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1.
Poult Sci ; 103(5): 103620, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38492249

RESUMO

Chicken ovarian follicle development is regulated by complex and dynamic gene expression. Nuclear receptor 5A1 and 5A2 (NR5A1 and NR5A2, respectively) are key genes that regulate steroid hormone production and gonadal development in mammals; however, studies on follicular development in the chicken ovary are scarce. In this study, we investigated the functions of NR5A1 and NR5A2 on follicle development in chickens. The results showed that the expression of NR5A1 and NR5A2 was significantly higher in small yellow follicles and F5. Furthermore, the expression of NR5A1 and NR5A2 was significantly higher in follicular tissues of peak-laying hens (30 wk) than in follicular tissues of late-laying hens (60 wk), with high expression abundance in granulosa cells (GC). The overexpression of NR5A1 and NR5A2 significantly promoted proliferation and inhibited apoptosis of cultured GC; upregulated STAR, CYP11A1, and CYP19A1 expression and estradiol (E2) and progesterone (P4) synthesis in GC from preovulatory follicles (po-GC); and increased STAR, CYP11A1, and CYP19A1 promoter activities. In addition, follicle-stimulating hormone treatment significantly upregulated NR5A1 and NR5A2 expression in po-GC and significantly promoted FSHR, CYP11A1, and HSD3B1 expression in GC from pre-hierarchical follicles and po-GC. The core promoter region of NR5A1 was identified at the -1,095- to -483-bp and -2,054- to -1,536-bp regions from the translation start site (+1), and the core promoter region of NR5A2 was at -998 to -489 bp. Two single nucleotide polymorphisms (SNP) were identified in the core promoter region of the NR5A1 gene, which differed between high- and low-yielding chicken groups. Our study suggested that NR5A1 and NR5A2 promoted chicken follicle development by promoting GC proliferation and E2 and P4 hormone synthesis and inhibiting apoptosis. Moreover, we identified the promoter core region or functional site that regulates NR5A1 and NR5A2 expression.


Assuntos
Apoptose , Proteínas Aviárias , Proliferação de Células , Galinhas , Células da Granulosa , Folículo Ovariano , Animais , Feminino , Galinhas/genética , Células da Granulosa/fisiologia , Células da Granulosa/metabolismo , Folículo Ovariano/fisiologia , Folículo Ovariano/metabolismo , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Fator Esteroidogênico 1/genética , Fator Esteroidogênico 1/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Hormônios Esteroides Gonadais/biossíntese
2.
J Med Chem ; 67(3): 1982-2003, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38261008

RESUMO

Induction of immunogenic cell death (ICD) and activation of the cyclic GMP-AMP synthase stimulator of interferon gene (cGAS-STING) pathway are two potent anticancer immunotherapeutic strategies in hepatocellular carcinoma (HCC). Herein, 12 liver- and mitochondria-targeting gold(I) complexes (9a-9l) were designed and synthesized. The superior complex 9b produced a considerable amount of reactive oxygen species (ROS) and facilitated DNA excretion, the ROS-induced ICD and DNA activated the cGAS-STING pathway, both of which evoked an intense anticancer immune response in vitro and in vivo. Importantly, 9b strongly inhibited tumor growth in a patient-derived xenograft model of HCC. Overall, we present the first case of simultaneous ICD induction and cGAS-STING pathway activation within the same gold-based small molecule, which may provide an innovative strategy for designing chemoimmunotherapies for HCC.


Assuntos
Carcinoma Hepatocelular , Ouro , Morte Celular Imunogênica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , DNA/metabolismo , Morte Celular Imunogênica/efeitos dos fármacos , Imunoterapia , Interferons , Neoplasias Hepáticas/tratamento farmacológico , Mitocôndrias/metabolismo , Nucleotidiltransferases/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais , Ouro/farmacologia , Ouro/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico
3.
Angew Chem Int Ed Engl ; 62(42): e202311335, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37646093

RESUMO

Ni-based catalysts have been widely studied in the hydrogenation of CO2 to CH4 , but selective and efficient synthesis of higher alcohols (C2+ OH) from CO2 hydrogenation over Ni-based catalyst is still challenging due to successive hydrogenation of C1 intermediates leading to methanation. Herein, we report an unprecedented synthesis of C2+ OH from CO2 hydrogenation over K-modified Ni-Zn bimetal catalyst with promising activity and selectivity. Systematic experiments (including XRD, in situ spectroscopic characterization) and computational studies reveal the in situ generation of an active K-modified Ni-Zn carbide (K-Ni3 Zn1 C0.7 ) by carburization of Zn-incorporated Ni0 , which can significantly enhance CO2 adsorption and the surface coverage of alkyl intermediates, and boost the C-C coupling to C2+ OH rather than conventional CH4 . This work opens a new catalytic avenue toward CO2 hydrogenation to C2+ OH, and also provides an insightful example for the rational design of selective and efficient Ni-based catalysts for CO2 hydrogenation to multiple carbon products.

4.
J Med Chem ; 66(6): 3934-3952, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36827091

RESUMO

Immunogenic cell death (ICD) is a promising direction of cancer immunotherapy in hepatocellular carcinoma (HCC). A series of novel NHC-Au(I) complexes derived from 4,5-diarylimidazole, containing glycyrrhetinic acid (GA) as an efficient targeting ligand for HCC, were herein designed and synthesized. Among these, complex 4C exhibited excellent effectiveness for tumor targeting and antitumor activity, which induced the occurrence of ICD in HCC cells. Additionally, 4C can effectively inhibit TrxR enzyme activity, increase reactive oxygen species (ROS) expression, lead to redox homeostasis disorder, mediate mitochondrial dysfunction and endoplasmic reticulum stress (ERS), and cause the characteristic discharge of damage-associated molecular patterns (DAMPs) in HCC cells. More importantly, 4C showed a great ICD-inducing effect in a vaccination mouse model and activated antitumor immunity in a tumor-bearing C57BL/6 mouse model, which is consistent with the in vitro results. In conclusion, we found the potential of Au(I) complex with HCC-targeted capability for effective tumor immunotherapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Morte Celular Imunogênica , Proliferação de Células , Camundongos Endogâmicos C57BL , Linhagem Celular Tumoral
5.
Poult Sci ; 102(3): 102453, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36621102

RESUMO

Several previous reports have suggested that estrogen (E2) is a vital signal responsible for the regulation of skeletal homeostasis and bone remodeling in mammals. E2 could efficiently accelerate the growth of medullary bone in pullets during sexual maturity. Furthermore, the low E2 level can strengthen the mechanical bone functions in female hens. However, mechanistic studies to describe the effects of E2 on bone in pullets during the initiation of the puberty period are remaining elusive. Therefore, the aim of this study was to explore the effect of inhibiting E2 biosynthesis on the biomechanical properties and its molecular mechanism during sexual maturity of pullets. In this study, a total of 90 Hy-line Sonia pullets with comparable body weight at 13 wk of age were selected and categorized into 2 separate groups. Daily, 0.5 mg/4 mL of letrozole (LZ) was orally administered to the treatment (TRT) group and 4 mL of saline to the control (CON) group of pullets for 6 wk. Compared with the CON group, a lower plasma E2 level was observed in the TRT group. Furthermore, plasma P, Gla protein (BGP), and 1,25-dihydroxy vitamin D3 (1,25-(OH)2D3) levels were markedly suppressed, whereas the plasma alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP) levels were significantly elevated. Moreover, the cortical bone thickness and breaking strength of the tibia and femur, the bone mineral density of the humerus, and the bone mineral content of the humerus as well as the femur were increased significantly. The expression levels of 340 differentially expressed genes (DEGs) differed significantly between the CON and TRT group in the tibia at 19 wk of age. Among them, 32 genes were up-regulated, whereas 308 were down-regulated in the TRT group. The variations in candidate genes associated with osteoclast differentiation and cell adhesion may indicate that LZ inhibits E2 biosynthesis, consequently, reduces osteoclast differentiation by suppressing inter-cellular communication and cells attaching to extracellular matrix components. Taken together, the present study demonstrated that inhibiting E2 synthesis during sexual maturity of pullets decreased osteoclast differentiation and considerably enhanced bone quality.


Assuntos
Galinhas , Osteoclastos , Feminino , Animais , Galinhas/fisiologia , Transcriptoma , Maturidade Sexual , Estrogênios , Letrozol , Diferenciação Celular , Mamíferos
6.
Front Mol Neurosci ; 15: 970649, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36466803

RESUMO

Background: Hao-fountain syndrome (HAFOUS) is a neurodevelopmental syndrome characterized by global developmental and severe language delays, behavioral abnormalities (including autism), and mild dysmorphic impairment of intellectual development. It is a dominant genetic disease caused by USP7 gene (*602519) mutations on chromosome 16p13.2. So far, only 15 cases with 14 deleterious variants in the USP7 gene have been reported. Materials and methods: This study describes three unrelated patients with USP7 variants. Besides, we identified novel de novo heterozygous USP7 variants using trio-whole exome sequencing and verified by Sanger sequencing. Furthermore, clinical characteristics were evaluated by reviewing the medical records. Results: The three identified variants, i.e., one frameshift variant (c.247_250del, p.Glu83Argfs × 18) and two missense variants (c.992A > G, p.Tyr331Cys; c.835T > G, p.Leu279Val) are unreported. The predominant clinical manifestations of the three patients included: DD/ID; language impairment; abnormal behavior; abnormal brain magnetic resonance (dilation of lateral ventricles, dilation of Virchow-Robin spaces, dilated the third ventricle, abnormal cerebral white matter morphology in bilateral occipital lobes, hypodysplasia of the corpus callosum, arachnoid cyst, delayed myelination, and widened subarachnoid space); some also had facial abnormalities. Conclusion: In summary, DD/ID is the most prevalent clinical phenotype of HAFOUS, although some patients also exhibit language and behavioral abnormalities. For the first time in China, we identified three variants of the USP7 gene using whole-genome sequence data. This work expands the USP7 gene mutation spectrum and provides additional clinical data on the clinical phenotype of HAFOUS.

7.
Redox Biol ; 54: 102351, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35671636

RESUMO

The nonnegligible reason for the poor prognosis of hepatocellular carcinoma (HCC) is resistance to conventional chemotherapy. Immunogenic cell death (ICD) is a rare immunostimulatory form of cell death that can reengage the tumor-specific immune system. ICD can improve the clinical outcomes of chemotherapeutics by promoting a long-term cancer immunity. The discovery of potential ICD inducers is emerging as a promising direction. In the present study, micheliolide (MCL), a natural guaianolide sesquiterpene lactone, was screened out by the virtual screening strategies, identified as an inhibitor of thioredoxin reductase (TrxR) and was evaluated to have high potential to induce ICD. Here, we showed that MCL induced ICD-associated DAMPs (damage-associated molecular patterns, such as CRT exposure, ATP secretion and HMGB1 release). MCL significantly triggered the regression of established tumors in an immunocompetent mouse vaccine model, and induced ICD (DCs maturation, the stimulation of CD4+, and CD8+ T-cells responses) in vivo. Mechanistically, we found that the magnitude of ICD-associated effects induced upon exposure of HCC cells to MCL was dependent on the generation of reactive oxygen species (ROS)-mediated endoplasmic reticulum stress (ERS). In addition, the suppression of ROS normalized MCL-induced ERS, in contrast, the downregulation of TrxR synergized with the ERS driven by MCL. We also systematically detected the H2O2 generation using Hyper7 sensors in HCC cells exposed to MCL. Notably, MCL inhibited the development of HCC organoids. Collectively, our results reveal a potential association between the TrxR inhibitors and ICD, presenting valuable insights into the MCL-activated ICD in HCC cells.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático , Peróxido de Hidrogênio/farmacologia , Morte Celular Imunogênica , Neoplasias Hepáticas/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Tiorredoxina Dissulfeto Redutase
9.
Animals (Basel) ; 12(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35158638

RESUMO

In this study, soybean oil, lard and mixed oils were added to the feed in two concentrations (1.5% and 3% of each), resulting in six experimental groups. The control group was fed with a base diet without additions, and used to compare the effects of feeding on production performance and egg quality of laying hens. The results demonstrated that: (1) the 3% supplemented-oils or lard group showed a decrease in laying rate; (2) 1.5% and 3% added-lard significantly increased the total amount of unsaturated fatty acids in eggs, compared to the control group; (3) 1.5% and 3% soybean oil increased the content of mono/polyunsaturated fatty acids, cholesterol, phospholipids and choline in eggs; (4) glutathione peroxidase (GPx) and superoxide dismutase (SOD) contents were increased in all groups, being the most evident in the lard-treated group; (5) all experimental groups showed an increase in the content of essential and non-essential amino acids in albumen; (6) 3% oils, especially the mixed oils, damaged the structure of globules of cooked egg yolks. Therefore, the use of 1.5% soybean oil in the feed diet of Hyline brown hens resulted in the most adequate oil to ensure animal health and economic significant improvements in this experiment.

10.
Poult Sci ; 100(9): 101368, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34314937

RESUMO

The blood gas and biochemical reference range established with i-STAT clinical analyzer in avian has become common, however, the reference value for various laying hen lines is limited. Therefore, blood gas and biochemical reference intervals will be established for Lohmann Silver layers in the pre- and post-laying periods. The blood sample was collected at a 4-wk interval. A total of 230 Lohmann Silver layers including 80 pullets (5-17 wk) and 150 laying hens (21-37 wk) were collected for whole blood measurement with the i-STAT clinical analyzer. The CG8+ cartridge provides values of the following 13 parameters: sodium (Na mmol/L), potassium (K mmol/L), ionized calcium (iCa mmol/L), glucose (Glu mg/dL), hematocrit (Hct% Packed Cell Volume [PCV]), pH, partial pressure carbon dioxide (PCO2 mm Hg), partial pressure oxygen (PO2 mm Hg), total concentration carbon dioxide (TCO2 mmol/L), bicarbonate (HCO3 mmol/L), base excess (BE mmol/L), oxygen saturation (sO2%), and hemoglobin (Hb g/dL). The correlation of these parameters and the effect of physiological status were investigated. The reference value interval was established with a reference value advisor for pre-laying and post-laying birds. Correlations were found to be statistically significant, especially between BE and HCO3 and TCO2. Besides, values in Na, iCa, K, Hct, Hb, sO2 differed significantly between the pre- and post-laying periods. Data in this study might serve as important information for facilitating the genetic selection and assessing the health of Lohmann Silver laying hens.


Assuntos
Gasometria/veterinária , Galinhas , Animais , Galinhas/metabolismo , Feminino , Valores de Referência , Sódio
11.
Exp Hematol Oncol ; 10(1): 27, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33836835

RESUMO

BACKGROUND: The receptor tyrosine kinase FLT3 with internal tandem duplications within the juxtamembrane domain (FLT3-ITD) is a poor prognostic factor; however, the prognostic significance of missense mutation in the tyrosine kinase domain (FLT3-TKD) is controversial. Furthermore, the accompanying mutations and fusion genes with FLT3 mutations are unclear in acute myeloid leukemia (AML). METHODS: We investigated FLT3 mutations and their correlation with other gene mutations and gene fusions through two RNA-seq based next-generation sequencing (NGS) method and prognostic impact in 207 de novo AML patients. RESULTS: FLT3-ITD mutations were positive in 58 patients (28%), and FLT3-TKD mutations were positive in 20 patients (9.7%). FLT3-ITD was associated with a higher white blood cell count (WBC, mean 72.9 × 109/L vs. 24.2 × 109/L, P = 0.000), higher bone marrow blasts (mean 65.9% vs. 56.0%, P = 0.024), and NK-AML (normal karyotype) (64.8% vs. 48.4%, P = 0.043). NPM1 and DNMT3A mutations were enriched in FLT3-ITD (53.5% vs. 15.3%, P = 0.000; 34.6% vs. 13%, P = 0.003). However, the mutations of CEBPA were excluded in FLT3-AML (3.8% vs. 0% vs. 19.8%, P = 0.005). Mutations of Ras and TP53 were unlikely associated with FLT3-ITD (1.9% vs. 20.6%, P = 0.006; 0% vs. 6.1%, P = 0.04). The common fusion genes (> 10%) in FLT3-ITD had MLL-rearrangement and NUP98-rearrangement, while the common fusion genes in FLT3-TKD had AML1-ETO and MLL-rearrangement. Two novel fusion genes PRDM16-SKI and EFAN2-ZNF238 were identified in FLT3-ITD patients. Gene fusions and NPM1 mutation were mutually excluded in FLT3-ITD and FLT3-TKD patients. Their patterns of mutual exclusivity and cooperation among mutated genes suggest that additional driver genetic alterations are required and reveal two evolutionary patterns of FLT3 pathogenesis. Patients with FLT3-ITD had a lower CR (complete remission) rate, lower 3-year OS (overall survival), DFS (disease-free survival), and EFS (event-free survival) compared to FLT3wtAML. NK-AML with FLT3-ITD had a lower 3-year OS, DFS, and EFS than those without, while FLT3-TKD did not influence the survival in whole cohort and NK-AML. Besides, we found that FLT3-ITD/TET2 bimutation defined a poor prognostic subgroup. CONCLUSIONS: Our study offers deep insights into the molecular pathogenesis and biology of AML with FLT3-ITD and FLT3-TKD by providing the profiles of concurrent molecular alterations and the clinical impact of FLT3-ITD and FLT3-TKD on AML patients.

12.
Mol Clin Oncol ; 14(1): 16, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33312563

RESUMO

The genomic landscape of metastatic renal cell carcinoma (RCC) is not well understood, and currently available data suggest that it is functionally distinct from that of localized tumors. Additionally, the large number of approved and trial agents used to treat metastatic RCC likely cause selective adaptations in the tumors. Circulating tumor DNA (ctDNA) is a platform to non-invasively determine the genomic profiles of these tumors. The objectives of the present study were to corroborate previous ctDNA studies in metastatic RCC, to identify novel mutations in metastatic RCC, and to compare ctDNA profiles obtained from plasma and urine in patients with metastatic RCC. ctDNA sequencing using the plasma and urine of 50 patients with metastatic RCC who received ctDNA profiling as part of routine clinical care at a single institution was performed using an investigational 120-gene panel. Genomic alterations (GAs) were identified in all 50 patients. The genes with the most GAs were GNAS, PTEN, MYC, MET and HNF1A and novel mutations in additional genes were identified. A significant correlation between the number of GAs detected in matched urine and plasma samples was also identified, but only 28.1% of GAs detected in plasma samples were also detected in matched urine samples. The results of the present study were consistent with those of the largest previous study of ctDNA from patients with metastatic RCC and may help identify additional potential targets for the treatment of such patients.

13.
Histol Histopathol ; 35(8): 827-831, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32286677

RESUMO

BACKGROUND: miR-20b is a member of the miR-106a-363 gene cluster located in the mammalian X chromosome, the larger miR-17 family, and the miR-17-92 and miR-106b-25 gene clusters. Previous studies have indicated that miR-20b may function as oncogene or tumor suppressor in different types of cancers. The present study analyzed the association between miR-20b and clinicopathological characteristics of patients with prostate cancer. METHODS: A total of 127 pairs of prostate cancer tissue samples and adjacent prostate tissue samples were collected from April 2013 to March 2018. The associations between miR-20b expression levels and clinicopathological factors were assessed using the χ2­test. Survival was estimated using the Kaplan-Meier method, and the differences in survival according to miR-20b expression were compared using the log-rank test. Prognostic values of miR-20b expression and clinical outcomes were evaluated by Cox regression analysis. RESULTS: The relative expression of miR-20b in prostate cancer tissues was significantly higher than that in adjacent noncancerous prostate tissues (P<0.001). miR-20b expression was observed to be significantly associated with Gleason score (P<0.001), lymph node metastasis (P<0.001), and TNM stage (P=0.002). The log-rank test indicated that patients with increased miR-20b expression experienced poor overall survival (P=0.037). Multivariate Cox regression analysis showed that miR-20b expression level (HR=2.181, 95% CI: 1.772-9.021, P=0.016) was an independent factor in predicting the overall survival of prostate cancer patients. CONCLUSION: The present study demonstrated that tissue miR-20b expression level could be a promising biomarker of prognosis in prostate cancer.


Assuntos
Biomarcadores Tumorais/genética , MicroRNAs/biossíntese , Neoplasias da Próstata/patologia , Idoso , Humanos , Masculino , MicroRNAs/análise , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/genética
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 24-28, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027248

RESUMO

OBJECTIVE: To investigate the clinical manifestations and laboratory features of B-ALL patients with EP300-ZNF384 fusion gene positive, so as to improve the understanding of this subtype disease. METHODS: The clinical data of 3 B-ALL patients with EP300-ZNF384 fusion gene positive admitted in Department of Hematology, the first medical center of Chinese PLA general hospital from February 2017 to February 2018 were collected and analyzed retrospectively. The clinical and laboratory characteristics as well as the therapentic outcome in B-ALL patients with EP300-ZNF384 fusion gene positive were analyzed. RESULTS: The fusion gene of EP300-ZNF384 was detected in 8.1%(3/37) of B-ALL patients. All cases showed the normal karyotype and aberrant CD13 and/or CD33 expression for immunophenotype. 3 patients were sensitive to traditional chemotherapy. CONCLUSION: The B-ALL with EEP300-ZNF384 fusion gene positive may be a subgroup of B-ALL with a uniqe clinical characteristis and laboatorial features. EP300-ZNF384 positive patients show a good response to conventional chemotherapy, suggesting a favorable prognosis.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Proteína p300 Associada a E1A , Humanos , Proteínas de Fusão Oncogênica , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Estudos Retrospectivos , Transativadores , Fatores de Transcrição
15.
RSC Adv ; 10(37): 22126-22136, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35516627

RESUMO

Micro-mesoporous ZSM-5 with different Si/Al ratios (MZ-X, X = 27, 80, 150) were synthesized by adding microcrystalline cellulose (MCC) as co-template into the hydrothermal synthesis process of zeolites. The resultant ZSM-5 were used for catalytic cracking of high density polyethylene (HPDE) and polypropylene. It was found that introduction of MCC significantly enhanced the formation of mesopores and strong acid sites. MZ-27 achieved the highest oil yield: 21.5% for HPDE and 32.1% for polypropylene, and the light aromatics (BTEX) selectivity therein were 87.6% and 79.7%, respectively. HZ-150 (MCC-free ZSM-5, Si/Al = 150) achieved the highest gas yield: 85.4% for HDPE and 76.7% for polypropylene, and the light olefins (C[double bond, length as m-dash] 2-4) selectivity therein were 44% and 48.3%, respectively. The dense acidic sites and mesoporous structure of MZ-27 were responsible for its better activity for producing aromatic products. The moderate acidity and microporous structure of HZ-150 were helpful for producing light olefins from catalytic cracking of polyolefin plastics.

16.
Org Lett ; 21(23): 9386-9390, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31724404

RESUMO

A nickel-catalyzed transformation of diazoacetates to α-carbonyl methylene radicals has been disclosed in the presence of hyperoxide using ethanol as a hydrogen source and solvent. This strategy is successfully applied in the formation of indolin-2-ones or 1,4-dicarbonyl compounds from acrylamides or enamides in moderate to good yields. These reactions undergo radical addition onto C-C double bonds followed by a cyclization/oxidation or an oxidation/hydrolysis process, respectively.

17.
Poult Sci ; 97(12): 4187-4192, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30107614

RESUMO

Avian leukosis virus (ALV) is a tumor-inducing virus that spreads among most chicken species, causing serious financial losses for the poultry industry. Subgroup J avian leukosis virus (ALV-J) is a recombinant exogenous ALV, which shows more extensive host range in comparison with other subgroups, especially in Chinese local chickens. To identify the relationship between ALV-J host range and the polymorphism of its cellular receptors, we performed a wide range epidemiological investigation of current ALV-J infection in Chinese local chickens, and discovered that all the 18 local chicken breeds being investigated from main local chicken breeding provinces were ALV-J positive. Furthermore, we cloned ALV-J cellular receptor genes of chNHE1 and chANXA2 of these 18 chicken breeds. Sequence alignment demonstrated that despite several regular mutations at the nucleotide level, there were no corresponding amino acid mutations for either chNHE1 gene or chANXA2 gene. Additionally, virus entry assay indicated that the level of viral enter into cells is stable among different chicken breeds. Results of this study indicated that the wide host range of ALV-J in Chinese local chickens was partially due to the high conservatism of its cellular receptors, and also provide target sites for drug design of resistance to ALV-J infection.


Assuntos
Vírus da Leucose Aviária/fisiologia , Leucose Aviária/genética , Proteínas Aviárias/genética , Galinhas , Especificidade de Hospedeiro , Doenças das Aves Domésticas/genética , Receptores Virais/genética , Animais , Leucose Aviária/virologia , Polimorfismo Genético , Doenças das Aves Domésticas/virologia
18.
Water Sci Technol ; 2017(3): 770-781, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30016295

RESUMO

A magnetic cation-exchange resin (MCER) was prepared by copolymerization of oleic acid-grafted magnetite with styrene, divinylbenzene (DVB), and triallylisocyanurate (TAIC) for removing Cd(II) from wastewater. A non-magnetic cation-exchange polystyrene resin (CEPR) was also prepared as a reference. Structural and morphological analyses revealed that the MCER and CEPR were mesoporous microspheres; the MCER contained about 25% Fe3O4. The influence of temperature, pH, contact time, and the initial concentration of Cd(II) on the adsorption of Cd(II) was investigated. The maximum adsorption capacity of the MCER reached 88.56 mg/g, which was achieved at 343 K using a Cd(II) initial concentration of 200 mg/L. The adsorption processes attained equilibrium within 120 min for the MCER and 300 min for the CEPR, and were well described by a pseudo-second-order kinetic model. Furthermore, the equilibrium adsorption data fitted the Freundlich isotherm model better than the Langmuir model. The superior magnetic response and regeneration of the MCER make it a good candidate as an adsorbent for removing Cd(II) from wastewater.


Assuntos
Cádmio/química , Resinas de Troca de Cátion/química , Poliestirenos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Adsorção , Cátions/análise , Óxido Ferroso-Férrico , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Purificação da Água/métodos
19.
Chem Commun (Camb) ; 52(3): 489-92, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26529597

RESUMO

A simple iron-catalyzed aerobic oxidative C-C σ-bond cleavage of ketones has been developed. Readily available and environmentally benign air is used as the oxidant. This reaction avoids the use of noble metal catalysts or specialized oxidants, chemoselectively yielding carbon chain-shortened aldehydes, ketones and 1,2-dicarbonyl compounds without overoxidation.

20.
J Org Chem ; 80(12): 6213-21, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-25985116

RESUMO

An efficient nickel catalyst system for the direct ortho C-H alkynylation of the amides has been successfully developed with the directing assistance of 8-aminoquinoline. It was found that the flexible bis(2-dimethylaminoethyl) ether (BDMAE) ligand was critical to achieve the optimized reactivity. This protocol showed good tolerance toward not only a wide range of (hetero)aryl amides but also the rarely studied α,ß-unsaturated alkenyl amide. The directing amide group could be easily transformed to aldehyde or ester in high yields. Meanwhile, the removable TIPS substituent on the resultant aryl/alkenyl alkynes could be further converted to an aryl moiety through a Sila-Sonogashira coupling reaction. This Ni-catalyzed alkynylation procedure provides an alternative approach to construct a C(sp(2))-C(sp) bond.

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