Radiologic diagnosis of Erdheim-Chester disease. A case report

Erdheim-Chester disease is a rare disorder, belonging to the group of histiocytoses, in which diffuse infiltration of histiocytes affects various organs and systems. Bone involvement in Erdheim-Chester disease manifests as generalized sclerosis of the bone marrow and cortex of the long bones, and this peculiar radiologic characteristic differentiates it from other histiocytoses. Diagnostic suspicion of the disease derives from the pulmonary and bone radiologic findings as well as from the clinical findings. Histological study reveals histiocyte infiltration affecting the soft tissues, musculoskeletal system, and central nervous system. The definitive diagnosis is reached by immunohistochemistry. Like other histiocytoses, such as Langerhans cell histiocytosis, immunohistochemical techniques reveal lipid-laden histiocytes; however, unlike the other types, Erdheim-Chester histiocytes stain negatively for S 100 protein and do not contain Birbeck granules.     

Evolución de la enfermedad neumocócica invasora y sus serotipos en la Comunidad de Madrid

Introduction

Streptococcus pneumoniae is an important cause of morbidity. Vaccination is the most effective measure to prevent it. The aim of this study is to analyse the evolution of invasive pneumococcal disease (IPD).

The genome of melon (Cucumis melo L.)

We report the genome sequence of melon, an important horticultural crop worldwide. We assembled 375 Mb of the double-haploid line DHL92, representing 83.3% of the estimated melon genome. We predicted 27,427 protein-coding genes, which we analyzed by reconstructing 22,218 phylogenetic trees, allowing mapping of the orthology and paralogy relationships of sequenced plant genomes. We observed the absence of recent whole-genome duplications in the melon lineage since the ancient eudicot triplication, and our data suggest that transposon amplification may in part explain the increased size of the melon genome compared with the close relative cucumber. A low number of nucleotide-binding site-leucine-rich repeat disease resistance genes were annotated, suggesting the existence of specific defense mechanisms in this species. The DHL92 genome was compared with that of its parental lines allowing the quantification of sequence variability in the species. The use of the genome sequence in future investigations will facilitate the understanding of evolution of cucurbits and the improvement of breeding strategies.     

Biological and structural effects after intraosseous infiltrations of age-dependent platelet-rich plasma: An in vivo study

Platelet-rich plasma (PRP) is an increasingly widespread treatment for joint pathologies. Its characteristics and administration route are variables that may influence the clinical outcome. The aim of this in vivo study was to analyze in aged rats the biological and structure effects of intraosseous infiltrations of two different types of PRP obtained from young and old donors. During 6 months intraosseous infiltrations were performed and 4 days after the last infiltration, animals were sacrificed, and bones were extracted for micro-computed tomography (micro-CT) and histological analysis. Molecular composition of the PRP of aged donors presented higher levels of proinflammatory molecules. The histological studies showed a greater cellularity of bone marrow in groups treated with PRP. Concerning micro-CT analysis, young PRP showed a better femoral bone structure according to values of percentage of trabecular bone, trabecular space, trabecular density, and subchondral bone plate volume. In summary, this study has demonstrated that intraosseous infiltrations of PRP from young donors prevent from age-related bone degeneration. This treatment could stimulate the biological processes that maintain homeostasis and bone structure and avoid osteoarticular pathologies.     

Effect of Dynamic Recrystallization on Microstructural Evolution in B Steels Microalloyed with Nb and/or Mo

The dynamic recrystallization behavior of ultra-high strength boron-microalloyed steels optionally alloyed with niobium and molybdenum is analyzed in this paper. Multipass torsion tests were performed to simulate plate rolling conditions followed by direct quenching. The influence of alloy composition on the transformed microstructure was evaluated by means of EBSD, thereby characterizing the morphology of the austenite grain morphology after roughing and finishing passes. The results indicated that for Nb-microalloyed steel, partial dynamic recrystallization occurred and resulted in local clusters of fine-sized equiaxed grains dispersed within the pancaked austenitic structure. A recrystallized austenite fraction appeared and transformed into softer phase constituents after direct quenching. The addition of Mo was shown to be an effective means of suppressing dynamic recrystallization. This effect of molybdenum in addition to its established hardenability effects hence safeguards the formation of fully martensitic microstructures, particularly in direct quenching processes. Additionally, the circumstances initiating dynamic recrystallization were studied in more detail, and the interference of the various alloying elements with the observed phenomena and the potential consequences of dynamic recrystallization before quenching are discussed.     

Atypical aquagenic keratoderma

Aquagenic keratoderma is an infrequent condition characterized by the appearance of lesions on the palms of the hands a few minutes after contact with water; these lesions vanish a short time after they dry. Published cases were primarily in adolescent females. We present the case of a male patient with lesions that clinically corresponded to aquagenic keratoderma, except that they were distributed on the backs of both hands and on the anterior face of the wrist. These characteristics had not been described in the literature prior to this case. Previously described cases were reviewed and several differential diagnoses were established, such as rofecoxib-induced palmar lesions, or those appearing in cystic fibrosis.     

Physiological Responses during Cycling With Oval Chainrings (Q-Ring) and Circular Chainrings

The aim of this study was to compare the physiological responses of cyclists using round (C-ring) or oval (Q-ring) chainrings during an incremental test until exhaustion. Following a randomized design, twelve male elite cyclists [age (mean ± SD): 21.1 ± 2.1 yr; VO_2max: 78.1 ± 5.3 mL·kg^-1min^-1] performed two incremental maximal tests separated by 48 h (one with C-rings, the other with Q-rings). Starting at 100 W, the workload was increased by 25 W every 3 min until volitional exhaustion. Maximal heart rate, power output and oxygen consumption were compared. Blood lactate was monitored throughout the test. After the incremental test, 4 intermittent 20-s maximal sprints with a 60-s recovery period in between were performed. Maximal isometric voluntary contractions were performed at rest and immediately after each 20-s maximal sprint, and the force and EMG RMS amplitude were recorded from the vastus medialis and vastus lateralis muscles. For the incremental exercise test, no significant differences were found in the maximal power output (P=0.12), oxygen consumption (P=0.39), and heart rate (P=0.32) between Q-rings and C-rings. Throughout the incremental test, lactate levels were comparable when using both the C-rings and Q-rings (P=0.47). During the short sprints, power output was 2.5–6.5% greater for Q-rings than for C-rings (P=0.22). The decline in EMG RMS amplitude observed during the incremental tests was comparable for Q-rings and C-rings (0.42). These findings indicate that the oval chainring design, presented here as “Q-rings”, did not significantly influence the physiological response to an incremental exercise test as compared to a conventional chainring.

Key points

• During the incremental exercise test, no significant differences were found in power output, oxygen consumption or heart rate between oval “Q-rings” and conventional chainrings.
• Over the course of the incremental test, blood lactate levels were comparable for the oval “Q-rings” and conventional chainrings.
• During the short sprints performed after the incremental test, there were no statistical differences in power production between oval “Q-rings” and conventional chainrings.

Key Words: Pedaling, chainring, blood lactate, fatigue, biomechanics