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1.
J Cancer Res Ther ; 20(4): 1201-1207, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39206982

RESUMEN

OBJECTIVE: To explore the differences between clinical features and computed tomography (CT) findings of early-stage glottic cancer (EGC) with or without recurrence after transoral laser microsurgery (TLM) and to establish a preoperative nomogram to predict postoperative recurrence. METHODS: The clinical and CT features of 168 consecutive patients with EGC with or without recurrence were analyzed retrospectively. Multivariate logistic regression analysis was used to determine the independent predictors of recurrence. A nomogram was constructed to preoperatively predict recurrence. To assess the nomogram's performance, the C-index and calibration plot were used. RESULTS: EGCs with and without recurrence differed significantly in T-stage, depth, and normalized CT values in the arterial phase (NCTAP) and venous phase (NCTVP) (all P < 0.05). T-stage, depth, and NCTVP were independent predictors of recurrence in EGCs (all P < 0.05). The C-index (0.765, 95% confidence interval: 0.703-0.827) and calibration plot showed that the nomogram has good prediction accuracy. Nomograms based on T-stage and CT variables provided numerically predicted recurrence rates and were better than those based on only T-stage (C-index of 0.765 vs. 0.608). CONCLUSIONS: Using clinical and CT variables, we developed a novel nomogram to predict the recurrence of EGC before TLM, which may be a potential noninvasive tool for guiding personalized treatment.


Asunto(s)
Glotis , Neoplasias Laríngeas , Terapia por Láser , Microcirugia , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Nomogramas , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/cirugía , Persona de Mediana Edad , Tomografía Computarizada por Rayos X/métodos , Neoplasias Laríngeas/cirugía , Neoplasias Laríngeas/patología , Neoplasias Laríngeas/diagnóstico por imagen , Terapia por Láser/métodos , Microcirugia/métodos , Anciano , Glotis/patología , Glotis/cirugía , Glotis/diagnóstico por imagen , Estudios Retrospectivos , Adulto , Pronóstico
2.
Int J Biol Macromol ; 277(Pt 4): 134534, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39111464

RESUMEN

A fungal laccase-mediator system capable of high effectively oxidizing tetracyclines under a wide pH range will benefit environmental protection. This study reported a directed evolution of a laccase PIE5 to improve its performance on tetracyclines oxidization at alkaline conditions. Two mutants, namely MutA (D229N/A244V) and MutB (N123A/D229N/A244V) were obtained. Although they shared a similar optimum pH and temperature as PIE5, the two mutants displayed approximately 2- and 5-fold higher specific activity toward the mediators ABTS and guaiacol at pHs 4.0 to 6.5, respectively. Simultaneously, their catalytic efficiency increased by 8.0- and 6.4-fold compared to PIE5. At a pH range of 5-8 and 28 °C, MutA or MutB at a final concentration of 2.5 U·mL-1 degraded 77 % and 81 % of 100 mg·L-1 tetracycline within 10 min, higher than PIE5 (45 %). Furthermore, 0.1 U·mL-1 MutA or MutB completely degraded 100 mg·L-1 chlortetracycline within 6 min in the presence of 0.1 mM ABTS. At pH 8.0, MutA degraded tetracycline and chlortetracycline following the routine pathways were reported previously based on LC-MS analysis.


Asunto(s)
Lacasa , Tetraciclinas , Lacasa/genética , Lacasa/metabolismo , Lacasa/química , Tetraciclinas/química , Tetraciclinas/metabolismo , Concentración de Iones de Hidrógeno , Temperatura , Biodegradación Ambiental , Evolución Molecular Dirigida , Mutación , Cinética , Hongos/enzimología , Hongos/genética , Oxidación-Reducción
3.
Quant Imaging Med Surg ; 14(8): 5932-5945, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39144053

RESUMEN

Background: The incidence rate of thyroid nodules has reached 65%, but only 5-15% of these modules are malignant. Therefore, accurately determining the benign and malignant nature of thyroid nodules can prevent unnecessary treatment. We aimed to develop a deep-learning (DL) radiomics model based on ultrasound (US), explore its diagnostic efficacy for benign and malignant thyroid nodules, and verify whether it improved the diagnostic level of physicians. Methods: We retrospectively included 1,076 thyroid nodules from 817 patients at three institutions. The radiomics and DL features of the US images were extracted and used to construct radiomics signature (Rad_sig) and deep-learning signature (DL_sig). A Pearson correlation analysis and least absolute shrinkage and selection operator (LASSO) regression analysis were used for feature selection. Clinical US semantic signature (C_US_sig) was constructed based on clinical information and US semantic features. Next, a combined model was constructed based on the above three signatures in the form of a nomogram. The model was constructed using a development set (institution 1: 719 nodules), and the model was evaluated using two external validation sets (institution 2: 74 nodules, and institution 3: 283 nodules). The performance of the model was assessed using decision curve analysis (DCA) and calibration curves. Furthermore, the C_US_sigs of junior physicians, senior physicians, and expers were constructed. The DL radiomics model was used to assist the physicians with different levels of experience in the interpretation of thyroid nodules. Results: In the development and validation sets, the combined model showed the highest performance, with areas under the curve (AUCs) of 0.947, 0.917, and 0.929, respectively. The DCA results showed that the comprehensive nomogram had the best clinical utility. The calibration curves indicated good calibration for all models. The AUCs for distinguishing between benign and malignant thyroid nodules by junior physicians, senior physicians, and experts were 0.714-0.752, 0.740-0.824, and 0.891-0.908, respectively; however, with the assistance of DL radiomics, the AUCs reached 0.858-0.923, 0.888-0.944, and 0.912-0.919, respectively. Conclusions: The nomogram based on DL radiomics had high diagnostic efficacy for thyroid nodules, and DL radiomics could assist physicians with different levels of experience to improve their diagnostic level.

4.
Heliyon ; 9(7): e17874, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37483835

RESUMEN

Oxidative stress is essential in brain injury after intracerebral hemorrhage (ICH). Ferroptosis, iron-dependent oxidative cell death, overwhelms the antioxidant system. Recently, Olfactory mucosa-derived mesenchymal stem cells (OM-MSCs) hold great potential for treating ferroptosis-mediated oxidative brain damage after ICH. However, massive grafted cell death, possibly caused by a hostile host brain microenvironment, lessens the effectiveness of OM-MSCs. Therefore, it is necessary to develop strategies to upregulate the therapeutic efficacy of OM-MSCs in ICH. Curcumin, a well-established traditional herbal substance, has potent antioxidant property. In the present study, curcumin preconditioning might enhance the anti-oxidative activity of OM-MSCs, thereby augmenting the therapeutic efficacy of OM-MSCs in ICH. In vitro model of ICH, we demonstrated that curcumin-preconditioned OM-MSCs co-culture is more effective in attenuating the cell injury, oxidative stress, and ferroptosis of neuronal cells compared to the native OM-MSCs treatment. In vivo model of ICH, transplantation of curcumin-preconditioned OM-MSCs also showed better neuroprotective effects. Moreover, curcumin pretreatment promoted the survival of OM-MSCs under a conditioned medium from hemin-insulted neurons by improving the anti-oxidative capacities of OM-MSCs. Collectively, our investigation suggested that curcumin preconditioning effectively enhanced the survival and neuroprotective effects of OM-MSCs in the ICH model by upregulating the anti-oxidative capacities of OM-MSCs. Curcumin-preconditioned OM-MSCs might be taken as a novel therapeutic strategy for treating ICH.

5.
Front Oncol ; 12: 916526, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35734603

RESUMEN

Objective: To explore the value of a predictive model combining the multiparametric magnetic resonance imaging (mpMRI) radiomics score (RAD-score), clinicopathologic features, and morphologic features for the pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) in invasive breast carcinoma of no specific type (IBC-NST). Methods: We enrolled, retrospectively and consecutively, 206 women with IBC-NST who underwent surgery after NAC and obtained pathological results from August 2018 to October 2021. Four RAD-scores were constructed for predicting the pCR based on fat-suppression T2-weighted imaging (FS-T2WI), diffusion-weighted imaging (DWI), contrast-enhanced T1-weighted imaging (T1WI+C) and their combination, which was called mpMRI. The best RAD-score was combined with clinicopathologic and morphologic features to establish a nomogram model through binary logistic regression. The predictive performance of the nomogram was evaluated using the area under receiver operator characteristic (ROC) curve (AUC) and calibration curve. The clinical net benefit of the model was evaluated using decision curve analysis (DCA). Results: The mpMRI RAD-score had the highest diagnostic performance, with AUC of 0.848 among the four RAD-scores. T stage, human epidermal growth factor receptor-2 (HER2) status, RAD-score, and roundness were independent factors for predicting the pCR (P < 0.05 for all). The combined nomogram model based on these factors achieved AUCs of 0.930 and 0.895 in the training cohort and validation cohort, respectively, higher than other models (P < 0.05 for all). The calibration curve showed that the predicted probabilities of the nomogram were in good agreement with the actual probabilities, and DCA indicated that it provided more net benefit than the treat-none or treat-all scheme by decision curve analysis in both training and validation datasets. Conclusion: The combined nomogram model based on the mpMRI RAD-score combined with clinicopathologic and morphologic features may improve the predictive performance for the pCR of NAC in patients with IBC-NST.

6.
Cell Biosci ; 12(1): 42, 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35379328

RESUMEN

BACKGROUND: Neuronal death due to over-oxidative stress responses defines the pathology of cerebral ischemic/reperfusion (I/R) insult. Ferroptosis is a form of oxidative cell death that is induced by disruption of the balance between antioxidants and pro-oxidants in cells. However, the potential mechanisms responsible for cerebral I/R-induced ferroptotic neuronal death have not been conclusively determined. UBIAD1, is a newly identified antioxidant enzyme that catalyzes coenzyme Q10 (CoQ10) and vitamin K2 biosynthesis in the Golgi apparatus membrane and mitochondria, respectively. Even though UBIAD1 is a significant mediator of apoptosis in cerebral I/R challenge, its roles in ferroptotic neuronal death remain undefined. Therefore, we investigated whether ferroptotic neuronal death is involved in cerebral I/R injury. Further, we evaluated the functions and possible mechanisms of UBIAD1 in cerebral I/R-induced ferroptotic neuronal death, with a major focus on mitochondrial and Golgi apparatus dysfunctions. RESULTS: Ferroptosis occurred in cerebral I/R. Ferroptotic neuronal death promoted cerebral I/R-induced brain tissue injury and neuronal impairment. UBIAD1 was expressed in cerebral tissues and was localized in neurons, astrocytes, and microglia. Under cerebral I/R conditions overexpressed UBIAD1 significantly suppressed lipid peroxidation and ferroptosis. Moreover, upregulated UBIAD1 protected against brain tissue damage and neuronal death by alleviating I/R-mediated lipid peroxidation and ferroptosis. However, UBIAD1 knockdown reversed these changes. Enhanced UBIAD1-mediated ferroptosis elevated the antioxidative capacity by rescuing mitochondrial and Golgi apparatus dysfunction in cerebral I/R-mediated neuronal injury. They improved the morphology and biofunctions of the mitochondria and Golgi apparatus, thereby elevating the levels of SOD, T-AOC and production of CoQ10, endothelial nitric oxide synthase (eNOS)-regulated nitric oxide (NO) generation as well as suppressed MDA generation. CONCLUSIONS: The neuroprotective agent, UBIAD1, modulates I/R-mediated ferroptosis by restoring mitochondrial and Golgi apparatus dysfunction in damaged brain tissues and neurons, thereby enhancing antioxidative capacities. Moreover, the rescue of impaired mitochondrial and Golgi apparatus as a possible mechanism of regulating ferroptotic neuronal death is a potential treatment strategy for ischemic stroke.

7.
J Matern Fetal Neonatal Med ; 35(22): 4312-4317, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33261526

RESUMEN

OBJECTIVES: The purpose of this article was to explore whether the gestational age(GA)and gender could affect the size of the cisterna magna (CM). METHODS: This study that included pregnant women who were between 20 ∼ 39+6. The recorded included BPD, HC, anteroposterior diameter of CM and gender. The fetuses were divided into normal and isolated enlargement of the CM (IECM)group for statistical analysis. RESULTS: Seven hundred ninety six fetuses with normal CM, 412 cases were boys and 384 cases were girls. 73 fetuses with IECM, 59 cases were boys and 14 cases were girls. The anteroposterior diameter of the CM increased with GA during 20-26+6 weeks. After 27 weeks, the anteroposterior diameter of CM became stable. In the IECM group, the mean anteroposterior of male and female fetuses were 1.31 ± 0.18 cm and 1.24 ± 0.15 cm, respectively. The IECM fetus accounted for 8.4% of the total number of fetuses, male IECM accounted for 14.3% of normal male fetus, and female fetus was 3.6%, which showed that male fetus had a higher rate of IECM than female (χ2 = 21.6, p<.001). CONCLUSIONS: There is a gender difference between normal fetuses and IECM fetuses. Based on our finding, it is reasonable to establish the normal value of CM according to the gender difference.


Asunto(s)
Cisterna Magna , Ultrasonografía Prenatal , Cisterna Magna/diagnóstico por imagen , Femenino , Edad Gestacional , Humanos , Masculino , Embarazo , Atención Prenatal , Valores de Referencia
8.
Mitochondrial DNA B Resour ; 4(2): 2347-2348, 2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-33365537

RESUMEN

The Tibetan gazelle Procapra picticaudata is endemic to the Tibetan plateau. The species is listed as a Near Threatened (NT) species by the IUCN Red List of Threatened Animals and the Red List of China's Vertebrates. In this study, we sequenced the complete mitochondrial genome of P. picticaudata and examined its phylogenetic position with other nine species in Artiodactyla. The complete mitochondrial genome is 16,620 bp in length and contained 22 transfer RNA genes, 2 ribosomal RNA genes, 13 protein-coding genes, and 1 control region. Our data would provide reference information for further study of this species and be useful for evolutionary and phylogenetics studies for this NT species.

9.
Adv Mater ; 30(49): e1803072, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30259576

RESUMEN

Architectures of natural organisms especially plants largely determine their response to varying external conditions. Nature-inspired shape transformation of artificial materials has motivated academic research for decades due to wide applications in smart textiles, actuators, soft robotics, and drug delivery. A "self-growth" method of controlling femtosecond laser scanning on the surface of a prestretched shape-memory polymer to realize microscale localized reconfigurable architectures transformation is introduced. It is discovered that microstructures can grow out of the original surface by intentional control of localized laser heating and ablation, and resultant structures can be further tuned by adopting an asymmetric laser scanning strategy. A distinguished paradigm of reconfigurable architectures is demonstrated by combining the flexible and programmable laser technique with a smart shape-memory polymer. Proof-of-concept experiments are performed respectively in information encryption/decryption, and microtarget capturing/release. The findings reveal new capacities of architectures with smart surfaces in various interdisciplinary fields including anti-counterfeiting, microstructure printing, and ultrasensitive detection.

10.
J Agric Food Chem ; 66(4): 1008-1014, 2018 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-29300475

RESUMEN

This study presents an efficient strategy based on liquid-liquid extraction with three-phase solvent system and high speed counter-current chromatography for rapid enrichment and separation of epimers of minor bufadienolide from toad meat. The reflux extraction conditions were optimized by response surface methodology first, and a novel three-phase solvent system composed of n-hexane/methyl acetate/acetonitrile/water (3:6:5:5, v/v) was developed for liquid-liquid extraction of the crude extract. This integrative extraction process could enrich minor bufadienolide from complex matrix efficiently and minimize the loss of minor targets induced by repeated extraction with different kinds of organic solvents occurring in the classical liquid two-phase extraction. As a result, four epimers of minor bufadienolide were greatly enriched in the middle phase and total content of these epimers of minor bufadienolide was increased from 3.25% to 46.23%. Then, the enriched four epimers were separated by HSCCC with a two-phase solvent system composed of chloroform/methanol/water (4:2:2, v/v) successfully. Furthermore, we tested Na+,K+-ATPase (NKA) inhibitory effect of the four epimers. 3ß-Isomers of bufadienolide showed stronger (>8-fold) inhibitory activity than 3α-isomers. The characterization of minor bufadienolide in toad meat and their significant difference of inhibitory effect on NKA would promote the further quantitative analysis and safety evaluation of toad meat as a food source.


Asunto(s)
Bufanólidos/química , Bufanólidos/aislamiento & purificación , Bufonidae , Distribución en Contracorriente/métodos , Extracción Líquido-Líquido/métodos , Carne/análisis , Animales , Bufanólidos/farmacología , Inhibidores Enzimáticos , Isomerismo , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Solventes
11.
Org Lett ; 20(3): 534-537, 2018 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-29363978

RESUMEN

A permissive steroid glycosyltransferase (UGT74AN1) from Asclepias curassavica exhibited robust capabilities for the regiospecific C3 glycosylation of cardiotonic steroids and C21 steroid precursors, and unprecedented promiscuity toward 53 structurally diverse natural and unnatural compounds to form O-, N-, and S-glycosides, along with the catalytic reversibility for a one-pot transglycosylation reaction. These findings highlight UGT74AN1 as the first regiospecific catalyst for cardiotonic steroid C3 glycosylation and exhibit significant potential for glycosylation of diverse bioactive molecules in drug discovery.


Asunto(s)
Asclepias , Glicósidos , Glicosilación , Glicosiltransferasas , Estructura Molecular
12.
RSC Adv ; 8(10): 5071-5078, 2018 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-35542447

RESUMEN

The glycosyltransferase OleD variant as a catalyst for the glycosylation of four pairs of epimers of cardiotonic steroids (CTS) are assessed. The results of this study demonstrated that the OleD-catalyze glycosylation of CTS is significantly influenced by the configuration at C-3 and the A/B fusion mode. 3ß-OH and A/B ring cis fusion are favoured by OleD (ASP). An epoxide ring at C-14 and C-15 further increases the bioconversion rate; while an acetyl group at C-16 and lactone ring type at C-17 did not influence the biotransformation. A high conversion rate corresponded to a low K m value. A molecular docking simulation showed that filling of hydrophobic pocket II and interaction with residue Tyr115 may play an important role in the glycosylation reactions catalyzed by OleD glycosyltransferases. Furthermore, the glycosylation products showed a stronger inhibitory activity for Na+, K+-ATPase than the corresponding aglycones. This study provides the first stereoselective properties for OleD (ASP) catalyzed glycosylation.

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