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1.
OTO Open ; 8(3): e137, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015736

RESUMO

Objective: To evaluate the readability, understandability, actionability, and accuracy of online resources covering vestibular migraine (VM). Study Design: Cross-sectional descriptive study design. Setting: Digital collection of websites appearing on Google search. Methods: Google searches were conducted to identify common online resources for VM. We examined readability using the Flesch Reading Ease (FRE) and Flesch-Kincaid Grade Level scores, understandability and actionability using the Patient Education Materials Assessment Tool (PEMAT), and accuracy by comparing the website contents to the consensus definition of "probable vestibular migraine." Results: Eleven of the most popular websites were analyzed. Flesch-Kincaid Grade Level averaged at a 13th-grade level (range: 9th-18th). FRE scores averaged 35.5 (range: 9.1-54.4). No website had a readability grade level at the US Agency for Healthcare Research and Quality recommended 5th-grade level or an equivalent FRE score of 90 or greater. Understandability scores varied ranging from 49% to 88% (mean 70%). Actionability scores varied more, ranging from 12% to 87% (mean 44%). There was substantial inter-rater agreement for both PEMAT understandability scoring (mean κ = 0.76, SD = 0.08) and actionability scoring (mean κ = 0.65, SD = 0.08). Three sites included all 3 "probable vestibular migraine" diagnostic criteria as worded in the consensus statement. Conclusion: The quality of online resources for VM is poor overall in terms of readability, actionability, and agreement with diagnostic criteria.

2.
JMIR Pediatr Parent ; 6: e48924, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38100579

RESUMO

Background: Adolescents and young adults with sickle cell disease (SCD) transitioning from pediatric to adult health care face a high-risk period associated with increased use of acute health care services and mortality. Although 59% of American citizens report using the internet for health care information, the quality of web-based, patient-facing resources regarding transition in SCD care has not been evaluated. Objective: This study aimed to evaluate the quality and readability of web-based health information on SCD, especially as it pertains to the transition to adulthood for inidividuals with SCD. The study also compared the readability and content scores of websites identified in 2018 to those from 2021 to assess any change in quality over time. Methods: Keywords representing phrases adolescents may use while searching for information on the internet regarding transition in SCD care, including "hydroxyurea" and "SCD transition," were identified. A web-based search using the keywords was conducted in July 2021 using Google, Yahoo, and Bing. The top 20 links from each search were collected. Duplicate websites, academic journals, and websites not related to SCD health care transition were excluded. Websites were categorized based on the source: health department, hospital or private clinician, professional society, and other websites. Websites were assessed using Health On the Net Foundation code of conduct (HONcode), Flesch Reading Ease (FRE), Flesch-Kincaid Grade Level (FGL), Ensuring Quality Information for Patients (EQIP), and a novel SCD content checklist (SCDCC). EQIP and SCDCC scores range from 0- to 100. Each website was reviewed by 2 research assistants and assessed for interrater reliability. Descriptive statistics were calculated. Results: Of the 900 websites collected, 67 (7.4%) met the inclusion criteria: 13 health department, 7 hospital or private clinician, 33 professional society, and 14 other websites. A total of 15 (22%) out of 67 websites had HONcode certification. Websites with HONcode certification had higher FRE and EQIP scores and lower FGL scores than those without HONcode certification, reflecting greater readability. Websites without HONcode certification had higher SCDCC scores, reflecting greater clinical content. Only 7 (10%) websites met the National Institutes of Health recommendation of a seventh-grade or lower reading level. Based on EQIP scores, 6 (9%) websites were of high quality. The mean SCDCC score was 20.60 (SD 22.14) out of 100. The interrater reliability for EQIP and SCDCC ratings was good (intraclass correlation: 0.718 and 0.897, respectively). No source of website scored significantly higher mean EQIP, FRE, FGL, or SCDCC scores than the others (all P<.05). Conclusions: Although seeking health care information on the web is very common, the overall quality of information about transition in SCD care on the internet is poor. Changes to current web-based health care information regarding SCD care transitions would benefit transitioning youth by providing expectations, knowledge, skills, and tools to increase self-efficacy.

3.
Mycorrhiza ; 33(3): 139-152, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37165145

RESUMO

Current literature suggests ecological niche differentiation between co-occurring Mucoromycotinian arbuscular mycorrhizal fungi (M-AMF) and Glomeromycotinian AMF (G-AMF), but experimental evidence is limited. We investigated the influence of soil age, water availability (wet and dry), and plant species (native Microlaena stipoides and exotic Trifolium subterraneum) on anatomical root colonisation and DNA profiles of M-AMF and G-AMF under glasshouse conditions. We grew seedlings of each species in soils collected from the four stages of a soil chronosequence, where pH decreases from the youngest to oldest stages, and phosphorus (P) is low in the youngest and oldest, but high in the intermediate stages. We scored the percentage of root length colonised and used DNA metabarcoding to profile fungal richness and community composition associated with treatment combinations. Soil age, water availability, and plant species were important influencers of root colonisation, although no M-AMF were visible following staining of M. stipoides roots. Soil age and host plant influenced fungal richness and community composition. However, response to soil age, potential host species, and water availability differed between M-AMF and G-AMF. Root colonisation of T. subterraneum by M-AMF and G-AMF was inversely correlated with soil P level. Community composition of M-AMF and G-AMF was structured by soil age and, to a lesser extent, plant species. Richness of M-AMF and G-AMF was negatively, and positively, correlated with available P, respectively. These findings are experimental evidence of ecological niche differentiation of M-AMF and G-AMF and invite further exploration into interactive effects of abiotic and biotic factors on their communities along successional trajectories.


Assuntos
Micorrizas , Micorrizas/fisiologia , Solo/química , Raízes de Plantas/microbiologia , Ecossistema , Água , Microbiologia do Solo , Fungos/fisiologia
4.
Materials (Basel) ; 15(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36143602

RESUMO

The interfacial interface between fibers and matrix plays a key role for epoxy matrix composites and short recycled randomly arranged fibers. This study used short recycled carbon fiber (RCF) as a filler. Plasma treatment was used for carbon fiber surface treatment. This treatment was performed using radio (RF) and microwave (MW) frequencies at the same pressure and atmosphere. Appropriate chemical modification of the fiber surfaces helps to improve the wettability of the carbon fibers and, at the same time, allows the necessary covalent bonds to form between fibers and the epoxy matrix. The effect of the plasma treatment was analyzed and confirmed by X-ray photoelectron spectroscopy, Raman microscopy, scanning electron microscopy, transmission electron microscopy and wettability measurements. Composite samples filled with recycled carbon fibers with low concentrations (1 wt%, 2.5 wt% and 5 wt%) and high concentrations (20 wt% and 30 wt%) were made from selected treated fibers. The mechanical properties (impact toughness, 3PB) were analyzed on these samples. It was found that the modulus of elasticity and bending stress increase with the increasing content of recycled carbon fibers. A more significant change in impact strength occurred in samples with low concentration.

5.
Explor Res Clin Soc Pharm ; 8: 100179, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36177271

RESUMO

Background: The Saudi Food and Drug Authority (SFDA) requires marketing authorization holders to submit a PIL in both Arabic and English language. However, the readability of imprinted and disseminated Patient information leaflets (PILs) was not assessed extensively in Saudi Arabia. This study aims to assess the readability of PIL of antihypertensive drugs in both Arabic and English languages. Method: This study was a descriptive quantitative analysis conducted in Saudi Arabia in August 2021. PILs of all oral antihypertensive medications in Saudi Arabia were included in the study. The Arabic and English PILs were extracted from the Saudi Drugs Information System (SDI) and pharmaceutical companies' registration documents. The study used Flesch-Kincaid grade level to assess the readability of English and sentence length to assess the Arabic texts. Descriptive analyses were used to assess the readability scores and the mean differences. Results: It was found that almost 88% of English PILs were above recommended readability level compared to 79% of Arabic PILs. About 89% of English PILs of generic and 86% of brand-name medications were above the readability cutoff point compared with 83% of Arabic PILs of generic and 68% of brand-name medications. The means of grade level for readability of PILs for the widely used antihypertensive medications including angiotensin II receptor blockers (ARBs), antiadrenergic, diuretics, Beta-blockers (BBs), calcium channel blockers (CCBs), and combination antihypertensive medications, and CCBs were higher than the recommended readability level (p < 0.05). The highest mean grade level for readability among English PILs was for combinations of antihypertensive agents (9.35 ± 1.38, p 0.01) and among Arabic PILs was for ARBs (6.15 ± 1.62, p < 0.01). Conclusions: The majority of PILs of antihypertensive medications were above the recommended readability level that can be understood by the majority of the public, especially among generic medications and the most widely used antihypertensive medications. The study findings highlight the need of implementing guidelines to improve the readability of information imprinted in PILs and adopt new regulations requiring readability assessment for manufactures before submitting the PILs to the SFDA.

6.
Sensors (Basel) ; 21(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803711

RESUMO

Sensible energy is the primary mode of heat dissipation from combustion in wildland surface fires. However, despite its importance to fire dynamics, smoke transport, and in determining ecological effects, it is not routinely measured. McCaffrey and Heskestad (A robust bidirectional low-velocity probe for flame and fire application. Combustion and Flame 26:125-127, 1976) describe measurements of flame velocity from a bi-directional probe which, when combined with gas temperature measurements, can be used to estimate sensible heat fluxes. In this first field application of bi-directional probes, we describe vertical and horizontal sensible heat fluxes during the RxCADRE experimental surface fires in longleaf pine savanna and open ranges at Eglin Air Force Base, Florida. Flame-front sensible energy is the time-integral of heat flux over a residence time, here defined by the rise in gas temperatures above ambient. Horizontal flow velocities and energies were larger than vertical velocities and energies. Sensible heat flux and energy measurements were coordinated with overhead radiometer measurements from which we estimated fire energy (total energy generated by combustion) under the assumption that 17% of fire energy is radiated. In approximation, horizontal, vertical, and resultant sensible energies averaged 75%, 54%, and 64%, respectively, of fire energy. While promising, measurement challenges remain, including obtaining accurate gas and velocity measurements and capturing three-dimensional flow in the field.

7.
Saudi J Biol Sci ; 28(4): 2109-2122, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33911927

RESUMO

The natural populations of Dactylorhiza hatagirea have been greatly affected due to incessant exploitation. As such, studies on its population attributes together with habitat suitability and environmental factors affecting its distribution are needed to be undertaken for its conservation in nature. Present study aimed at accessing an impact of anthropogenic pressure on population structure and locate suitable habitats for the conservation of this critically endangered orchid. Considerable changes in the phytosociological attributes were observed on account of the changing magnitude and extent of anthropogenic threat in their natural abode. The distribution pattern of species indicated that more than 90% of the populations exhibit substantially aggregated spatial distribution. Maximum Entropy (MaxEnt) distribution modelling algorithm was used to predict suitable habitat and potential area for its cultivation and reintroduction. Twenty-seven occurrence records, nineteen bioclimatic variables, altitude, and slope were used. MaxEnt map output gave the habitat suitability for this species and predicted its distribution in the North-Western Himalayas of India for approximately 616 km2. Jackknifing indicated that maximum temperature of warmest month, annual mean temperature, mean temperature of the driest quarter, and mean temperature of the wettest quarter were the governing factors for its distribution and hence, presented a higher gain with respect to other variables. According to permutation importance, precipitation seasonality and mean temperature of wettest quarter shows the prominent impact on the habitat distribution. Results of AUC (area under curve) were statistically significant (0.940) and the line of predicted omission falls very close to an omission on training samples, validating a better run of the model. Response curves revealed a probable increase in the occurrence of D. hatagirea with an increase in mean temperature of the wettest quarter and maximum temperature of the warmest month contributed more than 50% to predicted habitat suitability. Direct field observations concurrent with predicted habitat suitability and google-earth images represent greater model thresholds for successful inception of the species. Together, the study proposes that the species can be conserved in or near its present-day natural habitats and is equally effective in determining the possible habitats for its cultivation and reintroduction.

8.
Mycorrhiza ; 30(5): 577-587, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32734329

RESUMO

Mycorrhizal fungi are critical components of terrestrial habitats and agroecosystems. Recently, Mucoromycotina fine root endophyte fungi (MucFRE) were found to engage in nutritional mutualism with Lycopodiella inundata, which belongs to one of the earliest vascular plant lineages known to associate with MucFRE. The extent to which this mutualism plays a role in resilient plant populations can only be understood by examining its occurrence rate and phenological patterns. To test for prevalence and seasonality in colonization, we examined 1305 individual L. inundata roots from 275 plants collected during spring and autumn 2019 across 11 semi-natural heathlands in Britain and the Netherlands. We quantified presence/absence of fine root endophyte (FRE) hyphae and vesicles and explored possible relationships between temperature and precipitation in the months immediately before sampling. Fine root endophyte hyphae were dominant in all of the examined heathlands, and every colonized root had FRE in both cortical cells and root hairs. However, we found significant differences in colonization between the two seasons at every site. Overall, 14% of L. inundata roots were colonized in spring (2.4% with vesicles) compared with 86% in autumn (7.6% with vesicles). Colonization levels between populations were also significantly different, correlating with temperature and precipitation, suggesting some local environments may be more conducive to root and related hyphal growth. These marked seasonal differences in host-plant colonization suggest that results about FRE from single time point collections should be carefully interpreted. Our findings are relevant to habitat restoration, species conservation plans, agricultural bio-inoculation treatments, and microbial diversity studies.


Assuntos
Endófitos , Micorrizas , Raízes de Plantas , Plantas , Prevalência , Simbiose
9.
J Hazard Mater ; 388: 121787, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31818658

RESUMO

Dihalophenols such as dichlorophenols (DCPs) are important industrial chemical intermediates, but also persistent pollutants in the environment. Oxidative dehalogenation by microbes is an efficient biological method to degrade halophenols, but the mechanism is unclear yet. Cupriavidus nantongensis X1T was a type strain of genus Cupriavidus, and could degrade 2,4-dichlorophenol of 50 mg/L within 12 h. The degradation rate constant was approximately 84 fold greater than that by Bacillus endophyticus CP1R43, a well-studied 2,4-DCP-degrading bacterial strain. The genes encoding 2,4,6-trichlorophenol monooxygenase (TcpA) and NAD(P)H:FAD reductase (Fre) from strain X1T were cloned and expressed. The expressed TcpA Fre were purified. The molecular docking of TcpA with DCPs and point mutation experiments showed that the degradation activity of TcpA was associated with the length of the hydrogen bond between the substrates and the amino acids in the active pocket. DCPs were degraded via a stepwise oxidative dechlorination in a positive relationship between the oxidation ability and the electron-withdrawing potential of the p-position group. In addition, TcpA has dual dehalogenation and denitration functions. The results demonstrate that either strain X1T or TcpA and Fre can effectively dehalogenate dihalophenols, which can be useful for the treatment of dihalophenols in wastewaters and remediation of DCP-contaminated environments.


Assuntos
Clorofenóis/metabolismo , Cupriavidus/metabolismo , FMN Redutase/metabolismo , Oxigenases de Função Mista/metabolismo , Biodegradação Ambiental , Catálise , Modelos Moleculares
10.
Traffic ; 20(11): 841-850, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31368617

RESUMO

The accumulation of copper in organisms can lead to altered functions of various pathways and become cytotoxic through the generation of reactive oxygen species. In yeast, cytotoxic metals such as Hg+ , Cd2+ and Cu2+ are transported into the lumen of the vacuole through various pumps. Copper ions are initially transported into the cell by the copper transporter Ctr1 at the plasma membrane and sequestered by chaperones and other factors to prevent cellular damage by free cations. Excess copper ions can subsequently be transported into the vacuole lumen by an unknown mechanism. Transport across membranes requires the reduction of Cu2+ to Cu+ . Labile copper ions can interact with membranes to alter fluidity, lateral phase separation and fusion. Here we found that CuCl2 potently inhibited vacuole fusion by blocking SNARE pairing. This was accompanied by the inhibition of V-ATPase H+ pumping. Deletion of the vacuolar reductase Fre6 had no effect on the inhibition of fusion by copper. This suggests that Cu2+ is responsible for the inhibition of vacuole fusion and V-ATPase function. This notion is supported by the differential effects of chelators. The Cu2+ -specific chelator triethylenetetramine rescued fusion, whereas the Cu+ -specific chelator bathocuproine disulfonate had no effect on the inhibited fusion.


Assuntos
Adenosina Trifosfatases/metabolismo , Cobre/metabolismo , Fusão de Membrana/fisiologia , Proteínas SNARE/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Vacúolos/metabolismo , Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Citoplasma/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas de Transporte Vesicular/metabolismo
11.
FEBS Lett ; 593(22): 3228-3238, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31322728

RESUMO

The nonsense-mediated mRNA decay (NMD) pathway regulates mRNAs that aberrantly terminate translation. This includes aberrant mRNAs and functional natural mRNAs. Natural mRNA degradation by NMD is triggered by mRNA features and environmental cues. Saccharomyces cerevisiae encodes multiple proteins with ferric and cupric reductase activity. Here, we examined the regulation by NMD of two mRNAs, FRE1 and FRE2, encoding ferric and cupric reductases in S. cerevisiae. We found that FRE2 mRNAs are regulated by NMD under noninducing conditions and that the FRE2 3'-UTR contributes to the degradation of the mRNAs by NMD. Conversely, FRE1 mRNAs are not regulated by NMD under comparable conditions. These findings suggest that regulation of functionally related mRNAs by NMD can be differential and conditional.


Assuntos
FMN Redutase/química , FMN Redutase/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Regiões 3' não Traduzidas , Cobre/metabolismo , Ferro/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido , RNA Mensageiro/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Estresse Fisiológico
12.
Phys Med Rehabil Clin N Am ; 30(3): 611-619, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31227136

RESUMO

Life expectancy expertise must comply with court-mandated evidentiary standards. A proper opinion should abide by 3 principles; it should be generated by a qualified expert who applies proper methods to appropriate facts. Several common mistakes can make opinions unsuitable for admission into testimony by straying from 1 or more of these 3 principles. Examining life expectancy opinions in light of these principles allows consumers of life expectancy expertise to evaluate the quality of the opinions proffered.


Assuntos
Prova Pericial , Expectativa de Vida , Prova Pericial/legislação & jurisprudência , Humanos
13.
Proteins ; 87(9): 723-729, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30985024

RESUMO

In luminous bacteria NAD(P)H:flavin-oxidoreductases LuxG and Fre, there are homologous enzymes that could provide a luciferase with reduced flavin. Although Fre functions as a housekeeping enzyme, LuxG appears to be a source of reduced flavin for bioluminescence as it is transcribed together with luciferase. This study is aimed at providing the basic conception of Fre and LuxG evolution and revealing the peculiarities of the active site structure resulted from a functional variation within the oxidoreductase family. A phylogenetic analysis has demonstrated that Fre and LuxG oxidoreductases have evolved separately after the gene duplication event, and consequently, they have acquired changes in the conservation of functionally related sites. Namely, different evolutionary rates have been observed at the site responsible for specificity to flavin substrate (Arg 46). Also, Tyr 72 forming a part of a mobile loop involved in FAD binding has been found to be conserved among Fre in contrast to LuxG oxidoreductases. The conservation of different amino acid types in NAD(P)H binding site has been defined for Fre (arginine) and LuxG (proline) oxidoreductases.


Assuntos
Proteínas de Bactérias/química , FMN Redutase/química , Oxirredutases/química , Proteínas de Bactérias/classificação , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Dinitrocresóis/química , Dinitrocresóis/metabolismo , FMN Redutase/classificação , FMN Redutase/metabolismo , Estrutura Molecular , Oxirredutases/classificação , Oxirredutases/metabolismo , Filogenia , Spinacia oleracea/metabolismo
14.
J Agric Food Chem ; 67(8): 2245-2254, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30721044

RESUMO

Chlorpyrifos is one of the most used organophosphorus insecticides. It is commonly degraded to 3,5,6-trichloro-2-pyridinol (TCP), which is water-soluble and toxic. Bacteria can degrade chlorpyrifos and TCP, but the biodegradation mechanism has not been well-characterized. Recently isolated Cupriavidus nantongensis X1T can completely degrade 100 mg/L chlorpyrifos and 20 mg/L TCP with half-lives of 6 and 8 h, respectively. We annotated a complete gene cluster responsible for TCP degradation in recently sequenced strain X1T. Two key genes, tcpA and fre, were cloned from X1T and transferred and expressed in Escherichia coli BL21(DE3). Degradation of TCP by X1T whole cell was compared with that by the enzymes 2,4,6-trichlorophenol monooxygenase and NAD(P)H:flavin reductase expressed and purified from E. coli BL21(DE3). Novel metabolites of TCP were isolated and characterized, indicating stepwise dechlorination of TCP, which was confirmed by TCP disappearance, mass balance, and detection and formation kinetics of chloride ion from TCP.


Assuntos
Proteínas de Bactérias/química , Clorpirifos/metabolismo , Cupriavidus/enzimologia , FMN Redutase/química , Inseticidas/metabolismo , Oxigenases de Função Mista/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Clorpirifos/química , Cupriavidus/química , Cupriavidus/genética , Cupriavidus/metabolismo , FMN Redutase/genética , FMN Redutase/metabolismo , Halogenação , Inseticidas/química , Cinética , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo
15.
Metab Eng ; 46: 43-50, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29477856

RESUMO

The yeast Saccharomyces cerevisiae is widely used as a cell factory for the biotechnological production of various industrial products. During these processes, yeasts meet different kinds of stressors that often cause oxidative stress and thus impair cell growth. Therefore, the development of robust strains is indispensable to improve production, yield and productivity of fermentative processes. Copper plays a key role in the response to oxidative stress, as cofactor of the cytosolic superoxide dismutase (Sod1) and being contained in metallochaperone and metallothioneines with antioxidant properties. In this work, we observed a higher naturally copper internalization in a robust S. cerevisiae strain engineered to produce the antioxidant l-ascorbic acid (L-AA), compared with the wild type strain. Therefore, we investigated the effect of the alteration of copper homeostasis on cellular stress tolerance. CTR1 and FRE1 genes, codifying for a plasma membrane high-affinity copper transporter and for a cell-surface ferric/cupric reductase, respectively, were overexpressed in both wild type and L-AA cells. Remarkably, we found that the sole FRE1 overexpression was sufficient to increase copper internalization leading to an enhanced stress tolerance toward H2O2 exposure, in both strains under investigation. These findings reveal copper homeostasis as a target for the development of robust cell factories.


Assuntos
Cobre/metabolismo , Homeostase , Estresse Oxidativo , Saccharomyces cerevisiae , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Transportador de Cobre 1 , FMN Redutase/genética , FMN Redutase/metabolismo , Peróxido de Hidrogênio , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
17.
J Biol Chem ; 292(6): 2485-2494, 2017 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28028176

RESUMO

MsrPQ is a newly identified methionine sulfoxide reductase system found in bacteria, which appears to be specifically involved in the repair of periplasmic proteins oxidized by hypochlorous acid. It involves two proteins: a periplasmic one, MsrP, previously named YedY, carrying out the Msr activity, and MsrQ, an integral b-type heme membrane-spanning protein, which acts as the specific electron donor to MsrP. MsrQ, previously named YedZ, was mainly characterized by bioinformatics as a member of the FRD superfamily of heme-containing membrane proteins, which include the NADPH oxidase proteins (NOX/DUOX). Here we report a detailed biochemical characterization of the MsrQ protein from Escherichia coli We optimized conditions for the overexpression and membrane solubilization of an MsrQ-GFP fusion and set up a purification scheme allowing the production of pure MsrQ. Combining UV-visible spectroscopy, heme quantification, and site-directed mutagenesis of histidine residues, we demonstrated that MsrQ is able to bind two b-type hemes through the histidine residues conserved between the MsrQ and NOX protein families. In addition, we identify the E. coli flavin reductase Fre, which is related to the dehydrogenase domain of eukaryotic NOX enzymes, as an efficient cytosolic electron donor to the MsrQ heme moieties. Cross-linking experiments as well as surface Plasmon resonance showed that Fre interacts with MsrQ to form a specific complex. Taken together, these data support the identification of the first prokaryotic two-component protein system related to the eukaryotic NOX family and involved in the reduction of periplasmic oxidized proteins.


Assuntos
Escherichia coli/enzimologia , Metionina Sulfóxido Redutases/metabolismo , NADPH Oxidases/metabolismo , Sequência de Aminoácidos , Transporte de Elétrons , Proteínas de Fluorescência Verde/genética , Metionina Sulfóxido Redutases/química , Metionina Sulfóxido Redutases/genética , Mutagênese Sítio-Dirigida , Homologia de Sequência de Aminoácidos , Espectrofotometria Ultravioleta , Ressonância de Plasmônio de Superfície
18.
J Neurosurg ; 126(6): 1924-1933, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27611206

RESUMO

OBJECTIVE Preoperative magnetic resonance images (pMR) are typically coregistered to provide intraoperative navigation, the accuracy of which can be significantly compromised by brain deformation. In this study, the authors generated updated MR images (uMR) in the operating room (OR) to compensate for brain shift due to dural opening, and evaluated the accuracy and computational efficiency of the process. METHODS In 20 open cranial neurosurgical cases, a pair of intraoperative stereovision (iSV) images was acquired after dural opening to reconstruct a 3D profile of the exposed cortical surface. The iSV surface was registered with pMR to detect cortical displacements that were assimilated by a biomechanical model to estimate whole-brain nonrigid deformation and produce uMR in the OR. The uMR views were displayed on a commercial navigation system and compared side by side with the corresponding coregistered pMR. A tracked stylus was used to acquire coordinate locations of features on the cortical surface that served as independent positions for calculating target registration errors (TREs) for the coregistered uMR and pMR image volumes. RESULTS The uMR views were visually more accurate and well aligned with the iSV surface in terms of both geometry and texture compared with pMR where misalignment was evident. The average misfit between model estimates and measured displacements was 1.80 ± 0.35 mm, compared with the average initial misfit of 7.10 ± 2.78 mm between iSV and pMR, and the average TRE was 1.60 ± 0.43 mm across the 20 patients in the uMR image volume, compared with 7.31 ± 2.82 mm on average in the pMR cases. The iSV also proved to be accurate with an average error of 1.20 ± 0.37 mm. The overall computational time required to generate the uMR views was 7-8 minutes. CONCLUSIONS This study compensated for brain deformation caused by intraoperative dural opening using computational model-based assimilation of iSV cortical surface displacements. The uMR proved to be more accurate in terms of model-data misfit and TRE in the 20 patient cases evaluated relative to pMR. The computational time was acceptable (7-8 minutes) and the process caused minimal interruption of surgical workflow.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Humanos , Procedimentos Neurocirúrgicos/métodos , Cirurgia Assistida por Computador/métodos
19.
J Neurosurg ; 126(4): 1263-1268, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27257833

RESUMO

OBJECTIVE Closing the knowledge gap that exists between patients and health care providers is essential and is facilitated by easy access to patient education materials. Although such information has the potential to be an effective resource, it must be written in a user-friendly and understandable manner, especially when such material pertains to specialized and highly technical fields such as neurological surgery. The authors evaluated the accessibility, usability, and reliability of current educational resources provided by the American Association of Neurological Surgeons (AANS), Healthwise, and the National Institute for Neurological Disorders and Stroke (NINDS). METHODS Online neurosurgical patient education information provided by AANS, Healthwise, and NINDS was evaluated using the LIDA scale, a website quality assessment tool, by medical professionals and nonmedical professionals. A high achieving score is regarded as 90% or greater using the LIDA scale. RESULTS Accessibility scores were 76.7% (AANS), 83.3% (Healthwise), and 75.0% (NINDS). Average usability scores for the AANS, Healthwise, and NINDS were 73.3%, 82.6%, and 82.9%, respectively, when evaluated by medical professionals and 78.5%, 80.7%, and 75.9%, respectively, for nonmedical professionals, respectively. Average reliability scores were 58.5%, 53.3%, 72.6%, respectively, for medical professionals and 70.4%, 66.7%, and 78.5%, respectively, for nonmedical professionals when evaluating the AANS, Healthwise, and NINDS websites. CONCLUSIONS Although organizations like AANS, Healthwise, and NINDS should be commended for their ongoing commitment to provide health care-oriented materials, modification of this material is suggested to improve the patient education value.


Assuntos
Neurocirurgia/educação , Educação de Pacientes como Assunto , Garantia da Qualidade dos Cuidados de Saúde , Estudos de Coortes , Pessoal de Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Internet , National Institute of Neurological Disorders and Stroke (USA) , Sociedades Médicas , Estados Unidos
20.
ACS Biomater Sci Eng ; 2(10): 1781-1786, 2016 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-27747289

RESUMO

Polydimethylsiloxane (PDMS) elastomer is used in a wide range of biomaterial applications including microfluidics, cell culture substrates, flexible electronics, and medical devices. However, it has proved challenging to 3D print PDMS in complex structures due to its low elastic modulus and need for support during the printing process. Here we demonstrate the 3D printing of hydrophobic PDMS prepolymer resins within a hydrophilic Carbopol gel support via freeform reversible embedding (FRE). In the FRE printing process, the Carbopol support acts as a Bingham plastic that yields and fluidizes when the syringe tip of the 3D printer moves through it, but acts as a solid for the PDMS extruded within it. This, in combination with the immiscibility of hydrophobic PDMS in the hydrophilic Carbopol, confines the PDMS prepolymer within the support for curing times up to 72 h while maintaining dimensional stability. After printing and curing, the Carbopol support gel releases the embedded PDMS prints by using phosphate buffered saline solution to reduce the Carbopol yield stress. As proof-of-concept, we used Sylgard 184 PDMS to 3D print linear and helical filaments via continuous extrusion and cylindrical and helical tubes via layer-by-layer fabrication. Importantly, we show that the 3D printed tubes were manifold and perfusable. The results demonstrate that hydrophobic polymers with low viscosity and long cure times can be 3D printed using a hydrophilic support, expanding the range of biomaterials that can be used in additive manufacturing. Further, by implementing the technology using low cost open-source hardware and software tools, the FRE printing technique can be rapidly implemented for research applications.

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