Peripheral but not axial muscle mass is associated with early mortality in bone metastatic lung cancer patients at diagnosis

OBJECTIVES

Identification of sarcopenia is a key issue in oncology. Several methods may be used to evaluate muscle mass in patients. Routine cancer follow-up computed tomography (CT) provides axial muscle mass whereas whole-body densitometry (DEXA) measures appendicular lean mass (ALM). Up to now, no studies have assessed, in cancer patients, the correlation between CT and DEXA muscle mass indicators and compared their prognostic value.

METHODS

We included patients with synchronous bone metastases from lung adenocarcinoma at diagnosis. Diagnosis was confirmed by bone biopsy. Skeletal muscle area was determined semi-automatically on initial CT scan at the T7, T12, and L3 vertebral level using Osirix® software. The skeletal muscle index (SMI) was calculated as the ratio of muscle area to height squared. Standardised ALM/height squared data were obtained by DEXA assessment within a 30-day window of CT.

RESULTS

A total of 65 patients were included; 47 (72%) were male. Mean±SD age was 65±11.4years. DEXA was available for 46 patients. The performance status was good (<1) for 39 patients. SMI indicators were significantly correlated with each other (rho from 0.3 to 0.7) but moderately correlated with ALM (rho from 0.1 to 0.7). ALM had a good discriminatory ability on 6-month survival (AUC 0.87 [0.76; 0.97]). ALM was associated with early mortality (<6months) (HR=0.29, 95% CI [0.15; 0.57]; P<0.001) but not with later mortality (>6months). In contrast, no significant effect was found for SMI.

CONCLUSIONS

Peripheral muscle mass (standardized ALM by DEXA) but not axial muscle mass (SMI assessed by CT) was associated with early mortality (<6months) suggesting that cancer-induced muscle loss would affect differently appendicular muscles and axial muscles.

Unité mobile d’assistance circulatoire et respiratoire de l’enfant et du nouveau-né : une revue narrative

Les unités mobiles d’assistance circulatoire et respiratoire de l’enfant et du nouveau-né se sont développées au cours des dix dernières années. En effet, la mise en place d’une suppléance extracorporelle respiratoire ou circulatoire nécessite une équipe expérimentée et n’est pas disponible dans tous les centres hospitaliers pédiatriques. Or, les enfants atteints d’une défaillance circulatoire ou respiratoire réfractaire ne sont, pour la plupart, pas déplaçables vers une unité délivrant ce type de traitement de sauvetage. Les unités mobiles ont donc pour objectif de mettre à disposition ces technologies d’exception sur l’ensemble du territoire afin de garantir une égalité d’accès aux soins. Cependant, la haute technicité de ces thérapeutiques nécessite une équipe entraînée sachant poser et régler une assistance extracorporelle, prendre en charge un patient en défaillance respiratoire et/ou hémodynamique réfractaire et aguerrie à ces transports à haut risque. Le territoire français était jusqu’en 2014 très mal couvert par les unités mobiles pédiatriques et néonatales. Depuis, la création de plusieurs unités a permis une couverture totale du territoire. L’objectif de cette revue narrative sur les unités mobiles pédiatriques et néonatales est de résumer les différentes modalités de suppléance respiratoire et hémodynamique extracorporelle, d’en illustrer leurs différentes missions et leurs modalités de fonctionnement. Nous finirons par une description de leur efficacité en termes de survie et de survenue d’incidents en cours de transport.

Therapeutic approach to pediatric patients with acute chest syndrome: national multicenter survey of non invasive ventilation (NIV) and transfusion

BACKGROUND

Intensive care units (ICUs) have seen a spike in the use of noninvasive ventilation (NIV) for many medical conditions. We sought to investigate the attitudes and clinical practice regarding the management of acute chest syndrome (ACS) with a focus on NIV in pediatric ICUs.

METHOD

Members of the French Group for Pediatric Intensive Care Emergencies (GFRUP) were asked to complete an online survey on physicians' attitudes toward children with ACS admitted to the PICU during 2015.

RESULTS

The survey was answered by teams from 17 PICUs (240 beds). In total, 15 centers (88%) had a local transfusion unit and 14 (82%) worked in connection with a sickle cell disease (SCD) reference center. During 2015, 360 patients with SCD were managed (median: 7 per center; 21) of whom 137 (38%) for an ACS (median: 4 ACS per center; 8). The median length of PICU stay for ACS was 5 days (3.1). Among the 137 patients who presented with ACS, 73 (53%) received simple blood transfusion and 16 (12%) received exchange transfusion. For patients who required noninvasive ventilatory support, NIV with bilevel pressure (BiPAP) was the most frequent method (n = 68, 50%), followed by continuous positive airway pressure (CPAP) (n = 23, 17%) and high-flow oxygen (n = 21, 15%). The proportion of patients on BiPAP was up to 71% in the centers most frequently managing ACS patients.

CONCLUSION

BiPAP is commonly used in PICUs for SCD patients with ACS, especially in trained centers. Future physiological studies and randomized controlled trials might help to choose the best ventilatory support for ACS.

[Extracorporeal membrane oxygenation in critically ill neonates and children]

Extracorporeal membrane oxygenation is used as a last resort during neonatal and pediatric resuscitation in case of refractory circulatory or respiratory failure under maximum conventional therapies. Different types of ECMO can be used depending on the initial failure. The main indications for ECMO are refractory respiratory failure (acute respiratory distress syndrome, status asthmaticus, severe pneumonia, meconium aspiration syndrome, pulmonary hypertension) and refractory circulatory failure (cardiogenic shock, septic shock, refractory cardiac arrest). The main contraindications are a gestational age under 34 weeks or birth weight under 2kg, severe underlying pulmonary disease, severe immune deficiency, a neurodegenerative disease and hereditary disease of hemostasis. Neurological impairment can occur during ECMO (cranial hemorrhage, seizure or stroke). Nosocomial infections and acute kidney injury are also frequent complications of ECMO. The overall survival rate of ECMO is about 60 %. This survival rate can change depending on the initial disease: from 80 % for meconium aspiration syndrome to less than 10 % for out-of-hospital refractory cardiac arrest. Recently, mobile ECMO units have been created. These units are able to perform ECMO out of a referral center for untransportable critically ill patients.

A pilot study comparing two polymethylpentene extracorporeal membrane oxygenators

OBJECTIVE

We compared two polymethylpentene oxygenators being used in our unit: the Maquet Quadrox-iD paediatric and the Medos Hilite 800LT.

STUDY DESIGN

A mono-centric, prospective pilot study was conducted on ten consecutive newborn patients who had been admitted to our hospital service for extracorporeal circulation (EC) treatment. We examined the rate of oxygen transfer, the CO2 removal capacity and the average sweep gas flow required to produce this result. We also assessed the disturbances of haemostasis, the need for labile blood products and the membrane oxygenator lifetime and cost of use.

CONCLUSIONS

According to our study, it seems to us that Medos Hilite 800LT membrane oxygenators demonstrate greater oxygen transfer and CO2 removal capacity than Maquet Quadrox-iD paediatric membrane oxygenators, at a similar cost. These results lead us to conclude that it is reasonable to continue using Medos Hilite 800LT membrane oxygenators. A broader comparison study would be necessary in order to support these initial results.

Infrared, raman, and 13C NMR spectra of two crystalline forms of (1R,3S)-3-(p-thioanisoyl)-1,2,2-trimethylcyclopentanecarboxylic acid

A comparative structural analysis of the two polymorphic forms of (1R,3S)-3-(p-thioanisoyl)-1,2,2-trimethylcyclopentanecarboxylic acid has been performed with infrared, Raman, and 13C NMR spectroscopy. The results are compared with those of the crystallographic and thermal studies on the two forms published in previous papers. The enantiotropism of the polymorphs as well as the differences in the conformation of the carboxyl group and the resulting intermolecular hydrogen bonds were confirmed by the infrared and Raman studies.

Comparative study of the two polymorphic forms of p-(1R,3S) 3-thioanisoyl-1,2,2-trimethylcyclopentane carboxylic acid

The crystal structure of polymorph I of p-(1R,3S)3-thioanisoyl-1,2,2-trimethylcyclopentane carboxylic acid has been determined and is compared with that of polymorph II that was previously described. Polymorph I is very different at the level of the carboxyl group. It does not present disorder and the values found for the C-O bonds correspond exactly to single and double bond lengths. In addition, the carboxyl groups of the two molecules in the cell packing are involved in symmetric hydrogen bonds [2.662(6) A] leading to the formation of a dimer around the twofold axis following x with a shift on z. The different conformations on the carboxylic group between the two polymorphs are in good agreement with the thermodynamic study.

Crystal structure of the unique parvalbumin component from muscle of the leopard shark (Triakis semifasciata). The first X-ray study of an alpha-parvalbumin

The three-dimensional structure of parvalbumin from leopard shark (Triakis semifasciata) with 109 amino acid residues (alpha-series) is described at 1.54 A resolution. Crystals were grown at 20 degrees C from 2.9 M-potassium/sodium phosphate solutions at pH 5.6. The space group is P3(1)21 and unit cell dimensions are a = b = 32.12 A and c = 149.0 A. The structure has been solved by the molecular replacement method using pike 4.10 parvalbumin as a model. The final structure refinement resulted in an R-factor of 17.3% for 11,363 independent reflections at 1.54 A resolution. The shark parvalbumin shows the main features of all parvalbumins: the folding of the chain including six alpha-helices, the salt bridge between Arg75 and Glu81, and the hydrophobic core. Compared to the structure of beta-parvalbumins from pike and carp, one main difference is observed: the chain is one residue longer and this additional residue, which extends the F helix, is involved through its C-terminal carboxylate group in a network of electrostatic contacts with two basic residues, His31 in the B helix and Lys36 in the BC segment. Furthermore, hydrogen bonds exist between the side-chains of Gln108 (F helix) and Tyr26 (B helix). There is therefore a "locking" of the tertiary structure through contacts between two sequentially distant regions in the protein and this is likely to contribute to making the stability of an alpha-parvalbumin higher in comparison to that of a beta-parvalbumin. The lengthening of the C-terminal F helix by one residue appears to be a major feature of alpha-parvalbumins in general, owing to the homologies of the amino acid sequences. Besides the lengthening of the C-terminal helix, the classification of the leopard shark parvalbumin in the alpha-series rests upon the observation of Lys13, Leu32, Glu61 and Val66. As this is the first crystal structure description of a parvalbumin from the alpha-phylogenetic lineage, it was hoped that it would clearly determine the presence or absence of a third cation binding site in parvalbumins belonging to the alpha-lineage. In beta-pike pI 4.10 parvalbumin, Asp61 participates as a direct ligand of a third site, the satellite of the CD site. In shark parvalbumin, as in nearly all alpha-parvalbumins, one finds Glu at position 61. Unfortunately, the conformation of the polar head of Glu61 cannot be inferred from the X-ray data.(ABSTRACT TRUNCATED AT 400 WORDS)

Ionic interactions with parvalbumins. Crystal structure determination of pike 4.10 parvalbumin in four different ionic environments

The crystal structure of the Ca-loaded form of pike 4.10 parvalbumin (minor component from pike muscle belonging to the beta phylogenetic series), with both its primary sites CD and EF occupied by Ca2+ ions and its third site occupied by an ammonium ion, as previously determined at 1.93 A resolution, has now been refined to a resolution of 1.65 A. The crystallization of this parvalbumin in different ionic environments has allowed three novel non-isomorphous crystalline forms to be obtained: (1) a first form, crystallized in the presence of a mixture of ammonium sulphate and manganese sulphate, for which all the cation binding sites in the protein are occupied by Mn2+; (2) a second form crystallized in the presence of MgSO4 as the precipitating agent, only differs from the Ca/NH4 form by the occupation of the third site by Mg2+, whereas the primary sites remain occupied by Ca2+; (3) a third form, also crystallized in the presence of MgSO4, corresponds to a well-defined molecular species with both the primary EF site and the third site occupied by Mg2+, whereas the primary CD site remains occupied by CA2+. The corresponding molecular structures reported here have been determined at resolutions between 1.8 and 2.4 A. The comparison of the different crystal structures allows the structural modifications accompanying the substitution of the primary sites by cations differing significantly in their ionic radii (Ca2+, Mn2+, Mg2+) to be investigated in detail, and it also leads to a precise description of the third site in a typical beta parvalbumin. The substitution Ca2+ by Mg2+ within the primary site EF is characterized by a "contraction" of the co-ordination sphere, with a decrease of the mean oxygen-metal distance by a value of 0.25 A and a decrease of the co-ordination number from 7 to 6, as a consequence of the loss of a bidentate ligand (Glu101), which becomes a monodentate one. Such an adaptation of the co-ordination sphere around a cation of smaller size involves, among others, the transformation of the Glu101 side-chain from the stable gauche(+) form to the less stable gauche(-) form. The third site is clearly described as a satellite of the CD primary site, since both sites possess common protein ligands, such as Asp53 and Glu59. Furthermore, Asp61 appears as a specific ligand of the third site in the different environments investigated in this work. We finally discuss the relevance of the third site to parvalbumin phylogeny.

[Spectral and thermal characterization of cephalosporins. I. Cefadroxil and cefalexin]

Cefadroxil and cefalexine were characterized by thermal and spectral analysis. A vibrational study by infrared and Raman spectroscopies was made to connect the structural data with the antibacterial activity.

Gastric form of alpha chain disease

A case of alpha chain disease, involving the stomach only, is reported in an Algerian man suffering from epigastric pains. Upper digestive tract fibreoptic endoscopy showed two antral ulcers and an ulcerative gastritis pattern, which promptly disappeared with cimetidine treatment. Antral biopsies at a distance from the ulcers, but not of the ulcer crater itself, disclosed a dense infiltration of antral lamina propria by mature or sometimes atypical plasma cells. On transmural surgical antral biopsy, the infiltrate spread to the superficial part of the submucosa. No other localisation of the disease was found in spite of multiple biopsies obtained by endoscopy, with a peroral capsule and during staging laparotomy. The alpha chain disease protein was absent from serum and urine, but found in the gastric juice and in the cytoplasma of the cellular infiltrate (alpha 1 subclass). A complete clinical, endoscopic, histological and immunological remission was observed after a six months' course of oral tetracycline.

Physicochemical and structural study of sulfamethazine

We have shown by several physicochemical methods that the existence of different crystal habits for a given molecule does not necessarily imply polymorphism. For sulfamethazine, we found one polymorph, form 1, whose crystalline structure is published herein, and a methanol solvate.

Cholestasis as a paraneoplastic manifestation of carcinoma of the kidney

Two cases of hepatic paraneoplastic manifestations of carcinoma of the kidney are presented. In one, hepatosplenomegaly and abnormal liver function tests resolved following removal of the tumour. In the other, pruritus as a symptom of cholestasis was the presenting feature. Post-operatively a full blown cholestatic syndrome developed. Although their clinical presentations differed they may represent a spectrum of the same disease.

[Chronic inflammatory neuromyopathies in adults treated for gluten-sensitive enteropathy. A report on three cases with microvascular nerve and muscle lesions (author's transl)]

Neuromyopathies developed in three patients with gluten-sensitive enteropathy, a long time after they had been cured of their digestive disease by following a gluten-free diet. These cases differed radically from typical deficiency neuropathies by the presence of microvascular inflammatory lesions in nerves and muscles. The semiological findings were similar in all 3 cases, and were distinguished by the association of signs eveking lesions of the largest myelinated nerves fibers to the posterior rami with lesions in the muscles. Corticotherapy improved the condition but did not affect its chronic course. Nerve and muscle biopsies revealed the presence of segmentary microrascularitis, mainly lymphohistiocytic. The probable mechanism of these histological changes is alterations in the circulating immune-complexes, usually found in gluten-sensitive enteropathy, producing various types of associated disorders. Some of these immune-complexes would not be related straight to digestive intolerance to gluten, but would persist during the gluten-free diet period, and could be responsible for the micro-angiitis.