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1.
Cell Rep ; 35(13): 109319, 2021 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-34192531

RESUMO

Neonates are highly susceptible to bacterial meningitis as compared to children and adults. Group B streptococcus (GBS) is a major cause of neonatal meningitis. Neonatal meningitis can result from GBS intestinal colonization and translocation across the intestinal barrier (IB). Here, we show that the immaturity of the neonatal intestinal microbiota leads to low resistance to GBS intestinal colonization and permissiveness of the gut-vascular barrier. Moreover, the age-dependent but microbiota-independent Wnt activity in intestinal and choroid plexus (CP) epithelia results in a lower degree of cell-cell junctions' polarization, which favors bacterial translocation. This study thus reveals that neonatal susceptibility to GBS meningitis results from the age-dependent immaturity of the intestinal microbiota and developmental pathways associated with neonatal tissue growth, which both concur to GBS gut colonization, systemic dissemination, and neuroinvasion. Whereas the activation of developmental pathways is intrinsic to neonates, interventions aimed at maturing the microbiota may help prevent neonatal meningitis.


Assuntos
Microbioma Gastrointestinal , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Meningites Bacterianas/microbiologia , Meningites Bacterianas/patologia , Envelhecimento/patologia , Animais , Animais Recém-Nascidos , Bacteriemia/complicações , Bacteriemia/microbiologia , Plexo Corióideo/patologia , Suscetibilidade a Doenças , Células Epiteliais/metabolismo , Interações Hospedeiro-Patógeno , Junções Intercelulares/metabolismo , Mucosa Intestinal/irrigação sanguínea , Camundongos Endogâmicos C57BL , Streptococcus agalactiae/fisiologia , Via de Sinalização Wnt
2.
Sci Total Environ ; 788: 147820, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34029810

RESUMO

Polybrominated diphenyl ethers (PBDEs) and their methoxylated analogues (MeO-BDEs) are widely distributed in the environment. The main concern about the presence of PBDEs and MeO-BDEs in fish is due to their potential endocrine disruption effects in the specimens, and their potential risk to the health of human consumers. Considering these concerns, the goal of this study was to investigate the occurrence of PBDEs and MeO-BDEs in muscle tissues of blue shark (BSH), Prionace glauca, and yellowfin tuna (YFT), Thunnus albacares, caught in the Equatorial Atlantic Ocean (EAO), North-eastern Brazilian waters, and to evaluate the potential risk of human exposure by consumption. Muscle tissues of YFT and BSH were extracted using a Soxhlet apparatus and an Accelerated Solvent Extractor (ASE), respectively. PBDEs and MeO-BDEs were analysed by GC-NCI-MS. Concentrations of PBDEs ranged from not detected (nd) to 10 ng g-1 lipid weight (lw) in YFT muscle samples, while PBDE levels in BSH muscle samples ranged from

Assuntos
Éteres Difenil Halogenados , Tubarões , Animais , Oceano Atlântico , Brasil , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Humanos , Atum
3.
Mini Rev Med Chem ; 21(2): 171-185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32348220

RESUMO

The available scientific literature regarding tanshinones is very abundant, and after its review, it is noticeable that most of the articles focus on the properties of tanshinone I, cryptotanshinone, tanshinone IIA, sodium tanshinone IIA sulfonate and the dried root extract of Salvia miltiorrhiza (Tan- Shen). However, although these products have demonstrated important biological properties in both in vitro and in vivo models, their poor solubility and bioavailability have limited their clinical applications. For these reasons, many studies have focused on the search for new pharmaceutical formulations for tanshinones, as well as the synthesis of new derivatives that improve their biological properties. To provide new insights into the critical path ahead, we systemically reviewed the most recent advances (reported since 2015) on tanshinones in scientific databases (PubMed, Web of Science, Medline, Scopus, and Clinical Trials). With a broader perspective, we offer an update on the last five years of new research on these quinones, focusing on their synthesis, biological activity on noncommunicable diseases and drug delivery systems, to support future research on its clinical applications.


Assuntos
Abietanos/química , Diterpenos/química , Abietanos/síntese química , Abietanos/uso terapêutico , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Portadores de Fármacos/química , Medicamentos de Ervas Chinesas/síntese química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Doenças Neurodegenerativas/tratamento farmacológico , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/uso terapêutico , Salvia miltiorrhiza/química , Salvia miltiorrhiza/metabolismo
4.
Front Bioinform ; 1: 777101, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-36303792

RESUMO

Three-dimensional imaging is at the core of medical imaging and is becoming a standard in biological research. As a result, there is an increasing need to visualize, analyze and interact with data in a natural three-dimensional context. By combining stereoscopy and motion tracking, commercial virtual reality (VR) headsets provide a solution to this critical visualization challenge by allowing users to view volumetric image stacks in a highly intuitive fashion. While optimizing the visualization and interaction process in VR remains an active topic, one of the most pressing issue is how to utilize VR for annotation and analysis of data. Annotating data is often a required step for training machine learning algorithms. For example, enhancing the ability to annotate complex three-dimensional data in biological research as newly acquired data may come in limited quantities. Similarly, medical data annotation is often time-consuming and requires expert knowledge to identify structures of interest correctly. Moreover, simultaneous data analysis and visualization in VR is computationally demanding. Here, we introduce a new procedure to visualize, interact, annotate and analyze data by combining VR with cloud computing. VR is leveraged to provide natural interactions with volumetric representations of experimental imaging data. In parallel, cloud computing performs costly computations to accelerate the data annotation with minimal input required from the user. We demonstrate multiple proof-of-concept applications of our approach on volumetric fluorescent microscopy images of mouse neurons and tumor or organ annotations in medical images.

5.
Biosci. j. (Online) ; 36(1): 183-190, jan./feb. 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1049240

RESUMO

The present study aimed to evaluate the efficacy of traditionally used antibacterial plants (Euphorbia prostrata, Schinus molle, Brickellia veronicaefolia and Lepidium virginicum) in Santa Rosa Range in Guanajuato against major mastitis-causing pathogens. The selected plants were phytochemically screened for alkaloids, flavonoids, polyphenols, saponins, anthraquinone, cardiac glycosides, steroids and terpenoids. Moreover, to achieve the main purpose of the present research, extracts of selected plants were tested for in vitro antibacterial activity against Staphylococcus aureus, Escherichia coli, Shigella spp., Bacillus subtilis, Clavibacter spp., Proteus vulgaris and Salmonella spp. All these bacterial were isolated from clinical mastitis in dairy cows. The results indicated that the ethanolic extract of the aerial part of L. virginicum exhibited the strongest antimicrobial activity, and it could be potential candidate specie for the development of novel veterinary drugs with low cost and fewer side effects.


O presente estudo teve como objetivo investigar a eficácia de plantas antibacterianas tradicionalmente usadas (Euphorbia prostrata, Schinus molle, Brickellia veronicaefolia e Lepidium virginicum) na cordilheira Santa Rosa, em Guanajuato, contra os principais patógenos causadores de mastite. As plantas selecionadas foram rastreadas fitoquimicamente quanto a alcalóides, flavonóides, polifenóis, saponinas, antraquinona, glicosídeos cardíacos, esteróides e terpenóides. Além disso, para atingir o objetivo principal da presente pesquisa, extratos de plantas selecionadas foram testados quanto à atividade antibacteriana in vitrocontra Staphylococcus aureus, Escherichia coli, Shigella spp., Bacillus subtilis, Clavibacter spp., Proteus vulgaris e Salmonella spp. Todas essas bactérias foram isoladas de mastite clínica em vacas leiteiras. Os resultados indicaram que o extrato etanólico da parte aérea de L. virginicum exibia a atividade antimicrobiana mais forte e poderia ser uma espécie potencial candidata ao desenvolvimento de novos medicamentos veterinários com baixo custo e menos efeitos colaterais.


Assuntos
Schinus molle , Lepidium , Euphorbia , Mastite Bovina , Medicina Tradicional , Antibacterianos
6.
Medicina (B.Aires) ; 68(6): 433-436, nov.-dic. 2008. tab
Artigo em Espanhol | LILACS | ID: lil-633583

RESUMO

No existe estudio que evalúe el estado de la oxigenoterapia en vuelo (OV) en nuestro país. El objetivo de este estudio fue evaluar los requisitos, dificultades, sistemas y costos de la OV de las companías aéreas nacionales (N) e internacionales (I) que operan desde Buenos Aires. Se utilizó la misma encuesta telefónica y metodología que el estudio de Stoller y col.12. Los autores se comunicaron telefónicamente con 25 aerolíneas que operaban en los dos aeropuertos de Buenos Aires en julio de 2007, y se interrogó sobre los requisitos necesarios para viajar, sistemas y costos. Se usaron técnicas estadísticas convencionales siendo significativa p<0.05. De 25 aerolíneas, se descartaron seis (24%) por falta de información (60% de las N y 16% de las I). El 100% de las N permitían la OV vs. 80% de las I (p<0.05). El 100% de las N y 94% de las I exigían certificado médico (p=NS). El 71% de las N requerían de aviso previo vs. 100% de las I (p<0.05). El 50% de las N proveían interfases de administración de oxígeno vs. 87% de las I (p=NS). El 100% de las N disponían del oxígeno sin cargo, vs. 50% de las I (p=NS). El costo oscilaba entre 70 a 300 dólares por escala. En conclusión, se observó una marcada dificultad en la provisión de información de las compañías aéreas, y restricciones de su uso. El costo es muy variable y se da principalmente en las compañías aéreas I. Consideramos necesario implementar acciones que faciliten el acceso de los pacientes y médicos a la información pertinente de cada compañía aérea sobre OV.


There are no data about supplemental oxygen in flight in our country. The objective of our study was to evaluate arranging in-flight-oxygen required by a simulated traveler, system of administration and costs, and to compare the results between Argentine-based (A) and international (I) airlines. The questionnaire used was similar to that of Stoller et al12. Data collection consisted of telephone calls placed by one of the authors to all commercial air carriers listed in our two Buenos Aires City airports during July 2007. A structured interview with questions was addressed on issues that an oxygen-using air traveler would need to arrange in-flight oxygen. Of the 25 airlines, 6 were discarded because of lack of information (24%, three A -60%-and one I-16%-). All A allowed in-flightoxygen vs. 80% of I (p<0.05), 100% of A and 94% of I required a medical certificate (p=NS); 71% of A and 100% of I required previous notification (p<0.05); 50% of A and 87% of I provided patient interphases of oxygen administration (p=NS). Free of charge oxygen could be provided by 100% of A and 50% of I, with airline charge between 70 to 300 dollars. In conclusion, we observed different policies, rules, availability, and a pronounced lack of standardization of airline information. The cost of oxygen was very different between airlines and it was superior on I. It will be necessary to carry out actions to facilitate patient access to oxygentherapy and to standardize medical information among airlines in our country.


Assuntos
Humanos , Aeronaves , Medicina Aeroespacial/instrumentação , Oxigenoterapia/instrumentação , Viagem , Argentina , Custos e Análise de Custo , Oxigenoterapia/economia , Oxigenoterapia/normas , Simulação de Ambiente Espacial
7.
Hippocampus ; 14(4): 526-35, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15224987

RESUMO

The interleukin-1 (IL-1) cytokine family (IL-1alpha, IL-beta, and the IL-1 receptor antagonist) is involved in immune and inflammatory responses both in the brain and in the periphery. Recently, it has also been shown to influence behavior and memory consolidation. However, within the experimental systems studied, it has remained unclear whether the role of IL-1beta is associated solely with a pathophysiological process or whether it is a neuromodulator in normal adult brain. To evaluate the involvement of the nonpathological endogenous IL-1 system in learning, we studied the expression of IL-1alpha, IL-1beta, and IL-1ra during memory consolidation. We observed a learning-specific hippocampal IL-1alpha mRNA induction, but not that of IL-1beta or IL-1ra mRNAs, after inhibitory avoidance training. Moreover, when IL-1 receptor activity was inhibited using an adenoviral vector that expresses the IL-1 receptor antagonist (IL-1ra) in the hippocampus, both short-term and long-term memory retention scores were facilitated. In contrast, endogenous hippocampal IL-1 played no role in the habituation to a novel environment. These results demonstrate that endogenous hippocampal IL-1 specifically modulates a fear-motivated learning task, and suggest that IL-1alpha activity in the CNS is part of the hippocampal memory processing.


Assuntos
Hipocampo/imunologia , Interleucina-1/genética , Aprendizagem/fisiologia , Memória/fisiologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Habituação Psicofisiológica , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-1/antagonistas & inibidores , Masculino , Memória/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Wistar , Receptores de Interleucina-1/antagonistas & inibidores , Receptores de Interleucina-1/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sialoglicoproteínas/genética , Vocalização Animal
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