Association between symptoms of COVID-19 infection and adverse maternal-perinatal outcomes in pregnant women at a referral hospital. / Asociación entre los síntomas de la infección por la COVID-19 y los resultados materno-perinatales adversos en gestantes de un hospital de referencia.

OBJECTIVES.: To determine the association between symptoms of COVID-19 infection and adverse maternal-perinatal outcomes in pregnant women from a referral hospital. MATERIALS AND METHODS.: Analytical cross-sectional study of women in the third trimester of pregnancy hospitalized due to COVID-19 in the gynecology and obstetrics area of a general hospital in Lima during 2020. Clinical and obstetric variables were collected. Fisher's exact test and Chi-square test were used during the descriptive analysis. Poisson regression was used to find the association between the variables of interest, with a 95% confidence interval (95%CI). RESULTS.: A total of 272 pregnant women were included, 50.3% of whom had symptoms of infection. Of these, 35.7% of the pregnant women and 16.5% of the newborns had an adverse outcome. Having symptoms of COVID-19 infection increased the risk of maternal complications as a whole (PR= 2.32 95%CI: 1.61-3.34), premature rupture of membranes (PR= 2.73 95%CI: 1.51-4.94) and preeclampsia (PR= 2.73 95%CI: 1.51-4.94). Similarly, symptoms of COVID-19 infection increased the risk of perinatal complications as a whole (PR= 2.51 95%CI: 1.34-4.68) and acute fetal distress (PR= 2.99 95%CI: 1.07-8.38). CONCLUSIONS.: The presence of symptoms of COVID-19 infection increase the risk of adverse maternal-perinatal outcomes.

OBJETIVOS.: Determinar la asociación entre los síntomas de la infección por la COVID-19 y los resultados materno-perinatales adversos en gestantes de un hospital de referencia. MATERIALES Y MÉTODOS.: Estudio transversal analítico en gestantes en el tercer trimestre, hospitalizadas por la COVID-19 en el área de ginecología y obstetricia de un hospital general de Lima, en el 2020. Se recogieron variables clínicas y obstétricas. Para el análisis descriptivo se empleó la prueba exacta de Fisher y Chi Cuadrado, y para hallar la asociación entre las variables de interés se usó la regresión de Poisson, con un intervalo de confianza al 95% (IC95%). RESULTADOS.: Se incluyeron a 272 gestantes, de ellas el 50,3% tuvieron síntomas de infección. El 35,7% de las gestantes y el 16,5% de los recién nacidos tuvieron un resultado adverso. Tener síntomas de la infección por la COVID-19 aumentó el riesgo de complicaciones maternas en su conjunto (RP= 2,32 IC95%: 1,61-3,34), de ruptura prematura de membranas (RP= 2,73 IC95%: 1,51-4,94) y de preeclampsia (RP= 2,73 IC95%: 1,51-4,94). De igual forma, aumentó el riesgo de complicaciones perinatales en su conjunto (RP= 2,51 IC95%: 1,34-4,68) y de sufrimiento fetal agudo (RP= 2,99 IC95%: 1,07-8,38). CONCLUSIONES.: Los síntomas de la infección por la COVID-19 aumentan el riesgo de resultados materno-perinatales adversos.

Processing, Characterization and Disintegration Properties of Biopolymers Based on Mater-Bi® and Ellagic Acid/Chitosan Coating.

Among the most promising synthetic biopolymers to replace conventional plastics in numerous applications is MaterBi® (MB), a commercial biodegradable polymer based on modified starch and synthetic polymers. Actually, MB has important commercial applications as it shows interesting mechanical properties, thermal stability, processability and biodegradability. On the other hand, research has also focused on the incorporation of natural, efficient and low-cost active compounds into various materials with the aim of incorporating antimicrobial and/or antioxidant capacities into matrix polymers to extend the shelf life of foods. Among these is ellagic acid (EA), a polyphenolic compound abundant in some fruits, nuts and seeds, but also in agroforestry and industrial residues, which seems to be a promising biomolecule with interesting biological activities, including antioxidant activity, antibacterial activity and UV-barrier properties. The objective of this research is to develop a film based on commercial biopolymer Mater-Bi® (MB) EF51L, incorporating active coating from chitosan with a natural active compound (EA) at two concentrations (2.5 and 5 wt.%). The formulations obtained complete characterization and were carried out in order to evaluate whether the incorporation of the coating significantly affects thermal, mechanical, structural, water-vapor barrier and disintegration properties. From the results, FTIR analysis yielded identification, through characteristic peaks, that the type of MB used is constituted by three polymers, namely PLA, TPS and PBAT. With respect to the mechanical properties, the values of tensile modulus and tensile strength of the MB-CHI film were between 15 and 23% lower than the values obtained for the MB film. The addition of 2.5 wt.% EA to the CHI layer did not generate changes in the mechanical properties of the system, whereas a 5 wt.% increase in ellagic acid improved the mechanical properties of the CHI film through the addition of natural phenolic compounds at high concentrations. Finally, the disintegration process was mainly affected by the PBAT biopolymer, causing the material to not disintegrate within the times indicated by ISO 20200.

Asociación entre los síntomas de la infección por la COVID-19 y los resultados materno-perinatales adversos en gestantes de un hospital de referencia / Association between symptoms of COVID-19 infection and adverse maternal-perinatal outcomes in pregnant women at a referral hospital

Objetivos. Determinar la asociación entre los síntomas de la infección por la COVID-19 y los resultados materno-perinatales adversos en gestantes de un hospital de referencia. Materiales y métodos. Estudio transversal analítico en gestantes en el tercer trimestre, hospitalizadas por la COVID-19 en el área de ginecología y obstetricia de un hospital general de Lima, en el 2020. Se recogieron variables clínicas y obstétricas. Para el análisis descriptivo se empleó la prueba exacta de Fisher y Chi Cuadrado, y para hallar la asociación entre las variables de interés se usó la regresión de Poisson, con un intervalo de confianza al 95% (IC95%). Resultados. Se incluyeron a 272 gestantes, de ellas el 50,3% tuvieron síntomas de infección. El 35,7% de las gestantes y el 16,5% de los recién nacidos tuvieron un resultado adverso. Tener síntomas de la infección por la COVID-19 aumentó el riesgo de complicaciones maternas en su conjunto (RP= 2,32 IC95%: 1,61-3,34), de ruptura prematura de membranas (RP= 2,73 IC95%: 1,51-4,94) y de preeclampsia (RP= 2,73 IC95%: 1,51-4,94). De igual forma, aumentó el riesgo de complicaciones perinatales en su conjunto (RP= 2,51 IC95%: 1,34-4,68) y de sufrimiento fetal agudo (RP= 2,99 IC95%: 1,07-8,38). Conclusiones. Los síntomas de la infección por la COVID-19 aumentan el riesgo de resultados materno-perinatales adversos.

Objectives. To determine the association between symptoms of COVID-19 infection and adverse maternal-perinatal outcomes in pregnant women from a referral hospital. Materials and methods. Analytical cross-sectional study of women in the third trimester of pregnancy hospitalized due to COVID-19 in the gynecology and obstetrics area of a general hospital in Lima during 2020. Clinical and obstetric variables were collected. Fisher's exact test and Chi-square test were used during the descriptive analysis. Poisson regression was used to find the association between the variables of interest, with a 95% confidence interval (95%CI). Results. A total of 272 pregnant women were included, 50.3% of whom had symptoms of infection. Of these, 35.7% of the pregnant women and 16.5% of the newborns had an adverse outcome. Having symptoms of COVID-19 infection increased the risk of maternal complications as a whole (PR= 2.32 95%CI: 1.61-3.34), premature rupture of membranes (PR= 2.73 95%CI: 1.51-4.94) and preeclampsia (PR= 2.73 95%CI: 1.51-4.94). Similarly, symptoms of COVID-19 infection increased the risk of perinatal complications as a whole (PR= 2.51 95%CI: 1.34-4.68) and acute fetal distress (PR= 2.99 95%CI: 1.07-8.38). Conclusions. The presence of symptoms of COVID-19 infection increase the risk of adverse maternal-perinatal outcomes.

Clinical Characteristics of Coronavirus Disease (COVID-19) in Mexican Children and Adolescents.

BACKGROUND: We analyzed the demographic, clinical, and diagnostic data of children and adolescents in Mexico, from the first case of coronavirus disease (COVID-19) to 28 February 2022. METHODS: Using the open databases of the Ministry of Health and a tertiary pediatric hospital, we obtained demographic and clinical data from the beginning of the COVID-19 pandemic until 28 February 2022. In addition, quantitative reverse-transcription polymerase chain reaction outputs were used to determine the viral load, and structural protein-based serology was performed to evaluate IgG antibody levels. RESULTS: Of the total 437,832 children and adolescents with COVID-19, 1187 died. Of these patients, 1349 were admitted to the Hospital Infantil de Mexico Federico Gómez, and 11 died. Obesity, asthma, and immunosuppression were the main comorbidities, and fever, cough, and headache were the main symptoms. In this population, many patients have a low viral load and IgG antibody levels. CONCLUSION: During the first 2 years of the COVID-19 pandemic in Mexico, children and adolescents had low incidence and mortality. They are a heterogeneous population, but many patients had comorbidities such as obesity, asthma, and immunosuppression; symptoms such as fever, cough, and headache; and low viral load and IgG antibodies.

Processing Compostable PLA/Organoclay Bionanocomposite Foams by Supercritical CO2 Foaming for Sustainable Food Packaging.

This article proposes a foaming method using supercritical carbon dioxide (scCO2) to obtain compostable bionanocomposite foams based on PLA and organoclay (C30B) where this bionanocomposite was fabricated by a previous hot melt extrusion step. Neat PLA films and PLA/C30B films (1, 2, and 3 wt.%) were obtained by using a melt extrusion process followed by a film forming process obtaining films with thicknesses between 500 and 600 µm. Films were further processed into foams in a high-pressure cell with scCO2 under constant conditions of pressure (25 MPa) and temperature (130 °C) for 30 min. Bionanocomposite PLA foams evidenced a closed cell and uniform cell structure; however, neat PLA presented a poor cell structure and thick cell walls. The thermal stability was significantly enhanced in the bionanocomposite foam samples by the good dispersion of nanoclays due to scCO2, as demonstrated by X-ray diffraction analysis. The bionanocomposite foams showed improved overall mechanical performance due to well-dispersed nanoclays promoting increased interfacial adhesion with the polymeric matrix. The water uptake behavior of bionanocomposite foams showed that they practically did not absorb water during the first week of immersion in water. Finally, PLA foams were disintegrated under standard composting conditions at higher rates than PLA films, showing their sustainable character. Thus, PLA bionanocomposite foams obtained by batch supercritical foaming seem to be a sustainable option to replace non-biodegradable expanded polystyrene, and they represent a promising alternative to be considered in applications such as food packaging and other products.

Active PLA Packaging Films: Effect of Processing and the Addition of Natural Antimicrobials and Antioxidants on Physical Properties, Release Kinetics, and Compostability.

The performance characteristics of polylactic acid (PLA) as an active food packaging film can be highly influenced by the incorporation of active agents (AAs) into PLA, and the type of processing technique. In this review, the effect of processing techniques and the addition of natural AAs on the properties related to PLA performance as a packaging material are summarized and described through a systematic analysis, giving new insights about the relation between processing techniques, types of AA, physical-mechanical properties, barriers, optical properties, compostability, controlled release, and functionalities in order to contribute to the progress made in designing antioxidant and antimicrobial PLA packaging films. The addition of AAs into PLA films affected their optical properties and influenced polymer chain reordering, modifying their thermal properties, functionality, and compostability in terms of the chemical nature of AAs. The mechanical and barrier performance of PLA was affected by the AA's dispersion degree and crystallinity changes resulting from specific processing techniques. In addition, hydrophobicity and AA concentration also modified the barrier properties of PLA. The release kinetics of AAs from PLA were tuned, modifying diffusion coefficient of the AAs in terms of the different physical properties of the films that resulted from specific processing techniques. Several developments based on the incorporation of antimicrobial and antioxidant substances into PLA have displayed outstanding activities for food protection against microbial growth and oxidation.

Obtaining Active Polylactide (PLA) and Polyhydroxybutyrate (PHB) Blends Based Bionanocomposites Modified with Graphene Oxide and Supercritical Carbon Dioxide (scCO2)-Assisted Cinnamaldehyde: Effect on Thermal-Mechanical, Disintegration and Mass Transport Properties.

Bionanocomposites based on Polylactide (PLA) and Polyhydroxybutyrate (PHB) blends were successfully obtained through a combined extrusion and impregnation process using supercritical CO2 (scCO2). Graphene oxide (GO) and cinnamaldehyde (Ci) were incorporated into the blends as nano-reinforcement and an active compound, respectively, separately, and simultaneously. From the results, cinnamaldehyde quantification values varied between 5.7% and 6.1% (w/w). When GO and Ci were incorporated, elongation percentage increased up to 16%, and, therefore, the mechanical properties were improved, with respect to neat PLA. The results indicated that the Ci diffusion through the blends and bionanocomposites was influenced by the nano-reinforcing incorporation. The disintegration capacity of the developed materials decreased with the incorporation of GO and PHB, up to 14 and 23 days of testing, respectively, without compromising the biodegradability characteristics of the final material.

Natural antimicrobials and antioxidants added to polylactic acid packaging films. Part I: Polymer processing techniques.

Currently, reducing packaging plastic waste and food losses are concerning topics in the food packaging industry. As an alternative for these challenges, antimicrobial and antioxidant materials have been developed by incorporating active agents (AAs) into biodegradable polymers to extend the food shelf life. In this context, developing biodegradable active materials based on polylactic acid (PLA) and natural compounds are a great alternative to maintain food safety and non-toxicity of the packaging. AAs, such as essential oils and polyphenols, have been added mainly as antimicrobial and antioxidant natural compounds in PLA packaging. In this review, current techniques used to develop active PLA packaging films were described in order to critically compare their feasibility, advantages, limitations, and relevant processing aspects. The analysis was focused on the processing conditions, such as operation variables and stages, and factors related to the AAs, such as their concentrations, weight losses during processing, and incorporation technique, among others. Recent developments of active PLA-based monolayers and bi- or multilayer films were also considered. In addition, patents on inventions and technologies on active PLA-based films for food packaging were reviewed. This review highlights that the selection of the processing technique and conditions to obtain active PLA depends on the type of the AA regarding its volatility, solubility, and thermosensitivity.

Designing Biodegradable and Active Multilayer System by Assembling an Electrospun Polycaprolactone Mat Containing Quercetin and Nanocellulose between Polylactic Acid Films.

The design of multilayer systems is an innovative strategy to improve physical properties of biodegradable polymers and introduce functionality to the materials through the incorporation of an active compound into some of these layers. In this work, a trilayer film based on a sandwich of electrospun polycaprolactone (PCL) fibers (PCLé) containing quercetin (Q) and cellulose nanocrystals (CNC) between extruded polylactic acid (PLA) films was designed with the purpose of improving thermal and barrier properties and affording antioxidant activity to packaged foods. PCLé was successfully electrospun onto 70 µm-thick extruded PLA film followed by the assembling of a third 25 µm-thick commercial PLA film through hot pressing. Optical, morphological, thermal, and barrier properties were evaluated in order to study the effect of PCL layer and the addition of Q and CNC. Bilayer systems obtained after the electrospinning process of PCL onto PLA film were also evaluated. The release of quercetin from bi- and trilayer films to food simulants was also analyzed. Results evidenced that thermal treatment during thermo-compression melted PCL polymer and resulted in trilayer systems with barrier properties similar to single PLA film. Quercetin release from bi- and trilayer films followed a similar profile, but achieved highest value through the addition of CNC.

Dolor neuropático en pacientes diabéticos insulinodependientes / Neuropathic pain in insulin-dependent diabetic patients

Resumen: Introducción: El dolor neuropático es complejo y, a pesar de los avances farmacológicos y no farmacológicos de los últimos años, es la principal causa de sufrimiento en pacientes diabéticos insulinodependientes. Objetivo: Realizar una revisión no sistemática de la literatura sobre el dolor neuropático en el paciente diabético insulinodependiente. Material y métodos: Se realizó una búsqueda bibliográfica de la literatura, el día 03 de agosto de 2019, en las bases de datos PubMed, de la Biblioteca Médica Nacional de los Estados Unidos (NLM), con los siguientes descriptores en idioma inglés: diabetes mellitus insulinodependiente AND neuropatic pain, lo cual ofreció un total de 133 publicaciones. Cuando se activó el filtro en humanos se mantuvieron 11 artículos. Con el filtro en los últimos cinco años, a texto completo, permaneció uno cuyo título no está relacionado con el proyecto propuesto. Conclusiones: El paciente diabético insulinodependiente, en sentido general, presenta dolor neuropático de intensidad variable, que afecta su calidad de vida y que requiere tratamiento especializado.

Abstract: Introduction: Neuropathic pain is complex and despite the pharmacological and non-pharmacological advances of recent years, it is the main cause of suffering in insulin-dependent diabetic patients. Objective: To update a non-systematic review of the literature on neuropathic pain in the insulin-dependent diabetic patient. Material and methods: A literature search was conducted on August 3 of 2019 in the PubMed databases of the National Medical Library of the United States (NLM), with the following English-language descriptors: insulin-dependent diabetes mellitus AND neuropathic pain, which offered a total of 133 publications. When the filter was activated in humans, 11 articles were maintained. With the filter in the last five years, full text remained one whose title is not related to the proposed project. Conclusions: The general insulin-dependent diabetic patient presents with neuropathic pain of varying intensity, which affects their quality of life and requires specialized treatment.

Effect of supercritical incorporation of cinnamaldehyde on physical-chemical properties, disintegration and toxicity studies of PLA/lignin nanocomposites.

Poly (lactic acid)/lignin nanocomposites (PLA/Lig-Np) containing cinnamaldehyde (Ci) were obtained by a combination of melt extrusion and supercritical impregnation process. In this work, Ci impregnation tests were carried out in a high-pressure cell at 40 °C for 3 h using 12 MPa and 1 MPa min-1 of depressurization rate, obtaining impregnation yields ranging from 5.7 to 10.8% w/w. Thermal, mechanical and colorimetric properties of the developed films were affected by the incorporation of lignin nanoparticles and the active compound, obtaining biodegradable plastic materials with a strong UV-light barrier property compared to PLA films. In addition, disintegrability tests under composting conditions confirmed the biodegradable character of nanocomposites developed. On day 23, a disintegration percentage greater than 90% was determined for all bionanocomposites. Finally, to establish the possible toxicity effect of the nanocomposites obtained, studies in vivo were performed in normal rats. Toxicity studies showed normal blood parameters after a single dose of nanocomposites. PLA/Ci/Lig-Np bionanocomposite films could be potentially applied to design biodegradable UV-light barrier materials for food packaging and biomedical applications.

The use of nanoadditives within recycled polymers for food packaging: Properties, recyclability, and safety.

Nanotechnology is considered a highly valued technology to reduce the current environmental problem that is derived from plastic accumulation. The need to recycle and reuse packaging materials is essential to create a sustainable society towards a circular economy. However, the reprocessing of polymers leads to the deterioration of their characteristic mechanical, optical, thermal, and barrier properties due to the degradation of their polymeric chains. When recycled polymers are reinforced with nanoadditives, aforementioned properties improve and their use in the circular economy is more viable. In this review, different types of nanoadditives and recent advances in the development of recycled polymer nanocomposites reinforced with nanoadditives will be presented. In addition, there is a description of two research topics of current interest, recyclability of nanocomposites and safety for food packaging applications. Recyclability of nanocomposites requires a study that includes the nature of the polymer matrix, the type of polymer and the concentration of nanofiller, the morphology, the presence of additives, and the conditions of the thermal-mechanical cycles. Finally, safety section is dedicated to clarify the migration process in nanoreinforced-recycled polymers in order to assess their safety for food contact applications.

Ozonoterapia sistémica en pacientes diabéticos insulinodependientes con dolor neuropático / Systemic ozone therapy in insulin-dependent diabetic patients with neuropathic pain

Introducción: Con frecuencia, los pacientes diabéticos presentan dolor neuropático como complicación de su enfermedad. Objetivo: Identificar las ventajas de la ozonoterapia sistémica en pacientes diabéticos insulinodependientes con dolor neuropático. Métodos: Se realizó un estudio descriptivo en diabéticos insulinodependientes con dolor neuropático que acudieron a la Clínica del Dolor del Hospital Clínico Quirúrgico Hermanos Ameijeiras entre febrero de 2014 hasta enero de 2019. A todos se les cuantificó el dolor, la presencia de parestesias, la fuerza muscular, el reflejo aquiliano y la hemoglobina glicosilada. Se administraron 15 sesiones de ozono vía rectal y 6 de autohemoterapia mayor. Se compararon los resultados de la primera sesión y en la última (8 semanas de tratamiento). Resultados: El 45,3 por ciento tenían 60 años o más, 59 por ciento eran del sexo femenino y 89,3 por ciento tenían 15 o más años de evolución de la diabetes. En la primera consulta la intensidad del dolor en 100 por ciento osciló entre 7 y 10 de la escala numérica verbal y todos presentaron parestesias. En 59,3 por ciento existió disminución de la fuerza muscular, 62 por ciento presentó reflejo aquiliano disminuido y 88 por ciento hemoglobina glicosilada mayor o igual a 12 por ciento. Estos síntomas mejoraron a las ocho semanas. Conclusiones: Las probadas propiedades analgésicas y antiinflamatorias del ozono lo convierten en la actualidad en una herramienta terapéuticas de las más eficientes para el control del dolor crónico en pacientes diabéticos insulinodependientes(AU)

Introduction: Frequently, diabetic patients present neuropathic pain as a complication of their disease. Objective: To identify the advantages of systemic ozone therapy for insulin-dependent diabetic patients with neuropathic pain. Methods: A descriptive study was carried out with insulin-dependent diabetic patients with neuropathic pain who attended the Pain Clinic of Hermanos Ameijeiras Clinical-Surgical Hospital between February 2014 until January 2019. All of them were quantified pain, the presence of paresthesias, muscle strength, ankle jerk reflex, and glycosylated hemoglobin. The patients received fifteen sessions of rectal ozone and six sessions of major self-hemotherapy. We compared the outcomes after the first session and after the last one (eight weeks). Results: 45.3 percent were 60 years or older, 59 percent were female, and 89.3 percent had a natural history of diabetes of 15 years or more. In the first hospital visit, the intensity of 100 percent pain ranged between 7 and 10 according to the verbal numeric scale, and all presented paresthesias. In 59.3 percent, there was a decrease in muscle strength, 62 percent had decreased ankle jerk reflex, and 88 percent had glycosylated hemoglobin higher than or equal to 12 percent. These symptoms improved at week eight. Conclusions: The proven analgesic and anti-inflammatory properties of ozone make it currently a therapeutic tool among the most efficient for controlling chronic pain in insulin-dependent diabetic patients(AU)

Supercritical impregnation for food applications: a review of the effect of the operational variables on the active compound loading.

The scCO2-assisted impregnation process has arisen as an effective method to impregnate solid materials. Its multiple advantages include high diffusion, it allows to obtain free-solvent materials and to operate under low temperatures, which permits to process thermolabile solutes. These characteristics have allowed its application at industrial scale for the impregnation of wood with fungicides and in the last years for textile dyeing. Meanwhile, other numerous applications are still being studied at laboratory scale. One potential field of application corresponds to the food-related industry, which includes the use of scCO2-assisted impregnation process to develop active materials for food packaging and to generate food-grade materials loaded with nutraceuticals for functional food applications. In this framework, this article summarizes the advantages and the main drawbacks with the scCO2-assisted impregnation process. The effect of the processing variables of the scCO2-assisted impregnation process is discussed in terms of the incorporation of active compounds within polymer structures. Including the principles and description of the process and a review of the investigated systems for a better understanding.

Development of Bilayer Biodegradable Composites Containing Cellulose Nanocrystals with Antioxidant Properties.

The interest in the development of novel biodegradable composites has increased over last years, and multilayer composites allow the design of materials with functionality and improved properties. In this work, bilayer structures based on a coated zein layer containing quercetin and cellulose nanocrystals (CNC) over an extruded poly(lactic acid) (PLA) layer were developed and characterized. Bilayer composites were successfully obtained and presented a total thickness of approx. 90 µm. The coated zein layer and quercetin gave a yellowish tone to the composites. The incorporation of the zein layer containing CNC decreased the volatile release rate during thermal degradation. Regarding to mechanical properties, bilayer composites presented lower brittleness and greater ductility evidenced by a lower Young's modulus and higher elongation values. Water permeability values of bilayer composites greatly increased with humidity and the zein coated layer containing quercetin increased this effect. Experimental data of quercetin release kinetics from bilayer structures indicated a higher release for an alcoholic food system, and the incorporation of cellulose nanocrystals did not influence the quercetin diffusion process.

Modifying an Active Compound's Release Kinetic Using a Supercritical Impregnation Process to Incorporate an Active Agent into PLA Electrospun Mats.

The main objective of this work was to study the release of cinnamaldehyde (CIN) from electrospun poly lactic acid (e-PLA) mats obtained through two techniques: (i) direct incorporation of active compound during the electrospinning process (e-PLA-CIN); and (ii) supercritical carbon dioxide (scCO2) impregnation of CIN within electrospun PLA mats (e-PLA/CINimp). The development and characterization of both of these active electrospun mats were investigated with the main purpose of modifying the release kinetic of this active compound. Morphological, structural, and thermal properties of these materials were also studied, and control mats e-PLA and e- PLA CO 2 were developed in order to understand the effect of electrospinning and scCO2 impregnation, respectively, on PLA properties. Both strategies of incorporation of this active compound into PLA matrix resulted in different morphologies that influenced chemical and physical properties of these composites and in different release kinetics of CIN. The electrospinning and scCO2 impregnation processes and the presence of CIN altered PLA thermal and structural properties when compared to an extruded PLA material. The incorporation of CIN through scCO2 impregnation resulted in higher release rate and lower diffusion coefficients when compared to active electrospun mats with CIN incorporated during the electrospinning process.

Supercritical impregnation of cinnamaldehyde into polylactic acid as a route to develop antibacterial food packaging materials.

Supercritical impregnation was used to incorporate a natural compound with antibacterial activity into biopolymer-based films to develop active food packaging materials. Impregnation tests were carried out under two pressure conditions (9 and 12MPa), and three depressurization rates (0.1, 1 and 10MPamin-1) in a high-pressure cell at a constant temperature equal to 40°C. Cinnamaldehyde (Ci), a natural compound with proven antimicrobial activity, was successfully incorporated into poly(lactic acid) films (PLA) using supercritical carbon dioxide (scCO2), with impregnation yields ranging from 8 to 13% w/w. Higher pressure and slower depressurization rate seem to favor the Ci impregnation. The incorporation of Ci improved thermal, structural and mechanical properties of the PLA films. Impregnated films were more flexible, less brittle and more resistant materials than neat PLA films. The tested samples showed strong antibacterial activity against the selected microorganisms. In summary, this study provides an innovative route to the development of antibacterial biodegradable materials, which could be used in a wide range of applications of active food packaging.

Pragmatics of the Development of Personal Identity in Adolescents in the Latin American Context.

The present work proposes a pragmatic perspective of the development of personal identity. Such perspective is based on a unifying vision that incorporates the contribution of communicative pragmatics and becomes aware of the contribution of semiotics to psychology, without leaving aside the eriksonian point of view and other significant contributions in the field. The article defines identity in adolescence from a development approach, and adopts a systemic perspective concerning the insertion of adolescents in their context of formation as individuals. It then proposes a way to understand identity from a pragmatic-communicative perspective. Finally, it introduces two communicative use contexts from which personal identity can emerge, showing the importance of communication and language in the formation and development of identity.

Capreomycin oleate microparticles for intramuscular administration: Preparation, in vitro release and preliminary in vivo evaluation.

Capreomycin sulfate (CS) is a second-line drug used for the treatment of multidrug-resistant tuberculosis (MDR-TB). The adverse effects profile and uncomfortable administration scheme of CS has led to the development of formulations based on liposomes and polymeric microparticles. However, as CS is a water-soluble peptide that does not encapsulate properly into hydrophobic particulate matrices, it was necessary to reduce its aqueous solubility by forming the pharmacologically active capreomycin oleate (CO) ion pair. The aim of this research was to develop a new formulation of CO for intramuscular injection, based on biodegradable microparticles that encapsulate CO in order to provide a controlled release of the drug with reduced local and systemic adverse effects. The CO-loaded microparticles prepared by spray drying or solvent emulsion-evaporation were characterized in their morphology, encapsulation efficiency, in vitro/in vivo kinetics and tissue tolerance. Through scanning electron microscopy it was confirmed that the microparticles were monodisperse and spherical, with an optimal size for intramuscular administration. The interaction between CO and the components of the microparticle matrix was confirmed on both formulations by X-ray powder diffraction and differential scanning calorimetry analyses. The encapsulation efficiencies for the spray-dried and emulsion-evaporation microparticles were 92% and 56%, respectively. The in vitro kinetics performed on both formulations demonstrated a controlled and continuous release of CO from the microparticles, which was successfully reproduced on an in vivo rodent model. The results of the histological analysis demonstrated that none of the formulations produced significant tissue damage on the site of injection. Therefore, the results suggest that injectable CO microparticles obtained by spray drying and solvent emulsion-evaporation could represent an interesting therapeutic alternative for the treatment of MDR-TB.

[EXTENDED LYMPHA DENECTOMY SURVIVAL EFFICACY IN PATIENTS WITH ADVANCED GASTRIC CARCINOMA] / Eficacia de la linfadenectomía extendida en la sobrevida de pacientes con carcinoma gástrico avanzado.

OBJECTIVES: Determine the 5-year survival rate, prognostic factors, postoperative morbidity and mortality rates and the accuracy of the Maruyama computer program.MATERIAL and METHODS: This prospective study evaluated 32 patients with advanced gastric adenocarcinoma underwent radical gastrectomy with D2 (n= 13) or D3-D4 (n= 19) extended lymphadenectomy, at Belen Hospital, Trujillo, Peru, from 1990 to 1998.RESULTS: Gastric cancer patients (20 F: 12 M) had a median age of 55.4 + 14.5 years (range, 20 to 76 years). In D3-D4 patients there was a significant increased in the number of cases with lesions type Borrmann III-IV (p= 0.03), N3 (p= 0.04), M1 (p= 0.04) and undifferentiated type in histology (p= 0.04) compared with D2 cases. The 5-year survival in curative and palliative surgery was of 48.9% and 10.7%, respectively (p<0.001). The 5-year survival in D2 surgery was of 42.7% and in D3-D4 was of 27.6% (p= NS). The 5-year survival rate in the total series was of 30.9%. Location (p< 0.05) and size of the tumor (p< 0.01), distant metastases (p< 0.05), clinical stage (p< 0.05), Borrmann's type (p< 0.05) and curability (p< 0.05) were factors that influenced long-term survival. The morbidity rate with D2 and D3-D4 disection was of 30.7% and 57.8%, respectively (p= NS), and in the total series was of 46.8%. The mortality rate in this series was of 3.1%. The prediction of the lymphs node metastases with the computer program was highly exact (13-16: 100%, 7-12: 75%, 1-6: 66%).CONCLUSIONS: Extended lymphadenectomy had a low surgical mortality but high morbidity and permitted that one third of advanced gastric cancer patients underwent surgery obtains 5-year survival.