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1.
Clin Transl Immunology ; 13(5): e1507, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707997

RESUMO

Objectives: Autologous chimeric antigen receptor (CAR) T-cell therapy of B-cell malignancies achieves long-term disease remission in a high fraction of patients and has triggered intense research into translating this successful approach into additional cancer types. However, the complex logistics involved in autologous CAR-T manufacturing, the compromised fitness of patient-derived T cells, the high rates of serious toxicities and the overall cost involved with product manufacturing and hospitalisation have driven innovation to overcome such hurdles. One alternative approach is the use of allogeneic natural killer (NK) cells as a source for CAR-NK cell therapy. However, this source has traditionally faced numerous manufacturing challenges. Methods: To address this, we have developed an optimised expansion and transduction protocol for primary human NK cells primed for manufacturing scaling and clinical evaluation. We have performed an in-depth comparison of primary human NK cell sources as a starting material by characterising their phenotype, functionality, expansion potential and transduction efficiency at crucial timepoints of our CAR-NK manufacturing pipeline. Results: We identified adult peripheral blood-derived NK cells to be the superior source for generating a CAR-NK cell product because of a higher maximum yield of CAR-expressing NK cells combined with potent natural, as well as CAR-mediated anti-tumor effector functions. Conclusions: Our optimised manufacturing pipeline dramatically improves lentiviral transduction efficiency of primary human NK cells. We conclude that the exponential expansion pre- and post-transduction and high on-target cytotoxicity make peripheral blood-derived NK cells a feasible and attractive CAR-NK cell product for clinical utility.

2.
Proc Natl Acad Sci U S A ; 121(9): e2315985121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38377192

RESUMO

Recurrent, ancient arms races between viruses and hosts have shaped both host immunological defense strategies as well as viral countermeasures. One such battle is waged by the glycoprotein US11 encoded by the persisting human cytomegalovirus. US11 mediates degradation of major histocompatibility class I (MHC-I) molecules to prevent CD8+ T-cell activation. Here, we studied the consequences of the arms race between US11 and primate MHC-A proteins, leading us to uncover a tit-for-tat coevolution and its impact on MHC-A diversification. We found that US11 spurred MHC-A adaptation to evade viral antagonism: In an ancestor of great apes, the MHC-A A2 lineage acquired a Pro184Ala mutation, which confers resistance against the ancestral US11 targeting strategy. In response, US11 deployed a unique low-complexity region (LCR), which exploits the MHC-I peptide loading complex to target the MHC-A2 peptide-binding groove. In addition, the global spread of the human HLA-A*02 allelic family prompted US11 to employ a superior LCR strategy with an optimally fitting peptide mimetic that specifically antagonizes HLA-A*02. Thus, despite cytomegaloviruses low pathogenic potential, the increasing commitment of US11 to MHC-A has significantly promoted diversification of MHC-A in hominids.


Assuntos
Antígenos de Histocompatibilidade Classe I , Hominidae , Animais , Humanos , Proteínas Virais/metabolismo , Citomegalovirus , Hominidae/genética , Hominidae/metabolismo , Linhagem Celular , Antígenos de Histocompatibilidade/metabolismo , Antígenos HLA-A/metabolismo , Peptídeos/metabolismo
3.
J Clin Transl Sci ; 6(1): e45, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35651964

RESUMO

Background: Minority and older adult patients remain underrepresented in cancer clinical trials (CCTs). The current study sought to examine sociodemographic inequities in CCT interest, eligibility, enrollment, decline motivation, and attrition across two psychosocial CCTs for gynecologic, gastrointestinal, and thoracic cancers. Methods: Patients were approached for recruitment to one of two interventions: (1) a randomized control trial (RCT) examining effects of a cognitive-behavioral intervention targeting sleep, pain, mood, cytokines, and cortisol following surgery, or (2) a yoga intervention to determine its feasibility, acceptability, and effects on mitigating distress. Prospective RCT participants were queried about interest and screened for eligibility. All eligible patients across trials were offered enrollment. Patients who declined yoga intervention enrollment provided reasons for decline. Sociodemographic predictors of enrollment decisions and attrition were explored. Results: No sociodemographic differences in RCT interest were observed, and older patients were more likely to be ineligible. Eligible Hispanic patients across trials were significantly more likely to enroll than non-Hispanic patients. Sociodemographic factors predicted differences in decline motivation. In one trial, individuals originating from more urban areas were more likely to prematurely discontinue participation. Discussion: These results corroborate evidence of no significant differences in CCT interest across minority groups, with older adults less likely to fulfill eligibility criteria. While absolute Hispanic enrollment was modest, Hispanic patients were more likely to enroll relative to non-Hispanic patients. Additional sociodemographic trends were noted in decline motivation and geographical prediction of attrition. Further investigation is necessary to better understand inequities, barriers, and best recruitment practices for representative CCTs.

4.
ACS Mater Au ; 2(2): 176-189, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36855757

RESUMO

While the improvement of water-based adhesives with renewable additives is important as industry shifts toward more sustainable practices, a complete understanding of how the compatibility between additives and polymers affects adhesive performance is currently lacking. To elucidate these links, cellulose nanocrystals (CNCs) were first functionalized via surface-initiated atom-transfer radical polymerization with the hydrophobic polymers poly(butyl acrylate) (PBA) and poly(methyl methacrylate) (PMMA) to facilitate their incorporation into latex-based pressure-sensitive adhesives (PSAs). Next, PBA latexes were synthesized using seeded semibatch emulsion polymerization with unmodified or polymer-grafted CNCs added in situ at a loading of 0.5 or 1 phm (parts per hundred parts of monomer). Viscosity and electron microscopy suggested that the polymer-grafted CNCs were incorporated inside or on the latex particles. PSAs containing any CNC type had one or more improved properties (compared to the no-CNC "base case"); CNCs with a low degree of polymerization (DP) grafts exhibited improved tack (up to 2.5-fold higher) and peel strength (up to 6-fold higher) relative to PSAs with unmodified CNCs. The best performing PSA contained the low DP PMMA-grafted CNCs, which is attributed to the higher glass transition temperature and the higher wettability of the PMMA grafts compared to PBA, and the more uniform dispersion of polymer-grafted CNCs throughout the PSA film. In contrast, PSAs containing CNCs with high DP grafts resulted in reduced tack and peel strength (compared to low DP grafts) due to enhanced CNC aggregation. Unfortunately, all PSAs containing polymer-grafted CNCs exhibited inferior shear strength relative to PSAs with unmodified CNCs (and comparable shear strength to the no-CNC "base case"). Collectively, these results provide guidelines for future optimization of more sustainable latex-based PSAs.

5.
J Clin Sleep Med ; 18(1): 203-215, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34310276

RESUMO

STUDY OBJECTIVES: To examine whether cognitive behavioral treatments for insomnia (CBT-I) and pain (CBT-P) lead to neural activation changes in response to pain in fibromyalgia. METHODS: Thirty-two patients with fibromyalgia (mean age = 55.9, standard deviation = 12.2) underwent an experimental pain protocol during functional magnetic resonance imaging and completed 14-day diaries assessing total wake time, total sleep time, and pain intensity before and after CBT-I, CBT-P, or waitlist control. Random effects analysis of covariance identified regions with significant group (CBT-I, CBT-P, waitlist control) by time (baseline, post-treatment) interactions in blood oxygen level-dependent response to pain. Linear regressions using residualized change scores examined how changes in total wake time, total sleep time, and pain intensity were related to activation (blood oxygen level-dependent) changes. RESULTS: Twelve regions exhibited small to moderate effects with significant interactions Ps < .00; right hemisphere: inferior frontal, middle occipital, and superior temporal gyri, insula, lentiform nucleus; left hemisphere: angular, superior temporal, midfrontal, inferior occipital, midtemporal, and inferior frontal gyri. Blood oxygen level-dependent response to pain decreased in 8 regions following CBT-I, and in 3 regions following CBT-P (CBT-I effects > CBT-P). Blood oxygen level-dependent response also increased in 3 regions following CBT-P and in 6 regions following waitlist control. Improved total wake time and/or total sleep time, not pain intensity, predicted decreased blood oxygen level-dependence in 7 regions (Ps < .05), accounting for 18%-47% of the variance. CONCLUSIONS: CBT-I prompted greater decreases in neural activation in response to pain across more regions associated with pain and sleep processing than CBT-P. Reported sleep improvements may underlie those decreases. Future research examining the longer-term impact of CBT-I and improved sleep on central pain and sleep mechanisms is warranted. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Title: Sleep and Pain Interventions in Fibromyalgia (SPIN); Identifier: NCT02001077; URL: https://clinicaltrials.gov/ct2/show/NCT02001077. CITATION: McCrae CS, Craggs JG, Curtis AF, et al. Neural activation changes in response to pain following cognitive behavioral therapy for patients with comorbid fibromyalgia and insomnia: a pilot study. J Clin Sleep Med. 2022;18(1):203-215.


Assuntos
Terapia Cognitivo-Comportamental , Fibromialgia , Distúrbios do Início e da Manutenção do Sono , Fibromialgia/complicações , Fibromialgia/terapia , Humanos , Pessoa de Meia-Idade , Dor , Projetos Piloto , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/terapia , Resultado do Tratamento
6.
Behav Sleep Med ; 20(4): 460-476, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34124972

RESUMO

Insomnia is an adverse cancer outcome impacting mood, pain, quality of life, and mortality in cancer patients. Cognitive Behavioral Therapy (CBT) is an evidence-based treatment for diverse psychophysiological disorders, including pain and insomnia. Primarily studied in breast cancer, there is limited research on CBT within gynecology oncology. This study examined CBT effects on subjective and behavioral sleep outcomes: Sleep Efficiency (SE), Sleep Quality (SQ), Total Wake Time (TWT), Sleep Onset Latency (SOL), and Wake After Sleep Onset (WASO). Thirty-five women with insomnia status/post-surgery for gynecologic cancer were randomized to CBT for insomnia and pain (CBTi.p., N = 18) or Psychoeducation (N = 17). Sleep was assessed via sleep diaries and wrist-worn actigraphy at baseline (T1), post-intervention (T2), and two-month follow-up (T3). Intent-to-treat analyses utilizing mixed linear modeling examined longitudinal group differences on sleep controlling for age and advanced cancer. All participants demonstrated improved (1) subjective SE (0.5, p < .01), SOL (-1.2, p < .01), TWT (-1.2, p < .01), and (2) behavioral SE (0.1, p = .02), TWT (-1.2, p = .03), WASO (-0.8, p < .01) across time. Group-level time trends were indicative of higher subjective SE (6.8, p = .02), lower TWT (-40.3, p = .01), and lower SOL (-13.0, p = .05) in CBTi.p. compared to Psychoeducation. Supplemental analyses examining clinical significance and acute treatment effects demonstrated clinical improvements in SE (T1), TWT (T2, T3), and SOL (T3). Remaining effects were not significant. Despite lacking power to detect interaction effects, CBTi.p. clinically improved sleep in women with gynecologic cancers and insomnia during the active treatment phase. Future research will focus on developing larger trials within underserved populations.


Assuntos
Terapia Cognitivo-Comportamental , Neoplasias dos Genitais Femininos , Distúrbios do Início e da Manutenção do Sono , Feminino , Neoplasias dos Genitais Femininos/complicações , Neoplasias dos Genitais Femininos/terapia , Humanos , Dor , Qualidade de Vida , Sono , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/terapia , Resultado do Tratamento
7.
Proc Natl Acad Sci U S A ; 118(49)2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34845016

RESUMO

Unlike conventional αß T cells, γδ T cells typically recognize nonpeptide ligands independently of major histocompatibility complex (MHC) restriction. Accordingly, the γδ T cell receptor (TCR) can potentially recognize a wide array of ligands; however, few ligands have been described to date. While there is a growing appreciation of the molecular bases underpinning variable (V)δ1+ and Vδ2+ γδ TCR-mediated ligand recognition, the mode of Vδ3+ TCR ligand engagement is unknown. MHC class I-related protein, MR1, presents vitamin B metabolites to αß T cells known as mucosal-associated invariant T cells, diverse MR1-restricted T cells, and a subset of human γδ T cells. Here, we identify Vδ1/2- γδ T cells in the blood and duodenal biopsy specimens of children that showed metabolite-independent binding of MR1 tetramers. Characterization of one Vδ3Vγ8 TCR clone showed MR1 reactivity was independent of the presented antigen. Determination of two Vδ3Vγ8 TCR-MR1-antigen complex structures revealed a recognition mechanism by the Vδ3 TCR chain that mediated specific contacts to the side of the MR1 antigen-binding groove, representing a previously uncharacterized MR1 docking topology. The binding of the Vδ3+ TCR to MR1 did not involve contacts with the presented antigen, providing a basis for understanding its inherent MR1 autoreactivity. We provide molecular insight into antigen-independent recognition of MR1 by a Vδ3+ γδ TCR that strengthens an emerging paradigm of antibody-like ligand engagement by γδ TCRs.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Linfócitos Intraepiteliais/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Adulto , Apresentação de Antígeno , Feminino , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/fisiologia , Humanos , Linfócitos Intraepiteliais/fisiologia , Ligantes , Masculino , Antígenos de Histocompatibilidade Menor/química , Antígenos de Histocompatibilidade Menor/fisiologia , Células T Invariantes Associadas à Mucosa/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/fisiologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Receptores de Antígenos de Linfócitos T gama-delta/fisiologia
8.
Chest ; 160(5): e419-e425, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34339687

RESUMO

This document summarizes suggestions of the central sleep apnea (CSA) Technical Expert Panel working group. This paper shares our vision for bringing the right device to the right patient at the right time. For patients with CSA, current coverage criteria do not align with guideline treatment recommendations. For example, CPAP and oxygen therapy are recommended but not covered for CSA. On the other hand, bilevel positive airway pressure (BPAP) without a backup rate may be a covered therapy for OSA, but it may worsen CSA. Narrow coverage criteria that require near elimination of obstructive breathing events on CPAP or BPAP in the spontaneous mode, even if at poorly tolerated pressure levels, may preclude therapy with BPAP with backup rate or adaptive servoventilation, even when those devices provide demonstrably better therapy. CSA is a dynamic disorder that may require different treatments over time, sometimes switching from one device to another; an example is switching from BPAP with backup rate to an adaptive servoventilation with automatic end-expiratory pressure adjustments, which may not be covered. To address these challenges, we suggest several changes to the coverage determinations, including: (1) a single simplified initial and continuing coverage definition of CSA that aligns with OSA; (2) removal of hypoventilation terminology from coverage criteria for CSA; (3) all effective therapies for CSA should be covered, including oxygen and all PAP devices with or without backup rates or servo-mechanisms; and (4) patients shown to have a suboptimal response to one PAP device should be allowed to add oxygen or change to another PAP device with different capabilities if shown to be effective with testing.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas , Hipóxia , Medicare , Ventilação não Invasiva , Oxigenoterapia , Apneia do Sono Tipo Central , Pressão Positiva Contínua nas Vias Aéreas/instrumentação , Pressão Positiva Contínua nas Vias Aéreas/métodos , Humanos , Hipóxia/diagnóstico , Hipóxia/etiologia , Hipóxia/fisiopatologia , Hipóxia/terapia , Medicare/organização & administração , Medicare/normas , Ventilação não Invasiva/instrumentação , Ventilação não Invasiva/métodos , Oxigenoterapia/instrumentação , Oxigenoterapia/métodos , Seleção de Pacientes , Apneia do Sono Tipo Central/complicações , Apneia do Sono Tipo Central/fisiopatologia , Apneia do Sono Tipo Central/terapia , Tempo para o Tratamento , Estados Unidos
9.
Philos Trans A Math Phys Eng Sci ; 379(2206): 20200330, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34334024

RESUMO

Emulsion polymerized latex-based pressure-sensitive adhesives (PSAs) are more environmentally benign because they are synthesized in water but often underperform compared to their solution polymerized counterparts. Studies have shown a simultaneous improvement in the tack, and peel and shear strength of various acrylic PSAs upon the addition of cellulose nanocrystals (CNCs). This work uses atomic force microscopy (AFM) to examine the role of CNCs in (i) the coalescence of hydrophobic 2-ethyl hexyl acrylate/n-butyl acrylate/methyl methacrylate (EHA/BA/MMA) latex films and (ii) as adhesion modifiers over multiple length scales. Thin films with varying solids content and CNC loading were prepared by spin coating. AFM revealed that CNCs lowered the solids content threshold for latex particle coalescence during film formation. This improved the cohesive strength of the films, which was directly reflected in the increased shear strength of the EHA/BA/MMA PSAs with increasing CNC loading. Colloidal probe AFM indicated that the nano-adhesion of thicker continuous latex films increased with CNC loading when measured over small contact areas where the effect of surface roughness was negligible. Conversely, the beneficial effects of the CNCs on macroscopic PSA tack and peel strength were outweighed by the effects of increased surface roughness with increasing CNC loading over larger surface areas. This highlights that CNCs can improve both cohesive and adhesive PSA properties; however, the effects are most pronounced when the CNCs interact favourably with the latex polymer and are uniformly dispersed throughout the adhesive film. This article is part of the theme issue 'Bio-derived and bioinspired sustainable advanced materials for emerging technologies (part 1)'.


Assuntos
Celulose , Nanopartículas , Adesivos , Interações Hidrofóbicas e Hidrofílicas , Polimerização
10.
Sleep Med ; 80: 286-293, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33610076

RESUMO

INTRODUCTION: Brief (≤4 sessions) behavioral treatment for insomnia (BBTi) improves insomnia symptoms in older adults. Findings for BBTi-related improvements in objective cognition are mixed, with our recent trial reporting no effects. Metacognition (appraisal of one's own performance) has not been examined. This study examined the effects of BBTi on metacognition in older adults with insomnia. METHODS: Older adults with insomnia [N = 62, Mage = 69.45 (SD = 7.71)] were randomized to 4-weeks of BBTi (n = 32; psychoeducation, sleep hygiene, stimulus control, sleep restriction, relaxation, review/maintenance) or self-monitoring control (SMC; n = 30; social conversations). Throughout the study (2 week baseline, 4 week treatment, 2 week post-treament, 2 week 3-month followup), participants completed daily paper/pencil cognitive tasks (measuring verbal memory, attention, processing speed and reasoning) and provided daily metacognition ratings of their performance in four areas: quality, satisfaction, compared to same age peers, compared to own ability. Two-week averages of metacognitive ratings were calculated for baseline, treatment-first half, treatment-second half, post-treatment, and 3-month follow-up. Multilevel Modeling examined treatment effects (BBTi/SMC) over time on metacognition, controlling for age and sex. RESULTS: A significant group by time interaction (p = 0.05) revealed consistent improvements over time in better metacognitive ratings relative to same age peers for BBTi. Specifically, baseline ratings [mean (M) = 51.21, standard error (SE) = 3.15] improved at first half of treatment (M = 56.65, SE = 3.15, p < 0.001), maintained improvement at second-half of treatment (p = 0.18), showed additional improvement at post-treatment (M = 60.79, SE = 3.15, p = 0.02), and maintained improvement at follow-up (M = 62.30, SE = 3.15; p = 0.02). SMC prompted inconsistent and smaller improvements between baseline (M = 53.24, SE = 3.29) and first-half of treatment (M = 56.62, SE = 3.28; p = 0.004), with additional improvement at second-half of treatment (M = 59.39, SE = 3.28; p = 0.02) that was maintained at post-treatment (p = 0.73) and returned to levels observed at first-half of treatment (M = 57.78, SE = 3.21; p = 0.55). Significant main effects of time (all ps < 0.001) for other metacognition variables (Quality, Satisfaction, Compared to own ability) indicated general improvements over time for both groups. DISCUSSION: Metacognition generally improved over time regardless of treatment. BBTi selectively improved ratings of performance relative to same age peers. Repeated objective testing alone may improve metacognition in older adults with insomnia. Better understanding of metacognition and how to improve it has important implications for older adults as metacognitive complaints have been associated with mild cognitive impairment.


Assuntos
Metacognição , Distúrbios do Início e da Manutenção do Sono , Idoso , Terapia Comportamental , Humanos , Pessoa de Meia-Idade , Sono , Distúrbios do Início e da Manutenção do Sono/terapia , Resultado do Tratamento
11.
Macromol Rapid Commun ; 42(3): e2000448, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33047439

RESUMO

Cellulose nanocrystals (CNCs), a sustainable nanomaterial, are in situ incorporated into emulsion-based pressure-sensitive adhesives (PSAs). Commercially available CNCs with different surface hydrophilicity and surface charge (CNC101 and CNC103 from CelluForce) are used to explore their role in PSA property modification. Viscosity measurements and atomic force microscopy reveal differences in degree of association between the CNCs and the latex particles depending on the surface properties of the CNCs. The more hydrophilic and higher surface charge CNCs (CNC101) show less association with the latex particles. Dynamic strain sweep tests are used to analyze the strain-softening of the nanocomposites based on CNC type and loading. The CNC101 nanocomposites soften at lower strains than their CNC103 counterparts. This behavior is confirmed via dynamic frequency tests and modeling of the nanocomposites' storage moduli, which suggest the formation of CNC aggregates of, on average, 3.8 CNC101 and 1.3 CNC103 nanoparticles. Finally, PSA properties, i.e., tack, peel strength, and shear strength, simultaneously increase upon addition of both CNC types, although to different extents. The relationship between the PSA properties and CNC surface properties confirms that the less hydrophilic CNCs lead to improved CNC dispersion in the PSA films and therefore, enhance PSA properties.


Assuntos
Nanocompostos , Nanopartículas , Adesivos , Celulose , Interações Hidrofóbicas e Hidrofílicas
12.
J Biol Chem ; 296: 100127, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33257321

RESUMO

DEC-205 (CD205), a member of the macrophage mannose receptor protein family, is the prototypic endocytic receptor of dendritic cells, whose ligands include phosphorothioated cytosine-guanosine oligonucleotides, a motif often seen in bacterial or viral DNA. However, despite growing biological and clinical significance, little is known about the structural arrangement of this receptor or any of its family members. Here, we describe the 3.2 Å cryo-EM structure of human DEC-205, thereby illuminating the structure of the mannose receptor protein family. The DEC-205 monomer forms a compact structure comprising two intercalated rings of C-type lectin-like domains, where the N-terminal cysteine-rich and fibronectin domains reside at the central intersection. We establish a pH-dependent oligomerization pathway forming tetrameric DEC-205 using solution-based techniques and ultimately solved the 4.9 Å cryo-EM structure of the DEC-205 tetramer to identify the unfurling of the second lectin ring which enables tetramer formation. Furthermore, we suggest the relevance of this oligomerization pathway within a cellular setting, whereby cytosine-guanosine binding appeared to disrupt this cell-surface oligomer. Accordingly, we provide insight into the structure and oligomeric assembly of the DEC-205 receptor.


Assuntos
Antígenos CD/química , Antígenos CD/metabolismo , Microscopia Crioeletrônica/métodos , Fibronectinas/metabolismo , Lectinas Tipo C/metabolismo , Antígenos de Histocompatibilidade Menor/química , Antígenos de Histocompatibilidade Menor/metabolismo , Receptores de Superfície Celular/química , Receptores de Superfície Celular/metabolismo , Humanos , Lectinas Tipo C/química , Ligantes , Conformação Proteica
13.
Southwest J Pulm Crit Care ; 21(4): 86-103, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163289

RESUMO

BACKGROUND: Studies have established that OSA defined using a hypopnea definition requiring a ≥4% oxygen desaturation (AHI4%) is associated with cardiovascular (CVD) or coronary heart (CHD) disease. This study determined whether OSA defined using a hypopnea definition characterized by a ≥3% oxygen desaturation or an arousal (AHI3%A) is associated with CVD/CHD. METHODS: Data were analyzed from 6307 Sleep Heart Health Study participants who had polysomnography. Self-reported CVD included angina, heart attack, heart failure, stroke, previous coronary bypass surgery or angioplasty. Self-reported CHD included the aforementioned conditions but not stroke or heart failure. The association between OSA and CVD/CHD was examined using logistic regression models with stepwise inclusion of demographic, anthropometric, social/behavioral and co-morbid medical conditions. A parsimonious model in which diabetes and hypertension were excluded because of their potential to be on the causal pathway between OSA and CVD/CHD also was constructed. RESULTS: For CVD, the odds ratios and 95% confidence intervals for AHI3%A ≥30/hour were 1.39 (1.03-1.87) and 1.45 (1.09-1.94) in the fully adjusted and parsimonious models. Results for CHD were 1.29 (0.96-1.74) and 1.36 (0.99-1.85). In participants without OSA according to more stringent AHI4% criteria but with OSA using the AHI3%A definition, similar findings were observed. CONCLUSION: OSA defined using an AHI3%A is associated with both CVD and CHD. Use of a more restrictive AHI4% definition will misidentify a large number of individuals with OSA who have CVD or CHD. These individuals may be denied access to therapy, potentially worsening their underlying CVD or CHD.

14.
Proc Natl Acad Sci U S A ; 117(43): 26766-26772, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33051299

RESUMO

Archaea swim using the archaellum (archaeal flagellum), a reversible rotary motor consisting of a torque-generating motor and a helical filament, which acts as a propeller. Unlike the bacterial flagellar motor (BFM), ATP (adenosine-5'-triphosphate) hydrolysis probably drives both motor rotation and filamentous assembly in the archaellum. However, direct evidence is still lacking due to the lack of a versatile model system. Here, we present a membrane-permeabilized ghost system that enables the manipulation of intracellular contents, analogous to the triton model in eukaryotic flagella and gliding Mycoplasma We observed high nucleotide selectivity for ATP driving motor rotation, negative cooperativity in ATP hydrolysis, and the energetic requirement for at least 12 ATP molecules to be hydrolyzed per revolution of the motor. The response regulator CheY increased motor switching from counterclockwise (CCW) to clockwise (CW) rotation. Finally, we constructed the torque-speed curve at various [ATP]s and discuss rotary models in which the archaellum has characteristics of both the BFM and F1-ATPase. Because archaea share similar cell division and chemotaxis machinery with other domains of life, our ghost model will be an important tool for the exploration of the universality, diversity, and evolution of biomolecular machinery.


Assuntos
Membrana Celular , Quimiotaxia/fisiologia , Haloferax volcanii , Modelos Biológicos , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas Arqueais/química , Proteínas Arqueais/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular , Flagelos/química , Flagelos/metabolismo , Haloferax volcanii/citologia , Haloferax volcanii/metabolismo , Cinética , Proteínas Quimiotáticas Aceptoras de Metil/química , Proteínas Quimiotáticas Aceptoras de Metil/metabolismo , Proteínas Motores Moleculares/química , Proteínas Motores Moleculares/metabolismo
15.
J Immunol ; 205(6): 1709-1717, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32817368

RESUMO

The generation of reliable mAb of unique and desired specificities serves as a valuable technology to study protein expression and function. However, standard approaches to mAb generation usually involve large-scale protein purification and intensive screening. In this study, we describe an optimized high-throughput proof-of-principle method for the expanded generation, enrichment, and screening of mouse hybridomas secreting mAb specific for a protein of interest. Briefly, we demonstrate that small amounts of a biotinylated protein of interest can be used to generate tetramers for use as prime-boost immunogens, followed by selective enrichment of Ag-specific B cells by magnetic sorting using the same tetramers prior to hybridoma generation. This serves two purposes: 1) to effectively expand both low- and high-affinity B cells specific for the antigenic bait during immunization and 2) to minimize subsequent laborious hybridoma efforts by positive selection of Ag-specific, Ab-secreting cells prior to hybridoma fusion and validation screening. Finally, we employ a rapid and inexpensive screening technology, CELLISA, a high-throughput validation method that uses a chimeric Ag fused to the CD3ζ signaling domain expressed on enzyme-generating reporter cells; these reporters can detect specific mAb in hybridoma supernatants via plate-bound Ab-capture arrays, thereby easing screening. Using this strategy, we generated and characterized novel mouse mAb specific for a viral immunoevasin, the mouse CMV m12 protein, and suggest that these mAb may protect mice from CMV infection via passive immunity.


Assuntos
Anticorpos Monoclonais/isolamento & purificação , Infecções por Herpesviridae/imunologia , Ensaios de Triagem em Larga Escala/métodos , Muromegalovirus/metabolismo , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Monoclonais/metabolismo , Linfócitos B/imunologia , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Hibridomas , Evasão da Resposta Imune , Imunização , Camundongos , Multimerização Proteica , Vacinação
16.
Int J Biol Macromol ; 164: 2038-2050, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32739512

RESUMO

In this study, the effect of cellulose nanocrystals (CNCs) incorporation on the structure-properties of acrylonitrile-butadiene rubber (NBR films), with particular focus on curing enhancement and reinforcing potential, was investigated. The NBR crosslinking efficiency, observed from nuclear magnetic resonance analysis, increased with successive CNC concentration increases due to better dispersion of ZnO from Zn-cellulose complex formation. Energy dispersive X-ray and transmission electron microscope analysis of the films revealed increasingly well-dispersed ZnO with increasing CNC. The increase in the crosslinking density in conjuncture with the reinforcing capability of CNCs resulted in increases in the tensile strength, stiffness, toughness, tear strength and elongation by 203, 8300, 664, 179, and 14%, respectively for films containing 3 phr CNC compared to the neat NBR. The incorporation of 0.5 phr CNC reduced the water absorption of neat CNC by 250%. Overall, water absorption of the nanocomposite films was considerably lower than that of the neat NBR through CNC consolidation of the rubber particles by reducing free volume in the NBR structure. The nanocomposite films show promise for glove and other dipped product applications where improved tear resistance and overall physical properties improvement are needed without compromising the integrity.


Assuntos
Acrilonitrila/química , Butadienos/química , Celulose/química , Nanopartículas/química , Borracha/química , Água/química , Nanocompostos/química , Resistência à Tração , Óxido de Zinco/química
17.
Sleep Med Clin ; 15(2): 219-225, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32386696

RESUMO

Patient interface preference is a key factor in positive airway pressure compliance. Local side effects are common. Proper mask fitting and patient education are important. Masks should seal well and fit comfortably. Nasal, nasal pillow, and oronasal masks can be effective interfaces. Most patients with obstructive sleep apnea prefer a nasal mask. Oronasal masks can be a useful alternative. Nasal pillows can reduce mask size and improve comfort. Oronasal masks may require a higher pressure. A significantly lower pressure may be effective with a nasal interface. Proper mask fitting requires testing the mask seal under the treatment pressure.


Assuntos
Máscaras , Cooperação do Paciente , Respiração com Pressão Positiva/instrumentação , Apneia Obstrutiva do Sono/terapia , Humanos
18.
Nat Commun ; 11(1): 2615, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457314

RESUMO

F1Fo ATP synthase functions as a biological rotary generator that makes a major contribution to cellular energy production. It comprises two molecular motors coupled together by a central and a peripheral stalk. Proton flow through the Fo motor generates rotation of the central stalk, inducing conformational changes in the F1 motor that catalyzes ATP production. Here we present nine cryo-EM structures of E. coli ATP synthase to 3.1-3.4 Å resolution, in four discrete rotational sub-states, which provide a comprehensive structural model for this widely studied bacterial molecular machine. We observe torsional flexing of the entire complex and a rotational sub-step of Fo associated with long-range conformational changes that indicates how this flexibility accommodates the mismatch between the 3- and 10-fold symmetries of the F1 and Fo motors. We also identify density likely corresponding to lipid molecules that may contribute to the rotor/stator interaction within the Fo motor.


Assuntos
Proteínas de Escherichia coli/química , ATPases Translocadoras de Prótons/química , Difosfato de Adenosina/metabolismo , Microscopia Crioeletrônica , Proteínas de Escherichia coli/metabolismo , Lipídeos/química , Modelos Moleculares , Conformação Proteica , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Rotação , Relação Estrutura-Atividade
19.
J Sleep Res ; 29(6): e13020, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32126156

RESUMO

Sleep and opioid medications used to treat insomnia and chronic pain are associated with adverse side effects (falls and cognitive disturbance). Although behavioural treatments such as cognitive behavioral therapy for insomnia (CBT-I) and pain (CBT-P) improve sleep and clinical pain, their effects on sleep and opioid medication use are unclear. In this secondary analysis of published trial data, we investigated whether CBT-I and CBT-P reduced reliance on sleep/opioid medication in patients with fibromyalgia and insomnia (FMI). Patients with FMI (n = 113, Mage  = 53.0, SD = 10.9) completed 8 weeks of CBT-I (n = 39), CBT-P (n = 37) or waitlist control (WLC; n = 37). Participants completed 14 daily diaries at baseline, post-treatment and 6-month follow-up, assessing sleep and opioid medication usage. Multilevel modelling examined group by time effects on days of medication use. A significant interaction revealed CBT-P reduced the number of days of sleep medication use at post-treatment, but usage returned to baseline levels at follow-up. There were no other significant within- or between-group effects. CBT-P led to immediate reductions in sleep medication usage, despite lack of explicit content regarding sleep medication. CBT-I and CBT-P may be ineffective as stand-alone treatments for altering opioid use in FMI. Future work should explore CBT as an adjunct to other behavioural techniques for opioid reduction.


Assuntos
Analgésicos Opioides/uso terapêutico , Terapia Cognitivo-Comportamental/métodos , Fibromialgia/terapia , Distúrbios do Início e da Manutenção do Sono/terapia , Feminino , Fibromialgia/psicologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
20.
J Sleep Res ; 29(4): e12981, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31912641

RESUMO

The prevalence and correlates of sleep apnea (SA) among Veterans with chronic kidney disease (CKD), a population at high risk of both SA and CKD, are unknown. We performed a cross-sectional analysis of 248 Veterans (18-89 years) selected only for presence of moderate to severe CKD. All participants underwent full, unattended polysomnography, measurement of renal function and a sleepiness questionnaire. Logistic regression with backward selection was used to identify predictors of prevalent SA (apnea-hypopnea index [AHI, ≥15 events/hr] and prevalent nocturnal hypoxia [NH, % of total sleep time spent at <90% oxygen saturation]). The mean age of our cohort was 73.2 ± 9.6 years, 95% were male, 78% were Caucasian and the mean body mass index (BMI) was 30.3 ± 4.8 kg/m2 . The prevalence of SA was 39%. There was no difference in daytime sleepiness among those with and without SA. In the final model, older age, higher BMI and diabetes mellitus (DM) were associated with higher odds of SA, after controlling for age, BMI, race and sex. Higher BMI, DM, unemployed/retired status, current smoking and higher serum bicarbonate level were associated with prevalent NH. To sum, SA was common among Veterans with moderate to severe CKD. Although some traditional risk factors for SA were associated with SA in this population, sleepiness did not correlate with SA. Further study is needed to validate our findings and understand how best to address the high burden of SA among Veterans with CKD.


Assuntos
Polissonografia/métodos , Insuficiência Renal Crônica/epidemiologia , Síndromes da Apneia do Sono/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco , Inquéritos e Questionários , Veteranos , Adulto Jovem
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