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1.
Plant Physiol Biochem ; 153: 30-39, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32474384

RESUMO

High temperatures limit the successful cultivation of the Hylocereus species on a global basis. We aimed to investigate the degree of heat tolerance in three species, namely, the diploids Hylocereus undatus and H. monacanthus, and the tetraploid H. megalanthus, and nine of their interspecific-interploid hybrids. Rooted cuttings were exposed to heat stress (45/35 °C) or control conditions (25/20 °C) for eight days. Initially, the plants were screened for their tolerance to heat stress and ranked into four heat tolerance categories: good tolerance, moderate tolerance, low tolerance, or sensitive, according to the decrease in the maximum quantum efficiency of photosystem II (Fv/Fm) and visual stem damage. The physiological and biochemical performances of the parental species and of three hybrids representing three different heat-tolerance categories were further analyzed in depth. H. megalanthus (classified as heat sensitive) showed a 65% decrease in Fv/Fm and severe visual stem damage, along with a marked reduction in total chlorophyll content, a large increase in malondialdehyde, and inhibition of catalase activity. H. undatus and H. monacanthus, (classified as low-tolerance species) exhibited slight stem "liquification." The good-tolerance hybrid Z-16 exhibited the best performance under heat stress (21% decrease in Fv/Fm) and the absence of stem damage, coupled with a small decrease in total chlorophyll content, a slight increase in malondialdehyde, high antioxidant activity, and proline accumulation progressing with time. Our findings revealed that most of the hybrids performed better than their parental species, indicating that our breeding programs can provide Hylocereus cultivars suitable for cultivation in heat-challenging regions.


Assuntos
Cactaceae/fisiologia , Temperatura Alta , Estresse Fisiológico , Clorofila/análise , Complexo de Proteína do Fotossistema II/fisiologia , Melhoramento Vegetal
2.
J Nanosci Nanotechnol ; 16(4): 3816-20, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27451716

RESUMO

Doped and undoped ZnS colloidal nanocrystals have drawn much attention due to their versatile applications in the fields of optoelectronics and biotechnology. In this paper, Cu doped ZnS quantum dots were synthesized via the simple thermolysis of ethylxanthate salts. The lattice and optical properties of the nanocrystals were then studied in detail. The quantum dot lattice contracted linearly between Cu concentrations of 0.2-2%, while it continued to contract more gradually as Cu concentrations were further increased from 4 to 6%, due in part to the Cu ions located on the surface of the ZnS lattice. Cu incorporation induces a long tail in absorption at long wavelengths. The PL spectrum shows a red shift at first, and then a blue shift with increases in Cu concentration. Cu doped at low concentrations (0.2-1%) enhanced the emission, while high Cu concentrations (2-6%) quenched emissions.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-382861

RESUMO

Objective To explore the mechanism of immunomodulatory activity of triptolide on healthy volunteers peripheral blood mononuclear cells (PBMC)-derived plasmacytoid dendritic cells (pDCs). Methods Healthy volunteers-derived pDCs were sorted by flow cytometry, then incubated with triptolide (0, 5, 10, 30 μg/L). After 24 hours, we detected the concentration of IFN-α, IL-6, TNF-α using ELISA. After 5 days, the cultrural cells were collected and analyzed by flow cytometry, light microscope and electron microscope scanning. Results Triptolide-treated pDCs secreted lower level of IFN-α,IL-6 ,TNF-α, triptolide could inhibit pDCs differentiation to DCs which displayed more immature morphology and immunophenotypes than untreated-pDCs. Conclusion Triptolide could decrease the immune function of pDCs, inhibit differentiation and maturation of pDCs.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-419867

RESUMO

Objective To explore the mechanism of immunomodulatory activity of triptolide on systemic lupus erythematosus(SLE) patients peripheral blood mononuclear cells( PBMC)-derived dendritic cells (DCs).Methods SLE -derived DCs were sorted by flow cytometry from peripheral blood mononuclear cells,then incubated with triptolide (0,5,10,30 μg/L ).After 24 h,we collected the supernatants and then detected the concentration of IFN-α,IL-6,TNF-α using ELISA.After 5 d,the cultrural cells were collected and CD11c,CD80,CD86 expression of DCs were analyzed by flow cytometry,we observed the morphology of DC by light microscope and electron microscope scanning.Results Triptolide -treated DCs from SLE patients with active and stable disease secreted lower level of IFN-α,IL-6,TNF-α,triptolide could inhibit DCs differentiation,which displayed more immature morphology and immunophenotypes than untreatedDCs.Conclusion Triptolide could decrease the immune function of DCs from SLE,inhibit differentiation and maturation of DCs.

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-548876

RESUMO

Objective:To explore the mechanism for immunomodulatory activity of Astragalus polysaccharide (APS) with peripheral blood mononuclear cells(PBMC)-derived plasmacytoid dendritic cells (pDCs) from healthy volunteers.Methods:Healthy volunteers-derived pDCs were sorted by flow cytometry,then incubated with APS (0m50,100,200 mg/L ).After 24 hours,the concentration of IFN-?,TNF-?,IL-6 was detected using ELISA.After 5 days,the cultured cells were collected and analyzed by flow cytometry,light microscope and electron microscope scanning.Results:APS-treated pDCs secreted higher level of IFN-?,TNF-?,IL-6.APS could promote differentiation of pDCs to dendritic cells (DCs) which displayed more matured morphology and immunophenotypes compared to the untreated-pDCs.Conclusion:APS could increase the immune function of pDCs,promote differentiation and maturation of pDCs.

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