593 research outputs found
Expression of MICA, MICB and NKG2D in human leukemic myelomonocytic and cervical cancer cells
<p>Abstract</p> <p>Background</p> <p>Cancer cells are known to secrete the stress molecules MICA and MICB that activate cytotoxicity by lymphocytes and NK cells through their NKG2D receptor as a mechanism of immunological defense. This work was undertaken to evaluate if cancer cells can also express this receptor as a possible mechanisms of depletion of MIC molecules and thus interfere with their immune recognition.</p> <p>Methods</p> <p>Myelomonocytic leukemic (TPH-1 and U-937) and cervical cancer (CALO and INBL) cell lines were evaluated by Western Blot, ELISA, flow cytometry and immunocytochemistry to evaluate their capacity to express and secrete MICA and MICB and to be induced to proliferate by these molecules as well as to express their receptor NKG2D. Statistical analysis was performed by two-way ANOVA for time course analysis and Student's t-test for comparison between groups. Values were considered significantly different if p < 0.05.</p> <p>Results</p> <p>THP-1 and U-937 produce and secrete the stress MICA and MICB as shown by Western Blot of lysed cells and by ELISA of their conditioned media. By Western Blot and flow cytometry we found that these cells also express the receptor NKG2D. When THP-1 and U-937 were cultured with recombinant MICA and MICB they exhibited a dose dependent induction for their proliferation. CALO and INBL also produce MICA and MICB and were induced to proliferate by these stress molecules. By Western Blot, flow cytometry and immunocytochemistry we also found that these cells express NKG2D.</p> <p>Conclusions</p> <p>Our novel results that tumor cells can simultaneously secrete MIC molecules and express their receptor, and to be induced for proliferation by these stress molecules, and that tumor epithelial cells can also express the NKG2D receptor that was thought to be exclusive of NK and cytotoxic lymphocytes is discussed as a possible mechanism of immunological escape and of tumor growth induction.</p
PRIVATE SAVINGS IN TRANSITION ECONOMIES: ARE THERE TERMS OF TRADE SHOCKS?
The paper examines the impact of terms of trade shocks on private savings in the transition economies after accounting for the effect of other determinants. Economic agents in the transition economies are subject to tight credit constraints which are more pronounced during bad state of nature. Thus, adverse shocks to commodity prices in the world market can force them to reduce savings by a larger amount than they would otherwise have. Empirical analysis using a dynamic panel model and data from twenty one transition economies confirm that most of the determinants of savings identified in the literature also apply to the transition economies. Favorable movements in both the permanent and transitory components of the terms of trade have a significant positive impact on private savings with transitory movements having a larger impact than the permanent component. This reflects the lack of access to foreign borrowing that many of the transition economies have faced during the last decade. Although the impact of terms of trade shocks are found to be asymmetric, the magnitude of the impact appears to be small. The results are robust for alternative estimators, determinants, and country groupings.http://deepblue.lib.umich.edu/bitstream/2027.42/39958/3/wp572.pd
Closure of a large lumbosacral myelomeningocele post operative defect with a human cadaveric split-thickness skin graft: a case report
Spina bifida is the most common birth defect of the central nervous system that is compatible with life, and myelomeningocele represents its most frequent form. Congenital myelomeningocele (CMM) has a worldwide incidence of 0.5 to 0.8 per 1,000 live newborns. CMM is a complex condition resulting from incomplete closure of the neural tube, mainly in the lumbosacral region. The objective of the surgical repair of the CMM is the reconstruction of all the tissue layers of the defect, avoiding possible postoperative complications. The aim of this case review is to present a re-epithelialization closure in a patient with a large CMM defect in who primary hermetic closure was not possible because there was too much tension at the edges of the defect. Therefore, human cadaveric split-thickness skin grafts were placed over the dura mater and the aponeurotic layer, covering the entire defect and an adequate healing and completely closure of the defect were observed in eight weeks. The surgical management of large meningomyelocele defects represents a major challenge and no single protocol exists for its reconstruction. The repair of an MMC defect should be performed during the first 72 hours after birth. After neurosurgical closure of the neural tube and dura, the myelomeningocele defect requires good quality skin and subcutaneous tissue with minimal wound tension for stable coverage. Human cadaveric skin grafts are considered a useful technique for temporary wound coverage because they lead to a more natural healing environment, possess ideal properties, and provide a physiological barrier that reduces microbiological contamination, in addition, it acts as a bridge to adhere to and to seal wound beds
Acoustically Levitated Whispering-Gallery Mode Microlasers
Acoustic levitation has become a crucial technique for contactless manipulation in several fields, particularly in biological applications. However, its application in the photonics field remains largely unexplored. In this study, we implement an affordable and innovative phased-array levitator that enables stable trapping in the air of micrometer dye-doped droplets, thereby enabling the creation of microlasers. For the first time, this paper presents a detailed performance of the levitated microlaser cavity, supported by theoretical analysis concerning the hybrid technology based on the combination of whispering-gallery modes and acoustic fields. The pressure field distribution inside the acoustic cavity is numerically solved and qualitatively matched with the schlieren deflectometry technique. The optical lasing features of the levitated microlasers are highly comparable with those devices based On-a-Chip registering maximum Q-factors of ~ 105, and minimum lasing thresholds ~ 150 nJ cm−2. The emission comb is explained as a sum of multiple individual-supported whispering-gallery modes. The use of novel touchless micrometric lasers, produced with an acoustic levitator brings new technological opportunities based on photonic-acoustic technological platforms
Propuestas estrat?gicas que promuevan el relanzamiento de la Zona Especial de Desarrollo Paita, 2021-2022
En el presente trabajo de tesis se enfoca en brindar propuestas estrat?gicas que promuevan el relanzamiento de la zona especial de desarrollo (ZED) Paita 2021-2022 la cual se encuentra en el Departamento de Piura en la zona norte del Per?. Como objetivo principal se plantea establecer estrategias que promuevan el relanzamiento de la Zona especial de desarrollo Paita para atraer al empresario nacional y extranjero dentro de la ZED con el fin de impulsar la instalaci?n de empresas privadas nacionales e internacionales permitiendo el crecimiento de la econom?a de la regi?n. La finalidad del trabajo es incentivar y promover el uso de la ZED Paita a trav?s de diversas estrategias tomando como ejemplo los casos de ?xito de otras ZED en otros pa?ses c?mo (China, M?xico, entre otros) debido a que las ZED suman valor a las econom?as ayudando a su crecimiento y desarrollo. Para poder establecer las estrategias se elabor? una encuesta a las empresas instaladas dentro de la ZED y se llevaron a cabo entrevistas a expertos y empresarios fuera de la ZED con el fin de realizar un an?lisis e interpretaci?n de los resultados y definir las propuestas estrat?gicas que promuevan el relanzamiento de la ZED Paita
The biological applications of IPN hydrogels
Background and purpose: Interpenetrating polymer network (IPN) hydrogels are an adaptable category of materials, exhibiting remarkable promise for various biological applications due to their distinctive structural and functional attributes. This review delves into the synthesis of IPN hydrogels through both physical and chemical methodologies, elucidating how these techniques allow for precise tailoring of mechanical properties, swelling behaviour, and biocompatibility. Experimental approach: We conducted an extensive literature review by searching well-established online research databases for articles published since 2009 to gather comprehensive data on IPN hydrogels. Key results: Our review highlights several critical applications of IPN hydrogels in the biomedical field; i) Tissue engineering: IPN hydrogels are evaluated for their capacity to emulate the extracellular matrix, making them excellent scaffolds for tissue engineering; ii) Controlled drug release: The ability of IPN hydrogels to modulate drug release rates and protect bioactive molecules is explored. Their structure enables sustained and targeted delivery of therapeutic agents, enhancing treatment efficacy; iii) 3D bioprinting: The use of IPN hydrogels as bioinks for 3D bioprinting is assessed, demonstrating their capability to construct intricate, biomimetic structures with high precision; and iv) Regenerative medicine: the development of biomimetic IPN hydrogels for regenerative medicine, emphasizing their potential to closely replicate natural biological environments, thereby promoting effective tissue repair and regeneration. Conclusion: IPN hydrogels emerge as a versatile and multifaceted platform with significant implications for advancing biomedical science and clinical therapies. Their diverse applications highlight their potential to revolutionize current biomedical practices and contribute to the development of innovative therapeutic solutions
Stevens-Johnson syndrome and toxic epidermal necrolysis: a review
Stevens Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are considered a single entity with variability in the extent of the lesions, characterized by erythema multiforme that may involve mucosa. Severe cutaneous reactions secondary to medications are classified according to the area of epidermal detachment. The activation of cytotoxic T cells and macrophages is mediated mainly by IL-2 and interferon gamma secreted by Th1 lymphocytes, and the activation of eosinophils and B lymphocytes in IgE is mediated by secreted IL-4, IL-5, IL-10 and IL13 by B lymphocytes. The topography of SJS is predominantly central, affecting the trunk and sometimes a generalized dissemination is shown that affects a body surface area of less than 10%, characterized by irregular violaceous erythematous macules of target shooting, which can form confluent blisters. TEN is characterized by a skin detachment greater than 30% of the body surface, whose predominant lesion is diffuse erythema with individual macules, which give rise to detachment surfaces greater than 5 cm. The treatment is symptomatic, nonspecific, and aimed at avoiding complications, carried out in specialized intensive care units, due to ignorance of the pathogenesis. Integral management with different therapeutic alternatives can represent a crucial part in the multisystemic management of SJS and TEN
Diagnóstico de producción en ganado lechero en pastoreo de un grupo ganadero de validación y transferencia de tecnología
The regionalization of framing issues for producers Livestock Group of Validation and Technology Transfer (GGAVATT) from San Jose Miahuatlán Veracruz, Mexico, under the current production of native grass prairie with mainly during the months of higher temperature have a poor performance and thus milk production declines which promotes a great use of concentrated feeds which causes an increase in production cost and less use to them. For this purpose we made a diagnosis of current conditions GGAVATT production, yielding information that helps us source and compared to determine precisely what the effect of applying the proposed alternative. We propose an alternative implementation of pastures with improved pastures needed to produce a greater amount of forage per unit area especially in the colder months.La regionalización de la problemática encuadrando a los productores del Grupo Ganadero de Validación y Transferencia de Tecnología (GGAVATT) de San José Miahuatlán Veracruz, México, bajo la actual situación de producción de praderas básicamente con gramas nativas que durante los meses de menor frío tienen un pobre desempeño y por ende la producción de leche se deteriora lo cual promueve una gran utilización de alimentos concentrados lo que provoca un incremento en el costo de producción y una menor utilidad para estos. Para dicho propósito se realizó un diagnóstico de las condiciones actuales de producción del GGAVATT, arrojando información que nos sirve de partida y de comparación para determinar con precisión cuál es el efecto de aplicar la alternativa propuesta. Se plantea como alternativa la implantación de praderas con pastos mejorados que permitan producir una mayor cantidad de forrajes por unidad de superficie sobre todo en los meses de menor temperatura
Effect of graphene oxide on bacteria and peripheral blood mononuclear cells
"Background Driven by the potential biological applications of graphene, many groups have studied the response of cells exposed to graphene oxide (GO). In particular, investigations of bacteria indicate that there are 2 crucial parameters, which so far have only been investigated separately: GO size and exposure methodology. Our study took into account both parameters. We carefully characterized the samples to catalog sizes and structural properties, and tested different exposure methodologies: exposure in saline solution and in the presence of growth media. Furthermore, we performed experiments with peripheral blood mononuclear cells exposed to our GO materials. Methods Atomic force microscopy, scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and transmission electron microscopy were used to characterize the morphology and composition of different samples of GO: GO-H2O, GO-PBS and GO-MG. Our samples had 2D sizes of ?100 nm (GO-H2O and GO-PBS) and >2 µm (GO-MG). We tested antibacterial activity and cytotoxicity toward peripheral blood mononuclear cells of 3 different GO samples. Results A size-dependent growth inhibition of Escherichia coli (DH5 ?) in suspension was found, which proved that this effect depends strongly on the protocol followed for exposure. Hemocompatibility was confirmed by exposing peripheral blood mononuclear cells to materials for 24 hours; viability and apoptosis tests were also carried out. Conclusions Our experiments provide vital information for future applications of GO in suspension. If its antibacterial properties are to be potentiated, care should be taken to select 2D sizes in the micrometer range, and exposure should not be carried out in the presence of grow media.
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