Dissecting the molecular interaction between hepatocytes and Plasmodium liver parasites

Dissertation presented to obtain the Ph.D degree in Biology

Structure-function relationships in a glycosyltransferase, a phosphatase and an oxidoreductase

Dissertation presented to obtain the Ph.D degree in Biochemistry

LIVER BIOPSY: IMPORTANCE OF SPECIMEN SIZE IN THE DIAGNOSIS AND STAGING OF CHRONIC VIRAL HEPATITIS

Liver biopsy is the gold standard method for the grading and staging of chronic viral hepatitis, but optimal biopsy specimen size remains controversial. The aim of this study was to evaluate the quality of liver specimen (number of portal tracts) and to evaluate the impact of the number of portal tracts in the staging of chronic hepatitis. Material and Methods: 468 liver biopsies from consecutive patients with hepatitis C virus and hepatitis B virus infection from 2009 to 2010 were evaluated. Results: The length of fragment was less than 10 mm in 43 cases (9.3%), between 10 and 14 mm in 114 (24.3%), and ≥ 15 mm in 311 (64.4%); of these, in 39 (8.3%) cases were ≥ 20 mm. The mean representation of portal tracts was 17.6 ± 2.1 (5-40); in specimens ≥ 15 mm the mean portal tract was 13.5 ± 4.7 and in cases ≤ 15 mm was 11.4 ± 5.0 (p = 0.002). Cases with less than 11 portal tracts were associated with F3, and cases with 11 or more portal tracts with F2 (p = 0.001). Conclusion: this study demonstrated the good quality of liver biopsy and a relationship between the macroscopic size of the fragment and the number of portal tracts.

NADH oxidase activity of rat and human liver xanthine oxidoreductase: potential role in superoxide production

J Biol Inorg Chem (2007) 12:777–787 DOI 10.1007/s00775-007-0229-7

Membrane structural changes support the involvement of mitochondria in the bile salt-induced apoptosis of rat hepatocytes

Clin Sci (Lond). 2002 Nov;103(5):475-85

Mental Health and Quality of Life in Alcoholic Liver Disease Patients After Liver Transplantation: a Prospective Controlled Study

OBJECTIVE: Alcoholic liver disease (ALD) is one of the most important indications for liver transplantation. Discordant conclusions have been found concerning quality of life and mental health after transplantation in this particular group. The aim of this work was to investigate improvements in mental health and quality of life among transplanted patients for ALD. METHODS: We studied 45 consecutive transplant candidates with ALD, attending the outpatient clinics. Among these patients we transplanted 24 with the control candidates remaining in wait for transplantation. RESULTS: There was a significant improvement in all mental health and quality of life dimensions among the transplanted ALD group. We also observed a favorable evolution of coping mechanisms (CM) in this group. CONCLUSION: There is a favorable adjustment of ALD patients after transplantation as shown in CM evolution, which might explain the improved mental health and quality-of-life dimensions.

Psychiatric and Psychosocial Predictors of Medical Outcome After Liver Transplantation: a Prospective, Single-Center Study

OBJECTIVE: Recognizing the potential impact of psychiatric and psychosocial factors on liver transplant patient outcomes is essential to apply special follow-up for more vulnerable patients. The aim of this article was to investigate the psychiatric and psychosocial factors predicted medical outcomes of liver transplanted patients. METHODS: We studied 150 consecutive transplant candidates, attending our outpatient transplantation clinic, including 84 who had been grafted 11 of whom died and 3 retransplanted. RESULTS: We observed that active coping was an important predictor of length of stay after liver transplantation. Neuroticism and social support were important predictors of mortality after liver transplantation. CONCLUSION: It may be useful to identify patients with low scores for active coping and for social support and high scores for neuroticism to design special modes of follow-up to improve their medical outcomes.

When Does Quality of Life Improve After Liver Transplantation? A Longitudinal Prospective Study

OBJECTIVES: We sought to investigate the improvement in quality of life (mental and physical components) at 1 and 6 months after liver transplantation. METHODS: A sample of liver transplant candidates (n = 60), comprising consecutive patients attending outpatient clinics of a liver transplantation central unit (25% of the patients had familial amyloid polyneuropathy [FAP] and the remaining patents had chronic liver diseases), was assessed by means of the Short Form (SF)-36, Portuguese-validated version, a self-rating questionnaire developed by the Medical Outcome Trust, to investigate certain primary aspects of quality of life, at 3 times: before, and at 1 and 6 months after transplantation. RESULTS: We observed a significant improvement in quality of life (both mental and physical components) by 1 month after transplantation. Between the first month and the sixth month after transplantation, there also was an improvement in the quality of life (both mental and physical components), although only the physical components of quality of life was significantly improved. CONCLUSIONS: Our findings suggested that quality of life improved early after liver transplantation (1 month). Between the first and the sixth months, there only was a significant improvement in the physical quality of life.

Hepatic Artery Thrombosis in Live Liver Donor Transplantation: How to Solve - a Case Report

The decrease in the number of cadaveric donors has proved a limiting factor in the number of liver transplants, leading to the death of many patients on the waiting list. The living donor liver transplantation is an option that allows, in selected cases, increase the number of donors. One of the most serious complications in liver transplantation is hepatic artery thrombosis, in the past considered potentially fatal without urgent re-transplantation. A white male patient, 48 years old, diagnosed with hepatocellular carcinoma in chronic liver failure caused by hepatitis B virus, underwent living donor liver transplantation (right lobe). Doppler echocardiography performed in the immediate postoperative period did not identify arterial flow in the right branch, having been confirmed thrombosis of the right hepatic artery in CT angiography. Urgent re-laparotomy was performed, which consisted of thrombectomy and re-anastomosis of the hepatic artery with segmental splenic artery allograft interposition. The patient started anticoagulation and antiplatelet therapy with acetylsalicylic acid. Serial evaluation with Doppler echocardiography showed hepatic artery patency. At present, the patient is asymptomatic. One of the most devastating complications in liver transplantation, and particularly in living liver donor, is thrombosis of the hepatic artery; thus, early diagnosis and treatment is vital. The rapid intervention for revascularization of the graft avoids irreversible ischemia of the bile ducts and hepatic parenchyma, thus avoiding the need for re-transplantation.

Atheroembolic Renal Disease As a Cause of Allograft Primary Non-Function

Atheroembolic renal disease, also referred to as cholesterol crystal embolization, is a rare cause of renal failure, secondary to occlusion of renal arteries, renal arterioles and glomerular capillaries with cholesterol crystals, originating from atheromatous plaques of the aorta and other major arteries. This disease can occur very rarely in kidney allografts in an early or a late clinical form. Renal biopsy seems to be a reliable diagnostic test and cholesterol clefts are the pathognomonic finding. However, the renal biopsy has some limitations as the typical lesion is focal and can be easily missed in a biopsy fragment. The clinical course of these patients varies from complete recovery of the renal function to permanent graft loss. Statins, acetylsalicyclic acid, and corticosteroids have been used to improve the prognosis. We report a case of primary allograft dysfunction caused by an early and massive atheroembolic renal disease. Distinctive histology is presented in several consecutive biopsies. We evaluated all the cases of our Unit and briefly reviewed the literature. Atheroembolic renal disease is a rare cause of allograft primary non -function but may become more prevalent as acceptance of aged donors and recipients for transplantation has become more frequent.

Prophylactic Use of Liposomal Amphotericin B in Preventing Fungal Infections Early After Liver Transplantation: a Retrospective, Single-Center Study

In this study the authors evaluated the efficacy of prophylaxis with liposomal amphotericin B (L-AmB) in the incidence of fungal infections (FI) during the first 3 months after liver transplant (LT). The study was retrospective and accessed a 4-year period from 2008 to 2011. All patients who died in the first 48 hours after LT were excluded. Patients were divided by the risk groups for FI: Group 1, high-risk (at least 1 of the following conditions: urgent LT; serum creatinine >2 mg/dL; early acute kidney injury [AKI] after LT; retransplantation; surgical exploration early post-LT; transfused cellular blood components [>40 U]); and Group 2, low-risk patients. Group 1 patients were further separated into those who received antifungal prophylaxis with L-AmB and those who did not. Prophylaxis with L-AmB consisted of intravenous administration of L-AmB, 100 mg daily for 14 days. Four hundred ninety-two patients underwent LT; 31 died in the first 48 hours after LT. From the remaining 461 patients, 104 presented with high-risk factors for FI (Group 1); of these, 66 patients received antifungal prophylaxis and 38 did not. In this group 8 FI were observed, 5 in patients without antifungal prophylaxis (P = .011). Three more FI were identified in Group 2. By logistic regression analysis, the categorical variable high-risk group was independently related to the occurrence of invasive FI (P = .006). We conclude that prophylaxis with L-AmB after LT was effective in reducing the incidence of FI. No influence on mortality was detected.

Cutaneous Infection by Different Alternaria Species in a Liver Transplant Recipient

Fungal invasive infections are rare in general population but are an emergent cause of infection in the immunocompromized population, especially in the solid organ transplant recipients. Herein the authors report a clinical case of a liver transplanted patient suffering a cutaneous co-existent infection with A. alternata as well as A. infectoria. To our knowledge this is the first case of cutaneous concomitant infection due to those two species reported not only in Portugal but also worldwide. The patient was treated with surgical excision of the lesions and oral itraconazol without relapse.

Gain-of-Function Mutations in IFIH1 Cause a Spectrum of Human Disease Phenotypes Associated with Upregulated Type I Interferon Signaling

The type I interferon system is integral to human antiviral immunity. However, inappropriate stimulation or defective negative regulation of this system can lead to inflammatory disease. We sought to determine the molecular basis of genetically uncharacterized cases of the type I interferonopathy Aicardi-Goutières syndrome, and of other patients with undefined neurological and immunological phenotypes also demonstrating an upregulated type I interferon response. We found that heterozygous mutations in the cytosolic double-stranded RNA receptor gene IFIH1 (MDA5) cause a spectrum of neuro-immunological features consistently associated with an enhanced interferon state. Cellular and biochemical assays indicate that these mutations confer a gain-of-function - so that mutant IFIH1 binds RNA more avidly, leading to increased baseline and ligand-induced interferon signaling. Our results demonstrate that aberrant sensing of nucleic acids can cause immune upregulation.

Clinical Outcomes and Genetic Expression Profile in Human Liver Graft Dysfunction During Ischemia/Reperfusion Injury

Introduction. This study aims to compare the molecular gene expression during ischemia reperfusion injury. Several surgical times were considered: in the beginning of the harvesting (T0), at the end of the cold ischemia period (T1), and after reperfusion (T2) and compared with graft dysfunction after liver transplant (OLT). Methods. We studied 54 patients undergoing OLT. Clinical, laboratory data, and histologic data (Suzuki classification) as well as the Survival Outcomes Following Liver Transplantation (SOFT) score were used and compared with the molecular gene expression of the following genes: Interleukin (IL)-1b, IL-6, tumor necrosis factor-a, perforin, E-selectin (SELE), Fas-ligand, granzyme B, heme oxygenase-1, and nitric oxide synthetase. Results. Fifteen patients presented with graft dysfunction according to SOFT criteria. No relevant data were obtained by comparing the variables graft dysfunction and histologic variables. We observed a statistically significant relation between SELE at T0 (P ¼ .013) and IL-1b at T0 (P ¼ .028) and early graft dysfunction. Conclusions. We conclude that several genetically determined proinflammatory expressions may play a critical role in the development of graft dysfunction after OLT.

Liver Depurative Techniques: A Single Liver Transplantation Center Experience

In a liver transplant (LT) center, treatments with Prometheus were evaluated. The main outcome considered was 1 and 6 months survival. Methods. During the study period, 74 patients underwent treatment with Prometheus; 64 were enrolled,with a mean age of 51 13 years; 47men underwent 212 treatments (mean, 3.02 per patient). The parameters evaluated were age, sex, laboratorial (liver enzymes, ammonia) and clinical (model for end-stage liver disease and Child-Turcotte-Pugh score) data. Results. Death was verified in 23 patients (35.9%) during the hospitalization period, 20 patients (31.3%) were submitted to liver transplantation, and 21 were discharged. LT was performed in 4 patients with acute liver failure (ALF, 23.7%), in 7 patients with acute on chronic liver failure (AoCLF, 43.7%), and in 6 patients with liver disease after LT (30%). Seven patients who underwent LT died (35%). In the multivariate analysis, older age (P ¼ .015), higher international normalized ratio (INR) (P ¼ .019), and acute liver failure (P ¼ .039) were independently associated with an adverse 1-month clinical outcome. On the other hand, older age (P ¼ .011) and acute kidney injury (P ¼ .031) at presentation were both related to worse 6-month outcome. For patients with ALF and AoCLF we did not observe the same differences. Conclusions. In this cohort, older age was the most important parameter defining 1- and 6-month survival, although higher INR and presence of ALF were important for 1-month survival and AKI for 6-month survival. No difference was observed between patients who underwent LT or did not have LT.