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BACKGROUND AND AIMS: To investigate the efficacy and feasibility of three different 8 h time-restricted eating (TRE) schedules (i.e., early, late, and self-selected) compared to each other and to a usual-care (UC) intervention on visceral adipose tissue (VAT) and cardiometabolic health in men and women. METHODS AND RESULTS: Anticipated 208 adults (50% women) aged 30-60 years, with overweight/obesity (25 ≤ BMI<40 kg/m2) and with mild metabolic impairments will be recruited for this parallel-group, multicenter randomized controlled trial. Participants will be randomly allocated (1:1:1:1) to one of four groups for 12 weeks: UC, early TRE, late TRE or self-selected TRE. The UC group will maintain their habitual eating window and receive, as well as the TRE groups, healthy lifestyle education for weight management. The early TRE group will start eating not later than 10:00, and the late TRE group not before 13:00. The self-selected TRE group will select an 8 h eating window before the intervention and maintain it over the intervention. The primary outcome is changes in VAT, whereas secondary outcomes include body composition and cardiometabolic risk factors. CONCLUSION: This study will determine whether the timing of the eating window during TRE impacts its efficacy on VAT, body composition and cardiometabolic risk factors and provide insights about its feasibility.
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Doenças Cardiovasculares , Gordura Intra-Abdominal , Adulto , Masculino , Humanos , Feminino , Composição Corporal , Fatores de Risco Cardiometabólico , Escolaridade , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Jejum , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como AssuntoRESUMO
Among antihyperglycemic drugs used for treating diabetes, α-glucosidase inhibitors generate the least adverse effects. This contribution aimed to evaluate the potential antidiabetic activity of Rumex crispus L. by testing its in vitro α-glucosidase inhibition and in vivo antihyperglycemic effects on rats with streptozotocin (STZ)-induced diabetes. Better inhibition of α-glucosidase was found with the methanol extract versus the n-hexane and dichloromethane extracts. The methanol extract of the flowers (RCFM) was more effective than that of the leaves (RCHM), with an IC50 of 7.3 ± 0.17 µg/mL for RCFM and 112.0 ± 1.23 µg/mL for RCHM. A bioactive fraction (F89s) also showed good α-glucosidase inhibition (IC50 = 3.8 ± 0.11 µg/mL). In a preliminary study, RCHM and RCFM at 150 mg/kg and F89s at 75 mg/kg after 30 days showed a significant effect on hyperglycemia, reducing glucose levels (82.2, 80.1, and 84.1%, respectively), and improved the lipid, renal, and hepatic profiles of the rats, comparable with the effects of metformin and acarbose. According to the results, the activity of R. crispus L. may be mediated by a diminished rate of disaccharide hydrolysis, associated with the inhibition of α-glucosidase. Thus, R. crispus L. holds promise for the development of auxiliary drugs to treat diabetes mellitus.
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Diabetes Mellitus Experimental , Rumex , Ratos , Animais , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , alfa-Glucosidases , Metanol , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/uso terapêutico , Folhas de Planta , Diabetes Mellitus Experimental/tratamento farmacológico , FloresRESUMO
Current antidiabetic drugs have severe side effects, which may be minimized by new selective molecules that strongly inhibit α-glucosidase and weakly inhibit α-amylase. We have synthesized novel alkoxy-substituted xanthones and imidazole-substituted xanthones and have evaluated them for their in silico and in vitro α-glucosidase and α-amylase inhibition activity. Compounds 6c, 6e, and 9b promoted higher α-glucosidase inhibition (IC50 = 16.0, 12.8, and 4.0 µM, respectively) and lower α-amylase inhibition (IC50 = 76.7, 68.1, and >200 µM, respectively) compared to acarbose (IC50 = 306.7 µM for α-glucosidase and 20.0 µM for α-amylase). Contrarily, derivatives 10c and 10f showed higher α-amylase inhibition (IC50 = 5.4 and 8.7 µM, respectively) and lower α-glucosidase inhibition (IC50 = 232.7 and 145.2 µM, respectively). According to the structure-activity relationship, attaching 4-bromobutoxy or 4'-chlorophenylacetophenone moieties to the 2-hydroxy group of xanthone provides higher α-glucosidase inhibition and lower α-amylase inhibition. In silico studies suggest that these scaffolds are key in the activity and interaction of xanthone derivatives. Enzymatic kinetics studies showed that 6c, 9b, and 10c are mainly mixed inhibitors on α-glucosidase and α-amylase. In addition, drug prediction and ADMET studies support that compounds 6c, 9b, and 10c are candidates with antidiabetic potential.
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Inibidores de Glicosídeo Hidrolases , Xantonas , Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , alfa-Glucosidases/metabolismo , alfa-Amilases , Hipoglicemiantes/farmacologia , Relação Estrutura-Atividade , Imidazóis/farmacologia , Xantonas/farmacologia , Estrutura MolecularRESUMO
Bipolar disorder is a highly heritable illness, associated with alterations of brain structure. As such, identification of genes influencing inter-individual differences in brain morphology may help elucidate the underlying pathophysiology of bipolar disorder (BP). To identify quantitative trait loci (QTL) that contribute to phenotypic variance of brain structure, structural neuroimages were acquired from family members (n = 527) of extended pedigrees heavily loaded for bipolar disorder ascertained from genetically isolated populations in Latin America. Genome-wide linkage and association analysis were conducted on the subset of heritable brain traits that showed significant evidence of association with bipolar disorder (n = 24) to map QTL influencing regional measures of brain volume and cortical thickness. Two chromosomal regions showed significant evidence of linkage; a QTL on chromosome 1p influencing corpus callosum volume and a region on chromosome 7p linked to cortical volume. Association analysis within the two QTLs identified three SNPs correlated with the brain measures.
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Transtorno Bipolar , Transtorno Bipolar/genética , Encéfalo/diagnóstico por imagem , Ligação Genética/genética , Humanos , Linhagem , Fenótipo , Locos de Características Quantitativas/genéticaRESUMO
BACKGROUND: Disturbed sleep and activity are prominent features of bipolar disorder type I (BP-I). However, the relationship of sleep and activity characteristics to brain structure and behavior in euthymic BP-I patients and their non-BP-I relatives is unknown. Additionally, underlying genetic relationships between these traits have not been investigated. METHODS: Relationships between sleep and activity phenotypes, assessed using actigraphy, with structural neuroimaging (brain) and cognitive and temperament (behavior) phenotypes were investigated in 558 euthymic individuals from multi-generational pedigrees including at least one member with BP-I. Genetic correlations between actigraphy-brain and actigraphy-behavior associations were assessed, and bivariate linkage analysis was conducted for trait pairs with evidence of shared genetic influences. RESULTS: More physical activity and longer awake time were significantly associated with increased brain volumes and cortical thickness, better performance on neurocognitive measures of long-term memory and executive function, and less extreme scores on measures of temperament (impulsivity, cyclothymia). These associations did not differ between BP-I patients and their non-BP-I relatives. For nine activity-brain or activity-behavior pairs there was evidence for shared genetic influence (genetic correlations); of these pairs, a suggestive bivariate quantitative trait locus on chromosome 7 for wake duration and verbal working memory was identified. CONCLUSIONS: Our findings indicate that increased physical activity and more adequate sleep are associated with increased brain size, better cognitive function and more stable temperament in BP-I patients and their non-BP-I relatives. Additionally, we found evidence for pleiotropy of several actigraphy-behavior and actigraphy-brain phenotypes, suggesting a shared genetic basis for these traits.
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Transtorno Bipolar/genética , Transtorno Bipolar/fisiopatologia , Transtorno Bipolar/psicologia , Encéfalo/patologia , Sono , Actigrafia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cognição , Família , Feminino , Humanos , Padrões de Herança/genética , Modelos Lineares , Masculino , Memória de Curto Prazo , Pessoa de Meia-Idade , Linhagem , Fenótipo , Temperamento , Adulto JovemRESUMO
Oocyte maturation defect is a challenging situation in the management of infertility, the etiology may be related to endocrine causes, protocols used in ovarian stimulation, oocyte intrinsic defects or procedures in embryology laboratory. We report three Mexican females in treatment for primary infertility with non-mature oocytes after ovary stimulation and oocyte capture in whom a genetic diagnosis of TUBB8-oocyte maturation defect was revealed by exome sequencing. Two couples achieved pregnancies though oocyte donation after establishing the genetic etiology. Our results expand the role of TUBB8-disorders in patients of non-Asian ethnicity. Oocyte maturation defects of monogenic origin are a growing group of disorders that endocrinologists and reproductive medicine specialists should be aware in order to provide referral to genetics for establish a correct and opportune diagnosis.
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Doenças Genéticas Inatas/terapia , Infertilidade Feminina/diagnóstico , Infertilidade Feminina/terapia , Oogênese/genética , Tubulina (Proteína)/genética , Adulto , Análise Mutacional de DNA , Feminino , Doenças Genéticas Inatas/diagnóstico , Doenças Genéticas Inatas/epidemiologia , Humanos , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/genética , México , Mutação , Linhagem , Gravidez , Prognóstico , Técnicas de Reprodução Assistida/estatística & dados numéricos , Resultado do TratamentoRESUMO
Abnormalities in sleep and circadian rhythms are central features of bipolar disorder (BP), often persisting between episodes. We report here, to our knowledge, the first systematic analysis of circadian rhythm activity in pedigrees segregating severe BP (BP-I). By analyzing actigraphy data obtained from members of 26 Costa Rican and Colombian pedigrees [136 euthymic (i.e., interepisode) BP-I individuals and 422 non-BP-I relatives], we delineated 73 phenotypes, of which 49 demonstrated significant heritability and 13 showed significant trait-like association with BP-I. All BP-I-associated traits related to activity level, with BP-I individuals consistently demonstrating lower activity levels than their non-BP-I relatives. We analyzed all 49 heritable phenotypes using genetic linkage analysis, with special emphasis on phenotypes judged to have the strongest impact on the biology underlying BP. We identified a locus for interdaily stability of activity, at a threshold exceeding genome-wide significance, on chromosome 12pter, a region that also showed pleiotropic linkage to two additional activity phenotypes.
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Transtorno Bipolar/genética , Transtorno Bipolar/fisiopatologia , Ritmo Circadiano , Sono , Actigrafia , Cromossomos Humanos Par 1/genética , Família , Feminino , Humanos , Padrões de Herança/genética , Escore Lod , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Característica Quantitativa HerdávelRESUMO
With the purpose of expanding the structural variety of chemical compounds available as pharmacological tools for the treatment of Alzheimer's disease, we synthesized and evaluated a novel series of indole-benzoxazinones (Family I) and benzoxazine-arylpiperazine derivatives (Family II) for potential human acetylcholinesterase (hAChE) inhibitory properties. The most active compounds 7a and 7d demonstrated effective inhibitory profiles with Ki values of 20.3 ± 0.9 µM and 20.2 ± 0.9 µM, respectively. Kinetic inhibition assays showed non-competitive inhibition of AChE by the tested compounds. According to our docking studies, the most active compounds from both series (Families I and II) showed a binding mode similar to donepezil and interact with the same residues.
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Acetilcolinesterase/efeitos dos fármacos , Benzoxazinas/farmacologia , Inibidores da Colinesterase/farmacologia , Piperazinas/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Benzoxazinas/síntese química , Benzoxazinas/química , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Donepezila , Desenho de Fármacos , Humanos , Indanos/farmacologia , Simulação de Acoplamento Molecular , Piperazinas/síntese química , Piperazinas/química , Piperidinas/farmacologia , Ligação Proteica , Relação Estrutura-AtividadeRESUMO
The effect of ethanol (EtOH) on the gut immune system was analyzed using an experimental model previously described, where EtOH was provided ad libitum in the drinking water in a 20% w/v concentration for up to 12weeks. Dendritic cells, T cells and macrophages were analyzed in Peyer's patches and the small intestines using flow cytometry. Cytokine and immunoglobulin levels were analyzed in sera, feces, and homogenates from small and large intestines and lungs. Decreases in the proportion of T cells and alterations in dendritic cells and macrophages were observed after EtOH treatment. Levels of immunoglobulin A (IgA) increased in tissue homogenates but decreased in small intestine fecal contents. Meanwhile poly-immunoglobulin receptor (pIgR) levels decreased in tissue homogenates and fecal contents. Levels of cytokines associated with the regulation of pIgR expression decreased for IL-10 and TGF-ß, and increased for IFN-γ and IL-17 in the small intestine. The data indicate that chronic EtOH consumption disrupts the homeostasis of the mucosal immune system by altering the phenotype and functionality of multiple immune cell types, leading to a diminished secretion of SIgA, due to pIgR expression decreased.
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Alcoolismo/imunologia , Imunoglobulina A Secretora/imunologia , Receptores de Imunoglobulina Polimérica/imunologia , Animais , Citocinas/imunologia , Fezes/química , Feminino , Intestinos/imunologia , Leucócitos/imunologia , Masculino , Camundongos Endogâmicos C57BLRESUMO
The application of pectinases in industrial olive-oil processes is restricted by its production cost. Consequently, new fungal strains able to produce higher pectinase titers are required. The aim of this work was to study the capability of Aspergillus giganteus NRRL10 to produce pectinolytic enzymes by SSF and evaluate the application of these in olive-oil extraction. A. giganteus was selected among 12 strains on the basis of high pectinolytic activity and stability. A mixture composed by wheat bran, orange, and lemon peels was selected as the best substrate for enzyme production. Statistical analyses of the experimental design indicated that pH, temperature, and CaCl2 are the main factors that affect the production. Subsequently, different aeration flows were tested in a tray reactor; the highest activity was achieved at 20 L min-1 per kilogram of dry substrate (kgds). Finally, the pectinolytic enzymes from A. giganteus improved the oil yield and rheological characteristics without affecting oil chemical properties.
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Aspergillus/enzimologia , Fermentação , Manipulação de Alimentos , Azeite de Oliva , Poligalacturonase/biossíntese , Aspergillus/classificação , Reatores Biológicos , Fenômenos Químicos , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Microbiologia Industrial , TemperaturaRESUMO
Recent theories regarding the pathophysiology of bipolar disorder suggest contributions of both neurodevelopmental and neurodegenerative processes. While structural neuroimaging studies indicate disease-associated neuroanatomical alterations, the behavioural correlates of these alterations have not been well characterized. Here, we investigated multi-generational families genetically enriched for bipolar disorder to: (i) characterize neurobehavioural correlates of neuroanatomical measures implicated in the pathophysiology of bipolar disorder; (ii) identify brain-behaviour associations that differ between diagnostic groups; (iii) identify neurocognitive traits that show evidence of accelerated ageing specifically in subjects with bipolar disorder; and (iv) identify brain-behaviour correlations that differ across the age span. Structural neuroimages and multi-dimensional assessments of temperament and neurocognition were acquired from 527 (153 bipolar disorder and 374 non-bipolar disorder) adults aged 18-87 years in 26 families with heavy genetic loading for bipolar disorder. We used linear regression models to identify significant brain-behaviour associations and test whether brain-behaviour relationships differed: (i) between diagnostic groups; and (ii) as a function of age. We found that total cortical and ventricular volume had the greatest number of significant behavioural associations, and included correlations with measures from multiple cognitive domains, particularly declarative and working memory and executive function. Cortical thickness measures, in contrast, showed more specific associations with declarative memory, letter fluency and processing speed tasks. While the majority of brain-behaviour relationships were similar across diagnostic groups, increased cortical thickness in ventrolateral prefrontal and parietal cortical regions was associated with better declarative memory only in bipolar disorder subjects, and not in non-bipolar disorder family members. Additionally, while age had a relatively strong impact on all neurocognitive traits, the effects of age on cognition did not differ between diagnostic groups. Most brain-behaviour associations were also similar across the age range, with the exception of cortical and ventricular volume and lingual gyrus thickness, which showed weak correlations with verbal fluency and inhibitory control at younger ages that increased in magnitude in older subjects, regardless of diagnosis. Findings indicate that neuroanatomical traits potentially impacted by bipolar disorder are significantly associated with multiple neurobehavioural domains. Structure-function relationships are generally preserved across diagnostic groups, with the notable exception of ventrolateral prefrontal and parietal association cortex, volumetric increases in which may be associated with cognitive resilience specifically in individuals with bipolar disorder. Although age impacted all neurobehavioural traits, we did not find any evidence of accelerated cognitive decline specific to bipolar disorder subjects. Regardless of diagnosis, greater global brain volume may represent a protective factor for the effects of ageing on executive functioning.
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Transtorno Bipolar/genética , Transtorno Bipolar/patologia , Encéfalo/patologia , Predisposição Genética para Doença , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Adulto JovemRESUMO
A novel design of a sodium-ion cell is proposed based on the use of nanocrystalline thin films composed of transition metal oxides. X-ray diffraction, Raman spectroscopy and electron microscopy were helpful techniques to unveil the microstructural properties of the pristine nanostructured electrodes. Thus, Raman spectroscopy revealed the presence of amorphous NiO, α-Fe2 O3 (hematite) and γ-Fe2 O3 (maghemite). Also, this technique allowed the calculation of an average particle size of 23.4 Å in the amorphous carbon phase in situ generated on the positive electrode. The full sodium-ion cell performed with a reversible capacity of 100 mA h g(-1) at C/2 with an output voltage of about 1.8 V, corresponding to a specific energy density of about 180 W h kg(-1) . These promising electrochemical performances allow these transition metal thin films obtained by electrochemical deposition to be envisaged as serious competitors for future negative electrodes in sodium-ion batteries.
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Solid electrolytes are crucial in the development of advanced lithium batteries and related technologies. Orthorhombic Li2NaPO4 (nalipoite) was synthesized, and its ionic conductivity compared very favorably with that of Li3PO4. The potential applicability of Li(3-x)Na(x)PO4 as a lithium ion solid electrolyte was investigated for first time. First-principles DFT calculations were used to evaluate the possibilities of preparing other crystal structures.
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A 7-month-old intact female bearded collie dog was admitted after a 2-week history of progressive cough, inappetence, and lethargy, with no response to previous treatment with doxycycline and steroids. Mild attenuation of lung sounds in the right middle hemithorax was the only abnormality detected on physical examination. Abdominal ultrasound and thoracic radiographs were performed and revealed multifocally distributed nodules and masses, well-circumscribed and of variable size in the kidneys and pulmonary parenchyma. Ultrasound-guided fine needle aspirates of the renal and pulmonary masses were taken. A cytologic evaluation of these lesions pointed towards a malignant mesenchymal neoplasia. Euthanasia was elected due to the poor prognosis and rapid progression. The post-mortem histopathology, a positive result to IBA1 immunoperoxidase staining, and a lack of detection of infectious agents, and negative E-cadherin immunostaining enabled the final diagnosis of a disseminated histiocytic sarcoma. We report an atypical form, both in breed and age, of canine disseminated histiocytic sarcoma. While all breeds can be affected, there is a clear predisposition in some, and no cases have been previously described in bearded collies. Moreover, to the authors' knowledge, this is the youngest dog with this histiocytic disorder described to date. Disseminated histiocytic sarcoma should be considered as a differential diagnosis of multinodular tumors in dogs, regardless of the anatomic location and age of the dogs, even in puppies.
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Doenças do Cão , Sarcoma Histiocítico , Sarcoma , Cães , Animais , Feminino , Sarcoma Histiocítico/patologia , Sarcoma Histiocítico/veterinária , Sarcoma/patologia , Sarcoma/veterinária , Biópsia por Agulha Fina/veterinária , Histiócitos/patologia , Doenças do Cão/diagnósticoRESUMO
The antibacterial activity (ABA) of honey is associated with the generation of reactive oxygen species (ROS), where polyphenols (PFs) play a key role due to their pro-oxidant action modulated by metallic cations. In this work, the contents of PFs, H2O2, OH radicals, Cu, Fe, Mn, Zn, and ABA against Staphylococcus epidermidis and Pseudomonas aeruginosa were determined in honeys from central Chile. Then, their relationships were evaluated through partial least squares regression. The average contents of phenolic acids, flavonoids and metals in honey ranged from 0.4 to 4 µg/g, 0.3-1.5 µg/g and 3-6 µg/g, respectively. All honeys showed accumulation of H2O2 (1-35 µg/g) and OH radicals. The PLS showed that gallic acid, p-coumaric acid, chrysin, kaempferol, Fe, and Mn stimulate the generation of ROS. Quercetin, Cu, and Zn showed marginal antioxidant effects. PFs favor the ABA of honey against both bacteria and H2O2 against S. epidermidis.
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Mel , Espécies Reativas de Oxigênio , Mel/análise , Peróxido de Hidrogênio , Fenóis/análise , Antioxidantes , Minerais , Antibacterianos/farmacologiaRESUMO
Background: Ruminococcus gnavus (R. Gnavus) is an anaerobic Gram-positive coccus, common commensal of the gastrointestinal tract of animals and humans. Anaerobic organisms as etiologic agents of bone and joint infections (BJI) are uncommon and frequently underestimated. New technologies, such as mass spectrometry techniques and molecular techniques like 16S rRNA, allow for more efficient diagnosis of these anaerobic bacteria. We present the first case report of deep surgical site infection (SSI) due to R. Gnavus, following spinal surgery. Case Description: We report the case of a deep SSI caused by R. Gnavus following posterior spinal instrumentation in an 81-year-old woman. The patient underwent extension of her previous fusion L2-L5, due to adjacent segment disease (ASD). We performed a T10 to S2-alar-iliac instrumentation. During the postoperative period, the patient presented with a paralytic ileus that required the placement of a nasogastric tube followed by gastrointestinal bleeding and two gastroscopies. Subsequently the patient showed signs of deep SSI. We performed surgical irrigation and debridement. All six cultures in anaerobic media showed short Gram-positive diplococci, using matrix-assisted laser desorption/ionization time of flight mass spectrometry (Maldi-TOF MS) all six strains were identified as R. Gnavus. The patient was treated with amoxicilin 1 g/8 h and ciprofloxacin 750 mg/12 h for 4 weeks. Six months postoperative, she was asymptomatic. Conclusions: As is the case with our patient, all previously described cases of R. Gnavus infection had a history of intestinal disease or immunosupression. We believe the isolation of R. Gnavus should raise the possibility of intestinal injury. Immunosuppression is also an important risk factor for the development of R. Gnavus infection.
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Background: Cerebrospinal fluid leakage can cause abducens nerve palsy (ANP) secondary to downward brain traction, caused by intracranial hypotension. We present the first case after cervical fixation and fusion with spinal cord decompression. Case Description: We present a 65-year-old male, who undergone C5-C6 decompression by laminectomy and C3-T2 fixation and fusion, without intraoperative complications. Two months later, the patient referred a 2-week history of diplopia, with no other accompanying symptom. Clinical examination revealed a lack of lateral gaze of the left eye. Cervical MRI disclosed findings compatible with pseudomeningocele. Given the time of evolution, the subacute clinical findings and the absence of image or clinical data of infection or intracranial hypotension, we decided to perform conservative treatment. We submitted the patient to periodic clinical examinations and we confirmed progressive clinical improvement of diplopia, in association with neurologic and ophthalmologic specialists. At this time, six months after surgery, the patient is asymptomatic. The swelling has significantly decreased in size. Control MRI revealed no growth of the pseudomeningocele. Conclusions: ANP secondary to intracranial hypotension after cervical spine surgery requires immediate imaging tests and clinical evaluation from neurology and ophthalmology specialists. Management can be conservative, as long as diplopia is the only clinical and radiological finding and wound does not show signs of infection.
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Grape pomace (GP) is a by-product resulting from the winemaking process and its potential use as a source of bioactive compounds is well known. The GP bioactive compounds can be retained in the well-known polyvinylpolypyrrolidone (PVPP), industrially used in the clarification and stabilization of wine and other drinks. Thus, the polyphenolic compounds (PC) from the Chilean Carménère, Cabernet Sauvignon, and Merlot GP were extracted, and their compositions and antioxidant capacities (ORAC-FL) were determined. In addition, the retention capacity of the PC on PVPP (PC-PVPP) was evaluated. The bioactivities of GP extracts and PC-PVPP were estimated by the agar plate inhibition assay against pathogenic microorganisms. Results showed a high amount of TPC and antioxidant capacity in the three ethanolic GPs extracts. Anthocyanins, flavan-3-ol, and flavonols were the most abundant compounds in the GP extract, with retentions between 70 and 99% on PVPP. The GP extracts showed inhibition activity against B. cereus and P. syringae pv. actinidiae but the GP-PVPP had no antimicrobial activity. The high affinity of the identified PCs from GPs on PVPP polymer could allow the design of new processes and by-products for the food or cosmeceutical industry, promoting a circular economy by reducing and reusing wastes (GPs and PVPP) and organic solvents.
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Silver nanoclusters of five atoms (Ag5) display outstanding catalytic activities for the deactivation of radicals. Using 2,2-diphenyl-1picrylhydrazyl (DPPH) radical as a model system, we observed a fast radical reduction to DPPH anions using only [Ag5] 3 to 4 orders of magnitude less than [DPPH]. Moreover, nanoclusters remain stable at the end of the reaction, and can deactivate again DPPH radicals at the same rate, indicating that they act as anti-radical catalysts. The radical scavenger catalytic activity of Ag5 proceeds selectively through the oxidation of methanol (used to dissolve the radical) to formaldehyde, which is supported by DFT calculations. The obtained catalytic rate constants are almost 2 orders of magnitude higher than oxidases, and more than 4 orders of magnitude larger than graphene quantum dots. We also show that Ag5 not only catalyze the reduction of radicals but also their oxidation, promoting the inhibition of the autoxidation mechanisms of hydrocarbon polymers, which are very sensitive to the presence of radicals. For this purpose, thin films of two industrially relevant polymers (polyisoprene and acrylonitrile-butadienestyrene copolymer), were exposed to standard simulated photo-ageing conditions in the presence of Ag5. Using Attenuated Total Reflection-FTIR and DFT modeling we observed that, although Ag5 nanoclusters, with ≈ 15% surface coverage, do not totally inhibit the oxidation, they favour a decomposition that yields inactive products, in contrast with the more detrimental ketone formation pathway. These results not only open new possibilities for developing a post-process inhibition of polymer degradation, for which nowadays there are no efficient procedures, but also, they could be used as very efficient dual-redox catalytic radical scavengers for different industrial or biomedical purposes.