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1.
Plant Cell ; 34(10): 3718-3736, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-35861414

RESUMO

Pollen tube guidance regulates the growth direction and ovule targeting of pollen tubes in pistils, which is crucial for the completion of sexual reproduction in flowering plants. The Arabidopsis (Arabidopsis thaliana) pollen-specific receptor kinase (PRK) family members PRK3 and PRK6 are specifically tip-localized and essential for pollen tube growth and guidance. However, the mechanisms controlling the polar localization of PRKs at the pollen tube tip are unclear. The Arabidopsis P4-ATPase ALA3 helps establish the polar localization of apical phosphatidylserine (PS) in pollen tubes. Here, we discovered that loss of ALA3 function caused pollen tube defects in growth and ovule targeting and significantly affected the polar localization pattern of PRK3 and PRK6. Both PRK3 and PRK6 contain two polybasic clusters in the intracellular juxtamembrane domain, and they bound to PS in vitro. PRK3 and PRK6 with polybasic cluster mutations showed reduced or abolished binding to PS and altered polar localization patterns, and they failed to effectively complement the pollen tube-related phenotypes of prk mutants. These results suggest that ALA3 influences the precise localization of PRK3, PRK6, and other PRKs by regulating the distribution of PS, which plays a key role in regulating pollen tube growth and guidance.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Adenosina Trifosfatases/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Fosfatidilserinas/metabolismo , Fosfolipídeos/metabolismo , Tubo Polínico , Proteínas Serina-Treonina Quinases
2.
Proc Natl Acad Sci U S A ; 119(46): e2210562119, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36343224

RESUMO

The development of chimeric antigen receptor (CAR) T cell therapy has become a critical milestone in modern oncotherapy. Despite the remarkable in vitro effectiveness, the problem of safety and efficacy of CAR T cell therapy against solid tumors is challenged by the lack of tumor-specific antigens required to avoid on-target off-tumor effects. Spatially separating the cytotoxic function of CAR T cells from tumor antigen recognition provided by protein mediators allows for the precise control of CAR T cell cytotoxicity. Here, the high affinity and capability of the bacterial toxin-antitoxin barnase-barstar system were adopted to guide CAR T cells to solid tumors. The complementary modules based on (1) ankyrin repeat (DARPin)-barnase proteins and (2) barstar-based CAR (BsCAR) were designed to provide switchable targeting to tumor cells. The alteration of the DARPin-barnase switches enabled the targeting of different tumor antigens with a single BsCAR. A gradual increase in cytokine release and tunable BsCAR T cell cytotoxicity was achieved by varying DARPin-barnase loads. Switchable BsCAR T cell therapy was able to eradicate the HER2+ ductal carcinoma in vivo. Guiding BsCAR T cells by DARPin-barnase switches provides a universal approach for a controlled multitargeted adoptive immunotherapy.


Assuntos
Neoplasias , Linfócitos T , Humanos , Receptores de Antígenos de Linfócitos T , Imunoterapia Adotiva , Neoplasias/metabolismo , Antígenos de Neoplasias
3.
Biochem Biophys Res Commun ; 718: 149931, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38723415

RESUMO

Oncolytic viruses (OVs) have shown potential in converting a "cold" tumor into a "hot" one and exhibit effectiveness in various cancer types. However, only a subset of patients respond to oncolytic virotherapy. It is important to understand the resistance mechanisms to OV treatment in pancreatic ductal adenocarcinoma (PDAC) to engineer oncolytic viruses. In this study, we used transcriptome RNA sequencing (RNA-seq) to identify Visfatin, which was highly expressed in the responsive tumors following OV treatment. To explore the antitumor efficacy, we modified OV-mVisfatin, which effectively inhibited tumor growth. For the first time, we revealed that Visfatin promoted the antitumor efficacy of OV by remodeling the tumor microenvironment, which involved enhancing CD8+ T cell and DC cell infiltration and activation, repolarizing macrophages towards the M1-like phenotype, and decreasing Treg cells using single-cell RNA sequencing (scRNA-seq) and flow cytometry. Furthermore, PD-1 blockade significantly enhanced OV-mVisfatin antitumor efficacy, offering a promising new therapeutic strategy for PDAC.


Assuntos
Herpesvirus Humano 1 , Nicotinamida Fosforribosiltransferase , Terapia Viral Oncolítica , Vírus Oncolíticos , Neoplasias Pancreáticas , Microambiente Tumoral , Animais , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Camundongos , Terapia Viral Oncolítica/métodos , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Herpesvirus Humano 1/genética , Linhagem Celular Tumoral , Vírus Oncolíticos/genética , Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/imunologia , Camundongos Endogâmicos C57BL , Humanos , Linfócitos T CD8-Positivos/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Feminino
4.
Biochem Biophys Res Commun ; 698: 149546, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38266314

RESUMO

The low clinical response rate of checkpoint blockades, such as PD-1 and CTLA-4, highlighted the requirements of agonistic antibodies to boost optimal T cell responses. OX40, a co-stimulatory receptor on the T cells, plays a crucial role in promoting T cell survival and differentiation. However, the clinical efficacy of anti-OX40 agonistic antibodies was unimpressive. To explore the mechanism underlying the action of anti-OX40 agonists to improve the anti-tumor efficacy, we analyzed the dynamic changes of tumor-infiltrating immune cells at different days post-treatments using single-cell RNA-sequencing (scRNA-seq). In this study, we found that tumor-infiltrating regulatory T (Treg) cells were reduced after two rounds of anti-OX40 treatment, but the increase of infiltration and activation of CD8+ effector T cells, as well as M1 polarization in the tumor were only observed after three rounds of treatments. Moreover, our group first analyzed the antitumor effect of anti-OX40 treatments on regulating the macrophages and discovered the dynamic changes of vascular endothelial growth factor (VEGF) and CD40 signaling pathways on macrophages, indicating their possibility to being potential combination targets to improve the anti-OX40 agonists efficacy. The combination of VEGFR inhibitors or anti-CD40 agonist antibody with anti-OX40 agonists exhibited more remarkable inhibition of tumor growth. Therefore, the mechanism-driven combination of anti-OX40 agonists with VEGFR inhibitors or anti-CD40 agonists represented promising strategies.


Assuntos
Linfócitos T Reguladores , Fator A de Crescimento do Endotélio Vascular , Anticorpos , Imunoterapia , Macrófagos
5.
Cardiovasc Diabetol ; 23(1): 267, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039597

RESUMO

BACKGROUND: Sodium-Glucose Cotransporter-2 Inhibitor (SGLT2i) is a novel oral drug for treating type 2 diabetes mellitus (T2DM) with demonstrated cardiovascular benefits. Previous studies in apolipoprotein E knockout mice have shown that SGLT2i is associated with attenuated progression of atherosclerosis. However, whether this effect extends to T2DM patients with coronary atherosclerosis in real-world settings remains unknown. METHODS: In this longitudinal cohort study using coronary computed tomography angiography (CCTA), T2DM patients who underwent ≥ 2 CCTA examinations at our center between 2019 and 2022 were screened. Eligible patients had multiple study plaques, defined as non-obstructive stenosis at baseline and not intervened during serial CCTAs. Exclusion criteria included a CCTA time interval < 12 months, prior SGLT2i treatment, or initiation/discontinuation of SGLT2i during serial CCTAs. Plaque volume (PV) and percent atheroma volume (PAV) were measured for each study plaque using CCTA plaque analysis software. Patients and plaques were categorized based on SGLT2i therapy and compared using a 1:1 propensity score matching (PSM) analysis. RESULTS: The study included 236 patients (mean age 60.5 ± 9.5 years; 69.1% male) with 435 study plaques (diameter stenosis ≥ 50%, 31.7%). Following SGLT2i treatment for a median duration of 14.6 (interquartile range: 13.0, 20.0) months, overall, non-calcified, and low-attenuation PV and PAV were significantly decreased, while calcified PV and PAV were increased (all p < 0.001). Meanwhile, reductions in overall PV, non-calcified PV, overall PAV, and non-calcified PAV were significantly greater in SGLT2i-treated compared to non-SGLT2i-treated plaques (all p < 0.001). PSM analysis showed that SGLT2i treatment was associated with higher reductions in overall PV (- 11.77 mm3 vs. 4.33 mm3, p = 0.005), non-calcified PV (- 16.96 mm3 vs. - 1.81 mm3, p = 0.017), overall PAV (- 2.83% vs. 3.36%, p < 0.001), and non-calcified PAV (- 4.60% vs. 0.70%, p = 0.003). These findings remained consistent when assessing annual changes in overall and compositional PV and PAV. Multivariate regression models demonstrated that SGLT2i therapy was associated with attenuated progression of overall or non-calcified PV or PAV, even after adjusting for cardiovascular risk factors, medications, and baseline overall or non-calcified PV or PAV, respectively (all p < 0.05). The effect of SGLT2i on attenuating non-calcified plaque progression was consistent across subgroups (all p for interaction > 0.05). CONCLUSIONS: In this longitudinal CCTA cohort of T2DM patients, SGLT2i therapy markedly regressed coronary overall PV and PAV, mainly result from a significant reduction in non-calcified plaque.


Assuntos
Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Placa Aterosclerótica , Valor Preditivo dos Testes , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Masculino , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Feminino , Pessoa de Meia-Idade , Estudos Longitudinais , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/diagnóstico , Idoso , Resultado do Tratamento , Fatores de Tempo , Estudos Retrospectivos , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/efeitos dos fármacos
6.
Cardiovasc Diabetol ; 23(1): 179, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802898

RESUMO

BACKGROUND: Stress hyperglycemia, which is associated with poor prognosis in patients with acute myocardial infarction (AMI), can be determined using the stress hyperglycemia ratio (SHR). Impaired left ventricular function and microvascular obstruction (MVO) diagnosed using cardiac magnetic resonance (CMR) have also been proven to be linked to poor prognosis in patients with AMI and aid in risk stratification. However, there have been no studies on the correlation between fasting SHR and left ventricular function and MVO in patients with acute ST-segment elevation myocardial infarction (ASTEMI). Therefore, this study aimed to investigate the additive effect of fasting SHR on left ventricular function and global deformation in patients with ASTEMI and to explore the association between fasting SHR and MVO. METHODS: Consecutive patients who underwent CMR at index admission (3-7 days) after primary percutaneous coronary intervention (PPCI) were enrolled in this study. Basic clinical, biochemical, and CMR data were obtained and compared among all patients grouped by fasting SHR tertiles: SHR1: SHR < 0.85; SHR2: 0.85 ≤ SHR < 1.01; and SHR3: SHR ≥ 1.01. Spearman's rho (r) was used to assess the relationship between fasting SHR and left ventricular function, myocardial strain, and the extent of MVO. Multivariable linear regression analysis was performed to evaluate the determinants of left ventricular function and myocardial strain impairment in all patients with AMI. Univariable and multivariable regression analyses were performed to investigate the correlation between fasting SHR and the presence and extent of MVO in patients with AMI and those with AMI and diabetes mellitus (DM). RESULTS: A total of 357 patients with ASTEMI were enrolled in this study. Left ventricular ejection fraction (LVEF) and left ventricular global function index (LVGFI) were significantly lower in SHR2 and SHR3 than in SHR1. Compared with SHR1 and SHR2 groups, left ventricular strain was lower in SHR3, as evidenced by global radial (GRS), global circumferential (GCS), and global longitudinal (GLS) strains. Fasting SHR were negatively correlated with LVEF, LVGFI, and GRS (r = - 0.252; r = - 0.261; and r = - 0.245; all P<0.001) and positively correlated with GCS (r = 0.221) and GLS (r = 0.249; all P <0.001). Multivariable linear regression analysis showed that fasting SHR was an independent determinant of impaired LVEF, LVGFI, GRS, and GLS. Furthermore, multivariable regression analysis after adjusting for covariates signified that fasting SHR was associated with the presence and extent of MVO in patients with AMI and those with AMI and DM. CONCLUSION: Fasting SHR in patients with ASTEMI successfully treated using PPCI is independently associated with impaired cardiac function and MVO. In patients with AMI and DM, fasting SHR is an independent determinant of the presence and extent of MVO.


Assuntos
Glicemia , Circulação Coronária , Hiperglicemia , Microcirculação , Valor Preditivo dos Testes , Infarto do Miocárdio com Supradesnível do Segmento ST , Função Ventricular Esquerda , Humanos , Masculino , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Pessoa de Meia-Idade , Feminino , Idoso , Glicemia/metabolismo , Hiperglicemia/sangue , Hiperglicemia/fisiopatologia , Hiperglicemia/diagnóstico , Hiperglicemia/complicações , Fatores de Risco , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Intervenção Coronária Percutânea/efeitos adversos , Biomarcadores/sangue , Jejum/sangue , Imagem Cinética por Ressonância Magnética , Prognóstico , Imageamento por Ressonância Magnética , Fatores de Tempo
8.
J Magn Reson Imaging ; 59(1): 164-176, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37013673

RESUMO

BACKGROUND: Poorly controlled type 2 diabetes mellitus (T2DM) is known to result in left ventricular (LV) dysfunction, myocardial fibrosis, and ischemic/nonischemic dilated cardiomyopathy (ICM/NIDCM). However, less is known about the prognostic value of T2DM on LV longitudinal function and late gadolinium enhancement (LGE) assessed with cardiac MRI in ICM/NIDCM patients. PURPOSE: To measure LV longitudinal function and myocardial scar in ICM/NIDCM patients with T2DM and to determine their prognostic values. STUDY TYPE: Retrospective cohort. POPULATION: Two hundred thirty-five ICM/NIDCM patients (158 with T2DM and 77 without T2DM). FIELD STRENGTH/SEQUENCE: 3T; steady-state free precession cine; phase-sensitive inversion recovery segmented gradient echo LGE sequences. ASSESSMENT: Global peak longitudinal systolic strain rate (GLPSSR) was evaluated to LV longitudinal function with feature tracking. The predictive value of GLPSSR was determined with ROC curve. Glycated hemoglobin (HbA1c) was measured. The primary adverse cardiovascular endpoint was follow up every 3 months. STATISTICAL TESTS: Mann-Whitney U test or student's t-test; Intra and inter-observer variabilities; Kaplan-Meier method; Cox proportional hazards analysis (threshold = 5%). RESULTS: ICM/NIDCM patients with T2DM exhibited significantly lower absolute value of GLPSSR (0.39 ± 0.14 vs. 0.49 ± 0.18) and higher proportion of LGE positive (+) despite similar LV ejection fraction, compared to without T2DM. LV GLPSSR was able to predict primary endpoint (AUC 0.73) and optimal cutoff point was 0.4. ICM/NIDCM patients with T2DM (GLPSSR < 0.4) had more markedly impaired survival. Importantly, this group (GLPSSR < 0.4, HbA1c ≥ 7.8%, or LGE (+)) exhibited the worst survival. In multivariate analysis, GLPSSR, HbA1c, and LGE (+) significantly predicted primary adverse cardiovascular endpoint in overall ICM/NIDCM and ICM/NIDCM patients with T2DM. CONCLUSIONS: T2DM has an additive deleterious effect on LV longitudinal function and myocardial fibrosis in ICM/NIDCM patients. Combining GLPSSR, HbA1c, and LGE could be promising markers in predicting outcomes in ICM/NIDCM patients with T2DM. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: 5.


Assuntos
Cardiomiopatias , Cardiomiopatia Dilatada , Diabetes Mellitus Tipo 2 , Disfunção Ventricular Esquerda , Humanos , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/diagnóstico por imagem , Prognóstico , Estudos Retrospectivos , Diabetes Mellitus Tipo 2/complicações , Meios de Contraste , Hemoglobinas Glicadas , Imagem Cinética por Ressonância Magnética/métodos , Gadolínio , Função Ventricular Esquerda , Fibrose , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/diagnóstico por imagem , Isquemia
9.
Theor Appl Genet ; 137(8): 190, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39043952

RESUMO

KEY MESSAGE: Extensive and comprehensive phenotypic data from a maize RIL population under both low- and normal-Pi treatments were used to conduct QTL mapping. Additionally, we integrated parental resequencing data from the RIL population, GWAS results, and transcriptome data to identify candidate genes associated with low-Pi stress in maize. Phosphorus (Pi) is one of the essential nutrients that greatly affect the maize yield. However, the genes underlying the QTL controlling maize low-Pi response remain largely unknown. In this study, a total of 38 traits at both seedling and maturity stages were evaluated under low- and normal-Pi conditions using a RIL population constructed from X178 (tolerant) and 9782 (sensitive), and most traits varied significantly between low- and normal-Pi treatments. Twenty-nine QTLs specific to low-Pi conditions were identified after excluding those with common intervals under both low- and normal-Pi conditions. Furthermore, 45 additional QTLs were identified based on the index value ((Trait_under_LowPi-Trait_under_NormalPi)/Trait_under_NormalPi) of each trait. These 74 QTLs collectively were classified as Pi-dependent QTLs. Additionally, 39 Pi-dependent QTLs were clustered in nine HotspotQTLs. The Pi-dependent QTL interval contained 19,613 unique genes, 6,999 of which exhibited sequence differences with non-synonymous mutation sites between X178 and 9782. Combined with in silico GWAS results, 277 consistent candidate genes were identified, with 124 genes located within the HotspotQTL intervals. The transcriptome analysis revealed that 21 genes, including the Pi transporter ZmPT7 and the strigolactones pathway-related gene ZmPDR1, exhibited consistent low-Pi stress response patterns across various maize inbred lines or tissues. It is noteworthy that ZmPDR1 in maize roots can be sharply up-regulated by low-Pi stress, suggesting its potential importance as a candidate gene for responding to low-Pi stress through the strigolactones pathway.


Assuntos
Mapeamento Cromossômico , Fósforo , Locos de Características Quantitativas , Zea mays , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Mapeamento Cromossômico/métodos , Fósforo/metabolismo , Fenótipo , Sequenciamento de Nucleotídeos em Larga Escala , Genes de Plantas , Genoma de Planta , Regulação da Expressão Gênica de Plantas , Simulação por Computador
10.
PLoS Biol ; 19(5): e3001209, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33961621

RESUMO

The ongoing Coronavirus Disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) threatens global public health and economy unprecedentedly, requiring accelerating development of prophylactic and therapeutic interventions. Molecular understanding of neutralizing antibodies (NAbs) would greatly help advance the development of monoclonal antibody (mAb) therapy, as well as the design of next generation recombinant vaccines. Here, we applied H2L2 transgenic mice encoding the human immunoglobulin variable regions, together with a state-of-the-art antibody discovery platform to immunize and isolate NAbs. From a large panel of isolated antibodies, 25 antibodies showed potent neutralizing activities at sub-nanomolar levels by engaging the spike receptor-binding domain (RBD). Importantly, one human NAb, termed PR1077, from the H2L2 platform and 2 humanized NAb, including PR953 and PR961, were further characterized and subjected for subsequent structural analysis. High-resolution X-ray crystallography structures unveiled novel epitopes on the receptor-binding motif (RBM) for PR1077 and PR953, which directly compete with human angiotensin-converting enzyme 2 (hACE2) for binding, and a novel non-blocking epitope on the neighboring site near RBM for PR961. Moreover, we further tested the antiviral efficiency of PR1077 in the Ad5-hACE2 transduction mouse model of COVID-19. A single injection provided potent protection against SARS-CoV-2 infection in either prophylactic or treatment groups. Taken together, these results shed light on the development of mAb-related therapeutic interventions for COVID-19.


Assuntos
Anticorpos Neutralizantes/imunologia , COVID-19/virologia , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Neutralizantes/metabolismo , Anticorpos Neutralizantes/ultraestrutura , Anticorpos Antivirais/imunologia , COVID-19/epidemiologia , COVID-19/imunologia , COVID-19/metabolismo , Epitopos/imunologia , Humanos , Camundongos , Camundongos Transgênicos , Testes de Neutralização , Pandemias , Ligação Proteica , Domínios Proteicos , Receptores Virais/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia
11.
Eur Radiol ; 34(1): 485-494, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37540319

RESUMO

OBJECTIVES: To investigate the MRI radiomics signatures in predicting pathologic response among patients with locally advanced esophageal squamous cell carcinoma (ESCC), who received neoadjuvant chemotherapy (NACT). METHODS: Patients who underwent NACT from March 2015 to October 2019 were prospectively included. Each patient underwent esophageal MR scanning within one week before NACT and within 2-3 weeks after completion of NACT, prior to surgery. Radiomics features extracted from T2-TSE-BLADE were randomly split into the training and validation sets at a ratio of 7:3. According to the progressive tumor regression grade (TRG), patients were stratified into two groups: good responders (GR, TRG 0 + 1) and poor responders (non-GR, TRG 2 + 3). We constructed the Pre/Post-NACT model (Pre/Post-model) and the Delta-NACT model (Delta-model). Kruskal-Wallis was used to select features, logistic regression was used to develop the final model. RESULTS: A total of 108 ESCC patients were included, and 3/2/4 out of 107 radiomics features were selected for constructing the Pre/Post/Delta-model, respectively. The selected radiomics features were statistically different between GR and non-GR groups. The highest area under the curve (AUC) was for the Delta-model, which reached 0.851 in the training set and 0.831 in the validation set. Among the three models, Pre-model showed the poorest performance in the training and validation sets (AUC, 0.466 and 0.596), and the Post-model showed better performance than the Pre-model in the training and validation sets (AUC, 0.753 and 0.781). CONCLUSIONS: MRI-based radiomics models can predict the pathological response after NACT in ESCC patients, with the Delta-model exhibiting optimal predictive efficacy. CLINICAL RELEVANCE STATEMENT: MRI radiomics features could be used as a useful tool for predicting the efficacy of neoadjuvant chemotherapy in esophageal carcinoma patients, especially in selecting responders among those patients who may be candidates to benefit from neoadjuvant chemotherapy. KEY POINTS: • The MRI radiomics features based on T2WI-TSE-BLADE could potentially predict the pathologic response to NACT among ESCC patients. • The Delta-model exhibited the best predictive ability for pathologic response, followed by the Post-model, which similarly had better predictive ability, while the Pre-model performed less well in predicting TRG.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/tratamento farmacológico , Terapia Neoadjuvante , Radiômica , Imageamento por Ressonância Magnética , Estudos Retrospectivos
12.
Eur Radiol ; 34(8): 4963-4976, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38252276

RESUMO

OBJECTIVE: We aimed to evaluate the mitral valve calcification and mitral structure detected by cardiac computed tomography (cardiac CT) and establish a scoring model based on cardiac CT and clinical factors to predict early good mitral valve repair (EGMR) and guide surgical strategy in rheumatic mitral disease (RMD). MATERIALS AND METHODS: This is a retrospective bi-center cohort study. Based on cardiac CT, mitral valve calcification and mitral structure in RMD were quantified and evaluated. The primary outcome was EGMR. A logical regression algorithm was applied to the scoring model. RESULTS: A total of 579 patients were enrolled in our study from January 1, 2019, to August 31, 2022. Of these, 443 had baseline cardiac CT scans of adequate quality. The calcification quality score, calcification and thinnest part of the anterior leaflet clean zone, and papillary muscle symmetry were the independent CT factors of EGMR. Coronary artery disease and pulmonary artery pressure were the independent clinical factors of EGMR. Based on the above six factors, a scoring model was established. Sensitivity = 95% and specificity = 95% were presented with a cutoff value of 0.85 and 0.30 respectively. The area under the receiver operating characteristic of external validation set was 0.84 (95% confidence interval [CI] 0.73-0.93). CONCLUSIONS: Mitral valve repair is recommended when the scoring model value > 0.85 and mitral valve replacement is prior when the scoring model value < 0.30. This model could assist in guiding surgical strategies for RMD. CLINICAL RELEVANCE STATEMENT: The model established in this study can serve as a reference indicator for surgical repair in rheumatic mitral valve disease. KEY POINTS: • Cardiac CT can reflect the mitral structure in detail, especially for valve calcification. • A model based on cardiac CT and clinical factors for predicting early good mitral valve repair was established. • The developed model can help cardiac surgeons formulate appropriate surgical strategies.


Assuntos
Valva Mitral , Cardiopatia Reumática , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Cardiopatia Reumática/diagnóstico por imagem , Cardiopatia Reumática/cirurgia , Estudos Retrospectivos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Calcinose/diagnóstico por imagem , Calcinose/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Adulto , Valor Preditivo dos Testes , Estudos de Coortes
13.
J Nanobiotechnology ; 22(1): 104, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468289

RESUMO

Modulating macrophages presents a promising avenue in tumor immunotherapy. However, tumor cells have evolved mechanisms to evade macrophage activation and phagocytosis. Herein, we introduced a bispecific antibody-based nanoengager to facilitate the recognition and phagocytosis of tumor cells by macrophages. Specifically, we genetically engineered two single chain variable fragments (scFv) onto cell membrane: anti-CD40 scFv for engaging with macrophages and anti-Claudin18.2 (CLDN18.2) scFv for interacting with tumor cells. These nanoengagers were further constructed by coating scFv-anchored membrane into PLGA nanoparticle core. Our developed nanoengagers significantly boosted immune responses, including increased recognition and phagocytosis of tumor cells by macrophages, enhanced activation and antigen presentation, and elevated cytotoxic T lymphocyte activity. These combined benefits resulted in enhancing antitumor efficacy against highly aggressive "cold" pancreatic cancer. Overall, this study offers a versatile nanoengager design for immunotherapy, achieved through genetically engineering to incorporate antibody-anchored membrane.


Assuntos
Anticorpos Biespecíficos , Neoplasias , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/terapia , Imunoterapia/métodos , Engenharia Genética , Linfócitos T Citotóxicos , Claudinas
14.
J Environ Sci (China) ; 139: 496-515, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105072

RESUMO

Birnessite is ubiquitous in the natural environment where heavy metals are retained and easily transformed. The surface properties and structure of birnessite change with the changes in external environmental conditions, which also affects the fate of heavy metals. Clarifying the effect and mechanism of the birnessite phase transition process on heavy metals is the key to taking effective measures to prevent and control heavy metal pollution. Therefore, the four transformation pathways of birnessite are summarized first in this review. Second, the relationship between transformation pathways and environmental conditions is proposed. These relevant environmental conditions include abiotic (e.g., co-existing ions, pH, oxygen pressure, temperature, electric field, light, aging, pressure) and biotic factors (e.g., microorganisms, biomolecules). The phase transformation is achieved by the key intermediate of Mn(III) through interlayer-condensation, folding, neutralization-disproportionation, and dissolution-recrystallization mechanisms. The AOS (average oxidation state) of Mn and interlayer spacing are closely correlated with the phase transformation of birnessite. Last but not least, the mechanisms of heavy metals immobilization in the transformation process of birnessite are summed up. They involve isomorphous substitution, redox, complexation, hydration/dehydration, etc. The transformation of birnessite and its implication on heavy metals will be helpful for understanding and predicting the behavior of heavy metals and the crucial phase of manganese oxides/hydroxides in natural and engineered environments.


Assuntos
Manganês , Metais Pesados , Manganês/química , Adsorção , Metais Pesados/química , Óxidos/química , Compostos de Manganês/química , Oxirredução
15.
Angew Chem Int Ed Engl ; 63(2): e202313890, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38059792

RESUMO

Room-temperature phosphorescent (RTP) materials have great potential for in vivo imaging because they can circumvent the autofluorescence of biological tissues. In this study, a class of organic-doped long-wavelength (≈600 nm) RTP materials with benzo[c][1,2,5] thiadiazole as a guest was constructed. Both host and guest molecules have simple structures and can be directly purchased commercially at a low cost. Owing to the long phosphorescence wavelength of the doping system, it exhibited good tissue penetration (10 mm). Notably, these RTP nanoparticles were successfully used to image atherosclerotic plaques, with a signal-to-background ratio (SBR) of 44.52. This study provides a new approach for constructing inexpensive red organic phosphorescent materials and a new method for imaging cardiovascular diseases using these materials.


Assuntos
Doenças Cardiovasculares , Nanopartículas , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/diagnóstico por imagem , Temperatura , Diagnóstico por Imagem
16.
BMC Genomics ; 24(1): 712, 2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007417

RESUMO

BACKGROUND: Recombination reshuffles alleles at linked loci, allowing genes to evolve independently and consequently enhancing the efficiency of selection. This makes quantifying recombination along chromosomes an important goal for understanding how selection and drift are acting on genes and chromosomes. RESULTS: We present RecView, an interactive R application and its homonymous R package, to facilitate locating recombination positions along chromosomes or scaffolds using whole-genome genotype data of a three-generation pedigree. RecView analyses and plots the grandparent-of-origin of all informative alleles along each chromosome of the offspring in the pedigree, and infers recombination positions with either of two built-in algorithms: one based on change in the proportion of the alleles with specific grandparent-of-origin, and one on the degree of continuity of alleles with the same grandparent-of-origin. RecView handles multiple offspring and chromosomes simultaneously, and all putative recombination positions are reported in base pairs together with an estimated precision based on the local density of informative alleles. We demonstrate RecView using genotype data of a passerine bird with an available reference genome, the great reed warbler (Acrocephalus arundinaceus), and show that recombination events can be located to specific positions. CONCLUSIONS: RecView is an easy-to-use and highly effective application for locating recombination positions with high precision. RecView is available on GitHub ( https://github.com/HKyleZhang/RecView.git ).


Assuntos
Genoma , Recombinação Genética , Linhagem , Genótipo , Cromossomos
17.
Br J Haematol ; 201(3): 417-421, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35594370

RESUMO

The delivery of bispecific antibodies (BsAbs) targeting B-cell maturation antigen (BCMA) and CD3 using the gene therapy approach is a promising alternative for BsAb administration in patients with multiple myeloma (MM). In the present study, we evaluated the efficacy of this approach using a xenograft model. Tumour growth was significantly delayed in mice treated with single electroporation-enhanced intramuscular injection of plasmid DNA encoding BCMA/CD3 BsAb in contrast to the vehicle control-treated group. Limited toxicity was observed following treatment. This study demonstrates that the gene therapy-based approach for the delivery of BCMA/CD3 BsAb is effective and safe for the treatment of MM.


Assuntos
Anticorpos Biespecíficos , Mieloma Múltiplo , Humanos , Camundongos , Animais , Mieloma Múltiplo/genética , Mieloma Múltiplo/terapia , Antígeno de Maturação de Linfócitos B/genética , Linfócitos T , Complexo CD3 , Anticorpos Biespecíficos/uso terapêutico , Plasmídeos/genética
18.
Mod Pathol ; 36(6): 100141, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36813115

RESUMO

Solid pseudopapillary neoplasms (SPNs) of the pancreas are rare. They are considered low-grade malignancies, and a small percentage of patients experience recurrence or metastasis. It is critical to investigate associated biological behavior and identify patients at a risk of relapse. This was a retrospective study of 486 patients with SPNs who were diagnosed between 2000 and 2021. Their clinicopathologic features, including 23 parameters and prognoses were analyzed. Six patients (1.2%) presented with synchronous liver metastasis. A total of 21 patients experienced recurrence or metastasis postoperatively. The overall and disease-specific survival rates were 99.8% and 100%, respectively. The 5- and 10-year relapse-free survival (RFS) rates were 97.4% and 90.2%, respectively. Tumor size, lymphovascular invasion, and the Ki-67 index were independent predictors of relapse. Furthermore, a Peking Union Medical College Hospital-SPN risk model was built to evaluate the risk of relapse and compared it with the American Joint Committee on Cancer tumor staging system (eighth edition, 2017). Risk factors included 3 parameters: tumor size (>9 cm), lymphovascular invasion status (presence), and Ki-67 index (>1%). Risk grades were available for 345 patients, who were divided into 2 groups: (1) low risk (n = 124) and (2) high risk (n = 221). The group with no risk factors was designated as low risk and had a 10-year RFS of 100%. The group associated with 1 to 3 factors was designated as high risk, with a 10-year RFS of 75.3%. Receiver operating characteristic curves were generated, and the area under the curve was 0.791 for our model and 0.630 for the American Joint Committee on Cancer with respect to the cancer staging system. We validated our model in independent cohorts and demonstrated a sensitivity of 98.3%. In conclusion, SPNs are low-grade malignant neoplasms that rarely metastasize, and the 3 selected pathologic parameters can be used to predict their behavior. A novel Peking Union Medical College Hospital-SPN risk model was proposed for routine application to guide the patient counseling in clinical practice.


Assuntos
Carcinoma Papilar , Neoplasias Pancreáticas , Humanos , Estudos Retrospectivos , Antígeno Ki-67 , Neoplasias Pancreáticas/patologia , Recidiva Local de Neoplasia/patologia , Pâncreas/patologia , Carcinoma Papilar/patologia
19.
J Magn Reson Imaging ; 57(1): 167-177, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35436040

RESUMO

BACKGROUND: Diffuse myocardial interstitial fibrosis (DMIF) is a key factor for heart failure (HF) in diabetic cardiomyopathy. MRI T1-mapping technique can quantitatively evaluate DMIF. PURPOSE: To evaluate of early DMIF in a type 1 diabetes mellitus (T1DM) mouse model through 7.0 T MRI T1 mapping. STUDY TYPE: Prospective. ANIMAL MODEL: A total of 50 8-week-old C57Bl/6J male mice were divided into control (n = 20) and T1DM (n = 30) groups. FIELD STRENGTH/SEQUENCE: A 7.0 T small animal MRI; gradient echo Look-Locker inversion recovery T1-mapping sequence; cine MRI. Scans were acquired in control and T1DM mice every 4 weeks until 24 weeks. ASSESSMENT: End-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), left ventricle (LV) mass, fractional shortening (FS), and E/A ratio. They were evaluated through echocardiography and cine MRI. The extracellular volume fraction (ECV) was calculated. Sirius Red staining was performed and calculated collagen volume fraction (CVF). STATISTICAL TESTS: Differences in ECV and CVF between two groups were analyzed using one-way analysis of variance. The correlation between ECV and CVF was assessed using Pearson's correlations. RESULTS: Compared with the control group, a progressive decrease in FS, EF, and E/A ratio was observed in the T1DM group. Both ECV and CVF values gradually increased during diabetes progression. A significant increase in ECV and CVF values was observed at 12 weeks (ECV: 32.5% ± 1.6% vs. 28.1% ± 1.8%; CVF: 6.9% ± 1.8% vs. 3.3% ± 1.1%). ECV showed a strong correlation with CVF (r = 0.856). DATA CONCLUSION: ECV is an accurate and feasible imaging marker that can be used to quantitatively assess DMIF changes over time in T1DM mice. ECV has potential to accurately detect DMIF in the early stage and may be a useful imaging tool to assess the need for early intervention in T1DM mice. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 3.


Assuntos
Cardiomiopatias , Diabetes Mellitus Tipo 1 , Masculino , Camundongos , Animais , Estudos Prospectivos , Diabetes Mellitus Tipo 1/diagnóstico por imagem , Miocárdio/patologia , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/patologia , Imagem Cinética por Ressonância Magnética/métodos , Fibrose , Valor Preditivo dos Testes , Modelos Animais de Doenças , Espectroscopia de Ressonância Magnética , Função Ventricular Esquerda
20.
J Magn Reson Imaging ; 58(3): 907-923, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36527425

RESUMO

BACKGROUND: Current radiomics for treatment response assessment in gastric cancer (GC) have focused solely on Computed tomography (CT). The importance of multi-parametric magnetic resonance imaging (mp-MRI) radiomics in GC is less clear. PURPOSE: To compare and combine CT and mp-MRI radiomics for pretreatment identification of pathological response to neoadjuvant chemotherapy in GC. STUDY TYPE: Retrospective. POPULATION: Two hundred twenty-five GC patients were recruited and split into training (157) and validation dataset (68) in the ratio of 7:3 randomly. FIELD/SEQUENCE: T2-weighted fast spin echo (fat suppressed T2-weighted imaging [fs-T2WI]), diffusion weighted echo planar imaging (DWI), and fast gradient echo (dynamic contrast enhanced [DCE]) sequences at 3.0T. ASSESSMENT: Apparent diffusion coefficient (ADC) maps were generated from DWI. CT, fs-T2WI, ADC, DCE, and mp-MRI Radiomics score (Radscores) were compared between responders and non-responders. A multimodal nomogram combining CT and mp-MRI Radscores was developed. Patients were followed up for 3-65 months (median 19) after surgery, the overall survival (OS) and progression free survival (PFS) were calculated. STATISTICAL TESTS: A logistic regression classifier was applied to construct the five models. Each model's performance was evaluated using a receiver operating characteristic curve. The association of the nomogram with OS/PFS was evaluated by Kaplan-Meier survival analysis and C-index. A P value <0.05 was considered statistically significant. RESULTS: CT Radscore, mp-MRI Radscore and nomogram were significantly associated with tumor regression grading. The nomogram achieved the highest area under the curves (AUCs) of 0.893 (0.834-0.937) and 0.871 (0.767-0.940) in training and validation datasets, respectively. The C-index was 0.589 for OS and 0.601 for PFS. The AUCs of the mp-MRI model were not significantly different to that of the CT model in training (0.831 vs. 0.770, P = 0.267) and validation dataset (0.797 vs. 0.746, P = 0.137). DATA CONCLUSIONS: mp-MRI radiomics provides similar results to CT radiomics for early identification of pathologic response to neoadjuvant chemotherapy. The multimodal radiomics nomogram further improved the capability. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: 2.


Assuntos
Neoplasias Gástricas , Humanos , Imageamento por Ressonância Magnética/métodos , Terapia Neoadjuvante/métodos , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/tratamento farmacológico , Tomografia Computadorizada por Raios X
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