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1.
Front Bioeng Biotechnol ; 12: 1386534, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38655386

RESUMEN

Extensive research on zeolitic imidazolate framework (ZIF-8) and its derivatives has highlighted their unique properties in nanomedicine. ZIF-8 exhibits advantages such as pH-responsive dissolution, easy surface functionalization, and efficient drug loading, making it an ideal nanosystem for intelligent drug delivery and phototherapy. These characteristics have sparked significant interest in its potential applications in tissue regeneration, particularly in bone, skin, and nerve regeneration. This review provides a comprehensive assessment of ZIF-8's feasibility in tissue engineering, encompassing material synthesis, performance testing, and the development of multifunctional nanosystems. Furthermore, the latest advancements in the field, as well as potential limitations and future prospects, are discussed. Overall, this review emphasizes the latest developments in ZIF-8 in tissue engineering and highlights the potential of its multifunctional nanoplatforms for effective complex tissue repair.

2.
Chin Med J (Engl) ; 137(5): 533-546, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38321811

RESUMEN

ABSTRACT: Lung cancer remains the most common cause of cancer death. Given the continued research into new drugs and combination therapies, outcomes in lung cancer have been improved, and clinical benefits have been expanded to a broader patient population. However, the overall cure and survival rates for lung cancer patients remain low, especially in metastatic cases. Among the available lung cancer treatment options, such as surgery, radiation therapy, chemotherapy, targeted therapies, and alternative therapies, immunotherapy has shown to be the most promising. The exponential progress in immuno-oncology research and recent advancements made in the field of immunotherapy will further increase the survival and quality of life for lung cancer patients. Substantial progress has been made in targeted therapies using tyrosine kinase inhibitors and monoclonal antibody immune checkpoint inhibitors with many US Food And Drug Administration (FDA)-approved drugs targeting the programmed cell death ligand-1 protein (e.g., durvalumab, atezolizumab), the programmed cell death-1 receptor (e.g., nivolumab, pembrolizumab), and cytotoxic T-lymphocyte-associated antigen 4 (e.g., tremelimumab, ipilimumab). Cytokines, cancer vaccines, adoptive T cell therapies, and Natural killer cell mono- and combinational therapies are rapidly being studied, yet to date, there are currently none that are FDA-approved for the treatment of lung cancer. In this review, we discuss the current lung cancer therapies with an emphasis on immunotherapy, including the challenges for future research and clinical applications.


Asunto(s)
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/terapia , Calidad de Vida , Nivolumab , Inmunoterapia , Terapia Combinada , Antígeno B7-H1/metabolismo
3.
Plants (Basel) ; 12(18)2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37765398

RESUMEN

Light is a crucial environmental signal and a form of photosynthetic energy for plant growth, development, and nutrient formation. To explore the effects of light quality on the growth and nutritional qualities of greenhouse-grown lettuce (Lactuca sativa L.), lettuce was cultivated under supplementary white (W) light-emitting diodes (LEDs); white plus ultraviolet A LEDs (W+UV); white plus far-red LEDs (W+FR); and the combination of white, far-red, and UV-A LEDs (W+FR+UV) for 25 days, with lettuce grown under natural sunlight used as the control. The results indicate that the leaf length and leaf width values for lettuce grown under the W+FR+UV treatment were significantly higher than those of lettuce grown under other supplementary light treatments. The highest values of shoot fresh weight, shoot dry weight, root fresh weight, and root dry weight were recorded under the W+FR treatment (4.0, 6.0, 8.0, and 12.4 times higher than those under the control treatment, respectively). Lettuce grown under the W+FR treatment exhibited the highest total chlorophyll content (39.1%, 24.6%, and 16.2% higher than that under the W, W+UV, and W+FR+UV treatments, respectively). The carotenoid content of lettuce grown under the W+FR treatment was the highest among all treatments. However, the root activity of greenhouse-grown lettuce was the highest under the W+FR+UV treatment. Soluble sugar content, cellulose content, and starch content in the lettuce responded differently to the light treatments and were highest under the W+UV treatment. In summary, supplementary light promoted growth and nutrient accumulation in lettuce. Specifically, white plus far-red light promoted lettuce growth, and white plus UV increased some specific compounds in greenhouse-grown lettuce. Our findings provide valuable references for the application of light-supplementation strategies to greenhouse lettuce production.

4.
Int J Biol Macromol ; 245: 125581, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37385315

RESUMEN

Three fractions of FHP20, FHP40 and FHP60 were obtained from freeze-dried hawthorn pectin by gradient ethanol precipitation (20-60 %), and their physicochemical properties and adsorption performance on Pb2+ were investigated. It was found that the content of galacturonic acid (GalA) and esterification of FHP fractions gradually reduced with the increase of ethanol concentration. FHP60 had the lowest molecular weight (60.69 × 103 Da), and the composition and proportion of monosaccharides were significantly different. The experimental results of Pb2+ adsorption showed that the adsorption process fitted well with the Langmuir monolayer adsorption and the pseudo-second-order models. Our findings suggested that pectin fractions with good homogeneity of molecular weight and chemical construction can be obtained by gradient ethanol precipitation, and hawthorn pectin could be developed as a potential adsorbent for Pb2+ removal.


Asunto(s)
Crataegus , Contaminantes Químicos del Agua , Pectinas/química , Adsorción , Plomo , Etanol , Contaminantes Químicos del Agua/análisis , Cinética , Concentración de Iones de Hidrógeno
5.
Ying Yong Sheng Tai Xue Bao ; 34(2): 305-314, 2023 Feb.
Artículo en Chino | MEDLINE | ID: mdl-36803707

RESUMEN

To solve the problems of understory plant shortage and biodiversity reduction caused by high tree density of Robinia pseudoacacia plantations on the Loess Plateau in northwest China, we analyzed the data collected by field survey and from literatures. We used the upper boundary line method to examine the impacts of canopy density on understory plant diversity. Based on field survey at the Guanshan Forest Farm of Jingchuan County of Gansu Pro-vince, the species number of understory plants in R. pseudoacacia plantations was higher than that in natural grassland (91 vs. 78). The dominant species varied with canopy density, which was completely different from that of natural grassland. A comprehensive analysis of both literature data and field survey data showed that, when mean annual precipitation (MAP) <550 mm or >550 mm, the increases in canopy density first led to a stable understory plant coverage and then a sharp or slight decrease, and understory plant biomass showed a sharp and continuous decrease or a slight increase and then decrease. Understory plant species richness and other diversity indices (Shannon, Simpson, and Pielou indices) first increase and then decrease, with bigger variation range under lower MAP. In all, the characteristics (coverage, biomass and species diversity, etc.) of understory plant community in R. pseudoacacia plantations were strongly affected by canopy density, with higher sensitivity under lower MAP. There was a general threshold range of canopy density of 0.45-0.6. When canopy density was above or below this thre-shold range, it would lead to a rapid decrease of the most characteristics of understory plant community. Therefore, keeping canopy density within the rational range of 0.45-0.6 in the management of R. pseudoacacia plantations is the key to make all the above-mentioned understory plant characteristics at relatively high level.


Asunto(s)
Robinia , Suelo , Bosques , Biodiversidad , China , Ecosistema
6.
J Nanobiotechnology ; 21(1): 57, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36803772

RESUMEN

BACKGROUND: Globally, millions of patients suffer from regenerative deficiencies, such as refractory wound healing, which is characterized by excessive inflammation and abnormal angiogenesis. Growth factors and stem cells are currently employed to accelerate tissue repair and regeneration; however, they are complex and costly. Thus, the exploration of new regeneration accelerators is of considerable medical interest. This study developed a plain nanoparticle that accelerates tissue regeneration with the involvement of angiogenesis and inflammatory regulation. METHODS: Grey selenium and sublimed sulphur were thermalized in PEG-200 and isothermally recrystallised to composite nanoparticles (Nano-Se@S). The tissue regeneration accelerating activities of Nano-Se@S were evaluated in mice, zebrafish, chick embryos, and human cells. Transcriptomic analysis was performed to investigate the potential mechanisms involved during tissue regeneration. RESULTS: Through the cooperation of sulphur, which is inert to tissue regeneration, Nano-Se@S demonstrated improved tissue regeneration acceleration activity compared to Nano-Se. Transcriptome analysis revealed that Nano-Se@S improved biosynthesis and ROS scavenging but suppressed inflammation. The ROS scavenging and angiogenesis-promoting activities of Nano-Se@S were further confirmed in transgenic zebrafish and chick embryos. Interestingly, we found that Nano-Se@S recruits leukocytes to the wound surface at the early stage of regeneration, which contributes to sterilization during regeneration. CONCLUSION: Our study highlights Nano-Se@S as a tissue regeneration accelerator, and Nano-Se@S may provide new inspiration for therapeutics for regenerative-deficient diseases.


Asunto(s)
Nanocompuestos , Nanopartículas , Selenio , Embrión de Pollo , Humanos , Ratones , Animales , Selenio/farmacología , Selenio/química , Pez Cebra/metabolismo , Especies Reactivas de Oxígeno , Cicatrización de Heridas , Nanopartículas/química , Inflamación , Azufre
7.
Medicine (Baltimore) ; 101(48): e32089, 2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36482533

RESUMEN

As a new drug for local dental anesthesia, articaine has become popular in the clinic in recent years. In this review, we describe the development of articaine, explain its mechanism of action, compare its efficacy with that of other commonly used local anesthetics in dental treatment, and summarize the application of articaine in special populations. In conclusion, the anesthetic efficacy of articaine in clinical dental treatment is better than that of lidocaine, and its safety is not statistically different from that of lidocaine. In particular, articaine has several advantages and can be selected flexibly for clinical use. Atecaine has great potential for wide application in dental clinics in the near future.


Asunto(s)
Anestesia Local , Carticaína , Humanos , Carticaína/farmacología , Clínicas Odontológicas
8.
Carbohydr Polym ; 298: 120121, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36241293

RESUMEN

Five types of hawthorns were obtained using hot air drying (HH), vacuum freeze-drying (FH), Parched processing (PH), Charred processing (CH), and blackening (BH). Five types of pectins (HHP, FHP, PHP, CHP, BHP) were extracted and characterized based on a series of characterization methods. The results indicated that the esterification and molecular weight of BHP were the lowest, which were 30.92 % and 73.67 × 103 (g/mol), respectively. FHP had the highest apparent viscosity and molecular weight (464.42 × 103 g/mol). PHP and CHP differ in galacturonic acid, molecular weight, and monosaccharide composition depending on the time of processing. The emulsion of HHP had the best stability, and the emulsification properties of FHP, PHP, and CHP also showed better performance compared to BHP. In conclusion, our results showed that different processing methods of hawthorn affected the physicochemical properties of pectin, and pectin with specific properties could be obtained by choosing the appropriate processing method.


Asunto(s)
Crataegus , Pectinas , Emulsiones , Peso Molecular , Monosacáridos , Pectinas/química , Viscosidad
9.
Front Pharmacol ; 13: 940463, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36003517

RESUMEN

Background: Chronic stress-induced diarrhea is a common clinical condition, characterized by an abnormal bowel movement and loose stools, which lacks effective treatment in the clinic. Si-Ni-San (SNS) is a compound traditional Chinese medicine extensively used in China for stress-related diarrhea. However, the mechanism is unclear. Methods: Male Wistar rats (200 ± 20 g) were placed in a restraint cylinder and fixed horizontally for 3 h once daily for 21 consecutive days to establish a chronic restraint stress (CRS) rat model. SNS (0.6944 g/kg or 1.3888 g/kg) was given by gavage 1 h before the restraint once daily for 21 consecutive days. We examined the fecal score, dopamine ß hydroxylase (DßH), and c-fos expression in locus coeruleus, norepinephrine (NE) content in ileum and plasma, expression of α1 adrenergic receptors, MLCK, MLC, and p-MLC in the colon and mesenteric arteries, contraction of isolated mesenteric arteries, The expression of subunit δ of ATP synthase (ATP5D) in intestinal tissues, ATP, ADP, and AMP content in the ileum and colon, occludin expression between ileum epithelial cells, the number of enterochromaffin cells (ECs) and mast cells (MCs) in the ileum, and 5-hydroxytryptamine (5-HT) content in the ileum and plasma. Results: After SNS treatment, the fecal score was improved. The increased expression of DßH and c-fos in locus coeruleus was inhibited. SNS suppressed the increased NE content in the ileum and plasma, down-regulated α1 adrenergic receptors in mesenteric arteries and MLCK, MLC, p-MLC in the colon and mesenteric arteries, and inhibited the contraction of mesenteric arteries. SNS also increased the ATP content in the ileum and colon, inhibited low expression of ATP5D in intestinal tissues, inhibited the decrease of ATP/ADP in the ileum and ATP/AMP in the colon, and up-regulated the occludin expression between ileum epithelial cells. In addition, SNS inhibited the increase of ECs and MCs in the ileum and the increase of 5-HT content in the ileum and plasma. Conclusion: This study demonstrated that SNS could improve CRS-induced abnormal feces in rats. This effect was related to the inhibition of CRS-induced increased expression of DßH and c-fos in the locus coeruleus, NE content in the ileum and plasma, and the contraction of isolated mesenteric arteries; inhibition of energy metabolism abnormality and decreased occludin expression; inhibition of increased ECs and MCs in the ileum, and 5-HT content in the ileum and plasma.

10.
Artículo en Inglés | MEDLINE | ID: mdl-35966754

RESUMEN

Background: Back muscle injury is the most common illness involved in aged people. Muscular satellite cells, playing a key role in the muscle repairing process, are gradually losing their regenerative ability with aging, which attenuates the injured muscle repairing process. Electroacupuncture at Weizhong acupoint has been widely used in the treatment of young and aged patients with back muscle damage. Its efficacy has been proven by a randomized double-blind placebo clinical trial. However, the rehabilitation mechanisms are largely unknown. This study will explore the possible mechanisms associated with electroacupuncture at the Weizhong acupoint (BL 40) promoting muscle repairing ability. Method: A total of 58 male and female Sprague-Dawley rats were divided into a younger group (4-month-old) and an aged group (16-month-old), younger and aged rats were further divided as a sham, injured, injured rats treated with electroacupuncture at Weizhong point or treated with Non-Weizhong point groups. The back muscle injury model was produced in rats as a previously described method with modification. Furthermore, Weizhong acupoints underwent electroacupuncture treatment with 15 V magnitude, 2 Hz/10 Hz frequency density, 1.0 mA current intensity, and 10 min each day for 10 consecutive days using HANS's electroacupuncture apparatus. After the last treatment, the paravertebral muscles and serum of all animals were undergone histological, immunohistochemistry, and flow cytometry analysis. Serum levels of Creatine Kinase (CK) and proinflammatory cytokine, interleukin 6 (IL-6), were measured separately by using ELISA kit. Results: Electroacupuncture of Weizhong (BL 40) acupoints significantly attenuated back muscle damage in both young and aged rats, increasing PAX7 (a marker of muscle satellite cells) and MYOD (major marker of myoblasts) cells, simultaneously, reducing serum proinflammatory cytokines, IL-6, and downregulation of p38 MAPK signaling in aged muscular satellite cells. Conclusion: Our studies suggest that electroacupuncture of Weizhong (BL 40) acupoints can restore aged back muscular satellite cells and their regeneration capacity. These suggested electroacupuncture may be a potential means of promoting rehabilitation for muscular injury in aged patients.

11.
Anal Methods ; 12(36): 4473-4478, 2020 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-32869773

RESUMEN

The amount of copper affects the quality of herbal medicine greatly, it is necessary to develop some simple and sensitive methods to detect copper for the remote or resource-limited area. An electronic balance is one of the most familiar equipment that can be found nearly in all laboratories. The presence of Cu(i) can catalyze azide-alkyne cycloaddition reaction (called as click chemistry) with high efficiency. In this study, a simple method had been developed to detect copper ions in herbal medicine using an electronic balance as a readout device based on click chemistry. Cu(ii) is reduced to Cu(i) by sodium ascorbate in situ, which induces the "click" reaction between azido-DNA modified magnetic beads (MB-DNA) and alkynyl-DNA modified platinum nanoparticles (Pt NP-DNA) and results in the fixing of the platinum nanoparticles on the beads (called as MB-Pt NPs). MB-Pt NPs can be separated by a magnetic frame easily and transferred into a drainage reaction device containing hydrogen peroxide. Then, hydrogen peroxide can be decomposed by Pt NPs modified on MB to generate oxygen, which increases the pressure in the drainage reaction device and forces the water in the system to be discharged. The weight of the discharged water can be easily and accurately measured by an electronic balance. The weight of the water has a linear relationship with Cu(ii) in the range of 2.0-200 µM and a detection limit of 0.83 µM under 30 min of collected time. This method does not need complicated and expensive instruments, skilled technicians, and a complex data processing process. The proposed method had been applied to detect copper ions in herbal medicine with satisfactory results.


Asunto(s)
Química Clic , Nanopartículas del Metal , Cobre , Electrónica , Medicina de Hierbas , Iones , Platino (Metal)
12.
Int J Biol Macromol ; 112: 537-547, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29382583

RESUMEN

Xanthine oxidase (XOD) is a key enzyme that catalyzes xanthine to uric acid. Most of the urate-lowering medicines targeting XOD have a limited effect on alleviating inflammation in spite of significant effects on decreasing serum uric acid level. In this study, we produced and characterized a novel monoclonal antibody (Anti-XOD mAb) using hybridoma technology based on a novel peptide OI5P-1(O-IA2(5)-P2-1),which containing a B-cell epitope of XOD and a novel Th2 built-in adjuvant I5P-1(IA2(5)-P2-1). Results of western blotting and cross-reactivity assay indicated that the mAb binds specifically to XOD and the affinity was 2.523×1010L/mol. The mAb reduced serum uric acid level and hepatic xanthine oxidase activity in potassium oxonate induced mice. A decreased methane dicarboxylic aldehyde level and an improved superoxide dismutase level in mAb treated mice indicated anti-lipid peroxidation effects of the mAb. Moreover, the mAb showed a significant immunomodulatory effect which could shift Th1/Th2 balance to Th2-dominant immunity. The mAb treatment alleviates inflammation induced by potassium oxonate, superior to the small molecule allopurinol treatment. For the first time, these results showed that the anti-XOD mAb may serve as a promising therapeutic approach for inflammatory response related to uric acid.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Inmunoglobulina G/uso terapéutico , Inflamación/tratamiento farmacológico , Xantina Oxidasa/antagonistas & inhibidores , Alopurinol/farmacología , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/aislamiento & purificación , Anticuerpos Monoclonales/farmacología , Afinidad de Anticuerpos/efectos de los fármacos , Antioxidantes/metabolismo , Creatinina/sangre , Reacciones Cruzadas/inmunología , Femenino , Sueros Inmunes , Inmunización , Inmunoglobulina G/farmacología , Inflamación/sangre , Inflamación/patología , Riñón/efectos de los fármacos , Hígado/enzimología , Malondialdehído/sangre , Ratones , Ratones Endogámicos BALB C , Ácido Oxónico , Sustancias Protectoras/farmacología , Bazo/patología , Superóxido Dismutasa/sangre , Células TH1/efectos de los fármacos , Células TH1/inmunología , Células Th2/efectos de los fármacos , Células Th2/inmunología , Urea/sangre , Ácido Úrico/sangre , Xantina Oxidasa/metabolismo
13.
Sci Rep ; 7(1): 7937, 2017 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-28801632

RESUMEN

Rising CO2 concentration, a driving force of climate change, is impacting global food security by affecting plant physiology. Nevertheless, the effects of elevated CO2 on primary and secondary metabolism in tea plants (Camellia sinensis L.) still remain largely unknown. Here we showed that exposure of tea plants to elevated CO2 (800 µmol mol-1 for 24 d) remarkably improved both photosynthesis and respiration in tea leaves. Furthermore, elevated CO2 increased the concentrations of soluble sugar, starch and total carbon, but decreased the total nitrogen concentration, resulting in an increased carbon to nitrogen ratio in tea leaves. Among the tea quality parameters, tea polyphenol, free amino acid and theanine concentrations increased, while the caffeine concentration decreased after CO2 enrichment. The concentrations of individual catechins were altered differentially resulting in an increased total catechins concentration under elevated CO2 condition. Real-time qPCR analysis revealed that the expression levels of catechins and theanine biosynthetic genes were up-regulated, while that of caffeine synthetic genes were down-regulated in tea leaves when grown under elevated CO2 condition. These results unveiled profound effects of CO2 enrichment on photosynthesis and respiration in tea plants, which eventually modulated the biosynthesis of key secondary metabolites towards production of a quality green tea.


Asunto(s)
Vías Biosintéticas/efectos de los fármacos , Camellia sinensis/metabolismo , Dióxido de Carbono/farmacología , Fotosíntesis/efectos de los fármacos , Metabolismo Secundario/efectos de los fármacos , Té/química , Cafeína/análisis , Camellia sinensis/efectos de los fármacos , Camellia sinensis/genética , Carbono/análisis , Catequina/análisis , Respiración de la Célula/efectos de los fármacos , Calidad de los Alimentos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Nitrógeno/análisis , Proteínas de Plantas/genética , Almidón/análisis , Té/efectos de los fármacos
14.
J Plant Physiol ; 214: 145-151, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28482335

RESUMEN

Flavonoids are one of the key secondary metabolites determining the quality of tea. Although exogenous brassinosteroid (BR), a steroidal plant hormone, can stimulate polyphenol biosynthesis in tea plants (Camellia sinensis L.), the relevance of endogenous BR in flavonoid accumulation and the underlying mechanisms remain largely unknown. Here we show that BR enhances flavonoid concentration in tea leaves by inducing an increase in the endogenous concentration of nitric oxide (NO). Notably, exogenous BR increased levels of flavonoids as well as NO in a concentration dependent manner, while suppression of BR levels by an inhibitor of BR biosynthesis, brassinazole (BRz), decreased the concentrations of both flavonoids and NO in tea leaves. Interestingly, combined treatment of BR and BRz reversed the inhibitory effect of BRz alone on the concentrations of flavonoids and NO. Likewise, exogenous NO also increased flavonoids and NO levels dose-dependently. When the NO level in tea leaves was suppressed by using a NO scavenger, 2,4-carboxyphenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO), flavonoid concentration dramatically decreased. Although individual application of 0.1µM BR increased the concentrations of flavonoids and NO, combined treatment with exogenous NO scavenger, cPTIO, reversed the effect of BR on flavonoid concentration. Furthermore, BR or sodium nitroprusside (SNP) promoted but cPTIO inhibited the transcription and activity of phenylalanine ammonia-lyase (PAL) in leaves, while combined treatment of BR with SNP or cPTIO had no additive effect. The results of this study suggest that an optimal level of endogenous NO is essential for BR-induced promotion of flavonoid biosynthesis in tea leaves. In conclusion, this study unveiled a crucial mechanism of BR-induced flavonoid biosynthesis, which might have potential implication in improving the quality of tea.


Asunto(s)
Brasinoesteroides/farmacología , Camellia sinensis/metabolismo , Flavonoides/metabolismo , Óxido Nítrico/metabolismo , Benzoatos/farmacología , Camellia sinensis/efectos de los fármacos , Imidazoles/farmacología , Fenilanina Amoníaco-Liasa/metabolismo
15.
Plant Physiol Biochem ; 106: 327-35, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27380366

RESUMEN

Leaf position represents a specific developmental stage that influences both photosynthesis and respiration. However, the precise relationships between photosynthesis and respiration in different leaf position that affect tea quality are largely unknown. Here, we show that the effective quantum yield of photosystem II [ΦPSⅡ] as well as total chlorophyll concentration (TChl) of tea leaves increased gradually with leaf maturity. Moreover, respiration rate (RR) together with total nitrogen concentration (TN) decreased persistently, but total carbon remained unchanged during leaf maturation. Analyses of major N-based organic compounds revealed that decrease in TN was attributed to a significant decrease in the concentration of caffeine and amino acids (AA) in mature leaves. Furthermore, soluble sugar (SS) decreased, but starch concentration increased with leaf maturity, indicating that source-sink relationship was altered during tea leaf development. Detailed correlation analysis showed that ΦPSⅡ was negatively correlated with RR, SS, starch, tea polyphenol (TP), total catechins and TN, but positively correlated with TChl; while RR was positively correlated with TN, SS, TP and caffeine, but negatively correlated with TChl and starch concentrations. Our results suggest that biosynthesis of chlorophyll, catechins and polyphenols is closely associated with photosynthesis and respiration in different leaf position that greatly influences the relationship between primary and secondary metabolism in tea plants.


Asunto(s)
Camellia sinensis/crecimiento & desarrollo , Camellia sinensis/metabolismo , Carbono/metabolismo , Nitrógeno/metabolismo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/metabolismo , Aminoácidos/análisis , Vías Biosintéticas , Cafeína/análisis , Carbohidratos/análisis , Catequina/análisis , Respiración de la Célula , Clorofila/metabolismo , Fotosíntesis , Complejo de Proteína del Fotosistema II/metabolismo , Polifenoles/metabolismo , Solubilidad , Almidón/metabolismo
16.
Phytopathology ; 106(11): 1270-1277, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27392179

RESUMEN

Caffeine, the major purine alkaloid in tea has long been known for its role in plant defense. However, its effect on Colletotrichum gloeosporioides that causes brown blight disease in tea is largely unknown especially under elevated CO2. Here we show that elevated CO2 reduced endogenous caffeine content in tea leaves, but sharply increased susceptibility of tea to C. gloeosporioides. The expression of C. gloeosporioides actin gene was gradually increased during the postinoculation period. In contrast, foliar application of caffeine decreased the C. gloeosporioides-induced necrotic lesions and the expression of C. gloeosporioides actin. Analysis of endogenous jasmonic acid (JA) content revealed that exogenous caffeine could induce JA content under both CO2 conditions in absence of fungal infection; however, in presence of fungal infection, caffeine increased JA content only under elevated CO2. Furthermore, exogenous caffeine enhanced lipoxygenase (LOX) activity and its biosynthetic gene expression under both CO2 conditions, indicating that increased JA biosynthesis via LOX pathway by caffeine might strengthen plant defense only under elevated CO2, while caffeine-induced defense under ambient CO2 might be associated with JA-independent LOX pathway in tea. These results provide novel insights into caffeine-induced plant defense mechanisms that might help to develop an eco-friendly approach for disease control.


Asunto(s)
Cafeína/farmacología , Camellia sinensis/efectos de los fármacos , Colletotrichum/patogenicidad , Ciclopentanos/metabolismo , Lipooxigenasas/efectos de los fármacos , Oxilipinas/metabolismo , Enfermedades de las Plantas/inmunología , Reguladores del Crecimiento de las Plantas/metabolismo , Cafeína/metabolismo , Camellia sinensis/inmunología , Camellia sinensis/microbiología , Dióxido de Carbono/farmacología , Resistencia a la Enfermedad , Regulación de la Expresión Génica de las Plantas , Lipooxigenasas/genética , Lipooxigenasas/metabolismo , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantones/efectos de los fármacos , Plantones/inmunología , Plantones/microbiología
17.
Chin J Integr Med ; 22(10): 778-82, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27412588

RESUMEN

OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation on the expressions of angiotensinogen (AGT), angiotensin II type 1 receptor (AT1R), endothelin-1 (ET1), and endothelin A receptor (ETAR) mRNA in spontaneously hypertensive rat (SHR) aorta. METHODS: Eighteen male SHRs were randomly divided into three groups, an SHR group, an SHR Baihui (DU 20) and Zusanli (ST 36) acupoint (SHR-AP) group, and an SHR non-acupoint (SHR-NAP) group, with 6 rats in each group. Six Wistar rats were used as a control. Rats in the SHR-AP group were stimulated by DU 20 and ST 36 acupoints, both of which were connected with EA. EA was handled one time every Monday, Wednesday and Friday, for total 24 times (8 weeks). SHRNAP rats were acupointed at a 15°angle flat into 0.5 cm to two points, which were 1 and 2 cm from rail tip separately. EA parameters were the same as the SHR-AP rats. SHR control rats and Wistar rats were fixed without EA. Real-time quantitative polymerase chain reaction (PCR) was used to measure AGT, AT1R, ET1, and ETAR mRNA expression in rat aorta. RESULTS: EA stimulation significantly reduced rat aorta vascular AGT, ET1, ETAR and AT1R mRNA expressions in the SHR-AP and SHR-NAP groups (P <0.01). Among these four genes, AT1R mRNA expression was significantly lower in the SHR-AP than in the SHR-NAP group (P <0.01). CONCLUSION: EA could reduce the AT1R mRNA expression in SHR-AP rat aorta, indicating a potential mechanism for the hypotensive effects of EA.


Asunto(s)
Angiotensinógeno/genética , Aorta/metabolismo , Electroacupuntura , Endotelina-1/genética , Receptor de Angiotensina Tipo 1/genética , Receptor de Endotelina A/genética , Angiotensinógeno/metabolismo , Animales , Aorta/fisiopatología , Presión Sanguínea , Endotelina-1/metabolismo , Regulación de la Expresión Génica , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Endogámicas SHR , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Endotelina A/metabolismo
18.
Ying Yong Sheng Tai Xue Bao ; 26(9): 2632-8, 2015 Sep.
Artículo en Chino | MEDLINE | ID: mdl-26785543

RESUMEN

In this study, we determined the vertical distribution of N2O emission rates in tea soils and its adjacent woodland soils. The results showed that total nitrogen contents, N2O fluxes and cumulative emissions in the tea garden and woodland decreased with the increasing depth of the soil layer, and their average values were greater in tea garden than in woodland. Generally, pH, soil water soluble organic nitrogen (WSON), soil microbial biomass nitrogen (MBN), NO(3-)-N and NH(4+)-N contents had a downward trend with the increasing depth of soil layer. The WSON, MBN, NO(3-)-N and NH(4+)-N contents from each soil layer were greater in tea garden than in woodland, but the pH value in tea garden was lower than that in woodland. The N2O emission rate was significantly positively related with TN, MBN and NH(4+)-N contents, but not with pH value. The N2O emission rate was significantly correlated with WSON content in woodland, but not in tea garden. The N20 emission rate was significantly correlated with NO(3-)-N concentration in tea garden, but not in woodland. WSON/TN and N2O-N/SMBN were averagely greater than in tea garden in woodland, and SMBN/TN was opposite. These results indicated that tea soil was not conducive to accumulate nitrogen pool, maintain soil quality and its sustainable use compared to woodland.


Asunto(s)
Camellia sinensis/fisiología , Bosques , Óxido Nitroso/análisis , Suelo/química , Agricultura , Biomasa , Nitrógeno/análisis , Agua
19.
PLoS One ; 8(11): e75493, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24223114

RESUMEN

Zinc Finger Nucleases (ZFNs), famous for their ability to precisely and efficiently modify specific genomic loci, have been employed in numerous transgenic model organism and cell constructions. Here we employ the ZFNs technology, with homologous recombination (HR), to construct sequence-specific Amyloid Precursor Protein (APP) knock-in cells. With the use of ZFNs, we established APP knock in cell lines with gene-modification efficiencies of about 7%. We electroporated DNA fragment containing the promoter and the protein coding regions of the zinc finger nucleases into cells, instead of the plasmids, to avoid problems associated with off target homologous recombination, and adopted a pair of mutated FokI cleavage domains to reduce the toxic effects of the ZFNs on cell growth. Since over-expression of APP, or a subdomain of it, might lead to an immediately lethal effect, we used the Cre-LoxP System to regulate APP expression. Our genetically transformed cell lines, w5c1 and s12c8, showed detectable APP and Amyloid ß (Aß) production. The Swedish double mutation in the APP coding sequence enhanced APP and Aß abundance. What is more, the activity of the three key secretases in Aß formation could be modulated, indicating that these transgenic cells have potential for drug screening to modify amyloid metabolism in cells. Our transformed cells could readily be propagated in culture and should provide an excellent experimental medium for elucidating aspects of the molecular pathogenesis of Alzheimer's disease, especially those concerning the amyloidogenic pathways involving mutations in the APP coding sequence. The cellular models may also serve as a tool for deriving potentially useful therapeutic agents.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/genética , Desoxirribonucleasas/genética , Fragmentos de Péptidos/genética , Péptidos beta-Amiloides/biosíntesis , Animales , Antiinflamatorios no Esteroideos/farmacología , Apoptosis , Células 3T3 BALB , Secuencia de Bases , Inhibidores de la Colinesterasa/farmacología , División del ADN , Desoxirribonucleasas/biosíntesis , Donepezilo , Evaluación Preclínica de Medicamentos , Galantamina/farmacología , Expresión Génica , Ingeniería Genética , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/genética , Recombinación Homóloga , Humanos , Ibuprofeno/farmacología , Indanos/farmacología , Ratones , Datos de Secuencia Molecular , Fragmentos de Péptidos/biosíntesis , Piperidinas/farmacología , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Dedos de Zinc
20.
Chin J Integr Med ; 19(8): 636-40, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23893135

RESUMEN

Chinese medicines (CMs) are increasingly being used for the treatment of tumors because of their unique advantages. The induction of tumor cell apoptosis is an important method of tumor treatment. Caspase-3 is a member of the caspase (cysteine aspartic proteinases) family of enzymes, which are the major inducers of apoptosis. Caspase-3 activity is often measured in the context of research into anti-tumor drugs that target apoptosis. Many studies have shown that CMs upregulate the expression of caspase-3 in tumor cells via extrinsic and/or intrinsic pathways, removing endogenous suppression of apoptosis and promoting tumor cell death. Therefore, several CMs fulfill the criteria for anti-tumor drugs. In this paper, we review the efficacy of 14 Chinese herbal medicines, across a wide range applications, and discuss their effects on caspase-3 activity in tumor cells.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Caspasa 3/metabolismo , Medicamentos Herbarios Chinos/farmacología , Neoplasias/metabolismo , Antineoplásicos Fitogénicos/uso terapéutico , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Neoplasias/tratamiento farmacológico , Plantas Medicinales/fisiología , Transducción de Señal/efectos de los fármacos
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