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1.
Micromachines (Basel) ; 15(5)2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38793200

RESUMO

Ultra-thin vapor chambers (UTVCs) are widely used to cool high-power electronics due to their excellent thermal conductivity. In this study, a UTVC of 82 mm × 58 mm × 0.39 mm with composite wick was prepared. The composite wick is composed of two layers of copper mesh and multiple spiral-woven meshes (SWMs), and the composite wick was applied in UTVC to improve liquid replenishment performance and temperature uniformity. Furthermore, the thermal performance of UTVCs with different support column diameters, filling ratios (FRs), and SWM structures was experimentally studied. The results found that the equivalent thermal conductivity (ETC) decreases as the diameter of the support column increases; the UTVC with 0.5 mm support column diameter has the highest ETC, at 3473 W/(m·K). Then, the effect of FR on the heat transfer performance of UTVCs with SWM numbers of 0, 1, 2, and 3 (0 SWMs, 1 SWM, 2 SWMs, 3 SWMs) is consistent, the 30% FR UTVC with 3 SWMs having the highest ETC, at 3837 W/(m·K). Finally, the increased number of SWMs can significantly improve the ultimate power of the UTVCs, the UTVC with 3 SWMs having the highest ultimate power, at 26 W. The above experimental studies indicate that the designed and manufactured UTVCs have great potential advantages in thermal dissipation for electronics.

2.
Front Genet ; 12: 680457, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539731

RESUMO

The Na+/H+ exchangers (NHXs) are a class of transporters involved in ion balance during plant growth and abiotic stress. We performed systematic bioinformatic identification and expression-characteristic analysis of CaNHX genes in pepper to provide a theoretical basis for pepper breeding and practical production. At the whole-genome level, the members of the CaNHX gene family of cultivated and wild pepper were systematically identified using bioinformatics methods. Sequence alignment and phylogenetic tree construction were performed using MEGA X software, and the gene functional domain, conserved motif, and gene structure were analyzed and visualized. At the same time, the co-expression network of CaNHX genes was analyzed, and salt-stress analysis and fluorescence quantitative verification of the Zunla-1 cultivar under stress conditions were performed. A total of 9 CaNHX genes were identified, which have typical functional domains of the Na+/H+ exchanger gene. The physical and chemical properties of the protein showed that the protein was hydrophilic, with a size of 503-1146 amino acids. Analysis of the gene structure showed that Chr08 was the most localized chromosome, with 8-24 exons. Cis-acting element analysis showed that it mainly contains cis-acting elements such as light response, salicylic acid response, defense, and stress response. Transcriptom and co-expression network analysis showed that under stress, the co-expressed genes of CaNHX genes in roots and leaves were more obvious than those in the control group, including ABA, IAA, and salt. The transcriptome and co-expression were verified by qRT-PCR. In this study, the CaNHX genes were identified at the genome level of pepper, which provides a theoretical foundation for improving the stress resistance, production, development, and utilization of pepper in genetic breeding.

3.
BMC Gastroenterol ; 19(1): 151, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31443637

RESUMO

BACKGROUND: With the development and application of endoscopic technology, most pedunculated polyps can be absolutely resected with a complete specimen by hot snare polypectomy (HSP). Brunner's gland hamartoma (BGH) is a rare benign small bowel tumor. The majority of BGH measuring about 2 cm in diameter, rarely larger than 5 cm. Most patients are asymptomatic, some may present with gastrointestinal hemorrhage or intestinal obstruction. Symptomatic larger lesions leading to bleeding or obstruction should be excised either endoscopically or surgically. Whether it is safe and effective that removing a BGH measuring about 7 cm by HSP is not known. CASE PRESENTATION: Here, we reported a rare case of a proximal duodenum pedunculated mass measuring about 7 cm which was responsible for the patient's severe anemia. we treated it as a pedunculated polyp. After being pretreated the stalk with an endoloop which was placed around the base of the mass to prevent post-polypectomy bleeding (PPB), the pedunculated BGH was removed by HSP completely. The stalk of the mass was negative. We achieved a curative resection. CONCLUSION: It is a safe and effective for our patient to treat the pedunculated BGH measuring about 7 cm as a pedunculated polyp and remove it by HSP. And future prospective studies in larger cohorts are needed to confirm it.


Assuntos
Glândulas Duodenais/patologia , Duodenopatias , Endoscopia/métodos , Hamartoma , Pólipos Intestinais , Dissecação/métodos , Duodenopatias/patologia , Duodenopatias/fisiopatologia , Duodenopatias/cirurgia , Feminino , Hamartoma/patologia , Hamartoma/fisiopatologia , Hamartoma/cirurgia , Humanos , Pólipos Intestinais/patologia , Pólipos Intestinais/fisiopatologia , Pólipos Intestinais/cirurgia , Pessoa de Meia-Idade , Resultado do Tratamento , Carga Tumoral
4.
J Nanobiotechnology ; 16(1): 76, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30290822

RESUMO

BACKGROUND: Recently, we found that berberine (BBR) exerts anti-acute myeloid leukemia activity, particularly toward high-risk and relapsed/refractory acute myeloid leukemia MV4-11 cells in vitro. However, the poor water solubility and low bioavailability observed with oral BBR administration has limited its clinical use. Therefore, we design and develop a novel oil-in-water self-nanoemulsifying system for BBR (BBR SNE) to improve oral bioavailability and enhance BBR efficacy against acute myeloid leukemia by greatly improving its solubility. RESULTS: This system (size 23.50 ± 1.67 nm, zeta potential - 3.35 ± 0.03 mV) was prepared with RH40 (surfactant), 1,2-propanediol (co-surfactant), squalene (oil) and BBR using low-energy emulsification methods. The system loaded BBR successfully according to thermal gravimetric, differential scanning calorimetry, and Fourier transform infrared spectroscopy analyses. The release profile results showed that BBR SNE released BBR more slowly than BBR solution. The relative oral bioavailability of this novel system in rabbits was significantly enhanced by 3.41-fold over that of BBR. Furthermore, Caco-2 cell monolayer transport studies showed that this system could help enhance permeation and prevent efflux of BBR. Importantly, mice with BBR SNE treatment had significantly longer survival time than BBR-treated mice (P < 0.001) in an MV4-11 engrafted leukemia murine model. CONCLUSIONS: These studies confirmed that BBR SNE is a promising therapy for acute myeloid leukemia.


Assuntos
Absorção Fisiológica , Berberina/uso terapêutico , Emulsões/química , Leucemia Mieloide Aguda/tratamento farmacológico , Nanopartículas/química , Administração Oral , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Berberina/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citarabina/farmacologia , Citarabina/uso terapêutico , Interações Medicamentosas , Liberação Controlada de Fármacos , Leucemia Mieloide Aguda/patologia , Camundongos , Nanopartículas/ultraestrutura , Permeabilidade , Transição de Fase , Coelhos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Plant Cell Rep ; 36(9): 1375-1385, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28577237

RESUMO

KEY MESSAGE: Insertion of a solo LTR, which possesses strong bidirectional, stem-specific promoter activities, is associated with the evolution of a dwarfing apple spur mutation. Spur mutations in apple scions revolutionized global apple production. Since long terminal repeat (LTR) retrotransposons are tightly related to natural mutations, inter-retrotransposon-amplified polymorphism technique and genome walking were used to find sequences in the apple genome based on these LTRs. In 'Red Delicious' spur mutants, a novel, 2190-bp insertion was identified as a spur-specific, solo LTR (sLTR) located at the 1038th nucleotide of another sLTR, which was 1536 bp in length. This insertion-within-an-insertion was localized within a preexisting Gypsy-50 retrotransposon at position 3,762,767 on chromosome 4. The analysis of transcriptional activity of the two sLTRs (the 2190- and 1536-bp inserts) indicated that the 2190-bp sLTR is a promoter, capable of bidirectional transcription. GUS expression in the 2190-bp-sense and 2190-bp-antisense transgenic lines was prominent in stems. In contrast, no promoter activity from either the sense or the antisense strand of the 1536-bp sLTR was detected. From ~150 kb of DNA on each side of the 2190 bp, sLTR insertion site, corresponding to 300 kb of the 'Golden Delicious' genome, 23 genes were predicted. Ten genes had predicted functions that could affect shoot development. This first report, of a sLTR insertion associated with the evolution of apple spur mutation, will facilitate apple breeding, cloning of spur-related genes, and discovery of mechanisms behind dwarf habit.


Assuntos
Malus/genética , Mutagênese Insercional , Mutação , Retroelementos/genética , Sequências Repetidas Terminais/genética , DNA de Plantas/química , DNA de Plantas/genética , Genes de Plantas/genética , Genoma de Planta/genética , Malus/crescimento & desenvolvimento , Caules de Planta/genética , Caules de Planta/crescimento & desenvolvimento , Polimorfismo Genético , Análise de Sequência de DNA
6.
Plant J ; 90(2): 276-292, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28107780

RESUMO

Flavonoids are major polyphenol compounds in plant secondary metabolism. Wild red-fleshed apples (Malus sieversii f. niedzwetzkyana) are an excellent resource because of their much high flavonoid content than cultivated apples. In this work, R6R6, R6R1 and R1R1 genotypes were identified in an F1 segregating population of M. sieversii f. niedzwetzkyana. Significant differences in flavonoid composition and content were detected among the three genotypes by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry analysis. Furthermore, two putative flavonoid-related genes encoding R2R3-MYB transcription factors, designated MYB12 and MYB22, were cloned and characterized. The expression patterns of MYB12 and MYB22 directly correlated with those of leucoanthocyanidin reductase and flavonol synthase, respectively. Their roles in flavonoid biosynthesis were identified by overexpression in apple callus and ectopic expression in Arabidopsis. MYB12 expression in the Arabidopsis TT2 mutant complemented its proanthocyanidin-deficient phenotype. Likewise, MYB22 expression in an Arabidopsis triple mutant complemented its flavonol-deficient phenotype. MYB12 could interact with bHLH3 and bHLH33 and played an essential role in proanthocyanidin synthesis. MYB22 was found to activate flavonol pathways by combining directly with the flavonol synthase promoter. Our findings provide a valuable perspective on flavonoid synthesis and provide a basis for breeding elite functional apples with a high flavonoid content.


Assuntos
Flavonóis/metabolismo , Malus/metabolismo , Proteínas de Plantas/metabolismo , Proantocianidinas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Genótipo , Malus/genética , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Zhongguo Zhong Yao Za Zhi ; 29(2): 141-6, 2004 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15719680

RESUMO

OBJECTIVE: To establish the fingerprint detecting standard of Qingyin injection. METHOD: By adopting GC and HPLC, camphor and chlorogenic acid were used as reference material. To analyze separately Qingyin injection which contains volatile and non-volatile chemials. According to the technical requirements of fingerprint on Injection of Chinese traditional medicine, we calculated their bn relative retention time and area proportionality of peaks to determine the common peaks of fingerprint. RESULT: On the basis of systematic methodalogy, we tested and analyzed 13 batches of sample injection so as to establish GC and HPLC fingerprint of the injection. CONCLUSION: 15 common peaks on GC and 6 common peaks as well as their retention time and area proportionality on HPLC can be used as the important parameters of the quality control for Qingyin injection.


Assuntos
Artemisia annua/química , Medicamentos de Ervas Chinesas/química , Lonicera/química , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão/métodos , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/isolamento & purificação , Injeções , Controle de Qualidade
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