Increased expression of phosphodiesterase 4 in activated hepatic stellate cells promotes cytoskeleton remodeling and cell migration.

Activation and transdifferentiation of hepatic stellate cells (HSC) into migratory myofibroblasts is a key process in liver fibrogenesis. Cell migration requires an active remodeling of the cytoskeleton, which is a tightly regulated process coordinated by Rho-specific guanine nucleotide exchange factors (GEFs) and the Rho family of small GTPases. Rho-associated kinase (ROCK) promotes assembly of focal adhesions and actin stress fibers by regulating cytoskeleton organization. GEF exchange protein directly activated by cAMP 1 (EPAC1) has been implicated in modulating TGFß1 and Rho signaling; however, its role in HSC migration has never been examined. The aim of this study was to evaluate the role of cAMP-degrading phosphodiesterase 4 (PDE4) enzymes in regulating EPAC1 signaling, HSC migration, and fibrogenesis. We show that PDE4 protein expression is increased in activated HSCs expressing alpha smooth muscle actin and active myosin light chain (MLC) in fibrotic tissues of human nonalcoholic steatohepatitis cirrhosis livers and mouse livers exposed to carbon tetrachloride. In human livers, TGFß1 levels were highly correlated with PDE4 expression. TGFß1 treatment of LX2 HSCs decreased levels of cAMP and EPAC1 and increased PDE4D expression. PDE4 specific inhibitor, rolipram, and an EPAC-specific agonist decreased TGFß1-mediated cell migration in vitro. In vivo, targeted delivery of rolipram to the liver prevented fibrogenesis and collagen deposition and decreased the expression of several fibrosis-related genes, and HSC activation. Proteomic analysis of mouse liver tissues identified the regulation of actin cytoskeleton by the kinase effectors of Rho GTPases as a major pathway impacted by rolipram. Western blot analyses confirmed that PDE4 inhibition decreased active MLC and endothelin 1 levels, key proteins involved in cytoskeleton remodeling and contractility. The current study, for the first time, demonstrates that PDE4 enzymes are expressed in hepatic myofibroblasts and promote cytoskeleton remodeling and HSC migration. © 2023 The Pathological Society of Great Britain and Ireland.

Phosphodiesterase 4 Inhibition as a Therapeutic Target for Alcoholic Liver Disease: From Bedside to Bench.

Alcoholic liver disease (ALD) is a major cause of liver-related mortality. There is still no US Food and Drug Administration-approved therapy for ALD, and therefore, identifying therapeutic targets is needed. Our previous work demonstrated that ethanol exposure leads to up-regulation of cAMP-degrading phosphodiesterase 4 (PDE4) expression, which compromises normal cAMP signaling in monocytes/macrophages and hepatocytes. This effect of ethanol on cAMP signaling contributes to dysregulated inflammatory response and altered lipid metabolism. It is unknown whether chronic alcohol consumption in humans alters hepatic PDE4 expression and cAMP signaling and whether inadequate cAMP signaling plays a pathogenic role in alcohol-induced liver injury. Our present work shows that expression of the PDE4 subfamily of enzymes is significantly up-regulated and cAMP levels are markedly decreased in hepatic tissues of patients with severe ALD. We also demonstrate the anti-inflammatory efficacy of roflumilast, a clinically available PDE4 inhibitor, on endotoxin-inducible proinflammatory cytokine production ex vivo in whole blood of patients with alcoholic hepatitis. Moreover, we demonstrate that ethanol-mediated changes in hepatic PDE4 and cAMP levels play a causal role in liver injury in in vivo and in vitro models of ALD. This study employs a drug delivery system that specifically delivers the PDE4 inhibitor rolipram to the liver to avoid central nervous system side effects associated with this drug. Our results show that PDE4 inhibition significantly attenuates ethanol-induced hepatic steatosis and injury through multiple mechanisms, including reduced oxidative and endoplasmic reticulum stress both in vivo and in vitro. Conclusion: Increased PDE4 plays a pathogenic role in the development of ALD; hence, directed interventions aimed at inhibiting PDE4 might be an effective treatment for ALD.

Hepatocyte-specific mitogen-activated protein kinase phosphatase 1 in sexual dimorphism and susceptibility to alcohol induced liver injury.

Background: It is well established that females are more susceptible to the toxic effects of alcohol, although the exact mechanisms are still poorly understood. Previous studies noted that alcohol reduces the expression of mitogen-activated protein kinase phosphatase 1 (MKP1), a negative regulator of mitogen-activated protein kinases (MAPK) in the liver. However, the role of hepatocyte- specific MKP1 in the pathogenesis of alcohol-associated liver disease (ALD) remains uncharacterized. This study aimed to evaluate the role of hepatocyte-specific MKP1 in the susceptibility and sexual dimorphism in alcohol-induced liver injury. Methods: C57Bl/6 mice were used in an intragastric ethanol feeding model of alcohol-associated steatohepatitis (ASH). Hepatocyte-specific Mkp1-/- knockout and (Mkp1+/+ "f/f" male and female mice were subjected to the NIAAA chronic plus binge model. Primary mouse hepatocytes were used for in vitro studies. Liver RNA sequencing was performed on an Illumina NextSeq 500. Liver injury was evaluated by plasma alanine transaminase (ALT), hepatic ER stress and inflammation markers. Statistical analysis was carried out using ANOVA and the unpaired Student's t-test. Results: ASH was associated with the severe injury accompanied by increased endoplasmic reticulum (ER) stress and significant downregulation of Dusp1 mRNA expression. In vitro, ethanol treatment resulted in a time-dependent decrease in Dusp1 mRNA and protein expression in primary hepatocytes in both males and females; however, this effect was significantly more pronounced in hepatocytes from females. In vivo, female mice developed more liver injury in a chronic plus binge model which was accompanied by a significant decrease in liver Dusp1 mRNA expression. In comparison, liver Dusp1 was not changed in male mice, while they developed milder injury to alcohol. Mkp1 deletion in hepatocytes led to increased alcohol induced liver injury, ER stress and inflammation in both sexes. Conclusion: Hepatocyte Mkp1 plays a significant role in alcohol induced liver injury. Alcohol downregulates Mkp1 expression in hepatocytes in a sex dependent manner and could play a role in sexual dimorphism in increased female susceptibility to alcohol.

Dietary copper supplementation reverses hypertrophic cardiomyopathy induced by chronic pressure overload in mice.

Sustained pressure overload causes cardiac hypertrophy and the transition to heart failure. We show here that dietary supplementation with physiologically relevant levels of copper (Cu) reverses preestablished hypertrophic cardiomyopathy caused by pressure overload induced by ascending aortic constriction in a mouse model. The reversal occurs in the continued presence of pressure overload. Sustained pressure overload leads to decreases in cardiac Cu and vascular endothelial growth factor (VEGF) levels along with suppression of myocardial angiogenesis. Cu supplementation replenishes cardiac Cu, increases VEGF, and promotes angiogenesis. Systemic administration of anti-VEGF antibody blunts Cu regression of hypertrophic cardiomyopathy. In cultured human cardiomyocytes, Cu chelation blocks insulin-like growth factor (IGF)-1- or Cu-stimulated VEGF expression, which is relieved by addition of excess Cu. Both IGF-1 and Cu activate hypoxia-inducible factor (HIF)-1alpha and HIF-1alpha gene silencing blocks IGF-1- or Cu-stimulated VEGF expression. HIF-1alpha coimmunoprecipitates with a Cu chaperone for superoxide dismutase-1 (CCS), and gene silencing of CCS, but not superoxide dismutase-1, prevents IGF-1- or Cu-induced HIF-1alpha activation and VEGF expression. Therefore, dietary Cu supplementation improves the condition of hypertrophic cardiomyopathy at least in part through CCS-mediated HIF-1alpha activation of VEGF expression and angiogenesis.

Dysregulated Cyclic Nucleotide Metabolism in Alcohol-Associated Steatohepatitis: Implications for Novel Targeted Therapies.

BACKGROUND: Cyclic nucleotides are second messengers, which play significant roles in numerous biological processes. Previous work has shown that cAMP and cGMP signaling regulates various pathways in liver cells, including Kupffer cells, hepatocytes, hepatic stellate cells, and cellular components of hepatic sinusoids. Importantly, it has been shown that cAMP levels and enzymes involved in cAMP homeostasis are affected by alcohol. Although the role of cyclic nucleotide signaling is strongly implicated in several pathological pathways in liver diseases, studies describing the changes in genes regulating cyclic nucleotide metabolism in ALD are lacking. METHODS: Male C57B/6 mice were used in an intragastric model of alcohol-associated steatohepatitis (ASH). Liver injury, inflammation, and fibrogenesis were evaluated by measuring plasma levels of injury markers, liver tissue cytokines, and gene expression analyses. Liver transcriptome analysis was performed to examine the effects of alcohol on regulators of cyclic AMP and GMP levels and signaling. cAMP and cGMP levels were measured in mouse livers as well as in livers from healthy human donors and patients with alcohol-associated hepatitis (AH). RESULTS: Our results show significant changes in several phosphodiesterases (PDEs) with specificity to degrade cAMP (Pde4a, Pde4d, and Pde8a) and cGMP (Pde5a, Pde6d, and Pde9a), as well as dual-specificity PDEs (Pde1a and Pde10a) in ASH mouse livers. Adenylyl cyclases (ACs) 7 and 9, which are responsible for cAMP generation, were also affected by alcohol. Importantly, adenosine receptor 1, which has been implicated in the pathogenesis of liver diseases, was significantly increased by alcohol. Adrenoceptors 1 and 3 (Adrb), which couple with stimulatory G protein to regulate cAMP and cGMP signaling, were significantly decreased. Additionally, beta arrestin 2, which interacts with cAMP-specific PDE4D to desensitize G-protein-coupled receptor to generate cAMP, was significantly increased by alcohol. Notably, we observed that cAMP levels are much higher than cGMP levels in the livers of humans and mice; however, alcohol affected them differently. Specifically, cGMP levels were higher in patients with AH and ASH mice livers compared with controls. As expected, these changes in liver cyclic nucleotide signaling were associated with increased inflammation, steatosis, apoptosis, and fibrogenesis. CONCLUSIONS: These data strongly implicate dysregulated cAMP and cGMP signaling in the pathogenesis of ASH. Future studies to identify changes in these regulators in a cell-specific manner could lead to the development of novel targeted therapies for ASH.

Novel Liposomal Rolipram Formulation for Clinical Application to Reduce Emesis.

Introduction: The phosphodiesterase 4 (PDE4) inhibitor, rolipram, has beneficial effects on tissue inflammation, injury and fibrosis, including in the liver. Since rolipram elicits significant CNS side-effects in humans (ie, nausea and emesis), our group developed a fusogenic lipid vesicle (FLV) drug delivery system that targets the liver to avoid adverse events. We evaluated whether this novel liposomal rolipram formulation reduces emesis. Methods: C57Bl/6J male mice were used to compare the effect of three doses of free and FLV-delivered (FLVs-Rol) rolipram in a behavioral correlate model of rolipram-induced emesis. Tissue rolipram and rolipram metabolite levels were measured using LC-MS/MS. The effect of FLVs-Rol on brain and liver PDE4 activities was evaluated. Results: Low and moderate doses of free rolipram significantly reduced anesthesia duration, while the same doses of FLVs-Rol had no effect. However, the onset and duration of adverse effects (shortening of anesthesia period) elicited by a high dose of rolipram was not ameliorated by FLVs-Rol. Post-mortem analysis of brain and liver tissues demonstrated that FLVs affected the rate of rolipram uptake by liver and brain. Lastly, administration of a moderate dose of FLVs-Rol attenuated endotoxin induced PDE4 activity in the liver with negligible effect on the brain. Discussion: The findings that the low and moderate doses of FLVs-Rol did not shorten the anesthesia duration time suggest that FLV delivery prevented critical levels of drug from crossing the blood-brain barrier (BBB) to elicit CNS side-effects. However, the inability of high dose FLVs-Rol to prevent CNS side-effects indicates that there was sufficient unencapsulated rolipram to cross the BBB and shorten anesthesia duration. Notably, a moderate dose of FLVs-Rol was able to decrease PDE4 activity in the liver without affecting the brain. Taken together, FLVs-Rol has a strong potential for clinical application for the treatment of liver disease without side effects.

Genome Sequences of 22 T1-like Bacteriophages That Infect Enterobacteriales.

Here, the full genome sequences of 22 T1-like bacteriophages isolated from wastewater are reported. Eight (BlueShadow, Brooksby, Devorator, ElisaCorrea, Reinasaurus, SorkZaugg, Supreme284, ZeroToHero) were isolated on Citrobacter, six on Klebsiella (Chell, FairDinkum, HazelMika, Opt-817, P528, PeteCarol), and eight on Escherichia (Fulano1, Mishu, Opt-719, PhleaSolo, Punny, Poky, Phunderstruck, Sadiya).

Nitrotyrosinylation, remodeling and endothelial-myocyte uncoupling in iNOS, cystathionine beta synthase (CBS) knockouts and iNOS/CBS double knockout mice.

Increased levels of homocysteine (Hcy), recognized as hyperhomocysteinemia (HHcy), were associated with cardiovascular diseases. There was controversy regarding the detrimental versus cardio protective role of inducible nitric oxide synthase (iNOS) in ischemic heart disease. The aim of this study was to test the hypothesis that the Hcy generated nitrotyrosine by inducing the endothelial nitric oxide synthase, causing endothelial-myocyte (E-M) coupling. To differentiate the role of iNOS versus constitutive nitric oxide synthase (eNOS and nNOS) in Hcy-mediated nitrotyrosine generation and matrix remodeling in cardiac dysfunction, left ventricular (LV) tissue was analyzed from cystathionine beta synthase (CBS) heterozygote knockout, iNOS homozygote knockout, CBS-/+/iNOS-/- double knockout, and wild-type (WT) mice. The levels of nitrotyrosine, MMP-2 and -9 (zymographic analysis), and fibrosis (by trichrome stain) were measured. The endothelial-myocyte function was determined in cardiac rings. In CBS-/+ mice, homocysteine was elevated and in iNOS-/- mice, nitric oxide was significantly reduced. The nitrotyrosine and matrix metalloproteinase-9 (MMP-9) levels were elevated in double knockout and CBS-/+ as compared to WT mice. Although MMP-2 levels were similar in CBS-/+, iNOS-/-, and CBS-/+/iNOS-/-, the levels were three- to fourfold higher than WT. The levels of collagen were similar in CBS-/+ and iNOS-/-, but they were threefold higher than WT. Interesting, the levels of collagen increased sixfold in double knockouts, compared to WT, suggesting synergism between high Hcy and lack of iNOS. Left ventricular hypertrophy was exaggerated in the iNOS-/- and double knockout, and mildly increased in the CBS-/+, compared to WT mice. The endothelial-dependent relaxation was attenuated to the same extent in the CBS-/+ and iNOS-/-, compared to WT, but it was robustly blunted in double knockouts. The results concluded that homocysteine generated nitrotyrosine in the vicinity of endothelium, caused MMP activation and endothelium-myocyte uncoupling. The generation of nitrotyrosine was independent of iNOS.

Cytochrome P450 (CYP) 2J2 gene transfection attenuates MMP-9 via inhibition of NF-kappabeta in hyperhomocysteinemia.

Hyperhomocysteinemia (HHcy) is associated with atherosclerotic events involving the modulation of arachidonic acid (AA) metabolism and the activation of matrix metalloproteinase-9 (MMP-9). Cytochrome P450 (CYP) epoxygenase-2J2 (CYP2J2) is abundant in the heart endothelium, and its AA metabolites epoxyeicosatrienoic acids (EETs) mitigates inflammation through NF-kappabeta. However, the underlying molecular mechanisms for MMP-9 regulation by CYP2J2 in HHcy remain obscure. We sought to determine the molecular mechanisms by which P450 epoxygenase gene transfection or EETs supplementation attenuate homocysteine (Hcy)-induced MMP-9 activation. CYP2J2 was over-expressed in mouse aortic endothelial cells (MAECs) by transfection with the pcDNA3.1/CYP2J2 vector. The effects of P450 epoxygenase transfection or exogenous supplementation of EETs on NF-kappabeta-mediated MMP-9 regulation were evaluated using Western blot, in-gel gelatin zymography, electromobility shift assay, immunocytochemistry. The result suggested that Hcy downregulated CYP2J2 protein expression and dephosphorylated PI3K-dependent AKT signal. Hcy induced the nuclear translocation of NF-kappabeta via downregulation of IKbetaalpha (endogenous cytoplasmic inhibitor of NF-kappabeta). Hcy induced MMP-9 activation by increasing NF-kappabeta-DNA binding. Moreover, P450 epoxygenase transfection or exogenous addition of 8,9-EET phosphorylated the AKT and attenuated Hcy-induced MMP-9 activation. This occurred, in part, by the inhibition of NF-kappabeta nuclear translocation, NF-kappabeta-DNA binding and activation of IKbetaalpha. The study unequivocally suggested the pivotal role of EETs in the modulation of Hcy/MMP-9 signal.

Role of copper and homocysteine in pressure overload heart failure.

Elevated levels of homocysteine (Hcy) (known as hyperhomocysteinemia HHcy) are involved in dilated cardiomyopathy. Hcy chelates copper and impairs copper-dependent enzymes. Copper deficiency has been linked to cardiovascular disease. We tested the hypothesis that copper supplement regresses left ventricular hypertrophy (LVH), fibrosis and endothelial dysfunction in pressure overload DCM mice hearts. The mice were grouped as sham, sham + Cu, aortic constriction (AC), and AC + Cu. Aortic constriction was performed by transverse aortic constriction. The mice were treated with or without 20 mg/kg copper supplement in the diet for 12 weeks. The cardiac function was assessed by echocardiography and electrocardiography. The matrix remodeling was assessed by measuring matrix metalloproteinase (MMP), tissue inhibitor of metalloproteinases (TIMPs), and lysyl oxidase (LOX) by Western blot analyses. The results suggest that in AC mice, cardiac function was improved with copper supplement. TIMP-1 levels decreased in AC and were normalized in AC + Cu. Although MMP-9, TIMP-3, and LOX activity increased in AC and returned to baseline value in AC + Cu, copper supplement showed no significant effect on TIMP-4 activity after pressure overload. In conclusion, our data suggest that copper supplement helps improve cardiac function in a pressure overload dilated cardiomyopathic heart.

Pedro Belou. Conferencia de 1936 sobre la hipoacusia laboral y el ruido urbano / Pedro Belou. Conference delivered in 1936 on occupational hearing loss and urban noise / Pedro Belou. Conferência de 1936 sobre perda auditiva ocupacional e ruído urbano

La problemática del ruido en las ciudades toma preponderancia internacional a finales del siglo XX, y pocas veces se comentan los esfuerzos pioneros realizados por especialistas que abogaron por un ambiente sonoro saludable. Éste es el caso de Pedro Belou, un médico otorrinolaringólogo nacido en Uruguay quien realizó toda su carrera profesional en Argentina, y que se destacó como científico de renombre mundial. A Belou podríamos ubicarlo como uno de los pioneros en el Río de la Plata en advertir acerca de las enfermedades que genera en las personas la exposición al ruido en las ciudades y en las industrias durante una conferencia que dio en Buenos Aires en 1936. En este artículo se rescatan los contenidos de su ponencia por la actualidad que tienen sus argumentos, y también para contribuir a su biografía, ya que esta conferencia no se menciona en ninguna de sus biografías.

Summary: City noise became a significant issue at the global level towards the end of the 20th Century, and discussions on pioneer efforts conducted by specialists who advocated for a healthy sound environment are rare. This is the case of Pedro Belou, a Uruguayan born otolaryngologist who developed his professional career in Argentina and was a renowned scientist worldwide. Belou could be regarded as one of the first physicians in the River Plate to warn us about diseases arising from noise exposure in cities and factories, during a conference he delivered in Buenos Aires in 1936. This article brings his presentation to you given the current relevance of his argument and to contribute to his biography, since this conference has not been mentioned in any of his previous biographies.

O problema do ruído nas cidades ganha preponderância internacional no final do século XX, porém raramente se discute o pioneirismo de especialistas que defendiam um ambiente sonoro saudável, como é o caso de Pedro Belou; otorrinolaringologista nascido no Uruguai, passou toda a sua carreira profissional na Argentina, destacando-se como um cientista de renome mundial. Poderíamos colocar Belou como um dos pioneiros no Río de la Plata em alertar, em uma conferência que deu em Buenos Aires em 1936, sobre as doenças que afetam as pessoas devido à exposição ao ruído nas cidades e nas indústrias. Neste artigo o conteúdo de sua apresentação é resgatado devido não somente pela atualidade de seus argumentos, como também para contribuir com sua biografia, já que esta conferência não é mencionada em nenhuma delas.

Portomesenteric Vein Thrombosis After Laparoscopic Sleeve Gastrectomy: Incidence, Analysis and Follow-Up in 1236 Consecutive Cases.

BACKGROUND: Portomesenteric vein thrombosis (PMVT) is a rare but severe complication after laparoscopic bariatric surgery, with potentially serious consequences. We aimed to describe the incidence, clinical features, management, outcome, and midterm follow-up in patients with PMVT after laparoscopic sleeve gastrectomy (LSG). METHODS: This retrospective and descriptive study included patients who underwent LSG between November 2009 and July 2015 and developed PMVT. The following data were analyzed: age, gender, body mass index (BMI), thrombosis risk factors, surgical technique, thromboembolic prophylaxis, primary surgery outcomes, clinical features, treatment, thrombophilia testing results, and follow-up findings, including imaging and endoscopic findings. RESULTS: A total of 1236 patients underwent LSG, and 5 (0.4 %) developed PMVT. The mean age was 34.4 years, and 3 patients were women. The mean BMI was 38.5 kg/m2. Two patients had received hormonal contraceptive treatment. Four patients had a history of smoking. All of the patients received anticoagulant treatment, and none required surgery. The mean hospitalization duration was 7.6 days. Two patients showed complete recanalization. One patient showed portal cavernomatosis on delayed images. Two patients had a positive thrombophilia test. No portal hypertension endoscopic findings were observed. CONCLUSIONS: PMVT is a rare complication, for which smoking was identified as a predominant risk factor. Early diagnosis and prompt anticoagulant therapy could lead to a dramatic decrease in the incidence of intestinal infarction, mortality, and extrahepatic portal hypertension in the near future. However, careful follow-up is necessary to evaluate the impact of PMVT on long-term patient outcomes.

Role of matrix metalloproteinase-9 in endothelial apoptosis in chronic heart failure in mice.

Accumulation of oxidized extracellular matrix between endothelium and muscle is an important risk factor in the endothelium-myocytes uncoupling in congestive heart failure. Although ventricular remodeling is accompanied by increased matrix metalloproteinase (MMP)-9 activity, it is unclear whether MMP-9 plays a role in endothelial apoptosis in chronic volume overload congestive heart failure. We tested the hypothesis that, in chronic volume overload, myocardial dysfunction involves endocardial endothelial (EE) apoptosis in response to MMP-9 activation, extracellular matrix accumulation, and endothelium-myocytes uncoupling. Arteriovenous fistula (AVF) was created in control (FVB/NJ) and MMP-9 knockout (MMP-9KO; FVB.Cg-MMP9(tm1Tvu)/J) mice. Sham surgery was used as control. Mice were grouped as follows: wild type, n = 3 (sham control); MMP-9KO, n = 3 (sham); AVF, n = 3; and MMP-9KO + AVF (n = 3). Heart function was analyzed by M-mode and Doppler echocardiography, and with a pressure-tipped Millar catheter placed in the left ventricle of anesthetized mice 8 wk after AVF. Apoptosis was detected by measuring caspase-3, transferase-mediated dUTP nick-end labeling (TUNEL), and CD-31 by immunolabeling. Protease-activated receptors-1, connexin-43, and a disintegrin and MMP-12 (ADAM-12) expression were measured by Western blot analyses. MMP-2 and MMP-9 expression were measured by quantitative RT-PCR. Compared with control, AVF caused an increase in left ventricle end diastolic pressure and decrease in -dP/dt. In contrast, in the MMP-9KO + AVF group, these variables were changed toward control levels. Increased EE apoptosis (caspase-3 activation and TUNEL/CD-31 colabeling) in AVF mice was prevented in the MMP-9KO + AVF group. Protease-activated receptor-1, connexin-43, and ADAM-12 were induced in AVF. MMP-9 gene ablation ameliorated the induction. The results suggest that impaired cardiac function in volume overload is associated with EE apoptosis, cardiac remodeling, and endothelium-myocytes uncoupling in response to MMP-9 activation.

Hyperhomocysteinemic diabetic cardiomyopathy: oxidative stress, remodeling, and endothelial-myocyte uncoupling.

Accumulation of oxidized-matrix (fibrosis) between the endothelium (the endothelial cells embedded among the myocytes) and cardiomyocytes is a hallmark of diabetes mellitus and causes diastolic impairment. In diabetes mellitus, elevated levels of homocysteine activate matrix metalloproteinase and disconnect the endothelium from myocytes. Extracellular matrix functionally links the endothelium to the cardiomyocyte and is important for their synchronization. However, in diabetes mellitus, a disconnection is caused by activated metalloproteinase, with subsequent accumulation of oxidized matrix between the endothelium and myocyte. This contributes to endothelial-myocyte uncoupling and leads to impaired diastolic relaxation of the heart in diabetes mellitus. Elevated levels of homocysteine in diabetes are attributed to impaired homocysteine metabolism by glucose and insulin and decreased renal clearance. Homocysteine induces oxidative stress and is inversely related to the expression of peroxisome proliferators activated receptor (PPAR). Several lines of evidence suggest that ablation of the matrix metalloproteinase (MMP-9) gene ameliorates the endothelial-myocyte uncoupling in diabetes mellitus. Homocysteine competes for, and decreases the PPARgammaactivity. In diabetes mellitus, endothelial-myocyte uncoupling is associated with matrix metalloproteinase activation and decreased PPARgamma activity. The purpose of this review is to discuss the role of endothelial-myocyte uncoupling in diabetes mellitus and increased levels of homocysteine, causing activation of latent metalloproteinases, decreased levels of thioredoxin and peroxiredoxin, and cardiac tissue inhibitor of metalloproteinase (CIMP) in response to antagonizing PPARgamma.

Task and error analysis balancing benefits over business of electronic medical records.

Task and error analysis research was performed to identify: a) the process for healthcare organisations in managing healthcare for patients with mental illness or substance abuse; b) how the process can be enhanced and; c) if electronic medical records (EMRs) have a role in this process from a business and safety perspective. The research question is if EMRs have a role in enhancing the healthcare for patients with mental illness or substance abuse. A discussion on the business of EMRs is addressed to understand the balancing act between the safety and business aspects of an EMR.

Síndrome de cimitarra, valoración con ecocardiografía transesofágica intraoperatoria. Informe de caso / Scimitar syndrome; intraoperative transesophageal echocardiography assessment. Case report

9-year-old patient diagnosed with scimitar syndrome through transthoracic echocardiogram and cardiac catheterization. Surgical correction is performed by anastomosing the collector of the pulmonary right vein to AI through the interatrial septum, tunneling it with a pericardic patch. The study findings and echocardiographic images of such surgical repair and the spectrum of pulsed Doppler differentiating between right and left pulmonary veins will be shown below. The connection through the septum was evidenced, simulating an interatrial communication. A difference was found among the measured points S, D, A and between the left and right pulmonary veins, without this resulting in a stenosis during the repair.

Paciente de 9 años de edad el cual es diagnosticado con síndrome de cimitarra a través de ecografía transtorácica y cateterismo cardiaco. Se realiza cirugía correctora la cual se anastomosa el colector de vena pulmonar derecha hacia AI a través del septum interauricular, tunelizándolo con parche pericárdico. A continuación se muestran los hallazgos e imágenes ecocardiográficas de tal reparación y el espectro doppler pulsado diferenciado entre las venas pulmonares derechas e izquierdas. Se pudo evidenciar la conexión a través del septum, simulando una comunicación interauricular. Se halló una diferencia entre los puntos medidos S, D, A entre las venas pulmonares izquierdas y derechas, sin que esto significara una estenosis en la reparación.

Ecocardiografía intraoperatoria: causa de la hipotensión post circulación extracorporea / Intraoperative echocardiography. cause of the hypotension post circulation extracorporea / Ecocardiografia intraoperatória. causa da hipotensão pós-circulação extracorporea

RESUMEN: En la práctica diaria uno de los eventos que más se presenta es la hipotensión luego de la salida de circulación extracorpórea (CEC). La posibilidad de contar con ecocardiografía a partir del 2015 en el nosocomio ha ayudado a orientar al anestesiólogo sobre el estado hemodinámico, sin embargo, no se ha podido esclarecer la causa de esta hipotensión utilizando esta herramienta. El objetivo de este estudio es hallar los parámetros ecocardiográficos que más se relacionan con la hipotensión refractaria luego de la salida de la (CEC). Se seleccionaron pacientes sometidos a cirugías de comunicación interauricular e interventricular monitorizados con ecocardiografía transesofágica. La muestra se estratificó en dos grupos, hipotensos (casos) y normotensos (controles) luego de la salida de CEC. Estudio observacional, de casos y controles, retrospectivo. En el análisis del total de pacientes se encontraron diferencias estadísticamente significativas (p<0.05) de los parámetros ecocardiográficos indicadores de hipovolemia entre los grupos. No hubo diferencias estadísticas (p=0.083) en los parámetros ecocardiográficos de contractilidad. Los resultados obtenidos demostraron que los parámetros ecográficos de hipovolemia fueron los que más se asociaron al momento de la hipotensión. Esto permite orientar al profesional a un uso racional de drogas inotrópicas y reposición de volumen.

SUMMARY: In daily practice, one of the most frequent events is hypotension after the of extracorporeal circulation (ECC). The possibility of having an echocardiography from 2015 has been a guiding means in the hemodynamic state, however, the cause of this hypotension has not been clarified. The aim of this study is to find the echocardiographic parameters that are most related to refractory hypotension after ECC. Patients undergoing atrial and interventricular communication surgeries monitored with transesophageal echocardiography were selected. The sample was stratified into two groups, hypotensive (cases) and normotensive (controls) after ECC. Observational, case-control study, retrospective. In the analysis of the total of the patients, were found statistically significant differences (p <0.05) in the echocardiographic parameters indicating hypovolemia between the groups. There were no differences in the statistics (p = 0.83) in the echocardiographic parameters of contractility. The results showed that the ultrasonographic parameters of hypovolemia were those associated with hypotension. This allows the professional to be guided to a rational use of inotropic drugs and volume replacement.

RESUMO: Na prática diária, um dos eventos mais frequentes é a hipotensão após a saída da circulação extracorpórea (CEC). A possibilidade de ter ecocardiografia a partir de 2015 no hospital ajudou a orientar o anestesista sobre o estado hemodinâmico, no entanto, não foi capaz de esclarecer a causa desta hipotensão usando esta ferramenta. O objetivo deste estudo é encontrar os parâmetros ecocardiográficos mais relacionados à hipotensão refratária após a saída da artéria coronária (CEC). Pacientes submetidos a cirurgias de comunicação atrial e interventricular monitoradas por ecocardiograma transesofágico foram selecionados. A amostra foi estratificada em dois grupos, hipotensivos (casos) e normotensos (controles) após a saída do CEC. Estudo observacional, caso-controle, retrospectivo. Na análise do número total de pacientes, foram encontradas diferenças estatisticamente significantes (p <0,05) nos parâmetros ecocardiográficos indicativos de hipovolemia entre os grupos. Não houve diferenças estatísticas (p = 0,083) nos parâmetros ecocardiográficos de contratilidade. Os resultados obtidos mostraram que os parâmetros ultrassonográficos da hipovolemia foram os mais associados no momento da hipotensão. Isso permite que o profissional seja orientado para o uso racional de drogas inotrópicas e reposição de volume.

Primeros implantes de la válvula sin sutura Perceval S® en Argentina / First Perceval S™ Sutureless Aortic Valve Prosthesis Implantations in Argentina

RESUMEN El reemplazo valvular aórtico con prótesis sin sutura es una alternativa innovadora para el tratamiento de la estenosis aórtica en los ancianos y en los pacientes de alto riesgo. Aunque la experiencia mundial con estas prótesis lleva ya varios años, solo recientemente comenzó a comercializarse en Argentina el modelo Perceval S®. Se trata de una prótesis autoexpandible sin sutura hecha de pericardio bovino y montada en un stent de nitinol. En este estudio se presentan los primeros tres casos de reemplazo valvular aórtico con la bioprótesis Perceval realizados en Argentina. La técnica sin sutura es una alternativa prometedora para el reemplazo valvular aórtico quirúrgico con una bioprótesis, y, posiblemente, pueda competir con la terapéutica intravascular en los pacientes de alto riesgo.

ABSTRACT Aortic valve replacement with sutureless prostheses is an innovative alternative for the treatment of aortic stenosis in the el-derly and in high-risk patients. Although the world experience with these prostheses has been going on for several years, only recently, the Perceval S™ model, consisting of a self-expanding sutureless prosthesis made of bovine pericardium and mounted on a nitinol stent, has begun to be commercialized in Argentina. In this study, we present the first three cases of aortic valve replacement with Perceval bioprostheses performed in Argentina. The sutureless technique is a promising alternative for surgi-cal aortic valve replacement with a bioprosthesis, and may possibly compete with intravascular therapy in high-risk patients.

Cystathionine beta synthase gene dose dependent vascular remodeling in murine model of hyperhomocysteinemia.

Although children born with severe homocystinurea (i.e. cystathionine beta synthase homozygote knockout, CBS-/-) develop deleterious vascular complications with structural malformation and do not live past teenage, the heterozygote (CBS-/+) lives with apparently normal phenotype. Interestingly, this differential role of CBS expression in vascular remodeling is unclear. Peroxisome proliferator activated receptor gamma (PPARγ) is nuclear transcription factor that mitigates vascular complications. The hypothesis was that homocysteine (Hcy) decreased thioredoxin (Trx), peroxiredoxin (Prx), increased NADPH oxidase (NOX1), mitochondrial nitric oxide synthase (mtNOS) activity and reactive oxygen species (ROS) in mitochondria in a CBS gene dose-dependent manner. ROS transduced matrix metalloproteinase (MMP) activation causing thickening (fibrosis) of the basement membrane, rendering ineffective endothelial nitric oxide synthase (eNOS) and promoted endothelial-smooth muscle disconnection/uncoupling by antagonizing PPARγ. Wild type (WT-CBS+/+), CBS-/+ and CBS -/- mice were treated with or without ciglitazone (CZ, a PPARγ agonist) in food at birth. Aortic nuclear PPARγ expression was measured by EMSA. Aortic mtNOS activity and ROS production was measured using NO- and H(2)O(2)-electrodes, respectively. Aorta was analyzed for Trx, Prx, by Western blot, and PCR. MMP activity was by in situ zymography. Aortic function was measured in tissue myobath. The results suggested 90% morbidity in CBS-/- allele at 12 wks. However, treatment with the PPARγ agonist, CZ significantly reduced the morbidity to 20%. In addition, CZ restored the PPARγ activity in CBS-/+ and -/- mice to normal levels. The oxidative stress was alleviated by CZ treatment. In situ labeling with mito-tracker suggests co-localization of ROS with mitochondrial mitophagy. The mtNOS activity was increased in HHcy compared to WT. The data support the notion that Hcy decreases redoxins, increases mtNOS activity and ROS/oxidase in mitochondrial mitophagy in a gene dose-dependent manner of CBS. ROS transduces MMP activation, rendering ineffective eNOS and promotes endothelial-smooth muscle disconnection/uncoupling by antagonizing PPARγ. We suggest that the children born with severe ho-mocystineurea may do better if treated with PPARγ agonist.

Restoration of contractility in hyperhomocysteinemia by cardiac-specific deletion of NMDA-R1.

Homocysteine (HCY) activated mitochondrial matrix metalloproteinase-9 and led to cardiomyocyte dysfunction, in part, by inducing mitochondrial permeability (MPT). Treatment with MK-801 [N-methyl-d-aspartate (NMDA) receptor antagonist] ameliorated the HCY-induced decrease in myocyte contractility. However, the role of cardiomyocyte NMDA-receptor 1 (R1) activation in hyperhomocysteinemia (HHCY) leading to myocyte dysfunction was not well understood. We tested the hypothesis that the cardiac-specific deletion of NMDA-R1 mitigated the HCY-induced decrease in myocyte contraction, in part, by decreasing nitric oxide (NO). Cardiomyocyte-specific knockout of NMDA-R1 was generated using cre/lox technology. NMDA-R1 expression was detected by Western blot and confocal microscopy. MPT was determined using a spectrophotometer. Myocyte contractility and calcium transients were studied using the IonOptix video-edge detection system and fura 2-AM loading. We observed that HHCY induced NO production by agonizing NMDA-R1. HHCY induced the MPT by agonizing NMDA-R1. HHCY caused a decrease in myocyte contractile performance, maximal rate of contraction and relaxation, and prolonged the time to 90% peak shortening and 90% relaxation by agonizing NMDA-R1. HHCY decreased contraction amplitude with the increase in calcium concentration. The recovery of calcium transient was prolonged in HHCY mouse myocyte by agonizing NMDA-R1. It was suggested that HHCY increased mitochondrial NO levels and induced MPT, leading to the decline in myocyte mechanical function by agonizing NMDA-R1.