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1.
Cureus ; 16(6): e62721, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39036200

RESUMO

Hamartoma of mature cardiac myocytes (HMCM) is a rare, benign cardiac tumor. We report a case of a 19-year-old female with an atypical presentation, including significant weight loss and abnormal electrocardiogram. A transthoracic echocardiogram (TTE) revealed a mass causing left ventricular outflow tract (LVOT) obstruction, confirmed by cardiac magnetic resonance (CMR) imaging showing a 5 x 3 cm mass contiguous with the right ventricular free wall and exhibiting heterogeneous, diffuse late gadolinium enhancement. The patient subsequently underwent sternotomy for surgical biopsy and septal myectomy, with histology of the mass being consistent with HMCM. The patient remained asymptomatic during her 6-month follow-up.

2.
CHEST Crit Care ; 2(2)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38938509

RESUMO

A 48-year-old man with history of recent travel to central Mexico and immunosuppression sought treatment with a 1-month-long history of progressive headache, fatigue, word-finding difficulties, and night sweats. The patient had a history of end-stage renal disease; he had undergone a kidney transplantation 7 years prior with good graft function with immunosuppression with tacrolimus, everolimus, and low-dose prednisone. At an outside hospital, he recently had been treated with empiric antibiotics for meningitis, but these were discontinued given the low suspicion for a bacterial cause. After discharge, he continued to have headaches, limited oral intake, persistent nausea, urinary frequency, and falls, prompting him to seek treatment at the ED. Physical examination findings were benign aside from disorientation. Laboratory workup was significant for hyponatremia of 122 mM, creatinine of 1.4 mg/dL (baseline, 1.4-1.5 mg/dL), WBC count of 7.2 109/L, hemoglobin of 13 g/dL, and platelet count of 349 109/L. Neither tacrolimus nor everolimus levels were supratherapeutic.

3.
J Intensive Care Med ; 39(3): 277-287, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37670670

RESUMO

BACKGROUND: Sepsis-associated destruction of the pulmonary microvascular endothelial glycocalyx (EGCX) creates a vulnerable endothelial surface, contributing to the development of acute respiratory distress syndrome (ARDS). Constituents of the EGCX shed into circulation, glycosaminoglycans and proteoglycans, may serve as biomarkers of endothelial dysfunction. We sought to define the patterns of plasma EGCX degradation products in children with sepsis-associated pediatric ARDS (PARDS), and test their association with clinical outcomes. METHODS: We retrospectively analyzed a prospective cohort (2018-2020) of children (≥1 month to <18 years of age) receiving invasive mechanical ventilation for acute respiratory failure for ≥72 h. Children with and without sepsis-associated PARDS were selected from the parent cohort and compared. Blood was collected at time of enrollment. Plasma glycosaminoglycan disaccharide class (heparan sulfate, chondroitin sulfate, and hyaluronan) and sulfation subtypes (heparan sulfate and chondroitin sulfate) were quantified using liquid chromatography tandem mass spectrometry. Plasma proteoglycans (syndecan-1) were measured through an immunoassay. RESULTS: Among the 39 mechanically ventilated children (29 with and 10 without sepsis-associated PARDS), sepsis-associated PARDS patients demonstrated higher levels of heparan sulfate (median 639 ng/mL [interquartile range, IQR 421-902] vs 311 [IQR 228-461]) and syndecan-1 (median 146 ng/mL [IQR 32-315] vs 8 [IQR 8-50]), both p = 0.01. Heparan sulfate subtype analysis demonstrated greater proportions of N-sulfated disaccharide levels among children with sepsis-associated PARDS (p = 0.01). Increasing N-sulfated disaccharide levels by quartile were associated with severe PARDS (n = 9/29) with the highest quartile including >60% of the severe PARDS patients (test for trend, p = 0.04). Higher total heparan sulfate and N-sulfated disaccharide levels were independently associated with fewer 28-day ventilator-free days in children with sepsis-associated PARDS (all p < 0.05). CONCLUSIONS: Children with sepsis-associated PARDS exhibited higher plasma levels of heparan sulfate disaccharides and syndecan-1, suggesting that EGCX degradation biomarkers may provide insights into endothelial dysfunction and PARDS pathobiology.


Assuntos
Síndrome do Desconforto Respiratório , Sepse , Humanos , Criança , Estudos Retrospectivos , Sindecana-1/metabolismo , Sulfatos de Condroitina/metabolismo , Estudos Prospectivos , Glicocálix/química , Glicocálix/metabolismo , Sepse/complicações , Sepse/metabolismo , Heparitina Sulfato/metabolismo , Biomarcadores , Proteoglicanas/metabolismo , Dissacarídeos/metabolismo
4.
Mol Cancer Ther ; 23(1): 14-23, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37756579

RESUMO

Geranylgeranyl diphosphate synthase (GGDPS), the source of the isoprenoid donor in protein geranylgeranylation reactions, has become an attractive target for anticancer therapy due to the reliance of cancers on geranylgeranylated proteins. Current GGDPS inhibitor development focuses on optimizing the drug-target enzyme interactions of nitrogen-containing bisphosphonate-based drugs. To advance GGDPS inhibitor development, understanding the enzyme structure, active site, and ligand/product interactions is essential. Here we provide a comprehensive structure-focused review of GGDPS. We reviewed available yeast and human GGDPS structures and then used AlphaFold modeling to complete unsolved structural aspects of these models. We delineate the elements of higher-order structure formation, product-substrate binding, the electrostatic surface, and small-molecule inhibitor binding. With the rise of structure-based drug design, the information provided here will serve as a valuable tool for rationally optimizing inhibitor selectivity and effectiveness.


Assuntos
Inibidores Enzimáticos , Neoplasias , Humanos , Farnesiltranstransferase/química , Farnesiltranstransferase/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Inibidores Enzimáticos/química , Terpenos/química , Terpenos/farmacologia , Prenilação de Proteína , Neoplasias/tratamento farmacológico
5.
J Virol ; 97(10): e0124123, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37772824

RESUMO

IMPORTANCE: CD34+ hematopoietic progenitor cells (HPCs) are an important cellular reservoir for latent human cytomegalovirus (HCMV). Several HCMV genes are expressed during latency that are involved with the maintenance of the viral genome in CD34+ HPC. However, little is known about the process of viral reactivation in these cells. Here, we describe a viral protein, pUL8, and its interaction and stabilization with members of the Wnt/ß-catenin pathway as an important component of viral reactivation. We further define that pUL8 and ß-catenin interact with DVL2 via a PDZ-binding domain, and loss of UL8 interaction with ß-catenin-DVL2 restricts viral reactivation. Our findings will be instrumental in understanding the molecular processes involved in HCMV reactivation in order to design new antiviral therapeutics.


Assuntos
Antígenos CD34 , Citomegalovirus , Proteínas Desgrenhadas , Células-Tronco Hematopoéticas , Proteínas Virais , Ativação Viral , beta Catenina , Humanos , Antígenos CD34/metabolismo , beta Catenina/química , beta Catenina/metabolismo , Citomegalovirus/genética , Citomegalovirus/fisiologia , Proteínas Desgrenhadas/química , Proteínas Desgrenhadas/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/virologia , Domínios PDZ , Proteínas Virais/química , Proteínas Virais/metabolismo , Latência Viral/genética
6.
Int J STD AIDS ; 34(14): 1053-1061, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37608625

RESUMO

BACKGROUND: Protease inhibitors (PIs) have contributed to the long-term survival of persons with human immunodeficiency virus (PHIV). While there is a concern linking protease inhibitors to an increased risk of heart failure (HF), the evidence linking protease inhibitors and heart failure has been uncertain. METHODS: Following the PRISMA Extension for Scoping Reviews, we searched MEDLINE and EMBASE for peer-reviewed articles using keywords including "protease inhibitor," "heart failure," and "human immunodeficiency virus" from their inception to December 21, 2022. RESULTS: Five articles, including three observational studies and two randomized controlled trials, were included in the review. While protease inhibitors seem to be associated with atherosclerotic cardiovascular disease through their effects on metabolic markers, there is scarce evidence suggesting a direct association between protease inhibitors and heart failure. Although one study showed a possible correlation between protease inhibitor use and lower left ventricular ejection fraction and increased heart failure admission, the results were subject to confounders, and participants had poor medication adherence. CONCLUSION: Although current data are conflicting, there could be an association between PIs and HF in PHIV. Future prospective studies are warranted to evaluate the incidence of heart failure stratified on the generation of PIs and with adjustment for other metabolic risk factors.


Assuntos
Anti-Infecciosos , Insuficiência Cardíaca , Humanos , Inibidores de Proteases/efeitos adversos , Volume Sistólico , Função Ventricular Esquerda , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/tratamento farmacológico , Fatores de Risco , Antivirais/uso terapêutico , HIV , Anti-Infecciosos/uso terapêutico
7.
Cardiovasc Pathol ; 65: 107538, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37031829

RESUMO

BACKGROUND: While primary cardiac tumors are rare, it has been increasingly recognized due to improvement in screening measures. However, the hamartoma of mature cardiac myocytes has been underrecognized compared to other cardiac tumors, such as cardiac myxomas and papillary fibroelastomas, and is still potentially associated with critical consequences such as sudden death. This systematic review aims to summarize the evidence regarding the hamartoma of mature cardiac myocytes and characterize the presentations and symptoms for clinicians. METHODS: Following the PRISMA statement, we searched MEDLINE and EMBASE for all peer-reviewed articles using keywords including "hamartoma of mature cardiac myocytes" from their inception to January 2, 2023. RESULTS: We included 25 articles, including 34 cases, in this systematic review. Patients with hamartoma of mature cardiac myocytes commonly presented with nonspecific symptoms such as dyspnea (35.3%), although a few presented with sudden death and syncope. The left ventricle was the common site of origin (41.2%), followed by the right atrium and ventricle. Surgery was commonly pursued for diagnosis and treatment, while a few required cardiac transplants (8.8%), and 29.4% were diagnosed with autopsy or expired. CONCLUSION: Hamartoma of mature cardiac myocytes is a potentially underrecognized primary cardiac tumor associated with treatable yet potentially critical consequences. Given the challenges of differentiating it from malignancy such as angiosarcoma, multimodal imaging needs to be utilized to pursue a diagnosis. Future studies are warranted to develop a noninvasive diagnosis mode for cardiac tumor.


Assuntos
Hamartoma , Neoplasias Cardíacas , Humanos , Miócitos Cardíacos/patologia , Neoplasias Cardíacas/patologia , Ventrículos do Coração/patologia , Hamartoma/diagnóstico , Hamartoma/patologia , Hamartoma/cirurgia , Morte Súbita/patologia
8.
Semin Cell Dev Biol ; 139: 84-92, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35370089

RESUMO

A significant proportion of brains with Alzheimer's disease pathology are obtained from patients that were cognitively normal, suggesting that differences within the brains of these individuals made them resilient to the disease. Here, we describe recent approaches that specifically increase synaptic resilience, as loss of synapses is considered to be the first change in the brains of Alzheimer's patients. We start by discussing studies showing benefit from increased expression of neurotrophic factors and protective genes. Methods that effectively make dendritic spines stronger, specifically by acting through actin network proteins, scaffolding proteins and inhibition of phosphatases are described next. Importantly, the therapeutic strategies presented in this review tackle Alzheimer's disease not by targeting plaques and tangles, but instead by making synapses resilient to the pathology associated with Alzheimer's disease, which has tremendous potential.


Assuntos
Doença de Alzheimer , Humanos , Animais , Camundongos , Doença de Alzheimer/genética , Encéfalo/metabolismo , Sinapses/metabolismo , Actinas/metabolismo , Modelos Animais de Doenças , Camundongos Transgênicos
9.
BMC Pediatr ; 22(1): 542, 2022 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-36100848

RESUMO

BACKGROUND: Bronchopulmonary dysplasia (BPD) is one of the most common and serious sequelae of prematurity. Prompt diagnosis using prediction tools is crucial for early intervention and prevention of further adverse effects. This study aims to develop a BPD-free survival prediction tool based on the concept of the developmental origin of BPD with machine learning. METHODS: Datasets comprising perinatal factors and early postnatal respiratory support were used for initial model development, followed by combining the two models into a final ensemble model using logistic regression. Simulation of clinical scenarios was performed. RESULTS: Data from 689 infants were included in the study. We randomly selected data from 80% of infants for model development and used the remaining 20% for validation. The performance of the final model was assessed by receiver operating characteristics which showed 0.921 (95% CI: 0.899-0.943) and 0.899 (95% CI: 0.848-0.949) for the training and the validation datasets, respectively. Simulation data suggests that extubating to CPAP is superior to NIPPV in BPD-free survival. Additionally, successful extubation may be defined as no reintubation for 9 days following initial extubation. CONCLUSIONS: Machine learning-based BPD prediction based on perinatal features and respiratory data may have clinical applicability to promote early targeted intervention in high-risk infants.


Assuntos
Displasia Broncopulmonar , Doenças do Prematuro , Displasia Broncopulmonar/diagnóstico , Displasia Broncopulmonar/prevenção & controle , Feminino , Retardo do Crescimento Fetal , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Aprendizado de Máquina
10.
J Antimicrob Chemother ; 77(11): 2908-2921, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-35971666

RESUMO

BACKGROUND: Cefepime-induced neurotoxicity (CIN) has been well acknowledged among clinicians, although there are no clear diagnostic criteria or specific laboratory testing to help with its diagnosis. We aimed to summarize the existing evidence regarding CIN and provide future agendas for research. METHODS: Following the PRISMA Extension for Scoping Reviews, we searched MEDLINE and Embase for all peer-reviewed articles using keywords including 'cefepime', 'neurotoxicity', 'encephalopathy' and 'seizure', from their inception to 20 January 2022. RESULTS: We included 92 articles, including 23 observational studies and 69 cases from case reports and case series, in the systematic review. Among 119 patients with CIN, 23.5% were in the ICU at the time of diagnosis and nearly 90% of the cases showed renal dysfunction.Cefepime overdoses were described in 41%. The median latency period of developing CIN from cefepime initiation was 4 days, and about 12% developed CIN during empirical treatment. CIN patients commonly manifested altered mental status (93%), myoclonus (37%) and non-convulsive seizure epilepticus (28%). A serum cefepime trough level of >20 mg/L would put patients at risk for CIN. CIN-related symptoms were ameliorated in 97.5% by dose reduction or discontinuation of cefepime, with median time to improvement of 3 days. No CIN-associated deaths were reported. CONCLUSIONS: This systematic review summarizes the current evidence and characteristics of CIN. In the current situation where there are no CIN diagnostic criteria and the drug monitoring platform is not routinely available, candidates for cefepime should be carefully selected. Also, based on these findings, it needs to be appropriately dosed to avoid the development of CIN.


Assuntos
Encefalopatias , Síndromes Neurotóxicas , Humanos , Cefepima/efeitos adversos , Cefalosporinas/efeitos adversos , Antibacterianos/efeitos adversos , Síndromes Neurotóxicas/etiologia , Encefalopatias/induzido quimicamente
11.
Water Res ; 207: 117758, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34731671

RESUMO

The objective of this study was to quantify potential mitigation of environmental impacts from the operation and construction of wastewater treatment plants (WWTP) from implementing specific design recommendations. The study investigated small WWTPs, many of which are serving slow growing or declining populations. Life Cycle Assessment methodology was used to evaluate and compare the inventory and environmental impacts of nine small WWTP case studies. Detailed inventory data was collected from the facilities' engineering design plans and utility bills. One recommended practice was to avoid significant overdesign by planning for no lower than a 75% capacity utilization by the facilities' end-of-life. A theoretical correction to a 75% capacity utilization was estimated to mitigate 0.4% of lifetime electricity usage and 1% of secondary process concrete for every 1% reduction in design average flow rate. Relatedly, a 0.4% mitigation in the Carcinogenic and Global Warming impacts could be achieved for every 1% reduction in design average flow toward a 75% capacity utilization. Other suggested practices were focused on conveyance, namely, to minimize non-process facility area and to use polyvinyl chloride pipe instead of ductile iron pipe where possible. The latter practice was estimated to mitigate between 1.1 and 4.8% of the Carcinogenic impact in the nine case studies.


Assuntos
Eliminação de Resíduos Líquidos , Purificação da Água , Animais , Meio Ambiente , Estágios do Ciclo de Vida , Águas Residuárias
12.
PLoS Pathog ; 17(8): e1009380, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34411201

RESUMO

Human cytomegalovirus (HCMV) microRNAs (miRNAs) significantly rewire host signaling pathways to support the viral lifecycle and regulate host cell responses. Here we show that SMAD3 expression is regulated by HCMV miR-UL22A and contributes to the IRF7-mediated induction of type I IFNs and IFN-stimulated genes (ISGs) in human fibroblasts. Addition of exogenous TGFß interferes with the replication of a miR-UL22A mutant virus in a SMAD3-dependent manner in wild type fibroblasts, but not in cells lacking IRF7, indicating that downregulation of SMAD3 expression to limit IFN induction is important for efficient lytic replication. These findings uncover a novel interplay between SMAD3 and innate immunity during HCMV infection and highlight the role of viral miRNAs in modulating these responses.


Assuntos
Infecções por Citomegalovirus/microbiologia , Citomegalovirus/fisiologia , Fibroblastos/microbiologia , Imunidade Inata/imunologia , Interferon Tipo I/metabolismo , MicroRNAs/genética , Fator de Crescimento Transformador beta/metabolismo , Fibroblastos/imunologia , Fibroblastos/patologia , Interações Hospedeiro-Patógeno , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Interferon Tipo I/genética , Proteína Smad3/genética , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/genética , Fenômenos Fisiológicos Virais
13.
Front Neurol ; 12: 618021, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194378

RESUMO

Background: Myasthenia gravis (MG) is an autoimmune disorder of unknown etiology in most patients, in which autoantibodies target components of neuromuscular junctions and impair nerve to muscle transmission. Objective: To provide a synthesis of the evidence examining infectious agents associated with the onset of MG. Hypothesis: We hypothesized that microbes play a pathogenic role in the initiation of MG. For clinical cases, the onset of clinical signs is used as a proxy for the true onset of autoimmunity. Methods: We searched PubMed and Web of Science. Papers captured through database searching (n = 827) were assessed, yielding a total of 42 publications meeting the inclusion and exclusion criteria. An additional 6 papers were retrieved from the reference lists of relevant articles. For each pathogen, an integrated metric of evidence (IME) value, from minus 8 to plus 8, was computed based on study design, quality of data, confidence of infectious disease diagnosis, likelihood of a causal link between the pathogen and MG, confidence of MG diagnosis, and the number of infected patients. Negative IME values corresponded to studies providing evidence against a role for microbes as triggers of MG. Results: One hundred and sixty-nine myasthenic patients infected with 21 different pathogens were documented. Epstein-Barr virus (median = 4.71), human papillomavirus (median = 4.35), and poliovirus (median = 4.29) demonstrated the highest IME values. The total median IME was 2.63 (mean = 2.53; range -3.79-5.25), suggesting a general lack of evidence for a causal link. Conclusions: There was a notable absence of mechanistic studies designed to answer this question directly. The question of the pathogenic contribution of microbes to MG remains open.

14.
Front Pharmacol ; 12: 668337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113253

RESUMO

The amygdala is an important neural substrate for the emotional-affective dimension of pain and modulation of pain. The central nucleus (CeA) serves major amygdala output functions and receives nociceptive and affected-related information from the spino-parabrachial and lateral-basolateral amygdala (LA-BLA) networks. The CeA is a major site of extra-hypothalamic expression of corticotropin releasing factor (CRF, also known as corticotropin releasing hormone, CRH), and amygdala CRF neurons form widespread projections to target regions involved in behavioral and descending pain modulation. Here we explored the effects of modulating amygdala neurons on nociceptive processing in the spinal cord and on pain-like behaviors, using optogenetic activation or silencing of BLA to CeA projections and CeA-CRF neurons under normal conditions and in an acute pain model. Extracellular single unit recordings were made from spinal dorsal horn wide dynamic range (WDR) neurons, which respond more strongly to noxious than innocuous mechanical stimuli, in normal and arthritic adult rats (5-6 h postinduction of a kaolin/carrageenan-monoarthritis in the left knee). For optogenetic activation or silencing of CRF neurons, a Cre-inducible viral vector (DIO-AAV) encoding channelrhodopsin 2 (ChR2) or enhanced Natronomonas pharaonis halorhodopsin (eNpHR3.0) was injected stereotaxically into the right CeA of transgenic Crh-Cre rats. For optogenetic activation or silencing of BLA axon terminals in the CeA, a viral vector (AAV) encoding ChR2 or eNpHR3.0 under the control of the CaMKII promoter was injected stereotaxically into the right BLA of Sprague-Dawley rats. For wireless optical stimulation of ChR2 or eNpHR3.0 expressing CeA-CRF neurons or BLA-CeA axon terminals, an LED optic fiber was stereotaxically implanted into the right CeA. Optical activation of CeA-CRF neurons or of BLA axon terminals in the CeA increased the evoked responses of spinal WDR neurons and induced pain-like behaviors (hypersensitivity and vocalizations) under normal condition. Conversely, optical silencing of CeA-CRF neurons or of BLA axon terminals in the CeA decreased the evoked responses of spinal WDR neurons and vocalizations, but not hypersensitivity, in the arthritis pain model. These findings suggest that the amygdala can drive the activity of spinal cord neurons and pain-like behaviors under normal conditions and in a pain model.

16.
Cell Host Microbe ; 27(1): 104-114.e4, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31866424

RESUMO

Infection with human cytomegalovirus (HCMV) remains a significant cause of morbidity and mortality following hematopoietic stem cell transplant (HSCT) because of various hematologic problems, including myelosuppression. Here, we demonstrate that latently expressed HCMV miR-US5-2 downregulates the transcriptional repressor NGFI-A binding protein (NAB1) to induce myelosuppression of uninfected CD34+ hematopoietic progenitor cells (HPCs) through an increase in TGF-ß production. Infection of HPCs with an HCMVΔmiR-US5-2 mutant resulted in decreased TGF-ß expression and restoration of myelopoiesis. In contrast, we show that infected HPCs are refractory to TGF-ß signaling as another HCMV miRNA, miR-UL22A, downregulates SMAD3, which is required for maintenance of latency. Our data suggest that latently expressed viral miRNAs manipulate stem cell homeostasis by inducing secretion of TGF-ß while protecting infected HPCs from TGF-ß-mediated effects on viral latency and reactivation. These observations provide a mechanism through which HCMV induces global myelosuppression following HSCT while maintaining lifelong infection in myeloid lineage cells.


Assuntos
Citomegalovirus , Células-Tronco Hematopoéticas/virologia , MicroRNAs/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Latência Viral , Antígenos CD34/metabolismo , Células Cultivadas , Citomegalovirus/genética , Citomegalovirus/metabolismo , Infecções por Citomegalovirus/metabolismo , Regulação para Baixo , Células HEK293 , Células-Tronco Hematopoéticas/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Células Mieloides/metabolismo , Células Mieloides/virologia , Proteínas Repressoras/metabolismo , Transdução de Sinais , Proteína Smad3/metabolismo , Ativação Viral , Latência Viral/genética , Latência Viral/fisiologia
17.
J Cell Biol ; 219(1)2020 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-31740506

RESUMO

Multi-ciliary arrays promote fluid flow and cellular motility using the polarized and coordinated beating of hundreds of motile cilia. Tetrahymena basal bodies (BBs) nucleate and position cilia, whereby BB-associated striated fibers (SFs) promote BB anchorage and orientation into ciliary rows. Mutants that shorten SFs cause disoriented BBs. In contrast to the cytotaxis model, we show that disoriented BBs with short SFs can regain normal orientation if SF length is restored. In addition, SFs adopt unique lengths by their shrinkage and growth to establish and maintain BB connections and cortical interactions in a ciliary force-dependent mechanism. Tetrahymena SFs comprise at least eight uniquely localizing proteins belonging to the SF-assemblin family. Loss of different proteins that localize to the SF base disrupts either SF steady-state length or ciliary force-induced SF elongation. Thus, the dynamic regulation of SFs promotes BB connections and cortical interactions to organize ciliary arrays.


Assuntos
Corpos Basais/fisiologia , Cílios/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Proteínas de Protozoários/metabolismo , Tetrahymena thermophila/crescimento & desenvolvimento , Tetrahymena thermophila/metabolismo , Fenômenos Mecânicos , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Protozoários/genética , Tetrahymena thermophila/genética
18.
Cell Rep ; 29(7): 1893-1908.e4, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31722205

RESUMO

People with Down syndrome (DS; trisomy 21) display a different disease spectrum relative to the general population, including lower rates of solid malignancies and higher incidence of neurological and autoimmune conditions. However, the mechanisms driving this unique clinical profile await elucidation. We completed a deep mapping of the immune system in adults with DS using mass cytometry to evaluate 100 immune cell types, which revealed global immune dysregulation consistent with chronic inflammation, including key changes in the myeloid and lymphoid cell compartments. Furthermore, measurement of interferon-inducible phosphorylation events revealed widespread hypersensitivity to interferon-α in DS, with cell-type-specific variations in downstream intracellular signaling. Mechanistically, this could be explained by overexpression of the interferon receptors encoded on chromosome 21, as demonstrated by increased IFNAR1 surface expression in all immune lineages tested. These results point to interferon-driven immune dysregulation as a likely contributor to the developmental and clinical hallmarks of DS.


Assuntos
Síndrome de Down/imunologia , Interferon-alfa/imunologia , Adulto , Síndrome de Down/patologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade
19.
mBio ; 10(4)2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31431555

RESUMO

Human cytomegalovirus (HCMV) infection of CD34+ hematopoietic progenitor cells (CD34+ HPCs) provides a critical reservoir of virus in stem cell transplant patients, and viral reactivation remains a significant cause of morbidity and mortality. The HCMV chemokine receptor US28 is implicated in the regulation of viral latency and reactivation. To explore the role of US28 signaling in latency and reactivation, we analyzed protein tyrosine kinase signaling in CD34+ HPCs expressing US28. US28-ligand signaling in CD34+ HPCs induced changes in key regulators of cellular activation and differentiation. In vitro latency and reactivation assays utilizing CD34+ HPCs indicated that US28 was required for viral reactivation but not latency establishment or maintenance. Similarly, humanized NSG mice (huNSG) infected with TB40E-GFP-US28stop failed to reactivate upon treatment with granulocyte-colony-stimulating factor, but viral genome levels were maintained. Interestingly, HCMV-mediated changes in hematopoiesis during latency in vivo and in vitro was also dependent upon US28, as US28 directly promoted differentiation toward the myeloid lineage. To determine whether US28 constitutive activity and/or ligand-binding activity were required for latency and reactivation, we infected both huNSG mice and CD34+ HPCs in vitro with HCMV TB40E-GFP containing the US28-R129A mutation (no CA) or Y16F mutation (no ligand binding). TB40E-GFP-US28-R129A was maintained during latency and exhibited normal reactivation kinetics. In contrast, TB40E-GFP-US28-Y16F exhibited high levels of viral genome during latency and reactivation, indicating that the virus did not establish latency. These data indicate that US28 is necessary for viral reactivation and ligand binding activity is required for viral latency, highlighting the complex role of US28 during HCMV latency and reactivation.IMPORTANCE Human cytomegalovirus (HCMV) can establish latency following infection of CD34+ hematopoietic progenitor cells (HPCs), and reactivation from latency is a significant cause of viral disease and accelerated graft failure in bone marrow and solid-organ transplant patients. The precise molecular mechanisms of HCMV infection in HPCs are not well defined; however, select viral gene products are known to regulate aspects of latency and reactivation. The HCMV-encoded chemokine receptor US28, which binds multiple CC chemokines as well as CX3CR1, is expressed both during latent and lytic phases of the virus life cycle and plays a role in latency and reactivation. However, the specific timing of US28 expression and the role of ligand binding in these processes are not well defined. In this report, we determined that US28 is required for reactivation but not for maintaining latency. However, when present during latency, US28 ligand binding activity is critical to maintaining the virus in a quiescent state. We attribute the regulation of both latency and reactivation to the role of US28 in promoting myeloid lineage cell differentiation. These data highlight the dynamic and multifunctional nature of US28 during HCMV latency and reactivation.


Assuntos
Antígenos CD34/metabolismo , Citomegalovirus/fisiologia , Células-Tronco Hematopoéticas/virologia , Ligantes , Receptores de Quimiocinas/metabolismo , Proteínas Virais/metabolismo , Latência Viral/fisiologia , Animais , Diferenciação Celular , Citomegalovirus/genética , Citomegalovirus/patogenicidade , Genoma Viral , Hematopoese , Interações Hospedeiro-Patógeno , Humanos , Camundongos , Receptores de Quimiocinas/genética , Transdução de Sinais , Proteínas Virais/genética , Ativação Viral/genética , Ativação Viral/fisiologia
20.
Curr Hematol Malig Rep ; 14(2): 63-69, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30788667

RESUMO

PURPOSE OF REVIEW: Solitary plasmacytoma is a rare plasma cell dyscrasia, classified as solitary bone plasmacytoma or solitary extramedullary plasmacytoma. These entities are diagnosed by demonstrating infiltration of a monoclonal plasma cell population in a single bone lesion or presence of plasma cells involving a soft tissue mass, respectively. Both diseases represent a single localized process without significant plasma cell infiltration into the bone marrow or evidence of end organ damage. Clinically, it is important to classify plasmacytoma as having completely undetectable bone marrow involvement versus minimal marrow involvement. Here, we discuss the diagnosis, management, and prognosis of solitary plasmacytoma. RECENT FINDINGS: There have been numerous therapeutic advances in the treatment of multiple myeloma over the last few years. While the treatment paradigm for solitary plasmacytoma has not changed significantly over the years, progress has been made with regard to diagnostic tools available that can risk stratify disease, offer prognostic value, and discern solitary plasmacytoma from quiescent or asymptomatic myeloma at the time of diagnosis. Despite various studies investigating the use of systemic therapy or combined modality therapy for the treatment of plasmacytoma, radiation therapy remains the mainstay of therapy. Much of the recent advancement in the management of solitary plasmacytoma has been through the development of improved diagnostic techniques.


Assuntos
Neoplasias Ósseas/terapia , Mieloma Múltiplo/terapia , Proteínas do Mieloma/análise , Plasmócitos/patologia , Plasmocitoma/terapia , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/diagnóstico por imagem , Quimiorradioterapia/métodos , Fluordesoxiglucose F18 , Humanos , Imageamento por Ressonância Magnética/métodos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/diagnóstico por imagem , Plasmocitoma/diagnóstico , Plasmocitoma/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos
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