Reclassification of Cybistrinae Sharp, 1880 in the Neotropical Region (Coleoptera, Adephaga, Dytiscidae), with description of new taxa.

The classification of the Neotropical Cybistrinae Sharp, 1880 (Coleoptera: Adephaga: Dytiscidae) is extensively revised based on a phylogenetic analysis of morphological features of the group. A new genus, Nilssondytesgen. nov. is described for a unique new species, Nilssondytesdiversussp. nov. from Venezuela. The New World genus, Megadytes Sharp, 1882, with several subgenera, was found to not be monophyletic. The type species of Megadytes, Dytiscuslatus Fabricius, 1801 and the species Cybisterparvus Trémouilles, 1984 were found to be monophyletic together, and phylogenetically more closely related to Cybister Curtis, 1827 than to other species assigned to Megadytes sensu stricto, which were found to also be monophyletic. The name Megadytes is here restricted to include only Megadyteslatus and Megadytesparvus. These two species assigned to this newly restricted genus concept are reviewed and diagnosed. A new genus, Metaxydytesgen. nov., is erected to include all the other species currently assigned to Megadytes sensu stricto. The current subgenus names assigned to Megadytes, Bifurcitus Brinck, 1945, Paramegadytes Trémouilles & Bachmann, 1980, and Trifurcitus Brinck, 1945, are elevated to genus rank since they are variously paraphyletic. The two species assigned to Cybister (Neocybister) Miller, Bergsten & Whiting, 2007, Cybister (Neocybister) festae Griffini, 1895, and Cybister (Neocybister) puncticollis (Brullé, 1837) re reviewed and diagnosed with the former redescribed and its type specimens considered for the first time since its description. Another evidently new species and possible new genus, Megadytes species, IR57 (Ribera et al. 2008), from Peru, is also characterized, but not formally treated because of lack of important data for the single, partial specimen. Diagnostic features are illustrated for the entire group.

ResumenLa clasificación de Cybistrinae Sharp, 1880 neotropicales (Coleoptera: Adephaga: Dytiscidae) se revisa ampliamente con base en un análisis filogenético de características morfológicas del grupo. Un nuevo género, Nilssondytesgen. nov. se describe para la única nueva especie Nilssondytesdiversussp. nov. de Venezuela. Se encontró que el género, Megadytes Sharp, 1882, del Nuevo Mundo y con varios subgéneros, no es monofilético. Se encontró que la especie tipo de Megadytes, Dytiscuslatus Fabricius, 1801 y la especie Cybisterparvus Trémouilles, 1984 forman un grupo monofilético y filogenéticamente más estrechamente relacionado con Cybister Curtis, 1827 que con otras especies asignadas a Megadytes sensu stricto, que se encontró que también forman un grupo monofilético. El nombre Megadytes se restringe aquí para incluir solo a Megadyteslatus y Megadytesparvus. Se revisan y diagnostican estas dos especies asignadas a este nuevo concepto restringido del género. Un nuevo nombre, Metaxydytesgen. nov., se erige para incluir a todas las demás especies actualmente asignadas a Megadytes sensu stricto. Los nombres subgenéricos actuales asignados a Megadytes, Bifurcitus Brinck, 1945, Paramegadytes Trémouilles y Bachmann, 1980 y Trifurcitus Brinck, 1945, se elevan al rango de género, nuevo estado, ya que son parafiléticos de diversas formas. Se revisan y diagnostican las dos especies asignadas a Cybister (Neocybister) Miller, Bergsten y Whiting, 2007, Cybister (Neocybister) festae Griffini, 1895 y Cybister (Neocybister) puncticollis, redescribiendo la primera y considerando sus especímenes tipo por primera vez desde su descripción. Otra especie evidentemente nueva y posible nuevo género, Megadytes, IR57 (Ribera et al. 2008), de Perú, también se caracteriza, pero no se trata formalmente debido a la falta de datos importantes para el único espécimen parcial. Las características diagnósticas se ilustran para todo el grupo.

FT-MIR-ATR Associated with Chemometrics Methods: A Preliminary Analysis of Deterioration State of Brazil Nut Oil.

Brazil nut oil is highly valued in the food, cosmetic, chemical, and pharmaceutical industries, as well as other sectors of the economy. This work aims to use the Fourier transform infrared (FTIR) technique associated with partial least squares regression (PLSR) and principal component analysis (PCA) to demonstrate that these methods can be used in a prior and rapid analysis in quality control. Natural oils were extracted and stored for chemical analysis. PCA presented two groups regarding the state of degradation, subdivided into super-degraded and partially degraded groups in 99.88% of the explained variance. The applied PLS reported an acidity index (AI) prediction model with root mean square error of calibration (RMSEC) = 1.8564, root mean square error of cross-validation (REMSECV) = 4.2641, root mean square error of prediction (RMSEP) = 2.1491, R2cal (calibration correlation coefficient) equal to 0.9679, R2val (validation correlation coefficient) equal to 0.8474, and R2pred (prediction correlation coefficient) equal to 0, 8468. The peroxide index (PI) prediction model showed RMSEC = 0.0005, REMSECV = 0.0016, RMSEP = 0.00079, calibration R2 equal to 0.9670, cross-validation R2 equal to 0.7149, and R2 of prediction equal to 0.9099. The physical-chemical analyses identified that five samples fit in the food sector and the others fit in other sectors of the economy. In this way, the preliminary monitoring of the state of degradation was reported, and the prediction models of the peroxide and acidity indexes in Brazil nut oil for quality control were determined.

A 3D-Printed Ceramics Innovative Firing Technique: A Numerical and Experimental Study.

Additive manufacturing (AM), also known as three-dimensional (3D) printing, allows the fabrication of complex parts, which are impossible or very expensive to produce using traditional processes. That is the case for dinnerware and artworks (stoneware, porcelain and clay-based products). After the piece is formed, the greenware is fired at high temperatures so that these pieces gain its mechanical strength and aesthetics. The conventional (gas or resistive heating elements) firing usually requires long heating cycles, presently requiring around 10 h to reach temperatures as high as 1200 °C. Searching for faster processes, 3D-printed stoneware were fired using microwave (MW) radiation. The pieces were fired within 10% of the conventional processing time. The temperature were controlled using a pyrometer and monitored using Process Temperature Control Rings (PTCRs). An error of 1.25% was calculated between the PTCR (1207 ± 15 °C) and the pyrometer (1200 °C). Microwave-fast-fired pieces show similar mechanical strength to the references and to the electrically fast-fired pieces (41, 46 and 34 (N/mm2), respectively), presenting aesthetic features closer to the reference. Total porosities of ~4%, ~5% and ~9% were determined for microwave, electrically fast-fired and reference samples. Numerical studies have shown to be essential to better understand and improve the firing process using microwave radiation. In summary, microwave heating can be employed as an alternative to stoneware conventional firing methods, not compromising the quality and features of the processed pieces, and with gains in the heating time.

Trends in the Use of Lipases: A Systematic Review and Bibliometric Analysis.

Scientific mapping using bibliometric data network analysis was applied to analyze research works related to lipases and their industrial applications, evaluating the current state of research, challenges, and opportunities in the use of these biocatalysts, based on the evaluation of a large number of publications on the topic, allowing a comprehensive systematic data analysis, which had not yet been conducted in relation to studies specifically covering lipases and their industrial applications. Thus, studies involving lipase enzymes published from 2018 to 2022 were accessed from the Web of Science database. The extracted records result in the analysis of terms of bibliographic compatibility among the articles, co-occurrence of keywords, and co-citation of journals using the VOSviewer algorithm in the construction of bibliometric maps. This systematic review analysis of 357 documents, including original and review articles, revealed studies inspired by lipase enzymes in the research period, showing that the development of research, together with different areas of knowledge, presents good results related to the applications of lipases, due to information synchronization. Furthermore, this review showed the main challenges in lipase applications regarding increased production and operational stability; establishing well-defined evaluation criteria, such as cultivation conditions, activity, biocatalyst stability, type of support and reactor; thermodynamic studies; reuse cycles; and it can assist in defining goals for the development of successful large-scale applications, showing several points for improvement of future studies on lipase enzymes.

Mairá-Potato (Casimirella sp.): Botanical, Food, Pharmacological, and Phytochemical Aspects.

Millions of people in the world live in food insecurity, so identifying a tuber with characteristics capable of meeting the demand for food and also identifying active compounds that can be used to minimize harm to human health is of great value. The aim was to carry out a review based on systematic review tools and the main objective was to seek information on botanical, food, pharmacological, and phytochemical aspects of Casimirella sp. and propose possible applications. This review showed papers that addressed botanical, food, pharmacological, and phytochemical aspects of the Mairá-potato and presented suggestions for using this tuber allied to the information described in the works found in the Google Academic, Scielo, Science Direct, Scopus, PubMed, and Web of Science databases. This review synthesized knowledge about the Mairá-potato that can contribute to the direction of further research on the suggested technological applications, both on the use of this tuber as a polymeric material and its use as biomaterial, encapsulation, bioactive use, and 3D printing, because this work collected information about this non-conventional food plant (PANC) that shows great potential for use in various areas of study.

Fetal neurosurgery.

Among fetal surgical procedures, neurosurgery stands out due to the number of cases and the possibility of developing new procedures that can be performed in the fetal period. To perform fetal neurosurgical procedures, there is a need for specialized centers that have experts in the diagnosis of fetal pathologies and a highly complex obstetrics service with specialized maternal-fetal teams associated with a pediatric neurosurgery center with expertise in the diverse pathologies of the fetus and the central nervous system that offers multidisciplinary follow-up during postnatal life. Services that do not have these characteristics should refer their patients to these centers to obtain better treatment results. It is essential that the fetal neurosurgical procedure be performed by a pediatric neurosurgeon with extensive experience, as he will be responsible for monitoring these patients in the postnatal period and for several years. The objective of this manuscript is to demonstrate the diagnostic and treatment possibilities, in the fetal period, of some neurosurgical diseases such as hydrocephalus, tumors, occipital encephalocele, and myelomeningocele.

Microbial Lipid Based Biorefinery Concepts: A Review of Status and Prospects.

The use of lignocellulosic biomass as a raw material for the production of lipids has gained increasing attention, especially in recent years when the use of food in the production of biofuels has become a current technology. Thus, the competition for raw materials for both uses has brought the need to create technological alternatives to reduce this competition that could generate a reduction in the volume of food offered and a consequent commercial increase in the value of food. Furthermore, the use of microbial oils has been studied in many industrial branches, from the generation of renewable energy to the obtainment of several value-added products in the pharmaceutical and food industries. Thus, this review provides an overview of the feasibility and challenges observed in the production of microbial lipids through the use of lignocellulosic biomass in a biorefinery. Topics covered include biorefining technology, the microbial oil market, oily microorganisms, mechanisms involved in lipid-producing microbial metabolism, strain development, processes, lignocellulosic lipids, technical drawbacks, and lipid recovery.

Crude Enzyme Concentrate of Filamentous Fungus Hydrolyzed Chitosan to Obtain Oligomers of Different Sizes.

Chitosan is a non-cytotoxic polysaccharide that, upon hydrolysis, releases oligomers of different sizes that may have antioxidant, antimicrobial activity and the inhibition of cancer cell growth, among other applications. It is, therefore, a hydrolysis process with great biotechnological relevance. Thus, this study aims to use a crude enzyme concentrate (CEC) produced by a filamentous fungus to obtain oligomers with different molecular weights. The microorganism was cultivated in a liquid medium (modified Czapeck-with carboxymethylcellulose as enzyme inducer). The enzymes present in the CEC were identified by LC-MS/MS, with an emphasis on cellobiohydrolase (E.C 3.2.1.91). The fungus of the Aspergillus genus was identified by amplifying the ITS1-5.8S-ITS2 rDNA region and metaproteomic analysis, where the excreted enzymes were identified with sequence coverage greater than 84% to A. nidulans. Chitosan hydrolysis assays compared the CEC with the commercial enzyme (Celluclast 1.5 L®). The ability to reduce the initial molecular mass of chitosan by 47.80, 75.24, and 93.26% after 2.0, 5.0, and 24 h of reaction, respectively, was observed. FTIR analyses revealed lower absorbance of chitosan oligomers' spectral signals, and their crystallinity was reduced after 3 h of hydrolysis. Based on these results, we can conclude that the crude enzyme concentrate showed a significant technological potential for obtaining chitosan oligomers of different sizes.

Jambu Flower Extract (Acmella oleracea) Increases the Antioxidant Potential of Beer with a Reduced Alcohol Content.

Craft beers with different sensory perceptions have received the attention of more demanding consumers. In this sense, the application of plant extracts as brewing adjuncts is being increasingly studied. Allied with these perspectives is the consumption of lower alcoholic beverages, which also represents the desire for a market niche that has been growing gradually. The present work aimed to produce craft lager beer with the addition of plant extract and reduced alcohol content by partial replacement of malt with malt bagasse. The physical-chemical analyzes of the beer produced showed that it was possible to reduce the alcohol content by 40.5% compared to the control sample. In addition, an extract of Acmella oleracea (Jambu) obtained by supercritical extraction was added to increase the beer's antioxidant capacity. The ABTS, DPPH, and ORAC methods evaluated the antioxidant capacity. These assays were performed again after six months of storage. The quantification and identification of the significant substance in the extract (spilanthol) were performed using Gas Chromatography (GC-FID), Thin Layer Chromatography (TLC), and Attenuated Total Reflectance Infrared Spectroscopy (FTIR-ATR). The results showed significant increases in antioxidant activity compared to the sample without extract. This positive aspect opens a perspective for using jambu flower extract as a prominent antioxidant adjunct in beer.

Elaboration and Characterization of Natural Deep Eutectic Solvents (NADESs): Application in the Extraction of Phenolic Compounds from pitaya.

In this paper, natural deep eutectic solvents (NADESs) with lactic acid, glycine, ammonium acetate, sodium acetate, and choline chloride were prepared with and without the addition of water. NADES formation was evaluated using FTIR and Raman, where hydrogen bonds were identified between the hydroxyl group of lactic acid and the amino and carboxyl groups of glycine. Acetate and ammonium ions were also identified as forming bonds with lactic acid. The addition of water did not cause changes in the vibrational modes of the FTIR and Raman spectra but contributed to a reduction in NADES viscosity and density. Viscosity ranged from 0.335 to 0.017 Pa s-1, and density ranged from 1.159 to 0.785 g mL-1. The best results for the extraction of phenolic compounds from pitaya (dragon fruit) were achieved with an organic solvent (450. 41 mg 100 g-1 dry bases-db) in comparison to NADESs lactic acid:glycine (193.18 mg 100 g-1 db) and lactic acid:ammonium acetate (186.08 mg 100 g-1 db). The antioxidant activity of the extracts obtained with the NADESs was not statistically different from that of the extract obtained with organic solvents.

GLP-1 Receptor Agonists in Neurodegeneration: Neurovascular Unit in the Spotlight.

Defects in brain energy metabolism and proteopathic stress are implicated in age-related degenerative neuronopathies, exemplified by Alzheimer's disease (AD) and Parkinson's disease (PD). As the currently available drug regimens largely aim to mitigate cognitive decline and/or motor symptoms, there is a dire need for mechanism-based therapies that can be used to improve neuronal function and potentially slow down the underlying disease processes. In this context, a new class of pharmacological agents that achieve improved glycaemic control via the glucagon-like peptide 1 (GLP-1) receptor has attracted significant attention as putative neuroprotective agents. The experimental evidence supporting their potential therapeutic value, mainly derived from cellular and animal models of AD and PD, has been discussed in several research reports and review opinions recently. In this review article, we discuss the pathological relevance of derangements in the neurovascular unit and the significance of neuron-glia metabolic coupling in AD and PD. With this context, we also discuss some unresolved questions with regard to the potential benefits of GLP-1 agonists on the neurovascular unit (NVU), and provide examples of novel experimental paradigms that could be useful in improving our understanding regarding the neuroprotective mode of action associated with these agents.

Correction to: Prodromal neuroinvasion of pathological α-synuclein in brainstem reticular nuclei and white matter lesions in a model of α-synucleinopathy.

[This corrects the article DOI: 10.1093/braincomms/fcab104.].

Adsorption of Cu (II) Ions Present in the Distilled Beverage (Sugar Cane Spirit) Using Chitosan Derived from the Shrimp Shell.

Cachaça (sugar cane spirit) is a typically Brazilian distilled beverage. Copper ions can be present in craft beverages despite their acceptance in the national and international market. This study aims to evaluate the efficiency of chitosan as an adsorbent in removing copper (II) from cachaça. The structural characteristics of the obtained chitosan and the effect of adsorbed copper were evaluated by Fourier Transform Infrared Spectroscopy (ATR-FTIR), viscosimetry, X-ray diffraction (XRD), and scanning electron microscopy (SEM). The deacetylation reaction from chitin (shrimp shell) resulted in chitosan with a deacetylation degree of 88.9% (potentiometric titration) and 86.9% (FTIR), low crystallinity, and an estimated molecular weight of 162.96 kDa. The copper reduction rate was 84.09% evaluated by spectrophotometric titration and microwave-induced plasma optical emission spectrometry (MIP-OES). The amine groups of chitosan had adsorption affinity with copper ions, and the kinetic analysis showed a better fit of the data by the Elovich equation, suggesting that the chemosorption mechanism controlled the kinetic process. The results suggest that chitosan has the potential to improve the quality and safety of cachaça.

Passive Immunization in Alpha-Synuclein Preclinical Animal Models.

Alpha-synucleinopathies include Parkinson's disease, dementia with Lewy bodies, pure autonomic failure and multiple system atrophy. These are all progressive neurodegenerative diseases that are characterized by pathological misfolding and accumulation of the protein alpha-synuclein (αsyn) in neurons, axons or glial cells in the brain, but also in other organs. The abnormal accumulation and propagation of pathogenic αsyn across the autonomic connectome is associated with progressive loss of neurons in the brain and peripheral organs, resulting in motor and non-motor symptoms. To date, no cure is available for synucleinopathies, and therapy is limited to symptomatic treatment of motor and non-motor symptoms upon diagnosis. Recent advances using passive immunization that target different αsyn structures show great potential to block disease progression in rodent studies of synucleinopathies. However, passive immunotherapy in clinical trials has been proven safe but less effective than in preclinical conditions. Here we review current achievements of passive immunotherapy in animal models of synucleinopathies. Furthermore, we propose new research strategies to increase translational outcome in patient studies, (1) by using antibodies against immature conformations of pathogenic αsyn (monomers, post-translationally modified monomers, oligomers and protofibrils) and (2) by focusing treatment on body-first synucleinopathies where damage in the brain is still limited and effective immunization could potentially stop disease progression by blocking the spread of pathogenic αsyn from peripheral organs to the brain.

The diagnostic accuracy of MRI in determining the relations between paraclinoid aneurysms and the cavernous sinus.

PURPOSE: The location of paraclinoid aneurysms is determinant for evaluation of its intradural compartment and risk of SAH after rupture. Advanced MRI techniques have provided clear visualization of the distal dural ring (DDR) to determine whether an aneurysm is intracavernous, transitional or intradural for decision-making. We analyzed the diagnostic accuracy of MRI in predicting whether a paraclinoid aneurysm is intracavernous, transitional or intradural. METHODS: We conducted a prospective cohort between January 2014 and December 2018. Patients with paraclinoid aneurysms underwent 3D fast spin-echo MRI sequence before surgical treatment. The DDR was the landmark for MRI characterization of the aneurysms as follow: (i) Intradural; (ii) Transitional; and (iii) Intracavernous. The MRI sensitivity, specificity, positive and negative likelihood ratios were determined compared to the intraoperative findings. We also evaluated the intertechnique agreement using the Cohen's kappa coefficient (κ) for dichotomous classifications (cavernous vs non-cavernous). RESULTS: Twenty patients were included in the cohort. The accuracy of MRI showed a sensitivity of 86.7% (95%CI:59.5-98.3) and specificity of 90.0% (95%CI:55.5-99.8). Analyzing only patients without history of SAH, accuracy test improved with a sensitivity of 92.3% (95%CI:63.9-99.8) and specificity reached 100% (95%CI: 63-100). Values of Cohen's kappa (κ), intertechnique agreement was considered substantial for dichotomous classifications (κ = 0.754; p < 0.001). For patients without previous SAH, intertechnique agreement was even more coincident for the dichotomous classification (κ = 0.901; p < 0.001). CONCLUSION: 3D fast spin-echo MRI sequence is a reliable and useful technique for determining the location of paraclinoid aneurysms in relation to the cavernous sinus, particularly for patients with no history of SAH.

Impact of surgery on ambulatory status in patients with symptomatic neoplastic spinal cord compression in southern brazil / Impacto da cirurgia sobre a capacidade de ambulatória em pacientes com compressão neoplásica sintomática da medula espinalno sul do brasil / Impacto de la cirugía en la capacidad de ambulación en pacientes con compresión medular neoplásica sintomática en el sur de brasil

ABSTRACT Background: Spinal cord compression is a common complication of spine metastasis and multiple myeloma. About 30% of patients with cancer develop symptomatic spinal metastases during their illness. Prompt diagnosis and surgical treatment of these lesions, although palliative, are likely to reduce the morbidity and improve quality of life by improving ambulatory function. Study Design: Retrospective review of medical records. Objective: To evaluate postoperative functional recovery and the epidemiological profile of neoplastic spinal cord compression in two neurosurgical centers in southern Brazil. Methods: We retrospectively analyzed the data of all patients who underwent palliative surgery for symptomatic neoplastic spine lesion from metastatic cancer, in two neurosurgical centers, between January 2003 and July 2021. The variables age, sex, neurological status, histological type, affected segment, complications and length of hospitalization were analyzed. Results: A total of 82 patients were included. The lesions occurred in the thoracic spine in 60 cases. At admission, 95% of the patients had neurological deficits, most of which were Frankel C (37%). At histopathological analysis, breast cancer was the most common primary site. After surgery, the neurological status of 46 patients (56%) was reclassified according to the Frankel scale. Of these, 22 (47%) regained ambulatory capacity. Conclusion: Surgical treatment of metastatic spinal cord compression improved neurological status and ambulatory ability in our sample. Level of evidence II; Retrospective study.

RESUMO: Introdução: A compressão medular é uma complicação comum de metástases da coluna vertebral e de mieloma múltiplo. Cerca de 30% dos pacientes com câncer desenvolvem metástases sintomáticas na coluna no decorrer da doença. O diagnóstico imediato e o tratamento cirúrgico dessas lesões, embora paliativos, em geral reduzema morbidade e melhoram a qualidade de vidaao ampliar a capacidade de deambular. Desenho do estudo: Revisão retrospectiva de prontuários médicos. Objetivo: Avaliar a recuperação funcional pós-operatória e o perfil epidemiológico da compressão medular neoplásica em dois centros de neurocirurgia do sul do Brasil. Métodos: Analisamos retrospectivamente os dados de todos os pacientes submetidos à cirurgia paliativa de lesão neoplásica sintomática da coluna decorrente decâncer metastático, em dois centros neurocirúrgicos entre janeiro de 2003 e julho de 2021. Foram analisadas as variáveis idade, sexo, estado neurológico, tipo histológico, segmento acometido, complicações e tempo de internação. Resultados: Foram incluídos 82 pacientes no estudo. As lesões ocorreram na coluna torácica em 60 casos. À internação, 95% dos pacientes apresentavam déficits neurológicos, sendoa maioria classificada como Frankel C (37%). Na análise histopatológica, o câncer de mama foi o sítio primário mais comum. Depois da cirurgia, 46 pacientes (56%) tiveram o estado neurológico reclassificado pela escala de Frankel. Entre eles, 22 (47%) recuperaram a capacidade de deambular. Conclusões: O tratamento cirúrgico da compressão medular metastática melhorou o estado neurológico e a capacidade de deambulação em nossa amostra. Nível de evidência II; Estudo retrospectivo.

RESUMEN: Introducción: La compresión de la médula espinal es una complicación común de la metástasis de la columna vertebral y el mieloma múltiple. Aproximadamente el 30% de los pacientes con cáncer desarrollan metástasis espinales sintomáticas en el curso de la enfermedad. El diagnóstico precoz y el tratamiento quirúrgico de estas lesiones, aunque son paliativos, suelen reducir la morbilidad y mejor en lacalidad de vida al aumentar la de ambulación. Diseño del estudio: Revisión retrospectiva de registros médicos. Objetivo: Evaluarla recuperación funcional postoperatoria y el perfil epidemiológico de la compresión medular neoplásica en dos centros neuroquirúrgicos del sur de Brasil. Métodos: Analizamos retrospectivamente los datos de todos los pacientes sometidos a cirugía paliativa por lesión vertebral neoplásica sintomática por cáncer metastásico, en dos centros neuroquirúrgicos entre enero de 2003 y julio de 2021. Se analizaron las variables edad, sexo, estado neurológico, tipo histológico, segmento afectado, complicaciones y duración de la hospitalización. Resultados: Se incluyeron 82 pacientes en el estudio. Las lesiones se produjeron en la columna torácica en 60 casos. Al ingreso, el 95% de los pacientes presentaban déficits neurológicos y la mayoría de ellos eran clasificados como Frankel C (37%). En el análisis histopatológico, elcáncer de mama fue el sitio primario más común. Después de la cirugía, se reclasificó el estado neurológico de 46 pacientes (56%) por la escala de Frankel. Entre ellos, 22 (47%) recuperaron la capacidadde deambulación. Conclusiones: El tratamiento quirúrgico de la compresión medular metastásica mejoró el estado neurológico y la capacidad de deambulación en nuestra muestra. Nivel de evidencia II; Estudio retrospectivo.

Polo-like kinase 2 inhibition reduces serine-129 phosphorylation of physiological nuclear alpha-synuclein but not of the aggregated alpha-synuclein.

Accumulation of aggregated alpha-synuclein (α-syn) is believed to play a pivotal role in the pathophysiology of Parkinson's disease (PD) and other synucleinopathies. As a key constituent of Lewy pathology, more than 90% of α-syn in Lewy bodies is phosphorylated at serine-129 (pS129) and hence, it is used extensively as a marker for α-syn pathology. However, the exact role of pS129 remains controversial and the kinase(s) responsible for the phosphorylation have yet to be determined. In this study, we investigated the effect of Polo-like kinase 2 (PLK2) inhibition on formation of pS129 using an ex vivo organotypic brain slice model of synucleinopathy. Our data demonstrated that PLK2 inhibition has no effect on α-syn aggregation, pS129 or inter-neuronal spreading of the aggregated α-syn seen in the organotypic slices. Instead, PLK2 inhibition reduced the soluble pS129 level in the nuclei. The same finding was replicated in an in vivo mouse model of templated α-syn aggregation and in human dopaminergic neurons, suggesting that PLK2 is more likely to be involved in S129-phosphorylation of the soluble physiological fraction of α-syn. We also demonstrated that reduction of nuclear pS129 following PLK2 inhibition for a short time before sample collection improves the signal-to-noise ratio when quantifying pS129 aggregate pathology.

Production of Low Molecular Weight Chitosan and Chitooligosaccharides (COS): A Review.

Chitosan is a biopolymer with high added value, and its properties are related to its molecular weight. Thus, high molecular weight values provide low solubility of chitosan, presenting limitations in its use. Based on this, several studies have developed different hydrolysis methods to reduce the molecular weight of chitosan. Acid hydrolysis is still the most used method to obtain low molecular weight chitosan and chitooligosaccharides. However, the use of acids can generate environmental impacts. When different methods are combined, gamma radiation and microwave power intensity are the variables that most influence acid hydrolysis. Otherwise, in oxidative hydrolysis with hydrogen peroxide, a long time is the limiting factor. Thus, it was observed that the most efficient method is the association between the different hydrolysis methods mentioned. However, this alternative can increase the cost of the process. Enzymatic hydrolysis is the most studied method due to its environmental advantages and high specificity. However, hydrolysis time and process cost are factors that still limit industrial application. In addition, the enzymatic method has a limited association with other hydrolysis methods due to the sensitivity of the enzymes. Therefore, this article seeks to extensively review the variables that influence the main methods of hydrolysis: acid concentration, radiation intensity, potency, time, temperature, pH, and enzyme/substrate ratio, observing their influence on molecular weight, yield, and characteristic of the product.

The Prion-Like Spreading of Alpha-Synuclein in Parkinson's Disease: Update on Models and Hypotheses.

The pathological aggregation of the presynaptic protein α-synuclein (α-syn) and propagation through synaptically coupled neuroanatomical tracts is increasingly thought to underlie the pathophysiological progression of Parkinson's disease (PD) and related synucleinopathies. Although the precise molecular mechanisms responsible for the spreading of pathological α-syn accumulation in the CNS are not fully understood, growing evidence suggests that de novo α-syn misfolding and/or neuronal internalization of aggregated α-syn facilitates conformational templating of endogenous α-syn monomers in a mechanism reminiscent of prions. A refined understanding of the biochemical and cellular factors mediating the pathological neuron-to-neuron propagation of misfolded α-syn will potentially elucidate the etiology of PD and unravel novel targets for therapeutic intervention. Here, we discuss recent developments on the hypothesis regarding trans-synaptic propagation of α-syn pathology in the context of neuronal vulnerability and highlight the potential utility of novel experimental models of synucleinopathies.