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1.
J Agric Food Chem ; 71(49): 19396-19407, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38035573

RESUMEN

Plant pathogenic fungi pose a significant threat to crop yields and quality, and the emergence of fungicide resistance has further exacerbated the problem in agriculture. Therefore, there is an urgent need for efficient and environmentally friendly fungicides. In this study, we investigated the antifungal activity of (+)-Usnic acid and its inhibitory effect on crop pathogenic fungal 4-hydroxyphenylpyruvate dioxygenases (HPPDs) and determined the structure of Zymoseptoria tritici HPPD (ZtHPPD)-(+)-Usnic acid complex. Thus, the antifungal target of (+)-Usnic acid and its inhibitory basis toward HPPD were uncovered. Additionally, we discovered a potential lead fungicide possessing a novel scaffold that displayed remarkable antifungal activities. Furthermore, our molecular docking analysis revealed the unique binding mode of this compound with ZtHPPD, explaining its high inhibitory effect. We concluded that HPPD represents a promising target for the control of phytopathogenic fungi, and the new compound serves as a novel starting point for the development of fungicides and dual-purpose pesticides.


Asunto(s)
4-Hidroxifenilpiruvato Dioxigenasa , Fungicidas Industriales , Herbicidas , Fungicidas Industriales/farmacología , 4-Hidroxifenilpiruvato Dioxigenasa/química , Herbicidas/química , Antifúngicos/farmacología , Simulación del Acoplamiento Molecular , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Relación Estructura-Actividad
2.
Structure ; 31(12): 1604-1615.e8, 2023 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-37794595

RESUMEN

4-Hydroxyphenylpyruvate dioxygenase (HPPD) has attracted increasing attention as a target for treating type I tyrosinemia and other diseases with defects in tyrosine catabolism. Only one commercial drug, 2-(2-nitro-4-trifluoromethylbenzoyl)-1, 3-cyclohexanedione (NTBC), clinically treat type I tyrosinemia, but show some severe side effects in clinical application. Here, we determined the structure of human HPPD-NTBC complex, and developed new pyrazole-benzothiadiazole 2,2-dioxide hybrids from the binding of NTBC. These compounds showed improved inhibition against human HPPD, among which compound a10 was the most active candidate. The Absorption Distribution Metabolism Excretion Toxicity (ADMET) predicted properties suggested that a10 had good druggability, and was with lower toxicity than NTBC. The structure comparison between inhibitor-bound and ligand-free form human HPPD showed a large conformational change of the C-terminal helix. Furthermore, the loop 1 and α7 helix were found adopting different conformations to assist the gating of the cavity, which explains the gating mechanism of human HPPD.


Asunto(s)
Herbicidas , Tiadiazoles , Tirosinemias , Humanos , Tirosinemias/tratamiento farmacológico , Tiadiazoles/farmacología , Tiadiazoles/uso terapéutico , Pirazoles/farmacología , Inhibidores Enzimáticos/farmacología
3.
J Ovarian Res ; 16(1): 178, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37635245

RESUMEN

BACKGROUND: Oocyte maturation arrest results in female infertility and the genetic etiology of this phenotype remains largely unknown. Previous studies have proven that cyclins play a significant role in the cell cycle both in meiosis and mitosis. Cyclin B3 (CCNB3) is one of the members of the cyclin family and its function in human oocyte maturation is poorly understood. METHODS: 118 infertile patients were recruited and WES was performed for 68 independent females that experienced oocyte maturation arrest. Four mutations in CCNB3 were found and effects of these mutations were validated by Sanger sequencing and in vitro functional analyses. RESULTS: We found these mutations altered the location of cyclin B3 which affected the function of cyclin dependent kinase 1 (CDK1) and led to mouse oocyte arrested at germinal vesicle (GV) stage. And then, low CDK1 activity influenced the degradation of cadherin 1 (CDH1) and the accumulation of cell division cycle 20 (CDC20) which are two types of anaphase-promoting complex/cyclosome (APC/C) activators and act in different stages of the cell cycle. Finally, APC/C activity was downregulated due to insufficient CDC20 level and resulted in oocyte metaphase I (MI) arrest. Moreover, we also found that the addition of PP1 inhibitor Okadic acid and CDK1 inhibitor Roscovitine at corresponding stages during oocyte in vitro maturation (IVM) significantly improved the maturation rates in CCNB3 mutant cRNAs injected oocytes. The above experiments were performed in mouse oocytes. CONCLUSION: Here, we report five independent patients in which mutations in CCNB3 may be the cause of oocyte maturation arrest. Our findings shed lights on the critical role of CCNB3 in human oocyte maturation.


Asunto(s)
Proteína Quinasa CDC2 , Ciclina B , Oocitos , Animales , Femenino , Humanos , Ratones , Proteína Quinasa CDC2/genética , Ciclina B/genética , Meiosis/genética , Mutación , Fenotipo
4.
Oncology ; 100(5): 290-302, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35350032

RESUMEN

PURPOSE: Nonampullary duodenal adenocarcinoma (NADA) is a rare disease. Although several prognostic factors have been reported for this disease, they remain controversial due to their rarity. In this study, we retrospectively analyzed 54 cases of invasive NADA, focusing on the microsatellite instability (MSI) phenotype, programmed cell death-ligand 1 (PD-L1) expression, and prognostic factors. METHODS: Expression of the PD-L1 protein and cell differentiation markers in tumors was detected by immunohistochemistry. Microsatellite markers (NR-21, NR-22, NR-24, BAT-25, and BAT-26) were amplified for MSI assessment by PCR. RESULTS: The incidence of MSI in invasive NADA was 35.2%. No significant correlation between the MSI phenotype and clinicopathological factors was observed. Positive expression of PD-L1 by immune cells was common in advanced-stage disease (p = 0.054), and positive expression of PD-L1 in cancer cells correlated significantly with the histologically undifferentiated type (p = 0.016). Kaplan-Meier survival analysis demonstrated a significantly better overall survival (OS) in patients with MSI (p = 0.013) and at early-stage disease (p = 0.000) than in those with microsatellite-stable or at late tumor stages. Univariate and multivariate analyses showed that MSI (hazard ratio [HR]: 0.282, 95% confidence interval [CI]: 0.106-0.751, p = 0.011) and early tumor stage (stage I-II) (HR: 8.81, 95% CI: 2.545-30.500, p = 0.001) were independent better prognostic factors of OS. CONCLUSIONS: MSI and early tumor stage (stage I-II) were independent better prognostic factors of OS. A high proportion of MSI phenotypes and positive PD-L1 expression may be helpful for identifying immune checkpoint inhibitors as a novel therapeutic strategy.


Asunto(s)
Adenocarcinoma , Inestabilidad de Microsatélites , Adenocarcinoma/genética , Adenocarcinoma/patología , Antígeno B7-H1/metabolismo , Biomarcadores de Tumor/análisis , Biomarcadores de Tumor/genética , Humanos , Pronóstico , Estudios Retrospectivos
6.
Retina ; 41(12): 2605-2611, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34155168

RESUMEN

PURPOSE: To investigate macular microvascular characteristics imaged by optical coherence tomography angiography in patients with uveal melanoma following conbercept injections after plaque radiotherapy. METHODS: Prospective comparative analysis comprising 15 patients with uveal melanoma with conbercept injections and 30 patients without conbercept injections after plaque radiotherapy by optical coherence tomography angiography. The conbercept group received intravitreal conbercept injections at the time of plaque removal, 1 month, 3 months, 6 months , 9 months and 12 months after plaque removal (total, 6 injections). The control group had no intravitreal conbercept injection. RESULTS: After initiation of conbercept injections, superficial retinal vascular density in the whole image and parafoveal region were significantly higher at 6 months, whereas there was no significant difference at 9 months and 12 months. In analysis of variance analysis, superficial retinal vascular density in the whole image remained stable after conbercept injections (P = 0.069), whereas the superficial retinal vascular density decreased significantly after plaque radiotherapy in the control group (P = 0.011). In multivariable linear regression, a higher superficial retinal vascular density in the whole image region at 6 months was significantly associated with intravitreal conbercept injection (P = 0.018), wider tumor base (P = 0.026), and thinner tumor thickness (P = 0.04). CONCLUSION: Optical coherence tomography angiography can provide a quantitative evaluation of early retinal microvascular changes after radiotherapy. Intravitreal conbercept treatment could partly relieve the retinal vascular damage in response to radiation therapy at early stage in patients with uveal melanoma; however, it may not be able to provide long-term positive functional outcomes.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Braquiterapia , Melanoma/radioterapia , Traumatismos por Radiación/prevención & control , Proteínas Recombinantes de Fusión/administración & dosificación , Enfermedades de la Retina/prevención & control , Vasos Retinianos/fisiopatología , Neoplasias de la Úvea/radioterapia , Adulto , Anciano , Angiografía por Tomografía Computarizada , Femenino , Humanos , Inyecciones Intravítreas , Masculino , Melanoma/patología , Persona de Mediana Edad , Estudios Prospectivos , Traumatismos por Radiación/fisiopatología , Enfermedades de la Retina/fisiopatología , Tomografía de Coherencia Óptica , Neoplasias de la Úvea/patología , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores
7.
Int J Ophthalmol ; 13(9): 1467-1476, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32953588

RESUMEN

AIM: To explore the influencing factors of diabetes type 2 patients with mild non-proliferative diabetic retinopathy (NPDR) in the Kailuan area of Tangshan, Hebei Province, China. METHODS: In this non-interventional, retrospective study, 683 patients with type 2 diabetes were included in the Kailuan Diabetic Retinopathy Study involving participants with diabetes in the community-based longitudinal Kailuan Study. Based on the undilated ultra-wide field (200°; UWF) images and partial dilated digital fundus images, the diabetic retinopathy (DR) of the surveyed population was graded. Interobserver agreement was estimated by using Cohen's Kappa statistics. The main outcome indicators included gender, age, weight, height, body mass index, blood pressure, circumferences of neck, waist and hip, current smoking, levels of fasting plasma glucose (FPG), hypersensitive C-reactive protein, creatinine, and cholesterol, etc. According to different lesions' locations of patients with mild NPDR, logistic regression models were used to estimate the odds ratios (ORs) and their 95%CIs of each risk factor. RESULTS: The study group of 683 patients included 570 males and 113 females. The mean age of the patients was 62.18±9.41y. Compared with dilated fundus examinations, there was fair agreement with the level of DR identified on UWF images in 63.91% of eyes (k=0.369, 95%CI, 0.00-0.00). Detected by UWF images, there were 98 patients with mild NPDR having peripheral retinal lesions, 35 patients with mild NPDR having posterior lesions, 44 patients with mild NPDR whose lesions were detected both in and out the standard two fields area, and 336 patients with non obvious DR. Parameters that conferred a statistically significant increased risks for mild NPDR with having peripheral retinal lesions were neck circumstance (OR, 1.124; 95%CI, 1.044-1.211), and with posterior lesions were FPG (OR, 1.052; 95%CI, 1.007-1.099). CONCLUSION: UWF is an effectiveness means of DR screening. Moreover, it is necessary to evaluate peripheral diabetic retinal lesions which can help to estimate the severity of DR. The phenomenon that nonuniform and inhomogeneous distribution of DR lesions has been found. And the influencing factors in mild NPDR are differing by different lesions' locations.

8.
Sensors (Basel) ; 20(16)2020 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-32824389

RESUMEN

This study examined how users acquire spatial knowledge in an onscreen three-dimensional virtual environment when using overview maps. This experiment adopted a three (the size of overview maps) x two (the transparency of overview maps) between-subjects design. Three levels of the size of overview maps were evaluated, i.e., 1/2, 1/8, and 1/16 screen size. Comparisons between 20% transparent and 80% transparent were made. We asked 108 participants to complete spatial perception tasks and fill out questionnaires regarding their feelings. The results indicate the following: (1) The effects of the transparency of overview maps on users' spatial perception vary with the size of overview maps. The 80% transparent overview map is significantly more efficient than the 20% transparent overview map in the condition of 1/2 screen size. However, the result is opposite in the condition of 1/8 screen size. (2) Users like the 80% transparent overview map significantly better than the 20% transparent overview map in the condition of 1/2 screen size. (3) Concerning subjective evaluations of satisfaction, preference, and system usability, overview maps in the condition of 1/8 screen size are significantly better than those in the condition of 1/2 screen size.

9.
Int J Ophthalmol ; 13(4): 599-605, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32399411

RESUMEN

AIM: To measure the concentration of vascular endothelial growth factor-A (VEGF-A), and placental growth factor (PLGF) in aqueous humor of uveal melanoma patients before and after Iodine-125 plaque therapy (IPT), determine the postoperative fluctuation and evaluate associated factors in vivo. METHODS: Participants were 18 Chinese patients with uveal melanoma who were elected to IPT. Undiluted aqueous humor samples were collected at Iodine plaque implant and removal time, then stored immediately at -80°C until assayed. The concentration of VEGF-A, PLGF and other 7 cytokines comprising interleukin-2 (IL-2), IL-8, IL-10, interferon (IFN)-γ, programmed death (PD)-1, transforming growth factor (TGF)-ß1 and insulin-like growth factor (IGF)-1 in aqueous humor was measured using Raybiotech immunoassay kit, a high throughput strategy. The VEGF-A and PLGF levels were compared across preoperation and postoperation subgroups, as well as those of other 7 interleukins. Correlation and grouped analyses were conducted to determine the independent effects of clinical parameters and other cytokines on VEGF-A and PLGF concentration or fluctuation. This study set a self-control design. RESULTS: VEGF-A (P=0.038) and PLGF (P=0.026) were the only two increased cytokines after IPT. Preoperative and postoperative level of VEGF-A and PLGF (r=0.575, P=0.013; r=0.987, P<0.001) correlated with each other significantly. Level of VEGF-A (r=0.626, P=0.005; r=0.588, P=0.01) and PLGF (r=0.616, P=0.007; r=0.588, P=0.01) had positive correlation with tumor thickness consistently. Elevated VEGF-A or PLGF level were strong predictive factors of each other (P=0.007, OR=60.0). The elevated VEGF-A group showed a higher postoperative level of IFN-γ (P=0.005), IL-2 (P<0.001) and IL-10 (P=0.004) in aqueous humor. When the elevated PLGF group got similar results that a higher postoperative level of IFN-γ (P=0.007), IL-2 (P<0.001) and IL-10 (P=0.013) in aqueous humor. CONCLUSION: This study reveals that VEGF-A and PLGF in aqueous humor significantly increased with tumor thickness and radiation process in uveal melanoma patients. VEGF-A and PLGF may be crucial in uveal melanoma genesis and radiotherapy reactions. Immune mediators comprised IFN-γ, IL-2 and IL-10 could play roles in the link between inflammation and angiogenesis in uveal melanoma when exposed to radiotherapy.

10.
Invest Ophthalmol Vis Sci ; 60(10): 3689-3695, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31469896

RESUMEN

Purpose: To examine the role of ocular axial length as an ocular parameter for the prevalence and severity of diabetic retinopathy (DR). Methods: The cross-sectional Kailuan Diabetic Retinopathy Study included patients with diabetes who participated in the community-based longitudinal Kailuan Study and who had undergone ocular fundus photography. The fundus photographs were graded using the Early Treatment of Diabetic Retinopathy Study criteria. Results: The study included 1096 patients with diabetes (mean age: 60.8 ± 9.4 years; axial length: 23.37 ± 0.92 mm). In binary regression analysis, a higher DR prevalence was associated with shorter axial length (P = 0.007; odds ratio [OR]: 0.81; 95% confidence interval [CI]: 0.70, 0.95) after adjusting for longer known duration of diabetes (P = 0.02; OR: 1.13; 95%CI: 1.02, 1.24) and higher fasting blood glucose concentration (P < 0.001; OR: 1.38; 95%CI: 1.26, 1.52). A more severe DR stage was associated (regression coefficient r: 0.46) with shorter ocular axial length (P = 0.047; standardized regression coefficient ß: -0.06) after adjusting for higher fasting blood glucose (P < 0.001; ß: 0.41) and longer known duration of diabetes (P = 0.045; ß: 0.07). Longer axial length was associated with a lower DR prevalence (P = 0.003; ß: -0.10) after adjusting for younger age (P < 0.001), male sex (P < 0.001), higher body mass index (P = 0.016), and lower fasting blood glucose concentration (P = 0.036). Conclusions: After adjusting for systemic risk factors, DR prevalence decreased by 19% (95%CI: 5, 30) for each millimeter increase in axial length. With longer axial length being a surrogate for axial myopia, the marked increase in myopia prevalence worldwide may lead to a relative decrease in the prevalence and incidence of DR in future.


Asunto(s)
Longitud Axial del Ojo/fisiopatología , Retinopatía Diabética/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Glucemia/metabolismo , China/epidemiología , Estudios Transversales , Diabetes Mellitus Tipo 2/fisiopatología , Retinopatía Diabética/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo
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