Angel Celdrán

A Nanoconjugate Apaf-1 Inhibitor Protects Mesothelial Cells from Cytokine-Induced Injury

BACKGROUND Inflammation may lead to tissue injury. We have studied the modulation of inflammatory milieu-induced tissue injury, as exemplified by the mesothelium. Peritoneal dialysis is complicated by peritonitis episodes that cause loss of mesothelium. Proinflammatory cytokines are increased in the peritoneal cavity during peritonitis episodes. However there is scarce information on the modulation of cell death by combinations of cytokines and on the therapeutic targets to prevent desmesothelization. METHODOLOGY Human mesothelial cells were cultured from effluents of stable peritoneal dialysis patients and from omentum of non-dialysis patients. Mesothelial cell death was studied in mice with S. aureus peritonitis and in mice injected with tumor necrosis factor alpha and interferon gamma. Tumor necrosis factor alpha and interferon gamma alone do not induce apoptosis in cultured mesothelial cells. By contrast, the cytokine combination increased the rate of apoptosis 2 to 3-fold over control. Cell death was associated with the activation of caspases and a pancaspase inhibitor prevented apoptosis. Specific caspase-8 and caspase-3 inhibitors were similarly effective. Co-incubation with both cytokines also impaired mesothelial wound healing in an in vitro model. However, inhibition of caspases did not improve wound healing and even impaired the long-term recovery from injury. By contrast, a polymeric nanoconjugate Apaf-1 inhibitor protected from apoptosis and allowed wound healing and long-term recovery. The Apaf-1 inhibitor also protected mesothelial cells from inflammation-induced injury in vivo in mice. CONCLUSION Cooperation between tumor necrosis factor alpha and interferon gamma contributes to mesothelial injury and impairs the regenerative capacity of the monolayer. Caspase inhibition attenuates mesothelial cell apoptosis but does not facilitate regeneration. A drug targeting Apaf-1 allows protection from apoptosis as well as regeneration in the course of inflammation-induced tissue injury.

Study of recurrences after anterior open tension-free hernioplasty

SummaryThe anterior open tension-free hernioplasty popularized by the Lichtenstein group has gained world-wide acceptance and popularity. As described by the same group, utilization of a small sheet of mesh and failure to overlap the mesh with the pubic tubercle can lead to recurrence of the hernia. However, recurrence through the internal ring has not been reported. We report three recurrences from the internal ring area after open tension-free hernioplasty. The cause is discussed and the importance of making a mesh shutter mechanism at the internal ring in order to prevent indirect recurrence, is emphasized.

Sevoflurane reduces endothelium-dependent vasorelaxation: role of superoxide anion and endothelin.

PurposeThere are several reports suggesting that volatile anesthetics alter vascular endothelial function. We analyzed the effect of sevoflurane, a fluorinated volatile anesthetic, on nitric oxide (NO)-dependent relaxation, evaluating the role of the endotheliumderived vasoconstrictor endothelin-1 (ET-1).MethodsThe experiments were performed in rat isolated aortic segments aerated in the absence and in the presence of sevoflurane (2%).ResultsAcetylcholine-induced relaxation was reduced in aortic segments aerated with sevoflurane. Sevoflurane failed to modify relaxatation in response to an exogenous NO donor, sodium nitroprusside. Superoxide dismutase, a scavenger of Superoxide anion, partially restored the impaired vasorelaxation induced by sevoflurane, an effect that was associated with the release of Superoxide anion. The presence of BQ-123, an antagonist of endothelin ETA-type receptors, normalized the vasorelaxing response to acetylcholine in the presence of sevoflurane. In addition, BQ-123 also reduced the ability of the sevoflurane-incubated vascular wall to release Superoxide anion.ConclusionsOur results suggest that sevoflurane impairs the endothelium-dependent vasorelaxation but that the endotheliumindependent response remains intact. ET-1 and Superoxide anion are involved in the endothelial dysfunction induced by sevoflurane. Further studies are needed to associate the endothelial dysfunction related to sevoflurane shown herein and its reported preconditioning properties on the myocardium.RésuméObjectifCertains articles suggèrent que les anesthésiques volatils modifient la fonction endothéliale vasculaire. Nous avons analysé l’effet du sévoflurane, un anesthésique volatil fluoré, sur la relaxation liée à l’oxyde nitrique (NO) en évaluant le rôle de l’endothéline-1 (ET-1) vasoconstrictrice d’origine endothéliale.MéthodeLes expériences ont été réalisées sur des segments aortiques isolés de rat aérés en l’absence et en présence de sévoflurane à 2 %.RésultatsLa relaxation induite par l’acétylcholine a été réduite dans les segments aérés avec le sévoflurane. Le sévoflurane n’a pas modifié la relaxation en réponse à un donneur de NO exogène, le nitroprussiate de sodium. La superoxyde dismutase, un piégeur de l’anion superoxyde, a partiellement restauré la vasorelaxation modifiée induite par le sévoflurane, un effet qui est associé à la libération de l’anion superoxyde. La présence de BQ-123, un antagoniste des récepteurs de type endothéline ETA, a normalisé la réponse vasorelaxante à l’acétylcholine en présence du sévoflurane. Le BQ-123 a aussi réduit la capacité de la paroi vasculaire mise en incubation dans le sévoflurane à libérer l’anion superoxyde.ConclusionNos résultats laissent croire que le sévoflurane affecte la vasorelaxation d’origine endothéliale mais que la réponse indépendante de l’endothélium demeure intacte. LET-1 et l’anion superoxyde sont impliqués dans le dérèglement endothélial induit par le sévoflurane. D’autres études seront nécessaires pour pouvoir associer le dérèglement endothélial relié au sévoflurane démontré ici et ses propriétés mentionnées de préconditionnement sur le myocarde.

Aspirin Prevents Escherichia coli Lipopolysaccharide– and Staphylococcus aureus–Induced Downregulation of Endothelial Nitric Oxide Synthase Expression in Guinea Pig Pericardial Tissue

The aim was to analyze whether pericardial tissue expresses endothelial NO synthase (eNOS) protein and to determine the presence of cytosolic proteins that bind to eNOS mRNA. The effect of aspirin on the above-mentioned parameters was also analyzed. eNOS protein was expressed in pericardial tissue from male guinea pigs. Escherichia coli lipopolysaccharide (LPS, 10 &mgr;g/mL) and Staphylococcus aureus endotoxin (SA, 10 &mgr;g/mL) reduced eNOS protein expression and shortened the half-life of the eNOS messenger. Under basal conditions, cytosolic extracts from pericardial samples bound to the 3′-untranslated region (3′-UTR) of eNOS mRNA, which was enhanced by LPS and SA. Proteinase K fully prevented the binding of cytosolic pericardial extracts to 3′-UTR of eNOS mRNA, suggesting the involvement of proteins that were further characterized as 60- and 51-kDa proteins. Aspirin (1 to 10 mmol/L) restored eNOS expression in either LPS- and SA-stimulated pericardial samples and reduced the binding activity of the pericardial cytosolic proteins to 3′-UTR of eNOS mRNA. Indomethacin also reduced the downregulation of eNOS by LPS and diminished the binding activity of the cytosolic proteins, although higher doses of indomethacin than of aspirin were needed to improve these parameters. In conclusion, eNOS protein is expressed in guinea pig pericardial tissue. LPS and SA stimulate the binding activity of pericardial cytosolic proteins to 3′-UTR of eNOS mRNA and reduce eNOS protein expression. High doses of aspirin and indomethacin protect eNOS protein expression and reduce the binding activity of the cytosolic proteins to 3′-UTR of eNOS mRNA, suggesting an inverse association between the presence of these cytosolic proteins and eNOS expression.

UNR/CDSE1 expression as prognosis biomarker in resectable pancreatic ductal adenocarcinoma patients: A proof-of-concept

Pancreatic ductal adenocarcinoma is an aggressive form of pancreatic cancer and the fourth leading cause of cancer-related death. When possible, curative approaches are based on surgical resection, though not every patient is a candidate for surgery. There are clinical guidelines for the management of these patients that offer different treatment options depending on the clinical and pathologic characteristics. However, the survival rates seen in this kind of patients are still low. The CDSE1 gene is located upstream of NRAS and encodes an RNA-binding protein termed UNR. The aim of this study was to analyze UNR expression and its correlation with outcome in patients with resectable pancreatic ductal adenocarcinoma (PDAC). For this, samples from resectable PDAC patients who underwent duodenopancreatectomy were used to evaluate UNR protein expression by immunohistochemistry using a tissue microarray. Here, we observed that low UNR expression was significantly associated with shorter progression-free survival after surgery (P = 0.010). Moreover, this prognostic marker remained significant after Cox proportional hazards model (P = 0.036). We further studied the role of CDSE1 expression in patient’s prognosis using data from public repositories (GEO and TGCA), confirming our results. Interestingly, CDSE1 expression correlated with that of genes characteristic of an immunogenic molecular subtype of pancreatic cancer. Based on these findings, UNR may be considered a potential prognostic biomarker for resectable PDAC and may serve to guide subsequent adjuvant treatment decisions.

Identification of Poor-outcome Biliopancreatic Carcinoma Patients With Two-marker Signature Based on ATF6α and p-p38 "STARD Compliant".

AbstractBiliopancreatic cancer is one of the most aggressive solid neoplasms, and incidence is rising worldwide. It is known that ATF6&agr; is one of the transmembrane proteins that acts crucially in endoplasmic reticulum stress response, and knockdown induces apoptosis of pancreatic cells. Apart from this, p-p38 has been previously correlated with better outcome in pancreatic cancer. Interestingly, ATF6&agr; knockdown pancreatic cells showed increased p-p38. The aim of this study was to evaluate the expression of these 2 proteins, p-p38 and ATF6&agr;, and their correlation with the outcome of biliopancreatic adenocarcinoma patients.Samples from patients with biliopancreatic adenocarcinoma that underwent pancreaticoduodenectomy from 2007 to 2013 were used to construct a tissue microarray to evaluate p-p38 and ATF6&agr; proteins by immunohistochemistry.We observed that both markers showed a tendency to impact in the time to recurrence; then a combination of these 2 proteins was analyzed. Combination of ATF6&agr;high and p-p38low was strongly associated with a higher risk of recurrence (hazard ratio 2.918, P = 0.013). This 2-protein model remained significant after multivariate adjustment.We proposed a 2-protein signature based on ATF6&agr;high and p-p38low as a potential biomarker of risk of recurrence in resected biliopancreatic adenocarcinoma patients.

Sonication of Abdominal Drains: Clinical Implications of Quantitative Cultures for the Diagnosis of Surgical Site Infection.

Abstract Background: The use of drains in patients undergoing abdominal surgery has been a subject of debate for several decades. In this paper, the usefulness of quantitative cultures of sonicated abdominal drains for diagnosing surgical site of infection (SSI) and the association between culture results with patient outcome is evaluated. Methods: Forty-five abdominal drainage tubes from 35 patients who underwent abdominal surgery were studied. Samples were sonicated for 5 min, the sonicate was centrifuged, and the sediment was cultured on different media. Total bacterial counts were adjusted to the actual surface of the drainage tubing. Clinical information of the patients was reviewed retrospectively. Results: A relation was observed between SSI and the use of drains for more than 3 d (p = 0.0216). The presence of a suspected pathogen was related to the prevalence of SSI (p = 0.035), complications (p = 0.013), and greater leukocyte count (p = 0.048 Mann Whitney test), as well as to the use of drains fo...BACKGROUND The use of drains in patients undergoing abdominal surgery has been a subject of debate for several decades. In this paper, the usefulness of quantitative cultures of sonicated abdominal drains for diagnosing surgical site of infection (SSI) and the association between culture results with patient outcome is evaluated. METHODS Forty-five abdominal drainage tubes from 35 patients who underwent abdominal surgery were studied. Samples were sonicated for 5 min, the sonicate was centrifuged, and the sediment was cultured on different media. Total bacterial counts were adjusted to the actual surface of the drainage tubing. Clinical information of the patients was reviewed retrospectively. RESULTS A relation was observed between SSI and the use of drains for more than 3 d (p = 0.0216). The presence of a suspected pathogen was related to the prevalence of SSI (p = 0.035), complications (p = 0.013), and greater leukocyte count (p = 0.048 Mann Whitney test), as well as to the use of drains for more than 3 d (p = 0.0386) and to the serous appearance of the exudates at the point of insertion of the drain (p = 0.0399). The sonication procedure showed a sensitivity of 50%, specificity of 84.2%, positive predictive value of 72.72%, and negative predictive value of 66.67% in the diagnosis of SSI. The most commonly isolated group of organisms was coagulase-negative staphylococci, being present in 18 patients (51.43%) who, however, were not associated with SSI. One or two organisms considered as pathogens were detected in 11 patients (31.43%). The more common pathogens detected were Enterobacteriae spp. (nine patients): Enterobacter aerogenes (2), Enterobacter cloacae (1), Escherichia coli (4), Klebsiella pneumoniae (1), Morganella morganii (1); and Pseudomonas aeruginosa (five patients). Candida spp. and Enterococcus spp. were detected in one patient each one. CONCLUSIONS The detection and quantification of organisms not present in skin microbiota after drain sonication is helpful in the diagnosis of SSI and it is associated with a worse outcome in patients. Duration of use of drainage tubes is an independent risk factor for the development of SSI.

Biocompatibility Reduces Inflammation-Induced Apoptosis in Mesothelial Cells Exposed to Peritoneal Dialysis Fluid

Background/Aims: Peritonitis is a major complication that arises out of peritoneal dialysis (PD), leading to death and loss of mesothelium and peritoneal injury, which may impede PD. We studied the combined impact of inflammatory mediators and PD fluids on mesothelial cell death. Methods: Cultured human mesothelial cells. Results: Inflammatory cytokines (TNF-α and interferon-γ) cooperate with bioincompatible PD fluids containing high glucose degradation product (GDP) concentrations to promote mesothelial cell death. Thus, the inflammatory cytokine cocktail induced a higher rate of death in cells cultured in high GDP PD fluid than in low GDP PD fluid or cell culture medium (cell death expressed as % hypodiploid cells: TNF-α and interferon-γ in RPMI: 14.15 ± 1.68, TNF-α and interferon-γ in 4.25% low GDP PD fluid 13.16 ± 3.29, TNF-α and interferon-γ in 4.25% high GDP PD fluid 25.88 ± 2.18%, p < 0.05 vs. the other two groups). BclxL BH4 peptides, Apaf-1 inhibition or caspase inhibition failed to protect from apoptosis induced by the combination of inflammatory cytokines and bioincompatible PD fluids, although they protected from other forms of mesothelial cell apoptosis. Conclusion: Inflammation cooperates with high GDP PD fluids to promote mesothelial cell death, which is resistant to several therapeutic approaches. This information provides a framework for selection of PD fluid during peritonitis.

Sonication of Abdominal Drains

Abstract Background: The use of drains in patients undergoing abdominal surgery has been a subject of debate for several decades. In this paper, the usefulness of quantitative cultures of sonicated abdominal drains for diagnosing surgical site of infection (SSI) and the association between culture results with patient outcome is evaluated. Methods: Forty-five abdominal drainage tubes from 35 patients who underwent abdominal surgery were studied. Samples were sonicated for 5 min, the sonicate was centrifuged, and the sediment was cultured on different media. Total bacterial counts were adjusted to the actual surface of the drainage tubing. Clinical information of the patients was reviewed retrospectively. Results: A relation was observed between SSI and the use of drains for more than 3 d (p = 0.0216). The presence of a suspected pathogen was related to the prevalence of SSI (p = 0.035), complications (p = 0.013), and greater leukocyte count (p = 0.048 Mann Whitney test), as well as to the use of drains fo...BACKGROUND The use of drains in patients undergoing abdominal surgery has been a subject of debate for several decades. In this paper, the usefulness of quantitative cultures of sonicated abdominal drains for diagnosing surgical site of infection (SSI) and the association between culture results with patient outcome is evaluated. METHODS Forty-five abdominal drainage tubes from 35 patients who underwent abdominal surgery were studied. Samples were sonicated for 5 min, the sonicate was centrifuged, and the sediment was cultured on different media. Total bacterial counts were adjusted to the actual surface of the drainage tubing. Clinical information of the patients was reviewed retrospectively. RESULTS A relation was observed between SSI and the use of drains for more than 3 d (p = 0.0216). The presence of a suspected pathogen was related to the prevalence of SSI (p = 0.035), complications (p = 0.013), and greater leukocyte count (p = 0.048 Mann Whitney test), as well as to the use of drains for more than 3 d (p = 0.0386) and to the serous appearance of the exudates at the point of insertion of the drain (p = 0.0399). The sonication procedure showed a sensitivity of 50%, specificity of 84.2%, positive predictive value of 72.72%, and negative predictive value of 66.67% in the diagnosis of SSI. The most commonly isolated group of organisms was coagulase-negative staphylococci, being present in 18 patients (51.43%) who, however, were not associated with SSI. One or two organisms considered as pathogens were detected in 11 patients (31.43%). The more common pathogens detected were Enterobacteriae spp. (nine patients): Enterobacter aerogenes (2), Enterobacter cloacae (1), Escherichia coli (4), Klebsiella pneumoniae (1), Morganella morganii (1); and Pseudomonas aeruginosa (five patients). Candida spp. and Enterococcus spp. were detected in one patient each one. CONCLUSIONS The detection and quantification of organisms not present in skin microbiota after drain sonication is helpful in the diagnosis of SSI and it is associated with a worse outcome in patients. Duration of use of drainage tubes is an independent risk factor for the development of SSI.