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We report four cases of Taenia saginata taeniasis in different urban communities of Aragua state, Venezuela. After subsequent treatment with praziquantel and a saline purge, adult tapeworms were collected from all four patients and demonstrated to be T. saginata by morphological and molecular characterization. The finding of T. saginata in four distinct and separate urban municipalities of the Aragua state indicates the pertinence of rigorous meat inspection, and the importance of establishing parasite prevalence in human and bovine Venezuelan populations.
Assuntos
Taenia saginata/isolamento & purificação , Teníase/parasitologia , Animais , Anti-Helmínticos/administração & dosagem , Feminino , Humanos , Taenia saginata/classificação , Taenia saginata/genética , Teníase/tratamento farmacológico , População Urbana , VenezuelaRESUMO
The p75 neurotrophin receptor (p75, also known as NGFR) is a multifaceted signalling receptor that regulates neuronal physiology, including neurite outgrowth, and survival and death decisions. A key cellular aspect regulating neurotrophin signalling is the intracellular trafficking of their receptors; however, the post-endocytic trafficking of p75 is poorly defined. We used sympathetic neurons and rat PC12 cells to study the mechanism of internalisation and post-endocytic trafficking of p75. We found that p75 internalisation depended on the clathrin adaptor protein AP2 and on dynamin. More surprisingly, p75 evaded the lysosomal route at the level of the early endosome, instead accumulating in two different types of endosomes, Rab11-positive endosomes and multivesicular bodies (MVBs) positive for CD63, a marker of the exosomal pathway. Consistently, depolarisation by KCl induced the liberation of previously endocytosed full-length p75 into the extracellular medium in exosomes. Thus, p75 defines a subpopulation of MVBs that does not mature to lysosomes and is available for exosomal release by neuronal cells.
Assuntos
Endossomos/metabolismo , Exossomos/metabolismo , Lisossomos/metabolismo , Corpos Multivesiculares/metabolismo , Neurônios/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Animais , Microscopia de Fluorescência , Proteínas do Tecido Nervoso , Células PC12 , Interferência de RNA , Ratos , Receptores de Fatores de Crescimento , Receptores de Fator de Crescimento Neural/genéticaRESUMO
African swine fever (ASF) is a lethal infectious disease that affects domestic and wild pigs. This complex virus has already affected five continents and more than 70 countries and is considered to be the main threat to the global swine industry. The disease can potentially be transmitted directly through contact with infectious animals, or indirectly by means of contaminated feed or environments. Nevertheless, the knowledge regarding the transmission patterns of different ASF virus isolates at the wildlife-livestock interface is still limited. We have, therefore, assessed the potential transmission of an attenuated ASF virus isolate between infectious wild boar and directly exposed domestic pig. We registered 3,369 interspecific interactions between animals, which were brief and mostly initiated by wild boar. The major patterns observed during the study were head-to-head contact owing to sniffing, thus suggesting a high probability of pathogen transmission. However, only one of the five domestic pigs had a short period of viremia and became serologically positive for ASF virus antibodies. It was additionally discovered that the wild boar did not transmit the virulent virus isolate to the domestic pigs, which suggests that the presence of attenuated ASF virus isolates in affected areas may control the spreading of other more virulent isolates. These outcomes may help make decisions related to large-scale targeted management actions against ASF in field conditions.
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BACKGROUND: Colombia is currently the world's main recipient country for Venezuelan migrants, and women represent a high proportion of them. This article presents the first report of a cohort of Venezuelan migrant women entering Colombia through Cúcuta and its metropolitan area. The study aimed to describe the health status and access to healthcare services among Venezuelan migrant women in Colombia with irregular migration status, and to analyze changes in those conditions at a one-month follow-up. METHODS: We carried out a longitudinal cohort study of Venezuelan migrant women, 18 to 45 years, who entered Colombia with an irregular migration status. Study participants were recruited in Cúcuta and its metropolitan area. At baseline, we administered a structured questionnaire including sociodemographic characteristics, migration history, health history, access to health services, sexual and reproductive health, practice of early detection of cervical cancer and breast cancer, food insecurity, and depressive symptoms. The women were again contacted by phone one month later, between March and July 2021, and a second questionnaire was applied. RESULTS: A total of 2,298 women were included in the baseline measurement and 56.4% could be contacted again at the one-month follow-up. At the baseline, 23.0% of the participants reported a self-perceived health problem or condition in the past month and 29.5% in the past 6 months, and 14.5% evaluated their health as fair or poor. A significant increase was found in the percentage of women who reported a self-perceived health problem during the past month (from 23.1% to 31.4%; p<0.01); as well as in the share who reported moderate, severe, or extreme difficulty working or performing daily chores (from 5.5% to 11.0%; p = 0.03) and who rated their health as fair (from 13.0% to 31.2%; p<0.01). Meanwhile, the percentage of women with depressive symptoms decreased from 80.5% to 71.2% (p<0.01). CONCLUSION: This report presents initial information on the health status of Venezuelan migrant women in Colombia, and is a starting point for further longer longitudinal follow-ups to assess changes over time in health conditions.
Assuntos
Migrantes , Humanos , Feminino , Venezuela/epidemiologia , Colômbia/epidemiologia , Estudos Longitudinais , Inquéritos EpidemiológicosRESUMO
Preeclampsia (PE) is a hypertensive disease that affects pregnant women after 20 weeks of gestation. This disease is associated with an important risk of maternal and fetal mortality. PE is described as a placental pathology because, after delivery, most women recover normal arterial pressure. Poor invasion of the spiral arteries is a phenomenon well described in PE; this leads to a hypoxic uterine bed and imbalance of antiangiogenic and proangiogenic factors in the uteroplacental region, which in turn triggers the disease phenotype. The causes of the pathology are unclear; nevertheless, numerous approaches, including next-generation sequencing, association, and case control and miRNA studies, have shed light on the genetic/molecular basis of PE. These studies help us better understand the disease to advance new treatment strategies.
Assuntos
Hipertensão , MicroRNAs , Pré-Eclâmpsia , Feminino , Humanos , MicroRNAs/genética , Placenta , Fator de Crescimento Placentário , Pré-Eclâmpsia/genética , GravidezRESUMO
The biomedical potential of the edible red seaweed Agarophyton chilense (formerly Gracilaria chilensis) has not been explored. Red seaweeds are enriched in polyunsaturated fatty acids and eicosanoids, which are known natural ligands of the PPARγ nuclear receptor. PPARγ is the molecular target of thiazolidinediones (TZDs), drugs used as insulin sensitizers to treat type 2 diabetes mellitus. Medical use of TZDs is limited due to undesired side effects, a problem that has triggered the search for selective PPARγ modulators (SPPARMs) without the TZD side effects. We produced Agarophyton chilense oleoresin (Gracilex®), which induces PPARγ activation without inducing adipocyte differentiation, similar to SPPARMs. In a diet-induced obesity model of male mice, we showed that treatment with Gracilex® improves insulin sensitivity by normalizing altered glucose and insulin parameters. Gracilex® is enriched in palmitic acid, arachidonic acid, oleic acid, and lipophilic antioxidants such as tocopherols and ß-carotene. Accordingly, Gracilex® possesses antioxidant activity in vitro and increased antioxidant capacity in vivo in Caenorhabditis elegans. These findings support the idea that Gracilex® represents a good source of natural PPARγ ligands and antioxidants with the potential to mitigate metabolic disorders. Thus, its nutraceutical value in humans warrants further investigation.
Assuntos
Gracilaria/química , Resistência à Insulina/fisiologia , Obesidade/metabolismo , PPAR gama/metabolismo , Extratos Vegetais , Animais , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/farmacologia , Caenorhabditis elegans , Modelos Animais de Doenças , Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/farmacologiaRESUMO
99mTc-tilmanocept is a novel radiopharmaceutical for sentinel lymph node (SLN) biopsy in breast cancer. Our aim was to describe results with 99mTc-tilmanocept in a heterogeneous group of breast cancer patients scheduled for SLN biopsy. Methods: Radiotracer preparation followed the manufacturer's indications. Local protocols for SLN detection within 9 participant centers were not changed for the entire duration of the study. In total, 344 patients with T1-T4, N0-N2 breast cancer (352 lesions) were included. Superficial (intradermal or periareolar) or deep (peritumoral or intratumoral) injections were performed. The doses were adjusted depending on the scheduled time for surgery. Results: Lymphoscintigraphy was able to depict at least 1 SLN in 339 of 352 breast lesions (96.3%), and the intraoperative SLN detection rate reached 97.2%. On univariable analysis, SLN detection rates did not differ by age, clinical T or N stage, tumor location, histologic subtype, or prior neoadjuvant therapy. Lymphoscintigraphy showed higher SLN detection in patients with a normal weight (body mass index < 25) than in those who were overweight or obese (body mass index ≥ 25), at 99.2% versus 94.6%, respectively (P = 0.031). The proportion of patients with preoperative lymphoscintigraphic detection or excised SLNs was higher with superficial than deep injections. Reinjected cases were significantly lower when superficial injection was chosen first (P < 0.001). Injection site and the tumor markers human epidermal growth factor receptor 2 and estrogen receptor had an impact on preoperative SLN visualization and intraoperative localization. In 80 cases, SLN biopsy resulted in a positive lymph node. During a mean follow-up of 19 mo, no axillary recurrences were observed. Conclusion: Whatever the protocol, 99mTc-tilmanocept showed good results in a heterogeneous breast cancer population, although the best results were achieved when a superficial injection was chosen.
Assuntos
Neoplasias da Mama/patologia , Dextranos , Mananas , Biópsia de Linfonodo Sentinela , Pentetato de Tecnécio Tc 99m/análogos & derivados , Adulto , Idoso , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Feminino , Humanos , Linfocintigrafia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Período Pré-Operatório , Traçadores RadioativosRESUMO
Clopidogrel, an oral platelet P2Y12 receptor blocker, is used in the treatment of acute coronary syndrome. Interindividual variability in treatment response and the occurrence of adverse effects has been attributed to genetic variants in CYP2C19. The analysis of relevant pharmacogenes in ethnically heterogeneous and poorly studied populations contributes to the implementation of personalized medicine. We analyzed the coding and regulatory regions of CYP2C19 in 166 patients with acute coronary syndrome (ACS) treated with clopidogrel. The allele frequencies of CYP2C19 alleles *1, *2, *4, *17, *27 and *33 alleles were 86.1%, 7.2%, 0.3%, 10.2%, 0.3% and 0.3%, respectively. A new potentially pathogenic mutation (p.L15H) and five intronic variants with potential splicing effects were detected. In 14.4% of the patients, a new haplotype in strong linkage disequilibrium was identified. The clinical outcome indicated that 13.5% of the patients presented adverse drugs reactions with a predominance of bleeding while 25% of these patients were carriers of at least one polymorphic allele. We propose that new regulatory single-nucleotide variants (SNVs) might potentially influence the response to clopidogrel in Colombian individuals.
RESUMO
S-nitrosylation of several Ca2+ regulating proteins in response to ß-adrenergic stimulation was recently described in the heart; however the specific nitric oxide synthase (NOS) isoform and signaling pathways responsible for this modification have not been elucidated. NOS-1 activity increases inotropism, therefore, we tested whether ß-adrenergic stimulation induces NOS-1-dependent S-nitrosylation of total proteins, the ryanodine receptor (RyR2), SERCA2 and the L-Type Ca2+ channel (LTCC). In the isolated rat heart, isoproterenol (10 nM, 3-min) increased S-nitrosylation of total cardiac proteins (+46±14%) and RyR2 (+146±77%), without affecting S-nitrosylation of SERCA2 and LTCC. Selective NOS-1 blockade with S-methyl-L-thiocitrulline (SMTC) and Nω-propyl-l-arginine decreased basal contractility and relaxation (-25-30%) and basal S-nitrosylation of total proteins (-25-60%), RyR2, SERCA2 and LTCC (-60-75%). NOS-1 inhibition reduced (-25-40%) the inotropic response and protein S-nitrosylation induced by isoproterenol, particularly that of RyR2 (-85±7%). Tempol, a superoxide scavenger, mimicked the effects of NOS-1 inhibition on inotropism and protein S-nitrosylation; whereas selective NOS-3 inhibitor L-N5-(1-Iminoethyl)ornithine had no effect. Inhibition of NOS-1 did not affect phospholamban phosphorylation, but reduced its oligomerization. Attenuation of contractility was abolished by PKA blockade and unaffected by guanylate cyclase inhibition. Additionally, in isolated mouse cardiomyocytes, NOS-1 inhibition or removal reduced the Ca2+-transient amplitude and sarcomere shortening induced by isoproterenol or by direct PKA activation. We conclude that 1) normal cardiac performance requires basal NOS-1 activity and S-nitrosylation of the calcium-cycling machinery; 2) ß-adrenergic stimulation induces rapid and reversible NOS-1 dependent, PKA and ROS-dependent, S-nitrosylation of RyR2 and other proteins, accounting for about one third of its inotropic effect.
Assuntos
Coração/fisiologia , Contração Miocárdica , Miocárdio/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Receptores Adrenérgicos beta/metabolismo , S-Nitrosotióis/metabolismo , Animais , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/metabolismo , Coração/efeitos dos fármacos , Isoproterenol/farmacologia , Masculino , Contração Miocárdica/efeitos dos fármacos , Miocárdio/citologia , Oxirredução/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Estrutura Quaternária de Proteína , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismoRESUMO
Se utilizaron dos polímeros hidrofílicos comúnmente empleados en la formulación de matrices de liberación extendida, hidroxipropil-metil-celulosa (HPMC, hipromelosa) y óxido de polietileno (PEO), junto con celulosa microcristalina y lactosa, con el objetivo de estudiar la cinética de liberación del diclofenaco sódico en los aparatos II y III de la USP, en un medio de disolución compendial y en medios biorrelevantes. La cinética de liberación predominante en el aparato II fue uno y en el aparato III, cero. El valor de las constantes n y k aplicando la ley del exponente, indicaron tanto para el aparato II como para el III, que no se presenta el efecto "burst" y que el mecanismo predominante en la liberación del fármaco, es la relajación y la erosión del polímero. Los resultados sugieren que la metodología de disolución en un medio biorrelevante es apropiada para discriminar entre formulaciones y para predecir el desempeño in vivo de tabletas de liberación extendida de diclofenaco sódico.
Two hydrophilic polymers commonly employed on the development of extended release products, hydroxypropyl-methyl-cellulose (HPMC, hypromellose) and polyethylene oxide (PEO) were formulated with microcrystalline cellulose or lactose in order to investigate the release kinetics of sodium diclofenac on USP apparatus II and III using a compendial or biorelevant media, respectively. The dominant release kinetic on apparatus II was first order and zero on apparatus III. The values of the kinetic constant (k) and the release exponent (n) from the Power Law Model indicated that there was no burst effect in none of the studied formulations, relaxation and polymer erosion was the dominant mechanism of drug release in both methods. The results suggest that biorelevant dissolution methodology is appropriate for the discrimination of formulations and prediction of in vivo performance of MR diclofenac sodium matrices.
RESUMO
En el presente estudio se realizó la estandarización de las condiciones de operación de algunas celdas de Franz, sistema que permite realizar la evaluación de la liberación de compuestos biológicamente activos como una de sus aplicaciones. Para ello se seleccionaron y caracterizaron dos complejos obtenidos entre Eudragit® y ácido benzoico como modelos a emplear, de acuerdo con su solubilidad. Se evaluó su comportamiento de liberación en diferentes condiciones operacionales del ensayo y los resultados se evaluaron empleando el modelo de Korsmeyer-Peppas y el análisis estadístico correspondiente. El análisis de Korsmeyer-Peppas demostró que el mecanismo de liberación del ácido benzoico se ajusta a la ley de difusión de Fick, en algunos casos. Las condiciones operacionales definidas para el ensayo de liberación en las celdas de Franz fueron las siguientes: la concentración del ácido benzoico en la dispersión de complejo en el compartimento donor, 0,07%; la velocidad de agitación, 400 rpm; el volumen de muestreo, 1 mL y la frecuencia de muestreo según un esquema determinado. Se demostró la reproducibilidad del ensayo de liberación en las condiciones operacionales definidas, mediante análisis de varianza.
This paper presents the studies carried out about the standardization of the operational conditions of some Franz Cells; this system allows evaluating the drug release, among others. To this purpose, two Eudragit E- benzoic acid complexes were selected and characterized, as models due to their solubility. After that, the outstanding operational variables were established and evaluated at different levels. The delivery profiles analysis applying the Korsmeyer-Peppas model showed that the release mechanism of benzoic acid was Fick diffusion, in some cases. The operational conditions: benzoic concentration in the complex dispersion in the donor compartment, 0,07%; agitation speed, 400 rpm; volume (1 mL) and frequency sampling according to specific scheme, were determined. The delivery assay reproducibility was demonstrated in the established operational conditions by statistically analysis (ANOVA).
RESUMO
Plasmodium falciparum, the causative agent of malaria, relies extensively on glycolysis coupled with homolactic fermentation during its blood-borne stages for energy production. Selective inhibitors of the parasite lactate dehydrogenase (LDH), central to NAD(+) regeneration, therefore potentially provide a route to new antimalarial drugs directed against a novel molecular target. A series of heterocyclic, azole-based compounds are described that preferentially inhibit P. falciparum LDH at sub-micromolar concentrations, typically at concentrations about 100-fold lower than required for human lactate dehydrogenase inhibition. Crystal structures show these competitive inhibitors form a network of interactions with amino acids within the active site of the enzyme, stacking alongside the nicotinamide ring of the NAD(+) cofactor. These compounds display modest activity against parasitized erythrocytes, including parasite strains with known resistance to existing anti-malarials and against Plasmodium berghei in BALB/c mice. Initial toxicity data suggest the azole derivatives have generally low cytotoxicity, and preliminary pharmoco-kinetic data show favorable bioavailability and circulation times. These encouraging results suggest that further enhancement of these structures may yield candidates suitable for consideration as new therapeutics for the treatment of malaria. In combination these studies also provide strong support for the validity of targeting the Plasmodium glycolytic pathway and, in particular, LDH in the search for novel anti-malarials.
Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Azóis/química , Azóis/farmacologia , L-Lactato Desidrogenase/antagonistas & inibidores , Plasmodium falciparum/efeitos dos fármacos , Plasmodium falciparum/enzimologia , Animais , Domínio Catalítico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Técnicas In Vitro , L-Lactato Desidrogenase/química , L-Lactato Desidrogenase/genética , Malária/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Mutagênese Sítio-Dirigida , Plasmodium berghei , Plasmodium falciparum/genética , Relação Estrutura-AtividadeRESUMO
Las matrices hidrofílicas son uno de los sistemas de liberación controlados más empleados a escala mundial. El reconocido éxito global de este tipo de sistemas está ligado a su manufactura por medio de tecnología convencional para la obtención de comprimidos, además de su bajo costo. Estos sistemas han sido objeto de investigación desde hace ya algunas décadas, mediante el uso de técnicas como la creación de imágenes a partir de resonancia magnética, calorimetría de barrido diferencial y la espectroscopia dieléctrica de baja frecuencia, entre otras. Varios autores han estudiado los diferentes estados del agua dentro de una matriz, así como el estado y los cambios en los estados de los materiales en el tiempo, con el fin de estudiar los mecanismos de cesión de los activos a partir de las matrices, así como para buscar modelos matemáticos que describan la evolución de la concentración en el tiempo. En la actualidad se cuenta con modelos matemáticos de gran utilidad que permiten identificar dichos mecanismos a partir de un análisis de los parámetros de los modelos y que conducen finalmente a predecir la velocidad de liberación a partir de estos sistemas.
The hydrophilic matrices are one of the most used controlled delivery systems in the world, due to the simple technology and low cost. A number of publications, over the last decades, have reported investigations in regard with the mechanisms of drug release from hydrophilic matrices. Nevertheless, the mechanisms of drug release from these systems continue to be a matter of debate. Differential scanning calorimetry, low frequency dielectric spectroscopy and nuclear magnetic resonance have been used to examine the distribution of water within ether cellulose matrices, as well as to describe the state of the materials inside the device. The objective is to study the release and hydration rate of hydrophilic matrices in order to contribute to the rationalization of the design of these controlled release systems through mathematical modeling and to obtain a better knowledge of the processes that occur during the release of the drug.
Assuntos
Celulose/análogos & derivados , Celulose/farmacologia , Difusão , Erosão , Modelos TeóricosRESUMO
Considerando que a nivel mundial el diseño de nuevos fármacos involucra un costo muy alto, tanto en tiempo como en dinero, la preocupación en los últimos años se ha centrado en diseñar y desarrollar medicamentos que controlen la liberación del activo, de manera que se les pueda dar un valor agregado a moléculas ya existentes, lo que significa una menor inversión en términos de costos. En este sentido, para la presente revisión se seleccionó el sistema de liberación osmótica, uno de los medicamentos de liberación controlada con más participación en el mercado en el mundo. En este escrito se muestran los aspectos fisicoquímicos relacionados con su formulación, las clases de sistemas osmóticos de administración oral existentes y sus aplicaciones, así como el estado del arte en este contexto. Hacia el futuro, estos sistemas osmóticos parecen ser muy promisorios, debido a sus ventajas y gran mercado potencial
Assuntos
Administração Oral , Composição de Medicamentos , Pressão OsmóticaRESUMO
En los medicamentos de liberación modificada de administración peroral, es importante garantizar que la liberación del principio activo, sea independiente del pH, para evitar variaciones significativas en los niveles sanguíneos, que puedan conducir a fallas terapéuticas, o a manifestaciones de toxicidad. Uno de los medicamentos que más se comercializa en formas de liberación modificada es la teofilina, existiendo en el mercado más de una docena de marcas de diversos sistemas de entrega como tabletas, cápsulas con pellets o con microgránulos y en varias concentraciones como 100, 125, 200 y 300 mg. En este trabajo se presentan los resultados de un producto comercializado como microgránulos encapsulados con 125 y 300 mg de teofilina. Se evaluó la liberación de la teofilina a 8 valores de pH que cubren las condiciones del tracto gastrointestinal. Se encontró que la liberación de la teofilina se ajusta a lo establecido en la USP 25 para los ensayos 2 y 4, pero tanto la cinética como la velocidad de liberación son altamente dependientes del pH. Para valores de pH por debajo de 6.4 el proceso de liberación se ajusta a un modelo de primer orden cinético con una vida media de disolución que va de 161 min. hasta 247 min. a medida que el pH se acidifica. Para un pH de 6.4 a 8.0 la disolución de la teofilina se ajusta a un modelo de orden cero y la vida media de disolución disminuye de 92 a 27 minutos, en la medida que el pH se vuelve más alcalino