Adjustment of optical absorption in phosphorene through electron-phonon coupling and an electric field.

This study investigates the optical absorption of monolayer phosphorene, focusing on its response to the electron-phonon coupling (EPC) and an electric field. Using a tight-binding Hamiltonian model based on the Barisic-Labbe-Friedel-Su-Schrieffer-Heeger model and the Kubo formula, we calculate the electronic band structure and optical absorption characteristics. The anisotropic dispersion of carriers along armchair and zigzag directions leads to distinct optical responses. Positive and negative EPC effects increase and decrease hopping parameters, respectively, enlarging and reducing/closing the band gap. Moreover, both EPCs cause an admixture of blue and red shift spectrum along the armchair direction, while a red (blue) shift spectrum is observed for positive (negative) EPC along the zigzag direction. Incorporating electric field effects in the EPC increases band gaps for both positive and negative EPC activities, resulting in shifted optical peaks along both directions.

Complete genome sequence of a novel lytic phage of Xanthomonas oryzae pv. oryzae, the bacterial leaf blight pathogen in rice.

Bacteriophage L522, which infects Xanthomonas oryzae pv. oryzae, was isolated from a paddy leaf sample collected in Long An province, Vietnam. The phage shows myovirus morphology based on transmission electron microscopy. It displays a latent period and burst size of approximately 3 h and 63 new virions per infected cell (PFU/infected cell), respectively. The genome of L522 is 44,497 bp in length, with 52% GC content. Of the 63 genes identified, functions were predicted for 26. No virulence or antibiotic-resistance genes were detected. The results of a BLASTn search showed similarity to a previously reported Xanthomonas phage, with 85% average nucleotide sequence identity and 87.15% query coverage. Thus, this L522 is a representative of a new species in the genus Xipdecavirus.

Sensitive CometChip assay for screening potentially carcinogenic DNA adducts by trapping DNA repair intermediates.

Genotoxicity testing is critical for predicting adverse effects of pharmaceutical, industrial, and environmental chemicals. The alkaline comet assay is an established method for detecting DNA strand breaks, however, the assay does not detect potentially carcinogenic bulky adducts that can arise when metabolic enzymes convert pro-carcinogens into a highly DNA reactive products. To overcome this, we use DNA synthesis inhibitors (hydroxyurea and 1-ß-d-arabinofuranosyl cytosine) to trap single strand breaks that are formed during nucleotide excision repair, which primarily removes bulky lesions. In this way, comet-undetectable bulky lesions are converted into comet-detectable single strand breaks. Moreover, we use HepaRG™ cells to recapitulate in vivo metabolic capacity, and leverage the CometChip platform (a higher throughput more sensitive comet assay) to create the 'HepaCometChip', enabling the detection of bulky genotoxic lesions that are missed by current genotoxicity screens. The HepaCometChip thus provides a broadly effective approach for detection of bulky DNA adducts.

In vivo measurements of interindividual differences in DNA glycosylases and APE1 activities.

The integrity of our DNA is challenged with at least 100,000 lesions per cell on a daily basis. Failure to repair DNA damage efficiently can lead to cancer, immunodeficiency, and neurodegenerative disease. Base excision repair (BER) recognizes and repairs minimally helix-distorting DNA base lesions induced by both endogenous and exogenous DNA damaging agents. Levels of BER-initiating DNA glycosylases can vary between individuals, suggesting that quantitating and understanding interindividual differences in DNA repair capacity (DRC) may enable us to predict and prevent disease in a personalized manner. However, population studies of BER capacity have been limited because most methods used to measure BER activity are cumbersome, time consuming and, for the most part, only allow for the analysis of one DNA glycosylase at a time. We have developed a fluorescence-based multiplex flow-cytometric host cell reactivation assay wherein the activity of several enzymes [four BER-initiating DNA glycosylases and the downstream processing apurinic/apyrimidinic endonuclease 1 (APE1)] can be tested simultaneously, at single-cell resolution, in vivo. Taking advantage of the transcriptional properties of several DNA lesions, we have engineered specific fluorescent reporter plasmids for quantitative measurements of 8-oxoguanine DNA glycosylase, alkyl-adenine DNA glycosylase, MutY DNA glycosylase, uracil DNA glycosylase, and APE1 activity. We have used these reporters to measure differences in BER capacity across a panel of cell lines collected from healthy individuals, and to generate mathematical models that predict cellular sensitivity to methylmethane sulfonate, H2O2, and 5-FU from DRC. Moreover, we demonstrate the suitability of these reporters to measure differences in DRC in multiple pathways using primary lymphocytes from two individuals.

ß12-Borophene becomes a semiconductor and semimetal via a perpendicular electric field and dilute charged impurity.

In this paper, the possible electronic phase transitions of ß12-borophene crystal are examined using a five-band tight-binding calculation. For different tight-binding models, the Green's function technique is employed for the electronic density of states (DOS). We focus on the modulation of the DOS around the Fermi level with a perpendicular electric field and the dilute charged impurity. The steps to incorporate the effects of external electric field and charged impurity are also detailed with the local Hamiltonian model and the Born approximation, respectively. Our calculations show that the inversion symmetric model is the proper model to discuss the metallic phase of the system, entailing different results compared to the homogeneous model. We find that the electric field opens a tunable band gap and a metal-to-p-doped semiconductor phase transition emerges at the strong perpendicular electric field. The influence of impurity scattering potential on the electronic phase of ß12-borophene is much larger than the impurity concentration, in which a metal-to-n-doped semiconductor (metal-to-semimetal) transition takes place at high scattering potentials for the homogeneous (inversion symmetric) model, whereas there is no transition when the impurity concentration is changed. Thereby, producing semimetallic/semiconducting properties by applying an appropriate external electric field and dilute charged impurities paves the way for the realization of ß12-borophene-based nano-optoelectronic devices.

Charged impurity-tuning of midgap states in biased Bernal bilayer black phosphorus: an anisotropic electronic phase transition.

In this paper, we analytically investigate the electronic density of states (DOS) of bilayer Bernal black phosphorus (BBP) in order to study the anisotropic electronic phase transition. We employ the Green's function approach, the Born approximation, and the tight-binding Hamiltonian model including ten intra-layer and four inter-layer hopping energies. BBP consisting of two coupled layers of black phosphorus is a suitable candidate for studying the layer-dependent electronic properties of few-layer black phosphorus. We examine the electronic properties of BBP under conditions in which only one layer and both layers are subjected to a dilute charged impurity and a perpendicular electric field. Our findings show that there is no phase transition when the impurity is doped on only one layer, whereas in the case of both layers, BBP suffers a phase transition from semiconductor to semimetal at strong impurity scattering potentials. Also, applying the electric field on one layer of BBP leads to an increase in the band gap, whereas in the case of both layers, the band gap decreases with the electric field and eventually, a phase transition appears at a bias voltage of more than 1.8 eV. Consequently, the band gap of BBP can be tuned by applying an electric field and a charged impurity, and thereby these findings provide insights for future experimental research on black phosphorus.

Interplay of orbital hopping and perpendicular magnetic field in anisotropic phase transitions for Bernal bilayer graphene and hexagonal boron-nitride.

We theoretically address the perpendicular magnetic field effects on the electronic phase of Bernal bilayer graphene and hexagonal boron-nitride (h-BN) taking into account the total and orbital-projected electronic bands using the tight-binding parameters in the Harrison model, followed by the Green's function method. First, we confirm that our model is computationally efficient and accurate for calculating the magneto-orbital electronic phase transition by reproducing the semimetallic and insulating treatments of pristine Bernal bilayer graphene and h-BN, respectively. In our model, the magnetic field couples only to the electron spin degrees of freedom (with the same contributions for spin-up and spin-down) due to the low dimension of the systems. Here, the main features of the phase transitions are characterized by the electronic density of states (DOS). We found that sp2-hybridization is destroyed when the systems are immersed in the magnetic field, leading to a phase transition to metal for both systems at strong magnetic fields. While there is no phase transition for bilayer graphene at weak magnetic fields, for the case of bilayer h-BN, an insulator to semiconductor phase transition can be viewed, making h-BN more applicable in industry. In bilayer graphene, the anisotropic phase transition appears as insulator-semiconductor, insulator-metal, and semimetal-metal for s-, {px + py}-, and pz-orbitals, respectively, whereas in the case of bilayer h-BN, one observes the same transitions for {s,pz}-orbitals but insulator-semiconductor for {px + py} orbitals. Generically, our findings highlight that the applied magnetic field manipulates the band structure of bilayer graphene and h-BN, and gives ideas to experimentalists for tuning the electro-optical properties of these materials.

Structural and electronic properties of a van der Waals heterostructure based on silicene and gallium selenide: effect of strain and electric field.

Combining van der Waals heterostructures by stacking different two-dimensional materials on top of each other layer-by-layer can enhance their desired properties and greatly extend the applications of the parent materials. In this work, by means of first principles calculations, we investigate systematically the structural and electronic properties of six different stacking configurations of a Si/GaSe heterostructure. The effect of biaxial strain and electric field on the electronic properties of the most energetically stable configuration of the Si/GaSe heterostructure has also been discussed. At the equilibrium state, the electronic properties of the Si/GaSe heterostructure in all its stacking configurations are well kept as compared with that of single layers owing to their weak van der Waals interactions. Interestingly, we find that a sizable band gap is opened at the Dirac K point of silicene in the Si/GaSe heterostructure, which could be further controlled by biaxial strain or electric field. These findings open up a possibility for designing silicene-based electronic devices, which exhibit a controllable band gap. Furthermore, the Si/GaSe heterostructure forms an n-type Schottky contact with a small Schottky barrier height of 0.23 eV. A transformation from the n-type Schottky contact to a p-type one, or from the Schottky contact to an ohmic contact may occur in the Si/GaSe heterostructure when strain or an electric field is applied.

Virulent bacteriophage of Edwardsiella ictaluri isolated from kidney and liver of striped catfish Pangasianodon hypophthalmus in Vietnam.

Striped catfish Pangasianodon hypophthalmus farmed in the Mekong Delta, Vietnam, represents an important contribution to Vietnamese aquaculture exports. However, these fish are affected by frequent disease outbreaks across the entire region. One of the most common infections involves white spots in the internal organs, caused by the bacterium Edwardsiella ictaluri. In this study, a virulent phage specific to E. ictaluri, designated MK7, was isolated from striped catfish kidney and liver samples and characterized. Morphological analysis indicates probable placement in the family Myoviridae with a 65 nm icosahedral head and a 147 %%CONV_ERR%% 19 nm tail. A double-stranded DNA genome of approximately 34 kb was predicted by restriction fragment analysis following digestion with SmaI. The adsorption affinity (ka) of the MK7 phage was estimated as 1.6 %%CONV_ERR%% 10-8 ml CFU-1 min-1, and according to a 1-step growth curve, its latent period and burst size were ~45 min and ~55 phage particles per infected host cell, respectively. Of the 17 bacterial strains tested, MK7 only infected E. ictaluri, although other species of Edwardsiella were not tested. E. ictaluri was also challenged in vitro, in both broth and water from a striped catfish pond and was inactivated by MK7 for 15 h in broth and 51 h in pond water. Thus, initial characterization of phage MK7 indicates its potential utility as a biotherapeutic agent against E. ictaluri infection in striped catfish. This is the first report of a lytic phage specific to an important striped catfish pathogen.

Protection of Penaeus monodon against white spot syndrome by continuous oral administration of a low concentration of Bacillus subtilis spores expressing the VP28 antigen.

In this study, Bacillus subtilis spores expressing a chimeric protein, CotB-VP28, were used as a probiotic vaccine to protect black tiger shrimps (Penaeus monodon) against white spot syndrome virus (WSSV) infection. Oral administration of pellets coated with CotB-VP28 spores (at ≥1 × 109  CFU per g pellet) to shrimps induced immune-relating phenoloxydase activity (PO) in shrimps after 14 days of feeding (prior challenge) and at day 3 post challenge (1·26 and 1·70 fold increase respectively). A 75% protection rate was obtained by continuous feeding of the spore-coated pellets at ≥1 × 109  CFU per g for 14 days prior to WSSV challenge and during all the postchallenge period. Even when the amount of CotB-VP28 spores in feed pellets was reduced down to ≥5 × 107  CFU per g and ≥1 × 106  CFU per g, relatively high protection rates of 70 and 67·5%, respectively, were still obtained. By contrast, feeding pellets without spores (untreated group) and with naked spores (PY79 group) at ≥1 × 109  CFU per g could not protect shrimps against WSSV. These data suggest that supplementation of CotB-VP28 spores at low dose of ≥1 × 106  CFU per g could be effective as a prophylactic treatment of WSS for black tiger shrimps. SIGNIFICANCE AND IMPACT OF THE STUDY: This study reports the protective efficacy of Bacillus subtilis CotB-VP28 spores on black tiger shrimps (Penaeus monodon) against white spot syndrome virus infection. Oral administration of pellets coated with CotB-VP28 spores (≥1 × 109  CFU per g) conferred 75% protection after white spot syndrome virus challenge. Even after reducing CotB-VP28 spores in feed pellets to ≥1 × 106  CFU per g, 67·5% protections was still obtained. These data indicate that supplementation of CotB-VP28 spores at a low dose of ≥1 × 106  CFU per g could be effective in prophylaxis against white spot syndrome in black tiger shrimps.

Biogas production from vietnamese animal manure, plant residues and organic waste: influence of biomass composition on methane yield.

Anaerobic digestion is an efficient and renewable energy technology that can produce biogas from a variety of biomasses such as animal manure, food waste and plant residues. In developing countries this technology is widely used for the production of biogas using local biomasses, but there is little information about the value of these biomasses for energy production. This study was therefore carried out with the objective of estimating the biogas production potential of typical Vietnamese biomasses such as animal manure, slaughterhouse waste and plant residues, and developing a model that relates methane (CH4) production to the chemical characteristics of the biomass. The biochemical methane potential (BMP) and biomass characteristics were measured. Results showed that piglet manure produced the highest CH4 yield of 443 normal litter (NL) CH4 kg(-1) volatile solids (VS) compared to 222 from cows, 177 from sows, 172 from rabbits, 169 from goats and 153 from buffaloes. Methane production from duckweed (Spirodela polyrrhiza) was higher than from lawn grass and water spinach at 340, 220, and 110.6 NL CH4 kg(-1) VS, respectively. The BMP experiment also demonstrated that the CH4 production was inhibited with chicken manure, slaughterhouse waste, cassava residue and shoe-making waste. Statistical analysis showed that lipid and lignin are the most significant predictors of BMP. The model was developed from knowledge that the BMP was related to biomass content of lipid, lignin and protein from manure and plant residues as a percentage of VS with coefficient of determination (R-square) at 0.95. This model was applied to calculate the CH4 yield for a household with 17 fattening pigs in the highlands and lowlands of northern Vietnam.

The trastuzumab and vinorelbine combination: an alternative to taxane-based chemotherapy for early-stage and locally advanced her2-positive breast cancer.

BACKGROUND: Anthracyclines and taxanes have historically constituted the backbone of chemotherapy regimens for patients with breast cancer positive for the human epidermal growth factor receptor 2 (her2). For a subset of patients who categorically refuse alopecia, or for those with a contraindication to those drugs, there is an urgent need to define alternative regimens. Here, we report our institutional experience with trastuzumab and vinorelbine (tv), a combination with good clinical activity and a good side effect profile for patients with her2-positive breast cancer. METHODS: In a retrospective analysis, outcomes data were extracted for patients receiving tv as their only chemotherapy in the non-metastatic setting at the Jewish General Hospital. For the most part, tv was administered weekly for 6 months, followed by trastuzumab for 6 months. RESULTS: The analysis identified 46 patients (mean age: 64 years) who received tv between 2003 and 2012 (n = 36 adjuvant, n = 10 neoadjuvant). Of the patients in the adjuvant group, 81% had stage i disease. In the neoadjuvant group, 3 patients experienced a complete pathologic response. Only 1 patient experienced local recurrence after a short course (3 months) of adjuvant tv. Overall survival and breast cancer-specific survival were 94% and 98% respectively at a median 5 years of follow-up. Febrile neutropenia-induced sepsis resulted in the death of 1 patient with significant medical comorbidities; 2 other patients died of comorbidities unrelated to their cancer or treatment. Grades 3 or 4 adverse events included neutropenia (23%), febrile neutropenia (10%), fatigue (2%), and anemia (2%). CONCLUSIONS: For patients with non-metastatic breast cancer refusing alopecia, or for patients who are not candidates for standard chemotherapy, tv is a reasonable alternative to standard adjuvant chemotherapy.

Hormonal manipulation with letrozole in the treatment of metastatic malignant pecoma.

Perivascular epithelioid cell tumours (pecomas) are rare mesenchymal tumours. Some have a benign course; others metastasize. Treatment of malignant pecomas is challenging, and little is known about treatment for patients with metastatic disease. Here, we report a case of metastatic malignant pecoma with estrogen and progesterone receptor expression that showed a favourable and sustained response to letrozole.

Nutlin-3 preferentially sensitises wild-type p53-expressing cancer cells to DR5-selective TRAIL over rhTRAIL.

BACKGROUND: Tumour cell-selective activation of apoptosis by recombinant human TNF-related apoptosis-inducing ligand (rhTRAIL) is enhanced through co-activation of p53 by chemotherapeutic drugs. The novel anticancer agent nutlin-3 provides a promising alternative for p53 activation by disrupting the interaction between p53 and its negative feedback regulator MDM2. METHODS: We examined whether nutlin-3 enhances apoptosis induction by rhTRAIL and the DR5-selective TRAIL variant D269H/E195R in wild-type p53-expressing ovarian, colon and lung cancer cell lines and in an ex vivo model of human ovarian cancer. RESULTS: Nutlin-3 enhanced p53, p21, MDM2 and DR5 surface expression. Although nutlin-3 did not induce apoptosis, it preferentially enhanced D269H/E195R-induced apoptosis over rhTRAIL. Combination treatment potentiated the cleavage of caspases 8, 9, 3 and PARP. P53 and MDM2 siRNA experiments showed that this enhanced apoptotic effect was mediated by wild-type p53. Indeed, nutlin-3 did not enhance rhTRAIL-induced apoptosis in OVCAR-3 cells harbouring mutant p53. Addition of the chemotherapeutic drug cisplatin to the combination further increased p53 and DR5 levels and rhTRAIL- and D269H/E195R-induced apoptosis. As a proof of concept, we show that the combination of D269H/E195R, nutlin-3 and cisplatin induced massive apoptosis in ex vivo tissue slices of primary human ovarian cancers. CONCLUSION: Nutlin-3 is a potent enhancer of D269H/E195R-induced apoptosis in wild-type p53-expressing cancer cells. Addition of DNA-damaging agents such as cisplatin further enhances DR5-mediated apoptosis.

Bacteriophage PVN06 protected catfish Pangasianodon hypophthalmus from Edwardsiella ictaluri infection.

Bacillary necrosis of pangasius (BNP) is a disease caused by Edwardsiella ictaluri bacteria in striped catfish Pangasianodon hypophthalmus that results in high mortality rates. To control this disease, bacteriophages have been considered as alternatives to antibiotics. In this study, we applied the lytic bacteriophage PVN06 in striped catfish fingerlings to prevent E. ictaluri infection. In an experimental trial, the phage was administered to fish by feeding phage-coated feed with doses of 7.17±0.09, 8.17±0.09 and 9.17±0.09 log PFU/g feed per day before bacterial infection. Fish were infected by bacteria once with concentrations ranging from 3.01 to 7.01 log CFU/ml tank water. A day after infection, phage treatment resumed at a rate of once per day until the end of the trial. The results of the trial show that bacterial infection caused typical symptoms of BNP in fish with the cumulative fish death rate of 36.7±2.9 to 75.0±5.0%, depending on the bacterial concentration used for infection. Phage treatment with 9.17±0.09 log PFU/g significantly reduced the mortality rate, while treatments with 8.17±0.09 and 7.17±0.09 log PFU/g did not. This phage dose resulted in a 61.7-fold reduction in the toxicity of the bacterial pathogen and the survival rate of 15-23.3% in fish. Our study has demonstrated that the bacteriophage PVN06 protected striped catfish from BNP.

[Respiratory complications of sickle cell anemia in children: the acute chest syndrome]. / Les complications respiratoires de la drépanocytose chez les enfants: le syndrome thoracique aigu.

The acute chest syndrome (ACS) is one of the most frequent complications of sickle cell disease. It affects mostly young children and counts for one quarter of mortality in the young sickle cell disease (SCD) population. This retrospective study evaluates the impact of ACS among hospitalizations for other complications of SCD in patients at the University Childrens' Hospital Reine Fabiola (Brussels, Belgium) in order to isolate clinical conditions associated with a high risk of ACS development. The medical records of all SCD patients aged up to 18 years admitted for all SCD related acute complications over a period of 13 month have been reviewed. Two patient groups have been formed based on the presence of an ACS within the study period. Epidemiologic data, medical history, the clinical presentation at admission but also blood counts in steady state, at admission and along the hospital stay were compared for a total of 96 hospital stays. There is no difference for age or hemoglobin phenotype between the two major patient groups. Male sex and having had a previous ACS episode in the past were significantly more important in the group of patients hospitalized for ACS. Thoracic pain in an SCD patient who doesn't show typical ACS symptoms should be interpreted as a risk factor for ACS. In conclusion, male sex, medical history of at least one ACS and thoracic pain at hospital admission are associated with high risk of developing ACS.

Bacterial chemotaxis in static gradients quantified in a biopolymer membrane-integrated microfluidic platform.

Chemotaxis is a fundamental bacterial response mechanism to changes in chemical gradients of specific molecules known as chemoattractant or chemorepellent. The advancement of biological platforms for bacterial chemotaxis research is of significant interest for a wide range of biological and environmental studies. Many microfluidic devices have been developed for its study, but challenges still remain that can obscure analysis. For example, cell migration can be compromised by flow-induced shear stress, and bacterial motility can be impaired by nonspecific cell adhesion to microchannels. Also, devices can be complicated, expensive, and hard to assemble. We address these issues with a three-channel microfluidic platform integrated with natural biopolymer membranes that are assembled in situ. This provides several unique attributes. First, a static, steady and robust chemoattractant gradient was generated and maintained. Second, because the assembly incorporates assembly pillars, the assembled membrane arrays connecting nearby pillars can be created longer than the viewing window, enabling a wide 2D area for study. Third, the in situ assembled biopolymer membranes minimize pressure and/or chemiosmotic gradients that could induce flow and obscure chemotaxis study. Finally, nonspecific cell adhesion is avoided by priming the polydimethylsiloxane (PDMS) microchannel surfaces with Pluronic F-127. We demonstrated chemotactic migration of Escherichia coli as well as Pseudomonas aeruginosa under well-controlled easy-to-assemble glucose gradients. We characterized motility using the chemotaxis partition coefficient (CPC) and chemotaxis migration coefficient (CMC) and found our results consistent with other reports. Further, random walk trajectories of individual cells in simple bright field images were conveniently tracked and presented in rose plots. Velocities were calculated, again in agreement with previous literature. We believe the biopolymer membrane-integrated platform represents a facile and convenient system for robust quantitative assessment of cellular motility in response to various chemical cues.

Botrytis pseudocinerea, a new cryptic species causing gray mold in French vineyards in sympatry with Botrytis cinerea.

Botrytis cinerea is a major crop pathogen infesting >220 hosts worldwide. A cryptic species has been identified in some French populations but the new species, B. pseudocinerea, has not been fully delimited and established. The aim of this study was to distinguish between the two species, using phylogenetic, biological, morphological, and ecological criteria. Multiple gene genealogies confirmed that the two species belonged to different, well-supported phylogenetic clades. None of the morphological criteria tested (spore size, germination rate, or mycelial growth) was able to discriminate between these two species. Sexual crosses between individuals from the same species and different species were carried out. Only crosses between individuals from the same species were successful. Moreover, population genetics analysis revealed a high level of diversity within each species and a lack of gene flow between them. Finally, a population survey over time showed that B. cinerea was the predominant species but that B. pseudocinerea was more abundant in spring, on floral debris. This observation could not be explained by temperature adaptation in tests carried out in vitro or by aggressiveness on tomato or bean leaves. This study clearly establishes that B. cinerea and B. pseudocinerea constitute a complex of two cryptic species living in sympatry on several hosts, including grapevine and blackberry. We propose several biological or molecular tools for unambiguous differentiation between the two species. B. pseudocinerea probably makes a negligible contribution to gray mold epidemics on grapevine. This new species has been deposited in the MycoBank international database.

[Thrombin generation test: establishment of reference values according to age and tissue factor concentration is essential before implementation into the laboratory]. / Test de génération de thrombine: importance d'établir les valeurs de référence en fonction de l'âge et des concentrations en facteur tissulaire avant l'implémentation au laboratoire.

The calibrated and automated thrombinography (CAT) developed by H.C. Hemker is a simple and reproducible technique that can be potentially used in coagulation laboratories. This test is able to record the complete thrombin generation in vitro, giving an interesting approach in the evaluation of the haemostatic potential at the individual level. We aimed to implement this test in our laboratory to follow patients with haemorrhagic or thrombotic pathologies. Haemorrhagic and thrombotic disorders are incompletely explored by the coagulation tests used presently in routine labs. These tests don't indeed reflect the real haemostatic phenotype of the patient neither the individual response to haemostatic treatments. Furthermore, they don't have any predictive value for the occurrence of haemorrhage and/or thrombosis. We report here reference values we established in a population of children and adults in pre-analytical conditions easily applicable in coagulation labs. Platelet poor plasma is prepared by a double centrifugation and analyzed immediately or frozen at -80 degrees C for delayed analysis.

CometChip analysis of human primary lymphocytes enables quantification of inter-individual differences in the kinetics of repair of oxidative DNA damage.

Although DNA repair is known to impact susceptibility to cancer and other diseases, relatively few population studies have been performed to evaluate DNA repair kinetics in people due to the difficulty of assessing DNA repair in a high-throughput manner. Here we use the CometChip, a high-throughput comet assay, to explore inter-individual variation in repair of oxidative damage to DNA, a known risk factor for aging, cancer and other diseases. DNA repair capacity after H2O2-induced DNA oxidation damage was quantified in peripheral blood mononuclear cells (PBMCs). For 10 individuals, blood was drawn at several times over the course of 4-6 weeks. In addition, blood was drawn once from each of 56 individuals. DNA damage levels were quantified prior to exposure to H2O2 and at 0, 15, 30, 60, and 120-min post exposure. We found that there is significant variability in DNA repair efficiency among individuals. When subdivided into quartiles by DNA repair efficiency, we found that the average t1/2 is 81 min for the slowest group and 24 min for the fastest group. This work shows that the CometChip can be used to uncover significant differences in repair kinetics among people, pointing to its utility in future epidemiological and clinical studies.