Impact of malnutrition on survival and infections among pediatric patients with cancer: a retrospective study.

OBJECTIVE: Recognizing and managing malnutrition among hospitalized children affected by cancer is a rising need. Awareness and consideration of malnutrition among clinicians are still largely insufficient. This can principally be explained by the lack of consciousness and the shortage of easy and objective tools to identify malnutrition status. The aim of this study is to explore the impact of malnutrition on survival and infections among a population of pediatric patients with cancer. PATIENTS AND METHODS: All children aged between 3 and 18 years, newly diagnosed with a malignancy between August 2013 and April 2018, were included in our study. We assessed nutritional risk at diagnosis (with STRONGkids), then we evaluated anthropometric measurements (BMI Z-scores and weight loss), data about survival and number of hospitalization for febrile neutropenia (FN) in the first year after diagnosis. Cut-off values for malnourishment were chosen as BMI Z-score ≤-2.0. RESULTS: One hundred twenty-six pediatric cancer patients were included in the study. At diagnosis 36 pediatric cancer patients (28.6%) were at high risk of malnutrition (STRONGkids 4 or 5), whereas 6 (4.7%) others were malnourished (BMI Z-score≤-2.0). The risk of mortality and the rate of infections (≥3 hospitalizations for FN episodes) were significantly increased by malnutrition and rapid weight loss in the initial phase of treatment (3-6 months after diagnosis). Multivariate analysis confirmed the independent effect of weight loss≥ 5% at 3 months on both survival and infections, and the independent impact of a high risk of malnutrition at diagnosis on infections. CONCLUSIONS: A personalized evaluation of nutritional risk at diagnosis and a close monitoring of nutritional status during the initial phase of treatment are crucial for ensuring a timely and personalized nutritional intervention, which may potentially improve tolerance to chemotherapy and survival, and prevent prolonged hospitalization for infections in childhood cancer patients.

Biochemical purification and crystallographic characterization of the fiber-forming protein pilin from Neisseria gonorrhoeae.

Pilus fibers are long protein filaments on many pathogenic bacteria that participate in attachment to host cells. Although the self-assembling protein pilin is the major structural component of the Neisseria gonorrhoeae pilus fiber, several other proteins co-purified with pilin through the repeated solubilization-reassociation steps of the biochemical purification. Pilin solubilized in the nondenaturing detergent n-octyl-beta-D-glucopyranoside remained an aggregate of about 100 kDa at pH 9.5, but was reduced to a 40-kDa dimer at pH 10.5, suggesting that assembly involves electrostatic interactions of lysine, tyrosine, or other side chains with high pKa values. Pilin dimers and aggregates of higher molecular mass were partially stable even in the presence of sodium dodecyl sulfate and beta-mercaptoethanol. Removal of pilus-associated proteins and stabilization of pilin multimers permitted the reproducible crystallization of pilin. Three-dimensional needle- and plate-shaped crystals of purified N. gonorrhoeae pilin (strain MS11 variant C30) grew from 36 to 40% polyethylene glycol 400, pH 8.0-9.0, in space group C222, with cell dimensions a = 126.4, b = 121.2, c = 26.7 A and Vm = 2.84 A3/dalton for one molecule per asymmetric unit. The best crystals diffracted to 2.4 A resolution using synchrotron radiation, were stable to x-ray damage, and appear suitable for determination of the atomic structure. This approach of stabilizing and crystallizing an intermediate assembly state may be useful for other fiber-forming proteins, which have previously not been successfully crystallized in forms that diffract to atomic resolution.

Estrogen differentially regulates neuropeptide gene expression in a sexually dimorphic olfactory pathway.

The posterodorsal part of the medial nucleus of the amygdala (MeAp) receives its major sensory input from the accessory olfactory bulb and projects massively to the medial preoptic nucleus and other sexually dimorphic hypothalamic nuclei thought to play key roles in mediating steroid-sensitive reproductive functions. A combined axonal transport/double-immunohistochemical method was used to show that at least one-quarter of the cholecystokinin-immunoreactive cells in the MeAp cocontain substance P and that a substantial proportion of these cells project to the medial preoptic nucleus. In situ hybridization histochemistry was then used to demonstrate that estrogen regulates the expression of preprocholecystokinin in these cells at the mRNA level in male and female rats. In contrast, levels of preprotachykinin mRNA within the MeAp do not appear to be sensitive to acute changes in circulating gonadal steroids in either sex. Although posttranscriptional regulation of mRNA stability may contribute to the observed effects, it appears likely that estrogen stimulates preprocholecystokinin expression within the MeAp by selectively inducing transcription of the corresponding gene, thereby altering the relative amounts of cholecystokinin and substance P coexpressed within individual neurons of the MeAp that project to the hypothalamus.

Differential expression of type-specific c-abl mRNAs in mouse tissues and cell lines.

The mammalian c-abl proto-oncogene produces mRNAs with 5' heterogeneity from two distinct promoters and the alternative splicing of variable 5' exons. By using quantitative RNase protection assays, the relative abundance of two major c-abl mRNAs, type I and type IV, in several mouse tissues and cell lines has been determined. Our results demonstrate that the level of type IV c-abl mRNA is rather constant, whereas that of the type I mRNA varies over a 10-fold range in different tissues and cell types. This finding has interesting implications for the function of the two c-abl proteins.

Three dimensional structure of bacterial pili.

Crystallographic and associated biochemical and structural studies are in progress on the fiber-forming pilin proteins of the gonococcal pilus. Preparative scale purification procedures have been developed for the gonococcal pilin protein, which appear generally applicable to bacterial pilins. For three gonococcal pilin protein strains, we have obtained both reassembled pilus fibers and three-dimensional crystals. One needle-shaped crystal form of gonococcal C30 pilin diffracts beyond 3 A resolution using synchrotron x-ray radiation. A diffraction data set to 3.5 A resolution has been collected on these needle-shaped crystals (lattice spacings a = 125.4(3) b = 120.4(3), c = 26.61(4) A) in which the packing arrangement of the pilin subunits appears to resemble that seen in the pilus fibers using electron microscopy. X-ray diffraction data confirm our proposed model for the overall polypeptide fold of a pilin subunit, which is an antiparallel 4-alpha helix bundle similar to tobacco mosaic virus coat protein and myohemerythrin.