The role of human virome in kidney transplant outcomes

KT is the best treatment option for eligible patients with end-stage kidney disease (ESKD). Contemporary immunosuppression for KT significantly reduced the incidence of graft rejection but, conversely, increased the risk of infection and virally mediated malignancies. As new immunosuppressive agents and antimicrobial prophylaxis are likely to be introduced, a special attention is needed for the changes in the patterns of infectious diseases and malignancy post KT. Until now, no reliable biomarker for the risk of infection has emerged to guide clinicians in adjusting the level of immunosuppression. The use of non-pathogenic viruses in combination with immune biomarkers to monitor the intensity of immunosuppression is appealing, but is yet to be proved. Increased research is required to develop and validate biomarkers that could predict rejection, infection and malignancy. This document presents a series of scientific studies that aim to enrich the current knowledge about the role of specific human viruses in different clinical outcomes both in kidney recipients and kidney donors. The 10 manuscripts included in this thesis were grouped into four main topics. The first topic refers to ethical issues concerning living kidney donation. It is of utmost importance to consider the ethical contours in which organ transplantation takes place and to make all possible efforts to assure the basic ethical principles of living kidney donation. A critical review of the most relevant ethical problems regarding financial incentives for living kidney donation was presented, providing useful additional strategies to optimize live donation. The second topic dealt with the viral biomarkers in living kidney donors (LKD). Due to organ shortage, LKD becomes an important complement to deceased donor KT, but a careful selection of LKD is crucial in order to minimize the potential risks associated with donor nephrectomy. Two manuscripts highlighted a possible role of John Cunningham virus (JCV) in the evaluation and long-term follow-up of LKD. Several factors were postulated to justify a higher prevalence of JCV viruria in LKD candidates when compared with living kidney receptors (LKR) candidates. Possible mechanisms toexplain a lower estimated glomerular filtration rate (eGFR) recovery 3 years after donation in JCV viruric donors were presented. The third topic evaluated the reactivation of potential pathogenic viruses after KT. Some viruses can establish persistent infection in immunocompetent hosts and two patterns of persistent infections are known: chronic and latent infections. Continuous prolonged viral replication and shedding are observed in chronic viral infections, as Hepatitis B (HBV), while maintenance of the viral genome without replication is found in latent viral infections, such as polyomavirus. Albeit no clear association has been detected between JCV viruria and inferior outcomes after KT, exceptional cases of JCV‐associated nephropathy have already been described. One of those cases was presented in a case report form, highlighting the role of a molecular quantitative polymerase chain reaction (qPCR) technique to confirm the presence of JCV in the allograft tissue. Previously published data showed that either JCV viremia or simultaneous urinary reactivation of JCV and BK polyomavirus (BKV) after KT are rare phenomena. To study this phenomenon, the relationships between BKV or JCV infection with graft and patient survival in a cohort of 288 KT patients followed for a median of almost 4 years were assessed. Sustained BKV viremia lead to a novel off-label approach of immunosuppression modulation. Instead of the standard approach of tacrolimus and mycophenolate reduction or suppression, we opted for combining a low dose of calcineurin inhibitor and a mammalian target of rapamycin (mTOR) inhibitor. Episodes of acute rejection, patient and graft survival and eGFR were evaluated at the end of follow-up in one of the largest studies evaluating the outcomes of KT recipients expressing JCV or BKV viruria and viremia for a prolonged period. KT recipients are at an increased risk for urothelial carcinoma. Nevertheless, human polyomaviruses have recently been categorized as “possible carcinogens”, and a role for JCV in human cancers is not yet proved. A case report establishing the oncogenicity of JCV in the development of bladder cancer through specific immunochemical staining and specific in‐house real‐time qPCR was presented, highlighting the potential long‐ term risk for urothelial malignancies in KT patients with JCV nephropathy. In patients with resolved HBV infection, i.e., those with positive antibody to hepatitis B core antigen (anti-HBc) but negative plasmatic hepatitis B surface antigen (HBsAg), viral reactivation can occur at any time after the introduction of immunosuppressive therapies and can lead to life‐threatening complications. To clarify the incidence of HBV reactivation after KT, a cohort of 70 patients with previous resolved HBV infection was studied. Outcome data regarding patient and graft survival comparing anti‐HBc‐ positive patients and global population of transplant unit were presented. In addition, the prescription of prophylactic antiviral therapy for HBsAg‐negative/anti‐HBc‐positive patients after KT was critically reviewed. The fourth and last topic refers to a recent concept of viruses as biomarkers of immunosuppression status after KT. The main focus is on Torque teno virus (TTV). This virus has not been associated with any specific disease, but recent studies evaluated whether peripheral blood levels of TTV might reflect the overall strength of innate and specific immunity. An inverse correlation between immune competence and TTV replication might be a promising strategy to contribute to evaluate immune function in KT patients. Initially, a case report was presented, unveiling the kinetics of TTV DNA load during a mild course of Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infection with prolonged viral shedding and failed antibody response, in a patient infected 3 months after receiving a KT. Thereafter, an original study performed to evaluate if TTV load before vaccination was associated with anti-spike (anti-S) total antibody formation in response to two doses of SARS-CoV-2 mRNA BNT162b2 vaccine in KT patients was described. Seroconversion rates after vaccination under different immunosuppressive medications were presented, as well as, the potential of TTV loads at baseline to predict the development of anti-S antibodies after two doses of vaccine. A cut-off of TTV viral load was calculated and proved to be able to predict the failure to develop antibodies. The third study on this topic focused on a prospective observational cohort study designed to evaluate TTV viral load in KT patients during the first year post-transplant, examining the overall kinetics and their relationships with deleterious events, including episodes of infection and the formation of de novo donor-specific antibodies (DSAs). The detection of an infectious event in the first year after KT was more probable among patients with higher increases in TTV viral load between the 1 st week and the 1st month after KT. Additionally, a cut-off value of TTV viral load variation between these time points which best discriminated patients with and without infection was established. Finally, a reflection was made about the major results of this compilation of studies and the future perspectives that lie ahead

Experiential learning as a construct for child motivation

Experiential learning results from involvement, participation, exploration, experimentation, creation, discovery, relationships, and interaction with others and objects, in short, interaction with the world around us. In other words, everyone learns motivated by their purposes, i.e. they deliberately strive to achieve learning that makes sense to them. Motivation and learning are fundamental to the study of new school theories. It cannot, and should not, be seen only as an essential characteristic for the child, but must be mediated by the teacher, supported by various strategies to promote motivation for learning. The study presented here focused on experiential learning as a pedagogy and the teaching-learning strategies that correspond to it. The work was carried out with 24 children, aged 9 and 10, in the 4th year of primary school. The study is based on a qualitative, interpretive approach. Data was collected mainly through the technique of direct and participant observation, using field notes, photographic records, and observation grids. The objectives were: to identify the advantages and disadvantages of experiential work, to understand whether experiential work is a motivating factor, and to study the role of the child in the development of experiential work. The results obtained in the study, which emerged from the application of various data collection instruments, revealed that the children were more active, autonomous, and participative, verifying that experiential learning, using diversified strategies, boosts children's involvement, and stimulates their curiosity and their love of learning. We were also able to see that experiential learning has a greater impact on children's motivation if the teacher presents him/herself to them as an example of a motivated person.info:eu-repo/semantics/publishedVersio

Prática de Ensino Supervisionada em Educação Pré-Escolar e Ensino do 1.º Ciclo do Ensino Básico

O estudo que aqui se apresenta teve como foco investigacional a aprendizagem experiencial enquanto pedagogia e as estratégias de ensino-aprendizagem que lhe correspondem. O trabalho foi desenvolvido no âmbito da Unidade Curricular da Prática de Ensino Supervisionada (PES), integrada no Mestrado em Educação Pré-Escolar (EPE) e Ensino do 1.º Ciclo do Ensino Básico (1.º CEB), e a ação educativa desenvolveu-se com 3 grupos diferentes, nomeadamente, no âmbito de Creche, Jardim de Infância e 1.ºCEB. Trata-se de um estudo em múltiplos contextos, revelando-se cada contexto de intervenção como um caso específico de análise. O estudo assenta numa abordagem qualitativa, de cariz interpretativo. Ao longo de toda a prática assumiu-se uma atitude reflexiva e crítica em relação ao trabalho desenvolvido. A recolha de dados, foi feita principalmente, através da observação direta, com recurso às notas de campo, ao registo fotográfico, e a entrevistas aos educadores e professores cooperantes. Em contexto de 1.ºCEB utilizaram-se ainda grelhas de observação. Partiu-se da questão: Que estratégias de ensino e aprendizagem podem ser promotoras de um trabalho experiencial que possibilitem a mobilização de saberes em situações problemáticas quotidianas em contextos de creche, jardim de infância e 1.º ciclo do ensino básico? E estabeleceram-se como objetivos: (i) perceber a importância do trabalho experiencial no processo de ensino-aprendizagem; (ii) identificar as vantagens e desvantagens do trabalho experiencial procurando entender se o trabalho experiencial é um fator de motivação e interesse para a criança; (iii) conhecer as ideias e opiniões que os professores e educadores têm acerca do trabalho experiencial; (iv) conceber, desenvolver e analisar experiências de ensino-aprendizagem que permitam à criança assumir-se como construtor do próprio conhecimento; (v) analisar o papel da criança no desenvolvimento do trabalho experiencial; (vi) recorrer a estratégias diversificadas e potenciadoras de um trabalho experiencial. Os resultados obtidos no estudo, que emergiram da aplicação de vários instrumentos de recolha de dados, durante o desenvolvimento das experiências de ensino-aprendizagem (EEA) baseadas no trabalho experiencial, revelaram que as crianças foram ativas, autónomas e participativas durante a sua realização, verificando-se assim, que o trabalho experiencial com recurso a estratégias de ensino-aprendizagem diversificadas, potencia o envolvimento das crianças, estimula a sua curiosidade e o gosto pela aprendizagem.The presented study is focused on experiential learning as a pedagogy and the teaching and learning strategies that correspond to it. The work was developed within the scope of the Curricular Unit of the Supervised Teaching Practice (STP), integrated in Master of Pre-School Education (MPE) and Elementary School - Basic Education. The educational action was developed with 3 different groups: day care, kindergarden and elementary school. This study has multiple contexts, revealing each context of intervention as a specific case of analysis, and it's based on a qualitative, interpretive approach. Throughout this, a reflexive and critical attitude towards the work developed was assumed. Data collection was mainly done through direct observation, using field notes, photographic records, and interviews with educators and cooperating teachers. For the 1st grade, were also used observation grids. The following question emerged: Which teaching and learning strategies can be the promoters of an experiential work that enables the mobilization of knowledge in everyday problematic situations in day-care, kindergarten and elementary school contexts? And they were established as objectives: (i) to realize the importance of experiential work as teaching and learning process; (ii) identify the advantages and disadvantages of experiential work, understanding if experiential work is a motivating factor and interest for the child; (iii) to know the ideas and opinions that teachers and educators have about experiential work; (iv) designing, developing and analyzing teaching-learning experiences that allow the child to become a constructor of its own knowledge; (v) analyze the child's role in the development of experiential work; (vi) to follow diversified and empowering strategies for experiential work. The results on this research, which emerged from the data collection instruments, during the development of teaching-learning experiences based on experiential work, revealed that the children were active, autonomous and participative during that experiential work using a variety of teaching and learning strategies strengthens the involvement of children, stimulates their curiosity and the taste for learning

The state of the art

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“Keeping the Light On”: A Qualitative Study on Hope Perceptions at the End of Life in Portuguese Family Dyads

Funding: This work is funded by national funds through FCT—Fundação para a Ciência e a Tecnologia, I.P. (UIDB/05704/2020 and UIDP/05704/2020), CCISP-HES.SO Collaborative Research, and under the Scientific Employment Stimulus-Institutional Call—[CEECINST/00051/2018].Abstract: Hope performs an important role in how patients and their families cope with suffering and stressful events. To better inform practice and theory on hope, palliative care research should include both patients and their family carers, given their strong interdependence. The aim of this study was to explore how hope is experienced in dyads formed by end-of-life patients and their family carers. In this qualitative study, data were collected by in-depth interviews with seven Portuguese family dyads. Analysis followed a thematic analysis approach. The analysis of the interviews shed light on the importance of hope for all participants, and the challenges involved. Family dyads noted several barriers and facilitators to perceptions of hope. Barriers to hope included limitations imposed by illness, feelings of anguish and helplessness, and poor communication with clinicians. Hope facilitators included supportive others, positive thinking and sense of humour, connection with nature, faith in religion and science, and a sense of compassion with others and altruism. Given the multidimensional scope of hope, the main challenge for family dyads is to look beyond the disease itself. Thus, palliative care teams should be encouraged to support and foster realistic hope, helping families prepare for death, in the context of advanced cancer.info:eu-repo/semantics/publishedVersio

A Prospective Cohort Study

Funding Information: The present publication was funded by Fundação Ciência e Tecnologia, IP national support through CHRC (UIDP/04923/2020). Publisher Copyright: © 2023 by the authors.Torque teno virus (TTV) was recently identified as a potential biomarker for the degree of immunosuppression, and potentially as a predictor of rejection and infection in solid organ transplant patients. We evaluated TTV viral load in kidney transplant (KT) patients during the first year post-transplant to examine overall kinetics and their relationships with deleterious events, including episodes of infection and the formation of de novo donor-specific antibodies (DSAs). In a single-center, prospective observational cohort study, 81 KT patients were monitored at baseline, week 1, and month 1, 3, 6, 9 and 12, post-KT, and whenever required by clinical events. Kidney function, plasma TTV load, immunoglobulins and lymphocyte subpopulations were assessed at each time point. Twenty-six patients (32.1%) presented a total of 38 infection episodes post-KT. Induction immunosuppression with thymoglobulin, compared to basiliximab, was not associated with more infections (p = 0.8093). Patients with infectious events had lower T-cells (p = 0.0500), CD8+ T-cells (p = 0.0313) and B-cells (p = 0.0009) 1 month post-KT, compared to infection-free patients. Patients with infection also showed higher increases in TTV viral loads between week 1- month 1, post-KT, with TTV viral load variations >2.65 log10 cp/mL predicting the development of infectious events during the 12-month study period (p < 0.0001; sensitivity 99.73%; specificity 83.67%). Patients who developed de novo DSAs had lower TTV DNA viral loads at month 12 after KT, compared to patients who did not develop DSA (3.7 vs. 5.3 log10 cp/mL, p = 0.0023). Briefly, evaluating early TTV viremia is a promising strategy for defining infectious risk in the 1st year post-KT. The availability of standardized commercial real-time PCR assays is crucial to further validate this as an effective tool guiding immunosuppression prescription.publishersversionpublishe

Torquetenovirus viral load is associated with anti-spike antibody response in SARS-CoV-2 mRNA BNT162b2 vaccinated kidney transplant patients

Introduction: Kidney transplant patients (KT) are at high risk for severe COVID-19 and presented attenuated antibody responses to vaccination when compared to immunocompetent individuals. Torquetenovirus (TTV) has recently gained attention as a potential surrogate marker of the net state of immunosuppression. We evaluated the association between pre-vaccination TTV viral load and anti-spike total antibody response to SARS-CoV-2 vaccination in KT. Material and Methods: The 114 adult KT recipients enrolled in this prospective single-center cohort study received two doses of SARS-CoV-2 mRNA BNT162b2 vaccine. Serum samples were collected immediately before vaccination at the days when patients received both the first (T0) and the second dose (T1) and 16–45 days after the second dose (T2). Primary endpoint was the development of anti-spike total antibodies after vaccination. Demographic, clinical, and laboratorial parameters were compared between patients with and without detectable SARS-CoV-2 antibodies at T2. Results: Ninety-nine patients (86.8%) were naïve for SARS-CoV-2 before vaccination. Fifty-six (56.6%) patients developed anti-spike total antibodies at T2. The use of mTOR inhibitors was associated with a favorable response (p =.005); conversely, mycophenolic acid (MPA) was associated with a negative response (p =.006). In a multivariable model, the presence of TTV at T0 ≥ 3.36 log10 cp/ml was associated with unfavorable vaccine response (OR: 5.40; 95% CI: 1.47–19.80; p =.011), after adjusting for age and eGFR at T0. Conclusions: Higher TTV viral loads before vaccination are associated with reduced anti-spike total antibody response in SARS-CoV-2 mRNA BNT162b2 vaccinated KT patients. The association between TTV viral load and vaccine response may be an added-value in the optimization of vaccination regimens in KT.publishersversionpublishe

Polygenicity and Epistasis Underlie Fitness-Proximal Traits in the Caenorhabditis elegans Multiparental Experimental Evolution (CeMEE) Panel

The deposited article is a pre-print version and it has not been submitted to peer reviewing. This article version was provided by bioRxiv and is the preprint first posted online Mar. 26, 2017. This publication hasn't any creative commons license associated. The deposited article version contains attached the supplementary materials within the pdf.Understanding the genetic basis of complex traits remains a major challenge in biology. Polygenicity, phenotypic plasticity and epistasis contribute to phenotypic variance in ways that are rarely clear. This uncertainty can be problematic for estimating heritability, for predicting individual phenotypes from genomic data, and for parameterizing models of phenotypic evolution. Here we report an advanced recombinant inbred line (RIL) quantitative trait locus (QTL) mapping panel for the hermaphroditic nematode Caenorhabditis elegans, the C. elegans multiparental experimental evolution (CeMEE) panel. The CeMEE panel, comprising 507 RILs at present, was created by hybridization of 16 wild isolates, experimental evolution for 140-190 generations, and inbreeding by selfing for 13-16 generations. The panel contains 22% of single nucleotide polymorphisms known to segregate in natural populations, and complements existing C. elegans mapping resources by providing fine resolution and high nucleotide diversity across >95% of the genome. We apply it to study the genetic basis of two fitness components, fertility and hermaphrodite body size at time of reproduction, with high broad sense heritability in the CeMEE. While simulations show we should detect common alleles with additive effects as small as 5%, at gene-level resolution, the genetic architectures of these traits does not feature such alleles. We instead find that a significant fraction of trait variance, approaching 40% for fertility, can be explained by sign epistasis with main effects below the detection limit. In congruence, phenotype prediction from genomic similarity, while generally poor (r2 < 10%), requires modeling epistasis for optimal accuracy, with most variance attributed to the rapidly evolving chromosome arms.National Science Foundation grant: (PHY-1125915); National Institutes of Health grants: (R25-GM-067110, R01-GM-089972, R01-GM-121828); Gordon and Betty Moore Foundation grant: (2919.01); Human Frontiers Science Program (RGP0045/2010); European Research Council grant: (FP7/2007-2013/243285); Agence Nationale de la Recherche grant: (ANR-14-ACHN-0032-01).info:eu-repo/semantics/publishedVersio

Gastrointestinal Bleeding and Diffuse Skin Thickening as Kaposi Sarcoma Clinical Presentation

A 56-year-old African patient received a kidney from a deceased donor with 4 HLA mismatches in April 2013. He received immunosuppression with basiliximab, tacrolimus, mycophenolate mofetil, and prednisone. Immediate diuresis and a good allograft function were soon observed. Six months later, the serum creatinine level increased to 2.6 mg/dL. A renal allograft biopsy revealed interstitial fibrosis and tubular atrophy grade II. Toxicity of calcineurin inhibitor was assumed and, after a switch for everolimus, renal function improved. However, since March 2014, renal function progressively deteriorated. A second allograft biopsy showed no new lesions. Two months later, the patient was admitted due to anuria, haematochezia with anaemia, requiring 5 units of packed red blood cells, and diffuse skin thickening. Colonoscopy showed haemorrhagic patches in the colon and the rectum; histology diagnosis was Kaposi sarcoma (KS). A skin biopsy revealed cutaneous involvement of KS. Rapid clinical deterioration culminated in death in June 2014. This case is unusual as less than 20 cases of KS with gross gastrointestinal bleeding have been reported and only 6 cases had the referred bleeding originating in the lower gastrointestinal tract. So, KS should be considered in differential diagnosis of gastrointestinal bleeding in some kidney transplant patients