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1.
Int J Mol Sci ; 24(2)2023 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-36674758

RESUMEN

Recent advances have suggested that non-coding miRNAs (such as miR-21, miR-27, miR-145, miR-155, miR-365, miR-375 and miR-494) may be involved in multiple aspects of oral cancer chemotherapeutic responsiveness. This study evaluated whether these specific miRNAs are correlated with oral cancer responsiveness to chemotherapies, including Paclitaxel, Cisplatin and Fluorouracil (5FU). Commercially available and well-characterized oral squamous cell carcinoma cell lines (SCC4, SCC9, SCC15, SCC25 and CAL27) revealed differing resistance and chemosensitivity to these agents-with SCC9 and SCC25 demonstrating the most resistance to all chemotherapeutic agents. SCC9 and SCC25 were also the only cell lines that expressed miR-375, and were the only cell lines that did not express miR-27. In addition, the expression of miR-375 was associated with the upregulation of Rearranged L-myc fusion (RLF) and the downregulation of Centriolar protein B (POC1), whereas lack of miR-27 expression was associated with Nucleophosmin 1 (NPM1) expression. These data have revealed important regulatory pathways and mechanisms associated with oral cancer proliferation and resistance that must be explored in future studies of potential therapeutic interventions.


Asunto(s)
Carcinoma de Células Escamosas , MicroARNs , Neoplasias de la Boca , Humanos , MicroARNs/metabolismo , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/genética , Neoplasias de la Boca/metabolismo , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Cisplatino/uso terapéutico , Resistencia a Antineoplásicos/genética , Proliferación Celular , Regulación Neoplásica de la Expresión Génica
2.
Int J Mol Sci ; 24(4)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36835366

RESUMEN

Chronic pancreatitis is characterized by chronic inflammation and fibrosis, processes heightened by activated pancreatic stellate cells (PSCs). Recent publications have demonstrated that miR-15a, which targets YAP1 and BCL-2, is significantly downregulated in patients with chronic pancreatitis compared to healthy controls. We have utilized a miRNA modification strategy to enhance the therapeutic efficacy of miR-15a by replacing uracil with 5-fluorouracil (5-FU). We demonstrated increased levels of YAP1 and BCL-2 (both targets of miR-15a) in pancreatic tissues obtained from Ptf1aCreERTM and Ptf1aCreERTM;LSL-KrasG12D mice after chronic pancreatitis induction as compared to controls. In vitro studies showed that delivery of 5-FU-miR-15a significantly decreased viability, proliferation, and migration of PSCs over six days compared to 5-FU, TGFß1, control miR, and miR-15a. In addition, treatment of PSCs with 5-FU-miR-15a in the context of TGFß1 treatment exerted a more substantial effect than TGFß1 alone or when combined with other miRs. Conditioned medium obtained from PSC cells treated with 5-FU-miR-15a significantly inhibits the invasion of pancreatic cancer cells compared to controls. Importantly, we demonstrated that treatment with 5-FU-miR-15a reduced the levels of YAP1 and BCL-2 observed in PSCs. Our results strongly suggest that ectopic delivery of miR mimetics is a promising therapeutic approach for pancreatic fibrosis and that 5-FU-miR-15a shows specific promise.


Asunto(s)
Fluorouracilo , MicroARNs , Células Estrelladas Pancreáticas , Pancreatitis Crónica , Animales , Ratones , Proliferación Celular/genética , Fibrosis , Fluorouracilo/farmacología , MicroARNs/genética , MicroARNs/metabolismo , Células Estrelladas Pancreáticas/efectos de los fármacos , Células Estrelladas Pancreáticas/patología , Pancreatitis Crónica/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Señalizadoras YAP/metabolismo
3.
Mol Syst Biol ; 16(7): e9427, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32657546

RESUMEN

Programmable gene activation enables fine-tuned regulation of endogenous and synthetic gene circuits to control cellular behavior. While CRISPR-Cas-mediated gene activation has been extensively developed for eukaryotic systems, similar strategies have been difficult to implement in bacteria. Here, we present a generalizable platform for screening and selection of functional bacterial CRISPR-Cas transcription activators. Using this platform, we identified a novel CRISPR activator, dCas9-AsiA, that could activate gene expression by more than 200-fold across genomic and plasmid targets with diverse promoters after directed evolution. The evolved dCas9-AsiA can simultaneously mediate activation and repression of bacterial regulons in E. coli. We further identified hundreds of promoters with varying basal expression that could be induced by dCas9-AsiA, which provides a rich resource of genetic parts for inducible gene activation. Finally, we show that dCas9-AsiA can be ported to other bacteria of clinical and bioindustrial relevance, thus enabling bacterial CRISPRa in more application areas. This work expands the toolbox for programmable gene regulation in bacteria and provides a useful resource for future engineering of other bacterial CRISPR-based gene regulators.


Asunto(s)
Sistemas CRISPR-Cas/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Ingeniería de Proteínas/métodos , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de los fármacos , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/metabolismo , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/efectos de los fármacos , Evolución Molecular Dirigida , Escherichia coli/genética , Regulación Bacteriana de la Expresión Génica/genética , Biblioteca de Genes , Genes Reporteros/efectos de los fármacos , Genes Reporteros/genética , Regiones Promotoras Genéticas , ARN Guía de Kinetoplastida/genética , Alineación de Secuencia , Programas Informáticos , Factores de Transcripción/química , Factores de Transcripción/genética , Proteínas Virales/química , Proteínas Virales/genética
4.
AJR Am J Roentgenol ; 213(6): W277-W286, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31414892

RESUMEN

OBJECTIVE. The objective of our study was to compare the quality and diagnostic utility of the following three metal artifact reduction sequences in evaluating hip arthroplasties: conventional multiacquisition variable-resonance image combination selective (MAVRIC SL), isotropic MAVRIC SL, and reduced-TR isotropic MAVRIC SL. SUBJECTS AND METHODS. Ninety-three hip arthroplasties (85 total hip replacements and eight hip resurfacings [nine bilateral hips]) in 84 patients (38 men and 46 women; mean age ± SD, 69.1 ± 9.7 years old) were imaged and evaluated. A calibration scan determined the number of spectral bins needed for each implant, and isotropic and conventional MAVRIC SL images were acquired. Reduced-TR isotropic MAVRIC SL scans were acquired for 40 arthroplasties. Two board-certified radiologists blinded to MRI acquisition evaluated images for clinical and image quality features and compared images using a mixed-effects ordinal logistic regression model and odds ratios. Rater agreement was assessed with Gwet agreement coefficients. Scanning times were compared using mixed-effects linear regression. Significance was set at p < 0.05. RESULTS. Calibration scans decreased the number of bins needed (median, 12 bins; interquartile range, 10-16 bins). Isotropic MAVRIC SL (mean scanning time, 7 minutes 16 seconds; 95% CI, 7 minutes 7 seconds-7 minutes 25 seconds) acquisitions had the longest scanning time, and conventional (mean, 5 minutes 46 seconds; 95% CI, 5 minutes 37 seconds-5 minutes 55 seconds) and reduced-TR isotropic (5 minutes 28 seconds; 95% CI, 5 minutes 15 seconds-5 minutes 41 seconds) MAVRIC SL acquisitions had scanning times that were similar. Both isotropic and reduced-TR isotropic MAVRIC SL images showed decreased blurring and improved visualization of the synovium and periprosthetic bone compared with conventional MAVRIC SL images (p < 0.001). Isotropic MAVRIC SL acquisitions more effectively improved signal-to-noise ratio (SNR), visualization of the synovium and periprosthetic bone, and lesion conspicuity and decreased blurring compared with reduced-TR isotropic MAVRIC SL acquisitions (p < 0.032). CONCLUSION. Isotropic MAVRIC SL acquisitions improve SNR, conspicuity of lesions, and visualization of synovium and periprosthetic bone and decrease blurring compared with conventional MAVRIC SL acquisitions.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Artefactos , Femenino , Humanos , Masculino , Metales , Persona de Mediana Edad , Relación Señal-Ruido
5.
Fish Shellfish Immunol ; 87: 449-459, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30703551

RESUMEN

Selenium (Se) is an essential micronutrient for human and animals. It plays an important role in antioxidative stress, selenoenzymes regulation and immunomodulation. In this study, two common immunostimulants chitosan (CTS) and Se were used to synthesize nanoparticles (CTS-SeNP). Immunomodulation of CTS-SeNP were explored in wild-type zebrafish (Danio rerio). Dietary supplementation of CTS-SeNP enhanced lysozyme activity, phagocytic respiratory burst as well as splenocytes proliferation stimulated by LPS and ConA. CTS-SeNP showed immunomodulation effect from 5 to 20 µg/g but the best outcome was observed at 10 µg/g. Immunomodulation effect were rapidly induced after 3-9d and can sustain to 60. The zebrafish fed with 10 µg/g CTS-SeNP also showed 26.7% higher survival rate than the control after intraperitoneal injection of common bacterium Aeromonas hydrophila. Our results suggested that CTS-SeNP is an effective immunostimulant to fish and has potential application in aquaculture.


Asunto(s)
Quitosano/metabolismo , Resistencia a la Enfermedad/efectos de los fármacos , Enfermedades de los Peces/inmunología , Inmunidad Innata/efectos de los fármacos , Nanopartículas , Selenio/metabolismo , Pez Cebra/inmunología , Aeromonas hydrophila/fisiología , Alimentación Animal/análisis , Animales , Quitosano/administración & dosificación , Dieta/veterinaria , Suplementos Dietéticos/análisis , Infecciones por Bacterias Gramnegativas/inmunología , Nanopartículas/administración & dosificación , Selenio/administración & dosificación
6.
Int J Adolesc Youth ; 19(3): 318-335, 2014 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-25364087

RESUMEN

This study draws on data from focus groups involving 50 young people from low-income families in Hong Kong to investigate their school-to-work experiences. In line with the ecological-developmental perspective, our results show that contextual influences, including lower levels of parental involvement and lack of opportunities for further education or skill development, constrain both the formulation and pursuit of educational and career goals. In contrast, service use and supportive interactions with parents and non-family adults were found to help young people find a career direction and foster more adaptive transition. Furthermore, our results indicate a striking difference in intrapersonal agency and coping styles between youths who were attending further education or engaged in jobs with career advancement opportunities and those who were not. We discuss the implications of our findings, both for future research and for policy development to enhance the school-to-work transition of economically disadvantaged young people.

7.
Cancers (Basel) ; 15(9)2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37173904

RESUMEN

Krüppel-like factors (KLFs) are transcription factors regulating various biological processes such as proliferation, differentiation, migration, invasion, and homeostasis. Importantly, they participate in disease development and progression. KLFs are expressed in multiple tissues, and their role is tissue- and context-dependent. KLF4 and KLF5 are two fascinating members of this family that regulate crucial stages of cellular identity from embryogenesis through differentiation and, finally, during tumorigenesis. They maintain homeostasis of various tissues and regulate inflammation, response to injury, regeneration, and development and progression of multiple cancers such as colorectal, breast, ovarian, pancreatic, lung, and prostate, to name a few. Recent studies broaden our understanding of their function and demonstrate their opposing roles in regulating gene expression, cellular function, and tumorigenesis. This review will focus on the roles KLF4 and KLF5 play in colorectal cancer. Understanding the context-dependent functions of KLF4 and KLF5 and the mechanisms through which they exert their effects will be extremely helpful in developing targeted cancer therapy.

8.
mSphere ; 7(1): e0100721, 2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-35107335

RESUMEN

The gut microbiome of an individual can shape the local environmental surface microbiome. We sought to determine how the intensive care unit (ICU) patient gut microbiome shapes the ICU room surface microbiome, focusing on vancomycin-resistant Enterococcus (VRE), a common ICU pathogen. This was an ICU-based prospective cohort study. Rectal swabs were performed in adult ICU patients immediately at the time of ICU admission and environmental surface swabs were performed at five predetermined time points. All swabs underwent 16S rRNA gene sequencing and culture for VRE. 304 ICU patients and 24 ICU rooms were sampled (5 longitudinal samples per ICU room). Spatially adjacent ICU rooms were no more microbially similar than nonadjacent rooms. Microbial signatures within rooms diverged rapidly over time: in 14 days, ICU rooms were as similar to other ICU rooms as they were to their prior selves. This divergence over time was more pronounced in rooms with higher patient turnover. Examining VRE status by culture, patient VRE gut colonization had modest agreement with room surface VRE (kappa statistic 0.36). There were no ICU rooms that consistently cultured positive for VRE, including those that housed VRE positive patients. Individual ICU patients had a limited impact on ICU room surface microbiome, and rooms diverged similarly over time regardless of patients. Patient VRE gut colonization may have a modest influence on room surface VRE but there were no "bad rooms" that consistently cultured positive for VRE. These results may be useful in planning infection control measures. IMPORTANCE This study found that intensive care unit (ICU) room microbial signatures diverged from their baseline quickly: within 2 weeks, individual ICU rooms had lost distinguishing characteristics and were as similar to other ICU rooms as they were to their former selves. Patient turnover within rooms accelerated this drift. Patient gut colonization with vancomycin-resistant Enterococcus (VRE) was associated with ICU room surface contamination with VRE; again, within 2 weeks, this association was substantially diminished. These results provide dynamic information regarding how patients control the microbiota on local hospital room surfaces and may facilitate decision making for infection prevention and control measures targeting VRE or other organisms.


Asunto(s)
Infección Hospitalaria , Microbioma Gastrointestinal , Infecciones por Bacterias Grampositivas , Enterococos Resistentes a la Vancomicina , Adulto , Infección Hospitalaria/prevención & control , Infecciones por Bacterias Grampositivas/prevención & control , Humanos , Unidades de Cuidados Intensivos , Estudios Prospectivos , ARN Ribosómico 16S/genética , Vancomicina , Resistencia a la Vancomicina
9.
Int J Psychol ; 46(3): 234-40, 2011 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-22044236

RESUMEN

The relationship between personality, social functioning, and depression remains unclear. The present study employs structural equation modeling to examine the mediating role of social functioning between harm avoidance (HA), self-directedness (SD), and depression. A sample of 902 individuals completed a self-report questionnaire consisting of the following scales: HA and SD subscales of the Temperament and Character Inventory (TCI), Beck Depression Inventory (BDI), and Social Adaptation Self-Evaluation Scale (SASS). Structural equation modeling via analysis of moment structure was used to estimate the fit of nine related models. Results indicated that social functioning is a mediator between harm avoidance or self-directness and depression. Self-directedness was also shown to have direct effects on depression. The results support the social reinforcement theory of depression and provide a theoretical account of how the variables are related based on correlation methods. Suggestions are offered for future experimental and longitudinal research.


Asunto(s)
Carácter , Trastorno Depresivo/psicología , Modelos Psicológicos , Ajuste Social , Adolescente , Adulto , Trastorno Depresivo/diagnóstico , Femenino , Reducción del Daño , Hong Kong , Humanos , Control Interno-Externo , Masculino , Persona de Mediana Edad , Inventario de Personalidad/estadística & datos numéricos , Refuerzo Social , Autoeficacia , Estudiantes/psicología , Adulto Joven
10.
HSS J ; 17(2): 165-173, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34421426

RESUMEN

Background: Hip arthroplasty is increasingly prevalent, and early detection of complications can improve outcomes. Quantitative magnetic resonance imaging (qMRI) methods using multi-acquisition variable-resonance image combination (MAVRIC) may allow for the assessment of soft tissues in close proximity to hip arthroplasty devices. Question/Purposes: We sought to determine the clinical feasibility of MAVRIC-based T2 mapping as a qMRI approach for assessing synovial reactions in patients with a hip arthroplasty device. We hypothesized that there would be differences in T2 metrics by synovial type, clinical impression, and clinical findings related to synovitis. Methods: We conducted a cross-sectional study of 141 subjects with 171 hip arthroplasties with greater than 1 year post-implantation. We enrolled subjects who had had a primary total hip arthroplasty or hip resurfacing arthroplasty between May 2019 and March 2020, excluding those with a revision hip arthroplasty and those with standard safety contraindications for receiving an MRI. Institutional standard 2D fast spin echo (FSE), short-tau inversion recovery (STIR), and susceptibility-reduced MAVRIC morphological MR images were acquired for each hip and followed by a dual-echo acquisition MAVRIC T2 mapping sequence. Results: While 131 subjects (81%) were classified as having a "normal" synovial reaction, significantly longer T2 values were found for fluid synovial reactions compared with mixed reactions. In addition, subjects with synovial dehiscence and decompression present had T2 prolongation. Larger synovial volumes were found in subjects with low-signal intensity deposits. Conclusions: MAVRIC-based T2 mapping is clinically feasible and there are significant quantitative differences based on type of synovial reaction. Patients undergoing hip arthroscopy revision surgery will warrant comparison of T2 values with direct histologic assessment of a tissue sample obtained intraoperatively. The approach used in this study may be used for a quantitative evaluation and monitoring of soft tissues around metal implants.

11.
Can J Hosp Pharm ; 73(1): 37-44, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32109959

RESUMEN

BACKGROUND: Currently, there is no standardized approach to the frequency of monitoring tacrolimus levels in patients who have undergone hematopoietic stem cell transplant (HSCT). Previously, the practice at the study hospital was to monitor tacrolimus levels daily throughout a patient's admission. A recent institutional study suggested that measurement of tacrolimus level is more frequent than needed to achieve consistent time in the therapeutic range (TTR), particularly after the first 7 days. As a result, tacrolimus monitoring was changed to daily measurement for the initial week of therapy, followed by measurements on Monday, Wednesday, and Friday in subsequent weeks. OBJECTIVE: To confirm the safety and efficacy of the recent practice change. METHODS: This retrospective chart review of HSCT patients admitted to The Ottawa Hospital involved 68 patients in the pre-practice change group and 43 patients in the post-practice change group. Data on tacrolimus measurement were collected for up to 21 days after initiation of this medication. The proportion of TTR was compared between the 2 groups. Differences in the incidence and severity of renal dysfunction and the incidence of acute graft versus host disease (GVHD) were determined and described. RESULTS: In the pre-practice change cohort, the median proportion of TTR for tacrolimus was 40.5% for days 1-7, 65.1% for days 8-14, and 78.9% for days 15-21, similar to the values for the post-practice change group (46.6% [p = 0.09], 62.9% [p = 0.93], and 70.0% [p = 0.22], respectively, for the same periods). The incidence of acute GVHD within 100 days after HSCT was 24% and 33% for the pre- and post-practice change cohorts, respectively. The incidence and severity of renal dysfunction were similar between the 2 groups. CONCLUSION: The proportion of TTR for tacrolimus was not significantly affected by the recent practice change. Similarly, the incidence and severity of renal dysfunction and the incidence of acute GVHD did not appear to differ between the pre- and post-practice change groups.


CONTEXTE: Il n'existe actuellement aucune approche standardisée portant sur la fréquence des contrôles des valeurs du tacrolimus pour les patients ayant subi une greffe de cellules souches hématopoïétiques (GCSH). Dans le passé, la pratique à l'hôpital où s'est déroulée l'étude consistait à les contrôler quotidiennement durant tout le séjour du patient. Une récente étude institutionnelle a laissé entendre que cette mesure était plus fréquente que nécessaire pour obtenir une marge thérapeutique régulière (TTR), particulièrement après les sept premiers jours. Par conséquent, une modification du contrôle des valeurs du tacrolimus préconise désormais des mesures quotidiennes pendant la première semaine de la thérapie, suivies de mesures le lundi, le mercredi et le vendredi au cours des semaines suivantes. OBJECTIF: Confirmer la sécurité et l'efficacité du récent changement apporté à la pratique. MÉTHODE: Cet examen rétrospectif des dossiers des patients GCSH admis à l'Hôpital d'Ottawa concernait 68 patients du groupe « avant le changement de pratique ¼ et 43 du groupe « après le changement de pratique ¼. Les données relatives aux mesures des valeurs du tacrolimus ont été recueillies pendant les 21 premiers jours après le début de l'administration de ce médicament. La comparaison entre les deux groupes portait sur la proportion de TTR. Les différences d'incidence et de gravité du dysfonctionnement rénal et l'apparition de réaction aiguë du greffon contre l'hôte (GVHD) ont été définies et décrites. RÉSULTATS: Dans la cohorte « avant le changement de pratique ¼, la proportion moyenne de TTR du tacrolimus était de 40,5 % du 1er au 7e jour; de 65,1 % du 8e au 14e jour et de 78,9 % du 15e au 21e jour. Ces valeurs sont similaires à celles du groupe « après le changement de pratique ¼ (respectivement 46,6 % [p = 0,09], 62,9 % [p = 0,93] et 70,0 % [p = 0,22] pendant les mêmes périodes). L'incidence de réaction aiguë du greffon contre l'hôte dans les 100 jours après la GCSH se montait respectivement à 24 % et à 33 % dans les cohortes « avant et après le changement de pratique ¼. L'incidence et la gravité du dysfonctionnement rénal étaient similaires dans les deux groupes. CONCLUSION: La proportion de TTR relative au tacrolimus n'a pas été modifiée de manière significative par le changement récent de pratique. De même, l'incidence et la gravité du dysfonctionnement rénal et l'incidence de réaction aiguë du greffon contre l'hôte ne semblaient pas différer entre les groupes avant et après le changement de pratique.

12.
Cell Syst ; 2(4): 260-71, 2016 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-27135538

RESUMEN

Pleiotropic regulatory mutations affect diverse cellular processes, posing a challenge to our understanding of genotype-phenotype relationships across multiple biological scales. Adaptive laboratory evolution (ALE) allows for such mutations to be found and characterized in the context of clear selection pressures. Here, several ALE-selected single-mutation variants in RNA polymerase (RNAP) of Escherichia coli are detailed using an integrated multi-scale experimental and computational approach. While these mutations increase cellular growth rates in steady environments, they reduce tolerance to stress and environmental fluctuations. We detail structural changes in the RNAP that rewire the transcriptional machinery to rebalance proteome and energy allocation toward growth and away from several hedging and stress functions. We find that while these mutations occur in diverse locations in the RNAP, they share a common adaptive mechanism. In turn, these findings highlight the resource allocation trade-offs organisms face and suggest how the structure of the regulatory network enhances evolvability.


Asunto(s)
Mutación Puntual , Adaptación Fisiológica , Evolución Biológica , ARN Polimerasas Dirigidas por ADN , Escherichia coli , Proteínas de Escherichia coli , Evolución Molecular , Fenotipo
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