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1.
J Vector Borne Dis ; 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38238795

RESUMO

BACKGROUND OBJECTIVES: Sand flies are insects vector associated with terrestrial forest ecosystems; in the Ecuadorian Andes, they participate in the transmission of human cutaneous leishmaniasis. This geographical area is an opportunity to evaluate the role of sand flies as bioindicators od the degree of intervention of a tropical humid forest ecosystems (THF) associated with changes in the ecology of the local landscape. METHODS: CDC-light traps were used for collecting adults' sand flies in February 2020 in a humid tropical forest within Choco Biosphere Reserve. All species were identified using morphological keys. Analysis data about abundance, richness, species accumulation, diversity index, species composition communities, species sex proportion, spatial sand flies environmental, Renyi's Diversity Profile were performed to compare six spatial habitats in Mashpi locality, Ecuador. RESULTS: Sand flies were collected (n-1435); the main species are represented by Th. reburra Ny. trapidoi, Pa. aclydifera, Py. panamensis and Lu. hartmanni. Only Th. reburra is associated with not intervened forest, while the other 3 species are associated with intervened forest within Mashpi in the Choco Biosphere Reserve. The secondary forest has the major sandflies' richness, while the primary forest exhibits the major abundance. INTERPRETATION CONCLUSION: The results indicated that Th. reburra is a sandfly restricted to the Andean Forest and is a bioindicator of the high environmental health quality of the forest, while Ny. trapidoi and Pa. aclydifera are bioindicators of environmental disturbances in the forest. Additionally, Ps. panamensis, Lu. hartmanni and Ny. trapidoi are bioindicators of human impact and the risk of leishmaniasis.

2.
Methods Mol Biol ; 2660: 187-206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37191798

RESUMO

Single-cell secretion studies find important applications in molecular diagnostics, therapeutic target identification, and basic biology research. One increasingly important area of research is non-genetic cellular heterogeneity, a phenomenon that can be studied by assessing secretion of soluble effector proteins from single cells. This is particularly impactful for immune cells, as secreted proteins such as cytokines, chemokines, and growth factors are the gold standard for identifying phenotype. Current methods that rely upon immunofluorescence suffer from low detection sensitivity, requiring thousands of molecules to be secreted per cell. We have developed a quantum dot (QD)-based single-cell secretion analysis platform that can be used in different sandwich immunoassay formats to dramatically lower detection threshold, such that only one to a few molecules need be secreted per cell. We have also expanded this work to include multiplexing capabilities for different cytokines and employed this platform to study macrophage polarization under different stimuli at the single-cell level.


Assuntos
Pontos Quânticos , Citocinas , Imunoensaio/métodos
3.
NPJ Vaccines ; 7(1): 38, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35301331

RESUMO

Oropouche virus (OROV) is an arthropod-borne orthobunyavirus found in South America and causes Oropouche fever, a febrile infection similar to dengue. It is the second most prevalent arthropod-borne viral disease in South America after dengue. Over 500,000 cases have been diagnosed since the virus was first discovered in 1955; however, this is likely a significant underestimate given the limited availability of diagnostics. No fatalities have been reported to date, however, up to 60% of cases have a recurrent phase of disease within one month of recovery from the primary disease course. The main arthropod vector is the biting midge Culicoides paraensis, which has a geographic range as far north as the United States and demonstrates the potential for OROV to geographically expand. The transmission cycle is incompletely understood and vertebrate hosts include both non-human primates and birds further supporting the potential ability of the virus to spread. A number of candidate antivirals have been evaluated against OROV in vitro but none showed antiviral activity. Surprisingly, there is only one report in the literature on candidate vaccines. We suggest that OROV is an undervalued pathogen much like chikungunya, Schmallenberg, and Zika viruses were before they emerged. Overall, OROV is an important emerging disease that has been under-investigated and has the potential to cause large epidemics in the future. Further research, in particular candidate vaccines, is needed for this important pathogen.

4.
Anal Chem ; 94(2): 658-668, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34936345

RESUMO

Monitoring the secretion of proteins from single cells can provide important insights into how cells respond to their microenvironment. This is particularly true for immune cells, which can exhibit a large degree of response heterogeneity. Microfabricated well arrays provide a powerful and versatile method to assess the secretion of cytokines, chemokines, and growth factors from single cells, but detection sensitivity has been limited to high levels on the order of 10,000 per cell. Recently, we reported a quantum dot-based immunoassay that lowered the detection limit for the cytokine TNF-α to concentrations to nearly the single-cell level. Here, we adapted this detection method to three additional targets while maintaining high detection sensitivity. Specifically, we detected MCP-1, TGF-ß, IL-10, and TNF-α using quantum dots with different emission spectra, each of which displayed a detection threshold in the range of 1-10 fM or ∼1-2 molecules per well. We then quantified secretion of all four proteins from single macrophage cells that were stimulated toward a pro-inflammatory state with lipopolysaccharide (LPS) or toward a pro-healing state with both LPS and interleukin 4 (IL-4). We found that MCP-1 and TGF-ß were predominantly secreted at high levels only (>10,000 molecules/cell), while a substantial number of cells secreted IL-10 and TNF-α at lower levels that could only be detected using our method. Subsequent principal component and cluster analysis revealed that secretion profiles could be classified as either exclusively pro-inflammatory, including MCP-1 and/or TNF-α, or more subtle responses displaying both pro-healing and pro-inflammatory characters. Our results highlight the heterogeneous and nondiscrete nature of macrophage phenotypes following in vitro stimulation of a cell line. Future work will focus on expanding the multiplexing capacity by extending emission spectra bandwidth and/or spatially barcoding capture antibodies, as well as evaluating the enhanced detection sensitivity capabilities with normal and diseased immune cell populations in vitro and in vivo.


Assuntos
Citocinas , Fator de Necrose Tumoral alfa , Citocinas/análise , Imunoensaio/métodos , Lipopolissacarídeos/farmacologia , Macrófagos/química , Fator de Necrose Tumoral alfa/análise
5.
Biomimetics (Basel) ; 6(2)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34069181

RESUMO

The prediction of leaf wetness duration (LWD) is an issue of interest for disease prevention in coffee plantations, forests, and other crops. This study analyzed different LWD prediction approaches using machine learning and meteorological and temporal variables as the models' input. The information was collected through meteorological stations placed in coffee plantations in six different regions of Costa Rica, and the leaf wetness duration was measured by sensors installed in the same regions. The best prediction models had a mean absolute error of around 60 min per day. Our results demonstrate that for LWD modeling, it is not convenient to aggregate records at a daily level. The model performance was better when the records were collected at intervals of 15 min instead of 30 min.

6.
Analyst ; 144(3): 980-989, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30270391

RESUMO

Single cell analysis methods are increasingly being utilized to investigate how individual cells process information and respond to diverse stimuli. Soluble proteins play a critical role in controlling cell populations and tissues, but directly monitoring secretion is technically challenging. Microfabricated well arrays have been developed to assess secretion at the single cell level, but these systems are limited by low detection sensitivity. Semiconductor quantum dots (QD) exhibit remarkably bright and photostable luminescence signal, but to date they have not been evaluated in single cell secretion studies using microfabricated well arrays. Here, we used QDs in a sandwich immunoassay to detect secretion of the soluble cytokine tumor necrosis factor-α (TNF-α) from single cells. To enhance detection sensitivity, we employed two different strategies. First, we used a unique single QD imaging approach, which provided a detection threshold (180 attomolar) that was >100-fold lower than previously reported results using QDs. We also amplified QD binding to each captured TNF-α molecule using the bioorthogonal cycloaddition reaction between trans-cyclooctene and tetrazine, which further lowered detection threshold to 60 attomolar. This is 6 orders of magnitude more sensitive than organic fluorophores that have been used for single cell secretion studies, and far surpasses single molecule resolution within sub-picoliter microwells that are used to assess single cell secretion. Finally, single cell secretion studies were performed using phorbol 12-myristate 13-acetate (PMA) differentiated and lipopolysaccharide (LPS) activated U-937 cells. TNF-α secretion was detected from 3-fold more single cells using the QD-based method in comparison to rhodamine, which was accomplished by extending sensitivity into the range of ∼2 to 10 000 molecules captured per microwell. In future work, we will apply this technique to assess immune cell secretion dynamics under diverse stimuli and disease settings. We will also incorporate multiplexing capabilities to evaluate the secretome at the resolution of single molecules.


Assuntos
Imunoensaio/métodos , Pontos Quânticos , Análise de Célula Única/métodos , Fator de Necrose Tumoral alfa/análise , Humanos , Limite de Detecção , Células U937
7.
Int J Health Policy Manag ; 6(9): 501-508, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28949462

RESUMO

BACKGROUND: Mental, neurological, and substance (MNS) use disorders are a leading cause of disability worldwide; specifically in Peru, MNS affect 1 in 5 persons. However, the great majority of people suffering from these disorders do not access care, thereby making necessary the improvement of existing conditions including a major rearranging of current health system structures beyond care delivery strategies. This paper reviews and examines recent developments in mental health policies in Peru, presenting an overview of the initiatives currently being introduced and the main implementation challenges they face. METHODS: Key documents issued by Peruvian governmental entities regarding mental health were reviewed to identify and describe the path that led to the beginning of the reform; how the ongoing reform is taking place; and, the plan and scope for scale-up. RESULTS: Since 2004, mental health has gained importance in policies and regulations, resulting in the promotion of a mental health reform within the national healthcare system. These efforts crystallized in 2012 with the passing of Law 29889 which introduced several changes to the delivery of mental healthcare, including a restructuring of mental health service delivery to occur at the primary and secondary care levels and the introduction of supporting services to aid in patient recovery and reintegration into society. In addition, a performance-based budget was approved to guarantee the implementation of these changes. Some of the main challenges faced by this reform are related to the diversity of the implementation settings, eg, isolated rural areas, and the limitations of the existing specialized mental health institutes to substantially grow in parallel to the scaling-up efforts in order to be able to provide training and clinical support to every region of Peru. CONCLUSION: Although the true success of the mental healthcare reform will be determined in the coming years, thus far, Peru has achieved a number of legal, policy and fiscal milestones, thereby presenting a unique and fertile environment for the expansion of mental health services.


Assuntos
Reforma dos Serviços de Saúde/organização & administração , Serviços de Saúde Mental/organização & administração , Fortalecimento Institucional/organização & administração , Política de Saúde , Humanos , Transtornos Mentais/terapia , Peru , Melhoria de Qualidade/organização & administração
9.
Rev. biol. trop ; 63(supl.1): 407-416, abr. 2015. graf
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-958151

RESUMO

Resumen Se efectuó una evaluación geomorfológica y de zonas de erosión y sedimentación del sector oeste de la Península, desde punta Banco hasta punta El Mangle, con el fin de determinar aspectos relevantes desde el punto de vista geológico. El estudio se llevo a cabo durante 9 días en enero del 2008, tiempo en el cual, se realizó el estudio geológico, geomorfológico y de zonas de erosión-sedimentación costera, presentándose en este trabajo solamente los resultados relevantes de los últimos dos aspectos. Geomorfológicamente, se reconocen una predominancia de morfologías de origen estructural, y en menor grado de origen marino, fluvial y denudacional. Se definieron cuatro zonas de erosión-sedimentación, zonas de erosión intensa, de erosión moderada a leve, de erosión y sedimentación y zonas de depositación. Los procesos geológicos más importantes son los deslizamientos, la erosión costera y la alta sismicidad del área, factores que deben ser tomados en cuenta para una adecuada planificación rural de la península


Abstract The present work describes a geomorpholopic evaluation of the Burica peninsula, during 9 days in January 2008. Coastal geomorphology, erosion and depositional zones were evaluated between punta Banco and punta El Mangle. The most important morphologies found were structural origin morphologies, represented by active tectonic deformation, produced by the Panamá Fracture Zone, and the subduction of the Cocos ridge. The structural origin morphologies identified were, structural-denudational zones which dominate the study area, homocline in the south of the peninsula and structural terraces, that are observed easily between punta El Mangle and La Peña, and in punta Banco. Other morphologies were identified, such as marine, fluvial and denudational morphologies. The marine-origin morphologies include the beach, subdivided in subareas, separated due to the waves dynamic, the cliffs, that dominate the area between La Peña river and punta Banco, and the shore platforms in the area between punta El Mangle and La Peña. The denudational morphology is represented by landslides, which area present mainly in the cliffs. In the other hand, the fluvial origin morphologies, include La Peña, Peñita, Caña Blanca and Coco mouths and the floodplain of La Peña river. Intense erosional, slight to moderate erosional, sedimentational, and erosion and sedimentational zones were identified, having a great importance the coastal erosion, especially observed in the central and south of the peninsula. Considering the results and the interaction of them, the main hazards found are landslides, coastal erosion and the high seismicity of the area, which should be taken into account and studied in detail for a proper planning of the rural development. Rev. Biol. Trop. 63 (Suppl. 1): 407-416. Epub 2015 April 01.


Assuntos
Acidentes Geográficos/classificação , Geomorfologia , Geologia , Costa Rica
10.
Biomaterials ; 35(35): 9554-61, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25154663

RESUMO

Oncolytic viruses (OVs) constitute a promising class of cancer therapeutics which exploit validated genetic pathways known to be deregulated in many cancers. To overcome an immune response and to enhance its potential use to treat primary and metastatic tumors, a method for liposomal encapsulation of adenovirus has been developed. The encapsulation of adenovirus in non-toxic anionic lecithin-cholesterol-PEG liposomes ranging from 140 to 180 nm in diameter have been prepared by self-assembly around the viral capsid. The encapsulated viruses retain their ability to infect cancer cells. Furthermore, an immunoprecipitation (IP) technique has shown to be a fast and effective method to extract non-encapsulated viruses and homogenize the liposomes remaining in solution. 78% of adenovirus plaque forming units were encapsulated and retained infectivity after IP processing. Additionally, encapsulated viruses have shown enhanced transfection efficiency up to 4 × higher compared to non-encapsulated Ads. Extracting non-encapsulated viruses from solution may prevent an adverse in vivo immune response and may enhance treatment for multiple administrations.


Assuntos
Adenoviridae/isolamento & purificação , Lecitinas/química , Lipossomos/química , Adenoviridae/classificação , Animais , Linhagem Celular Tumoral , Terapia Genética/métodos , Células HEK293 , Humanos , Imunoprecipitação , Camundongos , Camundongos da Linhagem 129 , Terapia Viral Oncolítica , Transfecção
11.
Rev. venez. cir ; 67(3): 99-103, 2014. tab, graf
Artigo em Espanhol | LIVECS, LILACS | ID: biblio-1401200

RESUMO

Objetivo: Los pacientes quirúrgicos constituyen una de las poblaciones más vulnerables para contraer infecciones nosocomiales (particularmente del sitio quirúrgico). La higiene de manos es fundamental para reducir la transmisión de infecciones, es por esto que nos parece necesario evaluar el cumplimiento del protocolo de higiene de manos (propuesto por la Organización Mundial de la Salud) en servicios quirúrgicos de un hospital modelo en Caracas. Métodos: Se llevó a cabo un estudio descriptivo, transversal, observacional, para evaluar el cumplimiento del protocolo y la disponibilidad de requisitos mínimos necesarios para llevarlo a cabo. Se utilizaron métodos de estadística descriptiva para el análisis de datos. Para la proporción de individuos que cumplieron el protocolo, se calcularon intervalos de confianza de 95% y al comparar el personal médico y el de enfermería se utilizó la prueba de chi-cuadrado. Resultados: Solo 4 habitaciones de pacientes (8,5%), contaban con los requisitos mínimos para un adecuado cumplimiento del protocolo. Por otra parte, solo el 2,3% de los participantes (pT = 0,0227. IC95%: 0,00 ; 0,0667) lo llevó a cabo. El personal de enfermería presentó una diferencia de riesgo de 0,033 (-0,097;0,031, p=0,51) con respecto al médico. Conclusión: La falta de prácticas de higiene de manos en la institución de salud (97,7%), es un problema que debe ser más estudiado. Es posible que se deba al hecho de que 91,5% de las habitaciones no cumple con los requisitos mínimos necesarios para el lavado de manos, sin embargo queda fuera de los alcances de este estudio explicar la causa(AU)


Objective: Surgical patients constitute one of the most vulnerable populations to nosocomial infections (particularly surgical site infections). Hand hygiene is fundamental to reduce infection transmission. This is the reason why we consider necessary to evaluate the fulfillment of the hand hygiene protocol (established by the World Health Organization) in surgical departments of a model healthcare center in Caracas. Methods: We carried out a crosssectional study in order to evaluate the fulfillment of the aforementioned protocol, as well as the availability of minimum requirements to perform it. We used descriptive statistics for data analysis, then constructed 95% confidence intervals for the proportion of individuals who carried out the protocol during daily activities, in order to compare nursing staff to medical staff we used the chisquare hypothesis test. Results: Only 4 patient rooms (8.5%) had the minimum requirements to fulfill an adequate hand hygiene protocol. On the other hand, only 2.3% of the individuals observed actually performed hand hygiene (pT= 0.0227. 95%CI: 0.00; 0.0667). Nursing staff had a non-statistically-significant risk difference of 0.033 (-0.097;0.031, p=0.51) when compared to medical staff. Conclusion: Absence of hand hygiene practices in the healthcare center (97.7%) is an issue that has to be studied more profoundly. It is indeed possible that this non adherence to the protocol is due to the fact that 91.5% of the patient rooms did not have the minimum requirements to perform adequate hand hygiene, it is however outside the scope of the study to establish any causal relations(AU)


Assuntos
Infecção da Ferida Cirúrgica , Organização Mundial da Saúde , Desinfecção das Mãos , Infecção Hospitalar , Transmissão de Doença Infecciosa , Recursos Humanos de Enfermagem
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