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1.
Nat Immunol ; 22(12): 1503-1514, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34716452

RESUMO

Prevention of viral escape and increased coverage against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern require therapeutic monoclonal antibodies (mAbs) targeting multiple sites of vulnerability on the coronavirus spike glycoprotein. Here we identify several potent neutralizing antibodies directed against either the N-terminal domain (NTD) or the receptor-binding domain (RBD) of the spike protein. Administered in combinations, these mAbs provided low-dose protection against SARS-CoV-2 infection in the K18-human angiotensin-converting enzyme 2 mouse model, using both neutralization and Fc effector antibody functions. The RBD mAb WRAIR-2125, which targets residue F486 through a unique heavy-chain and light-chain pairing, demonstrated potent neutralizing activity against all major SARS-CoV-2 variants of concern. In combination with NTD and other RBD mAbs, WRAIR-2125 also prevented viral escape. These data demonstrate that NTD/RBD mAb combinations confer potent protection, likely leveraging complementary mechanisms of viral inactivation and clearance.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/metabolismo , Sítios de Ligação/genética , COVID-19/metabolismo , COVID-19/prevenção & controle , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Mapeamento de Epitopos , Epitopos/química , Epitopos/imunologia , Epitopos/metabolismo , Humanos , Camundongos Transgênicos , Testes de Neutralização , Ligação Proteica , Conformação Proteica , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Homologia de Sequência de Aminoácidos , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Análise de Sobrevida
2.
Proc Natl Acad Sci U S A ; 121(21): e2402540121, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38758698

RESUMO

All respiratory viruses establish primary infections in the nasal epithelium, where efficient innate immune induction may prevent dissemination to the lower airway and thus minimize pathogenesis. Human coronaviruses (HCoVs) cause a range of pathologies, but the host and viral determinants of disease during common cold versus lethal HCoV infections are poorly understood. We model the initial site of infection using primary nasal epithelial cells cultured at an air-liquid interface (ALI). HCoV-229E, HCoV-NL63, and human rhinovirus-16 are common cold-associated viruses that exhibit unique features in this model: early induction of antiviral interferon (IFN) signaling, IFN-mediated viral clearance, and preferential replication at nasal airway temperature (33 °C) which confers muted host IFN responses. In contrast, lethal SARS-CoV-2 and MERS-CoV encode antagonist proteins that prevent IFN-mediated clearance in nasal cultures. Our study identifies features shared among common cold-associated viruses, highlighting nasal innate immune responses as predictive of infection outcomes and nasally directed IFNs as potential therapeutics.


Assuntos
Resfriado Comum , Imunidade Inata , Interferons , Mucosa Nasal , SARS-CoV-2 , Transdução de Sinais , Humanos , Mucosa Nasal/virologia , Mucosa Nasal/imunologia , Mucosa Nasal/metabolismo , Interferons/metabolismo , Interferons/imunologia , Resfriado Comum/imunologia , Resfriado Comum/virologia , Transdução de Sinais/imunologia , SARS-CoV-2/imunologia , Replicação Viral , Rhinovirus/imunologia , Coronavirus Humano 229E/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Células Epiteliais/virologia , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Coronavirus Humano NL63/imunologia
3.
Proc Natl Acad Sci U S A ; 121(15): e2320194121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38568967

RESUMO

Severe acute respiratory syndrome coronavirus (SARS-CoV)-2 has caused millions of deaths since its emergence in 2019. Innate immune antagonism by lethal CoVs such as SARS-CoV-2 is crucial for optimal replication and pathogenesis. The conserved nonstructural protein 15 (nsp15) endoribonuclease (EndoU) limits activation of double-stranded (ds)RNA-induced pathways, including interferon (IFN) signaling, protein kinase R (PKR), and oligoadenylate synthetase/ribonuclease L (OAS/RNase L) during diverse CoV infections including murine coronavirus and Middle East respiratory syndrome (MERS)-CoV. To determine how nsp15 functions during SARS-CoV-2 infection, we constructed a recombinant SARS-CoV-2 (nsp15mut) expressing catalytically inactivated nsp15, which we show promoted increased dsRNA accumulation. Infection with SARS-CoV-2 nsp15mut led to increased activation of the IFN signaling and PKR pathways in lung-derived epithelial cell lines and primary nasal epithelial air-liquid interface (ALI) cultures as well as significant attenuation of replication in ALI cultures compared to wild-type virus. This replication defect was rescued when IFN signaling was inhibited with the Janus activated kinase (JAK) inhibitor ruxolitinib. Finally, to assess nsp15 function in the context of minimal (MERS-CoV) or moderate (SARS-CoV-2) innate immune induction, we compared infections with SARS-CoV-2 nsp15mut and previously described MERS-CoV nsp15 mutants. Inactivation of nsp15 had a more dramatic impact on MERS-CoV replication than SARS-CoV-2 in both Calu3 cells and nasal ALI cultures suggesting that SARS-CoV-2 can better tolerate innate immune responses. Taken together, SARS-CoV-2 nsp15 is a potent inhibitor of dsRNA-induced innate immune response and its antagonism of IFN signaling is necessary for optimal viral replication in primary nasal ALI cultures.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Camundongos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Endorribonucleases/metabolismo , Transdução de Sinais , Antivirais
4.
Development ; 150(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37997694

RESUMO

Identification of signaling events that contribute to innate spinal cord regeneration in zebrafish can uncover new targets for modulating injury responses of the mammalian central nervous system. Using a chemical screen, we identify JNK signaling as a necessary regulator of glial cell cycling and tissue bridging during spinal cord regeneration in larval zebrafish. With a kinase translocation reporter, we visualize and quantify JNK signaling dynamics at single-cell resolution in glial cell populations in developing larvae and during injury-induced regeneration. Glial JNK signaling is patterned in time and space during development and regeneration, decreasing globally as the tissue matures and increasing in the rostral cord stump upon transection injury. Thus, dynamic and regional regulation of JNK signaling help to direct glial cell behaviors during innate spinal cord regeneration.


Assuntos
Traumatismos da Medula Espinal , Regeneração da Medula Espinal , Animais , Larva , Mamíferos , Regeneração Nervosa/fisiologia , Neuroglia/fisiologia , Medula Espinal , Peixe-Zebra/fisiologia , Proteínas Quinases JNK Ativadas por Mitógeno
5.
Proc Natl Acad Sci U S A ; 120(15): e2218083120, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37023127

RESUMO

The nasal epithelium is the initial entry portal and primary barrier to infection by all human coronaviruses (HCoVs). We utilize primary human nasal epithelial cells grown at air-liquid interface, which recapitulate the heterogeneous cellular population as well as mucociliary clearance functions of the in vivo nasal epithelium, to compare lethal [Severe acute respiratory syndrome (SARS)-CoV-2 and Middle East respiratory syndrome-CoV (MERS-CoV)] and seasonal (HCoV-NL63 and HCoV-229E) HCoVs. All four HCoVs replicate productively in nasal cultures, though replication is differentially modulated by temperature. Infections conducted at 33 °C vs. 37 °C (reflective of temperatures in the upper and lower airway, respectively) revealed that replication of both seasonal HCoVs (HCoV-NL63 and -229E) is significantly attenuated at 37 °C. In contrast, SARS-CoV-2 and MERS-CoV replicate at both temperatures, though SARS-CoV-2 replication is enhanced at 33 °C late in infection. These HCoVs also diverge significantly in terms of cytotoxicity induced following infection, as the seasonal HCoVs as well as SARS-CoV-2 cause cellular cytotoxicity as well as epithelial barrier disruption, while MERS-CoV does not. Treatment of nasal cultures with type 2 cytokine IL-13 to mimic asthmatic airways differentially impacts HCoV receptor availability as well as replication. MERS-CoV receptor DPP4 expression increases with IL-13 treatment, whereas ACE2, the receptor used by SARS-CoV-2 and HCoV-NL63, is down-regulated. IL-13 treatment enhances MERS-CoV and HCoV-229E replication but reduces that of SARS-CoV-2 and HCoV-NL63, reflecting the impact of IL-13 on HCoV receptor availability. This study highlights diversity among HCoVs during infection of the nasal epithelium, which is likely to influence downstream infection outcomes such as disease severity and transmissibility.


Assuntos
COVID-19 , Coronaviridae , Coronavirus Humano 229E , Humanos , Interleucina-13/metabolismo , Estações do Ano , SARS-CoV-2 , Células Epiteliais
6.
Proc Natl Acad Sci U S A ; 119(21): e2123208119, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35594398

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) emerged into humans in 2012, causing highly lethal respiratory disease. The severity of disease may be, in part, because MERS-CoV is adept at antagonizing early innate immune pathways­interferon (IFN) production and signaling, protein kinase R (PKR), and oligoadenylate synthetase/ribonuclease L (OAS/RNase L)­activated in response to viral double-stranded RNA (dsRNA) generated during genome replication. This is in contrast to severe acute respiratory syndrome CoV-2 (SARS-CoV-2), which we recently reported to activate PKR and RNase L and, to some extent, IFN signaling. We previously found that MERS-CoV accessory proteins NS4a (dsRNA binding protein) and NS4b (phosphodiesterase) could weakly suppress these pathways, but ablation of each had minimal effect on virus replication. Here we investigated the antagonist effects of the conserved coronavirus endoribonuclease (EndoU), in combination with NS4a or NS4b. Inactivation of EndoU catalytic activity alone in a recombinant MERS-CoV caused little if any effect on activation of the innate immune pathways during infection. However, infection with recombinant viruses containing combined mutations with inactivation of EndoU and deletion of NS4a or inactivation of the NS4b phosphodiesterase promoted robust activation of dsRNA-induced innate immune pathways. This resulted in at least tenfold attenuation of replication in human lung­derived A549 and primary nasal cells. Furthermore, replication of these recombinant viruses could be rescued to the level of wild-type MERS-CoV by knockout of host immune mediators MAVS, PKR, or RNase L. Thus, EndoU and accessory proteins NS4a and NS4b together suppress dsRNA-induced innate immunity during MERS-CoV infection in order to optimize viral replication.


Assuntos
COVID-19 , Infecções por Coronavirus , Coronavírus da Síndrome Respiratória do Oriente Médio , Infecções por Coronavirus/imunologia , Endorribonucleases/genética , Endorribonucleases/metabolismo , Células Epiteliais/metabolismo , Humanos , Imunidade Inata , Pulmão/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Mucosa Nasal , SARS-CoV-2/patogenicidade , Endorribonucleases Específicas de Uridilato
7.
J Vasc Surg ; 79(1): 62-70, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37683767

RESUMO

OBJECTIVE: Carotid web (CaWeb) is a rare form of fibromuscular dysplasia that can produce embolic stroke. Misdiagnosis of symptomatic CaWeb as "cryptogenic stroke" or "embolic stroke of unknown source" is common and can lead to recurrent, catastrophic neurologic events. Reports of CaWeb in the literature are scarce, and their natural history is poorly understood. Appropriate management remains controversial. METHODS: CaWeb was defined as a single, shelf-like, linear projection in the posterolateral carotid bulb causing a filling defect on computed tomography angiography (CTA) or cerebral angiography. Cases of symptomatic CaWeb at a single institution with a high-volume stroke center were identified through collaborative evaluation by vascular neurologists and vascular surgeons. RESULTS: Fifty-two patients with symptomatic CaWeb were identified during a 6-year period (2016-2022). Average age was 49 years (range, 29-73 years), 35 of 52 (67%) were African American, and 18 of 52 (35%) were African American women under age 50. Patients initially presented with stroke (47/52; 90%) or transient ischemic attack (5/52; 10%). Stenosis was <50% in 49 of 52 patients (94%) based on NASCET criteria, and 0 of 52 (0%) CaWebs were identified with carotid duplex. Definitive diagnosis was made by CTA examined in multiple planes or cerebral angiography examined in a lateral projection to adequately assess the posterolateral carotid bulb, where 52 of 52 (100%) of CaWebs were seen. Early in our institutional experience, 10 of 52 patients (19%) with symptomatic CaWeb were managed initially with dual antiplatelet and statin therapy or systemic anticoagulation; all suffered ipsilateral recurrent stroke at an average interval of 43 months (range, 1-89 months), and five were left with permanent deficits. Definitive treatment included carotid endarterectomy in 27 of 50 (56%) or carotid stenting in 23 of 50 (46%). Two strokes were irrecoverable, and intervention was deferred. Web-associated thrombus was observed in 20 of 50 (40%) on angiography or grossly upon carotid exploration. Average interval from initial stroke to intervention was 39 days. After an average follow-up of 38 months, there was no reported postintervention stroke or mortality. CONCLUSIONS: To our knowledge, this is the largest single-institution analysis of symptomatic CaWeb yet reported. Our series demonstrates that carotid duplex is inadequate for diagnosis, and that medical management is unacceptable for symptomatic CaWeb. Recurrent stroke occurred in all patients managed early in our experience with medical therapy alone. We have since adopted an aggressive interventional approach in cases of symptomatic CaWeb, with no postoperative stroke reported over an average follow-up of 38 months. In younger patients presenting with cryptogenic stroke, especially African American women, detailed review of lateral cerebral angiography or multi-planar, fine-cut CTA images is required to accurately rule out or diagnose CaWeb and avoid recurrent neurologic events.


Assuntos
Estenose das Carótidas , AVC Embólico , Endarterectomia das Carótidas , Ataque Isquêmico Transitório , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Estenose das Carótidas/cirurgia , Artérias Carótidas , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/etiologia , Endarterectomia das Carótidas/efeitos adversos
8.
J Vasc Surg ; 79(1): 3-10, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37734569

RESUMO

OBJECTIVE: Complex endovascular juxta-, para- and suprarenal abdominal aortic aneurysm repair (comEVAR) is frequently accomplished with commercially available fenestrated (FEVAR) devices or off-label use of aortoiliac devices with parallel branch stents (chEVAR). We sought to evaluate the implantable vascular device costs incurred with these procedures as compared with standard Medicare reimbursement to determine the financial viability of comEVAR in the modern era. METHODS: Five geographically distinct institutions with high-volume, complex aortic centers were included. Implantable aortoiliac and branch stent device cost data from 25 consecutive, recent, comEVAR in the treatment of juxta-, para-, and suprarenal aortic aneurysms at each center were analyzed. Cases of rupture, thoracic aneurysms, reinterventions, and physician-modified EVAR were excluded, as were ancillary costs from nonimplantable equipment. Data from all institutions were combined and stratified into an overall cost group and two, individual cost groups: FEVAR or chEVAR. These groups were compared, and each respective group was then compared with weighted Medicare reimbursement for Diagnosis-Related Group codes 268/269. Median device costs were obtained from an independent purchasing consortium of >3000 medical centers, yielding true median cost-to-institution data rather than speculative, administrative projections or estimates. RESULTS: A total of 125 cases were analyzed: 70 FEVAR and 53 chEVAR. Two cases of combined FEVAR/chEVAR were included in total cost analysis, but excluded from direct FEVAR vs chEVAR comparison. Median Medicare reimbursement was calculated as $35,755 per case. Combined average implantable device cost for all analyzed cases was $28,470 per case, or 80% of the median reimbursement ($28,470/$35,755). Average FEVAR device cost per case ($26,499) was significantly lower than average chEVAR cost per case ($32,122; P < .002). Device cost was 74% ($26,499/$35,755) of total reimbursement for FEVAR and 90% ($32,122/$35,755) for chEVAR. CONCLUSIONS: Results from this multi-institutional analysis show that implantable device cost alone represents the vast majority of weighted total Medicare reimbursement per case with comEVAR, and that chEVAR is significantly more costly than FEVAR. Inadequate Medicare reimbursement for these cases puts high-volume, high-complexity aortic centers at a distinct financial disadvantage. In the interest of optimizing patient care, these data suggest a reconsideration of previously established, outdated, Diagnosis-Related Group coding and Medicare reimbursement for comEVAR.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Idoso , Humanos , Estados Unidos , Correção Endovascular de Aneurisma , Prótese Vascular , Aneurisma da Aorta Abdominal/cirurgia , Fatores de Risco , Resultado do Tratamento , Medicare , Stents , Custos Hospitalares , Estudos Retrospectivos , Desenho de Prótese
9.
Langmuir ; 40(13): 6654-6665, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38457278

RESUMO

Charged colloidal particles neutralized by a single counterion are increasingly important for many emerging technologies. Attention here is paid specifically to hydrogen fuel cells and water electrolyzers whose catalyst layers are manufactured from a perfluorinated sulfonic acid polymer (PFSA) suspended in aqueous/alcohol solutions. Partially dissolved PFSA aggregates, known collectively as ionomers, are stabilized by the electrostatic repulsion of overlapping diffuse double layers consisting of only protons dissociated from the suspended polymer. We denote such double layers containing no added electrolyte as "single ion". Size-distribution predictions build upon interparticle interaction potential energies from the Derjaguin-Landau-Verwey-Overbeek (DLVO) formalism. However, when only a single counterion is present in solution, classical DLVO electrostatic potential energies no longer apply. Accordingly, here a new formulation is proposed to describe how single-counterion diffuse double layers interact in colloidal suspensions. Part II (Srivastav, H.; Weber, A. Z.; Radke, C. J. Langmuir 2024 DOI: 10.1021/acs.langmuir.3c03904) of this contribution uses the new single-ion interaction energies to predict aggregated size distributions and the resulting solution pH of PFSA in mixtures of n-propanol and water. A single-counterion diffuse layer cannot reach an electrically neutral concentration far from a charged particle. Consequently, nowhere in the dispersion is the solvent neutral, and the diffuse layer emanating from one particle always experiences the presence of other particles (or walls). Thus, in addition to an intervening interparticle repulsive force, a backside osmotic force is always present. With this new construction, we establish that single-ion repulsive pair interaction energies are much larger than those of classical DLVO electrostatic potentials. The proposed single-ion electrostatic pair potential governs dramatic new dispersion behavior, including dispersions that are stable at a low volume fraction but unstable at a high volume fraction and finite volume-fraction dispersions that are unstable with fine particles but stable with coarse particles. The proposed single-counterion electrostatic pair potential provides a general expression for predicting colloidal behavior for any charged particle dispersion in ionizing solvents with no added electrolyte.

10.
Langmuir ; 40(13): 6666-6674, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38498907

RESUMO

Perfluorosulfonic acid (PFSA) ionomers serve a vital role in the performance and stability of fuel-cell catalyst layers. These properties, in turn, depend on the colloidal processing of precursor inks. To understand the colloidal structure of fuel-cell catalyst layers, we explore the aggregation of PFSA ionomers dissolved in water/alcohol solutions and relate the predicted aggregation to experimental measurements of solution pH. Not all side chains contribute to measured pH because of burying inside particle aggregates. To account for the measured degree of dissociation, a new description is developed for how PFSA aggregates interact with each other. The developed single-counterion electrostatic repulsive pair potential from Part I is incorporated into the Smoluchowski collision-based kinetics of interacting aggregates with buried side chains. We demonstrate that the surrounding solvent mixture affects the degree of aggregation as well as the pH of the system primarily through the solution dielectric permittivity, which drives the strength of the interparticle repulsive energies. Successful pH prediction of Nafion ionomer dispersions in water/n-propanol solutions validates the numerical calculations. Nafion-dispersion pH measurements serve as a surrogate for Nafion particle-size distributions. The model and framework can be leveraged to explore different ink formulations.

11.
J Child Psychol Psychiatry ; 65(7): 959-972, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38124618

RESUMO

BACKGROUND: Self-regulation in early childhood develops within a social context. Variations in such development can be attributed to inter-individual behavioral differences, which can be captured both as facets of temperament and across a normal:abnormal dimensional spectrum. With increasing emphasis on irritability as a robust early-life transdiagnostic indicator of broad psychopathological risk, linkage to neural mechanisms is imperative. Currently, there is inconsistency in the identification of neural circuits that underlie irritability in children, especially in social contexts. This study aimed to address this gap by utilizing a functional magnetic resonance imaging (fMRI) paradigm to investigate pediatric anger/frustration using social stimuli. METHODS: Seventy-three children (M = 6 years, SD = 0.565) were recruited from a larger longitudinal study on irritability development. Caregivers completed questionnaires assessing irritable temperament and clinical symptoms of irritability. Children participated in a frustration task during fMRI scanning that was designed to induce frustration through loss of a desired prize to an animated character. Data were analyzed using both general linear modeling (GLM) and independent components analysis (ICA) and examined from the temperament and clinical perspectives. RESULTS: ICA results uncovered an overarching network structure above and beyond what was revealed by traditional GLM analyses. Results showed that greater temperamental irritability was associated with significantly diminished spatial extent of activation and low-frequency power in a network comprised of the posterior superior temporal sulcus (pSTS) and the precuneus (p < .05, FDR-corrected). However, greater severity along the spectrum of clinical expression of irritability was associated with significantly increased extent and intensity of spatial activation as well as low- and high-frequency neural signal power in the right caudate (p < .05, FDR-corrected). CONCLUSIONS: Our findings point to specific neural circuitry underlying pediatric irritability in the context of frustration using social stimuli. Results suggest that a deliberate focus on the construction of network-based neurodevelopmental profiles and social interaction along the normal:abnormal irritability spectrum is warranted to further identify comprehensive transdiagnostic substrates of the irritability.


Assuntos
Frustração , Humor Irritável , Imageamento por Ressonância Magnética , Rede Nervosa , Temperamento , Humanos , Humor Irritável/fisiologia , Masculino , Feminino , Criança , Temperamento/fisiologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Estudos Longitudinais , Ira/fisiologia , Comportamento Infantil/fisiologia , Pré-Escolar
12.
Proc Natl Acad Sci U S A ; 118(32)2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34344827

RESUMO

Viruses modulate mitochondrial processes during infection to increase biosynthetic precursors and energy output, fueling virus replication. In a surprising fashion, although it triggers mitochondrial fragmentation, the prevalent pathogen human cytomegalovirus (HCMV) increases mitochondrial metabolism through a yet-unknown mechanism. Here, we integrate molecular virology, metabolic assays, quantitative proteomics, and superresolution confocal microscopy to define this mechanism. We establish that the previously uncharacterized viral protein pUL13 is required for productive HCMV replication, targets the mitochondria, and functions to increase oxidative phosphorylation during infection. We demonstrate that pUL13 forms temporally tuned interactions with the mitochondrial contact site and cristae organizing system (MICOS) complex, a critical regulator of cristae architecture and electron transport chain (ETC) function. Stimulated emission depletion superresolution microscopy shows that expression of pUL13 alters cristae architecture. Indeed, using live-cell Seahorse assays, we establish that pUL13 alone is sufficient to increase cellular respiration, not requiring the presence of other viral proteins. Our findings address the outstanding question of how HCMV targets mitochondria to increase bioenergetic output and expands the knowledge of the intricate connection between mitochondrial architecture and ETC function.


Assuntos
Infecções por Citomegalovirus/metabolismo , Citomegalovirus/fisiologia , Mitocôndrias/metabolismo , Mitocôndrias/virologia , Proteínas Virais/metabolismo , Citomegalovirus/metabolismo , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/virologia , Transporte de Elétrons , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Mitocôndrias/ultraestrutura , Fosforilação Oxidativa , Proteínas Virais/genética , Replicação Viral
13.
Artigo em Inglês | MEDLINE | ID: mdl-38797162

RESUMO

INTRODUCTION: Olfactory dysfunction is a common symptom of COVID-19. However, subjective perception of olfactory function does not always correlate well with more objective measures. This study seeks to clarify associations between subjective and psychophysical measures of olfaction and gustation in patients with subjective chemosensory dysfunction following COVID-19. METHODS: Adults with persistent COVID-19-associated chemosensory disturbance were recruited for a prospective, longitudinal cohort study at a tertiary care institution. Participants provided subjective measures of olfactory and gustatory function and underwent psychophysical assessment using Sniffin' Sticks olfactory and Monell gustatory tests. RESULTS: Data analysis (n = 65) showed a statistically significant association between subjective and psychophysical measures of olfaction (p < 0.001). For each one-point increase in subjectively-reported olfactory ability, there is, on average, a 0.11 (95% CI: 0.06, 0.16; p < 0.001) point increase in TDI score while adjusting for age at baseline assessment, sex, and follow-up time. For each one-point increase in subjectively-reported olfactory ability, there is, on average, a 0.04 (95% CI: 0.02, 0.06; p < 0.001) point and 0.05 (95% CI: 0.03, 0.07; p < 0.001) point increase in discrimination and identification scores, respectively, when adjusting for age at baseline assessment, sex, and follow-up time. CONCLUSION: Subjective olfaction shows a mild to moderate association with psychophysical measures, but it fails to comprehensively assess persistent COVID-19-associated chemosensory deficits. The lack of significant association between subjective olfaction and threshold limits the utility of subjective olfaction in tracking recovery. These findings support the push for more widespread psychophysical chemosensory testing.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38330371

RESUMO

OBJECTIVES: Research suggests that acculturating to the United States is detrimental for immigrants' health. Consistent with this pattern, higher levels of U.S. acculturation among Latina-American women have been associated with giving birth to lower birth weight babies. The mechanisms that shape this shift in pregnancy health are not clear, but researchers have begun to consider the role of physiological systems that are sensitive to social experience. The present study examined the association of cultural orientation with blood pressure (BP) trajectories over the course of pregnancy. METHOD: In a study of 1,011 U.S.- and foreign-born Latina-American women, cultural orientation was assessed and multiple BP measures were collected throughout pregnancy. Postpregnancy data, including gestational age-adjusted birth weight, were extracted from medical records. Bayesian structural equation models examined average BP and slopes of BP change during pregnancy while accounting for psychosocial stress, support, and pregnancy health-related factors (e.g., maternal age, smoking). RESULTS: We found evidence that greater U.S. orientation was associated with higher diastolic blood pressure (DBP) and steeper increases in DBP, which was associated with less fetal growth. CONCLUSIONS: This is the first evidence that BP may mediate the association between cultural orientation and pregnancy outcomes in Latina-American women. These findings advance our understanding of the biopsychosocial pathways through which acculturation to the U.S. links with health. As scholars seek to better understand the influence of U.S. acculturation on health, focusing on the cardiovascular system and other physiological systems that are sensitive to social experience is warranted and likely to prove valuable. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

15.
Matern Child Health J ; 27(8): 1416-1425, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37266855

RESUMO

INTRODUCTION: Opioid-sparing protocols reduce postpartum opioid prescribing in opioid-naïve patients; however, patients with opioid use disorder (OUD) and complex pain needs who may benefit from these protocols are typically excluded from them. We assessed postpartum pain experiences of patients with OUD and chronic prenatal opioid exposure after implementation of an opioid-sparing protocol. METHODS: A phone survey assessed postpartum pain experiences for people with chronic prenatal opioid exposure who delivered between January 2020 and August 2021 at an academic hospital. Analyses included descriptive statistics, qualitative content analysis, and a joint display comparing themes. RESULTS: Of 25 patients, 18 (72%) participated; most were non-Hispanic White (100%, 18/18), publicly insured (78%, 14/18), multiparous (78%, 14/18), with OUD (100%, 18/18). No patients with a vaginal birth received an opioid prescription; half (4/8) with a cesarean birth received one at discharge. Over one-third (7/18, 39%) reported poor pain control (≥ 5/10) in the hospital and one week post-discharge; scores were higher for cesarean versus vaginal birth. Qualitative sub-analyses of open-ended responses revealed patient perceptions of postpartum pain and treatment. The most effective strategies, stratified by birth type and pain level, ranged from non-opioid medications for vaginal births and minor pain to prescription opioids for cesarean births and moderate-to-intense pain. DISCUSSION: Postpartum opioid prescribing for patients with chronic prenatal opioid use was low for vaginal and cesarean birth following implementation of an opioid-sparing protocol. Patients with OUD reported good pain management with opioid-sparing pain regimens; however, many reported poorly controlled pain immediately postpartum. Future work should assess approaches to postpartum pain management that minimize the risks of opioid medication-particularly in at-risk groups.


What is already known on this subject? Opioid-sparing protocols can reduce postpartum opioid prescribing in opioid-naïve patients; however, there are currently no clear guidelines for opioid prescribing for people with opioid use disorder (OUD) in the postpartum period.What this study adds?Postpartum opioid prescribing for patients with chronic prenatal opioid use was less than the national average and one-third of patients reported poor pain control. Opioid-sparing protocols postpartum should be expanded to patients with OUD to improve pain control and minimize risks associated with opioid medication.


Assuntos
Analgésicos Opioides , Transtornos Relacionados ao Uso de Opioides , Gravidez , Feminino , Humanos , Analgésicos Opioides/efeitos adversos , Assistência ao Convalescente , Alta do Paciente , Padrões de Prática Médica , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Dor/tratamento farmacológico , Período Pós-Parto
16.
Artigo em Inglês | MEDLINE | ID: mdl-37773333

RESUMO

BACKGROUND: Parent-infant separation resulting from admission to a neonatal intensive care unit (NICU) is often reported as the most challenging and distressing experience for parents. Aiming to mitigate the stress of parent-infant separation, a new neonatal care model was designed to integrate NIC with delivery and postpartum care. Yet, little is known about the model and its implementation. METHODS: Using a qualitative descriptive design with field observations, we describe the characteristics of an integrated-neonatal intensive care (I-NIC) model and examined perceptions of clinical staff (n = 8) and parents (n = 3). RESULTS: The physical layout of the I-NIC rooms required additional oxygen and suction columns and new signage to specify them as NICU-equipped. Other NICU-related equipment was mobile, thus moved into rooms when necessary. Nurses were cross-trained in labor/delivery, postpartum, neonatal care; however, nurses primarily worked within their specific area of expertise. Clinician and parent perceptions of the model were notably positive, reporting decreased anxiety related to separation, increased ability for chest feeding and skin-to-skin care, and improved interdisciplinary care. CONCLUSION: Future work is needed to understand implementation of the model in other settings, with specific attention to unit architecture, level of NICU care services, patient census, and staff and patient outcomes.

17.
Evol Dev ; 24(1-2): 16-36, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35239990

RESUMO

Pristionchus pacificus is a nematode model for the developmental genetics of morphological polyphenism, especially at the level of individual cells. Morphological polyphenism in this species includes an evolutionary novelty, moveable teeth, which have enabled predatory feeding in this species and others in its family (Diplogastridae). From transmission electron micrographs of serial thin sections through an adult hermaphrodite of P. pacificus, we three-dimensionally reconstructed all epithelial and myoepithelial cells and syncytia, corresponding to 74 nuclei, of its face, mouth, and pharynx. We found that the epithelia that produce the predatory morphology of P. pacificus are identical to Caenorhabditis elegans in the number of cell classes and nuclei. However, differences in cell form, spatial relationships, and nucleus position correlate with gross morphological differences from C. elegans and outgroups. Moreover, we identified fine-structural features, especially in the anteriormost pharyngeal muscles, that underlie the conspicuous, left-right asymmetry that characterizes the P. pacificus feeding apparatus. Our reconstruction provides an anatomical map for studying the genetics of polyphenism, feeding behavior, and the development of novel form in a satellite model to C. elegans.


Assuntos
Caenorhabditis elegans , Nematoides , Animais , Evolução Biológica , Caenorhabditis elegans/fisiologia , Nematoides/anatomia & histologia , Nematoides/fisiologia , Comportamento Predatório
18.
J Virol ; 95(12)2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-33762420

RESUMO

Dengue virus (DENV) is the most common vector-borne viral disease, with nearly 400 million worldwide infections each year concentrated in the tropical and subtropical regions of the world. Severe dengue complications are often associated with a secondary heterotypic infection of one of the four circulating serotypes. In this scenario, humoral immune responses targeting cross-reactive, poorly neutralizing epitopes can lead to increased infectivity of susceptible cells via antibody-dependent enhancement (ADE). In this way, antibodies produced in response to infection or vaccination are capable of contributing to enhanced disease in subsequent infections. Currently, there are no available therapeutics to combat DENV disease, and there is an urgent need for a safe and efficacious vaccine. Here, we developed a nucleotide-modified mRNA vaccine encoding the membrane and envelope structural proteins from DENV serotype 1 encapsulated in lipid nanoparticles (prM/E mRNA-LNP). Vaccination of mice elicited robust antiviral immune responses comparable to viral infection, with high levels of neutralizing antibody titers and antiviral CD4+ and CD8+ T cells. Immunocompromised AG129 mice vaccinated with the prM/E mRNA-LNP vaccine were protected from a lethal DENV challenge. Vaccination with either a wild-type vaccine or a vaccine with mutations in the immunodominant fusion loop epitope elicited equivalent humoral and cell-mediated immune responses. Neutralizing antibodies elicited by the vaccine were sufficient to protect against a lethal challenge. Both vaccine constructs demonstrated serotype-specific immunity with minimal serum cross-reactivity and reduced ADE in comparison to a live DENV1 viral infection.IMPORTANCE With 400 million worldwide infections each year, dengue is the most common vector-borne viral disease. Forty percent of the world's population is at risk, with dengue experiencing consistent geographic spread over the years. With no therapeutics available and vaccines performing suboptimally, the need for an effective dengue vaccine is urgent. Here, we develop and characterize a novel mRNA vaccine encoding the dengue serotype 1 envelope and premembrane structural proteins that is delivered via a lipid nanoparticle. Our DENV1 prM/E mRNA-LNP vaccine induces neutralizing antibody and cellular immune responses in immunocompetent mice and protects an immunocompromised mouse from a lethal DENV challenge. Existing antibodies against dengue can enhance subsequent infections via antibody-dependent enhancement (ADE). Importantly our vaccine induced only serotype-specific immune responses and did not induce ADE.


Assuntos
Vacinas contra Dengue/imunologia , Vírus da Dengue/imunologia , Dengue/prevenção & controle , Vacinas Sintéticas/imunologia , Imunidade Adaptativa , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores , Linhagem Celular , Reações Cruzadas , Dengue/imunologia , Vacinas contra Dengue/administração & dosagem , Vírus da Dengue/classificação , Vírus da Dengue/genética , Imunidade Humoral , Esquemas de Imunização , Lipossomos , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas , RNA Mensageiro/genética , RNA Viral/genética , Sorogrupo , Linfócitos T/imunologia , Vacinas Sintéticas/administração & dosagem , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia , Vacinas de mRNA
19.
Acc Chem Res ; 54(24): 4584-4594, 2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34870973

RESUMO

Redox-active ligands in coordination chemistry not only modulate the reactivity of the bound metal center but also serve as electron reservoirs to store redox equivalents. Among many applications in contemporary chemistry, the scope of redox-active ligands in biology is exemplified by the porphyrin radicals in the catalytic cycles of multiple heme enzymes (e.g., cytochrome P450, catalase) and the chlorophyll radicals in photosynthetic systems. This Account reviews the discovery of two redox-active ligands inspired by oligopyrrolic fragments found in biological settings as products of heme metabolism.Linear oligopyrroles, in which pyrrole heterocycles are linked by methylene or methine bridges, are ubiquitous in nature as part of the complex, multistep biosynthesis and degradation of hemes and chlorophylls. Bile pigments, such as biliverdin and bilirubin, are common and well-studied tetrapyrroles with characteristic pyrrolin-2-one rings at both terminal positions. The coordination chemistry of these open-chain pigments is less developed than that of porphyrins and other macrocyclic oligopyrroles; nevertheless, complexes of biliverdin and its synthetic analogs have been reported, along with fluorescent zinc complexes of phytobilins employed as bioanalytical tools. Notably, linear conjugated tetrapyrroles inherit from porphyrins the ability to stabilize unpaired electrons within their π system. The isolated complexes, however, present helical structures and generally limited stability.Smaller biopyrrins, which feature three or two pyrrole rings and the characteristic oxidized termini, have been known for several decades following their initial isolation as urinary pigments and heme metabolites. Although their coordination chemistry has remained largely unexplored, these compounds are structurally similar to the well-established tripyrrin and dipyrrin ligands employed in a broad variety of metal complexes. In this context, our study of the coordination chemistry of tripyrrin-1,14-dione and dipyrrin-1,9-dione was motivated by the potential to retain on these compact, versatile platforms the reversible ligand-based redox chemistry of larger tetrapyrrolic systems.The tripyrrindione ligand coordinates several divalent transition metals (i.e., Pd(II), Ni(II) Cu(II), Zn(II)) to form neutral complexes in which an unpaired electron is delocalized over the conjugated π system. These compounds, which are stable at room temperature and exposed to air, undergo reversible one-electron processes to access different redox states of the ligand system without affecting the oxidation state and coordination geometry of the metal center. We also characterized ligand-based radicals on the dipyrrindione platform in both homoleptic and heteroleptic complexes. In addition, this study documented noncovalent interactions (e.g., interligand hydrogen bonds with the pyrrolinone carbonyls, π-stacking of ligand-centered radicals) as important aspects of this coordination chemistry. Furthermore, the fluorescence of the zinc-bound tripyrrindione radical and the redox-switchable emission of a dipyrrindione BODIPY-type fluorophore showcased the potential interplay of redox chemistry and luminescence in these compounds. Supported by computational analyses, the portfolio of properties revealed by this investigation takes the tripyrrindione and dipyrrindione motifs of heme metabolites to the field of redox-active ligands, where they are positioned to offer new opportunities for catalysis, sensing, supramolecular systems, and functional materials.


Assuntos
Complexos de Coordenação , Heme , Ligantes , Luminescência , Oxirredução
20.
J Vasc Surg ; 76(6): 1710-1718, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35842201

RESUMO

OBJECTIVE: The financial effects of the coronavirus disease 2019 (COVID-19) pandemic have fundamentally changed the healthcare environment, with hospitals expected to have lost billions in 2021. A preexisting nationwide nursing shortage became drastically worse during the pandemic amid dramatically increasing labor costs. We examined the evolution and financial effects of these changes during repeated pandemic surges within a vascular surgery division at a tertiary medical center. METHODS: Operating room, inpatient unit, and outpatient clinic financial data were examined retrospectively. The monthly averages for a 14-month control cohort before COVID-19 (January 2019 to February 2020) were compared to the averages for seven interval groups of sequential, 3-month cohorts from March 2020 through November 2021 (groups 1-7). RESULTS: The monthly relative value unit (RVU) generation had returned to the mean before the COVID-19 pandemic (2520 RVUs) after an isolated decrease early in the pandemic (group 1; 1734 RVUs). The RVUs ranged from 2540 to 2863 per month for groups 2 to 5, with a slight decline in groups 6 and 7. The average monthly RVUs in the COVID-19 period (2437 RVUs) were nearly equivalent (P = .93) to those for the pre-COVID-19 cohort. An analysis of payor mix demonstrated an increase in commercial and Medicaid payors, with a respective decrease in Medicare payors, during COVID-19. The contribution to indirect, or profit, from inpatient hospital and outpatient clinical revenue showed a drastic decrease in group 1, followed by a swift rebound when the government restrictions were eased (group 2). The total monthly vascular nursing unit expense demonstrated a marked increase with each sequential group during COVID-19, with an average monthly upsurge of +$82,171 (+47%; P < .001). An increase in the nursing labor expenses of +$884 per vascular case (from $1630 to $2514; +54%; P < .001) was observed in the COVID-19 era. The nursing labor costs per patient day had increased from $580 to $852 (+$272; +53%; P < .001). The nursing labor cost per RVU had increased from $69.5 to $107.7 (+$38.2; +55%; P < .001). On a system-wide level, the agency-related nursing costs had increased from $4.9 million to $13.6 million per month (+178%; P < .001) in 2021 compared with 2020. CONCLUSIONS: The COVID-19 pandemic has had severe, nationwide effects on healthcare delivery, exacerbating the deleterious effects of an existing, critical nursing shortage. To the best of our knowledge, the present study is the first detailed analysis of this phenomenon and its effects on a surgical division. Our results have demonstrated a progressive, drastic increase in nursing labor costs during the pandemic, with a resultant sustained erosion of financial margins despite a level of clinical productivity, as measured in RVUs, equal to the prepandemic standards. This precarious trend is not sustainable and will require increased, targeted government funding.


Assuntos
COVID-19 , Pandemias , Idoso , Humanos , Estados Unidos/epidemiologia , COVID-19/epidemiologia , Estudos Retrospectivos , Medicare , Procedimentos Cirúrgicos Vasculares , Hospitais
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