Effect of perioperative hypothermia on surgical site infection in abdominal surgery: A prospective cohort study.

AIM: To estimate the incidence rates of surgical site infection and identify the independent effect of perioperative hypothermia on the incidence of this type of infection in patients undergoing abdominal surgery. BACKGROUND: Around the world, surgical site infection is a frequent complication in surgical patients, mainly causing increased morbidity and mortality rates and health service costs. DESIGN: A prospective cohort study. METHODS: The 484 patients were recruited from a large private philanthropic hospital in the state of São Paulo, Brazil, from July 2016 to May 2017. Crude and adjusted models were constructed for the hypothermia indicators to assess the effect of this exposure on surgical site infection. RESULTS: The incidence rate of surgical site infection was 20.25% (n = 98). The attributable fraction to exposed to hypothermia was >40%. A greater probability of developing surgical site infection (relative risk = 1.89) was found for patients who experienced body temperatures <36.0°C (from entry time into the operating room until the end of the surgery) for more than five hypothermic episodes or longer than 75 min. CONCLUSION: Perioperative hypothermia was an independent risk factor for surgical site infection. SUMMARY STATEMENT: What is already known about this topic? Around the world, surgical site infection is a complication that leads to damage to the patient and increased costs for the health services. Despite recent advances in surgical techniques, surgical site infection remains one of the most frequent complications in abdominal surgery. Perioperative hypothermia can increase the incidence rates of surgical site infection. There is evidence that perioperative hypothermia is associated with surgical site infection in abdominal surgery, but most studies were conducted in developed countries using retrospective designs. What this paper adds? Perioperative hypothermia was identified as an independent risk factor for surgical site infection in patients undergoing abdominal surgery. The attributable fraction to the exposed indicated that, if the main exposure of interest (perioperative hypothermia) could be prevented during surgical anaesthetic procedures, more than 40% of surgical site infection cases would be avoided. The classification of the American Society of Anaesthesiologists was independently associated with the surgical site infection and presented a dose-response effect among its categories. Spinal anaesthesia served as an independent protective factor for surgical site infection. The implications of this paper: The health service managers need to be aware of potential cost-savings associated with perioperative hypothermia prevention as a measure to reduce the incidence of surgical site infection. During the perioperative period, health professionals need to implement effective measures to maintain patients' normothermia, promoting improved care and surgical patient safety. In this context, the nurse's role is fundamental. Future research projects using a prospective design and developed to address the reality of developing countries can contribute to the strengthening and consistency of the findings with a view to a global understanding of the surgical site infection problem.

On the Effect of Native SiO2 on Si over the SPR-mediated Photocatalytic Activities of Au and Ag Nanoparticles.

In hybrid materials containing plasmonic nanoparticles such as Au and Ag, charge-transfer processes from and to Au or Ag can affect both activities and selectivity in plasmonic catalysis. Inspired by the widespread utilization of commercial Si wafers in surface-enhanced Raman spectroscopy (SERS) studies, we investigated herein the effect of the native SiO2 layer on Si wafers over the surface plasmon resonance (SPR)-mediated activities of the Au and Ag nanoparticles (NPs). We prepared SERS-active plasmonic comprised of Au and Ag NPs deposited onto a Si wafer. Here, two kinds of Si wafers were employed: Si with a native oxide surface layer (Si/SiO2 ) and Si without a native oxide surface layer (Si). This led to Si/SiO2 /Au, Si/SiO2 /Ag, Si/Au, and Si/Ag NPs. The SPR-mediated oxidation of p-aminothiophenol (PATP) to p,p'-dimercaptoazobenzene (DMAB) was employed as a model transformation. By comparing the performances and band structures for the Si/Au and Si/Ag relative to Si/SiO2 /Au and Si/SiO2 /Ag NPs, it was found that the presence of a SiO2 layer was crucial to enable higher SPR-mediated PATP to DMAB conversions. The SiO2 layer acts to prevent the charge transfer of SPR-excited hot electrons from Au or Ag nanoparticles to the Si substrate. This enabled SPR-excited hot electrons to be transferred to adsorbed O2 molecules, which then participate in the selective oxidation of PATP to DMAB. In the absence of a SiO2 layer, SPR-excited hot electrons are preferentially transferred to Si instead of adsorbed O2 molecules, leading to much lower PATP oxidation.

Linear lupus erythematosus profundus as an initial manifestation of systemic lupus erythematosus in a child.

The case of a 13-year-old Caucasian girl with a 1-year history of a linear plaque on her thigh is reported. Histopathologic examination of the incisional biopsy tissue established the diagnosis of lupus erythematosus panniculitis. Six months later she developed the clinical and laboratory criteria for the diagnosis of systemic lupus erythematosus (SLE). She was treated with azathioprine and oral prednisolone, with a favorable clinical outcome. Our case illustrates a child with linear lupus erythematosus profundus as an initial manifestation of SLE. To our knowledge, only eight other cases of linear lupus erythematosus profundus have been reported in the literature, five in children. In contrast to our patient, none of those cases progressed to SLE during the reported follow-up period. The authors report this case to illustrate an unusual superimposed segmental manifestation of an inflammatory polygenic disorder.

Mitro-aortic aneurysms in children: single-centre experience and review of the literature.

OBJECTIVES: This publication aims to report the cases of four children with pseudoaneurysm of the mitral-aortic intervalvular fibrosa and carry out a review of the literature. BACKGROUND: Pseudoaneurysm of the mitral-aortic intervalvular fibrosa is a very rare anomaly in children. It can be either congenital or acquired, namely, after bacterial endocarditis or cardiac trauma. This pathology does not usually cause specific symptoms but its outcome may be potentially fatal. METHODS: We report the cases of four patients presenting with pseudoaneurysm of the mitral-aortic intervalvular fibrosa, referred for treatment in a paediatric cardiology clinic. Patient clinical notes were retrospectively reviewed for aetiology, clinical presentation, diagnostic work-up, surgical treatment, and follow-up. Literature on the subject was extensively reviewed. RESULTS: In three patients, pseudoaneurysm of the mitral-aortic intervalvular fibrosa was acquired, being secondary to bacterial endocarditis in two cases and establishing after mitral surgery in another case. The remaining patient had a "congenital" aetiology - no other cause could be traced. The diagnosis was achieved by transthoracic echocardiography for all patients, and confirmed in all by trans-oesophageal echocardiography, to better define morphological details and to access flow into the aneurysmal formation. All patients were submitted to corrective cardiac surgery. Of the patients, three survived and were cured by surgery, staying asymptomatic, and one died after repeated interventions, for persistent endocarditis. CONCLUSIONS: Pseudoaneurysm of the mitral-aortic intervalvular fibrosa is a rare but potentially fatal anomaly. In our experience, surgical cure was achieved for the majority of the cases, except for a case for which infection could not be locally eradicated, leading to multiple reinterventions.

Lung matrix metalloproteinase activation following partial hepatic ischemia/reperfusion injury in rats.

PURPOSE: Warm hepatic ischemia-reperfusion (I/R) injury can lead to multiorgan dysfunction. The aim of the present study was to investigate whether acute liver I/R does affect the function and/or structure of remote organs such as lung, kidney, and heart via modulation of extracellular matrix remodelling. METHODS: Male Sprague-Dawley rats were subjected to 30 min partial hepatic ischemia by clamping the hepatic artery and the portal vein. After a 60 min reperfusion, liver, lung, kidney, and heart biopsies and blood samples were collected. Serum hepatic enzymes, creatinine, urea, Troponin I and TNF-alpha, and tissue matrix metalloproteinases (MMP-2, MMP-9), myeloperoxidase (MPO), malondialdehyde (MDA), and morphology were monitored. RESULTS: Serum levels of hepatic enzymes and TNF-alpha were concomitantly increased during hepatic I/R. An increase in hepatic MMP-2 and MMP-9 activities was substantiated by tissue morphology alterations. Notably, acute hepatic I/R affect the lung inasmuch as MMP-9 activity and MPO levels were increased. No difference in MMPs and MPO was observed in kidney and heart. CONCLUSIONS: Although the underlying mechanism needs further investigation, this is the first study in which the MMP activation in a distant organ is reported; this event is probably TNF-alpha-mediated and the lung appears as the first remote organ to be involved in hepatic I/R injury.

Inhibition of Microbicidal Activity of Canine Macrophages DH82 Cell Line by Capsular Polysaccharides from Cryptococcus neoformans.

Cryptococcus neoformans is a lethal fungus that primarily affects the respiratory system and the central nervous system. One of the main virulence factors is the capsule, constituted by the polysaccharides glucuronoxylomannan (GXM) and glucuronoxylomanogalactan (GXMGal). Polysaccharides are immunomodulators. One of the target cell populations for modulation are macrophages, which are part of the first line of defense and important for innate and adaptive immunity. It has been reported that macrophages can be modulated to act as a "Trojan horse," taking phagocytosed yeasts to strategic sites or having their machinery activation compromised. The scarcity of information on canine cryptococcosis led us to assess whether the purified capsular polysaccharides from C. neoformans would be able to modulate the microbicidal action of macrophages. In the present study, we observed that the capsular polysaccharides, GXM, GXMGal, or capsule total did not induce apoptosis in the DH82 macrophage cell line. However, it was possible to demonstrate that the phagocytic activity was decreased after treatment with polysaccharides. In addition, recovered yeasts from macrophages treated with polysaccharides after phagocytosis could be cultured, showing that their viability was not altered. The polysaccharides led to a reduction in ROS production and the mRNA expression of IL-12 and IL-6. We observed that GXMGal inhibits MHC class II expression and GXM reduces ERK phosphorylation. In contrast, GXMGal and GXM were able to increase the PPAR-γ expression. Furthermore, our data suggest that capsular polysaccharides can reduce the microbicidal activity of canine macrophages DH82.

AMPK involvement in endoplasmic reticulum stress and autophagy modulation after fatty liver graft preservation: a role for melatonin and trimetazidine cocktail.

Ischemia/reperfusion injury (IRI) associated with liver transplantation plays an important role in the induction of graft injury. Prolonged cold storage remains a risk factor for liver graft outcome, especially when steatosis is present. Steatotic livers exhibit exacerbated endoplasmic reticulum (ER) stress that occurs in response to cold IRI. In addition, a defective liver autophagy correlates well with liver damage. Here, we evaluated the combined effect of melatonin and trimetazidine as additives to IGL-1 solution in the modulation of ER stress and autophagy in steatotic liver grafts through activation of AMPK. Steatotic livers were preserved for 24 hr (4°C) in UW or IGL-1 solutions with or without MEL + TMZ and subjected to 2-hr reperfusion (37°C). We assessed hepatic injury (ALT and AST) and function (bile production). We evaluated ER stress (GRP78, PERK, and CHOP) and autophagy (beclin-1, ATG7, LC3B, and P62). Steatotic livers preserved in IGL-1 + MEL + TMZ showed lower injury and better function as compared to those preserved in IGL-1 alone. IGL-1 + MEL + TMZ induced a significant decrease in GRP78, pPERK, and CHOP activation after reperfusion. This was consistent with a major activation of autophagic parameters (beclin-1, ATG7, and LC3B) and AMPK phosphorylation. The inhibition of AMPK induced an increase in ER stress and a significant reduction in autophagy. These data confirm the close relationship between AMPK activation and ER stress and autophagy after cold IRI. The addition of melatonin and TMZ to IGL-1 solution improved steatotic liver graft preservation through AMPK activation, which reduces ER stress and increases autophagy.

Long-term evaluation of endothelial function in Kawasaki disease patients.

BACKGROUND: Kawasaki disease is an acute systemic vasculitis. Cardiac complications are frequent and include endothelial dysfunction in patients with coronary anomalies. So far, the presence of endothelial dysfunction in patients with no coronary lesions has not been demonstrated. Peripheral arterial tonometry (Endo-PAT) measures the microvascular function in response to local ischaemia and has been validated in adult population, but its use in children is scarce. Aim To evaluate endothelial dysfunction in children as a long-term complication after Kawasaki disease using Endo-PAT. METHODS: We evaluated two groups of subjects: (1) Kawasaki disease patients over 11 years of age, diagnosed for >5 years, with no coronary lesions, or any other risk factors for cardiovascular disease; (2) control group of individuals without cardiovascular risk factors. Patients and controls were clinically accessed. Endo-PAT was performed to determine reactive hyperaemia index and augmentation index. RESULTS: A total of 35 individuals (21 males, age 21 ± 6 years) were evaluated (group 1: 19; controls: 16). Kawasaki disease patients presented significant lower reactive hyperaemia index (1.68 ± 0.49 versus 2.31 ± 0.53; p = 0.001). Augmentation index was similar in both groups (-10 ± 7 versus -11 ± 5; p > 0.005). Most patients with Kawasaki disease disclosed endothelial dysfunction (68%) compared with only 12% in controls. CONCLUSIONS: Endo-PAT is feasible and reproducible in the child population. Endothelial dysfunction is a frequent long-term complication in patients after Kawasaki disease with normal appearing coronary arteries. However, these results need validation in a larger population.

Emergent biomarkers of residual cardiovascular risk in patients with low HDL-c and/or high triglycerides and average LDL-c concentrations: focus on HDL subpopulations, Oxidized LDL, adiponectin, and uric acid.

This study intended to determine the impact of HDL-c and/or TGs levels on patients with average LDL-c concentration, focusing on lipidic, oxidative, inflammatory, and angiogenic profiles. Patients with cardiovascular risk factors (n = 169) were divided into 4 subgroups, combining normal and low HDL-c with normal and high TGs patients. The following data was analyzed: BP, BMI, waist circumference and serum glucose, Total-c, TGs, LDL-c, oxidized-LDL, total HDL-c and HDL subpopulations, paraoxonase-1 (PON1) activity, hsCRP, uric acid, TNF- α , adiponectin, VEGF, and iCAM1. The two populations with increased TGs levels, regardless of the normal or low HDL-c, presented obesity and higher waist circumference, Total-c, LDL-c, Ox-LDL, and uric acid. Adiponectin concentration was significantly lower and VEGF was higher in the population with cumulative low values of HDL-c and high values of TGs, while HDL quality was reduced in the populations with impaired values of HDL-c and/or TGs, viewed by reduced large and increased small HDL subfractions. In conclusion, in a population with cardiovascular risk factors, low HDL-c and/or high TGs concentrations seem to be associated with a poor cardiometabolic profile, despite average LDL-c levels. This condition, often called residual risk, is better evidenced by using both traditional and nontraditional CV biomarkers, including large and small HDL subfractions, Ox-LDL, adiponectin, VEGF, and uric acid.

Dax1 modulates ERα-dependent hypothalamic estrogen sensing in female mice.

Coupling the release of pituitary hormones to the developmental stage of the oocyte is essential for female fertility. It requires estrogen to restrain kisspeptin (KISS1)-neuron pulsatility in the arcuate hypothalamic nucleus, while also exerting a surge-like effect on KISS1-neuron activity in the AVPV hypothalamic nucleus. However, a mechanistic basis for this region-specific effect has remained elusive. Our genomic analysis in female mice demonstrate that some processes, such as restraint of KISS1-neuron activity in the arcuate nucleus, may be explained by region-specific estrogen receptor alpha (ERα) DNA binding at gene regulatory regions. Furthermore, we find that the Kiss1-locus is uniquely regulated in these hypothalamic nuclei, and that the nuclear receptor co-repressor NR0B1 (DAX1) restrains its transcription specifically in the arcuate nucleus. These studies provide mechanistic insight into how ERα may control the KISS1-neuron, and Kiss1 gene expression, to couple gonadotropin release to the developmental stage of the oocyte.

Main determinants of PON1 activity in hemodialysis patients.

BACKGROUND/AIMS: Cardiovascular diseases are the major cause of morbidity and mortality in hemodialysis (HD) patients. These patients present reduced paraoxonase 1 (PON1) activity that depends on genetic and non-genetic factors; however, how these factors influence PON1 activity in HD patients is poorly clarified. Our aim was to evaluate the influence of two polymorphisms and non-genetic factors on PON1 activity in HD patients. METHODS: We evaluated 183 HD patients under recombinant human erythropoietin (rhEPO) treatment and 22 healthy individuals. The lipid profile [total cholesterol, triglycerides, HDL-c, LDL-c, apolipoprotein (Apo) A-I, Apo B, lipoprotein(a) and oxidized low-density lipoprotein (Ox-LDL)], inflammatory markers [adiponectin, interleukin-6 (IL-6) and C-reactive protein (CRP)], PON1 activity and PON1 gene polymorphisms (L55M and Q192R) were evaluated. RESULTS: HD patients presented higher levels of IL-6, CRP and Ox-LDL/LDL-c, and lower PON1 activity, total cholesterol, HDL-c, LDL-c, Apo A and Apo B; the most frequent genotype was heterozygosity for L55M polymorphism and homozygosity for the Q allele, the more frequent genotype of Q192R polymorphism. Multiple regression analysis identified heterozygosity and homozygosity for L55M and Q192R polymorphisms, very low-density lipoproteins, LDL-c, Apo A and CRP levels, time on dialysis and rhEPO dose, as the independent variables significantly associated with PON1 activity. The associations with CRP, rhEPO and time on dialysis were negative. CONCLUSION: Our results show that the reduced PON1 activity in HD patients who are not under statin therapy is strongly associated with inflammation, longer time on dialysis and high rhEPO doses, suggesting that the reduction in PON1 activity may worsen the prognosis of these patients.

Lobe-specific heterogeneity and matrix metalloproteinase activation after ischemia/reperfusion injury in rat livers.

Studies assessing the effects of partial-hepatic ischemia/reperfusion (I/R) injury focused on the damage to the ischemic-lobe, whereas few data are available on non-ischemic lobe. This study investigated whether acute liver I/R does affect non-ischemic lobe function via modulation of extracellular matrix remodeling. Male Sprague-Dawley rats underwent left lateral- and median-lobe ischemia for 30 min and reperfusion for 60 min or sham operation. After reperfusion, blood samples and hepatic biopsies from both the ischemic (left-lobe, LL) and the non-ischemic lobe (right-lobe, RL) were collected. Serum hepatic enzymes and TNF-alpha, tissue matrix metalloproteinases (MMP-2, MMP-9), liver morphology, malondialdehyde (MDA), and myeloperoxidase (MPO) were evaluated. Liver I/R injury was confirmed by altered increased hepatic enzymes and TNF-alpha. I/R induced an altered morphology and an increase in MMP-2 and MMP-9 activity not only in left-ischemic lobe (LL) but also in the right-non-ischemic (RL) lobe. A lobar difference was detected for MDA formation and MPO activity in both sham and I/R submitted rats, with higher levels in the left lobe for both groups. This study indicates that an increase in MMPs, which may be TNF-alpha-mediated, occurs in both the ischemic- and the non-ischemic lobes; the heterogeneous lobe concentrations of MDA and MPO suggest that the random sampling of liver tissue should be avoided.

Low level laser effect after micro-marsupialization technique in treating ranulas and mucoceles: a case series report.

The aim of this preliminary study was to investigate the influence of low level laser therapy (LLLT) in alleviating pain caused by micro-marsupialization and the healing of oral ranulas and selected mucoceles. Eleven patients underwent micro-marsupialization treatment associated with LLLT. The patients were irradiated with a 660-nm continuous wave from an indium-gallium-arsenide-phosphorous (InGaAsP) diode laser, at 100 mW, with a spot size on the tissue surface of 0.0283 cm(2) (irradiance = 3.53 W/cm(2)). Irradiation was carried out immediately following micro-marsupialization treatment, as well as at 24, 48, and 72 h post-micro-marsupialization. All treated oral ranulas and selected mucoceles presented clinical healing. No evidence of recurrence could be identified during a mean of 11.0-month follow-up period. The use of InGaAsP diode lasers, within the parameters tested, appears to present a good alternative treatment to reduce pain and heal oral ranulas and selected mucoceles associated with micro-marsupialization.

A Fatal Cause of Rapidly Progressive Heart Failure in a Middle-Aged Woman.

Primary cardiac neoplasms are rare, with 3/4 cases being benign. Most malignant neoplasms are sarcomas. Clinically, they present as pseudovalvular obstruction or remote embolism and rarely as a paraneoplastic syndrome. Median survival depends on complete resection rather than histologic type. We describe the case of a 65-year-old woman who presented to the hospital with a three-month history of asthenia, anorexia, weight loss, and progressive worsening of exertional dyspnea. Transthoracic echocardiogram showed a bulky mass in the auricles with significant transvalvular obstruction of the mitral valve. The CT scan showed a voluminous mass in the interauricular septum with the invasion of both atria and restriction of flow in both pulmonary veins. A transvenous biopsy was performed and histology revealed a primary intimal sarcoma. The patient was not eligible for surgery and was proposed for palliative chemotherapy, but she succumbed to her illness in less than two weeks. This report describes this rare and rapidly fatal disease and reviews the literature.

An Uncommon Presentation of Cryptococcal Meningoencephalitis.

Cryptococcal meningoencephalitis (CM) remains a common cause of central nervous system infections. Patients usually present with headache, fever, malaise, and altered mental status over several weeks. Signs are often absent, but they may include meningism, papilledema, cranial nerve palsies, and depressed level of consciousness. Individuals with CM can occasionally present with small vessel vasculitis causing cerebral lesions. The literature regarding patterns of cerebrovascular injury in CM is scarce. We describe a case of CM in which an unusual presentation was observed: transient focal neurological symptoms initially with absence of fever that led to a misleading primary diagnosis of transient ischemic attack. Since neurological symptoms may be a manifestation of a cryptococcal infection, it is necessary to have a high degree of suspicion for this pathology in the presence of focal neurological deficits, even in patients with vascular risk factors, requiring a thorough etiological investigation.

MnO2-Ir Nanowires: Combining Ultrasmall Nanoparticle Sizes, O-Vacancies, and Low Noble-Metal Loading with Improved Activities towards the Oxygen Reduction Reaction.

Although clean energy generation utilizing the Oxygen Reduction Reaction (ORR) can be considered a promising strategy, this approach remains challenging by the dependence on high loadings of noble metals, mainly Platinum (Pt). Therefore, efforts have been directed to develop new and efficient electrocatalysts that could decrease the Pt content (e.g., by nanotechnology tools or alloying) or replace them completely in these systems. The present investigation shows that high catalytic activity can be reached towards the ORR by employing 1.8 ± 0.7 nm Ir nanoparticles (NPs) deposited onto MnO2 nanowires surface under low Ir loadings (1.2 wt.%). Interestingly, we observed that the MnO2-Ir nanohybrid presented high catalytic activity for the ORR close to commercial Pt/C (20.0 wt.% of Pt), indicating that it could obtain efficient performance using a simple synthetic procedure. The MnO2-Ir electrocatalyst also showed improved stability relative to commercial Pt/C, in which only a slight activity loss was observed after 50 reaction cycles. Considering our findings, the superior performance delivered by the MnO2-Ir nanohybrid may be related to (i) the significant concentration of reduced Mn3+ species, leading to increased concentration of oxygen vacancies at its surface; (ii) the presence of strong metal-support interactions (SMSI), in which the electronic effect between MnOx and Ir may enhance the ORR process; and (iii) the unique structure comprised by Ir ultrasmall sizes at the nanowire surface that enable the exposure of high energy surface/facets, high surface-to-volume ratios, and their uniform dispersion.

Naturally-occurring porphyrins in a spontaneous-tumour bearing mouse model.

An increase in naturally-occurring porphyrins has been described in the blood of subjects bearing different kinds of tumours, that has been proposed as an additional parameter for the diagnosis of occult cancer, although at present the reason for the phenomenon is not exactly defined. In this work the increase of porphyrins in plasma of tumour-bearing subjects has been investigated in parallel with their occurrence in other tissues, considering the systemic iron homeostasis subversion taking place in the presence of cancer. The transgenic female MMTV-neu mouse-developing spontaneous mammary adenocarcinoma has been used as an experimental model, in comparison to non-transgenic C1 mouse as a control. The spleen, accomplishing both hemocatheretic and hemopoietic functions in rodents, and the liver have been considered because of their deep engagement in heme metabolism, entailing both the fate of protoporphyrin IX (PpIX) as its ultimate precursor, and iron homeostasis. Investigations have been performed by means of microspectrofluorometric and image analysis of tissue autofluorescence (AF), and histochemical detection of non-heme iron. In tumour-bearing mouse, along with a marked PpIX presence in tumour, a PpIX enhancement in spleen and liver is observed, that is accompanied by a significant increase in plasma. The phenomenon can be related to a systemic alteration of heme metabolism induced by tumour cells to face their survival and proliferation requirements.

Melatonin protects steatotic and nonsteatotic liver grafts against cold ischemia and reperfusion injury.

Chronic organ-donor shortage has required the acceptance of steatotic livers for transplantation purposes despite the higher risk of graft dysfunction or nonfunction associated with the cold ischemia-reperfusion injury. This study evaluated the use of melatonin as an additive to Institute Georges Lopez (IGL-1) solution for protecting nonsteatotic and steatotic liver grafts against cold ischemia-reperfusion injury. In the current investigation, we used an ex vivo isolated perfused rat liver model. Steatotic and nonsteatotic livers were preserved for 24 hr (4°C) in University of Wisconsin or IGL-1 solutions with or without melatonin, as well as in University of Wisconsin solution alone. Thereafter, livers were subjected to 2-hr reperfusion (37°C). We assessed hepatic injury (transaminases) and function [bile production and sulfobromophthalein (BSP) clearance, vascular resistance], as well as other factors potentially implicated in the high vulnerability of steatotic livers against ischemia-reperfusion injury (oxidative stress and related inflammatory mediators including nitric oxide and cytokines). We also evaluated well-known cytoprotective factors as hemeoxygenase 1 (HO-1). Fatty livers preserved in IGL-1 solution enriched with melatonin showed lower transaminase levels and higher bile production and BSP clearance when compared to those obtained for livers maintained in IGL-1 solution alone. A significant diminution of vascular resistance was also observed when melatonin was added to the IGL-1 solution. The melatonin benefits correlated with the generation of nitric oxide (through constitutive e-NOS activation) and the prevention of oxidative stress and inflammatory cytokine release including tumor necrosis factor and adiponectin, respectively. The addition of melatonin to IGL-1 solution improved nonsteatotic and steatotic liver graft preservation, limiting their risk against cold ischemia-reperfusion injury.

Machine perfusion at 20°C reduces preservation damage to livers from non-heart beating donors.

We previously reported that machine perfusion (MP) performed at 20°C enhanced the preservation of steatotic rat livers. Here, we tested whether rat livers retrieved 30 min after cardiac arrest (NHBDs) were better protected by MP at 20°C than with cold storage. We compared the recovery of livers from NHBDs with organs obtained from heart beating donors (HBDs) preserved by cold storage. MP technique: livers were perfused for 6h with UW-G modified at 20°C. Cold storage: livers were perfused in situ and preserved with UW solution at 4°C for 6h. Both MP and cold storage preserved livers were reperfused with Krebs-Heinselet buffer (2h at 37°C). AST and LDH release and mitochondrial glutamate dehydrogenase (GDH) levels were evaluated. Parameters assessed included: bile production and biliary enzymes; tissue ATP; reduced and oxidized glutathione (GSH/GSSG); protein-SH group concentration. Livers preserved by MP at 20°C showed significantly lower hepatic damage at the end of reperfusion compared with cold storage. GDH release was significantly reduced and bile production, ATP levels, GSH/GSSG and protein-SH groups were higher in livers preserved by MP at 20°C than with cold storage. The best preserved morphology and high glycogen content was obtained with livers submitted to MP at 20°C. Liver recovery using MP at 20°C was comparable to recovery with HBDs. MP at 20°C improves cell survival and gives a better-quality of preservation for livers obtained from NHBDs and may provide a new method for the successful utilization of marginal livers.

[Quadricuspid aortic valve--10-year case series and literature review]. / Válvula aórtica quadricúspide--casuística de 10 anos e revisão da literatura.

INTRODUCTION: Quadricuspid aortic valve is a rare malformation, with an estimated incidence of 0.003 to 0.043% of all congenital heart disease. It usually appears as an isolated congenital anomaly, but may also be associated with other malformations, the most common being coronary artery anomalies. Current technology enables noninvasive diagnosis in most cases. This entity's natural history is progression to valve regurgitation, which is rare before adulthood. OBJECTIVE: Case review of quadricuspid aortic valve patients diagnosed in the last 10 years in a tertiary pediatric cardiology center. METHODS: Retrospective chart review of patients diagnosed with quadricuspid aortic valve between January 2000 and December 2009. RESULTS: Over the past 10 years, four cases of quadricuspid aortic valve were diagnosed in children aged between 6 months and 8 years, two male. In three cases, the four leaflets were of similar size, which is the most common finding. Two of the valves functioned normally and two had minimal regurgitation. All patients had associated cardiac malformations (one atrial and two ventricular septal defects, one supravalvular aortic stenosis and one quadricuspid pulmonary valve). One patient was also diagnosed with Williams syndrome. During a median follow-up of 2 years (0-9), all patients remained asymptomatic and none required medical or surgical treatment of the aortic valve. CONCLUSION: Diagnosis of quadricuspid aortic valve is rare, especially in children, since most patients are asymptomatic and have normally functioning valves. In this study, half the patients had minimal aortic regurgitation. Contrary to what is described in the literature, all patients had concomitant cardiac malformations. We provide the first description of this entity's association with Williams syndrome. Clinical follow-up should be maintained in these patients in order to promptly detect the onset or worsening of functional alterations and to enable appropriate therapeutic intervention.