44 results match your criteria: "Center of Excellence in Translational Medicine-Scientific and Technological Bioresource CEMT-BIOREN[Affiliation]"

Study Question: Does oxidative stress (OS) activate autophagy in human sperm?

Summary Answer: Human spermatozoa subjected to OS activate an autophagic response.

What Is Known Already: Autophagy is a regulated pathway of lysosomal degradation which helps eukaryotic cells to maintain or restore homeostasis, being a cellular stress response mechanism. OS is a main cause of impaired sperm function and is linked to male infertility; however, whether OS activates autophagy in human spermatozoa is unknown.

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The human T cell lymphotropic virus type 1 (HTLV-1), unlike other RNA viruses such as HIV, has a stable genome and has infected humans since remote times. Although the HTLV-1 infection is endemic in South America, there is scarce information about HTLV-1 in Chile and its history of introduction. This study assessed the genomic content of HTLV-1 from Chile and its relationship with HTLV-1 lineages circulating worldwide by phylogenetic reconstruction and dating analyses.

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The Emerging Role of PIWI-Interacting RNAs (piRNAs) in Gastrointestinal Cancers: An Updated Perspective.

Cancers (Basel)

December 2021

Millennium Institute on Immunology and Immunotherapy, Department of Pathology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago 8380000, Chile.

Gastrointestinal (GI) cancers produce ~3.4 million related deaths worldwide, comprising 35% of all cancer-related deaths. The high mortality among GI cancers is due to late diagnosis, the presence of metastasis and drug resistance development.

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Chlamydia trachomatis is the most frequent bacterial sexually transmitted disease around the world. Estimated prevalence by WHO is 4,2% for women. Most cases are asymptomatic, but complications in fertility and during pregnancy are possible.

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Swine spermatozoa trigger aggregated neutrophil extracellular traps leading to adverse effects on sperm function.

J Reprod Immunol

August 2021

Center of Excellence in Translational Medicine - Scientific and Technological Bioresource Nucleus (CEMT - BIOREN), Faculty of Medicine, Universidad de La Frontera, Temuco, Chile; Department of Preclinical Sciences, Faculty of Medicine, Universidad de La Frontera, Temuco, Chile. Electronic address: r

In pigs, the number of PMN in uterus lumen increases within few hours after natural or artificial AI resulting in early PMN-derived innate immune reactions. Sperm-NETs formation was recently reported to occur in various mammalian species. Aim of this study was to investigate direct interactions of boar spermatozoa with swine PMN, the release of sperm-mediated NETs, and to assess NET-derived effects on sperm functionality.

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Seminal plasma, and not sperm, induces time and concentration-dependent neutrophil extracellular trap release in donkeys.

Equine Vet J

March 2022

Biotechnology of Animal and Human Reproduction (TechnoSperm), Institute of Food and Agricultural Technology, University of Girona, Girona, Spain.

Background: In several mammalian species, acute endometritis driven by the recruitment of polymorphonuclear cells (PMN) occurs in response to semen. These PMNs release DNA to form neutrophil extracellular traps (NETs) in cattle, horse and human, leading to sperm entrapment. While there is no evidence of this phenomenon occurring in donkeys, artificial insemination (AI) with frozen-thawed semen, which results in very poor pregnancy rates, leads to a large PMN recruitment to the uterus.

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Human spermatozoa activate neutrophil extracellular traps (NETs) in vitro. NETosis is an efficient mechanism through which polymorphonuclear neutrophils (PMN) capture sperm in vitro. The objective of this study was to establish the role of store-operated Ca+2 entry (SOCE) in human sperm-triggered NETs and its impact on sperm integrity and oocyte binding capacity.

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Human T-cell lymphotropic virus type 1 (HTLV-1) is a globally-spread virus. It is estimated that there are about 5–10 million infected people in the world. HTLV is endemic in Chile, with higher seroprevalence among indigenous people.

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Purpose: To study the effector mechanism against pathogens of polymorphonuclear neutrophils (PMN) and macrophages, called ETosis, involving the release of extracellular traps (ETs) in patients with acute epididymitis. To assess the different ET phenotypes present in semen samples and to identify correlations between ETosis and clinical parameters.

Materials And Methods: Samples from patients diagnosed with acute epididymitis were examined and compared with samples from uninfected controls.

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Molecular alterations that contribute to long-term (LT) and short-term (ST) survival in ovarian high-grade serous carcinoma (HGSC) may be used as precision medicine biomarkers. DNA promoter methylation is an early event in tumorigenesis, which can be detected in blood and urine, making it a feasible companion biomarker to somatic mutations for early detection and targeted treatment workflows. We compared the methylation profile in 12 HGSC tissue samples to 30 fallopian tube epithelium samples, using the Infinium Human Methylation 450K Array.

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Sperm cryopreservation is widely used in assisted reproduction and male infertility therapy; however, it induces oxidative stress affecting sperm quality. This work evaluated the effect of the antioxidant MnTBAP during vitrification steps in human spermatozoa. First, the effect of MnTBAP on viability and ROS production was evaluated.

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Male infertility is an increasing health problem, and oxidative/nitrosative stress plays an important role in the etiology of this condition. Nitrosative stress due to excessive levels of reactive nitrogen species (RNS) is associated with impaired male fertility. Flow cytometry may be a useful tool for semen evaluation, but the availability of multiparameter assays for analysis of sperm quality is limited.

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Fucoidans are sulphated polysaccharides that can be obtained from brown seaweed and marine invertebrates. They have anti-cancer properties, through their targeting of several signaling pathways and molecular mechanisms within malignant cells. This review describes the chemical structure diversity of fucoidans and their similarity with other molecules such as glycosaminoglycan, which enable them to participation in diverse biological processes.

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Oxidative stress contributes importantly to the aetiology of male infertility, impairing sperm function. The protective effect of antioxidants on seminal parameters has been established, and the antioxidant penicillamine has shown beneficial effects; however, its protective effect on human spermatozoa exposed to oxidative stress has not been reported. The objective of this work was to evaluate the effect of penicillamine on human spermatozoa exposed in vitro to oxidative stress.

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Assessment of Gastritis and Gastric Cancer Risk in the Chilean Population Using the OLGA System.

Pathol Oncol Res

July 2019

Department of Pathological Anatomy, School of Medicine, Universidad de La Frontera, Avenida Alemania 0458, Postal Code, 4810296, Temuco, Chile.

Gastric cancer (GC) is the first cancer-related cause of death in Chile; however, no plan for GC early detection has been implemented in this country. The OLGA system characterizes gastritis from stages 0 to IV according to the risk of developing GC based on H. pylori infection, atrophy, metaplasia and GC.

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Microbiome studies show altered microbiota in head and neck squamous cell carcinoma (HNSCC), both in terms of taxonomic composition and metabolic capacity. These studies utilized a traditional bioinformatics methodology, which allows for accurate taxonomic assignment down to the genus level, but cannot accurately resolve species level membership. We applied Resphera Insight, a high-resolution methodology for 16S rRNA taxonomic assignment that is able to provide species-level context in its assignments of 16S rRNA next generation sequencing (NGS) data.

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Sperm cryopreservation is common in assisted reproduction laboratories, providing a therapeutic option for several clinical conditions. This process has been optimized; however, the effect of post-thaw incubation temperature has been poorly studied. This work analyzed the effect of incubation temperature after devitrification on human sperm quality.

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Clinically useful molecular tools to triage gastric cancer patients are not currently available. We aimed to develop a molecular tool to predict gastric cancer risk in endoscopy-driven biopsies obtained from high-risk gastric cancer clinics in low resource settings.We discovered and validated a DNA methylation biomarker panel in endoscopic samples obtained from 362 patients seen between 2004 and 2009 in three high-risk gastric cancer clinics in Lima, Perú, and validated it in 306 samples from the Cancer Genome Atlas project ("TCGA").

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The ERK/MAPK pathway is overexpressed and activated in gallbladder cancer.

Pathol Res Pract

May 2017

Department of Pathology, UC Centre for Investigational Oncology (CITO), Advanced Centre for Chronic Diseases (ACCDiS), Millennium Institute on Immunology and Immunotherapy, Pontificia Universidad Católica de Chile, Santiago, Chile. Electronic address:

Gallbladder cancer (GBC) is a highly fatal disease with poor prognosis and few therapeutic alternatives. Molecular profiling has revealed that the deregulation in the ERK/MAPK signaling pathway plays a crucial role in many disease and malignancies, including GBC. The aim of this study was to measure the expression of ERK1/2 and p-ERK1/2 in a population with high GBC-related mortality, such as the Chilean population, and characterize the protein expression of this ERK/MAPK pathway in seven GBC cell lines.

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