Clofarabine monotherapy in aggressive, relapsed and refractory Langerhans cell histiocytosis

Over 50% of patients with systemic LCH are not cured with front-line therapies, and data to guide salvage options are limited. We describe 58 patients with LCH who were treated with clofarabine. Clofarabine monotherapy was active against LCH in this cohort, including heavily pretreated patients with a systemic objective response rate of 92.6%, higher in children (93.8%) than adults (83.3%). BRAFV600E+ variant allele frequency in peripheral blood is correlated with clinical responses. Prospective multicentre trials are warranted to determine optimal dosing, long-term efficacy, late toxicities, relative cost and patient-reported outcomes of clofarabine compared to alternative LCH salvage therapy strategies.

Activation of the mitogen-activated protein kinase-extracellular signal-regulated kinase pathway in childhood B-cell acute lymphoblastic leukemia

RAS mutations are frequently observed in childhood B-cell acute lymphoblastic leukemia (B-ALL) and previous studies have yielded conflicting results as to whether they are associated with a poor outcome. We and others have demonstrated that the mitogen-activated protein kinase-extracellular signal-regulated kinase (MAPK) pathway can be activated through epigenetic mechanisms in the absence of RAS pathway mutations. Herein, we examined whether MAPK activation, as determined by measuring phosphorylated extracellular signal-regulated kinase (pERK) levels in 80 diagnostic patient samples using phosphoflow cytometry, could be used as a prognostic biomarker for pediatric B-ALL. The mean fluorescence intensity of pERK (MFI) was measured at baseline and after exogenous stimulation with or without pretreatment with the mitogen-activated protein kinase kinase (MEK) inhibitor trametinib. Activation levels (MFI stimulated/MFI baseline) ranged from 0.76 to 4.40 (median = 1.26), and inhibition indexes (MFI stimulated/MFI trametinib stimulated) ranged from 0.439 to 5.640 (median = 1.30), with no significant difference between patients with wildtype versus mutant RAS for either. Logistic regression demonstrated that neither MAPK activation levels nor RAS mutation status at diagnosis alone or in combination was prognostic of outcome. However, 35% of RAS wildtype samples showed MAPK inhibition indexes greater than the median, thus raising the possibility that therapeutic strategies to inhibit MAPK activation may not be restricted to patients whose blasts display Ras pathway defects.

Acute myeloid leukemia with an MN1-ETV6 fusion in a young child with Down syndrome

Myeloid leukemia of Down syndrome (ML-DS) in young children is associated with distinct clinical and biological features and is typically initiated with oncogenic mutations in the X-linked megakaryocytic transcription factor GATA1. Here we present a 3-yr-old child with DS diagnosed with acute myeloid leukemia (AML), which lacks typical immunophenotypic and molecular characteristics of ML-DS, including GATA1 mutations. The leukemic blasts were found to have an MN1-ETV6 gene fusion, a high-risk oncofusion not previously described in DS patients. This report highlights the importance of immunophenotypic, cytogenetic, and molecular characterization of ML-DS for identification of rare cases with unique features that may benefit from treatment protocols that are more intensive than those developed for patients with typical GATA1 mutant ML-DS.

Morphology and molecular phylogeny of Macrobrachium snpurii, a new species of the genus Macrobrachium Bate, 1868 from Kerala, India

Macrobrachium snpurii sp. nov., collected from the Karamana River, in the lower reaches of Western Ghats, is described and illustrated. DNA barcoding using Cytochrome B gene sequences has elucidated the taxonomic status of the new species and the NJ tree reveals that M. snpurii sp. nov., is phylogenetically close to M. idella idella. However, morphometric and meristic features of the species share certain characters with M. idella idella, M. patheinense and M. tratense, while it diverges remarkably from these three species in distinctive diagnostic characters: rostral formula 12-14/4 with 2 postorbital teeth; carapace smooth with distal end of rostrum directed upwards; chelae with 2 proximal denticles both in the movable and immovable fingers. A wide gap present in the distal part of the chelae, when fingers are closed. Movable finger, longer than the immovable and distal end of fingers inwardly hook-like; palm more pigmented than fingers and telson extends beyond the level of the outer lateral spine of uropodal exopod. A pair of plumose setae is present between the inner pair of movable spines of telson.

Macrobrachium indianum (Decapoda: Palaemonidae), a new species of hill stream prawn from Pambar River, Kerala, India

Macrobrachium indianum new species is described from the Pambar River, Kerala, S. India. The species shares certain characters with M. gurudeve Jayachandran & Raji, 2004, M. bombayense Almelker & Sankolli, 2006 and M. kulkarnii Almelker & Sankolli, 2006, while it differs remarkably from these three species in distinctive diagnostic characters: rostral formula 7-8/3-4 with 1 postorbital teeth, one tooth above orbit; carapace smooth with distal end of rostrum directed downwards; cephalothorax longer than rostrum; in second chelate leg, proximal cutting edge of movable finger with two weak denticles, one weak denticle in immovable finger, carpus longer than merus, merus shorter than propodus and longer than ischium; dactylus the shortest podomere. Five thick and a few thin reddish brown bands of chromatophores are seen on carapace. Pigmentation is found mid and ventro-laterally on abdominal segments, pereiopods have chromatophores at the distal part of podomeres.

Description, DNA barcode and phylogeny of a new species, Macrobrachium abrahami (Decapoda: Palaemonidae) from Kerala, India

Macrobrachium abrahami, new species is described from Vamanapuram River, Kerala, South India. DNA bar-coding using Cytochrome B gene sequences has elucidated the taxonomic status of the new species and the ML tree reveals that M. abrahami sp. nov., is phylogenetically close to M. prabhakarani, but morphologically more similar to M. scabriculum. However, the species shares certain morphological characters with M. scabriculum, M. prabhakarani and M. lanatum, but differs remarkably from these three species in distinctive diagnostic characters: rostrum moderately long, convex, distal end directed upwards, rostral formula 12-15/2-3 with 5-6 postorbital teeth, and carapace glabrous. In larger second chelate leg, fingers stout, pubescence restricted to their base; proximal half of cutting edge with fifteen denticles. In smaller second chelate leg, cutting edge of both fingers carry six small denticles situated proximally, distal one comparatively larger. Delicate setae are seen throughout the palm. A row of dark chromatophores is present along the posterio-dorsal margin of uropodal exopods and endopods, close to the base of uropodal setae. The thickness of each band of the row is almost equal to the thickness of uropodal setae.

Deposition and clearance of 212Pb in humans

Radiation exposure due to the inhalation of 212Pb has been identified as one of the major hazards encountered in the chemical processing of monazite. Volunteers were exposed to 212Pb in the thorium hydroxide storage facility. Personal air samplers were used to determine the concentration of 212Pb in air. The 212Pb in the chest was measured using a whole body counter and the decay in the chest was followed up for 24 h. From the decay, mean effective half-life for the inhaled 212Pb was estimated as 6.63 +/- 0.23 h. A comparison of the chest burden with the assumed intake indicates that 55-76% of the inhaled 212Pb is deposited in the respiratory system. From the chest monitoring data, it is possible to estimate the working level exposure due to thoron progeny.

Identical twins with identical vesicoureteric reflux: chronic pyelonephritis in one

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