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1.
Sci Total Environ ; 922: 171357, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38431167

RESUMEN

Nitrous oxide (N2O) represents a significant environmental challenge as a harmful, long-lived greenhouse gas that contributes to the depletion of stratospheric ozone and exacerbates global anthropogenic greenhouse warming. Composting is considered a promising and economically feasible strategy for the treatment of organic waste. However, recent research indicates that composting is a source of N2O, contributing to atmospheric pollution and greenhouse effect. Consequently, there is a need for the development of effective, cost-efficient methodologies to quantify N2O emissions accurately. In this study, we employed the model-agnostic meta-learning (MAML) method to improve the performance of N2O emissions prediction during manure composting. The highest R2 and lowest root mean squared error (RMSE) values achieved were 0.939 and 18.42 mg d-1, respectively. Five machine learning methods including the backpropagation neural network, extreme learning machine, integrated machine learning method based on ELM and random forest, gradient boosting decision tree, and extreme gradient boosting were adopted for comparison to further demonstrate the effectiveness of the MAML prediction model. Feature analysis showed that moisture content of structure material and ammonium concentration during composting process were the two most significant features affecting N2O emissions. This study serves as proof of the application of MAML during N2O emissions prediction, further giving new insights into the effects of manure material properties and composting process data on N2O emissions. This approach helps determining the strategies for mitigating N2O emissions.

2.
Front Cell Dev Biol ; 12: 1383200, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505258

RESUMEN

Polycomb group (PcG) proteins are a subset of epigenetic factors that are highly conserved throughout evolution. In mammals, PcG proteins can be classified into two muti-proteins complexes: Polycomb repressive complex 1 (PRC1) and PRC2. Increasing evidence has demonstrated that PcG complexes play critical roles in the regulation of gene expression, genomic imprinting, chromosome X-inactivation, and chromatin structure. Accordingly, the dysfunction of PcG proteins is tightly orchestrated with abnormal developmental processes. Here, we summarized and discussed the current knowledge of the biochemical and molecular functions of PcG complexes, especially the PRC1 and PRC2 in mammalian development including embryonic development and tissue development, which will shed further light on the deep understanding of the basic knowledge of PcGs and their functions for reproductive health and developmental disorders.

3.
Molecules ; 28(24)2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38138582

RESUMEN

As an important component of N-linked glycoproteins, the core pentasaccharide is highly crucial to the potential application prospect of glycoprotein. However, the gas phase conformation study is a challenging one due to the size and complexity of the molecule, together with the necessity to rely on quantum chemistry modeling for relevant energetics and structures. In this paper, the structures of the trisaccharides and core pentasaccharides in N-linked glycans in the gas phase were constructed by a three-step tree-based (TSTB) sampling. Since single point energies of all the conformers are calculated at the temperature of zero, it is necessary to evaluate the stability at a high temperature. We calculate the Gibbs free energies using the standard thermochemistry model (T = 298.15 K). For trimannose, the energetic ordering at 298.15 K can be strongly changed compared to 0 K. Moreover, two structures of trimannose with high energies at 0 K are considered to provide a much better match of IR vibration signatures with the low Gibbs free energies. On this basis, the core pentasaccharide was constructed in three ways. The building configurations of core pentasaccharide were optimized to obtain reasonable low-energy stable conformers. Fortunately, the lowest-energy structure of core pentasaccharide is eventually the minimum at 0 K and 298.15 K. Furthermore, spectrum analysis of core pentasaccharide was carried out. Although poorly resolved, its contour from the experiment was in qualitative correspondence with the computed IR spectrum associated with its minimum free energy structure. A large number of strongly and weakly hydrogen-bonded hydroxyl and acetylamino groups contribute to a highly congested set of overlapping bands. Compared with traditional conformation generators, the TSTB sampling is employed to efficiently and comprehensively obtain preferred conformers of larger saccharides with lower energy.

4.
Entropy (Basel) ; 25(10)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37895526

RESUMEN

In this paper, we propose a pre-configured error pattern ordered statistics decoding (PEPOSD) algorithm and discuss its application to short cyclic redundancy check (CRC)-polar codes. Unlike the traditional OSD that changes the most reliable independent symbols, we regard the decoding process as testing the error patterns, like guessing random additive noise decoding (GRAND). Also, the pre-configurator referred from ordered reliability bits (ORB) GRAND can better control the range and testing order of EPs. An offline-online structure can accelerate the decoding process. Additionally, we also introduce two orders to optimize the search order for testing EPs. Compared with CRC-aided OSD and list decoding, PEPOSD can achieve a better trade-off between accuracy and complexity.

5.
Oncotarget ; 13: 863, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35813282

RESUMEN

[This retracts the article DOI: 10.18632/oncotarget.21069.].

6.
Nutrients ; 14(7)2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35406031

RESUMEN

This study measured the total potentially available nucleoside (TPAN) content in breast milk from six different regions of China as a part of the Maternal Nutrition and Infant Investigation (MUAI) study. A total of 631 breast milk samples were collected from healthy, lactating women with singleton, full-term pregnancies between 40 and 45 days postpartum in Changchun, Chengdu, Lanzhou, Shanghai, Tianjin, and Guangzhou. TPAN and free 5'-monophosphate nucleotide (5'-MNT) contents were determined by high-performance liquid chromatography. The TPAN content of the Chinese mature milk ranged from 11.61 mg/L to 111.09 mg/L, with a median level of 43.26 mg/L. Four types of nucleotides were identified, and the median levels of cytidine monophosphate (CMP), uridine monophosphate (UMP), guanosine monophosphate (GMP), and adenosine monophosphate (AMP) were 22.84 mg/L, 9.37 mg/L, 4.86 mg/L, and 4.80 mg/L, respectively. CMP was the predominant nucleotide, accounting for 52.9% of the TPAN content, while free 5'-MNT accounted for 18.38% of the TPAN content. The distribution pattern of the TPAN content and level of the individual nucleotides were significantly different among the selected regions (p < 0.05), but the result showed no significant differences in the TPAN level in breast milk (p > 0.05). In addition, no correlation was reported between the geographic distribution and TPAN levels. This result showed that TPAN better reflects the level of total potential nucleosides in Chinese breast milk rather than 5'-MNT in free form. CMP, UMP, GMP, and AMP are the only 4 types of nucleotides reported in all detections. In addition, results revealed a large variation of TPAN levels in Chinese breast milk across six regions, so that the median value may not be the optimal fortification level of TPAN for Chinese infant populations.


Asunto(s)
Leche Humana , Nucleótidos , Adenosina Monofosfato , China , Citidina Monofosfato/análisis , Femenino , Humanos , Lactante , Lactancia , Leche Humana/química , Nucleósidos , Uridina Monofosfato/análisis
7.
Hum Exp Toxicol ; 40(3): 439-451, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32909851

RESUMEN

The pathogenesis of preeclampsia (PE) is complicated and multiple risk factors have been associated with its occurrence. Still, the underlying molecular mechanisms involved in PE remain elusive. Aberrant apoptosis and insufficient invasion of trophoblasts have been observed and are considered vital pathological features in PE. Herein, we found that miR-155 can specifically degrade the mRNA of the Hedgehog ligand sonic hedgehog (SHH), using dual luciferase reporter assays. Quantitative real-time PCR found that administering miR-155 mimics or inhibitors could significantly decrease or increase the expression of SHH in the trophoblasts, respectively. The transcription levels of miR-155 in the placenta were higher in patients with PE compared to the levels in healthy pregnant women, as shown by quantitative real-time PCR. Serum levels of miR-155 could predict the diagnosis of PE by receiver operating characteristic curve analysis and diagnosis evaluation tests. A significant increase in apoptosis was observed after administering miR-155 in HTR8/SVneo cells cultured ex vivo, accompanied by reduced proliferation. Mechanistically, transcriptional activity and expression of GLi1 were also inhibited under treatment of miR-155, and could be recovered after supplying additional recombinant human SHH to primary trophoblasts from patients, as determined by luciferase activity assays and western blotting. We further found that inhibiting miR-155 increased the production of SHH and improved the phenotype in primary trophoblasts from patients with PE. Our data show that miR-155 regulates apoptosis of trophoblasts in PE, which has potential value for predicting PE risk and might be deemed as a therapeutic target for treating PE.


Asunto(s)
Apoptosis , MicroARNs , Preeclampsia/genética , Trofoblastos , Células Cultivadas , Femenino , Proteínas Hedgehog/sangre , Proteínas Hedgehog/genética , Humanos , Proteínas Nucleares/genética , Placenta , Preeclampsia/sangre , Embarazo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Regulación hacia Arriba , Proteína con Dedos de Zinc GLI1/genética , Proteína Gli2 con Dedos de Zinc/genética
8.
Mol Ther Nucleic Acids ; 22: 38-49, 2020 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-32911343

RESUMEN

Emerging studies indicate that long noncoding RNAs (lncRNAs) play crucial roles in ovarian cancer (OC). By analyzing high-throughput data, we found that SNHG17 was highly expressed in multiple OC cohorts. However, its functions in OC were not explored. In this study, lncRNA expression in OC was analyzed by a series of microarray data. The functions of SNHG17 were investigated by various in vitro and in vivo assays. Fluorescence in situ hybridization (FISH), RNA pull-down, chromatin immunoprecipitation (ChIP), RNA immunoprecipitation (RIP), and luciferase reporter assays were used to reveal the potential mechanisms involved in the effects of SNHG17. We found that SNHG17 was overexpressed in OC and that the oncogenic transcription factor STAT3 was involved in promoting its expression. In addition, high SNHG17 expression was associated with a poor prognosis in OC. Functional analysis revealed that SNHG17 could promote OC cell growth. Mechanistically, SNHG17 was found to be located predominantly in the cytoplasm. It could regulate expression of CDK6, an important cell-cycle regulator, by acting as a molecular sponge for miR-214-3p. In summary, our study suggested that SNHG17 acted as an oncogene in OC, which might serve as a novel target for OC diagnosis and therapy.

9.
Carbohydr Res ; 496: 108114, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32823055

RESUMEN

The interaction between sugars and water molecules plays a crucial role in exploring the complex metabolic reactions of living systems. The fully random conformational search is employed to investigate the first hydration shell structure of glucose. The circumference of glucose is divided into three hydrate sites according to the location of water molecules. Especially, four water molecules can saturate hydrate site AI and while more water molecules will be required to saturate hydrate sites AIII and AII. Moreover, the hydration energies of water molecules at different hydration region indicate that the competition of the three hydrate sites for water molecules changes dynamically with the increase of water molecules. In addition, we calculate the Raman spectra of the hydrated glucose, which are in good agreement with the experimental and theoretical Raman spectra of the glucose solution.


Asunto(s)
Glucosa/química , Teoría Cuántica , Agua/química , Conformación de Carbohidratos , Simulación de Dinámica Molecular , Espectrometría Raman
10.
Medicine (Baltimore) ; 99(28): e21198, 2020 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-32664166

RESUMEN

INTRODUCTION: Kasabach-Merritt Syndrome (KMS) is an extremely rare disease in adults, which lead to consumptive coagulopathy characterized by severe hypofibrinogenemia and thrombocytopenia. PATIENT CONCERNS:: a 25-year-old Chinese pregnant women complicated by preeclampsia and KMS presented with refractory postpartum hemorrhage and incision bleeding after cesarean section. DIAGNOSIS: The diagnosis of KMS was made based on clinical manifestation of Kaposiform Hemangioendothelioma, severe hypofibrinogenemia and thrombocytopenia. INTERVENTIONS: After a poor response to massive blood products transfusion for 1 week, corticosteroid treatment was initiated for 3 days. OUTCOMES: The patient reached a normal platelet count and a mild anemia within 4 weeks. Two months later, all laboratory values had returned to normal, and the incision was healing well. CONCLUSION: Pregnancy complicated by preeclampsia and surgery may have contributions for the development of Kasabach-Merritt syndrome. Corticosteroid is indicated in the episode of acute Kasabach-Merritt syndrome after the failure of massive blood transfusion.


Asunto(s)
Corticoesteroides/uso terapéutico , Síndrome de Kasabach-Merritt/terapia , Hemorragia Posparto/tratamiento farmacológico , Preeclampsia/terapia , Complicaciones Hematológicas del Embarazo/terapia , Adulto , Cesárea , Femenino , Humanos , Síndrome de Kasabach-Merritt/complicaciones , Hemorragia Posparto/etiología , Preeclampsia/etiología , Embarazo , Complicaciones Hematológicas del Embarazo/etiología
11.
J Biomater Appl ; 35(2): 149-157, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32390570

RESUMEN

Nanodrug delivery systems have been widely researched to achieve efficient antitumor drug delivery. However, the controlled drug delivery at tumor cells remains the main challenge for antitumor therapy. Herein, a pH and reduction-responsive nanocarrier based on green tea polyphenols was employed as a smart excipient for chemotherapy drug delivery. Paclitaxel, as a chemotherapy drug, was loaded in the nanocarrier, noted as green tea polyphenol/paclitaxel. The green tea polyphenol/paclitaxel kept constant diameter at physiological condition (i.e. pH 7.4), while gradually enlarged at acid environment (pH = 5.5) and the reductive environment. The in vitro paclitaxel release results indicated that the release of paclitaxel from the green tea polyphenol/paclitaxel at pH 7.4 was slow, whereas obviously accelerated at the acid environment (pH = 5.5) and the reductive environment. The in vitro antitumor assay showed more efficient tumor cells inhibition of green tea polyphenol/paclitaxel than free paclitaxel. Meanwhile, due to the proper size (∼100 nm), green tea polyphenol/paclitaxel could effectively accumulate at tumor sites. In the in vivo mice bearing A549 xenograft mouse models, green tea polyphenol/paclitaxel exhibited satisfactory antitumor effect and depressed system toxicity when compared with free paclitaxel, owing to the enhanced paclitaxel accumulation and controlled paclitaxel release in the tumor cells. With simple compositions and satisfactory antitumor effects, this green tea polyphenol-based nanocarrier can be a promising nanodrug delivery system for the therapy of cancers.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Preparaciones de Acción Retardada/química , Paclitaxel/administración & dosificación , Polifenoles/química , Té/química , Células A549 , Animales , Antineoplásicos Fitogénicos/uso terapéutico , Sistemas de Liberación de Medicamentos , Humanos , Concentración de Iones de Hidrógeno , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Nanocápsulas/química , Paclitaxel/uso terapéutico
13.
World Neurosurg ; 138: 645-653, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31931232

RESUMEN

BACKGROUND: The article uses ultrasound imaging standard section to examine the fetal central nervous system (CNS) in early pregnancy, combined with ultrasound imaging in the diagnosis of fetal CNS malformation in the middle and late pregnancy, to determine the feasibility of ultrasound imaging in the detection of CNS abnormalities in the first trimester of the fetus. METHODS: The article selected 2701 pregnant women from the Department of Ultrasound in our hospital from November 2012 to November 2016 to screen for the transparent layer of the fetal neck in early pregnancy, with a total of 2751 cases. The article uses Madison V20 and Madison XG color Doppler ultrasound diagnostic instruments, the probe frequency is measured from 2.0-3.5 MHz, grouped according to gestational age, the statistical section of the case is displayed, and the transparent layer of the neck value is used to count the ultrasound image during early pregnancy. The detection of the CNS malformation by the standard section examination and the sensitivity, specificity, positive predictive value, and negative predictive value of the diagnosis may affect the cause of the CNS display rate. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of the ultrasound standard section in the diagnosis of fetal CNS malformation in early pregnancy were 85.7%, 100%, 100%, and 99.9%, respectively. Through research, it is found that the use of ultrasound imaging standard section can effectively diagnose fetal CNS severe deformity in early pregnancy, and the detection rate of CNS malformation in early pregnancy is 85.7%. At the same time, the number of positive cases and CNS malformations in this group were few. CONCLUSIONS: The positive cases detected in early pregnancy were severe malformations of the CNS. The diagnosis of other CNS malformations in the fetus needs further study.


Asunto(s)
Feto/diagnóstico por imagen , Malformaciones del Sistema Nervioso/diagnóstico por imagen , Obstetricia/métodos , Ultrasonografía Doppler en Color/métodos , Ultrasonografía Prenatal/métodos , Femenino , Feto/anomalías , Estudios de Seguimiento , Humanos , Malformaciones del Sistema Nervioso/embriología , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo
14.
Cell Biosci ; 9: 86, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31649814

RESUMEN

Pregnancy-associated cardiomyopathy (PAH) represents a pregnancy-associated myocardial disease that is characterized by the progression of heart failure due to marked left ventricular systolic dysfunction. Compelling evidence has highlighted the potential of angiotensin (Ang) receptor inhibitors as therapeutic targets in PAH treatment. The present study aims to elucidate the molecular mechanisms underlying Ang II receptor inhibitor LCZ696 treatment in PAH. Initially, a PAH mouse model was induced, followed by intraperitoneal injection of LCZ696. Subsequently, cardiomyocytes and fibroblasts were isolated, cultured, and treated with Ang II and LCZ696, followed by detection of the total survival rate, cardiac injury, cardiac fibrosis and apoptosis. Moreover, in order to quantify the cardiac hypertrophy and fibrosis degree of cardiac fibroblasts, the expression levels of markers of cardiac hypertrophy (ANP, ßMHC and TIMP2) and markers of fibrosis (collagen I, collagen III and TGF-ß) were evaluated. Furthermore, the potential effect of LCZ696 on the extracellular signal-regulated kinase (ERK) signaling pathway was examined. The acquired findings revealed that LCZ696 increased the total survival rate of PAH mice, but decreased cardiac injury, cardiac fibrosis, and apoptosis in vitro. LCZ696 attenuated cardiac injury induced by Ang II through the inhibition the expression of markers of cardiac hypertrophy, fibrosis and apoptosis by inhibiting ERK phosphorylation in vivo and in vitro. Altogether, LCZ676 could potentially alleviate cardiac remodeling in mice with PAH via blockade of the ERK signaling pathway activation. Our findings suggest that LCZ696 could be a potential target for PAH therapy.

15.
Int J Biol Macromol ; 125: 941-947, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30572042

RESUMEN

Modification of natural polysaccharides such as chitosan (CS), ß­cyclodextrin (ß-CD), and alginic acid offers a promising strategy for the preparation of smart drug carriers, and latest innovations on such carriers are focused on stimuli-responsive biomaterials. In this study, highly hydrophilic three-demensional (3D) porous CS-grafted ß-CD (CS-g-ß-CD) was prepared through the Williamson ether synthesis reaction with epichlorohydrin (ECH) as the crosslinker and the consequent nucleophilic reaction between the epoxide ring of ECH and the primary amine of CS, which was then characterized by 1H nuclear (1H NMR), Fourier transform infrared (FT-IR) spectra, X-ray diffraction (XRD) analysis, scanning electron microscope (SEM), thermogravimetry (TG), and N2 adsorption/desorption isotherms. When etoposide (VP16), an anti-cancer drug, was encapsulated in the CS-g-ß-CD, the encapsulation ratio was up to 73.6%. Finally, the resultant CS-g-ß-CD was successfully used as the responsive drug carrier for pH- and thermo-sensitive release of VP16. This work opens a new avenue for the preparation of stimuli-responsive drug carriers with modified natural polysaccharides.


Asunto(s)
Ácido Algínico/química , Antineoplásicos Fitogénicos/química , Quitosano/química , Preparaciones de Acción Retardada/síntesis química , Portadores de Fármacos/síntesis química , Etopósido/química , beta-Ciclodextrinas/química , Composición de Medicamentos/métodos , Liberación de Fármacos , Humanos , Concentración de Iones de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Cinética , Porosidad , Temperatura
16.
Oncotarget ; 8(53): 91530-91541, 2017 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-29207663

RESUMEN

MicroRNA-218 (miR-218) has been implicated in the development and progression of multiple cancers. We investigated the role of miR-218 in ovarian cancer progression. We found that miR-218 expression levels were lower in ovarian cancer tissues and cell lines than in adjacent normal tissues or a normal ovarian cell line.miR-218 levels associated with International Federation of Gynecology and Obstetrics (FIGO) stage and lymph node metastasis. Exogenous expression of miR-218 inhibited cell proliferation, colony formation, migration, and invasion in vitro and suppressed tumor growth in a tumor-bearing nude mouse model. Runt-related transcription factor 2 (RUNX2) was identified as a direct functional target of miR-218, and its expression was inversely correlated with miR-218 expression in ovarian cancer tissues. RUNX2 overexpression rescued the suppressive effect of miR-218 on ovarian cancer cell proliferation, colony formation, migration, and invasion. These findings highlight an important role played bymiR-218 in the regulation of cancer growth and metastasis, in part by repressing RUNX2, and revealed the potential of miR-218 as a new therapeutic target inovarian cancer.

17.
Rev Sci Instrum ; 80(5): 053704, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19485513

RESUMEN

Low capacitance measurement is involved in many industrial applications, especially in the applications of electrical capacitance tomography (ECT). Most of the low capacitance measurement circuits employ an ac-based method or a charge/discharge method because of high sensitivity, high resolution, and immunity to stray capacitance; and its excitation or charge voltage are not more than 20 V. When ECT techniques for large industrial equipment such as blast furnaces or grain barns are explored, the existing methods for measuring low capacitance have some limitations. This paper proposes a high excitation voltage ac-based method for measuring low capacitance to improve the resolution of measurement. The method uses a high excitation voltage of several hundred volts and a transformer ratio arms as the C/V transducer. Experimental results indicate that the new method has a resolution of 0.005 fF, a good stability (about 0.003 fF over 4 h) and linearity (0.9992).

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