"Put Myself Into Your Place": Embodied Simulation and Perspective Taking in Autism Spectrum Disorders.

Embodied cognition theories hold that cognitive processes are grounded in bodily states. Embodied processes in autism spectrum disorders (ASD) have classically been investigated in studies on imitation. Several observations suggested that unlike typical individuals who are able of copying the model's actions from the model's position, individuals with ASD tend to reenact the model's actions from their own egocentric perspective. Here, we performed two behavioral experiments to directly test the ability of ASD individuals to adopt another person's point of view. In Experiment 1, participants had to explicitly judge the left/right location of a target object in a scene from their own or the actor's point of view (visual perspective taking task). In Experiment 2, participants had to perform left/right judgments on front-facing or back-facing human body images (own body transformation task). Both tasks can be solved by mentally simulating one's own body motion to imagine oneself transforming into the position of another person (embodied simulation strategy), or by resorting to visual/spatial processes, such as mental object rotation (nonembodied strategy). Results of both experiments showed that individual with ASD solved the tasks mainly relying on a nonembodied strategy, whereas typical controls adopted an embodied strategy. Moreover, in the visual perspective taking task ASD participants had more difficulties than controls in inhibiting other-perspective when directed to keep one's own point of view. These findings suggested that, in social cognitive tasks, individuals with ASD do not resort to embodied simulation and have difficulties in cognitive control over self- and other-perspective.

Specific mutations in the C-terminus domain of HBV surface antigen significantly correlate with low level of serum HBV-DNA in patients with chronic HBV infection.

BACKGROUND: To define HBsAg-mutations correlated with different serum HBV-DNA levels in HBV chronically-infected drug-naive patients. METHODS: This study included 187 patients stratified into the following ranges of serum HBV-DNA:12-2000 IU/ml, 2000-100,000 IU/ml, and >100,000 IU/ml. HBsAg-mutations were associated with HBV-DNA levels by applying a Bayesian-Partitional-Model and Fisher-exact test. Mutant and wild-type HBV genotype-D genomes were expressed in Huh7 cells and HBsAg-production was determined in cell-supernatants at 3 days-post-transfection. RESULTS: Specific HBsAg-mutations (M197T,-S204N-Y206C/H-F220L) were significantly correlated with serum HBV-DNA <2000 IU/ml (posterior-probability>90%, P < 0.05). The presence of Y206C/H and/or F220L was also associated with lower median (IQR) HBsAg-levels and lower median (IQR) transaminases (for HBsAg:250[115-840] IU/ml for Y206C/H and/or F220L versus 4300[640-11,838] IU/ml for wild-type, P = 0.023; for ALT:28[21-40] IU/ml versus 53[34-90] IU/ml, P < 0.001). These mutations were localized in the HBsAg C-terminus, known to be involved in virion and/or HBsAg secretion. The co-occurrence of Y206C + F220L was found significant by cluster-analysis, (P = 0.02). In addition, in an in-vitro model Y206C + F220L determined a 2.8-3.3 fold-reduction of HBsAg-amount released in supernatants compared to single mutants and wt (Y206C + F220L = 5,679 IU/ml; Y206H = 16,305 IU/ml; F220L = 18,368 IU/ml; Y206C = 18,680 IU/ml; wt = 14,280 IU/ml, P < 0.05). CONCLUSIONS: Specific HBsAg-mutations (compartmentalized in the HBsAg C-terminus) correlated with low-serum HBV-DNA and HBsAg-levels. These findings can be important to understand mechanisms underlying low HBV replicative potential including the inactive-carrier state.

Acute hepatitis C: a 24-week course of pegylated interferon α-2b versus a 12-week course of pegylated interferon α-2b alone or with ribavirin.

UNLABELLED: Therapy of acute hepatitis C (AHC) has not yet been standardized and several issues are still unresolved. This open, randomized, multicenter trial aimed to assess the efficacy and safety of a 24-week course of pegylated IFN (Peg-IFN) alpha-2b versus a 12-week course of Peg-IFN alpha-2b alone or with ribavirin (RBV) in AHC patients. One hundred and thirty HCV acutely infected patients who did not spontaneously resolve by week 12 after onset were consecutively enrolled and randomized to receive Peg-IFN alpha-2b monotherapy (1.5 µg/kg/week) for 24 or 12 weeks (arm 1, n = 44 and arm 2, n = 43, respectively) or in combination with RBV (10.6 mg/kg/day) for 12 weeks (arm 3, n = 43). The primary endpoint was undetectable HCV RNA at 6-month posttreatment follow-up (sustained virological response; SVR). All patients were followed for 48 weeks after therapy cessation. HCV RNA levels were determined by real-time polymerase chain reaction (limit of detection: 15 IU/mL) at the central laboratory at baseline, week 4, end of treatment, and 6 and 12 months posttreatment. Using an intent-to-treat analysis, overall SVR rate was 71.5%. In particular, an SVR was achieved in 31 of 44 (70.5%), 31 of 43 (72.1%), and 31 of 43 (72.1%) patients in arms 1, 2, and 3, respectively (P = 0.898). Sixteen patients (12.3%) prematurely discontinued therapy or were lost to follow-up; thus, sustained response rates with per-protocol analysis were 81.6%, 81.6%, and 81.6% for patients in arms 1, 2, and 3 respectively. With multivariate analysis, virologic response at week 4 of treatment was an independent predictor of SVR. Peg-IFN alpha-2b was well tolerated. CONCLUSION: Peg-IFN alpha-2b induces a high SVR in chronically evolving AHC patients. Response rates were not influenced by combination therapy or treatment duration.

Motor imagery in Asperger syndrome: testing action simulation by the hand laterality task.

Asperger syndrome (AS) is a neurodevelopmental condition within the Autism Spectrum Disorders (ASD) characterized by specific difficulties in social interaction, communication and behavioural control. In recent years, it has been suggested that ASD is related to a dysfunction of action simulation processes, but studies employing imitation or action observation tasks provided mixed results. Here, we addressed action simulation processes in adolescents with AS by means of a motor imagery task, the classical hand laterality task (to decide whether a rotated hand image is left or right); mental rotation of letters was also evaluated. As a specific marker of action simulation in hand rotation, we assessed the so-called biomechanical effect, that is the advantage for judging hand pictures showing physically comfortable versus physically awkward positions. We found the biomechanical effect in typically-developing participants but not in participants with AS. Overall performance on both hand laterality and letter rotation tasks, instead, did not differ in the two groups. These findings demonstrated a specific alteration of motor imagery skills in AS. We suggest that impaired mental simulation and imitation of goal-less movements in ASD could be related to shared cognitive mechanisms.

Anti-HBV treatment induces novel reverse transcriptase mutations with reflective effect on HBV S antigen.

INTRODUCTION: The identification of novel reverse-transcriptase (RT) drug-resistance mutations is critical in predicting the probability of success to anti-HBV treatment. Furthermore, due to HBV-RT/HBsAg gene-overlap, they can have an impact on HBsAg-detection and quantification. METHODS: 356 full-length HBV-RT sequences from 197 drug-naive patients and 159 patients experiencing virological-breakthrough to nucleoside/nucleotide-analogs (NUCs) were analyzed. Mutants and wild-type HBs-antigens were expressed in HuH7-hepatocytes and quantified in cell-supernatants and cell-lysates by Architect HBsAg-assay. RESULTS: Ten novel RT-mutations (rtN53T-rtS78T-rtS85F-rtS135T-rtA181I-rtA200V-rtK212Q-rtL229V/F-rtM309K) correlated with specific NUC-treatments and classical drug-resistance mutations on divergent evolutionary pathways. Some of them reduced RT-binding affinity for anti-HBV drugs and altered S-antigen structure. Indeed, rtS78T (prevalence: 1.1% in drug-naïve and 12.2% in adefovir-failing patients) decreased the RT-affinity for adefovir more than the classical adefovir-resistance mutations rtA181 T/V (WT:-9.63 kcal/mol, rtA181T:-9.30 kcal/mol, rtA181V:-7.96 kcal/mol, rtS78T:-7.37 kcal/mol). Moreover, rtS78T introduced a stop-codon at HBsAg-position 69, and completely abrogated HBsAg-quantification in both supernatants and cell-lysates, indicating an impaired HBsAg-secretion/production. Furthermore, the HBsAg-mutation sP217L, silent in RT, significantly correlated with M204V/I-related virological-breakthrough and increased HBsAg-quantification in cell-lysate. CONCLUSIONS: Mutations beyond those classically known can affect drug-binding affinity of mutated HBV-RT, and may have potential effects on HBsAg. Their cumulative effect on resistance and HBV-pathogenicity indicates the importance of preventing therapeutic failures.

Role of hepatitis B virus genetic barrier in drug-resistance and immune-escape development.

BACKGROUND: Impact of hepatitis B virus genetic barrier, defined as the number and type of nucleotide substitutions required to overcome drug/immune selective pressure, on drug-resistance/immune-escape development is unknown. METHODS: Genetic barrier was calculated according to Van de Vijver (2006) in 3482 hepatitis B virus-reverse transcriptase/HBV surface antigen sequences from 555 drug-naïve patients and 2927 antiviral-treated patients infected with hepatitis B virus genotypes A-G. RESULTS: Despite high natural variability, genetic barrier for drug-resistance development is identical amongst hepatitis B virus genotypes, but varies according to drug-resistance mutation type. Highest genetic barrier is found for secondary/compensatory mutations (e.g. rtL80I/V-rtL180M-rtV173L), whilst most primary mutations (including rtM204V-rtA181T/V-rtI169T-rtA194T) are associated with low genetic barrier. An exception is rtM204I, which can derive from a transition or a transversion. Genotypes A and G are more prone to develop immune/diagnostic-escape mutations sT114R and sG130N. Vaccine-escape associated sT131N-mutation is a natural polymorphism in both A and G genotypes. CONCLUSION: Genetic barrier and reverse transcriptase/HBV surface antigen overlapping can synergistically influence hepatitis B virus drug-resistance/immune-escape development. The different immune-escape potential of specific hepatitis B virus genotypes could have important clinical consequences in terms of disease progression, vaccine strategies and correct HBV surface antigen detection.

Hepatitis C infection on immune recovery in HIV-positive patients on successful HAART: the role of genotype 3.

OBJECTIVE: The primary objective of this study was to investigate the impact of HCV infection and of HCV genotypes on immune restoration in HIV-infected patients on a successful HAART regimen. METHODS: Patients from the MASTER Study were included in this current longitudinal study if they met the following criteria: being on any successful HAART, availability of CD4+ cell count and HIV RNA level before starting the suppressive HAART and 12 months after suppressive therapy, availability of HCV antibodies. The primary endpoints of the study were defined as achieving a difference above 100 cell/mmc between CD4+ at baseline and at time of HIV RNA suppression while on therapy (DeltaCD4+early), or 12 month after a suppressive therapy (DeltaCD4+late). RESULTS: 844 HIV-positive patients were included in the analysis: 673 were HCV-negative and 171 were HCV-positive [92 (53.8%) subjects had HCV genotype 1; 58 (33.9%), genotype 3; 21 (12.3%), genotype 4]. Plasma HIV RNA (both baseline as highest value), nadir CD4+, being naïve, time to reach undetectable plasma HIV RNA, treatment with PI vs NNRTI were associated with an early immunological recovery; the occurrence of previous AIDS event, a history of injection drug use, and HCV infection were associated with failure to achieve an early immunological recovery. Variables associated with DeltaCD4+late immune recovery were baseline CD4+ value, plasma HIV RNA (both baseline as highest value), being naïve and time to reach undetectable plasma HIV RNA. HCV infection per se was not associated with a worse probability to reach late immunologic response, although among HCV infected patients, having a genotype 3 was associated with a worse immune recovery. At multivariable analysis, factors that remained associated with failure to achieve an early immunological response were being HCV infected and history of injection drug use, while those associated with a failure to achieve a late immunological response were being infected with HCV genotype 3 and older age. CONCLUSIONS: A blunted early immune recovery was observed in HCV infected patients, compared with HCV negative subjects, while late immune recovery was not different among HCV infected as a whole and not infected subjects; only the subgroup of subjects infected with genotype 3 showed an impaired late immune recovery.

Evolution of hepatitis C virus non-structural 5A gene in the progression of liver disease to hepatocellular carcinoma.

BACKGROUND: The interaction between the hepatitis C virus (HCV) non-structural 5A (NS5A) protein of HCV and the protein kinase R (PKR), which is an effector of the cellular antiviral response and has been defined as a tumour suppressor, may affect the control of protein synthesis and cell growth. AIM: We investigated the genetic evolution of the NS5A region in the NS5A PKR-binding domain (NS5A-PKRbd) of patients with HCV 1b-related cirrhosis who subsequently developed or not hepatocellular carcinoma (HCC). PATIENTS AND METHODS: The quasispecies composition of NS5A-PKRbd was inferred by sequencing an average of 15 clones per sample in specimens obtained from 26 patients with cirrhosis who developed or not HCC during a follow-up of 5 years. RESULTS: At baseline, 13/17 patients with final HCC and six out of nine patients with cirrhosis who subsequently did not develop HCC harboured a wild-type (wt) strain master sequence. Over time, the prevalence of wt strain was higher in patients who developed HCC with respect to those who maintained the cirrhosis status (15/17 vs 4/9, respectively; P=0.0166). CONCLUSION: The maintenance of or evolution to the wt strain of the NS5A domain in cirrhotic patients with final HCC highlights the central role of NS5A protein in the viral life cycle and in the progression of liver disease.

Pegylated interferon alfa-2b plus ribavirin in the retreatment of interferon-ribavirin nonresponder patients.

BACKGROUND & AIMS: Inadequate data are available about retreatment of nonresponders to interferon (IFN) and ribavirin. Thus, this study evaluated the efficacy and tolerability of a 48-week therapy with pegylated IFN-alpha-2b plus high-dose ribavirin in patients who have failed to respond to the combination. Treatment up to 48 weeks also in patients who have failed to clear hepatitis C virus (HCV) RNA by week 24 was also evaluated. METHODS: One hundred forty-one patients who previously did not respond to IFN and ribavirin, 86% with genotype 1 or 4 infection, 52% with high viral load (>800.000 IU/mL), 22% with cirrhosis, were retreated with pegylated IFN-alpha-2b 1.5 microg/kg per week and ribavirin 1000-1200 mg/day for 48 weeks and followed up for 24 weeks. RESULTS: By intent-to-treat analysis, 20% of patients achieved a sustained virologic response (SVR). SVR of genotype 1 patients was 19%. Independent predictors of SVR were low gamma-glutamyltransferase levels (OR, 22.9; 95% CI: 6.6-79.6) and low viral load (OR, 3.8; 95% CI: 1.1-12.6). Twelve (23%) out of 51 patients who were HCV RNA positive after 24 weeks of therapy achieved a late virologic response (after week 24) and 5 (10%) of them, all with genotype 1, achieved an SVR. Genotype was not associated with response (P = .2) or with early response (P = .3). CONCLUSIONS: Retreatment with pegylated IFN-alpha-2b and ribavirin of multi-experienced and "difficult to treat" nonresponder patients produced a very promising SVR. Accurate selection of patients, such as those with low viral load and low gamma-glutamyltransferase levels, and prolongation of therapy beyond 24 weeks also in HCV RNA-positive patients may further increase the rate of SVR.