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1.
Nature ; 579(7798): 303-308, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31945771

RESUMO

Arrestin proteins bind to active, phosphorylated G-protein-coupled receptors (GPCRs), thereby preventing G-protein coupling, triggering receptor internalization and affecting various downstream signalling pathways1,2. Although there is a wealth of structural information detailing the interactions between GPCRs and G proteins, less is known about how arrestins engage GPCRs. Here we report a cryo-electron microscopy structure of full-length human neurotensin receptor 1 (NTSR1) in complex with truncated human ß-arrestin 1 (ßarr1(ΔCT)). We find that phosphorylation of NTSR1 is critical for the formation of a stable complex with ßarr1(ΔCT), and identify phosphorylated sites in both the third intracellular loop and the C terminus that may promote this interaction. In addition, we observe a phosphatidylinositol-4,5-bisphosphate molecule forming a bridge between the membrane side of NTSR1 transmembrane segments 1 and 4 and the C-lobe of arrestin. Compared with a structure of a rhodopsin-arrestin-1 complex, in our structure arrestin is rotated by approximately 85° relative to the receptor. These findings highlight both conserved aspects and plasticity among arrestin-receptor interactions.


Assuntos
Modelos Moleculares , Receptores de Neurotensina/química , beta-Arrestina 1/química , Microscopia Crioeletrônica , Humanos , Fosforilação , Estabilidade Proteica , Estrutura Quaternária de Proteína , Receptores de Neurotensina/metabolismo , beta-Arrestina 1/metabolismo
2.
Nature ; 588(7839): 670-675, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33238290

RESUMO

The distal lung contains terminal bronchioles and alveoli that facilitate gas exchange. Three-dimensional in vitro human distal lung culture systems would strongly facilitate the investigation of pathologies such as interstitial lung disease, cancer and coronavirus disease 2019 (COVID-19) pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here we describe the development of a long-term feeder-free, chemically defined culture system for distal lung progenitors as organoids derived from single adult human alveolar epithelial type II (AT2) or KRT5+ basal cells. AT2 organoids were able to differentiate into AT1 cells, and basal cell organoids developed lumens lined with differentiated club and ciliated cells. Single-cell analysis of KRT5+ cells in basal organoids revealed a distinct population of ITGA6+ITGB4+ mitotic cells, whose offspring further segregated into a TNFRSF12Ahi subfraction that comprised about ten per cent of KRT5+ basal cells. This subpopulation formed clusters within terminal bronchioles and exhibited enriched clonogenic organoid growth activity. We created distal lung organoids with apical-out polarity to present ACE2 on the exposed external surface, facilitating infection of AT2 and basal cultures with SARS-CoV-2 and identifying club cells as a target population. This long-term, feeder-free culture of human distal lung organoids, coupled with single-cell analysis, identifies functional heterogeneity among basal cells and establishes a facile in vitro organoid model of human distal lung infections, including COVID-19-associated pneumonia.


Assuntos
COVID-19/virologia , Pulmão/citologia , Modelos Biológicos , Organoides/citologia , Organoides/virologia , SARS-CoV-2/fisiologia , Técnicas de Cultura de Tecidos , Células Epiteliais Alveolares/citologia , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/virologia , COVID-19/metabolismo , COVID-19/patologia , Diferenciação Celular , Divisão Celular , Células Clonais/citologia , Células Clonais/metabolismo , Células Clonais/virologia , Humanos , Técnicas In Vitro , Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Vírus da Influenza A Subtipo H1N1/fisiologia , Integrina alfa6/análise , Integrina beta4/análise , Queratina-5/análise , Organoides/metabolismo , Pneumonia Viral/metabolismo , Pneumonia Viral/patologia , Pneumonia Viral/virologia , SARS-CoV-2/crescimento & desenvolvimento , Análise de Célula Única , Receptor de TWEAK/análise
3.
Nano Lett ; 24(25): 7557-7563, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38758657

RESUMO

Ultrathin topological insulator membranes are building blocks of exotic quantum matter. However, traditional epitaxy of these materials does not facilitate stacking in arbitrary orders, while mechanical exfoliation from bulk crystals is also challenging due to the non-negligible interlayer coupling therein. Here we liberate millimeter-scale films of the topological insulator Bi2Se3, grown by molecular beam epitaxy, down to 3 quintuple layers. We characterize the preservation of the topological surface states and quantum well states in transferred Bi2Se3 films using angle-resolved photoemission spectroscopy. Leveraging the photon-energy-dependent surface sensitivity, the photoemission spectra taken with 6 and 21.2 eV photons reveal a transfer-induced migration of the topological surface states from the top to the inner layers. By establishing clear electronic structures of the transferred films and unveiling the wave function relocation of the topological surface states, our work lays the physics foundation crucial for the future fabrication of artificially stacked topological materials with single-layer precision.

4.
Curr Opin Hematol ; 31(3): 122-129, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38359323

RESUMO

PURPOSE OF REVIEW: This review summarizes recent advances in developing targeted diagnostics for venous thromboembolism (VTE) and unaddressed knowledge gaps in patient management. Without addressing these critical data needs, the morbidity in VTE patients will persist. RECENT FINDINGS: Recent studies investigating plasma protein profiles in VTE patients have identified key diagnostic targets to address the currently unmet need for low-cost, confirmatory, point-of-care VTE diagnostics. These studies and a growing body of evidence from animal model studies have revealed the importance of inflammatory and vascular pathology in driving VTE, which are currently unaddressed targets for VTE therapy. To enhance the translation of preclinical animal studies, clinical quantification of thrombus burden and comparative component analyses between modeled VTE and clinical VTE are necessary. SUMMARY: Lead candidates from protein profiling of VTE patients' plasma offer a promising outlook in developing low cost, confirmatory, point-of-care testing for VTE. Additionally, addressing the critical knowledge gap of quantitatively measuring clinical thrombi will allow for an array of benefits in VTE management and informing the translatability of experimental therapeutics.


Assuntos
Tromboembolia Venosa , Trombose Venosa , Humanos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/tratamento farmacológico , Anticoagulantes/uso terapêutico
5.
Opt Lett ; 49(8): 2025-2028, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621067

RESUMO

The alignment of a receiver with a pencil beam in a wireless optical power transfer (WOPT) system employing a resonance beam charging (RBC) technology limits the establishment of a resonance cavity. Accurate tracking necessitates precise and dependable monitoring, which requires the exact placement of transmitting and receiving devices. Herein, we present a concept of a two-dimensional (2D) beam steering mechanism for RBC-based WOPT systems utilizing dispersed laser beams. The proposed approach allows a significant improvement, including reduction of scanning times and minimization of errors, in relation to conventional pencil-beam-based systems. Experimental results reveal 14% faster acquisition time efficiency, an 18% improvement in pointing accuracy, and a 24% enhancement in tracking accuracy. These results establish the prerequisites for the implementation of dispersed beam steering in the RBC-based WOPT system. This capability empowers the system to charge movable devices and Internet of Things devices consistently in smart factories.

6.
Platelets ; 35(1): 2290916, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38099327

RESUMO

Platelets are core components of thrombi but their effect on thrombus burden during deep vein thrombosis (DVT) has not been fully characterized. We examined the role of thrombopoietin-altered platelet count on thrombus burden in a murine stasis model of DVT. To modulate platelet count compared to baseline, CD1 mice were pretreated with thrombopoietin antisense oligonucleotide (THPO-ASO, 56% decrease), thrombopoietin mimetic (TPO-mimetic, 36% increase), or saline (within 1%). Thrombi and vein walls were examined on postoperative days (POD) 3 and 7. Thrombus weights on POD 3 were not different between treatment groups (p = .84). The mean thrombus weights on POD 7 were significantly increased in the TPO-mimetic cohort compared to the THPO-ASO (p = .005) and the saline (p = .012) cohorts. Histological grading at POD 3 revealed a significantly increased smooth muscle cell presence in the thrombi and CD31 positive channeling in the vein wall of the TPO-mimetic cohort compared to the saline and THPO-ASO cohorts (p < .05). No differences were observed in histology on POD 7. Thrombopoietin-induced increased platelet count increased thrombus weight on POD 7 indicating platelet count may regulate thrombus burden during early resolution of venous thrombi in this murine stasis model of DVT.


Deep vein thrombosis (DVT) is a pathology in which blood clots form in the deep veins of our body. Usually occurring in the legs, these clots can be dangerous if they dislodge and travel to the heart and are pumped into the lungs. Often these clots do not travel and heal where they formed. However, as the body heals the clot it may also cause damage to the vein wall and predispose the patient to future clots, i.e., the biggest risk factor for a second clot is the first clot. DVT can also cause symptoms of pain, swelling, and redness in the long-term, leading to post-thrombotic syndrome where the initial symptoms of the clot persist for a long time. All blood clots have common components of red blood cells, white blood cells, platelets, and fibrin in varying concentrations. Humans maintain a platelet count between 150 and 400 thousand platelets per microliter of our blood. However, diseases like cancer or medications like chemotherapy can cause a change in our body's platelet count. The effect of a changing platelet count on the size (clot burden) of DVT clot and how platelet count could affect DVT as the clot heals is not fully understood. Studying this might help us develop better targets and treat patients with a wide range of platelet counts who experience DVT. In this study, we intentionally decreased, left unchanged, and increased platelet counts in mice and then created a DVT to study what the effect of low, normal, and high platelet counts, respectively, would be on the clot burden. We observed that mice with higher platelet counts had a higher clot burden during the early part of the healing process of the clot. Within this study, we can conclude that higher platelet counts may lead to higher clot burden in DVT which furthers our understanding of how platelet count affects clot burden during DVT.


Assuntos
Trombose , Trombose Venosa , Humanos , Camundongos , Animais , Trombose Venosa/tratamento farmacológico , Trombose Venosa/patologia , Contagem de Plaquetas , Trombopoetina/farmacologia , Plaquetas/patologia
7.
Proc Natl Acad Sci U S A ; 118(1)2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33443159

RESUMO

Inositol-1,4,5-triphosphate (IP3) kinase B (ITPKB) is a ubiquitously expressed lipid kinase that inactivates IP3, a secondary messenger that stimulates calcium release from the endoplasmic reticulum (ER). Genome-wide association studies have identified common variants in the ITPKB gene locus associated with reduced risk of sporadic Parkinson's disease (PD). Here, we investigate whether ITPKB activity or expression level impacts PD phenotypes in cellular and animal models. In primary neurons, knockdown or pharmacological inhibition of ITPKB increased levels of phosphorylated, insoluble α-synuclein pathology following treatment with α-synuclein preformed fibrils (PFFs). Conversely, ITPKB overexpression reduced PFF-induced α-synuclein aggregation. We also demonstrate that ITPKB inhibition or knockdown increases intracellular calcium levels in neurons, leading to an accumulation of calcium in mitochondria that increases respiration and inhibits the initiation of autophagy, suggesting that ITPKB regulates α-synuclein pathology by inhibiting ER-to-mitochondria calcium transport. Furthermore, the effects of ITPKB on mitochondrial calcium and respiration were prevented by pretreatment with pharmacological inhibitors of the mitochondrial calcium uniporter complex, which was also sufficient to reduce α-synuclein pathology in PFF-treated neurons. Taken together, these results identify ITPKB as a negative regulator of α-synuclein aggregation and highlight modulation of ER-to-mitochondria calcium flux as a therapeutic strategy for the treatment of sporadic PD.


Assuntos
Cálcio/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , alfa-Sinucleína/metabolismo , Animais , Autofagia/genética , Retículo Endoplasmático/metabolismo , Estudo de Associação Genômica Ampla/métodos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Neurônios/metabolismo , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fosforilação/genética , Transdução de Sinais/genética , Sinucleinopatias/genética , Sinucleinopatias/metabolismo
8.
Psychol Health Med ; : 1-18, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700271

RESUMO

Antibiotic resistance (AR) rates in Vietnam are among the highest in Asia, and recent infections due to multi-drug resistance in the country have caused thousands of deaths each year. This study investigated a Vietnamese community's preferences for antibiotic treatment and its knowledge and attitudes regarding antibiotics. A discrete choice experiment-based survey was developed and administered to the population of interest. The respondents were given sociodemographic-, knowledge- and attitude-related items and 17 pairs of choice tasks. Two hypothetical options were included in each choice task. Latent class analysis was conducted to determine the differences among the respondents' preferences. Among 1,014 respondents, 805 (79.4%) gave valid questionnaires. A three-latent-class model with four covariates (age, healthcare-related education or career, occupation, and attitude classifications) was used in the analysis. All five attributes significantly influenced the respondents' decisions. The majority, including young employed respondents with non-healthcare-related work or education, found treatment failure more important. Older respondents who had healthcare-related education/careers and/or appropriate antibiotic use- and antibiotics resistance-related attitudes, regarded contribution to antibiotic resistance as an important attribute in selecting antibiotic treatments. Unemployed individuals with correct knowledge identified the cost of antibiotic treatment as the most essential decision-making factor. Findings suggest minimal antibiotic impact on resistance; only 7.83% view it as amajor concern. The respondents exhibited substantial preference heterogeneity, and the general Vietnamese public had poor knowledge of and attitudes toward antibiotic use and antibiotic resistance. This study emphasizes the need for individual responsibility for antibiotic resistance and appropriate antibiotic use.

9.
Biophys J ; 122(1): 168-179, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36352784

RESUMO

The functional properties of proteorhodopsin (PR) have been found to be strongly modulated by oligomeric distributions and lipid membrane mimetics. This study aims to distinguish and explain their effects by investigating how oligomer formation impacts PR's function of proton transport in lipid-based membrane mimetic environments. We find that PR forms stable hexamers and pentamers in both E. coli membranes and synthetic liposomes. Compared with the monomers, the photocycle kinetics of PR oligomers is ∼2 and ∼4.5 times slower for transitions between the K and M and the M and N photointermediates, respectively, indicating that oligomerization significantly slows PR's rate of proton transport in liposomes. In contrast, the apparent pKa of the key proton acceptor residue D97 (pKaD97) of liposome-embedded PR persists at 6.2-6.6, regardless of cross-protomer modulation of D97, suggesting that the liposome environment helps maintain PR's functional activity at neutral pH. By comparison, when extracted directly from E. coli membranes into styrene-maleic acid lipid particles, the pKaD97 of monomer-enriched E50Q PR drastically increases to 8.9, implying that there is a very low active PR population at neutral pH to engage in PR's photocycle. These findings demonstrate that oligomerization impacts PR's photocycle kinetics, while lipid-based membrane mimetics strongly affect PR's active population via different mechanisms.


Assuntos
Escherichia coli , Lipossomos , Prótons , Rodopsinas Microbianas/química , Lipídeos
10.
Biochemistry ; 62(11): 1589-1593, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37184546

RESUMO

Fragment antigen-binding domains of antibodies (Fabs) are powerful probes of structure-function relationships of assembly line polyketide synthases (PKSs). We report the discovery and characterization of Fabs interrogating the structure and function of the ketosynthase-acyltransferase (KS-AT) core of Module 2 of the 6-deoxyerythronolide B synthase (DEBS). Two Fabs (AC2 and BB1) were identified to potently inhibit the catalytic activity of Module 2. Both AC2 and BB1 were found to modulate ACP-mediated reactions catalyzed by this module, albeit by distinct mechanisms. AC2 primarily affects the rate (kcat), whereas BB1 increases the KM of an ACP-mediated reaction. A third Fab, AA5, binds to the KS-AT fragment of DEBS Module 2 without altering either parameter; it is phenotypically reminiscent of a previously characterized Fab, 1B2, shown to principally recognize the N-terminal helical docking domain of DEBS Module 3. Crystal structures of AA5 and 1B2 bound to the KS-AT fragment of Module 2 were solved to 2.70 and 2.65 Å resolution, respectively, and revealed entirely distinct recognition features of the two antibodies. The new tools and insights reported here pave the way toward advancing our understanding of the structure-function relationships of DEBS Module 2, arguably the most well-studied module of an assembly line PKS.


Assuntos
Eritromicina , Policetídeo Sintases , Policetídeo Sintases/química , Aciltransferases/química , Anticorpos
11.
J Biol Chem ; 298(12): 102597, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36244454

RESUMO

Most eukaryotic secretory proteins are cotranslationally translocated through Sec61 into the endoplasmic reticulum (ER). Because these proteins have evolved to fold in the ER, their mistargeting is associated with toxicity. Genetic experiments have implicated the ER heat shock protein 70 (Hsp70) Hspa13/STCH as involved in processing of nascent secretory proteins. Herein, we evaluate the role of Hspa13 in protein import and the maintenance of cellular proteostasis in human cells, primarily using the human embryonic kidney 293T cell line. We find that Hspa13 interacts primarily with the Sec61 translocon and its associated factors. Hspa13 overexpression inhibits translocation of the secreted protein transthyretin, leading to accumulation and aggregation of immature transthyretin in the cytosol. ATPase-inactive mutants of Hspa13 further inhibit translocation and maturation of secretory proteins. While Hspa13 overexpression inhibits cell growth and ER quality control, we demonstrate that HSPA13 knockout destabilizes proteostasis and increases sensitivity to ER disruption. Thus, we propose that Hspa13 regulates import through the translocon to maintain both ER and cytosolic protein homeostasis. The raw mass spectrometry data associated with this article have been deposited in the PRIDE archive and can be accessed at PXD033498.


Assuntos
Proteínas de Choque Térmico , Proteostase , Humanos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Pré-Albumina/metabolismo , Citosol/metabolismo , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Transporte Proteico , Canais de Translocação SEC/metabolismo
12.
J Magn Reson Imaging ; 57(3): 740-749, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35648374

RESUMO

BACKGROUND: Timely diagnosis of meniscus injuries is key for preventing knee joint dysfunction and improving patient outcomes because it decreases morbidity and facilitates treatment planning. PURPOSE: To train and evaluate a deep learning model for automated detection of meniscus tears on knee magnetic resonance imaging (MRI). STUDY TYPE: Bicentric retrospective study. SUBJECTS: In total, 584 knee MRI studies, divided among training (n = 234), testing (n = 200), and external validation (n = 150) data sets, were used in this study. The public data set MRNet was used as a second external validation data set to evaluate the performance of the model. SEQUENCE: A 3 T, coronal, and sagittal images from T1-weighted proton density (PD) fast spin-echo (FSE) with fat saturation and T2-weighted FSE with fat saturation sequences. ASSESSMENT: The detection system for meniscus tear was based on the improved YOLOv4 model with Darknet-53 as the backbone. The performance of the model was also compared with that of three radiologists of varying levels of experience. The determination of the presence of a meniscus tear from surgery reports was used as the ground truth for the images. STATISTICAL TESTS: Sensitivity, specificity, prevalence, positive predictive value, negative predictive value, accuracy, and receiver operating characteristic curve were used to evaluate the performance of the detection model. Two-way analysis of variance, Wilcoxon signed-rank test, and Tukey's multiple tests were used to evaluate differences in performance between the model and radiologists. RESULTS: The overall accuracies for detecting meniscus tears using our model on the internal testing, internal validation, and external validation data sets were 95.4%, 95.8%, and 78.8%, respectively. One radiologist had significantly lower performance than our model in detecting meniscal tears (accuracy: 0.9025 ± 0.093 vs. 0.9580 ± 0.025). DATA CONCLUSION: The proposed model had high sensitivity, specificity, and accuracy for detecting meniscus tears on knee MRIs. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 2.


Assuntos
Menisco , Lesões do Menisco Tibial , Humanos , Estudos Retrospectivos , Meniscos Tibiais , Lesões do Menisco Tibial/diagnóstico por imagem , Lesões do Menisco Tibial/patologia , Artroscopia , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Sensibilidade e Especificidade , Redes Neurais de Computação
13.
Epidemiol Infect ; 151: e117, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37401482

RESUMO

The aim of this study is to analyse the changing patterns in the transmission of COVID-19 in relation to changes in Vietnamese governmental policies, based on epidemiological data and policy actions in a large Vietnamese province, Bac Ninh, in 2021. Data on confirmed cases from January to December 2021 were collected, together with policy documents. There were three distinct periods of the COVID-19 pandemic in Bac Ninh province during 2021. During the first period, referred to as the 'Zero-COVID' period (01/04-07/04/2021), there was a low population vaccination rate, with less than 25% of the population receiving its first vaccine dose. Measures implemented during this period focused on domestic movement restrictions, mask mandates, and screening efforts to control the spread of the virus. The subsequent period, referred to as the 'Transition' period (07/05-10/22/2021), witnessed a significant increase in population vaccination coverage, with 80% of the population receiving their first vaccine dose. During this period, several days passed without any reported COVID-19 cases in the community. The local government implemented measures to manage domestic actions and reduce the time spent in quarantine, and encouraged home quarantining for the close contacts of cases with COVID-19. Finally, the 'New-normal' stage (10/23-12/31/2021), during which the population vaccination coverage with a second vaccine dose increased to 70%, and most of the mandates for the prevention and control of COVID-19 were reduced. In conclusion, this study highlights the importance of governmental policies in managing and controlling the transmission of COVID-19 and provides insights for developing realistic and context-specific strategies in similar settings.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Quarentena , SARS-CoV-2 , Vietnã/epidemiologia
14.
J Nat Prod ; 86(9): 2145-2150, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37610630

RESUMO

Ten new norterpene alkaloids, coscinoderines A-J (1-10), were isolated from the marine sponge Coscinoderma bakusi. Each coscinoderine contains a 1,2,5-trisubstituted pyridinium moiety bearing a terpene unit at the C-2 position. Their structures were elucidated by analysis of NMR and HRMS data, and the absolute stereochemistry of 4 with a 2-methylbutyl group attached to the nitrogen was determined from a comparison of the calculated and measured ECD spectra. The isolation of coscinoderines expands the repertoire of pyridinium alkaloids isolated from marine sponges.


Assuntos
Alcaloides , Poríferos , Animais , Poríferos/química , Alcaloides/farmacologia , Alcaloides/química , Espectroscopia de Ressonância Magnética , Terpenos , Estrutura Molecular
15.
Artif Organs ; 47(4): 640-648, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36404709

RESUMO

BACKGROUND: Patients on continuous flow ventricular assist devices (CF-VADs) are at high risk for the development of Acquired von-Willebrand Syndrome (AVWS) and non-surgical bleeding. von Willebrand Factor (vWF) plays an essential role in maintaining hemostasis via platelet binding to the damaged endothelium to facilitate coagulation. In CF-VAD patients, degradation of vWF into low MW multimers that are inefficient in facilitating coagulation occurs and has been primarily attributed to the supraphysiological shear stress associated with the CF-VAD impeller. METHODS: In this review, we evaluate information from the literature regarding the unraveling behavior of surface-immobilized vWF under pulsatile and continuous flow pertaining to: (A) the process of arterial endothelial vWF production and release into circulation, (B) the critical shear stress required to unravel surface bound versus soluble vWF which leads to degradation, and (C) the role of pulsatility in on the production and degradation of vWF. RESULTS AND CONCLUSION: Taken together, these data suggests that the loss of pulsatility and its impact on arterial endothelial cells plays an important role in the production, release, unraveling, and proteolytic degradation of vWF into low MW multimers, contributing to the development of AVWS. Restoration of pulsatility can potentially mitigate this issue by preventing AVWS and minimizing the risk of non-surgical bleeding.


Assuntos
Coração Auxiliar , Doenças de von Willebrand , Humanos , Fator de von Willebrand/metabolismo , Coração Auxiliar/efeitos adversos , Células Endoteliais/metabolismo , Hemorragia , Endotélio/metabolismo
16.
Phytother Res ; 37(1): 140-150, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36065796

RESUMO

Huperzia serrata contains Huperzine A (HupA)-an alkaloid used to treat cognitive dysfunction. In this study, we used the total alkaloids (HsAE) to investigate their potential in managing cognitive impairment in comparison with HupA. The antioxidant activity was measured by DPPH assay. In the cellular study, the cell viability and level of ACh of SH-SY5Y cells were evaluated after pretreated with HsAE and scopolamine. For in vivo assay, mice were pre-treated with HsAE, and HupA and undergone scopolamine injection for cognitive impairment. The behavioral tests including the Y-maze and Morris water maze test and the AChE activity, the SOD, CAT, MDA level in the hippocampus and cortex were evaluated. HsAE showed significant scavenging properties on DPPH radicals. HsAE was not toxic to SH-SY5Y cells, and can rescue these cells upon scopolamine treatment. Intriguingly, HsAE showed the neuroprotection against scopolamine-induced amnesia in mice. Moreover, HsAE decreased AChE activity, MDA level, increased antioxidative enzyme activity in the hippocampus as well as cortex of mice, which was relatively better than that of HupA. These findings suggested that HsAE may significantly protect the neurons of mice with scopolamine-induced memory impairment connected to AChE depletion and oxidative stress.


Assuntos
Alcaloides , Huperzia , Neuroblastoma , Fármacos Neuroprotetores , Humanos , Camundongos , Animais , Escopolamina , Fármacos Neuroprotetores/farmacologia , Huperzia/química , Huperzia/metabolismo , Alcaloides/farmacologia , Alcaloides/química , Antioxidantes/farmacologia , Estresse Oxidativo , Acetilcolinesterase/metabolismo
17.
Sensors (Basel) ; 23(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36904587

RESUMO

This study examined the brain source space functional connectivity from the electroencephalogram (EEG) activity of 48 participants during a driving simulation experiment where they drove until fatigue developed. Source-space functional connectivity (FC) analysis is a state-of-the-art method for understanding connections between brain regions that may indicate psychological differences. Multi-band FC in the brain source space was constructed using the phased lag index (PLI) method and used as features to train an SVM classification model to classify driver fatigue and alert conditions. With a subset of critical connections in the beta band, a classification accuracy of 93% was achieved. Additionally, the source-space FC feature extractor demonstrated superiority over other methods, such as PSD and sensor-space FC, in classifying fatigue. The results suggested that source-space FC is a discriminative biomarker for detecting driving fatigue.


Assuntos
Condução de Veículo , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Encéfalo , Fadiga/diagnóstico , Simulação por Computador
18.
Sensors (Basel) ; 23(8)2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37112302

RESUMO

Possible drug-food constituent interactions (DFIs) could change the intended efficiency of particular therapeutics in medical practice. The increasing number of multiple-drug prescriptions leads to the rise of drug-drug interactions (DDIs) and DFIs. These adverse interactions lead to other implications, e.g., the decline in medicament's effect, the withdrawals of various medications, and harmful impacts on the patients' health. However, the importance of DFIs remains underestimated, as the number of studies on these topics is constrained. Recently, scientists have applied artificial intelligence-based models to study DFIs. However, there were still some limitations in data mining, input, and detailed annotations. This study proposed a novel prediction model to address the limitations of previous studies. In detail, we extracted 70,477 food compounds from the FooDB database and 13,580 drugs from the DrugBank database. We extracted 3780 features from each drug-food compound pair. The optimal model was eXtreme Gradient Boosting (XGBoost). We also validated the performance of our model on one external test set from a previous study which contained 1922 DFIs. Finally, we applied our model to recommend whether a drug should or should not be taken with some food compounds based on their interactions. The model can provide highly accurate and clinically relevant recommendations, especially for DFIs that may cause severe adverse events and even death. Our proposed model can contribute to developing more robust predictive models to help patients, under the supervision and consultants of physicians, avoid DFI adverse effects in combining drugs and foods for therapy.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Interações Alimento-Droga , Humanos , Inteligência Artificial , Aprendizado de Máquina
19.
J Clin Nurs ; 32(13-14): 3058-3073, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36168199

RESUMO

BACKGROUND: A range of psychological issues often accompany breast cancer chemotherapy. Due to their ubiquity, mobile phones have been used to deliver supportive interventions addressing these issues. However, we currently lack sufficient evidence to guide the design of such interventions. AIM: To analyse and synthesise available evidence on the effectiveness of mobile-phone-based (mHealth) interventions in alleviating the psychological issues experienced by women receiving chemotherapy for breast cancer. METHODS: A systematic literature search was conducted from 14 relevant databases. Revman 5.4 was used to pool the quantitative results from comparable studies for statistical meta-analysis. For clinically heterogeneous studies where statistical pooling of results was not possible, a narrative summary was used to present the findings. RESULTS: The review included nine RCTs which covered 1457 patients. The meta-analysis results indicated a significant improvement in the quality of life (standardised mean difference [SMD] = 0.32, 95% confidence interval [CI] [0.07, 0.58], p = .01, I2  = 17%). No significant effects were found for anxiety (SMD = -0.01, 95% CI [-0.26, 0.25], p = .96, I2  = 53%) and depression (SMD = 0.02, 95% CI [-0.17, 0.20], p = .87, I2  = 0%). Individual studies suggest reduced symptom prevalence (p = .033, d = 0.27), symptom distress (p = .004, d = 0.34), symptom interference (p = .02, d = 0.51), supportive care needs (p < .05, d = 2.43); improved self-efficacy (p = .03, d = 0.53), self-esteem (p < .001, d = 0.87) and emotional functioning (p = .008, d = 0.30). The methodological quality ranged from low to moderate. CONCLUSION: mHealth interventions might help address certain psychological issues experienced by this population, although the evidence is still being gathered and not yet conclusive. More rigorous trials are warranted to confirm the suitable duration while addressing the methodological flaws found in previous studies. PROSPERO REGISTRATION NUMBER: CRD42021224307.


Assuntos
Neoplasias da Mama , Telemedicina , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/psicologia , Qualidade de Vida , Depressão , Ansiedade , Telemedicina/métodos
20.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37685889

RESUMO

Through a unique genomics and drug screening platform with ~800 solid tumor cell lines, we have found a subset of SCLC cell lines are hypersensitive to venetoclax, an FDA-approved inhibitor of BCL-2. SCLC-A (ASCL1 positive) and SCLC-P (POU2F3 positive), which make up almost 80% of SCLC, frequently express high levels of BCL-2. We found that a subset of SCLC-A and SCLC-P showed high BCL-2 expression but were venetoclax-resistant. In addition, most of these SCLC cell lines have TP53 missense mutations, which make a single amino acid change. These mutants not only lose wild-type (WT) p53 tumor suppressor functions, but also acquire novel cancer-promoting activities (oncogenic, gain-of-function). A recent study with oncogenic mutant (Onc)-p53 knock-in mouse models of SCLC suggests gain-of-function activity can attenuate chemotherapeutic efficacy. Based on these observations, we hypothesize that Onc-p53 confers venetoclax resistance and that simultaneous inhibition of BCL-2 and Onc-p53 induces synergistic anticancer activity in a subset of SCLC-A and SCLC-P. We show here that (1) down-regulation of Onc-p53 increases the expression of a BH3-only pro-apoptotic BIM and sensitizes to venetoclax in SCLC-P cells; (2) targeting Onc-p53 by the HSP90 inhibitor, ganetespib, increases BIM expression and sensitizes to venetoclax in SCLC-P and SCLC-A cells. Although there are currently many combination studies for venetoclax proposed, the concept of simultaneous targeting of BCL-2 and Onc-p53 by the combination of venetoclax and HSP90 inhibitors would be a promising approach for SCLC treatment.


Assuntos
Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Animais , Camundongos , Linhagem Celular Tumoral , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico , Carcinoma de Pequenas Células do Pulmão/genética , Proteína Supressora de Tumor p53/genética
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