Incidence and prognostic impact of U2AF1 mutations and other gene alterations in myelodysplastic neoplasms with isolated 20q deletion.

BACKGROUND: In myelodysplastic neoplasms (MDS), the 20q deletion [del(20q)] is a recurrent chromosomal abnormality that it has a high co-occurrence with U2AF1 mutations. Nevertheless, the prognostic impact of U2AF1 in these MDS patients is uncertain and the possible clinical and/or prognostic differences between the mutation type and the mutational burden are also unknown. METHODS: Our study analyzes different molecular variables in 100 MDS patients with isolated del(20q). RESULTS & CONCLUSIONS: We describe the high incidence and negative prognostic impact of U2AF1 mutations and other alterations such as in ASXL1 gene to identify prognostic markers that would benefit patients to receive earlier treatment.

Heparin versus aspirin thromboprophylaxis adds independent value to IMPEDE-VTE score for venous thrombosis prediction in multiple myeloma.

Multiple myeloma (MM) is associated to an increased incidence of venous thromboembolism (VTE). IMPEDE-VTE score constitutes a valuable risk assessment tool for VTE prediction in first-line MM patients. Nevertheless, refinement of the primary thromboprophylaxis category of this score (which pools aspirin and heparin) seems desirable. To investigate the role of the type of thromboprophylaxis, within IMPEDE-VTE score, for VTE prediction in MM patients. Retrospective analysis of a single-center cohort of 438 MM patients receiving first-line antimyeloma treatment (1991-2020). IMPEDE-VTE score was calculated. Primary thromboprophylaxis was additionally stratified into aspirin- and heparin-based regimen subgroups. VTE risk was analyzed by Cox regression. Median follow-up during first-line antimyeloma treatment was 6.0 months (IQR 4.1-9.0 months). Twenty-three patients developed VTE (5.3%, 95%CI 3.4-7.8%). IMPEDE-VTE score showed a notable predictive value (area under the ROC curve: 0.70, 95%CI 0.60-0.80). Cox analysis confirmed that 1-point increase in the score resulted in a 1.3-fold increase in VTE risk (HR 1.30, 95%CI 1.13-1.53, p < 0.001). In the multivariable analysis, the type of primary thromboprophylaxis (heparin versus aspirin) was an independent predictive factor (HR 0.15, 95% CI 0.05-0.47, p = 0.001). The combined model showed a higher goodness-of-fit (Akaike Information Criterion [AIC]: 99) than IMPEDE-VTE separately (AIC:235). Our analysis contributes to the external validation of IMPEDE-VTE score for the prediction of VTE in MM. But more interestingly, our results demonstrate that among those patients receiving thromboprophylaxis, the type of regimen (heparin versus aspirin) adds independent predictive value and should be explored for a more accurate risk assessment.

Assessment of the bioavailability of an antibiotic prophylactic protocol in patients undergoing third molar surgery.

The aim of this prospective study was to determine the antibiotic bioavailability of a prophylactic protocol in patients undergoing third molar surgery. Samples from 25 patients were analysed (average age 21 ± 3.89 years, range 18-33 years; 14 female). The patients received single-dose prophylaxis of 2 g amoxicillin orally 1 hour prior to third molar surgery. Venous blood (1.5 ml) and blood from the third molar socket (1.50 ml) were obtained. The amoxicillin plasma concentration was determined in both samples by high performance liquid chromatography with a diode-array detector (HPLC/DAD). Their associations with demographic variables (age, height, weight, body mass index (BMI), sex) and antibiotic exposure time were analyzed using linear regression models. The mean amoxicillin plasma level detected in the venous blood was 1.21 ± 1.17 µg/ml (range 0.49-6.34 µg/ml) and in the third molar socket was 4.14 ± 2.24 µg/ml (range 0.86-7.46 µg/ml) (P < 0.001). No relationship was observed between the bioavailability of the drug and the patient biometric indices evaluated. The prophylactic administration of 2 g amoxicillin in third molar surgery showed greater bioavailability in the molar socket than the concentrations established as necessary to inhibit the growth of microorganisms that cause oral infections. The results show the need to review the current infection control protocols in oral surgery in light of the overestimated doses observed.

An increased percentage of myeloid CD34+ bone marrow cells stratifies intermediate IPSS-R myelodysplastic syndrome patients into prognostically significant groups.

INTRODUCTION: The Revised International Prognostic Scoring System (IPSS-R) for myelodysplastic syndromes (MDS) has established an intermediate category where a disease-modifying intervention is a matter of debate. Flow cytometry allows us to determine a fraction of immature myeloid cells in a semiautomated procedure. The aim of this study, mirroring IPSS-R study inclusion criteria, was to test whether bone marrow (BM) CD34+My percentage has independent prognostic value in the MDS setting. METHODS: BM CD34+My cells were quantified, at diagnosis, selecting CD34+/CD45+/CD11b±/CD13+. Patients were excluded when receiving treatment for altering the natural course of the disease and when IPSS-R could not be calculated due to the lack of metaphases. Finally, Cox analyses were performed, on a series of 260 patients, for overall survival (OS) and time to acute myeloid leukemia (AML) transformation. RESULTS: By analyzing ROC curves, the most accurate prognostic variable, regarding blasts by cytology and CD34+ by cytometry, was the percentage of blasts by microscopy. The percentage of CD34+My in BM showed an AUC of 0.767 and 0.576 for time to AML transformation and OS, respectively. When performing a multivariate regression including the IPSS-R and the percentage of BM CD34+My cells >1%, both factors predicted for a shorter time to AML transformation. In addition, CD34+My percentage successfully stratified the intermediate IPSS-R category into two prognostic groups with a relative risk of 5.73 (95% CI [1.2-27.8]; P = .03). CONCLUSION: We found that BM CD34+My percentage has an independent value concerning the IPSS-R, especially relevant for the prediction of transformation to AML and within the intermediate group.

Genome-wide gene expression changes associated with exposure of rat liver, heart, and kidney cells to endosulfan.

Endosulfan was once the most commonly used pesticide in agriculture and horticulture. It is an environmentally persistent organochlorine compound with the potential to bioaccumulate as it progresses through the food chain. Its acute and chronic toxicity to mammals, including humans, is well known, but the molecular mechanisms of its toxicity are not fully understood. To gain insight to these mechanisms, we examined genome-wide gene expression changes of rat liver, heart, and kidney cells induced by endosulfan exposure. We found that among the cell types examined, kidney and liver cells were the most sensitive and most resilient, respectively, to endosulfan insult. We acquired RNA sequencing information from cells exposed to endosulfan to identify differentially expressed genes, which we further examined to determine the cellular pathways that were affected. In kidney cells, exposure to endosulfan was uniquely associated with altered expression levels of genes constituting the hypoxia-inducible factor-1 (HIF-1) signaling pathway. In heart and liver cells, exposure to endosulfan altered the expression levels of genes for many members of the extracellular matrix (ECM)-receptor interaction pathway. Because both HIF-1 signaling and ECM-receptor interaction pathways directly or indirectly control cell growth, differentiation, proliferation, and apoptosis, our findings suggest that dysregulation of these pathways is responsible for endosulfan-induced cell death.

Systems toxicology of chemically induced liver and kidney injuries: histopathology-associated gene co-expression modules.

Organ injuries caused by environmental chemical exposures or use of pharmaceutical drugs pose a serious health risk that may be difficult to assess because of a lack of non-invasive diagnostic tests. Mapping chemical injuries to organ-specific histopathology outcomes via biomarkers will provide a foundation for designing precise and robust diagnostic tests. We identified co-expressed genes (modules) specific to injury endpoints using the Open Toxicogenomics Project-Genomics Assisted Toxicity Evaluation System (TG-GATEs) - a toxicogenomics database containing organ-specific gene expression data matched to dose- and time-dependent chemical exposures and adverse histopathology assessments in Sprague-Dawley rats. We proposed a protocol for selecting gene modules associated with chemical-induced injuries that classify 11 liver and eight kidney histopathology endpoints based on dose-dependent activation of the identified modules. We showed that the activation of the modules for a particular chemical exposure condition, i.e., chemical-time-dose combination, correlated with the severity of histopathological damage in a dose-dependent manner. Furthermore, the modules could distinguish different types of injuries caused by chemical exposures as well as determine whether the injury module activation was specific to the tissue of origin (liver and kidney). The generated modules provide a link between toxic chemical exposures, different molecular initiating events among underlying molecular pathways and resultant organ damage. Published 2016. This article is a U.S. Government work and is in the public domain in the USA. Journal of Applied Toxicology published by John Wiley & Sons, Ltd.

Prognostic signature and clonality pattern of recurrently mutated genes in inactive chronic lymphocytic leukemia.

An increasing numbers of patients are being diagnosed with asymptomatic early-stage chronic lymphocytic leukemia (CLL), with no treatment indication at baseline. We applied a high-throughput deep-targeted analysis, especially designed for covering widely TP53 and ATM genes, in 180 patients with inactive disease at diagnosis, to test the independent prognostic value of CLL somatic recurrent mutations. We found that 40/180 patients harbored at least one acquired variant with ATM (n=17, 9.4%), NOTCH1 (n=14, 7.7%), TP53 (n=14, 7.7%) and SF3B1 (n=10, 5.5%) as most prevalent mutated genes. Harboring one 'sub-Sanger' TP53 mutation granted an independent 3.5-fold increase of probability of needing treatment. Those patients with a double-hit ATM lesion (mutation+11q deletion) had the shorter median time to first treatment (17 months). We found that a genomic variable: TP53 mutations, most of them under the sensitivity of conventional techniques; a cell phenotypic factor: CD38-positive expression; and a classical marker as ß2-microglobulin, remained as the unique independent predictors of outcome. The high-throughput determination of TP53 status, particularly in this set of patients frequently lacking high-risk chromosomal aberrations, emerges as a key step, not only for prediction modeling, but also for exploring mutation-specific therapeutic approaches and minimal residual disease monitoring.

Neuroprotective mechanisms activated in non-seizing rats exposed to sarin.

Exposure to organophosphate (OP) nerve agents, such as sarin, may lead to uncontrolled seizures and irreversible brain injury and neuropathology. In rat studies, a median lethal dose of sarin leads to approximately half of the animals developing seizures. Whereas previous studies analyzed transcriptomic effects associated with seizing sarin-exposed rats, our study focused on the cohort of sarin-exposed rats that did not develop seizures. We analyzed the genomic changes occurring in sarin-exposed, non-seizing rats and compared differentially expressed genes and pathway activation to those of seizing rats. At the earliest time point (0.25 h) and in multiple sarin-sensitive brain regions, defense response genes were commonly expressed in both groups of animals as compared to the control groups. All sarin-exposed animals activated the MAPK signaling pathway, but only the seizing rats activated the apoptotic-associated JNK and p38 MAPK signaling sub-pathway. A unique phenotype of the non-seizing rats was the altered expression levels of genes that generally suppress inflammation or apoptosis. Importantly, the early transcriptional response for inflammation- and apoptosis-related genes in the thalamus showed opposite trends, with significantly down-regulated genes being up-regulated, and vice versa, between the seizing and non-seizing rats. These observations lend support to the hypothesis that regulation of anti-inflammatory genes might be part of an active and sufficient response in the non-seizing group to protect against the onset of seizures. As such, stimulating or activating these responses via pretreatment strategies could boost resilience against nerve agent exposures.

The relationship of TP53 R72P polymorphism to disease outcome and TP53 mutation in myelodysplastic syndromes.

Nonsynonymous TP53 exon 4 single-nucleotide polymorphism (SNP), R72P, is linked to cancer and mutagen susceptibility. R72P associations with specific cancer risk, particularly hematological malignancies, have been conflicting. Myelodysplastic syndrome (MDS) with chromosome 5q deletion is characterized by erythroid hypoplasia arising from lineage-specific p53 accumulation resulting from ribosomal insufficiency. We hypothesized that apoptotically diminished R72P C-allele may influence predisposition to del(5q) MDS. Bone marrow and blood DNA was sequenced from 705 MDS cases (333 del(5q), 372 non-del(5q)) and 157 controls. Genotype distribution did not significantly differ between del(5q) cases (12.6% CC, 38.1% CG, 49.2% GG), non-del(5q) cases (9.7% CC, 44.6% CG, 45.7% GG) and controls (7.6% CC, 37.6% CG, 54.8% GG) (P=0.13). Allele frequency did not differ between non-del(5q) and del(5q) cases (P=0.91) but trended towards increased C-allele frequency comparing non-del(5q) (P=0.08) and del(5q) (P=0.10) cases with controls. Median lenalidomide response duration increased proportionate to C-allele dosage in del(5q) patients (2.2 (CC), 1.3 (CG) and 0.89 years (GG)). Furthermore, C-allele homozygosity in del(5q) was associated with prolonged overall and progression-free survival and non-terminal interstitial deletions that excluded 5q34, whereas G-allele homozygozity was associated with inferior outcome and terminal deletions involving 5q34 (P=0.05). These findings comprise the largest MDS R72P SNP analysis.

Adenine nucleotide translocase is acetylated in vivo in human muscle: Modeling predicts a decreased ADP affinity and altered control of oxidative phosphorylation.

Proteomics techniques have revealed that lysine acetylation is abundant in mitochondrial proteins. This study was undertaken (1) to determine the relationship between mitochondrial protein acetylation and insulin sensitivity in human skeletal muscle, identifying key acetylated proteins, and (2) to use molecular modeling techniques to understand the functional consequences of acetylation of adenine nucleotide translocase 1 (ANT1), which we found to be abundantly acetylated. Eight lean and eight obese nondiabetic subjects had euglycemic clamps and muscle biopsies for isolation of mitochondrial proteins and proteomics analysis. A number of acetylated mitochondrial proteins were identified in muscle biopsies. Overall, acetylation of mitochondrial proteins was correlated with insulin action (r = 0.60; P < 0.05). Of the acetylated proteins, ANT1, which catalyzes ADP-ATP exchange across the inner mitochondrial membrane, was acetylated at lysines 10, 23, and 92. The extent of acetylation of lysine 23 decreased following exercise, depending on insulin sensitivity. Molecular dynamics modeling and ensemble docking simulations predicted the ADP binding site of ANT1 to be a pocket of positively charged residues, including lysine 23. Calculated ADP-ANT1 binding affinities were physiologically relevant and predicted substantial reductions in affinity upon acetylation of lysine 23. Insertion of these derived binding affinities as parameters into a complete mathematical description of ANT1 kinetics predicted marked reductions in adenine nucleotide flux resulting from acetylation of lysine 23. Therefore, acetylation of ANT1 could have dramatic physiological effects on ADP-ATP exchange. Dysregulation of acetylation of mitochondrial proteins such as ANT1 therefore could be related to changes in mitochondrial function that are associated with insulin resistance.

Novel somatic mutations in large granular lymphocytic leukemia affecting the STAT-pathway and T-cell activation.

T-cell large granular lymphocytic (T-LGL) leukemia is a clonal disease characterized by the expansion of mature CD3+CD8+ cytotoxic T cells. It is often associated with autoimmune disorders and immune-mediated cytopenias. Our recent findings suggest that up to 40% of T-LGL patients harbor mutations in the STAT3 gene, whereas STAT5 mutations are present in 2% of patients. In order to identify putative disease-causing genetic alterations in the remaining T-LGL patients, we performed exome sequencing from three STAT mutation-negative patients and validated the findings in 113 large granular lymphocytic (LGL) leukemia patients. On average, 11 CD8+ LGL leukemia cell-specific high-confidence nonsynonymous somatic mutations were discovered in each patient. Interestingly, all patients had at least one mutation that affects either directly the STAT3-pathway (such as PTPRT) or T-cell activation (BCL11B, SLIT2 and NRP1). In all three patients, the STAT3 pathway was activated when studied by RNA expression or pSTAT3 analysis. Screening of the remaining 113 LGL leukemia patients did not reveal additional patients with same mutations. These novel mutations are potentially biologically relevant and represent rare genetic triggers for T-LGL leukemia, and are associated with similar disease phenotype as observed in patients with mutations in the STAT3 gene.

Evolución de la función renal en la cirugía del aneurisma de aorta abdominal con clampaje suprarrenal / Evolution of renal function in abdominal aortic aneurysm surgery with suprarenal cross-clamping

Objetivo: Analizar los efectos del clampaje suprarrenal (CSR) frente al clampaje infrarrenal (CIR) en la evolución de la función renal en la cirugía del aneurisma de aorta abdominal (AAA). Material y método: Estudio de cohortes retrospectivo de los AAA tratados mediante cirugía abierta electiva entre 1998 y 2011. Se analizó la creatinina sérica (mg/dl) preoperatoria y a las 24, 48, 72, 96 h postoperatorias y al alta. Se definió deterioro de la función renal como una creatinina > 2 mg/dl en los pacientes con una creatinina basal normal o un aumento del doble de la creatinina basal en los pacientes con IRC previa. Se definió deterioro del filtrado glomerular (FG) como una disminución > 25%. Análisis multivariable de la evolución de la función renal. Resultados: Se analizaron 464 AAA, 359 (77,4%) con CIR y 105 (22,6%) con CSR. La prevalencia de IRC preoperatoria fue similar entre ambos grupos. El tipo de clampaje no se asoció a deterioro de la función renal (CSR = 8,6% vs. CIR = 4,7%; p = 0,13) y sí al deterioro del FG (CSR = 27,6% vs. CIR = 13,4%; p = 0,001). El tiempo de clampaje, la pérdida sanguínea y la IRC preoperatoria fueron factores de riesgo independientes para deterioro de la función renal. El tipo de clampaje aumentó el riesgo de deterioro de la función renal a partir de los 30 min (p = 0,001), asociándose a deterioro del FG (OR 2,04; IC 95% 0,94-4,47) de forma independiente. Conclusión: Con CSR inferiores a 30 min, en pacientes con creatinina normal, no es previsible un deterioro de la función renal. Con IRC previa o si se espera un CSR prolongado, es esperable un deterioro de la función renal, por lo que deberían valorarse métodos de protección renal (AU)

Objective: To analyse the effects of suprarenal cross-clamping (SC) as opposed to the infrarenal position (IC) in the evolution of the renal function abdominal aorta aneurysm (AAA) surgery. Material and method: A retrospective cohort study of AAAs treated by elective open surgery between 1998 and 2011. The preoperative level of serum creatinine (mg/dL) was determined and compared to postoperative level at 24, 48, 72 and 96 hours, and on discharge. A deterioration in the renal function was defined as a creatinine > 2 mg/dL in patients with a normal baseline creatinine level or an increase of double the baseline creatinine in patients with a previous chronic renal insufficiency (CRI). A deterioration of the glomerular filtrate (GF) was defined as a > 25% decrease. Multivariable analysis was performed on the evolution of the renal function. Results: A total of 464 AAA’s were analysed, 359 (77.4%) with IC, and 105 (22.6%) with SC. The prevalence of preoperative CRI was similar in both groups. The type of clamp was not associated with a deterioration in the renal function (SC = 8.6% vs. IC = 5.7%; p = 0.13) but was associated with a deterioration of the GF (SC = 27.6% vs. IC = 13.4%; p = 0.001). The time the clamp was in place, the blood loss, and the preoperative CRI were independent risk factors for the deterioration of the renal function. The type of clamp increased the risk of deterioration of the renal function beyond 30 minutes (p = .001), being independently associated with a deterioration in the GF (OR 2.04; 95% CI: 0.94-4.47). Conclusion: With SC less than 30 min, in patients with a creatinine level, a deterioration in the renal function is not foreseeable. With prior CRI, or if a prolonged SC is foreseen, a deterioration in the renal function can be expected, thereby making it necessary to evaluate methods for renal protection (AU)

Pseudoaneurisma postraumático tardío de aorta torácica / Delayed pseudoaneurysm after thoracic aortic injury

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Resultados de la reparación quirúrgica de los aneurismas inflamatorios de aorta abdominal: evolución de los reactantes de fase aguda y de la reacción inflamatoria periaórtica / Results of the surgery of inflammatory abdominal aortic aneurysms: evolution of the acute phase reactants and the periaortic inflammatory reaction

Objetivos: Presentar los resultados del tratamiento quirúrgico electivo de los aneurismas inflamatorios de aorta abdominal (AIAA) y analizar la evolución de la inflamación periaórtica (IPA) y de los reactantes de fase aguda (RFA) tras la intervención. Material y método: Se ha realizado un análisis retrospectivo de los AIAA intervenidos de forma electiva entre 1990 y 2010 mediante cirugía abierta. El seguimiento mediano ha sido de 71 meses y se ha analizado la evolución de la IPA y de los RFA tras la intervención. Resultados: Se han tratado 38 pacientes, de los cuales 12 (31,5%) eran sintomáticos. Se evidenció hidronefrosis en 7 casos (18,4%), siendo necesaria la colocación de doble-J preoperatorio en 5 (13,1%). Un paciente (2,6%) falleció en el postoperatorio inmediato y se realizaron 3 reintervenciones por sangrado (7,8%). Durante el seguimiento la hidronefrosis mejoró en 5 pacientes (71%), siendo la supervivencia a los 12, 36 y 72 meses del 92, 85 y 81% respectivamente. En cuanto a los RFA, se produjo una reducción significativa tanto de la velocidad de sedimentación globular (VSG) (p 0,01), como de la proteína C reactiva (PCR) (p 0,01) tras la cirugía. De igual forma, se redujo de forma significativa la IPA durante el seguimiento, fundamentalmente a partir de los 9 meses tras la intervención (p 0,02). Conclusiones: La cirugía electiva del AIAA ofrece unos buenos resultados a corto y largo plazo, asociándose a una disminución de los RFA y de la IPA, esta última fundamentalmente a partir del noveno mes postoperatorio(AU)

Objectives: To show the results of selective surgical treatment of inflammatory abdominal aortic aneurysms (IAAA), and to analyse the evolution of periaortic inflammation (PAI) and acute phase reactants (APR) after surgery. Patients and method: A retrospective analysis was made of the IAAA electively operated on between 1990 and 2010 by means of open surgery. The median follow-up period was 71 months and an analysis was made of the PAI and APR after surgery. Results: A total 38 patients underwent treatment, of which 12 (31.5%) were symptomatic. Hydronephrosis was evident in 7 cases (18.4%). The implantation of a pre-operative double-J catheter was necessary in 5 cases (13.1%). One patient (2.6%) died in the immediate post-operative period, and 3 were re-operated on due to bleeding (7.8%). During the follow-up period the hydronephrosis improved in 5 patients (71%), with a survival rate at 12, 36 and 72 months of 92%, 85% and 81%, respectively. With regard to the APR, a significant reduction was produced both in the erythrocyte sedimentation rate (ESR) (P=.01) and in the C-reactive protein (CRP) (P=.01) after surgery. Likewise, the PAI was significantly reduced during the follow-up period, mainly from the ninth month following the surgery (P=.02). Conclusions: Selective surgery of IAAA offers good results in the short and long term, associated with a decrease in the APR and PAI, the latter mainly from the ninth month of the post-operative period(AU)

Predicting the effects of amino acid replacements in peptide hormones on their binding affinities for class B GPCRs and application to the design of secretin receptor antagonists.

Computational prediction of the effects of residue changes on peptide-protein binding affinities, followed by experimental testing of the top predicted binders, is an efficient strategy for the rational structure-based design of peptide inhibitors. In this study we apply this approach to the discovery of competitive antagonists for the secretin receptor, the prototypical member of class B G protein-coupled receptors (GPCRs). Proteins in this family are involved in peptide hormone-stimulated signaling and are implicated in several human diseases, making them potential therapeutic targets. We first validated our computational method by predicting changes in the binding affinities of several peptides to their cognate class B GPCRs due to alanine replacement and compared the results with previously published experimental values. Overall, the results showed a significant correlation between the predicted and experimental ΔΔG values. Next, we identified candidate inhibitors by applying this method to a homology model of the secretin receptor bound to an N-terminal truncated secretin peptide. Predictions were made for single residue replacements to each of the other nineteen naturally occurring amino acids at peptide residues within the segment binding the receptor N-terminal domain. Amino acid replacements predicted to most enhance receptor binding were then experimentally tested by competition-binding assays. We found two residue changes that improved binding affinities by almost one log unit. Furthermore, a peptide combining both of these favorable modifications resulted in an almost two log unit improvement in binding affinity, demonstrating the approximately additive effect of these changes on binding. In order to further investigate possible physical effects of these residue changes on receptor binding affinity, molecular dynamics simulations were performed on representatives of the successful peptide analogues (namely A17I, G25R, and A17I/G25R) in bound and unbound forms. These simulations suggested that a combination of the α-helical propensity of the unbound peptide and specific interactions between the peptide and the receptor extracellular domain contribute to their higher binding affinities.