Publications by authors named "Contreras L"

Article Synopsis
  • General RNA chaperones are proteins that help RNA molecules fold correctly and avoid misfolding, which is crucial for bacteria, especially with large and complex RNA structures.
  • Researchers adapted a technique to screen for factors affecting RNA folding and identified eight proteins that influence the folding of a specific RNA ribozyme when deleted.
  • Among these, YagL and PepA were found to bind RNA and assist in the folding process, with YagL being especially effective in promoting correct refolding of misfolded RNA, thanks to a specific protein domain responsible for its activity.
View Article and Find Full Text PDF

Bulk increases in nucleobase oxidation, most commonly manifesting as the guanine (G) nucleobase modification 8-oxo-7,8-dihydroguanine (8-oxoG), have been linked to several disease pathologies. Elucidating the effects of RNA oxidation on cellular homoeostasis is limited by a lack of effective tools for detecting specific regions modified with 8-oxoG. Building on a previously published method for studying 8-oxoG in DNA, we developed ChLoRox-Seq, which works by covalently functionalizing 8-oxoG sites in RNA with biotin.

View Article and Find Full Text PDF
Article Synopsis
  • RNA oxidation, particularly the formation of 8-oxo-7,8-dihydroguanosine (8-oxo-rG), serves as a key indicator of oxidative stress in cells.
  • Polynucleotide phosphorylase (PNPase) helps protect cells from oxidative stress by recognizing and degrading RNA containing 8-oxo-rG, but how 8-oxo-rG affects this process was previously unclear.
  • This study finds that 8-oxo-rG causes PNPase to stall during RNA degradation, particularly due to a crucial residue (Arg399), influencing bacterial survival under stress conditions.
View Article and Find Full Text PDF

As synthetic biology expands, creating "drag-and-drop" regulatory tools that can achieve diverse regulatory outcomes are paramount. Herein, we develop a approach for engineering complex post-transcriptional control by rewiring the Carbon Storage Regulatory (Csr) Network of Escherichia coli. We co-opt native interactions of the Csr Network to establish post-transcriptional logic gates and achieve complex bacterial regulation.

View Article and Find Full Text PDF

Histidine ammonia-lyase (HAL) plays a pivotal role in the non-oxidative deamination of L-histidine to produce -urocanic, a crucial process in amino acid metabolism. This study examines the cloning, purification, and biochemical characterization of a novel HAL from (HAL) and eight active site mutants to assess their effects on substrate binding, catalysis, thermostability, and secondary structure. The HAL enzyme was successfully overexpressed and purified to homogeneity.

View Article and Find Full Text PDF

Introduction: Numerous studies have found that exposure to violence at home is a risk factor for child-to-parent violence. However, most of the available studies do not delimit a time frame for exposure to violence. This aspect is fundamental to differentiating lagged effects (compensation) from simultaneous effects (reciprocal).

View Article and Find Full Text PDF

Antiviral responses induced by double-stranded RNA (dsRNA) include RNA interference (RNAi) and pattern-triggered immunity (PTI), but their relative contributions to antiviral defence are not well understood. We aimed at testing the impact of exogenous applied dsRNA on both layers of defence against potato virus X expressing GFP (PVX-GFP) in Nicotiana benthamiana. Co-inoculation of PVX-GFP with either sequence-specific (RNAi) or nonspecific dsRNA (PTI) showed that nonspecific dsRNA reduced virus accumulation in both inoculated and systemic leaves.

View Article and Find Full Text PDF

Unlabelled: The trait of ionizing radiation (IR) tolerance is variable between bacterium, with species succumbing to acute doses as low as 60 Gy and extremophiles able to survive doses exceeding 10,000 Gy. While survival screens have identified multiple highly radioresistant bacteria, such systemic searches have not been conducted for IR-sensitive bacteria. The taxonomy-level diversity of IR sensitivity is poorly understood, as are genetic elements that influence IR sensitivity.

View Article and Find Full Text PDF

By incorporating the culturally relevant leadership learning model (CRLL) into the leadership learning framework (LLF), this article provides leadership educators with an inclusive approach to leadership learning. The authors illustrate how educators can integrate the five dimensions of campus climate into leadership knowledge, observation, development, training, engagement, and metacognition. We describe practical ways to address leadership identity, efficacy, and capacity development for all college students, especially those belonging to traditionally underserved identities.

View Article and Find Full Text PDF

Recent research has indicated the presence of heterochromatin-like regions of extended protein occupancy and transcriptional silencing of bacterial genomes. We utilized an integrative approach to track chromatin structure and transcription in K-12 across a wide range of nutrient conditions. In the process, we identified multiple loci which act similarly to facultative heterochromatin in eukaryotes, normally silenced but permitting expression of genes under specific conditions.

View Article and Find Full Text PDF

The issue of obstetric violence is internationally acknowledged as a serious violation of human rights. First identified by the Committee of Experts of the Inter-American Belém do Pará Convention in 2012, it is recognized as a form of gender-based violence that infringes upon women's rights during childbirth. Nations such as Argentina, Mexico, Venezuela, and certain regions in Spain have implemented laws against it, highlighting its severity and the need for protective legislation.

View Article and Find Full Text PDF

Imaging techniques play a crucial role in characterizing environmental plastics. However, most reported findings rely on two-dimensional projections of particles resting on flat surfaces. This limitation makes it challenging to accurately determine mass concentration, which is essential for deriving toxicologically relevant exposure data.

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on an extremophile that maintains a highly organized nucleoid, which may help it tolerate ionizing radiation (IR).
  • A new high-throughput method combining confocal microscopy and computational modeling is introduced to quantitatively analyze nucleoid and cell geometry under IR stress.
  • Results show that IR exposure leads to nucleoid compaction, alters cell morphology, and suggests potential roles for nucleoid-associated proteins in regulating these changes.
View Article and Find Full Text PDF

Empirical evidence supports the simultaneous relationship between parental warmth and child-to-parent violence (CPV). However, no studies analyze the lagged effects of perceived parental warmth and the potential impact of cognitive mechanisms legitimizing immoral behavior on this relationship. This study aimed to examine the mediating role of moral disengagement strategies (reconstruction of immoral behavior, obscuring personal responsibility, misrepresenting injurious consequences, and blaming the victim) in the relationship between the perceived paternal and maternal warmth dimensions (warmth-communication and criticism-rejection) during childhood and CPV towards the father and mother.

View Article and Find Full Text PDF

Global rewiring of bacterial gene expressions in response to environmental cues is mediated by regulatory proteins such as the CsrA global regulator from Several direct mRNA and sRNA targets of this protein have been identified; however, high-throughput studies suggest an expanded RNA targetome for this protein. In this work, we demonstrate that CsrA can extend its network by directly binding and regulating the and transcripts, encoding for regulatory proteins. CsrA represses EvgA and AcnA expression and disrupting the CsrA binding sites of and , results in broader gene expression changes to stress response networks.

View Article and Find Full Text PDF

Background And Objectives: There has been a prevailing but erroneous belief in the medical community that there is a biological vulnerability in the American Indian/Alaskan Native (AI/AN) community to substance use disorders (SUDs), with alcohol use disorder (AUD) being the most prevalent. This scoping review aimed to examine what possible psychosocial issues could lead to the development of the perpetuation of SUDs in the AI/AN population.

Methods: The protocol for this scoping review followed Arksey and O'Malley's methodological framework.

View Article and Find Full Text PDF

Zika virus (ZIKV) can cause neurological issues in infants. To provide protection, neutralizing antibodies should be transferred from the mother to the infant. We conducted a study at the Hospital General de Pochutla, Oaxaca, Mexico.

View Article and Find Full Text PDF

Junior tennis players travel a lot to play tennis tournaments; this causes them to spend a lot of time away from their homes and disrupts their training, which could reduce their performance and increase the risk of injury. The purpose of this study was to analyze the changes in physical performance and body composition after a six-week international tour in young Chilean female tennis players. Thirty young female tennis players (15.

View Article and Find Full Text PDF

Superabsorbent polymer (SAP) granules, typically used in personal care devices such as diapers, incontinence devices, hygiene pads, and wound dressings, and granular particles of zeolite and bentonite were each subjected to modification by exposure to solutions of 1-chloro-2,2,5,5-tetramethyl-4-imidazolidinone (MC) in ethanol at room temperature. The air-dried granules showed newly acquired properties attributable to the presence of active chlorine (Cl). The treated particles effectively oxidized the malodorant 3-mercapto-3-methylbutanol (3M3MB).

View Article and Find Full Text PDF

Recent genomic studies in adult and pediatric acute myeloid leukemia (AML) demonstrated recurrent in-frame tandem duplications (TD) in exon 13 of upstream binding transcription factor (UBTF). These alterations, which account for approximately 4.3% of AML in childhood and about 3% in adult AML aged <60 years of age, are subtype-defining and associated with poor outcomes.

View Article and Find Full Text PDF

Cancer most frequently develops in self-renewal tissues that are the target of genetic alterations due to mutagens or intrinsic DNA replication errors. Histone γH2AX has a critical role in the cellular DNA repair pathway cascade and contributes to genomic stability. However, the role of γH2AX in the ontology of cancer is unclear.

View Article and Find Full Text PDF
Article Synopsis
  • Mesalamine is a medication commonly used to treat inflammatory bowel disease, but there is a rare risk of hepatotoxicity reported in 0-4% of cases.
  • A 79-year-old woman treated with mesalamine for left-sided ulcerative colitis developed symptoms such as headache, fatigue, and low fever after three months, with abnormal liver test results indicating liver issues.
  • After stopping mesalamine, further tests revealed bile duct dilation and a liver biopsy showed chronic cholangitis with granulomas, but no signs of liver failure.
View Article and Find Full Text PDF