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DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

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DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

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Neuroblastoma (NB) is the most common extra cranial solid tumor of childhood and often lethal in childhood. Clinical and biologic characteristics that are independently prognostic of outcome in NB are currently used for risk stratification to optimally the therapy. It includes age at diagnosis, International Neuroblastoma Staging System tumor histopathology and MYCN amplification. However, even in patients with theoretically good prognosis, such as localized tumor and non-amplified MYCN, either disease progress or recurrence may occur. Potential genetic determinants of this unfavorable behavior are not yet fully clarified. The presence of elevated expression of AHCY, PKMYT1, and BLM has accompanied poor prognosis MYCN-amplified neuroblastoma patients. Considering the potential implication of these genes on the clinical management of NB, we hypothesize that the identification of genetic variations may have significant impact during development of the recurrent or progressive disease. Using targeted DNA sequencing, we analyzed the mutation profiles of the genes PKMYT1, AHCY, and BLM in tumor samples of five patients with MYCN amplified and 15 MYCN non-amplified NB. In our study, BLM germline variants were detected in two patients with MYCN-non-amplified neuroblastoma. Our data allow us to hypothesize that, regardless of MYCN status, these mutations partially abolish BLM protein activity by impairing its ATPase and helicase activities. BLM mutations are also clinically relevant because BLM plays an important role in DNA damage repair and the maintenance of genomic integrity. We also found a novel variant in our cohort, PKMYT1 mutation localized in the C-terminal domain with effect unknown on NB. We hypothesize that this variant may affect the catalytic activity of PKMYT1 in NB, specifically when CDK1 is complexed to cyclins. The prognostic value of this mutation must be further investigated. Another mutation identified was a nonsynonymous variant in AHCY. This variant may be related to the slow progression of the disease, even in more aggressive cases. It affects the maintenance of the catalytic capacity of AHCY, leading to the consequent functional effects observed in the NB patients studied. In conclusion, our hypothesis may provide that mutations in BLM, AHCY and PKMYT1 genes found in children with MYCN-amplified or MYCN-non amplified neuroblastomas, may be associated with the prognosis of the disease.

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This article discusses a telemedicine model for emerging countries, through the description of ONCONET, a telemedicine initiative applied to pediatric oncology in Brazil. The ONCONET core technology is a Web-based system that offers health information and other services specialized in childhood cancer such as electronic medical records and cooperative protocols for complex treatments. All Web-based services are supported by the use of high performance computing infrastructure based on clusters of commodity computers. The system was fully implemented on an open-source and free-software approach. Aspects of modeling, implementation and integration are covered. A model, both technologically and economically viable, was created through the research and development of in-house solutions adapted to the emerging countries reality and with focus on scalability both in the total number of patients and in the national infrastructure.

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To evaluate the impact of chemotherapy and surgery on the outcome of osteosarcoma (OS) of the extremities and to identify prognostic factors in Brazilian patients. A total of 225 patients with metastatic and nonmetastatic OS of the extremities were enrolled and assessed in two consecutive studies designed and implemented by the Brazilian Osteosarcoma Treatment Group. The 5-year survival and event-free survival rates for the 209 assessable patients were 50.1% and 39%, respectively; for the 178 patients with nonmetastatic disease at diagnosis, the rates were 60.5% and 45.5%, respectively. The multivariate analysis showed that the following variables were associated with a shorter survival: metastases at diagnosis (P < .001), necrosis grades 1 and 2 (P = .046), and tumor size (P = .0071). The overall 5- and 10-year survival rates were lower than the rates reported in North American and European trials. A pattern of advanced disease at diagnosis was often present, with a high proportion of patients having metastases (20.8%) and large tumor size (42.9%). However, these features were not necessarily associated with longer duration of prediagnostic symptoms. These findings were considered in the strategic planning of the current Brazilian cooperative study, with the aim of improving survival and quality of life of a large number of patients with OS.

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OBJECTIVE: To evaluate quality of life in children and adolescents with acute lymphocytic leukemia (ALL) and juvenile rheumatoid arthritis (JRA). MATERIAL AND METHODS: We administered the Children's Global Assessment Scale (CGAS), the Vineland Adaptative Behavior Scale (VABS) and the Autoquestionnaire qualité de vie enfant imagé (AUQEI) to a sample of 28 children with ALL, 28 children with JRA, and 28 healthy controls, aged 4 to 13 years old, who were diagnosed between 1 and 5 years previously. RESULTS: Slight differences were found in age between patients with ALL and those with JRA. No significant differences were found in time since diagnosis or in CGAS scores. A significant difference was found in VABS global scores, as well as in VABS communication domain scores. No significant differences were found in VABS daily living skills domain scores between patients with ARJ and healthy controls. No significant differences were found among the groups in VABS socialization domain scores or in AUQEI scores. CONCLUSION: In our study, chronically ill children clearly performed worse in adaptative behavior development. Nevertheless, their quality of life was similar to that of healthy controls. Appropriate methods to identify pediatric patients' perception of their illnesses and treatment should be urgently developed.

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Objetivo. Evaluar la calidad de vida de niños y adolescentes portadores de leucemia linfocítica aguda (LLA) y artritis reumatoide juvenil (ARJ).Material y métodos. Se aplicó la Children's Global Assessment Scale (CGAS), la Vineland Adaptative Behavior Scale (VABS) y el Autoquestionnaire Qualité de Vie Enfant Imagé (AUQEI) en 28 portadores de LLA, 28 portadores de ARJ y 28 escolares sanos pareados, de 4 a 13 años incompletos y diagnóstico entre 1 y 5 años. Resultados. Hubo discreta diferencia entre los grupos LLA y ARJ respecto a la edad. No hubo diferencias significativas en relación al tiempo de tratamiento, ni a la puntuación de la CGAS. Hubo diferencia significativa en la puntuación total de la VABS, así como del dominio comunicacional de la VABS. La diferencia ente los grupos ARJ y Sanos en relación a la puntuación de la VABS, dominio de actividades de vida cotidiana, no fue significativa. No hubo diferencia significativa entre los grupos respecto a la puntuación del dominio socialización de la VABS ni del AUQEI. Conclusión. En nuestro estudio, es nítido el peor desempeño de los niños crónicamente enfermos en lo que se refiere al desarrollo de comportamientos adaptables. No obstante, refieren una calidad de vida compatible con los controles sanos. Urge que se desarrollen métodos de evaluación habilitados en captar la percepción de la enfermedad y del tratamiento proveniente del propio paciente pediátrico (AU)

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A balanced de novo translocation t(X;1) is described in a girl with severe haemophilia B. The translocated X was shown cytologically to be preferentially active, and methylation analysis of the DXS255 locus confirmed the skewed X-inactivation with the paternal allele being the active one. Cytogenetic and molecular analysis showed that this chromosomal rearrangement led to the deletion of at least part of the factor IX gene. Therefore, the girl was heterozygous for factor IX deficiency and expression of her clinical phenotype was the result of the inactivation of the normal maternal X chromosome. The localization of one of the X chromosome translocation breakpoints in YAC clone 957F9, that was demonstrated to map distally to the factor IX gene, revealed the complexity of this chromosomal rearrangement.

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Bone marrow transplant is a relatively new procedure to treat recently considered incurable diseases. One important part of the procedure is the process of harvesting the donor bone marrow. We are developing a virtual reality simulator for bone marrow harvest that integrates interactive stereo visualization and force feedback techniques. The main objective is to offer a low cost virtual reality system to boost current adopted training methodologies for bone marrow harvesting.

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The authors report the case of a 4-year-old boy with a diagnosis of stage IV neuroblastoma (NB), who had been treated with 6 cycles of cyclophosphamide, doxorubicin, cisplatin, and etoposide for 12 months. The patient reached partial remission and presented a diagnosis of acute myelomonocytic leukemia (M4 AML), confirmed by immunophenotyping. After 2 months of therapy for leukemia, the child died with both malignancies in activity. A necropsy histologically confirmed the simultaneity of the two diseases. The authors review the possibilities of this association. The review leads to the conclusion that AML can occur as a secondary malignancy after the onset of the neuroblastoma, or be suggested by a misdiagnosis. The simultaneous occurrence of both as described here is not, however, found in the literature, to the best of the authors' knowledge.

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Symptomatic involvement of the gastrointestinal (GI) tract as a prominent symptom in Langerhans' cell histiocytosis (LCH) is uncommon, occurring in less than 1 to 5 percent of all cases, even when the disease is in its disseminated form. Up to now, there have been reports of 18 cases of LCH with GI manifestations, including our 2 cases, with diarrhea (77.7 percent), protein-losing enteropathy (33.3 percent) and bloody stool being the most frequent findings. The authors present two patients with severe diarrhea and refractory hypoalbuminemia, and with the protein-losing enteropathy documented by Cr51-labeled albumin studies. A review of the literature indicated that the presence of GI symptoms is often associated with systemic disease as well as with poor prognosis, mainly under 2 years of age. Radioisotopes are useful for documenting protein loss in several diseases with high specificity and sensitivity, and their utilization in the cases reviewed here permitted diagnoses in 6 children, as well as improved therapeutic management

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Symptomatic involvement of the gastrointestinal (GI) tract as a prominent symptom in Langerhans' cell histiocytosis (LCH) is uncommon, occurring in less than 1 to 5% of all cases, even when the disease is in its disseminated form. Up to now, there have been reports of 18 cases of LCH with GI manifestations, including our 2 cases, with diarrhea (77.7%), protein-losing enteropathy (33.3%) and bloody stool being the most frequent findings. The authors present two patients with severe diarrhea and refractory hypoalbuminemia, and with the protein-losing enteropathy documented by Cr51-labeled albumin studies. A review of the literature indicated that the presence of GI symptoms is often associated with systemic disease as well as with poor prognosis, mainly under 2 years of age. Radioisotopes are useful for documenting protein loss in several diseases with high specificity and sensitivity, and their utilization in the cases reviewed here permitted diagnoses in 6 children, as well as improved therapeutic management.

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BACKGROUND: Chemotherapy has dramatically improved the rates of cure and survival of patients with localized and metastatic osteosarcoma. Nonetheless, the number of chemotherapeutic agents active against osteosarcoma is limited to doxorubicin, cisplatin, high-dose methotrexate, and ifosfamide. Carboplatin, a cisplatin analogue, has been tested as a single agent in patients with recurrent osteosarcoma or as part of multiagent chemotherapy in newly diagnosed patients. PROCEDURE: We tested the activity and toxicity of two cycles of intraarterial carboplatin as a "window therapy" (600 mg/m2 per cycle) in 33 consecutive patients with extremity osteosarcoma before the start of multiagent chemotherapy. Response was based on clinical (tumor diameter, local inflammatory signs, and range of motion) and radiological parameters (plain local films and arteriographic studies prior to drug administration). RESULTS: Patients' age ranged between 8 and 18 years (median age 13 years). Primary tumor originated from the femur (15 patients), tibia (10 patients), fibula (4 patients), humerus (3 patients), and calcaneus (1 patient). Only 7 patients (21%) had metastatic disease at diagnosis (5 in the lung and 2 in other bones). A favorable clinical and radiological response was documented in 81% and 73% of the patients, respectively. Clinical and radiological progression occurred in 12% and 9% of the patients, respectively. Seventeen of the patients remain alive and disease-free. Survival and event-free survival at 3 years for nonmetastatic patients are 71% (SE = 9%) and 65% (SE = 9%), respectively; for metastatic patients, the figures are 17% (SE = 15%) and 14% (SE = 13%), respectively. CONCLUSIONS: We conclude that carboplatin is an active agent in the treatment of newly diagnosed extremity osteosarcoma.

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The MYCN oncogene is amplified in 20% of childhood neuroblastoma and is associated independently with poor prognosis. Alteration of the p53 tumor supressor gene, in contrast, occurs infrequently in these tumors. In this report, we described a 3-year-old girl with stage IV neuroblastoma. Molecular analysis revealed, both MYCN gene amplification and a point mutation of the p53 tumor supressor gene. To our knowledge, this is the first reported case of neuroblastoma with genetic alterations of both these genes.

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The initial results of 19 autologous and 1 syngeneic bone marrow transplantations, done in children with neuroblastomas (14), non-Hodgkin's lymphomas (3), Ewing sarcoma (1), acute lymphocytic (1) and non-lymphocytic (1) leukemias, pioneerely started in Brazil in February, 1987, and specially after the beginning of the ICR Marrow Transplantation Program, in October, 1989, are here described. Methodology, toxicity and survival are discussed. The efforts for establishing a high technology program in a public and universitarian institution, deeply supported by the community, are emphasized. Future directions are also discussed.

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We present the case of a child with acute lymphoid leukemia (ALL) who was morphologically classified as FAB L1 (PAS and peroxidase were negative). Remission was achieved with an ALL-type protocol (GBTLI). Five months after the discontinuation of therapy, the patient presented mixed leukemia (CD10, CD19, CD13 and CD33 were positive) with t (9;11) (p21;q23) translocation. Unfortunately, as cytogenetic and immunophenotype studies were not performed at diagnosis, two possibilities could be considered for the relapse; secondary mixed leukemia with clonal chromosome changes, or mixed leukemia from the beginning.

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Deletion 11q23-->qter and duplication 12q23-->qter are described in a boy with neuroblastoma, multiple congenital anomalies, and mental retardation. The patient has clinical manifestations of 11q deletion and 12q duplication syndromes. The possible involvement of the segment 11q23-->24 in the cause of the neuroblastoma is discussed.

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Calcification in lymphoma before treatment or after chemotherapy is extremely rare. There have been scarse reports of calcified masses due to Hodgkin and non-Hodgkin lymphomas, originating in the main lymphatic chains of the mediastinum and retroperitoneum. We report a case of primarily extra-nodal (pulmonary) non-Hodgkin lymphoma with calcification prior to current treatment.

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PURPOSE AND METHODS: Thirty-nine consecutive children (age, 2 to 11 years) with nonlymphoblastic (NL) lymphomas were treated uniformly with chemotherapy based on the LNH-II-85 protocol. The protocol consisted of a remission-induction phase that lasted 30 days and started with cyclophosphamide (CTX) 1.2 g/m2 on day 1, followed by vincristine (VCR) 1.5 mg/m2 on days 3, 10, 17, and 24, daunomycin (DAUNO) 60 mg/m2 on days 12 and 13, and prednisone 40 mg/m2/d for 30 days. If a complete remission was achieved, an intensification regimen was given that consisted of eight courses of teniposide (VM-26) 165 mg/m2 plus cytarabine (ARA-C) 300 mg/m2 every 4 days according to bone marrow tolerance. A continuation phase was subsequently started, with alternating courses of thioguanine (6-TG) 300 mg/m2/d for 4 days plus CTX 1.2 g/m2 on day 5; hydroxyurea 2.5 g/m2/d for 4 days plus DAUNO 45 mg/m2 on day 5; VCR 1.5 mg/m2 plus methotrexate (MTX) 120 mg/m2 (24 hours apart); mercaptopurine (6-MP) 500 mg/m2/d for 4 days plus MTX 40 mg/m2; and VM-26 plus ARA-C for 3 courses (4 days apart), by the end of 48 weeks. CNS prophylaxis consisted of intrathecal administration of MTX, ARA-C, and dexamethasone according to age, administered three times during remission induction and every 6 weeks afterwards. RESULTS: By the end of the analysis in July 1991, 38 of 39 patients had attained a complete remission and 36 were event-free survivors. Two failures that occurred after completion of therapy were second malignancies (acute lymphocytic leukemia and acute nonlymphocytic leukemia). CONCLUSION: These results are significantly better than those obtained with less intensive former regimens performed in our institution before the availability of VM-26. The favorable impact of an intense consolidation phase with VM-26 is remarkably exemplified by three additional patients not included in this study whose families withdrew them from therapy after the intensification phase, all three of whom have been in remission.

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