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Two phase-III clinical trials with anti-amyloid peptide antibodies have met their primary goal, i.e. slowing of Alzheimer's disease (AD) progression. However, antibody therapy may not be the optimal therapeutic modality for AD prevention, as we will discuss in the context of the earlier small molecules described as "γ-secretase modulators" (GSM). We review here the structure, function, and pathobiology of γ-secretases, with a focus on how mutations in presenilin genes result in early-onset AD. Significant progress has been made in generating compounds that act in a manner opposite to pathogenic presenilin mutations: they stabilize the proteinase-substrate complex, thereby increasing the processivity of substrate cleavage and altering the size spectrum of Aß peptides produced. We propose the term "γ-secretase allosteric stabilizers" (GSAS) to distinguish these compounds from the rather heterogenous class of GSM. The GSAS represent, in theory, a precision medicine approach to the prevention of amyloid deposition, as they specifically target a discrete aspect in a complex cell biological signalling mechanism that initiates the pathological processes leading to Alzheimer's disease.
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Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/prevenção & controle , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/química , Peptídeos beta-Amiloides/genética , Medicina de Precisão , Presenilinas/uso terapêutico , Presenilina-1/genética , Precursor de Proteína beta-Amiloide/genéticaRESUMO
Protein-protein interaction (PPI) modulation is a promising approach in drug discovery with the potential to expand the 'druggable' proteome and develop new therapeutic strategies. While there have been significant advancements in methodologies for developing PPI inhibitors, there is a relative scarcity of literature describing the 'bottom-up' development of PPI stabilizers (Molecular Glues). The hub protein 14-3-3 and its interactome provide an excellent platform for exploring conceptual approaches to PPI modulation, including evolution of chemical matter for Molecular Glues. In this study, we employed a fragment extension strategy to discover stabilizers for the complex of 14-3-3 protein and an Estrogen Receptor alpha-derived peptide (ERα). A focused library of analogues derived from an amidine-substituted thiophene fragment enhanced the affinity of the 14-3-3/ERα complex up to 6.2-fold. Structure-activity relationship (SAR) analysis underscored the importance of the newly added, aromatic side chain with a certain degree of rigidity. X-ray structural analysis revealed a unique intermolecular π-π stacking binding mode of the most active analogues, resulting in the simultaneous binding of two molecules to the PPI binding pocket. Notably, analogue 11 displayed selective stabilization of the 14-3-3/ERα complex.
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Proteínas 14-3-3 , Receptor alfa de Estrogênio , Proteínas 14-3-3/química , Ligação Proteica , Descoberta de Drogas/métodos , Relação Estrutura-AtividadeRESUMO
Drug design targeting protein-protein interactions (PPIs) associated with the development of diseases has been one of the most important therapeutic strategies. Besides interrupting the PPIs with PPI inhibitors/blockers, increasing evidence shows that stabilizing the interaction between two interacting proteins may also benefit the therapy, such as the development of various types of molecular glues/stabilizers that mostly work by stabilizing the two interacting proteins to regulate the downstream biological effects. However, characterizing the stabilization effect of a stabilizer is usually hard or too complicated for traditional experiments since it involves ternary interactions [protein-protein-stabilizer (PPS) interaction]. Thus, developing reliable computational strategies will facilitate the discovery/design of molecular glues or PPI stabilizers. Here, by fully analyzing the energetic features of the binary interactions in the PPS ternary complex, we systematically investigated the performance of molecular mechanics Poisson-Boltzmann surface area (MM/PBSA) and molecular mechanics generalized Born surface area (MM/GBSA) methods on characterizing the stabilization effects of stabilizers in 14-3-3 systems. The results show that both MM/PBSA and MM/GBSA are powerful tools in distinguishing the stabilizers from the decoys (with area under the curves of 0.90-0.93 for all tested cases) and are reasonable for ranking protein-peptide interactions in the presence or absence of stabilizers as well (with the average Pearson correlation coefficient of ~0.6 at a relatively high dielectric constant for both methods). Moreover, to give a detailed picture of the stabilization effects, the stabilization mechanism is also analyzed from the structural and energetic points of view for individual systems containing strong or weak stabilizers. This study demonstrates a potential strategy to accelerate the discovery of PPI stabilizers.
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Simulação de Dinâmica Molecular , Proteínas , Desenho de Fármacos , Entropia , Peptídeos , Ligação Proteica , Proteínas/químicaRESUMO
INTRODUCTION: Untreated bipolar disorder in pregnancy is associated with adverse maternal and neonatal outcomes. Despite advances in clinical management, there is concern among obstetric providers and patients about the safety of pharmacological agents for the treatment of bipolar disorder in pregnancy. Recent studies have shown atypical antipsychotics and lamotrigine to have a favorable safety profile; however, little information is published on lurasidone. OBJECTIVES: The objective of this retrospective chart review was to evaluate pregnancy and neonatal outcomes in obstetric patients with bipolar disorder who are untreated, compared to those treated with lurasidone, other atypical antipsychotics, and lamotrigine at a tertiary teaching institution. METHODS: This retrospective cohort study included neonates whose mothers had a diagnosis of bipolar disorder and were referred to the Maternal & Fetal Care Clinic with two documented visits after January 1, 2014, with delivery by October 31, 2017, within an SSM health-system hospital. RESULTS: In this study, women with untreated bipolar disorder (not on any mood stabilizer) in pregnancy had significantly higher rates of premature delivery and low birth weight compared to women on mood stabilizers of lamotrigine, lurasidone, and other atypical antipsychotics. No difference was observed for pregnancy or neonatal outcomes between patients taking any of the mood stabilizers. CONCLUSIONS: This study suggests that the use of lurasidone, other atypical antipsychotics, and lamotrigine have better neonatal outcomes than untreated bipolar disorder in pregnancy.
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OBJECTIVES: To understand treatment practices for bipolar disorders (BD), this study leveraged the Global Bipolar Cohort collaborative network to investigate pharmacotherapeutic treatment patterns in multiple cohorts of well-characterized individuals with BD in North America, Europe, and Australia. METHODS: Data on pharmacotherapy, demographics, diagnostic subtypes, and comorbidities were provided from each participating cohort. Individual site and regional pooled proportional meta-analyses with generalized linear mixed methods were conducted to identify prescription patterns. RESULTS: This study included 10,351 individuals from North America (n = 3985), Europe (n = 3822), and Australia (n = 2544). Overall, participants were predominantly female (60%) with BD-I (60%; vs. BD-II = 33%). Cross-sectionally, mood-stabilizing anticonvulsants (44%), second-generation antipsychotics (42%), and antidepressants (38%) were the most prescribed medications. Lithium was prescribed in 29% of patients, primarily in the Australian (31%) and European (36%) cohorts. First-generation antipsychotics were prescribed in 24% of the European versus 1% in the North American cohort. Antidepressant prescription rates were higher in BD-II (47%) compared to BD-I (35%). Major limitations were significant differences among cohorts based on inclusion/exclusion criteria, data source, and time/year of enrollment into cohort. CONCLUSIONS: Mood-stabilizing anticonvulsants, second-generation antipsychotics, and antidepressants were the most prescribed medications suggesting prescription patterns that are not necessarily guideline concordant. Significant differences exist in the prescription practices across different geographic regions, especially the underutilization of lithium in the North American cohorts and the higher utilization of first-generation antipsychotics in the European cohorts. There is a need to conduct future longitudinal studies to further explore these differences and their impact on outcomes, and to inform and implement evidence-based guidelines to help improve treatment practices in BD.
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Antipsicóticos , Transtorno Bipolar , Humanos , Feminino , Masculino , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/diagnóstico , Lítio/uso terapêutico , Anticonvulsivantes/uso terapêutico , Austrália/epidemiologia , Antipsicóticos/uso terapêutico , Antidepressivos/uso terapêuticoRESUMO
OBJECTIVE: Few studies have addressed medication adherence in adolescents and young adults (AYAs) with bipolar disorder (BD). This 6-month prospective randomized-controlled trial (RCT) tested customized adherence enhancement for adolescents and young adults (CAE-AYA), a behavioral intervention for AYAs versus enhanced treatment as usual (ETAU). METHODS: Inclusion criteria were AYAs age 13-21 with BD type I or II with suboptimal adherence defined as missing ≥20% of medications. Assessments were conducted at Screening, Baseline, and weeks 8, 12 and 24. Primary outcome was past 7 day self-reported Tablets Routine Questionnaire (TRQ) validated by electronic pillbox monitoring (SimpleMed). Symptom measures included the Hamilton Depression Rating Scale (HAM-D) and Young Mania Rating Scale (YMRS). RESULTS: The mean sample age (N = 36) was 19.1 years (SD = 2.0); 66.7% (N = 24) female, BD Type I (81%). The mean missed medication on TRQ for the total sample was 35.4% (SD = 28.8) at screening and 30.4% (SD = 30.5) at baseline. Both CAE-AYA and ETAU improved on TRQ from screening to baseline. Baseline mean missed medication using SimpleMed was 51.6% (SD = 38.5). Baseline HAM-D and YMRS means were 7.1 (SD = 4.7) and 6.0 (SD = 7.3), respectively. Attrition rate at week 24 was 36%. Baseline to 24-week change on TRQ, adjusting for age, gender, educational level, living situation, family history, race, and ethnicity, showed improvement favoring CAE-AYA versus ETAU of 15%. SimpleMed interpretation was limited due to substantial missing data. There was a significant reduction in depression favoring CAE-AYA. CONCLUSIONS: CAE-AYA may improve adherence in AYAs with BD, although conclusions need to be made cautiously given study limitations. CLINICAL TRIALS REGISTRATION: ClinicalTrials.gov identifier: NCT04348604.
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BACKGROUND: Weight gain is a common side effect in psychopharmacology; however, targeted therapeutic interventions and prevention strategies are currently absent in day-to-day clinical practice. To promote the development of such strategies, the identification of factors indicative of patients at risk is essential. METHODS: In this study, we developed a transdiagnostic model using and comparing decision tree classifiers, logistic regression, XGboost, and a support vector machine to predict weight gain of ≥5% of body weight during the first 4 weeks of treatment with psychotropic drugs associated with weight gain in 103 psychiatric inpatients. We included established variables from the literature as well as an extended set with additional clinical variables and questionnaires. RESULTS: Baseline BMI, premorbid BMI, and age are known risk factors and were confirmed by our models. Additionally, waist circumference has emerged as a new and significant risk factor. Eating behavior next to blood glucose were found as additional potential predictor that may underlie therapeutic interventions and could be used for preventive strategies in a cohort at risk for psychotropics induced weight gain (PIWG). CONCLUSION: Our models validate existing findings and further uncover previously unknown modifiable factors, such as eating behavior and blood glucose, which can be used as targets for preventive strategies. These findings underscore the imperative for continued research in this domain to establish effective preventive measures for individuals undergoing psychotropic drug treatments.
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OBJECTIVES: To evaluate the impact of guide stabilizers and their application sequences on implant placement accuracy of guided implant surgery in multiple teeth loss at free end. MATERIALS AND METHODS: In this study, 96 implants were placed in the regions of #34, #36, and #37 of 32 identical mandibular models. The influence of using guide stabilizers or not (group A and group B) and various guide stabilizers application sequences (group B: #34 â #36 â #37; group C: #36 â #34 â #37; group D: #37 â #34 â #36) on implant placement trueness and precision was investigated. Data were analyzed using T-tests and one-way ANOVA. RESULTS: Group B showed significant benefits in enhancing implant placement precision. Compared to group A, it resulted in reducing 3D-deviation at crest and 2D deviation in vestibular-oral direction at both crest and apex. Furthermore, group D demonstrated greater improvement in global implant placement precision by reducing 2D deviation in mesial-distal direction at both crest and apex. Among the three different stabilizer application sequences, group D exhibited the highest level of implant placement precision. CONCLUSIONS: In cases of missing teeth at distal free end, the use of guide stabilizers and their application sequences does not have a significant impact on implant placement trueness. However, they do improve implant placement precision compared to methods that do not utilize guide stabilizers. Specifically, applying a guide stabilizer first at the furthest implant site to change teeth loss classification from free end to edentulous space with posterior support is the most reliable sequence.
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Implantes Dentários , Boca Edêntula , Cirurgia Assistida por Computador , Perda de Dente , Humanos , Implantação Dentária Endóssea/métodos , Desenho Assistido por Computador , Imageamento Tridimensional , Tomografia Computadorizada de Feixe CônicoRESUMO
PURPOSE: The current standard method for pectus excavatum (PE) repair is the Nuss procedure. One major postoperative complication is the displacement of the implanted metal bar, which is used to remodel the chest wall. Blocking the possible ways that the bar can be displaced with the use of stabilizers and peri/intracostal sutures has reduced the incidence of bar displacement. Despite the modifications, bar dislocation is often reported. We adopted the medial position stabilizer placement method and imposed no postoperative restrictions. In this study, we analyzed the bar dislocation rate with this modification and concurrent postoperative full activity. METHODS: Nuss procedure modification where stabilizers are placed bilaterally in the medial location was done on patients irrespective of age and Haller index greater than 3.25. A single bar was used for all patients. Cryoanalgesia was performed on every patient. No postoperative restrictions were imposed on the patients. Full immediate activities, including sports, were allowed. RESULTS: 114 patients (103 male, 11 female) were analyzed from 2016 to 2023. The median age was 15 years old. There was zero incidence of bar displacement. The combined incidence of other postoperative complications was 4%: 2 wound infections and 2 hematoma formations, both needing incision and drainage. CONCLUSION: Bilateral medial stabilizer placement resulted in no incidence of bar dislocation. Return to immediate full activities after the Nuss procedure did not appear to increase the incidence of bar displacement if stabilizers were placed medially.
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Tórax em Funil , Complicações Pós-Operatórias , Humanos , Tórax em Funil/cirurgia , Masculino , Feminino , Adolescente , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Criança , Estudos Retrospectivos , Adulto Jovem , Próteses e Implantes , Procedimentos Ortopédicos/métodosRESUMO
OBJECTIVE: The present study investigates the production of mebendazole nanocrystal formulations by wet media milling. SIGNIFICANCE: Nanocrystal formulations are expected to enhance the dissolution properties of mebendazole, which possesses poor solubility, highly dependent on crystal polymorphism. METHODS: A Box-Behnken design was employed to study the effects of formulation and process variables on the nanocrystal size and ζ-potential. The optimal nanosuspensions were solidified by spay-drying and freeze-drying with and without mannitol, and the effects of the drying method on the reconstitution of the nanosuspension was studied. Additionally, their physicochemical properties were determined, while the mechanism of fracture and stabilizer adsorption were investigated by atomistic simulations. RESULTS: Poloxamer 407 is the most suitable stabilizer, while the bead size, milling speed, and stabilizer content significantly affect the diameter. The ζ-potential is affected by the stabilizer concentration depending on bead size. Energy-vector diagrams revealed a slip plane in the lattice of form C, while molecular dynamics simulations revealed strong interactions between stabilizer and crystal surface. Both drying processes induce polymorphic transformation to form A, which, however, can be partially prevented by the addition of mannitol in freeze-drying, at the expense of suspension redispersibility. The spray-dried nanosuspensions exhibited substantially enhanced dissolution profile compared to neat mebendazole, probably due to reduction of particle size, despite transformation to the unfavorable form A. CONCLUSIONS: Nanocrystal formulations exhibited significant dissolution enhancement, while experimental design and atomistic simulations provided useful insights into the mechanism of their formation and stability.
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Low restoration success in degraded drylands has promoted research efforts towards recovery of pioneer components of these ecosystems such as biocrusts. Biocrusts can stabilize soils and improve nutrient cycling to assist vegetation establishment, but their natural recovery following a disturbance may be very slow. Soil inoculation with biocrust-forming components such as cyanobacteria is widely spread to foster biocrust formation. However, the growth of induced biocrust can be constrained under field conditions due to the harsh environmental conditions in drylands. Thus, strategies to reduce abiotic stresses have to be explored to improve cyanobacteria survival and growth. In this study, we performed an outdoor experiment to analyze the effect of plant-based ameliorating strategies in combination with cyanobacteria inoculum on biocrust formation and improvement of degraded arid soil properties. These ameliorants consisted of a plant mesh made of Macrochloa tenacissima and a Plantago ovata-based stabilizer. Application of ameliorating treatments improved cyanobacteria growth (higher chlorophyll a content, lower albedo and higher NDVI) compared to the application of cyanobacteria inoculum alone. Inoculated soils showed higher aggregate stability than non-inoculated ones, but the highest soil stability was found in the soils treated with P. ovata and was also significantly increased in the soils covered by the M. tenacissima mesh compared to uncovered soils. Both the mesh and the P. ovata stabilizer increased soil organic carbon content by up to 10% and 172%, respectively, compared to soils without habitat amelioration. Microbial community composition was similar between control and inoculated soils and between the mesh covered and uncovered soils, indicating that neither cyanobacteria inoculation nor the vegetal mesh had negative effects on the native soil community. In contrast, the soil with the P. ovata stabilizer alone displayed a different composition, with up to 95% of the bacteria's relative abundance represented by Firmicutes. This effect needs to be considered when applying this stabilizer to prevent a potential alteration of the indigenous soil microbial community. This study indicates the viability of using plant-based ameliorating strategies to optimize the establishment and growth of cyanobacteria inoculum and maximize their effects on soil properties, thus contributing to advancing in the application of nature-based solutions for the restoration of degraded dryland ecosystems.
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Amyloidosis is a group of protein misfolding diseases, which include spongiform encephalopathies, Alzheimer's disease and transthyretin (TTR) amyloidosis; all of them are characterized by extracellular deposits of an insoluble fibrillar protein. TTR amyloidosis is a highly debilitating and life-threatening disease. Patients carry less stable TTR homotetramers that are prone to dissociation into non-native monomers, which in turn rapidly self-assemble into oligomers and, ultimately, amyloid fibrils. Liver transplantation to induce the production of wild-type TTR was the only therapeutic strategy until recently. A promising approach to ameliorate transthyretin (TTR) amyloidosis is based on the so-called TTR kinetic stabilizers. More than 1000 TTR stabilizers have already been tested by many research groups, but the diversity of experimental techniques and conditions used hampers an objective prioritization of the compounds. One of the most reliable and unambiguous techniques applied to determine the structures of the TTR/drug complexes is X-ray diffraction. Most of the potential inhibitors bind in the TTR channel and the crystal structures reveal the atomic details of the interaction between the protein and the compound. Here we suggest that the stabilization effect is associated with a compaction of the quaternary structure of the protein and propose a scoring function to rank drugs based on X-ray crystallography data.
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Neuropatias Amiloides Familiares , Pré-Albumina , Humanos , Pré-Albumina/metabolismo , Cristalografia por Raios X , Neuropatias Amiloides Familiares/tratamento farmacológico , Amiloide/químicaRESUMO
The small-molecule iododiflunisal (IDIF) is a transthyretin (TTR) tetramer stabilizer and acts as a chaperone of the TTR-Amyloid beta interaction. Oral administration of IDIF improves Alzheimer's Disease (AD)-like pathology in mice, although the mechanism of action and pharmacokinetics remain unknown. Radiolabeling IDIF with positron or gamma emitters may aid in the in vivo evaluation of IDIF using non-invasive nuclear imaging techniques. In this work, we report an isotopic exchange reaction to obtain IDIF radiolabeled with 18F. [19F/18F]exchange reaction over IDIF in dimethyl sulfoxide at 160 °C resulted in the formation of [18F]IDIF in 7 ± 3% radiochemical yield in a 20 min reaction time, with a final radiochemical purity of >99%. Biodistribution studies after intravenous administration of [18F]IDIF in wild-type mice using positron emission tomography (PET) imaging showed capacity to cross the blood-brain barrier (ca. 1% of injected dose per gram of tissue in the brain at t > 10 min post administration), rapid accumulation in the liver, long circulation time, and progressive elimination via urine. Our results open opportunities for future studies in larger animal species or human subjects.
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Doença de Alzheimer , Diflunisal/análogos & derivados , Humanos , Animais , Camundongos , Preparações Farmacêuticas , Distribuição Tecidual , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Pré-Albumina , Peptídeos beta-Amiloides , ExcipientesRESUMO
This study outlines a practical approach for assessing chemical instability by heating the drug-excipient binary mixtures or multi-excipient formulations at 75°C for 3 days before characterization. Differentiating itself from other excipient compatibility methods, our methodology necessitates a saturated aqueous slurry rather than arbitrarily fixed water content. This allows bulk and surface water in the excipient to contribute to drug degradation. The synergistic impact of surface water and elevated temperature expedites degradation kinetics, resulting in accelerated data generation. Among excipient compatibility methods available, our method is quantitative and merges with traditionally used methodologies. The devised nomograph enables extrapolation of shelf life at 20°C from experimental data obtained at 75°C. This methodology also helped identify stabilizers for the drug NVS-1 where traditional excipient compatibility programs had failed. Incorporation of monovalent salts, such as sodium/potassium chloride and sodium bicarbonate at 5% w/w, significantly enhanced the chemical stability of NVS-1, ensuring stable tablet formulations. Our hypothesis posits that stabilization is due to increased ionic strength in the slurry, which stabilizes an induced dipole within the polar NVS-1 drug. Additionally, the presence of ions in the moisture layer is anticipated to stabilize π-π stacking of two planar aromatic NVS-1 molecules. The expedited generation of experimental data allowed the identification of inorganic salts to supplement a standard excipient compatibility screening panel. Considering the economic implications of stability testing methodologies in effort, cost, and duration, a faster turnaround in chemical stability data enhances formulation selection. This ultimately facilitates the development of drug formulations with greater efficiency without delays.
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Excipientes , Sais , Suplementos Nutricionais , Calefação , ÁguaRESUMO
Inspired by classical polar codes, whose coding rate can asymptotically achieve the Shannon capacity, researchers are trying to find their analogs in the quantum information field, which are called quantum polar codes. However, no one has designed a quantum polar coding scheme that applies to quantum computing yet. There are two intuitions in previous research. The first is that directly converting classical polar coding circuits to quantum ones will produce the polarization phenomenon of a pure quantum channel, which has been proved in our previous work. The second is that based on this quantum polarization phenomenon, one can design a quantum polar coding scheme that applies to quantum computing. There are several previous work following the second intuition, none of which has been verified by experiments. In this paper, we follow the second intuition and propose a more reasonable quantum polar stabilizer code construction algorithm than any previous ones by using the theory of stabilizer codes. Unfortunately, simulation experiments show that even the stabilizer codes obtained from this more reasonable construction algorithm do not work, which implies that the second intuition leads to a dead end. Based on the analysis of why the second intuition does not work, we provide a possible future direction for designing quantum stabilizer codes with a high coding rate by borrowing the idea of classical polar codes. Following this direction, we find a class of quantum stabilizer codes with a coding rate of 0.5, which can correct two of the Pauli errors.
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The color of grape juice is an important acceptance attribute by consumers, but it suffers losses during storage. The use of commercial antioxidants has limitations because the concept of a "100% natural drink" of Brazilian legislation. This work characterized Brazilian grape seeds, and the cultivar extract with the greatest potential was encapsulated in arabic-gum (encapsulated extract-EE) to evaluate the color stabilizing capacity. The EE used in the grape juice was compared with the commercial antioxidants sulphite and enological tannin during storage (150 days). The BRS Magna and BRS Violeta grape seeds had the highest phenolic content, and the EE showed high catechin (4108 mg/kg), epicatechin (1161 mg/kg) and procyanidin-B2 (905 mg/kg) values. Sulfite was found to be the best color stabilizer. The use of EE (0.5 g/L) in grape juice improved color stability and anthocyanin stability. It was demonstrated that encapsulated grape seed extract has color stabilizing potential and that Brazilian grape seeds are a raw material of high technological value. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05956-8.
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Stroke is the most common cause of long-term disability and places a high economic burden on the global healthcare system. Functional outcomes from stroke are largely determined by the extent of ischemic injury, however, there is growing recognition that systemic inflammatory responses also contribute to outcomes. Mast cells (MCs) rapidly respond to injury and release histamine (HA), a pro-inflammatory neurotransmitter that enhances inflammation. The gut serves as a major reservoir of HA. We hypothesized that cromolyn, a mast cell stabilizer that prevents the release of inflammatory mediators, would decrease peripheral and central inflammation, reduce MC trafficking to the brain, and improve stroke outcomes. We used the transient middle cerebral artery occlusion (MCAO) model of ischemic stroke in aged (18 mo) male mice to investigate the role of MC in neuroinflammation post-stroke. After MCAO we treated mice with 25 mg/kg body weight of cromolyn (MC stabilizer) by oral gavage. Cromolyn was administered at 3 h, 10 h, 24 h and every 24 h for 3 days post-stroke. Three control groups were used. One group underwent a sham surgery and was treated with cromolyn, one received sham surgery with PBS vehicle and the third underwent MCAO with PBS vehicle. Mice were euthanized at 24 h and 3 days post-stroke. Cromolyn administration significantly reduced MC numbers in the brain at both 24 h and 3 days post-stroke. Infarct volume was not significantly different between groups, however improved functional outcomes were seen at 3 days post-stroke in mice that received cromolyn. Treatment with cromolyn reduced plasma histamine and IL-6 levels in both the 24-h and 3-day cohorts. Gut MCs numbers were significantly reduced after cromolyn treatment at 24 h and 3 days after stroke. To determine if MC trafficking from the gut to the brain occurred after injury, GFP+MCs were adoptively transferred to c-kit-/- MC knock-out animals prior to MCAO. 24 h after stroke, elevated MC recruitment was seen in the ischemic brain. Preventing MC histamine release by cromolyn improved gut barrier integrity and an improvement in stroke-induced dysbiosis was seen with treatment. Our results show that preventing MC histamine release possesses prevents post-stroke neuroinflammation and improves neurological and functional outcomes.
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Liberação de Histamina , Acidente Vascular Cerebral , Humanos , Camundongos , Masculino , Animais , Mastócitos , Cromolina Sódica/farmacologia , Cromolina Sódica/uso terapêutico , Histamina , Doenças Neuroinflamatórias , Acidente Vascular Cerebral/complicações , Inflamação/tratamento farmacológico , Inflamação/etiologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , IsquemiaRESUMO
Though cryopreservation of cell fractions is widely used in flow cytometry studies, whole blood cryopreservation is more challenging due to the presence of erythrocytes and effects of fixatives commonly used for preservation. Here, we evaluated and compared head-to-head the performance of four commercial whole blood cryopreservation kits; (1) Cytodelics, (2) Stable-Lyse V2 and Stable-Store V2 (SLSS-V2), (3) Proteomic stabilizer (PROT-1), and (4) Transfix. We found that PROT-1, Transfix, and Cytodelics maintained the distribution of major leukocyte subsets-granulocytes, T cells, natural killer cells, and B cells, on a comparable level to unpreserved samples, despite the attenuation of fluorescence intensities in flow cytometric assays. Moreover, these three stabilizers also maintained the activated phenotypes of neutrophils upon stimulation with N-formylmethionyl-leucyl-phenylalanine and lipopolysaccharides. The upregulation of adhesion molecules (CD11b), Fc receptors (CD16), and granule proteins (CD66b), as well as the shedding of surface L-selectin (CD62L), was conserved most efficiently in PROT-1 and Cytodelics when compared to samples only treated with erythrocyte lysing. However, none of the stabilizers provided a reliable detection of CCR7 for accurate quantification of T cell maturation stages. We also evaluated the performance of Cytodelics in longitudinal clinical samples obtained from acute COVID-19 patients, where it allowed reliable detection of lymphopenia and granulocyte expansion. These results support the feasibility of whole blood cryopreservation for immunophenotyping by flow cytometry, particularly in longitudinal studies. In conclusion, the performance of different stabilizers is variable and therefore the choice of stabilizers should depend on cell type of interest, as well as antibody clones and experimental design of each study.
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COVID-19 , Proteômica , Humanos , Citometria de Fluxo , Leucócitos , GranulócitosRESUMO
The near-infrared (NIR) light-absorbing AgBiS2 nanoparticles can be excited by single-wavelength light, which is the primary characteristic of a photo responsive platform. Chemical synthesis of nanomaterials inevitably requires long-chain organic surfactants or polymers to stabilize them in the nano regime. These stabilizing molecules barricade the interaction of nanomaterials with biological cells. We have produced stabilizer-free (sf-AgBiS2 ) and polymer-coated (PEG-AgBiS2 ) nanoparticles; and assessed their NIR mediated anticancer and antibacterial activity to evaluate the effect of stabilizers. sf-AgBiS2 showed better antibacterial activity against Gram-positive Staphylococcus aureus (S. aureus) and displayed excellent cytotoxicity against HeLa cells and live 3-D tumour spheroids compared to PEG-AgBiS2 both in presence and absence of NIR radiation. The photothermal therapy (PTT) results illustrated the tumour ablation ability of sf-AgBiS2 , which converted light into heat effectively up to 53.3 °C under NIR irradiation. This work demonstrates the importance of synthesizing stabilizer-free nanoparticles to produce safe and highly active PTT agents.
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Nanopartículas , Fototerapia , Humanos , Fototerapia/métodos , Células HeLa , Staphylococcus aureus , Nanopartículas/química , Antibacterianos/farmacologiaRESUMO
BACKGROUND: Relatively few studies have explored the differential contributions of the accumulative dosage of psychotropic medications on mortality in patients with schizophrenia. METHODS: We aimed to explore the effects of the exposure dosage of psychotropic medications on mortality during a follow-up period of 5 years with a national cohort of individuals with schizophrenia in 2010. Causes of death were linked through Taiwan's National Mortality Registry. The mean defined daily dose of antipsychotics, antidepressants, mood stabilizers, and sedative-hypnotics, were calculated and survival analyses were conducted. RESULTS: A total of 102 964 individuals (54 151 men, 52.59%) with schizophrenia were included. Compared to patients with no exposure to antipsychotics, those with antipsychotic exposure had better survival outcomes, regardless of antipsychotic dosage. Antidepressant exposure, in low and moderate dosage, was associated with decreased all-cause mortality; exposure to mood stabilizers appeared to be associated with an increase in all-cause mortality. Although 89.7% of the patients had been prescribed sedative-hypnotics, exposure to sedative-hypnotics was associated with dose-related increased mortality risk [hazard ratio (HR) in low dose group: 1.16, 95% confidence interval (CI) 1.07-1.27; HR in moderate dose: 1.32, 95% CI 1.21-1.44; HR in high dose: 1.83, 95% CI 1.67-2.01)]. CONCLUSIONS: The results indicate that in the treatment of schizophrenia, antipsychotics and antidepressants are associated with lower mortality when using adequate dosages and mood stabilizers and sedative-hypnotics with higher mortality compared with no use. Furthermore, exposure to sedative-hypnotics is associated with a dose-related increased mortality risk which warrants clinical attention and further study.