How Low Can We Go in Contrast-Enhanced CT Imaging of the Chest?: A Dose-Finding Cadaver Study Using the Model-based Iterative Image Reconstruction Approach.

RATIONALE AND OBJECTIVES: Dose reduction may compromise patients because of a decrease of image quality. Therefore, the amount of dose savings in new dose-reduction techniques needs to be thoroughly assessed. To avoid repeated studies in one patient, chest computed tomography (CT) scans with different dose levels were performed in corpses comparing model-based iterative reconstruction (MBIR) as a tool to enhance image quality with current standard full-dose imaging. MATERIALS AND METHODS: Twenty-five human cadavers were scanned (CT HD750) after contrast medium injection at different, decreasing dose levels D0-D5 and respectively reconstructed with MBIR. The data at full-dose level, D0, have been additionally reconstructed with standard adaptive statistical iterative reconstruction (ASIR), which represented the full-dose baseline reference (FDBR). Two radiologists independently compared image quality (IQ) in 3-mm multiplanar reformations for soft-tissue evaluation of D0-D5 to FDBR (-2, diagnostically inferior; -1, inferior; 0, equal; +1, superior; and +2, diagnostically superior). For statistical analysis, the intraclass correlation coefficient (ICC) and the Wilcoxon test were used. RESULTS: Mean CT dose index values (mGy) were as follows: D0/FDBR = 10.1 ± 1.7, D1 = 6.2 ± 2.8, D2 = 5.7 ± 2.7, D3 = 3.5 ± 1.9, D4 = 1.8 ± 1.0, and D5 = 0.9 ± 0.5. Mean IQ ratings were as follows: D0 = +1.8 ± 0.2, D1 = +1.5 ± 0.3, D2 = +1.1 ± 0.3, D3 = +0.7 ± 0.5, D4 = +0.1 ± 0.5, and D5 = -1.2 ± 0.5. All values demonstrated a significant difference to baseline (P < .05), except mean IQ for D4 (P = .61). ICC was 0.91. CONCLUSIONS: Compared to ASIR, MBIR allowed for a significant dose reduction of 82% without impairment of IQ. This resulted in a calculated mean effective dose below 1 mSv.

Fonctions du plancher pelvien: de la phase expulsive à la consultation du post-partum [Pelvic floor functions: from the beginning of the second phase of labor to the postpartum consultation].

Vaginal delivery can cause lesions of the various pelvic structures responsible for the mechanisms of continence. These lesions may perhaps be prevented in the future by measuring pressure generated during childbirth. Tear of the anal sphincter during childbirth is a marker of a global impairment of the urinary, ano-rectal and sexual pelvic functions in the short and medium term. Persistence of a defect of the anal sphincter is frequent in spite of immediate suture. The correlation between these defects and ano-rectal incontinence are not established in our experience. The quality of the contraction of the sphincter complex and pubo-rectal sling seems to play a more important role in ano-rectal continence after a traumatic childbirth.

Second cranio-facial malignancies in hereditary retinoblastoma survivors previously treated with radiation therapy: clinic and radiologic characteristics and survival outcomes.

INTRODUCTION: Hereditary retinoblastoma survivors have an increased risk for cranio-facial second primary tumours (SPT), especially after treatment with external beam radiotherapy (EBRT). This multicentre study evaluates the clinical and imaging characteristics and outcomes of cranio-facial SPTs in irradiated retinoblastoma survivors. PATIENTS AND METHODS: Clinical and radiological data of 42 hereditary retinoblastoma patients with 44 second and third malignancies were reviewed. Radiological data included anatomic location and computed tomography (CT) and magnetic resonance (MR) characteristics. Cox regression and likelihood ratio chi-square test were used to evaluate differences in patients' survival rates. RESULTS: Cranio-facial SPTs were diagnosed at a median age of 13 years. Histological types included osteosarcomas (43%), rhabdomyosarcomas (20%) (57% embryonal, 43% alveolar) and a variety of other types of SPT (37%). Predilection sites were: temporal fossa (39%), ethmoid sinus (23%), orbit (18%), maxillary sinus (16%) and intracranial dura mater (4%). Most of the osteosarcomas (78%) and rhabdomyosarcomas (80%) occurred in patients treated with EBRT in the first year-of-life. Treatment of SPTs with a microscopically complete surgical resection led to a significantly better 5-year overall survival (OS) (P=0.017) and event-free survival (EFS) (P=0.012) compared to patients treated without surgery or incomplete resection (OS: 83% versus 52%; EFS: 80% versus 47%). CONCLUSIONS: Osteosarcomas and rhabdomyosarcomas are the most common cranio-facial SPTs in irradiated hereditary retinoblastoma survivors, which develop in specific locations and occur predominantly in patients irradiated in their first year-of-life. Microscopically complete surgical resection of SPTs is a major prognostic factor, suggesting the potential benefit of early detection by imaging.

Playing Second Fiddle: Expert Advice and Decision-Making in Switzerland

This thesis concerns the role of scientific expertise in the decision-making process at the Swiss federal level of government. It aims to understand how institutional and issue-specific factors influence three things: the distribution of access to scientific expertise, its valuation by participants in policy for- mulation, and the consequence(s) its mobilization has on policy politics and design. The theoretical framework developed builds on the assumption that scientific expertise is a strategic resource. In order to effectively mobilize this resource, actors require financial and organizational resources, as well as the conviction that it can advance their instrumental interests within a particular action situation. Institutions of the political system allocate these financial and organizational resources, influence the supply of scientific expertise, and help shape the venue of its deployment. Issue structures, in turn, condition both interaction configurations and the way in which these are anticipated by actors. This affects the perceived utility of expertise mobilization, mediating its consequences. The findings of this study show that the ability to access and control scientific expertise is strongly concentrated in the hands of the federal administration. Civil society actors have weak capacities to mobilize it, and the autonomy of institutionalized advisory bodies is limited. Moreover, the production of scientific expertise is undergoing a process of professionalization which strengthens the position of the federal administration as the (main) mandating agent. Despite increased political polarization and less inclu- sive decision-making, scientific expertise remains anchored in the policy subsystem, rather than being used to legitimate policy through appeals to the wider population. Finally, the structure of a policy problem matters both for expertise mobilization and for the latter's impact on the policy process, be- cause it conditions conflict structures and their anticipation. Structured problems result in a greater overlap between the principal of expertise mobilization and its intended audience, thereby increasing the chance that expertise shapes policy design. Conversely, less structured problems, especially those that involve conflicts about values and goals, reduce the impact of expertise.

A study of the cambial zone and conductive phloem of common beech (Fagus sylvatica L.) using an image analysis method. I. Influence of tree age on the structure

Quantification is a major problem when using histology to study the influence of ecological factors on tree structure. This paper presents a method to prepare and to analyse transverse sections of cambial zone and of conductive phloem in bark samples. The following paper (II) presents the automated measurement procedure. Part I here describes and discusses the preparation method, and the influence of tree age on the observed structure. Highly contrasted images of samples extracted at breast height during dormancy were analysed with an automatic image analyser. Between three young (38 years) and three old (147 years) trees, age-related differences were identified by size and shape parameters, at both cell and tissue levels. In the cambial zone, older trees had larger and more rectangular fusiform initials. In the phloem, sieve tubes were also larger, but their shape did not change and the area for sap conduction was similar in both categories. Nevertheless, alterations were limited, and demanded statistical analysis to be identified and ascertained. The physiological implications of the structural changes are discussed.

Ultrasound-guided suprascapular nerve block, description of a novel supraclavicular approach.

BACKGROUND AND OBJECTIVES: The suprascapular nerve (SSN) block is frequently performed for different shoulder pain conditions and for perioperative and postoperative pain control after shoulder surgery. Blind and image-guided techniques have been described, all of which target the nerve within the supraspinous fossa or at the suprascapular notch. This classic target point is not always ideal when ultrasound (US) is used because it is located deep under the muscles, and hence the nerve is not always visible. Blocking the nerve in the supraclavicular region, where it passes underneath the omohyoid muscle, could be an attractive alternative. METHODS: In the first step, 60 volunteers were scanned with US, both in the supraclavicular and the classic target area. The visibility of the SSN in both regions was compared. In the second step, 20 needles were placed into or immediately next to the SSN in the supraclavicular region of 10 cadavers. The accuracy of needle placement was determined by injection of dye and following dissection. RESULTS: In the supraclavicular region of volunteers, the nerve was identified in 81% of examinations (95% confidence interval [CI], 74%-88%) and located at a median depth of 8 mm (interquartile range, 6-9 mm). Near the suprascapular notch (supraspinous fossa), the nerve was unambiguously identified in 36% of examinations (95% CI, 28%-44%) (P < 0.001) and located at a median depth of 35 mm (interquartile range, 31-38 mm; P < 0.001). In the cadaver investigation, the rate of correct needle placement of the supraclavicular approach was 95% (95% CI, 86%-100%). CONCLUSIONS: Visualization of the SSN with US is better in the supraclavicular region as compared with the supraspinous fossa. The anatomic dissections confirmed that our novel supraclavicular SSN block technique is accurate.

Trabecular Bone Score: A Noninvasive Analytical Method Based Upon the DXA Image.

The trabecular bone score (TBS) is a gray-level textural metric that can be extracted from the two-dimensional lumbar spine dual-energy X-ray absorptiometry (DXA) image. TBS is related to bone microarchitecture and provides skeletal information that is not captured from the standard bone mineral density (BMD) measurement. Based on experimental variograms of the projected DXA image, TBS has the potential to discern differences between DXA scans that show similar BMD measurements. An elevated TBS value correlates with better skeletal microstructure; a low TBS value correlates with weaker skeletal microstructure. Lumbar spine TBS has been evaluated in cross-sectional and longitudinal studies. The following conclusions are based upon publications reviewed in this article: 1) TBS gives lower values in postmenopausal women and in men with previous fragility fractures than their nonfractured counterparts; 2) TBS is complementary to data available by lumbar spine DXA measurements; 3) TBS results are lower in women who have sustained a fragility fracture but in whom DXA does not indicate osteoporosis or even osteopenia; 4) TBS predicts fracture risk as well as lumbar spine BMD measurements in postmenopausal women; 5) efficacious therapies for osteoporosis differ in the extent to which they influence the TBS; 6) TBS is associated with fracture risk in individuals with conditions related to reduced bone mass or bone quality. Based on these data, lumbar spine TBS holds promise as an emerging technology that could well become a valuable clinical tool in the diagnosis of osteoporosis and in fracture risk assessment. © 2014 American Society for Bone and Mineral Research.

High constant incidence rates of second primary cancers of the head and neck: a pooled analysis of 13 cancer registries.

Scanty data are available on the incidence (i.e., the absolute risk) of second cancers of the head and neck (HN) and its pattern with age. We investigated this issue using data from a multicentric study of 13 population-based cancer registries from Europe, Canada, Australia and Singapore for the years 1943-2000. A total of 99,257 patients had a first primary HN cancer (15,985 tongue, 22,378 mouth, 20,758 pharyngeal, and 40,190 laryngeal cancer), contributing to 489,855 person-years of follow-up. A total of 1,294 of the patients (1.3%) were diagnosed with second HN cancers (342 tongue, 345 mouth, 418 pharynx and 189 larynx). Male incidence rates of first HN cancer steeply increased from 0.68/100,000 at age 30-34 to 46.2/100,000 at age 70-74, and leveled off at older age; female incidence increased from 0.50/100,000 at age 30-34 to 16.5/100,000 at age 80-84. However, age-specific incidence of second HN cancers after a first HN cancer in men was around 200-300/100,000 between age 40-44 and age 70-74 and tended to decline at subsequent ages (150/100,000 at age 80-84); in women, incidence of second HN cancers was around 200-300/100,000 between age 45-49 and 80-84. The patterns of age-specific incidence were consistent for different subsites of second HN cancer and sexes; moreover, they were similar for age-specific incidence of first primary HN cancer in patients who subsequently developed a second HN cancer. The incidence of second HN cancers does not increase with age, but remains constant, or if anything, decreases with advancing age.

Is accurate perception of body image associated with appropriate weight-control behavior among adolescents of the Seychelles

BACKGROUND: We examined body image perception and its association with reported weight-control behavior among adolescents in the Seychelles.METHODS: We conducted a school-based survey of 1432 students aging 11-17 years in the Seychelles. Perception of body image was assessed using both a closed-ended question (CEQ) and Stunkard's pictorial silhouettes (SPS). Voluntary attempts to change weight were also assessed.RESULTS: A substantial proportion of the overweight students did not consider themselves as overweight (SPS: 24%, CEQ: 34%), and a substantial proportion of the normal-weight students considered themselves as too thin (SPS: 29%, CEQ: 15%). Logistic regression analysis showed that students with an accurate weight perception were more likely to have appropriate weight-control behavior.CONCLUSIONS: We found that substantial proportions of students had an inaccurate perception of their weight and that weight perception was associated with weight-control behavior. These findings point to forces that can drive the upwards overweight trends.

Neuropeptide-inducible upregulation of proteasome activity precedes nuclear factor kappa B activation in androgen-independent prostate cancer cells.

ABSTRACT: BACKGROUND: Upregulation of nuclear factor kappa B (NFκB) activity and neuroendocrine differentiation are two mechanisms known to be involved in prostate cancer (PC) progression to castration resistance. We have observed that major components of these pathways, including NFκB, proteasome, neutral endopeptidase (NEP) and endothelin 1 (ET-1), exhibit an inverse and mirror image pattern in androgen-dependent (AD) and -independent (AI) states in vitro. METHODS: We have now investigated for evidence of a direct mechanistic connection between these pathways with the use of immunocytochemistry (ICC), western blot analysis, electrophoretic mobility shift assay (EMSA) and proteasome activity assessment. RESULTS: Neuropeptide (NP) stimulation induced nuclear translocation of NFκB in a dose-dependent manner in AI cells, also evident as reduced total inhibitor κB (IκB) levels and increased DNA binding in EMSA. These effects were preceded by increased 20 S proteasome activity at lower doses and at earlier times and were at least partially reversed under conditions of NP deprivation induced by specific NP receptor inhibitors, as well as NFκB, IκB kinase (IKK) and proteasome inhibitors. AD cells showed no appreciable nuclear translocation upon NP stimulation, with less intense DNA binding signal on EMSA. CONCLUSIONS: Our results support evidence for a direct mechanistic connection between the NPs and NFκB/proteasome signaling pathways, with a distinct NP-induced profile in the more aggressive AI cancer state.

L'image de Paul dans les Actes des apôtres

(Résumé de l'ouvrage) Deuxième volet de l'oeuvre de Luc, le livre des Actes des Apôtres fait aujourd'hui l'objet de multiples travaux où se croisent enquêtes historiennes, analyses littéraires, questions théologiques. Pour son XXe congrès (Angers, août 2003), l'ACFEB a souhaité participer au débat. Ce volume en rassemble les contributions principales. Odile Flichy commence par dresser un panorama des recherches en cours : renouvellement de l'approche historique, lectures narratives, liens avec le judaïsme. Puis Roselyne Dupont-Roc reprend le problème de la double tradition textuelle du livre. Marie-Françoise Baslez situe le « monde des Actes » dans la littérature et la culture de l'époque. Jean-Pierre Lémonon, relisant Actes 18, 18 - 19, 7, examine les différents courants chrétiens qui marquent Éphèse au Ier siècle. Daniel Marguerat montre comment le récit de Luc dessine Paul comme une « figure identitaire » du christianisme. Michel Quesnel se risque à une analyse rhétorique des discours d'apologie de Paul (Ac 22 et 26). Rémi Gounelle débat des relations entre les foisonnants Actes apocryphes des Apôtres et les Actes des Apôtres canoniques. Enfin deux exemples de réception contemporaine du livre des Actes des Apôtres sont proposés : Laurent Villemin traite de son influence sur l'ecclésiologie du concile Vatican II et Carlos Mesters raconte la lecture qu'en font les « communautés ecclésiales de base » au Brésil. Au terme de ce parcours multiforme, les éditeurs n'ont qu'un souhait : que les lecteurs puissent, comme Théophile, « vérifier la solidité des enseignements [qu'ils ont] reçus » !

Heterogeneous secretion of individual B cells in response to D-glucose and to nonglucidic nutrient secretagogues.

We used a hemolytic plaque assay for insulin to determine whether the same pancreatic B cells respond to D-glucose, 2-amino-bicyclo[2,2,1]heptane-2-carboxylic acid (BCH) and the association of this nonmetabolized analogue of L-leucine with either the monomethyl ester of succinic acid (SME) or the dimethyl ester of L-glutamic acid (GME). During a 30-min incubation in the absence of D-glucose, BCH alone (5 mM) had no effect on insulin release. In contrast, the combination of BCH with either SME (10 mM) or GME (3 mM) stimulated insulin release to the same extent observed in the sole presence of 16.7 mM D-glucose. The effects of BCH plus SME and BCH plus GME on both percentage of secreting B cells and total insulin output were little affected in the presence of D-glucose concentrations ranging from 0 to 16.7 mM. Varying the concentration of SME from 2 to 10 mM also did not influence these effects. In other experiments, the very same B cells were first exposed 45 min to 16.7 mM D-glucose, then incubated 45 min in the presence of only BCH and SME. Under these conditions, most (80.3 +/- 2.5%) of the cells contributing to insulin release did so during both incubation periods. Furthermore, virtually all cells responding to BCH and SME during the second incubation corresponded to cells also responsive to D-glucose during the first incubation. Similar observations were made when the sequence of the two incubations was reversed.(ABSTRACT TRUNCATED AT 250 WORDS)

Survey on image quality and dose levels used in Europe for mammography.

Quality assurance programmes are becoming a common practice in the field of mammography. At the present time several recommendations exist and different test objects are used to optimize this radiological procedure. The goal of this study was to check if geographically distant centres using different quality control procedures were comparable when using a common objective way of assessing image quality. The results show that consensus still needs to be found among radiologists to reach a satisfactory level of harmony between patient doses and image quality in Europe.