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1.
J Med Genet ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38977299

RESUMEN

OBJECTIVE: This study aims to develop and internally validate a clinical risk score to predict incident renal angiomyolipoma (AML) and pulmonary lymphangioleiomyomatosis (LAM) in people with tuberous sclerosis complex (TSC). STUDY DESIGN: Data from 2420 participants in the TSC Alliance Natural History Database were leveraged for these analyses. Logistic regression was used to predict AML and LAM development using 10 early-onset clinical manifestations of TSC as potential predictors, in addition to sex and genetic mutation. For our models, we divided AML into three separate outcomes: presence or absence of AML, unilateral or bilateral and whether any are ≥3 cm in diameter. The resulting regression models were turned into clinical risk scores which were then internally validated using bootstrap resampling, measuring discrimination and calibration. RESULTS: The lowest clinical risk scores predicted a risk of AML and LAM of 1% and 0%, while the highest scores predicted a risk of 99% and 73%, respectively. Calibration was excellent for all three AML outcomes and good for LAM. Discrimination ranged from good to strong. C-statistics of 0.84, 0.83, 0.83 and 0.92 were seen for AML, bilateral AML, AML with a lesion≥3 cm and LAM, respectively. CONCLUSION: Our work is an important step towards identifying individuals who could benefit from preventative strategies as well as more versus less frequent screening imaging. We expect that our work will allow for more personalised medicine in people with TSC. External validation of the risk scores will be important to confirm the robustness of our findings.

2.
Gene ; 927: 148731, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38944164

RESUMEN

Vascular calcification is prevalent in chronic kidney disease (CKD). Genetic causes of CKD account for 10-20% of adult-onset disease. Vascular calcification is thought to be one of the most important risk factors for increased cardiovascular morbidity and mortality in CKD patients and is detectable in 80% of patients with end stage kidney disease (ESKD). Despite the high prevalence of vascular calcification in CKD, no single gene cause has been described. We hypothesized that variants in vascular calcification genes may contribute to disease pathogenesis in CKD, particularly in families who exhibit a predominant vascular calcification phenotype. We developed a list of eight genes that are hypothesized to play a role in vascular calcification due to their involvement in the ectopic calcification pathway: ABCC6, ALPL, ANK1, ENPP1, NT5E, SLC29A1, SLC20A2, and S100A12. With this, we assessed exome data from 77 CKD patients, who remained unsolved following evaluation for all known monogenic causes of CKD. We also analyzed an independent cohort (Ontario Neurodegenerative Disease Research Initiative (ONDRI), n = 520) who were screened for variants in ABCC6 and compared this to a control cohort of healthy adults (n = 52). We identified two CKD families with heterozygous pathogenic variants (R1141X and A667fs) in ABCC6. We identified 10 participants from the ONDRI cohort with heterozygous pathogenic or likely pathogenic variant in ABCC6. Replication in a healthy control cohort did not reveal any variants. Our study provides preliminary data supporting the hypothesis that ABCC6 may play a role in vascular calcification in CKD. By screening CKD patients for genetic causes early in the diagnostic pathway, patients with genetic causes associated with vascular calcification can potentially be preventatively treated with new therapeutics with aims to decrease mortality.

3.
Transplant Proc ; 56(1): 50-57, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38199855

RESUMEN

Expanded criteria donor (ECD) kidneys experience suboptimal outcomes compared with standard criteria donor kidneys. To examine the additional impact of deceased organ category, donation after circulatory death (DCD), and neurologic determination of death (NDD) on ECD outcomes, we examined 1- and 3-year patient and graft survival in all ECD kidney recipients in our institution between January 2008 and December 2017. Of 166 ECD recipients, 49 (29.5%) were DCD and 117 (70.5%) were NDD. Delayed graft function was higher in the DCD/ECD group 61.2 % vs 32.0 % among NDD/ECD recipients. Graft loss was significantly increased among DCD/ECD (hazard ratio for graft loss 4.81 [95% CI1.78-13.01], P = .002 at 1 year and 2.03 [95% CI 1.03-4.0], P = .042 at 3 years). Death-censored graft loss was higher among DCD/ECD (hazard ratio was 10.12 [95% CI, 2.14, 47.92], P = .004 at 1 year and 2.83 [95% CI, 1.24, 6.46], P = .014 at 3 years). There was no statistically significant difference in all-cause mortality. Our study demonstrated that DCD/ECD kidneys have lower graft survival compared with NDD/ECD kidneys. Time on dialysis, waiting time, and panel reactive antibody should be taken into account when offering these organs to patients.


Asunto(s)
Trasplante de Riñón , Obtención de Tejidos y Órganos , Humanos , Trasplante de Riñón/efectos adversos , Diálisis Renal , Donantes de Tejidos , Supervivencia de Injerto , Estudios Retrospectivos
4.
Can J Kidney Health Dis ; 10: 20543581231205334, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37920776

RESUMEN

Background: We previously published a retrospective study of kidney biopsies performed in a tertiary care hospital in London, Ontario from 2012 to 2017. This study resulted in a change of practice in our institution to shorter postbiopsy monitoring for outpatients as well as the development of a risk calculator to predict serious bleeding complications. Objective: The primary objective of this study was to determine whether this shorter monitoring time is adequate in the outpatient setting. A secondary objective was to validate the bleeding risk calculator in both inpatients and outpatients. Design: This was a retrospective chart review. Setting: This study was performed at a tertiary academic hospital in London, Ontario, Canada. Participants: This was a retrospective study of 400 adult patients who underwent kidney biopsy between April 30, 2018 and February 25, 2022 at a tertiary academic hospital in London, Canada. Methods: We retrospectively assessed frequency and timing of major bleeding complications in patients who underwent kidney biopsy. In secondary analyses, we examined the prediction performance of the risk calculator in discrimination and calibration. Results: Major bleeding occurred in 7 patients (1.8%). Five of these patients required blood transfusions (1.3%) and 2 required embolization (0.5%). In the outpatient setting, any major bleeding events were identified immediately (1 patient) or on the routine 2-hour ultrasounds (1 patient). The risk calculator showed good discrimination (C-statistic, 0.91, 95% confidence interval [CI] = [0.84 to 0.95]) and calibration (slope, 1.10, 95% CI = [0.47 to 1.74]; intercept, 95% CI = -0.02 [-0.79 to 0.75]), but with much uncertainty in the estimates. Limitations: The occurrence of only a few major bleeding events limits the reliability of our assessment of our risk calculator. Conclusions: There appears to be little yield in extending observation beyond 2 hours after an outpatient kidney biopsy with the use of immediate and 2-hour postbiopsy ultrasounds. The bleeding risk calculator (http://perioperativerisk.com/kbrc) warrants further validation.


Contexte: Nous avons publié précédemment une étude rétrospective des biopsies rénales effectuées entre 2012 et 2017 dans un hôpital de soins tertiaires de London, en Ontario. Les résultats de cette précédente étude ont entraîné un changement de pratique dans notre établissement, soit une réduction de la durée de la surveillance post-biopsie pour les patients ambulatoires, et la mise au point d'un calculateur de risque permettant de prédire les complications hémorragiques graves. Objectifs: L'objectif principal de l'étude en cours était de vérifier si ce temps de surveillance plus court est adéquat pour les patients ambulatoires. Un deuxième objectif était de valider le calculateur de risque d'hémorragie chez les patients hospitalisés et les patients ambulatoires. Conception: Étude rétrospective des dossiers médicaux. Cadre: Étude réalisée dans un hôpital de soins tertiaires de London, en Ontario (Canada). Sujets: Cette étude rétrospective portait sur 400 patients adultes ayant subi une biopsie rénale entre le 30 avril 2018 et le 25 février 2022 dans un centre hospitalier universitaire de soins tertiaires de London, au Canada. Méthodes: Nous avons procédé à un examen rétrospectif de la fréquence des complications hémorragiques graves, et du moment où celles-ci surviennent, chez les patients ayant subi une biopsie rénale. Dans les analyses secondaires, nous avons examiné la puissance prédictive du calculateur de risque en matière de discrimination et d'étalonnage. Résultats: Sept patients (1,75 %) ont subi une hémorragie majeure; de ces patients, cinq ont eu besoin de transfusions sanguines (1,3 %) et deux, d'une embolisation (0,5 %). En contexte ambulatoire, tous les événements hémorragiques graves ont été détectés immédiatement (un patient) ou lors de l'échographie de routine à deux heures (un patient). Le calculateur de risque a montré une bonne discrimination (statistique C : 0,91 [IC 95 % : 0,84 à 0,95]) et un bon étalonnage (pente : 1,10 [0,47 à 1,74]; point d'intersection : -0,02 [-0,79 à 0,75]), mais une grande incertitude dans les estimations. Limitations: La fiabilité de l'évaluation de notre calculateur de risque est limitée par le très faible échantillon d'événements hémorragiques graves étant survenus. Conclusion: Il semble y avoir peu d'intérêt à prolonger la surveillance au-delà de deux heures après une biopsie rénale chez les patients ambulatoires lorsqu'une échographie est pratiquée immédiatement après la procédure et deux heures plus tard. Le calculateur de risque d'hémorragie (http://perioperativerisk.com/kbrc) nécessite une validation plus approfondie.

5.
Am J Kidney Dis ; 82(6): 772-775, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37532078

RESUMEN

Declining kidney function in tuberous sclerosis complex (TSC) is often attributed to large lesions, including angiomyolipomas (AMLs) and cysts, that encroach on the normal parenchyma or that require intervention and loss of parenchyma from surgical debulking or embolization. Consequently, research on inhibitors of the mammalian target of rapamycin (mTOR), a protein complex implicated in TSC pathophysiology for its role in promoting cell growth and proliferation, has largely focused on their ability to reduce AML size. Clinical guidelines distilled from this research limit mTOR inhibition as a first-line treatment to patients with large AMLs. However, chronic kidney disease (CKD) occurs in patients without large AMLs or a history of renal intervention. Alternate mechanisms postulated for CKD in TSC may suggest a role for mTOR inhibition in this population. In this report, we present 2 cases of a microscopic variant of TSC kidney disease causing declining kidney function, as well as anecdotal evidence for the use of mTOR inhibition to improve kidney function in the absence of large AMLs. We highlight the importance of annual kidney function assessment in patients with TSC and suggest a low threshold for kidney biopsy in patients with declining glomerular filtration rate without a clear etiology clinically or radiographically.


Asunto(s)
Angiomiolipoma , Neoplasias Renales , Insuficiencia Renal Crónica , Esclerosis Tuberosa , Humanos , Esclerosis Tuberosa/complicaciones , Esclerosis Tuberosa/tratamiento farmacológico , Esclerosis Tuberosa/patología , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/complicaciones , Sirolimus/uso terapéutico , Riñón/patología , Angiomiolipoma/tratamiento farmacológico , Angiomiolipoma/etiología , Angiomiolipoma/patología , Serina-Treonina Quinasas TOR , Insuficiencia Renal Crónica/complicaciones
6.
Am J Med ; 136(12): 1147-1159, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37380060

RESUMEN

Chronic kidney disease patients are at increased risk of cardiovascular disease, which is the leading cause of mortality among this population. In addition, chronic kidney disease is a major risk factor for the development of coronary artery disease and is widely regarded as a coronary artery disease risk equivalent. Medical therapy is the cornerstone of coronary artery disease management in the general population. However, there are few trials to guide medical therapy of coronary artery disease in chronic kidney disease, with most data extrapolated from clinical trials of mainly non-chronic kidney disease patients, which were not adequately powered to evaluate this subgroup. There is some evidence to suggest that the efficacy of certain therapies such as aspirin and statins is attenuated with declining estimated glomerular filtration rate, with questionable benefit among end-stage renal disease (ESRD) patients. Furthermore, chronic kidney disease and ESRD patients are at higher risk of potential side effects with therapy, which may limit their use. In this review, we summarize the available evidence supporting the safety and efficacy of medical therapy of coronary artery disease in chronic kidney disease and ESRD patients. We also discuss the data on new emerging therapies, including PCSK9i, SGLT2i, GLP1 receptor agonists, and nonsteroidal mineralocorticoid receptor antagonists, which show promise at reducing risk of cardiovascular events in the chronic kidney disease population and may offer additional treatment options. Overall, dedicated studies directly evaluating chronic kidney disease patients, particularly those with advanced chronic kidney disease and ESRD, are greatly needed to establish the optimal medical therapy for coronary artery disease and improve outcomes in this vulnerable population.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad de la Arteria Coronaria , Fallo Renal Crónico , Insuficiencia Renal Crónica , Humanos , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/epidemiología , Insuficiencia Renal Crónica/epidemiología , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Enfermedades Cardiovasculares/prevención & control , Enfermedades Cardiovasculares/complicaciones , Factores de Riesgo
7.
Kidney Med ; 5(6): 100641, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37274539

RESUMEN

Rationale & Objective: Continuous kidney replacement therapy (CKRT) is the predominant form of acute kidney replacement therapy used for critically ill adult patients with acute kidney injury (AKI). Given the variability in CKRT practice, a contemporary understanding of its epidemiology is necessary to improve care delivery. Study Design: Multicenter, prospective living registry. Setting & Population: 1,106 critically ill adults with AKI requiring CKRT from December 2013 to January 2021 across 5 academic centers and 6 intensive care units. Patients with pre-existing kidney failure and those with coronavirus 2 infection were excluded. Exposure: CKRT for more than 24 hours. Outcomes: Hospital mortality, kidney recovery, and health care resource utilization. Analytical Approach: Data were collected according to preselected timepoints at intensive care unit admission and CKRT initiation and analyzed descriptively. Results: Patients' characteristics, contributors to AKI, and CKRT indications differed among centers. Mean (standard deviation) age was 59.3 (13.9) years, 39.7% of patients were women, and median [IQR] APACHE-II (acute physiologic assessment and chronic health evaluation) score was 30 [25-34]. Overall, 41.1% of patients survived to hospital discharge. Patients that died were older (mean age 61 vs. 56.8, P < 0.001), had greater comorbidity (median Charlson score 3 [1-4] vs. 2 [1-3], P < 0.001), and higher acuity of illness (median APACHE-II score 30 [25-35] vs. 29 [24-33], P = 0.003). The most common condition predisposing to AKI was sepsis (42.6%), and the most common CKRT indications were oliguria/anuria (56.2%) and fluid overload (53.9%). Standardized mortality ratios were similar among centers. Limitations: The generalizability of these results to CKRT practices in nonacademic centers or low-and middle-income countries is limited. Conclusions: In this registry, sepsis was the major contributor to AKI and fluid management was collectively the most common CKRT indication. Significant heterogeneity in patient- and CKRT-specific characteristics was found in current practice. These data highlight the need for establishing benchmarks of CKRT delivery, performance, and patient outcomes. Data from this registry could assist with the design of such studies.

8.
ACS Omega ; 8(17): 15160-15167, 2023 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-37151562

RESUMEN

Glomerular filtration rate (GFR) is the most widely used tool for the measurement of kidney function, but endogenous biomarkers such as cystatin C and creatinine have limitations. A previous metabolomic study revealed N,N,N-trimethyl-L-alanyl-L-proline betaine (TMAP) to be reflective of kidney function. In this study, we developed a quantitative LCMS assay for the measurement of TMAP and evaluated TMAP as a biomarker of GFR. An assay to measure TMAP was developed using liquid chromatography-mass spectrometry. After validation of the method, we applied it to plasma samples from three distinct kidney disease patient cohorts: nondialysis chronic kidney disease (CKD) patients, patients receiving peritoneal and hemodialysis, and living kidney donors. We investigated whether TMAP was conserved in other mammalian and nonmammalian species, by analyzing plasma samples from Wistar rats with diet-induced CKD and searching for putative matches to the m/z for TMAP and its known fragments in the raw sample data repository "Metabolomics Workbench". The assay can measure plasma TMAP at a lower limit of quantitation (100 ng/mL) with an interday precision and accuracy of 12.8 and 12.1%, respectively. In all three patient cohorts, TMAP concentrations are significantly higher in patients with CKD than in controls with a normal GFR. Further, TMAP concentrations are also elevated in rats with CKD and TMAP is present in the sap produced from Acer saccharum trees. TMAP concentration is inversely related to GFR suggesting that it is a marker of kidney function. TMAP is present in nonmammalian species suggesting that it is part of a biologically conserved process.

9.
Proc Biol Sci ; 290(1999): 20230432, 2023 05 31.
Artículo en Inglés | MEDLINE | ID: mdl-37253427

RESUMEN

Organisms use resource allocation strategies to survive seasonal environmental changes and life-history stage transitions. Earlier studies found a transcription cofactor, vgll3, associating with maturation timing that inhibits adipogenesis in mice and affects body condition in juvenile salmon. Owing to a lack of temporal studies examining seasonality effects on phenotypes such as vgll3 genotype, body condition, maturation and different life stages, we investigated the influence of different larval and juvenile temperatures, vgll3 genotype and interactions with body condition and maturation rate. We reared Atlantic salmon for 2 years in four larval-juvenile phase temperature groups until the occurrence of mature males. We found no effect of larval temperature on the measured phenotypes or maturation rate. However, we observed an increased maturation rate in individuals of the warm juvenile temperature treatment and differences in body condition associated with vgll3 genotype. Early maturation genotype individuals had a less variable body condition across seasons compared with late maturation genotype individuals. This result suggests a vgll3 influence on resource allocation strategies; possibly linked with the early maturation process, with early maturation genotype individuals having a higher maturation rate and a higher body condition in the spring.


Asunto(s)
Salmo salar , Maduración Sexual , Masculino , Animales , Ratones , Estaciones del Año , Maduración Sexual/genética , Genotipo , Fenotipo , Estadios del Ciclo de Vida , Salmo salar/genética
10.
Transpl Infect Dis ; 25(4): e14081, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37247212

RESUMEN

BACKGROUND: Delayed graft function (DGF) increases the renal allograft failure risk. Late-onset Cytomegalovirus (CMV) infection's effect on the association between DGF and allograft failure has not been determined. METHODS: In this retrospective cohort, we included all renal allograft recipients at London Health Sciences Centre from January 1, 2014 to December 30, 2017, and continued clinical follow-up until February 28, 2020. We determined whether late-onset CMV infection affects the association between DGF and allograft failure in stratified and Cox proportional hazard analyses. RESULTS: Of 384 patients (median age [interquartile range]: 55 [43.3-63]; 38.7% female), 57 recipients (14.8%) were diagnosed with DGF. Patients with DGF were at a greater risk of CMV infection than patients without DGF (22.8% vs. 11.3%, p = .017). Late-onset CMV infection (odds ratio [OR]: 4.7, 95% CI: 2.07-10.68) and rejection (OR: 9.59, 95% CI: 4.15-22.16) significantly increased the risk of allograft failure in recipients with DGF. Patients with DGF had a significantly greater risk of graft failure than those without DGF (17.5% vs. 6.1%, p = .007). In the adjusted Cox hazard model, CMV infection significantly increased the risk of allograft failure (aHR: 3.19, 95% CI: 1.49-6.84). CONCLUSION: Late-onset CMV infection considerably increased the risk of graft failure in patients with DGF. A hybrid preventive model including prophylaxis followed by CMV-specific cell-mediated immunity monitoring may decrease the risk of allograft failure in recipients with DGF.


Asunto(s)
Infecciones por Citomegalovirus , Trasplante de Riñón , Insuficiencia Renal , Humanos , Femenino , Masculino , Trasplante de Riñón/efectos adversos , Estudios Retrospectivos , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/epidemiología , Riñón , Citomegalovirus , Progresión de la Enfermedad , Aloinjertos
12.
Conserv Physiol ; 11(1): coac086, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36726866

RESUMEN

Age at maturity is a key life history trait involving a trade-off between survival risk and reproductive investment, and is an important factor for population structures. In ectotherms, a warming environment may have a dramatic influence on development and life history, but this influence may differ between populations. While an increasing number of studies have examined population-dependent reactions with temperature, few have investigated this in the context of maturation timing. Atlantic salmon, a species of high conservation relevance, is a good study species for this topic as it displays considerable variation in age at maturity, of which a large proportion has been associated with a genomic region including the strong candidate gene vgll3. Until now, the effect of this gene in the context of different environments and populations has not been studied. Using a large-scale common-garden experiment, we find strong effects of temperature, population-of-origin, and vgll3 genotype on maturation in 2-year-old male Atlantic salmon (Salmo salar). With a temperature difference of 1.8°C, maturation probability was 4.8 times higher in the warm treatment than the cold treatment. This temperature effect was population-specific and was higher in the southern (60.48°N) compared to the northern (65.01°N) population. The early maturation vgll3*E allele was associated with a significantly higher maturation probability, but there was no vgll3 interaction with temperature or population. Both body condition and body mass associated with maturation. The body mass association was only present in the warm treatment. Our findings demonstrate that (i) populations can vary in their response to temperature change in terms of age at maturity, (ii) high intrinsic growth could be associated with higher thermal sensitivity for life history variation and (iii) vgll3 effects on age at maturity might be similar between populations and different thermal environments.

13.
J Biomed Mater Res A ; 111(8): 1228-1242, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36762538

RESUMEN

There is a growing interest in creating 2D cardiac tissue models that display native extracellular matrix (ECM) cues of the heart tissue. Cellular alignment alone is known to be a crucial cue for cardiac tissue development by regulating cell-cell and cell-ECM interactions. In this study, we report a simple and robust approach to create lamellar surface wrinkling patterns enabling spatial control of pattern dimensions with a wide range of pattern amplitude (A ≈ 2-55 µm) and wavelength (λ ≈ 35-100 µm). For human cardiomyocytes (hCMs) and human cardiac fibroblasts (hCFs), our results indicate that the degree of cellular alignment and pattern recognition are correlated with pattern A and λ. We also demonstrate fabrication of devices composed of micro-well arrays with user-defined lamellar patterns on the bottom surface of each well for high-throughput screening studies. Results from a screening study indicate that cellular alignment is strongly diminished with increasing seeding density. In another study, we show our ability to vary hCM/hCF seeding ratio for each well to create co-culture systems where seeding ratio is independent of cellular alignment.


Asunto(s)
Matriz Extracelular , Miocitos Cardíacos , Humanos , Técnicas de Cocultivo , Células Cultivadas , Matriz Extracelular/metabolismo , Fibroblastos , Ingeniería de Tejidos/métodos
14.
J Fish Biol ; 102(5): 1096-1108, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36647775

RESUMEN

The environment experienced by a female influences reproductive traits in many species of fish. Environmental factors such as temperature and diet are not only important mediators of female maturation and reproduction but also of egg traits and offspring fitness through maternal provisioning. In this study, we use 3-year-old tank-reared Atlantic salmon from two Finnish populations to investigate the effect of temperature and diet on maturation and egg traits. We show that a temperature difference of 2°C is sufficient to delay maturation in female Atlantic salmon whereas a 22% reduction in dietary energy content had no effect on maturation. Diet did not influence the body size, condition or fecundity of the mature females or the size or protein content of the eggs. However, a higher energy diet increased egg lipid content. Neither female body size nor condition were associated with egg size or fat/protein composition. Our results indicate that female salmon that have a poorer diet in terms of energy content may have a reproductive disadvantage due to the lower energy provisioning of eggs. This disadvantage has the potential to translate into fitness consequences for their offspring.


Asunto(s)
Salmo salar , Animales , Femenino , Temperatura , Reproducción , Fertilidad , Dieta/veterinaria
16.
Sci Rep ; 12(1): 20236, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36424380

RESUMEN

Severe COVID-19 infection results in significant immune dysregulation resulting from excessive recruitment and activation of neutrophils. The aim of this study was to confirm feasibility, initial safety and detect signal of efficacy of a non-propriety device delivered using an intermittent extra-corporeal system (LMOD) allowing leucocytes modulation in the setting of Severe COVID-19 infection. Twelve patients were recruited. Inclusion criteria were > 18 years age, confirmed COVID-19, acute respiratory distress syndrome requiring mechanical support and hypotension requiring vasopressor support. Primary end point was vasopressor requirements (expressed as epinephrine dose equivalents) and principle secondary endpoints related to safety, ability to deliver the therapy and markers of inflammation assessed over five days after treatment initiation. LMOD treatment appeared safe, defined by hemodynamic stability and no evidence of white cell number depletion from blood. We demonstrated a significant decrease in vasopressor doses (-37%, p = 0.02) in patients receiving LMOD therapy (despite these patients having to tolerate an additional extracorporeal intermittent therapy). Vasopressor requirements unchanged/increasing in control group (+ 10%, p = 0.48). Although much about the use of this therapy in the setting of severe COVID-19 infection remains to be defined (e.g. optimal dose and duration), this preliminary study supports the further evaluation of this novel extracorporeal approach.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Oxigenación por Membrana Extracorpórea , Síndrome de Dificultad Respiratoria , Humanos , Enfermedad Crítica , Oxigenación por Membrana Extracorpórea/métodos , Inmunomodulación , Vasoconstrictores/uso terapéutico
17.
J Cell Sci ; 135(16)2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35851804

RESUMEN

Fibronectin (Fn1) fibrils have long been viewed as continuous fibers composed of extended, periodically aligned Fn1 molecules. However, our live-imaging and single-molecule localization microscopy data are inconsistent with this traditional view and show that Fn1 fibrils are composed of roughly spherical nanodomains containing six to eleven Fn1 dimers. As they move toward the cell center, Fn1 nanodomains become organized into linear arrays, in which nanodomains are spaced with an average periodicity of 105±17 nm. Periodical Fn1 nanodomain arrays can be visualized between cells in culture and within tissues; they are resistant to deoxycholate treatment and retain nanodomain periodicity in the absence of cells. The nanodomain periodicity in fibrils remained constant when probed with antibodies recognizing distinct Fn1 epitopes or combinations of antibodies recognizing epitopes spanning the length of Fn1. Treatment with FUD, a peptide that binds the Fn1 N-terminus and disrupts Fn1 fibrillogenesis, blocked the organization of Fn1 nanodomains into periodical arrays. These studies establish a new paradigm of Fn1 fibrillogenesis. This article has an associated First Person interview with the first author of the paper.


Asunto(s)
Fibronectinas , Microscopía , Epítopos , Matriz Extracelular/metabolismo , Fibronectinas/metabolismo , Péptidos/metabolismo
19.
Can J Kidney Health Dis ; 9: 20543581221100292, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35615071

RESUMEN

Purpose of Program: We initiated the Renal Community Photo Initiative to better understand why some hemodialysis users express significant capacities for resilience and hope, demonstrating outward-looking perspectives and enjoying a rich quality of life. Sources of Information: "Photovoice" is a participatory research methodology that encourages individuals to develop positive self-perceptions with photography. Photovoice empowers participants as informants within their communities. Visual arts researchers surveyed existing Photovoice studies to identify gaps in knowledge to be addressed in this study, including challenges related to fostering participant agency and social action. Images and logs were collected and reviewed during organized, participant-led substudy groups. These meetings provided researchers with core study values and direction as to how the images and additional information should be used to raise awareness about living with chronic kidney disease. Methods: To address the complexity of the human condition, the Renal Community Photo Initiative offered participants an array of diverse and accessible image-making techniques. No narrative directives for image-making were provided. This qualitative, interdisciplinary, participant-centric study invited adult chronic hemodialysis patients in 4 dialysis units in London and Stratford, Ontario, to participate. The research team designed a selection of different, accessible photo technologies for participant use. Eligible participants were invited to select photographic technologies and given the additional option to write accompanying logs. Researchers organized substudy meetings for participant-led focus groups to discuss core study values and personal encounters with images and image-making. Participants directed how their generated images should be shared with the public and researchers. Key Findings: A total of 40 participants have been recruited to date, producing more than 1600 images and an archive of handwritten logs. Three participant-led focus groups have established priorities for image sharing and a core set of values for subsequent study phases. A series of public presentations of participant images took place. The research team will pursue further public presentation opportunities and the development of a suitable research database. Limitations: Organizing and categorizing images for access in an interdisciplinary research database remains a challenge. Current health and safety protocols related to COVID-19 require the study to pause recruitment and substudy meetings and reassess immediate outputs for visuals. Implications: A qualitative study of this scope offers a new model for participant agency and collaboration. It requires the onboarding of interdisciplinary researchers to effectively engage with its significant image and log archive. Participants should remain involved in directing future steps for disseminating their images. Following substudy directives, researchers are developing visuals for health care and public settings, and determining opportunities for participants to share their experience in both clinic- and public-based settings.


Objectif du programme: Nous avons lancé la Renal Community Photo Initiative afin de mieux comprendre pourquoi certains utilisateurs de l'hémodialyse font preuve d'importantes capacités de résilience et d'espoir, sont tournés vers le monde extérieur et jouissent d'une riche qualité de vie. Sources: « Photovoice ¼ est une méthodologie de recherche participative qui encourage les individus à développer une perception de soi positive grâce à la photographie. Photovoice permet aux participants de devenir des informateurs au sein de leurs communautés. Les chercheurs en arts visuels ont mené une enquête sur les études existantes de Photovoice afin de révéler les lacunes dans les connaissances qui pourraient être comblées par la présente étude, notamment les défis liés à la promotion de la participation et de l'action sociale des participants. Des images et des registres ont été recueillis et examinés lors de sous-groupes d'étude organisés et dirigés par les participants par les participants. Ces réunions ont permis aux chercheurs de définir les valeurs fondamentales de l'étude et d'indiquer comment utiliser les images et les autres informations pour sensibiliser les gens à la vie avec maladie rénale chronique. Méthodologie: Afin d'aborder la complexité de la condition humaine, la Renal Community Photo Initiative a offert aux participants une gamme diverse et accessible de techniques de création d'images. Aucune directive narrative n'a été fournie pour la création des images. Cette étude qualitative, interdisciplinaire et axée sur les participants a invité des adultes suivant des traitements d'hémodialyse chronique dans quatre unités de dialyse de London et Stratford (Ontario) à participer. L'équipe de recherche a conçu une sélection de technologies photographiques diverses et accessibles à l'usage des participants. Les participants admissibles ont été invités à choisir des technologies photographiques et à tenir un journal s'ils le souhaitaient. Les chercheurs ont organisé des réunions de sous-étude pour des groupes de discussion dirigés par les participants afin de discuter des valeurs fondamentales de l'étude et des expériences personnelles avec les images et la création d'images. Les participants ont établi la façon dont leurs images devraient être partagées avec le public et les chercheurs. Principaux résultats: À ce jour, 40 participants ont été recrutés et plus de 1 600 images ont été produites, de même qu'une archive de journaux manuscrits. Trois groupes de discussion dirigés par les participants ont établi les priorités pour le partage des images ainsi qu'un ensemble de valeurs fondamentales en vue des phases ultérieures de l'étude. Plusieurs présentations publiques des images des participants ont eu lieu. L'équipe de recherche poursuivra les présentations publiques et l'élaboration d'une base de données de recherche. Limites: L'organisation et la catégorisation des images pour y accéder dans une base de données de recherche interdisciplinaire demeurent un défi. Les protocoles actuels de santé et de sécurité liés à la COVID-19 empêchent le recrutement et les réunions de sous-étude pour le moment et imposent de réévaluer les résultats immédiats pour les visuels. Conclusion: Une étude qualitative de cette envergure offre un nouveau modèle pour la participation et collaboration des patients. Elle exige l'intégration de chercheurs interdisciplinaires afin d'exploiter efficacement ses importantes archives d'images et de journaux. Il importe que les participants demeurent impliqués dans la direction des prochaines étapes de diffusion de leurs images. Suivant les directives de la sous-étude, les chercheurs développent des visuels pour les soins de santé et les milieux publics, et recensent les occasions pour les participants de partager leur expérience tant dans les milieux cliniques que publics.

20.
J Am Soc Nephrol ; 33(6): 1182-1192, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35321940

RESUMEN

BACKGROUND: Patients with kidney transplant failure have a high risk of hospitalization and death due to infection. The optimal use of immunosuppressants after transplant failure remains uncertain and clinical practice varies widely. METHODS: This prospective cohort study enrolled patients within 21 days of starting dialysis after transplant failure in 16 Canadian centers. Immunosuppressant medication use, death, hospitalized infection, rejection of the failed allograft, and anti-HLA panel reactive antibodies were determined at 1, 3, 6, and 12 months and and then twice yearly until death, repeat transplantation, or loss to follow-up. RESULTS: The 269 study patients were followed for a median of 558 days. There were 33 deaths, 143 patients hospitalized for infection, and 21 rejections. Most patients (65%) continued immunosuppressants, 20% continued prednisone only, and 15% discontinued all immunosuppressants. In multivariable models, patients who continued immunosuppressants had a lower risk of death (hazard ratio [HR], 0.40; 95% confidence interval [CI], 0.17 to 0.93) and were not at increased risk of hospitalized infection (HR, 1.81; 95% CI, 0.82 to 4.0) compared with patients who discontinued all immunosuppressants or continued prednisone only. The mean class I and class II panel reactive antibodies increased from 11% to 27% and from 25% to 47%, respectively, but did not differ by immunosuppressant use. Continuation of immunosuppressants was not protective of rejection of the failed allograft (HR, 0.81; 95% CI, 0.22 to 2.94). CONCLUSIONS: Prolonged use of immunosuppressants >1 year after transplant failure was not associated with a higher risk of death or hospitalized infection but was insufficient to prevent higher anti-HLA antibodies or rejection of the failed allograft.


Asunto(s)
Trasplante de Riñón , Insuficiencia Renal , Aloinjertos , Canadá , Estudios de Cohortes , Rechazo de Injerto/prevención & control , Supervivencia de Injerto , Humanos , Inmunosupresores/uso terapéutico , Riñón , Trasplante de Riñón/efectos adversos , Prednisona/uso terapéutico , Estudios Prospectivos , Insuficiencia Renal/etiología
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