Electron Affinity Calculations for Thioethers

Previous work indicated that polyphenyl thioethers possessed chemical properties, related to their electron affinities, which could allow them to function as vapor phase lubricants (VPL). Indeed, preliminary tribological tests revealed that the thioethers could function as vapor phase lubricants but not over a wide temperature and hertzian pressure range. Increasing the electron affinity of the thioethers may improve their VPL properties over this range. Adding a substituent group to the thioether will alter its electron affinity in many cases. Molecular orbital calculations were undertaken to determine the effect of five different substituent groups on the electron affinity of polyphenyl thioethers. It was found that the NO2, F, and I groups increased the thioethers electron affinity by the greatest amount. Future work will involve the addition of these groups to the thioethers followed by tribological testing to assess their VPL properties

Effect of Threonine and the Bioactive Component of Saccharomyces Cerevisiae on the Productive Performance of the Broiler Cobb 500

This study was conducted in Chimborazo province, Riobamba Canton to evaluate the effect of threonine and the bioactive component of Saccharomyces cerevisiae on the productive performance of the broiler Cobb 500. A total of 270 one-day-old broiler chicken of both sexes were included, which corresponded to an experimental unit size of 15 birds. Two growth promoters were used for the treatments -- T1: Threonine (aminoacid) 200 g/Tn; and T2: bioactive oligosaccharides, obtained from the cell wall of selected strains of S. Cerevisiae (probiotic) 750 g/Tn. These were compared to a control group. The data were analyzed through Analysis of Variance (ADEVA). The separation of means was performed using the Tukey statistic at a level of significance of p < 0.05 and p < 0.01. The data were processed using the Infostat software version 2010. The results showed that the best productive yields were with treatment 2; the values for this treatment were: weight at 28 days: 1369.42 g; weight gain at 28 days: 48.90 g; food conversion at 28 days: 1.39 points; carcass weight: 2527.05 g; and yield to the carcass: 83.85%. Through the economic analysis, it was determined that the highest cost-benefit index was 1.30 USD with the application of T2. So according to the results, a better use of the nutrients that are present in the feed is achieved when bioactive components of S. cerevisiae are supplied in the diet of broiler chickens. Keywords: Threonine, Saccharomyces cerevisiae, productive performance, broiler, Cobb 500. RESUMEN Se realizó un experimento en la provincia de Chimborazo, Cantón Riobamba, para evaluar los efectos de treonina y componentes bioactivos de Saccharomyces cerevisiae sobre el comportamiento productivo en aves Cobb 500. Se utilizaron 270 pollitos mixtos Cobb 500 de un día de edad de ambos sexos, con un tamaño de unidad experimental de 15 aves. Para los tratamientos se manejaron dos promotores de crecimiento, T1: Treonina (aminoácido) 200 g/Tn y T2: Oligosacáridos bioactivos, obtenidos a partir de la pared celular de cepas seleccionadas de S. Cerevisiae750 g/Tn; frente a un testigo (T0). Los datos obtenidos fueron sometidos a Análisis de Varianza (ADEVA); la separación de medias se realizó mediante el estadístico Tukey a un nivel de significancia (p < 0,05) y (p < 0,01); los datos se procesaron mediante el software Infostat versión 2010. Los resultados muestran los mejores rendimientos productivos con el Tratamiento 2, para los parámetros: peso a los 28 días 1369,42 g; ganancia de peso a los 28 días 48,90 g; y conversión alimenticia a los 28 días con 1,39 puntos; así como peso a la canal 2527,05 g; y rendimiento a la canal 83,85%. Mediante el análisis económico se determinó que el mayor índice beneficio costo fue de 1,30 USD con la aplicación del T2. Lo que brinda un indicativo que mediante el suministro de componentes bioactivos de S. cerevisiae en la dieta de pollos broiler, se logra un mejor aprovechamiento de los nutrientes que se encuentran presentes en el alimento, lo que se refleja en los parámetros productivos. Palabras clave: treonina, Saccharomyces cerevisiae, comportamiento productivo, broilers, Cobb 500

Non-Hodgkin Lymphoma in Children and Adolescents: Progress Through Effective Collaboration, Current Knowledge, and Challenges Ahead

Non-Hodgkin lymphoma is the fourth most common malignancy in children, has an even higher incidence in adolescents, and is primarily represented by only a few histologic subtypes. Dramatic progress has been achieved, with survival rates exceeding 80%, in large part because of a better understanding of the biology of the different subtypes and national and international collaborations. Most patients with Burkitt lymphoma and diffuse large B-cell lymphoma are cured with short intensive pulse chemotherapy containing cyclophosphamide, cytarabine, and high-dose methotrexate. The benefit of the addition of rituximab has not been established except in the case of primary mediastinal B-cell lymphoma. Lymphoblastic lymphoma is treated with intensive, semi-continuous, longer leukemia-derived protocols. Relapses in B-cell and lymphoblastic lymphomas are rare and infrequently curable, even with intensive approaches. Event-free survival rates of approximately 75% have been achieved in anaplastic large-cell lymphomas with various regimens that generally include a short intensive B-like regimen. Immunity seems to play an important role in prognosis and needs further exploration to determine its therapeutic application. ALK inhibitor therapeutic approaches are currently under investigation. For all pediatric lymphomas, the intensity of induction/consolidation therapy correlates with acute toxicities, but because of low cumulative doses of anthracyclines and alkylating agents, minimal or no long-term toxicity is expected. Challenges that remain include defining the value of prognostic factors, such as early response on positron emission tomography/computed tomography and minimal disseminated and residual disease, using new biologic technologies to improve risk stratification, and developing innovative therapies, both in the first-line setting and for relapse

Clinical characteristics and prognosis of osteosarcoma in young children: a retrospective series of 15 cases

<p>Abstract</p> <p>Background</p> <p>Osteosarcoma is the most common primary bone malignancy in childhood and adolescence. However, it is very rare in children under 5 years of age. Although studies in young children are limited in number, they all underline the high rate of amputation in this population, with conflicting results being recently reported regarding their prognosis.</p> <p>Methods</p> <p>To enhance knowledge on the clinical characteristics and prognosis of osteosarcoma in young children, we reviewed the medical records and histology of all children diagnosed with osteosarcoma before the age of five years and treated in SFCE (Société Française des Cancers et leucémies de l'Enfant) centers between 1980 and 2007.</p> <p>Results</p> <p>Fifteen patients from 7 centers were studied. Long bones were involved in 14 cases. Metastases were present at diagnosis in 40% of cases. The histologic type was osteoblastic in 74% of cases. Two patients had a relevant history. One child developed a second malignancy 13 years after osteosarcoma diagnosis.</p> <p>Thirteen children received preoperative chemotherapy including high-dose methotrexate, but only 36% had a good histologic response. Chemotherapy was well tolerated, apart from a case of severe late convulsive encephalopathy in a one-year-old infant. Limb salvage surgery was performed in six cases, with frequent mechanical and infectious complications and variable functional outcomes.</p> <p>Complete remission was obtained in 12 children, six of whom relapsed. With a median follow-up of 5 years, six patients were alive in remission, seven died of their disease (45%), in a broad range of 2 months to 8 years after diagnosis, two were lost to follow-up.</p> <p>Conclusions</p> <p>Osteosarcoma seems to be more aggressive in children under five years of age, and surgical management remains a challange.</p

R1507, an Anti-Insulin-Like Growth Factor-1 Receptor (IGF-1R) Antibody, and EWS/FLI-1 siRNA in Ewing's Sarcoma: Convergence at the IGF/IGFR/Akt Axis

A subset of patients with Ewing's sarcoma responds to anti-insulin-like growth factor-1 receptor (IGF-1R) antibodies. Mechanisms of sensitivity and resistance are unknown. We investigated whether an anti-IGF-1R antibody acts via a pathway that could also be suppressed by small interfering (si) RNA against the EWS/FLI-1 fusion protein, the hallmark of Ewing's sarcoma. The growth of two Ewing's sarcoma cell lines (TC-32 and TC-71) was inhibited by the fully human anti-IGF-1R antibody, R1507 (clonogenic and MTT assays). TC-32 and TC-71 cells express high levels of IGF-2, while RD-ES and A4573 Ewing's cell lines, which were less responsive to R1507 in our assays, express low or undetectable IGF-2, respectively. TC-71 cells also expressed high levels of IGF-1R, and R1507 decreased steady-state levels of this receptor by internalization/degradation, an effect which was associated with a decrease in p-IGF-1R, p-IRS-1, and p-Akt. EWS/FLI-1 siRNA also decreased p-Akt, due to its ability to increase IGF-BP3 levels and subsequently decrease IGF-1 and IGF-2 levels, thus inhibiting signaling through p-IGF-1R. This inhibition correlated with growth suppression and apoptosis. The attenuation of Akt activation was confirmed in TC-71 and HEK-293 (human embryonic kidney) cells by transfecting them with IGF-1R siRNA. We conclude that antibodies and siRNA to IGF-1R, as well as siRNA to EWS/FLI-1, act via intersecting IGF/IGF-1R signals that suppress a common point in this pathway, namely the phosphorylation of Akt

Pediatric T- and NK-cell lymphomas: new biologic insights and treatment strategies

T- and natural killer (NK)-cell lymphomas are challenging childhood neoplasms. These cancers have varying presentations, vast molecular heterogeneity, and several are quite unusual in the West, creating diagnostic challenges. Over 20 distinct T- and NK-cell neoplasms are recognized by the 2008 World Health Organization classification, demonstrating the diversity and potential complexity of these cases. In pediatric populations, selection of optimal therapy poses an additional quandary, as most of these malignancies have not been studied in large randomized clinical trials. Despite their rarity, exciting molecular discoveries are yielding insights into these clinicopathologic entities, improving the accuracy of our diagnoses of these cancers, and expanding our ability to effectively treat them, including the use of new targeted therapies. Here, we summarize this fascinating group of lymphomas, with particular attention to the three most common subtypes: T-lymphoblastic lymphoma, anaplastic large cell lymphoma, and peripheral T-cell lymphoma-not otherwise specified. We highlight recent findings regarding their molecular etiologies, new biologic markers, and cutting-edge therapeutic strategies applied to this intriguing class of neoplasms

Does chemotherapy-induced neutropaenia result in a postponement of adjuvant or neoadjuvant regimens in breast cancer patients? Results of a retrospective analysis

In 2005, 224 patients received adjuvant/neoadjuvant chemotherapy for breast cancer in a single institution according to daily practices. Regimens consisted of epirubicin-based chemotherapy (FEC100, four or six cycles), or three cycles of FEC100 followed by three cycles of docetaxel. An absolute blood count was carried out every 3 weeks, 1–3 days before planned chemotherapy cycle. Overall, 1238 cycles were delivered. An absolute neutrophil count (ANC) <1.5 × 109 l−1 before planned chemotherapy was found in 171 cycles. Of these, 130 cycles (76%) were delivered as planned regardless of whether ANC levels recovered, and 41 (24%) were delayed. None of these patients developed a febrile neutropaenia. Haematopoietic support (granulocyte colony-stimulating factor (G-CSF)) was required in 12 cycles. We found that the majority of patients with an ANC <1.5 × 109 l−1 before planned chemotherapy received planned doses, without complications and need for G-CSF