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1.
Transl Vis Sci Technol ; 13(4): 27, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38639929

RESUMO

Purpose: To understand the association between anatomical parameters of healthy eyes and optical coherence tomography (OCT) circumpapillary retinal nerve fiber layer (cpRNFL) thickness measurements. Methods: OCT cpRNFL thickness was obtained from 396 healthy eyes in a commercial reference database (RDB). The temporal quadrant (TQ), superior quadrant (SQ), inferior quadrant (IQ), and global (G) cpRNFL thicknesses were analyzed. The commercial OCT devices code these values based on percentiles (red, <1%; yellow, ≥1% and <5%), after taking age and disc area into consideration. Four anatomical parameters were assessed: fovea-to-disc distance, an estimate of axial length, and the locations of the superior and the inferior peaks of the cpRNFL thickness curve. Pearson correlation values were obtained for the parameters and the thickness measures of each of the four cpRNFL regions, and t-tests were performed between the cpRNFL thicknesses coded as abnormal (red or yellow, <5%) versus normal (≥5%). Results: For each of the four anatomical parameters, the correlation with the thickness of one or more of the TQ, SQ, IQ, and G regions exceeded the correlation with age or disc area. All four parameters were significantly (P < 0.001) associated with the abnormal cpRNFL values. The significant parameters were not the same for the different regions; for example, a parameter could be negatively correlated for the TQ but positively correlated with the SQ or IQ. Conclusions: In addition to age and disc area, which are used for inferences in normative databases, four anatomical parameters are associated with cpRNFL thickness. Translational Relevance: Taking these additional anatomical parameters into consideration should aid diagnostic accuracy.


Assuntos
Células Ganglionares da Retina , Tomografia de Coerência Óptica , Fóvea Central , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos , Ensaios Clínicos como Assunto , Humanos
2.
Antiviral Res ; : 105876, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641023

RESUMO

BACKGROUND: HBeAg loss is an important endpoint for antiviral therapy in chronic hepatitis B (CHB), however there are no reliable biomarkers to identify patients who will respond to the addition of pegylated interferon to nucleos(t)ide analogue (NA) therapy. AIM: To evaluate the use of serum biomarkers to predict HBeAg loss. METHODS: HBeAg positive CHB participants on NAs who switched-to or added-on 48 weeks pegylated interferon alpha2b (clinicaltrial.gov NCT01928511) were evaluated at week 72 for HBeAg loss. The predictive ability of qHBeAg, qHBsAg, HBV RNA and clinical variables for HBeAg loss were investigated. RESULTS: HBeAg loss occurred in 15/55 (27.3%) participants who completed 48 weeks of pegylated interferon. There was a lower baseline qHBeAg (1.18 IU/mL [2.27] versus 10.04 IU/mL [24.87], P = 0.007) among participants who lost HBeAg. Baseline qHBeAg (OR = 0.15, 95% CI 0.03-0.66, P = 0.01) and detectable HBV DNA at baseline (OR = 25.00, 95% CI 1.67-374.70, P = 0.02) were independent predictors of HBeAg loss. In addition, on-treatment qHBeAg was also a strong predictor of HBeAg loss (OR = 0.39, 95% CI 0.18-0.81, P = 0.012). The models combining detectable baseline HBV DNA with baseline (C-statistic 0.82) and on-treatment (C-statistic 0.83) had good accuracy for predicting HBeAg loss. A rise in qHBeAg ≥ 10 IU/ml was a predictor of flare (ALT ≥ 120 U/ml) on univariable analysis but not after adjustment for treatment arm. CONCLUSIONS: Baseline and on-treatment qHBeAg is a useful biomarker that can identify participants on NA therapy who may benefit from adding or switching to pegylated interferon.

3.
Patient ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582797

RESUMO

OBJECTIVE: We aimed to identify the health and quality-of-life research priorities of Australians with diabetes or family members. METHODS: Through an iterative, three-step, online survey process we (1) qualitatively generated research topics (long list) in response to one question "What research is needed to support people with diabetes to live a better life?"; (2) determined the most important research questions (short list); and (3) ranked research questions in order of importance (priorities). We aimed to recruit N = 800 participants, with approximate equal representation of diabetes type and family members. RESULTS: Participants (N = 661) were adults (aged 18+ years) in Australia with a self-reporting diagnosis of diabetes (type 1, n = 302; type 2, n = 204; prior/current gestational, n = 58; less common types, n = 22, or a family member, n = 75). Retention rates for Surveys 2 and 3 were 47% (n = 295) and 50% (n = 316), respectively. From 1549 open-text responses, 25 topics and 125 research questions were identified thematically. Research priorities differed by cohort, resulting in specific lists developed and ranked by each cohort. The top-ranked research question for the type 1 diabetes cohort was "How can diabetes technology be improved …?" and for the type 2 diabetes cohort: "How can insulin resistance be reversed …?". One question was common to the final lists of all cohorts: "What are the causes or triggers of diabetes?" Within cohorts, the top priorities were perceived as being of similar importance. CONCLUSIONS: The research priorities differ substantially by diabetes type and for family members. These findings should inform funding bodies and researchers, to align future research and its communication with community needs.

4.
Proc Natl Acad Sci U S A ; 121(18): e2319566121, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38648490

RESUMO

Respiratory virus infections in humans cause a broad-spectrum of diseases that result in substantial morbidity and mortality annually worldwide. To reduce the global burden of respiratory viral diseases, preventative and therapeutic interventions that are accessible and effective are urgently needed, especially in countries that are disproportionately affected. Repurposing generic medicine has the potential to bring new treatments for infectious diseases to patients efficiently and equitably. In this study, we found that intranasal delivery of neomycin, a generic aminoglycoside antibiotic, induces the expression of interferon-stimulated genes (ISGs) in the nasal mucosa that is independent of the commensal microbiota. Prophylactic or therapeutic administration of neomycin provided significant protection against upper respiratory infection and lethal disease in a mouse model of COVID-19. Furthermore, neomycin treatment protected Mx1 congenic mice from upper and lower respiratory infections with a highly virulent strain of influenza A virus. In Syrian hamsters, neomycin treatment potently mitigated contact transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In healthy humans, intranasal application of neomycin-containing Neosporin ointment was well tolerated and effective at inducing ISG expression in the nose in a subset of participants. These findings suggest that neomycin has the potential to be harnessed as a host-directed antiviral strategy for the prevention and treatment of respiratory viral infections.

6.
Appl Ergon ; 118: 104274, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38521001

RESUMO

This study investigates the impact of advanced driver-assistance systems on drivers' mental workload. Using a combination of physiological signals including ECG, EMG, EDA, EEG (af4 and fc6 channels from the theta band), and eye diameter data, this study aims to predict and categorize drivers' mental workload into low, adequate, and high levels. Data were collected from five different driving situations with varying cognitive demands. A functional linear regression model was employed for prediction, and the accuracy rate was calculated. Among the 31 tested combinations of physiological variables, 9 combinations achieved the highest accuracy result of 90%. These results highlight the potential benefits of utilizing raw physiological signal data and employing functional data analysis methods to understand and assess driver mental workload. The findings of this study have implications for the design and improvement of driver-assistance systems to optimize safety and performance.

7.
Acad Radiol ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38538510

RESUMO

BACKGROUND: The accuracy and completeness of self-disclosures by authors of imaging guidelines are not well known. OBJECTIVE: The aim of this study was to assess the accuracy of financial disclosures by US authors of ACR appropriateness criteria. METHODS: We reviewed financial disclosures provided by US-based authors of all ACR-AC published in 2019, 2021 and 2023. For each US- based author, payment reports were extracted from the Open Payments Database (OPD) in the previous 36 months related to general category and research payments categories. We analyzed each author individually to determine if the reported disclosures matched results from OPD. RESULTS: A total of 633 authorships, including 333 unique authors were included from 38 ACR AC articles in 2019, with 606 authorships (387 unique authors) from 35 ACR-AC articles published in 2021, and 540 authorships (367 unique authors) from 32 ACR AC articles published in 2023. Among authors who received industry payments, failure to disclose any financial relationship was seen in 125/147 unique authors in 2019, 142/148 authors in 2021 and 95/125 unique authors in 2023. The proportion of nondisclosed total value of payments was 86.1% in 2019, 88.6% in 2021 and 56.7% in 2023. General category payments were nondisclosed in 94.1% in 2019, 89.7% in 2021 and 94.4% in 2023 by payment value. CONCLUSION: Industry payments to authors of radiology guidelines are common and frequently undisclosed.

8.
bioRxiv ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38496452

RESUMO

Host response aimed at eliminating the infecting pathogen, as well as the pathogen itself, can cause tissue injury. Tissue injury leads to the release of a myriad of cellular components including mitochondrial DNA, which the host senses through pattern recognition receptors. How the sensing of tissue injury by the host shapes the anti-pathogen response remains poorly understood. In this study, we utilized mice that are deficient in toll-like receptor-9 (TLR9), which binds to unmethylated CpG DNA sequences such as those present in bacterial and mitochondrial DNA. To avoid direct pathogen sensing by TLR9, we utilized the influenza virus, which lacks ligands for TLR9, to determine how damage sensing by TLR9 contributes to anti-influenza immunity. Our data show that TLR9-mediated sensing of tissue damage promotes an inflammatory response during early infection, driven by the myeloid cells and associated cytokine responses. Along with the diminished inflammatory response, the absence of damage sensing through TLR9 led to impaired viral clearance manifested as a higher and prolonged influenza burden in the lung. The absence of TLR9 led to extensive infection of myeloid cells including monocytes and macrophages rendering them highly inflammatory, despite having a low initial inflammatory response. The persistent inflammation driven by infected myeloid cells led to persistent lung injury and impaired recovery in influenza-infected TLR9-/- mice. Further, we show elevated circulating TLR9 ligands in the plasma samples of patients with influenza, demonstrating its clinical relevance. Overall, over data show an essential role of damage sensing through TLR9 in promoting anti-influenza immunity.

10.
Biochemistry ; 62(21): 3126-3133, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37884446

RESUMO

The protein PARK7 (also known as DJ-1) has been implicated in several diseases, with the most notable being Parkinson's disease. While several molecular and cellular roles have been ascribed to DJ-1, there is no real consensus on what its true cellular functions are and how the loss of DJ-1 function may contribute to the pathogenesis of Parkinson's disease. Recent reports have implicated DJ-1 in the detoxification of several reactive metabolites that are produced during glycolytic metabolism, with the most notable being the α-oxoaldehyde species methylglyoxal. While it is generally agreed that DJ-1 is able to metabolize methylglyoxal to lactate, the mechanism by which it does so is hotly debated with potential implications for cellular function. In this work, we provide definitive evidence that recombinant DJ-1 produced in human cells prevents the stable glycation of other proteins through the conversion of methylglyoxal or a related alkynyl dicarbonyl probe to their corresponding α-hydroxy carboxylic acid products. This protective action of DJ-1 does not require a physical interaction with a target protein, providing direct evidence for a glutathione-free glyoxalase and not a deglycase mechanism of methylglyoxal detoxification. Stereospecific liquid chromatography-mass spectrometry (LC-MS) measurements further uncovered the existence of nonenzymatic production of racemic lactate from MGO under physiological buffer conditions, whereas incubation with DJ-1 predominantly produces l-lactate. Collectively, these studies provide direct support for the stereospecific conversion of MGO to l-lactate by DJ-1 in solution with negligible or no contribution of direct protein deglycation.


Assuntos
Doença de Parkinson , Aldeído Pirúvico , Humanos , Aldeído Pirúvico/química , Aldeído Pirúvico/metabolismo , Doença de Parkinson/metabolismo , Óxido de Magnésio , Ácido Láctico , Proteína Desglicase DJ-1
11.
Front Cell Dev Biol ; 11: 1254904, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37849737

RESUMO

SSc-ILD (scleroderma associated interstitial lung disease) is a complex rheumatic disease characterized in part by immune dysregulation leading to the progressive fibrotic replacement of normal lung architecture. Because improved treatment options are sorely needed, additional study of the fibroproliferative mechanisms mediating this disease has the potential to accelerate development of novel therapies. The contribution of innate immunity is an emerging area of investigation in SSc-ILD as recent work has demonstrated the mechanistic and clinical significance of the NLRP3 inflammasome and its associated cytokines of TNFα (tumor necrosis factor alpha), IL-1ß (interleukin-1 beta), and IL-18 in this disease. In this review, we will highlight novel pathophysiologic insights afforded by these studies and the potential of leveraging this complex biology for clinical benefit.

12.
J Neurosci ; 43(50): 8812-8824, 2023 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-37884349

RESUMO

Accumulation of amyloid-ß peptide (Aß) aggregates in synapses may contribute to the profound synaptic loss characteristic of Alzheimer's disease (AD). The origin of synaptic Aß aggregates remains elusive, but loss of endosomal proteostasis may trigger their formation. In this study, we identified the synaptic compartments where Aß accumulates, and performed a longitudinal analysis of synaptosomes isolated from brains of TgCRND8 APP transgenic mice of either sex. To evaluate the specific contribution of Aß-degrading protease endothelin-converting enzyme (ECE-1) to synaptic/endosomal Aß homeostasis, we analyzed the effect of partial Ece1 KO in brain and complete ECE1 KO in SH-SY5Y cells. Global inhibition of ECE family members was used to further assess their role in preventing synaptic Aß accumulation. Results showed that, before extracellular amyloid deposition, synapses were burdened with detergent-soluble Aß monomers, oligomers, and fibrils. Levels of all soluble Aß species declined thereafter, as Aß42 turned progressively insoluble and accumulated in Aß-producing synaptic endosomal vesicles with characteristics of multivesicular bodies. Accordingly, fibrillar Aß was detected in brain exosomes. ECE-1-deficient mice had significantly increased endogenous synaptosomal Aß42 levels, and protease inhibitor experiments showed that, in TgCRND8 mice, synaptic Aß42 became nearly resistant to degradation by ECE-related proteases. Our study supports that Aß accumulating in synapses is produced locally, within endosomes, and does not require the presence of amyloid plaques. ECE-1 is a determinant factor controlling the accumulation and fibrillization of nascent Aß in endosomes and, in TgCRND8 mice, Aß overproduction causes rapid loss of Aß42 solubility that curtails ECE-mediated degradation.SIGNIFICANCE STATEMENT Deposition of aggregated Aß in extracellular plaques is a defining feature of AD. Aß aggregates also accumulate in synapses and may contribute to the profound synaptic loss and cognitive dysfunction typical of the disease. However, it is not clear whether synaptotoxic Aß is mainly derived from plaques or if it is produced and aggregated locally, within affected synaptic compartments. Filling this knowledge gap is important for the development of an effective treatment for AD, as extracellular and intrasynaptic pools of Aß may not be equally modulated by immunotherapies or other therapeutic approaches. In this manuscript, we provide evidence that Aß aggregates building up in synapses are formed locally, within synaptic endosomes, because of disruptions in nascent Aß proteostasis.


Assuntos
Doença de Alzheimer , Amiloidose , Neuroblastoma , Humanos , Camundongos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Neurônios/metabolismo , Neuroblastoma/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Camundongos Transgênicos , Endossomos/metabolismo , Placa Amiloide/metabolismo
13.
J Safety Res ; 86: 298-310, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37718057

RESUMO

INTRODUCTION: The prediction of when the driver will react to a change in the lead vehicle motion is critical for assessing rear-end crash risk using car-following models. Past studies have assumed constant reaction time and driver's continuous reaction. However, these assumptions are not valid as the driver's reaction time can vary in different car-following situations and the driver does not continuously react to the lead vehicle motion. Thus, this study predicted the driver's reaction time using the Wiedemann car-following model and the Accumulator model. The Accumulator model assumes the driver's start of reaction based on the accumulation of looming and thereby reflects the driver's intermittent reaction. METHOD: Fifty drivers' behavior was observed using a driving simulator in two scenarios: (1) approach and follow a moving lead vehicle and (2) approach a stopped lead vehicle. The Accumulator model predicted the reaction times based on different looming variables (angular velocity and tau-inverse), lead vehicle type (car and truck), and lead vehicle brake lights (on or off). RESULTS: The Accumulator model showed lower prediction errors of the reaction time than the Wiedemann model, which assumes reaction based on the fixed looming threshold. The Accumulator model predicted the reaction times more accurately when it was calibrated with the angular velocity due to width and height of lead vehicles. Moreover, the Accumulator model with tau-inverse produced the smallest prediction error of reaction times among different Accumulator models and the Wiedemann model when lead vehicle brake lights were on. CONCLUSIONS: This study demonstrates that the Accumulator model is a promising method of predicting the driver's reaction time in car-following situations, which affects rear-end crash risk. PRACTICAL APPLICATIONS: The Accumulator model can be incorporated into a car-following model for the prediction of reaction times and can estimate the rear-end collision risk of vehicles more accurately.


Assuntos
Condução de Veículo , Tempo de Reação , Humanos
14.
Genes (Basel) ; 14(8)2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37628569

RESUMO

Krabbe disease (KD) is a progressive and devasting neurological disorder that leads to the toxic accumulation of psychosine in the white matter of the central nervous system (CNS). The condition is inherited via biallelic, loss-of-function mutations in the galactosylceramidase (GALC) gene. To rescue GALC gene function in the CNS of the twitcher mouse model of KD, an adeno-associated virus serotype 1 vector expressing murine GALC under control of a chicken ß-actin promoter (AAV1-GALC) was administered to newborn mice by unilateral intracerebroventricular injection. AAV1-GALC treatment significantly improved body weight gain and survival of the twitcher mice (n = 8) when compared with untreated controls (n = 5). The maximum weight gain after postnatal day 10 was significantly increased from 81% to 217%. The median lifespan was extended from 43 days to 78 days (range: 74-88 days) in the AAV1-GALC-treated group. Widespread expression of GALC protein and alleviation of KD neuropathology were detected in the CNS of the treated mice when examined at the moribund stage. Functionally, elevated levels of psychosine were completely normalized in the forebrain region of the treated mice. In the posterior region, which includes the mid- and the hindbrain, psychosine was reduced by an average of 77% (range: 53-93%) compared to the controls. Notably, psychosine levels in this region were inversely correlated with body weight and lifespan of AAV1-GALC-treated mice, suggesting that the degree of viral transduction of posterior brain regions following ventricular injection determined treatment efficacy on growth and survivability, respectively. Overall, our results suggest that viral vector delivery via the cerebroventricular system can partially correct psychosine accumulation in brain that leads to slower disease progression in KD.


Assuntos
Leucodistrofia de Células Globoides , Substância Branca , Animais , Camundongos , Galactosilceramidase , Leucodistrofia de Células Globoides/genética , Leucodistrofia de Células Globoides/terapia , Psicosina , Longevidade/genética , Hidrolases , Prosencéfalo , Peso Corporal
15.
Optom Vis Sci ; 100(8): 499-506, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37499165

RESUMO

SIGNIFICANCE: The reports from optical coherence tomography (OCT) instruments depend on a reference database (RDB) of healthy eyes. Although these RDBs tend to be relatively small, they are time consuming and expensive to obtain. A larger RDB should improve our ability to screen for diseases such as glaucoma. PURPOSE: To explore the feasibility of developing a large RDB from OCT scans obtained by optometrists as part of their pre-test gathering of information, we tested the hypothesis that these scans are of sufficient quality for an RDB and contain a relatively low base rate of glaucoma and other pathologies (OPs). METHODS: Optical coherence tomography widefield (12 × 9 mm) scans from 400 eyes of 400 patients were randomly selected from a data set of more than 49,000 scans obtained from four optometry sites. Based on a commercial OCT report and a previously validated reading center method, two OCT graders categorized eyes as unacceptable to use for RDB, healthy (H), optic neuropathy consistent with glaucoma (ON-G), glaucoma suspect, or OPs. RESULTS: Overall, 29 (7.25%) of the eyes were graded unacceptable. Of the remaining 371 eyes, 352 (94.9%) were graded H. Although, for one site, 7.4% of the eligible eyes were graded ON-G, the average for the other three sites was 1.4%. Adjustments of the reading center criteria resulted in exclusion of more than half of these ON-G and OP eyes. CONCLUSIONS: The OCT scans obtained from optometry practices as part of their pre-test regimen are of sufficient quality for an RDB and contain a relatively low base rate of glaucoma and OPs. With the suggested exclusion criteria, the scans from optometry practices that are primarily involved in refraction and medical screening services should yield a large, real-world RDB with improved specificity and a base rate of glaucoma and/or OPs comparable with existing RDB.


Assuntos
Glaucoma , Optometria , Humanos , Tomografia de Coerência Óptica/métodos , Testes de Campo Visual/métodos , Campos Visuais , Glaucoma/diagnóstico , Células Ganglionares da Retina/patologia , Pressão Intraocular
16.
Accid Anal Prev ; 188: 107097, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37163853

RESUMO

Whereas aggressive driving mainly causes speed-related crashes, aggressive driving may be reduced to improve road safety by identifying aggressive driving behaviour, aggressive drivers' characteristics, and their underlying motivational and psychological processes. Previous studies show that both driving performance and self-reported measures of aggressive driving are effective means to identify aggressive drivers. However, these studies assessed aggressive driving patterns across only a limited number of events, did not relate driver characteristics to aggressive driving in each event, and used chiefly vehicle kinematics variables (e.g., mean speed), but not vehicle dynamics variables (e.g., brake pedal force) which better capture driver reaction and decision-making. To address these limitations, this study assessed driver characteristics, self-reported psychological measures, and driving performance measures associated with aggressive driving among 55 drivers' behaviours in 9driving events using a driving simulator and survey responses. The results of structural equation models showed that unique aggressive driving patterns and driver characteristics related to aggressive driving vary among different driving events. As such, we recommend road safety policies to reduce aggressive driving based on the findings in this study.


Assuntos
Direção Agressiva , Condução de Veículo , Humanos , Autorrelato , Acidentes de Trânsito/prevenção & controle , Modelos Teóricos , Agressão
17.
Ergonomics ; : 1-12, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37083452

RESUMO

The purpose of this study is to investigate the change in body dimensions over time in both Western (US) and Eastern (Korea) populations. In order to analyse the change of body dimension between the past and present and between western and eastern population, 13 body dimensions relating to automobile driver seat design were extracted from the ANSUR and Size Korea datasets at two time points, the past (ANSUR I: 1988, Size Korea: 1992) and the present (ANSUR II: 2012, Size Korea: 2012). Most of the dimensions differed significantly between past and present, as well as between the US and Korea. Overall, the data show an increasing trend of body dimensions over time for both genders. Based on the results, all countries should be encouraged to conduct periodic and national anthropometric research because body dimensions are continuously changing over time worldwide.Practitioner summary: This paper describes a study that investigates the changes in body dimensions over time in Western (US) and Eastern (Korean) populations. Findings indicate increasing trends in most dimensions for both populations, crucial for user-friendly product design and preventing hazards caused by faulty products.

18.
ACS Chem Biol ; 18(1): 91-101, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36562291

RESUMO

Methylglyoxal (MGO), a reactive metabolite byproduct of glucose metabolism, is known to form a variety of posttranslational modifications (PTMs) on nucleophilic amino acids. For example, cysteine, the most nucleophilic proteinogenic amino acid, forms reversible hemithioacetal and stable mercaptomethylimidazole adducts with MGO. The high reactivity of cysteine toward MGO and the rate of formation of such modifications provide the opportunity for mechanisms by which proteins and pathways might rapidly sense and respond to alterations in levels of MGO. This indirect measure of alterations in glycolytic flux would thereby allow disparate cellular processes to dynamically respond to changes in nutrient availability and utilization. Here we report the use of quantitative LC-MS/MS-based chemoproteomic profiling approaches with a cysteine-reactive probe to map the proteome-wide landscape of MGO modification of cysteine residues. This approach led to the identification of many sites of potential functional regulation by MGO. We further characterized the role that such modifications have in a catalytic cysteine residue in a key metabolic enzyme and the resulting effects on cellular metabolism.


Assuntos
Cisteína , Aldeído Pirúvico , Aldeído Pirúvico/química , Cisteína/química , Cromatografia Líquida , Óxido de Magnésio , Espectrometria de Massas em Tandem , Aminoácidos
19.
Neurobiol Dis ; 174: 105862, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36113749

RESUMO

Krabbe Disease (KD) is an autosomal recessive disorder that results from loss-of-function mutations in the GALC gene, which encodes lysosomal enzyme galactosylceramidase (GALC). Functional deficiency of GALC is toxic to myelin-producing cells, which leads to progressive demyelination in both the central and peripheral nervous systems. It is hypothesized that accumulation of psychosine, which can only be degraded by GALC, is a primary initiator of pathologic cascades. Despite the central role of GALC in KD pathomechanism, investigations of GALC deficiency at a protein level are largely absent, due in part, to the lack of sensitive antibodies in the field. Leveraging two custom antibodies that can detect GALC at endogenous levels, we demonstrated that GALC protein is predominantly localized to oligodendrocytes in cerebral white matter of an infant brain, consistent with its functional role in myelination. Mature GALC could also be quantitatively detected as a 26 kDa band by western blotting and correlated to enzyme activity in brain tissues. The p.Ile562Thr polymorphic variant, which is over-represented in the KD population, was associated with reduced mature GALC protein and activity. In three infantile KD cases, homozygous null mutations in GALC lead to deficiency in total GALC protein and activity. Interestingly, although GALC activity was absent, normal levels of total GALC protein were detected by a sandwich ELISA using our custom antibodies in a later-onset KD brain, which suggests that the assay has the potential to differentiate infantile- and later-onset KD cases. Among the infantile KD cases, we quantified a 5-fold increase in psychosine levels, and observed increased levels of acid ceramidase, a key enzyme for psychosine production, and hyperglycosylated lysosomal-associated membrane protein 1, a marker for lysosomal activation, in periventricular white matter, a major pathological brain region, when compared with age-matched normal controls. While near complete demyelination was observed in these cases, we quantified that an early-infantile case (age of death at 10 months) had about 3-fold increases in both globoid cells, a pathological hallmark for KD, and CD8-positive T lymphocytes, a pathological marker for multiple sclerosis, in the white matter when compared with a slower progressing infantile case (age of death at 21 months), which suggests a positive correlation between clinical severity and neuropathology. Taken together, our findings have advanced the understanding of GALC protein biology in the context of normal and KD brain white matter. We also revealed new neuropathological changes that may provide insights to understand KD pathogenesis.


Assuntos
Leucodistrofia de Células Globoides , Substância Branca , Humanos , Galactosilceramidase/genética , Galactosilceramidase/metabolismo , Leucodistrofia de Células Globoides/genética , Leucodistrofia de Células Globoides/patologia , Psicosina/metabolismo , Substância Branca/patologia , Mutação
20.
Sci Adv ; 8(34): eabo5115, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-36001672

RESUMO

Invasive species are a key driver of the global biodiversity crisis, but the drivers of invasiveness, including the role of pathogens, remain debated. We investigated the genomic basis of invasiveness in Ambrosia artemisiifolia (common ragweed), introduced to Europe in the late 19th century, by resequencing 655 ragweed genomes, including 308 herbarium specimens collected up to 190 years ago. In invasive European populations, we found selection signatures in defense genes and lower prevalence of disease-inducing plant pathogens. Together with temporal changes in population structure associated with introgression from closely related Ambrosia species, escape from specific microbial enemies likely favored the plant's remarkable success as an invasive species.


Assuntos
Ambrosia , Espécies Introduzidas , Ambrosia/genética , Europa (Continente) , Genômica , Análise de Sequência de DNA
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