Single GaAs nanowire based photodetector fabricated by dielectrophoresis.

Mechanical manipulation of nanowires (NWs) for their integration in electronics is still problematic because of their reduced dimensions, risking to produce mechanical damage to the NW structure and electronic properties during the assembly process. In this regard, contactless NW manipulation based methods using non-uniform electric fields, like dielectrophoresis (DEP) are usually much softer than mechanical methods, offering a less destructive alternative for integrating nanostructures in electronic devices. Here, we report a feasible and reproducible dielectrophoretic method to assemble single GaAs NWs (with radius 35-50 nm, and lengths 3-5 µm) on conductive electrodes layout with assembly yields above 90% per site, and alignment yields of 95%. The electrical characteristics of the dielectrophoretic contact formed between a GaAs NW and conductive electrodes have been measured, observing Schottky barrier like contacts. Our results also show the fast fabrication of diodes with rectifying characteristics due to the formation of a low-resistance contact between the Ga catalytic droplet at the tip of the NW when using Al doped ZnO as electrode. The current-voltage characteristics of a single Ga-terminated GaAs NW measured in dark and under illumination exhibit a strong sensitivity to visible light under forward bias conditions (around two orders of magnitude), mainly produced by a change on the series resistance of the device.

A Novel Growth Method To Improve the Quality of GaAs Nanowires Grown by Ga-Assisted Chemical Beam Epitaxy.

The successful synthesis of high crystalline quality and high aspect ratio GaAs nanowires (NWs) with a uniform diameter is needed to develop advanced applications beyond the limits established by thin film and bulk material properties. Vertically aligned GaAs NWs have been extensively grown by Ga-assisted vapor-liquid-solid (VLS) mechanism on Si(111) substrates, and they have been used as building blocks in photovoltaics, optoelectronics, electronics, and so forth. However, the nucleation of parasitic species such as traces and nanocrystals on the Si substrate surface during the NW growth could affect significantly the controlled nucleation of those NWs, and therefore the resulting performance of NW-based devices. Preventing the nucleation of parasitic species on the Si substrate is a matter of interest, because they could act as traps for gaseous precursors and/or chemical elements during VLS growth, drastically reducing the maximum length of grown NWs, affecting their morphology and structure, and reducing the NW density along the Si substrate surface. This work presents a novel and easy to develop growth method (i.e., without using advanced nanolithography techniques) to prevent the nucleation of parasitic species, while preserving the quality of GaAs NWs even for long duration growths. GaAs NWs are grown by Ga-assisted chemical beam epitaxy on oxidized Si(111) substrates using triethylgallium and tertiarybutylarsine precursors by a two-step-based growth method presented here; this method includes a growth interruption for an oxidation on air between both steps of growth, reducing the nucleation of parasitic crystals on the thicker SiO x capping layer during the second and longer growth step. VLS conditions are preserved overtime, resulting in a stable NW growth rate of around 6 µm/h for growth times up to 1 h. Resulting GaAs NWs have a high aspect ratio of 85 and average radius of 35 nm. We also report on the existence of characteristic reflection high-energy electron diffraction patterns associated with the epitaxial growth of GaAs NWs on Si(111) substrates, which have been analyzed and compared to the morphological characterization of GaAs NWs grown for different times under different conditions.

CD40L and TNF both activate the classical NF-κB pathway, which is not required for the CD40L induced alternative pathway in endothelial cells.

CD40L and TNF signal through engagement of their respective receptors, which are both members of the TNF receptor family. They use partially common signaling molecules leading, among others, to activation of the NF-κB pathway. However, whereas TNF activates the classical, CD40L has been reported to activate the alternative NF-κB pathway, leading to the anticipation that differences in the pattern of inflammatory gene expression would occur. Here, we have compared the gene expression repertoire of CD40L (CD154) and TNF stimulated HUVEC and report that unexpectedly, apart from a stronger response to TNF, no major qualitative differences could be observed. This applies for the period of up to 6 h, a time where the alternative pathway has already been activated. Analysis of the early events after receptor engagement revealed that both TNF and CD40L activate the classical NF-κB pathway, and confirm activation of the alternative by the latter. Furthermore, using genetic and pharmacological inhibition of the classical pathway we show that activation of the alternative occurs independently of the former. This reveals novel insights into NF-κB signaling by CD40L and TNF in endothelial cells.

Does preoperative psychologic distress influence pain, function, and quality of life after TKA?

BACKGROUND: Preoperative psychologic distress is considered to be a risk factor for clinical dissatisfaction stemming from persistent pain and physical limitations after elective orthopaedic procedures such as lower-extremity arthroplasty. However, the degree to which psychologic distress, specifically in the form of anxiety and depression, influences surgical results has been poorly characterized. QUESTIONS/PURPOSES: We analyzed the effect of preoperative psychologic distress on changes in pain, function, and quality of life 1 year after elective TKA. METHODS: In this prospective cohort study, we assessed patients who underwent TKAs in 2009 and 2010. Before surgery, patients completed the Folstein Mini Mental Test, the Hospital Anxiety and Depression Scale (HAD), The Knee Society Score(©), the WOMAC quality-of-life questionnaire, and the VAS for pain. The patients were divided into two groups based on the degree of psychologic distress on the HAD Scale, and the groups were compared in terms of the above-listed clinical outcomes tools 1 year after surgery using multivariate linear models. Two hundred sixty-three patients met the inclusion criteria, and 202 (77%) completed the study protocol. RESULTS: The presence of preoperative psychologic distress did not influence 1-year postoperative pain assessment (average reduction in pain, 40.33; 95% CI, 36.9-43.8; p = 0.18). The only factor influencing change in pain experienced by patients was the preoperative pain recorded (R(2) = 0.31; ß = -0.82; p < 0.001). The patients experiencing preoperative psychologic distress obtained poorer outcomes in function (R(2) = 0.16; ß = -5.62; p = 0.001) and quality of life (R(2) = 0.09; ß = -0.46; p < 0.001) 1 year after receiving TKA. CONCLUSIONS: The presence of preoperative psychologic distress is associated with worse 1-year outcomes for function and quality of life in patients undergoing TKA. Interventions designed to reduce psychologic distress may be indicated for patients to undergo this type of surgery, and incorporation of these data into discussions with patients may facilitate informed and shared decision making regarding the surgical treatment of knee osteoarthritis. LEVEL OF EVIDENCE: Level II, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Evaluation of Dentaport ZX and Raypex 6 electronic apex locators: an in vivo study.

INTRODUCTION: Raypex 6 is an electronic apex locator (EAL) that has not yet been tested in vivo. The purpose of this in vivo study was to compare the accuracy of two EALs: the Dentaport ZX and the Raypex 6. METHODS: The study involved 36 straight single-rooted teeth. A 10-K file was advanced until the EAL detected the major foramen. The file was fixed in a replaceable pattern of light-cured composite. The apical part of each canal was trimmed to expose the file tip. The distances from the file tips to the major foramen were measured. RESULTS: Wilcoxon's signed Rank test found no significant differences between the Dentaport ZX and Raypex 6 in terms of their abilities to detect the major foramen (P = .52) The Dentaport ZX was accurate 82.35% of the time to ± 0.5 mm and 97.05% of the time to ± 1 mm, whereas the Raypex 6 was accurate 88.22% of the time to ± 0.5 mm and 100% of the time to ± 1 mm. CONCLUSIONS: No statistically significant differences were observed between the performance of the Dentaport ZX and Raypex 6 EALs under the in vivo clinical conditions used in this study.

Partial Two-Stage Exchange for Infected Total Hip Arthroplasty: A Treatment to Take into Account.

INTRODUCTION: Two-stage revision is the gold standard for chronic periprosthetic joint infection (PJI). The removal of well-fixed implants, especially the femoral component, can be extremely difficult and additional osteotomies may be needed, which is time-consuming and results in bone stock loss. When the femoral stem is osseointegrated, there is no clear indication for the use of partial two-stage revision. The primary objective was to assess infection eradication after surgery. METHODS: Retrospective study of specific case series. A total of eight patients with a chronic uncemented PJI, in the setting of complex revision surgeries, were treated with partial two-stage revision, which included selective retention of the well-fixed femoral component and complete acetabular removal. Stem retention was carried out regardless of the bacteria or associated comorbidities. RESULTS: All patients were re-revision cases with at least two previous surgeries (range, 2-4). Complex revisions were performed in five cases (non-articulated spacer) and simple revisions in three cases (articulated spacer). The minimum follow-up time was 24 months (range, 24-132 months). The infection eradication rate at final follow-up was 100%. CONCLUSION: Partial two-stage reconstruction is a promising technique for the treatment of chronic PJI in patients with a well-fixed stem and complex re-revision acetabular procedures. Further prospective studies and prolonged follow-ups are required to confirm our results.

Prevention of Periprosthetic Joint Infection in Total Hip and Knee Replacement: One European Consensus.

Periprosthetic joint infection (PJI) is a devastating complication in total hip and knee replacement. Its prevention is key to decrease the incidence and avoid some consequences that seriously impact patients and health systems. In view of the variety of recommendations and guidelines, we decided to conduct an expert, peer-reviewed European consensus analysis about the pre-, intra-, and postoperative prevention of PJI. A multinational group of practicing orthopedic experts developed a series of 47 consensus statements in 6 main groups of intervention, and a 2-stage Delphi approach was launched with a threshold for agreement at 75% and for very high agreement at more than 90%. A total of 306 orthopedic surgeon responses were gathered from 9 countries. Consensus was reached for 42/47 statements, 31/47 of which achieved a very high consensus. Many preoperative actions gathered strong consensus, although areas like the use of alcoholic chlorhexidine or the timing of hair removal did not attain strong consensus, despite available evidence. Intra- and postoperative actions showed more variability regarding incise drapes, skin suturing techniques, and wound follow-up. This study confirms an important consensus among orthopedic surgeons across Europe in many areas well known to contribute to the prevention of PJI; however, there are still grounds for improvement.

Comparative proteomics reveals unexpected quantitative phosphorylation differences linked to platelet activation state.

There is a need to assess platelet activation in patients with thrombotic disorders. P-selectin and activated integrin αIIbß3 are usually quantified by flow cytometry to measure platelet activation. Monitoring changes in vasodilator-stimulated phosphoprotein (VASP) phosphorylation is an established method to determine the platelet-reactivity status. To study disruptions of platelet reactivity more comprehensively, we compared the human non-secretory platelet proteome after in-vitro -activation and -inhibition with their respective untreated controls using unbiased fluorescence two-dimensional differential in-gel electrophoresis. The non-secretory platelet proteome was more severely affected during inhibition than during activation. Strikingly, while VASP reached a 1.3-fold increase in phosphorylation levels in inhibited platelets, other protein kinase A targets showed several-fold stronger inhibition-induced phosphorylation levels, including LIM and SH3 domain protein 1 (6.7-fold), Src kinase-associated phosphoprotein 2 (4.6-fold), and Ras-related protein Rap1b (4.1-fold). Moreover, phosphorylation of integrin-linked protein kinase (ILK) and pleckstrin (PLEK) species was associated with P-selectin surface expression. The discrimination power between activation and inhibition was more pronounced for dephosphorylated ILK (3.79 Cohen's d effect size) and phosphorylated PLEK (3.77) species than for P-selectin (2.35). These data reveal new insights into the quantitative changes of the platelet reactivity proteome and suggest powerful alternatives to characterise their activation and inactivation potential.

Androgen receptor dampens tissue factor expression via nuclear factor-κB and early growth response protein 1.

Essentials Androgen deprivation increases the rate of venous thromboembolism in prostate cancer patients. We characterized androgen receptor-mediated tissue factor regulation in prostate epithelial cells. Androgen receptor is dampening tissue factor expression in prostate epithelial cells. Androgen deprivation could enhance tissue factor expression and raise venous thromboembolism rates. SUMMARY: Background Prostate cancer is one of the leading causes of cancer death in men. Advanced prostate cancer is usually treated by androgen deprivation therapy (ADT), which is aimed at reducing circulating testosterone levels to reduce cancer growth. There is growing evidence that ADT can increase the rate of venous thromboembolism (VTE) in prostate cancer patients. The tissue factor (TF) gene is one of the most important mediators of coagulation and VTE, but, so far, there are limited data on androgen receptor (AR)-mediated TF gene expression. Objectives To characterize AR-mediated TF regulation in vitro and in vivo. Methods We used the androgen-dependent prostate cancer cell lines LNCaP and MyC-CaP to test whether TF expression is regulated by AR. Furthermore, we cloned the TF gene promoter into a luciferase reporter vector to identify the transcription factor-binding sites that mediate TF regulation downstream of AR. Finally, we used castration experiments in mice to characterize AR-mediated TF regulation in vivo. Results TF is directly regulated by AR. In LNCaP cells, nuclear factor-κB signaling and EGR1 mediate TF expression. By using castration experiments in mice, we could detect upregulation of TF and early growth response protein 1 mRNA and protein expression in prostate epithelial cells. Conclusion AR is crucial for dampening TF expression, which could be important for increased TF expression and TF-positive microvesicle release in androgen-deprived prostate cancer patients.

Myeloid PTEN deficiency impairs tumor-immune surveillance via immune-checkpoint inhibition.

Tumor-host interaction is determined by constant immune surveillance, characterized by tumor infiltration of myeloid and lymphoid cells. A malfunctioning or diverted immune response promotes tumor growth and metastasis. Recent advances had been made, by treating of certain tumor types, such as melanoma, with T-cell checkpoint inhibitors. This highlights the importance of understanding the molecular mechanisms underlying the crosstalk between tumors and their environment, in particular myeloid and lymphoid cells. Our aim was to study the contribution of the myeloid PI3K/PTEN-signaling pathway in the regulation of tumor-immune surveillance in murine models of cancer. We made use of conditional PTEN-deficient mice, which exhibit sustained activation of the PI3K-signaling axis in a variety of myeloid cell subsets such as macrophages and dendritic cells (DCs). In colitis-associated colon cancer (CAC), mice deficient in myeloid PTEN showed a markedly higher tumor burden and decreased survival. We attributed this observation to the increased presence of immune-modulatory conventional CD8α(+) DCs in the spleen, whereas other relevant myeloid cell subsets were largely unaffected. Notably, we detected enhanced surface expression of PD-L1 and PD-L2 on these DCs. As a consequence, tumoricidal T-cell responses were hampered or redirected. Taken together, our findings indicated an unanticipated role for the PI3K/PTEN-signaling axis in the functional regulation of splenic antigen-presenting cells (APCs). Our data pointed at potential, indirect, tumoricidal effects of subclass-specific PI3K inhibitors, which are currently under clinical investigation for treatment of tumors, via myeloid cell activation.

[Prevalence of depressive symptoms in hospitalized elderly medical patients]. / Implicaciones de los síntomas depresivos en los ancianos hospitalizados por afección médica.

INTRODUCTION: Depressive symptoms in hospitalized patients are very common, and they have been related to higher mortality. The aim of the study was to estimate the prevalence of depressive symptoms in hospitalized elderly patients and its relationship to various diseases, as well as their functional and mental status and mortality. MATERIAL AND METHODS: A total of 115 patients over 64 years of age were prospectively studied. The validated Spanish version of the Geriatric Depression Scale of Yesavage (15-item version) was used. Patients were considered to have depressive symptoms if ≥6 points were obtained. The demographic characteristics, the Charlson comorbidity index, the diagnosis at admission, the functional status assessed by the Barthel and Lawton-Brodie index, the mental capacity assessed by the Pfeiffer questionnaire, the length of the hospital stay, and hospital mortality were recorded. RESULTS: Out of the 115 patients studied, with a mean age of 70.5 years, 71 (61.7%) were female. Depressive symptoms were observed in 46 patients (40%, 95% CI:34.8-43.9). Patients who died showed a significantly higher score on the Yesavage scale (P=.04). The multivariate analysis showed a significantly independent association between depressive symptoms and functional capacity (P=.026), mental status (P=.021), renal failure (P=.001), liver disease (P=.018), and osteoarthritis (P=.017), but losing the previously seen significant association with diabetes (P=.43). CONCLUSIONS: The prevalence of depressive symptoms in hospitalized elderly patients is high, and is associated with the diagnoses of renal failure, liver disease and osteoarthritis, with a higher comorbidity and especially with a poorer functional capacity.

10 years results of an uncemented metaphyseal fit modular stem in elderly patients.

BACKGROUND: There are concerns with regard to the femoral fixation in cementless total hip arthroplasty in elderly patients. We report a retrospective analysis of clinical and radiological results of uncemented metaphyseal fit modular stem in elderly patients irrespective of anatomic characterstics of proximal femur. MATERIALS AND METHODS: This study reviews the outcomes of 60 primary hip replacements using a metaphyseal fit modular stem (third-generation Omniflex stem) conducted in 54 patients, of age 75 years or older. After a mean follow-up of 10,4 years, complete clinical and radiographic records were available for 52 hips of 48 patients. The patients were evaluated by Harris Hip Score (HHS). RESULTS: There was a significantly improved pain score and Harris Hip Score (41,6 to 83,2). Six stems (11.53%) were revised: four because of periprosthetic fracture; one stem was well fixed, but presented a large osteolytic lesion in the metaphyseal area and the last stem was revised because of aseptic loosening. Stem survival taking aseptic loosening as the end-point was 98%. Bone atrophy in the proximal femur caused by stress shielding was observed in 39 stems (75%), but there was no case of subtrochanteric stress shielding. Moreover, atrophy appeared within two years postoperatively, with no extension thereafter. CONCLUSIONS: We achieved good clinical and radiographic results by uncemented metaphyseal fit femoral stem regardless of patient's age and femoral canal type.

Long-term exercise training in overweight adolescents improves plasma peptide YY and resistin.

The objective of this study was to investigate the effect of long-term exercise training on concentrations of five hormones related to appetite and insulin resistance in overweight adolescents. In addition, we were interested in the relationships of these hormones with each other and with anthropometric and/or cardiovascular disease marker changes. Participants were >or=the 85th percentile for BMI for age and sex and participated in an 8-month supervised aerobic training program. Anthropometrics, cardiovascular fitness assessment, and fasting blood samples were taken pre- and post-training. Glucose, insulin, total cholesterol (TC), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, leptin, active ghrelin, total peptide YY (PYY), adiponectin, and resistin concentrations were measured. The participants increased their time to exhaustion on an incremental treadmill test and decreased both percent body fat and blood triglyceride concentrations. Total PYY concentration increased and resistin concentration decreased after long-term exercise training, which are favorable outcomes. Leptin concentrations were related to weight, percent body fat, waist circumference, and triglyceride concentrations pre- and post-training. The changes in resistin concentrations were related to the changes in triglyceride concentrations. We conclude that long-term exercise training has beneficial effects for overweight adolescents with respect to PYY and resistin, hormones related to appetite and insulin sensitivity.

Implicaciones de los síntomas depresivos en los ancianos hospitalizados por afección médica / Prevalence of depressive symptoms in hospitalized elderly medical patients

Introducción. Los síntomas depresivos en los pacientes mayores hospitalizados son muy frecuentes, y se han asociado a una mayor mortalidad. Nos planteamos estimar la prevalencia de los síntomas depresivos en los ancianos hospitalizados y su relación con distintas afecciones, así como con su situación funcional, mental y mortalidad. Material y métodos. Se estudiaron prospectivamente 115 pacientes mayores de 64 años. Se utilizó la escala de depresión geriátrica de Yesavage en su versión de 15 ítems validada en español. Se consideró la presencia de los síntomas depresivos si se obtenían de 6 o más puntos. Se recogieron las características demográficas, el índice de comorbilidad de Charlson, los diagnósticos de ingreso, la situación funcional evaluada mediante el índice de Barthel y de Lawton-Brody, la capacidad mental evaluada mediante el cuestionario de Pfeiffer, la estancia y la mortalidad hospitalaria. Resultados. De los 115 pacientes estudiados con una edad media de 70,5 años, 71 (61,7%) eran mujeres. Se observaron síntomas depresivos en 46 pacientes (40%; IC 95%: 34,8-43,9). Los pacientes que fallecieron mostraron una puntuación significativamente superior en la prueba de Yesavage (p = 0,04). En el análisis multivariante se observó la asociación significativa independiente entre los síntomas depresivos y la capacidad funcional (p = 0,026), la capacidad mental (p = 0,021), la insuficiencia renal (p = 0,001), la hepatopatía (p = 0,018) y la artrosis (p = 0.017), perdiéndose la significación obtenida previamente para la diabetes (p = 0,43). Conclusiones. La prevalencia de síntomas depresivos en los ancianos hospitalizados es elevada, y se asocia con los diagnósticos de insuficiencia renal, hepatopatía y artrosis, con una mayor comorbilidad y especialmente con una peor capacidad funcional (AU)

Introduction: Depressive symptoms in hospitalized patients are very common, and they have been related to higher mortality. The aim of the study was to estimate the prevalence of depressive symptoms in hospitalized elderly patients and its relationship to various diseases, as well as their functional and mental status and mortality. Material and methods: A total of 115 patients over 64 years of age were prospectively studied. The validated Spanish version of the Geriatric Depression Scale of Yesavage (15-item version) was used. Patients were considered to have depressive symptoms if >=6 points were obtained. The demographic characteristics, the Charlson comorbidity index, the diagnosis at admission, the functional status assessed by the Barthel and Lawton-Brodie index, the mental capacity assessed by the Pfeiffer questionnaire, the length of the hospital stay, and hospital mortality were recorded. Results: Out of the 115 patients studied, with a mean age of 70.5 years, 71 (61.7%) were female. Depressive symptoms were observed in 46 patients (40%, 95% CI: 34.8-43.9). Patients who died showed a significantly higher score on the Yesavage scale (P=.04). The multivariate analysis showed a significantly independent association between depressive symptoms and functional capacity (P=.026), mental status (P=.021), renal failure (P=.001), liver disease (P=.018), and osteoarthritis (P=.017), but losing the previously seen significant association with diabetes (P=.43). Conclusions: The prevalence of depressive symptoms in hospitalized elderly patients is high, and is associated with the diagnoses of renal failure, liver disease and osteoarthritis, with a higher comorbidity and especially with a poorer functional capacity (AU)