A flexible design framework to design graded porous bone scaffolds with adjustable anisotropic properties.

Since the success of bone regenerative medicine depends on scaffold morphological and mechanical properties, numerous scaffolds designs have been proposed in the last decade, including graded structures that are suited to enhance tissue ingrowth. Most of these structures are based either on foams with a random pore definition, or on the periodic repetition of a unit cell (UC). These approaches are limited by the range of target porosities and obtained effective mechanical properties, and do not permit to easily generate a pore size gradient from the core to the periphery of the scaffold. In opposition, the objective of the present contribution is to propose a flexible design framework to generate various three-dimensional (3D) scaffolds structures including cylindrical graded scaffolds from the definition of a UC by making use of a non-periodic mapping. Conformal mappings are firstly used to generate graded circular cross-sections, while 3D structures are then obtained by stacking the cross-sections with or without a twist between different scaffold layers. The effective mechanical properties of different scaffold configurations are presented and compared using an energy-based efficient numerical method, pointing out the versatility of the design procedure to separately govern longitudinal and transverse anisotropic scaffold properties. Among these configurations, a helical structure exhibiting couplings between transverse and longitudinal properties is proposed and permits to extend the adaptability of the proposed framework. In order to investigate the capacity of common additive manufacturing techniques to fabricate the proposed structures, a subset of these configurations is elaborated using a standard SLA setup, and subjected to experimental mechanical testing. Despite observed geometric differences between the initial design and the actual obtained structures, the effective properties are satisfyingly predicted by the proposed computational method. Promising perspectives are offered concerning the design of self-fitting scaffolds with on-demand properties depending on the clinical application.

Electrochemical characterization of plutonium in n-tributyl phosphate.

This work investigates the electrochemical behavior of Pu(iv) and Pu(vi) complexes in n-tributylphosphate (TBP) as an entry to the electrochemical characterization of these complexes in organic extractants related to nuclear fuel reprocessing. Glassy carbon electrodes were used to show that Pu(iv) and Pu(vi) complexes display a reversible electrochemical reduction wave in TBP previously equilibrated with aqueous nitric acid solution. We investigated the reduction of Pu(iv) and Pu(vi) nitrato complexes extracted into TBP, with the aim to get thermodynamic (formal potential) and kinetic (diffusion coefficient) information about Pu(iv)/Pu(iii) and Pu(vi)/Pu(v) redox couples in the TBP medium. The formal potentials of the two redox couples were respectively 0.510 ± 0.005 and 0.478 ± 0.005 V per SCE in TBP equilibrated with 3 mol L-1 nitric acid at room temperature. The diffusion coefficient values of Pu(iv) and Pu(vi) species were estimated to be 0.72 × 10-6 and 0.77 × 10-6 cm2 s-1 respectively. Also, the Pu(iv) reduction showed a Nernstian dependence on the logarithm of nitric acid concentration in the organic phase, featuring the exchange of nitrates upon reduction of Pu(iv).

[Job insecurity, unemployment and health: results from the health examination centers of the French General Health Insurance]. / Santé et instabilité professionnelle : résultats issus des centres d'examens de santé de l'assurance-maladie.

BACKGROUND: Job insecurity has increased over the last 30 years. Socioeconomic changes have led to various insecure employment categories, including fixed term employment, part time employment and government sponsored jobs. This study was aimed at investigating relationships between employment status and health. METHODS: The study population was composed of 767,184 people, aged 26 to 59 years, examined between 2003 and 2005 in the Health Examination Centers of the French General Health Insurance. Employment status was defined using insecure employment (combining permanent/fixed-term contracts and part-time/full time), government sponsored jobs and duration of unemployment (from <6 months to > or =3 years). Health indicators were poor perceived health, smoking, lack of gynecological follow-up, obesity, untreated caries and high blood pressure. Data were analysed by logistic regression (odds ratios [OR]) adjusted on age, occupational social class and education level, the reference category being permanent full time contracts (OR=1). RESULTS: Significant level-dependent relations with health were observed between non permanent versus permanent employments, part time versus full time. Most OR of unemployed people were higher than those of having employment and increased with duration of unemployment. For example, for poor perceived health in men, OR ranged between 1.00 and 1.68 (95%CI 1.57-1.78) according to job insecurity categories, and between 1.75 (95%CI 1.67-1.83) and 2.80 (95%CI 2.72-2.89) according to duration of unemployment. For obesity in women, OR increased from 1.00 to 1.48 (95%CI 1.37-1.60) in active women and from 1.35 (95%CI 1.27-1.44) to 1.77 (95%CI 1.70-1.84) in unemployed. CONCLUSIONS: This study showed quantitative relationships between job insecurity, unemployment and health. In particular, workers having government-sponsored jobs and long-time unemployed people were at high risk of health problems.

[Posterior IVS: feasibility and preliminary results in a continuous series of 108 cases]. / Colpopexie infracoccygéale translévatorienne postérieure (IVS): faisabilité et premiers résultats d'une série continue de 108 cas.

OBJECTIVE: We present a continuous series of 108 patients operated for genital prolapse by vaginal route using the Posterior Intravaginal Slingplasty (PIVS) technique (IVS 02 Tyco Healthcare, polypropylene multifilament band), associated to prosthetic repair of cystocele and/or rectocele if present by interposition of a mesh (Surgipro Mesh Tyco Healthcare). PATIENTS AND METHODS: Inclusion criteria were C and/or D point superior to -1 cm. The main criterion is the assessment of feasibility, morbidity and anatomical results obtained for the treatment of level 1 genital prolapse with an average follow-up of 19 months. The secondary criterion is to assess the same elements for the treatment of associated cystocele and rectocele. RESULTS: Seventy-three patients presented with a cystocele (Ba>-1 cm) and eighty-seven with a rectocele (Bp>-1 cm). Nineteen patients had a hysterectomy, twenty had amputation of the cervix and forty-nine were treated for stress urinary incontinence by anterior IVS. Perioperative complications consisted of seven bladder injuries, one injury to the lower rectum during dissection. Postoperative complications were: a loss more than 2 g haemoglobin for seven patients, two haematomas in the cave of Retzius, one haematoma of the pararectal fossa with secondary superinfection requiring mesh removal. Three erosions occurred: two in front of the vesicovaginal prosthesis and one in front of the recto-vaginal prosthesis. The latter became secondarily super infected and had to be removed. With regard to the anatomical result, one failure was noted for the Posterior IVS excluding the two patients in whom the prosthetic material had to be removed. For the anterior compartment, eight failures occurred. From a functional perspective, we noted one case of dyspareunia due to fibrous retraction and seven patients complained of de novo stress urinary incontinence and eight of moderate voiding obstruction. DISCUSSION AND CONCLUSIONS: The technical feasibility is excellent. Feasibility of level 2 repair, anterior or posterior, but results on cystocele are insufficient in case of lateral defect.

[Comparison of the individual deprivation index of the French Health Examination Centres and the administrative definition of deprivation]. / Comparaison du score individuel de précarité des centres d'examens de santé, EPICES, à la définition socio- administrative de la précarité.

In French Health Examination Centres, populations in deprived situation were usually defined by administrative criteria The aim of the study was to investigate whether EPICES, a new individual index of deprivation, was more strongly related to health status than an administrative classification. The EPICES score was calculated on the basis of 11 weighted questions related to material and social deprivation. Participants were 197, 389 men and women, aged over 18, encountered in 2002 in French Health Examination Centres. Relationships between health status, health-related behaviours, access to health care, EPICES and the administrative classification of deprivation were analyzed by logistic regression. The associations between EPICES and the study variables were stronger than those observed for the administrative definition. The comparison also showed socially disadvantaged people with poor health identified by the EPICES score who were not by the administrative classification. These results showed that the EPICES score can be a useful tool to improve the identification of deprived people having health problems associated to deprivation.

[The triple perineal operation with prosthesis. First 100 cases results]. / La triple operation périnéale avec prothèses: technique opératoire et premiers résultats à propos de 100 cas.

The authors describe the technique of Triple Operation for Prolapses with Prostheses for the surgical cure of genital prolapse using a recto-vaginal interposition prosthesis for cystocele, rectocele and suspension of the vaginal dome by a posterior retro- and trans-levator muscle strip. The preliminary results over a continuous series of 100 patients operated on between June 2001 and June 2003 showed perioperative complications (7 bladder injuries) and postoperative complications (4 vaginal erosions related to the prosthesis including one that was secondarily infected, and a hematoma with secondary abscess of the pararectal fossa which required the ablation of the material). As far as anatomy was concerned, the results were excellent for the correction of hysterocele, apical prolapse and rectocele. On the functional level, dyspareunia was noted. Six of the ten preoperative mechanical dyschesias were considerably improved.

[Three-way prosthetic repair of the pelvic floor]. / La triple opération périnéale avec prothèses.

We describe the triple operation for prolapse with prosthesis in patients with pelvic organ prolapse using a vesicovaginal mesh for the cystocele, a rectovaginal mesh for the rectocele and a posterior retro-and trans levatory vault suspension sling. Preliminary results in a consecutive series of 92 patients who underwent surgery between June 2001 and December 2002 showed three cases of vaginal erosion in contact with the prosthetic material, and one hematoma of the pararectal fossa with secondary abscess formation requiring ablation of the implant. There was one immediate anatomic failure. Function was good with no reports of dyspareunia or dyschesia.

Infección por virus de inmunodeficiencia humana en la embarazada. Importancia del conocimiento de la infección en el embarazo y factores de riesgo en la transmisión perinatal / Human immunodeficiency virus infection in pregnant women. The importance of recognizing the infection during pregnancy and risk factors for perinatal transmission

BACKGROUND: Using adequate infection control measures, the rate of vertical transmission of human immunodeficiency virus (HIV) during pregnancy, has been reduced to 3 per cent in Chile. AIM: To determine vertical transmission rate and risk factors associated to perinatal infection in pregnant women with known (KI) and unknown HIV infection (UI). PATIENTS AND METHODS: HIV infected pregnant women whose deliveries were attended at the San Borja Arriaran Hospital were included. Antiretroviral therapy (ART) has been used since 1995 (Zidovudine 13 patients, biOtherapy 4 and triple therapy 14 patients). Newborns have received ART since 1995. Premature labor without evident cause, premature rupture of membranes, and rupture of membranes over 4 h before delivery were evaluated. Delivery was by elective cesarean section since 1993. Breast feeding was avoided. Pregnant women with UI (suspected disease after delivery due to child or mother pathology) did not received ART. Delivery and breast feeding were managed with common obstetrical-neonatal criteria. RESULTS: Fifty three HIV infected pregnant women were studied (43 with KI and 10 with UI). Four children (36.4 per cent) from the KI group and seven (63.6 per cent from the UI group became infected. The global rate of vertical transmission among KI group was significantly lower than UI group: 9.5 per cent (4/42) vs 70.0 per cent(7/10) p < 0.001. Using ART, this rate was further reduced to 6.5 per cent (2/31) and with bitherapy or triple therapy to 0 per cent (0/18). Breast feeding, vaginal delivery, premature delivery with no clinical cause, premature rupture of membranes, rupture of membranes longer than 4 h and lack of ART, were significantly more common in the UI group, compared with KI group. CONCLUSIONS: Vertical transmission in pregnant women with KI is significantly lower compared with UI. Risk factors increasing HIV perinatal infection are: breast feeding, lack of ART, vaginal delivery, premature rupture of membranes, rupture of membranes > 4 h and premature labor without a clinical cause.

Nurses' attitudes and practices in sickle cell pain management.

Professional objectivity should be the primary focus of patient care. Health care professionals are at times reluctant to give opioids out of fear that patients may become addicted, which would result in the undertreatment of pain. The influence of nurses' attitudes on the management of sickle cell pain was studied. The variables of age, education, area of practice, and years of active experience were considered. Of the respondents, 63% believed addiction was prevalent, and 30% were hesitant to administer high-dose opioids. Study findings suggest that nurses would benefit from additional education on sickle cell disease, pain assessment and management, and addiction. Educational recommendations are discussed.

The transcriptional role of Smads and FAST (FoxH1) in TGFbeta and activin signalling.

The Smad family of proteins are critical components of the TGFbeta superfamily signalling pathway. Ligand addition induces phosphorylation of specific receptor-regulated Smads, which then form heteromeric complexes with the common mediator Smad, Smad4. This complex then translocates from the cytoplasm into the nucleus. Once there, the R-Smad/Smad4 complex interacts with a variety of DNA binding proteins and is thereby targetted to a diverse array of gene promoters. The Smad-containing DNA binding complex can then positively or negatively regulate gene expression through the recruitment of co-activators and co-repressors. Xenopus FAST (now known as FoxH1) was the first Smad DNA binding partner identified and the FoxH1 family now includes related proteins from mouse, human and Zebrafish. In all organisms examined, FoxH1 is expressed primarily during the earliest stages of development and thus FoxH1 is thought to play a critical role in mediating TGFbeta superfamily signals during these early developmental stages. Other Smad partners range from those that are ubiquitously expressed to others that are present only in specific cell types or developmental stages. Thus, it is the interaction of Smads with a wide range of specific transcriptional partners that is important for the generation of diverse biological responses to TGFbeta superfamily members.

FoxH1 (Fast) functions to specify the anterior primitive streak in the mouse.

The node and the anterior visceral endoderm (AVE) are important organizing centers that pattern the mouse embryo by establishing the anterior-posterior (A-P), dorsal-ventral (D-V), and left-right (L-R) axes. Activin/nodal signaling through the Smad2 pathway has been implicated in AVE formation and in morphogenesis of the primitive streak, the anterior end of which gives rise to the node. The forkhead DNA-binding protein, FoxH1 (or Fast), functions as a Smad DNA-binding partner to regulate transcription in response to activin signaling. Here, we show that deletion of FoxH1 in mice results in failure to pattern the anterior primitive streak (APS) and form node, prechordal mesoderm, notochord, and definitive endoderm. In contrast, formation of the AVE can occur in the absence of FoxH1. The FoxH1 mutant phenotype is remarkably similar to that of mice deficient in the forkhead protein Foxa2 (HNF3beta), and we show that Foxa2 expression is dependent on FoxH1 function. These results show that FoxH1 functions in an activin/nodal-Smad signaling pathway that acts upstream of Foxa2 and is required specifically for patterning the APS and node in the mouse.

Transcriptional regulation by Smads: crosstalk between the TGF-beta and Wnt pathways.

BACKGROUND: Several studies have shown that cooperation between transforming growth factor beta (TGF-beta) and Wnt/wingless signaling pathways plays a role in controlling certain developmental events. These factors elicit their biological effects through distinct pathways in which TGF-beta and Wnt signaling induce activation of the transcriptional regulators Smads and lymphoid enhancer binding factor/T-cell-specific factor (LEF/TCF), respectively. To understand the mechanism for cooperativity between these pathways, we have investigated the molecular mechanism for this synergistic effect. METHODS: Transcriptional assays were conducted by transient transfection of HepG2 cells with use of luciferase reporter constructs. Protein/protein interaction studies were conducted in vitro with the use of glutathione-S-transferase pull-down assays and in intact cells by immunoprecipitation and immunoblotting. RESULTS: We show that Smads physically interact with LEF1/TCF transcription factors and that specific DNA binding sites in the Xenopus twin promoter are required for synergistic activation by TGF-beta and Wnt pathways. In addition, we demonstrate that TGF-beta-dependent activation of LEF1/TCF target genes can occur independently of beta-catenin, an essential component of the Wnt signaling pathway. CONCLUSIONS: TGF-beta and Wnt signaling pathways can independently or cooperatively regulate LEF1/TCF target genes. This suggests that the cooperation between these pathways may be important for the specification of cell fates during development.

Association of Smads with lymphoid enhancer binding factor 1/T cell-specific factor mediates cooperative signaling by the transforming growth factor-beta and wnt pathways.

The transforming growth factor-beta (TGFbeta) and Wnt/wingless pathways play pivotal roles in tissue specification during development. Activation of Smads, the effectors of TGFbeta superfamily signals, results in Smad translocation from the cytoplasm into the nucleus where they act as transcriptional comodulators to regulate target gene expression. Wnt/wingless signals are mediated by the DNA-binding HMG box transcription factors lymphoid enhancer binding factor 1/T cell-specific factor (LEF1/TCF) and their coactivator beta-catenin. Herein, we show that Smad3 physically interacts with the HMG box domain of LEF1 and that TGFbeta and Wnt pathways synergize to activate transcription of the Xenopus homeobox gene twin (Xtwn). Disruption of specific Smad and LEF1/TCF DNA-binding sites in the promoter abrogates synergistic activation of the promoter. Consistent with this observation, introduction of Smad sites into a TGFbeta-insensitive LEF1/TCF target gene confers cooperative TGFbeta and Wnt responsiveness to the promoter. Furthermore, we demonstrate that TGFbeta-dependent activation of LEF1/TCF target genes can occur in the absence of beta-catenin binding to LEF1/TCF and requires both Smad and LEF1/TCF DNA-binding sites in the Xtwn promoter. Thus, our results show that TGFbeta and Wnt signaling pathways can independently or cooperatively regulate LEF1/TCF target genes and suggest a model for how these pathways can synergistically activate target genes.

Hemispheric differences in variability of fissural patterns in parasylvian and cingulate regions of human brains.

We have determined different patterns of fissurization in Broca's area, the gyrus of Heschl, the planum temporale, the inferior parietal lobe, and the cingulate sulcus. Such patterns were asymmetrically distributed, indicating increased folding on the left side in most cases. More folding can sometimes be related to a larger cortical area, resulting in increased processing capacities in the respective brain region. Furthermore, the brain regions associated with the asymmetrical sulci are involved in lateralized functions. Of special interest are the asymmetries observed in regions corresponding to the inferior parietal lobe (the accessory postcentral sulcus and the intraparietal sulcus), which, according to recent studies, is involved in linguistic working memory. We did not detect a tendency of distinct fissurization patterns in a given brain region to be associated with specific patterns in other fissures, indicating that the different fissure types develop independently in each brain region and can therefore be determined by local processes. These descriptions are of relevance to imaging studies that intend to establish correspondences between gross morphology and functional parameters such as behavior and brain activation.

Perceived and physiological indicators of relaxation: as different as Mozart and Alice in chains.

The effects of listening to different types of music on perceived and physiological indicators of relaxation were evaluated. Fifty-six undergraduate students, 24 males and 32 females, mean age of 21, were randomly assigned to listen to classical, hard rock, self-selected relaxing music, or no music. Participants' relaxation level, skin temperature, muscle tension and heart rate were evaluated before and after exposure to a music condition. Analyses of variance using baseline measures as covariates indicated that skin temperature decreased for all conditions (p = 0.001) and the classical, self-selected relaxing music and no music groups reported significant increases in feelings of relaxation (p = 0.004). These results partially support the hypothesis that classical and self-selected relaxing music can increase perceptions of relaxation to a greater degree than listening to hard rock music. However, no differences were found between different types of music on physiological indicators of arousal. Implications for using music to reduce stress were discussed.

Smad2 and Smad3 positively and negatively regulate TGF beta-dependent transcription through the forkhead DNA-binding protein FAST2.

We identify a mammalian forkhead domain protein, FAST2, that is required for induction of the goosecoid (gsc) promoter by TGF beta or activin signaling. FAST2 binds to a sequence in the gsc promoter, but efficient transcriptional activation and assembly of a DNA-binding complex of FAST2, Smad2, and Smad4 requires an adjacent Smad4 site. Smad3 is closely related to Smad2 but suppresses activation of the gsc promoter. Inhibitory activity is conferred by the MH1 domain, which unlike that of Smad2, binds to the Smad4 site. Through competition for this shared site, Smad3 may prevent transcription by altering the conformation of the DNA-binding complex. Thus, we describe a mechanism whereby Smad2 and Smad3 positively and negatively regulate a TGF beta/activin target gene.

Use of the Modified Mini-Mental State Examination with children.

The validity and reliability of the modified version of the Mini-Mental State Examination with children was examined. The Modified Mini-Mental State Examination was administered to 99 children between 4 and 12 years of age (45 males and 54 females) to assess expected scores for nonclinical children and with a clinical sample. Concurrent validity was assessed through correlations of Modified Mini-Mental State Examination scores with Wechsler Intelligence scores and Child Behavior Checklist scores. The Modified Mini-Mental State Examination was administered to 26 children on two occasions to determine test-retest reliability. Means and standard deviations of scores are reported by age and grade level. Test-retest reliability coefficients were positively significant. For the nonclinical sample, Modified Mini-Mental State Examination scores were significantly and positively correlated with Verbal IQ and Child Behavior Checklist scores. Modified Mini-Mental State Examination scores were significantly correlated with Verbal IQ scores in the total and clinical samples.

Low temperature perception in plants: effects of cold on protein phosphorylation in cell-free extracts.

Activities of prevalent protein phosphatases decreased by nearly 95% and those of individual protein kinases were differentially reduced at low temperature. Inhibition of phosphatase activity at temperatures below 12 degrees C resulted in marked hyperphosphorylation of a 58-kDa protein (PP58). The temperature threshold for hyperphosphorylation of PP58 coincided with the known threshold for cold-induced calcium influx. Since calcium influx is triggered by several environmental stresses, we propose that the observed direct effects of cold on the phosphorylation of specific proteins enable cells to couple a shared calcium signal to a cold-specific transduction pathway.

Narcissism and causal attribution.

This study examined the relationship between scores on narcissistic personality traits and causal attributions to positive and negative events. 119 undergraduate students in psychology as participants completed the Narcissistic Personality Inventory-40, the Attributional Style Questionnaire, and several Self-referencing Closed-ended Vignettes. Analyses indicated that men who scored higher on the Narcissistic Personality Inventory-40 made more internal and stable attributions to positive events and more external and unstable attributions to negative events than did men who scored lower on the Narcissistic Personality Inventory-40. Also scores on the Self-referencing Closed-ended Vignettes correlated significantly and positively with the Attributional Style Questionnaire, providing evidence for the validity of the vignettes.