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Oncogenic mutations within the epidermal growth factor receptor (EGFR) are found in 15 to 30% of all non-small-cell lung carcinomas. The term exon 19 deletion (ex19del) is collectively used to refer to more than 20 distinct genomic alterations within exon 19 that comprise the most common EGFR mutation subtype in lung cancer. Despite this heterogeneity, clinical treatment decisions are made irrespective of which EGFR ex19del variant is present within the tumor, and there is a paucity of information regarding how individual ex19del variants influence protein structure and function. Herein, we identified allele-specific functional differences among ex19del variants attributable to recurring sequence and structure motifs. We built all-atom structural models of 60 ex19del variants identified in patients and combined molecular dynamics simulations with biochemical and biophysical experiments to analyze three ex19del mutations (E746_A750, E746_S752 > V, and L747_A750 > P). We demonstrate that sequence variation in ex19del alters oncogenic cell growth, dimerization propensity, enzyme kinetics, and tyrosine kinase inhibitor (TKI) sensitivity. We show that in contrast to E746_A750 and E746_S752 > V, the L747_A750 > P variant forms highly active ligand-independent dimers. Enzyme kinetic analysis and TKI inhibition experiments suggest that E746_S752 > V and L747_A750 > P display reduced TKI sensitivity due to decreased adenosine 5'-triphosphate Km. Through these analyses, we propose an expanded framework for interpreting ex19del variants and considerations for therapeutic intervention.
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Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Éxons , Neoplasias Pulmonares , Alelos , Motivos de Aminoácidos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Ativação Enzimática/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/química , Receptores ErbB/genética , Éxons/genética , Humanos , Cinética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Recidiva Local de Neoplasia/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Deleção de SequênciaRESUMO
BACKGROUND: The intermediate filament protein vimentin is widely recognized as a molecular marker of epithelial-to-mesenchymal transition. Although vimentin expression is strongly associated with cancer metastatic potential, the exact role of vimentin in cancer metastasis and the underlying mechanism of its pro-metastatic functions remain unclear. RESULTS: This study revealed that vimentin can enhance integrin ß1 surface expression and induce integrin-dependent clustering of cells, shielding them against anoikis cell death. The increased integrin ß1 surface expression in suspended cells was caused by vimentin-mediated protection of the internal integrin ß1 pool against lysosomal degradation. Additionally, cell detachment was found to induce vimentin Ser38 phosphorylation, allowing the translocation of internal integrin ß1 to the plasma membrane. Furthermore, the use of an inhibitor of p21-activated kinase PAK1, one of the kinases responsible for vimentin Ser38 phosphorylation, significantly reduced cancer metastasis in animal models. CONCLUSIONS: These findings suggest that vimentin can act as an integrin buffer, storing internalized integrin ß1 and releasing it when needed. Overall, this study provides insights regarding the strong correlation between vimentin expression and cancer metastasis and a basis for blocking metastasis using this novel therapeutic mechanism.
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Anoikis , Integrina beta1 , Vimentina , Vimentina/metabolismo , Vimentina/genética , Integrina beta1/metabolismo , Integrina beta1/genética , Humanos , Animais , Sobrevivência Celular , Camundongos , Linhagem Celular Tumoral , Fosforilação , Quinases Ativadas por p21/metabolismo , Quinases Ativadas por p21/genéticaRESUMO
Circularly polarized light emission is a crucial application in imaging, sensing, and photonics. However, utilizing low-energy photons to excite materials, as opposed to high-energy light excitation, can facilitate deep-tissue imaging and sensing applications. The challenge lies in finding materials capable of directly generating circularly polarized nonlinear optical effects. In this study, we introduce a chiral hybrid lead halide (CHLH) material system, R/S-DPEDPb3Br8·H2O (DPED = 1,2-diphenylethylenediammonium), which can directly produce circularly polarized second harmonic generation (CP-SHG) through linearly polarized infrared light excitation, exhibiting a polarization efficiency as high as 37% at room temperature. To understand the spin relaxation mechanisms behind the high polarization efficiency, we utilized two models, so-called D'yakonov-Perel' (DP) and Bir-Aronov-Pikus (BAP) mechanisms. The unique zigzag inorganic frameworks within the hybrid structure are believed to reduce the dielectric confinement and exciton binding energy, thus enhancing spin polarization, especially in regions with a high excitation pump fluence based on the DP mechanism. In the case of low excitation pump fluence, the BAP mechanism dominates, as evidenced by the observed decrease in the polarization ratio from CP-SHG measurement. Using density functional theory analysis, we elucidate how the distinctive 8-coordination environment of lead bromide building blocks effectively suppresses spin-orbit coupling at the conduction band minimum. This suppression significantly diminishes spin-splitting, thereby slowing the spin relaxation rate.
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Long noncoding RNA (lncRNA) differentiation antagonizing noncoding RNA (DANCR) is overexpressed in human triple-negative breast cancer (TNBC) and promotes cell migration and proliferation. TNBC is limited in treatment options relative to hormone-receptor-positive breast cancer and is commonly treated with chemotherapy, which is often compromised by acquired resistance. DANCR has been implicated in the development of chemoresistance across multiple cancer types. Here, we applied magnetic resonance molecular imaging (MRMI) with a targeted contrast agent, MT218, specific to extradomain-B fibronectin (EDB-FN), a marker for epithelial-to-mesenchymal transition, to assess the therapeutic efficacy of the combination of paclitaxel and ZD2-PEG-ECO/siDANCR nanoparticles (ZD2-siDANCR-ELNP) to treat TNBC. The treatment of orthotopic MDA-MB-231 TNBC in mice with paclitaxel significantly suppressed tumor growth but with a significant increase of EDB-FN in the tumor, as revealed by MRMI and immunohistochemistry. Combining ZD2-siDANCR-ELNP with paclitaxel further reduced tumor sizes, along with reduced EDB-FN expression. Interestingly, MT218-MRMI revealed a lower reduction of tumor signal enhancement with the combination treatment than that with the siDANCR treatment alone, which was supported by higher cell density in the tumors treated with the combination therapy, as shown by histochemical analysis. MT218-MRMI clearly revealed the changes of the tumor microenvironment in response to various therapies and is effective to noninvasively assess the response of TNBC tumors to the therapies. Regulating oncogenic lncRNA DANCR is an effective strategy for improving the outcomes of chemotherapy in TNBC.
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RNA Longo não Codificante , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , RNA Longo não Codificante/genética , Interferência de RNA , Linhagem Celular Tumoral , Paclitaxel/uso terapêutico , Espectroscopia de Ressonância Magnética , Imagem Molecular/métodos , Proliferação de Células , Microambiente TumoralRESUMO
Due to the lack of treatment guidelines for the management of advanced-stage marginal zone lymphoma (MZL), only one chemoimmunotherapy-cyclophosphamide, vincristine, and prednisone plus rituximab (R-CVP)-is reimbursed in the first-line setting in South Korea. The aim of this study was to develop a consensus-based recommendation for the treatment of patients with advanced-stage MZL. Twelve hematologist oncologists participated in a two-round Delphi process to identify consensus on the management of patients with advanced-stage MZL in South Korea. Physicians rated their level of agreement with each statement on a four-point Likert scale. Statements were divided into two sections: definitions used in clinical practice and clinical management of patients with advanced-stage MZL. Consensus was reached for 23 of 33 (69.7%) and 5 of 13 statements (38.5%) in rounds 1 and 2, respectively. There was strong consensus (91.7%) that advanced-stage MZL subtypes are defined according to the Lugano staging system. First-line systemic treatment should be prescribed for patients with symptomatic advanced-stage MZL. Although there was unanimous agreement that R-CVP is the standard first-line treatment for advanced-stage MZL, physicians also agreed that bendamustine with rituximab (BR) has greater efficacy than R-CVP as first-line treatment (91.7%). For the treatment of relapsed/refractory advanced-stage MZL, BR and R-CVP can be repeated in patients with short (< 24 months) and long remission periods (≥ 24 months), respectively. This study provides insights on the management of patients with advanced-stage MZL in South Korea. This may enhance clinical decision-making, thus improving patient outcomes.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Ciclofosfamida , Técnica Delphi , Linfoma de Zona Marginal Tipo Células B , Humanos , República da Coreia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Zona Marginal Tipo Células B/terapia , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Linfoma de Zona Marginal Tipo Células B/patologia , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Estadiamento de Neoplasias , Rituximab/administração & dosagem , Consenso , Vincristina/administração & dosagem , Vincristina/uso terapêutico , Prednisona/administração & dosagem , Prednisona/uso terapêutico , Masculino , Feminino , Guias de Prática Clínica como AssuntoRESUMO
We examine the effects of New York's paid family leave (PFL) policy, introduced in January 2018, on food security. While researchers evaluating PFL policies in the past have mostly focused on employment and health outcomes, we believe that an improved understanding of potential impacts on food security is pivotal as it is directly related to the health and well-being of mothers and new-borns during the postnatal months. Our analysis uses two primary data sets-Current Population Survey Food Security Supplement (CPS-FSS) and Panel Study of Income Dynamics. Estimating difference-in-differences and triple difference models, we show that New York's PFL reduced the prevalence of low food security by 36% in both datasets. The positive effects are more sizable for households with low-educated heads and families with incomes under 185% of the Federal Poverty Line. These findings highlight that paid leave benefits lead to a larger reduction in food insecurity among disadvantaged families and thus have the potential to reduce existing societal inequalities. When examining potential mechanisms through which New York's PFL law improves food security, we show that the policy increased food expenditures, increased labor force participation, particularly by mothers, and improved parental health.
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Licença para Cuidar de Pessoa da Família , Humanos , New York , Feminino , Adulto , Fome , Pobreza , Fatores Socioeconômicos , Masculino , Segurança Alimentar , Insegurança Alimentar , Renda , Mães/estatística & dados numéricos , Emprego/estatística & dados numéricos , Características da FamíliaRESUMO
Ceramide is a lipid moiety synthesized via the enzymatic activity of ceramide synthases (CerSs), six of which have been identified in mammalian cells, and each of which uses a unique subset of acyl-CoAs for ceramide synthesis. The CerSs are part of a larger gene family, the Tram-Lag-CLN8 domain family. Here, we identify a unique, C-terminal motif, the DxRSDxE motif, which is only found in CerSs and not in other Tram-Lag-CLN8 family members. Deletion of this motif in either CerS2 or in CerS6 did not affect the ability of either enzyme to generate ceramide using both an in vitro assay and metabolic labeling, but deletion of this motif did affect the activity of CerS2 when coexpressed with CerS6. Surprisingly, transfection of cells with either CerS2 or CerS6 lacking the motif did not result in changes in cellular ceramide levels. We found that CerS2 and CerS6 interact with each other, as shown by immunoprecipitation, but deletion of the DxRSDxE motif impeded this interaction. Moreover, proteomics analysis of cells transfected with CerS6Δ338-344 indicated that deletion of the C-terminal motif impacted cellular protein expression, and in particular, the levels of ORMDL1, a negative regulator of sphingolipid synthesis. We suggest that this novel C-terminal motif regulates CerS dimer formation and thereby impacts ceramide synthesis.
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Ceramidas , Esfingosina N-Aciltransferase , Acil Coenzima A/metabolismo , Animais , Ceramidas/metabolismo , Humanos , Mamíferos , Proteômica , Esfingosina N-Aciltransferase/genética , Esfingosina N-Aciltransferase/metabolismoRESUMO
Dihydroceramide is a lipid molecule generated via the action of (dihydro)ceramide synthases (CerSs), which use two substrates, namely sphinganine and fatty acyl-CoAs. Sphinganine is generated via the sequential activity of two integral membrane proteins located in the endoplasmic reticulum. Less is known about the source of the fatty acyl-CoAs, although a number of cytosolic proteins in the pathways of acyl-CoA generation modulate ceramide synthesis via direct or indirect interaction with the CerSs. In this study, we demonstrate, by proteomic analysis of immunoprecipitated proteins, that fatty acid transporter protein 2 (FATP2) (also known as very long-chain acyl-CoA synthetase) directly interacts with CerS2 in mouse liver. Studies in cultured cells demonstrated that other members of the FATP family can also interact with CerS2, with the interaction dependent on both proteins being catalytically active. In addition, transfection of cells with FATP1, FATP2, or FATP4 increased ceramide levels although only FATP2 and 4 increased dihydroceramide levels, consistent with their known intracellular locations. Finally, we show that lipofermata, an FATP2 inhibitor which is believed to directly impact tumor cell growth via modulation of FATP2, decreased de novo dihydroceramide synthesis, suggesting that some of the proposed therapeutic effects of lipofermata may be mediated via (dihydro)ceramide rather than directly via acyl-CoA generation. In summary, our study reinforces the idea that manipulating the pathway of fatty acyl-CoA generation will impact a wide variety of down-stream lipids, not least the sphingolipids, which utilize two acyl-CoA moieties in the initial steps of their synthesis.
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Ceramidas , Coenzima A Ligases , Esfingosina N-Aciltransferase , Acil Coenzima A/metabolismo , Animais , Ceramidas/biossíntese , Fígado/metabolismo , Camundongos , Oxirredutases/metabolismo , Proteômica , Esfingosina N-Aciltransferase/metabolismoRESUMO
Oncogenic multidrug resistance is commonly intrinsic to renal cancer based on the physiological expression of detoxification transporters, particularly ABCB1, thus hampering chemotherapy. ABCB1 activity is directly dependent on its lipid microenvironment, localizing to cholesterol- and sphingomyelin (SM)-rich domains. As ceramides are the sole source for SMs, we hypothesized that ceramide synthase (CerS)-derived ceramides regulate ABCB1 activity. Using data from RNA-Seq databases, we found that patient kidney tumors exhibited increased CerS2 mRNA, which was inversely correlated with CerS6 mRNA in ABCB1+ clear cell carcinomas. Endogenous elevated CerS2 and lower CerS5/6 mRNA and protein resulted in disproportionately higher CerS2 to CerS5/6 activities (approximately twofold) in chemoresistant ABCB1high (A498, Caki-1) compared with chemosensitive ABCB1low (ACHN, normal human proximal convoluted tubule cell) cells. In addition, lipidomics analyses by HPLC-MS/MS showed bias toward CerS2-associated C20:0/C20:1-ceramides compared with CerS5/6-associated C14:0/C16:0-ceramides (2:1). SMs were similarly altered. We demonstrated that chemoresistance to doxorubicin in ABCB1high cells was partially reversed by inhibitors of de novo ceramide synthesis (l-cycloserine) and CerS (fumonisin B1) in cell viability assays. Downregulation of CerS2/6, but not CerS5, attenuated ABCB1 mRNA, protein, plasma membrane localization, rhodamine 123+ efflux transport activity, and doxorubicin resistance. Similar findings were observed with catalytically inactive CerS6-H212A. Furthermore, CerS6-targeting siRNA shifted ceramide and SM composition to ultra long-chain species (C22-C26). Inhibitors of endoplasmic reticulum-associated degradation (eeyarestatin I) and the proteasome (MG132, bortezomib) prevented ABCB1 loss induced by CerS2/6 downregulation. We conclude that a critical balance in ceramide/SM species is prerequisite to ABCB1 expression and functionalization, which could be targeted to reverse multidrug resistance in renal cancers.
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Subfamília B de Transportador de Cassetes de Ligação de ATP , Neoplasias Renais , Proteínas de Membrana , Esfingolipídeos , Esfingosina N-Aciltransferase , Proteínas Supressoras de Tumor , Subfamília B de Transportador de Cassetes de Ligação de ATP/biossíntese , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Ceramidas/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Degradação Associada com o Retículo Endoplasmático , Feminino , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Masculino , Proteínas de Membrana/metabolismo , RNA Mensageiro/genética , Esfingolipídeos/metabolismo , Esfingosina N-Aciltransferase/genética , Esfingosina N-Aciltransferase/metabolismo , Espectrometria de Massas em Tandem , Microambiente TumoralRESUMO
BACKGROUND: Genome-wide dysregulation of CpG methylation accompanies tumor progression and characteristic states of cancer cells, prompting a rationale for biomarker development. Understanding how the archetypic epigenetic modification determines systemic contributions of immune cell types is the key to further clinical benefits. RESULTS: In this study, we characterized the differential DNA methylome landscapes of peripheral blood mononuclear cells (PBMCs) from 76 canines using methylated CpG-binding domain sequencing (MBD-seq). Through gene set enrichment analysis, we discovered that genes involved in the growth and differentiation of T- and B-cells are highly methylated in tumor PBMCs. We also revealed the increased methylation at single CpG resolution and reversed expression in representative marker genes regulating immune cell proliferation (BACH2, SH2D1A, TXK, UHRF1). Furthermore, we utilized the PBMC methylome to effectively differentiate between benign and malignant tumors and the presence of mammary gland tumors through a machine-learning approach. CONCLUSIONS: This research contributes to a better knowledge of the comprehensive epigenetic regulation of circulating immune cells responding to tumors and suggests a new framework for identifying benign and malignant cancers using genome-wide methylome.
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Epigênese Genética , Neoplasias , Animais , Cães , Metilação de DNA , Epigenoma , Leucócitos Mononucleares/metabolismo , Neoplasias/genética , Biomarcadores/metabolismo , Ilhas de CpGRESUMO
BACKGROUND: Atopic dermatitis (AD) is a complex condition characterized by impaired epithelial barriers and dysregulated immune cells. In this study, we demonstrated Forsythia velutina Nakai extract (FVE) simultaneously inhibits basophils, macrophages, keratinocytes, and T cells that are closely interrelated in AD development. METHODS: We analyzed the effect of FVE on nitric oxide and reactive oxygen species (ROS) production in macrophages, basophil degranulation, T cell activation, and tight junctions in damaged keratinocytes. Expression of cell-type-specific inflammatory mediators was analyzed, and the underlying signaling pathways for anti-inflammatory effects of FVE were investigated. The anti-inflammatory effects of FVE were validated using a DNCB-induced mouse model of AD. Anti-inflammatory activity of compounds isolated from FVE was validated in each immune cell type. RESULTS: FVE downregulated the expression of inflammatory mediators and ROS production in macrophages through TLR4 and NRF2 pathways modulation. It significantly reduced basophil degranulation and expression of type 2 (T2) and pro-inflammatory cytokines by perturbing FcεRI signaling. Forsythia velutina Nakai extract also robustly inhibited the expression of T2 cytokines in activated T cells. Furthermore, FVE upregulated the expression of tight junction molecules in damaged keratinocytes and downregulated leukocyte attractants, as well as IL-33, an inducer of T2 inflammation. In the AD mouse model, FVE showed superior improvement in inflammatory cell infiltration and skin structure integrity compared to dexamethasone. Dimatairesinol, a lignan dimer, was identified as the most potent anti-inflammatory FVE compound. CONCLUSION: Forsythia velutina Nakai extract and its constituent compounds demonstrate promising efficacy as a therapeutic option for prolonged AD treatment by independently inhibiting various cell types associated with AD and disrupting the deleterious link between them.
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Patellofemoral pain and instability are common indications for imaging that are encountered in everyday practice. The authors comprehensively review key aspects of patellofemoral instability pertinent to radiologists that can be seen before the onset of osteoarthritis, highlighting the anatomy, clinical evaluation, diagnostic imaging, and treatment. Regarding the anatomy, the medial patellofemoral ligament (MPFL) is the primary static soft-tissue restraint to lateral patellar displacement and is commonly reconstructed surgically in patients with MPFL dysfunction and patellar instability. Osteoarticular abnormalities that predispose individuals to patellar instability include patellar malalignment, trochlear dysplasia, and tibial tubercle lateralization. Clinically, patients with patellar instability may be divided into two broad groups with imaging findings that sometimes overlap: patients with a history of overt patellar instability after a traumatic event (eg, dislocation, subluxation) and patients without such a history. In terms of imaging, radiography is generally the initial examination of choice, and MRI is the most common cross-sectional examination performed preoperatively. For all imaging techniques, there has been a proliferation of published radiologic measurement methods. The authors summarize the most common validated measurements for patellar malalignment, trochlear dysplasia, and tibial tubercle lateralization. Given that static imaging is inherently limited in the evaluation of patellar motion, dynamic imaging with US, CT, or MRI may be requested by some surgeons. The primary treatment strategy for patellofemoral pain is conservative. Surgical treatment options include MPFL reconstruction with or without osseous corrections such as trochleoplasty and tibial tubercle osteotomy. Postoperative complications evaluated at imaging include patellar fracture, graft failure, graft malposition, and medial patellar subluxation. ©RSNA, 2023 Quiz questions for this article are available in the supplemental material.
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Luxações Articulares , Instabilidade Articular , Luxação Patelar , Articulação Patelofemoral , Síndrome da Dor Patelofemoral , Humanos , Luxação Patelar/diagnóstico por imagem , Luxação Patelar/cirurgia , Luxação Patelar/complicações , Articulação Patelofemoral/diagnóstico por imagem , Articulação Patelofemoral/cirurgia , Estudos Transversais , Síndrome da Dor Patelofemoral/complicações , Ligamentos Articulares/cirurgiaRESUMO
Light detection and ranging (LiDAR) is widely used in autonomous vehicles to obtain precise 3D information about surrounding road environments. However, under bad weather conditions, such as rain, snow, and fog, LiDAR-detection performance is reduced. This effect has hardly been verified in actual road environments. In this study, tests were conducted with different precipitation levels (10, 20, 30, and 40 mm/h) and fog visibilities (50, 100, and 150 m) on actual roads. Square test objects (60 × 60 cm2) made of retroreflective film, aluminum, steel, black sheet, and plastic, commonly used in Korean road traffic signs, were investigated. Number of point clouds (NPC) and intensity (reflection value of points) were selected as LiDAR performance indicators. These indicators decreased with deteriorating weather in order of light rain (10-20 mm/h), weak fog (<150 m), intense rain (30-40 mm/h), and thick fog (≤50 m). Retroreflective film preserved at least 74% of the NPC under clear conditions with intense rain (30-40 mm/h) and thick fog (<50 m). Aluminum and steel showed non-observation for distances of 20-30 m under these conditions. ANOVA and post hoc tests suggested that these performance reductions were statistically significant. Such empirical tests should clarify the LiDAR performance degradation.
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The Medical Internet-of-Things (MIoT) has developed revolutionary ways of delivering medical care to patients. An example system, showing increasing demand, is the artificial pancreas system that offers convenience and reliable support care to patients with Type 1 Diabetes. Despite the apparent benefits, the system cannot escape potential cyber threats that may worsen a patient's condition. The security risks need immediate attention to ensure the privacy of the patient and preserve safe functionality. Motivated by this, we proposed a security protocol for the APS environment wherein support to essential security requirements is guaranteed, the security context negotiation is resource-friendly, and the protocol is resilient to emergencies. Accordingly, the security requirements and correctness of the design protocol were formally verified using BAN logic and AVISPA, and proved its feasibility through the emulation of APS in a controlled environment using commercial off-the-shelf devices. Moreover, the results of our performance analysis indicate that the proposed protocol is more efficient than the other existing works and standards.
Assuntos
Internet das Coisas , Pâncreas Artificial , Humanos , Segurança Computacional , PrivacidadeRESUMO
Amyloid-ß (Aß) in the form of neurotoxic aggregates is regarded as the main pathological initiator and key therapeutic target of Alzheimer's disease. However, anti-Aß drug development has been impeded by the lack of a target needed for structure-based drug design and low permeability of the blood-brain barrier (BBB). An attractive therapeutic strategy is the development of amyloid-based anti-Aß peptidomimetics that exploit the self-assembling nature of Aß and penetrate the BBB. Herein, we designed a dimeric peptide drug candidate based on the N-terminal fragment of Aß, DAB, found to cross the BBB and solubilize Aß oligomers and fibrils. Administration of DAB reduced amyloid burden in 5XFAD mice, and downregulated neuroinflammation and prevented memory impairment in the Y-maze test. Peptide mapping assays and molecular docking studies were utilized to elucidate DAB-Aß interaction. To further understand the active regions of DAB, we assessed the dissociative activity of DAB with sequence modifications.
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Doença de Alzheimer , Disfunção Cognitiva , Camundongos , Animais , Simulação de Acoplamento Molecular , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/química , Amiloide , Disfunção Cognitiva/tratamento farmacológico , Camundongos TransgênicosRESUMO
BACKGROUND AND OBJECTIVES: The recent de-escalation of care for differentiated thyroid cancer (DTC) has broadened the range of initial treatment options. We examined the association between physicians' perception of risk and their management of DTC. METHODS: Thyroid specialists were surveyed with four clinical vignettes: (1) indeterminate nodule (2) tall cell variant papillary thyroid cancer (PTC), (3) papillary thyroid microcarcinoma (mPTC), and (4) classic PTC. Participants judged the operative risks and likelihood of structural cancer recurrence associated with more versus less aggressive treatments. A logistic mixed effect model was used to predict treatment choice. RESULTS: Among 183 respondents (13.4% response rate), 44% were surgical and 56% medical thyroid specialists. Risk estimates and treatment recommendation varied markedly in each case. Respondents' estimated risk of 10-year cancer recurrence after lobectomy for a 2.0-cm PTC ranged from 1% to 53% (interquartile range [IQR]: 3%-12%), with 66% recommending lobectomy and 34% total thyroidectomy. Respondents' estimated 5-year risk of metastastic disease during active surveillance of an 0.8-cm mPTC ranged from 0% to 95% (IQR: 4%-15%), with 36% choosing active surveillance. Overall, differences in perceived risk reduction explained 10.3% of the observed variance in decision-making. CONCLUSIONS: Most of the variation in thyroid cancer treatment aggressiveness is unrelated to perceived risk of cancer recurrence.
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Carcinoma Papilar , Neoplasias da Glândula Tireoide , Carcinoma Papilar/patologia , Carcinoma Papilar/cirurgia , Humanos , Percepção , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/cirurgia , TireoidectomiaRESUMO
We provide the first estimates of the impacts of prenatal exposure to extreme temperatures on infant health at birth using the latest national birth data from 2009 to 2018 from all U.S. states. We consistently find that an additional day with mean temperature greater than 80°F or less than 10°F increases preterm births and low birthweight. Strikingly, the adverse effects are borne disproportionately by Black and Hispanic mothers, suggesting that the projected increase in extreme temperatures may further exacerbate the existing birth health disparities across different race/ethnicity groups. We also contribute by investigating the impact of deviations from the normal weather pattern, to identify the extreme weather events after accounting for the adaptation response. We find that prenatal exposure to extreme heat two standard deviations above county's historic average induces preterm births and NICU admissions, particularly for mothers whose pregnancies overlap with summer months. These results are timely and policy relevant, considering the recent weather trends with rising temperatures and frequent extreme weather events.
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Nascimento Prematuro , Efeitos Tardios da Exposição Pré-Natal , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Temperatura , Estados Unidos/epidemiologiaRESUMO
BACKGROUND: The pupillary dilation reflex (PDR), the change in pupil size after a nociceptive stimulus, has been used to assess antinociception during anesthesia. The aim of this study was to compare the antinociceptive properties of sevoflurane and desflurane by measuring the PDR amplitude. METHODS: Seventy patients between 20 and 55 years of age were randomly allocated to receive either sevoflurane or desflurane. The PDR amplitude after an electrical standardized noxious stimulation (SNT) was measured using an infrared pupillometer under 1.0 minimum alveolar concentration (MAC). The pupil diameter was measured from 5 seconds before to 5 minutes after the SNT. The mean arterial pressure (MAP), heart rate (HR), and bispectral index (BIS) were also measured immediately before and after SNT as well as 1 minute and 5 minutes after SNT. The primary outcome was the maximum percent increase from the prestimulation value of the pupil diameter, and the secondary outcomes were the maximum percent increase from the prestimulation value of the MAP, HR, and BIS after SNT. RESULTS: The maximum percent increase of the pupil diameter after SNT was not different between the 2 groups (median [first quartile to third quartile], 45.1 [29.3-80.3] vs 43.4 [27.0-103.1]; median difference, -0.3 [95% confidence interval, -16.0 to 16.5]; P = .986). Before SNT, the MAP was higher under 1.0 MAC of sevoflurane than desflurane; however, the maximum percent increase of MAP, HR, and BIS was not different between the 2 groups. CONCLUSIONS: The amount of change in the PDR amplitude, MAP, and HR after SNT was not different between sevoflurane and desflurane anesthesia. This result might suggest that sevoflurane and desflurane may not have different antinociceptive properties at equivalent MAC.
Assuntos
Anestésicos Inalatórios , Isoflurano , Éteres Metílicos , Analgésicos/farmacologia , Anestésicos Inalatórios/farmacologia , Desflurano/farmacologia , Dilatação , Humanos , Isoflurano/farmacologia , Éteres Metílicos/farmacologia , Reflexo Pupilar , Sevoflurano/farmacologiaRESUMO
BACKGROUND: External beam radiation therapy (EBRT) is rarely used to treat patients with differentiated or medullary thyroid cancer. Although EBRT is generally administered to patients with high-risk or unresectable diseases, neither its indications for the use nor the associated outcomes are well-defined. We used a statewide cohort to assess the trends in EBRT use and postradiation outcomes in California. METHODS: A population-based study of patients within the California Cancer Registry who underwent EBRT after surgery for nonanaplastic thyroid cancer (2003-2017) was conducted. The primary outcome was the annual utilization rate of EBRT. The secondary outcomes included Kaplan-Meier analysis for cause-specific survival and identifying factors associated with improved survival after EBRT. RESULTS: Among the 57 607 patients with nonanaplastic thyroid cancer from 2003 to 2017, 344 (0.6%) patients received EBRT. EBRT was utilized in 0.4% of papillary, 1.1% of follicular, and 7.7% of medullary thyroid cancers in California. Overall, 99 (28.8%) patients treated with EBRT died of thyroid cancer. The 10-year cause-specific survival of all patients with thyroid cancer after EBRT was 61.5% (95% CI: 54.8%-69.1%) and that of patients without distant disease was 80.3% (95% CI: 73.5%-87.8%). The survival outcomes varied by tumor size, histology, disease stage, patient age at diagnosis, and the presence of extrathyroidal extension (P < .05). CONCLUSIONS: The use of adjuvant EBRT for nonanaplastic thyroid cancer remained stable and low in California from 2003 to 2017. The comparative efficacy of EBRT was not discernible in this study, but disease control appeared durable in select patients. Well-controlled observational studies and/or prospective studies are needed to better define which patients benefit from EBRT.
Assuntos
Carcinoma Neuroendócrino , Neoplasias da Glândula Tireoide , California/epidemiologia , Humanos , Estimativa de Kaplan-Meier , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgiaRESUMO
In this study, we examined whether aortic contraction, induced by the alpha-2 adrenoceptor agonist dexmedetomidine, is involved in the transactivation of the epidermal growth factor receptor (EGFR) in isolated endothelium-denuded rat aortas. Additionally, we aimed to elucidate the associated underlying cellular mechanisms. The effects of the alpha-2 adrenoceptor inhibitor rauwolscine, EGFR tyrosine kinase inhibitor AG1478, Src kinase inhibitors PP1 and PP2, and matrix metalloproteinase inhibitor GM6001 on EGFR tyrosine phosphorylation and c-Jun NH2-terminal kinase (JNK) phosphorylation induced by dexmedetomidine in rat aortic smooth muscles were examined. In addition, the effects of these inhibitors on dexmedetomidine-induced contraction in isolated endothelium-denuded rat aorta were examined. Dexmedetomidine-induced contraction was inhibited by the alpha-1 adrenoceptor inhibitor prazosin, rauwolscine, AG1478, PP1, PP2, and GM6001 alone or by a combined treatment with prazosin and AG1478. AG1478 (3 × 10-6 M) inhibited dexmedetomidine-induced contraction in isolated endothelium-denuded rat aortas pretreated with rauwolscine. Dexmedetomidine-induced EGFR tyrosine and JNK phosphorylation were inhibited by rauwolscine, PP1, PP2, GM6001, and AG1478. Furthermore, dexmedetomidine-induced JNK phosphorylation reduced upon EGFR siRNA treatment. Therefore, these results suggested that the transactivation of EGFR associated with dexmedetomidine-induced contraction, mediated by the alpha-2 adrenoceptor, Src kinase, and matrix metalloproteinase, caused JNK phosphorylation and increased calcium levels.