Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
1.
Pediatr Pulmonol ; 58(10): 2930-2940, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37565706

RESUMEN

BACKGROUND: Multisystem inflammatory syndrome in children (MISC) is a phenomenon that appeared in children infected with or exposed to severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). The typical onset of MISC is 4-6 weeks following SARS-CoV-2 infection and is formulated to be due to an immune response. METHODS: Our study retrospectively analyzed data from a tertiary center in United Arab Emirates of MISC patients who were admitted to either general pediatric wards or pediatric intensive care (PICU) or who came exclusively for follow-up (post-PICU admission) from May 2020 to August 2021. RESULTS: The total sample size was 50 patients, and the study included a comparison of MISC-PICU admissions with MISC-non-PICU admissions. The MISC-PICU sample size was 18 patients, 50% females, with mean age of 8.3 years all were previously healthy. MISC-PICU patients had deranged blood counts with a lower hemoglobin count, a more pronounced lymphopenia and thrombocytopenia along with hypoalbuminemia. MISC-PICU patients presented with relatively higher inflammatory markers: C-reactive protein, procalcitonin, ferritin, and d-dimer. Immunological studies were significantly higher for interleukin-6 levels in PICU patients. On echocardiography, higher myocardial dysfunction was more notable in MISC-PICU patients. Likewise, MISC-PICU patients were provided with more extensive therapy. As part of our study course, we reevaluated our MISC-PICU patients twice, once at 48 h post-PICU admission and again 4-6 weeks after discharge from the hospital. No deaths have been recorded in the cohort. CONCLUSION: This study evaluated risk factors of MISC and potential severity features. Follow-up of patients on discharge showed improvement across all domains.

2.
Environ Pollut ; 336: 122475, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37652229

RESUMEN

Particle matter (PM) is a complex mixture of particles suspended in the air, mainly caused by fuel combustion from vehicles and industry, and has been related to pulmonary and cardiovascular diseases. The Metropolitan Area of Aburrá Valley in Colombia is the second most populous urban agglomeration in the country and the third densest in the world, composed of ten municipalities. Examining the physicochemical properties of PM is crucial in comprehending its composition and its effects on human health, as it varies based on the socioeconomic dynamics specific to each city. This study characterized the PM collected from the north, south, and central zones to evaluate its chemical composition and morphology. Different elements such as silicon, carbon, aluminum, potassium, calcium, sodium, iron, magnesium, and copper and the presence of unburned fuel, motor oil, and silicon fibers were identified. In vitro and in silico studies were conducted to evaluate the toxicity of the PM, and it was found that the PM collected from the central zone had the greatest impact on cell viability and caused DNA damage. The in silico study demonstrated that PM has concentration-dependent proarrhythmic effects, reflected in an action potential duration shortening and an increased number of reentries, which may contribute to the development of cardiac arrhythmias. Overall, the results suggest that the size and chemical composition of ambient PM can induce toxicity and play an important role in the generation of arrhythmias.

3.
Pharmaceuticals (Basel) ; 16(2)2023 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-37259421

RESUMEN

Colorectal cancer mortality rate and highly altered proteins from the Wnt/ß-catenin pathway increase the scientific community's interest in finding alternatives for prevention and treatment. This study aims to determine the biological effect of chlorogenic acid (CGA) on two colorectal cancer cell lines, HT-29 and SW480, and its interactions with ß-catenin and LRP6 to elucidate a possible modulatory mechanism on the Wnt/ß-catenin pathway. These effects were determined by propidium iodide and DiOC6 for mitochondrial membrane permeability, MitoTracker Red for mitochondrial ROS production, DNA content for cell distribution on cell cycle phases, and molecular docking for protein-ligand interactions and binding affinity. Here, it was found that CGA at 2000 µM significantly affects cell viability and causes DNA fragmentation in SW480 cells rather than in HT-29 cells, but in both cell lines, it induces ROS production. Additionally, CGA has similar affinity and interactions for LRP6 as niclosamide but has a higher affinity for both ß-catenin sites than C2 and iCRT14. These results suggest a possible modulatory role of CGA over the Wnt/ß-catenin pathway in colorectal cancer.

4.
Nutrients ; 14(22)2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36432565

RESUMEN

The Wnt/ß-Catenin pathway alterations present in colorectal cancer (CRC) are of special interest in the development of new therapeutic strategies to impact carcinogenesis and the progression of CRC. In this context, different polyphenols present in natural products have been reported to have modulatory effects against the Wnt pathway in CRC. In this study, we evaluate the effect of two polyphenol-rich coffee extracts and chlorogenic acid (CGA) against SW480 and HT-29 CRC cells. This involved the use of MTT and SRB techniques for cell viability; wound healing and invasion assay for the evaluation of the migration and invasion process; T cell factor (TCF) reporter plasmid for the evaluation of transciption factor (TCF) transcriptional activity; polymerase chain reaction (PCR) of target genes and confocal fluorescence microscopy for ß-Catenin and E-Cadherin protein fluorescence levels; and subcellular localization. Our results showed a potential modulatory effect of the Wnt pathway on CRC cells, and we observed a reduction in the transcriptional activity of ß-catenin. All the results were prominent in SW480 cells, where the Wnt pathway deregulation has more relevance and implies a constitutive activation of the signaling pathway. These results establish a starting point for the discovery of a mechanism of action associated with these effects and corroborate the anticancer potential of polyphenols present in coffee, which could be explored as chemopreventive molecules or as adjunctive therapy in CRC.


Asunto(s)
Neoplasias Colorrectales , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Vía de Señalización Wnt , Ácido Clorogénico/farmacología , Ácido Clorogénico/uso terapéutico , Polifenoles/farmacología , Polifenoles/uso terapéutico , Neoplasias Colorrectales/metabolismo
5.
Heliyon ; 8(6): e09519, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35669542

RESUMEN

Cancer is one of the leading causes of death in the world. Chemotherapy is presented as an option for treatment of this disease, however, low specificity, high resistance rates, toxicity and hypersensitivity reactions, make it necessary to search for therapeutic alternatives that increase the selectivity of treatment, reduce the side effects and enhance its antitumor potential. Natural products are accessible, inexpensive and less toxic sources; in addition, they have multiple mechanisms of action that can potentiate the outcome of chemotherapeutics. In this review, we present evidence on the beneficial effect of the interaction of dietary phytochemicals with chemotherapeutical agents for cancer treatment. This effect is generated by different mechanisms of action such as, increased tumoricidal effect via sensitization of cancer cells, reversing chemoresistance through inhibition of several targets involved in the development of drug resistance and, decreasing chemotherapy-induced toxicity in non-tumoral cells by the promotion of repair mechanisms. Studies discussed in this review will provide a solid basis for the exploration of the potential use of natural products in combination with chemotherapeutical agents, to overcome some of the difficulties that arise in the management of cancer patients.

6.
Int J Surg Case Rep ; 94: 107095, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35461184

RESUMEN

BACKGROUND: Gastroschisis is a closure defect of the abdominal wall classified as complex when it presents with necrosis, volvulus, or atresia of the gastrointestinal tract. Jejunoileal atresia is caused by abnormal closure, discontinuity, or narrowing of the intestine. Apple Peel or type IIIb is the rarest presentation, with an incidence of 1.3 per 10,000 live births. In addition to presenting a high mortality rate. PRESENTATION OF CASE: We present a preterm newborn patient of 30 weeks with a diagnosis of gastroschisis and jejunoileal atresia type IIIB. The congenital wall defect was closed in the first surgical stage, and he was then taken at four weeks to correct the atresia. In the second surgery, we found a difference in intestinal calibers of 8:1, and the surgical team decides to perform remodeling of the proximal sac with a mechanical stapler and perform anastomosis using the Santulli technique. On day 6 of life, enteral feeding began through a nutrition tube localized under intestinal anastomosis with progressive nutritional increase. Subsequently, intermittent and progressive occlusion of the stoma was performed, leading the patient to a definitive surgical closure one month later. CONCLUSIONS: The mortality rate for gastroschisis and complex intestinal atresia is high. Advances in prenatal diagnosis, neonatal intensive care, and proper surgical correction are crucial to improving survival rates. The Santulli procedure is a surgical alternative for intestinal atresias with a caliber discrepancy greater than 4 to 1 or when the characteristics of the distal part do not allow a primary anastomosis to be performed.

7.
Case Rep Pediatr ; 2022: 3373289, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35127192

RESUMEN

Multisystem inflammatory syndrome in children (MIS-C) after COVID-19 has been recognized as a complication arising due to cytokine storm. Several management strategies including intravenous immunoglobulin and immunomodulators have been reported. This case report highlights the use of a cytokine filter (oXiris®) in the management of MIS-C. Cytokine filters eliminate cytokines and reduce the demand for vasopressors in patients with other inflammatory conditions. A 7-year-old child with prolonged fever, vomiting, hypotension, elevated inflammatory mediators, and dilatation of coronary arteries on echocardiography was found to have positive SARS-CoV-2 IgG and PCR. He was diagnosed as MIS-C and was managed in the pediatric intensive care unit. He required ventilatory support, vasopressors, and continuous renal replacement therapy (CRRT) with a cytokine filter. He showed marked improvement within 24 hours of initiating CRRT. Cytokine filters may have a potential role in the management of severely ill children due to MIS-C. To our knowledge, this is the first report of successful use of the oXiris® membrane in MIS-C. However, further case series and controlled trials are needed to establish its use in this condition.

8.
Heliyon ; 7(8): e07738, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34458602

RESUMEN

Noncommunicable diseases, the leading cause of mortality around the world, are responsible for approximately 75% of premature adult deaths (ages 30-69). To tackle this issue, a healthy diet based on functional foods, including cocoa and its derivatives, has been increasingly promoted. The polyphenols present in cocoa have been of interest due to their antioxidant potential and their possible protective role in the context of noncommunicable diseases, such as diabetes and cardiovascular conditions. However, during cocoa postharvest and industrialization, the concentration of these bioactive compounds is reduced, possibly affecting their health-promoting properties. Therefore, this paper reviews in the literature in this field to find the total polyphenol content in cocoa during the postharvest and industrialization processes in order to define concentration ranges as a reference point for future research. In addition, it discusses in vitro and in vivo studies into the biological antioxidant potential of cocoa and its derivatives. This review covers publications in indexed databases from 2010 to 2020, their data were processed and presented here using box plots. As a result, we identified the concentration ranges of polyphenols depending on the type of matrix, treatment and country, as well as their relationship with the main bioactive compounds present in cocoa that are associated with their possible antioxidant biological potential and health-related benefits.

9.
Pharmaceuticals (Basel) ; 14(8)2021 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-34451858

RESUMEN

Colorectal cancer is one of the leading death-related diseases worldwide, usually induced by a multifactorial and complex process, including genetic and epigenetic abnormalities and the impact of diet and lifestyle. In the present study, we evaluated the biological impact of two of the main coffee polyphenols, chlorogenic acid (CGA) and caffeic acid (CA), as well as two polyphenol-rich coffee extracts (green coffee extract and toasted coffee Extract) against SW480 and SW620 colorectal cancer cells. First, the total phenolic content and the antioxidant capability of the extracts were determined. Then, cytotoxicity was evaluated by MTT and SBR. Finally, a wound healing assay was performed to determine the impact on the cell migration process. The results showed a cytotoxic effect of all treatments in a time and dose-dependent manner, which decreased the viability in both cell lines at 24 h and 48 h; likewise, the migration capability of cells decreased with low doses of treatments. These results suggest the potential of coffee to modulate biological mechanisms involved in colorectal cancer development; however, more studies are required to understand the mechanistic insights of these observations.

10.
Rev. colomb. cir ; 35(4): 553-557, 2020.
Artículo en Español | LILACS | ID: biblio-1147895

RESUMEN

Introducción. La pandemia por COVID-19 ha ocasionado cambios de todo orden en el mundo. Las medidas de emergencia han impactado de manera negativa la oportunidad en la prestación de los servicios de salud y los procesos de educación médica. Los educadores se han visto obligados a innovar y apoyarse mucho más en las tecnologías de la información y la comunicación, con el fin de lograr los objetivos de formación. Objetivo. Describir la implementación de estrategias de enseñanza para hacer frente a los retos que impone la pandemia por COVID-19 en un programa de formación en cirugía pediátrica. Métodos. Revisión de los registros y la asistencia a las actividades académicas programadas antes y después de la llegada del coronavirus a Colombia. Resultados. Como respuesta a la contingencia, y con el apoyo de las tecnologías de la información y la comunicación, se incrementó el número de actividades académicas en un 100 %, se logró duplicar la asistencia a las mismas y la participación de expertos nacionales e internacionales. Conclusión. La nueva normalidad impuesta por la pandemia por COVID-19 exige a los educadores en salud desarrollar estrategias de enseñanza y aprendizaje innovadoras las cuales, con la integración de las tecnologías disponibles, permiten enfrentar las dificultades y cumplir con los objetivos de formación en salud


Introduction. The COVID-19 pandemic has caused changes of all kinds in the world. The emergency measures have negatively affected the opportunity in the provision of health services and the medical education processes. Educators have been forced to innovate and have supported much more on information and communication technologies, in order to achieve the training objectives. Objective. To describe the implementation of teaching strategies to face the challenges posed by the COVID-19 pandemic in a pediatric surgery training program. Methods. Review of records and attendance at scheduled academic activities before and after the arrival of the coronavirus in Colombia. Results. In response to the contingency, and with the support of information and communication technologies, the number of academic activities was increased by 100%, attendance at them was doubled and the participation of national and international experts. Conclusion. The new normal imposed by the COVID-19 pandemic requires health educators to develop inno-vative teaching and learning strategies, which, with the integration of available technologies, make it possible to face difficulties and meet health-training objectives


Asunto(s)
Humanos , Infecciones por Coronavirus , Telemedicina , Educación Médica , Proyectos de Tecnologías de Información y Comunicación
11.
Rev. colomb. gastroenterol ; 34(2): 125-134, abr.-jun. 2019. tab, graf
Artículo en Español | LILACS | ID: biblio-1013928

RESUMEN

Resumen Antecedentes: la cirugía transanal endoscópica es un abordaje mínimamente invasivo recientemente descrito, que provee una exposición superior y permite el acceso a las lesiones del recto en toda su extensión. Además, provee un riesgo menor de compromiso de los márgenes de resección, menores tasas de recurrencia y una menor morbimortalidad en comparación con la escisión transanal convencional o las remociones endoscópicas. Objetivos: se pretende describir la experiencia inicial y los resultados con la cirugía transanal mínimamente invasiva (transanal minimally invasive surgery, TAMIS) en términos de resecciones completas y posibles complicaciones relacionadas con el procedimiento. Materiales y métodos: esta una serie de casos con un seguimiento prospectivo de los pacientes con TAMIS. Se analizaron los resultados de 27 pacientes intervenidos en varios centros de Medellín, Colombia, entre enero de 2012 y diciembre de 2016, realizados con cirugía laparoscópica monopuerto (single-port laparoscopic surgery, SILS) (21 casos) o el GelPOINT® Path (6 casos), junto con el apoyo de la óptica del laparoscopio (16 pacientes) y del endoscopio flexible (11 pacientes). Resultados: se realizaron 27 TAMIS en el mismo número de pacientes, 10 mujeres (37 %) y 17 hombres fueron evaluados. Se realizó un seguimiento a los pacientes durante aproximadamente 12 meses, en promedio 32 meses. La edad promedio fue de 68 años (52-83 años). El tamaño promedio del tumor fue de 5,3 cm (2-9 cm) y la distancia promedio desde el margen anal fue de 7 cm (5-9 cm) Las complicaciones posoperatorias se dieron en 6 casos (22 %) Una perforación rectal se corrigió por vía laparoscópica en el mismo acto quirúrgico y otra por la misma vía transanal. Una estenosis rectal se manejó con dilatación digital, y hubo un caso de sangrado rectal menor, uno de retención urinaria y un paciente presentó un cáncer rectal avanzado a los tres meses de la resección con margen microscópico positivo (4 %). No hubo reingresos. La mortalidad por la intervención fue nula. La patología operatoria reportó la presencia de adenoma de bajo grado en 3 casos (11 %), de alto grado en 11 (41 %), adenocarcinoma in situ en 6 (22 %), tumor neuroendocrino en 5 pacientes (18 %), 1 caso de fibrosis cicatricial (4 %) y 1 de leiomioma (4 %). Limitaciones: los resultados no son extrapolables a la población general debido al poco número de intervenciones y la ejecución limitada a solo dos autores. Conclusiones: en nuestra experiencia inicial, TAMIS es un procedimiento mínimamente invasivo con una baja morbilidad posoperatoria, es curativa para lesiones benignas y para pacientes seleccionados con cáncer temprano.


Abstract Background: Transanal endoscopic surgery, a recently described minimally invasive approach, provides superior exposure and access to the entirety of rectal lesions and has lower risks of compromising resection margins, lower recurrence rates and lower morbidity and mortality than do conventional transanal excision and endoscopic removals. Objectives: The aim of this study is to describe our initial experience and with minimally invasive transanal surgery (TAMIS) and its results in terms of complete resections and complications possibly related to the procedure. Materials and methods: This is a series of TAMIS cases with prospective follow-ups. We analyzed the results of 27 patients who underwent the procedure at several centers in Medellín, Colombia, between January 2012 and December 2016. Twenty patients had Single Incision Laparoscopic Surgery while the GelPOINT path transanal access platform was used for the other six patients. Laparoscope optics provide support for 16 procedures while the more recently introduced flexible endoscope supported eleven procedures. Results: Twenty-seven TAMIS procedures were performed and evaluated. Ten patients were women (37%), and 17 were men. On average, patients were followed up for 32 months, but none less than 12 months. Average patient age was 68 years (52 to 83 years). The average tumor size was 5.3 cm (2 to 9 cm) and the average distance from the anal margin was 7 cm (5 to 9 cm). Postoperative complications occurred in six cases (22%). In one case, a rectal perforation was corrected laparoscopically during the procedure. Another perforation was corrected by the same transanal route. A rectal stenosis was managed with digital dilatation, there was one case of minor rectal bleeding, one case of urinary retention and one patient developed advanced rectal cancer with a positive microscopic margin (4%) three months after resection. There were no readmissions. There were no deaths due to the intervention. Pathology reported low grade adenomas in three cases (11%), high grade adenomas in 11 cases (41%), in-situ adenocarcinoma in six cases (22%), neuroendocrine tumors in five cases (19%), and one case each of cicatricial fibrosis (4%) and leiomyoma (4%). Limitations: The results cannot be extrapolated to the general population because of the limited number of interventions and performance of procedures by only two authors. Conclusions: Our initial experience shows TAMIS to be a minimally invasive procedure with low postoperative morbidity which is curative for benign lesions and for selected patients with early cancer.


Asunto(s)
Humanos , Masculino , Femenino , Cirugía Endoscópica Transanal , Neoplasias del Recto , Recurrencia , Fibrosis , Adenocarcinoma , Mortalidad , Adenocarcinoma in Situ , Leiomioma
12.
Front Pediatr ; 7: 542, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31998671

RESUMEN

We are reporting a case of pyrethroid poisoning with atypical presentation in a 21-month-old toddler who was transferred to us from a peripheral center. Signs and symptoms at presentation were predominantly of cardiopulmonary dysfunction contrary to more common presenting features of gastrointestinal and neurological impairment. The reason for this seems to be the aspiration pneumonitis as a consequence of vomiting induced by parents at home, rather than the toxin itself even though a rather rapid progression of lung injury does not rule out the possibility. He had developed decreased level of consciousness and increased work of breathing after ingestion, which had progressed to Acute Respiratory Distress Syndrome, septic shock, and multi organ failure. He even had a brief cardiac arrest with Return of Spontaneous Circulation after 5 min of cardiopulmonary resuscitation, immediately after arrival at our unit, which seemed more likely to be a consequence of inappropriate management during transfer of the child. In addition to antibiotics and vasopressors, he required high frequency oscillatory ventilation and prone positioning initially, and lung-protective conventional ventilation later. His cardiopulmonary status improved gradually and he was successfully extubated after 12 days. Other organ systems also showed complete recovery. Even though Magnetic Resonance Imaging of brain done a few days after cardiac arrest showed features suggestive of hypoxic-ischemic encephalopathy he showed complete neurological recovery. He was thriving well at three-month follow-up with no neurological deficits, good exercise tolerance, and normal renal and liver function. Atypical presentation of pyrethroid poisoning is associated with significant morbidities and there seems to no reliable parameters in children to identify the risk of the same. Considering that there is no specific antidote, prompt, and aggressive supportive therapy is necessary for a favorable outcome. This case highlights several important aspects in the care of the pediatric patient after ingestion of insecticides. First, attempt to induce emesis, especially outside of a healthcare facility is not only ineffective but also highly dangerous, and should not be done. Second, unstable patients require inter and intrahospital transfer by experienced and trained personnel; and lastly, management for these complex and atypical cases should be done as early as possible in a center which is equipped to provide high level of circulatory and ventilatory support while prioritizing neuro-protective measures, and neurologic recovery and rehabilitation.

13.
Ann Hepatol ; 17(3): 444-460, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29735783

RESUMEN

INTRODUCTION AND AIM: Epigenetic alterations play an essential role in cancer onset and progression, thus studies of drugs targeting the epigenetic machinery are a principal concern for cancer treatment. Here, we evaluated the potential of the combination of the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (5aza-dC) and the pan-deacetylase inhibitor Trichostatin A (TSA), at low cytotoxic concentrations, to modulate the canonical Wnt/ß-catenin pathway in liver cancer cells. MATERIAL AND METHODS: Pyrosequencing was used for DNA methylation analyses of LINE-1 sequences and the Wnt/ß-catenin pathway antagonist DKK3, SFRP1, WIF1 and CDH1. qRT-PCR was employed to verify the expression of the antagonist. Pathway regulation were evaluated looking at the expression of ß-catenin and E-cadherin by confocal microscopy and the antitumoral effects of the drugs was studied by wound healing and clonogenic assays. RESULTS: Our result suggest that 5aza-dC and TSA treatments were enough to induce a significant expression of the pathway antagonists, decrease of ß-catenin protein levels, re-localization of the protein to the plasma membrane, and pathway transcriptional activity reduction. These important effects exerted an antitumoral outcome shown by the reduction of the migration and clonogenic capabilities of the cells. CONCLUSION: We were able to demonstrate Wnt/ ß-catenin pathway modulation through E-cadherin up-regulation induced by 5aza-dC and TSA treatments, under an activation-pathway background, like CTNNB1 and TP53 mutations. These findings provide evidences of the potential effect of epigenetic modifier drugs for liver cancer treatment. However, further research needs to be conducted, to determine the in vivo potential of this treatment regimen for the management of liver cancer.


Asunto(s)
Antígenos CD/metabolismo , Antimetabolitos Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Cadherinas/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Metilación de ADN/efectos de los fármacos , Decitabina/farmacología , Epigénesis Genética/efectos de los fármacos , Ácidos Hidroxámicos/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Antígenos CD/genética , Cadherinas/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Proliferación Celular/genética , Metilasas de Modificación del ADN/antagonistas & inhibidores , Metilasas de Modificación del ADN/metabolismo , Inhibidores Enzimáticos/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Mutación , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba , Vía de Señalización Wnt/efectos de los fármacos , Vía de Señalización Wnt/genética , beta Catenina/genética , beta Catenina/metabolismo
14.
RSC Adv ; 8(22): 12017-12028, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30761211

RESUMEN

An accurate and efficient characterization of the polyelectrolyte properties for cytoskeleton filaments are key to the molecular understanding of electrical signal propagation, bundle and network formation, as well as their potential nanotechnological applications. In this article, we introduce an innovative multi-scale approach able to account for the atomistic details of a protein molecular structure, its biological environment, and their impact on electrical impulses propagating along wild type Actin filaments. The formulation includes non trivial contributions to the ionic electrical conductivity and capacitance coming from the diffuse part of the electrical double layer of G-actins. We utilize this monomer characterization in a nonlinear inhomogeneous transmission line prototype model to account for the monomer-monomer interactions, dissipation and damping perturbations along the filament length. A novel, simple, accurate, approximate analytic expression has been obtained for the transmission line model. Our results reveal the propagation of electrical signal impulses in the form of solitons for the range of voltage stimulus and electrolyte solutions typically present for intracellular and in-vitro conditions. The approach predicts a lower electrical conductivity with higher linear capacitance and nonlinear accumulation of charge for intracellular conditions. Our results show a significant influence of the voltage input on the electrical impulse shape, attenuation and kern propagation velocity. The filament is able to sustain the soliton propagation at almost constant kern velocity for the in-vitro condition, whereas the intracellular condition displays a remarkable deceleration. Additionally, the solitons are narrower and travel faster at higher voltage input. As a unique feature, this multi-scale theory is able to account for molecular structure conformation (mutation) and biological environment (protonations/deprotonations) changes often present in pathological conditions. It is also applicable to other highly charged rod-like polyelectrolytes with relevance in biomedicine and biophysics.

15.
Comput Methods Programs Biomed ; 145: 23-33, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28552123

RESUMEN

BACKGROUND AND OBJECTIVES: Cell imaging is a widely-employed technique to analyze multiple biological processes. Therefore, simple, accurate and quantitative tools are needed to understand cellular events. For this purpose, Bio-EdIP was developed as a user-friendly tool to quantify confluence levels using cell culture images. METHODS: The proposed algorithm combines a pre-processing step with subsequent stages that involve local processing techniques and a morphological reconstruction-based segmentation algorithm. Segmentation performance was assessed in three constructed image sets, comparing F-measure scores and AUC values (ROC analysis) for Bio-EdIP, its previous version and TScratch. Furthermore, segmentation results were compared with published algorithms using eight public benchmarks. RESULTS: Bio-EdIP automatically segmented cell-free regions from images of in vitro cell culture. Based on mean F-measure scores and ROC analysis, Bio-EdIP conserved a high performance regardless of image characteristics of the constructed dataset, when compared with its previous version and TScratch. Although acquisition quality of the public dataset affected Bio-EdIP segmentation, performance was better in two out of eight public sets. CONCLUSIONS: Bio-EdIP is a user-friendly interface, which is useful for the automatic analysis of confluence levels and cell growth processes using in vitro cell culture images. Here, we also presented new manually annotated data for algorithms evaluation.


Asunto(s)
Técnicas de Cultivo de Célula/instrumentación , Procesamiento de Imagen Asistido por Computador , Algoritmos , Células Hep G2 , Humanos , Curva ROC , Programas Informáticos
16.
Entramado ; 12(1)jun. 2016.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1534346

RESUMEN

La Alianza del Pacífico se define como una iniciativa de integración profunda que procura abordar temas complejos (no de índole exclusivamente comercial) y que se fundamenta en las motivaciones y aspiraciones de los países miembros y fundadores, que tienen como objetivo lograr: una eficiente apertura comercial, la incursión a nuevos mercados y la inserción en las Cadenas Globales de Valor (GCV). A pesar de que entre Colombia y cada uno de los países que hoy conforman la Alianza del Pacífico existen acuerdos y tratados comerciales de décadas atrás, una revisión de la dinámica comercial entre el país cafetero y este grupo evidencia: por una parte, el deterioro en el volumen de las exportaciones, y por otra, un aumento de las importaciones, principalmente con México, lo que ha generado una balanza comercial en déficit, y un rezago considerable de apertura comercial, medida en términos per cápita. No obstante, al profundizar en el análisis por medio de la aplicación de indicadores como el de Balassa, se determina una cierta estabilidad y eficiencia de Colombia al exportar hacia estos países, como también la existencia de un grupo de productos con una considerable ventaja comparativa, pero poco exportados por el país cafetero.


The Pacific Alliance is an initiative characterized by deeper integration that seeks to address complex issues (not those related exclusively to trade). The PA is founded on the motivations and aspirations of its founder countries. The PA aims to achieve efficient trade liberalization, entry into new markets and integration into Global Value Chains (GVC). Although the existing trade agreements between Colombia and each of the member countries date from several decades ago, a current review of trade dynamics between Colombia and all the other member countries highlights, on the one hand, the deterioration in the volume of exports, and on the other hand, an increase in imports, mainly from Mexico. This has generated a negative trade balance and a considerable lag in terms of openness to foreign trade, measured in per capita terms. However an in-depth analysis through the application of indicators such as Balassa, shows Colombia possesses a measure of stability and efficiency to export to these countries, as well as highlighting the existence of a group of products with considerable comparative advantage, but barely exported by Colombia.


A Aliança do Pacífico é definida como uma iniciativa de integração profunda que procura abordar questões complexas (natureza não puramente comercial) e baseia-se nas motivações e aspirações dos países membros e fundadores, que visam alcançar: uma liberalização do comércio eficiente a incursão em novos mercados e integração nas Cadeias Globais de Valor (GCV). Embora entre a Colômbia e cada um dos países que hoje compõem a Aliança do Pacífico, existem acordos comerciais e tratados de décadas atrás, uma revisão da dinâmica das trocas comerciais entre o país de café e este grupo evidência: por um lado, a deterioração o volume de exportações, e, por outro, o aumento das importações, principalmente do México, o que gerou um déficit da balança comercial e um atraso considerável de liberalização do comércio, medido em termos per capita. No entanto, uma análise mais aprofundada através da aplicação de indicadores, tais como Balassa, determina-se uma certa estabilidade e eficiência da Colômbia para exportar para esses países, bem como a existência de um grupo de produtos com considerável vantagem comparativa, mas pouco café exportado pelo país.

17.
Artículo en Inglés | MEDLINE | ID: mdl-26714991

RESUMEN

BACKGROUND: Literature on the use of nicardipine, a dihydropyridine calcium channel antagonist, in children recovering from cardiac surgery is sparse and, to our knowledge, nonexistent in children with single ventricle anatomy. We aimed to report our experience with nicardipine in these patient populations. METHODS: We performed a retrospective review of children recovering from aortic coarctectomy or superior cavopulmonary anastomoses who received nicardipine for hypertension at our institution between 2007 and 2013. Hemodynamic variables prior to and after nicardipine initiation were compared using paired t tests. RESULTS: Seven children recovering from aortic coarctectomy (median age 8.6 months, range: 1.5 months-7.9 years) and four children recovering from superior cavopulmonary anastomosis (median age: seven months, range: five-nine months) were reviewed. For all patients, at six hours after initiation of nicardipine, mean systolic blood pressure was significantly decreased, 123 ± 19 versus 103 ± 14 mm Hg (P = .001), as were diastolic blood pressure, 68 ± 20 versus 53.5 ± 10 mm Hg (P = .041), and sodium nitroprusside dose, 4.3 ± 2.9 versus 1.3 ± 1.7 mcg/kg/min (P = .002). Further, within 24 hours, serum lactate decreased from 1.45 ± 0.82 to 0.81 ± 0.29 mg/dL (P = .016). Heart rate, blood urea nitrogen, and serum creatinine measurements were statistically unchanged. CONCLUSIONS: Nicardipine effectively decreased blood pressure without apparent adverse events in a small cohort of children with postoperative hypertension while recovering from aortic coarctectomy or superior cavopulmonary anastomosis. Further research comparing nicardipine to more conventional titratable antihypertensive agents in these patient populations is warranted.


Asunto(s)
Coartación Aórtica/cirugía , Presión Sanguínea/efectos de los fármacos , Puente Cardíaco Derecho/efectos adversos , Hipertensión/tratamiento farmacológico , Nicardipino/administración & dosificación , Complicaciones Posoperatorias , Bloqueadores de los Canales de Calcio/administración & dosificación , Niño , Preescolar , Femenino , Humanos , Hipertensión/etiología , Hipertensión/fisiopatología , Lactante , Infusiones Intravenosas , Masculino , Estudios Retrospectivos
18.
Ann Hepatol ; 14(1): 64-74, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25536643

RESUMEN

BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) is the most common primary liver cancer diagnosed worldwide. Deregulation of Wnt/beta-catenin pathway has been associated with the development of HCC in a substantial number of cases in Europe and far less in Asia. Nothing is known about this pathway in HCC cases from South America. This study aimed to investigate the frequency of mutations in beta-catenin gene (CTNNB1) and the subcellular localization of beta-catenin in HCC cases from Colombia. MATERIAL AND METHODS: We determine by direct sequencing the frequency of mutations in exon 3 of CTNNB1 gene and by immunohistochemistry the subcellular localization of beta-catenin in 54 samples of HCC obtained from three pathology units in Bogota and Medellin cities. RESULTS: Only three HCC cases (5.6%) were found mutated at residues (G34E, S45P, P44S, T41I) important for phosphorylation and ubiquitination of beta-catenin protein. Strikingly, nuclear or cytoplasmic accumulation of beta-catenin, hallmark of Wnt pathway activation, was found in 42.6% HCC cases (23/54). Interestingly, beta-catenin accumulation was significantly more frequent in young patients and hepatitis B virus-related HCC. CONCLUSIONS: Although, CTNNB1 exon 3 mutations are not frequent in HCC from Colombian patients, our findings indicate that Wnt/beta-catenin signaling is activated in 42.6% of HCC samples. Furthermore, Wnt signaling was demonstrated in HCC cases associated of HBV infection, one of the most important HCC risk factors in Colombia.


Asunto(s)
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Mutación , Vía de Señalización Wnt/genética , beta Catenina/genética , Factores de Edad , Anciano , Anciano de 80 o más Años , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/patología , Estudios de Cohortes , Colombia , Exones , Femenino , Hepatitis B Crónica/complicaciones , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estudios Retrospectivos , beta Catenina/metabolismo
19.
Hepat Res Treat ; 2011: 582945, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22114738

RESUMEN

Hepatocellular Carcinoma (HCC) is a leading cause of cancer-related death worldwide. Globally, the most important HCC risk factors are Hepatitis B Virus (HBV) and/or Hepatitis C Virus (HCV), chronic alcoholism, and dietary exposure to aflatoxins. We have described the epidemiological pattern of 202 HCC samples obtained from Colombian patients. Additionally we investigated HBV/HCV infections and TP53 mutations in 49 of these HCC cases. HBV biomarkers were detected in 58.1% of the cases; HBV genotypes F and D were characterized in three of the samples. The HCV biomarker was detected in 37% of the samples while HBV/HCV coinfection was found in 19.2%. Among TP53 mutations, 10.5% occur at the common aflatoxin mutation hotspot, codon 249. No data regarding chronic alcoholism was available from the cases. In conclusion, in this first study of HCC and biomarkers in a Colombian population, the main HCC risk factor was HBV infection.

20.
Rev. peru. biol. (Impr.) ; 17(1): 133-136, abr. 2010. ilus, tab
Artículo en Español | LIPECS | ID: biblio-1111329

RESUMEN

En el presente trabajo describimos el aislamiento y la actividad de biodegradación de microorganismos sobre polietileno de baja densidad. Los microorganismos fueron aislados de materiales plásticos con evidencias de deterioro procedentes de un relleno sanitario de Lima. Las muestras fueron filtradas y preseleccionadas en medio de sales minerales a pH 5,5 y 7, para hongos y bacterias respectivamente. Se aislaron 6 cepas, identificadas como Pseudomonas sp. MP3a y MP3b, Penicillium sp. MP3a, Rhodotorula sp. MP3b, Hyalodendron sp. MP3cy una levadura no identificada. La acción degradativa del consorcio microbiano aislado fue evidenciada porvariaciones en el espectro infrarrojo del polietileno con respecto al polímero sin tratamiento, observándose la reducción del índice de carbonilo (83,89% a pH 7 y 4,08% a pH 5,5) y de terminaciones con dobles enlaces (19,77% a pH 7 y 6,47% a pH 5,5). Finalmente se determinó el porcentaje de peso perdido por el polietileno sometido a las cepas aisladas, observándose una disminución de 5,4% a pH 7 y 4,8% a pH5,5.


In this paper, we describe the isolation and biodegradation activity of microorganisms on low density polyethylene. The microorganisms were collected from plastic materials with evidence of deterioration from a landfill. The samples were filtered and selected in a mineral salts medium at pH 5.5 and 7 for bacteria and fungi respectively. Six strains were isolated, identified as Pseudomonas sp. Hyalodendron sp., Penicillium sp. and Rhodotorula sp.Microbial activity was evidenced by changes in the infrared spectrum of polyethylene with respect to the polymer without treatment. Reduction of carbonyl index (83.89% at pH 7 and 4.08% at pH 5.5) and double bonds index (19.77% at pH 7 and 6.47% at pH 5.5) were observed. Finally we determined the percentage of weight lost by the polyethylene subjected to activity of the strains, with a decrease of 5.4% at pH 7 and 4.8% at pH5, 5.


Asunto(s)
Rellenos Sanitarios , Biodegradación Ambiental , Consorcios Microbianos , Polietileno
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...