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1.
Int J Mol Sci ; 24(13)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37446217

RESUMO

Dendrobium (Orchidaceae, Epidendoideae) plants have flowers with a wide variety of colors that persist for a long period throughout the year. The yellow coloration of Dendrobium flowers is mainly determined by the flavonol pathway and the flavone pathway, but the relevant biosynthesis mechanisms during vernalization remain unclear. To explore the similarities and differences in flavonoid biosynthesis in different tissues during vernalization, we selected two species of Dendrobium for a flower color study: Dendrobium capillipes Rchb (which has yellow flowers) and Dendrobium nobile Lindl (which has white flowers). We collected a total of 36 samples from six tissue types and both Dendrobium species during vernalization and subjected the samples to metabolic profiling and transcriptome sequencing. A total of 31,504 differentially expressed genes (DEGs) were identified between different tissues of the two Dendrobium species by transcriptomic analysis. However, many differentially accumulated metabolites (DAMs) and DEGs were enriched not only in the general pathway of "flavonoid biosynthesis" but also in multiple subpathways of "flavone and flavonol biosynthesis". According to a combined transcriptome and metabolome analysis, Putrescine hydroxycinnamoyl transferase 1 (LOC110093422) may be the main gene responsible for the differences in flavonoid accumulation during vernalization, which is closely associated with yellow flowers. Taken together, the results of our study preliminarily revealed the metabolites responsible for and the key genes regulating flavonoid biosynthesis during vernalization. These results provide a basis for the further study of the molecular mechanism of flavonoid synthesis during vernalization.


Assuntos
Dendrobium , Flavonas , Transcriptoma , Flavonoides/metabolismo , Dendrobium/genética , Dendrobium/metabolismo , Perfilação da Expressão Gênica/métodos , Flavonóis , Regulação da Expressão Gênica de Plantas
2.
Anal Biochem ; 655: 114869, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35988798

RESUMO

A novel, simple and efficient capillary electrophoresis method was developed to simultaneous determination of six furanocoumarins (psoralen, isopsoralen, imperatorin, isoimperatorin, phellopterin, and cnidilin). The separation buffer consisted of 30 mM boric acid, 12 mM sulfobutylether-ß-cyclodextrin and 1.5 mM 2-hydroxypropyl-ß-cyclodextrin (pH 7.8); the voltage was 20 kV, the temperature was 25 °C and the detection wavelength was at 246 nm with a diode array detector (DAD). Under the above conditions, the analytes could be separated with high resolution in less than 7 min. This method was used to simultaneously determine the content of psoralen, imperatorin, isoimperatorin and phellopterin in Angelica Dahurica Radix. And good linearities were obtained with correlation coefficients from 0.9992 to 0.9999. The limits of detection (LOD, S/N = 3) and the limits of quantitation (LOQ, S/N = 10) ranged from 0.6 to 3.0 µg/mL and from 2.1 to 9.9 µg/mL, respectively. The recoveries ranged between 98.8% and 101.8%. The results indicated the method can achieve baseline separation and quantitative analysis of furanocoumarins in Chinese herbal medicines and formulations.


Assuntos
Angelica , Medicamentos de Ervas Chinesas , Furocumarinas , Angelica/química , Medicamentos de Ervas Chinesas/química , Eletroforese Capilar , Furocumarinas/análise , Furocumarinas/química , Raízes de Plantas/química
3.
J Sep Sci ; 45(16): 3197-3207, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35772030

RESUMO

A simple, comprehensive, and efficient capillary electrophoresis method using a self-synthesized ionic liquid [N-methylimidazole-ß-cyclodextrin] [bromide] as a separation selector was developed for the simultaneous separation and determination of five chlorogenic acid isomers (chlorogenic acid, cryptochlorogenic acid, neochlorogenic acid, isochlorogenic acid A, isochlorogenic acid B). After optimization of separation conditions, the electrolyte solution was 50 mM ammonium acetate buffer containing 0.7% (w/w) ionic liquid [N-methylimidazole-ß-cyclodextrin] [bromide] (pH 4.8), 15 kV of the electric field was applied at 25°C, and the detection wavelength was at 237 nm. Under the optimal separation conditions, good linearities were obtained with linear correlation coefficients of the five analytes of 0.9994-0.9998, and the limits of detection and the limits of quantification were 0.6-2.8 and 2.2-9.5 µg/ml. Excellent accuracy and precision were obtained for the five analytes. The intraday and interday precision of standards ranged from 0.5 to 1.3% and from 1.2 to 1.9%. The intraday and interday precision of samples ranged from 1.0 to 1.9% and from 1.2 to 2.6%. The sample recovery rates were between 98.0 and 101.8%. This method was successfully applied for the analysis of five components in Honeysuckle Chinese medicinal preparations. The mechanisms involved in the separation of five analytes by [N-methylimidazole-ß-cyclodextrin] [bromide] were discussed.


Assuntos
Líquidos Iônicos , Lonicera , beta-Ciclodextrinas , Brometos , Ácido Clorogênico , Eletroforese Capilar , Imidazóis , Estereoisomerismo
4.
Anal Chem ; 90(8): 5496-5502, 2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29611421

RESUMO

Hydrogen sulfide is a highly toxic molecule to human health, but high-performance detection of it remains a challenge. Herein, we report an ultrasensitive photoelectrochemical (PEC) sensor for H2S by modifying indium tin oxide (ITO) electrodes with Cd2+-doped amorphous TiO2 hollow spheres, which are prepared by templating against colloidal silica particles followed by a cadmium-sodium cation exchange reaction. The amorphous TiO2 hollow spheres act as both the probing cation carrier and the photoelectric beacon. Upon exposure to sulfide ions, the photocurrent of the functionalized photoanode proportionately decreases in response to the formation of CdS nanoparticles. The decreased photocurrent could be attributed to the mismatching bandgap between the amorphous TiO2 and CdS nanoparticles: the photoexcited electrons and holes from amorphous TiO2 are transferred to the conduction band and valence band of CdS, respectively, and then recombined. The decrease in photocurrent is linear with the concentration of sulfide ions in the range from 1 to 10 000 pmol L-1 with a detection limit of 0.36 pmol L-1. Enabled by a unique sensitization mechanism, this PEC sensor features excellent performance in a wide linear range, high selectivity and sensitivity, high stability, and low fabrication cost.

5.
Heliyon ; 10(1): e23446, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38163137

RESUMO

Background: Endoscopic nipple-sparing mastectomy (E-NSM) is a promising procedure in the treatment of breast cancer, but the limitations of endoscopic tools and intrinsic technical complexity of the technique hinder its applicability. Here, we introduce a novel surgery, gasless endoscopic transaxillary subcutaneous mastectomy and immediate reconstruction with implants (GETSMIRI), for breast cancer. and early effects. Methods: A retrospective analysis of the clinical data of 11 female patients, aged 50 (27-78) years, admitted to our hospital from January to December 2022, who underwent gasless endoscopic transaxillary subcutaneous mastectomy and immediate reconstruction with implants (GETSMIRI), was conducted. This study was designed to assess patient satisfaction before and after breast reconstruction, early complications, and breast function. Results: The tumors were all solitary, with a mean maximum diameter of 1.0 (0-2.0) cm and a mean distance of 2.3 (2-4) cm from the nipple, the mean intraoperative bleeding volume was 47.5 mL, and the mean hospital stay was 1.5 d. Postoperatively, 1 patient developed depigmentation of the nipple due to mild ischemia. There were no incisional complications, subcutaneous emphysema, infection, areola necrosis, skin flap necrosis, or removal of the prosthesis and/or patch. No tumor recurrence or metastasis was observed during the follow-up period. The difference between breast satisfaction and psychosocial health scores was not statistically significant (P = 0.680; P = 0.612). Conclusion: GETSMIRI, immediate implantable breast reconstruction, is less invasive than other such procedures, and short-term follow-up results show good postoperative satisfaction, making it an alternative surgical method.

6.
Polymers (Basel) ; 16(4)2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38399876

RESUMO

In recent years, the incidence of bone defects has been increasing year by year. Bone transplantation has become the most needed surgery after a blood transfusion and shows a rising trend. Three-dimensional-printed implants can be arbitrarily shaped according to the defects of tissues and organs to achieve perfect morphological repair, opening a new way for non-traumatic repair and functional reconstruction. In this paper, strontium-doped mineralized collagen was first prepared by an in vitro biomimetic mineralization method and then polylactic acid was homogeneously blended with the mineralized collagen to produce a comprehensive bone repair scaffold by a gas extrusion 3D printing method. Characterization through scanning electron microscopy, X-ray diffraction, and mechanical testing revealed that the strontium-functionalized composite scaffold exhibits an inorganic composition and nanostructure akin to those of human bone tissue. The scaffold possesses uniformly distributed and interconnected pores, with a compressive strength reaching 21.04 MPa. The strontium doping in the mineralized collagen improved the biocompatibility of the scaffold and inhibited the differentiation of osteoclasts to promote bone regeneration. This innovative composite scaffold holds significant promise in the field of bone tissue engineering, providing a forward-thinking solution for prospective bone injury repair.

7.
Polymers (Basel) ; 16(16)2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39204550

RESUMO

The mass production of uniform, high-quality polymer nanofibers remains a challenge. To enhance spinning yield, a multi-string standing wave electrospinning apparatus was developed by incorporating a string array into a standing wave electrospinning device. The process parameters such as string spacing, quantity, and phase difference were optimized, and their effects on the electric field distribution within the spinning area were analyzed using electric field simulations. When the string spacing was less than 40 mm or the number of strings exceeded two, the electric field strength significantly decreased due to electric field interference. However, this interference could be effectively mitigated by setting the string standing wave phase difference to half a period. The optimal string array parameters were identified as string spacing of 40 mm, two strings, and a phase difference of half a period. Multi-string standing wave electrospinning produced fibers with diameters similar to those obtained with single-string standing wave electrospinning (178 ± 72 nm vs. 173 ± 48 nm), but the yield increased by 88.7%, reaching 2.17 g/h, thereby demonstrating the potential for the large-scale production of nanofibers. This work further refined the standing wave electrospinning process and provided valuable insights for optimizing wire-type electrospinning processes.

8.
Neurosci Bull ; 40(1): 35-49, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37608137

RESUMO

Acute hypobaric hypoxic brain damage is a potentially fatal high-altitude sickness. Autophagy plays a critical role in ischemic brain injury, but its role in hypobaric hypoxia (HH) remains unknown. Here we used an HH chamber to demonstrate that acute HH exposure impairs autophagic activity in both the early and late stages of the mouse brain, and is partially responsible for HH-induced oxidative stress, neuronal loss, and brain damage. The autophagic agonist rapamycin only promotes the initiation of autophagy. By proteome analysis, a screen showed that protein dynamin2 (DNM2) potentially regulates autophagic flux. Overexpression of DNM2 significantly increased the formation of autolysosomes, thus maintaining autophagic flux in combination with rapamycin. Furthermore, the enhancement of autophagic activity attenuated oxidative stress and neurological deficits after HH exposure. These results contribute to evidence supporting the conclusion that DNM2-mediated autophagic flux represents a new therapeutic target in HH-induced brain damage.


Assuntos
Hipóxia , Estresse Oxidativo , Camundongos , Animais , Autofagia , Cognição , Sirolimo/uso terapêutico
9.
Redox Biol ; 69: 102983, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38064762

RESUMO

Shank3, a key molecule related to the development and deterioration of autism, has recently been found to downregulate in the murine brain after ischemia/reperfusion (I/R). Despite this discovery, however, its effects on neuronal injury and the mechanism underlying the effects remain to be clarified. To address this, in this study, based on genetically modified mice models, we revealed that the expression of Shank3 showed a time-dependent change in murine hippocampal neurons after I/R, and that conditional knockout (cko) of Shank3 in neurons resulted in aggravated neuronal injuries. The protective effects of Shank3 against oxidative stress and inflammation after I/R were achieved through direct binding STIM1 and subsequent proteasome-mediated degradation of STIM1. The STIM1 downregulation induced the phosphorylation of downstream Nrf2 Ser40, which subsequently translocated to the nucleus, and further increased the expression of antioxidant genes such as NQO1 and HO-1 in HT22 cells. In vivo, the study has further confirmed that double knockout of Shank3 and Stim1 alleviated oxidative stress and inflammation after I/R in Shank3cko mice. In conclusion, the present study has demonstrated that Shank3 interacts with STIM1 and inhibits post-I/R neuronal oxidative stress and inflammatory response via the Nrf2 pathway. This interaction can potentially contribute to the development of a promising method for I/R treatment.


Assuntos
Isquemia Encefálica , Traumatismo por Reperfusão , Camundongos , Animais , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Estresse Oxidativo , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Inflamação/genética , Inflamação/metabolismo , Reperfusão , Neurônios/metabolismo , Apoptose , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/farmacologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo
10.
Antiviral Res ; 230: 105974, 2024 10.
Artigo em Inglês | MEDLINE | ID: mdl-39089331

RESUMO

The outbreak of 2022 monkeypox virus (MPXV) infection in nonendemic regions is a global public health concern. A highly effective and safe MPXV vaccine that is available to the general public is urgently needed to control the mpox pandemic. Here, we developed a multivalent mRNA vaccine candidate, MPXV-1103, which expresses the full-length B6, A35, A29 and M1 proteins with three flexible linkers (G4S1)3 in a single sequence. Compared with the monovalent MPXV mRNA vaccine candidates or the quadrivalent mRNA vaccine from mixtures of the four monovalent MPXV mRNA vaccines, MPXV-1103 elicits a robust humoral response and an MPXV-specific T-cell response and protects mice from lethal vaccinia virus (VACV) challenge, with no live virus detected in the nasal or lungs even at dosages as low as 1 µg. Furthermore, analysis of complete blood counts and photomicrographs of tissue from the main organs of mice vaccinated with MPXV-1103 at doses of 5 µg and 20 µg revealed that two doses of MPXV-1103 did not cause any observable pathological changes in the mice. Collectively, our results suggest that MPXV-1103, with features of high efficacy, safety and a simplified manufacturing process, is a promising vaccine candidate for defending against MPXV infection.


Assuntos
Anticorpos Antivirais , Camundongos Endogâmicos BALB C , Vaccinia virus , Vacinas de mRNA , Animais , Camundongos , Vaccinia virus/imunologia , Vaccinia virus/genética , Feminino , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Vacínia/prevenção & controle , Vacínia/imunologia , Mpox/prevenção & controle , Mpox/imunologia , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Monkeypox virus/imunologia , Linfócitos T/imunologia , Imunidade Humoral
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