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The article explores the concept of division by a natural number without the axiom of choice in mathematics. It introduces the principles of "shoe division" and "sock division" as alternative versions of division by n. The text discusses the relationship between sock division and multiplication, presenting a theorem that proves their equivalence. It also explores the implications of sock division for bundles and the different interpretations of multiplication without the axiom of choice. The article concludes with a question about the relationship between divisibility and sock division in ZF set theory. [Extracted from the article]

Blood Brain Barrier (BBB) breakdown is a secondary form of brain injury which has yet to be fully elucidated mechanistically. Existing research suggests that breakdown of tight junction proteins between endothelial cells is a primary driver of increased BBB permeability following injury, and intercellular signaling between primary cells of the neurovascular unit: endothelial cells, astrocytes, and pericytes; contribute to tight junction restoration. To expound upon this body of research, we analyzed the effects of severely injured patient plasma on each of the cell types in monoculture and together in a triculture model for the transcriptional and translational expression of the tight junction proteins Claudins 3 and 5, (CLDN3, CLDN5) and Zona Occludens 1 (ZO-1). Conditioned media transfer studies were performed to illuminate the cell type responsible for differential tight junction expression. Our data show that incubation with 5% human ex vivo severely injured patient plasma is sufficient to produce a differential response in endothelial cell tight junction mRNA and protein expression. Endothelial cells in monoculture produced a significant increase of CLDN3 and CLDN5 mRNA expression, (3.98 and 3.51 fold increase vs. control respectively, p<0.01) and CLDN5 protein expression, (2.58 fold change vs. control, p<0.01), whereas in triculture, this increase was attenuated. Our triculture model and conditioned media experiments suggest that conditioned media from astrocytes and pericytes and a triculture of astrocytes, pericytes and endothelial cells are sufficient in attenuating the transcriptional increases of tight junction proteins CLDN3 and CLDN5 observed in endothelial monocultures following incubation with severely injured trauma plasma. This data suggests that inhibitory molecular signals from astrocytes and pericytes contributes to prolonged BBB breakdown following injury via tight junction transcriptional and translational downregulation of CLDN5. [ABSTRACT FROM AUTHOR]

This paper is an investigation of the relationship between Gödel's second incompleteness theorem and the well-foundedness of jump hierarchies. It follows from a classic theorem of Spector that the relation {(A,B) ∈ R2 : OA &#8804:H B} is well-founded. We provide an alternative proof of this fact that uses Gödel's second incompleteness theorem instead of the theory of admissible ordinals. We then derive a semantic version of the second incompleteness theorem, originally due to Mummert and Simpson, from this result. Finally, we turn to the calculation of the ranks of reals in this well-founded relation. We prove that, for any A ∈ R, if the rank of A is α, then ω1A is the (1 + α)th admissible ordinal. It follows, assuming suitable large cardinal hypotheses, that, on a cone, the rank of X is ω1X. [ABSTRACT FROM AUTHOR]

Summary: Congenital sideroblastic anaemia (CSA) is a rare disease caused by germline mutations of genes involved in haem and iron‐sulphur cluster formation, and mitochondrial protein biosynthesis. We performed a retrospective multicentre European study of a cohort of childhood‐onset CSA patients to explore genotype/phenotype correlations. We studied 23 females and 20 males with symptoms of CSA. Among the patients, the most frequently mutated genes were ALAS2 (n = 10; 23·3%) and SLC25A38 (n = 8; 18·6%), causing isolated forms of microcytic anaemia of varying severity. Five patients with SLC19A2 mutations suffered from thiamine‐responsive megaloblastic anaemia and three exhibited the 'anaemia, deafness and diabetes' triad. Three patients with TRNT1 mutations exhibited severe early onset microcytic anaemia associated with thrombocytosis, and two exhibited B‐cell immunodeficiency, inflammatory syndrome and psychomotor delay. The prognoses of patients with TRNT1 and SLC2A38 mutations were generally dismal because of comorbidities or severe iron overload. No molecular diagnosis could be established in 14/43 cases. This study emphasizes the frequency of ALAS2 and SLC25A38 mutations and provides the largest comprehensive analysis to date of genotype/phenotype correlations in CSA. Further studies of CSA patients with data recorded in an international registry would be helpful to improve patient management and establish standardized guidelines. [ABSTRACT FROM AUTHOR]

Childhood autoimmune haemolytic anaemia ( AIHA) requires second-line immunosuppressive therapy in 30-50% of cases. It appears that rituximab is indicated in such circumstances. This prospective national study reports the practice, efficacy and tolerance of rituximab in children with isolated AIHA and AIHA in the setting of Evans syndrome ( ES). Sixty-one children were given rituximab between 2000 and 2014. The median interval from diagnosis to rituximab was 9·9 [interquartile range ( IQR) 1·6-28·5] months. Forty-six patients responded (75%) and the 6-year relapse-free survival ( RFS) was 48%. Twenty patients relapsed at a median interval of 10·8 ( IQR 3·9-18·7) months, rituximab allowed steroid withdrawal in 44/61 (72%) of children. In isolated AIHA, complete response and 6-year RFS were significantly higher than in ES ( P < 0·05). Ten out of 61 patients were infants, seven of who responded with a 6-year RFS of 71%. Among patients without immunoglobulin substitution before rituximab, 4 are still receiving substitutions. Five patients died, including one potentially attributable to rituximab. This large observational series of childhood AIHA established the rituximab benefit-risk ratio, allowing steroid withdrawal, with 37% of long-term responders, mainly in isolated AIHA. All subgroups of patients drew benefit. Our long-term results indicate the baseline to be challenged by new treatment approaches. [ABSTRACT FROM AUTHOR]

The French national cohort of children with Langerhans cell histiocytosis ( LCH) has included 1478 patients since it was established in 1983. LCH therapeutic strategies substantially changed in 1998, so we have divided the cohort into two 15-year periods. Starting in 1998, therapy duration increased from 6 to 12 months, repeated induction therapy was performed in cases showing a poor response to the first induction with vinblastine and steroids, and refractory disease in a risk organ ( RO+) was treated with cladribine and cytarabine. A total of 483 (33%) patients were enrolled before 1998, and 995 (67%) after 1998. Five-year survival was 96·6% (95% confidence interval: 95·4-97·5%) overall, improving from 92% pre-1998 to 99% post-1998 ( P < 0·001 adjusted to disease extent). This change was supported by an increase in 5-year survival from 60% to 92% in the RO+ group. Survival was particularly associated with cladribine and cytarabine among refractory RO+ patients. Disease reactivation was slightly less frequent after 1998, due to better enrolment of single-system patients, extended therapy duration, and more efficient second-line therapy. The crude rates of endocrine and neurological sequelae (the most frequent sequelae) appeared to improve over time, but this difference was not observed when the analysis was stratified by disease extent. [ABSTRACT FROM AUTHOR]

Acute lymphoblastic leukemia of T cell lineage (T-ALL) is an aggressive malignant disease which accounts for 15 % of childhood ALL. T(11;14) is the more frequent chromosomal abnormality in childhood T-ALL, but its prognostic value remained controversial. Our aim was to analyze the outcome of childhood T-ALL with t(11;14) to know if the presence of this translocation is associated with a poor prognosis. We conducted a retrospective study from a series of 20 patients with t(11;14), treated in two consecutive trials from the European Organization for Research and Treatment of Cancer Children Leukemia Group over a 19-year period from 1989 to 2008. There were no significant differences between the 2 consecutive groups of patients with t(11;14) regarding the clinical and biological features at diagnosis. Among 19 patients who reached complete remission, 9 patients relapsed. We noticed 7 deaths all relapse- or failure-related. In the 58881 study, a presence of t(11;14) was associated with a poor outcome with an event-free survival at 5 years at 22.2 % versus 65.1 % for the non-t(11;14) T-ALL (p = 0.0004). In the more recent protocol, the outcome of T-ALL with t(11;14) reached that of non-t(11;14) T-ALL with an event-free survival at 5 years at 65.5 versus 74.9 % (p = 0.93). The presence of t(11;14) appeared as a poor prognostic feature in the 58881 trial whereas this abnormality no longer affected the outcome in the 58951 study. This difference is probably explained by the more intensive chemotherapy in the latest trial. [ABSTRACT FROM AUTHOR]

In this work we describe a novel method to prepare multi-domain metal–metal oxide heterostructured nanoparticles (NPs). We investigated the ability of Ni(acac)2 to undergo galvanic exchange with pre-synthesized metallic α-Fe NPs. Findings indicate that an asymmetric heterostructure emerges from the exchange, which is followed by rapid oxidation to form a NiFe–M3O4 (M = Fe, Ni) alloy-oxide microstructure. Nucleation and growth was monitored using UV-vis and TEM, and crystal evolution, composition change, and oxidation states were measured by XRD and XPS respectively. Galvanic exchange and growth was studied by varying Ni : Fe molar feed ratios during synthesis. The findings indicate that at low Ni : Fe ratios, the NP forms multiple domains of oxides, whereas at higher ratios form regions with novel Ni–NiFe–M3O4 interfaces. These new heterostructures were highly magnetic, and the extent of magnetization was proportional to composition and morphology, where NPs prepared at high Ni : Fe feed ratios resulted in decreased saturation magnetization and increased magnetic hysteresis. The nickel deposition and NP growth mechanism was considered as a combination of both galvanic exchange and reduction, and the observed rapid oxidation of the remaining α-Fe core was considered in light of electron density change at the heterostructures interfaces. Nanomaterials like these may find use as components in magnetic storage and spintronic devices, probes in biomedicine, additives in corrosion resistant coatings, and even as 3D printing inks. [ABSTRACT FROM AUTHOR]

The main aim of the Leucémies de l’Enfant et l’Adolescent (LEA) project (Childhood and Adolescent Leukaemia) is to study the determinants (medical, socioeconomic, behavioural and environmental) of medium- and long-term outcomes of patients treated for childhood acute leukaemia (AL). The LEA study began in 2004 and is based on a French multicentric prospective cohort. Included are children treated for AL since January 1980 (incident and prevalent cases), surviving at month 24 for myeloblastic AL and lymphoblastic AL grafted in first complete remission or at month 48 for lymphoblastic AL not grafted in first complete remission. Information is collected during specific medical visits and notably includes the following data: socioeconomic data, AL history, physical late effects (such as fertility, cardiac function and metabolic syndrome) and quality of life. Data are collected every 2 years until the patient is 20 years old and has had a 10-year follow-up duration from diagnosis or last relapse. Thereafter, assessments are planned every 4 years. In active centres in 2013, eligible patients number more than 3000. The cohort has already included 2385 survivors, with rate of exhaustiveness of almost 80%. Data access can be requested from principal coordinators and must be approved by the steering committee. [ABSTRACT FROM PUBLISHER]

Background The purpose of this study was to describe the natural history of severe congenital neutropenia (SCN) in 14 patients with G6PC3 mutations and enrolled in the French SCN registry. Methods Among 605 patients included in the French SCN registry, we identified 8 pedigrees that included 14 patients with autosomal recessive G6PC3 mutations. Results Median age at the last visit was 22.4 years. All patients had developed various comordibities, including prominent veins (n = 12), cardiac malformations (n = 12), intellectual disability (n = 7), and myopathic syndrome with recurrent painful cramps (n = 1). Three patients developed Crohn's disease, and five had chronic diarrhea with steatorrhea. Neutropenia was profound (<0.5 × 109/l) in almost all cases at diagnosis and could marginally fluctuate. The bone marrow smears exhibited mild late-stage granulopoeitic defects. One patient developed myelodysplasia followed by acute myelogenous leukemia with translocation (18, 21) at age 14 years, cured by chemotherapy and hematopoietic stem cell transplantation. Four deaths occurred, including one from sepsis at age 5, one from pulmonary late-stage insufficiency at age 19, and two from sudden death, both at age 30 years. A new homozygous mutation (c.249G > A /p.Trp83*) was detected in one pedigree. Conclusions Severe congenital neutropenia with autosomal recessive G6PC3 mutations is associated with considerable clinical heterogeneity. This series includes the first described case of malignancy in this neutropenia. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the potential involvement of fertility treatments and other conditions of becoming pregnant (infertility, getting pregnant on birth control, maternal history of fetal loss) and folic acid supplements in the etiology of childhood leukemia (CL). Methods: The ESTELLE study included 747 cases of CL [636 cases of acute lymphoblastic leukemia (ALL) and 100 of acute myeloblastic leukemia (AML)] diagnosed in France in 2010-2011 and 1,421 population controls frequency-matched with the cases on age and gender. Data were obtained from structured telephone questionnaires administered to mothers. The odds ratios (OR) and their 95 % confidence intervals were estimated using unconditional regression models adjusted for potential confounders. Results: CL was not associated with difficulty in becoming pregnant [OR 0.9 (0.7-1.2)], in vitro fertilisation [OR 0.6 (0.3-1.5)] or the use of any fertility treatment [OR 0.8 (0.5-1.1)] for the index pregnancy. CL was not significantly associated with becoming pregnant on contraception [OR 1.2 (0.8-1.8)], but a positive association was observed for third generation oral contraception [OR 4.3 (1.2-16.2)]; however, the result is based on small numbers. Folic acid supplementation during pregnancy was not associated with CL, but an inverse borderline association was observed for supplementation initiated in the 3 months preceding pregnancy [OR 0.7 (0.5-1.0)]. In addition, maternal histories of stillbirth and miscarriage were associated with ALL [OR 2.6 (1.1-5.9)] and AML [OR 1.8 (1.1-2.8)], respectively. Conclusions: The findings do not suggest that infertility and fertility treatments are risk factors for CL. They suggest that maternal histories of stillbirth and miscarriage may be more frequent among mothers of CL cases and that folic acid supplementation during preconception may reduce the risk of CL. [ABSTRACT FROM AUTHOR]

This study aimed to describe the clinical features and outcome of anaplastic large cell lymphoma ( ALCL) with leukaemic presentation in children. Among 267 patients included in the French paediatric ALCL database between 1989 and 2012, nine (3%) were described as having cytologically detectable circulating tumour cells. Clinical features combined fever (8/9), nodal and extra-nodal disease (9/9), including hepato-splenic (9/9) and lung involvement (7/9). The level of hyperleucocytosis ranged from 30 to 120 × 109/l, with 12-90% of tumour cells. Diagnosis relied on a lymph node biopsy, with a positive ALK+ antibody immunostain in all nine cases, a T-cell immunophenotype in 7/9 cases and CD3 positivity in 5/9 cases. A small cell component was present in 6/9 cases. Only four patients achieved a complete remission with first-line therapy and 3/4 relapsed. Four patients are alive with a median follow-up of 31 months, two of them after allogeneic haematopoietic stem cell transplantation ( HSCT), and five patients died, two of them of disease. In conclusion, ALCL with leukaemic presentation is very unusual and should be considered as high-risk lymphoma requiring new therapeutic strategies. The respective role of new agents and allogeneic HSCT in first complete remission still has to be assessed. [ABSTRACT FROM AUTHOR]

Minimal residual disease ( MRD) is a major predictive factor of the cure rate of acute lymphoblastic leukaemia ( ALL). Haematopoietic cell transplantation is a treatment option for patients at high risk of relapse. Between 2005 and 2008, we conducted a prospective study evaluating the feasibility and efficacy of the reduction of immunosuppressive medication shortly after a non- ex vivo T depleted myeloablative transplantation. Immunoglobulin (Ig)H/T-cell receptor MRD 30 d before transplant could be obtained in 122 of the 133 cases of high-risk paediatric ALL enrolled. There were no significant demographic differences except remission status (first or second complete remission) between the 95 children with MRD <10−3 and the 27 with MRD ≥10−3. Multivariate analysis identified sex match and MRD as being significantly associated with 5-year survival. MRD ≥10−3 compromised the 5-year cumulative incidence of relapse (43·6 vs. 16·7%). Complete remission status and stem cell source did not modify the relationship between MRD and prognosis. Thus, pre-transplant MRD is still a major predictor of outcome for ALL. The MRD-guided strategy resulted in survival for 72·3% of patients with MRD<10−3 and 40·4% of those with MRD ≥10−3. [ABSTRACT FROM AUTHOR]

We correct an error in the statement of a theorem in our paper ''Incompleteness and jump hierarchies'' [Proc. Amer. Math. Soc. 148 (2020), pp. 4997-5006]. [ABSTRACT FROM AUTHOR]

A minority of children with chronic immune thrombocytopenia ( ITP) require therapeutic intervention to prevent haemorrhagic risk. This retrospective national study evaluated romiplostim in childhood non-responsive or refractory chronic ITP. Between 2009 and 2012, 10 patients whose Buchanan score was 3-4 were treated with romiplostim. The median duration of thrombocytopenia was 1·9 years (0·8-15). The median duration of romiplostim treatment was 9 months (3-36). A response was observed in 5/10 patients (one complete, four partial). No serious adverse effect was noticed. The long-term benefit/risk balance of this innovative treatment is currently recorded by Centre de Référence National des Cytopénies Auto-immunes de l'Enfant. [ABSTRACT FROM AUTHOR]

There is little data available regarding children and adolescents with Hodgkin lymphoma (HL) who relapse after combined-modality treatment, even though they have a substantial chance of cure. The purpose of this national retrospective study was to evaluate the outcome of patients with recurrent/refractory HL and determine adverse prognostic factors. From 1990 to 2006, 70 patients (median age 13·9 years) with refractory ( n = 31) or first relapse ( n = 39) HL were identified. Median time from end of treatment to relapse was 6 months (3-56). Relapses occurred in irradiated areas in 43/70 patients. Salvage therapy consisted of chemotherapy and 50 patients received high-dose chemotherapy with autologous stem cell transplantation. Radiotherapy was performed in 29 cases, tandem autologous transplantation in five and allograft in three. With a median follow-up of 40 months (2-140), significant prognostic factors were time to progression/relapse and response to therapy before autograft. Event-free survival and overall survival in patients with refractory disease, early relapse and late relapse were 35 ± 9%, 67 ± 11%, 76 ± 10% and 48 ± 11%, 89 ± 7% and 80 ± 10%, respectively. As progression <3 months was a major adverse prognostic factor, novel therapeutic approaches are needed for this group of patients. By contrast, patients have substantial chance of long term second remission in case of relapse >3 months. [ABSTRACT FROM AUTHOR]

Background: Intensity modulated radiotherapy is an efficient radiotherapy technique to increase dose in target volumes and decrease irradiation dose in organs at risk. This last objective is mainly relevant in children. However, previous results suggested that IMRT could increase low dose, factor of risk for secondary radiation induced cancer. This study was performed to compare dose distributions with 3D-radiotherapy (3D-RT) and IMRT with tomotherapy (HT) in children with neuroblastoma. Seven children with neuroblastoma were irradiated. Treatment plans were calculated for 3D-RT, and for HT. For the volume of interest, the PTV-V95% and conformity index were calculated. Dose constraints of all the organs at risk and integral dose were compared. Results: The conformity index was statistically better for HT than for 3D-RT. PTV-V95% constraint was reached in 6 cases with HT compared to 2 cases with 3D-RT. For the ipsilateral kidney of the tumor, the V12 Gy constraint was reached for 3 patients with both methods. The values were lower with HT than with 3D-RT in two cases and higher in one case. The threshold was not reached for one patient with either technique, but the value was lower with HT than with 3D-RT. For the contralateral kidney of the tumors, the V12 Gy constraint was reached for all patients with both methods. The values were lower with HT than with 3D-RT in 5 of 7 children, equal in one patient and higher in one patient. The organ-at-risk volumes receiving low doses were significantly lower with 3D-RT but larger for the highest doses, compared to those irradiated with HT. The integral doses were not different. Conclusions: IMRT with HT allows a better conformity treatment, a more frequently acceptable PTV-V95% than 3D-RT and, concomitantly, a better shielding of the kidneys. The integral doses are comparable between both techniques but consideration of differences in dose distribution between the two techniques, for the organs at risk, has to be taken in account when validating treatment [ABSTRACT FROM AUTHOR]

The study investigated the role of factors considered related to the early stimulation of the immune system in the aetiology of childhood lymphoma. The national registry-based case-control study, Escale, was carried out in France over the period 2003-2004. Population controls were frequency matched with the cases on age and gender. Data were obtained from structured telephone questionnaires administered to mothers. Odds ratios (ORs) were estimated using unconditional regression models adjusted for potential confounders. Data from 128 cases of Hodgkin's lymphoma (HL) aged 5-14 years, 164 cases of non-Hodgkin's lymphoma (NHL) aged 2-14 years and 1,312 controls were analyzed. Negative associations were observed between HL and day care attendance [OR = 0.5 (0.2-1.2)] and between HL and repeated early common infections among non-breastfed children [OR = 0.3 (.2-0.7), p = 0.003] [OR for breastfed children: 1.0 (.5-2.1)], but not for the other factors investigated. Negative associations were observed between NHL and birth order 3 or more [OR = 0.7 (0.4-1.1)], prolonged breastfeeding [OR = 0.5 (0.3-1.0)], regular contact with farm animals [OR = 0.5 (0.3-1.0)], frequent farm visits in early life [OR = 0.6 (0.4-1.1)] and history of asthma [OR = 0.6 (0.3-1.1)]. In conclusion, the results partly support the hypothesis that an abnormal maturation of the immune system may play a role in childhood HL or NHL, and call for further investigations. [ABSTRACT FROM AUTHOR]

In children, lymphoblastic lymphomas represent 30% of Non-Hodgkin lymphomas (NHL), and approximately 15% are precursor B-cell lymphomas (PBLL). Our study evaluated their main clinical characteristics, evolution, and prognosis in three trials. From 1989 to 2008, 53 children with PBLL (median age 7·75 years) were included in three protocols: Malignant Lymphoma Therapy (LMT) 96, European Organization for Research and Treatment of Cancer (EORTC) 58881, and EORTC 58951 using Berlin-Frankfürt-Münster-derived acute lymphoblastic leukaemia (ALL) therapy. There were 10 stage I disease, 9 stage II, 9 stage III and 25 stage IV. Clinical presentation was heterogeneous with a majority of bone lesions and cutaneous or subcutaneous manifestations. At diagnosis 23 patients had bone marrow involvement, and only three had central nervous system involvement. The median follow-up was 74 months. At last follow-up, 45 patients were in continuous complete remission, whereas eight had progressed or had relapsed (7 Stages IV and 1 Stage III) and died. Two patients had a secondary neoplasia, and are still alive. Disease stage was a major prognostic factor, with better overall survival (OS) and event-free survival (EFS) ( P < 0·05) rates observed in patients with Stage I to III as compared to those with Stage IV. Treatment with protocols derived from ALL therapy are efficient with an 82% EFS and an 85% OS at 5 years. [ABSTRACT FROM AUTHOR]

The article discusses the impact of treatment on children with down syndrome associated acute lymphoblastic leukaemia and reduction drug doses. Topics discussed include toxicity caused corticosteroid therapy, especially dexamethasone to regulate immune suppression, white blood cell count or immunophenotype.

Partial splenectomy (PS) in children is a surgical option in haematological diseases and focal splenic tumours. The aim of this study was to describe the feasibility and the results of laparoscopic partial splenectomy in children in these two indications by a multicentric retrospective study. The authors reviewed the files of all children who underwent laparoscopic PS between March 2002 and September 2006 in two paediatric surgical centers. The data of 11 children were collected and included clinical presentation, age, gender, radiographic examinations, surgical procedure, need for blood transfusion and early complications. From March 2002 to September 2006, laparoscopic PS had been performed on 11 children (6 boys, 5 girls) aged 23 months to 11 years (mean 7, 9). Four children had splenic focal tumours and seven had haematological diseases: six hereditary spherocytosis (HS) and one hemoglobinosis E. During the surgical procedure for haematological diseases 75–80% of the splenic tissue was removed. When PS was performed for focal splenic tumours, the splenic remnant was around 70%. No preoperative complications occurred (no bleeding, no diaphragmatic injury). Neither preoperative nor conversion was necessary. One postoperative complication occurred (left pleural effusion) but required no further treatment. The mean hospital stay was 7.7 days (range from 3 days to 10 days). No infectious postoperative complications occurred; the mean follow up was 21.1 months (range 3–52 months). Laparoscopic partial splenectomy is feasible and safe in children with hypersplenism or focal splenic tumours. Partial splenectomy is a good way to prevent postsplenectomy infections by preservation of the immune role of spleen in children with haematological diseases. This technique performed for focal splenic tumours allows the surgeon to choose the size of the splenic remnant. [ABSTRACT FROM AUTHOR]

In our previous study, a frequent rearrangement at 4q12 has been identified by allelotyping in our large and homogeneous population of pediatric osteosarcomas and it was significantly linked to c-kit protein overexpression. To confirm and understand the involvement of KIT in this tumor, the next step of the study was designed to detect the potential mutations of KIT gene by sequencing the frequently mutated exons 6, 8, 10, 11, 13, 17 and 21 and, in case of unmutated samples, to confirm the genomic amplifications of the wild-type receptor by real-time quantitative PCR (QPCR). A new microsatellite and QPCR targeting PDGFRA was also added to check the accuracy of the 4q11-12 locus. These techniques were performed in 74 pediatric high-grade osteosarcomas treated with the OS94 protocol. Surprisingly, no mutations were found, but, only DNA amplification of KIT gene in the entire population. PDGFRA gene QPCR revealed an unexpected result of predominant deletions in the rearranged tumors. All these results confirm the major role of the 4q11-12 locus and specifically the involvement of c-kit wild-type receptor overexpression in pediatric osteosarcomas and leads us to believe that inhibitors targeting this receptor could have a therapeutic effect in a selected group of patients. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The identification of genes as markers for chromosome aberrations in specific tumors might facilitate oncogenesis mechanism comprehension, cancer detection, prediction of clinical outcomes, and response to therapy. Previous physiologic and oncologic data identified the TWIST gene as a marker for mesodermal derivative and bone tissue differentiation, but its contribution to bone malignancies has not been investigated. In the present study, search for genomic alterations in high-grade pediatric osteosarcomas was focused on the 7p21 region, and more specifically on the TWIST gene. In a cohort of 74 patients, we observed by allelotyping that 31 of 68 informative tumors were rearranged at the TWIST locus. Among them, analysis by quantitative PCR (QPCR) revealed that, surprisingly, mostly deletions (22/68), but also amplifications (9/68), of the TWIST gene were detected. Furthermore, deletions at TWIST were statistically correlated to other molecular abnormalities, like alterations at the APC or c-kit loci, as well as to clinical features such as a poor outcome. This work shows that the TWIST gene seemed to be involved in high-grade pediatric osteosarcomas and is a new marker with a possible initial predictive value. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Viral infection is an important cause of morbidity and mortality in the post-allograft period. Recently, a new therapeutic approach was developed in post-tranplant lymphoproliferative disorder (PTLD) induced by Epstein–Barr virus (EBV): the anti-CD20 monoclonal antibody or rituximab® . We performed a single-center study on the treatment effectiveness of rituximab in three EBV-induced PTLD and evaluated biologic data, such as T and B lymphocytes count, during PTLD development and treatment. Before PTLD treatment, blood cell profile showed a severe T lymphopenia with a progressive increase of CD8+ cells and B lymphopenia. Secondly, during treatment, there appeared a T response, as in primary EBV, and a regressive B lymphopenia. [ABSTRACT FROM AUTHOR]

Post-transplant lymphoproliferative disorder (PTLD) after haemopoietic stem cell transplantation is a serious complication that occurs in 8–22% of patients with high-risk factors. We retrospectively investigated tolerance and efficacy of humanized anti-CD20 monoclonal antibody (rituximab) as first-line treatment in 12 children with B-cell PTLD. At diagnosis, eight patients had tumoral involvement. The other four patients had fever, associated with raised Epstein–Barr virus (EBV) viral load and monoclonal gammopathy. Rituximab was given at the dose of 375 mg/m2 once a week by intravenous infusion (1–9 infusions). Only 1/48 infusions was associated with a grade 2 clinical adverse event. Eight out of 12 (66%) patients responded to the treatment and were in complete remission. All patients without tumoral involvement responded to the treatment. A rapid decrease in fever within 1 week was observed in all responders. Non-responders did not show any clinical response during the first week. Tumoral involvement and immunodepression seemed to be more marked in non-responders. Rituximab was an effective and well-tolerated treatment of B-cell PTLD. Early treatment before tumoral involvement seemed to be the most effective approach. Lack of rapid response should lead to intensification of PTLD treatment. Pre-emptive treatment should be considered and evaluated in further longitudinal multicentre studies. [ABSTRACT FROM AUTHOR]

We investigated the use of a new conditioning regimen followed by allogeneic bone marrow transplantation (BMT) for treating children with acute lymphoblastic leukaemia (ALL) after relapse within 6 months of the completion of therapy. One hundred and sixteen children with acute lymphoblastic leukaemia in second or subsequent complete remission (CR) underwent allogeneic bone marrow transplantation from HLA-identical siblings after a preparative regimen comprising total body irradiation (TBI), high-dose cytosine arabinoside and melphalan (TAM regimen). The Kaplan-Meier product-limit estimate (mean ± SE) of disease-free survival (DFS) at 7 years was 59.5 ± 9% (95% confidence interval). The estimated chance of relapse was 22.5 ± 15% with a median follow-up of 88.5 months (range 51–132). 26 patients (22.4%) died with no evidence of recurrent leukaemia, mainly from interstitial pneumonitis, veno-occlusive disease or acute graft-versus-host disease (GVHD). Three factors significantly affected DFS: acute GVHD, site of relapse and, for children in second remission after a marrow relapse, the disease status at the time of transplantation. The DFS were 59.02 ± 12.6%, 37.5 ± 19.8% and 77.4 ± 15% among patients in CR2 after a marrow relapse, in CR3 or in untreated partial marrow relapse, and in CR2 after an isolated CNS relapse, respectively. The lowest DFS was seen in children with acute GVHD grades 3–4. Two significant factors were associated with relapse: the marrow status at the time of transplantation and chronic GVHD. The relapse rate was lower among children in CR2 or with chronic GVHD. We conclude that transplantation after the TAM regimen is an effective therapy for this population with acceptable toxicity, particularly for children in second remission after a very early marrow relapse, or those with early isolated CNS involvement. [ABSTRACT FROM AUTHOR]

Focuses on a study that described fibrodysplasia ossificans progressiva (FOP), a rare autosomal dominant disorder. Regulation of bone morphogenetic protein 4 expression in FOP; Methodology; Results and discussion.

Background: Vinblastine (VBL) is the standard treatment for systemic Langerhans cell histiocytosis (LCH), but little is known about its efficacy in central nervous system (CNS) mass lesions.Methods: A retrospective chart review was conducted. Twenty patients from the French LCH Study Group register met the inclusion criteria. In brief, they had CNS mass lesions, had been treated with VBL, and were evaluable for radiologic response.Results: The median age at diagnosis of LCH was 11.5 years (range: 1-50). Intravenous VBL 6 mg/m2 was given in a 6-week induction treatment, followed by a maintenance treatment. The median total duration was 12 months (range: 3-30). Eleven patients received steroids concomitantly. Fifteen patients achieved an objective response; five had a complete response (CR: 25%), ten had a partial response (PR: 50%), four had stable disease (SD: 20%) and one patient progressed (PD: 5%). Of interest, four out of the six patients who received VBL without concomitant steroids achieved an objective response. With a median follow-up of 6.8 years, the 5-year event-free and overall survival was 61% and 84%, respectively. VBL was well-tolerated and there were no patient withdrawals due to adverse events.Conclusion: VBL, with or without steroids, could potentially be a useful therapeutic option in LCH with CNS mass lesions, especially for those with inoperable lesions or multiple lesions. Prospective clinical trials are warranted for the evaluation of VBL in this indication. [ABSTRACT FROM AUTHOR]