Thrombin generation in plasma from patients with cirrhosis supplemented with normal plasma: considerations on the efficacy of treatment with fresh-frozen plasma

Cirrhosis is characterized by a complex coagulation defect leading to the prolongation of the prothrombin and activated partial thromboplastin times (PT and APTT). Arbitrary PT cut-off values are still used as a yardstick to guide treatment with fresh-frozen plasma (FFP) or other pro-coagulant agents in patients undergoing invasive procedures. No randomized studies on the FFP efficacy are available, and are unlikely to be carried out because of their complex organization. An interim solution could be to evaluate the in vitro thrombin generation in plasmas from patients with cirrhosis when mixed with appropriate amounts of pooled normal plasma (PNP). The PT, APTT and thrombin generations in the presence of thrombomodulin were examined in 58 patients with cirrhosis and 24 healthy subjects both before and after mixing their plasmas with PNP at a proportion of 4 + 1 (patient + PNP), chosen to mimic in vivo conditions when patients are treated with 10 ml/kg of FFP. The PT and APTT, which were abnormal in the majority of unmixed patient plasmas were shortened considerably, but did not normalize completely when mixed with PNP. Thrombin generation, which was already within normal limits in all unmixed patient plasmas, remained essentially unchanged after mixing with PNP. In conclusion, thrombin generation in patients with cirrhosis does not appreciably change after in vitro addition of PNP despite PT and APTT shortening would suggest otherwise. These results question the validity of the PT as a stand-alone test to guide transfusion of FFP in the setting of chronic liver disease.

A trans-specific polymorphism in ZC3HAV1 is maintained by long-standing balancing selection and may confer susceptibility to multiple sclerosis

The human ZC3HAV1 gene encodes an antiviral protein. The longest splicing isoform of ZC3HAV1 contains a C-terminal PARP-like domain, which has evolved under positive selection in primates. We analyzed the evolutionary history of this same domain in humans and in Pan troglodytes. We identified two variants that segregate in both humans and chimpanzees; one of them (rs3735007) does not occur at a hypermutable site and accounts for a nonsynonymous substitution (Thr851Ile). The probability that the two trans-specific polymorphisms have occurred independently in the two lineages was estimated to be low (P = 0.0054), suggesting that at least one of them has arisen before speciation and has been maintained by selection. Population genetic analyses in humans indicated that the region surrounding the shared variants displays strong evidences of long-standing balancing selection. Selection signatures were also observed in a chimpanzee population sample. Inspection of 1000 Genomes data confirmed these findings but indicated that search for selection signatures using low-coverage whole-genome data may need masking of repetitive sequences. A case–control study of more than 1,000 individuals from mainland Italy indicated that the Thr851Ile SNP is significantly associated with susceptibility to multiple sclerosis (MS) (odds ratio [OR] = 1.47, 95% confidence intervals [CI]: 1.08–1.99, P = 0.011). This finding was confirmed in a larger sample of 4,416 Sardinians cases/controls (OR = 1.18, 95% CI: 1.037–1.344, P = 0.011), but not in a population from Belgium. We provide one of the first instances of human/chimpanzee trans-specific coding variant located outside the major histocompatibility complex region. The selective pressure is likely to be virus driven; in modern populations, this variant associates with susceptibility to MS, possibly via the interaction with environmental factors.

Incidence, risk factors and clinical implications of venous thromboembolism in cancer patients treated within the context of phase I studies: the 'SENDO experience'

BACKGROUND

To investigate the incidence, risk factors and clinical implications of venous thromboembolism (VTE) in advanced cancer patients treated in phase I studies.

PATIENTS AND METHODS

Patients enrolled and treated in phase I studies conducted by SENDO (Southern Europe New Drugs Organization) Foundation between 2000 and 2010 in 15 experimental centers were considered for the study. Clinical data, including adverse events, were prospectively collected during the studies and retrospectively pooled for VTE analysis.

RESULTS

Data of 1415 patients were considered for analysis. Five hundred and twenty-six (37.2%) patients were males, and median age was 57.3 years (range: 13-85). Eighty-five percent of patients had metastatic disease, while the remaining had locally advanced irresectable disease. For 706 (49.9%) of the patients, the study treatment was with cytotoxic agent(s) only, for 314 with target therapy(ies) only, while the remaining patients received a target therapy in combination with a cytotoxic drug. Fifty-six (3.96%) patients who developed a VTE, almost all (89.3%) during the course of treatment, the remaining during the follow-up. At univariate analysis, the Khorana score, the combination of an antiangiogenic agent with a cytotoxic drug, and the time from first cancer diagnosis to study entry (as continuous variable) were associated with a statistically significant increase of VTE occurrence. The multivariate analysis confirmed only a statistically significant association for the Khorana score. The hazard ratio of VTE occurrence was 7.88 [95% confidence interval (CI) 2.86-21.70) and 2.74 (95% CI 1.27-5.92) times higher for the highest (≥3) and intermediate (1-2) scores as compared with score = 0.

CONCLUSIONS

VTE is a relatively common complication among patients treated in the context of phase I studies. The Khorana score predicts VTE development and can be used to identify patients at high of VTE.

Do they actually work across borders? Evaluation of two measures of psychological distress as screening instruments in a non Anglo-Saxon country

Screening scales can be useful in searching for common mental disorders in primary care and in tracking relevant prevalence and correlates in community surveys. However, it is important to document their validity, before using them. We developed Italian versions of the widely-used K10 and K6 screening scales following the WHO forward-translation and back-translation protocol. To evaluate their effectiveness as screens for DSM-IV 12-month mood or anxiety disorders and "serious mental illness" (SMI), the scales were validated in a two-stage clinical reappraisal survey. In the first-phase, the scales were administered to 605 people. In the second-phase, a sub-sample of 147 first-phase respondents over-sampling screened positives was administered the 12-month version of the Structured Clinical Interview for DSM-IV Axis I Disorders as a clinical gold standard. Performance of the scales in screening for chosen disorders was assessed by calculating area under the receiver operating characteristic curve and stratum-specific likelihood ratios. Both the K10 and K6 performed well in detecting DSM-IV mood disorders, anxiety disorders, and serious mental illness (SMI), with areas under the curve (AUCs) (95% CIs) between 0.82 (0.75-0.89) and 0.91 (0.85-0.96). The Italian versions of the K6 and K10 scales have good psychometric properties, making them attractive inexpensive screens for mood disorders, anxiety disorders, and SMI.

[General practitioners and colorectal cancer screening: experience in the Trentino region]

The aims of this longitudinal study are to investigate general practitioners' opinions and knowledge about colorectal cancer screening in Trentino region, to identify their role and level of participation within the screening program and to find out their formative needs. 174 general practitioners answered the postal self-filled questionnaire: 82% of them asserted their main role in colorectal screening is patient counselling, but many physicians also showed availability to collaborate with the Centre for Health Services of Trento in organizing patients recruitment list and in recovering patients who didn't accept screening invitation. 78% thinks the Health Services of Trento should allocate incentives, especially push money, to promote physicians participation in screening program. Moreover 68% needs a basic formative course about screening programme. Female general practitioners are more prepared to collaborate in organizing patients recruitment list and in handing over the kit for fecal occult blood test than their male colleagues. Instead men prefer to take an active role in counselling and are more interested in economic incentives. The study has found considerable general practitioners support for the introduction of the new screening programme. The info-formative line to improve in Trentino could create a better interface between general practitioners and Centre for Health Services, keeping into account the organizing features of physicians. It seems to be important the definition of shared procedures for the counselling and the requirement of formative courses by general practitioners; the Centre for Health Services of Trento has already undertaken these courses disguised as seminars addressed all health operators.

Hawking radiation from ultrashort laser pulse filaments

Event horizons of astrophysical black holes and gravitational analogues have been predicted to excite the quantum vacuum and give rise to the emission of quanta, known as Hawking radiation. We experimentally create such a gravitational analogue using ultrashort laser pulse filaments and our measurements demonstrate a spontaneous emission of photons that confirms theoretical predictions.

Space-time focusing of Bessel-like pulses

We report on a space-time compression technique allowing for complete and independent control of the longitudinal dynamics and of the transverse pulse localization by means of spatial beam shaping. We experimentally observe both strong temporal compression and high transverse localization, of the order of a few wavelengths, along free-space propagation.

Long-term balancing selection maintains trans-specific polymorphisms in the human TRIM5 gene

The human TRIM5 genes encodes a retroviral restriction factor (TRIM5α). Evolutionary analyses of this gene in mammals have revealed a complex and multifaceted scenario, suggesting that TRIM5 has been the target of exceptionally strong selective pressures, possibly exerted by recurrent waves of retroviral infections. TRIM5 displays inter-individual expression variability in humans and high levels of TRIM5 mRNA have been associated with a reduced risk of HIV-1 infection. We resequenced TRIM5 in chimpanzees and identified two polymorphisms in intron 1 that are shared with humans. Analysis of the gene region encompassing the two trans-specific variants in human populations identified exceptional nucleotide diversity levels and an excess of polymorphism compared to fixed divergence. Most tests rejected the null hypothesis of neutral evolution for this region and haplotype analysis revealed the presence of two deeply separated clades. Calculation of the time to the most recent common ancestor (TMRCA) for TRIM5 haplotypes yielded estimates ranging between 4 and 7 million years. Overall, these data indicate that long-term balancing selection, an extremely rare process outside MHC genes, has maintained trans-specific polymorphisms in the first intron of TRIM5. Bioinformatic analyses indicated that variants in intron 1 may affect transcription factor-binding sites and, therefore, TRIM5 transcriptional activity. Data herein confirm an extremely complex evolutionary history of TRIM5 genes in primates and open the possibility that regulatory variants in the gene modulate the susceptibility to HIV-1.

Severe hemophilia with mild bleeding phenotype: molecular characterization and global coagulation profile

BACKGROUND

Patients with severe hemophilia may show very varied bleeding tendencies, and the reasons for this heterogeneous clinical expression are unclear. The factor VIII/FIX genotype is the main determinant of the residual factor activity; however, different bleeding phenotypes have also been reported in patients sharing the same mutation. Such global coagulation tests as thrombin generation assays are tools with which to investigate different coagulation profiles among severe hemophiliacs.

OBJECTIVES, PATIENTS AND METHODS

This case-control study was aimed at comprehensively evaluating the role of genotype and endogenous thrombin potential (ETP) as predictors of the clinical phenotype in severe hemophiliacs with an extremely mild bleeding tendency (cases, n = 22), in comparison with those showing a typical bleeding tendency (controls, n = 50).

RESULTS

Cases were more frequently affected by hemophilia B than by hemophilia A, and showed a lower incidence of severe FVIII/FIX gene defects (referred to as null mutations), higher FVIII and FIX antigen levels and higher ETP values in platelet-rich plasma than controls (P < 0.05). By multivariate logistic regression, only non-null mutations were confirmed as an independent predictor of a mild clinical phenotype.

CONCLUSIONS

These results indicate that non-null mutations represent the main determinant of the bleeding tendency, and that ETP measurement in platelet-rich plasma is able to identify severe hemophiliacs with a mild clinical phenotype.

HLA-A*01 is associated with late onset of Alzheimer's disease in Italian patients

In this study, the distribution of HLA-A alleles was analyzed in Italian Alzheimer's Disease (AD)patients. Interaction between HLA alleles, APOE genotypes, age of onset, and gender were also analyzed. The results were compared to those obtained in healthy controls (HC). One hundred-seventy-three AD patients and 258 age-and-sex-matched healthy controls were enrolled in the study. AD patients were classified according to age at the onset of disease using quartiles of the distribution. HLA-A genotyping was performed by PCR-SSP; APOE genotyping was performed by RFLP. A correlation between late disease onset and HLA-A*01 was observed. Thus, HLA-A*01, calculated as number of alleles, was significantly more present in patients with age of onset > 74.0 years than in HC (20% vs 10.5%; p=0.014); the distribution of this allele was skewed also in patients 68.1-74 years of age (16.3%), even if the difference did not reach statistical significance. The relative risk ratio (RRR) of AD onset calculated by a multinomial logistic regression adjusted for sex and presence of APOE-4 confirmed a significant association of HLA-A*01 with AD onset > 74.0 years of age (RRR=2.2; 95%CI: 1.1-4.6; p=0.033). A high RRR (2.04) was also present in patients 68.1-74 years (p=0.064). Lower age of disease onset did not correlate with HLA-A*01. Data herein suggest that the presence of HLA-A*01 results in delayed AD development, even in patients carrying APOE-4. These results could offer new insights into the etiopathogenesis of Alzheimer's disease.