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Nanozymes based on manganese oxide (MnO2) are demonstrated to be promising probes in colorimetric sensing applications. In this study, the r-MnO2/ß-MnO2 heterophase nanostructure was simply prepared by a calcination process with controllable temperature. The characterization of the nanostructured material was confirmed by SEM, UV-vis spectroscopy, Raman, TGA-DSC, and XRD analysis. The r-MnO2/ß-MnO2 exhibits a remarkably good catalytic activity in the oxidation process of 3,3',5,5'-tetramethylbenzidine (TMB) compared with the r-MnO2 or Mn2O3 nanostructure owing to its heterophase junctions. The enhanced performance of the colorimetric sensor for ascorbic acid (AA) detection was investigated using the r-MnO2/ß-MnO2 heterophase nanostructure as probe. The r-MnO2/ß-MnO2 material enhanced the monitoring of AA in the wide linear range from 1 µM to 50 µM with a limit of detection of 0.84 µM. This work presents a promising and straightforward approach for the construction of MnO2-based colorimetric sensor and their practical application in plant growth monitoring.
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As an evolutionarily conserved transcription factor, Cut-like homeobox 1 (CUX1) plays crucial roles in embryonic and nervous system development, cell differentiation, and DNA damage repair. One of its major isoforms, p110CUX1, exhibits stable DNA binding capabilities and contributes to the regulation of cell cycle progression, proliferation, migration, and invasion. While p110CUX1 has been implicated in the progression of various malignant tumors, its involvement in acute myeloid leukemia (AML) remains uncertain. This study aims to elucidate the role of p110CUX1 in AML. Our findings reveal heightened expression levels of both p110CUX1 and pyridoxal phosphatase (PDXP) in AML cell lines. Overexpression of p110CUX1 promotes AML cell proliferation while inhibiting apoptosis and differentiation, whereas knockdown of PDXP yields contrasting effects. Mechanistically, p110CUX1 appears to facilitate AML development by upregulating PDXP expression and activating the PI3K/AKT/mTOR signaling pathway. Animal experimental corroborate the pro-AML effect of p110CUX1. These results provide experimental evidence supporting the involvement of the p110CUX1-PDXP-PI3K/AKT/mTOR axis in AML progression. Hence, targeting p110CUX1 may hold promise as a therapeutic strategy for AML.
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The full-length p200CUX1 protein encoded by the homology frame CUT-like protein (CUX1) plays an important role in tumors as a pro-oncogene or oncogene. However, its role and mechanism in acute myeloid leukemia remain unknown. p200CUX1 regulates several pathways, including the MAPK signaling pathway. Our data showed that p200CUX1 is lowly expressed in THP1 and U937 AML cell lines. Lentiviral overexpression of p200CUX1 reduced proliferation and promoted apoptosis and G0/G1 phase blockade, correlating with MAPK pathway suppression. Additionally, p200CUX1 regulated the expression of bone morphogenetic protein 8B (BMP8B), which is overexpressed in AML. Overexpression of p200CUX1 downregulated BMP8B expression and inhibited the MAPK pathway. Furthermore, BMP8B knockdown inhibited AML cell proliferation, enhanced apoptosis and the sensitivity of ATRA-induced cell differentiation, and blocked G0/G1 transition. Our findings demonstrate the pivotal function of the p200CUX1-BMP8B-MAPK axis in maintaining the viability of AML cells. Consequently, targeting p200CUX1 could represent a viable strategy in AML therapy.
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Apoptosis , Proliferación Celular , Leucemia Mieloide Aguda , Sistema de Señalización de MAP Quinasas , Humanos , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/genética , Sistema de Señalización de MAP Quinasas/fisiología , Línea Celular Tumoral , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo , Proteínas Morfogenéticas Óseas/genética , Progresión de la EnfermedadRESUMEN
BACKGROUND: Gastric cancer (GC) is associated with high mortality rates. Bile acids (BAs) reflux is a well-known risk factor for GC, but the specific mechanism remains unclear. During GC development in both humans and animals, BAs serve as signaling molecules that induce metabolic reprogramming. This confers additional cancer phenotypes, including ferroptosis sensitivity. Ferroptosis is a novel mode of cell death characterized by lipid peroxidation that contributes universally to malignant progression. However, it is not fully defined if BAs can influence GC progression by modulating ferroptosis. AIM: To reveal the mechanism of BAs regulation in ferroptosis of GC cells. METHODS: In this study, we treated GC cells with various stimuli and evaluated the effect of BAs on the sensitivity to ferroptosis. We used gain and loss of function assays to examine the impacts of farnesoid X receptor (FXR) and BTB and CNC homology 1 (BACH1) overexpression and knockdown to obtain further insights into the molecular mechanism involved. RESULTS: Our data suggested that BAs could reverse erastin-induced ferroptosis in GC cells. This effect correlated with increased glutathione (GSH) concentrations, a reduced GSH to oxidized GSH ratio, and higher GSH peroxidase 4 (GPX4) expression levels. Subsequently, we confirmed that BAs exerted these effects by activating FXR, which markedly increased the expression of GSH synthetase and GPX4. Notably, BACH1 was detected as an essential intermediate molecule in the promotion of GSH synthesis by BAs and FXR. Finally, our results suggested that FXR could significantly promote GC cell proliferation, which may be closely related to its anti-ferroptosis effect. CONCLUSION: This study revealed for the first time that BAs could inhibit ferroptosis sensitivity through the FXR-BACH1-GSH-GPX4 axis in GC cells. This work provided new insights into the mechanism associated with BA-mediated promotion of GC and may help identify potential therapeutic targets for GC patients with BAs reflux.
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Ferroptosis , Neoplasias Gástricas , Animales , Humanos , Ácidos y Sales Biliares , Transducción de SeñalRESUMEN
Polylactic acid (PLA) has attracted increasing interest as a sustainable plastic because it can be degraded into CO2 and H2O in nature. However, this process is sluggish, and even worse, it is a CO2-emitting and carbon resource waste process. Therefore, it is highly urgent to develop a novel strategy for recycling post-consumer PLA to achieve a circular plastic economy. Herein, we report a one-pot photoreforming route for the efficient and selective amination of PLA waste into value-added alanine using CoP/CdS catalysts under mild conditions. Results show the alanine production rate can reach up to 2.4â mmol gcat -1 h-1, with a high selectivity (>75 %) and excellent stability. Time-resolved transient absorption spectra (TAS) reveal that CoP can rapidly extract photogenerated electrons from CdS to accelerate proton reduction, favoring hole-dominated PLA oxidation to coproduce alanine. This study offers an appealing way for upcycling PLA waste and creates new opportunities for green synthesis of amino acids.
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BACKGROUND: Dengue is one of the most common diseases in the tropics and subtropics. Whilst mortality is a rare event when adequate supportive care can be provided, a large number of patients get hospitalised with dengue every year that places a heavy burden on local health systems. A better understanding of the support required at the time of hospitalisation is therefore of critical importance for healthcare planning, especially when resources are limited during major outbreaks. METHODS: Here we performed a retrospective analysis of clinical data from over 1500 individuals hospitalised with dengue in Vietnam between 2017 and 2019. Using a broad panel of potential biomarkers, we sought to evaluate robust predictors of prolonged hospitalisation periods. RESULTS: Our analyses revealed a lead-time bias, whereby early admission to hospital correlates with longer hospital stays - irrespective of disease severity. Importantly, taking into account the symptom duration prior to hospitalisation significantly affects observed associations between hospitalisation length and previously reported risk markers of prolonged stays, which themselves showed marked inter-annual variations. Once corrected for symptom duration, age, temperature at admission and elevated neutrophil-to-lymphocyte ratio were found predictive of longer hospitalisation periods. CONCLUSION: This study demonstrates that the time since dengue symptom onset is one of the most significant predictors for the length of hospital stays, independent of the assigned severity score. Pre-hospital symptom durations need to be accounted for to evaluate clinically relevant biomarkers of dengue hospitalisation trajectories.
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Dengue Grave , Humanos , Dengue Grave/diagnóstico , Dengue Grave/epidemiología , Estudios Retrospectivos , Hospitalización , Tiempo de Internación , BiomarcadoresRESUMEN
Machine vision has been used to grade the potted anthurium plant in large-scale production recently. Images are taken to measure the number and size of anthurium spathes. However, due to the limitation of the shooting angle, the occlusion problem reduces the accuracy of measurement. It is necessary to segment the overlapping spathes and repair the incomplete ones. The traditional image completion model has good performance on missing small areas, but it is not satisfactory for missing large areas. In this article, a multi-scale fusion Recurrent Feature Reasoning (RFR) network was proposed to repair the spathe images. Unlike the traditional RFR, a multi-layer component was used in the feature reasoning module. This network can combine multi-scale features to complete the learning task and obtain more details of the spathe, which makes the network more advantageous in image completion when missing large areas of spathes. In this study, a comparison experiment between this network and the widely used image completion network was performed, and the results showed that this network performed well in all types of image completion, especially with large-area incomplete images.
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Photocatalysis has gained significant attention and interest as an environmentally friendly and sustainable approach to the production of hydrogen through water splitting and the reduction and conversion of CO2. Copper tungstate (CuWO4) is a highly promising candidate for these applications owing to its appropriate bandgap and superior stability under different conditions. However, the redox behavior of the CuWO4 surfaces under different environments and their impact on the morphology of the material nanoparticles, as well as the electronic properties, remain poorly understood. In this study, we have employed density functional theory calculations to investigate the properties of the bulk and pristine surfaces of CuWO4 and how the latter are impacted by oxygen chemisorption under the conditions required for photocatalytic water splitting and carbon dioxide reduction processes. We have calculated the lattice parameters and electronic properties of the bulk phase, as well as the surface energies of all possible nonpolar, stoichiometric, and symmetric terminations of the seven low-Miller index surfaces and found that the (010) and (110) facets are the thermodynamically most stable. The surface-phase diagrams were used to derive the equilibrium crystal morphologies, which show that the pristine (010) surface is prominent under synthesis and room conditions. Our crystal morphologies suggest that the partially oxidized (110) surface and the partially reduced (011) surface may play an important role in the photocatalytic splitting of water and CO2 conversion, respectively. Our results provide a comprehensive understanding of the CuWO4 surfaces under the conditions of important photocatalytic applications.
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Cytarabine-resistant acute myeloid leukemia (AML) is a common phenomenon, necessitating the search for new chemotherapeutics. WEE1 participates in cell cycle checkpoint signaling and inhibitors targeting WEE1 (WEE1i) constitute a potential novel strategy for AML treatment. HDAC (histone deacetylase) inhibitors have been shown to enhance the anti-tumor effects of WEE1i but molecular mechanisms of HDAC remain poorly characterized. In this study, the WEE1 inhibitor PD0166285 showed a relatively good anti-leukemia effect. Notably, PD0166285 can arise the expression of HDAC11 which was negatively correlated with survival of AML patients. Moreover, HDAC11 can reduced the anti-tumor effect of PD0166285 through an effect on p53 stability and the changes in phosphorylation levels of MAPK pathways. Overall, the cell cycle inhibitor, PD0166285, is a potential chemotherapeutic drug for AML. These fundings contribute to a functional understanding of HDAC11 in AML.
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Proteínas de Ciclo Celular , Leucemia Mieloide Aguda , Humanos , Proteínas de Ciclo Celular/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Ubiquitina/metabolismo , Ubiquitina/farmacología , Ubiquitina/uso terapéutico , Proteínas Nucleares/metabolismo , Leucemia Mieloide Aguda/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Inhibidores de Histona Desacetilasas/uso terapéutico , Histona Desacetilasas/metabolismo , Apoptosis , Línea Celular TumoralRESUMEN
Introduction: Anthracnose of banana caused by Colletotrichum species is one of the most serious post-harvest diseases, which can cause significant yield losses. Clarifying the infection mechanism of the fungi using non-destructive methods is crucial for timely discriminating infected bananas and taking preventive and control measures. Methods: This study presented an approach for tracking growth and identifying different infection stages of the C. musae in bananas using Vis/NIR spectroscopy. A total of 330 banana reflectance spectra were collected over ten consecutive days after inoculation, with a sampling rate of 24 h. The four-class and five-class discriminant patterns were designed to examine the capability of NIR spectra in discriminating bananas infected at different levels (control, acceptable, moldy, and highly moldy), and different time at early stage (control and days 1-4). Three traditional feature extraction methods, i.e. PC loading coefficient (PCA), competitive adaptive reweighted sampling (CARS) and successive projections algorithm (SPA), combining with two machine learning methods, i.e. partial least squares discriminant analysis (PLSDA) and support vector machine (SVM), were employed to build discriminant models. One-dimensional convolutional neural network (1D-CNN) without manually extracted feature parameters was also introduced for comparison. Results: The PCA-SVM and·SPA-SVM models had good performance with identification accuracies of 93.98% and 91.57%, 94.47% and 89.47% in validation sets for the four- and five-class patterns, respectively. While the 1D-CNN models performed the best, achieving an accuracy of 95.18% and 97.37% for identifying infected bananas at different levels and time, respectively. Discussion: These results indicate the feasibility of identifying banana fruit infected with C. musae using Vis/NIR spectra, and the resolution can be accurate to one day.
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BACKGROUND: miR-454-3p is considered to have a crucial role in cancer progression, but the potential involvement in acute myeloid leukemia (AML) remains unclear. METHODS: Expression of miR-454-3p and ZEB2 mRNA and protein were quantified in AML cell lines. Cells were transfected with miR-454-3p inhibitor or mimic and cell growth was assessed by colony formation and CCK-8 assays and the cell cycle, apoptosis and autophagy were investigated by Western blotting, flow cytometry, immunofluorescence and 3-methyladenine (3-MA) treatment. RESULTS: miR-454-3p expression was attenuated in AML cells. miR-454-3p overexpression attenuated cell growth and stimulated cell cycle arrest, apoptosis and autophagy. Dual-luciferase reporter assays and bioinformatics analysis showed that AML progression was inhibited when miR-454-3p regulated ZEB2, an effect confirmed by rescue assays. 3-MA reduced the autophagy-inducing effect of ZEB2 knockdown and indicated that autophagy induced apoptosis. miR-454-3p downregulated p-mTOR/p-AKT levels in AML cells. CONCLUSION: The novel role of miR-454-3p as a tumor inhibitor in AML via regulation of the ZEB2/AKT/mTOR axis was demonstrated, indicating miR-454-3p as a potential new molecular target for AML.
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Leucemia Mieloide Aguda , MicroARNs , Humanos , Proteínas Proto-Oncogénicas c-akt , Apoptosis , Autofagia/genética , Leucemia Mieloide Aguda/genética , Serina-Treonina Quinasas TOR , MicroARNs/genética , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc/genéticaRESUMEN
Acute myeloid leukemia (AML) is a malignancy of the hematological system, for which there remains an urgent need for new therapeutic and diagnostic targets. COMM domain containing 7 (COMMD7) is a recently-identified oncogene linked to poor prognosis in AML. COMMD7 regulates multiple signaling pathways, including nuclear factor-kappa B (NF-κB) signaling. Here, we report that COMMD7 is highly expressed in the AML cell lines KG1a and U937 and that its inhibition by shRNA reduced proliferation, promoted apoptosis and facilitated cell cycle arrest in the G2/M phase in relation to depression of the NF-κB pathway. Furthermore, zinc finger protein 460 (ZNF460) is overexpressed in AML and regulates COMMD7. We found that knockdown of ZNF460 downregulated the expression of COMMD7 while the NF-κB pathway was also inhibited. In addition, we noticed that knockdown of ZNF460 reduced proliferation and increased apoptosis rate of AML cells and that the cell cycle was blocked in the G2/M phase. In brief, our results revealed a critical effect of the ZNF460-COMMD7-NF-κB axis for the proliferation of AML cells. Therefore, COMMD7 may be a possible therapeutic target for AML.
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Leucemia Mieloide Aguda , FN-kappa B , Humanos , FN-kappa B/genética , FN-kappa B/metabolismo , Transducción de Señal/genética , Leucemia Mieloide Aguda/metabolismo , Ciclo Celular , Proliferación Celular/genética , Proteínas de Unión al ADN/metabolismo , Factores de Transcripción/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismoRESUMEN
Preliminary researches have confirmed that the number of apoptosis of adipose tissue-derived stem cells (ADSCs) in patients with diabetes is significantly increased, leading to a difficult healing wound. Increasing researches revealed that circular RNAs (circRNAs) can control apoptosis. However, it is still unclear whether and how circRNAs are critical for regulating ADSCs apoptosis. In this study, we utilized in vitro model in which ADSCs were cultivated with normal glucose (NG) (5.5 mM) or high glucose (HG) (25 mM) medium, respectively, and found that more apoptotic ADSCs were observed in HG medium comparing to ADSCs in NG medium. Furthermore, we found that hsa_circ_0008500 attenuated HG-mediated ADSCs apoptosis. In addition, Hsa_circ_0008500 could directly interact with hsa-miR-1273h-5p, acting as a miRNA sponge, which subsequently suppressed Ets-like protein-1(ELK1) expression, the downstream target of hsa-miR-1273h-5p. Thus, these results indicated that targeting the hsa_circ_0008500/hsa-miR-1273h-5p/ELK1 signaling pathway in ADSCs may be a potential target for repairing diabetic wounds.
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MicroARNs , ARN Circular , Humanos , ARN Circular/genética , ARN Circular/metabolismo , Línea Celular Tumoral , MicroARNs/genética , MicroARNs/metabolismo , Células Madre , Apoptosis/genética , Glucosa/farmacología , Proliferación Celular/genética , Proteína Elk-1 con Dominio etsRESUMEN
BACKGROUND: Polo-like kinase 4 (PLK4) is a crucial regulator for centriole replication and is reported to be aberrantly expressed in various cancers, where it participates to tumorigenesis. However, PLK4 effect in acute myeloid leukemia (AML), is still uncertain. This study investigates the function of PLK4 in AML. METHODS: Quantitative real-time PCR was used to measure the level of PLK4. Centrinone, a selective PLK4 small molecule inhibitor, was used for PLK4 inhibition and explore its effect in AML cells. The cell growth was detected by the CCK8, while the cell cycle and apoptosis were assessed by flow cytometry. The level of proteins associated with apoptosis, cell cycle and endoplasmic reticulum (ER) stress were analyzed by western blotting. RESULTS: PLK4 was overexpressed in AML cells. PLK4 knockdown or its specific inhibition by centrinone induced G2/M phase arrest via suppressing the expression of cyclin B1 and Cdc2 and promoting the level of proapoptotic proteins. Moreover, PLK4 targeting enhanced the level of proteins related to ER stress, such as GRP78, ATF4, ATF6, and CHOP. CONCLUSION: These findings demonstrated that targeting PLK4 can induce apoptosis, G2/M and ER stress in AML cells.
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Apoptosis , Leucemia Mieloide Aguda , Humanos , Regulación hacia Abajo , Línea Celular Tumoral , Puntos de Control de la Fase G2 del Ciclo Celular , Leucemia Mieloide Aguda/genética , Proteínas Serina-Treonina Quinasas/genéticaRESUMEN
BACKGROUND: Studies have confirmed that acute myeloid leukemia (AML) cells with DNA methyltransferase 3A Arg882His (DNMT3A R882H) mutation show an increased proliferation capability. However, the associated mechanism is still unclear. Glycolysis is involved in regulating malignant proliferation of cancer cell. Hence, we analyzed whether the DNMT3A R882H mutation interferes with glycolysis and thereby influences AML cell proliferation. METHODS: We generated AML cell line carrying a DNMT3A-R882H mutation and compared it with the wild type (DNMT3A-WT) with regard to glycolysis regulation. Moreover, we analyzed the cell line's proliferation and apoptosis by a CCK-8 assay, western blotting, and flow cytometry. The role of NRF2/NQO1 signaling in regulating glycolysis was investigated by NRF2-knockdown and Brusatol (specific inhibitor of NRF2) treatment. RESULTS: DNMT3A R882H cells had a higher glucose transport capacity compared to WT cells and their viability could be reduced by glucose deprivation. Moreover, daunorubicin had a slight inhibitory effect on glycolysis while glycolysis inhibition re-sensitized mutant cells to daunorubicin. Obviously, DNMT3A R882H mutation activated the NRF2/NQO1 pathway and enhanced the glycolytic activity in mutant cells. CONCLUSION: Taken together, these results suggest a novel mechanism by which a DNMT3A R882H mutation promotes glycolysis via activation of NRF2/NQO1 pathway. A parallel glycolysis inhibition adds to the anticancer effects of daunorubicin which might lead to a novel therapeutic approach for the treatment of AML patients carrying a DNMT3A R882H mutation.
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ADN Metiltransferasa 3A , Leucemia Mieloide Aguda , Humanos , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Supervivencia Celular , Metilación de ADN , Mutación/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Daunorrubicina/farmacología , NAD(P)H Deshidrogenasa (Quinona)/genética , NAD(P)H Deshidrogenasa (Quinona)/metabolismoRESUMEN
Members of glycosyltransferase family 75 (GT75) not only reversibly catalyze the autoglycosylation of a conserved arginine residue with specific NDP-sugars but also exhibit NDP-pyranose mutase activity that reversibly converts specific NDP-pyranose to NDP-furanose. The latter activity provides valuable NDP-furanosyl donors for glycosyltransferases and requires a divalent cation as a cofactor instead of FAD used by UDP-D-galactopyranose mutase. However, details of the mechanism for NDP-pyranose mutase activity are not clear. Here we report the first crystal structures of GT75 family NDP-pyranose mutases. The novel structures of GT75 member MtdL in complex with Mn2+ and GDP, GDP-D-glucopyranose, GDP-L-fucopyranose, GDP-L-fucofuranose, respectively, combined with site-directed mutagenesis studies, reveal key residues involved in Mn2+ coordination, substrate binding, and catalytic reactions. We also provide a possible catalytic mechanism for this unique type of NDP-pyranose mutase. Taken together, our results highlight key elements of an enzyme family important for furanose biosynthesis.
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Actinobacteria , Glicosiltransferasas , Transferasas Intramoleculares , Galactosa/metabolismo , Glicosiltransferasas/química , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Transferasas Intramoleculares/química , Transferasas Intramoleculares/genética , Transferasas Intramoleculares/metabolismo , Mutagénesis Sitio-Dirigida , Actinobacteria/enzimologíaRESUMEN
Mycotoxins have substantial impacts on agricultural production and food preservation. Some have high similarities in bioactivity but subtle differences on structures from various fungal producers. Understanding of their complex cross-biosynthesis will provide new insights into enzyme functions and food safety. Here, based on structurally related mycotoxins, such as aurovertins, asteltoxin, and citreoviridin, we showed that methyltransferase (MT)-catalyzed methylation is required for efficient oxidation and polyketide stability. MTs have broad interactions with polyketide synthases and flavin-containing monooxygenases (FMOs), while MT AstB is required for FMO AstC functionality in vivo. FMOs have common catalysis on pyrone-polyene intermediates but different catalytic specificity and efficiency on oxidative intermediates for the selective production of more toxic and complex mycotoxins. Thus, the subtle protein interaction and elaborate versatile catalysis of biosynthetic enzymes contribute to the efficient and selective biosynthesis of these structure-related mycotoxins and provide the basis to re-evaluate and control mycotoxins for agricultural and food safety.
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Micotoxinas , Policétidos , Micotoxinas/química , Policétidos/metabolismo , Metiltransferasas , Sintasas Poliquetidas/metabolismo , CatálisisRESUMEN
Efficient biosynthesis of microbial bioactive natural products (NPs) is beneficial for the survival of producers, while self-protection is necessary to avoid self-harm resulting from over-accumulation of NPs. The underlying mechanisms for the effective but tolerable production of bioactive NPs are not well understood. Herein, in the biosynthesis of two fungal polyketide mycotoxins aurovertinâ E (1) and asteltoxin, we show that the cyclases in the gene clusters promote the release of the polyketide backbone, and reveal that a signal peptide is crucial for their subcellular localization and full activity. Meanwhile, the fungus adopts enzymatic acetylation as the major detoxification pathway of 1. If intermediates are over-produced, the non-enzymatic shunt pathways work as salvage pathways to avoid excessive accumulation of the toxic metabolites for self-protection. These findings provided new insight into the interplay of efficient backbone release and multiple detoxification strategies for the production of fungal bioactive NPs.
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Micotoxinas , Policétidos , Policétidos/metabolismo , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Procesamiento Proteico-Postraduccional , Familia de MultigenesRESUMEN
Purpose: This study aimed to clarify the formation and fixation of the annulus of Zinn (AZ) and its relationship with the extraocular muscles by using ultrathin plastination and three-dimensional models. Methods: Eighteen cadaveric heads (36 sides of the orbital apex) were plastinated to coronal (16 sides), sagittal (13 sides), and horizontal (5 sides) ultrathin plastination sections to be investigated at both macroscopic and microscopic levels. One cadaveric head was used for endoscopic dissection to identify anatomic landmarks. Results: There were two fibrous triangles adhered to both ends of the anterior surface of the optic strut. The superior rectus muscle originated from the superior fibrous triangle, and the lateral, inferior, and medial rectus muscles emerged from the inferior fibrous triangle. It was not until 5.46 ± 0.41 mm anterior to the optic strut that the complete tendinous ring composed of rectus muscles, optic nerve sheath, and periosteum was formed. The superior oblique and levator palpebrae superioris muscles originated from the medial fibrous band of the AZ. At the posterior of the AZ, there was a potential passage between the medial rectus muscle and the optic nerve. Conclusions: The fixation of the AZ was composed of the connection of the annular tendon to the optic strut posteriorly and the attachment of the complete tendinous ring to the lesser and greater wings of the sphenoid bone anteriorly. The triangular route area between the optic nerve and medial rectus muscle was located on the anterior side of the base of the optic strut.
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Músculos Oculomotores , Plastinación , Humanos , Músculos Oculomotores/cirugía , Músculos Oculomotores/patología , Tendones , Nervio Óptico , CadáverRESUMEN
Knowledge of the clinical presentation of central nervous system (CNS) infections and the causative pathogens is crucial for appropriate diagnosis and rapid initiation of appropriate treatment to prevent severe neurological sequelae. The aim of this study is to understand the aetiology of CNS infections based on the clinical presentation of Vietnamese patients. A prospective hospital-based cohort study was conducted between May 2014 and May 2017. We screened 137 patients with clinically suspected CNS infection for fungal, bacterial and viral pathogens using their cerebrospinal fluid (CSF) and blood cultures. In addition, DNA or RNA extracted from CSF samples were subjected to nucleic acid testing (NAT) with a selective panel of bacterial, viral and fungal pathogens. At least one pathogen could be detected in 41% (n = 56) of the patients. The main pathogens causing CNS infections were Streptococcus suis (n = 16; 12%) and Neisseria meningitidis (n = 9; 7%), followed by Herpes simplex virus 1/2 (n = 4; 3%) and Klebsiella pneumoniae (n = 4; 3%). Other pathogens were only identified in a few cases. Patients with bacterial CNS infections were significantly older, had a worse outcome, a lower Glasgow Coma Scale (GCS), a higher rate of speech impairment and neck stiffness than patients with viral or tuberculous CNS infections. In northern Vietnam, adults are mostly affected by bacterial CNS infections, which have a severe clinical course and worse outcomes compared to viral or tuberculous CNS infections. Clinicians should be aware of the regional occurrence of pathogens to initiate rapid and appropriate diagnosis and treatment.