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Understanding the origin of the strong difference of electrical parameters between as grown and annealed undoped ZnO films prepared at a temperature range of 100–200 °C by thermal atomic layer deposition is essential for their future applications. In this paper, we show that the conductivity drop by up to 4 orders of magnitude as effect of post-growth annealing is accompanied by multiple simultaneous effects like a two orders of magnitude decrease of hydrogen impurity content, a strong width reduction of the luminescence peaks, and an increase of crystallite sizes influencing the carrier scattering. We show that a level of structural and optical improvement as well as the final electrical parameters of annealed films strongly depend on the previously employed growth temperature, which is related to transition from oxygen- to zinc-rich conditions influencing a type and concentration of native point defects. The growth temperature does not only influence the bandgap energy but also the binding energies of existing donors and the relative ratio between the number of donors and acceptors; hence, it determines the final electrical characteristics of the films. This means that electrical properties of undoped ZnO-atomic layer deposition films can be tuned by native defects engineering. [ABSTRACT FROM AUTHOR]

Background and Study Aims: Endoscopic-ultrasound-guided trucut needle biopsy (EUS-TCB) has not been adequately evaluated in patients with submucosal tumors (SMTs). Patients and Methods: This prospective, uncontrolled study involving 49 consecutive patients with hypoechoic gastric SMTs (> or = 20 mm) evaluated diagnostic yield and 30-day morbidity of EUS-TCB, factors related to the success of EUS-TCB, and agreement between EUS-TCB and the surgical pathology diagnosis. Seventy-three percent of tumors were gastrointestinal stromal tumors (GIST). Results: Tumor tissue adequate for diagnosis was obtained by EUS-TCB in 31 patients (63 %; 95 %CI 49 % to 75 %). In the remaining cases, EUS-TCB provided no tissue (n = 11) or an insufficient amount (n = 7). Logistic regression analysis showed that tumor location on the lesser curvature of the stomach was the only independent predictor of obtaining diagnostic material [odds ratio (OR) 7.4; 95 %CI 1.9 to 28; P = 0.004]. The experience of the endosonographer, the size of the tumor, and the location of the tumor relative to the long axis of the stomach were not related to the success of the biopsy. Agreement between EUS-TCB and surgical pathology specimens in respect of the diagnosis and CD117 status was high (0.9, standard error 0.31; and 0.95, standard error 0.16, respectively); however, there was no correlation between the mitotic index as determined on EUS-TCB and that determined on the surgical pathology specimen (correlation coefficient, 0.08). There were two severe septic complications in 52 procedures (3.9 %; 95 %CI 0.3 % to 14 %). Conclusions: The diagnostic yield of EUS-TCB in patients with gastric SMTs was moderate. Tissue samples were too small to reliably determine the mitotic index. Antibiotic prophylaxis should be considered because of possible septic complications. [ABSTRACT FROM AUTHOR]

Our work suggests that the forces that govern protein folding exert a profound effect in determining how genotypes are translated into phenotypes, and that this has a strong effect on the evolutionary process in diverse organisms. The role of Hsp90 in chaperoning metastable signal transducers places it in a unique position to couple environmental contingencies to the evolution of new traits. By both buffering and potentiating genotypic changes, it affects oncogenic transformation, morphogenesis, and acquisition of drug resistance. Most recently, we used Saccharmoyces cerevisiae to uncover the specific genetic polymorphisms that underlie phenotypes revealed and concealed by Hsp90. Another line of work involves new types of hereditary elements (prions), which produce changes in phenotype through a heritable, self-perpetuating change in protein conformation. One yeast prion [PSI] is formed from an inactive, misfolded translation-termination factor, Sup35. Misfolded Sup35 protein results in the read-through of stop codons. This uncovers previously hidden genetic variation in a sudden, stepwise fashion by turning on the expression of previously silent regions of the genome located downstream of stop codons. [PSI] and a host of other newly discovered prions provide plausible mechanisms for allowing genetic diversity and fluctuating environments to fuel the pace of evolutionary change., doi: 10.1139/O09-905 S. Lindquist, D. Jarosz, S. Alberti, R. Halfmann, and J. Tyedmers Department of Biology, and Massachusetts Institute of Technology, Whitehead Institute for Biomedical Research, Howard Hughes Medical Institute, [...]

A series of 20 patients with 24 squamous cell papillomas of the esophagus are presented. Nonspecific symptoms not directly connected with esophageal disorders were the reason for esophagoscopy. Clinical findings, treatment, and follow-up of the patients in the context of the world literature review of 141 cases reported to date, are discussed. [ABSTRACT FROM AUTHOR]

Abstract Background Gastrointestinal stromal tumours (GISTs) represent a heterogeneous group of tumours of mesenchymal origin characterized by gain-of-function mutations in KIT or PDGFRA of the type III receptor tyrosine kinase family. Although mutations in either receptor are thought to drive an early oncogenic event through similar pathways, two previous studies reported the mutation-specific gene expression profiles. However, their further conclusions were rather discordant. To clarify the molecular characteristics of differentially expressed genes according to GIST receptor mutations, we combined microarray-based analysis with detailed functional annotations. Methods Total RNA was isolated from 29 frozen gastric GISTs and processed for hybridization on GENECHIP® HG-U133 Plus 2.0 microarrays (Affymetrix). KIT and PDGFRA were analyzed by sequencing, while related mRNA levels were analyzed by quantitative RT-PCR. Results Fifteen and eleven tumours possessed mutations in KIT and PDGFRA, respectively; no mutation was found in three tumours. Gene expression analysis identified no discriminative profiles associated with clinical or pathological parameters, even though expression of hundreds of genes differentiated tumour receptor mutation and expression status. Functional features of genes differentially expressed between the two groups of GISTs suggested alterations in angiogenesis and G-protein-related and calcium signalling. Conclusion Our study has identified novel molecular elements likely to be involved in receptor-dependent GIST development and allowed confirmation of previously published results. These elements may be potential therapeutic targets and novel markers of KIT mutation status.

Background: Gastrointestinal stromal tumours (GISTs) represent a heterogeneous group of tumours of mesenchymal origin characterized by gain-of-function mutations in KIT or PDGFRA of the type III receptor tyrosine kinase family. Although mutations in either receptor are thought to drive an early oncogenic event through similar pathways, two previous studies reported the mutation-specific gene expression profiles. However, their further conclusions were rather discordant. To clarify the molecular characteristics of differentially expressed genes according to GIST receptor mutations, we combined microarray-based analysis with detailed functional annotations.Methods: Total RNA was isolated from 29 frozen gastric GISTs and processed for hybridization on GENECHIP HG-U133 Plus 2.0 microarrays (Affymetrix). KIT and PDGFRA were analyzed by sequencing, while related mRNA levels were analyzed by quantitative RT-PCR.Results: Fifteen and eleven tumours possessed mutations in KIT and PDGFRA, respectively; no mutation was found in three tumours. Gene expression analysis identified no discriminative profiles associated with clinical or pathological parameters, even though expression of hundreds of genes differentiated tumour receptor mutation and expression status. Functional features of genes differentially expressed between the two groups of GISTs suggested alterations in angiogenesis and G-protein-related and calcium signalling.Conclusion: Our study has identified novel molecular elements likely to be involved in receptor-dependent GIST development and allowed confirmation of previously published results. These elements may be potential therapeutic targets and novel markers of KIT mutation status. [ABSTRACT FROM AUTHOR]

The molecular beam epitaxy (MBE) technique is renowned as the most suitable for the growth of high-quality crystalline materials and nanostructures such as GaAs. However, once established, optimal growth parameters required for repeatability of top-quality structures may be easily lost as MBE is highly sensitive to any changes in the system. Especially, routine servicing procedures, which include any activity which requires unsealing of the growth chamber, are devastating for developed growth parameters and force the necessity of recalibration. In this work, we present the process of growth parameter pre-optimization for obtaining homoepitaxial GaAs layers after servicing and restarting the MBE system. Namely, we present how each step of reestablishing optimal growth condition influences various characteristics of obtained GaAs layers. Those include in situ, structural, and spectral measurement techniques. An additional aspect was to compare the optimal conditions for the growth of homoepitaxial GaAs layers from two growth campaigns in which the main difference is the addition of an ion pump and increasing the temperature gradient on the Ga cell., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

We demonstrate strain-balanced InAs/AlSb type-II superlattices (T2SL) grown on GaSb substrates employing two kinds of interfaces (IFs): AlAs-like IF and InSb-like IF. The structures are obtained by molecular beam epitaxy (MBE) for effective strain management, simplified growth scheme, improved material crystalline quality, and improved surface quality. The minimal strain T2SL versus GaSb substrate can be achieved by a special shutters sequence during MBE growth that leads to the formation of both interfaces. The obtained minimal mismatches of the lattice constants is smaller than that reported in the literature. The in-plane compressive strain of 60-period InAs/AlSb T2SL 7ML/6ML and 6ML/5ML was completely balanced by the applied IFs, which is confirmed by the HRXRD measurements. The results of the Raman spectroscopy (measured along the direction of growth) and surface analyses (AFM and Nomarski microscopy) of the investigated structures are also presented. Such InAs/AlSb T2SL can be used as material for a detector in the MIR range and, e.g., as a bottom n-contact layer as a relaxation region for a tuned interband cascade infrared photodetector.

The article presents a systematic study of Sb-doped Zn 1-x Mg x O layers, with various concentrations of Mg, that were successfully grown by plasma-assisted MBE on polar a - and c -oriented and non-polar r -oriented sapphire substrates. X-ray diffraction confirmed the polar c -orientation of alloys grown on c -and a -oriented sapphire and non-polar structures grown on r -oriented substrates. A uniform depth distribution of the Sb dopant at level of 2 × 10 20 cm -3 was determined by SIMS measurements. Raman spectroscopy revealed the presence of Sb-related modes in all samples. It also showed that Mg alloying reduces the compressive strain associated with Sb doping in ZnO. XPS analysis indicates that the chemical state of Sb atoms in ZnMgO is 3+, suggesting a substitutional position of Sb Zn , probably associated with two V Zn vacancies. Luminescence and transmission spectra were measured to determine the band gaps of the Zn 1-x Mg x O layers. The band gap energies extracted from the transmittance measurements differ slightly for the a , c , and r substrate orientations, and the differences increase with increasing Mg content, despite identical growth conditions. The differences between the energy gaps, determined from transmission and PL peaks, are closely correlated with the Stokes shift and increase with the Mg content in the analyzed series of ZnMgO layers.

Background: Cerebral blood flow (CBF) can be related to the risk of occurrence of neurological symptoms. Well-developed collateral circulation is a good prognostic factor in patients with cerebrovascular disease. Understanding the mechanisms of collateral circulation may be important in the diagnosis, treatment, and monitoring in this group of patients. The aim of this study covered the assessment of CBF in patients with 70−99% Internal carotid artery (ICA) stenosis, focusing on the circulation pathways and flow volume in extracranial arteries. Materials and methods: 53 patients with 70−99% ICA stenosis (mean age 73.4 ± 7 years old; 17 female, mean age 73.9 ± 7.5 years old; 36 male, mean age 73.2 ± 6.8 years old) were included in the study. In all patients a Doppler ultrasound (DUS) examination, measuring blood flow volume in the internal carotid artery (ICA), external carotid artery (ECA), and vertebral artery (VA), was performed. The cerebral blood flow (CBF) was compared to the previously reported CBF values in the healthy population > 65 years old. Results: Among the study groups three subgroups with flow differences were identified: patients with elevated CBF (significant volumetric flow compensation—26/53, 49%), patients with CBF similar to (mild compensation—17/53, 32%), and patients with CBF lower than (no compensation—10/53, 19%) the healthy, equally aged population. The percentage of patients with significant volumetric flow compensation was the highest in age groups 65−69 years old (62.5%) and >80 years old (60%). In the oldest age group (>80 years old) no patients without flow compensation (0%) were observed. The level of compensation depends on the number of the arteries with compensatory increased flow. In patients with significant volumetric flow compensation, the compensatory increased flow was observed, on average, in 3.31 arteries, in the mild compensation group—in 2.18 arteries, and in the no compensation group only in 1 artery. ICA plays the most important role in the volumetric flow compensation—the increase in the flow volume, in comparison to the reference values, was between 116.7 mL/min and 251.9 mL/min (in the ECA 57.6 mL/min−110.4 mL/min; in the VA 73.9 mL/min−104.9 mL/min). The relative flow increase was highest in the VA: 215−246%, then in the ECA: 163−206%, and finally in the ICA: 148.6−192%. The increased flow was most commonly observed in the VA—57 arteries, in second place in the ECA—42 arteries, and ICA—31 arteries. In patients with unilateral ICA stenosis, the volumetric flow increase was stated more frequently in the ipsilateral ECAs then in the contralateral ones (23 vs. 14). In the VA the opposite tendency was observed (29 contralateral vs. 23 ipsilateral). The ability of volumetric flow compensation decreased significantly with increasing age. Conclusions: Understanding the mechanisms of collateral circulation and their assessment in Doppler ultrasonography may provide a novel and easily accessible tool of identifying and monitoring patients with cerebrovascular disease., Competing Interests: The authors declare no conflict of interest.

In this paper, the photoluminescence spectra of excitons in ZnO/ZnMgO/ZnO double asymmetric quantum wells grown on a-plane Al2O3 substrates with internal electric-field bands structures were studied. In these structures, the electron and the hole in the exciton are spatially separated between neighbouring quantum wells, by a ZnMgO barrier with different thickness. The existence of an internal electric field generates a linear potential and, as a result, lowers the energy of quantum states in the well. For the wide wells, the electrons are spatially separated from the holes and can create indirect exciton. To help the understanding of the photoluminescence spectra, for single particle states the 8 k·p for wurtzite structure is employed. Using these states, the exciton in the self-consistent model with 2D hydrogenic 1s-like wave function is calculated.

The rocksalt structure of ZnO has a very promising bandgap for optoelectronic applications. Unfortunately, this high-pressure phase is unstable under ambient conditions. This paper presents experimental results for rocksalt-type ZnO/MgO superlattices and theoretical considerations of the critical thickness of Mg x Zn 1-x O layers. The correlations between the layer/spacer thickness ratio, elastic strain, chemical composition, and critical thickness are analyzed. The Matthews and Blakeslee model is revisited to find analytic conditions for the critical layer thickness resulting in phase transition. Our analysis shows that due to the decrease in misfit stresses below some critical limit, the growth of multiple quantum wells composed of rocksalt ZnO layers and MgO spacers is possible only for very large layer/spacer thickness ratios.

Background: This retrospective case series aims to evaluate the efficacy of the Perclose ProGlide system for postoperative hemostasis following aortic stent-graft insertion., Material and Methods: A prospectively maintained database of patients with a minimum follow-up of 12 months following percutaneous aortic procedures was interrogated. Preprocedural computed tomography (CT) scans were reviewed to assess existing stenosis in the common femoral artery (CFA). Arteries with an estimated stenosis of greater than 25% on visual inspection underwent quantification using multiplanar and curved planar reformation. The preoperative and 1-year follow-up CTs of these patients were assessed for change in stenosis. Analysis was performed by 2 independent reviewers, with senior authors reviewing any discrepancies., Results: One hundred forty-two endovascular aortic aneurysm repairs (EVARs) were performed. The ProGlide system was used in 235 arteries, yielding a high success rate in obtaining postprocedural hemostasis (94%). There were 13 postprocedural access-related complications, including 5 patients requiring surgical closure due to inadequate seal. Two patients required thrombectomy due to distal embolization. One patient required CFA endarterectomy at 6 months for the treatment of preexisting short distance claudication. Vessel analysis was performed in 31 arteries. Mean preoperative stenosis was 32% (range: 20%-57%). Mean postoperative stenosis was 32% (21%-57%). No significant change in degree of stenosis was detected (defined as a 5% change)., Conclusions: The ProGlide system yielded a high success rate in obtaining postoperative hemostasis with low rate of conversion to surgical closure and low complication rates. There was no evidence of worsening vessel stenosis in arteries with preprocedural stenotic disease., Level of Evidence: Level 4, Case Series.

While synthesis methods for pure ZnO nanostructures are well established, an efficient technique for the growth of ZnO-based nanowires or microrods that incorporate any type of quantum structure is yet to be established. Here, we report on the fabrication and optical properties of axial Zn1-xMgxO/ZnO/Zn1-xMgxO quantum wells that were deposited by molecular beam epitaxy on ZnO microrods obtained using a hydrothermal method. Using the emission energy results found in cathodoluminescence measurements and the results of a numerical modeling process, we found the quantum well width to be 4 nm, as intended, at the growth stage. The emission of quantum well-confined excitons persists up to room temperature. We used the fabricated structures to determine the carrier diffusion length (>280 nm) in ZnO using spatially resolved cathodoluminescence. The micro-photoluminescence results suggest an increase in the electron-phonon coupling strength with increasing microrod size.

The fourth EMBO-sponsored conference on Experimental Approaches to Evolution and Ecology Using Yeast and Other Model Systems (https://www.embl.de/training/events/2016/EAE16-01/), was held at the EMBL in Heidelberg, Germany, October 19-23, 2016. The conference was organized by Judith Berman (Tel Aviv University), Maitreya Dunham (University of Washington), Jun-Yi Leu (Academia Sinica), and Lars Steinmetz (EMBL Heidelberg and Stanford University). The meeting attracted ~120 researchers from 28 countries and covered a wide range of topics in the fields of genetics, evolutionary biology, and ecology with a unifying focus on yeast as a model system. Attendees enjoyed the Keith Haring inspired yeast florescence microscopy artwork (Figure 1), a unique feature of the meeting since its inception, and the one-minute flash talks that catalyzed discussions at two vibrant poster sessions. The meeting coincided with the 20th anniversary of the publication describing the sequence of the first eukaryotic genome, Saccharomyces cerevisiae (Goffeau et al. 1996). Many of the conference talks focused on important questions about what is contained in the genome, how genomes evolve, and the architecture and behavior of communities of phenotypically and genotypically diverse microorganisms. Here, we summarize highlights of the research talks around these themes. Nearly all presentations focused on novel findings, and we refer the reader to relevant manuscripts that have subsequently been published., (Copyright © 2017, G3: Genes, Genomes, Genetics.)

Cancer cells have the unusual capacity to limit the cost of the mutation load that they harbor and simultaneously harness its evolutionary potential. This property fuels drug resistance, a key failure mode in oncogene-directed therapy. However, the factors that regulate this capacity might also provide an Achilles' heel that could be exploited therapeutically. Recently, insight has come from a seemingly distant field: protein folding. It is now clear that protein homeostasis broadly supports malignancy and fuels the rapid evolution of drug resistance. Among protein homeostatic mechanisms that influence cancer biology, the essential ATP-driven molecular chaperone heat-shock protein 90 (Hsp90) is especially important. Hsp90 catalyzes folding of many proteins that regulate growth and development. These "client" kinases, transcription factors, and ubiquitin ligases often play critical roles in human disease, especially cancer. Studies in a wide range of systems-from single-celled organisms to human tumor samples-suggest that Hsp90 can broadly reshape the map between genotype and phenotype, acting as a "capacitor" and "potentiator" of genetic variation. Indeed, it has likely done so to such a degree that it has left an impress on diverse genome sequences. Hsp90 can constitute as much as 5% of total protein in transformed cells and increased levels of heat-shock activation correlate with poor prognosis in breast cancer. These findings and others have motivated a flurry of interest in Hsp90 inhibitors as cancer therapeutics, which have met with rather limited success as single agents, but may eventually prove invaluable in limiting the emergence of resistance to other chemotherapeutics, both genotoxic and molecularly targeted. Here, we provide an overview of Hsp90 function, review its relationship to genetic variation and the evolution of new traits, and discuss the importance of these findings for cancer biology and future efforts to drug this pathway., (© 2016 Elsevier Inc. All rights reserved.)

Objective: The diagnosis of celiac disease (CD) in patients with different autoimmune diseases including Graves disease (GD) remains a challenge. The aims of our study were to: (1) assess the prevalence of CD in Polish patients with GD and (2) evaluate the prevalence of CD in the subgroups of patients with GD divided on the basis of clinical and human leukocyte antigen (HLA) typing criteria., Methods: The prospective study was conducted at an academic referral center. The study groups consisted of consecutive, euthyroid patients with GD (n = 232) and healthy volunteers without autoimmune thyroid diseases (n = 122). The diagnosis of CD was based on elevated immunoglobulin A autoantibodies to the enzyme tissue transglutaminase (IgA-TTG) and small intestine biopsy findings., Results: CD was diagnosed in 8 patients with GD (3.4%) and 1 healthy volunteer (0.8%). The development of CD in patients with GD was strongly associated with HLA-DQ2 haplotype (as predicted from linkage disequilibria, 14.6% vs. 1.5%, P = .009; odds ratio [OR] = 11.3; 95% confidence interval [CI] 1.3-252.7): 6 patients with CD carried HLA-DRB1(*)03, 1 carried an HLA-DRB1(*)04 allele, and 1 had an HLA-DRB1(*)07/(*)11 genotype. Multivariate analysis showed independent associations between CD and early GD onset (P = .014, OR = 9.6), autoimmunity in family (P = .029, OR = 6.3) and gastroenterologic symptoms (P = .031, OR = 8.1)., Conclusions: The results of our study suggest that serologic screening for CD may be considered in GD patients (1) with the HLA alleles typical for CD, (2) with an early onset of GD, or (3) a family history of autoimmunity. Moreover, the diagnosis of CD should be explored in euthyroid GD patients with nonspecific gastrointestinal symptoms.

Introduction: It has been reported in coronary heart disease (CHD) patients that mortality is inversely associated with body mass index (BMI), and directly associated with waist circumference (WC). The purpose of this study was to examine the association of the general obesity parameter (BMI) and the adipose tissue discriminator (WC) with cardiovascular (CV) risk in patients with CHD established by coronary angiography., Objectives: 1345 subjects with CHD were included in the PROGNOSIS (Prognostic Value of Ambulatory Blood Pressure Monitoring in Patients with Coronary Artery Disease Confirmed by Angiography) study., Patients and Methods: A multivariate Cox proportional regression model adjusted for potential confounders was used to assess the relative risk of total and CV mortality according to the parameters of general obesity (BMI) and adipose tissue distribution (WC).The mean age of subjects was 63.2 ± 9.2 years, and 57% were men. Results. There was direct relationship between WC and both total mortality [hazard ratio, HR = 1.03 (95% CI 1.01-1.10), p < 0.01] and CV mortality [HR = 1.03 (95% CI 1.01-1.07), p < 0.03], but an inverse relationship between BMI and both total mortality [HR = 0.91 (95% CI 0.86-0.98), p < 0.03] and CV mortality [HR = 0.97 (95% CI 0.87-0.99), p < 0.05]. After combining WC with BMI, the group of subjects with BMI < 25 kg/m(2) and WC ≥ 104 cm had the highest rates of both total and CV mortality of all CHD patients., Conclusions: Assessment based on a combination of WC and BMI is superior to assessment based on a separate estimation of these parameters in both total and CV mortality risk evaluation.

A total proctocolectomy with ileal pouch-anal anastomosis (IPAA) is considered the surgery of choice for definitive management of familial adenomatous polyposis (FAP) and some patients with ulcerative colitis (UC). However, this surgical treatment is often associated with pouchitis, a long-term complication that occurs mostly in UC patients. The purpose of this study was to better define the molecular background of pouchitis. A microarray-based survey was performed using pouch mucosal samples collected from 28 and 8 patients undergoing surgery for UC and FAP, respectively. There were 4,770 genes that significantly differentiated uninflamed from inflamed mucosal samples, and their functional features were represented mostly by metabolic and cell proliferation pathways. In contrast, functional analyses of aberrantly expressed genes between UC and FAP samples, irrespective of mucosal inflammation status, revealed multiple pathways and terms that were linked to changes in immune response. Interestingly, the comparison of uninflamed UC and FAP samples identified a set of 29 altered probe sets, including an inflammation-related transcript encoding a Charcot-Leyden crystal (CLC) protein. The most distinct changes in gene expression profiles differentiating uninflamed UC and FAP pouch mucosal samples were attributed to the Gene Ontology category innate immune response. Our study confirmed that alterations in immune responses can be found between patients who underwent surgery for UC and FAP, independent of the pouch inflammation status. This observation may be important when managing IPAA patients.