INTRODUCTION AND OBJECTIVES

Acute-on-chronic liver failure (ACLF) is associated with reduced short-term survival, and liver transplantation is frequently the only therapeutic option. Nonetheless, the post-transplantation prognosis seems to be worse in ACLF patients.

MATERIALS AND METHODS

The databases of two university centers were retrospectively evaluated, and adult patients with cirrhosis who underwent transplantation between 2013 and 2020 were included. One-year survival of patients with ACLF was compared to that of patients without ACLF. Variables associated with mortality were identified.

RESULTS

A total of 428 patients were evaluated, and 303 met the inclusion criteria; 57.1% were male, the mean age was 57.1 ± 10.2 years, 75 patients had ACLF, and 228 did not. The main etiologies of ACLF were NASH (36.6%), alcoholic liver disease (13.9%), primary biliary cholangitis (8.6%) and autoimmune hepatitis (7.9%). Mechanical ventilation, renal replacement therapy, the use of vasopressors and the requirement of blood product transfusion during liver transplantation were significantly more frequent in ACLF patients. Among those recipients without and with ACLF, survival at 1, 3 and 5 years was 91.2% vs. 74.7%, 89.1% vs. 72.6% and 88.3% vs. 72.6%, respectively (p=0.001). Among pre-transplantation variables, only the presence of ACLF was independently associated with survival (HR 3.2, 95% CI: 1.46-7.11). Post-transplantation variables independently associated with survival were renal replacement therapy (HR 2.8, 95% CI: 1.1-6.8) and fungal infections (HR 3.26, 95% CI: 1.07-9.9).

CONCLUSIONS

ACLF is an independent predictor of one-year post-transplantation survival. Importantly, transplant recipients with ACLF require the use of more resources than patients without ACLF.

Unnexin is a protein subunit of a large-pore channel expressed by unicellular organisms

Cells of vertebrate and invertebrate organisms express proteins specialized in membrane channel-based cell-cell communication that are absent in unicellular organisms. We recently described the prediction of some members of the large-pore channel family in kinetoplastids, consisting of proteins called unnexins, which share several structural features with innexin and pannexin proteins. Here, we demonstrated that the unnexin1 protein (Unx1) is delivered to the cell membrane, displaying a topology consisting of four transmembrane domains with C and N termini on the cytoplasmic side and form large-pore channels that are permeable to small molecules. Low extracellular Ca2+/Mg2+ levels or extracellular alkalinization, but not mechanical stretching, increases channel activity. The Unx1 channel mediates the influx of Ca2+ and does not form intercellular dye coupling between HeLa Unx1 transfected cells. Unx1 channel function was further evidenced by its ability to mediate ionic currents when expressed in Xenopus oocytes. Downregulation of Unx1 mRNA with morpholine contains Trypanosoma cruzi invasion. Phylogenetic analysis revealed the presence of Unx1 homologs in other protozoan parasites, suggesting a conserved function for these channel parasites in other protists. Our data demonstrate that Unx1 forms large-pore membrane channels, which may serve as a diffusional pathway for ions and small molecules that are likely to be metabolic substrates or waste products, and signaling autocrine and paracrine molecules that could be involved in cell invasion. As morpholinos-induced downregulation of Unx1 reduces the infectivity of trypomastigotes, the Unx1 channels might be an attractive target for developing trypanocide drugs.

Challenges and perspectives in research and teaching of host pathogen interaction topics: new post-pandemic times to Brazil and other South American countries

Here is our proposal to improve learning in biomedical sciences for graduate and undergraduate courses with a broad vision integrating disciplines such as molecular cell biology, biochemistry, and biophysics around concepts of pathogen interaction within vertebrate and invertebrate hosts. Our paradigm is based on the possibility offered by the pandemic to have remote activities that give access to students and researchers from different places in Brazil and Latin American countries to discuss science. A multidisciplinary view of host-pathogen interaction allows us to understand better the mechanisms involved in the pathology of diseases, as well as to formulate broad strategies for the diagnosis, treatment, and control of thereof. The approach to integrating heterogeneous groups in science involves the critical analysis of national scientific resource distribution, where only some have the possibilities to conduct competitive scientific research. Solid theoretical training, contact, collaboration with groups of excellence, and training within a multidisciplinary network are our proposals for a permanent platform of scientific strengthening and dissemination for Latin America. Here we will review the concept of host-pathogen interaction, the type of institutions where it is taught and researched, new trends in active teaching methodologies, and the current political context in science.

Influence of H-bonds on the photoionization of aromatic chromophores in water: The aniline molecule

We have conducted time-resolved experiments (pump-probe and pump-repump-probe) on a model aromatic chromophore, aniline, after excitation in water at 267 nm. In the initial spectra recorded, in addition to the absorption corresponding to the bright ππ* excitation, the fingerprint of a transient state with the electron located on the solvent molecule is identified. We postulate that the latter corresponds to the πσ* state along the N-H bond, whose complete relaxation with a ∼500 ps lifetime results in the formation of the fully solvated electron and cation. This ionization process occurs in parallel with the ππ* photophysical channel that yields the characteristic ∼1 ns fluorescence lifetime. The observed branched pathway is rationalized in terms of the different H-bonds that the water establishes with the amino group. The proposed mechanism could be common for aromatics in water containing N-H or O-H bonds and would allow the formation of separated charges after excitation at the threshold of their electronic absorptions.

Ising superconductivity induced from spin-selective valley symmetry breaking in twisted trilayer graphene

We show that the e-e interaction induces a strong breakdown of valley symmetry for each spin channel in twisted trilayer graphene, leading to a ground state where the two spin projections have opposite sign of the valley symmetry breaking order parameter. This leads to a spin-valley locking in which the electrons of a Cooper pair are forced to live on different Fermi lines attached to opposite valleys. Furthermore, we find an effective intrinsic spin-orbit coupling explaining the protection of the superconductivity against in-plane magnetic fields. The effect of spin-selective valley symmetry breaking is validated as it reproduces the experimental observation of the reset of the Hall density at 2-hole doping. It also implies a breakdown of the symmetry of the bands from C₆ to C₃, with an enhancement of the anisotropy of the Fermi lines which is at the origin of a Kohn-Luttinger (pairing) instability. The isotropy of the bands is gradually recovered, however, when the Fermi level approaches the bottom of the second valence band, explaining why the superconductivity fades away in the doping range beyond 3 holes per moiré unit cell in twisted trilayer graphene.

Distributional regression modeling via generalized additive models for location, scale, and shape: An overview through a data set from learning analytics

The advent of technological developments is allowing to gather large amounts of data in several research fields. Learning analytics (LA)/educational data mining has access to big observational unstructured data captured from educational settings and relies mostly on unsupervised machine learning (ML) algorithms to make sense of such type of data. Generalized additive models for location, scale, and shape (GAMLSS) are a supervised statistical learning framework that allows modeling all the parameters of the distribution of the response variable with respect to the explanatory variables. This article overviews the power and flexibility of GAMLSS in relation to some ML techniques. Also, GAMLSS' capability to be tailored toward causality via causal regularization is briefly commented. This overview is illustrated via a data set from the field of LA. This article is categorized under:Application Areas > Education and LearningAlgorithmic Development > StatisticsTechnologies > Machine Learning.

Trypanosoma cruzi pathogenicity involves virulence factor expression and upregulation of bioenergetic and biosynthetic pathways

The molecular repertoire of Trypanosoma cruzi effects its virulence and impacts the clinical course of the resulting Chagas disease. This study aimed to determine the mechanism underlying the pathogenicity of T. cruzi. Two T. cruzi cell lines (C8C3hvir and C8C3lvir), obtained from the clone H510 C8C3 and exhibiting different virulence phenotypes, were used to evaluate the parasite's infectivity in mice. The organ parasite load was analysed by qPCR. The proteomes of both T. cruzi cell lines were compared using nLC-MS/MS. Cruzipain (Czp), complement regulatory protein (CRP), trans-sialidase (TS), Tc-85, and sialylated epitope expression levels were evaluated by immunoblotting. High-virulence C8C3hvir was highly infectious in mice and demonstrated three to five times higher infectivity in mouse myocardial cells than low-virulence C8C3lvir. qPCR revealed higher parasite loads in organs of acute as well as chronically C8C3hvir-infected mice than in those of C8C3lvir-infected mice. Comparative quantitative proteomics revealed that 390 of 1547 identified proteins were differentially regulated in C8C3hvir with respect to C8C3lvir. Amongst these, 174 proteins were upregulated in C8C3hvir and 216 were downregulated in C8C3lvir. The upregulated proteins in C8C3hvir were associated with the tricarboxylic acid cycle, ribosomal proteins, and redoxins. Higher levels of Czp, CRP, TS, Tc-85, and sialylated epitopes were expressed in C8C3hvir than in C8C3lvir. Thus, T. cruzi virulence may be related to virulence factor expression as well as upregulation of bioenergetic and biosynthetic pathways proteins.

Application of machine learning to predict aneuploidy and mosaicism in embryos from in vitro fertilization (IVF) cycles

BACKGROUND

OBJECTIVE

STUDY DESIGN

RESULTS

CONCLUSION

Assessment of Noninvasive Markers of Steatosis and Liver Fibrosis in HIV-monoinfected Patients on Stable Antiretroviral Regimens

Background

Nonalcoholic fatty liver disease (NAFLD) is a major nonacquired immune deficiency syndrome-defining condition for persons with human immunodeficiency virus (PWH). We aimed to validate noninvasive tests for the diagnosis of NAFLD in PWH.

Methods

This is a cross-sectional study of PWH on stable antiretroviral therapy with persistently elevated transaminases and no known liver disease. The area under the receiver operating characteristic curve (AUROC) was calculated to compare the diagnostic accuracy of liver biopsy with abdominal ultrasound, transient elastography (TE) (including controlled attenuation parameter [CAP]), and noninvasive markers of steatosis (triglyceride and glucose index [TyG], hepatic steatosis index [HSI], fatty liver index [FLI]) and fibrosis ([FIB]-4, aminotransferase-to-platelet ratio index [APRI], NAFLD fibrosis score). We developed a diagnostic algorithm with serial combinations of markers.

Results

Of 146 patients with increased transaminase levels, 69 underwent liver biopsy (90% steatosis, 61% steatohepatitis, and 4% F ≥3). The AUROC for steatosis was as follows: ultrasound, 0.90 (0.75–1); CAP, 0.94 (0.88–1); FLI, 0.81 (0.58–1); HSI, 0.74 (0.62–0.87); and TyG, 0.75 (0.49–1). For liver fibrosis ≥F3, the AUROC for TE, APRI, FIB-4, and NAFLD fibrosis score was 0.92 (0.82–1), 0.96 (0.90–1), 0.97 (0.93–1), and 0.85 (0.68–1). Optimal diagnostic performance for liver steatosis was for 2 noninvasive combined models of tests with TyG and FLI/HSI as the first tests and ultrasound or CAP as the second tests: AUROC = 0.99 (0.97–1, P < .001) and 0.92 (0.77–1, P < .001).

Conclusions

Ultrasound and CAP performed best in diagnosing liver steatosis, and FLI, TyG, and HSI performed well. We propose an easy-to-implement algorithm with TyG or FLI as the first test and ultrasound or CAP as the second test to accurately diagnose or exclude NAFLD.

Humoral and cellular immune memory response 12 years following single dose vaccination against hepatitis A in Argentinian children

Infants' universal hepatitis A virus (HAV) single-dose vaccination has been highly effective for controlling HAV infection in Argentina, and in other Latin-American countries that adopted that strategy. Although antibodies wane over time, this has not been associated with HAV outbreaks or breakthrough infections, suggesting a relevant role for memory immunity. This study assessed long term humoral and cellular immune memory response after an average of 12 years follow-up of HAV single-dose vaccination. We selected 81 HAV-single dose vaccinated individuals from a 2015 study, including 54 with unprotective (UAL) and 27 with protective antibody levels (PAL) against HAV. Humoral memory response was assessed by measuring anti-HAV antibody titers at admission in both groups, and 30 days after a booster dose in the UAL group. Flow cytometry analysis of peripheral blood mononuclear cell samples stimulated with HAV antigen was performed in 47/81 individuals (21 with PAL, 26 with UAL) to identify activated CD4 + memory T cells or CD8 + memory T cells. The results showed that 48/52 (92%) individuals from UAL group who completed follow up reached protective levels after booster dose. In the PAL group, anti-HAV Abs waned in 2/27 (7%) individuals lacking seroprotection, while in 25/27 (93%) Abs remained >10 mUI/mL. HAV-specific memory CD4 + T cells were detected in 25/47 (53.2%) subjects while HAV-specific memory CD8 + T cells were observed in 16/47 (34.04%) individuals. HAV-specific memory CD4⁺ and CD8⁺ T cell responses were detected in 11/21 (52.4%) and in 9/21 (42.9%) subjects with PAL and in 14/26 (53.8%) and in 7/26 (26.9%) individuals with UAL, showing that the presence of memory T-cells was independent of the level or presence of anti-HAV antibodies. Long-term immunity demonstrated in the present work, including or not antibody persistence, suggests that individuals with waned Ab titers may still be protected and supports the single-dose HAV strategy.

Unnexins: Homologs of innexin proteins in Trypanosomatidae parasites

Large-pore channels, including those formed by connexin, pannexin, innexin proteins, are part of a broad family of plasma membrane channels found in vertebrates and invertebrates, which share topology features. Despite their relevance in parasitic diseases such as Chagas and malaria, it was unknown whether these large-pore channels are present in unicellular organisms. We identified 14 putative proteins in Trypanosomatidae parasites as presumptive homologs of innexin proteins. All proteins possess the canonical motif of the innexin family, a pentapeptide YYQWV, and 10 of them share a classical membrane topology of large-pore channels. A sequence similarity network analysis confirmed their closeness to innexin proteins. A bioinformatic model showed that a homolog of Trypanosoma cruzi (T. cruzi) could presumptively form a stable octamer channel with a highly positive electrostatic potential in the internal cavities and extracellular entrance due to the notable predominance of residues such as Arg or Lys. In vitro dye uptake assays showed that divalent cations-free solution increases YO-PRO-1 uptake and hyperosmotic stress increases DAPI uptake in epimastigotes of T. cruzi. Those effects were sensitive to probenecid. Furthermore, probenecid reduced the proliferation and transformation of T. cruzi. Moreover, probenecid or carbenoxolone increased the parasite sensitivity to antiparasitic drugs commonly used in therapy against Chagas. Our study suggests the existence of innexin homologs in unicellular organisms, which could be protein subunits of new large-pore channels in unicellular organisms.

Demodex folliculorum (Trombidiformes: Demodicidae) and Demodex brevis Prevalence in an Extreme Environment of Chile

The prevalence of mites of the genus Demodex and their associations with host age, gender, workplace, and comorbid skin and ocular conditions were studied in participants in Antofagasta, Chile, which is in a region with an extreme environment. We examined 680 participants aged 18-88 yr using standardized surface skin biopsies. Among them, Demodex had a prevalence of 13.5 % (95% confidence interval, 10.88-16.17). A slightly higher prevalence was observed in males (51.1%; 95% confidence interval, 40.9-61.3; nonsignificant) and participants in the 69-88 yr age group (50.0%; 95% confidence interval, 23.8-76.2; P < 0.05). Regarding the species involved, Demodex folliculorum was found in 89.1% (CI 82.7-95.5) of cases, while D. brevis was found in the remaining 10.9% of cases. A higher prevalence (25.0% CI 16.1-33.91) was observed in participants who worked indoors in generally enclosed and dust-rich environments (such as theaters, libraries, and administrative offices). There was also a strong association between Demodex prevalence and conjunctival hyperemia, with 35.9% (95% confidence interval, 9.1-35; OR 17.9) of the Demodex positive participants having this pathology compared to 10.3% of the noninfested participants. In summary, the prevalence of Demodex in Antofagasta, Chile (13.5%) was toward the lower end of the range reported among other regions around the world. Environmental factors such as exposure to the sun (including ultraviolet rays) or environmental pollution may affect the mites. In addition, Demodex genetics (related to virulence) and the ocular or skin microbiota may positively or negatively influence infestation and pathology.

Retrohepatic inferior vena cava control through an anterior approach in cases of renal cell carcinoma with level IIIa tumor thrombus: Step-by-step description

OBJECTIVE

To evaluate the safety and efficacy of the retrohepatic inferior vena cava control through an anterior approach (RIVCA) technique in renal cell carcinoma (RCC) with level IIIa tumor thrombus.

PATIENTS AND METHODS

Initial series of 6 cases presenting RCC and level IIIa tumor thrombus who underwent radical nephrectomy and tumor thrombectomy using the RIVCA technique between 2018-2019. RIVCA technique aims to gain complete control of the retrohepatic inferior vena cava above the cranial end of the tumor thrombus, but excluding the major hepatic veins in order to preserve the natural hepato-caval shunt. A step-by-step description of the procedure is provided. Disease features, operative characteristics, and surgical outcomes were registered prospectively.

RESULTS

Radical nephrectomy and tumor thrombectomy were completed in all cases. RIVCA technique did not increase operative time significantly (range: 14-22 min). Mean estimated blood loss was 325 cc (range: 250-400). Blood transfusion was not required intraoperatively in any of the cases. Mean postoperative transfusion rate was 1.3 red blood cells packed units (range: 0-2). There were no cases of intraoperative pulmonary embolism or major complications (Clavien-Dindo III-V) in the period of 30 days postoperatively. Median postoperative length of stay was 8 days (range: 5-11).

CONCLUSIONS

The RIVCA technique applied to cases of RCC and level IIIa tumor thrombus provides complete control of the retrohepatic inferior vena cava above the tumor thrombus cranial end, while prevents intraoperative hemodynamic instability by maintaining cardiac preload through the porto-caval shunt. This technique may limit operative morbidity (intraoperative pulmonary embolism and massive hemorrhage), thus becoming a helpful adjunct to be used in cases of RCC with level IIIa tumor thrombus.

O-203 Application of machine learning to predict aneuploidy and mosaicism in embryos from in vitro fertilization (IVF) cycles

Study question

Is it possible to predict the likelihood of an IVF embryo being aneuploid and/or mosaic using a machine learning algorithm?

Summary answer

There are paternal, maternal, embryonic and IVF-cycle factors that are associated with embryonic chromosomal status that can be used as predictors in machine learning models.

What is known already

The factors associated with embryonic aneuploidy have been extensively studied. Mostly maternal age and to a lesser extent male factor and ovarian stimulation have been related to the occurrence of chromosomal alterations in the embryo.

On the other hand, the main factors that may increase the incidence of embryo mosaicism have not yet been established.

The models obtained using classical statistical methods to predict embryonic aneuploidy and mosaicism are not of high reliability. As an alternative to traditional methods, different machine and deep learning algorithms are being used to generate predictive models in different areas of medicine, including human reproduction.

Study design, size, duration

The study design is observational and retrospective. A total of 4654 embryos from 1558 PGT-A cycles were included (January-2017 to December-2020). The trophoectoderm biopsies on D5, D6 or D7 blastocysts were analysed by NGS. Embryos with ≤25% aneuploid cells were considered euploid, between 25-50% were classified as mosaic and aneuploid with &gt;50%.

The variables of the PGT-A were recorded in a database from which predictive models of embryonic aneuploidy and mosaicism were developed.

Participants/materials, setting, methods

The main indications for PGT-A were advanced maternal age, abnormal sperm FISH and recurrent miscarriage or implantation failure. Embryo analysis were performed using Veriseq-NGS (Illumina).

The software used to carry out all the analysis was R (RStudio). The library used to implement the different algorithms was caret. In the machine learning models, 22 predictor variables were introduced, which can be classified into 4 categories: maternal, paternal, embryonic and those specific to the IVF cycle.

Main results and the role of chance

The different couple, embryo and stimulation cycle variables were recorded in a database (22 predictor variables). Two different predictive models were performed, one for aneuploidy and the other for mosaicism. The predictor variable was of multi-class type since it included the segmental and whole chromosome alteration categories.

The dataframe were first preprocessed and the different classes to be predicted were balanced. A 80% of the data were used for training the model and 20% were reserved for further testing. The classification algorithms applied include multinomial regression, neural networks, support vector machines, neighborhood-based methods, classification trees, gradient boosting, ensemble methods, Bayesian and discriminant analysis-based methods. The algorithms were optimized by minimizing the Log_Loss that measures accuracy but penalizing misclassifications.

The best predictive models were achieved with the XG-Boost and random forest algorithms. The AUC of the predictive model

for aneuploidy was 80.8% (Log_Loss

1.028) and for mosaicism 84.1% (Log_Loss: 0.929). The best predictor variables of the models were maternal age, embryo quality, day of biopsy and whether or not the couple had a history of pregnancies with chromosomopathies. The male factor only played a relevant role in the mosaicism model but not in the aneuploidy model.

Limitations, reasons for caution

Although the predictive models obtained can be very useful to know the probabilities of achieving euploid embryos in an IVF cycle, increasing the sample size and including additional variables could improve the models and thus increase their predictive capacity.

Wider implications of the findings

Machine learning can be a very useful tool in reproductive medicine since it can allow the determination of factors associated with embryonic aneuploidies and mosaicism in order to establish a predictive model for both. To identify couples at risk of embryo aneuploidy/mosaicism could benefit them of the use of PGT-A.

Trial registration number

Not Applicable

Retrohepatic inferior vena cava control through an anterior approach in cases of renal cell carcinoma with level iiia tumor thrombus: Step-by-step description

OBJECTIVE

To evaluate the safety and efficacy of the retrohepatic inferior vena cava control through an anterior approach (RIVCA) technique in renal cell carcinoma (RCC) with level iiia tumor thrombus.

PATIENTS AND METHODS

Initial series of 6 cases presenting RCC and level iiia tumor thrombus who underwent radical nephrectomy and tumor thrombectomy using the RIVCA technique between 2018-2019. RIVCA technique aims to gain complete control of the retrohepatic inferior vena cava above the cranial end of the tumor thrombus, but excluding the major hepatic veins in order to preserve the natural hepato-caval shunt. A step-by-step description of the procedure is provided. Disease features, operative characteristics, and surgical outcomes were registered prospectively.

RESULTS

Radical nephrectomy and tumor thrombectomy were completed in all cases. RIVCA technique did not increase operative time significantly (range: 14-22min). Mean estimated blood loss was 325cc (range: 250-400). Blood transfusion was not required intraoperatively in any of the cases. Mean postoperative transfusion rate was 1.3 red blood cells packed units (range: 0-2). There were no cases of intraoperative pulmonary embolism or major complications (Clavien-Dindo III-V) in the period of 30 days postoperatively. Median postoperative length of stay was 8 days (range: 5-11).

CONCLUSIONS

The RIVCA technique applied to cases of RCC and level iiia tumor thrombus provides complete control of the retrohepatic inferior vena cava above the tumor thrombus cranial end, while prevents intraoperative hemodynamic instability by maintaining cardiac preload through the porto-caval shunt. This technique may limit operative morbidity (intraoperative pulmonary embolism and massive hemorrhage), thus becoming a helpful adjunct to be used in cases of RCC with level iiia tumor thrombus.

Seasonal Dynamics of Fleas (Siphonaptera: Pulicidae, Ceratophyllidae and Leptopsyllidae) on Oryctolagus cuniculus in a Meso-Mediterranean Area of Central Spain

Flea infestations of wild rabbits were examined monthly in central Spain in a meso-Mediterranean area for 5 yr. A total of 1,180 wild rabbits were trapped and 7,022 fleas were collected from them. Overall, the prevalence was 74.1% with a mean flea index of 5.95 fleas per rabbit. Four flea species were identified: Spilopsyllus cuniculi (Dale, 1878) was the most abundant species (accounting for 74.3% of fleas collected) followed by Xenopsylla cunicularis (Smit, 1957), Odontopsyllus quirosi (Gil Collado, 1934), and Nosopsyllus fasciatus (Bosc, 1800) (18.9, 6.7, and 0.1%, respectively). The highest prevalence was observed in S. cuniculi (48.6%) followed by X. cunicularis, O. quirosi, and N. fasciatus (34.3, 20.0, and 0.6%, respectively). Odontopsyllus quirosi and S. cuniculi were mainly collected from autumn to spring with the peak of infestation in winter, while X. cunicularis was mainly found from spring to autumn with maximum levels of infestation during the summer months. The relevance of these findings is discussed.

Risk factors, management, and survival of bladder cancer after kidney transplantation

INTRODUCTION AND OBJECTIVES

Kidney transplantation is associated with an increased risk of bladder cancer; however guidelines have not been established on the management of bladder cancer after kidney transplantation.

MATERIALS AND METHODS

A systematic literature review using PubMed was performed in accordance with the PRISMA statement to identify studies concerning the prevalence and survival of bladder cancer after kidney transplantation. The risk factors and management of bladder cancer after kidney transplantation were also reviewed and discussed.

RESULTS

A total of 41 studies, published between 1996 and 2018, reporting primary data on bladder cancer after kidney transplantation were identified. Marked heterogeneity in bladder cancer prevalence, time to diagnosis, non-muscle invasive/muscle-invasive bladder cancer prevalence, and survival was noted. Four studies, published between 2003 and 2017, reporting primary data on bladder cancer treated with Bacillus Calmette-Guérin (BCG) after kidney transplantation were identified. Disease-free survival, cancer-specific survival, and overall survival were similar between BCG studies (75-100%).

CONCLUSIONS

Carcinogen exposure that led to ESRD, BKV, HPV, immunosuppressive agents, and the immunosuppressed state likely contribute to the increased risk of bladder cancer after renal transplantation. Non-muscle invasive disease should be treated with transurethral resection. BCG can be safely used in transplant recipients and likely improves the disease course. Muscle-invasive disease should be treated with radical cystectomy, with special consideration to the dissection and urinary diversion choice. Chemotherapy and immune checkpoint inhibitors can be safely used in regionally advanced bladder cancer with potential benefit. mTOR inhibitors may reduce the risk of developing bladder cancer, and immunosuppression medications should be reduced if malignancy develops.

Structural, vibrational and electronic properties of α'-Ga2S3 under compression

We report a joint experimental and theoretical study of the low-pressure phase of α'-Ga₂S₃ under compression. Theoretical ab initio calculations have been compared to X-ray diffraction and Raman scattering measurements under high pressure carried out up to 17.5 and 16.1 GPa, respectively. In addition, we report Raman scattering measurements of α'-Ga₂S₃ at high temperature that have allowed us to study its anharmonic properties. To understand better the compression of this compound, we have evaluated the topological properties of the electron density, the electron localization function, and the electronic properties as a function of pressure. As a result, we shed light on the role of the Ga-S bonds, the van der Waals interactions inside the channels of the crystalline structure, and the single and double lone electron pairs of the sulphur atoms in the anisotropic compression of α'-Ga₂S₃. We found that the structural channels are responsible for the anisotropic properties of α'-Ga₂S₃ and the A'(6) phonon, known as the breathing mode and associated with these channels, exhibits the highest anharmonic behaviour. Finally, we report calculations of the electronic band structure of α'-Ga₂S₃ at different pressures and find a nonlinear pressure behaviour of the direct band gap and a pressure-induced direct-to-indirect band gap crossover that is similar to the behaviour previously reported in other ordered-vacancy compounds, including β-Ga₂Se₃. The importance of the single and, more specially, the double lone electron pairs of sulphur in the pressure dependence of the topmost valence band of α'-Ga₂S₃ is stressed.

Phylogeography and evolutionary history of hepatitis E virus genotype 3 in Argentina

BACKGROUND

Few studies about the evolutionary history of the hepatitis E virus (HEV) have been conducted. The aim of our work was to investigate and make inferences about the origin and routes of dispersion of HEV-3 in Argentina.

METHODS

Phylogenetic, coalescent and phylogeographic analyses were performed using a 322-bp ORF2 genomic fragment of all HEV-3 sequences with known date and place of isolation published at GenBank until May 2018 (n=926), including 16 Argentinian sequences (isolated from pigs, water and humans).

RESULTS

Phylogenetic analysis revealed two clades within HEV-3: abchij and efg. All Argentinian samples were grouped intermingled within clade 3abchij. The coalescent analysis showed that the most recent common ancestor for the clade 3abchij would have existed around the year 1967 (95% highest posterior density (HPD): 1963-1970). The estimated substitution rate was 1.01×10-2 (95%HPD: 9.3×10-3-1.09×10-2) substitutions/site/y, comparable with the rate previously described. The phylogeographic approach revealed a correspondence between phylogeny and place of origin for Argentinian samples, suggesting many HEV introductions in the country, probably from Europe and Japan.

CONCLUSIONS

This is the first evolutionary inference of HEV-3 that includes Argentinian strains, showing the circulation of many HEV-3 subtypes, obtained from different sources and places, with recent diversification processes.

ACCESSION NUMBERS

[KX812460], [KX812461], [KX812462], [KX812465], [KX812466], [KX812467], [KX812468], [KX812469].

Immune Modulation by Inhibitors of the HO System

The heme oxygenase (HO) system involves three isoforms of this enzyme, HO-1, HO-2, and HO-3. The three of them display the same catalytic activity, oxidating the heme group to produce biliverdin, ferrous iron, and carbon monoxide (CO). HO-1 is the isoform most widely studied in proinflammatory diseases because treatments that overexpress this enzyme promote the generation of anti-inflammatory products. However, neonatal jaundice (hyperbilirubinemia) derived from HO overexpression led to the development of inhibitors, such as those based on metaloproto- and meso-porphyrins inhibitors with competitive activity. Further, non-competitive inhibitors have also been identified, such as synthetic and natural imidazole-dioxolane-based, small synthetic molecules, inhibitors of the enzyme regulation pathway, and genetic engineering using iRNA or CRISPR cas9. Despite most of the applications of the HO inhibitors being related to metabolic diseases, the beneficial effects of these molecules in immune-mediated diseases have also emerged. Different medical implications, including cancer, Alzheimer´s disease, and infections, are discussed in this article and as to how the selective inhibition of HO isoforms may contribute to the treatment of these ailments.

Relationship between IgA1 lectin-binding specificities, mesangial C4d deposits and clinical phenotypes in IgA nephropathy

BACKGROUND AND OBJECTIVES

The reason why mesangial C4d deposits are detected in only certain biopsies of IgA nephropathy remains unclear. We analyse the association between IgA glycosylation patterns, mesangial C4 deposition and clinical phenotypes in IgA nephropathy.Design, setting, participants and measurements: This cross-sectional study included 145 patients with idiopathic IgA nephropathy. We measured the serum levels of three different IgA1 lectin-binding specificities, using enzyme-linked-immunosorbent assays with and without treatment with neuraminidase, and we analysed the relationship between these glycoforms, C4d mesangial deposits and clinical phenotypes.

RESULTS

C4d-positive vs Cd4-negative patients had higher proteinuria (median: 3.1 g/g [0.9-4.2] vs. 1.8 g/g [1-2.2]; p = 0.000), hematuria (223 cel/µL [32-278] vs 99 cel/µL [25-186], p = 0.000), and higher levels of IgA binding to neuraminidase untreated Helix Aspersa (HA IgA1 neu-) (150.6 ± 52 U vs 96.2 ± 64.1 U, p = 0.000), neuraminidase untreated Helix Pomatia (HPA IgA1 neu-) (0.34 ± 0.15 vs 0.27 ± 0.13p = 0.04), Triticum vulgaris (TV IgA1) (85.1 ± 31.7 vs42.2 ± 26.9p = 0.000), and Canavalia ensiformis (ConA IgA1) (32.5 ± 18 U vs 16.7 ± 9.38 U, p = 0.000). The levels of HA IgA1 neu-, HPA IgA1 neu-, TV IgA1 and ConA IgA1 were all associated with the mesangial deposition of C4d, extracapillary proliferation and acute kidney injury. In ROC curves, HA IgA1 neu-, HPA IgA1 neu-, TV IgA1 and ConA IgA1 significantly discriminated between C4d positive ad C4d-negative biopsies. In logistic models, TVIgA1 and ConAIgA1 were the only independent predictors of mesangial C4d deposits.

CONCLUSIONS

In IgA nephropathy, the severity of the disease is associated with the level of IgA exposing N-Acetyl-D-Galactosamine, N-Acetyl-D-Glucosamine or mannose whereas C4d deposits are only associated with elevated levels of IgA1 glycoforms exhibiting glycan residues with specificity for mannose and N-Acetyl-D-Glucosamine binding lectins.

Chemical Profiling, Antioxidant, Anticholinesterase, and Antiprotozoal Potentials of Artemisia copa Phil. (Asteraceae)

Artemisia copa Phil. (Asteraceae) (known as copa-copa) is a native species of Chile used as an infusion in traditional medicine by Atacameños people in the Altiplano, highlands of northern Chile. In this research, we have investigated for the first time the cholinesterase inhibition potential against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), and the chemical profiling of the infusions prepared from the aerial parts of A. copa by high resolution spectrometry. In addition, total phenolic, total flavonoid content, antioxidant (DPPH, FRAP, and ORAC) and antiprozoal activity were tested. Artemisia copa showed good inhibitory activity against AChE and BChE (3.92 ± 0.08 µg/ml and 44.13 ± 0.10 µg/ml). The infusion displayed a total phenolics content of 155.6 ± 2.9 mg of gallic acid equivalents/g and total flavonoid content of 5.5 ± 0.2 mg quercetin equivalents/g. Additionally, trypanocidal activity against Trypanosoma cruzi was found (LD₅₀ of 131.8 µg/ml). Forty-seven metabolites were detected in the infusion of A. copa including several phenolic acids and flavonoids which were rapidly identified using ultrahigh performance liquid chromatography orbitrap mass spectrometry analysis (UHPLC-Orbitrap-MS) for chemical profiling. The major compounds identified in the infusions were studied by molecular docking against AChE and BChE. The UHPLC-MS fingerprints generated can be also used for the authentication of these endemic species. These findings reveal that A. copa infusions can be used as beverages with protective effects.

Telemedicine and smart working: Spanish adaptation of the European Association of Urology recommendations

Introduction

Telemedicine provides remote clinical support through technology tools. It can facilitate medical care delivery while reducing unnecessary office visits. The COVID-19 outbreak has caused an abrupt change in our daily urological practice, where teleconsultations play a crucial role.

Objective

To provide practical recommendations for the effective use of technological tools in telemedicine.

Materials and methods

A literature search was conducted on Medline until April 2020. We selected the most relevant articles related to “telemedicine” and “smart working” that could provide valuable information.

Results

Telemedicine refers to the use of electronic information and telecommunication tools to provide remote clinical health care support. Smart working is a working approach that uses new or existing technologies to improve performance. Telemedicine is becoming a useful and fundamental tool during the COVID-19 pandemic and will be even more in the future. It is time for us to officially give telemedicine the place it deserves in clinical practice, and it is our responsibility to adapt and familiarize with all the tools and possible strategies for its optimal implementation. We must guarantee that the quality of care received by patients and perceived by them and their families is of the highest standard.

Conclusions

Telemedicine facilitates remote specialized urological clinical support and solves problems caused by limited patient mobility or transfer, reduces unnecessary visits to clinics and is useful to reduce the risk of COVID-19 viral transmission.

Telemedicine and smart working: Spanish adaptation of the European Association of Urology recommendations

Introducción

La telemedicina ofrece un soporte clínico remoto utilizando herramientas tecnológicas. Puede facilitar la atención médica al tiempo que reduce las visitas innecesarias a la consulta. La pandemia COVID-19 ha provocado un cambio brusco en nuestra práctica urológica diaria convirtiéndose en algo muy necesario el acto de la teleconsulta.

Objetivo

Proporcionar recomendaciones prácticas para el uso efectivo de herramientas tecnológicas en telemedicina.

Materiales y métodos

Se realizó una búsqueda en la literatura en la plataforma Medline hasta abril de 2020; seleccionamos los artículos más relevantes relacionados con «telemedicina» y «trabajo inteligente» que podrían proporcionar información útil.

Resultados

La telemedicina se refiere al uso de la información electrónica y a las herramientas de telecomunicaciones para proporcionar apoyo clínico remoto a la atención médica. El trabajo inteligente es un modelo de trabajo que utiliza tecnologías nuevas o existentes para mejorar el rendimiento. La telemedicina se está convirtiendo en una herramienta útil y necesaria durante la pandemia COVID-19 e incluso más allá de la misma. Es hora de que formalicemos y demos el lugar que se merece a la telemedicina en nuestra práctica clínica y es nuestra responsabilidad adaptar y conocer todas las herramientas y posibles estrategias para su implementación de una manera óptima, garantizar una atención de calidad a los pacientes y que dicha atención sea percibida por pacientes y familiares como de alto nivel.

Conclusiones

La telemedicina facilita la atención clínica urológica especializada a distancia y resuelve problemas como las limitaciones en la movilidad o el traslado de los pacientes, reduce las visitas innecesarias a las clínicas y es útil para reducir el riesgo de transmisión viral de la COVID-19.

SARS-CoV-2 and Aspergillus section Fumigati coinfection in an immunocompetent patient treated with corticosteroids

BACKGROUND

Patients with severe viral pneumonia are likely to receive high-dose immunomodulatory drugs to prevent clinical worsening. Aspergillus species have been described as frequent secondary pneumonia agents in severely ill influenza patients receiving steroids. COVID-19 patients admitted to Intensive Care Unit (ICU) are receiving steroids as part of their treatment and they share clinical characteristics with other patients with severe viral pneumonias. COVID-19 patients receiving steroids should be considered a putative risk group of invasive aspergillosis.

CASE REPORT

We are reporting a SARS-CoV-2/Aspergillus section Fumigati coinfection in an elderly intubated patient with a history of pulmonary embolism treated with corticosteroids. The diagnosis was made following the ad hoc definitions described for patients admitted to ICU with severe influenza, including clinical criteria (fever for 3 days refractory to the appropriate antibiotic therapy, dyspnea, pleural friction rub, worsening of respiratory status despite antibiotic therapy and need of ventilator support), a radiological criterion (pulmonary infiltrate) and a mycological criterion (several positive galactomannan tests on serum with ratio ≥0.5). In addition, Aspergillus section Fumigati DNA was found in serum and blood samples. These tests were positive 4 weeks after the patient was admitted to the ICU. The patient received voriconazole and after two month in ICU his respiratory status improved; he was discharged after 6 weeks of antifungal treatment.

CONCLUSIONS

Severely ill COVID-19 patients would be considered a new aspergillosis risk group. Galactomannan and Aspergillus DNA detection would be useful methods for Aspergillus infection diagnosis as they allow avoiding the biosafety issues related to these patients.

Renal transplantation using vascular conduit reconstruction in deceased kidneys with multiple renal arteries and short renal veins

BACKGROUND

Transplantation of kidneys with vascular anatomical variants remains a challenge. Due to its varying success in regard to graft function after transplantation, these organs have been frequently discarded assuming in advance an unaffordable rate of vascular complications.

PATIENTS AND METHODS

We performed three kidney transplants using organs from deceased donors harboring vascular variants (multiple arteries and short veins), including an unsplittable horseshoe kidney. Different grafts harvested from the same donor aorta, common iliac artery, and inferior vena cava, were used to reconstruct the initial vascular configuration by creating single arterial and venous conduits aimed to simplify the vascular anastomoses in the recipient.

RESULTS

No post-operative complications were recorded. Warm ischemia times remained comparable to single artery renal allografts. No delayed graft function was noted in any case, and every patient regained normal renal function after transplantation.

CONCLUSIONS

Vascular reconstruction using arterial and venous grafts harvested from the same deceased donor may result a helpful tool to simplify vascular anastomoses during transplantation surgery, thus avoiding their discard in advance, minimizing perioperative complications, and enabling normal graft function rates in the long-term follow-up. The successful outcome obtained by using this approach would help to expand the donor criteria for the inclusion of organs containing vascular anatomical variants.

The situation of infection in the elderly in Spain: a multidisciplinary opinion document

Infection in the elderly is a huge issue whose treatment usually has partial and specific approaches. It is, moreover, one of the areas where intervention can have the most success in improving the quality of life of older patients. In an attempt to give the widest possible focus to this issue, the Health Sciences Foundation has convened experts from different areas to produce this position paper on Infection in the Elderly, so as to compare the opinions of expert doctors and nurses, pharmacists, journalists, representatives of elderly associations and concluding with the ethical aspects raised by the issue. The format is that of discussion of a series of pre-formulated questions that were discussed by all those present. We begin by discussing the concept of the elderly, the reasons for their predisposition to infection, the most frequent infections and their causes, and the workload and economic burden they place on society. We also considered whether we had the data to estimate the proportion of these infections that could be reduced by specific programmes, including vaccination programmes. In this context, the limited presence of this issue in the media, the position of scientific societies and patient associations on the issue and the ethical aspects raised by all this were discussed.

Statistical control of processes applied to geometric uncertainties for CTV expansion margins determination in prostate cancer patients treated with VMAT: a prospective study in 57 patients

PURPOSE

To study the control graphs applicability for the geometric uncertainties of VMAT treatments in prostate cancer patients, and their use to verify the hypothesis of the data obtained randomness, to apply the margins of Van Herk expression.

MATERIAL AND METHODS

During the first 5 days of treatment, and then once a week, a Kv CBCT was performed, compared with the simulation CT and adjusted the displacements, to determine the inter-fraction errors. Immediately after radiation therapy, another CBCT was performed (for intra-fraction errors). With these data, the X, R position control charts have been made. The patients, not maintained the deviations within the charts control limits, were called "anomalies". Then, we compared the deviations and margins calculated with the van Herk expression for all patients and for those without anomalies.

RESULTS

The margins determined show appreciable differences if there were calculated for the total set of patients or for the set of them without anomalies in the control charts. For the overall set of patients, the lateral, longitudinal, and vertical margins were 0.45 cm, 0.52 cm, 0.56 cm, while for the set of patients without anomalies were 0.29 cm, 0.35 cm, and 0.38 cm.

CONCLUSIONS

The use of control charts allows tracking geometric deviations both inter and intra-fraction, variability real-time control and to detect situations in which it can change for non-random reasons, and require immediate investigation. Maintaining geometric deviations in the control state decreases the margins needed to administer a high dose to CTV in a high percentage of cancer prostate patients.

Three-piece inflatable penile prosthesis: Ectopic reservoir placement

INTRODUCTION

The complications associated to the placement of the reservoir are infrequent but potentially serious. Therefore, technical alternatives have been developed for the performance of the procedure in different locations (ectopic). The aim of this review is to revise the evidence available on the different options for the ectopic placement of the reservoir.

MATERIAL AND METHOD

Narrative review based on a bibliographical search limited to PubMed- indexed relevant manuscripts, in Spanish or English, for the period 2000-2019, using «penile prosthesis», «ectopic reservoir», radical prostatectomy», «radical cystectomy», «pelvic radiotherapy», and «renal transplantation» as key words. Non original articles and reviews were not considered eligible. A total of 11 manuscripts were included.

RESULTS

Pelvic alterations after surgery and/or radiotherapy increase the difficulty in the placement of the prosthesis reservoir. In order to minimize the risk of complications, different modifications have been performed on the devices, and technical innovations have been developed for the submuscular placement of the reservoir. The available evidence regarding the functionality and complications of these techniques is limited to single institution, low volume, and retrospective series with short follow-up periods. The functionality seems to be adequate using the adapted devices. The complications are infrequent and mild in severity.

CONCLUSIONS

Although the available evidence is still limited, the ectopic placement of the reservoir may be considered a safe, effective, and reproducible technique. In addition, it may result particularly useful in cases of altered pelvic anatomy.

Marginal Fermi Liquid in Twisted Bilayer Graphene

Linear resistivity at low temperatures is a prominent feature of high-T_{c} superconductors which has also been found recently in twisted bilayer graphene. We show that due to an extended van Hove singularity (VHS), the T-linear resistivity can be obtained from a microscopic tight-binding model for filling factors close to the VHS. The linear behavior is shown to be related to the linear energy dependence of the electron quasiparticle decay rate which implies the low-energy logarithmic attenuation of the quasiparticle weight. These are distinctive features of a marginal Fermi liquid, which we also see reflected in the respective low-temperature logarithmic corrections of the heat capacity and the thermal conductivity, leading to the consequent violation of the Wiedemann-Franz law. We also show that there is a crossover at T∼6  K from the marginal Fermi liquid regime to a regime dominated by excitations on the Dirac cone right above the VHS that also yields a linear resistivity albeit with smaller slope, in agreement with experimental observations.

Thrust stand based on a single point load cell for impulse measurements from plasma thrusters

We introduce a simple thrust stand for the direct measurement of the millinewton impulses or thrusts delivered by small thrusters intended for in-space electric propulsion. The thruster under test, with a weight below 1.5 kg, is disposed on a horizontal platform and its impulse is measured as an overweight by using a strain gauge cell physically protected from the ambient plasma and vacuum conditions. This system provides ten thrust readings per second with noise peak to peak amplitudes of 0.10-0.18 mN. The calibration procedures to verify its dynamic response to time dependent thrusts in the range of 0-15 mN using control weights as well as its minimum thrust sensitivity δT_s = 0.3 mN are discussed. Additionally, its simple conception permits a plain data reduction and analysis of steady state and low frequency thrust transients. This thrust stand was employed under low pressure and plasma ambient conditions to measure the steady impulses delivered by the Alternative Low Power Hybrid Ion Engine (ALPHIE) of 0.4-4.0 mN with absolute errors ΔT = ±0.3 mN. Finally, the experimental results show that a control electric voltage governs the ALPHIE thruster throttle.

Toward a Rational Design of Polyamine-Based Zinc-Chelating Agents for Cancer Therapies

In vitro viability assays against a representative panel of human cancer cell lines revealed that polyamines L1a and L5a displayed remarkable activity with IC₅₀ values in the micromolar range. Preliminary research indicated that both compounds promoted G1 cell cycle arrest followed by cellular senescence and apoptosis. The induction of apoptotic cell death involved loss of mitochondrial outer membrane permeability and activation of caspases 3/7. Interestingly, L1a and L5a failed to activate cellular DNA damage response. The high intracellular zinc-chelating capacity of both compounds, deduced from the metal-specific Zinquin assay and ZnL²⁺ stability constant values in solution, strongly supports their cytotoxicity. These data along with quantum mechanical studies have enabled to establish a precise structure-activity relationship. Moreover, L1a and L5a showed appropriate drug-likeness by in silico methods. Based on these promising results, L1a and L5a should be considered a new class of zinc-chelating anticancer agents that deserves further development.

The Iberian pig fed with high-fat diet: a model of renal disease in obesity and metabolic syndrome

BACKGROUND

The pathogenesis of renal disease in the context of overweight/obesity, metabolic syndrome, and insulin resistance is not completely understood. This may be due to the lack of a definitive animal model of disease, which limits our understanding of obesity-induced renal damage. We evaluated the changes in renal histology and lipid deposits induced by obesity in a model of insulin resistance: the Iberian swine fed with fat-enriched food.

METHODS

Twenty-eight female sows were randomized to standard (SD) or high-fat diet (HFD: 6.8% of saturated fat) for 100 days. Weight, adiposity, analytics, oral glucose tolerance tests, and measured renal function were determined. Renal histology and lipid deposits in renal tissue were analyzed.

RESULTS

Animals on HFD developed obesity, hypertension, high levels of LDL cholesterol, triglycerides, insulin resistance, and glomerular hyperfiltration. No animal developed overt diabetes. Animals on HFD showed "diabetoid changes", including mesangial expansion [21.40% ± 4 vs.13.20% ± 4.0, p < 0.0001], nodular glomerulosclerosis [7.40% ± 7, 0.75 vs. 2.40% ± 4.7, p = 0.02], and glomerulomegaly (18% vs. 10%, p = 0.010) than those on SD. Tubular atrophy, interstitial fibrosis, inflammation, arteriolar hyalinosis, or fibrointimal thickening were mild and similar between groups. Triglyceride content in renal tissue was higher in animals on HFD than in SD (15.4% ± 0.5 vs. 12.7% ± 0.7; p < 0.01).

CONCLUSIONS

Iberian pigs fed with fat-enriched food showed diabetoid changes and glomerulomegaly as observed in obese humans making this model suitable to study obesity-induced renal disease.

The Use of an Identifiability-Based Strategy for the Interpretation of Parameters in the 1PL-G and Rasch Models

Using the well-known strategy in which parameters are linked to the sampling distribution via an identification analysis, we offer an interpretation of the item parameters in the one-parameter logistic with guessing model (1PL-G) and the nested Rasch model. The interpretations are based on measures of informativeness that are defined in terms of odds of correctly answering the items. It is shown that the interpretation of what is called the difficulty parameter in the random-effects 1PL-G model differs from that of the item parameter in a random-effects Rasch model. It is also shown that the traditional interpretation of the guessing parameter in the 1PL-G model changes, depending on whether fixed-effects or random-effects versions of both models are considered.