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1.
Commun Biol ; 7(1): 1074, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223327

RESUMO

Target-aware drug discovery has greatly accelerated the drug discovery process to design small-molecule ligands with high binding affinity to disease-related protein targets. Conditioned on targeted proteins, previous works utilize various kinds of deep generative models and have shown great potential in generating molecules with strong protein-ligand binding interactions. However, beyond binding affinity, effective drug molecules must manifest other essential properties such as high drug-likeness, which are not explicitly addressed by current target-aware generative methods. In this article, aiming to bridge the gap of multi-objective target-aware molecule generation in the field of deep learning-based drug discovery, we propose ParetoDrug, a Pareto Monte Carlo Tree Search (MCTS) generation algorithm. ParetoDrug searches molecules on the Pareto Front in chemical space using MCTS to enable synchronous optimization of multiple properties. Specifically, ParetoDrug utilizes pretrained atom-by-atom autoregressive generative models for the exploration guidance to desired molecules during MCTS searching. Besides, when selecting the next atom symbol, a scheme named ParetoPUCT is proposed to balance exploration and exploitation. Benchmark experiments and case studies demonstrate that ParetoDrug is highly effective in traversing the large and complex chemical space to discover novel compounds with satisfactory binding affinities and drug-like properties for various multi-objective target-aware drug discovery tasks.


Assuntos
Descoberta de Drogas , Método de Monte Carlo , Conscientização , Descoberta de Drogas/métodos , Humanos , Aprendizado de Máquina
2.
Animals (Basel) ; 14(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39199871

RESUMO

Using 0.5% and 1.0% MGM-P, the objective of the present study was to determine a more appropriate additive level for early-weaned piglets as an alternative to the use of antibiotics. Thirty-six weaned piglets were allotted to one of four groups and given a basal diet (NC), with the basal diet containing either 0.5% (LT) or 1.0% (HT) MGM-P or antibiotics (PC). Diarrhea incidence, growth performance, hematology, blood biochemistry, and blood amino acid concentrations were monitored during the experimental period. Three piglets per group with a body weight nearest to the average level were slaughtered after the experiment to assess their organ index. The results showed that no diarrhea was observed either in the treatment groups or in the control group. The 0.5% group showed an upward trend in body weight and average daily gain at all stages. The WBC counts at 21 days of age were higher (p > 0.05) both in the MGM-P addition groups and the LT and HT groups. For some of the plasma amino acids, such as arginine, phenylalanine concentrations were significantly lower (p < 0.05) in the HT group at the end of the trial. The pathological examination of all organs confirmed no differences. Consequently, the 0.5% MGM-P addition level may be suggested as a potential alternative to the use of antibiotic additives. Even with additives as high as 1%, there is no negative effect on ADG and FCR.

3.
Adv Sci (Weinh) ; : e2403473, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101248

RESUMO

As a form of dementia, Alzheimer's disease (AD) suffers from no efficacious cure, yet AD treatment is still imperative, as it ameliorates the symptoms or prevents it from deteriorating or maintains the current status to the longest extent. The human brain is the most sensitive and complex organ in the body, which is protected by the blood-brain barrier (BBB). This yet induces the difficulty in curing AD as the drugs or nanomaterials that are much inhibited from reaching the lesion site. Thus, BBB crossing capability of drug delivery system remains a significant challenge in the development of neurological therapeutics. Fortunately, nano-enabled delivery systems possess promising potential to achieve multifunctional diagnostics/therapeutics against various targets of AD owing to their intriguing advantages of nanocarriers, including easy multifunctionalization on surfaces, high surface-to-volume ratio with large payloads, and potential ability to cross the BBB, making them capable of conquering the limitations of conventional drug candidates. This review, which focuses on the BBB crossing ability of the multifunctional nanomaterials in AD diagnosis and treatment, will provide an insightful vision that is conducive to the development of AD-related nanomaterials.

4.
Research (Wash D C) ; 7: 0340, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38665846

RESUMO

The methylation of adenosine base at the nitrogen-6 position is referred to as "N6-methyladenosine (m6A)" and is one of the most prevalent epigenetic modifications in eukaryotic mRNA and noncoding RNA (ncRNA). Various m6A complex components known as "writers," "erasers," and "readers" are involved in the function of m6A. Numerous studies have demonstrated that m6A plays a crucial role in facilitating communication between different cell types, hence influencing the progression of diverse physiological and pathological phenomena. In recent years, a multitude of functions and molecular pathways linked to m6A have been identified in the osteogenic, adipogenic, and chondrogenic differentiation of bone mesenchymal stem cells (BMSCs). Nevertheless, a comprehensive summary of these findings has yet to be provided. In this review, we primarily examined the m6A alteration of transcripts associated with transcription factors (TFs), as well as other crucial genes and pathways that are involved in the differentiation of BMSCs. Meanwhile, the mutual interactive network between m6A modification, miRNAs, and lncRNAs was intensively elucidated. In the last section, given the beneficial effect of m6A modification in osteogenesis and chondrogenesis of BMSCs, we expounded upon the potential utility of m6A-related therapeutic interventions in the identification and management of human musculoskeletal disorders manifesting bone and cartilage destruction, such as osteoporosis, osteomyelitis, osteoarthritis, and bone defect.

5.
Sci China Life Sci ; 66(9): 2020-2040, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37526911

RESUMO

The ionome is essential for maintaining body function and health status by participating in diverse key biological processes. Nevertheless, the distribution and utilization of ionome among different organs and how aging impacts the ionome leading to a decline in egg white quality remain unknown. Thus, we used inductively coupled plasma mass spectrometry (ICP-MS) to analyze 35 elements and their isotopic contents in eight organs of laying hens at 35, 72, and 100 weeks. Moreover, the magnum proteome, amino acids in egg white, and egg white quality were analyzed in laying hens at three different ages using 4D proteomics techniques, an amino acid analyzer, and an egg quality analyzer. Across the organs, we identified varying distribution patterns among macroelements (Mg24, Ca43/44, K39, and P31), transition metals (Zn64/66, Cu63/65, Fe56/57, and Mn55), and toxic elements (Pb208, Ba137, and Sr86). We observed an organ-specific aging pattern characterized by the accumulation of toxic elements (Pb208, Ba137, and Sr86) and calcification in the small intestine. Additionally, a decrease in the utilization of essential trace elements selenium (Se78/82) and manganese (Mn55) was noted in the oviduct. By analyzing ionome in tandem with egg quality, egg white amino acids, and proteome, we unveiled that the reduction of selenium and manganese concentrations in the magnum during the aging process affected amino acid metabolism, particularly tryptophan metabolism, thereby inhibiting the amino acid synthesis in the magnum. Furthermore, it accelerated the senescence of magnum cells through necroptosis activation, leading to a decline in the albumen secretion function of the magnum and subsequently reducing egg white quality. Overall, this study provides insights into the evolution of 35 elements and their isotopes across 8 organs of laying hens with age. It also reveals the elemental composition, interactions, and utilization patterns of these organs, as well as their correlation with egg white quality. The present study highlights the significance of ionome and offers a comprehensive perspective on the selection of ionome for regulating the aging of laying hens.


Assuntos
Clara de Ovo , Selênio , Animais , Feminino , Proteoma/metabolismo , Galinhas , Selênio/metabolismo , Manganês/metabolismo , Aminoácidos/metabolismo , Envelhecimento
6.
Mil Med Res ; 10(1): 31, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37443101

RESUMO

Rheumatoid arthritis (RA) is a systemic autoimmune disease that is primarily manifested as synovitis and polyarticular opacity and typically leads to serious joint damage and irreversible disability, thus adversely affecting locomotion ability and life quality. Consequently, good prognosis heavily relies on the early diagnosis and effective therapeutic monitoring of RA. Activatable fluorescent probes play vital roles in the detection and imaging of biomarkers for disease diagnosis and in vivo imaging. Herein, we review the fluorescent probes developed for the detection and imaging of RA biomarkers, namely reactive oxygen/nitrogen species (hypochlorous acid, peroxynitrite, hydroxyl radical, nitroxyl), pH, and cysteine, and address the related challenges and prospects to inspire the design of novel fluorescent probes and the improvement of their performance in RA studies.


Assuntos
Artrite Reumatoide , Sinovite , Humanos , Corantes Fluorescentes/uso terapêutico , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Sinovite/diagnóstico , Biomarcadores , Espécies Reativas de Nitrogênio/uso terapêutico , Espécies Reativas de Oxigênio
7.
Chem Asian J ; 18(15): e202300367, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37389572

RESUMO

By combining exquisitely designed hairpins with the catalytic hairpin assembly (CHA) to form tripedal DNA walkers driven by enzyme, we constructed a 3D DNA walker with accordingly complementary hairpins attached on gold nanoparticles (AuNPs) and sensitive fluorescence sensing system for the sensitive detection of target miRNA-21 (miR-21). The presence of miR-21 triggers the CHA among three hairpins (HP1, HP2, and HP3), which lead to the formation of the tripedal DNA walkers. For the walking trajectories, FAM-labeled hairpins (HP4) were attached to the surface of AuNPs, the fluorescence of which was initially quenched due to its close proximity to AuNPs. After the binding/cleaving/moving process of tripedal DNA walkers with HP4 driven by Exonuclease III (Exo III), a number of single-stranded DNAs (ssDNAs) will be released with FAM fluorescence recovered. Benefiting from the DNA walker and CHA cascade amplification, the proposed sensing strategy showed remarkable improvement in sensitivity with the LOD of 42 aM. Owing to the precise design of the system, this method exhibited excellent specificity to distinguish miR-21 from its single-, double-mismatched sequences and non-complementary sequences, showing great versatility and potential for the biological analysis and early disease diagnosis.

8.
J Cheminform ; 15(1): 43, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37038222

RESUMO

Artificial intelligence has deeply revolutionized the field of medicinal chemistry with many impressive applications, but the success of these applications requires a massive amount of training samples with high-quality annotations, which seriously limits the wide usage of data-driven methods. In this paper, we focus on the reaction yield prediction problem, which assists chemists in selecting high-yield reactions in a new chemical space only with a few experimental trials. To attack this challenge, we first put forth MetaRF, an attention-based random forest model specially designed for the few-shot yield prediction, where the attention weight of a random forest is automatically optimized by the meta-learning framework and can be quickly adapted to predict the performance of new reagents while given a few additional samples. To improve the few-shot learning performance, we further introduce a dimension-reduction based sampling method to determine valuable samples to be experimentally tested and then learned. Our methodology is evaluated on three different datasets and acquires satisfactory performance on few-shot prediction. In high-throughput experimentation (HTE) datasets, the average yield of our methodology's top 10 high-yield reactions is relatively close to the results of ideal yield selection.

9.
Food Chem ; 419: 136031, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37004363

RESUMO

The purpose of this study was to investigate the mechanism for the differences in heat-induced gel properties of egg white proteins with different interior quality during ageing in laying hens. Quantitative proteomic analysis revealed that the abundance of ovotransferrin, avidin, mucin 5B, and clusterin increased with decreasing Haugh units (HU), leading to the transition from disorder to order in the secondary and tertiary structure of egg white proteins, with the burial of hydrophobic groups and a reduction in the negative charge on the protein surface, rendering the egg white protein solution aggregated. These changes would accelerate the rate of aggregation of egg white proteins during heating, resulting in the loss of orientation of the molecular chains, forming coarse and porous gel structures and poor gel properties. This research provides a new idea for improving the gelling properties of egg whites from lower interior quality during ageing in laying hens.


Assuntos
Galinhas , Temperatura Alta , Animais , Feminino , Galinhas/metabolismo , Proteômica , Proteínas do Ovo/metabolismo , Envelhecimento , Dieta , Ração Animal/análise
10.
Genes (Basel) ; 14(3)2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36980911

RESUMO

Eggshell plays an essential role in preventing physical damage and microbial invasions. Therefore, the analysis of genetic regulatory mechanisms of eggshell quality deterioration during aging in laying hens is important for the biosecurity and economic performance of poultry egg production worldwide. This study aimed to compare the differences in the expression profiles of long non-coding RNAs (lncRNAs) and mRNAs between old and young laying hens by the method of high-throughput RNA sequencing to identify candidate genes associated with aging in the uterus of laying hens. Overall, we detected 176 and 383 differentially expressed (DE) lncRNAs and mRNAs, respectively. Moreover, functional annotation analysis based on the Gene Ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) databases revealed that DE-lncRNAs and DE-mRNAs were significantly enriched in "phosphate-containing compound metabolic process", "mitochondrial proton-transporting ATP synthase complex", "inorganic anion transport", and other terms related to eggshell calcification and cuticularization. Through integrated analysis, we found that some important genes such as FGF14, COL25A1, GPX8, and GRXCR1 and their corresponding lncRNAs were expressed differentially between two groups, and the results of quantitative real-time polymerase chain reaction (qPCR) among these genes were also in excellent agreement with the sequencing data. In addition, our study found that TCONS_00181492, TCONS_03234147, and TCONS_03123639 in the uterus of laying hens caused deterioration of eggshell quality in the late laying period by up-regulating their corresponding target genes FGF14, COL25A1, and GRXCR1 as well as down-regulating the target gene GPX8 by TCONS_01464392. Our findings will provide a valuable reference for the development of breeding programs aimed at breeding excellent poultry with high eggshell quality or regulating dietary nutrient levels to improve eggshell quality.


Assuntos
Galinhas , RNA Longo não Codificante , Animais , Feminino , Galinhas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Útero/metabolismo , Envelhecimento/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
Poult Sci ; 101(8): 101978, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35793599

RESUMO

This study measured the metabolizable energy of soybean meal (SBM) and evaluated effects of soybean meal specific enzymes supplementation in corn-soybean diets on growth performance, intestinal digestion properties and energy values of 28-day-old broilers. A total of 336 one-day-old male AA broiler chickens were distributed to 7 groups in a completely random design. The birds were given 7 diets containing 6 diets with different combined soybean meals and a fasting treatment, 8 replicates per treatment and 6 birds per replicate (Trial 1). A total of 672 one-day-old male AA broiler chickens were randomly allocated to 7 dietary treatments including a control diet and 6 diets supplemented with 300 mg/kg α-galactosidase, 200 mg/kg ß-mannanase, and 300 mg/kg protease individually or in combination (Trial 2). Apparent metabolizable energy (AME) of broilers was measured from d 25 to 27 in both trial 1 and trial 2. The results showed that AME values of combined soybean meals averaged 2,894 kcal/kg. Dietary ß-mannanase and protease supplementation increased body weight gain (P < 0.05) during d 0 to 14, whereas did not affect the growth performance (P > 0.05) during d 14 to 28. Addition of ß-mannanase in combination with other enzymes significantly increased lipase and trypsin content (P < 0.05) in ileum. In addition, dietary ß-mannanase and protease supplementation individually or in combination enhanced trypsin enzyme content in jejunum (P < 0.05). The ß-mannanase enzyme enhanced villus height and villus height to crypt depth ratio (P < 0.05) of ileum compared with control diet. Moreover, supplementation of enzyme except for protease enhanced raffinose and stachyose degradation ratio (P < 0.05). Dietary ß-mannanase supplementation individually or in combination enhanced AME and AMEn values (P < 0.05). This study demonstrated that dietary enzyme supplementation especially ß-mannanase improved intestinal digestion properties and contributed to high energy values.


Assuntos
Galinhas , Glycine max , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Digestão , Masculino , Refeições , Glycine max/metabolismo , Tripsina/metabolismo , Tripsina/farmacologia , beta-Manosidase/metabolismo
12.
Front Nutr ; 9: 747705, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35548562

RESUMO

Growing evidence of intestinal microbiota-muscle axis provides a possibility to improve meat quality of broilers through regulating intestinal microbiota. Water-holding capacity is a crucial factor to evaluate the meat quality. High quality of water-holding capacity is usually described as a low drip-losing rate. This study aimed to explore the relationship between intestinal microbiota and water-holding capacity of muscle in broilers. According to our results, two native breeds of broilers (the Arbor Acres broilers and the Beijing-You broilers) exhibited remarkable differences in microbiota composition. However, the regular of gut bacteria compositions gradually became similar when the two breeds of broiler were raised in a same feeding environment. Therefore, this similar regular of intestinal microbiota induced similar water-holding capacity of the muscle from the two breeds. In subsequent fecal microbiota transplantation (FMT) experiments, the intestinal microbiota community of the Arbor Acres broilers was remodeling by oral gavage of bacterial suspension that was derived from the Beijing-You broilers. Then, not only body weight and abdominal fat rate were increased, but also drip loss of muscle was decreased in the Arbor Acres broilers. Additionally, muscle fiber diameter of biceps femoris muscle and expression of MyoD1 were notably enlarged. Muscle fiber diameter and related genes were deemed as important elements for water-holding capacity of muscle. Simultaneously, we screened typical intestinal bacteria in both the two native breeds of broilers by 16S rDNA sequencing. Lachnoclostridium was the only bacteria genus associated with drip-losing rate, meat fiber diameter, body weight, and abdominal fat rate. Importance: Higher body weight and superior meat quality in livestock imply an adequate source of protein and substantial commercial value. Regulating the intestinal microbiota of broilers is a promising approach to optimize commercial phenotypes. Our results indicate that the intestinal microbiota profile could be reconstructed by external factors, leading to advantageous changes in muscle characteristics. The cecum microbiota of native broilers have the ability to improve certain meat quality and production performance. The population of Lachnoclostridium spp. could be used to regulate body weight and drip-losing rate in broilers, but more study is needed.

13.
Animals (Basel) ; 11(11)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34828046

RESUMO

This study assessed the feasibility of using a vegetable extract, MGM-P (quebracho tannin product), as an alternative to antibiotics for weaned piglets; it investigated MGM-P effects on growth performance, diarrhea, and overall health in early-weaned piglets. In total, 24 piglets were allocated to three treatment groups fed basal diets supplemented with 0, 0.2%, or 0.3% MGM-P for 20 days. The addition of 0.3% MGM-P to the diet of early-weaned piglets improved diarrhea incidence, hematological parameters, and intestinal mucosa structure. Furthermore, the addition of 0.2% or 0.3% MGM-P to the diet of early-weaned piglets did not affect their overall health. Importantly, MGM-P had no effects on average daily gain (ADG), average daily feed intake (ADFI), or feed conversion ratio (FCR). Gut morphology analysis showed that treatment with 0.3% MGM-P enhanced the jejunal villus height (p < 0.05) while reducing the ileal crypt depth (p < 0.05) and colon mucosal thickness (p < 0.05). Collectively, the findings suggested that the use of MGM-P as an alternative to dietary antibiotics could improve diarrhea incidence in early-weaned piglets without negative effects on growth performance or overall health.

14.
Org Biomol Chem ; 18(41): 8433-8442, 2020 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-33057549

RESUMO

A high-efficiency strategy for resin-free and large scale liquid phase synthesis of the anti-SARS octapeptide AVLQSGFR is described. Herein, tri(4'-diphenylphosphonyloxylbenzoyl phenyl)phosphate (TDPBP) derivatives were designed as C-terminal supports to aid octapeptide intermediate purification without the need for chromatographic separation. Furthermore, the ACE inhibitory structure-activity relationship (SAR) of the anti-SARS octapeptide and its alanine-scanning analogues was systematically studied by in vitro assay and 3D-QSAR via molecular docking. This paper provides a new strategy for the development of peptide-based drugs. Simultaneously, a study on the ACE inhibition and structure-activity relationship of the anti-SARS octapeptide also lays a foundation for further understanding how the anti-SARS octapeptide acts as an ACE inhibitor.


Assuntos
Simulação de Acoplamento Molecular
15.
J Med Chem ; 63(21): 12748-12772, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32991173

RESUMO

Farnesoid X receptor (FXR) plays a key role in bile acid homeostasis, inflammation, fibrosis, and metabolism of lipid and glucose and becomes a promising therapeutic target for nonalcoholic steatohepatitis (NASH) or other FXR-dependent diseases. The phase III trial results of obeticholic acid demonstrate that the FXR agonists emerge as a promising intervention in patients with NASH and fibrosis, but this bile acid-derived FXR agonist brings severe pruritus and an elevated risk of cardiovascular disease for patients. Herein, we reported our efforts in the discovery of a series of non-bile acid FXR agonists, and 36 compounds were designed and synthesized based on the structure-based drug design and structural optimization strategies. Particularly, compound 42 is a highly potent and selective FXR agonist, along with good pharmacokinetic profiles, high liver distribution, and preferable in vivo efficacy, indicating that it is a potential candidate for the treatment of NASH or other FXR-dependent diseases.


Assuntos
Ácido Quenodesoxicólico/análogos & derivados , Receptores Citoplasmáticos e Nucleares/agonistas , Animais , Sítios de Ligação , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/patologia , Ácido Quenodesoxicólico/química , Ácido Quenodesoxicólico/metabolismo , Ácido Quenodesoxicólico/farmacocinética , Ácido Quenodesoxicólico/uso terapêutico , Desenho de Fármacos , Avaliação Pré-Clínica de Medicamentos , Meia-Vida , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Ratos , Ratos Sprague-Dawley , Receptores Citoplasmáticos e Nucleares/metabolismo , Relação Estrutura-Atividade
16.
PLoS One ; 15(9): e0237977, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915802

RESUMO

The objective of this study was to determine the radiocesium transfer rates of pigs fed haylage contaminated with low levels of cesium at different growth stages. We measured the body weight of juvenile and adult pigs during the treatment period to confirm their health status. We also performed pig blood hematologic and biochemical analyses at both growth stages. To our knowledge, this is the first study to report pig radiocesium transfer coefficient rates after 1 month of chronic oral treatment, which is the period assumed to be required for body equilibrium under a diet of radiocesium-contaminated food. The results showed higher radiocesium retention rates in the kidneys, liver, spleen, genitals, psoas major, bladder, thyroid, and urine than in the blood and bone (tibia and femur) of pigs at both growth stages. The radiocesium retention levels were generally higher in juvenile pigs than in adult pigs, with the highest transfer coefficient ratio in the kidneys (16.2%).


Assuntos
Radioisótopos de Césio/metabolismo , Contaminação Radioativa de Alimentos/análise , Administração Oral , Animais , Peso Corporal , Radioisótopos de Césio/sangue , Rim/química , Rim/metabolismo , Fígado/química , Fígado/metabolismo , Suínos
17.
J Org Chem ; 85(19): 12097-12107, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-32894019

RESUMO

An interesting Rh(III)-catalyzed dual C-H functionalization/cyclization cascade of azomethine imine with diazophosphonate by a removable directing group for the synthesis of highly fused pyrano[de]isochromene has been achieved. The transformation shows that the desired pyrano[de]isochromenes with two oxygen atoms on its core scaffold could be constructed with good to excellent yields (up to 86%) via a facile one-pot, multiple-step cascade reaction, along with broad generality and versatility.

18.
Front Cell Dev Biol ; 8: 621, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32733898

RESUMO

Oocytes vitrification is frequently applied in assisted reproductive technologies. However, chromosomes segregation was error-prone during meiosis maturation of vitrified oocytes. The fidelity of chromosomes segregation depends on the correct kinetochore-microtubule attachments (KT-MTs). In meiosis I, the Aurora B/C would not spatially separate from the attachment sites upon bivalents stretched. Oocytes lack a mechanism for coordinating bivalent stretching and Aurora B/C inhibition in meiosis I. Thus, the KT-MTs are unstable in oocytes. In this study, we firstly found the incorrect KT-MTs were markedly increased in vitrified oocytes. The Aurora B/C activity in vitrified oocytes was significantly increased when the bivalents were stretched. This Aurora B/C activity could not induce a SAC response, as the SAC protein Mad2 was significantly decreased during MI stage in vitrified oocytes. Thus, the KT-MTs in vitrified oocytes were error-prone. This study, for the first time, revealed the mechanism of the incorrect KT-MTs occurred in vitrified oocytes and provided a theoretical basis for further improvement of oocytes vitrification.

19.
Vet Pathol ; 57(1): 122-131, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31551021

RESUMO

Primary epithelial tumors of the gallbladder are rarely reported in animals. In this study, 9 aged pigs (6-12 years old) were histopathologically examined for gallbladder proliferative lesions. At necropsy, a large gallstone occupied the lumen of the gallbladder of 3 pigs. Histopathological examination revealed chronic cholecystitis in all 9 pigs, mucosal hyperplasia in 2 pigs, adenoma in 1 pig, and adenocarcinoma in 2 pigs. Bacilli were detected in the gallbladder lumen of 6 pigs by Warthin-Starry stain. Mucosal hyperplasia, adenoma, and adenocarcinoma were characterized by papillary projections of the mucosa with occasional acinar structures. Tumor invasion of the surrounding tissue was observed in the cases of adenocarcinoma. On Alcian blue and periodic acid-Schiff double-stained sections, the acinar structure of gallbladder mucosa in chronic cholecystitis and mucosal hyperplasia was stained in a mosaic pattern, indicating pyloric gland metaplasia. The results of immunohistochemistry revealed a CD10-positive epithelial brush border and mucin (MUC) 2-positive goblet cells in chronic cholecystitis, adenoma, and adenocarcinomas, indicating intestinal metaplasia. Immunoreactivity of MUC5 AC and cytokeratin 19 was weaker in adenoma and adenocarcinomas compared with the normal and hyperplastic gallbladder mucosa. The number of p53-positive nuclei and the Ki-67 index were higher in adenocarcinomas compared with benign lesions. These results suggest that chronic cholecystitis associated with gallstones and/or bacterial infections may contribute to metaplastic changes and development of gallbladder tumors in aged pigs. Alteration of mucin, cytokeratin, and p53 profiles in gallbladder proliferative lesions in pigs were similar to that in humans, suggesting a common pathogenesis in tumor development.


Assuntos
Adenocarcinoma/veterinária , Adenoma/veterinária , Biomarcadores Tumorais/metabolismo , Colecistite/veterinária , Neoplasias da Vesícula Biliar/veterinária , Inflamação/veterinária , Doenças dos Suínos/patologia , Adenocarcinoma/patologia , Adenoma/patologia , Fatores Etários , Animais , Carcinogênese , Colecistite/patologia , Doença Crônica/veterinária , Feminino , Vesícula Biliar/patologia , Neoplasias da Vesícula Biliar/patologia , Cálculos Biliares/veterinária , Hiperplasia/patologia , Hiperplasia/veterinária , Imuno-Histoquímica/veterinária , Inflamação/patologia , Masculino , Metaplasia/veterinária , Suínos
20.
Cryobiology ; 89: 68-75, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31082378

RESUMO

Vitrification of germinal vesicle (GV) stage oocytes has been shown to be closely associated with decreased rates of meiosis maturation and increased rates of aneuploidy. However, little is known about the effects of melatonin on these events in mice vitrified GV oocytes. In this study, the effects of melatonin on meiosis maturation potential and the incidence rate of aneuploidy in mouse vitrified oocytes were analyzed by supplementing in vitro maturation (IVM) solution with melatonin at different concentrations. This study, for the first time, showed that the mitochondrial heat production was markedly increased in vitrified oocytes (P < 0.05), which compromised the first polar body extrusion (PBE) of vitrified oocytes (73.3% vs. 85.1%, P < 0.05). However, 10-11 mol/L melatonin could significantly decrease mitochondrial heat production and ROS level (9.1 vs. 12.0 pixels, P < 0.05), meanwhile increase ATP level (1.1 vs. 0.88 pmol, P < 0.05) and mtDNA copies (107438 vs. 67869, P < 0.05), which rescued the abnormal chromosome alignment (32% vs. 69%, P < 0.05) and reduced the incidence of aneuploidy (15.6% vs. 38.5%, P < 0.05) in vitrified oocytes. The meiosis maturation ability of vitrified oocytes with melatonin supplementation was similar to that of fresh ones (83.4% vs. 85.1%, P > 0.05). Collectively, our data revealed that melatonin has a protective action against vitrification-induced injuries of oocytes meiosis maturation.


Assuntos
Aneuploidia , Criopreservação/métodos , Crioprotetores/farmacologia , Meiose/efeitos dos fármacos , Melatonina/farmacologia , Oócitos/fisiologia , Animais , Núcleo Celular , Feminino , Temperatura Alta , Camundongos , Mitocôndrias , Vitrificação
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