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1.
Metab Eng ; 82: 29-40, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38224832

RESUMO

Yarrowia lipolytica is widely used in biotechnology to produce recombinant proteins, food ingredients and diverse natural products. However, unstable expression of plasmids, difficult and time-consuming integration of single and low-copy-number plasmids hampers the construction of efficient production pathways and application to industrial production. Here, by exploiting sequence diversity in the long terminal repeats (LTRs) of retrotransposons and ribosomal DNA (rDNA) sequences, a set of vectors and methods that can recycle multiple and high-copy-number plasmids was developed that can achieve stable integration of long-pathway genes in Y. lipolytica. By combining these sequences, amino acids and antibiotic tags with the Cre-LoxP system, a series of multi-copy site integration recyclable vectors were constructed and assessed using the green fluorescent protein (HrGFP) reporter system. Furthermore, by combining the consensus sequence with the vector backbone of a rapidly degrading selective marker and a weak promoter, multiple integrated high-copy-number vectors were obtained and high levels of stable HrGFP expression were achieved. To validate the universality of the tools, simple integration of essential biosynthesis modules was explored, and 7.3 g/L of L-ergothioneine and 8.3 g/L of (2S)-naringenin were achieved in a 5 L fermenter, the highest titres reported to date for Y. lipolytica. These novel multi-copy genome integration strategies provide convenient and effective tools for further metabolic engineering of Y. lipolytica.


Assuntos
Yarrowia , Yarrowia/genética , Yarrowia/metabolismo , Plasmídeos/genética , Engenharia Metabólica , Biotecnologia , Proteínas Recombinantes/genética
2.
Opt Express ; 32(10): 16761-16776, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38858874

RESUMO

The small imaging size of targets over long distances results in the loss of geometry and spatial features. Current methods are subject to sampling limitations and cannot accurately capture the spatial features of sub-pixel targets. This paper proposes a method to accurately locate and extract the fine spatial features of sub-pixel targets through aperture coding and micro-scanning imaging. First, the formation mechanism of imaging features for sub-pixel targets is analyzed. Second, the optical aperture is anisotropically coded in different directions to modulate the spreading spots of the target. The primary spreading direction and the center of the anisotropic spreading spots are extracted. The contour and the location of the target are determined from the spreading length and the intersections of the primary spreading directions. Then, the target is sampled by different detector units through various micro-scanning offsets. The pixel units containing different sub-pixel components of the target after offset are determined based on the location results. The fine spatial distribution of the sub-pixel target is reconstructed based on the intensity variations in the pixel units containing the target. Finally, the accuracy of the sub-pixel target fine spatial feature extraction method is validated. The results show a sub-pixel localization error of less than 0.02 and an effective improvement of the sub-pixel target spatial resolution. This paper provides significant potential for improving the ability to capture spatial features of targets over long distances.

3.
Sensors (Basel) ; 24(6)2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38544045

RESUMO

Trafficability gives tracked vehicles adaptability, stability, and propulsion for various purposes, including deep-sea research in rough terrain. Terrain characteristics affect tracked vehicle mobility. This paper investigates the soil mechanical interaction dynamics between rubber-tracked vehicles and sedimental soils through controlled laboratory-simulated experiments. Focusing on Bentonite and Diatom sedimental soils, which possess distinct shear properties from typical land soils, the study employs innovative user-written subroutines to characterize mechanical models linked to the RecurDyn simulation environment. The experiment is centered around a dual-tracked crawler, which in itself represents a fully independent vehicle. A new three-dimensional multi-body dynamic simulation model of the tracked vehicle is developed, integrating the moist terrain's mechanical model. Simulations assess the vehicle's trafficability and performance, revealing optimal slip ratios for maximum traction force. Additionally, a mathematical model evaluates the vehicle's tractive trafficability based on slip ratio and primary design parameters. The study offers valuable insights and a practical simulation modeling approach for assessing trafficability, predicting locomotion, optimizing design, and controlling the motion of tracked vehicles across diverse moist terrain conditions. The focus is on the critical factors influencing the mobility of tracked vehicles, precisely the sinkage speed and its relationship with pressure. The study introduces a rubber-tracked vehicle, pressure, and moisture sensors to monitor pressure sinkage and moisture, evaluating cohesive soils (Bentonite/Diatom) in combination with sand and gravel mixtures. Findings reveal that higher moisture content in Bentonite correlates with increased track slippage and sinkage, contrasting with Diatom's notable compaction and sinkage characteristics. This research enhances precision in terrain assessment, improves tracked vehicle design, and advances terrain mechanics comprehension for off-road exploration, offering valuable insights for vehicle design practices and exploration endeavors.

4.
Eur J Dent Educ ; 28(2): 461-470, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37929773

RESUMO

INTRODUCTION: The rise of virtual simulation technology and dental simulators has created a new pedagogical approach for undergraduate medical education. The purpose of this study is to evaluate the effect of virtual simulation (VS) technology on improving the students' comprehensive abilities in periodontal probing teaching in pre-practicum periodontology, such as increasing the accuracy of probing, tactile perception and performance on force control. MATERIALS AND METHODS: Twenty students were randomly selected among the fourth-year students and equally divided into VS technology teaching group (VS group) and traditional teaching group (TT group) by drawing half lots. One day later, students were required to probe the periodontal pathology model. The consistency rate between PD measurements and PD reference values, time consumption and final exam scores were recorded and statistically analysed using an unpaired Student's t test and p < .05 was considered statistical significance. Finally, questionnaires relating to teaching methods evaluation and the fidelity of the digital VS training system were distributed to students and teachers. RESULTS: VS group had a significantly higher consistency rate (72.976 ± 6.811%) than TT group (64.107 ± 4.988%, p = .004). To specify, the difference of consistency rates between the two groups in posterior teeth was larger than anterior teeth. Similarly, a larger difference was also found in proximal surfaces compared with buccal-lingual surfaces. As the pocket depth increased, the difference between the two groups increased too. These results indicated that VS is more efficient in complicated parts of periodontal probing teaching. In addition, students in VS group spent less time and gained a higher score than TT group (p < .05). The overall satisfaction rating in VS group was significantly higher than TT group. Lastly, teachers gave significant lower scores than students concerning the fidelity of VS system. CONCLUSION: Although there are much to improve, VS technology has obvious advantages in periodontal probing teaching in pre-practicum periodontology.


Assuntos
Educação em Odontologia , Estudantes , Humanos , Educação em Odontologia/métodos , Periodontia/educação , Simulação por Computador , Tecnologia , Ensino
5.
Cancer ; 129(19): 2999-3009, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37449788

RESUMO

BACKGROUND: The role of carbohydrate antigen 19-9 (CA 19-9) in response assessment among patients with intrahepatic cholangiocarcinoma (iCCA) remains unknown. The authors studied the association of the CA 19-9 response (defined as a reduction >50% from baseline) with the radiologic response and the outcome in patients with unresectable iCCA. METHODS: A prospective cohort of 422 patients who were initially diagnosed with unresectable iCCA, had baseline CA 19-9 levels ≥100 U/mL, and received treatment with systemic therapies at the authors' institution between January 2017 and December 2021 were enrolled in this study. The radiologic response was assessed using the Response Evaluation Criteria in Solid Tumors version 1.1. A landmark assessment of the CA 19-9 response and the radiologic response was performed. The associations between CA 19-9 response and imaging response, progression-free survival (PFS), and overall survival (OS) were analyzed. RESULTS: Two hundred sixty-seven patients (63.3%) had a CA 19-9 response. A CA 19-9 response was observed in 123 of 132 (93.2%) radiologic responders and in 144 of 290 (49.7%) radiologic nonresponders (p < .001). CA 19-9 responders outperformed nonresponders in median PFS (10.6 vs. 3.6 months; hazard ratio [HR], 4.8 months; 95% confidence interval [CI], 3.8-6.0 months; p < .001) and OS (21.4 vs. 6.3 months; HR, 5.3 months; 95% CI, 4.2-6.7 months; p < .001). The common independent predictors of both OS and PFS included metastasis, CA 19-9 nonresponder status, and radiologic nonresponder status in multivariable analysis. CONCLUSIONS: CA 19-9 response is a valuable addition to assess tumor response and is associated with improved outcomes in patients with iCCA. Achieving a CA 19-9 response should be one of the therapeutic objectives of patients with iCCA after systemic therapies. PLAIN LANGUAGE SUMMARY: A decline in carbohydrate antigen 19-9 levels from elevated baseline levels should be one of the therapeutic aims of patients with intrahepatic cholangiocarcinoma who are managed with systemic therapies.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Estudos Prospectivos , Colangiocarcinoma/tratamento farmacológico , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/patologia , Carboidratos/uso terapêutico , Estudos Retrospectivos
6.
Anal Chem ; 95(20): 7863-7871, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37159270

RESUMO

Understanding the metabolic disorders induced by nano- and microplastics in aquatic organisms at the molecular level could help us understand the potential toxicity of nano- and microplastics more thoroughly and provide a fundamental scientific basis for regulating the usage and management of plastic products. In this research, the effect of polypropylene nanoplastics (PP-NPs) and microplastics (PP-MPs) on metabolites in the tilapia liver was comprehensively investigated by internal extractive electrospray ionization mass spectrometry (iEESI-MS). A partial least-squares discriminant analysis (PLS-DA) and a one-component analysis of variance (ANOVA) were used for selecting 46 differential metabolites, including phospholipids, amino acids, peptides, carbohydrates, alkaloids, purines, pyrimidines, and nucleosides. Pathway enrichment analysis showed significant effects on glycerophospholipid metabolism, arginine and proline metabolism, and aminoacyl-tRNA biosynthesis after tilapia were exposed to PP-N/MPs. Dysregulation of these metabolites is mainly reflected in the possible induction of hepatitis, oxidative stress, and other symptoms. The application of iEESI-MS technology without sample pretreatment to the study of metabolic disorders in aquatic organisms under the interference of nano- and microplastics provides a promising analytical method for environmental toxicology research.


Assuntos
Ciclídeos , Tilápia , Poluentes Químicos da Água , Animais , Microplásticos , Espectrometria de Massas por Ionização por Electrospray/métodos , Plásticos , Polipropilenos/toxicidade , Fígado , Organismos Aquáticos , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
7.
Int J Mol Sci ; 24(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38069281

RESUMO

Salinity stands as a significant environmental stressor, severely impacting crop productivity. Plants exposed to salt stress undergo physiological alterations that influence their growth and development. Meanwhile, plants have also evolved mechanisms to endure the detrimental effects of salinity-induced salt stress. Within plants, Calcineurin B-like (CBL) proteins act as vital Ca2+ sensors, binding to Ca2+ and subsequently transmitting signals to downstream response pathways. CBLs engage with CBL-interacting protein kinases (CIPKs), forming complexes that regulate a multitude of plant growth and developmental processes, notably ion homeostasis in response to salinity conditions. This review introduces the repercussions of salt stress, including osmotic stress, diminished photosynthesis, and oxidative damage. It also explores how CBLs modulate the response to salt stress in plants, outlining the functions of the CBL-CIPK modules involved. Comprehending the mechanisms through which CBL proteins mediate salt tolerance can accelerate the development of cultivars resistant to salinity.


Assuntos
Calcineurina , Proteínas de Plantas , Proteínas de Plantas/metabolismo , Calcineurina/metabolismo , Proteínas Quinases/metabolismo , Estresse Salino , Estresse Fisiológico , Proteínas de Ligação ao Cálcio/metabolismo
8.
Connect Tissue Res ; 63(5): 485-497, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35125056

RESUMO

AIM: The aim of this study was to investigate the influence of pigment epithelium-derived factor (PEDF) on periodontal homeostasis in mice and the osteogenic differentiation of human periodontal ligament fibroblasts (PDLFs). MATERIALS AND METHODS: Micro-computed tomography and histology were performed to compare the alveolar bone volume, density, and bone-related markers between PEDF-deficient (PEDF-/-) and wild-type (WT) mice. Furthermore, after recombinant human PEDF treatment, the PDLF viability and osteogenic differentiation were examined using the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay, alkaline phosphatase (ALP) activity assay, Von Kossa staining, Alizarin red staining, real-time quantitative polymerase chain reaction (qRT-PCR), and immunoblotting. RESULTS: The alveolar bone volume and density of PEDF-/- mice were significantly lower than those of the WT mice. Higher receptor activator for nuclear factor-κB ligand (RANKL) expression and lower osteoprotegerin (OPG) expression levels were observed in the PEDF-/- group. Moreover, PEDF treatment did not affect the PDLF proliferation. PEDF dose-dependently improved mineral deposition. Compared with the control group, 250 ng/mL PEDF promoted OPG mRNA expression in PDLFs on Day 3 but inhibited RANKL, Wnt5a, GSK3b mRNA, and non-phosphorylated ß-catenin protein expression. However, 250 ng/mL PEDF had no significant effect on the expression of Wnt3a. On Day 7, after culture with 250 ng/mL PEDF in osteogenic medium, the ALP and RUNX2 protein levels were upregulated. VEGF protein expression was reduced in a dose-dependent manner after PEDF stimulation. The PEDF protein expression increased as the osteogenic induction time increased. CONCLUSION: PEDF gene knockout suppresses periodontal homeostasis in mice, and PEDF treatment induces PDLF osteogenic differentiation in vitro.


Assuntos
Fibroblastos , Fatores de Crescimento Neural , Osteogênese , Ligamento Periodontal , Serpinas , Fosfatase Alcalina/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Proteínas do Olho , Fibroblastos/citologia , Homeostase , Humanos , Camundongos , Camundongos Knockout , Fatores de Crescimento Neural/metabolismo , Ligamento Periodontal/citologia , RNA Mensageiro/metabolismo , Serpinas/metabolismo , Microtomografia por Raio-X
9.
Analyst ; 147(17): 3930-3937, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35920668

RESUMO

Direct profiling of endogenous biomolecules in tissue samples is considered as a promising approach to investigate metabolic-related toxicity in organisms induced by emerging pollutants. Herein, we report the application of internal extractive electrospray ionization mass spectrometry (iEESI-MS) to direct phospholipid profiling in the liver and spleen tissues of Nile tilapia exposed to perfluorooctanoic acid (PFOA). Combining positive and negative ion detection modes, 130 phospholipid signals were directly detected and identified by iEESI-MS in the tissues of Nile tilapia, including phosphatidyl cholines (PCs), sphingomyelins (SMs), phosphatidic acids (PAs), phosphatidyl ethanolamines (PEs), phosphatidyl glycerols (PGs), phosphatidyl inositols (PIs) and phosphatidyl serines (PSs). With the help of partial least squares discriminant analysis (PLS-DA) and one-way analysis of variance (ANOVA), several phospholipid signals showed a significant difference in the tissue of Nile tilapia between the control group and PFOA exposure groups. In addition, pathway analysis revealed that PFOA has a significant metabolic impact on the glycerophospholipid metabolism in Nile tilapia. Without complex sample preparation, iEESI-MS was applied to direct phospholipid profiling in the liver and spleen tissues of Nile tilapia treated with PFOA, which provided a promising methodology for investigating environmental toxicity and phospholipid-dysregulation caused by emerging pollutants in aquatic organisms.


Assuntos
Ciclídeos , Poluentes Ambientais , Animais , Caprilatos , Fluorocarbonos , Ácidos Fosfatídicos , Espectrometria de Massas por Ionização por Electrospray/métodos
10.
Oncologist ; 26(2): 139-146, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33145877

RESUMO

The U.S. Food and Drug Administration (FDA) granted accelerated approval to rucaparib in May 2020 for the treatment of adult patients with deleterious BRCA mutation (germline and/or somatic)-associated metastatic castrate-resistant prostate cancer (mCRPC) who have been treated with androgen receptor-directed therapy and a taxane. This approval was based on data from the ongoing multicenter, open-label single-arm trial TRITON2. The primary endpoint, confirmed objective response rate, in the 62 patients who met the above criteria, was 44% (95% confidence interval [CI]: 31%-57%). The median duration of response was not estimable (95% CI: 6.4 to not estimable). Fifty-six percent of patients had a response duration of >6 months and 15% >12 months. The safety profile of rucaparib was generally consistent with that of the class of poly-(ADP-ribose) polymerase enzyme inhibitors and other trials of rucaparib in the treatment of ovarian cancer. Deaths due to adverse events (AEs) occurred in 1.7% of patients, and 8% discontinued rucaparib because of an AE. Grade 3-4 AEs occurred in 59% of patients. No patients with prostate cancer developed myelodysplastic syndrome or acute myeloid leukemia. The trial TRITON3 in patients with mCRPC is ongoing and is planned to verify the clinical benefit of rucaparib in mCRPC. This article summarizes the FDA thought process and data supporting this accelerated approval. IMPLICATIONS FOR PRACTICE: The accelerated approval of rucaparib for the treatment of adult patients with deleterious BRCA mutation (germline and/or somatic)-associated metastatic castrate-resistant prostate cancer who have been treated with androgen receptor-directed therapy and a taxane represents the first approved therapy for this selected patient population. This approval was based on a single-arm trial demonstrating a confirmed objective response rate greater than that of available therapy with a favorable duration of response and an acceptable toxicity profile. The ongoing trial TRITON3 is verifying the clinical benefit of this drug.


Assuntos
Neoplasias Ovarianas , Neoplasias da Próstata , Adulto , Feminino , Humanos , Indóis/efeitos adversos , Masculino , Estados Unidos , United States Food and Drug Administration
11.
Ann Surg Oncol ; 28(13): 8142-8151, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34532819

RESUMO

BACKGROUND: Lymph node (LN) involvement is a critical prognostic factor in patients with gallbladder carcinoma (GBC). Controversy exists regarding optimal categorization of nodal metastasis status, including anatomical location of positive nodes (AJCC 7th N staging), number of metastatic lymph nodes (NMLN), log odds of metastatic LNs (LODDS), and lymph node ratio (LNR). METHODS: Patients who underwent curative-intent resection for GBC from six Chinese tertiary hospitals between 2008 and 2013 were analyzed retrospectively. The relative discriminative abilities of the different LN staging systems were assessed by different models including the tree-augmented naïve Bayesian (TAN) model, Cox proportional hazards regression model, and binary logistic regression model. RESULTS: A total of 226 patients were involved in this cohort. Based on the TAN model and composite importance measures, the most important factor affecting the prognosis in the different LN staging systems was NMLN. Among the four TAN models which were built with 4 metastatic LN markers and baseline variables, the accuracy of the NMLN-based prognostic model was 88.15%, higher than 7th N staging (86.44%), LNR (87.34%), and LODDS (85.19%). The Cox model based on NMLN (C-index: 0.763, AIC: 1371.62) had a higher fitness than the others (7th N staging C-index: 0.756, AIC: 1375.51; LNR C-index: 0.759, AIC: 1378.82; LODDS C-index 0.748, AIC: 1390.99). The AUCs of different staging binary logistic regression models were NMLN (0.872), LNR (0.872), 7th N staging (0.869) and LODDS (0.856), respectively. CONCLUSIONS: NMLN was the optimal LN staging system in evaluating prognosis of GBC.


Assuntos
Neoplasias da Vesícula Biliar , Teorema de Bayes , Neoplasias da Vesícula Biliar/cirurgia , Humanos , Excisão de Linfonodo , Linfonodos/cirurgia , Metástase Linfática , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos
12.
Radiol Med ; 126(2): 291-298, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32564269

RESUMO

BACKGROUND: The evaluation of brain metastases generally requires post-contrast MRI exam, but some patients have contraindication to contrast medium administration. PURPOSE: To investigate the value of the MRI diffusion tensor imaging (DTI) for detection of metastatic brain tumor. MATERIALS AND METHODS: We retrospectively analyzed the MRI data from 23 patients (13 males and 10 females) with brain metastases. The MRI protocol consisted in T1WI, T2WI, post-contrast 3DT1WI and DTI images (b = 1000) sequences. The brain metastatic lesions were counted in each of these sequences. We compared the advantages and limitations of different sequences in the brain metastases detection. The number of metastatic lesions identified on the contrast-enhanced 3DT1WI image is used as the reference. FA values were measured in the intratumoral, adjacent peritumoral and distant peritumoral edema area (PTEA) of brain metastasis, and the differences were statistically analyzed. RESULTS: DTI can detect more brain metastatic lesions rather than T1WI and T2WI. The number of brain metastases on DTI is similar to post-contrast 3D T1WI. There is no statistical difference in the FA value change between the adjacent and distant PTEA. CONCLUSION: The DTI original image can be used as an alternative examination for patients with contraindications to contrast-enhanced MRI. It has high sensitivity to intratumoral hemorrhage, which has advantage to detect brain metastatic lesions as compared with T1WI or T2WI images.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/secundário , Imagem de Tensor de Difusão/métodos , Meios de Contraste , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Biometrics ; 76(3): 811-820, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31863595

RESUMO

In biomedical studies, testing for homogeneity between two groups, where one group is modeled by mixture models, is often of great interest. This paper considers the semiparametric exponential family mixture model proposed by Hong et al. (2017) and studies the score test for homogeneity under this model. The score test is nonregular in the sense that nuisance parameters disappear under the null hypothesis. To address this difficulty, we propose a modification of the score test, so that the resulting test enjoys the Wilks phenomenon. In finite samples, we show that with fixed nuisance parameters the score test is locally most powerful. In large samples, we establish the asymptotic power functions under two types of local alternative hypotheses. Our simulation studies illustrate that the proposed score test is powerful and computationally fast. We apply the proposed score test to an UK ovarian cancer DNA methylation data for identification of differentially methylated CpG sites.


Assuntos
Modelos Estatísticos , Simulação por Computador
14.
Biometrics ; 76(1): 98-108, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31444807

RESUMO

Identifiability of statistical models is a fundamental regularity condition that is required for valid statistical inference. Investigation of model identifiability is mathematically challenging for complex models such as latent class models. Jones et al. used Goodman's technique to investigate the identifiability of latent class models with applications to diagnostic tests in the absence of a gold standard test. The tool they used was based on examining the singularity of the Jacobian or the Fisher information matrix, in order to obtain insights into local identifiability (ie, there exists a neighborhood of a parameter such that no other parameter in the neighborhood leads to the same probability distribution as the parameter). In this paper, we investigate a stronger condition: global identifiability (ie, no two parameters in the parameter space give rise to the same probability distribution), by introducing a powerful mathematical tool from computational algebra: the Gröbner basis. With several existing well-known examples, we argue that the Gröbner basis method is easy to implement and powerful to study global identifiability of latent class models, and is an attractive alternative to the information matrix analysis by Rothenberg and the Jacobian analysis by Goodman and Jones et al.


Assuntos
Biometria/métodos , Testes Diagnósticos de Rotina/estatística & dados numéricos , Análise de Classes Latentes , Modelos Estatísticos , Algoritmos , Viés , Simulação por Computador , Testes Diagnósticos de Rotina/normas , Humanos , Reprodutibilidade dos Testes
15.
Ann Stat ; 48(5): 2622-2645, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34267407

RESUMO

This paper concerns statistical inference for longitudinal data with ultrahigh dimensional covariates. We first study the problem of constructing confidence intervals and hypothesis tests for a low dimensional parameter of interest. The major challenge is how to construct a powerful test statistic in the presence of high-dimensional nuisance parameters and sophisticated within-subject correlation of longitudinal data. To deal with the challenge, we propose a new quadratic decorrelated inference function approach, which simultaneously removes the impact of nuisance parameters and incorporates the correlation to enhance the efficiency of the estimation procedure. When the parameter of interest is of fixed dimension, we prove that the proposed estimator is asymptotically normal and attains the semiparametric information bound, based on which we can construct an optimal Wald test statistic. We further extend this result and establish the limiting distribution of the estimator under the setting with the dimension of the parameter of interest growing with the sample size at a polynomial rate. Finally, we study how to control the false discovery rate (FDR) when a vector of high-dimensional regression parameters is of interest. We prove that applying the Storey (2002)'s procedure to the proposed test statistics for each regression parameter controls FDR asymptotically in longitudinal data. We conduct simulation studies to assess the finite sample performance of the proposed procedures. Our simulation results imply that the newly proposed procedure can control both Type I error for testing a low dimensional parameter of interest and the FDR in the multiple testing problem. We also apply the proposed procedure to a real data example.

16.
HPB (Oxford) ; 22(8): 1197-1205, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31843444

RESUMO

BACKGROUND: To compare outcomes of patients with arterially hyperenhancing intrahepatic cholangiocarcinomas (ICC) and arterially hypoenhancing ICCs after partial hepatectomy in a cohort with an analysis of prognostic factors. METHODS: From June 2009 to October 2011, a prospective cohort of 68 patients with single resectable ICCs (≤5 cm in diameter) underwent gadolinium contrast-enhanced dynamic-phase magnetic resonance imaging and were treated with partial hepatectomy. Patients were divided into those with arterially hyperenhancing ICCs (n = 28) or arterially hypoenhancing ICCs (n = 40). Clinic-radiologic-pathologic results and survival of these patients were compared and statistically analyzed. RESULTS: The median overall survival (OS) time was significantly longer in the arterially hyperenhancing ICCs (56.8 vs. 37.0 months) (p = 0.044). At pathologic evaluation, arterially hyperenhancing ICCs showed significantly higher microvessel count (MVC) than arterially hypoenhancing ICCs (106.2 ± 47.5 vs. 46.9 ± 21.6/mm2, p = 0.001). Arterial enhancement of ICCs was found to be an independent prognostic factor for longer survival. CONCLUSION: The presence of arterially hyperenhancing ICCs is related to higher MVC and exhibit a better OS time than arterially hypoenhancing ICCs after partial hepatectomy.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/cirurgia , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Meios de Contraste , Humanos , Microvasos/diagnóstico por imagem , Estudos Prospectivos
17.
J Cell Physiol ; 234(11): 19964-19976, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30989649

RESUMO

In this study, we aimed to investigate the molecular pathway(s) underlying the effect of metformin (MET) on the expression of matrix metalloproteinase (MMP)-2 and MMP-9. Real-time polymerase chain reaction, Western blot analysis, and gelatin zymography were used to assay the effects of MET on MMP and AMPK signaling pathways. In addition, HTOG cells were treated with miR-29b-3p/a scramble control, H19/a negative control, or MET/PBS to explore possible signaling pathway(s) underlying the inhibitory effect of MET on MMP-2/MMP-9. A rat model of polycystic ovary syndrome (PCOS) was also established to validate the molecular mechanism(s) of MET in vivo. The administration of MET suppressed the expression of MMP-9/MMP-2 and mTOR while increasing the expression of Akt and AMPK, indicating that MET reduced the expression of MMPs via the AMPK signaling pathway. Meanwhile, the H19/miR-29b-3p/MMP-9 and H19/miR-29b-3p/MMP-2 signaling pathways were implicated in PCOS, in which the interactions between H19/miR-29b-3p and MMP-9/MMP-2/miR-29b-3p were confirmed. Furthermore, the administration of MET suppressed the expression of H19 while elevating the expression of miR-29b-3p. And the role of MET in PCOS was also confirmed in vivo via examining the activity of H19 and AMPK signaling pathways in cell or serum samples collected from PCOS rats. MET exhibits a therapeutic effect in the treatment of PCOS by reducing the expression of MMPs.


Assuntos
Autofagia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Metformina/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/enzimologia , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Adenilato Quinase/metabolismo , Animais , Autofagia/efeitos dos fármacos , Sequência de Bases , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Feminino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Metformina/farmacologia , Síndrome do Ovário Policístico/sangue , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , RNA Longo não Codificante/genética , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo
18.
Oncologist ; 24(4): 563-569, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30541754

RESUMO

The U.S. Food and Drug Administration (FDA) granted accelerated approval to atezolizumab and pembrolizumab in April and May 2017, respectively, for the treatment of patients with locally advanced or metastatic urothelial carcinoma who are not eligible for cisplatin-containing chemotherapy. These approvals were based on efficacy and safety data demonstrated in the two single-arm trials, IMvigor210 (atezolizumab) and KEYNOTE-052 (pembrolizumab). The primary endpoint, confirmed objective response rate, was 23.5% (95% confidence interval [CI]: 16.2%-32.2%) in patients receiving atezolizumab and 28.6% (95% CI: 24.1%-33.5%) in patients receiving pembrolizumab. The median duration of response was not reached in either study and responses were seen regardless of PD-L1 status. The safety profiles of both drugs were generally consistent with approved agents targeting PD-1/PD-L1. Two ongoing trials (IMvigor130 and KEYNOTE-361) are verifying benefit of these drugs. Based on concerning preliminary reports from these trials, FDA revised the indications for both agents in cisplatin-ineligible patients. Both drugs are now indicated for patients not eligible for any platinum-containing chemotherapy or not eligible for cisplatin-containing chemotherapy and whose tumors/infiltrating immune cells express a high level of PD-L1. The indications for atezolizumab and pembrolizumab in patients who have received prior platinum-based therapy have not been changed. This article summarizes the FDA thought process and data supporting the accelerated approval of both agents and the subsequent revision of the indications. IMPLICATIONS FOR PRACTICE: The accelerated approvals of atezolizumab and pembrolizumab for cisplatin-ineligible patients with advanced urothelial carcinoma represent the first approved therapies for this patient population. These approvals were based on single-arm trials demonstrating reasonable objective response rates and favorable durations of response with an acceptable toxicity profile compared with available non-cisplatin-containing chemotherapy regimens. However, based on concerning preliminary reports from two ongoing phase III trials, the FDA revised the indication for both agents in cisplatin-ineligible patients. Both are now indicated either for patients not eligible for any platinum-containing chemotherapy or not eligible for cisplatin-containing chemotherapy and whose tumors have high expression of PD-L1.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Cisplatino , Aprovação de Drogas , Neoplasias Urológicas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Antígeno B7-H1/metabolismo , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Resultado do Tratamento , Estados Unidos , United States Food and Drug Administration , Neoplasias Urológicas/patologia
19.
Opt Express ; 27(15): 21380-21394, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510217

RESUMO

We theoretically implement some hyperparallel optical elements, including quantum single photon transistor, router, and dynamic random access memory (DRAM). The inevitable side leakage and the imperfect birefringence of the quantum dot (QD)-cavity mediates are taken into account, and unity fidelities of our optical elements can be achieved. The hyperparallel constructions are based on polarization and spatial degrees of freedom (DOFs) of the photon to increase the parallel efficiency, improve the capacity of channel, save the quantum resources, reduce the operation time, and decrease the environment noises. Moreover, the practical schemes are robust against the side leakage and the coupling strength limitation in the microcavities.

20.
Appl Microbiol Biotechnol ; 103(4): 1811-1822, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30617535

RESUMO

Spermidine is a common polyamine compound produced in bacteria, but its roles remain poorly understood. The bacterial SpeD encodes an S-adenosylmethionine decarboxylase that participates in spermidine synthesis. Lysobacter enzymogenes is an efficient environmental predator of crop fungal pathogens by secreting an antifungal antibiotic HSAF (heat-stable antifungal factor), while Clp is a master transcription factor essential for the antifungal activity of L. enzymogenes. In this work, we observed that speD was a close genomic neighbor of the clp gene. This genomic arrangement also seems to occur in many other bacteria, but the underlying reason remains unclear. By using L. enzymogenes OH11 as a working model, we showed that SpeD was involved in spermidine production that was essential for the L. enzymogenes antifungal activity. Spermidine altered the bacterial growth capability and HSAF production, both of which critically contributed to the L. enzymogenes antifungal activity. We further found that spermidine in L. enzymogenes was able to play a crucial, yet indirect role in maintaining the Clp level in vivo, at least partially accounting for its role in the antifungal activity. Thus, our findings suggested that spermidine probably plays an uncharacterized role in maintaining the levels of the master transcription regulator Clp to optimize its role in antifungal activity in an agriculturally beneficial bacterium.


Assuntos
Antifúngicos/metabolismo , Regulação Bacteriana da Expressão Gênica , Lactamas Macrocíclicas/metabolismo , Lysobacter/genética , Lysobacter/metabolismo , Espermidina/metabolismo , Fatores de Transcrição/metabolismo , Ordem dos Genes , Genoma Bacteriano , Estabilidade Proteica , Fatores de Transcrição/química
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