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The effect of different milling conditions on the formation of Fe-doped TiO2 powders by mechanical alloying was investigated by Mössbauer spectrometry. The milling conditions investigated were ball to powder weight ratio, milling time, rotation velocity of supporting disc, and the type of starting reactive iron and its concentration. X-ray diffraction shows that high energy mechanical milling of undoped anatase TiO2 induce the anatase to rutile phase transformation via high pressure srilankite. Mössbauer spectra for the majority of the doped samples were decomposed into one sextet and one or two doublets. The sextets was attributed to the presence of α-Fe or hematite impurities. The doublets were assigned to Fe3 + incorporated in the TiO2 structure, and to the Fe2 + located either at the surface or the interstitial sites of TiO2. A greater incorporation of Fe in the TiO2 structure was observed when samples were prepared from hematite instead of α-Fe. [ABSTRACT FROM AUTHOR]

The mechanochemical treatment of the α-Fe2O3 (hematite) powder in air and a dispensing liquid (ethanol), using a planetary ball mill was performed. The influence of the atmosphere and the milling time in α-Fe2O3 transformation was investigated. X ray difraction (XRD) arid Mössbauer measurements showed partial transformation from α-Fe2O3 to γ-Fe2O3 (maghemite) for prolonged milling time in air, while only one α-Fe2O3 phase was obtained for the milling using ethanol. Lattice parameters and particles size has been calculated from the XRD patterns for the different times and milling conditions. [ABSTRACT FROM AUTHOR]

Fe-doped TiO2 powders were obtained by mechanical alloying. The starting materials were anatase TiO2 and metallic iron (α-Fe). The influence of different milling conditions such as: ball to powder weight ratio (20:1, 40:1); milling time (6, 12, 18 and 24 hours); rotation velocity of supporting disc (250 and 390 rpm) and dopant concentration ( 1, 4 and 8 at%) on the structural and magnetic properties were investigated.. All experiments were performed at atmospheric conditions. The milled powders were characterized by X-Ray diffraction (XRD) using Rietveld refinement and room temperature Mössbauer spectrometry. Mössbauer spectra reveal the presence of Fe2+ and Fe3+ states as well as α-Fe in samples obtained from metallic iron. The Fe3+ contribution could be attributed to Fe incorporated in the TiO2 structure and the Fe2+ can be assigned to surface ferrous ions in the TiO2[3]. [ABSTRACT FROM AUTHOR]

We have derived the Melchers' mathematical model of the oxygen diffusion across the rust layer formed on the surface of the steels submitted to total immersion, by a most fundamental principle: the Planck-Nersnt law. To achieve it, we have neglected the convection and migration of the oxygen molecules, and we have assumed both that this problem is 1-D and that oxygen consumption, due to chemical reactions, can only occur at the interface between the metallic surface and the rust. Furthermore, we have experimentally determined an α value for Melchers's model, which accounts for the amount of iron coming from the steel which is converted into adherent rust. [ABSTRACT FROM AUTHOR]

Background and study aims  Probe-based confocal laser endomicroscopy (pCLE) can provide high magnification to evaluate chronic atrophic gastritis (CAG), but the current pCLE criteria are qualitative and prone to variability. We aimed to propose a quantitative CAG criterion based on pCLE to distinguish non-atrophic gastritis (NAG) from CAG. Patients and methods  This observational, exploratory pilot study included patients with NAG and CAG evaluated via esophagogastroduodenoscopy, pCLE, and histology. We measured the gastric glands density, gastric gland area, and inter-glandular distance during pCLE. Results  Thirty-nine patients (30/39 with CAG) were included. In total, 194 glands were measured by pCLE, and 18301 were measured by histology, with a median of five glands per NAG patient and 4.5 per CAG patient; pCLE moderately correlate with histology (rho = 0.307; P  = 0.087). A gland area of 1890-9105 µm 2 and an inter-glandular distance of 12 to 72 µm based on the values observed in the NAG patients were considered normal. The proposed pCLE-based CAG criteria were as follows: a) glands density < 5; b) gland area < 1/16 the pCLE field area (< 1890 µm 2 ) or > 1/4 the pCLE field area (> 9105 µm 2 ); or c) inter-glandular distance < 12 or > 72 µm; CAG was diagnosed by the presence of at least one criterion. The proposed criteria discriminated CAG with a ranged sensitivity of 76.9 % to 92.3 %, a negative predictive value of 66.6 % to 80.0 %, and 69.6 % to 73.9% accuracy. Conclusions  The proposed pCLE criteria offer an accurate quantitative measurement of CAG with high sensitivity and excellent interobserver agreement. Larger studies are needed to validate the proposed criteria., Competing Interests: Competing interests Dr. Robles-Medranda is a key opinion leader and consultant for Pentax Medical, Boston Scientific, G-tech Medical Supply, and MD Consulting Group., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/).)

Background: Cyanoacrylate (CYA) injection can be performed using a standard upper endoscopy technique or under endoscopic ultrasound (EUS) guidance alone or in combination with coils. There is little information available on the economic impact of these treatment methods., Aim: To compare the cost-effectiveness of treating gastric varices by CYA injection via upper endoscopy vs coils plus CYA guided by EUS., Methods: This was an observational, descriptive, and retrospective study. Patients were allocated into two groups: A CYA group and coils plus CYA group. The baseline characteristics were compared, and a cost analysis was performed., Results: Overall, 36 patients were included (19 in the CYA group and 17 in the coils + CYA group). All patients in the CYA group had acute bleeding. They underwent a higher mean number of procedures (1.47 vs 1, P = 0.025), and the mean volume of glue used was 2.15 vs 1.65 mL, P = 0.133. The coils + CYA group showed a higher technical success rate (100% vs 84.2%), with a complication rate similar to the CYA group. The majority of CYA patients required hospitalization, and although the mean total per procedure cost was lower (United States $ 1350.29 vs United States $ 2978), the mean total treatment cost was significantly different (United States $ 11060.89 for CYA vs United States $ 3007.13 for coils + CYA, P = 0.03)., Conclusion: The use of EUS-guided coils plus cyanoacrylate is more cost-effective than cyanoacrylate injection when the total costs are evaluated. Larger, randomized trials are needed to validate the cost-effectiveness of the EUS-guided approach to treat gastric varices., Competing Interests: Conflict-of-interest statement: Carlos Robles-Medranda is a key opinion leader and consultant for Pentax Medical, Boston Scientific, G-tech medical supply and MD consulting group. The other authors have nothing to disclose., (©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Several metastrongyloid lungworms are unreported pathogens in Colombia. Angiostrongylus vasorum and Crenosoma vulpis target the cardiopulmonary system of domestic and wild canids. Aelurostrongylus abstrusus and Troglostrongylus brevior infect felids and considering that six wild felid species exist in Colombia, knowledge of feline lungworm infections is important for their conservation. The zoonotic metastrongyloids Angiostrongylus costaricensis and Angiostrongylus cantonensis can cause severe gastrointestinal and neurological diseases. Angiostrongylus costaricensis has been reported in Colombia, while Ang. cantonensis is present in neighbouring countries. Research on the epidemiology of metastrongyloids in Colombia and South America more broadly requires evaluating the role that gastropods play as intermediate hosts in their life cycles. This study assessed the prevalence of metastrongyloid larvae in populations of the invasive giant African snail, Lissachatina fulica, in Colombia., Methodology/principal Findings: A total of 609 Lissachantina fulica were collected from 6 Colombian municipalities. The snails were then cryo-euthanized, artificially digested and the sediments examined microscopically for the presence of metastrongyloid larvae. Based on morphological characteristics 53.3% (56/107) of the snails from Puerto Leguízamo (Department of Putumayo) were infected with Ael. abstrusus larvae, 8.4% (9/107) with Ang. vasorum larvae, 6.5% (7/107) with T. brevior larvae and 5.6% (6/107) with C. vulpis larvae, being the region with highest prevalences of the four species. Snails from Andes (Department of Antioquia) and Tulúa (Department of Valle del Cauca) were positive for Ang. vasorum larvae with a prevalence of 4.6 (11/238) and 6.3% (4/64), respectively. Species identifications were confirmed by PCR and sequencing., Conclusions/significance: This epidemiological survey reports for first time the presence of Ael. abstrusus, T. brevior, C. vulpis and Ang. vasorum in L. fulica in a number of regions of Colombia., Competing Interests: The authors have declared that no competing interests exist.

Background: The aim of this study was to propose a novel, comprehensive, macroscopic classification for bile duct lesions., Methods: A two-stage protocol was designed. In Stage I, a retrospective study (September 2013 to September 2015) of patients with bile duct lesions detected by peroral cholangioscopy (POCS) was performed. A total of 315 images with at least 6 months of follow-up were recorded, analyzed, and correlated to histology, and were classified as non-neoplastic (one of three types, 1 - 3) or neoplastic (one of four types, 1 - 4) based on morphological and vascular patterns. In Stage II, a prospective, nonrandomized, double-blind study was performed from December 2015 to December 2016 to validate the proposed classification. Sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively), and positive and negative likelihood ratios (LR + and LR - , respectively) were calculated (gold standard: 6-month follow-up). Inter- and intraobserver agreement (kappa value, κ) among experts and non-experts were calculated., Results: 171 patients were included (65 retrospective; 106 prospective). In Stage I, 28/65 cases were neoplastic and 37 /65 were non-neoplastic, according to the final diagnosis. In Stage II, 56/106 were neoplastic with a sensitivity, specificity, PPV, NPV, LR + , and LR - for neoplastic diagnosis of 96.3 %, 92.3 %, 92.9 %, 96 %, 12.52, and 0.04, respectively. The proposed classification presented high reproducibility among observers, for both neoplastic and subtypes categories. However, it was better for experts (κ > 80 %) than non-experts (κ 64.7 % - 81.9 %)., Conclusion: The novel classification system could help physicians to distinguish non-neoplastic from neoplastic bile duct lesions., Competing Interests: None, (© Georg Thieme Verlag KG Stuttgart · New York.)

The muscleblind-like (MBNL) family of proteins are key developmental regulators of alternative splicing. Sequestration of MBNL proteins by expanded CUG/CCUG repeat RNA transcripts is a major pathogenic mechanism in the neuromuscular disorder myotonic dystrophy (DM). MBNL1 contains four zinc finger (ZF) motifs that form two tandem RNA binding domains (ZF1-2 and ZF3-4) which each bind YGCY RNA motifs. In an effort to determine the differences in function between these domains, we designed and characterized synthetic MBNL proteins with duplicate ZF1-2 or ZF3-4 domains, referred to as MBNL-AA and MBNL-BB, respectively. Analysis of splicing regulation revealed that MBNL-AA had up to 5-fold increased splicing activity while MBNL-BB had 4-fold decreased activity compared to a MBNL protein with the canonical arrangement of zinc finger domains. RNA binding analysis revealed that the variations in splicing activity are due to differences in RNA binding specificities between the two ZF domains rather than binding affinity. Our findings indicate that ZF1-2 drives splicing regulation via recognition of YGCY RNA motifs while ZF3-4 acts as a general RNA binding domain. Our studies suggest that synthetic MBNL proteins with improved or altered splicing activity have the potential to be used as both tools for investigating splicing regulation and protein therapeutics for DM and other microsatellite diseases.

Introduction: The controversy over the presence of empathic decline within the course in students of medicine, dentistry and health sciences in general, has not fully been studied. This controversy could be partially solved if massive studies of empathy levels are made in similar cultural, social and economic contexts., Material and Methods: Empathy levels within the course were studied in eighteen dental schools from six countries in Latin America (2013). The mean of the empathy levels were used to study the behavior between first and fifth academic years. The values of empathy levels within the course were observed by applying the Jefferson Scale of Physician Empathy, the Spanish version. All these studies were cross-sectional. The value of means observed, were subjected to regression studies and further adjustment curves were obtained and the coefficient of determination were calculated., Results: Six different models of behavior were observed, which found that five of them suffer empathic decline within the course, but with different final results: in some the decline persists until the fifth academic year and in others, this decline 'recovers' persistently until the fifth academic year. The sixth model is characterized by a constant and persistent increase of levels of empathy within the course until the last academic year., Discussion: There are six different models for the behavior of means of levels of empathy within the course evaluated by a common methodology in eighteen dental schools from six countries of Latin America. These findings support the existence of variability of empathic response and a comprehensive approach is needed to find the causes that give rise to this variability., Conclusion: In dental students of Latin America, there is variability in the behavior of the distribution in means between the academic years of the dentistry schools examined in this study.

Transcription of expanded microsatellite repeats is associated with multiple human diseases, including myotonic dystrophy, Fuchs endothelial corneal dystrophy, and C9orf72-ALS/FTD. Reducing production of RNA and proteins arising from these expanded loci holds therapeutic benefit. Here, we tested the hypothesis that deactivated Cas9 enzyme impedes transcription across expanded microsatellites. We observed a repeat length-, PAM-, and strand-dependent reduction of repeat-containing RNAs upon targeting dCas9 directly to repeat sequences; targeting the non-template strand was more effective. Aberrant splicing patterns were rescued in DM1 cells, and production of RAN peptides characteristic of DM1, DM2, and C9orf72-ALS/FTD cells was drastically decreased. Systemic delivery of dCas9/gRNA by adeno-associated virus led to reductions in pathological RNA foci, rescue of chloride channel 1 protein expression, and decreased myotonia. These observations suggest that transcription of microsatellite repeat-containing RNAs is more sensitive to perturbation than transcription of other RNAs, indicating potentially viable strategies for therapeutic intervention., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Oncology healthcare providers have an obligation to support cancer survivors, not just during active treatment, but also long after they have completed therapy. By providing survivorship care education and establishing programs using evidence-based practice, the specific needs and resources required to aid survivors in this new transition and journey can be identified. Survivors need to be guided, informed, and have their unique needs addressed.

Background: Recently there has been a large outbreak of Zika virus infections in Colombia, South America. The epidemic began in September 2015 and continued to April 2017, for the total number of Zika cases reported of 107,870. For those confirmed Zika cases, there were nearly 20,000 (18.5%) suspected to be pregnant women, resulting in 157 confirmed cases of microcephaly in newborns reported by their health government agency. There is a clear under-estimation of the total number of cases and in addition no prior publications have been published to demonstrate the clinical aspects of the Zika infection in Colombia. We characterized one Zika presentation to be able to compare and contrast with other cases of Zika infection already reported in the literature., Case Presentation: In this case report, we demonstrate congenital microcephaly at week 19 of gestation in a 34-year-old mother who showed symptoms compatible with Zika virus infection from Sincelejo, State of Sucre, in the Colombian Caribbean. Zika virus RNA was detected in the placenta using real-time reverse transcriptase polymerase chain reaction (RT-PCR). At week 25, the fetus weigh estimate was 770 g, had a cephalic perimeter of 20.2 cm (5th percentile), ventriculomegaly on the right side and dilatation of the fourth ventricle. At week 32, the microcephaly was confirmed with a cephalic perimeter of 22 cm, dilatation of the posterior atrium to 13 mm, an abnormally small cerebellum (29 mm), and an augmented cisterna magna. At birth (39 weeks by cesarean section), the head circumference was 27.5 cm, and computerized axial tomography (Siemens Corp, 32-slides) confirmed microcephaly with calcifications., Conclusion: We report a first case of maternal Zika virus infection associated with fetal microcephaly in Colombia and confirmed similar presentation to those observed previous in Brazil, 2015-2016.

Introduction: Despite advances in neonatal care between 20% and 63% of children with necrotizing enterocolitis (NEC) require surgery. The aim was correlation the risk factors of infants with NEC "IIB / IIIA / IIIB" Bell and the clinical, surgical and pathological findings., Method: In the children with diagnosis of NEC surgically treated, were analyzed of variables: clinical, surgical and pathological findings. We studied two groups: control (n=5) and NEC group (n=12). Comparisons were made between groups using the Mann-Whitney U- and the Spearman coefficient (r). To assess the risk of morbidity / mortality associated with the extent of intestinal resection we applied the Cox regression., Result: We found differences (p < 0.05) between control group and the NEC group regarding Bell, the mean height of villi, Chiu and the number of goblet cells. In the NEC group we find correlations (p < 0.05) from Bell, regarding Chiu (r = 0.761), resection of the colon (r = 0.687), pneumatosis / perforation (r = 1) and the mean height of villi (r = -0.878). The gut reseccion was at 26 cm (3-107). We observed a risk of 1.04 in the neonatal period (p > 0.05) of mortality or consequence post-enterocolitis associated with the extent of bowel resection., Conclusion: The decrease in the average height of villi, the highest level of microscopic intestinal injury and reduced goblet cell population contributes to a greater extent of intestinal resection, which favors the risk of death or developing consequence post-enterocolitis.

Trastuzumab and lapatinib provide clinical benefit to women with human epidermal growth factor receptor 2 (HER)-positive breast cancer. However, not all patients whose tumors contain the HER2 alteration respond. Consequently, there is an urgent need to identify new predictive factors for these agents. The aim of this study was to investigate the role of receptor tyrosine kinase signaling and phosphoinositide 3-kinase (PI3K)/AKT pathway activation in conferring resistance to trastuzumab and lapatinib. To address this question, we evaluated response to trastuzumab and lapatinib in a panel of 18 HER2-amplified cell lines, using both two- and three-dimensional culture. The SUM-225, HCC-1419, HCC-1954, UACC-893, HCC-1569, UACC-732, JIMT-1, and MDA-453 cell lines were found to be innately resistant to trastuzumab, whereas the MDA-361, MDA-453, HCC-1569, UACC-732, JIMT-1, HCC-202, and UACC-893 cells are innately lapatinib resistant. Lapatinib was active in de novo (SUM-225, HCC-1419, and HCC-1954) and in a BT-474 cell line with acquired resistance to trastuzumab. In these cells, trastuzumab had little effect on AKT phosphorylation, whereas lapatinib retained activity through the dephosphorylation of AKT. Increased phosphorylation of HER2, epidermal growth factor receptor, HER3, and insulin-like growth factor IR correlated with response to lapatinib but not trastuzumab. Loss of PTEN or the presence of activating mutations in PI3K marked resistance to trastuzumab, but lapatinib response was independent of these factors. Thus, increased activation of the PI3K/AKT pathway correlates with resistance to trastuzumab, which can be overcome by lapatinib. In conclusion, pharmacologic targeting of the PI3K/AKT pathway may provide benefit to HER2-positive breast cancer patients who are resistant to trastuzumab therapy.

The biochemical properties of the digestive alpha-amylase from Tecia solanivora larvae, an important and invasive insect pest of potato (Solanum tuberosum), were studied. This insect has three major digestive alpha-amylases with isoelectric points 5.30, 5.70 and 5.98, respectively, which were separated using native and isoelectric focusing gels. The alpha-amylase activity has an optimum pH between 7.0 and 10.0 with a peak at pH 9.0. The enzymes are stable when heated to 50 degrees C and were inhibited by proteinaceous inhibitors from Phaseolus coccineus (70% inhibition) and P. vulgaris cv. Radical (87% inhibition) at pH 6.0. The inhibitors present in an amaranth hybrid inhibited 80% of the activity at pH 9.0. The results show that the alpha-amylase inhibitor from amaranth seeds may be a better candidate to make genetically-modified potatoes resistant to this insect than inhibitors from common bean seeds.

Purpose: Recent studies suggest that HER-2/neu specifically promotes the invasive capacity of tumor cells by up-regulating secretion of the proteolytic enzyme, urokinase-type plasminogen activator (uPA), or its inhibitor, plasminogen activator inhibitor-1 (PAI-1), in colon and gastric cancer. It was the purpose of this study to: (a) evaluate the association between HER-2/neu and uPA and PAI-1 expression in a large primary breast cancer cohort; (b) perform the first multivariate analysis, including HER-2/neu, uPA, and PAI-1 in breast cancer; and (c) define the effect of HER-2/neu overexpression on uPA and PAI-1 expression in breast cancer cells., Experimental Design: HER-2/neu, uPA, and PAI-1 were measured as continuous variables by ELISA in primary breast cancer tissue extracts from 587 patients with clinical follow-up and analyzed for correlations with clinical outcome. Furthermore, a full-length human HER-2/neu cDNA was introduced into five human breast cancer cell lines to define the effects of HER-2/neu overexpression on uPA and PAI-1 expression. In addition, we tested whether HER-2/neu antibodies could reverse any given alteration of uPA and PAI-1 levels., Results: Our findings indicate a weak positive association between HER-2/neu and uPA (r = 0.147; P < 0.001) and no association between HER-2/neu and PAI-1 (r = 0.07; P = 0.085). HER-2/neu overexpression (> or =400 fmol/mg) and high levels of uPA/PAI-1 (> or =5.5 ng/mg and/or > or =14 ng/mg, respectively) were significantly associated with shorter disease-free survival (DFS; P < 0.001 and P = 0.003) and metastasis-free survival (MFS; P = 0.015 and P < 0.001). Multivariate analysis revealed prognostic independence between HER-2/neu and the uPA/PAI-1 axis for DFS and MFS. Both uPA and PAI-1 had no significant discriminatory effect among HER-2/neu-positive patients for DFS. The prognostic value of HER-2/neu overexpression for MFS, however, was significantly enhanced by elevated uPA expression (P = 0.053). Stable transfection of the HER-2/neu gene into multiple human breast cancer cell lines resulted in consistent down-regulation of uPA or PAI-1 expression. In addition, anti-HER-2/neu antibodies did not significantly affect uPA or PAI-1 expression in human cancer cell lines naturally overexpressing HER-2/neu., Conclusions: The present findings suggest that the invasive phenotype elicited by HER-2/neu overexpression in breast cancer is not a direct effect of uPA or PAI-1 expression. HER-2/neu and the uPA/PAI-1 axis have been shown to affect the invasive capacity of breast cancer independently. Determination of uPA can provide significant additional prognostic information for MFS in HER-2/neu-positive and -negative patients.