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1.
J Am Chem Soc ; 146(9): 6336-6344, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38381858

RESUMO

Actuating materials convert different forms of energy into mechanical responses. To satisfy various application scenarios, they are desired to have rich categories, novel functionalities, clear structure-property relationships, fast responses, and, in particular, giant and reversible shape changes. Herein, we report a phase transition-driven ferroelectric crystal, (rac-3-HOPD)PbI3 (3-HOPD = 3-hydroxypiperidine cation), showing intriguingly large and anisotropic room-temperature actuating behaviors. The crystal consists of rigid one-dimensional [PbI3] anionic chains running along the a-axis and discrete disk-like cations loosely wrapping around the chains, leaving room for anisotropic shape changes in both the b- and c-axes. The shape change is switched by a ferroelectric phase transition occurring at around room temperature (294 K), driven by the exceptionally synergistic order-disorder and displacive phase transition. The rotation of the cations exerts internal pressure on the stacking structure to trigger an exceptionally large displacement of the inorganic chains, corresponding to a crystal lattice transformation with length changes of +24.6% and -17.5% along the b- and c-axis, respectively. Single crystal-based prototype devices of circuit switches and elevators have been fabricated by exploiting the unconventional negative temperature-dependent actuating behaviors. This work provides a new model for the development of multifunctional mechanically responsive materials.

2.
Metab Eng ; 81: 182-196, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38103887

RESUMO

Anthocyanins are widely distributed pigments in flowering plants with red, purple or blue colours. Their properties in promoting heath make anthocyanins perfect natural colourants for food additives. However, anthocyanins with strong colour and stability at neutral pH, suitable as food colourants are relatively rare in nature. Acylation increases anthocyanin stability and confers bluer colour. In this study, we isolated two anthocyanin regulators SbMyb75 and SbDel from S. baicalensis, and showed that constitutive expression of the two TFs led to accumulation of anthocyanins at high levels in black carrot hairy roots. However, these hairy roots had severe growth problems. We then developed a ß-estradiol inducible system using XVE and a Lex-35S promoter, to initiate expression of the anthocyanin regulators and induced this system in hairy roots of black carrot, tobacco and morning glory. Anthocyanins with various decorations were produced in these hairy roots without any accompanying side-effects on growth. We further produced highly acylated anthocyanins with blue colour in a 5 L liquid culture in a bioreactor of hairy roots from morning glory. We provide here a strategy to produce highly decorated anthocyanins without the need for additional engineering of any of the genes encoding decorating enzymes. This strategy could be transferred to other species, with considerable potential for natural colourant production for the food industries.


Assuntos
Antocianinas , Nicotiana , Antocianinas/genética , Nicotiana/genética , Reatores Biológicos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética
3.
Mitochondrial DNA B Resour ; 8(8): 836-840, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37554696

RESUMO

Duck breed Longshengcui (Anas platyrhynchos Linnaeus, 1758 breed Longshengcui, LSC) is one of the famous native breed of the Guangxi Zhuang Nationality Autonomous Region in China. In this study, we report the complete mitochondrial genome of LSC. The mitogenome (GenBank accession no. MZ895120) has 16,602 bp in length and consisted of the well-known 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and the control region. The phylogenetic analysis showed that LSC and Zhijiang duck have highly similar genetic relationship. These results are helpful for the conservation of genetic resources and phylogeny of this species.

4.
Front Immunol ; 14: 1285052, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38111585

RESUMO

Cannabinoids are a group of bioactive compounds abundantly present in Cannabis sativa plant. The active components of cannabis with therapeutic potential are known as cannabinoids. Cannabinoids are divided into three groups: plant-derived cannabinoids (phytocannabinoids), endogenous cannabinoids (endocannabinoids), and synthetic cannabinoids. These compounds play a crucial role in the regulation various physiological processes including the immune modulation by interacting with the endocannabinoid system (A complex cell-signaling system). Cannabinoid receptor type 1 (CB1) stimulates the binding of orexigenic peptides and inhibits the attachment of anorexigenic proteins to hypothalamic neurons in mammals, increasing food intake. Digestibility is unaffected by the presence of any cannabinoids in hemp stubble. Endogenous cannabinoids are also important for the peripheral control of lipid processing in adipose tissue, in addition to their role in the hypothalamus regulation of food intake. Regardless of the kind of synaptic connection or the length of the transmission, endocannabinoids play a crucial role in inhibiting synaptic transmission through a number of mechanisms. Cannabidiol (CBD) mainly influences redox equilibrium through intrinsic mechanisms. Useful effects of cannabinoids in animals have been mentioned e.g., for disorders of the cardiovascular system, pain treatment, disorders of the respiratory system or metabolic disorders. Dietary supplementation of cannabinoids has shown positive effects on health, growth and production performance of small and large animals. Animal fed diet supplemented with hemp seeds (180 g/day) or hemp seed cake (143 g/kg DM) had achieved batter performance without any detrimental effects. But the higher level of hemp or cannabinoid supplementation suppress immune functions and reduce productive performance. With an emphasis on the poultry and ruminants, this review aims to highlight the properties of cannabinoids and their derivatives as well as their significance as a potential feed additive in their diets to improve the immune status and health performance of animals.


Assuntos
Canabinoides , Cannabis , Animais , Canabinoides/farmacologia , Canabinoides/uso terapêutico , Cannabis/química , Endocanabinoides , Dieta , Imunidade , Mamíferos
5.
DNA Cell Biol ; 34(12): 717-27, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26465082

RESUMO

To construct and screen short hairpin RNA (shRNA) targeting vascular endothelial growth factor (VEGF), and investigate potential values of VEGF-shRNA on angiogenesis and growth in renal cell carcinoma (RCC) in a xenograft tumor model. VEGF-shRNA fragment was designed to connect plasmid vector, and RCC cells were transfected with shRNA. Real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR) was used to detect interference efficiency of VEGF gene. The xenograft tumor model was established in nude mice, and mice were randomly divided into blank control (BC) group, negative control (NC) group, and experimental group. RNA interference (RNAi) effect was detected by immunohistochemistry, and tumor volume changes were observed. Tumor-bearing nude mice model was established and mice were randomly divided into BC group, NC group, and treatment group. The tumor volume changes and tumor inhibition rate were recorded, and angiogenesis status was observed. The apoptosis of tumor cells and genetic toxicity of VEGF-shRNA were detected. VEGF-shRNA can inhibit VEGF mRNA expression with an inhibition ratio of 72.3%. Compared with NC group and BC group, experimental group presents smaller tumor volume, weight, and poor growth (all p < 0.05). Positive VEGF rate in experimental group is significantly lower than that in NC group and BC group (all p < 0.05). Significantly lower tumor volume, less microvessel density (MVD) value, and higher apoptotic index (AI) are found in treatment group compared with BC group and NC group (all p < 0.05). There was no significant difference in AI between treatment group and BC group regarding adjacent normal tissues (p > 0.05). VEGF plays an important role in the occurrence and development of RCC, chemical synthesis of VEGF small interfering RNA (siRNA) can specifically inhibit VEGF expression, angiogenesis and growth in RCC, and can promote cell apoptosis without genetic toxicity to normal tissues.


Assuntos
Carcinoma de Células Renais/patologia , Inativação Gênica , Vetores Genéticos , Neoplasias Renais/patologia , Lentivirus/genética , Interferência de RNA , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Carcinoma de Células Renais/irrigação sanguínea , Células HEK293 , Xenoenxertos , Humanos , Neoplasias Renais/irrigação sanguínea , Luciferases/genética , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase em Tempo Real
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