Poly-Lactic Acid-Bagasse Based Bio-Composite for Additive Manufacturing.

Beer bagasse is a residue waste produced in great amounts; nevertheless, it is still underestimated in the industry. The aim of this paper is to develop an innovative and efficient methodology to recycle the beer bagasse by producing Poly-lactic acid(PLA)-based bio-composites, in the forms of pellets and filaments, to be used in additive manufacturing processes. To assess the suitability of beer bagasse for extrusion-based 3D printing techniques, it was, firstly, physically and chemically characterized. Then, it was added in combination with different kinds of plasticizers to PLA to make bio-composites, analyzing their thermal and physical properties. The results prove the great potential of bagasse, evidencing its printability. Both composites' pellets and filaments were used in two different 3D printing machines and the mechanical properties of the 3D-printed models were evaluated as a function of the composition and the kind of technology used. All the used plasticizers improved processability and the polymer-bagasse interface. Compared to neat PLA, no changes in thermal properties were detected, but a lowering of the mechanical properties of the 3D-printed composites compared to the neat polymers was observed. Finally, a comparison between the efficiency of the two 3D printing techniques to be used with the bio-based composites was performed.

Incorporation of Argan Shell Flour in a Biobased Polypropylene Matrix for the Development of High Environmentally Friendly Composites by Injection Molding.

In this study, a new composite material is developed using a semi bio-based polypropylene (bioPP) and micronized argan shell (MAS) byproducts. To improve the interaction between the filler and the polymer matrix, a compatibilizer, PP-g-MA, is used. The samples are prepared using a co-rotating twin extruder followed by an injection molding process. The addition of the MAS filler improves the mechanical properties of the bioPP, as evidenced by an increase in tensile strength from 18.2 MPa to 20.8 MPa. The reinforcement is also observed in the thermomechanical properties, with an increased storage modulus. The thermal characterization and X-ray diffraction indicate that the addition of the filler leads to the formation of α structure crystals in the polymer matrix. However, the addition of a lignocellulosic filler also leads to an increased affinity for water. As a result, the water uptake of the composites increases, although it remains relatively low even after 14 weeks. The water contact angle is also reduced. The color of the composites changes to a color similar to wood. Overall, this study demonstrates the potential of using MAS byproducts to improve their mechanical properties. However, the increased affinity with water should be taken into account in potential applications.

Development of Blends to Improve Flexibility of Biodegradable Polymers.

In this study, binary blends of biodegradable polymers were prepared to improve the ductile properties of those that have a more rigid and/or brittle behaviour. Specifically, PLA, PHA and TPS were blended with different amounts of PBS with the objective of reducing the stiffness and brittleness of the three polymers. The compatibility of the blends and their resulting mechanical properties were studied. The flexibility of the blends increased with the addition of PBS; however, a limited compatibility was achieved, leading to a low impact resistance improvement. For this reason, other blend options with an EVA-based material were studied, increasing the impact resistance and flexibility of the PLA material in this case.

Recyclability Analysis of Starch Thermoplastic/Almond Shell Biocomposite.

This article is focused on studying the effect of the reprocessing cycles on the mechanical, thermal, and aesthetic properties of a biocomposite. This process is based on starch thermoplastic polymer (TPS) filled with 20 wt% almond shell powder (ASP) and epoxidized linseed oil (ELO) as a compatibilizing additive. To do so, the biocomposite was prepared in a twin-screw extruder, molded by injection, and characterized in terms of its mechanical, thermal, and visual properties (according to CieLab) and the melt flow index (MFI). The analyses carried out were tensile, flexural, Charpy impact tests, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA). The effects of the reprocessing were also studied for the biodegradable unfilled TPS polymer. The results showed that TPS and TPS/ASP biocomposite suffer changes progressively on the properties studied after each reprocessing cycle. Furthermore, it was observed that the addition of ASP intensified these effects regarding TPS. However, in spite of the progressive degradation in both cases, it is technically feasible to reprocess the material at least three times without needing to incorporate virgin material.

Study of the Influence of the Almond Shell Variety on the Mechanical Properties of Starch-Based Polymer Biocomposites.

This article is focused on the development of a series of biodegradable and eco-friendly biocomposites based on starch polymer (Mater-Bi DI01A) filled with 30 wt% almond shell (AS) of different varieties (Desmayo Rojo, Largueta, Marcona, Mollar, and a commercial mixture of varieties) to study the influence of almond variety in the properties of injected biodegradable parts. The different AS varieties are analysed by means of Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD). The biocomposites are prepared in a twin-screw extruder and characterized in terms of their mechanical (tensile, flexural, Charpy impact, and hardness tests) and thermal properties (differential scanning calorimetry (DSC) and TGA). Despite observing differences in the chemical composition of the individual varieties with respect to the commercial mixture, the results obtained from the mechanical characterisation of the biocomposites do not present significant differences between the diverse varieties used. From these results, it was concluded that the most recommended option is to work with the commercial mixture of almond shell varieties, as it is easier and cheaper to acquire.

Síndrome de twiddler en paciente con trastorno obsesivo compulsivo tratado mediante estimulación cerebral profunda / Twiddler’s syndrome in a patient with obsessive-compulsive disorder treated with deep brain stimulation

El síndrome de twiddler es una extraña complicación relacionada con los dispositivos implantables de estimulación eléctrica. Descrito por primera vez en un paciente portador de marcapasos, es una complicación conocida en el ámbito de la cardiología, aunque no lo es tanto en el mundo de la neurocirugía, donde se ha descrito en relación con dispositivos de estimulación cerebral profunda. Se caracteriza por la manipulación, ya sea consciente, ya inconsciente, del generador de tales dispositivos, lo que origina el giro de este sobre sí mismo, lo que ocasiona el trenzado del cableado de estos sistemas, pudiendo provocar su rotura o bien el desplazamiento de los electrodos intracraneales. Describimos un caso de síndrome de twiddler en un paciente tratado mediante estimulación cerebral profunda para el trastorno obsesivo compulsivo que, tras una buena respuesta inicial, presenta un deterioro clínico, apreciándose en las radiografías de control del sistema el giro del cableado y el desplazamiento de los electrodos intracraneales

Twiddler's syndrome is a rare complication associated with implantable electrical stimulation devices. First described in a patient with a pacemaker, it is a known complication in the field of cardiology. However, it is not so recognised in the world of neurosurgery, in which it has been described in relation to deep brain stimulation (DBS) devices. Characterised by manipulating either consciously or unconsciously the generator of such devices, which causes it to rotate on itself, the syndrome causes the coiling of the wiring of these systems and can lead to their rupture or the displacement of intracranial electrodes. We describe a case of twiddler's syndrome in a patient treated with DBS for obsessive-compulsive disorder, in which clinical deterioration presented after a good initial response. Control radiographs revealed rotation of the wiring system and displacement of the intracranial electrodes

[Twiddler's syndrome in a patient with obsessive-compulsive disorder treated with deep brain stimulation]. / Síndrome de twiddler en paciente con trastorno obsesivo compulsivo tratado mediante estimulación cerebral profunda.

Twiddler's syndrome is a rare complication associated with implantable electrical stimulation devices. First described in a patient with a pacemaker, it is a known complication in the field of cardiology. However, it is not so recognised in the world of neurosurgery, in which it has been described in relation to deep brain stimulation (DBS) devices. Characterised by manipulating either consciously or unconsciously the generator of such devices, which causes it to rotate on itself, the syndrome causes the coiling of the wiring of these systems and can lead to their rupture or the displacement of intracranial electrodes. We describe a case of twiddler's syndrome in a patient treated with DBS for obsessive-compulsive disorder, in which clinical deterioration presented after a good initial response. Control radiographs revealed rotation of the wiring system and displacement of the intracranial electrodes.

Therapeutic monitoring of escitalopram by dexamethasone suppression test.

INTRODUCTION: Depression is associated with a dysfunction of regulation of the hypothalamic-pituitary-adrenal, HPA, which is reflected in the alteration of the dexamethasone suppression test, DST. Escitalopram and other SSRIs decrease the HPA axis response to the DST, beeing the aim of this study validate the DST as a surrogate marker of central serotonergic activity in the treatment with escitalopram and its application to the calculation of the dosage regimens. METHODOLOGY: Prospective observational study on 29 patients, upon whom was performed the DST-test with 0.25 mg of Dexamethasone and subsequent genetic analysis of CYP2C19 by Progenika PHARMAchip test. RESULTS: The range of plasma cortisol levels post-DTS associated with each phenotypic group were: PM phenotype= 0.6 to 1.7 mcg/dl, IM phenotype= 1.2 to 3.5 mcg/dl and EM phenotype = 4.8 to 13.2 mcg/dl, being carried out the dose titration and correspondng, respectively, the following dose regimens: 3-4 mg/day, 5-8 mg/day and 10-31 mg/day. COCLUSIONES: It has been shown that the DST test can be used as a surrogate marker of drug response to escitalopram and as a tool for dose adjustment, providing significant data on different phenotypes of CYP2C19 metabolizers.

Monitorización terapéutica de escitalopram mediante el test de supresión con dexametasona / Therapeutic monitoring of escitalopram by dexamethasone suppression test

Introducción. La depresión está asociada a una disfunción de la regulación del eje hipotálamo-pituitario-adrenal, HPA, que se refleja en la alteración del test de supresión con Dexametasona, DST. Escitalopram y otros ISRS disminuyen la respuesta del eje HPA en el DST, siendo el objetivo del presente trabajo la validación del DST como marcador subrogado de la actividad serotoninergica central en los tratamientos con escitalopram y su aplicación al cálculo de sus regimenes nosológicos. Metodología. Estudio prospectivo observacional sobre 29pacientes, a los que se realizo el DST con 0,25 mg de Dexametasona y posterior análisis genético del CYP2C19 mediante test PHARMA chip de Progenika. Resultados. El rango de valores de cortisol plasmático post-DTS asociados a cada grupo fenotipico fueron: fenotipo PM=0,6-1,7 mcg/dl, fenotipo IM=1,2-3,5 mcg/dl y para el fenotipo EM=4,8-13,2 mcg/dl, realizándose el ajuste nosológico y correspondiéndoles, respectivamente, las siguiente dosis: 3-4 mg/día, 5-8 mg/día y 10-31 mg/día. Conclusiones. Se ha comprobado que el DST test puede utilizarse como marcador subrogado de la respuesta farmacológica al escitalopram y como instrumento para su ajuste nosológico, proporcionando datos significativos sobre distintos fenotipos metabolizadores del CYP2C19 (AU)

Introduction. Depression is associated with a dysfunction of regulation of the hypothalamic-pituitary-adrenal, HPA, which is reflected in the alteration of the dexamethasone suppression test, DST. Escitalopram and other SSRIs decrease the HPA axis response to the DST, beeing the aim of this study validate the DST as a surrogate marker of central serotonergic activity in the treatment with escitalopram and its application to the calculation of the dosage regimens. Methodology. Prospective observational study on 29patients, upon whom was performed the DST-test with0.25 mg of Dexamethasone and subsequent genetic analysis of CYP2C19 by Progenika PHARMA chip test. Results. The range of plasma cortisol levels post-DTS associated with each phenotypic group were: PM phenotype=0.6 to 1.7 mcg/dl, IM phenotype= 1.2 to 3.5 mcg/dl and EM phenotype = 4.8 to 13.2 mcg/dl, being carried out the dosetitration and corresponding, respectively, the following dose regimens: 3-4 mg/day, 5-8 mg/day and 10-31 mg/day. Conclusions. It has been shown that the DST test can be used as a surrogate marker of drug response to escitalopram and as a tool for dose adjustment, providing significant data on different phenotypes of CYP2C19 metabolizers (AU)

Long-term outcomes of IgA nephropathy presenting with minimal or no proteinuria.

The long-term outcome of patients with IgA nephropathy who present with normal renal function, microscopic hematuria, and minimal or no proteinuria is not well described. Here, we studied 141 Caucasian patients with biopsy-proven IgA nephropathy who had minor abnormalities at presentation and a median follow-up of 108 months. None of the patients received corticosteroids or immunosuppressants. We reviewed renal biopsies using the Oxford classification criteria. In this sample, 46 (32%) patients had mesangial proliferation, whereas endocapillary proliferation, focal glomerulosclerosis, and tubulointerstitial abnormalities were uncommon. Serum creatinine increases >50% and >100% were observed in five (3.5%) patients and one (0.7%) patient, respectively; no patients developed ESRD. After 10, 15, and 20 years, 96.7%, 91.9%, and 91.9% of patients maintained serum creatinine values less than a 50% increase, respectively. Using Cox proportional hazards regression, the presence of segmental glomerulosclerosis was the only factor that significantly associated with a >50% increase in serum creatinine. Clinical remission occurred in 53 (37.5%) patients after a median of 48 months. Proteinuria>0.5 and >1.0 g/24 h developed in 21 (14.9%) and 6 (4.2%) patients, respectively. Median proteinuria at the end of follow-up was 0.1 g/24 h, with 41 (29.1%) patients having no proteinuria. At presentation, 23 (16.3%) patients were hypertensive compared with 30 (21.3%) patients at the end of follow-up; 59 (41.8%) patients were treated with renin-angiotensin blockers because of hypertension or increasing proteinuria. In summary, the long-term prognosis for Caucasian patients with IgA nephropathy who present with minor urinary abnormalities and normal renal function is excellent.

¿Es útil la concentración plasmática de tiroxina libre como biomarcador para el cálculo de regímenes posológicos de sales de litio? / No disponible

No disponible

[Polymyositis and interstitial lung disease with a favorable response to corticosteroids and methotrexate]. / Polimiositis y afectación pulmonar intersticial con buena respuesta a glucocorticoides y metotrexato.

Polymyositis is a rare collagen disease that can involve the lungs. Between 5% and 30% of patients with polymyositis present interstitial lung disease at diagnosis or during the course of disease. Onset is usually insidious and involves dyspnea and nonproductive cough. Several histopathological findings are associated with polymyositis and the most common is nonspecific interstitial pneumonia. The prognosis of interstitial lung disease associated with polymyositis is better than that of idiopathic pulmonary fibrosis, since most patients respond to treatment with corticosteroids and immunosuppressants. We report the case of a 60-year-old woman with dyspnea and muscle weakness who was diagnosed with polymyositis and interstitial lung disease (radiography indicated possible nonspecific interstitial pneumonia). The patient responded well to prednisone and methotrexate.

Polimiositis y afectación pulmonar intersticial con buena respuesta a glucocorticoides y metotrexato / Polymyositis and interstitial lung disease with a favorable response to corticosteroids and methotrexate

La polimiositis es una colagenopatía rara, que puede afectar al pulmón. Entre un 5 y un 30% de los pacientes con polimiositis presenta una enfermedad pulmonar intersticial en el momento del diagnóstico o durante el curso de la enfermedad. El inicio suele ser insidioso en forma de disnea y tos seca. Son varias las entidades histopatológicas que se asocian a polimiositis, de las cuales la más frecuente es la neumonía intersticial no específica. El pronóstico de la enfermedad pulmonar intersticial difusa asociada a polimiositis es mejor que el de la fibrosis pulmonar idiopática, ya que la mayoría de los pacientes responde al tratamiento con glucocorticoides e inmunodepresores. Presentamos el caso clínico de una mujer de 60 años con síntomas de disnea y debilidad muscular, a quien se diagnosticó de polimiositis y enfermedad pulmonar intersticial difusa (posible neumonía intersticial no específica por hallazgos radiológicos), y que mostró buena respuesta al tratamiento con prednisona y metotrexato

Polymyositis is a rare collagen disease that can involve the lungs. Between 5% and 30% of patients with polymyositis present interstitial lung disease at diagnosis or during the course of disease. Onset is usually insidious and involves dyspnea and nonproductive cough. Several histopathological findings are associated with polymyositis and the most common is nonspecific interstitial pneumonia. The prognosis of interstitial lung disease associated with polymyositis is better than that of idiopathic pulmonary fibrosis, since most patients respond to treatment with corticosteroids and immunosuppressants. We report the case of a 60-year-old woman with dyspnea and muscle weakness who was diagnosed with polymyositis and interstitial lung disease (radiography indicated possible nonspecific interstitial pneumonia). The patient responded well to prednisone and methotrexate

Prevention of cancer in the upper gastrointestinal tract with COX-inhibition. Still an option?

Epidemiological studies have shown that the regular use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with a reduction of gastrointestinal cancer risk. Since up-regulation of COX-2 has been reported in different stages of the esophageal and gastric carcinogenic sequence, the cyclooxygenase-2 selective inhibitors (COXIBs) were considered a good alternative to traditional NSAIDs since they cause less injury to the gastrointestinal mucosa. However, recent chemoprevention trial data reporting an increased risk of cardiovascular events have raised serious concerns on the safety of COXIBs in chemoprevention strategies. Moreover, low expression of COX-2 has been reported in a subset of gastrointestinal cancers due to COX-2 methylation, indicating that these patients could be less responsive to treatment by specific COX-2 inhibitors. Furthermore, the COX-1 isoform may have a potential role in the angiogenic process associated with esophageal adenocarcinoma, which suggests that inhibition of COX-1 may be another effective therapeutic target in upper gastrointestinal cancer. Finally, lipoxygenase-derived products may be increased following COX-inhibition due to shunting of the arachidonic acid metabolism. Specifically, the 5-LOX pathway seems to be relevant in gastrointestinal cancer development. Taken together, these data indicate that a re-evaluation of potential chemoprevention strategies for cancers of the upper gastrointestinal tract needs to be considered.

Effects of selective PGE2 receptor antagonists in esophageal adenocarcinoma cells derived from Barrett's esophagus.

Accumulating evidence suggests that COX-2-derived prostaglandin E(2) (PGE(2)) plays an important role in esophageal adenocarcinogenesis. Recently, PGE(2) receptors (EP) have been shown to be involved in colon cancer development. Since it is not known which receptors regulate PGE(2) signals in esophageal adenocarcinoma, we investigated the role of EP receptors using a human Barrett's-derived esophageal adenocarcinoma cell line (OE33). OE33 cells expressed COX-1, COX-2, EP(1), EP(2) and EP(4) but not EP(3) receptors as determined by real time RT-PCR and Western-blot. Treatment with 5-aza-dC restored expression, suggesting that hypermethylation is involved in EP(3) downregulation. Endogenous PGE(2) production was mainly due to COX-2, since this was significantly suppressed with COX-2 inhibitors (NS-398 and SC-58125), but not COX-1 inhibitors (SC-560). Cell proliferation ((3)H-thymidine uptake) was significantly inhibited by NS-398 and SC-58125, the EP(1) antagonist SC-51322, AH6809 (EP(1)/EP(2) antagonist), and the EP(4) antagonist AH23848B, but was not affected by exogenous PGE(2). However, treatment with the selective EP(2) agonist Butaprost or 16,16-dimethylPGE(2) significantly inhibited butyrate-induced apoptosis and stimulated OE33 cell migration. The effect of exogenous PGE(2) on migration was attenuated when cells were first treated with EP(1) and EP(4) antagonists. These findings suggest a potential role for EP selective antagonists in the treatment of esophageal adenocarcinoma.

Estudio de pacientes pediátricos con toxoplasmosis / Study about pediatric patients with toxoplasmosis

Se estudiaron 64 niños con diagnósticos clínico - laboratorial de toxoplasmosis en el lapso comprendido entre enero de 1983 y junio de 1985. Utilizamos como exámines complementarios el dosaje de IgG e IgM específica antitoxoplásmica, fondo de ojo, y cunado fue necesario, radiografía de craneo (de frente y perfil). El 75% de los integrantes de nuestra causística tenían sus domicilios fijados en San Miguel de Tucumán, se observó un predominio de 2:1 del sexo masculino. Se constató un 70,31% de formas linfadénicas, 25% de formas oculares, disminuyendo en forma marcada la incidencia en la casuística de las restantes formas clínicas de esta patología

Estudio de pacientes pediátricos con toxoplasmosis / Study about pediatric patients with toxoplasmosis

Se estudiaron 64 niños con diagnósticos clínico - laboratorial de toxoplasmosis en el lapso comprendido entre enero de 1983 y junio de 1985. Utilizamos como exámines complementarios el dosaje de IgG e IgM específica antitoxoplásmica, fondo de ojo, y cunado fue necesario, radiografía de craneo (de frente y perfil). El 75% de los integrantes de nuestra causística tenían sus domicilios fijados en San Miguel de Tucumán, se observó un predominio de 2:1 del sexo masculino. Se constató un 70,31% de formas linfadénicas, 25% de formas oculares, disminuyendo en forma marcada la incidencia en la casuística de las restantes formas clínicas de esta patología (AU)