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2.
Appl Environ Microbiol ; 90(5): e0169423, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38624219

RESUMO

Given the multitude of extracellular enzymes at their disposal, many of which are designed to degrade nature's polymers (lignin, cutin, cellulose, etc.), fungi are adept at targeting synthetic polyesters with similar chemical composition. Microbial-influenced deterioration of xenobiotic polymeric surfaces is an area of interest for material scientists as these are important for the conservation of the underlying structural materials. Here, we describe the isolation and characterization of the Papiliotrema laurentii 5307AH (P. laurentii) cutinase, Plcut1. P. laurentii is basidiomycete yeast with the ability to disperse Impranil-DLN (Impranil), a colloidal polyester polyurethane, in agar plates. To test whether the fungal factor involved in this clearing was a secreted enzyme, we screened the ability of P. laurentii culture supernatants to disperse Impranil. Using size exclusion chromatography (SEC), we isolated fractions that contained Impranil-clearing activity. These fractions harbored a single ~22 kD band, which was excised and subjected to peptide sequencing. Homology searches using the peptide sequences identified, revealed that the protein Papla1 543643 (Plcut1) displays similarities to serine esterase and cutinase family of proteins. Biochemical assays using recombinant Plcut1 confirmed that this enzyme has the capability to hydrolyze Impranil, soluble esterase substrates, and apple cutin. Finally, we confirmed the presence of the Plcut1 in culture supernatants using a custom antibody that specifically recognizes this protein. The work shown here supports a major role for the Plcut1 in the fungal degradation of natural polyesters and xenobiotic polymer surfaces.IMPORTANCEFungi play a vital role in the execution of a broad range of biological processes that drive ecosystem function through production of a diverse arsenal of enzymes. However, the universal reactivity of these enzymes is a current problem for the built environment and the undesired degradation of polymeric materials in protective coatings. Here, we report the identification and characterization of a hydrolase from Papiliotrema laurentii 5307AH, an aircraft-derived fungal isolate found colonizing a biodeteriorated polymer-coated surface. We show that P. laurentii secretes a cutinase capable of hydrolyzing soluble esters as well as ester-based compounds forming solid surface coatings. These findings indicate that this fungus plays a significant role in biodeterioration through the production of a cutinase adept at degrading ester-based polymers, some of which form the backbone of protective surface coatings. The work shown here provides insights into the mechanisms employed by fungi to degrade xenobiotic polymers.


Assuntos
Hidrolases de Éster Carboxílico , Proteínas Fúngicas , Poliésteres , Proteínas Recombinantes , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Poliésteres/metabolismo , Hidrólise
3.
Science ; 383(6689): 1332-1337, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38513021

RESUMO

Engineered dissipative reservoirs have the potential to steer many-body quantum systems toward correlated steady states useful for quantum simulation of high-temperature superconductivity or quantum magnetism. Using up to 49 superconducting qubits, we prepared low-energy states of the transverse-field Ising model through coupling to dissipative auxiliary qubits. In one dimension, we observed long-range quantum correlations and a ground-state fidelity of 0.86 for 18 qubits at the critical point. In two dimensions, we found mutual information that extends beyond nearest neighbors. Lastly, by coupling the system to auxiliaries emulating reservoirs with different chemical potentials, we explored transport in the quantum Heisenberg model. Our results establish engineered dissipation as a scalable alternative to unitary evolution for preparing entangled many-body states on noisy quantum processors.

4.
Water Environ Res ; 96(3): e11009, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38444297

RESUMO

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are an emerging issue in wastewater treatment. High-temperature thermal processes, incineration being time-tested, offer the opportunity to destroy and change the composition of PFAS. The fate of PFAS has been documented through wastewater sludge incinerators, including a multiple hearth furnace (MHF) and a fluidized bed furnace (FBF). The dewatered wastewater sludge feedstock averaged 247- and 1280-µmol targeted PFAS per sample run in MHF and FBF feed, respectively. Stack emissions (reportable for all targeted PFAS from MHF only) averaged 5% of that value with shorter alkyl chain compounds comprising the majority of the targeted PFAS. Wet scrubber water streams accumulated nonpolar fluorinated organics from the furnace exhaust with an average of 0.740- and 0.114-mol F- per sample run, for the MHF and FBF, respectively. Simple alkane PFAS measured at the stack represented 0.5%-4.5% of the total estimated facility greenhouse gas emissions. PRACTITIONER POINTS: The MHF emitted six short chain PFAS from the stack, which were shorter alkyl chain compounds compared with sludge PFAS. The FBF did not consistently emit reportable PFAS from the stack, but contamination complicated the assessment. Five percent of the MHF sludge molar PFAS load was reported in the stack. MHF and FBF wet scrubber water streams accumulated nonpolar fluorinated organics from the furnace exhaust. Ultra-short volatile alkane PFAS measured at the stack represented 0.5%-4.5% of the estimated facility greenhouse gas emissions.


Assuntos
Fluorocarbonos , Gases de Efeito Estufa , Esgotos , Águas Residuárias , Alcanos , Incineração , Água
5.
J Clin Immunol ; 44(3): 66, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363477

RESUMO

B cells and their secreted antibodies are fundamental for host-defense against pathogens. The generation of high-affinity class switched antibodies results from both somatic hypermutation (SHM) of the immunoglobulin (Ig) variable region genes of the B-cell receptor and class switch recombination (CSR) which alters the Ig heavy chain constant region. Both of these processes are initiated by the enzyme activation-induced cytidine deaminase (AID), encoded by AICDA. Deleterious variants in AICDA are causal of hyper-IgM syndrome type 2 (HIGM2), a B-cell intrinsic primary immunodeficiency characterised by recurrent infections and low serum IgG and IgA levels. Biallelic variants affecting exons 2, 3 or 4 of AICDA have been identified that impair both CSR and SHM in patients with autosomal recessive HIGM2. Interestingly, B cells from patients with autosomal dominant HIGM2, caused by heterozygous variants (V186X, R190X) located in AICDA exon 5 encoding the nuclear export signal (NES) domain, show abolished CSR but variable SHM. We herein report the immunological and functional phenotype of two related patients presenting with common variable immunodeficiency who were found to have a novel heterozygous variant in AICDA (L189X). This variant led to a truncated AID protein lacking the last 10 amino acids of the NES at the C-terminal domain. Interestingly, patients' B cells carrying the L189X variant exhibited not only greatly impaired CSR but also SHM in vivo, as well as CSR and production of IgG and IgA in vitro. Our findings demonstrate that the NES domain of AID can be essential for SHM, as well as for CSR, thereby refining the correlation between AICDA genotype and SHM phenotype as well as broadening our understanding of the pathophysiology of HIGM disorders.


Assuntos
Citidina Desaminase , Síndrome de Imunodeficiência com Hiper-IgM , Switching de Imunoglobulina , Humanos , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Síndrome de Imunodeficiência com Hiper-IgM/genética , Imunoglobulina A/genética , Switching de Imunoglobulina/genética , Imunoglobulina G/genética , Fenótipo , Hipermutação Somática de Imunoglobulina
6.
J Sch Health ; 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38268088

RESUMO

BACKGROUND: As summarized in this article, the widespread implementation of modern school health education (SHE) could become one of the most effective means available to improve the well-being of people in the United States and in other nations. However, the development and evolution of SHE largely remains unorganized, underdeveloped, and neglected by health and education agencies, policymakers, and the public. METHODS: Essential to the development of any scientific discipline, scientists today use the word ontology to refer to efforts to organize knowledge in particular domains. A useful working definition of a scientific ontology is an explicit, formal specification of a shared conceptualization-a systematic set of shared terms and an explication of their interrelationships. Nine interdependent questions are outlined to help guide the development of an initial, broad, and actionable scientific ontology for SHE. RESULTS: Whether and how we respond to these questions arguably will determine the future of SHE research, policy, practice, and equity in the United States. CONCLUSIONS: An initial ontology might help conceptualize, inform, and facilitate more systematic and strategic local, state, national, and international deliberations and actions to improve SHE.

7.
EBioMedicine ; 99: 104941, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38168586

RESUMO

BACKGROUND: Steroidogenic factor 1 (SF-1/NR5A1) is essential for human sex development. Heterozygous NR5A1/SF-1 variants manifest with a broad range of phenotypes of differences of sex development (DSD), which remain unexplained. METHODS: We conducted a retrospective analysis on the so far largest international cohort of individuals with NR5A1/SF-1 variants, identified through the I-DSD registry and a research network. FINDINGS: Among 197 individuals with NR5A1/SF-1 variants, we confirmed diverse phenotypes. Over 70% of 46, XY individuals had a severe DSD phenotype, while 90% of 46, XX individuals had female-typical sex development. Close to 100 different novel and known NR5A1/SF-1 variants were identified, without specific hot spots. Additionally, likely disease-associated variants in other genes were reported in 32 individuals out of 128 tested (25%), particularly in those with severe or opposite sex DSD phenotypes. Interestingly, 48% of these variants were found in known DSD or SF-1 interacting genes, but no frequent gene-clusters were identified. Sex registration at birth varied, with <10% undergoing reassignment. Gonadectomy was performed in 30% and genital surgery in 58%. Associated organ anomalies were observed in 27% of individuals with a DSD, mainly concerning the spleen. Intrafamilial phenotypes also varied considerably. INTERPRETATION: The observed phenotypic variability in individuals and families with NR5A1/SF-1 variants is large and remains unpredictable. It may often not be solely explained by the monogenic pathogenicity of the NR5A1/SF-1 variants but is likely influenced by additional genetic variants and as-yet-unknown factors. FUNDING: Swiss National Science Foundation (320030-197725) and Boveri Foundation Zürich, Switzerland.


Assuntos
Desenvolvimento Sexual , Recém-Nascido , Humanos , Feminino , Mutação , Fator Esteroidogênico 1/genética , Estudos Retrospectivos , Fenótipo , Desenvolvimento Sexual/genética
9.
J Cyst Fibros ; 23(1): 155-160, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37845149

RESUMO

BACKGROUND: The cystic fibrosis transmembrane conductance regulator (CFTR) modulator elexacaftor/tezacaftor/ivacaftor (E/T/I) is highly effective clinically for those with at least one F508del-CFTR allele. The effects of E/T/I on mucociliary clearance (MCC) and sputum properties are unknown. We, therefore, sought to characterize the effects of E/T/I on in vivo MCC and sputum characteristics hypothesized to impact mucus transport. METHODS: Forty-four participants ≥12 years of age were enrolled into this prospective, observational trial prior to initiation of E/T/I and had baseline measurement of MCC and characterization of induced sputum and exhaled breath condensate (EBC) samples. Study procedures were repeated after 1 month of E/T/I treatment. RESULTS: Average age was 27.7 years with baseline forced expiratory volume in 1 second (FEV1) of 78.2 % predicted. 52 % of subjects had previously been treated with a 2-drug CFTR modulator combination. The average whole lung MCC rate measured over 60 min (WLAveClr60) significantly improved from baseline to post-E/T/I (14.8 vs. 22.8 %; p = 0.0002), as did other MCC indices. Sputum% solids also improved (modeled mean 3.4 vs. 2.2 %; p<0.0001), whereas non-significant reductions in sputum macrorheology (G', G") were observed. No meaningful changes in exhaled breath condensate endpoints (sialic acid:urea ratio, pH) were observed. CONCLUSIONS: E/T/I improved the hydration of respiratory secretions (% solids) and markedly accelerated MCC. These data confirm the link between CFTR function, mucus solid content, and MCC and help to define the utility of MCC and mucus-related bioassays in future efforts to restore CFTR function in all people with CF.


Assuntos
Fibrose Cística , Indóis , Pirazóis , Piridinas , Pirrolidinas , Quinolonas , Humanos , Adulto , Fibrose Cística/diagnóstico , Fibrose Cística/tratamento farmacológico , Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística , Depuração Mucociliar , Estudos Prospectivos , Aminofenóis/uso terapêutico , Benzodioxóis/uso terapêutico , Muco , Mutação , Agonistas dos Canais de Cloreto/uso terapêutico
10.
Radiography (Lond) ; 30(1): 28-36, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37866155

RESUMO

INTRODUCTION: Autism is a neuro-developmental condition which affects the social-emotional skills, behaviour, language, communication skills and flexibility of thoughts of an individual and their sensory processing. This can result in Autistic service users finding it difficult to navigate current healthcare provision and cope with the unpredictable environment. This paper explores the experiences of parents of Autistic children when attending the diagnostic imaging department for an X-ray examination. METHODS: A cross sectional, mixed methods approach was adopted and the initial phase consisting of an online survey for parents to complete is the subject of this paper. The quantitative data was analysed using descriptive statistics and cross comparison between questions was also completed. Thematic analysis was taken to analyse the data from the two open questions at the end of the survey. RESULTS: The online survey results are presented in this paper under four key themes; waiting times and environment, forms of communication, lack of understanding of staff regarding Autism and preparation for the X-ray examination. CONCLUSION: The overall rating of the parents' experience whilst in the X-ray/diagnostic imaging department was positive, however there are several areas which received low scores which need further attention. These were waiting areas, waiting times, staff development and patient preparation. IMPLICATIONS FOR PRACTICE: The development of more inclusive waiting areas is needed, more effective lines of communication between staff to expedite the patient journey where possible, staff development of both radiographers and also support staff and the review of design of more accessible and inclusive patient information.


Assuntos
Transtorno Autístico , Criança , Humanos , Transtorno Autístico/diagnóstico por imagem , Transtorno Autístico/psicologia , Raios X , Estudos Transversais , Pais/psicologia , Radiografia
11.
Heliyon ; 9(12): e22724, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38107300

RESUMO

Gender differences in productivity are one of the major obstacles impeding the development of agriculture in Africa and Nigerian particularly. With the Oaxaca-Blinder (OB) and exogenous switching treatment regression (ESTER) models, this study investigates the causes of the productivity differences among 360 sampled rice farmers in Nigeria as well as gender inequality in agricultural productivity. The findings showed that there is an inequalities between men and women, which contributes to a gender productivity gap of almost 29 % in favour of men. As a result, plots managed by women are 29 % less productive than plots handled by men. The analysis of the factors influencing gender variations in production reveals that the endowment component, which accounts for 15 % of the productivity gap, is significantly influenced by marital status, education, farm size, and access to market information. Similarly, the ESTER results show that the rice yield of FHHs would have decreased by 25.41 kg/ha (a 1.02 % reduction) if they had been assigned the same returns to the observed features of MHHs. This difference is significant at the 1 % level. Thus, the findings imply that the FHHs are not at a yield disadvantage when compared to the MHHs. Therefore, it can be said that there are gender productivity disparities in the Nigerian agricultural industry. As such, policy interventions aimed at empowering women must take these disparities into consideration as well as the causes that contribute to them. Overall, the results demonstrate that although policymakers and their development partners can use improved technologies to increase MHH and FHH yields, reducing the difference in market linkages is necessary to close the gender gap in rice productivity and provide FHHs with equal access to the market.

13.
Cell Mol Immunol ; 20(7): 777-793, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37161048

RESUMO

As chronic antigenic stimulation from infection and autoimmunity is a feature of primary antibody deficiency (PAD), analysis of affected patients could yield insights into T-cell differentiation and explain how environmental exposures modify clinical phenotypes conferred by single-gene defects. CD57 marks dysfunctional T cells that have differentiated after antigenic stimulation. Indeed, while circulating CD57+ CD4+ T cells are normally rare, we found that they are increased in patients with PAD and markedly increased with CTLA4 haploinsufficiency or blockade. We performed single-cell RNA-seq analysis of matched CD57+ CD4+ T cells from blood and tonsil samples. Circulating CD57+ CD4+ T cells (CD4cyt) exhibited a cytotoxic transcriptome similar to that of CD8+ effector cells, could kill B cells, and inhibited B-cell responses. CTLA4 restrained the formation of CD4cyt. While CD57 also marked an abundant subset of follicular helper T cells, which is consistent with their antigen-driven differentiation, this subset had a pre-exhaustion transcriptomic signature marked by TCF7, TOX, and ID3 expression and constitutive expression of CTLA4 and did not become cytotoxic even after CTLA4 inhibition. Thus, CD57+ CD4+ T-cell cytotoxicity and exhaustion phenotypes are compartmentalised between blood and germinal centers. CTLA4 is a key modifier of CD4+ T-cell cytotoxicity, and the pathological CD4cyt phenotype is accentuated by infection.


Assuntos
Linfócitos B , Linfócitos T CD4-Positivos , Linfócitos B/metabolismo , Antígenos CD57/metabolismo , Diferenciação Celular , Antígeno CTLA-4 , Humanos
14.
Neuro Oncol ; 25(8): 1498-1506, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37010875

RESUMO

BACKGROUND: Prospective data on maintenance therapy with bevacizumab for persons with NF2-related schwannomatosis (NF2-SWN) is lacking. In this prospective multicenter phase II study, we evaluated the efficacy, safety, and tolerability of bevacizumab for maintenance therapy in children and adults with NF2-SWN and hearing loss due to vestibular schwannomas (VS). METHODS: Following induction therapy, participants received bevacizumab 5 mg/kg every 3 weeks for 18 months. Participants were monitored for changes in hearing, tumor size, and quality of life (QOL), and for adverse events. Hearing loss was defined as a statistically significant decline in word recognition score (WRS) or pure-tone average compared to the study baseline; tumor growth was defined as >20% increase in volume compared to baseline. RESULTS: Twenty participants with NF2-SWN (median age 23.5 years; range, 12.5-62.5 years) with hearing loss in the target ear (median WRS 70%, range 2%-94%) received maintenance bevacizumab. Freedom from hearing loss in the target ear was 95% after 48 weeks, 89% after 72 weeks, and 70% after 98 weeks. Freedom from tumor growth in the target VS was 94% after 48 weeks, 89% after 72 weeks, and 89% after 98 weeks. NF2-related QOL remained stable for 98 weeks whereas tinnitus-related distress decreased. Maintenance bevacizumab was well tolerated, with 3 participants (15%) discontinuing treatment due to adverse events. CONCLUSIONS: Maintenance bevacizumab (5 mg/kg every 3 weeks) is associated with high rates of hearing and tumor stability during 18 months of follow-up. No new unexpected adverse events related to bevacizumab were identified in this population.


Assuntos
Perda Auditiva , Neurofibromatose 2 , Neuroma Acústico , Adulto , Criança , Humanos , Adulto Jovem , Neuroma Acústico/complicações , Neuroma Acústico/tratamento farmacológico , Neuroma Acústico/patologia , Bevacizumab/uso terapêutico , Qualidade de Vida , Estudos Prospectivos , Resultado do Tratamento , Neurofibromatose 2/complicações , Neurofibromatose 2/tratamento farmacológico , Perda Auditiva/induzido quimicamente
15.
Br J Pharmacol ; 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055379

RESUMO

BACKGROUND AND PURPOSE: Wnt binding to Frizzleds (FZD) is a crucial step that leads to the initiation of signalling cascades governing multiple processes during embryonic development, stem cell regulation and adult tissue homeostasis. Recent efforts have enabled us to shed light on Wnt-FZD pharmacology using overexpressed HEK293 cells. However, assessing ligand binding at endogenous receptor expression levels is important due to differential binding behaviour in a native environment. Here, we study FZD paralogue, FZD7 , and analyse its interactions with Wnt-3a in live CRISPR-Cas9-edited SW480 cells typifying colorectal cancer. EXPERIMENTAL APPROACH: SW480 cells were CRISPR-Cas9-edited to insert a HiBiT tag on the N-terminus of FZD7 , preserving the native signal peptide. These cells were used to study eGFP-Wnt-3a association with endogenous and overexpressed HiBiT-FZD7 using NanoBiT/bioluminescence resonance energy transfer (BRET) and NanoBiT to measure ligand binding and receptor internalization. KEY RESULTS: With this new assay the binding of eGFP-Wnt-3a to endogenous HiBiT-FZD7 was compared with overexpressed receptors. Receptor overexpression results in increased membrane dynamics, leading to an apparent decrease in binding on-rate and consequently in higher, up to 10 times, calculated Kd . Thus, measurements of binding affinities to FZD7 obtained in overexpressed cells are suboptimal compared with the measurements from endogenously expressing cells. CONCLUSIONS AND IMPLICATIONS: Binding affinity measurements in the overexpressing cells fail to replicate ligand binding affinities assessed in a (patho)physiologically relevant context where receptor expression is lower. Therefore, future studies on Wnt-FZD7 binding should be performed using receptors expressed under endogenous promotion.

17.
HLA ; 102(1): 13-27, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36851856

RESUMO

The CDC crossmatch test is being phased out in solid organ donor allocation, and standard luminex single antigen bead assays do not differentiate complement activating function of HLA antibodies. The current study investigated the LIFECODES C3d-binding assay to determine if it could accurately predict actual T and B cell CDC results in a cohort of highly sensitised patients. Nineteen serum samples from different highly sensitised solid organ patients were crossmatched against cells from 62 unique donors, with 174 total T and B cell crossmatches performed. The sera also underwent SAB assay using OLI and LC platforms, and C3d-binding assay. Complement activating ability of each unique HLA antibody specificity detected using SAB was assigned based on the actual CDC results, which was then used to determine the accuracy of the C3d-binding assay. The C3d-binding assay was found to be highly accurate, with sensitivity of 95%, specificity 89% and negative predictive value 97% for class I DSA and the T cell CDC crossmatch results. Furthermore, we found 100% accuracy for prediction of the complement activating function of HLA-C antibodies. Negative predictive value of above 90% was also found for HLA class II DSA. C3d-binding proved more accurate than virtual crossmatch alone to predict CDC results. This study confirms that the C3d-binding assay predicts actual CDC crossmatch results accurately. In particular, the high negative predictive value of the C3d-binding assay may be extremely useful to define HLA antibodies that do not activate complement in highly sensitised recipients.


Assuntos
Transplante de Rim , Humanos , Estados Unidos , Transplante de Rim/métodos , Rejeição de Enxerto , Antígenos HLA , Alelos , Anticorpos , Proteínas do Sistema Complemento , Teste de Histocompatibilidade/métodos , Centers for Disease Control and Prevention, U.S. , Isoanticorpos
18.
Intern Med J ; 53(2): 280-284, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36822603

RESUMO

Kidney donor allocation can occasionally be difficult in Australia given a small population spread over vast distances. Therefore, between 2017 and 2019 our service allowed transplantation from deceased donors into local (same-state) preemptive recipients, only if no well-matched dialysis-dependent transplant waitlist recipient was available. Transplantation using this novel allocation pathway was associated with good clinical and immunological outcomes.


Assuntos
Transplante de Rim , Humanos , Austrália Ocidental , Doadores de Tecidos , Diálise Renal , Rim , Sobrevivência de Enxerto
19.
JCI Insight ; 8(1)2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36625345

RESUMO

Substantial clinical evidence supports the notion that ciliary function in the airways is important in COVID-19 pathogenesis. Although ciliary damage has been observed in both in vitro and in vivo models, the extent or nature of impairment of mucociliary transport (MCT) in in vivo models remains unknown. We hypothesize that SARS-CoV-2 infection results in MCT deficiency in the airways of golden Syrian hamsters that precedes pathological injury in lung parenchyma. Micro-optical coherence tomography was used to quantitate functional changes in the MCT apparatus. Both genomic and subgenomic viral RNA pathological and physiological changes were monitored in parallel. We show that SARS-CoV-2 infection caused a 67% decrease in MCT rate as early as 2 days postinfection (dpi) in hamsters, principally due to 79% diminished airway coverage of motile cilia. Correlating quantitation of physiological, virological, and pathological changes reveals steadily descending infection from the upper airways to lower airways to lung parenchyma within 7 dpi. Our results indicate that functional deficits of the MCT apparatus are a key aspect of COVID-19 pathogenesis, may extend viral retention, and could pose a risk factor for secondary infection. Clinically, monitoring abnormal ciliated cell function may indicate disease progression. Therapies directed toward the MCT apparatus deserve further investigation.


Assuntos
COVID-19 , Animais , Cricetinae , COVID-19/patologia , Modelos Animais de Doenças , Progressão da Doença , Pulmão/diagnóstico por imagem , Pulmão/patologia , Mesocricetus , Depuração Mucociliar , SARS-CoV-2 , RNA Subgenômico
20.
J Stroke ; 25(1): 92-100, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36592969

RESUMO

BACKGROUND AND PURPOSE: High-grade carotid artery stenosis may alter hemodynamics in the ipsilateral hemisphere, but consequences of this effect are poorly understood. Cortical thinning is associated with cognitive impairment in dementia, head trauma, demyelination, and stroke. We hypothesized that hemodynamic impairment, as represented by a relative time-to-peak (TTP) delay on MRI in the hemisphere ipsilateral to the stenosis, would be associated with relative cortical thinning in that hemisphere. METHODS: We used baseline MRI data from the NINDS-funded Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis-Hemodynamics (CREST-H) study. Dynamic contrast susceptibility MR perfusion-weighted images were post-processed with quantitative perfusion maps using deconvolution of tissue and arterial signals. The protocol derived a hemispheric TTP delay, calculated by subtraction of voxel values in the hemisphere ipsilateral minus those contralateral to the stenosis. RESULTS: Among 110 consecutive patients enrolled in CREST-H to date, 45 (41%) had TTP delay of at least 0.5 seconds and 9 (8.3%) subjects had TTP delay of at least 2.0 seconds, the maximum delay measured. For every 0.25-second increase in TTP delay above 0.5 seconds, there was a 0.006-mm (6 micron) increase in cortical thickness asymmetry. Across the range of hemodynamic impairment, TTP delay independently predicted relative cortical thinning on the side of stenosis, adjusting for age, sex, hypertension, hemisphere, smoking history, low-density lipoprotein cholesterol, and preexisting infarction (P=0.032). CONCLUSIONS: Our findings suggest that hemodynamic impairment from high-grade asymptomatic carotid stenosis may structurally alter the cortex supplied by the stenotic carotid artery.

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