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1.
Learn Mem ; 29(1): 29-37, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34911801

RESUMO

Plasticity is a neural phenomenon in which experience induces long-lasting changes to neuronal circuits and is at the center of most neurobiological theories of learning and memory. However, too much plasticity is maladaptive and must be balanced with substrate stability. Area CA3 of the hippocampus provides such a balance via hemispheric lateralization, with the left hemisphere dominant in providing plasticity and the right specialized for stability. Left and right CA3 project bilaterally to CA1; however, it is not known whether this downstream merging of lateralized plasticity and stability is functional. We hypothesized that interhemispheric convergence of input from these pathways is essential for integrating spatial memory stored in the left CA3 with navigational working memory facilitated by the right CA3. To test this, we severed interhemispheric connections between the left and right hippocampi in mice and assessed learning and memory. Despite damage to this major hippocampal fiber tract, hippocampus-dependent navigational working memory and short- and long-term memory were both spared. However, tasks that required the integration of information retrieved from memory with ongoing navigational working memory and navigation were impaired. We propose that one function of interhemispheric communication in the mouse hippocampus is to integrate lateralized processing of plastic and stable circuits to facilitate memory-guided spatial navigation.

2.
Biotechnol Biofuels ; 14(1): 233, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876182

RESUMO

BACKGROUND: Lignocellulosic feedstocks have attracted much attention as a potential carbon source for lactic acid (LA) production because of their ready availability, sustainability, and renewability. However, there are at least two major technical challenges to producing LA from lignocellulose. Inhibitors derived from lignocellulose pretreatment have a negative impact on the growth of cells producing LA. Furthermore, pentose sugars produced from the pretreatment are difficultly utilized by most LA producers, which is known as the carbon catabolite repression (CCR) effect. This complex feedstock can be utilized by a robust microbial consortium with high bioconversion efficiency. RESULTS: In this study, a thermophilic consortium DUT50 producing LA was enriched and employed to improve corn stover (CS) utilization. Enterococcus was the dominant family in the consortium DUT50, accounting for 93.66% of the total abundance, with Lactobacillus, Bacillus, Lactococcus, and Trichococcus accounted for the remaining 2.68%. This consortium could be resistant to inhibitors concentration up to 9.74 g/L (2.88 g/L acetic acid, 2.46 g/L furfural, 2.20 g/L 5-HMF, and 2.20 g/L vanillin derived from pretreatment of CS), and simultaneously metabolizes hexose and pentose without CCR effect. Based on the promising consortium features, an efficient process of simultaneous saccharification and co-fermentation (SSCF) was developed to produce LA from acid pretreated corn stover, in which solid-liquid separation and detoxification were avoided. The key influencing factors were investigated and optimized, including dry biomass and cellulase loading, corn steep liquor powder concentration, and the pre-hydrolysis time. The highest LA titer of 71.04 g/L with a yield of 0.49 g/g-CS was achieved at a dry biomass loading of 20% (w/v), which is the highest LA production from non-detoxified acid pretreated corn stover via the SSCF process without wastewater generation reported to date. The simultaneous metabolism of hexose and pentose revealed collaboration between Enterococcus in the consortium, whereas xylose may be efficiently metabolized by Lactobacillus and Bacillus with low abundance via the pentose phosphate pathway. CONCLUSIONS: The experimental results demonstrated the potential advantage of symbiosis in microbial consortia used for LA production from lignocellulosic biomass.

3.
Angew Chem Int Ed Engl ; : e202115554, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34904775

RESUMO

Here, we report a copper-catalyzed asymmetric cascade cyclization/[1,2]-Stevens-type rearrangement via a non-diazo approach, leading to the practical and atom-economic assembly of various valuable chiral chromeno[3,4-c]pyrroles bearing a quaternary carbon stereocenter in generally moderate to good yields with wide substrate scope and excellent enantioselectivities (up to 99 % ee). Importantly, this protocol not only represents the first example of catalytic asymmetric [1,2]-Stevens-type rearrangement based on alkynes but also constitutes the first asymmetric formal carbene insertion into the Si-O bond.

4.
Nanomaterials (Basel) ; 11(11)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34835625

RESUMO

Artificial synapses and neurons are two critical, fundamental bricks for constructing hardware neural networks. Owing to its high-density integration, outstanding nonlinearity, and modulated plasticity, memristors have attracted emerging attention on emulating biological synapses and neurons. However, fabricating a low-power and robust memristor-based artificial neuron without extra electrical components is still a challenge for brain-inspired systems. In this work, we demonstrate a single two-dimensional (2D) MXene(V2C)-based threshold switching (TS) memristor to emulate a leaky integrate-and-fire (LIF) neuron without auxiliary circuits, originating from the Ag diffusion-based filamentary mechanism. Moreover, our V2C-based artificial neurons faithfully achieve multiple neural functions including leaky integration, threshold-driven fire, self-relaxation, and linear strength-modulated spike frequency characteristics. This work demonstrates that three-atom-type MXene (e.g., V2C) memristors may provide an efficient method to construct the hardware neuromorphic computing systems.

5.
J Inflamm Res ; 14: 5633-5646, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744447

RESUMO

Background: Immune function influenced patients' recovery from major abdominal surgery. The aim of this study is to explore the clinical feasibility of peripheral lymphocyte absolute counts for predicting short-term surgical outcomes in gastric cancer patients after laparoscopic D2 gastrectomy. Methods: This is a prospective cohort study from a single tertiary referral hospital. Patients diagnosed with gastric cancer who met the inclusion criteria were included in this study. We collected the demographic and clinicopathological characteristics of included patients. We monitored perioperative dynamics of absolute counts of peripheral lymphocyte subsets. Predictive factors for length of postoperative hospital stay and complications were investigated in univariate and multivariate analyses. Results: A total of 137 gastric cancer patients were included. Decreased preoperative absolute counts of peripheral lymphocyte subsets were correlated with advanced clinical stage. In multivariate analysis, independent predictive factors for prolonged hospital stay were age (p=0.04), decreased preoperative B cell counts (p=0.05), decreased preoperative NK cell counts (p=0.05) and complications (p<0.01). For postoperative complication, independent predictive factors were age (p=0.02), operation time (p=0.05), lymphocyte to C-reactive protein ratio (p=0.01) and decreased preoperative B cell counts (p=0.01). Conclusion: Our findings for the first time revealed that absolute counts of peripheral lymphocyte subsets are independent predictive factors for surgical outcomes in gastric cancer patients after D2 gastrectomy. We suggested that patients with impaired immune state should receive both preoperative immune modulator and nutritional support.

6.
Research (Wash D C) ; 2021: 9842391, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34806020

RESUMO

Electrochemical lithiation/delithiation of electrodes induces chemical strain cycling that causes fatigue and other harmful influences on lithium-ion batteries. In this work, a homemade in situ measurement device was used to characterize simultaneously chemical strain and nominal state of charge, especially residual chemical strain and residual nominal state of charge, in graphite-based electrodes at various temperatures. The measurements indicate that raising the testing temperature from 20°C to 60°C decreases the chemical strain at the same nominal state of charge during cycling, while residual chemical strain and residual nominal state of charge increase with the increase of temperature. Furthermore, a novel electrochemical-mechanical model is developed to evaluate quantitatively the chemical strain caused by a solid electrolyte interface (SEI) and the partial molar volume of Li in the SEI at different temperatures. The present study will definitely stimulate future investigations on the electro-chemo-mechanics coupling behaviors in lithium-ion batteries.

7.
Org Lett ; 23(20): 8067-8071, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34609887

RESUMO

An efficient copper-catalyzed cyclization of N-propargyl ynamides with borane adducts through B-H bond insertion has been developed. A series of valuable organoboron compounds are constructed in generally good yields with a wide substrate scope and good functional group tolerance under mild reaction conditions. Importantly, this protocol via vinyl cation intermediates constitutes a novel way of B-H bond insertion.

8.
PhytoKeys ; 181: 105-111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34611456

RESUMO

Vacciniummotuoense (Ericaceae), a new species from Motuo County, Xizang Autonomous Region, China is described and illustrated. This new species belongs to Vacciniumsect.Calcicolus and is morphologically most similar to V.dunalianum, but differs in having yellowish-brown tomentose young branches, petioles and inflorescence rachis, leaf blades with 2-3(-4) pairs of secondary veins, usually all basal and with fine veins impressed adaxially and urceolate to spherical corollas.

9.
ACS Synth Biol ; 10(11): 3084-3093, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34699187

RESUMO

Low expression levels and inflexible induction initiation have been the main obstacles to produce proteins using bacterial quorum sensing (QS). The typical QS system in Bacillus subtilis, ComQXPA, activates the promoter PsrfA using ComX and ComA as an auto-inducer and a promoter activator, respectively. Here, we developed a series of flexible autoinduction expression systems in B. subtilis WB600 based on ComQXPA using a super-folder green fluorescent protein as the reporter. The -35 region of PsrfA was replaced with corresponding conserved sequences of σA-dependent promoters, yielding P1 with 85% enhanced strength. We then applied a semi-rational design within the spacer between the -35 and -15 regions of P1 to generate the QS promoter PS1E, which generated 8.22-fold more expression than PsrfA. Based on PS1E, we finally obtained three types of autoinduction expression systems with initiation ranging from 1.5-9.5 h by optimizing the combination of the promoters for ComX and ComA. The yield of Bacillus deramificans pullulanase generated using autoinduction expression systems in B. subtilis reached 80.2 U/mL, which was 36% more than that of the most powerful constitutive promoter P566. Flexible autoinduction expression systems with diverse dynamic features have considerable potential for improving protein expression and metabolite production in B. subtilis.

10.
Indian J Radiol Imaging ; 31(2): 499-509, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34556940

RESUMO

Purpose Our case report presents the first case of suprasellar hemangioblastoma diagnosed preoperatively with dynamic computed tomography angiography (four-dimensional [4D] CTA) in a patient without Von Hippel-Lindau (VHL) disease. We illustrate the imaging characteristics of these exceedingly rare tumors and discuss the role of 4D CTA in confirming this diagnosis and guiding surgical management. Finally, we present a literature review of imaging findings, differential diagnosis, management, and prognosis. Case A 39-year-old woman known for diabetes mellitus type II and dyslipidemia presented with headache, bitemporal hemianopsia, and mild hyperprolactinemia. Initial diagnosis of suprasellar meningioma separate from pituitary gland was revised to definitive diagnosis of suprasellar hemangioblastoma after 4D CTA. Conclusion Suprasellar hemangioblastomas are extremely rare, often associated to VHL disease. They present as enhancing as suprasellar mass with prominent intra- and peritumoral vascular flow-voids on magnetic resonance imaging. 4D CTA confirms their vascular nature, demonstrates characteristic rapid shunting with feeding arteries, and enlarged draining veins, and is important in guiding surgical management.

11.
J Genet Genomics ; 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34538772

RESUMO

The origination of new genes contributes to the biological diversity of life. New genes may quickly build their network, exert important functions, and generate novel phenotypes. Dating gene age and inferring the origination mechanisms of new genes, like primate-specific genes, is the basis for the functional study of the genes. However, no comprehensive resource of gene age estimates across species is available. Here, we systematically date the age of 9,102,113 protein-coding genes from 565 species in the Ensembl and Ensembl Genomes databases, including 82 bacteria, 57 protists, 134 fungi, 58 plants, 56 metazoa, and 178 vertebrates, using a protein-family-based pipeline with Wagner parsimony algorithm. We also collect gene age estimate data from other studies and uniformly distribute the gene age estimates to time ranges in a million years for comparison across studies. All the data are cataloged into GenOrigin (http://genorigin.chenzxlab.cn/), a user-friendly new database of gene age estimates, where users can browse gene age estimates by species, age, and gene ontology. In GenOrigin, the information such as gene age estimates, annotation, gene ontology, ortholog, and paralog, as well as detailed gene presence/absence views for gene age inference based on the species tree with evolutionary timescale, is provided to researchers for exploring gene functions.

12.
Talanta ; 235: 122723, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517591

RESUMO

Tris(2,3-dibromopropyl) isocyanurate (TBC) is one of the novel brominated flame retardants that has been widely used in consumer goods. Humans may be exposed to TBC daily. Studies showed that TBC can induce significant toxicity. However, there is currently no report on its in situ localization in organs. In this study, we aimed to develop a reliable and reproductive method to determine the in situ localization of TBC in mouse organs by matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS). As commercially available matrices were not able to detect TBC in tissue section, we then developed a novel MALDI-IMS method based on 1,5-diaminonaphthalene hydrochloride and silver trifluoromethanesulfonate (NDA/AgOTf) as the matrix for the in situ localization of TBC. AgOTf used as the auxiliary matrix in the negative-ion mode showed an excellent MS signal of TBC. The detection limit of [2AgOTf + Br]- was at the µg/mL level. The developed MALDI-IMS method was successfully employed to obtain the TBC spatial distribution in the mouse organs collected from mice exposed to 160 mg/kg/day of TBC for 30 days. High-pressure liquid chromatography-tandem mass spectroscopy (HPLC-MS/MS) was also used to evaluate the accumulation of TBC in liver, kidney, heart, and brain. The combination of MALDI-IMS and HPLC-MS/MS showed that TBC can accumulate in mice organs and it is mainly distributed in the renal parenchyma. In summary, an innovative method was developed for the analysis of TBC spatial distribution by MALDI-IMS using a novel NDA/AgOTf matrix, extending the application of MALDI-IMS in environmental pollutants.


Assuntos
Poluentes Ambientais , Retardadores de Chama , Animais , Cromatografia Líquida de Alta Pressão , Poluentes Ambientais/análise , Camundongos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem
13.
World J Clin Cases ; 9(21): 5754-5768, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34368295

RESUMO

Extrahepatic metastasis (EHM) of hepatocellular carcinoma (HCC) has increasingly been seen due to improved survival with effective management of intrahepatic lesions. The presence of EHM indicates an advanced stage of HCC, for which systemic therapy serves as the standard treatment modality. Since the approval of Sorafenib as the first systemic agent in 2007, it took almost a decade to show its efficacy in both first and further lines of setting until the landscape of systemic drugs was finally expanded. Moreover, with inspiring results from immunotherapy trials in HCC, it appears that the introduction of immunotherapy may lead to an evolution in the portfolio of HCC treatment. Although the locoregional approach in the management of EHM is not recommended for advanced-stage HCC, efforts have been made to demonstrate its efficacy in symptom relief and potential benefit for overall survival. This review provides a summary of recent updates of the systemic agents in the treatment of advanced HCC, with an emphasis on aggressive locoregional management of EHM by various treatment modalities.

14.
Inorg Chem ; 60(17): 13021-13028, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34376047

RESUMO

Memristors with nonvolatile memory properties are expected to open the era of neuromorphic computing. However, it remains a huge challenge to develop memristors with high uniformity, high stability, and low power consumption for advanced synaptic bionics. Herein, an electroactive iridium(III) complex Ir-vio was designed and synthesized by incorporating a viologen moiety into its N∧N ligand. Complex Ir-vio showed multiple redox states and high sensitivity to an electrical stimulus. Importantly, two-terminal memristors with Ag/Ir-vio/W structure were successfully fabricated by the solution-processable method, which exhibited multilevel storage characteristics with a low switching threshold voltage of 0.5 V and high ON1/ON2/ON3/OFF current ratio of 105/103/102/1 at a low reading bias of 0.05 V. Moreover, the memristors can mimic synaptic plasticity, indicating that they can act as artificial synapses to construct brain-inspired neural networks. The memristive mechanisms can be ascribed to the interconversion among different charge-transfer and redox states under various electrical stimulus. To the best of our knowledge, this work is the first experimental demonstration of memristors based on iridium(III) complexes, opening a new era for the development of synaptic bionic devices based on organometallic compounds.

15.
PhytoKeys ; 180: 133-139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34408536

RESUMO

Agapetesheana Y. H. Tong & J. D. Ya (Ericaceae), a new species from Lüchun Xian, Yunnan Province, China is described and illustrated. This new species is assigned to Agapetessect.Agapetesser.Longifiles Airy Shaw. It is closest to A.inopinata Airy Shaw and A.oblonga Craib, but differs in having bead-like tubers, leaf blade with a wholly serrulate margin, subulate and much longer calyx lobes, much larger corollas that are carmine, green at the apex and maroon on angles, and longer stamens without spurs on the back.

16.
Medicine (Baltimore) ; 100(33): e26896, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34414945

RESUMO

PURPOSE: Obesity strongly affects the prognosis of various malignancies, including breast cancer. Leptin (LEP) may be associated with obesity and breast cancer prognosis. The purpose of our study was to determine the prognostic value of LEP in breast cancer. METHOD: We conducted a multi-omic analysis to determine the prognostic role of LEP. Different public bioinformatics platforms (Oncomine, Gene Expression Profiling Interactive Analysis, University of California Santa Cruz Xena, bc-GenExMiner, PrognoScan database, R2-Kaplan-Meier Scanner, UALCAN, Search Tool for the Retrieval of Interacting Genes/Proteins database , and The Database for Annotation, Visualization and Integrated Discovery) were used to evaluate the roles of LEP. Clinicopathological variables were evaluated. RESULTS: LEP was downregulated in breast cancer tissues compared to levels in normal tissues. By co-expressed gene analysis, a positive correlation between LEP and SLC19A3 was observed. Based on the clinicopathological analysis, low LEP expression was associated with older age, higher stage, lymph node status, human epidermal growth factor receptor 2 (HER2) status, estrogen receptor (ER+) positivity, and progesterone receptor (PR+) positivity. Kaplan-Meier survival analysis showed that low LEP expression indicated a poorer prognosis. LEP is hypermethylated in breast cancer tissues in PrognoScan and R2-Kaplan Meier Scanner, and low LEP expression was correlated with poor prognosis. LEP protein-protein interactions were analyzed using Search Tool for the Retrieval of Interacting Genes/Proteins database. Gene ontology analysis results showed that cellular component is mainly associated with the endosome lumen, cytosol, and secretory granules and is upregulated. For the biological process energy reserve, metabolic processes exhibited the greatest regulation compared to the others. In molecular function, it was mainly enriched in a variety of combinations, but hormone activity showed the highest regulation. CONCLUSION: Our study provides evidence for the prognostic role of LEP in breast cancer and as a novel potential therapeutic target in such malignancies. Nevertheless, further validation is required.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Leptina/genética , Neoplasias da Mama/mortalidade , Correlação de Dados , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
17.
Pancreatology ; 21(7): 1378-1385, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34429247

RESUMO

BACKGROUND: Glucose-regulated protein 78 (GRP78) plays an essential role in protein folding, transportation, and degradation, thus regulates ER homeostasis and promotes cell survival, proliferation and invasion. GRP78 expression in PDAC patients who received neoadjuvant therapy has not been reported. METHODS: This retrospective study of resected PDAC patients included 125 patients treated with neoadjuvant therapy (NAT) and 140 patients treated with surgery first (SF). The expression of GRP78 was evaluated by immunohistochemistry on tissue microarrays and the results were correlated with clinicopathologic parameters and survival. RESULTS: GRP78 expression was higher in SF patients compared to NAT patients (P < 0.001). In SF cohort, the median disease-free survival (DFS) and overall survival (OS) for patients with GRP78-positive tumors were 11.2 months and 25.0 months, respectively, compared to DFS of 52.1 months (P = 0.008) and OS of 69.5 months (P = 0.02) for those with GRP78-negative tumors. GRP78 expression correlated with higher frequency of recurrent/metastasis (P = 0.045). In NAT cohort, GRP78 expression correlated with shorter OS (P = 0.03), but not DFS (P = 0.08). GRP78 expression was an independent prognosticator for both DFS (P = 0.02) and OS (P = 0.049) in SF cohort and was an independent prognosticator for OS (P = 0.03), but not for DFS (P = 0.06) in NAT cohort by multivariate analysis. CONCLUSIONS: Our study showed that GRP78 expression in NAT cohort is lower than that in SF cohort. GRP78 expression correlated with shorter survival in both SF and NAT patients. Our findings suggest that targeting GRP78 may help to improve the prognosis in PDAC patients.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34304280

RESUMO

INTRODUCTION: More than 19% of patients undergoing knee arthroscopies suffers from articular cartilage defects. The chondral or osteochondral lesion has negative impacts on the knee joints function and the life quality of patients. However, the treatment remains challenging as hyaline cartilage is not renewable. The purpose of this study was to systematically analyze the data of randomized controlled trials for comparing the postoperative outcomes between osteochondral autologous transplantation (OAT) and microfracture (MF) procedure. We hypothesized that the outcomes were better in OAT than MF procedure. MATERIALS AND METHODS: A systematic literature search of the EMBASE, Pubmed, and Cochrane Library databases was conducted based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The outcome measures include: the rate of excellent or good results, the rate of return to sports, the failure rate, osteoarthritis rate, International Cartilage Repair Society (ICRS) score, Lysholm Knee Score, and Tegner scale. The statistical analysis was completed using Review Manager (RevMan, version 5.3) software. RESULTS: The systematic search identified 7 studies with a total of 346 patients. The pooled result showed significant differences between the two groups in the rate of return to sports and failure. The following outcome scores showed significant improvement (pre- vs postoperatively): Lysholm score (p = 0.02), Tegner scale (p < 0.00001), and ICRS score (p < 0.00001). The differences were not significant in the excellent or good results and the rate of osteoarthritis. CONCLUSION: The patients in OAT group may return to play quicker, even return to pre-injury level of activity compared to the MF group. OAT is better than MF procedure in accordance with Lysholm score, Tegner score, ICRS score, and the rate of failure. However, few studies have reported long-term outcomes and there has no uniform criteria for safe return to sports. Further research is needed. LEVEL OF EVIDENCE: Level II, meta-analysis of randomized controlled trials.

19.
Poult Sci ; 100(9): 101343, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34325110

RESUMO

Yeast culture plus enzymatically hydrolyzed yeast cell wall (YC-EHY) contains crude protein, mannan-oligosaccharide, ß-glucan and yeast culture. This study was carried out to explore the effects of dietary YC-EHY at different levels on growth performance, antioxidant capacity, and immune function of broiler chickens. A total of 320 one-day-age male broiler chicks were allocated into 4 groups and were fed with a basal diet supplemented with 0 mg/kg (the control group), 50 mg/kg, 100 mg/kg, 150 mg/kg YC-EHY for 42 d. Dietary YC-EHY improved average daily gain and feed efficiency during the starter, grower, and overall periods as well as average body weight of broiler chickens on 42 d (linear and quadratic, P < 0.05). Broiler chickens fed with YC-EHY quadratically increased jejunal sucrase activity on 21 d (quadratic, P < 0.05), and linearly and quadratically enhanced maltase activity on 21 and 42 d (linear and quadratic, P < 0.05). Supplementing YC-EHY linearly and quadratically enhanced jejunal superoxide dismutase (SOD) activity on 21 and 42 d and glutathione peroxidase (GPX) activity on 42 d whereas decreased malonaldehyde (MDA) concentration on 42 d (linear and quadratic, P < 0.05). Consistently, the jejunal genes expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and SOD1 on 21 and 42 d, heme oxygenase-1 (HO-1) and GPX1 on 42 d were enhanced by YC-EHY supplementation (linear and quadratic, P < 0.05). The concentrations of jejunal immunoglobulin G (IgG) on 21 and 42 d and secreted immunoglobulin A (SIgA) on 42 d were linearly and quadratically elevated by supplementing YC-EHY (linear and quadratic, P < 0.05). Dietary YC-EHY quadratically increased jejunal IgG and IgM genes expression on 21 d (quadratic, P < 0.05), and linearly and quadratically enhanced the genes expression of IgG and IgM on 42 d (linear and quadratic, P < 0.05). Overall, this study indicated that supplementing YC-EHY could exert beneficial effects on growth performance, intestinal antioxidant capacity and immune function in broiler chickens.


Assuntos
Antioxidantes , Galinhas , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Imunidade , Masculino , Saccharomyces cerevisiae
20.
J Exp Clin Cancer Res ; 40(1): 218, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193219

RESUMO

BACKGROUND: Liver cancer stem cells (LCSCs) play key roles in the metastasis, recurrence, and chemotherapeutic resistance of hepatocellular carcinoma (HCC). Our previous research showed that the POSTN gene is closely related to the malignant progression and poor prognosis of HCC. This study aimed to elucidate the role of POSTN in generating LCSCs and maintaining their stemness as well as the underlying mechanisms. METHODS: Human HCC tissues and matched adjacent normal tissues were obtained from 110 patients. Immunohistochemistry, western blotting (WB), and RT-PCR were performed to detect the expression of POSTN and stemness factors. The roles of transforming growth factor (TGF)-ß1 and AP-2α in the POSTN-induced stemness transformation of HCC cells were explored in vitro and in vivo using LCSCs obtained by CD133+ cell sorting. RESULTS: The high expression of POSTN was correlated with the expression of various stemness factors, particularly CD133, in our HCC patient cohort and in TCGA and ICGC datasets. Knockdown of POSTN expression decreased the abilities of HCC cell lines to form tumours in xenograft mouse models. Knockdown of POSTN expression also suppressed cell viability and clone formation, invasion, and sphere formation abilities in vitro. Knockdown of AP-2α attenuated the generation of CD133+ LCSCs and their malignant behaviours, indicating that AP-2α was a critical factor that mediated the POSTN-induced stemness transformation and maintenance of HCC cells. The role of AP-2α was verified by using a specific αvß3 antagonist, cilengitide, in vitro and in vivo. Activation of POSTN could release TGFß1 from the extracellular matrix and initiated POSTN/TGFß1 positive feedback signalling. Furthermore, we found that the combined use of cilengitide and lenvatinib suppressed the growth of HCC cells with high POSTN expression more effectively than the use of lenvatinib alone in the patient-derived xenograft (PDX) mouse model. CONCLUSIONS: The POSTN/TGFß1 positive feedback pathway regulates the expression of stemness factors and the malignant progression of HCC cells by regulating the transcriptional activation of AP-2α. This pathway may serve as a new target for targeted gene therapy in HCC.

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