Post-mortem assessment of vimentin expression as a biomarker for renal tubular regeneration following acute kidney injury

Juan Carlos Alvarez Moreno,Hisham F. Bahmad,Christopher A. Febres-Aldana,Andrés Pirela,Andres Azuero,Ali Salami,Robert Poppiti 대한병리학회 2021 Journal of Pathology and Translational Medicine Vol.55 No.6

Background: Acute kidney injury (AKI) is a common cause of morbidity and mortality. It mainly targets the renal tubular epithelium with pathological changes, referred to as acute tubular injury. The latter is followed by a regenerative response that is difficult to visualize on routine hematoxylin and eosin (H&E) stains. In this study, we examined the regenerative capacity of renal tubules by correlating vimentin (VIM) immunohistochemical (IHC) expression and pathological findings of AKI and renal tubular regeneration (RTR) on H&E.Methods: We reviewed 23 autopsies performed in the clinical setting of AKI and RTR. VIM expression was scored in the renal cortical tubular epithelium using a statistical cutoff ≥ 3% for high expression and < 3% for low expression.Results: Of the 23 kidney tissues examined, seven (30.4%) had low VIM expression, and 16 (69.6%) had high VIM expression. Kidney tissues with evidence of AKI and RTR had significantly higher VIM expression. Renal peritubular microenvironment features showing regenerative changes on H&E were associated with high VIM expression. In the univariate model, kidney tissues with RTR were 18-fold more likely to have high VIM expression.Conclusions: In conclusion, our findings suggest that VIM could serve as an IHC marker for RTR following AKI. However, correlation with H&E findings remains critical to excluding chronic tubular damage. Collectively, our preliminary results pave the way for future studies including a larger sample size to validate the use of VIM as a reliable biomarker for RTR.

Prognostic role of genetic biomarkers in clinical progression of prostate cancer

Maria Jesus Alvarez-Cubero,Luis Javier Martinez-Gonzalez,Maria Saiz,Pedro Carmona-Saez,Juan Carlos Alvarez,Manrique Pascual-Geler,Jose Antonio Lorente,Jose Manuel Cozar 생화학분자생물학회 2015 Experimental and molecular medicine Vol.47 No.-

The aim of this study was to analyze the use of 12 single-nucleotide polymorphisms in genes ELAC2, RNASEL and MSR1 as biomarkers for prostate cancer (PCa) detection and progression, as well as perform a genetic classification of high-risk patients. A cohort of 451 men (235 patients and 216 controls) was studied. We calculated means of regression analysis using clinical values (stage, prostate-specific antigen, Gleason score and progression) in patients and controls at the basal stage and after a follow-up of 72 months. Significantly different allele frequencies between patients and controls were observed for rs1904577 and rs918 (MSR1 gene) and for rs17552022 and rs5030739 (ELAC2). We found evidence of increased risk for PCa in rs486907 and rs2127565 in variants AA and CC, respectively. In addition, rs627928 (TT–GT), rs486907 (AG) and rs3747531 (CG–CC) were associated with low tumor aggressiveness. Some had a weak linkage, such as rs1904577 and rs2127565, rs4792311 and rs17552022, and rs1904577 and rs918. Our study provides the proof-of-principle that some of the genetic variants (such as rs486907, rs627928 and rs2127565) in genes RNASEL, MSR1 and ELAC2 can be used as predictors of aggressiveness and progression of PCa. In the future, clinical use of these biomarkers, in combination with current ones, could potentially reduce the rate of unnecessary biopsies and specific treatments.

Experimental and numerical analysis of new bricks made up of polymer modified-cement using expanded vermiculite

Fuat Köksal,Juan J. del Coz Diaz,Osman Gencel,Felipe P. Alvarez Rabanal 사단법인 한국계산역학회 2013 Computers and Concrete, An International Journal Vol.12 No.3

In this paper, the properties of the cement mortar modified with styrene acrylic ester copolymer were investigated. Expanded vermiculite as lightweight aggregate was used for making the polymer modified mortar test specimens. To study the effect of polymer–cement ratio and vermiculite-cement ratio on various properties, specimens were prepared by varying the polymer–cement and vermiculite-cement ratios. Tests of physical properties such as density, water absorption, thermal conductivity, three-point flexure and compressive tests were made on the specimens. Furthermore, a coupled thermal-structural finite element model of an entire corner wall was modelled in order to study the best material configuration. The wall is composed by a total of 132 bricks of 120 × 242 × 54 size, joined by means of a contact-bonded model. The use of advanced numerical methods allows us to obtain the optimum material properties. Finally, comparisons of polymer–cement and vermiculite-cement ratios on physical properties are given and the most important conclusions are exposed.

Development of a Stand Density Management Diagram for Teak Forests in Southern India

Tewari, Vindhya Prasad,Alvarez-Gonz, Juan Gabriel Institute of Forest Science 2014 Journal of Forest Science Vol.30 No.3

Stand Density Diagrams (SDD) are average stand-level models which graphically illustrate the relationship between yield, density and mortality throughout the various stages of forest development. These are useful tools for designing, displaying and evaluating alternative density regimes in even-aged forest ecosystems to achieve a desired future condition. This contribution presents an example of a SDD that has been constructed for teak forests of Karnataka in southern India. The relationship between stand density, dominant height, quadratic mean diameter, relative spacing and stand volume is represented in one graph. The relative spacing index was used to characterize the population density. Two equations were fitted simultaneously to the data collected from 27 sample plots measured annually for three years: one relates quadratic mean diameter with stand density and dominant height while the other relates total stand volume with quadratic mean diameter, stand density and dominant height.

Establishment of a loop-mediated isothermal amplification (LAMP) assay for the detection of phytoplasma-associated cassava witches’ broom disease

Nam Tuan Vu,Juan Manuel Pardo,Elizabeth Alvarez,Ham Huy Le,Kris Wyckhuys,Kim-Lien Nguyen,Dung Tien Le 한국응용생명화학회 2016 Applied Biological Chemistry (Appl Biol Chem) Vol.59 No.2

Cassava (Manihot esculenta Crantz) is one of the most important food crops in the tropics; however, bacterial phytopathogens pose a serious threat to its farming. Cassava Witches’ Broom Disease (CWB) is caused by the infection of phytoplasma and is manifested as reduction in tuber yield and starch content at harvest of 10 and 30 %, respectively. Although polymerase-chain reaction provides the gold standard in diagnostics, this method requires significant investments in infrastructure and training. Here, we developed a loop-mediated isothermal amplification (LAMP) assay that allows specific detection of phytoplasma from field-collected samples. Three primer sets were designed, of which two detected phytoplasma DNA sequence encoding 16S rRNA (16S rDNA), the other detected cassava actin. Following a 1 h LAMP reaction at 63 °C, a positive reaction can be visualized by agarose gel electrophoresis, hydroxynaphthol blue color change, or the presence of a precipitate. In a pilot field study, the assay was able to rapidly distinguish between healthy and CWB-infected cassava. With further development, a LAMP for routine on-site screening of cassava crops can be envisioned.

Development of Robotics Projects to Introduce the Applied Research Culture in the Engineering Undergraduate Programs

Fernando Ramos-Quintana,Victor Hugo Zarate-Silva,Juan Alvarez 한국과학기술원 인간친화 복지 로봇 시스템 연구센터 2005 International Journal of Assistive Robotics and Me Vol.6 No.2

  This paper describes an initiative to introduce mechanisms oriented to create motivational attitudes for developing applied research in the undergraduate level, instead of focusing such efforts only in the graduate level. An important part of these efforts are carried out under the framework of several robotics projects, in particular walking robots and simulated and real soccer robots. Along with this, a curriculum to assure long term technical goals has been specially designed. Thus, the projects should provide the necessary ingredients to encourage the students to develop autonomous behaviors and maintain persistent motivational attitudes by interacting with attractive technical challenges.<BR>  We have adopted formal learning models that help to develop cognitive skills for solving problems, such as Problem Based Learning (PBL). In a first step, during four semesters of the years 2002 and 2003, the PBL model, along with projects in soccer robots, has been applied in the undergraduate and graduate level. Since 2004 these efforts have been focused on the undergraduate level. And, we have already witnessed some key results; the students have acquired interesting motivational attitudes in applied research projects in robotics; they have developed cognitive skills for solving problems; and they have got successful participations in international robotics competitions.

Male Oxidative Stress Infertility (MOSI): Proposed Terminology and Clinical Practice Guidelines for Management of Idiopathic Male Infertility

Ashok Agarwal,Neel Parekh,Manesh Kumar Panner Selvam,Ralf Henkel,Rupin Shah,Sheryl T. Homa,Ranjith Ramasamy,Edmund Ko,Kelton Tremellen,Sandro Esteves,Ahmad Majzoub,Juan G. Alvarez,David K. Gardner,Cha 대한남성과학회 2019 The World Journal of Men's Health Vol.37 No.3

Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diagnose and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role in the etiology of male infertility, with 30% to 80% of infertile men having elevated seminal reactive oxygen species levels. OS can negatively affect fertility via a number of pathways, including interference with capacitation and possible damage to sperm membrane and DNA, which may impair the sperm’s potential to fertilize an egg and develop into a healthy embryo. Adequate evaluation of male reproductive potential should therefore include an assessment of sperm OS. We propose the term Male Oxidative Stress Infertility, or MOSI, as a novel descriptor for infertile men with abnormal semen characteristics and OS, including many patients who were previously classified as having idiopathic male infertility. Oxidation-reduction potential (ORP) can be a useful clinical biomarker for the classification of MOSI, as it takes into account the levels of both oxidants and reductants (antioxidants). Current treatment protocols for OS, including the use of antioxidants, are not evidence-based and have the potential for complications and increased healthcare-related expenditures. Utilizing an easy, reproducible, and cost-effective test to measure ORP may provide a more targeted, reliable approach for administering antioxidant therapy while minimizing the risk of antioxidant overdose. With the increasing awareness and understanding of MOSI as a distinct male infertility diagnosis, future research endeavors can facilitate the development of evidence-based treatments that target its underlying cause.