Review of genetic and epigenetic alterations in hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is associated with multiple risk factors and is believed to arise from pre-neoplastic lesions, usually in the background of cirrhosis. However, the genetic and epigenetic events of hepatocarcinogenesis are relatively poorly understood. HCC display gross genomic alterations, including chromosomal instability (CIN), CpG island methylation, DNA rearrangements associated with hepatitis B virus (HBV) DNA integration, DNA hypomethylation and, to a lesser degree, microsatellite instability. Various studies have reported CIN at chromosomal regions, 1p, 4q, 5q, 6q, 8p, 10q, 11p, 16p, 16q, 17p and 22q. Frequent promoter hypermethylation and subsequent loss of protein expression has also been demonstrated in HCC at tumor suppressor gene (TSG), p16, p14, p15, SOCS1, RIZ1, E-cadherin and 14-3-3 sigma. An interesting observation emerging from these studies is the presence of a methylator phenotype in hepatocarcinogenesis, although it does not seem advantageous to have high levels of microsatellite instability. Methylation also appears to be an early event, suggesting that this may precede cirrhosis. However, these genes have been studied in isolation and global studies of methylator phenotype are required to assess the significance of epigenetic silencing in hepatocarcinogenesis. Based on previous data there are obvious fundamental differences in the mechanisms of hepatic carcinogenesis, with at least two distinct mechanisms of malignant transformation in the liver, related to CIN and CpG island methylation. The reason for these differences and the relative importance of these mechanisms are not clear but likely relate to the etiopathogenesis of HCC. Defining these broad mechanisms is a necessary prelude to determine the timing of events in malignant transformation of the liver and to investigate the role of known risk factors for HCC.

Bile duct ligation in neonatal rats: Is it a valid experimental model for biliary atresia studies?

BA is the most important disease requiring liver transplantation in children. Common BDL in rats is a classic experimental model to study biliary obstruction. The response of the neonatal animal to BDL has yet to be completely understood and few reports have focused on the behavioral differences of the liver between neonatal and adult animals. Ninety newborn Wistar rats aged six days, weighing 8.0-13.9 g, and 90 adult Wistar rats weighing 199.7-357.0 g, were submitted to BDL. After surgery, they were randomly divided and killed on the 3rd, 5th, 7th, 14th, 21st and 28th day post-BDL. Hepatic biopsies were obtained and the following were measured: (i) semiquantification of the bile ductule proliferation and inflammatory infiltrate by HE stain, (ii) quanti. cation of portal and periportal fibrosis with the Sirius-red stain. Although the initial response of ductule proliferation and inflammatory infiltrate were less intense in the newborn animal, the portal and periportal fibrosis were higher when compared with adult animals (p < 0.0491). These findings may contribute to the understanding of the pathophysiology of BA.

A quantitative coronary angiography-matched comparison between a prospective randomised multicentre cutting balloon angioplasty and bare metal stent trial (REDUCE III) and the Rapamycin-Eluting Stent Evaluation At Rotterdam Cardiology Hospital (RESEARCH) study

Aims: There remains significant concern about the long-term safety of drug-eluting stents (DES). However, bare metal stents (BMS) have been used safely for over two decades. There is therefore a pressing need to explore alternative strategies for reducing restenosis with BMS. This study was designed to examine whether IVUS-guided cutting balloon angioplasty (CBA) with BMS could convey similar restenosis rates to DES. Methods and results: In the randomised REstenosis reDUction by Cutting balloon angioplasty Evaluation (REDUCE III) study, 521 patients were divided into four groups based on device and IVUS use before BMS (IVUS-CBA-BMS: 137 patients; Angio-CBA-BMS: 123; IVUS-BA-BMS: 142; and Angio-BA-BMS: 119). At follow-up, the IVUS-CBA-BMS group had a significantly lower restenosis rate (6.6%) than the other groups (p=0.016). We performed a quantitative coronary angiography (QCA) based matched comparison between an IVUS-guided CBA-BMS strategy (REDUCE III) and a DES strategy (Rapamycin-Eluting-Stent Evaluation At Rotterdam Cardiology. Hospital, the RESEARCH study). We matched the presence of diabetes, vessel size, and lesion severity by QCA. Restenosis (>50% diameter stenosis at follow-up) and target vessel revascularisation (TVR) were examined. QCA-matched comparison resulted in 120-paired lesions. While acute gain was significantly greater in IVUS-CBA-BMS than DES (1.65 +/- 0.41 mm vs. 1.28 +/- 0.57 mm, p=0.001), late loss was significantly less with DES than with IVUS-CBA-BMS (0.03 +/- 0.42 mm vs. 0.80 +/- 0.47 mm, p=0.001). However, no difference was found in restenosis rates (IVUS-CBA-BMS: 6.6% vs. DES: 5.0%, p=0.582) and TVR (6.6% and 6.6%, respectively). Conclusions: An IVUS-guided CBA-BMS strategy yielded restenosis rates similar to those achieved by DES and provided an effective alternative to the use of DES.

Wegener`s granulomatosis: experience from a Brazilian tertiary center

Most epidemiological studies with Wegener`s granulomatosis (WG) patients are based on populations from the Northern hemisphere, whereas very few studies have been conducted in Southern hemisphere populations, particularly from South America. The authors performed a large retrospective, demographic study including clinical and laboratory profiles of 134 consecutive WG patients seen at one Brazilian center from 1999 to 2009. Mean age at initial WG diagnosis was 43.4 +/- 15.5 years, and mean disease duration was 8.6 +/- 6.6 years. Sixty-four (47.8%) patients were male and a total of 113 (84.3%) subjects were white. Ear/nose/throat involvement occurred in 85.8%. The classic lung and renal involvement were observed in 77.6% and 75.4%, respectively, followed by ocular (35.8%), musculoskeletal (33.4%), cutaneous (29.1%), neurological (20.1%), cardiac (11.2%), and genitourinary involvement in 2.2% of cases. Cytoplasmic pattern-antineutrophil cytoplasmic antibody was detected in 83 (61.9%) cases. Ten (7.5%) individuals presented limited forms of WG. Classic therapy with corticosteroids and cyclophosphamide was used in 97 cases (72.4%). There were no cases of tuberculosis or Pneumocystis jiroveci pneumonia, but cutaneous herpes zoster occurred in eight (6.0%) individuals. There were 29 deaths (21.6%). Eighteen patients died of septic shock (mainly bacterial pneumonia), whereas four died of alveolar hemorrhage, four of myocardial infarction, and three of other causes. In summary, our data from a very large retrospective and descriptive study mirrored the main clinical features of WG described in other countries, demonstrating that they may serve as a reference for South American populations.

Gas-surface interactions in the thermal and sub-thermal regime: A molecular dynamics study

Molecular dynamics simulations are used to study the interaction of low-energy Ar atoms with the Ni(001) surface, Angular scattering distributions, in and out of the plane of incidence, are investigated as a function of incident energy, angles of incidence, crystallographic orientation of the incident beam and surface temperature. The results show a clear transition to the structure scattering regime at around 2 eV. However, at lower energies, two sub-regimes are revealed by the simulations, Far energies up to 250 meV, scattering is mainly diffuse, and significant trapping on the surface is observed, At energies above this level, lobular patterns start to form and trapping decreases with the increase in energy, Generally, there is a weak temperature dependence, but variations in the angle of incidence and/or changes in the crystallographic direction, generate significant changes in the scattering patterns.

Abnormal expression of telomerase/apoptosis limits type II alveolar epithelial cell replication in the early remodeling of usual interstitial pneumonia/idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis is a distinctive, usually fatal, type of chronic fibrosing interstitial pneumonia of unknown cause that increases in prevalence with advanced age, characterized by failure of alveolar re-epithelization and progressive scar formation. Recently, limitation of the replicative capacity of tissues determined by telomerase/apoptosis balance has been implicated in pathogenesis of age-related diseases. In this study, we validated the importance of the expression of type 2 alveolar epithelial cells telomerase protein and studied the relationships between telomerase and apoptosis in early remodeling of usual interstitial pneumonia. We determined type 2 alveolar epithelial cells density, telomerase expression, and apoptosis in surgical lung biopsies from 24 patients with usual interstitial pneumonia, and in normal lung tissues from 18 subjects. We used immunohistochemistry, deoxynucleotidyl transferase method of end labeling, electron microscopy, and histomorphometry to evaluate the amount of type 2 alveolar epithelial cells staining for surfactant-A, telomerase, and in situ detection of apoptotic cells. Unaffected areas of usual interstitial pneumonia and normal lung tissue had similar densities of type 2 alveolar epithelial cells, but a significant minor subpopulation of type 2 alveolar epithelial cells was telomerase positive and a large population was telomerase negative. A significant inverse association was found between low type 2, alveolar. epithelial cell telomerase expression and high apoptosis in unaffected areas of usual interstitial pneumonia. Although type 2 alveolar epithelial cell telomerase expression was higher than apoptosis in NLT group, no significant association was found between them. Electron microscopy confirmed epithelial apoptosis, alveolar collapse, and initial fibroplasia. We conclude that abnormal type 2 alveolar epithelial cells telomerase/apoptosis balance may reduce alveolar epithelial regenerative capacity, thus contributing to the early remodeling response in usual interstitial pneumonia. (C) 2010 Elsevier Inc. All rights reserved.

Congenic strains provide evidence that four mapped loci in chromosomes 2, 4, and 16 influence hypertension in the SHR

Aneas I, Rodrigues MV, Pauletti BA, Silva GJ, Carmona R, Cardoso L, Kwitek AE, Jacob HJ, Soler JM, Krieger JE. Congenic strains provide evidence that four mapped loci in chromosomes 2, 4, and 16 influence hypertension in the SHR. Physiol Genomics 37: 52-57, 2009. First published January 6, 2009; doi: 10.1152/physiolgenomics.90299.2008. - To dissect the genetic architecture controlling blood pressure (BP) regulation in the spontaneously hypertensive rat (SHR) we derived congenic rat strains for four previously mapped BP quantitative trait loci (QTLs) in chromosomes 2, 4, and 16. Target chromosomal regions from the Brown Norway rat (BN) averaging 13 - 29 cM were introgressed by marker-assisted breeding onto the SHR genome in 12 or 13 generations. Under normal salt intake, QTLs on chromosomes 2a, 2c, and 4 were associated with significant changes in systolic BP (13, 20, and 15 mmHg, respectively), whereas the QTL on chromosome 16 had no measurable effect. On high salt intake (1% NaCl in drinking water for 2 wk), the chromosome 16 QTL had a marked impact on SBP, as did the QTLs on chromosome 2a and 2c (18, 17, and 19 mmHg, respectively), but not the QTL on chromosome 4. Thus these four QTLs affected BP phenotypes differently: 1) in the presence of high salt intake (chromosome 16), 2) only associated with normal salt intake (chromosome 4), and 3) regardless of salt intake (chromosome 2c and 2a). Moreover, salt sensitivity was abrogated in congenics SHR. BN2a and SHR. BN16. Finally, we provide evidence for the influence of genetic background on the expression of the mapped QTLs individually or as a group. Collectively, these data reveal previously unsuspected nuances of the physiological roles of each of the four mapped BP QTLs in the SHR under basal and/or salt loading conditions unforeseen by the analysis of the F2 cross.

Effect of body composition at selection on reproductive development in large white gilts

Fifty-four Large White gilts were used to determine the effect of body composition at selection (145 d of age) on the onset of puberty and subsequent reproductive development until 202 d of age. Gilts were assigned to one of three groups based on their backfat depth at selection: 10 to 12 mm (L), 13 to 15 mm (M), and 16 to 18 mm (F). All of the F gilts, 92% of the M gilts, and 67% of the L gilts reached puberty by slaughter at 202 d of age. Data from a subgroup (first 67% to reach puberty in each group; L = Lp, M = Mp, and F = Fp) was also used. The M (Mp) and F (Fp) gilts reached puberty at 172 d (166 d) and 170 d (166 d) of age, respectively, but the L (Lp) gilts at 184.5 d were 12 d (18 d) older than M(P < .05), Mp(P < .001), and F(P < .01), Fp (P < .001) gilts. The Lp (97.68 kg) and Mp (98.33 kg) gilts were lighter (P < .01) than Fp (108.72 kg) gilts at puberty. There were no differences (P < .05) among the L, M, and F gilts in terms of backfat depth or weight at puberty. The L (Lp) gilts had a mean of 1.16 (1.75) estrous cycles, which was lower (P < .01) than for M (Mp) and (P < .01) F (Fp) gilts, with 1.96 (2.29) and 2.25 (2.33) cycles, respectively. L (Lp) gilts had fewer (P < .05) follicles, 13.14 (12.63), than either M (Mp), 19.08 (18.71), or F (Fp), 18.25 (17.42) gilts. The number of corpora lutea was not influenced (P > .05) by grouping at selection, but Fp gilts had fewer (P < .05) corpora lutea than Mp or Fp gilts. Live weight at slaughter was not influenced (P > .10) by grouping at selection or subgrouping at puberty. The L gilts with a mean of 18.05 mm of backfat at slaughter were leaner (P < .05) than the F (21.66 mm) but not (P > .10) the M gilts (19.41 mm). Subgrouping had no effect. Fat deposition and protein deposition were higher (P < .05) in those animals that attained puberty. We conclude that the rate of fat and protein deposition seems to be one of the determinants of puberty attainment.

Immediate early gene expression and delayed cell death in limbic areas of the rat brain after kainic acid treatment and recovery in the cold

Systemic injection of kainic acid (KA) results in characteristic behaviors and programmed cell death in some regions of the rat brain. We used KA followed by recovery at 4 degrees C to restrict damage to limbic structures and compared patterns of immediate early gene (IEG) expression and associated DNA binding activity in these damaged areas with that in spared brain regions. Male Wistar rats were injected with BA (12 mg/kg, ip) and kept at 4 degrees C for 5 h. This treatment reduced the severity of behaviors and restricted damage (observed by Nissl staining) to the CA1 and CA3 regions of the hippocampus and an area including the entorhinal cortex. DNA laddering, characteristic of apoptosis, was first evident in the hippocampus and the entorhinal cortex 18 and 22 h after RA, respectively. The pattern of IEG mRNA induction fell into three classes: IEGs that were induced in both damaged and spared areas (c-fos, fos B, jun B, and egr-1), IEGs that were induced specifically in the damaged areas (fra-2 and c-jun), and an IEG that was significantly induced by saline injection and/or the cold treatment (jun D). The pattern of immunoreactivity closely followed that of mRNA expression. Binding to the AP-1 and EGR DNA consensus sequences increased in all three regions studied. This study describes a unique modification of the animal model of ICA-induced neurotoxicity which may prove a useful tool for dissecting the molecular cascade that ultimately results in programmed cell death. (C) 1997 Academic Press.

Basilar artery occlusive disease in stroke survivors in a multiethnic population

Objectives: To describe clinical, radiological findings, and outcome in a multiethnic population of stroke survivors with basilar artery occlusive disease (BAOC). Methods: Forty patients with infarcts in the basilar artery (BA) territory, alive 30 days after the ictus, participated in the study. BA stenosis (>50%) or occlusion was shown by magnetic resonance or digital subtraction angiography in all patients. Demographical, clinical and radiological characteristics were described. Modified Rankin Scale (MRS) scores at 30 days and 6 months after the ischemic event were evaluated. Association between demographical, clinical, radiological features and outcome were analyzed with Chi-square and Fisher`s exact tests. MRS scores at 30 days and 6 months were compared with the Wilcoxon test. Results: Sixty percent of the patients were men, and 33% were Afro-Brazilian. Mean age was 55.8 +/- 12.9 years. Most (90%) had multiple vascular risk factors. Stroke was preceded by TIA in 48% of the patients, and 80% had a history of arterial hypertension. The most common neurological symptom was vertigo/dizziness (60%) and the sign, hemiparesis (60%). Most of the infarcts were located in the pons (85%) and the BA middle third was the most frequently affected segment (33%). BA occlusion occurred in 58% of the patients. More severe vascular occlusive lesions were present in Whites (p = 0.002) and in patients with involvement of the middle third of the BA (p = 0.021). Large-artery atherosclerosis was the most common stroke etiology (88%) and was more frequent in older patients (p < 0.001). Most patients were treated with anticoagulation. MRS scores improved significantly at 6 months (p < 0.001): at this time, 78% of the patients had MRS scores between 0 and 2. Conclusions: We observed different results compared with other series: greater proportion of Afro-descendents, higher frequency of atherosclerosis and BA occlusion. Rates of preceding TIAs and good outcome at 6 months were similar to previously published data. These results represent a step forward towards understanding BAOC in a multiethnic context. (C) 2009 Elsevier B.V. All rights reserved.

Cortical Thickness Reduction of Normal Appearing Cortex in Patients with Polymicrogyria

OBJECTIVE To examine cortical thickness and volumetric changes in the cortex of patients with polymicrogyria, using an automated image analysis algorithm. METHODS Cortical thickness of patients with polymicrogyria was measured using magnetic resonance imaging (MRI) cortical surface-based analysis and compared with age-and sex-matched healthy subjects. We studied 3 patients with disorder of cortical development (DCD), classified as polymicrogyria, and 15 controls. Two experienced neuroradiologists performed a conventional visual assessment of the MRIs. The same data were analyzed using an automated algorithm for tissue segmentation and classification. Group and individual average maps of cortical thickness differences were produced by cortical surface-based statistical analysis. RESULTS Patients with polymicrogyria showed increased thickness of the cortex in the same areas identified as abnormal by radiologists. We also identified a reduction in the volume and thickness of cortex within additional areas of apparently normal cortex relative to controls. CONCLUSIONS Our findings indicate that there may be regions of reduced cortical thickness, which appear normal from radiological analysis, in the cortex of patients with polymicrogyria. This finding suggests that alterations in neuronal migration may have an impact in the cortical formation of the cortical areas that are visually normal. These areas are associated or occur concurrently with polymicrogyria.

Microvascular Lymphatic Density Analysis in Cutaneous Regressive and Nonregressive Superficial Spreading Melanomas Using the Lymphatic Marker D2-40

Background: The prognostic significance of spontaneous regression in melanoma, especially thin lesions, has been a controversial issue for the past 20 years, although recent studies suggest that extensive and late regression may be related to worse prognosis. Many data suggest that lymphangiogenesis predicts metastatic spread in melanoma. Methods: We have quantified lymphatic microvascular density (LMVD) in thin (<= 1.0 mm) superficial spreading melanomas comparing regressive and nonregressive melanomas, regressive and nonregressive areas from the same tumor, and early and late histological stages of regression in the same tumor. In addition, we tried to correlate lymphangiogenesis and tumor growth phase. We conducted histological examinations and immunohistochemical analyses using monoclonal antibody D2-40 with subsequent quantification by image analysis of 37 melanomas, 16 regressive and 21 nonregressive (controls). Results: We found higher LMVD in the late stage of regression compared with nonregressive area (internal control) of regressive melanomas. Conclusions: Our study suggest that the late stage of spontaneous regression in thin melanomas may be related to worse prognosis as it showed higher LMVD, and evidence shows that this is related with increased risk of metastatic spread. But this supposition must be confirmed by a longer follow-up for detection of lymph node metastases.

Leprosy in transplant recipients: report of a case after liver transplantation and review of the literature

P>Leprosy still is an important public health problem in several parts of the world including Brazil. Unlike the diseases caused by other mycobacteria, the incidence and clinical presentation of leprosy seems little affected in immunosuppressed patients. We report the first case, to our knowledge, of a liver transplant patient who developed multi-bacillary leprosy. The patient presented with papules and infiltrated plaques with loss of sensation suggestive of leprosy 3.5 years after living-related liver transplantation for autoimmune hepatitis. A skin biopsy showing non-caseating macrophagic granulomas, neuritis, and intact acid-fast bacilli on Fite-Faraco stain, confirmed the diagnosis of borderline lepromatous leprosy. The donor of the liver did not show any evidence of leprosy. During follow-up, the patient presented 2 episodes of upgrading leprosy type I reactions, 1 mild before leprosy treatment, and 1 moderate 3 months after receiving standard multi-drug treatment (rifampicin, clofazimine, and dapsone). These reactions were accompanied by increase in liver function tests, especially of canalicular enzymes. This reaction occurred despite the patient`s triple immunosuppression regimen. The moderate reaction was successfully treated with further immunosuppression (prednisone, 0.5 mg/kg). Currently, the patient is asymptomatic, off leprosy medication, with routine liver transplant follow-up. The dilemmas in diagnosis and management of such a case are discussed and the literature on leprosy in transplant recipients is reviewed.

Fatal acute respiratory distress syndrome in a patient with paracoccidioidomycosis: first case report

Paracoccidioidomycosis is a systemic mycosis that is usually acquired early in life by inhalation of conidia which convert in the lungs into yeast forms; these in turn trigger an inflammatory process. This mycosis may appear as an acute/subacute form or a chronic, adult form. Acute/subacute presentations can be observed in children and young adults, with the reticuloendothelial system frequently involved but the lungs are usually spared or present with mild clinical or radiological alterations. Acute respiratory distress syndrome (ARDS), an extensive dysfunction of the lungs alveolar-capillary barrier has occasionally been observed in other endemic mycoses such as coccidioidomycosis, cryptococcosis, histoplasmosis and blastomycosis. We describe the first patient with acute paracoccidioidomycosis who developed fatal ARDS accompanied by multiple organ injuries. The basis of the rarity of this entity in patients with paracoccidioidomycosis, as well as the reasons that may have lead to the development of ARDS in this patient are discussed.

Concomitant Lucio Phenomenon and Erythema Nodosum in a Leprosy Patient: Clues for Their Distinct Pathogeneses

Lepromatous leprosy patients may develop necrotic lesions, usually in the context of Lucio phenomenon (LP) or severe erythema nodosum (EN). The clinical and histopathological characteristics of the necrotic manifestations of both entities may eventually be confounded. We describe a patient with lepromatous leprosy who developed, since the 4th month of her first pregnancy, recurrent necrotic lesions in lower limbs, which, at the postpartum, worsened and led to partial destruction of ears and nose. In addition, she referred painful nodes oil upper limbs since I year before pregnancy and intermittent swelling and tenderness of the ankles, which together with a right tibial and ulnar neuritis led to the diagnosis of, erythema nodosum leprosum (ENL). The histopathology of a biopsy of the upper limb (ENL) revealed a dermal-hypodermal inflammation with vasculitis and vascular lumen narrowing, whereas biopsy of the lower limb (LP) revealed small vessels with fibrin thrombi on the superficial layer of the dermis without inflammatory infiltrate and no evidence of vasculitis. Thus, besides having several different clinical features, LP and ENL result from different pathogenetic mechanisms. The histopathological and clinical features distinguishing both entities are proposed. This distinction is important because decrease in bacillary load through multidrug therapy is the main target in LP, whereas in ENL, concomitant reduction of the reaction by means of thalidomide or high-dose steroids is recommended.