Integration of complementary split-ring resonators into digital microfluidics for manipulation and direct sensing of droplet composition.

This paper demonstrates the integration of complementary split-ring resonators (CSSRs) with digital microfluidics (DMF) sample manipulation for passive, on-chip radio-frequency (RF) sensing. Integration is accomplished by having the DMF and the RF-sensing components share the same ground plane: by designing the RF-resonant openings directly into the ground plane of a DMF device, both droplet motion and sensing are achieved, adding a new on-board detection mode for use in DMF. The system was modelled to determine basic features and to balance various factors that need to be optimized to maintain both functionalities (DMF-enabled droplet movement and RF detection) on the same chip. Simulated and experimental results show good agreement. Using a portable measurement setup, the integrated CSSR sensor was used to effectively identify a series of DMF-generated drops of ethanol-water mixtures of different compositions by measuring the resonant frequency of the CSSR. In addition, we show that a binary solvent system (ethanol/water mixtures) results in consistent changes in the measured spectrum in response to changes in concentration, indicating that the sensor can distinguish not only between pure solvents from each other, but also between mixtures of varied compositions. We anticipate that this system can be refined further to enable additional applications and detection modes for DMF systems and other portable sensing platforms alike. This proof-of-principle study demonstrates that the integrated DMF-CSSR sensor provides a new platform for monitoring and characterization of liquids with high sensitivity and low consumption of materials, and opens the way for new and exciting applications of RF sensing in microfluidics.

Digital microfluidic platform assembled into a home-made studio for sample preparation and colorimetric sensing of S-nitrosocysteine.

Digital microfluidics (DMF) is a versatile lab-on-a-chip platform that allows integration with several types of sensors and detection techniques, including colorimetric sensors. Here, we propose, for the first time, the integration of DMF chips into a mini studio containing a 3D-printed holder with previously fixed UV-LEDs to promote sample degradation on the chip surface before a complete analytical procedure involving reagent mixture, colorimetric reaction, and detection through a webcam integrated on the equipment. As a proof-of-concept, the feasibility of the integrated system was successfully through the indirect analysis of S-nitrosocysteine (CySNO) in biological samples. For this purpose, UV-LEDs were explored to perform the photolytic cleavage of CySNO, thus generating nitrite and subproducts directly on DMF chip. Nitrite was then colorimetrically detected based on a modified Griess reaction, in which reagents were prepared through a programable movement of droplets on DMF devices. The assembling and the experimental parameters were optimized, and the proposed integration exhibited a satisfactory correlation with the results acquired using a desktop scanner. Under the optimal experimental conditions, the obtained CySNO degradation to nitrite was 96%. Considering the analytical parameters, the proposed approach revealed linear behavior in the CySNO concentration range between 12.5 and 400 µmol L-1 and a limit of detection equal to 2.8 µmol L-1. Synthetic serum and human plasma samples were successfully analyzed, and the achieved results did not statistically differ from the data recorded by spectrophotometry at the confidence level of 95%, thus indicating the huge potential of the integration between DMF and mini studio to promote complete analysis of lowmolecular weight compounds.

Use of a rapid digital microfluidics-powered immunoassay for assessing measles and rubella infection and immunity in outbreak settings in the Democratic Republic of the Congo.

The Democratic Republic of the Congo (DRC) has a high measles incidence despite elimination efforts and has yet to introduce rubella vaccine. We evaluated the performance of a prototype rapid digital microfluidics powered (DMF) enzyme-linked immunoassay (ELISA) assessing measles and rubella infection, by testing for immunoglobulin M (IgM), and immunity from natural infection or vaccine, by testing immunoglobulin G (IgG), in outbreak settings. Field evaluations were conducted during September 2017, in Kinshasa province, DRC. Blood specimens were collected during an outbreak investigation of suspected measles cases and tested for measles and rubella IgM and IgG using the DMF-ELISA in the field. Simultaneously, a household serosurvey for measles and rubella IgG was conducted in a recently confirmed measles outbreak area. DMF-ELISA results were compared with reference ELISA results tested at DRC's National Public Health Laboratory and the US Centers for Disease Control and Prevention. Of 157 suspected measles cases, rubella IgM was detected in 54% while measles IgM was detected in 13%. Measles IgG-positive cases were higher among vaccinated persons (87%) than unvaccinated persons (72%). In the recent measles outbreak area, measles IgG seroprevalence was 93% overall, while rubella seroprevalence was lower for children (77%) than women (98%). Compared with reference ELISA, DMF-ELISA sensitivity and specificity were 82% and 78% for measles IgG; 88% and 89% for measles IgM; 85% and 85% for rubella IgG; and 81% and 83% for rubella IgM, respectively. Rubella infection was detected in more than half of persons meeting the suspected measles case definition during a presumed measles outbreak, suggesting substantial unrecognized rubella incidence, and highlighting the need for rubella vaccine introduction into the national schedule. The performance of the DMF-ELISA suggested that this technology can be used to develop rapid diagnostic tests for measles and rubella.

A Novel Host of an Emerging Disease: SARS-CoV-2 Infection in a Giant Anteater (Myrmecophaga tridactyla) Kept Under Clinical Care in Brazil.

A young male free-ranging giant anteater (Myrmecophaga tridactyla) was found with paralysis of pelvic limbs on a highway and kept under human care. Radiographs confirmed multiple incomplete fractures in the thoracolumbar vertebrae. Due to the poor prognosis, euthanasia was chosen. The infection was established by viral SARS-CoV-2 RNA detection in the rectal swab, spleen and kidney samples. Immunohistochemistry detected the viral nucleocapsid protein in sections of the lungs, liver, spleen, lymph nodes, and large intestine sections, and spike protein antigen in the lung tissue. Pilosa order species should be included as potential hosts of natural infection of SARS-CoV-2.

Correction to: A microfluidic platform for continuous monitoring of dopamine homeostasis in dopaminergic cells.

[This corrects the article DOI: 10.1038/s41378-019-0049-2.].

A microfluidic platform for continuous monitoring of dopamine homeostasis in dopaminergic cells.

Homeostasis of dopamine, a classical neurotransmitter, is a key indicator of neuronal health. Dysfunction in the regulation of dopamine is implicated in a long list of neurological disorders, including addiction, depression, and neurodegeneration. The existing methods used to evaluate dopamine homeostasis in vitro are inconvenient and do not allow for continuous non-destructive measurement. In response to this challenge, we introduce an integrated microfluidic system that combines dopaminergic cell culture and differentiation with electroanalytical measurements of extracellular dopamine in real-time at any point during an assay. We used the system to examine the behavior of differentiated SH-SY5Y cells upon exposure to four dopamine transporter ant/agonists (cocaine, ketamine, epigallocatechin gallate, and amphetamine) and study their pharmacokinetics. The IC50 values of cocaine, ketamine, and epigallocatechin gallate were determined to be (average ± standard deviation) 3.7 ± 1.1 µM, 51.4 ± 17.9 µM, and 2.6 ± 0.8 µM, respectively. Furthermore, we used the new system to study amphetamine-mediated dopamine release to probe the related phenomena of dopamine transporter-mediated reverse-transport and dopamine release from vesicles. We propose that this platform, which is the first platform to simultaneously evaluate uptake and release, could be useful to screen for drugs and other agents that target dopaminergic neurons and the function of the dopamine transporter. More broadly, this platform should be adaptable for any application that could benefit from high-temporal resolution electroanalysis combined with multi-day cell culture using small numbers of cells.

A Novel Osteogenic Cell Line That Differentiates Into GFP-Tagged Osteocytes and Forms Mineral With a Bone-Like Lacunocanalicular Structure.

Osteocytes, the most abundant cells in bone, were once thought to be inactive, but are now known to have multifunctional roles in bone, including in mechanotransduction, regulation of osteoblast and osteoclast function and phosphate homeostasis. Because osteocytes are embedded in a mineralized matrix and are challenging to study, there is a need for new tools and cell models to understand their biology. We have generated two clonal osteogenic cell lines, OmGFP66 and OmGFP10, by immortalization of primary bone cells from mice expressing a membrane-targeted GFP driven by the Dmp1-promoter. One of these clones, OmGFP66, has unique properties compared with previous osteogenic and osteocyte cell models and forms 3-dimensional mineralized bone-like structures, containing highly dendritic GFP-positive osteocytes, embedded in clearly defined lacunae. Confocal and electron microscopy showed that structurally and morphologically, these bone-like structures resemble bone in vivo, even mimicking the lacunocanalicular ultrastructure and 3D spacing of in vivo osteocytes. In osteogenic conditions, OmGFP66 cells express alkaline phosphatase (ALP), produce a mineralized type I collagen matrix, and constitutively express the early osteocyte marker, E11/gp38. With differentiation they express osteocyte markers, Dmp1, Phex, Mepe, Fgf23, and the mature osteocyte marker, Sost. They also express RankL, Opg, and Hif1α, and show expected osteocyte responses to PTH, including downregulation of Sost, Dmp1, and Opg and upregulation of RankL and E11/gp38. Live cell imaging revealed the dynamic process by which OmGFP66 bone-like structures form, the motile properties of embedding osteocytes and the integration of osteocyte differentiation with mineralization. The OmGFP10 clone showed an osteocyte gene expression profile similar to OmGFP66, but formed less organized bone nodule-like mineral, similar to other osteogenic cell models. Not only do these cell lines provide useful new tools for mechanistic and dynamic studies of osteocyte differentiation, function, and biomineralization, but OmGFP66 cells have the unique property of modeling osteocytes in their natural bone microenvironment. © 2019 American Society for Bone and Mineral Research.

"Plug-n-Play" Sensing with Digital Microfluidics.

Digital microfluidics (DMF) is a platform that enables highly reconfigurable and automated fluidic operations using a generic device architecture. A unique hallmark of DMF is its "flexibility": a generic device design can be used and reused for many different, divergent fluidic operations. The flexibility of DMF is compromised when devices are permanently modified with embedded sensors. Here we introduce a solution to the "flexibility gap" between fluidic operations in digital microfluidics and embedded sensors: "plug-n-play DMF" (PnP-DMF). In PnP-DMF, devices are designed to allow for rapid and seamless exchange of sensors depending on the application needs. This paper provides "proof of concept" for PnP-DMF using commercial biosensors for glucose and ß-ketone, a custom paper-based electrochemical sensor for lactate, and a generic screen-printed electroanalytical cell. We demonstrate that hot-swapping sensors between experiments allows for convenient implementation of complex processes such as automated analysis of blood samples by standard addition. Finally, we explored the suitability for using PnP sensors in tandem with other sensing modalities, combining biosensor-based electrochemical measurement of glucose with a chemiluminescent magnetic bead-based sandwich immunoassay for insulin. The latter is notable, as it constitutes the first report of an analysis of different analytes in both the supernatant and precipitate from a single sample-aliquot in a microfluidic device. The results presented here highlight the versatility of PnP-DMF, illustrating how it may be useful for a wide range of applications in diagnostics and beyond.

Degeneration of the osteocyte network in the C57BL/6 mouse model of aging.

Age-related bone loss and associated fracture risk are major problems in musculoskeletal health. Osteocytes have emerged as key regulators of bone mass and as a therapeutic target for preventing bone loss. As aging is associated with changes in the osteocyte lacunocanalicular system, we focused on the responsible cellular mechanisms in osteocytes. Bone phenotypic analysis was performed in young-(5mo) and aged-(22mo) C57BL/6 mice and changes in bone structure/geometry correlated with alterations in osteocyte parameters determined using novel multiplexed-3D-confocal imaging techniques. Age-related bone changes analogous to those in humans were observed, including increased cortical diameter, decreased cortical thickness, reduced trabecular BV/TV and cortical porosities. This was associated with a dramatic reduction in osteocyte dendrite number and cell density, particularly in females, where osteocyte dendricity decreased linearly from 5, 12, 18 to 22mo and correlated significantly with cortical bone parameters. Reduced dendricity preceded decreased osteocyte number, suggesting dendrite loss may trigger loss of viability. Age-related degeneration of osteocyte networks may impair bone anabolic responses to loading and gender differences in osteocyte cell body and lacunar fluid volumes we observed in aged mice may lead to gender-related differences in mechanosensitivity. Therapies to preserve osteocyte dendricity and viability may be beneficial for bone health in aging.

Pre-concentration by liquid intake by paper (P-CLIP): a new technique for large volumes and digital microfluidics.

Microfluidic platforms are an attractive option for incorporating complex fluid handling into low-cost and rapid diagnostic tests. A persistent challenge for microfluidics, however, is the mismatch in the "world-to-chip" interface - it is challenging to detect analytes present at low concentrations in systems that can only handle small volumes of sample. Here we describe a new technique termed pre-concentration by liquid intake by paper (P-CLIP) that addresses this mismatch, allowing digital microfluidics to interface with volumes on the order of hundreds of microliters. In P-CLIP, a virtual microchannel is generated to pass a large volume through the device; analytes captured on magnetic particles can be isolated and then resuspended into smaller volumes for further processing and analysis. We characterize this method and demonstrate its utility with an immunoassay for Plasmodium falciparum lactate dehydrogenase, a malaria biomarker, and propose that the P-CLIP strategy may be useful for a wide range of applications that are currently limited by low-abundance analytes.

Carnosine modulates nitric oxide in stimulated murine RAW 264.7 macrophages.

Excess nitric oxide (NO) production occurs in several pathological states, including neurodegeneration, ischemia, and inflammation, and is generally accompanied by increased oxidative/nitrosative stress. Carnosine [ß-alanine-histidine (ß-Ala-His)] has been reported to decrease oxidative/nitrosative stress-associated cell damage by reducing the amount of NO produced. In this study, we evaluated the effect of carnosine on NO production by murine RAW 264.7 macrophages stimulated with lipopolysaccharides + interferon-γ. Intracellular NO and intracellular and extracellular nitrite were measured by microchip electrophoresis with laser-induced fluorescence and by the Griess assay, respectively. Results showed that carnosine causes an apparent suppression of total NO production by stimulated macrophages accompanied by an unexpected simultaneous drastic increase in its intracellular low toxicity endproduct, nitrite, with no inhibition of inducible nitric oxide synthase (iNOS). ESI-MS and NMR spectroscopy in a cell-free system showed the formation of multiple adducts (at different ratios) of carnosine-NO and carnosine-nitrite, involving both constituent amino acids (ß-Ala and His) of carnosine, thus providing a possible mechanism for the changes in free NO and nitrite in the presence of carnosine. In stimulated macrophages, the addition of carnosine was also characterized by changes in the expression of macrophage activation markers and a decrease in the release of IL-6, suggesting that carnosine might alter M1/M2 macrophage ratio. These results provide evidence for previously unknown properties of carnosine that modulate the NO/nitrite ratio of stimulated macrophages. This modulation is also accompanied by changes in the release of pro-inflammatory molecules, and does not involve the inhibition of iNOS activity.

Characterization of Off-Stoichiometry Microfluidic Devices for Bioanalytical Applications.

In this paper, we further investigate the properties of off-stoichiometry thiol-ene polymers (OSTE) aiming its application in microchip electrophoresis for bioanalytical applications. The proportion of 1.3:1 (allyl:thiol) and 1:2.5 (allyl:thiol) presented the best results in terms of sealing. Raman imaging mapping of the polymers surfaces revealed an outstanding homogeneity. Water contact angle were measured as 68° ± 6° and 71° ± 5° for 1.3:1 allyl and 1:2.5 thiol, respectively. Substrates prepared with OSTE demonstrated to be less prone to sorption of nonpolar compounds. The electroosmotic flow measured for this OSTE composition was 3.8 ± 0.3·10-4 cm2 s-1 V-1, 1.5 times higher than the one found for polydimethylsiloxane microchips under the same conditions. As a proof-of-concept for the applicability of OSTE microchips in bioanalysis the immobilization of α-amylase on the polymer surface and the implementation of a Saccharomyces cerevisiae cell counter using contactless conductivity detection are demonstrated.

Indirect detection of superoxide in RAW 264.7 macrophage cells using microchip electrophoresis coupled to laser-induced fluorescence.

Superoxide, a naturally produced reactive oxygen species (ROS) in the human body, is involved in many pathological and physiological signaling processes. However, if superoxide formation is left unregulated, overproduction can lead to oxidative damage to important biomolecules, such as DNA, lipids, and proteins. Superoxide can also lead to the formation of peroxynitrite, an extremely hazardous substance, through its reaction with endogenously produced nitric oxide. Despite its importance, quantitative information regarding superoxide production is difficult to obtain due to its high reactivity and low concentrations in vivo. MitoHE, a fluorescent probe that specifically reacts with superoxide, was used in conjunction with microchip electrophoresis (ME) and laser-induced fluorescence (LIF) detection to investigate changes in superoxide production by RAW 264.7 macrophage cells following stimulation with phorbol 12-myristate 13-acetate (PMA). Stimulation was performed in the presence and absence of the superoxide dismutase (SOD) inhibitors, diethyldithiocarbamate (DDC) and 2-metoxyestradiol (2-ME). The addition of these inhibitors resulted in an increase in the amount of superoxide specific product (2-OH-MitoE(+)) from 0.08 ± 0.01 fmol (0.17 ± 0.03 mM) in native cells to 1.26 ± 0.06 fmol (2.5 ± 0.1 mM) after PMA treatment. This corresponds to an approximately 15-fold increase in intracellular concentration per cell. Furthermore, the addition of 3-morpholino-sydnonimine (SIN-1) to the cells during incubation resulted in the production of 0.061 ± 0.006 fmol (0.12 ± 0.01 mM) of 2-OH-MitoE(+) per cell on average. These results demonstrate that indirect superoxide detection coupled with the use of SOD inhibitors and a separation method is a viable method to discriminate the 2-OH-MitoE(+) signal from possible interferences.

Surface modification of PDMS microchips with poly(ethylene glycol) derivatives for µTAS applications.

In this work is presented a method for the modification of native PDMS surface in order to improve its applicability as a substrate for microfluidic devices, especially in the analysis of nonpolar analytes. Therefore, poly(ethylene glycol) divinyl ether modified PDMS substrate was obtained by surface modification of native PDMS. The modified substrate was characterized by attenuated total reflectance infrared spectroscopy, water contact angle measurements, and by evaluating the adsorption of rhodamine B and the magnitude of the EOF mobility. The reaction was confirmed by the spectroscopic evaluation. The formation of a well-spread water film over the surface immediately after the modification was an indicative of the modified surface hydrophilicity. This characteristic was maintained for approximately ten days, with a gradual return to a hydrophobic state. Fluorescence assays showed that the nonpolar adsorption property of PDMS was significantly decreased. The EOF mobility obtained was 3.6 × 10(-4) cm(2) V(-1) s(-1) , higher than the typical values found for native PDMS. Due to the better wettability promoted by the modification, the filling of the microchannels with aqueous solutions was facilitated and trapping of air bubbles was not observed.

Raman imaging spectroscopic characterization of modified poly(dimethylsiloxane) for micro total analysis systems applications.

Methacryloxypropyl-modified poly(dimethylsiloxane) rubbers were obtained from poly(dimethylsiloxane), PDMS, and methacryloxypropyltrimethoxysilane, MPTMS, by polycondensation reactions. The modified rubbers, prepared with 20 and 30% (v/v) of MPTMS, were used as substrates for microchannel fabrication by the CO(2) laser ablation technique. Raman imaging spectroscopy was used for the surface characterization, showing the homogeneity of the rubbery material, with uniform distribution of the crosslinking centers. Under the experimental conditions used, damage to the rubber from the CO(2) laser radiation used for the channel engraving was not observed. Correlation maps of the surface were obtained in order to spatially evaluate the modification inside and outside the channels. The correlations between the methacryloxypropyl-modified poly(dimethylsiloxane) rubbers and MPTMS (spectral range of 1800-1550 cm(-1)) and PDMS (spectral range of 820-670 cm(-1)) precursors were higher than 0.95 and 0.99, respectively. In addition, Raman imaging spectroscopy allows monitoring the topography of the fabricated microchannel.

Preparação, caracterização e avaliação in vitro de microesferas de bupivacaína em excesso enantiomérico de 50 por cento (S75-R25) / Preparation, characterization and in vitro evaluation of 50 percent enantiomeric excess bupivacaine (S75-R25)-loaded microspheres

JUSTIFICATIVA E OBJETIVOS: As microesferas podem ser utilizadas como um sistema de liberação controlada para prolongar a ação de anestésicos locais. Esse estudo teve como objetivo a preparação, caracterização e análise da liberação in vitro de microesferas de bupivacaína em excesso enantiomérico de 50 por cento (S75-R25). MÉTODO: As micropartículas foram preparadas utilizando o co-polímero de ácido poliláctico-co-glicólico contendo bupivacaína em excesso enantiomérico de 50 por cento pelo método spray-dryed. RESULTADOS: A caracterização das microesferas em relação ao seu tamanho e conteúdo foram similares aos valores teóricos. A liberação in vitro apresentou um padrão bifásico. CONCLUSÕES: O processo de fabricação de microesferas contendo bupivacaína em excesso enantiomérico de 50 por cento pelo método spray-dryed é factível de ser realizado, com resultados semelhantes aos encontrados com microesferas de bupivacaína.

BACKGROUND AND OBJECTIVES: Microspheres can be used as a controlled delivery system to prolong the duration of action of local anesthetics. The objective of this study was the preparation, characterization and analysis of the in vitro release of 50 percent enantiomeric excess bupivacaine (S75-R25)-loaded microspheres. METHODS: Microspheres were prepared using the copolymer of polylactide-co-glycolic acid by the spray-dryed method. RESULTS: Characterization of microspheres regarding their size and content were similar to the theoretical values. The in vitro release demonstrated a biphasic pattern. CONCLUSIONS: Manufacturing of 50 percent enantiomeric excess bupivacaine-loaded microspheres by the spray-dryed method with results similar to bupivacaine-loaded microspheres can be done.

JUSTIFICATIVA Y OBJETIVOS: Las micro esferas pueden ser utilizadas como un sistema de liberación controlada para prolongar la acción de anestésicos locales. Este estudio tuvo como objetivo la preparación, caracterización y el análisis de la liberación in vitro de micro esferas de bupivacaina en exceso enantiomérico de 50 por ciento (S75-R25). MÉTODO: Las micro partículas fueron preparadas utilizando el copolímero de ácido poliláctico-co-glicólico con bupivacaina en exceso enantiomérico de un 50 por ciento por el método spray-dryed. RESULTADOS: La caracterización de las micro esferas con relación a su tamaño y contenido fueron similares a los valores teóricos. La liberación in vitro presentó un estándar bifásico. CONCLUSIONES: El proceso de fabricación de micro esferas con bupivacaina en exceso enantiomérico de 50 por ciento por el método spray-dryed se puede realizar con resultados semejantes a los encontrados con micro esferas de bupivacaina.

Preparation, characterization and in vitro evaluation of 50% enantiomeric excess bupivacaine (S75-R25)-loaded microspheres.

BACKGROUND AND OBJECTIVES: Microspheres can be used as a controlled delivery system to prolong the duration of action of local anesthetics. The objective of this study was the preparation, characterization and analysis of the in vitro release of 50% enantiomeric excess bupivacaine (S75-R25)-loaded microspheres. METHODS: Microspheres were prepared using the copolymer of polylactide-co-glycolic acid by the spray-dryed method. RESULTS: Characterization of microspheres regarding their size and content were similar to the theoretical values. The in vitro release demonstrated a biphasic pattern. CONCLUSIONS: Manufacturing of 50% enantiomeric excess bupivacaine-loaded microspheres by the spray-dryed method with results similar to bupivacaine-loaded microspheres can be done.

[Analysis of healing in the Alba Linea with the use of Orbignya phalerata (babassu) water extract. Controlled study in rats]. / Análise da cicatrização na Linha Alba com uso de extrato aquoso de Orbignya phalerata (babaçu): estudo controlado em ratos.

INTRODUCTION: The babassu mesocarp (Orbignya phalerata) has been used in experimental research studies focused on its antiinflammatory action. In state of Maranhão--Brazil it is widely used not only as food, but also as popular medicine in wound healing process. PURPOSE: To evaluate the action of Orbignya phalerata extract in macroscopic, histologic and tensiometric aspects in the healing process of median laparotomy in rats. METHODS: Forty male adult Wistar rats were submitted to an incision in the alba linea, sutured back in one plan with separated stitches of polypropylene 5-0. After regular procedure, the animals were divided into two groups of 20 rats each. To the group named control an intraperitoneal, dose of 1.0 ml of saline solution per kilogram of body weight was done. To the experimental group, the same thing was also done, but instead of saline solution it was injected water solution of babassu, in a dose of 50 mg/kg. The animals were observed in the following days. All of them were killed within a three and seven day post-operative period schedule, and then a histological and tensiometric analysis was carried out. RESULTS: On macroscopic examination no relevant adherence, between the alba linea and the abdominal organs in the study groups, was found. Histological evaluation presented marginal significant effects (p=0.86) to acute inflammation and significant effects (p=0.003) to giant cell reaction in both control and experimental three days groups. Significant difference was observed to acute inflammation in both seven days control and experimental groups. In the intragroup analysis (control three and seven) some marginal significant effect was in relationship to acute and chronic inflammation. In the inter-experimental groups analysis, only the giant cell reactions (0.002) and colagenization had significant results. The tensiometric evaluation showed in the seven day experimental group more resistance then others. CONCLUSION: The macroscopic and histological evaluation didn't show any significant difference between the experimental and control groups, but the tensiometric evaluation at the 7th day experimental group had significant difference compared to the control group, signaling that the use of the extract of babassu intraperitoneally injected can improve the healing process.

Análise da cicatrização na Linha Alba com uso de extrato aquoso de Orbignya phalerata (babaçu). Estudo controlado em ratos / Analysis of healing in the Alba Linea with the use of Orbignya phalerata (babassu) water extract. Controlled study in rats

INTRODUÇÃO: O mesocarpo do babaçu (Orbignya phalerata) tem sido utilizado em estudos experimentais para verificar a sua ação antiinflamatória. No Maranhão, é muito utilizado como alimento e como remédio popular para cicatrização de ferimentos. OBJETIVO: Avaliar macroscópica, histológica e tensiometricamente, a ação do extrato de Orbygnia phalerata no processo de cicatrização de laparotomias medianas em ratos. MÉTODOS: Quarenta ratos da linhagem Wistar, adultos, machos, foram utilizados em procedimento experimental que consistiu em uma incisão na linha alba e síntese em plano único com pontos separados de fio de polipropileno 5-0. Após esse procedimento comum, os animais foram distribuídos em dois grupos de 20. Ao grupo chamado controle, foi utilizado injeção intraperitoneal, em dose única de 1mL de soro fisiológico para cada quilo de peso. Ao grupo experimento, utilizou-se solução aquosa de babaçu na dose de 50 mg por quilo de peso. Os animais foram acompanhados e mortos após três e sete dias, procedendo-se, a seguir, à análise tensiométrica e histológica. RESULTADOS: O exame macroscópico não mostrou presença de aderências importantes entre a linha alba e os órgãos intra-abdominais nos grupos de estudo. A avaliação histológica mostrou efeito marginalmente significativo (p=0,086) para inflamação aguda nos grupos controle e experimento de três dias e efeito significativo (p=0,003) para a reação gigantocelular (p=0,003). Diferença significativa (p-=0,023) foi observada para inflamação aguda no grupos controle experimento de sete dias. Na análise intra-grupo (controle três e sete), foi observado efeito marginalmente significativo (p=0,094 e p=0,05) respectivamente para as variáveis inflamação aguda e crônica. Na análise somente entre os grupos experimentos, as variáveis reação gigantocelular (0,002) e colagenização (0,016) apresentaram resultado significativo. A avaliação tensiométrica mostrou diferença significativa em relação ao grupo experimento de sete...

INTRODUCTION: The babassu mesocarp (Orbignya phalerata) has been used in experimental research studies focused on its antiinflammatory action. In state of Maranhão - Brazil it is widely used not only as food, but also as popular medicine in wound healing process. PURPOSE: To evaluate the action of Orbignya phalerata extract in macroscopic, histologicic and tensiometric aspects in the healing process of median laparotomy in rats. METHODS: Forty male adult Wistar rats were submitted to an incision in the alba linea, sutured back in one plan with separated stitches of polypropilene 5-0. After regular procedure, the animals were divided into two groups of 20 rats each. To the group named control an intraperitoneal, dose of 1,0 ml of saline solution per kilogram of body weight was done. To the experimental group, the same thing was also done, but instead of saline solution it was injected water solution of babassu, in a dose of 50 mg/kg. The animals were observed in the following days. All of them were killed within a three and seven day post-operative period schedule, and then a histological and tensiometric analysis was carried out. RESULTS: On macroscopic examination no relevant adherence, between the alba linea and the abdominal organs in the study groups, was found. Histological evaluation presented marginal significant effects (p=0,86) to acute inflammation and significant effects (p=0,003) to giant cell reaction in both control and experimental three days groups. Significant difference was observed to acute inflammation in both seven days control and experimental groups. In the intragroup analysis (control three and seven) some marginal significant effect was in relationship to acute and chronic inflammation. In the interexperimental groups analysis, only the giant cell reactions (0,002) and colagenization had significant results. The tensiometric evaluation showed in the seven day experimental group more resistence then others...

Efeito do tenoxican sobre o intervalo QTc e sua dispersäo no período pós-operatório imediato / Effect of tenoxicam on the QTc interval and its dispersion in the immediate postoperative period

Justificativa e objetivos: a dispersäo do intervalo QTc é um índice de dispersäo da refratariedade no sincício miocárdico e associa-se à incidência de disritmias ventriculares em diversas situaçöes clínicas. Os antinflamatórios näo esteróides diminuem a dispersäo da refratariedade e as disritimias induzidas por isquemia miocárdica, provavelmente por inibirem a síntese de tromboxane A2. Este estudo teve por objetivo avaliar o efeito do tenoxican sobre a dispersäo do intervalo QTc no período pós-operatório imediato. Método: foram analisados os eletrocardiogramas registrados antes (M1) e 20 minutos após (M2) a administraçäo de soluçäo fisiológica (grupo 1) ou 20 mg de tenoxicam (grupo 2), por via venosa, em 54 pacientes adultos submetidos a cirurgias eletivas sob anestesia geral ou regional, na primeira hora do período pós-anestésico imediato. A pressäo arterial, a frequência cardíaca e a frequência respiratória foram medidas nos mesmos momentos. Resultados: os intervalos QTc médios foram: no grupo 1, 413ñ49 e 410ñ36 ms em M1 e M2, respectivamente, e no grupo 2, foram 419ñ40 e 410ñ34 ms, sem diferenças significativas intra ou inter-grupos. Dispersäo do intervalo QTc acima de 60 ms(elevado a 1/2) ocorreu em 56 por cento e 72,41 por cento dos pacientes dos grupos 1 e 2, respectivamente, em M1 e 64 por cento e 58,62 em M2, sem diferenças entre os grupos. A dispersäo média foi maior que 60 ms(elevado a 1/2) em ambos os grupos, sem alteraçäo siginificativa de M1 para M2, näo diferindo entre os grupos. Näo se observaram alteraçöes significativas na pressäo arterial, frequência cardíaca ou frequência respiratória. Conclusöes: embora dispersäo aumentada do intervalo QTc tenha sido encontrada em uma percentagem elevada de pacientes, a administraçäo de tenoxicam näo afetou a duraçäo do intervalo QTc e nem sua dispersäo