Traumatologie de la personne âgée : une urgence nutritionnelle ? [Elderly orthopedic patients: Is nutritional support needed?]

La fracture de hanche chez la personne âgée reste un problème de santé publique. Elle est la conséquence d'une chute neuf fois sur dix et survient chez des personnes fragilisées par une ostéoporose, une sarcopénie, une dénutrition. Dans un service de traumatologie, la dénutrition protéino-énergétique est fréquente. Présente dès l'admission chez environ un patient sur deux, elle va souvent s'aggraver pendant le séjour hospitalier et favoriser la survenue de complications. Une prise en charge nutritionnelle doit impliquer une équipe multidisciplinaire qu'il faut coordonner. Elle doit être envisagée précocement pendant le séjour hospitalier et privilégier la voie orale. L'assistance nutritionnelle sous forme de CNO a prouvé son efficacité dans la réduction de la morbidité postopératoire. Son impact sur la mortalité, sur le pronostic fonctionnel et social reste discuté. Il faudra attendre l'étude de nouvelles cohortes dans lesquelles la compliance au traitement est nettement améliorée avant de conclure de manière définitive.

Web decoration of Micrathena sexpinosa (Araneae: Araneidae): a frame-web-choice experiment with stingless bees

The function of silk web decorations in orb weaving spiders has been debated for decades. The most accepted hypothesized functions are that web decorations I) provide camouflage against predators, 2) are an advertisement for vertebrates to avoid web damage, or 3) increase the attraction of prey to the web. Most studies have focused on only a few genera, Argiope being the most common. In this study, I evaluated the prey attraction hypothesis of silk decorations for a species of a poorly studied genus in this topic, Micrathena sexpinosa Hahn 1822. I used a web-choice experiment in which I presented empty or web-bearing frames at the end of a tunnel to stingless bees (Tetragonisca angustula). This frame-choice experiment consisted of the following comparisons: decorated web vs. empty frame, decorated web vs. undecorated web, and undecorated web vs. empty frame. Webs with decoration intercepted significantly more bees than empty frames and undecorated webs. Therefore, the decorations of Micrathena sexpinosa might play a role in increasing foraging success.

Induction of CD8 T-cell responses restricted to multiple HLA class I alleles in a cancer patient by immunization with a 20-mer NY-ESO-1f (NY-ESO-1 91-110) peptide.

Immunogenicity of a long 20-mer NY-ESO-1f peptide vaccine was evaluated in a lung cancer patient TK-f01, immunized with the peptide with Picibanil OK-432 and Montanide ISA-51. We showed that internalization of the peptide was necessary to present CD8 T-cell epitopes on APC, contrasting with the direct presentation of the short epitope. CD8 T-cell responses restricted to all five HLA class I alleles were induced in the patient after the peptide vaccination. Clonal analysis showed that B*35:01 and B*52:01-restricted CD8 T-cell responses were the two dominant responses. The minimal epitopes recognized by A*24:02, B*35:01, B*52:01 and C*12:02-restricted CD8 T-cell clones were defined and peptide/HLA tetramers were produced. NY-ESO-1 91-101 on A*24:02, NY-ESO-1 92-102 on B*35:01, NY-ESO-1 96-104 on B*52:01 and NY-ESO-1 96-104 on C*12:02 were new epitopes first defined in this study. Identification of the A*24:02 epitope is highly relevant for studying the Japanese population because of its high expression frequency (60%). High affinity CD8 T-cells recognizing tumor cells naturally expressing the epitopes and matched HLA were induced at a significant level. The findings suggest the usefulness of a long 20-mer NY-ESO-1f peptide harboring multiple CD8 T-cell epitopes as an NY-ESO-1 vaccine. Characterization of CD8 T-cell responses in immunomonitoring using peptide/HLA tetramers revealed that multiple CD8 T-cell responses comprised the dominant response.

Antagonistic effect of the inflammasome on thymic stromal lymphopoietin expression in the skin.

BACKGROUND: Innate immune sensors control key cytokines that regulate T-cell priming and T-cell fate. This is particularly evident in allergic reactions, which represent ideal systems to study the interplay of innate and adaptive immunity. In patients with contact dermatitis, inflammasome-mediated IL-1 activation is responsible for a TH1 immune response. Surprisingly, the IL-1 signaling pathway was also proposed to control the activation of thymic stromal lymphopoietin (TSLP), a cytokine implicated in development of the TH2 response in patients with atopic dermatitis (AD) and asthma. OBJECTIVES: We sought to assess the effect of the inflammasome on TSLP expression levels and the development of AD. METHODS: We studied the effect of the inflammasome activator 2,4-dinitrofluorobenzene, and IL-1β on TSLP mRNA expression levels in mouse and human cell lines (in vitro assays), as well as in live mice and on human skin transplants. We also assessed the effect of 2,4-dinitrofluorobenzene on TSLP and the TH2 response in mice in which the inflammasome and IL-1 signaling pathways were blocked, either genetically or pharmacologically, in 2 models of AD. RESULTS: We provide in vitro and in vivo evidence that inflammasome activation has an inhibitory role on TSLP mRNA expression and TH2 cell fate in the skin. We also show that solvents influence the activation of TSLP and IL-1β and direct the T-cell fate to a given hapten. CONCLUSION: Our observations strongly suggest that the TH1 versus TH2 cell fate decision is regulated at multiple levels and starts with innate immune events occurring within peripheral epithelial tissues.

Functional compensation of motor function in pre-symptomatic Huntington's disease.

Involuntary choreiform movements are a clinical hallmark of Huntington's disease. Studies in clinically affected patients suggest a shift of motor activations to parietal cortices in response to progressive neurodegeneration. Here, we studied pre-symptomatic gene carriers to examine the compensatory mechanisms that underlie the phenomenon of retained motor function in the presence of degenerative change. Fifteen pre-symptomatic gene carriers and 12 matched controls performed button presses paced by a metronome at either 0.5 or 2 Hz with four fingers of the right hand whilst being scanned with functional magnetic resonance imaging. Subjects pressed buttons either in the order of a previously learnt 10-item finger sequence, from left to right, or kept still. Error rates ranged from 2% to 7% in the pre-symptomatic gene carriers and from 0.5% to 4% in controls, depending on the condition. No significant difference in task performance was found between groups for any of the conditions. Activations in the supplementary motor area (SMA) and superior parietal lobe differed with gene status. Compared with healthy controls, gene carriers showed greater activations of left caudal SMA with all movement conditions. Activations correlated with increasing speed of movement were greater the closer the gene carriers were to estimated clinical diagnosis, defined by the onset of unequivocal motor signs. Activations associated with increased movement complexity (i.e. with the pre-learnt 10-item sequence) decreased in the rostral SMA with nearing diagnostic onset. The left superior parietal lobe showed reduced activation with increased movement complexity in gene carriers compared with controls, and in the right superior parietal lobe showed greater activations with all but the most demanding movements. We identified a complex pattern of motor compensation in pre-symptomatic gene carriers. The results show that preclinical compensation goes beyond a simple shift of activity from premotor to parietal regions involving multiple compensatory mechanisms in executive and cognitive motor areas. Critically, the pattern of motor compensation is flexible depending on the actual task demands on motor control.

Low adiponectin is associated with increased ambulatory pulse pressure and activation of the renin-angiotensin system in subjects of African descent

Purpose: Adiponectin, arterial stiffness, as well components of the renin-angiotensin system are associated with cardiovascular risk. This study was aimed to investigate whether plasma adiponectin was directly linked with pulse pressure (PP), as a marker for arterial stiffness, and the renin-angiotensin system (RAS). Methods and materials: A family-based study in subjects of African descent enriched with hypertensive patients was carried out in the Seychelles. Fasting plasma adiponectin was determined by ELISA, plasma renin activity according to the antibody-trapping principle and plasma aldosterone by radioimmunoassay. Daytime ambulatory blood pressure (BP) was measured using Diasys Integra devices. PP was calculated as the difference between systolic and diastolic BP. The association of adiponectin with PP, plasma renin activity and plasma aldosterone were analyzed using generalized estimating equations with a gaussian family link and an exchangeable correlation structure to account for familial aggregation. Results: Data from 335 subjects from 73 families (152 men, 183 women) were available. Men and women had mean (SD) age of 45.4 ± 11.1 and 47.3 ± 12.4 years, BMI of 26.3 ± 4.4 and 27.8 ± 5.1 kg/m2, daytime systolic/diastolic BP of 132.6 ± 15.4 / 86.1 ± 10.9 and 130 ± 17.6 / 83.4 ± 11.1 mmHg, and daytime PP of 46.5 ± 9.9 and 46.7 ± 10.7 mmHg, respectively. Plasma adiponectin was 4.4± 3.04 ng/ml in men and 7.39 ± 5.44 ng/ml in women (P <0.001). After adjustment for age, sex and BMI, log-transformed adiponectin was negatively associated with daytime PP (-0.009 ± 0.003, P = 0.004), plasma renin activity (-0.248 ± 0.080, P = 0.002) and plasma aldosterone (-0.004 ± 0.002, P = 0.014). Conclusion: Low adiponectin is associated with increased ambulatory PP and RAS activation in subjects of African descent. Our data are consistent with the observation that angiotensin II receptor blockers increase adiponectin in humans.

Identification of ectodysplasin target genes reveals the involvement of chemokines in hair development.

Ectodysplasin (Eda), a member of the tumor necrosis factor (Tnf) family, regulates skin appendage morphogenesis via its receptor Edar and transcription factor NF-κB. In humans, inactivating mutations in the Eda pathway components lead to hypohidrotic ectodermal dysplasia (HED), a syndrome characterized by sparse hair, tooth abnormalities, and defects in several cutaneous glands. A corresponding phenotype is observed in Eda-null mice, where failure in the initiation of the first wave of hair follicle development is a hallmark of HED pathogenesis. In an attempt to discover immediate target genes of the Eda/NF-κB pathway, we performed microarray profiling of genes differentially expressed in embryonic skin explants after a short exposure to recombinant Fc-Eda protein. Upregulated genes included components of the Wnt, fibroblast growth factor, transforming growth factor-β, Tnf, and epidermal growth factor families, indicating that Eda modulates multiple signaling pathways implicated in skin appendage development. Surprisingly, we identified two ligands of the chemokine receptor cxcR3, cxcl10 and cxcl11, as new hair-specific transcriptional targets of Eda. Deficiency in cxcR3 resulted in decreased primary hair follicle density but otherwise normal hair development, indicating that chemokine signaling influences the patterning of primary hair placodes only.

Basic life support teaching in the second year predraduate medical curriculum: quality of acquisition after 6 months

Purpose of the study: Basic life support (BLS) and automated externaldefibrillation (AED) represent important skills to be acquired duringpregraduate medical training. Since 3 years, our medical school hasintroduced a BLS-AED course (with certification) for all second yearmedical students. Few reports about quality and persistence over timeof BLS-AED learning are available to date in the medical literature.Comprehensive evaluation of students' acquired skills was performedat the end of the 2008 academic year, 6 month after certification.Materials and methods: The students (N = 142) were evaluated duringa 9 minutes «objective structured clinical examination» (OSCE) station.Out of a standardized scenario, they had to recognize a cardiac arrestsituation and start a resuscitation process. Their performance wererecorded on a PC using an Ambuman(TM) mannequin and the AmbuCPR software kit(TM) during a minimum of 8 cycles (30 compressions:2 ventilations each). BLS parameters were systematically checked. Nostudent-rater interactions were allowed during the whole evaluation.Results: Response of the victim was checked by 99% of the students(N = 140), 96% (N = 136) called for an ambulance and/or an AED. Openthe airway and check breathing were done by 96% (N = 137), 92% (N =132) gave 2 rescue breaths. Pulse was checked by 95% (N=135), 100%(N = 142) begun chest compression, 96% (N = 136) within 1 minute.Chest compression rate was 101 ± 18 per minute (mean ± SD), depthcompression 43 ± 8 mm, 97% (N = 138) respected a compressionventilationratio of 30:2.Conclusions: Quality of BLS skills acquisition is maintained during a6-month period after a BLS-AED certification. Main targets of 2005 AHAguidelines were well respected. This analysis represents one of thelargest evaluations of specific BLS teaching efficiency reported. Furtherfollow-up is needed to control the persistence of these skills during alonger time period and noteworthy at the end of the pregraduatemedical curriculum.

High constant incidence of second primary colorectal cancer.

Patients who had a colorectal cancer have a 1.5- to 2-fold excess risk of a second colorectal cancer as compared to the general population, the excess being higher at younger age at diagnosis. To further investigate the risk and the age-relation of the incidence of second primary colorectal cancer, we considered 9,389 first colon and rectal cancers registered in the Vaud Cancer Registry, Switzerland, between 1974 and 2008, and followed-up to the end of 2008 for a total of 44,113 person-years. There were 136 second colorectal cancers versus 90.5 expected, corresponding to a standardized incidence ratio (SIR) of 1.5 (95% confidence interval, CI, 1.3-1.8). The SIRs were not heterogeneous between men and women, and in strata of calendar year at diagnosis, duration of follow-up, and subsite. However, the SIR was 7.5 (95% CI 4.2-12.4) for subjects diagnosed below age 50 and declined thereafter to reach 1.0 (95% CI 0.6-1.6) at age 80 or over. Consequently, the incidence of second primary colorectal cancer was stable, and exceedingly high, around 300-400/100,000 between age 30-39 and 70 or over. This age pattern is consistent with the existence of a single mutational event in a population of highly susceptible individuals.

Auxin response factors ARF6 and ARF8 promote jasmonic acid production and flower maturation.

Pollination in flowering plants requires that anthers release pollen when the gynoecium is competent to support fertilization. We show that in Arabidopsis thaliana, two paralogous auxin response transcription factors, ARF6 and ARF8, regulate both stamen and gynoecium maturation. arf6 arf8 double-null mutant flowers arrested as infertile closed buds with short petals, short stamen filaments, undehisced anthers that did not release pollen and immature gynoecia. Numerous developmentally regulated genes failed to be induced. ARF6 and ARF8 thus coordinate the transition from immature to mature fertile flowers. Jasmonic acid (JA) measurements and JA feeding experiments showed that decreased jasmonate production caused the block in pollen release, but not the gynoecium arrest. The double mutant had altered auxin responsive gene expression. However, whole flower auxin levels did not change during flower maturation, suggesting that auxin might regulate flower maturation only under specific environmental conditions, or in localized organs or tissues of flowers. arf6 and arf8 single mutants and sesquimutants (homozygous for one mutation and heterozygous for the other) had delayed stamen development and decreased fecundity, indicating that ARF6 and ARF8 gene dosage affects timing of flower maturation quantitatively.

The adjective petit 'small, little' in French acquisition data: an example of the relationship between pragmatics and morphosyntactic development

In French the adjective petit 'small, little' has a special status: it fulfills various pragmatic functions in addition to semantic meanings and it is thus highly frequent in discourse. Résumé: This study, based on the data of two children, aged 1;6 to 2;11, argues that petit and its pragmatic meanings play a specific role in the acquisition of French adjectives. In contrast to what is expected in child language, petit favours the early development of a pattern of noun phrase with prenominal attributive adjective. The emergence and distribution of petit in the children's production is examined and related to its distribution in the input, and the detailed pragmatic meanings and functions of petit are analysed. Prenominal petit emerges early as the preferred and most productive adjective. Pragmatic meanings of petit appear to be predominant in this early age and are of two main types: expressions of endearment (in noun phrases) and mitigating devices whose scope is the entire utterance. These results, as well as instances of children's pragmatic overgeneralizations, provide new evidence that at least some pragmatic meanings are prior to semantic meanings in early acquisition.