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Impaired linear growth has been reported in patients treated during childhood with allogeneic stem cell transplantation and fractionated total body irradiation (fTBI). The objective of this study was to determine the final height and body mass index (BMI) achieved. Forty-nine patients with leukemia were included and surveyed for more than 5 years. Median age at follow-up was 24.3 years (range, 18.9-35.8) and median follow-up time from allograft was 14.4 years (range, 4.5-21.9). Mean height standard deviation score (s.d.s.) at final examination (-1.1 ± 1.3,) was significantly lower than at fTBI (0.3 ± 1.2; P = .001). Final height s.d.s. was significantly correlated with age at diagnosis, age at fTBI, and target height (P = .001; P < .001; P < .001, respectively). Final height was significantly lower in children transplanted before age 5 (P = .006). Growth hormone treatment (n = 6) had only a modest effect on growth velocity. Mean BMI at follow-up was normal at 19.6 kg/m(2) for boys and 21.2 for girls, but with a significant decrease since allograft only for boys (-1.2 ± 1.5 s.d.s.) (P = .003). In conclusion, final height is decreased; BMI is normal but decreased from fTBI in boys.

Electronic carriers in graphene show a high carrier mobility at room temperature. Thus, this system is widely viewed as a potential future charge-based high-speed electronic material to complement-or replace-silicon. At the same time, the spin properties of graphene have suggested improved capability for spin-based electronics or spintronics and spin-based quantum computing. As a result, the detection, characterization and transport of spin have become topics of interest in graphene. Here we report a microwave photo-excited transport study of monolayer and trilayer graphene that reveals an unexpectedly strong microwave-induced electrical response and dual microwave-induced resonances in the dc resistance. The results suggest the resistive detection of spin resonance, and provide a measurement of the g-factor, the spin relaxation time and the sub-lattice degeneracy splitting at zero magnetic field.

After the pioneering investigations into graphene-based electronics at Georgia Tech, great strides have been made developing epitaxial graphene on silicon carbide (EG) as a new electronic material. EG has not only demonstrated its potential for large scale applications, it also has become an important material for fundamental two-dimensional electron gas physics. It was long known that graphene mono and multilayers grow on SiC crystals at high temperatures in ultrahigh vacuum. At these temperatures, silicon sublimes from the surface and the carbon rich surface layer transforms to graphene. However the quality of the graphene produced in ultrahigh vacuum is poor due to the high sublimation rates at relatively low temperatures. The Georgia Tech team developed growth methods involving encapsulating the SiC crystals in graphite enclosures, thereby sequestering the evaporated silicon and bringing growth process closer to equilibrium. In this confinement controlled sublimation (CCS) process, very high-quality graphene is grown on both polar faces of the SiC crystals. Since 2003, over 50 publications used CCS grown graphene, where it is known as the "furnace grown" graphene. Graphene multilayers grown on the carbon-terminated face of SiC, using the CCS method, were shown to consist of decoupled high mobility graphene layers. The CCS method is now applied on structured silicon carbide surfaces to produce high mobility nano-patterned graphene structures thereby demonstrating that EG is a viable contender for next-generation electronics. Here we present for the first time the CCS method that outperforms other epitaxial graphene production methods.

Studies of second malignant neoplasms (SMNs) in childhood are generally conducted in old cohorts. The aim of this study was to determine the actual incidence of all SMNs in a recent cohort. The authors studied a cohort of 2907 children included in the population-based Childhood Cancer Registry of the Rhône-Alpes Region for a first cancer diagnosed between 1987 and 2004. Total follow-up was 22,722 person-years, with a median follow-up of 9.8 years (range, 00.0-22.8 years). Fifty-four SMNs were reported in 52 patients. Overall median latency was 5.9 years. Cumulative incidence rates were 2.2% at 10 years and 3.9% at 15, with an overall standardized incidence ratio (SIR) of 13.9 (95% confidence interval [CI], 10.4-18.3) and absolute excess risk of 2.2. The SMNs were 12 thyroid carcinomas (SIR 57.1); 9 bone tumors (SIR 32.0); 8 leukemias (SIR 11.9); 5 lymphomas, all related to Epstein-Barr virus following allograft, (SIR 6.7); 5 CNS tumors (SIR 10.5); 4 soft tissue sarcomas (SIR 17.4); 4 carcinomas (no breast cancer); and 7 other cancers. Twelve SMNs appeared after total body irradiation, 16 after focal radiotherapy, and 8 leukemias after chemotherapy. The risk of secondary cancer was highest after retinoblastomas (SIR 41.8), Hodgkin lymphomas (SIR 20.8), leukemias (SIR 18.4), soft tissue sarcomas, CNS tumors, and bone tumors. These recent cohort findings show, on one hand, a high incidence of SMNs but do not capture breast cancers because of the relatively short follow-up and, on the other hand, a different distribution of first and second cancers.

Background: Congenital acute leukemia is a rare event, presenting usually as an aggressive disease with a poor prognosis. A differential diagnosis is the transient myeloproliferative disorder observed in Down syndrome. We describe the case of an apparently healthy newborn male child presenting with normal peripheral blood (PB) counts but with a blast population on differentials. The child's condition and the blast population remained unchanged during the first year of life., Methods: Bone marrow and PB were morphologically analyzed. Multiparametric flow cytometry was performed at the time of diagnosis and repeated at 1 year. These studies were completed by cytogenetic and molecular analyses., Results: Bone marrow contained 40% of undifferentiated blasts. Multiparametric flow cytometry showed low expression of CD38, HLA-DR, and CD33 markers. All other markers were negative. Constitutional and blast cell karyotypes were normal. Fluorescence in situ hybridization analysis showed no rearrangement. Molecular studies were negative. The blast percentage remained stable during several months. After 1 year, the PB counts showed thrombocytopenia, with an increase of blast cells exhibiting the same phenotype. Clinically, an enlarged spleen was found. The child did not respond to chemotherapy and only partially to gemtuzumab ozogamicin. A cord blood cell transplantation was finally performed. With a follow-up of 12 months, the child is doing well., Conclusions: To our knowledge, this is the first case of congenital acute leukemia with initially indolent course in a newborn without Down syndrome. This observation emphasizes the importance of a careful follow-up., (Copyright © 2010 International Clinical Cytometry Society.)

Graphene's extraordinary physical properties and its planar geometry make it an ideal candidate for a wide array of applications, many of which require controlled chemical modification and the spatial organization of molecules on its surface. In particular, the ability to functionalize and micropattern graphene with proteins is relevant to bioscience applications such as biomolecular sensors, single-cell sensors, and tissue engineering. We report a general strategy for the noncovalent chemical modification of epitaxial graphene for protein immobilization and micropatterning. We show that bifunctional molecule pyrenebutanoic acid-succinimidyl ester (PYR-NHS), composed of the hydrophobic pyrene and the reactive succinimide ester group, binds to graphene noncovalently but irreversibly. We investigate whether the chemical treatment perturbs the electronic band structure of graphene using X-ray photoemission (XPS) and Raman spectroscopy. Our results show that the sp(2) hybridization remains intact and that the π band maintains its characteristic Lorentzian shape in the Raman spectra. The modified graphene surfaces, which bind specifically to amines in proteins, are micropatterned with arrays of fluorescently labeled proteins that are relevant to glucose sensors (glucose oxidase) and cell sensor and tissue engineering applications (laminin).

We report the effect of electrochemical oxidation in nitric acid on the electronic properties of epitaxial graphene (EG) grown on silicon carbide substrates; we demonstrate the availability of an additional reaction channel in EG, which is not present in graphite but which facilitates the introduction of the reaction medium into the graphene galleries during electro-oxidation. The device performance of the chemically processed graphene was studied by patterning the EG wafers with two geometrically identical macroscopic channels; the electro-oxidized channel showed a logarithmic increase of resistance with decreasing temperature, which is ascribed to the scattering of charge carriers in a two-dimensional electronic gas, rather than the presence of an energy gap at the Fermi level. Field-effect transistors were fabricated on the electro-oxidized and pristine graphene channels using single-walled carbon nanotube thin film top gate electrodes, thereby allowing the study of the effect of oxidative chemistry on the transistor performance of EG. The electro-oxidized channel showed higher values for the on-off ratio and the mobility of the graphene field-effect transistor, which we ascribe to the availability of high-quality internal graphene layers after electro-oxidation of the more defective top layers. Thus, the present oxidative process provides a clear contrast with previously demonstrated covalent chemistry in which sp(3) hybridized carbon atoms are introduced into the graphitic transport layer of the lattice by carbon-carbon bond formation, thereby opening an energy gap.

In order to engineer a band gap into graphene, covalent bond-forming reactions can be used to change the hybridization of the graphitic atoms from sp(2) to sp(3), thereby modifying the conjugation length of the delocalized carbon lattice; similar side-wall chemistry has been shown to introduce a band gap into metallic single-walled carbon nanotubes. Here we demonstrate that the application of such covalent bond-forming chemistry modifies the periodicity of the graphene network thereby introducing a band gap (∼0.4 eV), which is observable in the angle-resolved photoelectron spectroscopy of aryl-functionalized graphene. We further show that the chemically-induced changes can be detected by Raman spectroscopy; the in-plane vibrations of the conjugated π-bonds exhibit characteristic Raman spectra and we find that the changes in D, G, and 2D-bands as a result of chemical functionalization of the graphene basal plane are quite distinct from that due to localized, physical defects in sp(2)-conjugated carbon.

The reduced form of graphene oxide (GO) is an attractive alternative to graphene for producing large-scale flexible conductors and for creating devices that require an electronic gap. We report on a means to tune the topographical and electrical properties of reduced GO (rGO) with nanoscopic resolution by local thermal reduction of GO with a heated atomic force microscope tip. The rGO regions are up to four orders of magnitude more conductive than pristine GO. No sign of tip wear or sample tearing was observed. Variably conductive nanoribbons with dimensions down to 12 nanometers could be produced in oxidized epitaxial graphene films in a single step that is clean, rapid, and reliable.

Background: beta-thalassemia is a rare disease in France, encountered mainly in patients originating from Italy and North Africa. In the setting of the recent French plan for rare diseases, a National Registry for thalassemia has been developed since 2005. Epidemiological and clinical data have been collected on living patients with beta-thalassemia major or intermedia, including those who underwent hematopoietic stem cell transplantation., Design and Methods: A standardized questionnaire was sent to clinicians throughout the national professional networks involved in the management of thalassemic patients and data were updated every 18 months. A cross-sectional study was performed in February 2009., Results: Data on 378 patients (267 with thalassemia major) with a median age of 20 were recorded. Hematopoietic stem cell transplantation was performed in 52 patients. Stature, rates of parenthood, splenectomy, and cholecystectomy were no different between non-transplanted thalassemia major and thalassemia intermedia patients, after adjustment for age. Among the 215 non-transplanted thalassemia major patients, the median serum ferritin level was 1240 ng/mL and the rates of iron-related complications were 10%, 6%, 10% and 48% for cardiac failure, diabetes, hypothyroidism, and hypogonadism, respectively. From 2005 to 2008, a dramatic switch in chelation treatment, from deferoxamine to deferasirox, was observed., Conclusions: The rates of complications of iron overload in French thalassemia major patients appeared similar to those reported in other developed countries in which this condition is not endemic. There were no significant differences in height and parenthood rates between patients with the major and the intermedia forms of the disease, underlining the progress in clinical care. Future developments will focus on mortality and morbidity under oral chelation treatment.

We report generation of ballistic electric currents in unbiased epitaxial graphene at 300 K via quantum interference between phase-controlled cross-polarized fundamental and second harmonic 220 fs pulses. The transient currents are detected via the emitted terahertz radiation. Because of graphene's special structure symmetry, the injected current direction can be well controlled by the polarization of the pump beam in epitaxial graphene. This all optical injection of current provides not only a noncontact way of injecting directional current in graphene but also new insight into optical and transport process in epitaxial graphene.

The substrate-induced charge-density profile in carbon face epitaxial graphene is determined using nondegenerate ultrafast midinfrared pump-probe spectroscopy. Distinct zero crossings in the differential transmission spectra are used to identify the Fermi levels of layers within the multilayer stack. Probing within the transmission window of the SiC substrate, we find the Fermi levels of the first four heavily doped layers to be, respectively, 360, 215, 140, and 93 meV above the Dirac point. The charge screening length is determined to be one graphene layer, in good agreement with theoretical predictions.

Purpose: At the present time, the standard approach for renal cancer in children is open surgery, and the role of laparoscopic approach remains to be defined. We report our preliminary experience in the treatment by laparoscopic radical nephrectomy (LRN) for unilateral renal cancer in children., Methods: Five children, whose mean age was 4 years old, were operated for unilateral renal malignant tumors by laparoscopic approach in our unit from October 2005 to June 2007. Four cases were suspected of Wilms tumors and one of them presented bilateral lung metastases. They were preoperatively treated with chemotherapy according to the International Society of Pediatric Oncology 2001 protocol: vincristine and actinomicyn D for 4 weeks. The fifth case was a 10-year-old child, treated 8 years before with chemotherapy for a cerebellar vermis medulloblastoma history. A percutaneous biopsy was performed preoperatively and the histology showed a juvenile renal-cell carcinoma. All cases subsequently underwent LRN. Four trocars were used in each case and the tumors were placed in a bag before being extracted intact without morcellation through a low suprapubic incision., Results: All tumors and lymph node samples were removed completely by laparoscopy without rupture. No conversion to laparotomy was necessary and there was neither intraoperative bleeding nor complications. The mean operative time was 90 minutes (60 to 117 min). Postoperatively, 1 child presented an intestinal perforation and suture closure was performed by laparoscopy on the third postoperative day; the discharge was after 10 days, and the others were discharged after 2 or 3 days. In all cases, the resection was microscopically complete. The histology was 3 unilateral Wilms tumor, 1 clear-cell sarcoma and 1 juvenile renal-cell carcinoma with t(X;17). No lymph node was positive for the tumors. None of these patients presented evidence of tumoral recurrences, port-site implantation or short-term complications at a mean of 18 months of follow-up (range: 12 to 32 mo)., Conclusions: LRN for renal cancer in children is feasible after preoperative chemotherapy, with the same oncologic strategies as open surgery. A long follow-up and more cases are necessary to evaluate and compare the results of laparoscopic approach with the open procedures.

The addition of nitrophenyl groups to the surface of few-layer epitaxial graphene (EG) by the formation of covalent carbon-carbon bonds changed the electronic structure and transport properties of the EG from near-metallic to semiconducting.

We investigate the ultrafast relaxation dynamics of hot Dirac fermionic quasiparticles in multilayer epitaxial graphene using ultrafast optical differential transmission spectroscopy. We observe differential transmission spectra which are well described by interband transitions with no electron-hole interaction. Following the initial thermalization and emission of high-energy phonons, the electron cooling is determined by electron-acoustic phonon scattering, found to occur on the time scale of 1 ps for highly doped layers, and 4-11 ps in undoped layers. The spectra also provide strong evidence for the multilayer structure and doping profile of thermally grown epitaxial graphene on SiC.

We propose a mechanism for the quenching of the Shubnikov-de Haas oscillations and the quantum Hall effect observed in epitaxial graphene. Experimental data show that the scattering time of the conduction electron is magnetic field dependent and of the order of the cyclotron orbit period, i.e., it can be much smaller than the zero field scattering time. Our scenario involves the extraordinary graphene n=0 Landau level of the uncharged layers which is pinned at the Fermi level. We find that the coupling between this n=0 Landau level and the conducting states of the doped plane leads to a scattering mechanism having the right magnitude to explain the experimental data.

Graphene-oxide (GO) flakes have been deposited to bridge the gap between two epitaxial-graphene electrodes to produce all-graphene devices. Electrical measurements indicate the presence of Schottky barriers at the graphene/graphene-oxide junctions, as a consequence of the band gap in GO. The barrier height is found to be about 0.7 eV, and is reduced after annealing at 180 degrees C, implying that the gap can be tuned by changing the degree of oxidation. A lower limit of the GO mobility was found to be 850 cm2/V s, rivaling silicon. In situ local oxidation of patterned epitaxial graphene has been achieved.

Natural killer (NK) cells have been originally defined by their "naturally occurring" effector function. However, only a fraction of human NK cells is reactive toward a panel of prototypical tumor cell targets in vitro, both for the production of interferon-gamma (IFN-gamma) and for their cytotoxic response. In patients with IL12RB1 mutations that lead to a complete IL-12Rbeta1 deficiency, the size of this naturally reactive NK cell subset is diminished, in particular for the IFN-gamma production. Similar data were obtained from a patient with a complete deficit in IL-12p40. In addition, the size of the subset of effector memory T cells expressing CD56 was severely decreased in IL-12Rbeta1- and IL-12p40-deficient patients. Human NK cells thus require in vivo priming with IL-12/23 to acquire their full spectrum of functional reactivity, while T cells are dependent upon IL-12/23 signals for the differentiation and/or the maintenance of CD56(+) effector memory T cells. The susceptibility of IL-12/23 axis-deficient patients to Mycobacterium and Salmonella infections in combination with the absence of mycobacteriosis or salmonellosis in the rare cases of human NK cell deficiencies point to a role for CD56(+) T cells in the control of these infections in humans.

Purpose: To identify prognostic factors and to evaluate the outcome of children with acute lymphoblastic leukemia (ALL) failure after induction therapy., Patients and Methods: Between June 1993 and December 1999, 1,395 leukemic children were included in the French Acute Lymphoblastic Leukemia 93 study., Results: Fifty-three patients (3.8%) had a leukemic induction failure (LIF) after three- or four-drug induction therapy. In univariate analysis, high WBC count (P = .001), mediastinal mass (P = .017), T-cell phenotype (T-ALL; P = .001), t(9;22) translocation (P = .001), and a slow early response (at day 8 and/or on day 21, P = .001) were predictive of LIF. The following three prognostic groups for LIF were identified by multivariate analysis: a low-risk group with B-cell progenitor (BCP) ALL without t(9;22) (odds ratio [OR] = 1), an intermediate-risk group with T-ALL and a mediastinal mass (OR = 7.4, P < .0001), and a high-risk group with BCP-ALL and t(9;22) or T-ALL without a mediastinal mass (OR = 28.4, P < .0001). Complete remission (CR) was subsequently obtained in 43 patients (81%). The 5-year overall survival (OS) rate of the 53 patients was 30% +/- 6%. The 5-year OS rate among allogeneic graft recipients, autologous graft recipients, and after chemotherapy were 30.4% +/- 9.6% (50% +/- 26% after genoidentical transplantation), 50% +/- 17.7%, and 41.7% +/- 14.2%, respectively (P = .18). Fourteen patients (26%) were still in first CR after a median of 83 months (range, 53 to 117 months)., Conclusion: Three risk categories for LIF in children with ALL were identified. Approximately one third of patients with LIF can be successfully treated with salvage therapy overall. Subsequent CR after LIF is mandatory for cure.

Two new fetal hemoglobin (Hb F) variants affecting the (G)gamma chain are reported: Hb F-Saint-Etienne [G gamma 79(EF3)Asp-->His] and Hb F-Lyon [G gamma 97(FG4)His-->Arg]. These new Hb variants were found during a neonatal screening for hemoglobinopathies but characterized a few months later by our reference laboratory. The corresponding mutations are located on the external part of the Hb molecule and seem to be clinically silent.

The aim of this study was to describe the overall survival after childhood cancer in France using follow-up data from regional population-based registries. The survival of children (aged under 15 years) diagnosed with a cancer during 1990-1999 was analysed. For all cancers, the survivals were, respectively, 90.3% [89.4-91.3] at 1-year, 75.2% [73.8-76.6] at 5 years and 72.2% [70.7-73.7] at 10 years. During the 1990s, the average improvement in the 5-year survival was +1.2% per year. Adjusted for gender, age, area of residence and stage, children with cancer diagnosed between 1995 and 1999 had a 0.80 reduced risk of dying compared with those whose cancer had been diagnosed between 1990 and 1994. The increase of survival at the population level reflects a global improvement in childhood cancer care. The Paediatric Registries, in association with the French Society of Childhood Cancer, are now collecting data to quantify on a national basis the other events, at least relapse and second cancers.

Background: Extracorporeal photochemotherapy (ECP) gives positive results in the management of graft-versus-host disease (GVHD), but in children, specific difficulties can outweigh this benefit. These difficulties must be taken into consideration when establishing a standardized reproducible procedure for implementation under a quality management plan., Study Design and Methods: Twenty-seven children underwent ECP for severe acute GVHD (aGVHD) or chronic GVHD (cGVHD) after allogeneic marrow transplantation. Data were collected prospectively, with particular emphasis placed on technical, biologic, immunologic, clinical, and long-term follow-up issues., Results: The 27 children underwent a total of 750 sessions. Mononuclear cells were collected on a commercially available apheresis system (COBE Spectra, Gambro BCT). Overall survival was 73 percent, and ECP led to significant improvement in 21 of the 27 patients (11 with complete response and 10 with partial response, i.e., >50% of organ involvement). Tolerance was good overall, the main limiting factors being vascular access and the psychological impact of repeated apheresis procedures. Children weighing less than 25 kg were not more susceptible to side effects., Conclusion: A specifically pediatric-dedicated and -experienced team faces only limited difficulties when treating children with GVHD by ECP. Overall, ECP is efficient and well tolerated. Our experience was therefore pooled together with available pediatric data to establish clinical practice guidelines. These guidelines consider ECP as a first-line therapy in Grade IV aGVHD (in association with conventional pharmacologic approaches) and limited cGVHD and as a second-line therapy in steroid-resistant Grades II to III aGVHD and extensive cGVHD.

Transport in ultrathin graphite grown on silicon carbide is dominated by the electron-doped epitaxial layer at the interface. Weak antilocalization in 2D samples manifests itself as a broad cusplike depression in the longitudinal resistance for magnetic fields 10 mT

Background: Chronic myelogenous leukemia (CML) is a rare disease in children and only few data are available concerning the results of interferon based therapy in this age group. Before the imatinib mesylate era, a prospective phase II trial was conducted to assess the efficacy and tolerance of a combination of interferon-alpha 2b (IFN) and cytarabine in children with CML in first chronic phase without a suitable HLA-identical donor., Procedure: Fourteen consecutive children were recruited from 12 pediatric centers. Children received daily IFN (5 million U/m2) and subcutaneous cytarabine (20 mg/m2) for 10 days every month., Results: The median duration of follow-up is 13 months (range 2-32 months). Seven children achieved a complete hematologic response after a median time of treatment of 3 months (range 1 week-4 months). Three children were not evaluable for the cytogenetic response. A major cytogenetic response was achieved in seven patients (including complete cytogenetic response in two patient) within 12 months. The median time to major cytogenetic response was 7 months (range 3-12 months). Thirteen patients discontinued the treatment protocol after a median time of 11 months. Probability of progression free survival at 11 months was 83% (95% CI, 61%-100%). Grade 3 and 4 toxicity was observed in eight patients. The most frequently reported drug-related events were fever, mucositis, neutropenia, and thrombocytopenia., Conclusions: The combination of IFN and cytarabine provides hematologic and cytogenetic responses in children and adolescents with CML. In the imatinib mesylate era, the role of this combination as second line therapy in children with CML remains to be determined., (Copyright (c) 2005 Wiley-Liss, Inc.)

Ultrathin epitaxial graphite was grown on single-crystal silicon carbide by vacuum graphitization. The material can be patterned using standard nanolithography methods. The transport properties, which are closely related to those of carbon nanotubes, are dominated by the single epitaxial graphene layer at the silicon carbide interface and reveal the Dirac nature of the charge carriers. Patterned structures show quantum confinement of electrons and phase coherence lengths beyond 1 micrometer at 4 kelvin, with mobilities exceeding 2.5 square meters per volt-second. All-graphene electronically coherent devices and device architectures are envisaged.

Direct sequencing of the coding region of factor VIII (F8) gene was used to determine the mutations responsible for severe haemophilia A (FVIII<1%) in 128 unrelated haemophiliacs A, negative for intron 22 and intron 1 inversions. A mutation was found in 122/128 patients (95%). Ninety-six distinct mutations were identified in this cohort, 62 of these are novel. They consisted of deletions (7 large and 24 small deletions), insertions (n = 9), associations of insertion/deletion (n = 2), association of deletion/substitution (n = 1), and single nucleotide substitutions (53 point mutations consisting of 31 missense, 20 nonsense, and 2 splicing mutations). Twenty-two patients had developed inhibitors, and among this subgroup 3 large deletions, 6 frameshift, 9 nonsense and 4 missense mutations were detected. For 6 patients, among which one developed an anti-FVIII inhibitor, no mutations were detected in the coding and splicing regions of factor VIII gene. Different approaches of molecular modelling were performed in addition to familial linkage analysis to determine the pathophysiological responsibility of these novel missense mutations.

We reviewed 64 pregnancies in 26 women with Diamond-Blackfan anemia (DBA) included in the French and German DBA registries. Complications were seen in 42 pregnancies (66%) and included abortion, pre-eclampsia, in utero fetal death, intrauterine growth retardation, retroplacental hematoma, pre-term delivery and fetal malformations. Of the 34 children (53%) born alive, 13 had DBA. No correlations were found between pregnancy outcome and features of either maternal or child DBA. Pregnancies in DBA-affected women are at high risk, especially for complications likely to be of vascular-placental origin. Careful monitoring with prevention of severe anemia and early introduction of aspirin is suggested.

The formation of carbon nanotubes in a pure carbon arc in a helium atmosphere is found to involve liquid carbon. Electron microscopy shows a viscous liquid-like amorphous carbon layer covering the surfaces of nanotube-containing millimeter-sized columnar structures from which the cathode deposit is composed. Regularly spaced, submicrometer-sized spherical beads of amorphous carbon are often found on the nanotubes at the surfaces of these columns. Apparently, at the anode, liquid-carbon drops form, which acquire a carbon-glass surface due to rapid evaporative cooling. Nanotubes crystallize inside the supercooled, glass-coated liquid-carbon drops. The carbon-glass layer ultimately coats and beads on the nanotubes near the surface.

Background: Cancer is the second most important cause of death for children aged less than 15 years in France, unintentional injuries being the leading cause. The aim of the present study was to estimate the incidence of childhood cancer from six Childhood Cancer Registries covering 32% of France., Procedure: Incident cancer cases diagnosed between 1990 and 1999 in children (0-14 years) resident in the administrative areas covered by each Registry were included. Annual age-standardized rates (ASRs) were adjusted by the world population. The estimated annual percent change (EAPC) was used to measure trend towards changes in the annual age-standardized incidence rate., Results: With 4234 registered cases, the ASRs per million children were 137.5 for all cancers combined, 42.3 for leukemia, 29.1 for central-nervous-system tumors, 15.6 for lymphomas, 14.1 for sympathetic-nervous-system tumors, and 9.1 for renal tumors. The ASR of all cancers combined was slightly higher in males (145.8 per million children) than in females (128.7 per million children) with an M/F ratio of 1.2. No significant incidence trend was observed, with an EAPC of +0.2% [IC 95% (-2.5; +3.0); P = 0.89]., Conclusions: The estimated incidence rates are similar to those reported in previous studies in European and North American countries. These results will contribute to the development of National Registration of Childhood Cancer in France and support the national research program on childhood cancer., (2004 Wiley-Liss, Inc.)

The electrical transport in multiwalled carbon nanotubes is shown to be ballistic at room temperature with mean free paths on the order of tens of microns. The measurements are performed both in air and in the transmission electron microscope by contacting the free end of a nanotube pointing out of a fiber to a liquid metal and measuring the dependence of the nanotube resistance between the contacts. For a specific representative nanotube the resistance per unit length is found to be Rt = 31 +/- 61 omega/micron and the contact resistance with the liquid metal, Rc = 165 +/- 55 omega microns, corresponding to a mean free path l = 200 microns. Current-to-voltage characteristics are in accord with the electronic structure. The nanotubes survive high currents (up to 1 mA, i.e., current density on the order of 10(9) A/cm2). In situ electron microscopy shows that a relatively large fraction of the nanotubes do not conduct (even at high bias), consistent with the existence of semiconducting nanotubes. Discrepancies with other measurements are most likely due to damage caused to the outer layer(s) of the nanotubes during processing. The measured mean free path of clean, undamaged arc-produced multiwalled carbon nanotubes is several orders of magnitude greater than that for metals, making this perhaps the most significant property of carbon nanotubes.