Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 70
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Neurobiol Dis ; 195: 106491, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38575092

RESUMEN

Focal cortical dysplasia (FCD) represents a group of diverse localized cortical lesions that are highly epileptogenic and occur due to abnormal brain development caused by genetic mutations, involving the mammalian target of rapamycin (mTOR). These somatic mutations lead to mosaicism in the affected brain, posing challenges to unravel the direct and indirect functional consequences of these mutations. To comprehensively characterize the impact of mTOR mutations on the brain, we employed here a multimodal approach in a preclinical mouse model of FCD type II (Rheb), focusing on spatial omics techniques to define the proteomic and lipidomic changes. Mass Spectrometry Imaging (MSI) combined with fluorescence imaging and label free proteomics, revealed insight into the brain's lipidome and proteome within the FCD type II affected region in the mouse model. MSI visualized disrupted neuronal migration and differential lipid distribution including a reduction in sulfatides in the FCD type II-affected region, which play a role in brain myelination. MSI-guided laser capture microdissection (LMD) was conducted on FCD type II and control regions, followed by label free proteomics, revealing changes in myelination pathways by oligodendrocytes. Surgical resections of FCD type IIb and postmortem human cortex were analyzed by bulk transcriptomics to unravel the interplay between genetic mutations and molecular changes in FCD type II. Our comparative analysis of protein pathways and enriched Gene Ontology pathways related to myelination in the FCD type II-affected mouse model and human FCD type IIb transcriptomics highlights the animal model's translational value. This dual approach, including mouse model proteomics and human transcriptomics strengthens our understanding of the functional consequences arising from somatic mutations in FCD type II, as well as the identification of pathways that may be used as therapeutic strategies in the future.


Asunto(s)
Epilepsia , Malformaciones del Desarrollo Cortical de Grupo I , Proteómica , Animales , Humanos , Malformaciones del Desarrollo Cortical de Grupo I/genética , Malformaciones del Desarrollo Cortical de Grupo I/metabolismo , Malformaciones del Desarrollo Cortical de Grupo I/patología , Ratones , Masculino , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/genética , Femenino , Modelos Animales de Enfermedad , Encéfalo/metabolismo , Encéfalo/patología , Proteoma/metabolismo , Displasia Cortical Focal
2.
Small ; 19(31): e2206442, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36840669

RESUMEN

Carbon Dots (CDs) are luminescent quasi-spherical nanoparticles, possessing water solubility, high biocompatibility, and tunable chemical and physical properties for a wide range of applications, including nanomedicine and theranostics. The evaluation of new purification criteria, useful to achieve more reliable CDs, free from the interference of artifacts, is currently an object of debate in the field. Here, new CDs doped with gadolinium (Gd (III)), named Gd@CNDs, are presented as multifunctional probes for Magnetic Resonance Imaging (MRI). This new system is a case of study, to evaluate and/or combine different purification strategies, as a crucial approach to generate CDs with a better performance. Indeed, these new amorphous Gd@CNDs display good homogeneity, and they are free from emissive side products. Gd@CNDs (7-10 nm) contain 7% of Gd (III) w/w, display suitable and stable longitudinal relaxivity (r1 ) and with emissive behavior, therefore potentially useful for both MR and fluorescence imaging. They show good biocompatibility in both cellular and in vivo studies, cell permeability, and the ability to generate contrast in cellular pellets. Finally, MRI recording T1 -weighted images on mice after intravenous injection of Gd@CNDs, show signal enhancement in the liver, spleen, and kidney 30 min postinjection.


Asunto(s)
Medios de Contraste , Gadolinio , Animales , Ratones , Medios de Contraste/química , Gadolinio/química , Carbono/química , Imagen por Resonancia Magnética/métodos , Imagen Óptica
3.
J Biol Inorg Chem ; 28(8): 711-723, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37768364

RESUMEN

In this work, two analogous coumarin-thio and semicarbazone hybrid compounds were prepared and evaluated as a potential antichagasic agents. Furthermore, palladium and platinum complexes with the thiosemicarbazone derivative as ligand (L1) were obtained in order to establish the effect of metal complexation on the antiparasitic activity. All compounds were fully characterized both in solution and in solid state including the resolution of the crystal structure of the palladium complex by X-ray diffraction methods. Unexpectedly, all experimental and theoretical characterizations in the solid state, demonstrated that the obtained palladium and platinum complexes are structurally different: [PdCl(L1)] and [PtCl2(HL1)]. All the studied compounds lower the proliferation of the amastigote form of Trypanosoma cruzi while some of them also have an effect on the trypomastigote stage. Additionally, the compounds inhibit T. cruzi release from host cells in variable extents. The Pd compound presented a remarkable profile in all the in vitro experiments, and it showed no toxicity for mammalian cells in the assayed concentrations. In this sense, in vivo experiments were performed for this compound using an acute model of Chagas disease. Results showed that the complex significantly lowered the parasite count in the mice blood with no significant toxicity.


Asunto(s)
Tiosemicarbazonas , Tripanocidas , Trypanosoma cruzi , Animales , Ratones , Paladio/farmacología , Paladio/química , Tiosemicarbazonas/farmacología , Tiosemicarbazonas/química , Ligandos , Parasitemia , Platino (Metal)/química , Tripanocidas/farmacología , Cumarinas/farmacología , Mamíferos
4.
Environ Res ; 228: 115869, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-37044166

RESUMEN

Ciguatoxins (CTXs) are marine neurotoxins that cause ciguatera poisoning (CP), mainly through the consumption of fish. The distribution of CTXs in fish is known to be unequal. Studies have shown that viscera accumulate more toxins than muscle, but little has been conducted on toxicity distribution in the flesh, which is the main edible part of fish, and the caudal muscle is also most commonly targeted for the monitoring of CTXs in the Canary Islands. At present, whether this sample is representative of the toxicity of an individual is undisclosed. This study aims to assess the distribution of CTXs in fish, considering different muscle samples, the liver, and gonads. To this end, tissues from four amberjacks (Seriola spp.) and four dusky groupers (Epinephelus marginatus), over 16.5 kg and captured in the Canary Islands, were analyzed by neuroblastoma-2a cell-based assay. Flesh samples were collected from the extraocular region (EM), head (HM), and different areas from the fillet (A-D). In the amberjack, the EM was the most toxic muscle (1.510 CTX1B Eq·g-1), followed by far for the caudal section of the fillet (D) (0.906 CTX1B Eq·g-1). In the dusky grouper flesh samples, D and EM showed the highest toxicity (0.279 and 0.273 CTX1B Eq·g-1). In both species, HM was one of the least toxic samples (0.421 and 0.166 CTX1B Eq·g-1). The liver stood out for its high CTX concentration (3.643 and 2.718 CTX1B Eq·g-1), as were the gonads (1.620 and 0.992 CTX1B Eq·g-1). According to these results, the caudal muscle next to the tail is a reliable part for use in determining the toxicity of fish flesh to guarantee its safe consumption. Additionally, the analysis of the liver and gonads could provide further information on doubtful specimens, and be used for CTX monitoring in areas with an unknown prevalence of ciguatera.


Asunto(s)
Lubina , Intoxicación por Ciguatera , Ciguatoxinas , Animales , Ciguatoxinas/toxicidad , Ciguatoxinas/análisis , Intoxicación por Ciguatera/epidemiología , Peces , Alimentos Marinos/análisis , Hígado/química
5.
Molecules ; 28(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36677957

RESUMEN

Searching for new copper compounds which may be useful as antitumor drugs, a series of new [Cu(L-dipeptide)(batho)] (batho:4,7-diphenyl-1,10-phenanthroline, L-dipeptide: Gly-Val, Gly-Phe, Ala-Gly, Ala-Ala, Ala-Phe, Phe-Ala, Phe-Val and Phe-Phe) complexes were synthesized and characterized. To interpret the experimental IR spectra, [Cu(ala-gly)(batho)] was modelled in the gas phase using DFT at the B3LYP/LANL2DZ level of theory and the calculated vibrational frequencies were analyzed. Solid-state characterization is in agreement with pentacoordinate complexes of the general formula [Cu(L-dipeptide)(batho)]·x solvent, similar to other [Cu(L-dipeptide)(diimine)] complexes. In solution, the major species are heteroleptic, as in the solid state. The mode of binding to the DNA was evaluated by different techniques, to understand the role of the diimine and the dipeptide. To this end, studies were also performed with complexes [CuCl2(diimine)], [Cu(L-dipeptide)(diimine)] and free diimines, with phenanthroline, neocuproine and 3,4,7,8-tetramethyl-phenanthroline. The cytotoxicity of the complexes was determined on human cancer cell lines MDA-MB-231, MCF-7 (breast, the first triple negative), and A549 (lung epithelial) and non-tumor cell lines MRC-5 (lung) and MCF-10A (breast). [Cu(L-dipeptide)(batho)] complexes are highly cytotoxic as compared to cisplatin and [Cu(L-dipeptide)(phenanthroline)] complexes, being potential candidates to study their in vivo activity in the treatments of aggressive tumors for which there is no curative pharmacological treatment.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Humanos , Cobre/química , Fenantrolinas/farmacología , Fenantrolinas/química , Complejos de Coordinación/química , Antineoplásicos/química , ADN/química , Dipéptidos/farmacología , Dipéptidos/química
6.
Indian J Plast Surg ; 56(2): 124-129, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37153332

RESUMEN

Background Craniofacial fibrous dysplasia (CFD) is an uncommon benign condition in which a bone is replaced by fibrous tissue. An adequate clinical characterization considering the number of affected bones and functional impairment is important to determine the most effective surgical intervention for its management. This study aims to present our institution's experience in the evaluation and management of CFD. Methods This was a retrospective study that included patients with CFD managed at our institution. Data included demographic characteristics, afflicted bones, surgical procedures performed, and recurrence. Results are presented as mean and percentages. Recurrence-free years and association between the type of surgery and recurrence was evaluated. Results Eighteen patients were included (11 females, 61%). The zygomatic, maxillary, and frontal bones were the most commonly affected with eight (18%) cases each. The most common procedure was bone burring, with 36 procedures. Recurrence was more prevalent after burring (58.3%) and occurred earlier than in the bone resection group (13 vs. 15 years, p > 0.05). Conclusion Surgery continues to be the cornerstone of CFD treatment. Bone burring is effective for debulking and contouring but increases the risk for recurrence. An individualized approach should be tailored according to the anatomical location of the disease, type of CFD, behavior of the lesion, and accompanying clinical complaints.

7.
J Biol Inorg Chem ; 27(4-5): 431-441, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35524804

RESUMEN

New compounds to fight cancer are needed due to cancer high incidence and lack of curative treatments for several classes of this disease. Metal-based coordination compounds offer a variety of molecules that can turn into drugs. Among them, coordination copper complexes are emerging as an attractive class of compounds for cancer treatment. A series of [Cu(L-dipeptide)(tmp)] (tmp = 3,4,7,8-tetramethyl-1,10-phenanthroline) complexes were synthesized and characterized in the solid state, including the determination of the crystalline structure of [Cu(Gly-Gly)(tmp)]·3.5 H2O and [Cu2Cl4(tmp)2]. The complexes were studied in solution, where the major species are also ternary ones. The lipophilicity of the complexes was determined and the binding to the DNA was evaluated, suggesting that it occurs in the DNA's major groove. The cytotoxicity of the complexes was evaluated on different cancer cell lines: human metastatic breast adenocarcinoma MDA-MB-231 (triple negative, ATCC: HTB-26), MCF-7 (ATCC: HTB-22), SK-BR-3 (ATCC: HTB-30), human lung epithelial carcinoma A549 (ATCC: CCL-185), cisplatin resistant-human ovarian carcinoma A2780cis (SIGMA) and nontumoral cell lines: MRC-5 (lung; ATCC: CCL-171) and MCF-10A (breast, ATCC: CRL-10317). [Cu(L-dipeptide)(tmp)] complexes are highly cytotoxic as compared to [Cu(L-dipeptide)(phenanthroline)] and cisplatin. Therefore, [Cu(L-dipeptide)(tmp)] complexes are promising candidates to have their in vivo activity further studied toward new treatments for triple negative breast cancer and other aggressive tumors for which there is no curative pharmacological treatment to the date.


Asunto(s)
Antineoplásicos , Complejos de Coordinación , Neoplasias de la Mama Triple Negativas , Antineoplásicos/farmacología , Cisplatino/farmacología , Complejos de Coordinación/química , Cobre/química , Cobre/farmacología , ADN/química , Dipéptidos/química , Humanos , Células MCF-7 , Fenantrolinas/química
8.
Acta Vet Hung ; 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35895532

RESUMEN

Yersiniosis, caused by the fish pathogen Yersinia ruckeri, is a serious bacterial septicaemia affecting mainly salmonids worldwide. The acute infection may result in high mortality without apparent external disease signs, while the chronic one causes moderate to considerable mortality. Survivors of yersiniosis outbreaks become carriers. Y. ruckeri is able to adhere to, and to invade, phagocytic and non-phagocytic fish cells by using unknown molecular mechanisms. The aim of this study was to describe the kinetics of cell invasion by Y. ruckeri serotype O1 biotype 1 in a fish cell line (RTG-2) originating from rainbow trout gonads. The efficiency of invasion by Y. ruckeri was found to be temperature dependent, having a maximum at 20 °C. The bacterium was able to survive up to 96 h postinfection. The incubation of the cells at 4 °C and the pre-incubation of the bacteria with sugars or heat-inactivated antiserum significantly decreased the efficiency of invasion or even completely prevented the invasion of RTG-2 cells. These findings indicate that Y. ruckeri is capable of adhering to, entering and surviving within non-phagocytic cells, and that the intracellular environment may constitute a suitable niche for this pathogen that can favour the spread of infection and/or the maintenance of a carrier state of fish.

9.
Molecules ; 26(21)2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34770929

RESUMEN

In a search for new antitumoral agents, a series of homoleptic copper(II) complexes with amino acids and dipeptides, as well as heteroleptic complexes containing both dipeptides and 1,10-phenanthroline, were studied. Furthermore, a single-crystal structure containing alanyl-leucinato ([Cu3(AlaLeu)3(H2O)3(CO3)]·PF6·H2O), which is the first homotrinuclear carbonato-bridged copper(II) complex with a dipeptide moiety, is presented. To assess possible antitumor action mechanisms, we focused on the comparative analysis of pro- and antioxidant behaviors. Pro-oxidant activity, in which the reactive oxygen species (ROS) formed by the reaction of the complexes with H2O2 produce oxidative damage to 2-deoxy-d-ribose, was evaluated using the TBARS method. Additionally, the antioxidant action was quantified through the superoxide dismutase (SOD)-like activity, using a protocol based on the inhibitory effect of SOD on the reduction of nitrobluetetrazolium (NBT) by the superoxide anion generated by the xanthine/xanthine oxidase system. Our findings show that Cu-amino acid complexes are strong ROS producers and moderate SOD mimics. Conversely, Cu-dipeptide-phen complexes are good SOD mimics but poor ROS producers. The activity of Cu-dipeptide complexes was strongly dependent on the dipeptide. A DFT computational analysis revealed that complexes with high SOD-like activity tend to display a large dipole moment and condensed-to-copper charge, softness and LUMO contribution. Moreover, good ROS producers have higher global hardness and copper electrophilicity, lower copper softness and flexible and freely accessible coordination polyhedra.


Asunto(s)
Aminoácidos/química , Antineoplásicos/química , Antioxidantes/química , Complejos de Coordinación/química , Cobre/química , Dipéptidos/química , Oxidantes/química , Fenantrolinas/química , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Antioxidantes/síntesis química , Antioxidantes/farmacología , Técnicas de Química Sintética , Complejos de Coordinación/síntesis química , Complejos de Coordinación/farmacología , Teoría Funcional de la Densidad , Relación Dosis-Respuesta a Droga , Desarrollo de Medicamentos , Conformación Molecular , Estructura Molecular , Oxidantes/síntesis química , Oxidantes/farmacología , Oxidación-Reducción , Relación Estructura-Actividad
10.
Molecules ; 25(8)2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32331284

RESUMEN

Two new N'-heteroarylidene-1-carbohydrazide derivatives, namely; E-N'-[(pyridine-3-yl)methylidene]adamantane-1-carbohydrazide (1) and E-N'-[(5-nitrothiophen-2-yl)methylidene]adamantane-1-carbohydrazide (2), were produced via condensation of adamantane-1-carbohydrazide with the appropriate heterocyclic aldehyde. Both compounds were chemically and structurally characterized by 1H-NMR, 13C-NMR, infrared and UV-vis spectroscopies, and single crystal X-ray diffraction. The study was complemented with density functional theory calculations (DFT). The results show an asymmetrical charge distribution in both compounds, with the electron density accumulated around the nitrogen and oxygen atoms, leaving the positive charge surrounding the N-H and C-H bonds in the hydrazine group. Consequently, the molecules stack in an antiparallel fashion in the crystalline state, although the contribution of the polar contacts to the stability of the lattice is different for 1 (18%) and 2 (42%). This difference affects the density and symmetry of their crystal structures. Both molecules show intense UV-Vis light absorption in the range 200-350 nm (1) and 200-500 nm (2), brought about by π → π* electronic transitions. The electron density difference maps (EDDM) revealed that during light absorption, the electron density flows within the π-delocalized system, among the pyridyl/thiophene ring, the nitro group, and the N'-methyleneacetohydrazide moiety. Interestingly, compounds 1 and 2 constitute broad-spectrum antibacterial candidates, displaying potent antibacterial activity with minimal inhibitory concentration (MIC) values around 0.5-2.0 µg/mL. They also show weak or moderate antifungal activity against the yeast-like pathogenic fungus Candida albicans.


Asunto(s)
Adamantano/química , Antibacterianos/química , Antibacterianos/síntesis química , Antibacterianos/farmacología , Hidrazinas/síntesis química , Hidrazinas/farmacología , Técnicas de Química Sintética , Cristalografía por Rayos X , Teoría Funcional de la Densidad , Hidrazinas/química , Enlace de Hidrógeno , Modelos Moleculares , Conformación Molecular , Análisis Espectral , Relación Estructura-Actividad
11.
Appl Opt ; 58(6): 1587-1595, 2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30874049

RESUMEN

We assess and discuss several technical aspects of the multifractal statistical analysis applied to time series of dynamic speckle intensity signals. Due to the complexity of this goal, we implemented an optical setup that mimics the light scattering effect from the illuminated object using a spatial light modulator. The multifractal spectrum of the obtained dynamic speckle intensity signals is quantified by utilizing a mathematical framework based on the decomposition of wavelet leaders' functions. The propagated light that is scattered utilizing the spatial light modulator verifies the well-known first- and second-order statistics of the obtained speckle images and also a given temporal correlation function determined by a copula algorithm adding several classes of fractional Gaussian noises. To experimentally implement these issues, we load appropriate dynamic temporal phase screens in the spatial light modulator working on phase-only mode and guide the light propagation through an optical setup composed of a 4f correlator. Different types of statistical trends in the scaling properties as a function of frequency sampling, intensity signal discretization, mean size of speckle, temporal correlation length, and vanishing moments of the elected mother wavelet analysis are theoretically and experimentally tested and compared.

12.
BMC Public Health ; 19(1): 669, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31146722

RESUMEN

BACKGROUND: Thermal fogging of Insecticides is a vector control strategy used by the Medellin Secretary of Health to combat dengue. This method is employed during outbreaks to curb populations of potentially infectious adult mosquitoes and interrupt transmission cycles. While this strategy has been used in Medellin since 2007, in some years it has not reduced dengue cases as expected. Difficulties in the implementation of fumigation strategies, such as lack of opportunity for treatment and public perception may be factors that limit its utility. The objective of this study was to identify barriers that hinder the implementation of thermal fogging, as well as attitudes and beliefs that prevent its acceptance. METHODS: We used a cross-sectional observational study of mixed methods carried out in neighborhoods prioritized for fumigation treatment in Medellin, Colombia. First, we assessed the timeliness of treatment by determining the latency period between reported dengue cases and the implementation of fumigation in response to those cases. Next, we administered structured questionnaires to residents in the area of fumigation treatments (n = 4455 homes) to quantify acceptance and rejection, as well as factors associated with rejection. RESULTS: The median time between notification and treatment was 25 days (IQR 20.0-36.5). Fumigators were only able to treat 53.7% of total households scheduled for treatment; 9.6% rejected treatment, and treatment teams were unable to fumigate the remaining 36.7% of homes due to absent residents, no adults being present, and other reasons. The most frequent causes for rejection were residents being busy at the time of treatment (33.1%) and no interest in the treatment (24.5%). Other reasons for rejection include the perceptions that fumigation does not control pests other than mosquitoes (4.3%), that no mosquitoes were present in the home (3.3%), and that fumigation affects human health (3.1%). CONCLUSIONS: The high percentage of houses where it was not possible to perform fumigation limits control of the vector. Future strategies should consider more flexible treatment schedules and incorporate informational messages to educate residents about the safety and importance of treatment.


Asunto(s)
Dengue/prevención & control , Fumigación/estadística & datos numéricos , Insecticidas/administración & dosificación , Control de Mosquitos/métodos , Adulto , Colombia/epidemiología , Estudios Transversales , Dengue/epidemiología , Composición Familiar , Femenino , Fumigación/métodos , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Mosquitos Vectores , Características de la Residencia , Encuestas y Cuestionarios
13.
Gastrointest Endosc ; 87(4): 986-993, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29037773

RESUMEN

BACKGROUND AND AIM: Upper GI endoscopy (UGE) is essential for the diagnosis of gastrointestinal diseases. Mucus and bubbles may decrease mucosal visibility. The use of mucolytics could improve visualization. Our aim was to determine whether premedication with simethicone or simethicone plus N-acetylcysteine is effective in improving visibility during UGE. METHODS: This was a randomized, double-blinded, placebo-controlled trial with 2 control groups: no intervention and water 100 mL (W); and 3 intervention groups: simethicone 200 mg (S); S + N-acetylcysteine (NAC) 500 mg (S+NAC500); and S + NAC 1000 mg (S+NAC1000). The solution was ingested 20 minutes before UGE. Gastric visibility was evaluated in 4 segments with a previously described scale. A score of less than 7 points was defined as adequate visibility (AV). Water volume was used to improve visibility, and adverse reactions were evaluated as a secondary outcome. Multiple group comparison was performed using non-parametric one-way analysis of variance (ANOVA). RESULTS: Two hundred thirty patients were included in the study, 68% female, mean age 49 years. The most common indication for UGE was epigastric pain/dyspepsia (33%). AV was more frequent in the S+NAC500 and S+NAC1000 groups (65% and 67%) compared with no intervention (44%, P = .044) and water (41%, P = .022). The gastric total visibility scale (TVS) was significantly better in the S+NAC500 and S+NAC1000 groups compared with water (P = .03 and P = .008). Simethicone was not different from no intervention and water. S+NAC1000 required less water volume to improve visibility. No adverse reactions from the study drugs were observed. CONCLUSIONS: Premedication with S+NAC500 and S+NAC1000 improves visibility during UGE. The use of simethicone did not show improvements in gastric visibility. TVS was worse in patients using water alone. (Clinical trial registration number: NCT 01653171.).


Asunto(s)
Acetilcisteína/administración & dosificación , Antiespumantes/administración & dosificación , Endoscopía Gastrointestinal/métodos , Expectorantes/administración & dosificación , Mucosa Gástrica/diagnóstico por imagen , Simeticona/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Gastropatías/diagnóstico por imagen , Agua/administración & dosificación
14.
Rev Med Chil ; 146(3): 341-343, 2018 Mar.
Artículo en Español | MEDLINE | ID: mdl-29999104

RESUMEN

BACKGROUND: Our institution adopted the Objective Structured Clinical Evaluation (OSCE) format to assess clinical skills of International Medical Graduates (IMGs) aiming to practice in Chile. The OSCE has clear advantages over oral exams due to its objective and structured nature. AIM: To report our experience with OSCE. MATERIAL AND METHODS: A team consisting of clinical specialists and medical educators with expertise in clinical simulation organized this OSCE cycle. IMGs were required to pass four clinical examinations (Internal Medicine, Surgery, Pediatrics and Obstetrics & Gynecology) where their respective general medical competences were evaluated. The latter were carefully selected from those issued by the Chilean Medical Evaluation policy-making body (EUNACOM). Each OSCE consisted of ten stations. Initially conceived to last five minutes each, they were afterwards expanded to seven minutes, after it was realized that most candidates had never been exposed to an OSCE examination before. A post-hoc analysis according to qualitative and psychometric quality criteria followed each OSCE. RESULTS: The proportion of candidates passing the first two examinations of the cycle, were 65 and 75% respectively and reached 100% in the last ones. Lack of IMG familiarity with the OSCE system initially hampered their full expression of competencies. Extending the stations' duration to seven minutes subsequently rectified this situation, as well as potential adverse impacts on the validity of results. CONCLUSIONS: This evaluative process, which entails important consequences for the community and the IMGs, requires a meticulous and coordinated planning and post-hoc quality control.


Asunto(s)
Certificación , Competencia Clínica , Evaluación Educacional/métodos , Chile , Humanos , Reproducibilidad de los Resultados
15.
Bioorg Med Chem ; 25(19): 5055-5063, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-28734665

RESUMEN

Peptido sulfonyl fluoride derivatives were designed and synthesized containing a substituent on the alpha position (αPSFs) with respect to the sulfonyl fluoride electrophilic trap. The chemical reactivity of these α-substituted amino sulfonyl fluorides was studied and compared with the previously described ß-substituted amino sulfonyl fluorides in order to get a deeper insight into the importance of the immediate structural environment of the sulfonyl fluoride moiety. Unfortunately, the poor solubility of the resulting αPSFs precluded a proper evaluation of their biological activity.


Asunto(s)
Diseño de Fármacos , Peptidomiméticos/química , Peptidomiméticos/farmacología , Inhibidores de Proteasoma/química , Inhibidores de Proteasoma/farmacología , Ácidos Sulfínicos/química , Ácidos Sulfínicos/farmacología , Aminoácidos/síntesis química , Aminoácidos/química , Aminoácidos/farmacología , Humanos , Peptidomiméticos/síntesis química , Inhibidores de Proteasoma/síntesis química , Solubilidad , Ácidos Sulfínicos/síntesis química
16.
Bioorg Med Chem ; 24(16): 3429-35, 2016 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-27316540

RESUMEN

The success of inhibition of the proteasome by formation of covalent bonds is a major victory over the long held-view that this would lead to binding the wrong targets and undoubtedly lead to toxicity. Great challenges are now found in uncovering ensembles of new moieties capable of forming long lasting ties. We have introduced peptido sulfonyl fluorides for this purpose. Tuning the reactivity of this electrophilic trap may be crucial for modulating the biological action. Here we describe incorporation of a vinyl moiety into a peptido sulfonyl fluoride backbone, which should lead to a combined attack of the proteasome active site threonine on the double bond and the sulfonyl fluoride. Although this led to strong proteasome inhibitors, in vitro studies did not unambiguously demonstrate the formation of the proposed seven-membered ring structure. Possibly, formation of a seven-membered covalent adduct with the proteosomal active site threonine can only be achieved within the context of the enzyme. Nevertheless, this dual warhead concept may provide exclusive possibilities for duration and selectivity of proteasome inhibition.


Asunto(s)
Fluoruros/química , Péptidos/química , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Inhibidores de Proteasoma/farmacología , Sulfonas/química , Espectroscopía de Resonancia Magnética con Carbono-13 , Cromatografía Líquida de Alta Presión , Espectroscopía de Protones por Resonancia Magnética , Espectrometría de Masa por Ionización de Electrospray
17.
Neurobiol Dis ; 83: 100-14, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26341542

RESUMEN

Seizures are common during the neonatal period, often due to hypoxic-ischemic encephalopathy and may contribute to acute brain injury and the subsequent development of cognitive deficits and childhood epilepsy. Here we explored short- and long-term consequences of neonatal hypoxia-induced seizures in 7 day old C57BL/6J mice. Seizure activity, molecular markers of hypoxia and histological injury were investigated acutely after hypoxia and response to chemoconvulsants and animal behaviour was explored at adulthood. Hypoxia was induced by exposing pups to 5% oxygen for 15 min (global hypoxia). Electrographically defined seizures with behavioral correlates occurred in 95% of these animals and seizures persisted for many minutes after restitution of normoxia. There was minimal morbidity or mortality. Pre- or post-hypoxia injection of phenobarbital (50mg/kg) had limited efficacy at suppressing seizures. The hippocampus from neonatal hypoxia-seizure mice displayed increased expression of vascular endothelial growth factor and the immediate early gene c-fos, minimal histological evidence of cell injury and activation of caspase-3 in scattered neurons. Behavioral analysis of mice five weeks after hypoxia-induced seizures detected novel anxiety-related and other behaviors, while performance in a spatial memory test was similar to controls. Seizure threshold tests with kainic acid at six weeks revealed that mice previously subject to neonatal hypoxia-induced seizures developed earlier, more frequent and longer-duration seizures. This study defines a set of electro-clinical, molecular, pharmacological and behavioral consequences of hypoxia-induced seizures that indicate short- and long-term deleterious outcomes and may be a useful model to investigate the pathophysiology and treatment of neonatal seizures in humans.


Asunto(s)
Ansiedad/etiología , Corteza Cerebral/fisiopatología , Hipocampo/metabolismo , Hipoxia/complicaciones , Convulsiones/etiología , Convulsiones/fisiopatología , Animales , Animales Recién Nacidos , Anticonvulsivantes/administración & dosificación , Ansiedad/fisiopatología , Conducta Animal/fisiología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/patología , Electroencefalografía , Femenino , Hipocampo/patología , Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Actividad Motora , Neuronas/metabolismo , Neuronas/patología , Fenobarbital/administración & dosificación , Convulsiones/metabolismo , Factores de Tiempo , Factor A de Crecimiento Endotelial Vascular/metabolismo
18.
Emerg Infect Dis ; 20(2): 269-71, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24447792

RESUMEN

A systemic morbillivirus infection was diagnosed postmortem in a juvenile bottlenose dolphin stranded in the eastern North Atlantic Ocean in 2005. Sequence analysis of a conserved fragment of the morbillivirus phosphoprotein gene indicated that the virus is closely related to dolphin morbillivirus recently reported in striped dolphins in the Mediterranean Sea.


Asunto(s)
Delfín Mular/virología , Infecciones por Morbillivirus/veterinaria , Morbillivirus/clasificación , Proteínas Virales/clasificación , Animales , Femenino , Morbillivirus/genética , Morbillivirus/aislamiento & purificación , Infecciones por Morbillivirus/virología , Filogenia , España , Proteínas Virales/genética
19.
Retina ; 34(10): 1985-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24736465

RESUMEN

PURPOSE: To compare the incident rates of sustained elevation of intraocular pressure (IOP) after uncomplicated pars plana vitrectomy for idiopathic epiretinal membrane and the unoperated fellow eye. METHODS: Retrospective multicenter study of 198 patients who underwent pars plana vitrectomy for an idiopathic epiretinal membrane that was followed for at least 12 months. The diagnosis of sustained IOP elevation was defined as an elevation of IOP ≥ 24 mmHg or an increase of ≥ 5 mmHg in the IOP from baseline on 2 separate visits that warranted the initiation of ocular hypotensive therapy. The main outcome measured was the development of sustained IOP elevation as defined above. RESULTS: Patients were followed for an average of 47.3 ± 24 months (range, 12-106 months). In the vitrectomized eyes, 38 of the 198 (19.2%) patients developed elevated IOP compared with 9 of the 198 (4.5%) unoperated fellow eyes (P < 0.0001, Fisher exact test; odds ratio, 4.988). Possible risk factors include a family history of open-angle glaucoma (P = 0.0004 Fisher exact test; odds ratio, 7.206) and cataract surgery (P = 0.0270 Fisher exact test; odds ratio, 2.506). CONCLUSION: Uncomplicated PPV seems to increase the IOP, particularly in those who are pseudophakic and have a family history of open-angle glaucoma. This increase in IOP may lead to glaucomatous damage if not managed appropriately. Patients with a previous PPV need to be followed by an ophthalmologist to monitor the IOP in the vitrectomized eye.


Asunto(s)
Membrana Epirretinal/cirugía , Presión Intraocular , Hipertensión Ocular/etiología , Complicaciones Posoperatorias , Vitrectomía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Hipertensión Ocular/diagnóstico , Oftalmología/organización & administración , Organización Panamericana de la Salud/organización & administración , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA