Viral load at the time of liver transplantation and risk of hepatitis B virus recurrence.

Hepatitis B virus (HBV) recurrence after liver transplantation is significantly reduced by prophylaxis with hepatitis B immune globulins (HBIG) or antiviral drugs in nonreplicating patients and by the combination of both drugs in replicating patients. However, the load of HBV DNA, which defines replicating status in patients undergoing liver transplantation, remains unclear. This study analyzes the correlation between the viral load, tested with a single amplified assay, at the time of liver transplantation, and the risk of hepatitis B recurrence in 177 HBV carriers who underwent transplantation in a single center from 1990 to 2002. Overall, HBV relapsed after surgery in 15 patients (8.5%) with a 5- and 8-year actuarial rate of recurrence of 8% and 21%, respectively. After liver transplantation hepatitis B recurred in 9% of 98 selected subjects treated only with immune globulins and in 8% of 79 viremic patients who received immune globulins and lamivudine (P = NS). A linear correlation was observed between recurrence and viral load at the time of surgery. In transplant patients with HBV DNA higher than 100,000 copies/mL, 200-99,999 copies/mL, and DNA undetectable by amplified assay, hepatitis B recurred in 50%, 7.5%, and 0% of patients, respectively. Overall, a viral load higher than 100,000 copies/mL at the time of liver transplantation was significantly associated with hepatitis B recurrence (P = .0003). In conclusion, spontaneous or antiviral-induced HBV DNA viral load at the time of surgery classifies the risk of HBV recurrence after liver transplantation and indicates the best prophylaxis strategy.     

Detection of sonographic B-lines in patients with normal lung or radiographic alveolar consolidation.

BACKGROUND: Diffuse comet-tail B-line artifacts in lung ultrasound are a sign of alveolar-interstitial syndrome, but isolated transthoracic scans positive for B-lines (multiple B lines or B+) could be detected in other conditions. The aim was to assess the prevalence and distribution of this sonographic sign in patients with normal lung or isolated alveolar consolidation in chest radiography. MATERIAL/METHODS: Two hundred seventeen patients consecutively admitted to this emergency medicine unit with any diagnosis and without radiographic or clinical evidence of diffuse interstitial syndrome were analyzed. Each patient underwent chest radiography and lung sonographic examination with four anterolateral chest scans per side. RESULTS: Of the 1736 sonographic scans performed, 13.2% were positive for the B+ pattern. Positive scans significantly corresponded to laterobasal areas or radiographic opacities due to lung alveolar consolidations (p<0.005). Twenty percent of the laterobasal scans of 145 patients with radiologically normal lung were positive. The negative predictive value of B+ was 83.9% (95% confidence interval: 78.2-89.7%), with a specificity of 90.3% (95%CI: 85.5-95.1%) for predicting any localized radiographic pulmonary opacity. CONCLUSIONS: B+ scans can be detected in the chest areas surrounding an isolated alveolar consolidation and in the laterobasal scans of a radiographic normal lung. These features should always be considered when lung ultrasound is performed to rule out the alveolar-interstitial syndrome in an emergency setting. Moreover, B+ patterns have a satisfactory negative predictive value for radiographic lung opacities, which could have added diagnostic value in the ED evaluation of dyspneic patients.     

Extensive hydroa vacciniforme

Hydroa Vaciniforme is a very rare photodermatosis that is mainly seen in childhood.An 18 year old female student reported that since the age of 5 she has been sufferingnecrotic lesions and vesicles lesions in exposed areas, leaving asymptomaticvarioliform scars, which worsened in summer. Light microscopy showed epidermalnecrosis with lymphocytic infiltration. Sunscreens were prescribed with lightimprovement.     

The base excision repair enzyme MED1 mediates DNA damage response to antitumor drugs and is associated with mismatch repair system integrity

Cytotoxicity of methylating agents is caused mostly by methylation of the O6 position of guanine in DNA to form O6-methylguanine (O6-meG). O6-meG can direct misincorporation of thymine during replication, generating O6-meG:T mismatches. Recognition of these mispairs by the mismatch repair (MMR) system leads to cell cycle arrest and apoptosis. MMR also modulates sensitivity to other antitumor drugs. The base excision repair (BER) enzyme MED1 (also known as MBD4) interacts with the MMR protein MLH1. MED1 was found to exhibit thymine glycosylase activity on O6-meG:T mismatches. To examine the biological significance of this activity, we generated mice with targeted inactivation of the Med1 gene and prepared mouse embryonic fibroblasts (MEF) with different Med1 genotype. Unlike wild-type and heterozygous cultures, Med1-/- MEF failed to undergo G2-M cell cycle arrest and apoptosis upon treatment with the methylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Similar results were obtained with platinum compounds' 5-fluorouracil and irinotecan. As is the case with MMR-defective cells, resistance of Med1-/- MEF to MNNG was due to a tolerance mechanism because DNA damage accumulated but did not elicit checkpoint activation. Interestingly, steady state amounts of several MMR proteins are reduced in Med1-/- MEF, in comparison with Med1+/+ and Med1+/- MEF. We conclude that MED1 has an additional role in DNA damage response to antitumor agents and is associated with integrity of the MMR system. MED1 defects (much like MMR defects) may impair cell cycle arrest and apoptosis induced by DNA damage.     

Reduced folate carrier polymorphism (80A-->G) and neural tube defects

Transport of folates in mammalian cells occurs by a carrier-mediated mechanism. The human folate carrier (RFC-1) gene has been isolated and characterized. Within this gene, a common polymorphism, 80A-->G, changing a histidine to an arginine in exon 2 (H27R), was recently identified. Defects in folate metabolism, such as defective carrier molecules, could be implicated in the etiology of neural tube defects (NTDs). In the present case-control study, we recruited 174 Italian probands with nonsyndromic NTD, 43 mothers, 53 fathers and 156 control individuals and evaluated the impact of RFC-1 variant on NTD risk. A statistically significant risk was calculated for the 80GG genotype of the NTD cases (OR=2.35; 95% CI 1.21-4.58) and mothers (OR=2.74; 95% CI 0.92-8.38). On the contrary, the heterozygous genotype of the mothers and both heterozygous and homozygous genotypes of the fathers did not seem to be significant NTD risk factors. Furthemore, according to the multifactorial inheritance of NTDs, we demonstrated that the combined genotypes for MTHFR 1298A-->C and RFC-1 80A-->G polymorphisms of cases resulted in greater NTD risk than heterozygosity or homozygosity for RFC-1 80A-->G variant alone. Conversely, our data provide no evidence for an association between NTD phenotype and combined MTHFR C677T/RFC-1 A80G genotypes. Moreover, here we describe the combinations of the two MTHFR polymorphic sites (677CT and 1298AC) with RFC-1 genotypes. We found that both patients and controls could have at most quadruple-mutation combinations. Interestingly, 27% (7/26) of the mothers and 18.75% (30/160) of the cases genotyped presented four mutant alleles in comparison with 8.5% (11/129) of the controls. Finally, the frequency of NTD cases and mothers carrying combined heterozygosity for the two MTHFR polymorphisms and RFC-1 80GG homozygosity (677CT/1298AC/80GG) (cases=11.3%; mothers 11.5%) was increased compared with controls (1.6%). Altogether, our findings support the hypothesis that RFC-1 A80G variant may contribute to NTD susceptibility in the Italian population.     

Sequence-based typing of Legionella pneumophila serogroup 1 offers the potential for true portability in legionellosis outbreak investigation

Seven gene loci of Legionella pneumophila serogroup 1 were analyzed as potential epidemiological typing markers to aid in the investigation of legionella outbreaks. The genes chosen included four likely to be selectively neutral (acn, groES, groEL, and recA) and three likely to be under selective pressure (flaA, mompS, and proA). Oligonucleotide primers were designed to amplify 279- to 763-bp fragments from each gene. Initial sequence analysis of the seven loci from 10 well-characterized isolates of L. pneumophila serogroup 1 gave excellent reproducibility (R) and epidemiological concordance (E) values (R = 1.00; E = 1.00). The three loci showing greatest discrimination and nucleotide variation, flaA, mompS, and proA, were chosen for further study. Indices of discrimination (D) were calculated using a panel of 79 unrelated isolates. Single loci gave D values ranging from 0.767 to 0.857, and a combination of all three loci resulted in a D value of 0.924. When all three loci were combined with monoclonal antibody subgrouping, the D value was 0.971. Sequence-based typing of L. pneumophila serogroup 1 using only three loci is epidemiologically concordant and highly discriminatory and has the potential to become the new "gold standard" for the epidemiological typing of L. pneumophila.     

Severity of acute intracerebral haemorrhage,elderly age and atrial fibrillation: Independent predictors of poor outcome at three months

Background and purposePrognostic risk factors of haemorrhagic stroke are not yet fully identified. This study investigated clinical factors leading to poor outcome at three months in patients with intracerebral haemorrhage (ICH) in order to better understand the role of clinical features in prognostic evaluation.Subjects and methodsThis was a prospective cohort study on patients having ICH admitted to two Italian hospitals (the Stroke Units at “Ospedale Santa Maria della Misericordia“, Perugia and “Ospedale C. Poma“, Mantua) between January 1, 2006 and June 30, 2010.ResultsA total of 470 consecutive ICH patients (mean age 73.89 ± 13.02 years) were included and of these, 241 (51.1%) were males. At three months, 293 (62.3%) patients had poor outcome including 133 (27.6%) deaths. The resulting significant predictors of poor outcome from univariate analysis included: age, NIH Stroke Scale Score (NIHSSS) at admission, hyperglycaemia and the presence of atrial fibrillation (AF). These variables were confirmed in logistic regression analyses as being independent predictors of disability: age (OR 1.04 95% CI, 1.02–1.07, p = 0.0001), AF (OR 3.18 95% CI, 1.12–9.05 p = 0.03) and NIHSSS (OR 1.38 95% CI, 1.28–1.48, p = 0.0001), while elderly age (OR 1.10 95% CI, 1.06–1.14, p ≤ 0.0001) and high NIHSSS (OR 1.25 95% CI, 1.19–1.31, p ≤ 0.0001) resulted being independent predictors of mortality.ConclusionsThis study found that severity of ICH, elderly age and AF were independent predictors of poor outcome in ICH patients at three months. Thereby, this highlights the importance of understanding the roles of clinical features in ICH prognostic evaluation.     

Junctional adhesion molecule-C regulates vascular endothelial permeability by modulating VE-cadherin-mediated cell-cell contacts

We recently reported that junctional adhesion molecule (JAM)-C plays a role in leukocyte transendothelial migration. Here, the role of JAM-C in vascular permeability was investigated in vitro and in vivo. As opposed to macrovascular endothelial cells that constitutively expressed JAM-C in cell-cell contacts, in quiescent microvascular endothelial cells, JAM-C localized mainly intracellularly, and was recruited to junctions upon short-term stimulation with vascular endothelial growth factor (VEGF) or histamine. Strikingly, disruption of JAM-C function decreased basal permeability and prevented the VEGF- and histamine-induced increases in human dermal microvascular endothelial cell permeability in vitro and skin permeability in mice. Permeability increases are essential in angiogenesis, and JAM-C blockade reduced hyperpermeability and neovascularization in hypoxia-induced retinal angiogenesis in mice. The underlying mechanisms of the JAM-C-mediated increase in endothelial permeability were studied. JAM-C was essential for the regulation of endothelial actomyosin, as revealed by decreased F-actin, reduced myosin light chain phosphorylation, and actin stress fiber formation due to JAM-C knockdown. Moreover, the loss of JAM-C expression resulted in stabilization of VE-cadherin-mediated interendothelial adhesion in a manner dependent on the small GTPase Rap1. Together, through modulation of endothelial contractility and VE-cadherin-mediated adhesion, JAM-C helps to regulate vascular permeability and pathologic angiogenesis.     

No early signs of atherosclerotic alterations in carriers of inherited thrombophilia

BackgroundCongenital thrombophilia is a risk factor for venous thromboembolism (VTE). Whether it is associated with increased risk of arterial disease is today a matter of debate. We aimed to look for early signs of atherosclerotic alterations in carriers of inherited thrombophilic alterations (ITA).MethodsBetween January 2006 and September 2008 ultrasonography assessment of the carotid arteries with measurement of intima-media thickness (IMT), and determination of the ankle/brachial pressure index (ABI), was performed in: a) 161 carriers of ITA (deficiency of antithrombin, protein C or S, factor V Leiden or prothrombin G20210A mutations), 84 of whom with previous VTE, and b) 180 subjects without ITA, matched for age, sex and previous VTE. All subjects were < 66 year old.ResultsCarotid plaques were found in 8 subjects [3 (1.9%) with ITA]. Increased IMT values (> 1 mm) were detected in 6 subjects with and 1 without thrombophilia (p = 0.055). The prevalence of IMT values > 90^th percentile was not different in subjects with/without thrombophilia (15.2% vs 11.6%, p = 0.416). At multivariate analysis only age was significantly associated with increased odds ratios for IMT values > 90^th percentile. No subjects had abnormal (< 0.9) ABI values.ConclusionsThe present study, the first to investigate the presence of atherosclerotic markers in relatively young subjects with inherited thrombophilia, did not find a particular prevalence of signs of early atherosclerotic markers in these subjects.