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1.
Clin Cancer Res ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916900

RESUMO

TGFß is a pleiotropic signaling pathway, which plays a pivotal role in regulating a multitude of cellular functions. TGFß has a dual role in cell regulation where it induces growth inhibition and cell death; however, it can switch to a growth-promoting state under cancerous conditions. TGFß is upregulated in CRC and pancreatic cancer, altering the tumor microenvironment, immune system, and promoting a mesenchymal state. The upregulation of TGFß in certain cancers leads to resistance to immunotherapy, and attempts to inhibit TGFß expression have led to reduced therapeutic resistance when combined with chemo- and immunotherapy. Here, we review the current TGFß inhibitor drugs in clinical trials for pancreatic and colorectal cancer, with the goal of uncovering advances in improving clinical efficacy for TGFß combinational treatments in patients. Furthermore, we discuss the relevance of alterations in TGFß signaling and germline variants in the context of personalizing treatment for patients who show lack of response to current therapeutics.

2.
Microbiol Resour Announc ; 12(9): e0053023, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37578226

RESUMO

We report the complete genome assembly of Pediococcus acidilactici A40, a bacterium with biocontrol and plant growth-promoting properties, obtained from Colombia.

3.
rev. psicogente ; 25(48): 177-203, jul.-dic. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1424782

RESUMO

Resumen Objetivo: Identificar en qué medida la salud mental y bienestar subjetivo son predichas por el endeudamiento por motivos de estudio en estudiantes universitarios de la ciudad de Temuco, Chile. Método: Una muestra no probabilística de 151 estudiantes universitarios de quinto año o superior de su respectiva carrera universitaria respondió a medidas de salud mental (DASS-21), de bienestar subjetivo (satisfacción con la vida y felicidad subjetiva), y del nivel de endeudamiento asumido para financiar sus estudios universitarios. Los análisis incluyeron regresiones lineales múltiples jerárquicas donde se incluyeron como variables independientes la variable género en un primer paso y el endeudamiento por créditos universitarios en el segundo paso. En cada regresión se incluyó un factor de salud mental y de bienestar subjetivo como variable dependiente. Resultados: Resultados indican que el endeudamiento por motivos de estudio predice significativa- mente satisfacción con la vida (F(2, 148) = 5,95, p = 0,003, R2Adjusted = 0,06; β =-0,16, p = 0,049), pero no predice felicidad subjetiva (p = n.s.) (factores de bienestar subjetivo), sintomatología depresiva (p = n.s.), ansiosa (p = n.s.), ni estrés (p = n.s.) (factores de salud mental). Conclusión: Resultados del estudio sugieren que los estudiantes universitarios pudieran percibir el endeudamiento estudiantil como una inversión hacia el futuro lo que pudiera operar como un factor protector de su salud mental y bienestar subjetivo.


Abstract Objective: To evaluate if debt due to university loans predicts mental health and subjective well-being in university students of Temuco, Chile. Method: A non-probabilistic sample of 151 last-year university students completed measures of mental health (DASS-21), of subjective well-being (satisfaction with life, and subjective happiness), and debt levels due to student loans. Analyses included hierarchical multiple linear regressions where gender was entered in a first step and debt due to university loans on a second step as independent variables. Each regression considered a factor of mental health or a factor of subjective well-being as the dependent variable. Results: Results show that debt due to university loans predict predicts satisfaction with life (F(2, 148) = 5,95, p = 0,003, R2Adjusted = 0,06; β =-0,16, p = 0,049), but not subjective happiness (p = n.s.) (factors of subjective well-being), nor symptoms of depression (p = n.s.), anxiety (p = n.s.), or stress (p = n.s.) (factors of mental health). Conclusion: Results of this study suggest that university students may perceive student debt as an investment which may act as a protective factor of their mental health and subjective well-being.

4.
NPJ Breast Cancer ; 8(1): 84, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853889

RESUMO

There is growing evidence that germline mutations in certain genes influence cancer susceptibility, tumor evolution, as well as clinical outcomes. Identification of a disease-causing genetic variant enables testing and diagnosis of at-risk individuals. For breast cancer, several genes such as BRCA1, BRCA2, PALB2, ATM, and CHEK2 act as high- to moderate-penetrance cancer susceptibility genes. Genotyping of these genes informs genetic risk assessment and counseling, as well as treatment and management decisions in the case of high-penetrance genes. TGFBR1*6A (rs11466445) is a common variant of the TGF-ß receptor type I (TGFBR1) that has a global minor allelic frequency (MAF) of 0.051 according to the 1000 Genomes Project Consortium. It is emerging as a high frequency, low penetrance tumor susceptibility allele associated with increased cancer risk among several cancer types. The TGFBR1*6A allele has been associated with increased breast cancer risk in women, OR 1.15 (95% CI 1.01-1.31). Functionally, TGFBR1*6A promotes breast cancer cell proliferation, migration, and invasion through the regulation of the ERK pathway and Rho-GTP activation. This review discusses current findings on the genetic, functional, and mechanistic associations between TGFBR1*6A and breast cancer risk and proposes future directions as it relates to genetic association studies and mechanisms of action for tumor growth, metastasis, and immune suppression.

5.
Front Microbiol ; 13: 813002, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35401437

RESUMO

Cattle productivity depends on our ability to fully understand and manipulate the fermentation process of plant material that occurs in the bovine rumen, which ultimately leads to the improvement of animal health and increased productivity with a reduction in environmental impact. An essential step in this direction is the phylogenetic and functional characterization of the microbial species composing the ruminal microbiota. To address this challenge, we separated a ruminal fluid sample by size and density using a sucrose density gradient. We used the full sample and the smallest fraction (5%), allowing the enrichment of bacteria, to assemble metagenome-assembled genomes (MAGs). We obtained a total of 16 bacterial genomes, 15 of these enriched in the smallest fraction of the gradient. According to the recently proposed Genome Taxonomy Database (GTDB) taxonomy, these MAGs belong to Bacteroidota, Firmicutes_A, Firmicutes, Proteobacteria, and Spirochaetota phyla. Fifteen MAGs were novel at the species level and four at the genus level. The functional characterization of these MAGs suggests differences from what is currently known from the genomic potential of well-characterized members from this complex environment. Species of the phyla Bacteroidota and Spirochaetota show the potential for hydrolysis of complex polysaccharides in the plant cell wall and toward the production of B-complex vitamins and protein degradation in the rumen. Conversely, the MAGs belonging to Firmicutes and Alphaproteobacteria showed a reduction in several metabolic pathways; however, they have genes for lactate fermentation and the presence of hydrolases and esterases related to chitin degradation. Our results demonstrate that the separation of the rumen microbial community by size and density reduced the complexity of the ruminal fluid sample and enriched some poorly characterized ruminal bacteria allowing exploration of their genomic potential and their functional role in the rumen ecosystem.

6.
Crit Rev Biotechnol ; 42(7): 1028-1044, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34706613

RESUMO

The use of bacterial inoculants for ensiling based on lactic acid bacteria (LAB) to obtain conserved forages has become an alternative for the improvement of milk and meat productivity in cattle, specifically by optimizing the nutritional and microbial quality of animal feed. LAB inoculant production involves microbial and technological aspects such as biomass obtention, the use of cocultures, the inclusion of probiotics, the production of antimicrobial peptides, operational methods used in bioreactors, and the formulation of the end product to be commercialized to farmers. This review explores the technical aspects of the manufacture of bacterial inoculants, from the main features desired in LAB for ensiling purposes to the alternatives of the bioprocess involved.


Assuntos
Inoculantes Agrícolas , Lactobacillales , Animais , Bovinos , Fermentação , Ácido Láctico , Lactobacillus , Silagem/análise , Silagem/microbiologia
7.
Genes (Basel) ; 12(10)2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34680981

RESUMO

The American tropics are hotspots of wild and domesticated plant biodiversity, which is still underutilized by breeding programs despite being conserved at regional gene banks. The improvement of those programs depends on long-term public funds and the maintenance of specialized staff. Unfortunately, financial ups and downs complicate staff connectivity and their research impact. Between 2000 and 2010, Agrosavia (Corporación Colombiana de Investigación Agropecuaria) dramatically decreased its public financial support. In 2017, we surveyed all 52 researchers from Agrosavia involved in plant breeding and plant genetic resource programs to examine the effect of decimating funds in the last ten years. We hypothesized that the staff dedicated to plant breeding still suffer a strong fragmentation and low connectivity. As we expected, the social network among researchers is weak. The top ten central leaders are predominantly males with an M.Sc. degree but have significant experience in the area. The staff has experience in 31 tropical crops, and 17 are on the list of underutilized species. Moreover, although 26 of these crops are in the national germplasm bank, this has not been the primary source for their breeding programs. We proposed five principles to improve connectivity among teams and research impact: (1) The promotion of internal discussion about gender gaps and generation shifts to design indicators to monitor and decrease this disparity over time. (2) The construction of long-term initiatives and synergies with the Colombian government to support the local production of food security crops independent of market trends. (3) Better collaboration between the National Plant Germplasm Bank and plant breeding researchers. (4) A concerted priority list of species (especially those neglected or underutilized) and external institutions to better focus the collaborative efforts in research using public funds. (5) Better spaces for the design of projects among researchers and training programs in new technologies. These principles could also apply in other tropical countries with public plant breeding research programs facing similar challenges.


Assuntos
Genes de Plantas , Melhoramento Vegetal , Plantas/genética , Clima Tropical , Adulto , Biodiversidade , Colômbia , Produtos Agrícolas/genética , Feminino , Humanos , Masculino , Pesquisadores
8.
Front Microbiol ; 12: 664754, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34305833

RESUMO

The ruminal microbial community is an important element in health, nutrition, livestock productivity, and climate impact. Despite the historic and current efforts to characterize this microbial diversity, many of its members remain unidentified, making it challenging to associate microbial groups with functions. Here we present a low-cost methodology for rumen sample treatment that separates the microbial community based on cell size, allowing for the identification of subtle compositional changes. In brief, the sample is centrifuged through a series of sucrose density gradients, and cells migrate to their corresponding density fraction. From each fraction, DNA is extracted and 16S rRNA gene amplicons are sequenced. We tested our methodology on four animals under two different conditions, fasting, and post-feeding. Each fraction was examined by confocal microscopy showing that the same sucrose fraction consistently separated similar cell-sized microorganisms independent of the animal or treatment. Microbial composition analysis using metabarcoding showed that our methodology detected low abundance bacterial families and population changes between fasting and post-feeding treatments that could not be observed by bulk DNA analysis. In conclusion, the sucrose-based method is a powerful low-cost approximation to untwine, enrich, and potentially isolate uncharacterized members of the ruminal microbiome.

9.
Rev. costarric. cardiol ; 23(1)jun. 2021.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1389033

RESUMO

Resumen Introducción y objetivo: Comunicar el primer informe del del registro nacional de dispositivos de estimulación cardíaca de agosto 2019 a agosto 2020, registro prospectivo de participación voluntaria. Métodos: Se analiza la información registrada, en forma voluntaria, por los centros implantadores con respecto a la población de pacientes a quienes se implantó un marcapaso, un desfibrilador o un resincronizador entre el 22 de agosto de 2019 hasta setiembre de 2020. Resultados: Se registraron un total de 317 procedimientos de marcapasos, por 10 centros implantadores, lo que corresponde a una participación en el registro de un 40%. La tasa de uso de marcapasos de 6,27 x 100 mil habitantes. Un 83% de los marcapasos fueron implantados en centros públicos, un 70% correspondió a dispositivos bicamerales. La edad media de la población fue de 73,7 años. La indicación más frecuente fue el trastorno de conducción AV (70,3%). Los electrodos de fijación activa fueron los más utilizados (97,8%). Un 83,3% de los sistemas implantados tuvieron compatibilidad con resonancia magnética. El uso de marcapasos unicamerales fue más frecuente en pacientes con 80 o más años. Con respecto a la terapia DAI se registraron un total de 63 procedimientos, por 5 centros implantadores, con una participación del 41%. La tasa total de implantes durante el período fue de 1,25 x 100 mil habitantes. La cardiomiopatía dilatada no isquémica fue la cardiopatía más frecuente en la población registrada. Conclusiones: El registro permite conocer la dinámica de procedimientos e indicaciones más usuales para el uso de dispositivos electrónicos cardíacos así como establecer la tasa de uso de las terapias en nuestro país. El porcentaje de participación en el registro puede mejorar. La implantación de dispositivos de estimulación cardíaca es financiada predominantemente por el sistema de seguridad social. La tasa de implantación es baja con respecto a otras regiones.


Abstract Costa Rican Registry of Resynchronizers, Automatic Defibrillators and Endovascular Pacemakers (RECORDAME). I Official Report of the Electrophysiology Commission of the Costa Rican Cardiology Association (2019-2020) Introduction and objective: To communicate the results of the first national registry of cardiac stimulation devices from August 2019 to August 2020. Methods: We analyze the information recorded prospectively, on a voluntary basis, by the implant centers with respect to the population of patients who were implanted with a pacemaker, a defibrillator or a resynchronizer between August 22, 2019 and September 2020. Results: A total of 317 pacemaker procedures were registered from 10 centers participated. Participation was 40% of total procedures reported by companies. The pacemaker implantation rate was 6.27 per hundred thousand. A 83% of pacemakers were implanted in public centers, 70% corresponded to dual chamber devices. Mean age of the population was 73.7 years. Most frequent indication was AV conduction disorder (70.3%). Active fixation electrodes were the most used (97.8%). A 83.3% were MRI conditional. Use of single chamber pacemakers was more frequent in patients aged 80 years or older. Regarding ICD therapy, a total of 63 procedures were registered. from 5 centers, with a participation of 41%. Rate of ICD use was 1.25 per hundred thousand. Non-ischemic dilated cardiomyopathy was the most common heart disease in the recorded population. Conclusions: The registry allowed to know the frequency of procedures and more usual indications as well as to establish the rate of use of therapies in our country. The percentage of participation in the registration can be improved. The implementation of cardiac stimulation devices is predominantly financed by the social security system. The implantation rate is low compared to other regions.


Assuntos
Humanos , Masculino , Feminino , Marca-Passo Artificial/estatística & dados numéricos , Sistema de Registros , Desfibriladores Implantáveis/estatística & dados numéricos , Costa Rica , Dispositivos de Terapia de Ressincronização Cardíaca/estatística & dados numéricos
10.
Front Microbiol ; 12: 744075, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35035382

RESUMO

Traditionally, starting inoculants have been applied to improve ensiling of forage used for livestock feed. Here, we aimed to build up a bioinoculant composed of lactic acid-producing and lignocellulolytic bacteria (LB) derived from the Megathyrsus maximus (guinea grass) phyllosphere. For this, the dilution-to-stimulation approach was used, including a sequential modification of the starting culture medium [Man, Rogosa, and Sharpe (MRS) broth] by addition of plant biomass (PB) and elimination of labile carbon sources. Along 10 growth-dilution steps (T1-T10), slight differences were observed in terms of bacterial diversity and composition. After the sixth subculture, the consortium started to degrade PB, decreasing its growth rate. The co-existence of Enterobacteriales (fast growers and highly abundance), Actinomycetales, Bacillales, and Lactobacillales species was observed at the end of the selection process. However, a significant structural change was noticed when the mixed consortium was cultivated in higher volume (500ml) for 8days, mainly increasing the proportion of Paenibacillaceae populations. Interestingly, Actinomycetales, Bacillales, and Lactobacillales respond positively to a pH decrease (4-5), suggesting a relevant role within a further silage process. Moreover, gene-centric metagenomic analysis showed an increase of (hemi)cellulose-degrading enzymes (HDEs) during the enrichment strategy. Reconstruction of metagenome-assembled genomes (MAGs) revealed that Paenibacillus, Cellulosimicrobium, and Sphingomonas appear as key (hemi)cellulolytic members (harboring endo-glucanases/xylanases, arabinofuranosidases, and esterases), whereas Enterococcus and Cellulosimicrobium have the potential to degrade oligosaccharides, metabolize xylose and might produce lactic acid through the phosphoketolase (PK) pathway. Based on this evidence, we conclude that our innovative top-down strategy enriched a unique bacterial consortium that could be useful in biotechnological applications, including the development/design of a synthetic bioinoculant to improve silage processes.

11.
Mol Carcinog ; 60(1): 60-70, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33283918

RESUMO

Ultraviolet (UV) B irradiation of the skin induces acute inflammation, as characterized by erythema, edema, and immunosuppression, and is subsequently linked to the progression of skin cancer. Toll-like receptor 4 (TLR4), a component of innate immunity, has been shown to play an important role in cancer. To elucidate the role of TLR4 in UVB-induced tumor development, TLR4-proficient (C3H/HeN) and TLR4-deficient (C3H/HeJ) mice were exposed to multiple doses of UVB radiation (200 mJ/cm2 ) for 40 weeks. Photocarcinogenesis was retarded in terms of tumor incidence, and tumor latency, in mice deficient in TLR4 compared with TLR4-proficient mice, whereas significantly greater numbers of tumors occurred in TLR4-proficient mice. There was significant upregulation of inflammatory markers like COX-2, PGE2 , S100A8, and S100A9 in the skin of TLR4-proficient mice than the skin of TLR4-deficient mice. Furthermore, we found that TLR4-proficient mice had a significantly higher number of Gr1+CD11b+ myeloid cells CD4+CD25+ regulatory T-cells than TLR4-deficient mice. Furthermore, the levels of interferon (IFN)-γ cytokine was increased and the levels of interleukin (IL)-4, IL-10, and IL-17 cytokines were decreased in serum, skin, and tumor lysates of TLR4-deficient mice in comparison with samples from TLR4-proficient mice. Together, our data indicate that TLR4-mediated inflammation may cause suppression of antitumor responses and trigger the development of UVB-induced skin cancers. Thus, strategies to inhibit TLR4-mediated immune suppression may allow us to develop preventive and therapeutic approaches for the management of UVB-induced cutaneous tumors.


Assuntos
Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/genética , Receptor 4 Toll-Like/genética , Raios Ultravioleta/efeitos adversos , Animais , Carcinogênese/genética , Carcinogênese/imunologia , Carcinogênese/efeitos da radiação , Deleção de Genes , Imunidade , Inflamação/etiologia , Inflamação/genética , Inflamação/imunologia , Camundongos , Neoplasias Cutâneas/imunologia , Receptor 4 Toll-Like/imunologia
12.
Microorganisms ; 8(11)2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187375

RESUMO

Anaerobic fungi in the gut of domesticated and wild mammalian herbivores play a key role in the host's ability to utilize plant biomass. Due to their highly effective ability to enzymatically degrade lignocellulose, anaerobic fungi are biotechnologically interesting. Numerous factors have been shown to affect the ability of anaerobic fungi to break down plant biomass. However, methods to reduce the non-productive lag time in batch cultures and the effect of leaf-blade cut-length and condition on the fungal fermentation are not known. Therefore, experimentation using a novel gas production approach with pre-grown, axenic cultures of Neocallimastix frontalis was performed using both fresh and air-dried perennial ryegrass leaf-blades of different cut-lengths. The methodology adopted removed the lag-phase and demonstrated the digestion of un-autoclaved leaf-blades. Fermentation of leaf-blades of 4.0 cm cut-length produced 18.4% more gas yet retained 11.2% more apparent DM relative to 0.5 cm cut-length leaf-blades. Drying did not affect fermentation by N. frontalis, although an interaction between drying and leaf-blade cut-length was noted. Removal of the lag phase and the use of un-autoclaved substrates are important when considering the biotechnological potential of anaerobic fungi. A hypothesis based upon sporulation at cut surfaces is proposed to describe the experimental results.

13.
Int Wound J ; 17(6): 1642-1649, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32691532

RESUMO

Fournier's Gangrene is a fulminating necrotizing fasciitis of the perineum and genitalia. Standard treatment involves immediate excision of all necrotic tissue, aggressive antibiotic coverage, and supportive medical care. Still, the infection is commonly fatal or disfiguring. Wound treatment with disinfected blowfly larvae (maggot debridement therapy or MDT) has been shown to be highly effective, with multiple studies demonstrating effective debridement, disinfection, and promotion of granulation tissue. MDT also has been associated with preservation of viable tissue and minimised blood loss. This report describes a prospective clinical study of MDT for Fournier's gangrene aimed to test the hypothesis that early use of maggots could decrease the number of surgical treatments required to treat Fournier's gangrene. Subjects were provided with one initial surgical excision, followed by debridement using only medical grade Lucilia sericata larvae. Only two subjects were enrolled, both diabetic men. Intensive care and culture-directed antimicrobial coverage were administered as usual. Maggot debridement was associated with the disappearance of necrotic tissue, control of infection and granulation tissue growth. In both subjects, wounds healed without requiring further surgical resection or anatomical reconstruction. Maggot therapy decreased the number of surgical procedures that otherwise would have been necessary, and led to favourable outcomes.


Assuntos
Calliphoridae , Desbridamento/métodos , Gangrena de Fournier , Larva , Animais , Gangrena de Fournier/terapia , Humanos , Masculino , Estudos Prospectivos
16.
Rev. costarric. cardiol ; 21(2)jul.-dic. 2019.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1508119

RESUMO

Introducción. La estimulación apical del ventrículo derecho (VD) produce un patrón de activación similar al bloqueo de rama izquierda, el cual retrasa la activación de la pared lateral del ventrículo izquierdo. El "índice de disincronía" (ID) correlaciona las derivadas DII y V6 como marcadores de la despolarización septal y lateral; en el presente reporte, se utilizó el ID para el implante del electrodo ventricular en la región "parahisiana". Métodos. Se incluyeron 6 pacientes a quienes se realizó un implante electivo de marcapasos bicameral, bajo indicaciones convencionales. En cada paciente se registró un electrocardiograma de 12 derivaciones en reposo, bajo estimulación apical en el (VD) y bajo estimulación septal "parahisiana"; en cada uno se obtuvo el ID. Resultados. Se analizaron 18 electrocardiogramas de 6 pacientes, edad promedio 72±16.7 años (48-91) 2 mujeres; en 4, la indicación del implante fue bloqueo atrioventricular completo y en 2, enfermedad del nodo sinusal. En todos los pacientes se observó mejoría del ID con estimulación parahisiana, con respecto al ápex del VD y en la mayoría también con respecto al ritmo de base. No se observó correlación entre la duración del complejo QRS y el ID. Conclusión. El uso del ID utilizando las derivaciones II/V6 permite valorar la disincronía eléctrica, en forma sencilla, no invasiva y en tiempo real.


Introduction. Right ventricle (RV) apical stimulation produces an activation pattern similar to the left bundle Branch block, which delays the lateral wall of the left ventricle activation. The "dyssynchrony index" (ID) correlates DII and V6 leads as surrogate markers of septal and lateral depolarization; in this report, the ID for the ventricular electrode implantin the "parahisian" region was used. Methods. Six patients were included who underwent an elective dual chamber pacemaker implant, under conventional indications. In each patient, a 12-lead electrocardiogram was recorded at rest, under RV apical stimulation and under "parahisian" septal stimulation; in each one, the ID was obtained. Results. Eighteen electrocardiograms of 6 patients were analysed, average age 72 ± 16.7 years (48-91) 2 women; in 4, the indication of the implant was complete atrioventricular block and in 2, sinus node disease. In all patients, improvement of the ID with parahisian stimulation was observed, with respect to the RV apex, and in most of them, also with respect to the base rhythm. No correlation was observed between the QRS complex duration and the ID. Conclusión The use of the ID using leads II/V6 allows the evaluation of electrical dyssynchrony, in a simple, non-invasive way and in real time.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Marca-Passo Artificial , Estimulação Cardíaca Artificial , Costa Rica
17.
EBioMedicine ; 44: 209-224, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31160272

RESUMO

BACKGROUND: Administration of amplitude modulated 27·12 MHz radiofrequency electromagnetic fields (AM RF EMF) by means of a spoon-shaped applicator placed on the patient's tongue is a newly approved treatment for advanced hepatocellular carcinoma (HCC). The mechanism of action of tumour-specific AM RF EMF is largely unknown. METHODS: Whole body and organ-specific human dosimetry analyses were performed. Mice carrying human HCC xenografts were exposed to AM RF EMF using a small animal AM RF EMF exposure system replicating human dosimetry and exposure time. We performed histological analysis of tumours following exposure to AM RF EMF. Using an agnostic genomic approach, we characterized the mechanism of action of AM RF EMF. FINDINGS: Intrabuccal administration results in systemic delivery of athermal AM RF EMF from head to toe at levels lower than those generated by cell phones held close to the body. Tumour shrinkage results from differentiation of HCC cells into quiescent cells with spindle morphology. AM RF EMF targeted antiproliferative effects and cancer stem cell inhibiting effects are mediated by Ca2+ influx through Cav3·2 T-type voltage-gated calcium channels (CACNA1H) resulting in increased intracellular calcium concentration within HCC cells only. INTERPRETATION: Intrabuccally-administered AM RF EMF is a systemic therapy that selectively block the growth of HCC cells. AM RF EMF pronounced inhibitory effects on cancer stem cells may explain the exceptionally long responses observed in several patients with advanced HCC. FUND: Research reported in this publication was supported by the National Cancer Institute's Cancer Centre Support Grant award number P30CA012197 issued to the Wake Forest Baptist Comprehensive Cancer Centre (BP) and by funds from the Charles L. Spurr Professorship Fund (BP). DWG is supported by R01 AA016852 and P50 AA026117.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Cálcio/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/terapia , Magnetoterapia , Animais , Bloqueadores dos Canais de Cálcio/farmacologia , Carcinoma Hepatocelular/patologia , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/patologia , Magnetoterapia/métodos , Camundongos , Células-Tronco Neoplásicas/metabolismo , Especificidade de Órgãos , RNA Interferente Pequeno/genética , Radiometria , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
18.
EBioMedicine ; 44: 194-208, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31129098

RESUMO

BACKGROUND: Brain metastases are a major cause of death in patients with metastatic breast cancer. While surgical resection and radiation therapy are effective treatment modalities, the majority of patients will succumb from disease progression. We have developed a novel therapy for brain metastases that delivers athermal radiofrequency electromagnetic fields that are amplitude-modulated at breast cancer specific frequencies (BCF). METHODS: 27.12 MHz amplitude-modulated BCF were administered to a patient with a breast cancer brain metastasis by placing a spoon-shaped antenna on the anterior part of the tongue for three one-hour treatments every day. In preclinical models, a BCF dose, equivalent to that delivered to the patient's brain, was administered to animals implanted with either brain metastasis patient derived xenografts (PDXs) or brain-tropic cell lines. We also examined the efficacy of combining radiation therapy with BCF treatment. Additionally, the mechanistic underpinnings associated with cancer inhibition was identified using an agnostic approach. FINDINGS: Animal studies demonstrated a significant decrease in growth and metastases of brain-tropic cell lines. Moreover, BCF treatment of PDXs established from patients with brain metastases showed strong suppression of their growth ability. Importantly, BCF treatment led to significant and durable regression of brain metastasis of a patient with triple negative breast cancer. The tumour inhibitory effect was mediated by Ca2+ influx in cancer cells through CACNA1H T-type voltage-gated calcium channels, which, acting as the cellular antenna for BCF, activated CAMKII/p38 MAPK signalling and inhibited cancer stem cells through suppression of ß-catenin/HMGA2 signalling. Furthermore, BCF treatment downregulated exosomal miR-1246 level, which in turn decreased angiogenesis in brain environment. Therefore, targeted growth inhibition of breast cancer metastases was achieved through CACNA1H. INTERPRETATION: We demonstrate that BCF, as a single agent or in combination with radiation, is a novel treatment approach to the treatment of brain metastases. This paradigm shifting modality warrants further clinical trials for this unmet medical need.


Assuntos
Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/secundário , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Canais de Cálcio Tipo T/metabolismo , Cálcio/metabolismo , Magnetoterapia , Animais , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Campos Eletromagnéticos , Feminino , Perfilação da Expressão Gênica , Proteína HMGA2 , Humanos , Imuno-Histoquímica , Sistema de Sinalização das MAP Quinases , Magnetoterapia/métodos , Camundongos , Modelos Biológicos , Células-Tronco Neoplásicas/metabolismo
19.
Rev. costarric. cardiol ; 20(supl.1): 19-21, oct. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-978341

RESUMO

Resumen Se presenta el caso de una paciente portadora de una miocardiopatía dilatada y marcapasos epicárdico unicameral im plantado por bloqueo atrioventricular completo, quien respondió favorablemente a la terapia de resincronización cardia ca; durante el seguimiento, requirió el implante de un nuevo electrodo del ventrículo izquierdo, el cual fue implantado a través de una vena posterior.


Abstract Dysautonomia and Chagas disease We present the case of a patient with a congenital dilated myocardiopathy and a single-chamber epicardic pacemaker, implanted by a complete atrioventricular block, who had a favorable response to cardiac resinchronisation therapy; during follow-up, she required a new left ventricle electrode which was implanted through a left posterior vein.


Assuntos
Humanos , Feminino , Adulto , Cardiomiopatia Dilatada , Costa Rica , Eletrodos , Bloqueio Atrioventricular , Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca
20.
Rev. costarric. cardiol ; 20(supl.1): 26-31, oct. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-978343

RESUMO

Resumen La terapia de ablación con catéter de arritmias cardiacas ha revolucionado el manejo de estos padecimientos en las úl timas décadas. La fibrilación atrial, que es una de las arritmias más frecuentes también ha sido susceptible a este tipo de abordaje. La complejidad de sus mecanismos y diferentes formas de manifestación ha hecho que las técnicas para realizar la ablación hayan requerido de un perfeccionamiento progresivo. También la selección de los pacientes que ten drán mayor beneficio del procedimiento lo tenemos más claro hoy en día. En el presente artículo se hace una revisión de estos aspectos y los resultados de los últimos estudios que sustentan las guías actuales para su manejo con esta forma de tratamiento.


Abstract Clinical application of catheter ablation for the treatment of Atrial Fibrillation Cardiac catheter ablation therapy has revolutionized the management of these conditions in the latest decades. Atrial fibrillation, which is one of the most frequent arrhythmias, has also been susceptible to this type of approach. The complexity of its mechanisms and different forms of manifestation has made the techniques to perform the ablation necessary for a progressive improvement. Also the selection of the patients that will have greater benefit of the procedure it is clearer nowadays. In this article we present a review of these aspects and the results of the latest studies that support the current guidelines for their management with this form of treatment.


Assuntos
Humanos , Arritmias Cardíacas , Fibrilação Atrial , Ablação por Cateter , Costa Rica , Criocirurgia
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