Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
19
result(s) for
"Navasa, Miquel"
Sort by:
A plasmatic score using a miRNA signature and CXCL-10 for accurate prediction and diagnosis of liver allograft rejection
2023
The use of noninvasive biomarkers may avoid the need for liver biopsy (LB) and could guide immunosuppression adjustment in liver transplantation (LT). The aims of this study were: to confirm the predictive and diagnostic capacity of plasmatic expression of miR-155-5p, miR-181a-5p, miR-122-5p and CXCL-10 for assessing T-cell mediated rejection (TCMR) risk; to develop a score based on a panel of noninvasive biomarkers to predict graft rejection risk and to validate this score in a separate cohort.
A prospective, observational study was conducted with a cohort of 79 patients followed during the first year after LT. Plasma samples were collected at predetermined time points for the analysis of miRNAs and the CXCL-10. Patients with LFTs abnormalities were submitted to a LB to rule out rejection, assessing previous and concurrent expression of the biomarkers to evaluate their predictive and diagnostic ability. Information from 86 patients included in a previous study was collected and used as a validation cohort.
Twenty-four rejection episodes were diagnosed in 22 patients. Plasmatic CXCL-10 concentration and the expression of the three miRNAs were significantly elevated prior to and at the moment of the diagnosis of rejection. We developed a logistic model for rejection prediction and diagnosis, which included CXCL-10, miR-155-5p and miR-181a-5p. The area under the ROC curve (AUROC) for rejection prediction was 0.975 (79.6% sensitivity, 99.1% specificity, 90,7% PPV; 97.7% NPV; 97.1% correctly classified) and 0.99 for diagnosis (87.5% sensitivity, 99.5% specificity, 91.3% PPV; 99.3% NPV; 98.9% correctly classified). In the validation cohort (n=86; 14 rejections), the same cut-off points were used obtaining AUROCs for rejection prediction and diagnosis of 0.89 and 0.92 respectively. In patients with graft dysfunction in both cohorts the score could discriminate those with rejection regarding other causes with an AUROC of 0.98 (97.3% sensitivity, 94.1%specificity).
These results suggest that the clinical implementation of the monitoring of this noninvasive plasmatic score may allow the prediction and diagnosis of rejection and identify patients with graft dysfunction due to rejection, helping with a more efficient guide for immunosuppressive therapy adjustment. This finding warrants the development of prospective biomarker-guided clinical trials.
Journal Article
Modeling hepatitis C virus kinetics during liver transplantation reveals the role of the liver in virus clearance
2021
While the liver, specifically hepatocytes, are widely accepted as the main source of hepatitis C virus (HCV) production, the role of the liver/hepatocytes in clearance of circulating HCV remains unknown. Frequent HCV kinetic data were recorded and mathematically modeled from five liver transplant patients throughout the anhepatic (absence of liver) phase and for 4 hr post-reperfusion. During the anhepatic phase, HCV remained at pre-anhepatic levels ( n = 3) or declined ( n = 2) with t 1/2 ~1 hr. Immediately post-reperfusion, virus declined in a biphasic manner in four patients consisting of a rapid decline ( t 1/2 = 5 min) followed by a slower decline ( t 1/2 = 67 min). Consistent with the majority of patients in the anhepatic phase, when we monitored HCV clearance at 37°C from culture medium in the absence/presence of chronically infected hepatoma cells that were inhibited from secreting HCV, the HCV t 1/2 in cell culture was longer in the absence of chronically HCV-infected cells. The results suggest that the liver plays a major role in the clearance of circulating HCV and that hepatocytes may be involved.
Journal Article
Molecular characterization of multidrug resistant Enterobacterales strains isolated from liver and kidney transplant recipients in Spain
by
Fariñas, Maria Carmen
,
Fernández-Martínez, Marta
,
Martínez-Martínez, Luis
in
631/326
,
631/326/107
,
631/326/22
2021
The objective of this study was to analyse the mechanisms of resistance to carbapenems and other extended-spectrum-β-lactams and to determine the genetic relatedness of multidrug-resistant
Enterobacterales
(MDR-E) causing colonization or infection in solid-organ transplantation (SOT) recipients. Prospective cohort study in kidney (n = 142), liver (n = 98) or kidney/pancreas (n = 7) transplant recipients between 2014 and 2018 in seven Spanish hospitals. We included 531 MDR-E isolates from rectal swabs obtained before transplantation and weekly for 4–6 weeks after the procedure and 10 MDR-E from clinical samples related to an infection. Overall, 46.2%
Escherichia coli
, 35.3%
Klebsiella pneumoniae
, 6.5%
Enterobacter cloacae
, 6.3%
Citrobacter freundii
and 5.7% other species were isolated. The number of patients with MDR-E colonization post-transplantation (176; 71.3%) was 2.5-fold the number of patients colonized pre-transplantation (71; 28.7%). Extended-spectrum β-lactamases (ESBLs) and carbapenemases were detected in 78.0% and 21.1% of MDR-E isolates respectively. In nine of the 247 (3.6%) transplant patients, the microorganism causing an infection was the same strain previously cultured from surveillance rectal swabs. In our study we have observed a low rate of MDR-E infection in colonized patients 4–6 weeks post-transplantation.
E. coli
producing
bla
CTX-M-G1
and
K. pneumoniae
harbouring
bla
OXA-48
alone or with
bla
CTX-M-G1
were the most prevalent MDR-E colonization strains in SOT recipients.
Journal Article
A Metabolomics Signature Linked To Liver Fibrosis In The Serum Of Transplanted Hepatitis C Patients
by
Embade, Nieves
,
Mato, José María
,
Bosch, Jaume
in
631/45/287
,
631/61/320
,
692/4020/4021/234/2513/1551
2017
Liver fibrosis must be evaluated in patients with hepatitis C virus (HCV) after liver transplantation because its severity affects their prognosis and the recurrence of HCV. Since invasive biopsy is still the gold standard to identify patients at risk of graft loss from rapid fibrosis progression, it becomes crucial the development of new accurate, non-invasive methods that allow repetitive examination of the patients. Therefore, we have developed a non-invasive, accurate model to distinguish those patients with different liver fibrosis stages. Two hundred and three patients with HCV were histologically classified (METAVIR) into five categories of fibrosis one year after liver transplantation. In this cross-sectional study, patients at fibrosis stages F0-F1 (n = 134) were categorised as “slow fibrosers” and F2-F4 (n = 69) as “rapid fibrosers”. Chloroform/methanol serum extracts were analysed by reverse ultra-high performance liquid chromatography coupled to mass spectrometry. A diagnostic model was built through linear discriminant analyses. An algorithm consisting of two sphingomyelins and two phosphatidylcholines accurately classifies rapid and slow fibrosers after transplantation. The proposed model yielded an AUROC of 0.92, 71% sensitivity, 85% specificity, and 84% accuracy. Moreover, specific bile acids and sphingomyelins increased notably along with liver fibrosis severity, differentiating between rapid and slow fibrosers.
Journal Article
Implementation of a quality management system in a liver transplant programme
2023
BackgroundThe management of liver transplantation has become a complex process involving different healthcare professionals. Teamwork, standardisation and definition of the best practices are essential for success, patient satisfaction and society’s favourable perception of transplantation programmes.ISO 9001:2015 certification provides the necessary elements to help implement a quality management system (QMS) to ensure that patient care is performed with the highest guarantees of clinical quality and safety. The aim of this study is to describe the steps, strengths and limitations in the implementation of a QMS in a liver transplant programme (LTP).Project management methodThis included analysing the starting point, setting up a working group, training, defining the scope of certification, preparing documentation, and conducting an internal and external audit, which culminated in the ISO 9001 quality certification award. The scope of QMS includes all the processes of LTP, from referral of candidates to long-term follow-up after transplantation.ResultsThe project was structured in seven phases that took place between 2008 and 2011. The implementation of QMS led to the generation of all the necessary documentation to meet the requirements of the standard, including internal and legal requirements related to the transplant activity. The establishment of indicators to measure the effectiveness of processes, risk management and the identification of incidents allows us to implement measures devoted to avoiding the deficiencies and to meet the established objectives.ConclusionISO 9001:2015 certification has contributed to the adaptation of a new quality and safety culture focused on the patient. All activities are protocolised, everything is recorded, measured, and verified, and all steps are taken as planned. Work is carried out in terms of continuous improvement. This has led to less variability in daily clinical practice and a better understanding of work dynamics.
Journal Article
Lack of a 5.9 kDa Peptide C-Terminal Fragment of Fibrinogen α Chain Precedes Fibrosis Progression in Patients with Liver Disease
by
Casals, Gregori
,
Morales-Ruiz, Manuel
,
Jiménez, Wladimiro
in
Alcoholism
,
Biochemistry
,
Biology and Life Sciences
2014
Early detection of fibrosis progression is of major relevance for the diagnosis and management of patients with liver disease. This study was designed to find non-invasive biomarkers for fibrosis in a clinical context where this process occurs rapidly, HCV-positive patients who underwent liver transplantation (LT). We analyzed 93 LT patients with HCV recurrence, 41 non-LT patients with liver disease showing a fibrosis stage F≥1 and 9 patients without HCV recurrence who received antiviral treatment before LT, as control group. Blood obtained from 16 healthy subjects was also analyzed. Serum samples were fractionated by ion exchange chromatography and their proteomic profile was analyzed by SELDI-TOF-MS. Characterization of the peptide of interest was performed by ion chromatography and electrophoresis, followed by tandem mass spectrometry identification. Marked differences were observed between the serum proteome profile of LT patients with early fibrosis recurrence and non-recurrent LT patients. A robust peak intensity located at 5905 m/z was the distinguishing feature of non-recurrent LT patients. However, the same peak was barely detected in recurrent LT patients. Similar results were found when comparing samples of healthy subjects with those of non-LT fibrotic patients, indicating that our findings were not related to either LT or HCV infection. Using tandem mass-spectrometry, we identified the protein peak as a C-terminal fragment of the fibrinogen α chain. Cell culture experiments demonstrated that TGF-β reduces α-fibrinogen mRNA expression and 5905 m/z peak intensity in HepG2 cells, suggesting that TGF-β activity regulates the circulating levels of this protein fragment. In conclusion, we identified a 5.9 kDa C-terminal fragment of the fibrinogen α chain as an early serum biomarker of fibrogenic processes in patients with liver disease.
Journal Article
Combinations of simple baseline variables accurately predict sustained virological response in patients with recurrent hepatitis C after liver transplantation
2013
Background
The efficacy of antiviral therapy in patients with hepatitis C recurrence after liver transplantation (LT) is far from optimal and a careful selection of candidates with the best chances to achieve sustained virological response (SVR) is relevant. Moreover, investigating the effects of sustained viral clearance on clinical outcomes is particularly significant. We aimed to identify and combine the best baseline predictors of SVR and to assess the clinical outcomes of antiviral therapy after LT.
Methods
We studied 144 hepatitis C virus (HCV)-infected LT recipients who underwent antiviral therapy following transplantation. Baseline predictors of SVR including donor and recipient interleukin IL28B (IL28B) rs12979860 genotype were evaluated, and the long-term effects of antiviral therapy on clinical outcomes were assessed.
Results
The presence of an IL28B CC genotype with either low viral load (VL), young donor age, or cyclosporine A (CsA)-based immunosuppression identified individuals with 69–80 % probabilities of SVR. In contrast, only 20 % of recipients with a CT/TT IL28B genotype and either high VL, old donor age, or non-CsA immunosuppression achieved an SVR (
p
= 0.004). Regarding clinical outcomes, the 5-year cumulative probability of graft loss was 2 % for the SVR patients and 48 % for non-responders (
p
< 0.001).
Conclusions
The use of simple combinations of baseline variables including IL28B polymorphisms identifies HCV-infected LT recipients with different probabilities of response to antiviral treatment. SVR is associated with improved clinical outcomes.
Journal Article
Bone Disease in Patients Awaiting Liver Transplantation. Has the Situation Improved in the Last Two Decades?
2013
In recent years, there has been speculation about the possibility of a reduction in the incidence of fractures after liver transplantation (LT) because of changes in the characteristics of candidates and the use of different immunosuppressive therapies. We analyzed the characteristics of LT candidates (CTC) and compared them with historical data from a group of LT candidate patients (HTC). Data from 60 CTC patients consecutively included in a screening program of metabolic bone disease were compared with data from 60 HTC patients prospectively evaluated between 1992 and 1993. In all patients, we analyzed the clinical and laboratory characteristics, bone mineral density (BMD) dual-energy X-ray absorptiometry, and skeletal fractures. Patients in the CTC group were older than patients in the HTC group. The CTC group had lower femoral neck
T
scores. No differences were observed between groups in the proportion of patients with osteoporosis (22 vs. 30 %,
p
=
ns) or fractures (36 vs. 33 %,
p
=
ns). The percentage of patients with normal BMD decreased from 38 to 20 %. 25(OH)D values were low in both groups. Only 7.5 % of the CTC patients received calcium and/or vitamin D supplementation. The prevalence of fractures among CTC patients was similar to that seen two decades ago. At present, candidates for LT are older and have lower femoral bone mass. Vitamin D deficiency remains frequent; however, calcium and/or vitamin D supplementation is uncommon.
Journal Article
Interplay between Basic Residues of Hepatitis C Virus Glycoprotein E2 with Viral Receptors, Neutralizing Antibodies and Lipoproteins
by
Dragun, Jakub
,
Pérez-del-Pulgar, Sofia
,
Mensa, Laura
in
Adaptation
,
Alanine
,
Amino Acid Motifs
2012
Positively-charged amino acids are located at specific positions in the envelope glycoprotein E2 of the hepatitis C virus (HCV): two histidines (H) and four arginines (R) in two conserved WHY and one RGERCDLEDRDR motifs, respectively. Additionally, the E2 hypervariable region 1 (HVR1) is rich in basic amino acids. To investigate the role(s) of these residues in HCV entry, we subjected to comparative infection and sedimentation analysis cell culture-produced (HCVcc, genotype 2a) wild type virus, a panel of alanine single-site mutants and a HVR1-deletion variant. Initially, we analyzed the effects of these mutations on E2-heparan sulfate (HS) interactions. The positive milieu of the HVR1, formulated by its basic amino acids (key residues the conserved H³⁸⁶ and R⁴⁰⁸), and the two highly conserved basic residues H⁴⁸⁸ and R⁶⁴⁸ contributed to E2-HS interactions. Mutations in these residues did not alter the HCVcc-CD81 entry, but they modified the HCVcc-scavenger receptor class B type I (SR-BI) dependent entry and the neutralization by anti-E2 or patients IgG. Finally, separation by density gradients revealed that mutant viruses abolished partially or completely the infectivity of low density particles, which are believed to be associated with lipoproteins. This study shows that there exists a complex interplay between the basic amino acids located in HVR1 and other conserved E2 motifs with the HS, the SR-BI, and neutralizing antibodies and suggests that HCV-associated lipoproteins are implicated in these interactions.
Journal Article
Metabolic Characterization of Advanced Liver Fibrosis in HCV Patients as Studied by Serum 1H-NMR Spectroscopy
2016
Several etiologies result in chronic liver diseases including chronic hepatitis C virus infection (HCV). Despite its high incidence and the severe economic and medical consequences, liver disease is still commonly overlooked due to the lack of efficient non-invasive diagnostic methods. While several techniques have been tested for the detection of fibrosis, the available biomarkers still present severe limitations that preclude their use in clinical diagnostics. Liver diseases have also been the subject of metabolomic analysis. Here, we demonstrate the suitability of 1H NMR spectroscopy for characterizing the metabolism of liver fibrosis induced by HCV. Serum samples from HCV patients without fibrosis or with liver cirrhosis were analyzed by NMR spectroscopy and the results were submitted to multivariate and univariate statistical analysis. PLS-DA test was able to discriminate between advanced fibrotic and non-fibrotic patients and several metabolites were found to be up or downregulated in patients with cirrhosis. The suitability of the most significantly regulated metabolites was validated by ROC analysis. Our study reveals that choline, acetoacetate and low-density lipoproteins are the most informative biomarkers for predicting cirrhosis in HCV patients. Our results demonstrate that statistical analysis of 1H-NMR spectra is able to distinguish between fibrotic and non-fibrotic patients suffering from HCV, representing a novel diagnostic application for NMR spectroscopy.
Journal Article