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BACKGROUND: The process of vascular development is essential for shaping complex craniofacial structures. Investigating the interplay between vascular development and orofacial morphogenesis holds critical importance in clinical practice and contributes to advancing our comprehension of (vascular) developmental biology. New insights into specific vascular developmental pathways will have far-reaching implications across various medical disciplines, enhancing clinical understanding, refining surgical techniques, and elucidating the origins of congenital abnormalities. Embryonic development of the craniofacial vasculature remains, however, under-exposed in the current literature. We imaged and created 3-dimensional (D) reconstructed images of the craniofacial arterial system from two early-stage human embryonic samples. OBJECTIVE: The aim of this study was to investigate the vascular development of the craniofacial region in early-stage human embryos, with a focus on understanding the interplay between vascular development and orofacial morphogenesis. MATERIALS AND METHODS: Reconstructions (3-D) were generated from high-resolution diffusible iodine-based contrast-enhanced computed tomography (diceCT) images, enabling visualization of the orofacial arterial system in human embryonic samples of Carnegie stages (CS) 14 and 18 from the Dutch Fetal Biobank, corresponding to weeks 7 and 8.5 of gestation. RESULTS: From two human embryonic samples (ages CS 14 and 18), the vascular development of the orofacial region at two different stages of development was successfully stained with B-Lugol and imaged using a micro-computed tomography (micro-CT) scanner with resolutions of 2.5-µm and 9-µm voxel sizes, respectively. Additionally, educational 3-D reconstructions of the orofacial vascular system were generated using AMIRA 2021.2 software. CONCLUSION: Micro-CT imaging is an effective strategy for high-resolution visualization of vascular development of the orofacial region in human embryonic samples. The generated interactive 3-D educational models facilitate better understanding of the development of orofacial structures.
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OBJECTIVE: The diagnosis and management of Superior Canal Dehiscence Syndrome (SCDS) with concomitant otosclerosis can be a challenge. Otosclerosis can mask SCDS symptoms and stapes surgery may reveal or exacerbate vestibular symptoms. Our aim is to present four cases of SCDS with concomitant otosclerosis and thereby informing the reader about the possibility of this dual occurrence and its implications for treatment. CASES: Four patients with SCDS and concomitant otosclerosis are presented. Two patients underwent surgical treatment for both SCDS and otosclerosis and two patients opted for conservative management. OUTCOMES: The main differences between surgically and non-surgically treated cases are the presence of autophony and pressure-induced vertigo and a more severe experience of symptoms in surgically treated cases. Surgically treated cases achieved a sizeable reduction in postoperative air-bone gap and resolution of vestibular symptoms. CONCLUSION: The subjective severity of symptoms in combination with shared decision-making is key in determining the appropriate treatment plan for SCDS and concomitant otosclerosis.
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Otosclerose , Deiscência do Canal Semicircular , Cirurgia do Estribo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomada de Decisão Clínica , Otosclerose/cirurgia , Otosclerose/complicações , Deiscência do Canal Semicircular/complicações , Deiscência do Canal Semicircular/cirurgia , Canais Semicirculares/cirurgia , Cirurgia do Estribo/métodosRESUMO
For decades, it was unknown how electron-bifurcating systems in nature prevented energy-wasting short-circuiting reactions that have large driving forces, so synthetic electron-bifurcating molecular machines could not be designed and built. The underpinning free-energy landscapes for electron bifurcation were also enigmatic. We predict that a simple and universal free-energy landscape enables electron bifurcation, and we show that it enables high-efficiency bifurcation with limited short-circuiting (the EB scheme). The landscape relies on steep free-energy slopes in the two redox branches to insulate against short-circuiting using an electron occupancy blockade effect, without relying on nuanced changes in the microscopic rate constants for the short-circuiting reactions. The EB scheme thus unifies a body of observations on biological catalysis and energy conversion, and the scheme provides a blueprint to guide future campaigns to establish synthetic electron bifurcation machines.
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BACKGROUND: Ultrasound examination of the salivary glands (SG) is a quick and noninvasive method to detect and semiquantitatively estimate typical changes in the large SG in Sjögren's syndrome (SS). The differential diagnosis of SS is difficult because several diseases and adverse effects of treatment have a similar clinical picture as SS with sicca syndrome and can even induce alterations in the SG (mimic diseases). Hence, for a long time an SG biopsy was regarded as the diagnostic procedure of choice, especially in SSA negative patients, whereas the significance of SD sonography is still controversially discussed. OBJECTIVE: Comparison of typical and atypical changes for SS in the salivary glands in ultrasound and associated histological sections. MATERIAL AND METHODS: This article describes six patient cases with antibody positive or negative SS with and without typical SS ultrasound patterns, SS-associated lymphoma, sarcoidosis and IgG4-associated disease. The findings of the sonographic examination of the parotid glands and the associated histology of the SD are explained and put into context. RESULTS: The SSA antibody positive patients with SS show a typical sonographic pattern with hypoechoic foci, especially if the disease has been present for a long time. This pattern can help support the diagnosis of SS. The ultrasound patterns of the mimic diseases sometimes differ significantly from the typical patterns of pSS. The histological examination of the SG helps to corroborate the diagnosis but low histological focus scores, in particular, require a critical synopsis of the clinical, serological and imaging findings. CONCLUSION: Both salivary gland ultrasound and the histological examination of SG biopsies are justified in the diagnostics and differential diagnosis of SS and sicca syndrome.
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Síndrome de Sjogren , Humanos , Síndrome de Sjogren/diagnóstico por imagem , Glândulas Salivares/diagnóstico por imagem , Glândulas Salivares/patologia , Glândula Parótida , Ultrassonografia , BiópsiaRESUMO
Gambling disorder (GD) is a behavioral addiction associated with impairments in value-based decision-making and behavioral flexibility and might be linked to changes in the dopamine system. Maximizing long-term rewards requires a flexible trade-off between the exploitation of known options and the exploration of novel options for information gain. This exploration-exploitation trade-off is thought to depend on dopamine neurotransmission. We hypothesized that human gamblers would show a reduction in directed (uncertainty-based) exploration, accompanied by changes in brain activity in a fronto-parietal exploration-related network. Twenty-three frequent, non-treatment seeking gamblers and twenty-three healthy matched controls (all male) performed a four-armed bandit task during functional magnetic resonance imaging (fMRI). Computational modeling using hierarchical Bayesian parameter estimation revealed signatures of directed exploration, random exploration, and perseveration in both groups. Gamblers showed a reduction in directed exploration, whereas random exploration and perseveration were similar between groups. Neuroimaging revealed no evidence for group differences in neural representations of basic task variables (expected value, prediction errors). Our hypothesis of reduced frontal pole (FP) recruitment in gamblers was not supported. Exploratory analyses showed that during directed exploration, gamblers showed reduced parietal cortex and substantia-nigra/ventral-tegmental-area activity. Cross-validated classification analyses revealed that connectivity in an exploration-related network was predictive of group status, suggesting that connectivity patterns might be more predictive of problem gambling than univariate effects. Findings reveal specific reductions of strategic exploration in gamblers that might be linked to altered processing in a fronto-parietal network and/or changes in dopamine neurotransmission implicated in GD.SIGNIFICANCE STATEMENT Wiehler et al. (2021) report that gamblers rely less on the strategic exploration of unknown, but potentially better rewards during reward learning. This is reflected in a related network of brain activity. Parameters of this network can be used to predict the presence of problem gambling behavior in participants.
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Comportamento Aditivo/fisiopatologia , Encéfalo/fisiopatologia , Jogo de Azar/fisiopatologia , Aprendizagem/fisiologia , Reforço Psicológico , Adulto , Comportamento de Escolha/fisiologia , Simulação por Computador , Humanos , Imageamento por Ressonância Magnética , Masculino , RecompensaRESUMO
Adapted fixation methods for electron microscopy allowed us to study liver cell fine structure in 217 biopsies of intact human livers over the course of 10 years. The following novel observations and concepts arose: single fat droplets in parenchymal cells can grow to a volume four times larger than the original cell, thereby extremely marginalizing the cytoplasm with all organelles. Necrosis of single parenchymal cells, still containing one huge fat droplet, suggests death by fat in a process of single-cell steatonecrosis. In a later stage of single-cell steatonecrosis, neutrophils and erythrocytes surround the single fat droplet, forming an inflammatory fat follicle indicating the apparent onset of inflammation. Also, fat droplets frequently incorporate masses of filamentous fragments and other material, most probably representing Mallory substance. No other structure or material was found that could possibly represent Mallory bodies. We regularly observe the extrusion of huge fat droplets, traversing the peripheral cytoplasm of parenchymal cells, the Disse space and the endothelium. These fat droplets fill the sinusoid as a sinusoidal lipid embolus. In conclusion, adapted methods of fixation applied to human liver tissue revealed that single, huge fat droplets cause necrosis and inflammation in single parenchymal cells. Fat droplets also collect Mallory substance and give rise to sinusoidal fat emboli. Therefore, degreasing of the liver seems to be an essential therapeutic first step in the self-repairing of non-alcoholic fatty liver disease. This might directly reduce single-cell steatotic necrosis and inflammation as elements in non-alcoholic steatohepatitis progression.
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Fígado , Hepatopatia Gordurosa não Alcoólica , Hepatócitos/patologia , Humanos , Inflamação/metabolismo , Fígado/patologia , Necrose/metabolismo , Necrose/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismoRESUMO
PURPOSE: Evidence from cross-sectional studies suggests that higher levels of light-intensity physical activity (LPA) are associated with better health-related quality of life (HRQoL) in colorectal cancer (CRC) survivors. However, these associations have not been investigated in longitudinal studies that provide the opportunity to analyse how within-individual changes in LPA affect HRQoL. We investigated longitudinal associations of LPA with HRQoL outcomes in CRC survivors, from 6 weeks to 2 years post-treatment. METHODS: Data were used of a prospective cohort study among 325 stage I-III CRC survivors (67% men, mean age: 67 years), recruited between 2012 and 2016. Validated questionnaires were used to assess hours/week of LPA (SQUASH) and HRQoL outcomes (EORTC QLQ-C30, Checklist Individual Strength) at 6 weeks, and 6, 12 and 24 months post-treatment. We applied linear mixed regression to analyse longitudinal confounder-adjusted associations of LPA with HRQoL. RESULTS: We observed statistically significant longitudinal associations between more LPA and better global quality of life and physical, role and social functioning, and less fatigue over time. Intra-individual analysis showed that within-person increases in LPA (per 8 h/week) were related to improved HRQoL, including better global quality of life (ß = 1.67, 95% CI 0.71; 2.63; total range scale: 0-100) and less fatigue (ß = - 1.22, 95% CI - 2.37; - 0.07; scale: 20-140). Stratified analyses indicated stronger associations among participants below the median of moderate-to-vigorous physical activity (MVPA) at diagnosis. CONCLUSION: Higher levels of LPA were longitudinally associated with better HRQoL and less fatigue in CRC survivors up to two years post-treatment. Further prospective studies using accelerometer data are necessary to inform development of interventions targeting LPA.
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Exercício Físico/fisiologia , Fadiga/etiologia , Qualidade de Vida/psicologia , Idoso , Neoplasias do Colo , Neoplasias Colorretais/complicações , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos ProspectivosRESUMO
Gastrointestinal conditions in which the transit of contents is altered may benefit from nutritional approaches to influencing health outcomes. Milk proteins modulate the transit of contents along different regions, suggesting that they have varying effects on neuromuscular function to alter gastrointestinal motility. We tested the hypothesis that bovine whey and casein milk protein hydrolysates could have direct modulatory effects on colonic motility patterns in isolated rat large intestine. Casein protein hydrolysate (CPH), whey protein concentrate (WPC), whey protein hydrolysate (WPH), and a milk protein hydrolysate (MPH; a hydrolyzed blend of 60% whey to 40% casein) were compared for their effects on spontaneous contractile waves. These contractions propagate along the length of the isolated intact large intestine (22 cm) between the proximal colon and rectum and were detected by measuring activity at 4 locations. Milk proteins were perfused through the tissue bath, and differences in contraction amplitude and frequency were quantified relative to pretreatment controls. Propagation frequency was decreased by CPH, increased by MPH, and unaffected by intact whey proteins. The reduced motility with CPH and increased motility with MPH indicate a direct action of these milk proteins on colon tissue and provide evidence for differential modulation by hydrolysate type. These findings mirror actions on lower gastrointestinal transit reported in vivo, with the exception of WPH, suggesting that other factors are required.
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Caseínas/farmacologia , Colo/efeitos dos fármacos , Trânsito Gastrointestinal , Contração Muscular/efeitos dos fármacos , Proteínas do Soro do Leite/farmacologia , Animais , Bovinos , Intestino Grosso , Masculino , Hidrolisados de Proteína/farmacologia , Ratos , Ratos Sprague-Dawley , ReproduçãoRESUMO
BACKGROUND: Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a worldwide prevalence of 1-2%. In low-resource environments, in particular, early identification and diagnosis is a significant challenge. Therefore, there is a great demand for 'language-free, culturally fair' low-cost screening tools for ASD that do not require highly trained professionals. Electroencephalography (EEG) has seen growing interest as an investigational tool for biomarker development in ASD and neurodevelopmental disorders. One of the key challenges is the identification of appropriate multivariate, next-generation analytical methodologies that can characterise the complex, nonlinear dynamics of neural networks in the brain, mindful of technical and demographic confounders that may influence biomarker findings. The aim of this study was to evaluate the robustness of recurrence quantification analysis (RQA) as a potential biomarker for ASD using a systematic methodological exploration of a range of potential technical and demographic confounders. METHODS: RQA feature extraction was performed on continuous 5-second segments of resting state EEG (rsEEG) data and linear and nonlinear classifiers were tested. Data analysis progressed from a full sample of 16 ASD and 46 typically developing (TD) individuals (age 0-18 years, 4802 EEG segments), to a subsample of 16 ASD and 19 TD children (age 0-6 years, 1874 segments), to an age-matched sample of 7 ASD and 7 TD children (age 2-6 years, 666 segments) to prevent sample bias and to avoid misinterpretation of the classification results attributable to technical and demographic confounders. A clinical scenario of diagnosing an unseen subject was simulated using a leave-one-subject-out classification approach. RESULTS: In the age-matched sample, leave-one-subject-out classification with a nonlinear support vector machine classifier showed 92.9% accuracy, 100% sensitivity and 85.7% specificity in differentiating ASD from TD. Age, sex, intellectual ability and the number of training and test segments per group were identified as possible demographic and technical confounders. Consistent repeatability, i.e. the correct identification of all segments per subject, was found to be a challenge. CONCLUSIONS: RQA of rsEEG was an accurate classifier of ASD in an age-matched sample, suggesting the potential of this approach for global screening in ASD. However, this study also showed experimentally how a range of technical challenges and demographic confounders can skew results, and highlights the importance of probing for these in future studies. We recommend validation of this methodology in a large and well-matched sample of infants and children, preferably in a low- and middle-income setting.
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Transtorno do Espectro Autista/diagnóstico por imagem , Biomarcadores/química , Eletroencefalografia/métodos , Adolescente , Transtorno do Espectro Autista/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , MasculinoRESUMO
Systemic inflammation is accompanied by profound behavioral and mood changes that resemble symptoms of depression. Findings in animals suggest that pro-inflammatory cytokines released by activated immune cells in the periphery evoke these behavioral symptoms by driving inflammatory changes in the brain. However, experimental data in humans are lacking. Here we demonstrate in healthy male volunteers (10 endotoxin treated, 8 placebo treated) that intravenous administration of low-dose endotoxin (0.8 ng/kg body weight), a prototypical pathogen-associated molecular pattern that activates the innate immune system, not only induces a significant increase in peripheral blood cytokine concentrations (that is, tumor necrosis factor-α, interleukin (IL)-6, IL-10) but also results, with some latency, in a robust and selective increase of IL-6 in the cerebrospinal fluid (CSF). Moreover, we found a strong association between the endotoxin-induced increase of IL-6 in the CSF and the severity of mood impairment, with larger increases in CSF IL-6 concentration followed by a greater deterioration in mood. Taken together, these findings suggest that the appearance of depressive symptoms in inflammatory conditions might be primarily linked to an increase in central IL-6 concentration, identifying IL-6 as a potential therapeutic target in mood disorders.
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Depressão/imunologia , Endotoxinas/administração & dosagem , Inflamação/imunologia , Interleucina-6/líquido cefalorraquidiano , Adulto , Citocinas/sangue , Depressão/sangue , Depressão/líquido cefalorraquidiano , Depressão/metabolismo , Humanos , Imunidade Inata , Inflamação/sangue , Inflamação/líquido cefalorraquidiano , Inflamação/psicologia , Interleucina-6/imunologia , Masculino , Adulto JovemRESUMO
Rapid detection of bacteria responsible for foodborne diseases is a growing necessity for public health. Reporter bacteriophages (phages) are robust biorecognition elements uniquely suited for the rapid and sensitive detection of bacterial species. The advantages of phages include their host specificity, ability to distinguish viable and non-viable cells, low cost, and ease of genetic engineering. Upon infection with reporter phages, target bacteria express reporter enzymes encoded within the phage genome. In this study, the T7 coliphage was genetically engineered to express the newly developed luceriferase, NanoLuc (NLuc), as an indicator of bacterial contamination. While several genetic approaches were employed to optimize reporter enzyme expression, the novel achievement of this work was the successful fusion of the NanoLuc reporter to a carbohydrate binding module (CBM) with specificity to crystalline cellulose. This novel chimeric reporter (nluc::cbm) bestows the specific and irreversible immobilization of NanoLuc onto a low-cost, widely available crystalline cellulosic substrate. We have shown the possibility of detecting the immobilized fusion protein in a filter plate which resulted from a single CFU of E. coli. We then demonstrated that microcrystalline cellulose can be used to concentrate the fusion reporter from 100 mL water samples allowing a limit of detection of <10 CFU mL-1E. coli in 3 hours. Therefore, we conclude that our phage-based detection assay displays significant aptitude as a proof-of-concept drinking water diagnostic assay for the low-cost, rapid and sensitive detection of E. coli. Additional improvements in the capture efficiency of the phage-based fusion reporter should allow a limit of detection of <10 CFU per 100 mL.
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Bacteriófago T7 , Água Potável/microbiologia , Escherichia coli/isolamento & purificação , Engenharia Genética , Limite de Detecção , Estudo de Prova de Conceito , Microbiologia da ÁguaRESUMO
OBJECTIVE: Our goal was to develop a tele-colposcopy platform for primary-care clinics to improve screening sensitivity and access. Specifically, we developed a low-cost, portable Pocket colposcope and evaluated its performance in a tertiary healthcare centre in Peru. DESIGN AND SETTING: Images of the cervix were captured with a standard-of-care and Pocket colposcope at la Liga Contra el Cáncer in Lima, Peru. POPULATION: Two hundred Peruvian women with abnormal cytology and/or human papillomavirus positivity were enrolled. METHODS: Images were collected using acetic acid and Lugol's iodine as contrast agents. Biopsies were taken as per standard-of-care procedures. MAIN OUTCOME MEASURES: After passing quality review, images from 129 women were sent to four physicians who provided a diagnosis for each image. RESULTS: Physician interpretation of images from the two colposcopes agreed 83.1% of the time. The average sensitivity and specificity of physician interpretation compared with pathology was similar for the Pocket (sensitivity = 71.2%, specificity = 57.5%) and standard-of-care (sensitivity = 79.8%, specificity = 56.6%) colposcopes. When compared with a previous study where only acetic acid was applied to the cervix, results indicated that adding Lugol's iodine as a secondary contrast agent improved the percent agreement between colposcopes for all pathological categories by up to 8.9% and the sensitivity and specificity of physician interpretation compared with pathology by over 6.0 and 9.0%, respectively. CONCLUSIONS: The Pocket colposcope performance was similar to that of a standard-of-care colposcope when used to identify precancerous and cancerous lesions using acetic acid and Lugol's iodine during colposcopy examinations in Peru. TWEETABLE ABSTRACT: The Pocket colposcope performance was similar to that of a standard-of-care colposcope when identifying cervical lesions.
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Ácido Acético/farmacologia , Colposcópios , Colposcopia , Detecção Precoce de Câncer/métodos , Iodetos/farmacologia , Doenças do Colo do Útero/diagnóstico , Adulto , Biópsia/métodos , Colposcopia/instrumentação , Colposcopia/métodos , Meios de Contraste/farmacologia , Desenho de Equipamento , Feminino , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Peru/epidemiologia , Sistemas Automatizados de Assistência Junto ao Leito , Atenção Primária à Saúde/métodos , Doenças do Colo do Útero/classificação , Doenças do Colo do Útero/epidemiologiaRESUMO
Pure phospholipids and membrane fragments from bacterial cells living under various conditions were studied against the influence of the surrounding acidity on the internal dynamics. For that we compared mean square displacements extracted from elastic incoherent neutron scattering data, measured both at low and at neutral pH, of the phospholipids 1,2-dimyristoyl-sn-glycero-3-phosphocholine and of samples from neutralophilic and acidophilic micro-organisms (some being hyperthermophilic and others mesophilic). The lipids showed a slight shift in the phase transition temperature of about 4 degrees under pH variation and became slightly more mobile at lower pH. The membrane fragments not used to extreme acidic conditions were significantly more sensitive to variations in the pH values, whereas the acidophilic and -tolerant samples were much less influenced by this parameter. They presented the higher softness at low pH, which was closer to their native condition. Such findings might be a hint for adaptation mechanisms to different acidity conditions.
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Membrana Celular/química , Simulação de Dinâmica Molecular , Acidithiobacillus/química , Acidithiobacillus/fisiologia , Elasticidade , Escherichia coli/química , Escherichia coli/fisiologia , Concentração de Íons de Hidrogênio , Fosfolipídeos/química , Wolinella/química , Wolinella/fisiologiaRESUMO
BACKGROUND: Clinical risk factors for postoperative nausea and vomiting (PONV) are evaluated with the Apfel score, however patients with low Apfel scores still experience PONV suggesting a genetic predisposition. PONV risk associates with specific M3 muscarinic acetylcholine receptor (CHRM3) rs 2165870 polymorphism. We investigated whether the Apfel score and this genetic variation independently contribute to PONV risk and whether prophylaxis reduces PONV in patients with low Apfel score but at high genetic risk. METHODS: In a prospective, controlled study, 454 subjects undergoing elective surgery were genotyped for rs2165870 and its association with PONV was investigated with log-binomial regression analysis. Subjects were randomised to receive acustimulation/dexamethasone, acustimulation/vehicle, sham acustimulation/dexamethasone, or sham acustimulation/vehicle to investigate their effects on PONV risk. RESULTS: Early PONV occurred in 37% of subjects. The rs2165870 genotype distribution was GG in 191, GA in 207, and AA in 56 subjects. The CHRM3 polymorphism was associated with a relative risk (RR) of 1.5 for GA vs GG [95% confidence interval (CI): 1.1-1.9; P=0.003] and 1.6 for AA vs GG (95% CI: 1.1-2.2; P=0.009) genotypes to develop PONV, and this was independent from the Apfel score (RR per Apfel point: 1.3, 95% CI: 1.2-1.5; P<0.0001). While dexamethasone and acustimulation each reduced the PONV risk by 30% in AA genotype carriers with low Apfel score, combined therapy reduced the risk by 86% (P=0.015). CONCLUSIONS: The CHRM3 polymorphism and the Apfel score independently predict PONV susceptibility. Dexamethasone/acustimulation should be considered in patients with low Apfel score but at high genetic risk. CLINICAL TRIAL REGISTRATION: DRKS00005664.
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Polimorfismo Genético/genética , Náusea e Vômito Pós-Operatórios/epidemiologia , Náusea e Vômito Pós-Operatórios/genética , Receptor Muscarínico M3/genética , Terapia por Acupuntura , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral , Antieméticos , Terapia Combinada , Dexametasona , Procedimentos Cirúrgicos Eletivos , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Náusea e Vômito Pós-Operatórios/prevenção & controle , Valor Preditivo dos Testes , Estudos Prospectivos , Risco , Adulto JovemRESUMO
This work addresses the use of the Gaussian approximation as a common tool to extract atomic motions in proteins from elastic incoherent neutron scattering and whether improvements in data analysis and additional information can be obtained when going beyond that. We measured alpha-lactalbumin with different levels of hydration on three neutron backscattering spectrometers, to be able to resolve a wide temporal and spatial range for dynamics. We demonstrate that the Gaussian approximation gives qualitatively similar results to models that include heterogeneity, if one respects a certain procedure to treat the intercept of the elastic intensities with the momentum transfer axis. However, the inclusion of motional heterogeneity provides better fits to the data. Our analysis suggests an approach of limited heterogeneity, where including only two kinds of motions appears sufficient to obtain more quantitative results for the mean square displacement. Finally, we note that traditional backscattering spectrometers pose a limit on the lowest accessible momentum transfer. We therefore suggest that complementary information about the spatial evolution of the elastic intensity close to zero momentum transfer can be obtained using other neutron methods, in particular, neutron spin-echo together with polarization analysis.
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AIM: Wound dehiscence is a serious postoperative complication associated both with high morbidity and mortality. It has a significant rate of occurrence in breast reconstruction surgeries with a deep internal epigastric perforator (DIEP) and with a profunda artery perforator (PAP) flap. Risk factors for wound dehiscence include smoking, diabetes mellitus, chronic obstructive pulmonary disease, and obesity. The aim of this pilot study was to assess whether postoperative treatment with closed incision negative pressure therapy (ciNPT) decreases the incidence of donor site wound dehiscence in breast reconstruction patients. METHOD: Women undergoing a breast reconstruction with a DIEP or PAP flap were enrolled in a pilot randomized controlled trial and assigned treatment with either ciNPT or adhesive strips. The primary outcome was wound dehiscence upon follow-up after four weeks. Secondary outcomes that were evaluated included wound infection, pain, and allergy. There was no loss to follow-up. RESULTS: This pilot study included 51 women (nâ¯=â¯25 ciNPT, nâ¯=â¯26 adhesive strips). The two groups did not differ significantly in patients demographics or comorbidities. Wound dehiscence occurred in 11 patients (nâ¯=â¯2 ciNPT, nâ¯=â¯9 adhesive strips). This difference was statistically significant: pâ¯=â¯0.038. There were no statistically significant differences in secondary outcomes between the two groups. CONCLUSION: In this pilot study, postoperative treatment with ciNPT decreased the incidence of donor site wound dehiscence in breast reconstruction patients. Further research is ongoing by the same hospital. This trial was registered in the Netherlands Trial Register (NTR) under ID no. NTR5808.
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Tratamento de Ferimentos com Pressão Negativa/normas , Deiscência da Ferida Operatória/terapia , Adulto , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Tratamento de Ferimentos com Pressão Negativa/métodos , Projetos Piloto , Complicações Pós-Operatórias/terapia , Estudos Prospectivos , Procedimentos de Cirurgia Plástica/métodos , Procedimentos de Cirurgia Plástica/normas , Fatores de Risco , Método Simples-Cego , Retalhos Cirúrgicos/normas , Retalhos Cirúrgicos/cirurgia , Infecção da Ferida Cirúrgica/cirurgia , Infecção da Ferida Cirúrgica/terapiaRESUMO
AIMS: To characterize the prevalence of Type 2 diabetes between 1991 and 2013 in the UK and to determine whether corresponding glucose control and survival had changed in the diabetic population during this period. METHODS: For this retrospective cohort study, people diagnosed with Type 2 diabetes between 1991 and 2013 were identified from the Clinical Practice Research Datalink (CPRD) and the annual point prevalence calculated. Mean HbA1c by year was estimated. The Cox proportional hazards model was used to calculate the risk of all-cause mortality by year for incident cases of Type 2 diabetes treated with glucose-lowering therapy. RESULTS: Crude prevalence of diagnosed Type 2 diabetes increased from 1.32% [95% confidence interval (95% CI) 1.30% to 1.34%] in 1991 to 4.54% (4.52% to 4.56%) in 2013. Mean HbA1c for people with diagnosed Type 2 diabetes was 71 mmol/mol (8.6%) in 1991, 59 mmol/mol (7.5%) in 2003 and 58 mmol/mol (7.5%) in 2013. For diagnosed Type 2 diabetes treated with glucose-lowering therapy, when compared with 1991, the hazard ratio for all-cause mortality was 0.33 (0.27-0.41) in 2013. CONCLUSION: The prevalence of diagnosed Type 2 diabetes trebled in the UK between 1991 and 2013. Improved survival in people with diagnosed Type 2 diabetes is likely to account, at least in part, for the increase in prevalence observed.
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Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobinas Glicadas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Diabetes Mellitus Tipo 2/mortalidade , Diabetes Mellitus Tipo 2/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Análise de Sobrevida , Reino Unido/epidemiologiaRESUMO
Human low-density lipoprotein (LDL) is a highly complex nano-particle built up of various lipid classes and a single large protein moiety (apoB-100) owning essential physiological functions in the human body. Besides its vital role as a supplier of cholesterol and fat for peripheral tissues and cells, it is also a known key player in the formation of atherosclerosis. Due to these important roles in physiology and pathology the elucidation of structural and dynamical details is of great interest. In the current study we drew a broader picture of LDL dynamics using elastic incoherent neutron scattering (EINS) as a function of specified temperature and pressure points. We not only investigated a normolipidemic LDL sample, but also a triglyceride-rich and an oxidized one to mimic pathologic conditions as found under hyperlipidemic conditions or in atherosclerotic plaques, respectively. We could show that pressure has a significant effect on atomic motions in modified forms of LDL, whereas the normolipidemic sample seems to cope much better with high-pressure conditions irrespective of temperature. These findings might be explained by the altered lipid composition, which is either caused through elevated triglyceride content or modifications through lipid peroxidation.
Assuntos
Elasticidade , Lipoproteínas LDL/química , Difração de Nêutrons , Humanos , Pressão Hidrostática , Lipoproteínas LDL/sangueRESUMO
We studied the effects of temperature and hydrostatic pressure on the dynamical properties and folding stability of highly concentrated lysozyme solutions in the absence and presence of the osmolytes trimethylamine-N-oxide (TMAO) and urea. Elastic incoherent neutron scattering (EINS) was applied to determine the mean-squared displacement (MSD) of the protein's hydrogen atoms to yield insights into the effects of these cosolvents on the averaged sub-nanosecond dynamics in the pressure range from ambient up to 4000 bar. To evaluate the additional effect of self-crowding, two protein concentrations (80 and 160 mg mL-1) were used. We observed a distinct effect of TMAO on the internal hydrogen dynamics, namely a reduced mobility. Urea, on the other hand, revealed no marked effect and consequently, no counteracting effect in an urea-TMAO mixture was observed. Different from the less concentrated protein solution, no significant effect of pressure on the MSD was observed for 160 mg mL-1 lysozyme. The EINS experiments were complemented by Fourier-transform infrared (FTIR) spectroscopy measurements, which led to additional insights into the folding stability of lysozyme under the various environmental conditions. We observed a stabilization of the protein in the presence of the compatible osmolyte TMAO and a destabilization in the presence of urea against temperature and pressure for both protein concentrations. Additionally, we noticed a slight destabilizing effect upon self-crowding at very high protein concentration (160 mg mL-1), which is attributable to transient destabilizing intermolecular interactions. Furthermore, a pressure-temperature diagram could be obtained for lysozyme at these high protein concentrations that mimics densely packed intracellular conditions.
Assuntos
Muramidase/química , Dobramento de Proteína , Temperatura , Hidrogênio , Metilaminas , Difração de Nêutrons , Ureia/química , Água/químicaRESUMO
An essential role of enzymes is to catalyze various chemical reactions in the human body and inhibition of the enzymatic activity by small molecules is the mechanism of action of many drugs or tool compounds used to study biological processes. Here, we investigate the effect on the dynamics of the serine protease α-chymotrypsin when in complex with two different covalently bound inhibitors using elastic incoherent neutron scattering. The results show that the inhibited enzyme displays enhanced dynamics compared to the free form. The difference was prominent at higher temperatures (240-310 K) and the type of motions that differ include both small amplitude motions, such as hydrogen atom rotations around a methyl group, and large amplitude motions, such as amino acid side chain movements. The measurements were analyzed with multivariate methods in addition to the standard univariate methods, allowing for a more in-depth analysis of the types of motions that differ between the two forms. The binding strength of an inhibitor is linked to the changes in dynamics occurring during the inhibitor-enzyme binding event and thus these results may aid in the deconvolution of this fundamental event and in the design of new inhibitors.