1,080 research outputs found

    Dynamic changes of main metabolic substances during anther-derived embryos development in loquat (Eriobotrya japonica Lindl. cv. ‘Dawuxing’)

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    The main metabolic substances changes during the development process of anther-derived embryos in loquat (Eriobotrya japonica Lindl. cv. ‘Dawuxing’) were studied. These include water contents, dry mass contents, carbohydrates, soluble proteins and nucleic acids. In the developmental stages of anther-derived embryos, the fresh weight and the dry mass contents increased gradually with the anther-derived embryos development as a whole. Soluble sugars, soluble protein and nucleic acid were closely related to the development and maturation of embryos, changing significantly in metabolism at the important development turning points. Soluble sugar, fructose and starch contents had the same change trend. The two accumulation peaks appeared at globular and cotyledon stages. During the development of loquat anther embryos, the dynamics of protein synthesis were roughly in "S" shape. The two accumulation peaks appeared at globular and cotyledon stage, respectively, in accordance with the change of sugar and starch. Alkaline protein contents were higher than acidic protein contents. Alkaline protein contents and total soluble protein contents had the same change trend during the development process. DNA contents and total nucleic acid contents had the same change trend during the development of anther-derived embryos. The DNA synthesis peaks appeared at the embryogenic callus stage. RNA contents were very low at embryogenic callus stage and cotyledon stage, while DNA was actively synthesized at the two stages.Key words: Eriobotrya japonica, anther culture, embryos, metabolic substances

    Development and evaluation of pH-responsive single-walled carbon nanotube-doxorubicin complexes in cancer cells

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    Single-walled carbon nanotubes (SWNTs) have been identified as an efficient drug carrier. Here a controlled drug-delivery system based on SWNTs coated with doxorubicin (DOX) through hydrazone bonds was developed, because the hydrazone bond is more sensitive to tumor microenvironments than other covalent linkers. The SWNTs were firstly stabilized with polyethylene glycol (H2N-PEG-NH2). Hydrazinobenzoic acid (HBA) was then covalently attached on SWNTs via carbodiimide-activated coupling reaction to form hydrazine-modified SWNTs. The anticancer drug DOX was conjugated to the HBA segments of SWNT using hydrazine as the linker. The resulting hydrazone bonds formed between the DOX molecules and the HBA segments of SWNTs are acid cleavable, thereby providing a strong pH-responsive drug release, which may facilitate effective DOX release near the acidic tumor microenvironment and thus reduce its overall systemic toxicity. The DOX-loaded SWNTs were efficiently taken up by HepG2 tumor cells, and DOX was released intracellularly, as revealed by MTT assay and confocal microscope observations. Compared with SWNT-DOX conjugate formed by supramolecular interaction, the SWNT-HBA-DOX featured high weight loading and prolonged release of DOX, and thus improved its cytotoxicity against cancer cells. This study suggests that while SWNTs have great potential as a drug carrier, the efficient formulation strategy requires further study

    Higgs algebraic symmetry of screened system in a spherical geometry

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    The orbits and the dynamical symmetries for the screened Coulomb potentials and isotropic harmonic oscillators have been studied by Wu and Zeng [Z. B. Wu and J. Y. Zeng, Phys. Rev. A 62,032509 (2000)]. We find the similar properties in the responding systems in a spherical space, whose dynamical symmetries are described by Higgs Algebra. There exists a conserved aphelion and perihelion vector, which, together with angular momentum, constitute the generators of the geometrical symmetry group at the aphelia and perihelia points (r˙=0)(\dot{r}=0).Comment: 8 pages, 1 fi

    The role of globular heads of the C1q receptor in HPV 16 E2-induced human cervical squamous carcinoma cell apoptosis is associated with p38 MAPK/JNK activation

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    BACKGROUND Human papillomavirus type 16 (HPV 16) E2 protein is a multifunctional DNA-binding protein. HPV 16 E2 regulates many biological responses, including DNA replication, gene expression, and apoptosis. The purpose of this study was to investigate the relationship among the receptor for globular heads of the human C1q (gC1qR) gene expression, HPV 16 E2 transfection and apoptosis regulation in human cervical squamous carcinoma cells (C33a and SiHa). METHODS gC1qR expression was examined in C33a and SiHa cells using real-time PCR and Western blot analysis. Apoptosis of C33a and SiHa cells was assessed by flow cytometry. C33a and SiHa cell viability, migration and proliferation were detected using the water-soluble tetrazolium salt (WST-1) assay, a transwell assay and 3H-thymidine incorporation into DNA (3H-TdR), respectively. RESULTS C33a and SiHa cells that were transfected with a vector encoding HPV 16 E2 displayed significantly increased gC1qR gene expression and p38 mitogen-activated protein kinase (p38 MAPK)/c-jun N-terminal kinase (JNK) activation as well as up-regulation of cellular apoptosis, which was abrogated by the addition of gC1qR small interfering RNA (siRNA). Furthermore, the changes in C33a and SiHa cell viability, migration and proliferation that were observed upon HPV 16 E2 transfection were abrogated by SB203580 (a p38 MAPK inhibitor) or SP600125 (a JNK inhibitor) treatment. CONCLUSION These data support a mechanism whereby HPV 16 E2 induces apoptosis by silencing the gC1qR gene or inhibiting p38 MAPK/JNK signalling in cervical squamous cell carcinoma.This study was supported by grants from the National Natural Science Foundation of China (No. 81000251) and the Nanjing Medical Science and Technique Development Foundation

    Individualized analysis reveals CpG sites with methylation aberrations in almost all lung adenocarcinoma tissues

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    Additional file 1: Table S1. Stable and reversal CpG site pairs identified in the samples measured by two platforms

    Broad-Spectrum Antimicrobial Epiphytic and Endophytic Fungi from Marine Organisms: Isolation, Bioassay and Taxonomy

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    In the search for new marine derived antibiotics, 43 epi- and endophytic fungal strains were isolated from the surface or the inner tissue of different marine plants and invertebrates. Through preliminary and secondary screening, 10 of them were found to be able to produce broad-spectrum antimicrobial metabolites. By morphological and molecular biological methods, three active strains were characterized to be Penicillium glabrum, Fusarium oxysporum, and Alternaria alternata

    An adolescent with primary cutaneous follicle center lymphoma: a case report and literature review

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    Primary cutaneous follicle center lymphoma (PCFCL) differs from follicular lymphoma in biological behavior and molecular profile and is treated as a distinct entity, according to the 5th edition of the World Health Organization classification of hematolymphoid tumors. It is an uncommon cutaneous B-cell lymphoma that is considerably rare in children and adolescents. To date, only 13 cases of individuals younger than 20 years of age have been reported in the literature. The lack of relevant clinical epidemiological data in this population has hampered the investigation of its clinical and diagnostic aspects. Here we report the case of a 17-year-old male with PCFCL, who may be the first PCFCL patient under 20 years of age reported in China. He was admitted to the hospital with a solitary nodule on his face. After complete surgical excision, the patient’s facial mass was histologically identified as PCFCL. The patient’s prognosis was favorable, with no recurrence at 17 months of follow-up after the surgical resection. We present a case of an adolescent PCFCL patient and systematically review the literature with a view to increase the awareness of the disease and inform the diagnosis and treatment of this age group

    Novel norcantharidin-loaded liver targeting chitosan nanoparticles to enhance intestinal absorption

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    In this paper, two novel liver-targeting nanoparticles, norcantharidin-loaded chitosan nanoparticles (NCTD-CS-NPs) and norcantharidin-associated galactosylated chitosan nanoparticles (NCTD-GC-NPs), were prepared using ionic cross-linkage. The physical properties, particle size, encapsulation efficiency, and drug release characteristics of the nanoparticles were investigated in vitro. To investigate the intestinal absorption mechanisms of the two preparations, a series of experiments was carried out, including in situ circulation method, in vitro everted gut sacs, and Ussing chamber perfusion technique. The absorption rate constants (Ka) of NCTD at different segments were found to be duodenum > jejunum > ileum > colon. The concentration had no distinctive effect on absorption kinetics, suggesting that drug absorption is not dose-dependent. The transport of NCTD was found to be inhibited by P-glycoprotein (P-gp) inhibitor, indicating that NCTD might be the substrate of P-gp. The order of the absorption enhancer effects were as follows: low molecular weight chitosan (CS-8kDa) > high molecular weight chitosan (CS-30kDa) > Poloxamer > sodium dodecyl sulfate (SDS) > sodium deoxycholate (SDCh). The results indicate that the chitosan nanoparticles can improve intestinal absorption of NCTD

    A kognitív készségek rendszere és fejlődése

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    Additional file 7: Figure S1. The KEGG pathways separately enriched with hypermethylated (a) and hypomethylated (b) genes in at least 10% of the 539 TCGA lung adenocarcinoma samples
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