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1.
PLoS Comput Biol ; 20(5): e1011200, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38709852

RESUMO

During the COVID-19 pandemic, forecasting COVID-19 trends to support planning and response was a priority for scientists and decision makers alike. In the United States, COVID-19 forecasting was coordinated by a large group of universities, companies, and government entities led by the Centers for Disease Control and Prevention and the US COVID-19 Forecast Hub (https://covid19forecasthub.org). We evaluated approximately 9.7 million forecasts of weekly state-level COVID-19 cases for predictions 1-4 weeks into the future submitted by 24 teams from August 2020 to December 2021. We assessed coverage of central prediction intervals and weighted interval scores (WIS), adjusting for missing forecasts relative to a baseline forecast, and used a Gaussian generalized estimating equation (GEE) model to evaluate differences in skill across epidemic phases that were defined by the effective reproduction number. Overall, we found high variation in skill across individual models, with ensemble-based forecasts outperforming other approaches. Forecast skill relative to the baseline was generally higher for larger jurisdictions (e.g., states compared to counties). Over time, forecasts generally performed worst in periods of rapid changes in reported cases (either in increasing or decreasing epidemic phases) with 95% prediction interval coverage dropping below 50% during the growth phases of the winter 2020, Delta, and Omicron waves. Ideally, case forecasts could serve as a leading indicator of changes in transmission dynamics. However, while most COVID-19 case forecasts outperformed a naïve baseline model, even the most accurate case forecasts were unreliable in key phases. Further research could improve forecasts of leading indicators, like COVID-19 cases, by leveraging additional real-time data, addressing performance across phases, improving the characterization of forecast confidence, and ensuring that forecasts were coherent across spatial scales. In the meantime, it is critical for forecast users to appreciate current limitations and use a broad set of indicators to inform pandemic-related decision making.


Assuntos
COVID-19 , Previsões , Pandemias , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/transmissão , Humanos , Previsões/métodos , Estados Unidos/epidemiologia , Pandemias/estatística & dados numéricos , Biologia Computacional , Modelos Estatísticos
2.
Proc Natl Acad Sci U S A ; 119(24): e2200200119, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35675429

RESUMO

The human transferrin receptor (TFR) is overexpressed in most breast cancers, including preneoplastic ductal carcinoma in situ (DCIS). HB21(Fv)-PE40 is a single-chain immunotoxin (IT) engineered by fusing the variable region of a monoclonal antibody (HB21) against a TFR with a 40 kDa fragment of Pseudomonas exotoxin (PE). In humans, the administration of other TFR-targeted immunotoxins intrathecally led to inflammation and vascular leakage. We proposed that for treatment of DCIS, intraductal (i.duc) injection of HB21(Fv)-PE40 could avoid systemic toxicity while retaining its potent antitumor effects on visible and occult tumors in the entire ductal tree. Pharmacokinetic studies in mice showed that, in contrast to intravenous injection, IT was undetectable by enzyme-linked immunosorbent assay in blood following i.duc injection of up to 3.0 µg HB21(Fv)-PE40. We demonstrated the antitumor efficacy of HB21(Fv)-PE40 in two mammary-in-duct (MIND) models, MCF7 and SUM225, grown in NOD/SCID/gamma mice. Tumors were undetectable by In Vivo Imaging System (IVIS) imaging in intraductally treated mice within 1 wk of initiation of the regimen (IT once weekly/3 wk, 1.5 µg/teat). MCF7 tumor-bearing mice remained tumor free for up to 60 d of observation with i.duc IT, whereas the HB21 antibody alone or intraperitoneal IT treatment had minimal/no antitumor effects. These and similar findings in the SUM225 MIND model were substantiated by analysis of mammary gland whole mounts, histology, and immunohistochemistry for the proteins Ki67, CD31, CD71 (TFR), and Ku80. This study provides a strong preclinical foundation for conducting feasibility and safety trials in patients with stage 0 breast cancer.


Assuntos
ADP Ribose Transferases , Toxinas Bacterianas , Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Exotoxinas , Imunotoxinas , Terapia de Alvo Molecular , Receptores da Transferrina , Fatores de Virulência , ADP Ribose Transferases/administração & dosagem , ADP Ribose Transferases/metabolismo , Animais , Anticorpos Monoclonais/administração & dosagem , Toxinas Bacterianas/administração & dosagem , Neoplasias da Mama/terapia , Carcinoma Intraductal não Infiltrante/terapia , Exotoxinas/administração & dosagem , Feminino , Humanos , Imunotoxinas/administração & dosagem , Células MCF-7 , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Receptores da Transferrina/metabolismo , Fatores de Virulência/administração & dosagem , Exotoxina A de Pseudomonas aeruginosa
3.
Plant J ; 116(3): 921-941, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37609706

RESUMO

Schrenkiella parvula, a leading extremophyte model in Brassicaceae, can grow and complete its lifecycle under multiple environmental stresses, including high salinity. Yet, the key physiological and structural traits underlying its stress-adapted lifestyle are unknown along with trade-offs when surviving salt stress at the expense of growth and reproduction. We aimed to identify the influential adaptive trait responses that lead to stress-resilient and uncompromised growth across developmental stages when treated with salt at levels known to inhibit growth in Arabidopsis and most crops. Its resilient growth was promoted by traits that synergistically allowed primary root growth in seedlings, the expansion of xylem vessels across the root-shoot continuum, and a high capacity to maintain tissue water levels by developing thicker succulent leaves while enabling photosynthesis during salt stress. A successful transition from vegetative to reproductive phase was initiated by salt-induced early flowering, resulting in viable seeds. Self-fertilization in salt-induced early flowering was dependent upon filament elongation in flowers otherwise aborted in the absence of salt during comparable plant ages. The maintenance of leaf water status promoting growth, and early flowering to ensure reproductive success in a changing environment, were among the most influential traits that contributed to the extremophytic lifestyle of S. parvula.


Assuntos
Arabidopsis , Brassicaceae , Brassicaceae/fisiologia , Arabidopsis/fisiologia , Flores , Estresse Salino , Estresse Fisiológico , Água
4.
Int J Cancer ; 155(4): 766-775, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38594805

RESUMO

The inconsistency between mismatch repair (MMR) protein immunohistochemistry (IHC) and microsatellite instability PCR (MSI-PCR) methods has been widely reported. We aim to investigate the prognosis and the effect of immunotherapy in dMMR by IHC but MSS by MSI-PCR (dMMR&MSS) colorectal cancer (CRC) patients. A microsatellite instability (MSI) predicting model was established to help find dMMR&MSS patients. MMR and MSI states were detected by the IHC and MSI-PCR in 1622 CRC patients (ZS6Y-1 cohort). Logistic regression analysis was used to screen clinical features to construct an MSI-predicting nomogram. We propose a new nomogram-based assay to find patients with dMMR&MSS, in which the MSI-PCR assay only detects dMMR patients with MSS predictive results. We applied the new strategy to a random cohort of 248 CRC patients (ZS6Y-2 cohort). The consistency of MMR IHC and MSI-PCR in the ZS6Y-1 cohort was 95.7% (1553/1622). Both pMMR&MSS and dMMR&MSS groups experienced significantly shorter overall survival (OS) than those in dMMR by IHC and MSI-H by MSI-PCR (dMMR&MSI-H) group (hazard ratio [HR] = 2.429, 95% confidence interval [CI]: 1.89-3.116, p < .01; HR = 21.96, 95% CI: 7.24-66.61, p < .01). The dMMR&MSS group experienced shorter OS than the pMMR&MSS group, but the difference did not reach significance (log rank test, p = .0686). In the immunotherapy group, the progression-free survival of dMMR&MSS patients was significantly shorter than that of dMMR&MSI-H patients (HR = 13.83, 95% CI: 1.508-126.8, p < .05). The ZS6Y-MSI-Pre nomogram (C-index = 0.816, 95% CI: 0.792-0.841, already online) found 66% (2/3) dMMR&MSS patients in the ZS6Y-2 cohort. There are significant differences in OS and immunotherapy effect between dMMR&MSI-H and dMMR&MSS patients. Our prediction model provides an economical way to screen dMMR&MSS patients.


Assuntos
Neoplasias Colorretais , Reparo de Erro de Pareamento de DNA , Imunoterapia , Instabilidade de Microssatélites , Nomogramas , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/terapia , Neoplasias Colorretais/imunologia , Feminino , Masculino , Prognóstico , Pessoa de Meia-Idade , Reparo de Erro de Pareamento de DNA/genética , Imunoterapia/métodos , Idoso , Imuno-Histoquímica , Adulto , Biomarcadores Tumorais/genética
5.
PLoS Pathog ; 18(7): e1010660, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35816513

RESUMO

Coxiella burnetii is the etiological agent of the zoonotic disease Q fever, which is featured by its ability to replicate in acid vacuoles resembling the lysosomal network. One key virulence determinant of C. burnetii is the Dot/Icm system that transfers more than 150 effector proteins into host cells. These effectors function to construct the lysosome-like compartment permissive for bacterial replication, but the functions of most of these effectors remain elusive. In this study, we used an affinity tag purification mass spectrometry (AP-MS) approach to generate a C. burnetii-human protein-protein interaction (PPI) map involving 53 C. burnetii effectors and 3480 host proteins. This PPI map revealed that the C. burnetii effector CBU0425 (designated CirB) interacts with most subunits of the 20S core proteasome. We found that ectopically expressed CirB inhibits hydrolytic activity of the proteasome. In addition, overexpression of CirB in C. burnetii caused dramatic inhibition of proteasome activity in host cells, while knocking down CirB expression alleviated such inhibitory effects. Moreover, we showed that a region of CirB that spans residues 91-120 binds to the proteasome subunit PSMB5 (beta 5). Finally, PSMB5 knockdown promotes C. burnetii virulence, highlighting the importance of proteasome activity modulation during the course of C. burnetii infection.


Assuntos
Coxiella burnetii , Febre Q , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Mapas de Interação de Proteínas , Febre Q/metabolismo , Vacúolos/metabolismo
6.
Langenbecks Arch Surg ; 409(1): 146, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38691172

RESUMO

OBJECTIVE: In this paper, a single-hand-operated hepatic pedicle clamp was introduced, and its application value in laparoscopic liver tumor resection was preliminarily discussed. METHODS: The clinical data of 67 patients who underwent laparoscopic liver tumor resection at the First Affiliated Hospital of Wannan Medical College from March 2019 to October 2023 were retrospectively analyzed. The Pringle maneuver was performed with a hepatic pedicle clamp during the operation. The preoperative, intraoperative and postoperative clinical data were observed and recorded. RESULTS: Sixty-seven patients had a median block number, block time, intraoperative blood loss, and postoperative length of hospital stay of 4, 55 min, 400 ml, and 7 days, respectively. The average operation time was 304.9±118.4 min, the time required for each block was 3.2±2.4 s, and the time required for each removed block was 2.6±0.7 s. None of the patients developed portal vein thrombosis or hepatic artery aneurysm formation. CONCLUSION: The hepatic pedicle clamping clamp is simple to use in laparoscopic hepatectomy, optimizes the operation process, and has a reliable blocking effect. It is recommended for clinical application.


Assuntos
Hepatectomia , Laparoscopia , Neoplasias Hepáticas , Humanos , Hepatectomia/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Hepáticas/cirurgia , Laparoscopia/métodos , Idoso , Constrição , Adulto , Duração da Cirurgia , Tempo de Internação , Perda Sanguínea Cirúrgica/prevenção & controle , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Resultado do Tratamento
7.
BMC Geriatr ; 24(1): 495, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38840071

RESUMO

BACKGROUND: Social alienation refers to the state of feeling isolated, helpless, and unsatisfied due to maintaining distance from others or avoiding social interaction and activities. This phenomenon is caused by a lack of social skills, social anxiety, physical health problems, and other reasons. Older maintenance hemodialysis patients are exposed to a higher risk of social alienation. However, previous studies have been performed using the total score of the scale, which does not allow the identification of the characteristics of various patient groups with different levels of social alienation. In contrast, latent profile analysis can classify individuals into different categories based on continuous observational indicators, which improves accuracy and provides a more objective assessment by accounting for the uncertainty of variables. Given the concealed nature of social alienation and the differences in characteristics and treatment measures between different profiles, developing a predictive model for social alienation in older maintenance hemodialysis patients holds significance. OBJECTIVE: To explore the latent profile analysis of social alienation in older maintenance hemodialysis patients and to develop and validate a predictive model for social alienation in this population. METHODS: A total of 350 older maintenance hemodialysis patients were selected as the study subjects using convenience sampling. A cross-sectional survey was conducted using a general information questionnaire, the Generalized Alienation Scale, and the Self-Perceived Burden Scale. Based on the results of the Generalized Alienation Scale, a latent profile analysis was performed, followed by univariate analysis and multinomial logistic regression to develop a predictive model. The effectiveness of the predictive model was evaluated in terms of its authenticity, reliability, and predictive ability. RESULTS: Three hundred nineteen valid questionnaires were collected. The social alienation of older maintenance hemodialysis patients based on latent profile analysis were divided into three profiles, which were named the low/medium/high-symptom groups, comprising 21%, 38.9%, and 40.1% of participants, respectively. Based on male, monthly social activity hours, Age-Adjusted Charlson Comorbidity Index, dialysis age, and Self-Perceived Burden Scale, a predictive model of social alienation for older maintenance hemodialysis patients was developed, and the Hosmer-Lemeshow tests showed no statistical significance (P > 0.05). The model has high predictive efficiency in authenticity, reliability and predictability. CONCLUSION: Older maintenance hemodialysis patients exhibited moderate to high levels of social alienation. The latent profile analysis based method was used to divide patients into low/medium/high-symptom profiles, and the predictive model demonstrates excellent authenticity, reliability, and predictability.


Assuntos
Diálise Renal , Alienação Social , Humanos , Masculino , Estudos Transversais , Feminino , Diálise Renal/psicologia , Idoso , Alienação Social/psicologia , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade
8.
Angew Chem Int Ed Engl ; : e202406738, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869842

RESUMO

Supramolecular mechanophores typically exhibit much lower mechanical strengths than covalent counterparts, with strengths usually around 100 pN, which is significantly lower than the nN-scale strength of covalent bonds. Inspired by the slow dissociation kinetics of the cucurbit[7]uril (CB[7])-hexanoate-isoquinoline (HIQ) complex, we discovered that charge-dipole repulsion can be utilized to create strong supramolecular mechanophores. When activated at its -COO- state, the CB[7]-HIQ complex exhibits a high mechanical strength of ~700 pN, comparable to weak covalent bonds such as Au-S bonds or a thiol-maleimide adducts. The strength of the CB[7]-HIQ complex can also be tuned with pH in a gradual manner, with a minimum value of ~150 pN at its -COOH state, similar to an ordinary supramolecular conjugate. This research may pave the way for the development of supramolecular architectures that combine the advantages of covalent and supramolecular systems.

9.
Int J Cancer ; 153(5): 1067-1079, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37255230

RESUMO

Given that the transition from ductal carcinoma in situ (DCIS) to invasive breast cancer (BC) is crucial during the BC progression, the mechanism involved in the invasion transition behind triple-negative breast cancer (TNBC) and estrogen receptor-positive (ER-positive) subtype has remained elusive. This article detected distinct invasion patterns of BC cells between the ER-positive and TNBC using intraductal murine models with intraductal administration of carbon nanoparticles (CNPs). First, the feasibility of the utility of CNPs as a tracer was proved. The area ratio of CNPs and tumor cells invading the stroma at the late stage was found significantly higher than that in the early stage in MNU-induced ER-positive BC. However, opposite results were obtained in the triple-negative model. Consequently, we proposed that the ER-positive phenotype cells behave differently between different stages during tumor progression while there is no such difference in the invasion process of TNBC cells. The analysis regarding the duct integrity along with immunohistochemical characteristics further explained the distinct invasion features between the ER-positive and triple-negative subtypes. Last, the relationship between the duct thickness and the duct integrity suggested that ER-positive tumors gradually increased in size within the lumen before the invasion. Overall, this study suggested the different invasion characteristics of ER-positive BC and TNBC in vivo.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Feminino , Receptores de Estrogênio , Receptor ErbB-2/análise , Carcinoma Intraductal não Infiltrante/patologia , Carbono , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Biomarcadores Tumorais
10.
J Transl Med ; 21(1): 145, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36829227

RESUMO

BACKGROUND: The realization of the "microbiota-gut-brain" axis plays a critical role in neuropsychiatric disorders, particularly depression, is advancing rapidly. Matrine is a natural bioactive compound, which has been found to possess potential antidepressant effect. However, the underlying mechanisms of regulation of the "microbiota-gut-brain" axis in the treatment of depression by oral matrine remain elusive. METHODS: Its antidepressant effects were initially evaluated by behavioral tests and relative levels of monoamine neurotransmitters, and matrine has been observed to attenuate the depression-like behavior and increase neurotransmitter content in CUMS-induced mice. Subsequently, studies from the "gut" to "brain" were conducted, including detection of the composition of gut microbiota by 16S rRNA sequencing; the metabolomics detection of gut metabolites and the analysis of differential metabolic pathways; the assessment of relative levels of diamine oxidase, lipopolysaccharide, pro-inflammatory cytokines, and brain-derived neurotrophic factor (BDNF) by ELISA kits or immunofluorescence. RESULTS: Matrine could regulate the disturbance of gut microbiota and metabolites, restore intestinal permeability, and reduce intestinal inflammation, thereby reducing the levels of pro-inflammatory cytokines in peripheral blood circulation and brain regions, and ultimately increase the levels of BDNF in brain. CONCLUSION: Matrine may ameliorate CUMS-induced depression in mice by modulating the "microbiota-gut-brain" axis.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Depressão , Camundongos , Animais , Depressão/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Matrinas , Eixo Encéfalo-Intestino , RNA Ribossômico 16S , Antidepressivos/farmacologia , Citocinas/metabolismo , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia
11.
BMC Cancer ; 23(1): 675, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464346

RESUMO

BACKGROUND: Current guidelines only propose the importance of perineural invasion(PNI) on prognosis in stage II colon cancer. However, the prognostic value of PNI in other stages of colorectal cancer (CRC) is ambiguous. METHODS: This single-center retrospective cohort study included 3485 CRC patients who underwent primary colorectal resection between January 2013 and December 2016 at the Sixth Affiliated Hospital of Sun Yat-sen University. Associations of PNI with overall survival (OS) and disease-free survival (DFS) were evaluated using multivariable Cox proportional hazards regression models. In addition, interaction analyses were performed to explore the prognostic effects of PNI in different clinical subgroups. RESULTS: After median follow-up of 61.9 months, we found PNI was associated with poorer OS (adjusted hazard ratio [aHR], 1.290; 95% CI, 1.087-1.531) and DFS (aHR, 1.397; 95% CI, 1.207-1.617), irrespective of tumor stage. Interestingly, the weight of PNI was found second only to incomplete resection in the nomogram for risk factors of OS and DFS in stage II CRC patients. Moreover, OS and DFS were insignificantly different between stage II patients with PNI and stage III patients (both P > 0.05). PNI was found to be an independent prognostic factor of DFS in stage III CRC (aHR: 1.514; 95% CI, 1.211-1.892) as well. Finally, the adverse effect of PNI on OS was more significant in female, early-onset, and diabetes-negative patients than in their counterparts (interaction P = 0.0213, 0.0280, and 0.0186, respectively). CONCLUSION: PNI was an important prognostic factor in CRC, more than in stage II. The survival of patients with stage II combined with perineural invasion is similar with those with stage III. PNI in stage III CRC also suggests a worse survival.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Humanos , Feminino , Prognóstico , Estudos Retrospectivos , Neoplasias Colorretais/cirurgia , Intervalo Livre de Doença , Estadiamento de Neoplasias , Invasividade Neoplásica
12.
Mikrochim Acta ; 190(11): 444, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37851103

RESUMO

A multi-signal aptasensor for thrombin determination is proposed based on catalytically active gold nanoparticles (AuNPs) and fluorescent silicon quantum dots (SiQDs). Yellow 4-Nitrophenol (4-NP) could be converted to colorless 4-Aminophenol (4-AP) by catalytically active aptamer-modified AuNPs (S1-AuNPs). The SiQDs emitted strong blue fluorescence at 455 nm at the excitation wavelength of 367 nm. When thrombin was absent, S1-AuNPs could catalytically reduce yellow 4-NP to colorless 4-AP. When thrombin was added, the aptamer could be transformed into a G-quadruplex structure, which masked the surface-active catalytic sites of AuNPs and restrained the reduction of 4-NP. Thus, the fluorescence of SiQDs was greatly quenched by 4-NP through the inner filter effect (IFE), and the solution color remained yellow. As the concentration of thrombin increased, the catalytic activity of S1-AuNPs decreased. The concentration of 4-NP that was converted to 4-AP declined and the unconverted 4-NP increased. In this process, the absorption peak of 4-NP at 400 nm increased while the fluorescence emission of SiQDs at 455 nm decreased. The linear ranges of the fluorometric and colorimetric aptasensor were 0.5-30 nM and 0.3-30 nM, respectively. The limits of detection (LOD) for the two modes were 0.15 nM and 0.13 nM. Furthermore, a portable sensing platform was constructed by combining the smartphone-based device with the software ImageJ for the determination of thrombin. With the advantages of cost-effectiveness, simplicity of operation and broad applicability, this aptasensor provided a new perspective for on-site determination of thrombin in the clinical field.


Assuntos
Aptâmeros de Nucleotídeos , Nanopartículas Metálicas , Pontos Quânticos , Pontos Quânticos/química , Ouro/química , Trombina , Silício , Nanopartículas Metálicas/química , Aptâmeros de Nucleotídeos/química , Corantes
13.
Angew Chem Int Ed Engl ; 62(14): e202218491, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36759322

RESUMO

Materials with tunable emission colors has attracted increasing interest in both fundamental research and applications. As a key member of light-emitting materials family, lanthanide doped upconversion nanoparticles (UCNPs) have been intensively demonstrated to emit light in any color upon near-infrared excitation. However, realizing the trichromatic emission in UCNPs with a fixed composition remains a great challenge. Here, without excitation pulsed modulation and three different near-infrared pumping, we report an experimental design to fine-control emission in the full color gamut from core-shell-structured UCNPs by manipulating the energy migration through dual-channel pump scheme. We also demonstrate their potential application in full-color display. These findings may benefit the future development of convenient and versatile optical methos for multicolor tuning and open up the possibility of constructing full-color volumetric display systems with high spatiotemporal resolution.

14.
J Am Chem Soc ; 144(15): 6992-7000, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35404602

RESUMO

Modifying surfaces using free radical polymerization (FRP) offers a means to incorporate the diverse physicochemical properties of vinyl polymers onto new materials. Here, we harness the universal surface attachment of polydopamine (PDA) to "prime" a range of different surfaces for free radical polymer attachment, including glass, cotton, paper, sponge, and stainless steel. We show that the intrinsic free radical species present in PDA can serve as an anchor point for subsequent attachment of propagating vinyl polymer macroradicals through radical-radical coupling. Leveraging a straightforward, twofold soak-wash protocol, FRP over the PDA-functionalized surfaces results in covalent polymer attachment on both porous and nonporous substrates, imparting new properties to the functionalized materials, including enhanced hydrophobicity, fluorescence, or temperature responsiveness. Our strategy is then extended to covalently incorporate PDA nanoparticles into organo-/hydrogels via radical cross-linking, yielding tunable PDA-polymer composite networks. The propensity of PDA free radicals to quench FRP is studied using in situ 1H nuclear magnetic resonance and electron paramagnetic resonance spectroscopy, revealing a surface area-dependent macroradical scavenging mechanism that underpins PDA-polymer conjugation. By combining the arbitrary surface attachment of PDA with the broad physicochemical properties of vinyl polymers, our strategy provides a straightforward route for imparting unlimited new functionality to practically any surface.


Assuntos
Indóis , Polímeros , Radicais Livres , Indóis/química , Polimerização , Polímeros/química
15.
Cancer Sci ; 113(7): 2288-2296, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35293080

RESUMO

Our previous study identified annexin A2 (ANXA2) as a Gaq-interacting partner in natural killer/T cell lymphoma (NKTCL) cells transfected with the GNAQ T96S mutation vector by immunoprecipitation and mass spectrometry; however, the detailed molecular mechanisms by which GNAQ T96S might regulate ANXA2 remain to be defined in NKTCL. Herein, we found that the GNAQ T96S mutation significantly promotes the phosphorylation of ANXA2 at the Y24 site, whereas phosphorylation of ANXA2 abolishes the ability of WT GNAQ to trigger cell apoptosis. Further investigation revealed that a GNAQ T96S peptide inhibitor induced apoptosis by competing with ANXA2 binding to GNAQ T96S in NKTCL cells. In vivo animal experiments showed that a GNAQ T96S peptide inhibitor suppresses the growth of NKTCL cells carrying the GNAQ T96S mutation. Our current data suggest a role for GNAQ T96S/Src/ANXA2 in mediating the apoptosis of NKTCL cells, and the GNAQ T96S peptide could be a promising agent for therapy in NKTCL patients.


Assuntos
Anexina A2 , Linfoma de Células T , Linfoma , Animais , Anexina A2/genética , Anexina A2/metabolismo , Apoptose/genética , Células Matadoras Naturais/metabolismo , Linfoma de Células T/genética , Mutação
16.
New Phytol ; 236(3): 1006-1026, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35909295

RESUMO

Plant adaptation to a desert environment and its endemic heat stress is poorly understood at the molecular level. The naturally heat-tolerant Brassicaceae species Anastatica hierochuntica is an ideal extremophyte model to identify genetic adaptations that have evolved to allow plants to tolerate heat stress and thrive in deserts. We generated an A. hierochuntica reference transcriptome and identified extremophyte adaptations by comparing Arabidopsis thaliana and A. hierochuntica transcriptome responses to heat, and detecting positively selected genes in A. hierochuntica. The two species exhibit similar transcriptome adjustment in response to heat and the A. hierochuntica transcriptome does not exist in a constitutive heat 'stress-ready' state. Furthermore, the A. hierochuntica global transcriptome as well as heat-responsive orthologs, display a lower basal and higher heat-induced expression than in A. thaliana. Genes positively selected in multiple extremophytes are associated with stomatal opening, nutrient acquisition, and UV-B induced DNA repair while those unique to A. hierochuntica are consistent with its photoperiod-insensitive, early-flowering phenotype. We suggest that evolution of a flexible transcriptome confers the ability to quickly react to extreme diurnal temperature fluctuations characteristic of a desert environment while positive selection of genes involved in stress tolerance and early flowering could facilitate an opportunistic desert lifestyle.


Assuntos
Arabidopsis , Brassicaceae , Aclimatação , Adaptação Fisiológica/genética , Arabidopsis/genética , Brassicaceae/genética , Regulação da Expressão Gênica de Plantas , Transcriptoma/genética
17.
Cancer Cell Int ; 22(1): 36, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35073926

RESUMO

BACKGROUND: To determine whether concurrent chemotherapy is necessary during locoregional radiotherapy (RT) after palliative chemotherapy (PCT) in patients with de novo metastatic nasopharyngeal carcinoma (mNPC). METHODS: A total of 746 patients with mNPC from 2000 to 2017 at our hospital were retrospectively reviewed. Among them, 355 patients received PCT followed by RT. Overall survival (OS) and progression-free survival (PFS), including locoregional progression-free survival (LRPFS) and distant progression-free survival (DPFS) were estimated with the Kaplan-Meier method and log-rank test. Cox proportional-hazards models, landmark analyses, propensity score matching, and subgroup analyses were used to address confounding. RESULTS: Of the patients included in our study, 192 received radiotherapy alone after PCT (PCT + RT), and 163 received concurrent chemoradiotherapy after PCT (PCT + CCRT). The prognosis of PCT + CCRT was significantly better than that of PCT + RT (5 year OS, 53.0 vs 36.2%; P = 0.004). After matching, the 5 year OS rates of the two groups were 55.7 and 39.0%, respectively (P = 0.034) and the median DPFS were 29.4 and 18.7 months, respectively (P = 0.052). Multivariate Cox regression analysis indicated that PCT + CCRT was an independent favorable prognostic factor (P = 0.009). In addition, conducting concurrent chemoradiotherapy after 4-6 cycles of PCT or conducting concurrent chemotherapy with single-agent platinum was associated with significant survival benefit in the matched cohort (5 year OS rate, 60.4 or 57.4%, respectively). The survival difference between groups remained significant when evaluating patients who survived for ≥ 1 year (P = 0.028). CONCLUSIONS: The optimal treatment strategy of mNPC is the combination of PCT followed by concurrent chemoradiotherapy. More specifically, concurrent chemoradiotherapy with single-agent platinum after 4-6 cycles of PCT is suggested.

18.
Biomacromolecules ; 23(6): 2572-2585, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35584062

RESUMO

The estrone ligand is used for modifying nanoparticle surfaces to improve their targeting effect on cancer cell lines. However, to date, there is no common agreement on the ideal linker length to be used for the optimum targeting performance. In this study, we aimed to investigate the impact of poly(poly ethylene glycol methyl ether methacrylate) (PPEGMEMA) linker length on the cellular uptake behavior of polymer-coated upconverting nanoparticles (UCNPs). Different triblock terpolymers, poly(poly (ethylene glycol) methyl ether methacrylate)-block-polymethacrylic acid-block-polyethylene glycol methacrylate phosphate (PPEGMEMAx-b-PMAAy-b-PEGMP3: x = 7, 15, 33, and 80; y = 16, 20, 18, and 18), were synthesized with different polymer linker chain lengths between the surface and the targeting ligand by reversible addition-fragmentation chain transfer polymerization. The estrone ligand was attached to the polymer via specific terminal conjugation. The cellular association of polymer-coated UCNPs with linker chain lengths was evaluated in MCF-7 cells by flow cytometry. Our results showed that the bioactivity of ligand modification is dependent on the length of the polymer linker. The shortest polymer PPEGMEMA7-b-PMAA16-b-PEGMP3 with estrone at the end of the polymer chain was found to have the best cellular association behavior in the estrogen receptor (ER)α-positive expression cell line MCF-7. Additionally, the anticancer drug doxorubicin•HCl was encapsulated in the nanocarrier to evaluate the 2D and 3D cytotoxicity. The results showed that estrone modification could efficiently improve the cellular uptake in ERα-positive expression cell lines and in 3D spheroid models.


Assuntos
Éteres Metílicos , Nanopartículas , Estrona/farmacologia , Humanos , Ligantes , Metacrilatos , Polietilenoglicóis , Polímeros/farmacologia
19.
Analyst ; 147(4): 677-684, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35083988

RESUMO

In this work, we report a novel and ultrasensitive dual-signal fluorescence emission detection system for protamine and trypsin based on the electrostatic interaction between polyethyleneimine (PEI) surface-modified positively charged carbon quantum dots (CDs-PEI) and the anionic fluorescent dye Eosin Y. The fluorescence system exhibited yellow-green fluorescence from Eosin Y and blue fluorescence from CDs-PEI. As a cationic peptide, protamine quenched the yellow-green fluorescence of Eosin Y at 542 nm through electrostatic interaction. In the presence of trypsin, protamine was specifically hydrolyzed by trypsin, which led to the subsequent recovery of the fluorescence of Eosin Y. Simultaneously, the blue fluorescence emission of CDs-PEI at 452 nm remained constant during the whole process. Hence, a ratiometric fluorescent nanoprobe for protamine and trypsin detection with high sensitivity was successfully constructed based on CDs-PEI and Eosin Y. For protamine detection, the ratiometric fluorescence intensity (I542/I452) exhibited an excellent linear relationship in the range of 0.1-5.2 µg mL-1 with a limit of detection (LOD) of 0.03 µg mL-1. And the linear relationship between I542/I452 and trypsin concentration ranged from 0.4 to 56 ng mL-1 with an LOD of 0.21 ng mL-1. Upon evaluating the performance of this method for the detection of trypsin in actual human urine samples, satisfactory results were finally obtained.


Assuntos
Polietilenoimina , Pontos Quânticos , Carbono , Amarelo de Eosina-(YS) , Corantes Fluorescentes , Humanos , Limite de Detecção , Protaminas , Espectrometria de Fluorescência , Tripsina
20.
Mikrochim Acta ; 189(4): 135, 2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35257215

RESUMO

Iron-cobalt oxide nanosheets (FeCo-ONSs) were proved to have intrinsic peroxidase-like activity. Additionally, the peroxidase-like activity of FeCo-ONSs toward the oxidation of 3,3,5,5-tetramethylbenzidine (TMB) was dramatically enhanced after heparin addition due to the stronger affinity toward TMB. Protamine combines with heparin, so the promotion of peroxidase-like activity of FeCo-ONSs with heparin was suppressed. With the addition of trypsin, protamine was hydrolyzed and the enhancement effect of catalytic activity of FeCo-ONSs was recovered. Based on above process, a sensitive colorimetric platform for trypsin activity determination was constructed through measuring the absorbance of produced oxTMB at 652 nm, providing a linear detection range of 5 to 500 ng/mL and a low detection limit of 2.8 ng/mL. The method was applied to trypsin determination in real samples (human urine sample and multienzyme tablet sample) with satisfactory results, illustrating the potential application of this biosensor.


Assuntos
Colorimetria , Peroxidase , Cobalto , Colorimetria/métodos , Heparina , Humanos , Ferro , Óxidos , Oxirredutases , Peroxidases , Protaminas , Tripsina
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