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M Ballester

Publications and source records attributed to M Ballester.

18 recordsLinked to original sources
PubMed2026

Exploring genomic regions regulating the liver transcriptome and energy homeostasis in pigs.

In pigs, energy homeostasis has an impact on meat quality and health. In a Duroc pig population, 30 quantitative trait locus (QTL) regions associated with fatty acid (FA) composition in adipose tissue, plasma, liver and muscle were previously identified. Mapping of expression quantitative trait locus (eQTL) regions will provide a molecular hypothesis for genotype-phenotype interactions and may allow the identification of shared causal variants, key to increasing our understanding of the genetic regulation of FA composition and energy homeostasis. However, gene expression is impacted by environmental factors, while individual-level allelic imbalance (AI) can be more reliable and can be surveyed via allelic-specific expression (ASE) analysis. Furthermore, treatment of ASE as a quantitative trait allows the identification of allele-specific expression quantitative trait loci (aseQTLs), which are variants whose heterozygosity is linked to the AI of a nearby single-nucleotide polymorphism (SNP), pointing to regulatory elements. In this study, liver was selected as a key metabolic hub with an important role in the regulation of energy homeostasis, and 310 liver RNA sequencing samples were analysed using a combination of (1) eQTL mapping, (2) ASE analysis, and (3) aseQTL mapping methods. A total of 2 188 eQTL regions were identified, mostly cis-eQTL regions (73.17%). ASE analysis reported 1 964 ASE SNPs, associated with 633 genes. Finally, aseQTL mapping reported 64 172 aseQTL, associated with the AI of 31 genes. Colocalisation analysis combined with ASE analysis showed that the expression of FADS1 and FADS2 genes is associated with the polyunsaturated FA composition in several tissues, where microRNA regulation may be present. Finally, in the DGAT2 gene, annotated in a QTL region associated with multiple FAs in adipose tissue, ASE revealed allelic imbalance in the 3' untranslated region (UTR) of this gene. Allelic differential expression can be caused by a 13-bp insertion affecting messenger RNA stability, previously described, exemplifying how allelic imbalance is caused by a post-transcriptional regulatory mechanism undetectable by eQTL mapping. Furthermore, aseQTLs were associated with this gene, linked to a previously identified copy number variant not yet associated with DGAT2 expression. These results demonstrate how ASE analysis and aseQTL mapping can complement eQTL mapping, as they resolved a complex region affected by allelic heterogeneity, a main confounding effect of QTL mapping. In conclusion, the combination of eQTL mapping, ASE analysis and aseQTL mapping allowed the characterisation of the regulation of liver gene expression, improving our understanding of the genetic determinism of energy homeostasis.

Allele-specific expression↗
PubMed2026

Enterococcus faecalis GP1764 induces an early differential gene expression in the intestine on key pathways related to cellular immune response and gut barrier function in chickens.

The aim of the present study was to elucidate the mode of action of Enterococcus faecalis GP1764 in improving performance traits during the starter phase by analyzing genome-wide gene expression and its interaction with microbial populations in the intestine of chickens challenged with an NSP-rich diet. At day 7, microbiota populations from ileal and cecal contents and transcriptomics from jejunal and cecal mucosa were analyzed between Control (Ctrl) and Enterococcus faecalis GP1764 (EntF) groups. Results from microbiota analysis demonstrated that EntF shifted β-diversity indices in ileum (neutral (p= 0.006) and phylogenetic (p= 0.006)) and caecum (phylogenetic (p= 0.017)). Transcriptomics revealed 43 differentially expressed genes for EntF vs. Ctrl in the jejunal mucosa. Of these, MHCY-36 (MHC-I-Related), RAG2 and MUC19-like genes were upregulated in EntF vs. Ctrl, protein-coding genes with immunomodulatory capacities as supported by GSEA and Cytoscape-ClueGo pathway analyses. Results suggest an intestinal immunomodulation induced through presentation of B vitamins metabolites, synthetized by EntF, to an undescribed subset of innate-like unconventional T lymphocytes in chickens, similar to MAIT cells in mammals. These cells could contribute to antibacterial responses and repair of damaged barrier tissue after inflammatory processes. The upregulation of the MUC19-like gene expression observed in the jejunal mucosa can protect gut integrity via the promotion of mucus production by goblet cells. Finally, RAG2, involved in V(D)J coding segments recombination in B- and T-cells may provide a greater recognition of foreign invaders, allowing the animals to efficiently fight against pathogenic infections. Collectively, these results suggest an important role of EntF in promoting the capacity of animals to rapidly act against pathogenic challenges, herein, inducing resilience towards dietary ingredients with anti-nutritional activity that impart moderate inflammation in chickens.

Enterococcus faecalis↗
PubMed1992

Early postoperative reduction of monoclonal antimyosin antibody uptake is associated with absent rejection-related complications after heart transplantation.

BACKGROUND: Detection and treatment for rejection after transplantation are based on the identification of myocyte damage upon endomyocardial biopsy. Noninvasive detection of such damage is possible with 111In-labeled monoclonal antimyosin antibodies (MAA). Although the presence and degree of MAA uptake parallels the rejection activity detected by biopsy, the relation between the degree of uptake and the occurrence of severe rejection-related complications has not been previously assessed. METHODS AND RESULTS: Two hundred forty-seven MAA studies were performed coinciding with biopsies in 52 patients 1-71 months after transplantation. A heart-to-lung ratio (HLR) was used as a measure of relative MAA uptake, with an HLR of 1.55 discriminating normal from abnormal studies. Of the 247 antimyosin studies, 149 coincided with absent, 38 with mild, and 60 with moderate rejection at biopsy. HLR was 1.68 +/- 0.27, 1.79 +/- 0.22, and 1.91 +/- 0.33 in the three biopsy groups, respectively (p less than 0.0001). Two hundred thirty-eight of 247 antimyosin studies coexisted with absent rejection-related complications; in nine of 247 patients, such complications were detected (five congestive heart failure episodes due to rejection and four episodes of vascular occlusion, which resulted in five deaths), and mean HLR was 1.74 +/- 0.3 and 2.1 +/- 0.16 in the two groups, respectively (p less than 0.0001). No complications were noted in 193 studies of patients with HLR of less than 2.00, whereas in nine of 45 with HRL of 2.00 or greater, complications occurred (p less than 0.0001). None of the 23 patients prospectively followed since surgery who had a gradual decrease in MAA uptake during the first 3 months showed rejection-related complications, whereas persistent uptake was associated with complications in five of nine patients (p less than 0.001). CONCLUSIONS: No rejection-related complications are seen coinciding with HLR of less than 2.00, whereas patients who have complications have an HLR of more than 2.00. The early 3-month pattern of decreasing MAA uptake is associated with a clinical course free of rejection-related complications, whereas a persistent pattern is a signal of the possibility of such complications.

Adult↗
PubMed1991

Recovery of sinus node function after pacemaker implant for sinus node disease following cardiac transplantation.

In a 4-year interval, 3/55 (7.8%) heart transplant recipients developed (greater than 4 weeks) severe sinus node dysfunction. An epicardial ventricular pacemaker was implanted at 90, 40, and 38 days after operation. Follow-up ranged from 7 to 20 months. In two of the three cases, failure of stimulation or sensing was detected at the 3rd and 4th month after pacemaker implantation. Sinus rhythm reappeared in two of the three patients at the 2nd and 4th months after transplantation. Severe sinus node disease requiring pacemaker implantation can improve following the first 3 months after transplantation. Failure of stimulation or sensing may not be uncommon.

Adult↗
PubMed1990

Indium-111-monoclonal antimyosin antibody studies after the first year of heart transplantation. Identification of risk groups for developing rejection during long-term follow-up and clinical implications.

The long-term clinical course and results of biopsies in 21 patients studied with monoclonal antimyosin antibodies more than 12 months after heart transplantation according to the presence and degree of antimyosin-antibody uptake is described. Eighteen men and three women aged 20-52 years (39 +/- 9 years) were studied with antimyosin antibodies 12-40 months (mean, 22 +/- 9 months) after heart transplantation, and followed for a mean of 18 months (10-28 months). The number of biopsies performed during follow-up was 102. Results showed normal antimyosin-antibody studies in nine patients and abnormal studies in 12 patients. Myocyte damage was identified in 18 of the 102 biopsies (17.6%), one in the normal antimyosin-antibody group of patients and 17 in those patients with myocardial antimyosin-antibody uptake. Patients who developed rejection comprised 11% and 67% of each respective group; the mean number of rejection episodes per patient was 0.11 +/- 0.33 and 1.41 +/- 1.41, respectively (p less than 0.01). A trend was noted by which higher heart-to-lung ratios were associated with greater probability of rejection. Conclusively, 1) antimyosin-antibody studies performed after more than 1 year after heart transplantation indicate the presence and level of rejection activity, 2) groups of patients at risk for developing rejection at biopsy during long-term follow-up may be detected by antimyosin-antibody study, and 3) surveillance for rejection and the degree of immunosuppression should be tailored to meet individual patient needs.

Adult↗
PubMed1989

Dopamine treatment of locally procured donor hearts: relevance on postoperative cardiac histology and function.

UNLABELLED: Administration of catecholamines can lead to myocyte damage. Dopamine treatment is often used in potential cardiac donors to attain hemodynamic stability. Donor hearts exposed to dopamine are rejected or selected for transplantation without clearly defined criteria. A prospective study was undertaken to analyze the clinical relevance of dopamine-induced myocardial lesions in 25 hearts (21 male, 4 female; 15-40 years, mean: 26 +/- 7) that were later used for transplantation. Donors were divided into those who had received dopamine and those who had not. Dopamine doses ranged from 2-12.5 micrograms/kg/min (mean: 6.3 +/- 3). Time of administration was 3-26 hours (mean: 16 +/- 8). Use of dopamine was unrelated to donor electrocardiographic findings, intra- or postoperative death, or difficulty coming off by-pass. Postoperatively, filling pressures were similar in both groups of patients at 2 and 10 days postoperatively. Left ventricular ejection fraction was similar in the two groups. Dopamine requirements were significantly higher in the dopamine-treated hearts (P = 0.05). Histologic findings at first biopsy revealed infiltration and cell damage in a similar proportion of patients in both groups. IN CONCLUSION: donor hearts exposed to dopamine can be accepted for transplantation if doses ranging from 2-12.5 micrograms/kg/min have been administered up to 24 hours.

Adolescent↗
PubMed1989

High prevalence of myocardial monoclonal antimyosin antibody uptake in patients with chronic idiopathic dilated cardiomyopathy.

Monoclonal antimyosin antibody studies were undertaken to assess the presence of myocardial uptake in patients with chronic idiopathic dilated cardiomyopathy. Three groups were studied: 17 patients with chronic (greater than 12 months) idiopathic dilated cardiomyopathy, 12 patients with a large, poorly contracting left ventricle not due to dilated cardiomyopathy (control patients) and 8 normal individuals. The patients in the cardiomyopathy and control groups showed a similar degree of clinical and functional impairment. Imaging was undertaken 48 h after antimyosin injection. The heart/lung ratio of antimyosin uptake was used to assess the results. The mean ratio in the cardiomyopathy group was 1.83 +/- 0.36 (range 1.40 to 2.80), a value significantly higher than that obtained in the control patients without cardiomyopathy (mean 1.46 +/- 0.04, range 1.38 to 1.50) or normal subjects (mean 1.46 +/- 0.13, range 1.31 to 1.6) (p less than 0.01). No difference in the ratio was noted between the normal subjects and control patients. Abnormal antimyosin uptake was seen in 12 (70%) of the 17 patients with cardiomyopathy and in only 1 (8%) of the 12 control patients. Positive monoclonal antimyosin antibody studies are highly prevalent in chronic idiopathic dilated cardiomyopathy.

Adult↗
PubMed1979

[Clinical course characteristics of polymyalgia arteritica. Study of 16 cases].

Clinical and biological characteristics are studied in 16 patients with polymyalgia arteritica. 12 of them were diagnosed by biopsy of the temporal artery and the other 4 because they presented clinical, biological data and a high response to corticosteroids. There were no differences according to sex. Most patients (75%) had symptoms since 1-6 months, headache being the most common (75%). Fever (56%), polymyalgia (50%), weight loss (37%), intermittent claudication, loss of vision and arthritis (12%) were the symptoms seen in these patients. ERS was high in all cases, hemoglobin was less than 8 g/100 ml in 8 cases and an increase of alfa-2-globuline was found in 8 patients. Temporal artery palpation was abnormal in 11 patients. Two of 5 patients who presented a normal arterial palpation had a positive biopsy. All patients received 6-metil-prednisolone. 3 are well after 3, 4 and 6 months therapy. 8 are also well but receiving small doses of steroids as treatment.

Aged↗
PubMedDate not supplied

Reversal of rejection-induced coronary vasculitis detected early after heart transplantation with increased immunosuppression.

Four patients who underwent heart transplantation, in whom coronary obstruction was seen early after transplantation, are described. Repeated acute rejection episodes were detected within the first 2 months in each patient. Coronary obstruction or ischemia was shown through a combination of T1-201 isotopic study findings, evidence of vasculitis of a small coronary arteriole seen at endomyocardial biopsy, or coronary angiographic results. Vigorous treatment for rejection (antithymocyte globulin and bolus methylprednisolone) was given, and coronary artery lesions or myocardial ischemia resolved after treatment. Rejection-induced coronary obstruction should be considered in patients with repeated acute rejection episodes who are predisposed to the development of vascular rejection. Early after transplantation such obstruction is caused by diffuse vasculitis of small and medium-sized vessels and may be reversed with increased immunosuppression.

Adult↗
PubMedDate not supplied

[Viridicine: a bacteriocine from "Aerococcus viridans" (author's transl)].

Viridicine, a new bacteriocine, was extracted from whole cells of Aerococcus viridans by repeated washings with Tris-HCl 5 X 10(-3) M pH 8,1, NaCl 1 M. A crude preparation of the macromolecule was not inactived by heating for one hour at 50 degrees C and was sensitive to the action of protease, lipase and catalase. The molecular weight was about 100,000. A large number of Gram-negative and Gram-positive bacteria were sensitive to viridicine action.

Bacteria↗