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The increasing global demand for cement significantly impacts greenhouse gas emissions and resource consumption, necessitating sustainable alternatives. This study investigates fresh geopolymer (GP) pastes incorporating 20 wt.% of five industrial wastes-suction dust, red mud from alumina production, electro-filter dust, and extraction sludges from food supplement production and from partially stabilized industrial waste-as potential replacements for traditional cement. Consistent synthesis methods are used to prepare the geopolymers, which are characterized for their physicochemical, mechanical, and biological properties. Ionic conductivity and pH measurements together with integrity tests, thermogravimetry analysis (TGA), and leaching analysis are used to confirm the stability of the synthesized geopolymers. Fourier-transform Infrared (FT-IR) spectroscopy is used to follow geopolymerization occurrences. Results for ionic conductivity, pH, and integrity revealed that the synthesized GPs were macroscopically stable. TGA revealed that the main mass losses were ascribable to water dehydration and to water entrapped in the geopolymer networks. Only the GP filled with the powder of the red mud coming from alumina production experienced a mass loss of 23% due to a partial waste degradation. FT-IR showed a red shift in the main Si-O-(Si or Al) absorption band, indicating successful geopolymer network formations. Additionally, most of the GPs filled with the wastes exhibited higher compressive strength (37.8-58.5 MPa) compared to the control (22 MPa). Only the GP filled with the partially stabilized industrial waste had a lower mechanical strength as its structure was highly porous because of gas formation during geopolymerization reactions. Despite the high compressive strength (58.5 MPa) of the GP filled with suction dust waste, the concentration of Sb leached was 25 ppm, which limits its use. Eventually, all samples also demonstrated effective antimicrobial activity against Escherichia coli and Staphylococcus aureus due to the alkaline environment and the presence of metal cations able to react with the bacterial membranes. The findings revealed the possibility of recycling these wastes within several application fields.
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Goats are often affected by respiratory diseases and, despite ultrasonography can assess lung consolidations in several species, it is rarely used in these animals. So, this study evaluated the effectiveness of on-farm lung ultrasonography in detecting lung consolidations on 27 goats. The goats, scheduled for slaughter, underwent complete clinical examinations and lung ultrasonography. For the latter, both sides of the thorax were divided in four quadrants and examined using convex and linear probes before and after shaving the hair. Each quadrant was classified based on presence/absence of lung consolidation and maximum consolidation's depth (4-point scale: 0 healthy; 1 depth < 1 cm; 2 depth < 3 cm; 3 depth > 3 cm). The lungs were examined at necropsy, 66% of goats exhibited lung consolidations and sensitivity (83%-89%), specificity (100%), and κ coefficient values (0.67-0.72) were high with all techniques. An higher (p ≤ 0.01) percentage of class 1 lesions were found at necropsy compared to all the ultrasonographic techniques. All the ultrasonographic techniques effectively detected lung consolidation deeper than 1 cm. So, ultrasonography seems an effective tool for lung examination in goats with chronic pneumonia. The examination using the linear or the convex probes without shaving the hair could be a promising tool for the on-field diagnosis of pneumonia, although further research on larger sample sizes are necessary to validate these findings.
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Geopolymers are amorphous aluminosilicate inorganic polymers synthesized by alkaline activation characterized by a lower carbon footprint, greater durability, and excellent mechanical properties compared to traditional concrete, making them promising building materials for sustainable construction. To develop sustainable lightweight geopolymer-based building materials useful as fire resistant thermal insulation materials, we added 5 and 10 wt% of discarded cork dust, a readily available industrial by-product, to metakaolin before and after the alkaline activation with sodium hydroxide 8 M and sodium silicate solutions. We followed the chemical, microstructural, antibacterial, and physical properties of the resulting composites for up to 90 days in order to monitor their long-term durability. The presence of cork does not interfere with the geopolymerization process and in fact reduces the density of the composites to values around 2.5 g/cm3, especially when added after alkaline activation. The composites resulted in chemically stable matrices (less than 10 ppm of cations release) and filler (no hazardous compounds released) with a bacterial viability of around 80%. This study provides valuable insights into the tailoring of discarded cork-based composites obtained by geopolymerization with a porosity between 32 and 48% and a mechanical resistance to compression from 15 to 5 MPa, respectively, suggesting their potential as durable interior panels with low environmental impact and desirable performance.
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Materiais de Construção , Quercus/química , Polímeros/químicaRESUMO
Cyclodextrins (CDs) are cyclic oligosaccharides able to form noncovalent water-soluble complexes useful in many different applications for the solubilization, delivery, and greater bioavailability of hydrophobic drugs. The complexation of 5-fluorouracil (5-FU) with natural or synthetic cyclodextrins permits the solubilization of this poorly soluble anticancer drug. In this theoretical work, the complexes between ß-CD and 5-FU are investigated using molecular mechanics (MM) and molecular dynamics (MD) simulations in water. The inclusion complexes are formed thanks to the favorable intermolecular interactions between ß-CD and 5-FU. Both 1:1 and 1:2 ß-CD/5-FU stoichiometries are investigated, providing insight into their interaction geometries and stability over time in water. In the 1:2 ß-CD/5-FU complexes, the intermolecular interactions affect the drug's mobility, suggesting a two-step release mechanism: a fast release for the more exposed and hydrated drug molecule, with greater freedom of movement near the ß-CD rims, and a slow one for the less-hydrated and well-encapsulated and confined drug. MD simulations study the intermolecular interactions between drugs and specific carriers at the atomistic level, suggesting a possible release mechanism and highlighting the role of the impact of the drug concentration on the kinetics process in water. A comparison with experimental data in the literature provides further insights.
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Fluoruracila , Interações Hidrofóbicas e Hidrofílicas , Simulação de Dinâmica Molecular , Água , beta-Ciclodextrinas , Fluoruracila/química , beta-Ciclodextrinas/química , Água/química , SolubilidadeRESUMO
SOD1 gene is associated with progressive motor neuron degeneration in the familiar forms of amyotrophic lateral sclerosis. Although studies on mutant human SOD1 transgenic rodent models have provided important insights into disease pathogenesis, they have not led to the discovery of early biomarkers or effective therapies in human disease. The recent generation of a transgenic swine model expressing the human pathological hSOD1G93A gene, which recapitulates the course of human disease, represents an interesting tool for the identification of early disease mechanisms and diagnostic biomarkers. Here, we analyze the activation state of CNS cells in transgenic pigs during the disease course and investigate whether changes in neuronal and glial cell activation state can be reflected by the amount of extracellular vesicles they release in biological fluids. To assess the activation state of neural cells, we performed a biochemical characterization of neurons and glial cells in the spinal cords of hSOD1G93A pigs during the disease course. Quantification of EVs of CNS cell origin was performed in cerebrospinal fluid and plasma of transgenic pigs at different disease stages by Western blot and peptide microarray analyses. We report an early activation of oligodendrocytes in hSOD1G93A transgenic tissue followed by astrocyte and microglia activation, especially in animals with motor symptoms. At late asymptomatic stage, EV production from astrocytes and microglia is increased in the cerebrospinal fluid, but not in the plasma, of transgenic pigs reflecting donor cell activation in the spinal cord. Estimation of EV production by biochemical analyses is corroborated by direct quantification of neuron- and microglia-derived EVs in the cerebrospinal fluid by a Membrane Sensing Peptide enabled on-chip analysis that provides fast results and low sample consumption. Collectively, our data indicate that alteration in astrocytic EV production precedes the onset of disease symptoms in the hSODG93A swine model, mirroring donor cell activation in the spinal cord, and suggest that EV measurements from the cells first activated in the ALS pig model, i.e. OPCs, may further improve early disease detection.
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Esclerose Lateral Amiotrófica , Vesículas Extracelulares , Camundongos , Animais , Humanos , Suínos , Superóxido Dismutase-1/genética , Neurônios Motores/metabolismo , Superóxido Dismutase/genética , Camundongos Transgênicos , Esclerose Lateral Amiotrófica/patologia , Medula Espinal/patologia , Neuroglia/patologia , Biomarcadores/metabolismo , Peptídeos/metabolismo , Modelos Animais de DoençasRESUMO
Introduction: Constant rate infusion (CRI) of benzodiazepines or propofol (PPF) is a therapeutic option for cluster seizures (CS) and status epilepticus (SE) in canine patients non-responding to first-line benzodiazepines or non-anesthetics. However, specific indications for optimal duration of CRI are lacking. The aim of this study was to determine the effect of duration of anesthetic CRI on outcome and length of hospital stay in dogs with refractory seizure activity of different etiology. Study design: Open-label non-randomized clinical trial. Materials and methods: Seventy-three client-owned dogs were enrolled. Two groups [experimental (EXP) vs. control (CTRL)] were compared. The EXP group received diazepam (DZP) or PPF CRI for 12 h (±1 h) and the CTRL group received DZP or PPF CRI for 24 h (±1 h) in addition to a standardized emergency treatment protocol identical for both study groups. The historical control group was made up of a population of dogs already reported in a previously published paper by the same authors. Favorable outcome was defined as seizure cessation after CRI, no seizure recurrence, and clinical recovery. Poor outcome was defined as seizure recurrence, death in hospital or no return to acceptable clinical baseline. Univariate statistical analysis was performed. Results: The study sample was 73 dogs: 45 (62%) received DZP CRI and 28 (38%) received PPF CRI. The EXP group was 39 dogs (25 DZP CRI and 14 PPF CRI) and the CTRL group 34 dogs (20 DZP CRI and 14 PPF CRI). We found no statistically significant difference in outcomes between the groups. The median length of stay was 56 h (IQR, 40-78) for the ALL EXP group and 58.5 h (IQR, 48-74.5) for the ALL CTRL group (p = 0.8). Conclusion: Even though a shorter DZP or PPF CRI duration was not associated with a worse outcome, the study failed to identify a clear superiority of shorter CRI duration on outcome or length of hospital stay in dogs with refractory seizure activity of different etiology.
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Organic-inorganic hybrid materials were synthesized by a sol-gel route, using silicon alkoxide together with low molecular weight polycaprolactone and caffetannic acid. The synthesized hybrids were characterized by scanning Fourier-transform infrared (FTIR) spectroscopy, and their surface morphology was acquired by scanning electron microscopy (SEM) analysis. The hybrids were investigated for their antiradical capacity using the DPPH and ABTS tests, while the Kirby-Bauer test was used to evaluate their effects on the growth of Escherichia coli and Enterococcus faecalis. Furthermore, a biologically active hydroxyapatite layer has been observed to form on the surface of intelligently synthesized materials. The MTT direct test showed that the hybrid materials are biocompatible with NIH-3T3 fibroblast cells, while they were cytotoxic towards colon, prostate, and brain tumor cell lines. These results shed new light on the suitability of the synthesized hybrids in the medical field, thus affording knowledge on the features of the bioactive silica-polycaprolactone-chlorogenic acid hybrids.
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Ácido Clorogênico , Dióxido de Silício , Dióxido de Silício/química , Ácido Clorogênico/química , Durapatita/química , Espectroscopia de Infravermelho com Transformada de Fourier , Microscopia Eletrônica de Varredura , Antibacterianos/farmacologia , Materiais Biocompatíveis/químicaRESUMO
BACKGROUND: Central nervous system (CNS) infections in cattle are a major cause of economic loss and mortality. Machine learning (ML) techniques are gaining widespread application in solving predictive tasks in both human and veterinary medicine. OBJECTIVES: Our primary aim was to develop and compare ML models that could predict the likelihood of a CNS disorder of infectious or inflammatory origin in neurologically-impaired cattle. Our secondary aim was to create a user-friendly web application based on the ML model for the diagnosis of infection and inflammation of the CNS. ANIMALS: Ninety-eight cattle with CNS infection and 86 with CNS disorders of other origin. METHODS: Retrospective observational study. Six different ML methods (logistic regression [LR]; support vector machine [SVM]; random forest [RF]; multilayer perceptron [MLP]; K-nearest neighbors [KNN]; gradient boosting [GB]) were compared for their ability to predict whether an infectious or inflammatory disease was present based on demographics, neurological examination findings, and cerebrospinal fluid (CSF) analysis. RESULTS: All 6 methods had high prediction accuracy (≥80%). The accuracy of the LR model was significantly higher (0.843 ± 0.005; receiver operating characteristic [ROC] curve 0.907 ± 0.005 ) than the other models and was selected for implementation in a web application. CONCLUSION AND CLINICAL IMPORTANCE: Our findings support the use of ML algorithms as promising tools for veterinarians to improve diagnosis. The open-access web application may aid clinicians in achieving correct diagnosis of infectious and inflammatory neurological disorders in livestock, with the added benefit of promoting appropriate use of antimicrobials.
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Doenças dos Bovinos , Doenças do Sistema Nervoso Central , Animais , Bovinos , Algoritmos , Doenças dos Bovinos/diagnóstico , Sistema Nervoso Central , Doenças do Sistema Nervoso Central/veterinária , Aprendizado de Máquina , Curva ROC , SoftwareRESUMO
BACKGROUND: The aim of study was to assess the safety and effectiveness of 3 different commercial iliac branch devices (IBDs): the Zenith Branch Iliac Endovascular Graft; the Gore Excluder Iliac Branch System and the E-liac Stent Graft System for the treatment of aorto-iliac or iliac aneurysms. METHODS: From January 2017 to February 2020, a retrospective reviewed was conducted on a total of 96 patients. Primary endpoint was IBD instability rate at 24 months. Secondary endpoints included onset of any endoleaks, buttock claudication, IBD-related reintervention and all-death rates, postoperative acute kidney, and changes in maximum diameter from baseline of the aortic aneurysmal sac. RESULTS: At 24 months, the branch instability rate was similar among the 3 IBDs employed [Jotec 1/24 (4.1%), Gore 1/12 (8.3%), Cook 6/47 (12.7%), P-value = 0.502]. As well, no statistical difference in terms of branch occlusion and branch-related endoleaks was observed. The Jotec group showed a significant decrease in maximum diameter from the baseline of the aortic aneurysmal sac when compared to the Gore group alone. No other differences were found relevant to the onset of any endoleaks, reinterventions, and all-death rates. At 24 months, the Kaplan-Meier estimate of survival freedom from any branch instability was 95.8%, 91.6%, and 86.8% for Jotec, Gore and Cook groups, respectively. CONCLUSIONS: The use of IBDs represents a safe method for preserving patency of the IIA during treatment of aorto-iliac or iliac aneurysms providing a low rate of IBD instability.
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Implante de Prótese Vascular , Procedimentos Endovasculares , Aneurisma Ilíaco , Humanos , Prótese Vascular , Aneurisma Ilíaco/diagnóstico por imagem , Aneurisma Ilíaco/cirurgia , Stents , Endoleak/diagnóstico por imagem , Endoleak/etiologia , Endoleak/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Fatores de Tempo , Desenho de PróteseRESUMO
Ocular ultrasonography is seldom performed in cattle. Here, we compared three ultrasound probes (linear, convex, transrectal gynecological) for the measurement of eight eye biometry parameters on vertical and horizontal scans. The sample population was 20 healthy calves (n = 10 Holstein, n = 10 Piedmontese breed). Intragroup (same probe for vertical vs. horizontal scanning) and intergroup (different probes measuring the same biometric parameter) comparisons were performed using Student's t-test and the Mann-Whitney U test. Statistical significance was set at p ≤ 0.05. Intragroup comparison revealed few significant differences. Ultrasound examination with the convex transducer detected more differences than either of the two other probes on vertical (linear six out of eight; transrectal gynecological four out of eight) and horizontal (linear six out of eight; transrectal gynecological six out of eight) scans. Similar results were obtained for both breeds. More non-valuable parameters on the horizontal (77 out of 320, 24%) and the vertical (85 out of 320, 26%) (p ≤ 0.001) scans were obtained with the convex transducer. Both linear transducers were found comparable for ocular ultrasonography in field conditions. However, given its widespread application in the field, the transrectal gynecological transducer may offer veterinarians the added advantage of familiarity and ease-of-use without any additional costs.
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Few studies have explored the immobilization of organic macromolecules within the geopolymer matrix, and some have found their chemical instability in the highly alkaline geopolymerization media. The present work reports on the feasibility of encapsulating the potentially toxic acridine orange (AO) dye in a metakaolin based geopolymer while maintaining its structural integrity. The proper structural, chemical, and mechanical stabilities of the final products were ascertained using Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric (TGA/DTG), and mechanical analyses, whereas the dye integrity and its stability inside the geopolymer were investigated by the UV-Vis analysis. In addition, the antimicrobial activity was investigated. The FT-IR and XRD analyses confirmed the geopolymerization occurrence, whereas the TGA/DTG and mechanical (compressive and flexural) strength revealed that the addition of 0.31% (AO mg/ sodium silicate L) of AO to the fresh paste did not affect the thermal stability and the mechanical properties (above 6 MPa in flexural strength and above 20 MPa for compressive strength) of the hardened product. UV-Vis spectroscopy revealed that the dye did not undergo chemical degradation nor was it released from the geopolymer matrix. The results reported herein provide a useful approach for the safe removal of toxic macromolecules by means of encapsulation within the geopolymer matrix.
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Amyotrophic lateral sclerosis (ALS) is a complex disease characterized by the interplay of genetic and environmental factors for which, despite decades of intense research, diagnosis remains rather delayed, and most therapeutic options fail. Therefore, unravelling other potential pathogenetic mechanisms and searching for reliable markers are high priorities. In the present study, we employ the SOMAscan assay, an aptamer-based proteomic technology, to determine the circulating proteomic profile of ALS patients. The expression levels of ~1300 proteins were assessed in plasma, and 42 proteins with statistically significant differential expression between ALS patients and healthy controls were identified. Among these, four were upregulated proteins, Thymus- and activation-regulated chemokine, metalloproteinase inhibitor 3 and nidogen 1 and 2 were selected and validated by enzyme-linked immunosorbent assays in an overlapping cohort of patients. Following statistical analyses, different expression patterns of these proteins were observed in the familial and sporadic ALS patients. The proteins identified in this study might provide insight into ALS pathogenesis and represent potential candidates to develop novel targeted therapies.
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Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/metabolismo , Proteômica , Proteínas SanguíneasRESUMO
OBJECTIVE: Despite growing interests in patient-reported outcomes, youth and families are rarely involved in designing quality improvement measures. Few quality indicators exist for the care of children with injuries in the Emergency Department (ED) and extremity fractures are among the most common injuries in children. This study's aim was to identify both parents' and youth's perspectives about ED care in the context of a suspected long-bone fracture. METHODS: Youth (10-18 years old) and their parents were surveyed prospectively during their ED visit. Participants were asked: 1) to identify their main concerns, 2) to identify quality measures that were most important to them, and 3) to evaluate the ED care they received. Descriptive analyses present participants' responses. Continuous data was analyzed using a Student t-test and categorical data using a Chi-square test. RESULTS: Over 15 months, 350 families met eligibility criteria and were approached to participate, of which 300 participants consented and 249 surveys were completed (71% response rate): 148 parents and 101 youth (median age: 12) completed their respective surveys. Participants placed a high importance on several themes: pain management, short length of stay, and quality interactions with ED clinicians. Youth as a group prioritized their overall wellbeing and the ED environment (e.g., waiting room comfort, signage), while parents focused on accurate diagnoses and treatments. The following items were less prioritized: that radiology be close to the ED, to see the radiograph, to have access to a wheelchair, to know the identities of clinicians on the team, and to have access to entertainment. Parents and youth within the same family often did not share the same priorities. Ninety-two percent of parents reported their child's pain was treated, while 81% and 63% of youth reported their pain was treated sufficiently and quickly, respectively. CONCLUSIONS: Parents and youth can identify their priorities for ED care and should be engaged in efforts to improve and report on the quality of care in the ED. Youths' and parents' perspectives are complimentary and may not align, even within families. The priorities identified in this study can help inform quality improvement initiatives and personalized patient care.
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Serviços Médicos de Emergência , Fraturas Ósseas , Criança , Adolescente , Humanos , Pais , Serviço Hospitalar de Emergência , Inquéritos e Questionários , Fraturas Ósseas/terapiaRESUMO
Bacterial infection of the central nervous system (CNS) in cattle requires prompt and adequate antimicrobial treatment. The current gold standard for antemortem etiological diagnosis is cerebrospinal fluid (CSF) culture, which often yields false negative results. CSF has long been considered a sterile district in healthy patients, but this notion has been recently challenged. For this pilot study, we used 16S rRNA gene sequencing to investigate the microbial composition of CSF of cattle presenting with CNS disorders and to compare it between subjects with CNS infections and with CNS disorders of other nature. The study sample was 10 animals: 4 presenting with CNS infectious-inflammatory diseases and 6 with other CNS disorders, based on definitive diagnosis. Since the initial round of a standard 16S rRNA PCR did not yield sufficient genetic material for sequencing in any of the samples, the protocol was modified to increase its sensitivity. Bacterial genetic material was identified in 6 animals and 2 groups were formed: an infectious inflammatory (n = 3) and a noninfectious inflammatory group (n = 3). The most frequently expressed bacterial families were Pseudomonadaceae (44.61%), Moraxellaceae (19.54%), Mycobacteriaceae (11.80%); the genera were Pseudomonas (45.42%), Acinetobacter (19.91%), Mycobacterium (12.01%). There were no detectable differences in the CSF microbial composition of the samples from the two groups. Sequencing of bacterial DNA present in the CSF was possible only after increasing PCR sensitivity. The results of 16S rRNA sequencing showed the presence of a microbial community in the CSF in cattle with neurological disorders. Further studies, in which CSF samples from healthy animals and samples from the environment are included as controls, are needed.
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Doenças dos Bovinos , Microbiota , Doenças do Sistema Nervoso , Bovinos , Animais , RNA Ribossômico 16S/genética , Projetos Piloto , Estudos de Viabilidade , Bactérias/genética , Doenças do Sistema Nervoso/veterinária , Doenças dos Bovinos/diagnósticoRESUMO
Introduction: Cluster seizures (CS) and status epilepticus (SE) in dogs are severe neurological emergencies that require immediate treatment. Practical guidelines call for constant rate infusion (CRI) of benzodiazepines or propofol (PPF) in patients with seizures not responding to first-line treatment, but to date only few studies have investigated the use of CRI in dogs with epilepsy. Study design: Retrospective clinical study. Methods: Dogs that received CRI of diazepam (DZP) or PPF for antiepileptic treatment during hospitalization at the Veterinary Teaching Hospital of the University of Turin for CS or SE between September 2016 and December 2019 were eligible for inclusion. Favorable outcome was defined as cessation of clinically visible seizure activity within few minutes from the initiation of the CRI, no seizure recurrence within 24 h after discontinuation of CRI through to hospital discharge, and clinical recovery. Poor outcome was defined as recurrence of seizure activity despite treatment or death in hospital because of recurrent seizures, catastrophic consequences of prolonged seizures or no return to an acceptable neurological and clinical baseline, despite apparent control of seizure activity. Comparisons between the number of patients with favorable outcome and those with poor outcome in relation to type of CRI, seizure etiology, reason for presentation (CS or SE), sex, previous AED therapy and dose of PPF CRI were carried out. Results: A total of 37 dogs, with 50 instances of hospitalization and CRI administered for CS or SE were included in the study. CRI of diazepam (DZP) or PPF was administered in 29/50 (58%) and in 21/50 (42%) instances of hospitalization, respectively. Idiopathic epilepsy was diagnosed in 21/37 (57%), (13/21 tier I and 8/21 tier II); structural epilepsy was diagnosed in 6/37 (16%) of which 4/6 confirmed and 2/6 suspected. A metabolic or toxic cause of seizure activity was recorded in 7/37 (19%). A total of 38/50 (76%) hospitalizations were noted for CS and 12/50 (24%) for SE. In 30/50 (60%) instances of hospitalization, the patient responded well to CRI with cessation of seizure activity, no recurrence in the 24 h after discontinuation of CRI through to hospital discharge, whereas a poor outcome was recorded for 20/50 (40%) cases (DZP CRI in 12/50 and PPF CRI in 8/50). Comparison between the number of patients with favorable outcome and those with poor outcome in relation to type of CRI, seizure etiology, reason for presentation (CS or SE), sex and previous AED therapy was carried out but no statistically significant differences were found. Conclusions: The present study is the first to document administration of CRI of DZP or PPF in a large sample of dogs with epilepsy. The medications appeared to be tolerated without major side effects and helped control seizure activity in most patients regardless of seizure etiology. Further studies are needed to evaluate the effects of CRI duration on outcome and complications.
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Over the years, many materials have been used to restore buildings, paintings, ceramics, and mosaic pieces exhibiting different types of dyes and colour hues. Recently, geopolymers have been used for restoration purposes owing to their high chemical and mechanical resistance. In this work, white metakaolin was used to obtain white geopolymers, cured at 25 and 40 °C, as bulk materials to be coloured with synthetic organic dyes, i.e., bromothymol blue, cresol red, phenolphthalein, and methyl orange. These dyes were added during the fresh paste preparation to obtain dyed geopolymeric solids. Ionic conductivity and pH measurement confirmed the chemical stability of the consolidated materials, while FT-IR analyses were used to follow the geopolymerisation occurrences at different ageing times (from 7 to 56 days). Finally, the colour hues and properties were assessed in the CIELAB colour space before and after immersion in water.
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Recycling corundum abrasive powder in metakaolin-based geopolymer formulations is proposed to reduce the amount of waste to be treated or disposed of in landfills, allowing to decrease ecological damage as well as to reduce transport costs for removal. The addition of waste corundum, as an important source of Al2O3, has proved to increase the slight ionic conductivity of the leachate solution obtained after immersion in water of samples at 28 d of curing at room temperature. With the same curing conditions, the geopolymerization process has not been disturbed as evidenced by the FT-IR peak shift and XRD patterns. It was recorded a decrease in resistance to compression of the consolidated geopolymers of about 5% with 10 wt% addition and of about 77% with the addition of 20 wt% of waste corundum. In any case, the waste abrasive powder does not release heavy metals when added to a geopolymeric formulation based on MK, NaOH, and Na-silicate, and does not show relevant antibacterial properties, indicating the formation of a stable and safe final product with a ceramic-like appearance.
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This paper aims to synthesize, via the sol-gel method, a biomaterial usable in the medical field. Here, the silica-PEG-quercetin system was evaluated in relation to the different concentrations of PEG (0, 6, 12, 24, 50 wt%) and quercetin (0, 5, 10, 15 wt%), respectively. In addition, Fourier Transform-Infrared spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), and Kirby-Bauer analyses were performed. FT-IR was used to evaluate the hybrid formation and the influence of both PEG and Quercetin in the hybrid synthesized materials, SEM was used to evaluate the morphological properties, while the Kirby-Bauer test was used to understand the ability of the materials to inhibit the growth of the assayed bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus).
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Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Polietilenoglicóis/química , Quercetina/química , Dióxido de Silício/química , Bactérias/classificação , Materiais Biocompatíveis/química , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
OBJECTIVE: The spread of bovine spongiform encephalopathy (BSE) agent to small ruminants is still a major issue in the surveillance of transmissible spongiform encephalopathies (TSEs). L-type bovine spongiform encephalopathy (L-BSE) is an atypical form of BSE with an unknown zoonotic potential that is transmissible to cattle and small ruminants. Our current knowledge of bovine atypical prion strains in sheep and goat relies only on experimental transmission studies by intracranial inoculation. To assess oral susceptibility of goats to L-BSE, we orally inoculated five goats with cattle L-BSE brain homogenates and investigated pathogenic prion protein (PrPsc) distribution by an ultrasensitive in vitro conversion assay known as Real-Time Quaking Induced Conversion (RT-QuIC). RESULTS: Despite a prolonged observation period of 80 months, all these animals and the uninfected controls did not develop clinical signs referable to TSEs and tested negative by standard diagnostics. Otherwise, RT-QuIC analysis showed seeding activity in five out of five examined brain samples. PrPsc accumulation was also detected in spinal cord and lymphoreticular system. These results indicate that caprine species are susceptible to L-BSE by oral transmission and that ultrasensitive prion tests deserve consideration to improve the potential of current surveillance systems against otherwise undetectable forms of animal prion infections.
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Encefalopatia Espongiforme Bovina , Doenças Priônicas , Príons , Animais , Encéfalo/metabolismo , Bovinos , Encefalopatia Espongiforme Bovina/diagnóstico , Cabras , Doenças Priônicas/diagnóstico , Doenças Priônicas/veterinária , Proteínas Priônicas/metabolismo , OvinosRESUMO
The up-to-date literature suggests that the compost-bedded pack barn housing system is capable of remarkably improving productive and reproductive performance, as well as health status and welfare, in dairy cattle. However, there is currently limited knowledge available on the endocrine and biochemical changes in animals housed in such alternative systems. Therefore, this study aimed to measure blood cortisol (COR) and beta-endorphins (BE) in 22 two-year-old primiparae Fleckvieh cows, who were randomly allotted to the following two different housing systems: CB (n = 11) and FB (n = 11). Blood samples were collected at the beginning of the experiment (T0) and every two months thereafter (T1, T2, and T3). The COR and BE were measured through an immunoenzymatic kit. With the only exception being T0, no differences were observed over time between the two groups, neither for COR nor for BE. However, the blood cortisol levels of the CB cows decreased over time, while a T1 peak was identified in the FB group. On the contrary, both the housing systems displayed numerically higher BE at T3 than at the other experimental times. Therefore, the overall data suggest that the compost-bedded pack barn did not significantly affect the studied parameters. Accordingly, cow welfare should be assessed using a wider panel of animal-based indicators.