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Publicado 2020
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The concrete is not one hundred percent impermeable since the water that remains inside it causes its corrosion, in the case of reinforced concrete, exposed in an area of marine atmosphere, the sea salt mostly present in large particles of the marine spray, produce the reduction of the alkalinity of the concrete causing a rapid corrosion of the steel. There are buildings built in this marine area that have been designed without durability criteria, in which the use of pozzolanic materials is considered, for example, to fill the pores of the cement matrix and thus guarantee its impermeability. In the present study, the effect of clay brick powder (PLA) as a replacement for cement in concrete manufacturing is addressed, evaluating different characteristics of its components. The results indicate that pozzolanic activity and compressive strength increase, slump, voids content and the coeffi...
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Publicado 2016
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RESUMEN: La anquiloglosia es una anormalidad congénita relativamente común del frenillo lingual, que impide los movimientos adecuados de la lengua y causa disturbios motores en este órgano. Esta alteración ocurre en 0.02% al 4.8% de los recién nacidos y está asociado en un 25% a 60% de dificultades durante el amamantamiento. El propósito del presente reporte de caso es mostrar las aplicaciones del Sistema Láser de Diodo Infrarrojo (940nm) parasimplificar el abordaje quirúrgico de la anquiloglosia lingual en infantes y sus ventajas frente a la técnica convencional FRENECTOMY PROCEDURE IN INFANTS WITH LASER ABSTRACT Ankyloglossia is a relatively common congenital abnormality of the lingual frenum that prevents tonge movements and causes motor disturbances in this organ. This alteration occurs in 0.02% to 4.8% of newborns and associated with 25%...
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Publicado 2017
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This article discusses overweight and obesity and its implications as a huge public health problem in the world and in Peru. It is a problem with rapid growth in recent decades, particularly among younger age groups, and is related to changes in the living conditions of the population. Notable among these changes are the market’s massive growth and the consumption of ultra-processed products, which are gradually replacing natural and minimally processed foods in the population’s diet. The article argues that this growth is mainly due to two factors: the market`s lack of regulation for these ultra-processed products and the huge marketing machinery that encourages their consumption. Obesity is also related to the urbanization process. The latter has given rise to cities that prioritize motorized mobility at the expense of non-motorized transportation, with insufficient green areas and...
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Publicado 2020
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Simulation tools can be helpful for supporting implementation of livestock production systems and exploring ways of improvements. The aim of this paper is to present a support tool for implementation and evaluation of silvopastoral systems in the Peruvian Amazon Region. This approach is based on the design of a decision support model called Agrosilvopastoril v 19.1. It calculates livestock production using integrated information on climate, soil, crops, forestry, pastures and cattle herds collected from secondary sources and on-field work conducted at the Peruvian Northern Amazon Region. The model was tested to estimate carbon sequestration and enteric methane emissions in 10 has of silvopastures with different proportions of forest and pasture, showing an increase in carbon sequestration with a small reduction in the number of animals and similar methane emissions.
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Publicado 2021
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The Minifiber EC (MFEC) is a portable instrument for measuring the diameter of animal fibers. Its accuracy and precision have been estimated but by comparing its measurements with those of laboratory devices that had been calibrated on other devices in turn, not on a direct or primary measure of diameter. This work attempts to test direct measurements by gravimetry, Vernier mini caliper, microscope and the classic microprojector, using a non-deformable, high resistance synthetic fiber (Kevlar) for direct measurement. The MFEC instrument is calibrated with each mean fiber diameter obtained in direct measurements and its results are compared. The conclusions drawn are that it is possible to calibrate the MFEC instrument with direct measurements on Kevlar and measurement accuracy or tolerance of 0.28 microns is obtained. This indicates a very low biased mean fiber diameter measurement by MF...
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Purpose: O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation predicts the outcome and response to alkylating chemotherapy in glioblastoma. The aim of this study is to evaluate the prevalence of MGMT methylation in Peruvian glioblastoma cases. Patients and methods: We evaluated retrospectively 50 cases of resected glioblastoma during the period 2008-2013 at Instituto Nacional de Enfermedades Neoplasicas in Peru. Samples consisted of paraffin embedded and frozen tumour tissue. MGMT-promoter methylation status and the expression level of MGMT gene were evaluated by methylation-specific PCR and real-time PCR, respectively. Results: Unmethylated, methylated and partially methylated statuses were found in 54%, 20% and 26% of paraffin-embedded samples, respectively. Methylation status was confirmed in the Virgen de la Salud Hospital and frozen samples. There was an association be...
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Publicado 2021
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This work was supported by Proyecto CONCYTEC–Banco Mundial “Mejoramiento y Ampliación de los Servicios del Sistema Nacional de Ciencia Tecnología e Innovación Tecnológica” 8682-PE ( 104-2018-FONDECYT-BM-IADT-AV ).
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Publicado 2021
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Triple-negative breast tumours (TNBTs) make up 15-20% of all breast tumours. There is no treatment for them, and the role that cancer stem cells (CSCs) have in carcinogenesis is still unclear, so finding markers and therapeutic targets in CSC exosomes requires these cells to exist as a homogeneous cell population. The objective of this work was to determine differences in ultrastructural morphology, proliferative capacity, and mouse-xenotransplantation characteristics of the MDA-MB-231 and MDA-MB-436 TNBT cell lines with the CD44 high /CD24 low phenotype in order to study their exosomes. The results show that the CD44 high /CD24 low MBA-MB-231 cells had a population doubling time of 41.56 h, compared to 44.79 h in the MDA-MB-436 cell line. After magnetic immunoseparation, 18.75% and 14.56% of the stem cell population of the MDA-MB-231 and MDA-MB-436 cell lines, respectively, were of the ...
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Publicado 2015
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Aim: This retrospective study determined features associated with brain metastasis (BM) in women with breast cancer. Patients & methods: A total of 215 initially early breast cancer cases were included. We reviewed files and CT scan images of BM. Results: Median age was 47 years and most of our cases were stage III (58.6%), grade III (62.8%), ER negative (62.3%) and nonluminal (59.1%). Median survival after BM was 4 months. Nonluminal, extracranial disease, time to CNS shorter than 15 months, >three brain lesions and poor breast-graded prognostic assessment and recursive partitioning analysis scores were associated with shorter survival. Adding extracranial disease to breast-graded prognostic assessment score also predicted survival after BM. Radiation response was assessed in 57 patients and response tended to be associated with nonluminal phenotype but not with survival. Conclus...
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Publicado 2024
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Background: CD44 is a cell-surface transmembrane glycoprotein that participates in the regulation of many cellular processes, including cell division, adhesion, migration and stem-like characteristics. CD63 is involved in the exocytosis process. Objective: To evaluate the relationship between CD44 and CD63 expression and clinicopathological features, including tumor-infiltrating lymphocytes (TILs), phosphoinositide 3-kinase (PIK3CA) mutation and survival. Methodology: CD44 and CD63 were stained in samples from 101 breast cancer cases from Peruvian women. Results: Median age was 52 years, most were most were grade-3 (68%), estrogen receptor (ER)+ (64%) and stage II-III (92%). Median ki67 was 30%, median stromal TIL was 30% and PIK3CA mutation was found in 49%. Longer survival was associated with earlier stages (p = 0.016), lower ki67 (p = 0.023), ER+ (p = 0.034), luminal phenotype (p = 0....
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Publicado 2018
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Aim: To investigate the survival impact of clinicopathological factors, including pathological complete response (pCR) and tumor-infiltrating lymphocytes (sTIL) levels according to subtypes, in breast cancer (BC) patients who received neo-adjuvant chemotherapy (NAC). Methods: We evaluated 435 BC patients who presented and received NAC at the Instituto Nacional de Enfermedades Neoplasicas from 2003 to 2014. sTIL was analyzed as the proportion of tumor stroma occupied by lymphocytes, and was prospectively evaluated on hematoxylin and eosin-stained sections of the preNAC core biopsy. pCR was considered in the absence of infiltrating cancer cells in primary tumor and axillary lymph nodes. Analysis of statistical association between clinical pathological features, sTIL, pCR and survival were carried out using SPSSvs19. Results: Median age was 49 years (range 24-84 years) and the most frequent...
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Publicado 2019
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Background: For primary triple-negative breast cancer (TNBC) treated with neoadjuvant chemotherapy (NAC), higher pretreatment tumor-infiltrating lymphocytes (TILs) correlates with increased pathologic complete response (pCR) rates, and improved survival. We evaluated the added prognostic value of residual disease (RD) TILs to residual cancer burden (RCB) in predicting survival post-NAC. Patients and methods: We combined four TNBC NAC patient cohorts who did not achieve pCR. RD TILs were investigated for associations with recurrence-free survival (RFS), and overall survival (OS) using Cox models with stromal TILs as a continuous variable (per 10% increment). The likelihood ratio test was used to evaluate added prognostic value of RD TILs. Results: A total of 375 RD TNBC samples were evaluable for TILs and RCB. The median age was 50 years, with 62% receiving anthracycline/taxane chemothera...
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artículo
Publicado 2020
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Aim: Helicobacter pylori is usually detected based on hematoxylin-eosin (H-E) features, but, immunohistochemistry (IHC) and real-time PCR (RT-PCR) are more precise in chronic-gastritis. We evaluated the relevance of these tests in Peruvian gastric cancer samples. Materials & methods: We performed and evaluated H-E, IHC staining and RT-PCR in 288 gastric tumors. Slides were independently evaluated by three pathologists. Results: H. pylori was detected in 167/287 through H-E, 140/288 through IHC and 175/288 through RT-PCR, and positive-status were associated (p < 0.001). H. pylori detection by H-E had a good concordance with IHC (kappa index = 0.632) but poor with RT-PCR (kappa index = 0.317). Higher median gene-copies were found in high H. pylori density through H-E or IHC (p < 0.001). Conclusion: H-E evaluation is accurate in gastric cancer, and IHC and RT-PCR can complement its results....
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Publicado 2019
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PURPOSE Helicobacter pylori (HP) and Epstein Barr virus (EBV) infections induce chronic gastritis (CG) and are accepted carcinogenics of gastric cancer (GC). Our objective for this study was to determine the prevalence of these agents and clinicopathological features of GC and CG associated with the infection. PATIENTS AND METHODS A single-center cohort of 375 Peruvian patients with GC and 165 control subjects with CG were analyzed. Evaluation of HP and EBV genes was performed through quantitative polymerase chain reaction. RESULTS Prevalence of HP was 62.9% in the whole population and 60.8% in the GC subset. The cagA gene was detected in 79.9%; vacAs1 and vacAm1 alleles in 41.6% and 60.7%, respectively; and concurrent expression of vacAs1 and vacAm1 in 30.4% of infected patients in the whole series. The prevalence of EBV was 14.1% in the whole population and was higher in GC (P , .001)....