Publications by authors named "Luis A Jimenez"

Article Synopsis
  • Genomic analysis of an invasive marine snail from Elkhorn Slough in California led to the assembly of its complete mitochondrial genome, which measures 16,095 base pairs and includes various genes like rRNA, protein-coding, and tRNA.
  • The organization and gene content of this mitogenome match those found in the Turritellidae and Pachychilidae families, indicating a close evolutionary relationship.
  • Phylogenetic analysis confirms it belongs to a clade with these families within the Cerithioidea superfamily, and similar genetic sequences were found in invasive populations from California and British Columbia, as well as native populations from Japan, highlighting the utility of mitogenome sequencing for classification and evolutionary studies.
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Accurate quantitation of low dose, multi-active dissolution samples poses unique challenges in the pharmaceutical industry, often resulting in separate HPLC methods for each active or the use of multiple detectors for increased sensitivity. In this study, we report a fast, isocratic HPLC method utilizing only UV detection for dissolution testing of low dose desogestrel and ethinylestradiol tablets. Rapid separation is completed in 5 min using isocratic elution at a flow rate of 0.

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MicroRNAs (miRNAs) are small RNAs, that bind to mRNA targets and regulate their translation. Functional study of miRNAs and exploration of their utility as disease markers require miRNA extraction from biological samples, which contain large amounts of interfering compounds for downstream RNA identification and quantification. The most common extraction methods employ either silica columns or TRIzol reagent, but these approaches afford low recovery for small RNAs, possibly due to their short strand lengths.

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Article Synopsis
  • Non-coding RNAs (ncRNAs) play a crucial role in gene regulation and are linked to disease development, making them valuable potential biomarkers found in body fluids.
  • Significant advancements are needed in the extraction, quantification, and analysis of circulating ncRNAs for effective clinical diagnosis and prognosis, particularly in cancer.
  • The review emphasizes recent technological progress in ncRNA research, focusing on methods to purify, quantify, and use microfluidic platforms for non-invasive point-of-care diagnostics.
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DNA methyltransferases (DNMTs) are enzymes responsible for establishing and maintaining DNA methylation in cells. DNMT inhibition is actively pursued in cancer treatment, dominantly through the formation of irreversible covalent complexes between small molecular compounds and DNMTs that suffers from low efficacy and high cytotoxicity, as well as no selectivity towards different DNMTs. Herein, we discover aptamers against the maintenance DNA methyltransferase, DNMT1, by coupling Asymmetrical Flow Field-Flow Fractionation (AF4) with Systematic Evolution of Ligands by EXponential enrichment (SELEX).

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Study Objective: To determine the surgical time, suture time, presence of postoperative dyspareunia, and complications that occur after closing the vaginal cuff with a barbed suture compared with conventional suture.

Design: A randomized, controlled clinical trial (Canadian Task Force classification I).

Setting: Private gynecologic clinic in Medellin, Colombia.

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MicroRNAs (miRNAs) are small RNAs that bind to mRNA targets and regulate their translation. A functional study of miRNAs and exploration of their utility as disease markers require miRNA extraction from biological samples, which contain large amounts of interfering compounds for downstream RNA identification and quantification. The most common extraction methods employ silica columns or the TRIzol reagent but give out low recovery for small RNAs probably due to their short strand lengths.

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The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in , but it is substantially larger (>18.

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MicroRNAs (miRNAs) are stably present in circulatory systems. They are bound to various carriers like proteins, lipoprotein particles, and exosomes. Investigating the process of miRNA distribution among these carriers will help improve our understanding of their functions in the extracellular environment and their potential relationship with diseases.

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The Muller F element (4.2 Mb, ~80 protein-coding genes) is an unusual autosome of Drosophila melanogaster; it is mostly heterochromatic with a low recombination rate. To investigate how these properties impact the evolution of repeats and genes, we manually improved the sequence and annotated the genes on the D.

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Circulating microRNAs (miRNAs) are potential biomarkers useful in cancer diagnosis. They have been found to be bound to various carriers like proteins, lipoprotein particles, and exosomes. It is likely that only miRNAs in particular carriers, but not the overall quantity, are directly related to cancer development.

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Tools capable of measuring binding affinities as well as amenable to downstream sequencing analysis are needed for study of DNA-protein interaction, particularly in discovery of new DNA sequences with affinity to diverse targets. Asymmetrical flow field-flow fractionation (AF4) is an open-channel separation technique that eliminates interference from column packing to the non-covalently bound complex and could potentially be applied for study of macromolecular interaction. The recovery and elution behaviors of the poly(dA)n strand and aptamers in AF4 were investigated.

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Rationale: Chronic obstructive pulmonary disease (COPD) is believed to result from an abnormal inflammatory response in the lungs to noxious particles and gases usually found in cigarette smoke.

Objectives: In this study, the molecular mechanisms for the enhanced proinflammatory cytokine gene transcription in COPD were investigated.

Methods: Lung tissue was examined from 56 subjects undergoing resection for peripheral lung tumors as follows: current smokers with (n = 14) and without COPD (n = 17), ex-smokers with COPD (n = 13), and nonsmokers (n = 12).

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This review considers the molecular toxicology of combustion-derived nanoparticles (CDNP) following inhalation exposure. CDNP originate from a number of sources and in this review we consider diesel soot, welding fume, carbon black and coal fly ash. A substantial literature demonstrates that these pose a hazard to the lungs through their potential to cause oxidative stress, inflammation and cancer; they also have the potential to redistribute to other organs following pulmonary deposition.

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Changes in the ratio of intracellular reduced and disulfide forms of glutathione (GSH/GSSG) can affect signaling pathways that participate in various physiological responses from cell proliferation to gene expression and apoptosis. It is also now known that many proteins have a highly conserved cysteine (sulfhydryl) sequence in their active/regulatory sites, which are primary targets of oxidative modifications and thus important components of redox signaling. However, the mechanism by which oxidants and GSH/protein-cysteine-thiols actually participate in redox signaling still remains to be elucidated.

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Oxidants and tumor necrosis factor-alpha (TNF-alpha) activate transcription factors such as nuclear factor-kappaB (NF-kappaB), which is involved in the transcription of proinflammatory mediators, including interleukin-8 (IL-8). Curcumin (diferuloylmethane) is a naturally occurring flavonoid present in the spice turmeric, which has a long traditional use as a chemotherapeutic agent for many diseases. We hypothesize that curcumin may possess both antioxidant and antiinflammatory properties by increasing the glutathione levels and inhibiting oxidant- and cytokine-induced NF-kappaB activation and IL-8 release from cultured alveolar epithelial cells (A549).

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This review focuses on the potential role that oxidative stress plays in the adverse effects of PM(10). The central hypothesis is that the ability of PM(10) to cause oxidative stress underlies the association between increased exposure to PM(10) and both exacerbations of lung disease and lung cancer. Pulmonary inflammation may also underlie the cardiovascular effects seen following increased PM(10), although the mechanisms of the cardiovascular effects of PM(10) are not well understood.

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Oxidants and inflammatory mediators such as tumour necrosis factor-alpha (TNF-alpha) activate transcription factors such as NF-kappa B. Interleukin-8 (IL-8) is a ubiquitous inflammatory chemokine that mediates a multitude of inflammatory events in the lung. Ergothioneine is a naturally occurring thiol compound, which possesses antioxidant property.

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Oxidants and inflammatory mediators such as tumour necrosis factor-alpha (TNF-alpha) activate nuclear factor kappa B (NF-kappaB) and activator protein-1 (AP-1) transcription factors, and enhance the expression of both pro-inflammatory and protective antioxidant genes. Remodelling of chromatin within the nucleus, controlled by the degree of acetylation/deacetylation of histone residues on the histone core around which DNA is coiled, is important in allowing access for transcription factor DNA binding and hence gene transcription. Unwinding of DNA is important in allowing access for transcription factor DNA binding and hence gene transcription.

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