CLEC5A expression can be triggered by spike glycoprotein and may be a potential target for COVID-19 therapy.

The immune response is crucial for coronavirus disease 19 (COVID-19) progression, with the participation of proinflammatory cells and cytokines, inducing lung injury and loss of respiratory function. CLEC5A expression on monocytes can be triggered by viral and bacterial infections, leading to poor outcomes. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is able to induce neutrophil activation by CLEC5A and Toll-like receptor 2, leading to an aggressive inflammatory cascade, but little is known about the molecular interactions between CLEC5A and SARS-CoV-2 proteins. Here, we aimed to explore how CLEC5A expression could be affected by SARS-CoV-2 infection using immunological tools with in vitro, in vivo, and in silico assays. The findings revealed that high levels of CLEC5A expression were found in monocytes from severe COVID-19 patients in comparison with mild COVID-19 and unexposed subjects, but not in vaccinated subjects who developed mild COVID-19. In hamsters, we detected CLEC5A gene expression during 3-15 days of Omicron strain viral challenge. Our results also showed that CLEC5A can interact with SARS-CoV-2, promoting inflammatory cytokine production, probably through an interaction with the receptor-binding domain in the N-acetylglucosamine binding site (NAG-601). The high expression of CLEC5A and high levels of proinflammatory cytokine production were reduced in vitro by a human CLEC5A monoclonal antibody. Finally, CLEC5A was triggered by spike glycoprotein, suggesting its involvement in COVID-19 progression; therapy with a monoclonal antibody could be a good strategy for COVID-19 treatment, but vaccines are still the best option to avoid hospitalization/deaths.

Impact of intraoperative blood salvage and autologous transfusion during liver transplantation for hepatocellular carcinoma.

PURPOSE: Intraoperative blood salvage (IBS) with autologous blood transfusion is controversial in liver transplantation (LT) for hepatocellular carcinoma (HCC). This study evaluated the role of IBS usage in LT for HCC. METHODS: In a retrospective cohort study at a single center from 2002 to 2018, the outcomes of LT surgery for HCC were analyzed. Overall survival and disease-free survival of patients who received IBS were compared with those who did not receive IBS. Cancer recurrence, length of hospital stay, post-transplant complications, and blood loss also were evaluated. The primary aim of this study was to evaluate overall mid-term and long-term survival (4 and 6 years, respectively). RESULTS: Of the total 163 patients who underwent LT for HCC in the study period, 156 had complete demographic and clinical data and were included in the study. IBS was used in 122 and not used in 34 patients. Ninety-five (60.9%) patients were men, and the mean patient age was 58.5 ± 7.6 years. The overall 1-year, 5-year, and 7-year survival in the IBS group was 84.2%, 67.7%, and 56.8% vs. 85.3%, 67.5%, and 67.5% in the non-IBS group (p = 0.77). The 1-year, 5-year, and 7-year disease-free survival in the IBS group was 81.6%, 66.5%, and 55.4% vs. 85.3%, 64.1%, and 64.1% in the non-IBS group (p = 0.74). For patients without complete HCC necrosis (n = 121), the 1-year, 5-year, and 7-year overall survival rates for those who received IBS (n = 95) were 86.2%, 67.7%, and 49.6% vs. 84.6%, 70.0%, and 70.0% for 26 patients without IBS (p = 0.857). For the same patients, the 1-year, 5-year, and 7-year disease-free survival in the IBS group was 84.0%, 66.8%, and 64.0% vs. 88.0%, 72.8%, and 72.8% in the non-IBS group (p = 0.690). CONCLUSION: IBS does not appear to be associated with worse outcomes in patients undergoing LT for HCC, even in the presence of viable HCC in the explant. There seems to be no reason to contraindicate the use of IBS in LT for HCC.

Pre-transplant ALBI Grade 3 Is Associated with Increased Mortality After Liver Transplantation.

BACKGROUND: Although MELD score is a reliable tool for estimating mortality in the waiting list, criteria for preoperative prediction of survival after liver transplantation (LT) are lacking. ALBI score was validated as a prognostic marker for hepatocellular carcinoma patients undergoing transarterial chemoembolization, hepatic resection, and sorafenib treatment but not for LT outcomes yet. This study aimed to evaluate ALBI score as a prognostic factor in LT. METHODS: This is a single-center analysis of patients undergoing LT between October 2001 and June 2017. Primary endpoint was overall post-LT mortality. Secondary endpoint was 90-day mortality. RESULTS: Of all 301 patients included in this study, 185 (61.5%) were males. The median age was 54.1 ± 11.3 years. Univariate and multivariate analysis revealed that ALBI grade 3 (HR 1.836, 95% CI 1.154-2.921, p = 0.010), low serum albumin (HR 0.628, 95% CI 0.441-0.893, p = 0.010), black race (HR 2.431, 95% CI 1.160-5.092, p = 0.019), and elevated body mass index (HR 1.061, 95% CI 1.022-1.102, p = 0.002) all were associated with decreased overall survival following LT. Patients with both ALBI grade 3 (n = 25) and calculated MELD score ≥ 25 had the lowest overall survival (p < 0.001). DISCUSSION: ALBI grade 3 was related to lower post-LT survival and can be utilized as a tool for risk stratification in LT.

Chemokines and mitochondrial products activate neutrophils to amplify organ injury during mouse acute liver failure.

UNLABELLED: Acetaminophen (APAP) is a safe analgesic and antipyretic drug. However, APAP overdose leads to massive hepatocyte death. Cell death during APAP toxicity occurs by oncotic necrosis, in which the release of intracellular contents can elicit a reactive inflammatory response. We have previously demonstrated that an intravascular gradient of chemokines and mitochondria-derived formyl peptides collaborate to guide neutrophils to sites of liver necrosis by CXC chemokine receptor 2 (CXCR2) and formyl peptide receptor 1 (FPR1), respectively. Here, we investigated the role of CXCR2 chemokines and mitochondrial products during APAP-induced liver injury and in liver neutrophil influx and hepatotoxicity. During APAP overdose, neutrophils accumulated into the liver, and blockage of neutrophil infiltration by anti-granulocyte receptor 1 depletion or combined CXCR2-FPR1 antagonism significantly prevented hepatotoxicity. In agreement with our in vivo data, isolated human neutrophils were cytotoxic to HepG2 cells when cocultured, and the mechanism of neutrophil killing was dependent on direct contact with HepG2 cells and the CXCR2-FPR1-signaling pathway. Also, in mice and humans, serum levels of both mitochondrial DNA (mitDNA) and CXCR2 chemokines were higher during acute liver injury, suggesting that necrosis products may reach remote organs through the circulation, leading to a systemic inflammatory response. Accordingly, APAP-treated mice exhibited marked systemic inflammation and lung injury, which was prevented by CXCR2-FPR1 blockage and Toll-like receptor 9 (TLR9) absence (TLR9(-/-) mice). CONCLUSION: Chemokines and mitochondrial products (e.g., formyl peptides and mitDNA) collaborate in neutrophil-mediated injury and systemic inflammation during acute liver failure. Hepatocyte death is amplified by liver neutrophil infiltration, and the release of necrotic products into the circulation may trigger a systemic inflammatory response and remote lung injury.

Altered responsiveness to extracellular ATP enhances acetaminophen hepatotoxicity.

BACKGROUND: Adenosine triphosphate (ATP) is secreted from hepatocytes under physiological conditions and plays an important role in liver biology through the activation of P2 receptors. Conversely, higher extracellular ATP concentrations, as observed during necrosis, trigger inflammatory responses that contribute to the progression of liver injury. Impaired calcium (Ca2+) homeostasis is a hallmark of acetaminophen (APAP)-induced hepatotoxicity, and since ATP induces mobilization of the intracellular Ca2+ stocks, we evaluated if the release of ATP during APAP-induced necrosis could directly contribute to hepatocyte death. RESULTS: APAP overdose resulted in liver necrosis, massive neutrophil infiltration and large non-perfused areas, as well as remote lung inflammation. In the liver, these effects were significantly abrogated after ATP metabolism by apyrase or P2X receptors blockage, but none of the treatments prevented remote lung inflammation, suggesting a confined local contribution of purinergic signaling into liver environment. In vitro, APAP administration to primary mouse hepatocytes and also HepG2 cells caused cell death in a dose-dependent manner. Interestingly, exposure of HepG2 cells to APAP elicited significant release of ATP to the supernatant in levels that were high enough to promote direct cytotoxicity to healthy primary hepatocytes or HepG2 cells. In agreement to our in vivo results, apyrase treatment or blockage of P2 receptors reduced APAP cytotoxicity. Likewise, ATP exposure caused significant higher intracellular Ca2+ signal in APAP-treated primary hepatocytes, which was reproduced in HepG2 cells. Quantitative real time PCR showed that APAP-challenged HepG2 cells expressed higher levels of several purinergic receptors, which may explain the hypersensitivity to extracellular ATP. This phenotype was confirmed in humans analyzing liver biopsies from patients diagnosed with acute hepatic failure. CONCLUSION: We suggest that under pathological conditions, ATP may act not only an immune system activator, but also as a paracrine direct cytotoxic DAMP through the dysregulation of Ca2+ homeostasis.

Infection by Brazilian and Dutch swine hepatitis E virus strains induces haematological changes in Macaca fascicularis.

BACKGROUND: Hepatitis E virus (HEV) has been described as an emerging pathogen in Brazil and seems to be widely disseminated among swine herds. An autochthonous human case of acute hepatitis E was recently reported. To obtain a better understanding of the phenotypic profiles of both human and swine HEV strains, a experimental study was conducted using the animal model, Macaca fascicularis. METHODS: Six cynomolgus monkeys (Macaca fascicularis) were inoculated intravenously with swine HEV genotype 3 that was isolated from naturally and experimentally infected pigs in Brazil and the Netherlands. Two other monkeys were inoculated with HEV genotype 3 that was recovered from Brazilian and Argentinean patients with locally acquired acute and fulminant hepatitis E. The haematological, biochemical, and virological parameters of all animals were monitored for 67 days. RESULTS: Subclinical hepatitis was observed in all monkeys after inoculation with HEV genotype 3 that was recovered from the infected swine and human patients. HEV RNA was detected in the serum and/or faeces of 6 out of the 8 cynomolgus monkeys between 5 and 53 days after inoculation. The mild inflammation of liver tissues and elevations of discrete liver enzymes were observed. Seroconversions to anti-HEV IgM and/or IgG were detected in 7 animals. Reactivities to anti-HEV IgA were also detected in the salivary samples of 3 animals. Interestingly, all of the infected monkeys showed severe lymphopenia and a trend toward monocytosis, which coincided with elevations in alanine aminotransferase and antibody titres. CONCLUSIONS: The ability of HEV to cross the species barrier was confirmed for both the swine (Brazilian and Dutch) and human (Argentinean) strains, thus reinforcing the zoonotic risk of hepatitis E in South America. Cynomolgus monkeys that were infected with HEV genotype 3 developed subclinical hepatitis that was associated with haematological changes. Haematological approaches should be considered in future studies of HEV infection.

Experimental hepatitis A virus (HAV) infection in cynomolgus monkeys (Macaca fascicularis): evidence of active extrahepatic site of HAV replication.

This work studied the replication sites of hepatitis A virus (HAV) in cynomolgus monkeys (Macaca fascicularis) after intravenous inoculation. The cynomolgus monkeys were inoculated with the Brazilian hepatitis A virus strain (HAF-203). Monkeys were euthanized on days 15, 30, 45 and 60 postinoculation (pi). Liver samples, submandibular salivary gland, mesenteric lymph node and tonsils were removed for virological and pathological evaluation. Immunofluorescence analyses on liver and salivary gland sections using confocal laser scanning microscopy revealed the presence of HAV antigen (HAV Ag). The presence of HAV genome was monitored by real-time PCR. The HAV RNA was detected at 7 days postinoculation (dpi), concomitantly in serum, saliva and faeces. The highest HAV viral load was observed in faeces at 15 dpi (10(5) copies/ml), followed by serum viral load of 10(4) copies/ml at 20 dpi and saliva viral load of 10(3 )copies/ml at 7 dpi. The animals showed first histological and biochemical signs of hepatitis at 15 dpi. The HAV antigen (Ag) was present from day 7 until day 60 pi in the liver and salivary glands. The HAV replicative intermediate was also detected in the liver (4.5 x 10(4) copies/mg), salivary glands (1.9 x 10(3) copies/mg), tonsils (4.2 x 10(1) copies/mg) and lymph nodes (3.4 x 10(1) copies/mg). Our data demonstrated that the salivary gland as an extrahepatic site of early HAV replication could create a potential risk of saliva transmitted infection. In addition, the cynomolgus monkey was confirmed as a suitable model to study the pathogenesis of HAV human infection.

Persistence of Parvovirus B19 in liver from transplanted patients with acute liver failure.

Aim: In this study, we investigated the presence of B19V in liver tissues from patients with acute liver failure (ALF) and evaluated the viral activity in infected liver. Methods: Serum and liver samples from 30 patients who underwent liver transplantation for ALF were investigated for B19V infection by real-time PCR, serological tests and examination of B19V mRNA (transcript) expression in the liver. Results: The serum and liver samples from seven patients were B19V DNA positive (103-105 copies/ml). Most of them presented detectable anti-B19V IgG, indicating persistent infection. B19V mRNA was detected in all patients, demonstrating intra-hepatic replication. Conclusion: B19V infection of the liver during the course of non-A-E ALF suggested a role of B19V, which produced the worst outcome in co-infected patients and in patients with cryptogenic ALF, in liver damage.

Low Aedes aegypti Vector Competence for Zika Virus from Viremic Rhesus Macaques.

Despite worldwide efforts to understand the transmission dynamics of Zika virus (ZIKV), scanty evaluation has been made on the vector competence of Aedes aegypti fed directly on viremic human and non-human primates (NHPs). We blood-fed Ae. aegypti from two districts in Rio de Janeiro on six ZIKV infected pregnant rhesus macaques at several time points, half of which were treated with Sofosbuvir (SOF). Mosquitoes were analyzed for vector competence after 3, 7 and 14 days of incubation. Although viremia extended up to eight days post monkey inoculation, only mosquitoes fed on the day of the peak of viremia, recorded on day two, became infected. The influence of SOF treatment could not be assessed because the drug was administered just after mosquito feeding on day two. The global infection, dissemination and transmission rates were quite low (4.09%, 1.91% and 0.54%, respectively); no mosquito was infected when viremia was below 1.26 × 105 RNA copies/mL. In conclusion, Ae. aegypti vector competence for ZIKV from macaques is low, likely to be due to low viral load and the short duration of ZIKV viremia in primates suitable for infecting susceptible mosquitoes. If ZIKV infection in human and macaques behaves similarly, transmission of the Zika virus in nature is most strongly affected by vector density.

Evolution of the innate and adaptive immune response in women with acute Zika virus infection.

Zika virus (ZIKV) is a flavivirus that is closely related to other human pathogens, such as dengue virus (DENV)1. Primary transmission usually involves Aedes aegypti, which has expanded its distribution range considerably2, although rarer infection routes, including mother-to-fetus transmission, sexual contact and blood transfusion, have also been observed3-7. Primary ZIKV infection is usually asymptomatic or mild in adults, with quickly resolved blood viraemia, but ZIKV might persist for months in saliva, urine, semen, breast milk and the central nervous system8-12. During a recent ZIKV outbreak in South America, substantial numbers of neurological complications, such as Guillain-Barré syndrome, were reported13,14 together with cases of microcephaly and associated developmental problems in infants born to women infected with ZIKV during pregnancy15-20, highlighting the clinical importance of this infection. Analyses of the human immune response to ZIKV are lacking21-28, but the recent outbreak has provided an opportunity to assess ZIKV immunity using current immunological methods. Here, we comprehensively assess the acute innate and adaptive immune response to ZIKV infection in ten women who were recruited during early infection and followed through reconvalescence. We define a cascade of events that lead to immunological control of ZIKV, with previous exposure to DENV impacting some, but not all, mediators of antiviral immunity.

Sofosbuvir shows a protective effect against vertical transmission of Zika virus and the associated congenital syndrome in rhesus monkeys.

The outbreaks of Zika virus (ZIKV) infection in Brazil, 2015-2016, were associated with severe congenital malformations. Our translational study aimed to test the efficacy of the antiviral agent sofosbuvir (SOF) against vertical transmission of ZIKV and the associated congenital syndrome (CZS), using a rhesus monkey model. Eight pregnant macaques were successfully infected during the organogenesis phase with a Brazilian ZIKV strain; five of them received SOF from two to fifteen days post-infection. Both groups of dams showed ZIKV-associated clinical signals, detectable ZIKV RNA in several specimens, specific anti-ZIKV IgM and IgG antibodies, and maternal neutralizing antibodies. However, malformations occurred only among non-treated dam offspring. Compared to non-treated animals, all SOF-treated dams had a shorter ZIKV viremia and four of five neonates had undetectable ZIKV RNA in blood and tissue samples. These results support further clinical evaluations aiming for the prevention of CZS.

Liver preservation prior to transplantation: Past, present, and future.

Since Dr. Thomas Starzl performed the first series of successful liver transplants (LTs), important advances have been made in immunosuppression, operative techniques, and postoperative care. In 1988, Belzer's group reported the first successful LT using the University of Wisconsin preservation solution (UW). Since then, UW has replaced EuroCollins solution and allowed prolonged and safer preservation of liver, kidney, and pancreas allografts, thus contributing to the improvement of transplant outcomes. Although UW is still considered the standard of care in the United States and in several countries worldwide, a recent meta-analysis revealed similar LT outcomes among UW, Celsior solution, and the Institut Georges Lopez-1 preservation solution, which were slightly superior to those obtained with histidine-tryptophan-ketoglutarate preservation solution. Dynamic preservation has been recently developed, and liver allografts are preserved mainly through the following methods: hypothermic machine perfusion, normothermic machine perfusion, and subnormothermic machine perfusion. Their use has the potential advantage of improving clinical results in LT involving extended criteria donor allografts. Although associated with increased costs, techniques employing machine perfusion of liver allografts have been considered clinically feasible. This editorial focuses on recent advances and future perspectives in liver allograft preservation.

Intraoperative cell salvage with autologous transfusion in liver transplantation.

Liver transplant (LT) is the primary treatment for patients with end-stage liver disease. About 25000 LTs are performed annually in the world. The potential for intraoperative bleeding is quite variable. However, massive bleeding is common and requires blood transfusion. Allogeneic blood transfusion has an immunosuppressive effect and an impact on recipient survival, in addition to the risk of transmission of viral infections and transfusion errors, among others. Techniques to prevent excessive bleeding or to use autologous blood have been proposed to minimize the negative effects of allogeneic blood transfusion. Intraoperative reinfusion of autologous blood is possible through previous self-donation or blood collected during the operation. However, LT does not normally allow autologous transfusion by prior self-donation. Hence, using autologous blood collected intraoperatively is the most feasible option. The use of intraoperative blood salvage autotransfusion (IBSA) minimizes the perioperative use of allogeneic blood, preventing negative transfusion effects without negatively impacting other clinical outcomes. The use of IBSA in patients with cancer is still a matter of debate due to the theoretical risk of reinfusion of tumor cells. However, studies have demonstrated the safety of IBSA in several surgical procedures, including LT for hepatocellular carcinoma. Considering the literature available to date, we can state that IBSA should be routinely used in LT, both in patients with cancer and in patients with benign diseases.

Evaluation of HBV-Like Circulation in Wild and Farm Animals from Brazil and Uruguay.

The origin of the hepatitis B virus is a subject of wide deliberation among researchers. As a result, increasing academic interest has focused on the spread of the virus in different animal species. However, the sources of viral infection for many of these animals are unknown since transmission may occur from animal to animal, human to human, animal to human, and human to animal. The aim of this study was to evaluate hepadnavirus circulation in wild and farm animals (including animals raised under wild or free conditions) from different sites in Brazil and Uruguay using serological and molecular tools. A total of 487 domestic wild and farm animals were screened for hepatitis B virus (HBV) serological markers and tested via quantitative and qualitative polymerase chain reaction (PCR) to detect viral DNA. We report evidence of HBsAg (surface antigen of HBV) and total anti-HBc (HBV core antigen) markers as well as low-copy hepadnavirus DNA among domestic and wild animals. According to our results, which were confirmed by partial genome sequencing, as the proximity between humans and animals increases, the potential for pathogen dispersal also increases. A wider knowledge and understanding of reverse zoonoses should be sought for an effective One Health response.

Serological and virological survey of hepatitis E virus (HEV) in animal reservoirs from Uruguay reveals elevated prevalences and a very close phylogenetic relationship between swine and human strains.

Hepatitis E virus (HEV) infection is an issue of public health concern in high-income and non-endemic countries. Increasing evidence supports the hypothesis of a zoonotic route as the main mode of infection in this epidemiological setting, since the transmission of genotypes HEV-3 and HEV-4 from reservoirs to humans has been demonstrated. In America, studies have confirmed the circulation of HEV in pig herds but the zoonotic role of wild boars has never been evaluated. Uruguay has a high burden of HEV- associated acute hepatitis, and a close phylogenetic relationship was observed among human HEV-3 strains and European isolates detected in swine. However in this context, swine herds have never been surveyed. Herein is reported a survey of HEV in swine herds, pigs at slaughter-house and free-living wild boar populations. Two-hundred and twenty sera and 150 liver tissue samples from domestic pigs, and 140 sera from wild boars were tested for HEV by ELISA and PCR-based approaches. All tested swine farms resulted seropositive with an overall rate of 46.8%. In turn, 22.1% of the wild boars had anti-HEV antibodies. HEV RNA was detected in 16.6% and 9.3% of liver samples from slaughter-age pigs and adult wild boars sera, respectively. Three strains from domestic pig were also amplified by nested-PCR approaches. By contrast, none of the positive samples obtained from wild boars could be confirmed by nested-PCR. Phylogenetic analysis revealed a very high nucleotide identity among swine strains and sequences obtained from humans in Uruguay. Results showed that HEV is widely distributed among swine herds in Uruguay. Additionally, this study evidences for the first time in the American continent that wild boar populations are a reservoir for HEV, though its zoonotic role remains to be elucidated. Altogether, data presented here suggest a high zoonotic risk of HEV transmission from swine to humans.

HEPATOCELLULAR CARCINOMA: DIAGNOSIS AND OPERATIVE MANAGEMENT.

INTRODUCTION: Hepatocellular carcinoma is an aggressive malignant tumor with high lethality. AIM: To review diagnosis and management of hepatocellular carcinoma. METHODS: Literature review using web databases Medline/PubMed. RESULTS: Hepatocellular carcinoma is a common complication of hepatic cirrhosis. Chronic viral hepatitis B and C also constitute as risk factors for its development. In patients with cirrhosis, hepatocelular carcinoma usually rises upon malignant transformation of a dysplastic regenerative nodule. Differential diagnosis with other liver tumors is obtained through computed tomography scan with intravenous contrast. Magnetic resonance may be helpful in some instances. The only potentially curative treatment for hepatocellular carcinoma is tumor resection, which may be performed through partial liver resection or liver transplantation. Only 15% of all hepatocellular carcinomas are amenable to operative treatment. Patients with Child C liver cirrhosis are not amenable to partial liver resections. The only curative treatment for hepatocellular carcinomas in patients with Child C cirrhosis is liver transplantation. In most countries, only patients with hepatocellular carcinoma under Milan Criteria are considered candidates to a liver transplant. CONCLUSION: Hepatocellular carcinoma is potentially curable if discovered in its initial stages. Medical staff should be familiar with strategies for early diagnosis and treatment of hepatocellular carcinoma as a way to decrease mortality associated with this malignant neoplasm.

Effects of RNA interference therapy against herpes simplex virus type 1 encephalitis.

BACKGROUND: Herpetic encephalitis (HSE) is caused mainly by herpes simplex virus type 1 (HSV-1) with an annual incidence of 1-4 cases/million inhabitants. Currently, HSE treatment faces difficulties such as the use of antivirals with elevated toxicity, metabolic side effects and HSV-1 resistance. An alternative to antivirals is the use of small interfering RNA (siRNA) as a viral replication inhibitor. In this work, siRNA targeting the UL-39 region was evaluated for HSE treatment in vivo. METHODS: BALB/c mice were inoculated with HSV-1 and treated with siRNA. The treatment was evaluated through kinetics of HSV-1 replication inhibition, number of siRNA doses administered and treatment with siRNA plus acyclovir. All groups were evaluated for signs of HSE, mortality and HSV-1 replication inhibition. RESULTS: The treated group of the kinetic experiment demonstrated a reduction of HSE signs and an HSV-1 replication inhibition of 43.6-99.9% in the brain and 53-98% in trigeminal ganglia (TG). Animals treated with one or two doses of siRNA had a prolonged survival time, reduced clinical signs of HSE and HSV-1 replication inhibition of 67.7% in brains and 85.7% in TG of animals treated with two doses of siRNA. Also, animals treated with siRNA plus acyclovir demonstrated reduced signs of HSE and mortality, as well as HSV-1 replication inhibition in the brain (83.2%) and TG (74.5%). CONCLUSIONS: These findings demonstrated that siRNA was capable of reducing HSE clinical signs, prolonging survival time and inhibiting HSV-1 replication in mice. Thus, siRNA can be a potential alternative to the standard HSE treatment especially to reduce clinical signs and extend survival time in vivo.

USE OF TRANEXAMIC ACID IN TRAUMA PATIENTS: AN ANALYSIS OF COST-EFFECTIVENESS FOR USE IN BRAZIL.

Introduction: Use of tranexamic acid (TXA) in trauma has been the subject of growing interest by researchers and health professionals. However, there are still several open questions regarding its use. In some aspects medical literature is controversial. The points of disagreement among experts include questions such as: Which patients should receive TXA in trauma? Should treatment be performed in the pre-hospital environment? Is there any need for laboratory parameters before starting TXA treatment? What is the drug safety profile? The main issue on which there is still no basis in literature is: What is the indication for treatment within massive transfusion protocols? Objective: Answer the questions proposed based on critical evaluation of the evidence gathered so far and carry out a study of cost-effectiveness of TXA use in trauma adapted to the Brazilian reality. Methods: A literature review was performed through searching Pubmed.com, Embase and Cab Abstract by headings "tranexamic AND trauma", in all languages, yielding 426 articles. Manuscripts reporting on TXA utilization for elective procedures were excluded, remaining 79 articles. Fifty-five articles were selected, and critically evaluated in order to answer study questions. The evaluation of cost effectiveness was performed using CRASH-2 trial data and Brazilian official population data. Results: TXA is effective and efficient, and should be administered to a wide range of patients, including those with indication evaluated in research protocols and current indication criteria for TXA should be expanded. As for the cost-effectiveness, the TXA proved to be cost-effective with an average cost of R$ 61.35 (currently US$16) per year of life saved. Conclusion: The use of TXA in trauma setting seems to be effective, efficient and cost-effective in the various groups of polytrauma patients. Its use in massive transfusion protocols should be the subject of further investigations.

Introdução: O uso do ácido tranexâmico (TXA) no trauma tem sido alvo de interesse crescente por parte de pesquisadores e profissionais de saúde. No entanto, seus benefícios ainda não foram completamente definidos. Os pontos de divergência entre especialistas incluem questões como: quais pacientes devem receber TXA no trauma? O tratamento deve ser realizado em ambiente pré-hospitalar? Há necessidade de exames laboratoriais para indicar o tratamento? Qual o perfil de segurança da droga? A principal questão para a qual ainda não existe qualquer embasamento na literatura é: qual a indicação do tratamento dentro de protocolos de transfusão maciça? Objetivo: Responder às questões propostas, com base em avaliação crítica da evidência reunida até o momento e realizar estudo de custo-efetividade do uso do TXA no trauma adaptado à realidade brasileira. Métodos: Foi realizada revisão da literatura através de estratégia de busca: PubMed.com, Embase e no Cab Abstract pelos descritores "tranexamic AND trauma", em todos idiomas, resultando em 426 artigos. Foram excluídos aqueles relativos às operações eletivas, restando 79 artigos. Cinquenta e cinco foram selecionados e avaliados criticamente com vistas a responder às questões em estudo. A avaliação de custo-efetividade foi realizada utilizando dados do estudo CRASH-2 e populacionais oficiais brasileiros. Resultados: Através da análise da evidência disponível chegou-se à conclusão de que o ácido tranexâmico é tratamento eficaz e efetivo, devendo ser administrado à ampla gama de pacientes, incluindo todos aqueles com indicação já avaliada nos protocolos de pesquisa publicados e provavelmente devam-se expandir os critérios de indicação. Quanto à avaliação de custo-efetividade, o TXA mostrou-se bastante custo-eficaz com gasto médio de R$ 61,35 por ano de vida salvo. Conclusão: O uso do ácido tranexâmico no trauma parece ser eficaz, efetivo e custo-eficaz nos diversos grupos de pacientes politraumatizados. Seu uso em protocolos de transfusão maciça ainda deve ser objeto de futuras investigações.

Serological and molecular evidence of hepadnavirus infection in swine.

INTRODUCTION AND OBJECTIVE: Recently, investigations in a swine herd identified evidence of the existence of a novel member of the Hepadnavirus family endemic in swine. The aim of this study was to investigate the serological and molecular markers of Hepadnavirus circulation in Brazilian domestic swine and wild boar herds, and to evaluate the identity with HBV and other Hepadnaviruses reported previously. MATERIALS AND METHODS: For the study, 376 swine were screened for hepatitis B virus serological markers. Analyses were performed in serum samples using commercial enzyme-linked immunosorbent assay (ELISA) kits (DiaSorin®) for anti-HBc, HBsAg and anti-HBs. Reactive and undetermined swine serum samples were selected to perform DNA viral extraction (QIAamp DNA Mini Kit, Qiagen®), partial genome amplification and genome sequencing. RESULTS: From 376 swine samples analysed, 28 (7.45%) were reactive to anti-HBc, 3 (0.80%) to HBsAg and 6 (1.6%) to anti-HBs. Besides, more 17 (4.52%) swine samples analyzed were classified in the grey zone of the EIA test to anti-HBc and 2 (0.53%) to HBsAg. From 49 samples molecularly analyzed after serological trial, 4 samples showed a positive result for the qualitative PCR for Hepadnavirus. Phylogenetic reconstruction using partial genome sequencing (360 bp) of 3 samples showed similarity with HBV with 90.8-96.3% of identity. CONCLUSIONS: Serological and molecular data showed evidence of the circulation of a virus similar to hepatitis B virus in swine.

First detection of hepatitis E virus in Central Argentina: environmental and serological survey.

BACKGROUND: The hepatitis E virus (HEV) is an emergent causative agent of acute hepatitis worldwide, transmitted by fecal-oral route. In Argentina it is considered rare, so differential laboratory testing is not routinely performed. Besides, in Argentina's central area epidemiological and molecular characteristics of HEV are still unknown. OBJECTIVES: Provide evidence of local circulation of HEV by molecular detection on environmental samples and by serological survey in healthy adult population of Córdoba city, Argentina. STUDY DESIGN: Environmental surveillance was conducted in river and sewage samples collected between 2007 and 2009-2011. Viral detection was performed by RT-Nested PCR of ORF-1 and ORF-2 partial regions. Anti-HEV IgG was determined by EIA in 433 serum samples collected between 2009 and 2010. RESULTS: HEV was detected in 6.3% of raw sewage samples and in 3.2% of riverine samples. Nucleotide sequencing analyses revealed that all isolates belonged to genotype 3, subtypes a, b and c. The prevalence of IgG anti-HEV was 4.4%. Seroprevalence increased with the age of the individuals (OR: 3.50; 95% CI 1.39-8.87; p=0.0065) and, although the prevalence was higher in low income population, no statistical relation was found between anti-HEV and socioeconomic level. CONCLUSIONS: The environmental findings added to serological results, demonstrate that HEV circulates in central Argentina. Contamination of water with HEV could represent a route of transmission for local populations, which have a high number of susceptible individuals. This fact alerts local health care systems in order to include detection of HEV in the diagnostic algorithm of viral hepatitis.