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Aim To evaluate the hypolipidemic effect of the total phenylpropanoid glycosides extracted from Ligustrum robustum (Roxb.) Blume (LRTPG) on hyperlipidemic golden hamsters and explore its regulatory effect on intestinal flora. Methods Sixty hamsters were randomly divided into a control group, a model group, a positive drug group, LRTPG-L group, LRTPG-M group, and LRTPG-H group. After the successful induction of the model by high-fat diet, the animals were continuously administered for four weeks, and their blood lipids and liver lipids were detected. The formed feces from the colorectal region of the hamsters in the control group, model group and LRTPG-H group were collected for 16S rDNA sequencing. Results LRTPG reduced serum TG, TC, LDL-C and liver TG, TC concentrations significantly in hyperlipidemic hamsters. The results of the intestinal microbiota sequencing showed that compared to the control group, LRTPG significantly decreased the relative abundance of the phylum Firmicutes and increased the relative abundance of the phylum Bacteroidetes and Verrucomicrobia (P < 0.01) at the phylum level. At the family level, LRTPG significantly increased the relative abundance of Christensenellaceae, Peptococcaceae, and Verrucomicrobiaceae (P < 0.05 or P < 0.01). At the genus level, LRTPG significantly increased the relative abundance of Oscillospira, Oscillibacter, Flavonifractor and Akkermansiaceae (P < 0.05 or P < 0.01). These changes in the flora were beneficial to the hypolipidemic effect of LRTPG. Conclusion LRTPG may exert its hypolipidemic effect by improving the intestinal flora disorder caused by a high-fat diet in golden hamsters.
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OBJECTIVE@#To compare the role and importance of fibular fixation in tibiofibular fractures by Meta-analysis.@*METHODS@#The literature related to the comparison of the efficacy of fixation of the fibula with or without fixation on the treatment of tibiofibular fractures was searched through the databases of China Knowledge Network, Wipu, Wanfang, The Cochrane Library, Web of science and Pubmed, and statistical analysis was performed using RevMan 5.3 software. The rates of malrotation, rotational deformity, internal/external deformity, anterior/posterior deformity, non-union, infection, secondary surgery and operative time were compared between the fibula fixation and non-fixation groups.@*RESULTS@#A total of 11 publications were included, six randomised controlled trials and five case-control trials, eight of which were of high quality. A total of 813 cases were included, of which 383 were treated with fibula fixation and 430 with unfixed fibulae.Meta-analysis results showed that fixation of the fibulae in the treatment of tibiofibular fractures reduced the rates of postoperative rotational deformity[RR=0.22, 95%CI(0.10, 0.45), P<0.000 1] and internal/external deformity[RR=0.34, 95%CI(0.14, 0.84), P=0.02] and promoted fracture healing [RR=0.76, 95%CI(0.58, 0.99), P=0.04]. In contrast, the rates of poor reduction [RR=0.48, 95% CI(0.10, 2.33), P=0.36], anterior/posterior deformity[RR=1.50, 95%CI(0.76, 2.96), P=0.24], infection[RR=1.43, 95%CI(0.76, 2.72), P=0.27], secondary surgery[RR=1.32, 95%CI(0.82, 2.11), P=0.25], and operative time[MD=10.21, 95%CI(-17.79, 38.21), P=0.47] were not statistically significant (P>0.05) for comparison.@*CONCLUSION@#Simultaneous fixation of the tibia and fibula is clinically more effective in the treatment of tibiofibular fractures.
الموضوعات
Humans , Fibula/surgery , Fractures, Bone/complications , Tibia/surgery , Fracture Healing , Fracture Fixation, Internal , Treatment Outcomeالملخص
AIM To establish an HPLC method for the simultaneous content determination of gallic acid,protocatechuic acid,morroniside,loganin,sweroside,paeoniflorin,hypericin,astragalin,salvianolic acid B,salvianolic acid A,epimedin C and icariin in Bushen Huoxue Sanjie Capsules.METHODS The analysis was performed on a 30℃thermostatic Agilent 5 TC-C18 column(250 mm×4.6 mm,5 μm),with the mobile phase comprising of acetonitrile-0.1%phosphoric acid flowing at 1.0 mL/min in a gradient elution manner,and the detection wavelength was set at 240 nm.RESULTS Twelve constituents showed good linear relationships within their own ranges(r≥0.999 8),whose average recoveries were 97.11%-101.14%with the RSDs of 0.60%-2.65%.CONCLUSION This simple,accurate and reproducible method can be used for the quality control of Bushen Huoxue Sanjie Capsules.
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Drug discrimination is a behavioral pharmacological technique to study the discriminative stimulus effects of drug. Currently drug discrimination has been widely used in preclinical drug development of CNS drugs, the most extensive of which is psychodependent research in the field of drug abuse. This review describes in general the basic principles of drug discrimination, preliminarily elaborates on the relevant characteristics and applications of the subjective effects, time-course effect, stereo specificity, individual differences, and receptor mechanisms, and its development prospects for hallucinogens and cannabis drugs are also presented.
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We wished to establish an expert consensus on late stage of critical care (CC) management. The panel comprised 13 experts in CC medicine. Each statement was assessed based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) principle. Then, the Delphi method was adopted by 17 experts to reassess the following 28 statements. (1) ESCAPE has evolved from a strategy of delirium management to a strategy of late stage of CC management. (2) The new version of ESCAPE is a strategy for optimizing treatment and comprehensive care of critically ill patients (CIPs) after the rescue period, including early mobilization, early rehabilitation, nutritional support, sleep management, mental assessment, cognitive-function training, emotional support, and optimizing sedation and analgesia. (3) Disease assessment to determine the starting point of early mobilization, early rehabilitation, and early enteral nutrition. (4) Early mobilization has synergistic effects upon the recovery of organ function. (5) Early functional exercise and rehabilitation are important means to promote CIP recovery, and gives them a sense of future prospects. (6) Timely start of enteral nutrition is conducive to early mobilization and early rehabilitation. (7) The spontaneous breathing test should be started as soon as possible, and a weaning plan should be selected step-by-step. (8) The waking process of CIPs should be realized in a planned and purposeful way. (9) Establishment of a sleep-wake rhythm is the key to sleep management in post-CC management. (10) The spontaneous awakening trial, spontaneous breathing trial, and sleep management should be carried out together. (11) The depth of sedation should be adjusted dynamically in the late stage of CC period. (12) Standardized sedation assessment is the premise of rational sedation. (13) Appropriate sedative drugs should be selected according to the objectives of sedation and drug characteristics. (14) A goal-directed minimization strategy for sedation should be implemented. (15) The principle of analgesia must be mastered first. (16) Subjective assessment is preferred for analgesia assessment. (17) Opioid-based analgesic strategies should be selected step-by-step according to the characteristics of different drugs. (18) There must be rational use of non-opioid analgesics and non-drug-based analgesic measures. (19) Pay attention to evaluation of the psychological status of CIPs. (20) Cognitive function in CIPs cannot be ignored. (21) Delirium management should be based on non-drug-based measures and rational use of drugs. (22) Reset treatment can be considered for severe delirium. (23) Psychological assessment should be conducted as early as possible to screen-out high-risk groups with post-traumatic stress disorder. (24) Emotional support, flexible visiting, and environment management are important components of humanistic management in the intensive care unit (ICU). (25) Emotional support from medical teams and families should be promoted through"ICU diaries"and other forms. (26) Environmental management should be carried out by enriching environmental content, limiting environmental interference, and optimizing the environmental atmosphere. (27) Reasonable promotion of flexible visitation should be done on the basis of prevention of nosocomial infection. (28) ESCAPE is an excellent project for late stage of CC management.
الموضوعات
Humans , Consensus , Critical Care/methods , Intensive Care Units , Pain/drug therapy , Analgesics/therapeutic use , Delirium/therapy , Critical Illnessالملخص
Tuberculosis (TB) prophylactic therapy for latent infection, which can reduce the risk for the development of active TB, is an important measure in TB control. China recommends prophylactic therapy for latent tuberculosis infection (LTBI) in some key populations to reduce the risk for TB. Contacts of patients with multi-drug and rifampicin-resistant TB (MDR/RR-TB) are at high risk for the infection with drug-resistant pathogen, however, no unified prophylactic therapy regimen has been recommended for LTBI due to exposure to MDR/RR-TB patients. This paper summarizes the current MDR/RR-TB prophylactic therapy regimen and its protection effect based on the results of the retrieval of literature, guidelines, expert consensus and technical specifications to provide reference for the prevention and control of LTBI.
الموضوعات
Humans , Rifampin/therapeutic use , Tuberculosis, Multidrug-Resistant/prevention & control , Tuberculosis/drug therapy , Latent Tuberculosis/chemically induced , China , Antitubercular Agents/therapeutic useالملخص
Objective: To explore the efficacy and safety of percutaneous transluminal pulmonary angioplasty (PTPA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Methods: This prospective single arm study included 19 CTEPH patients (7 male, age(56.3±12.5)years) admitted to Wuhan Asia Heart Hospital from January 2017 to June 2019 and received PTPA interventional therapy. Baseline data, including age, sex, WHO functional class, 6-minute walk distance (6MWD), NT-proBNP, right heart catheterization values, were collected. Patients received single or repeated PTPA. Number of dilated vessels from each patient was analyzed, patients were followed up for 24 weeks and right heart catheterization was repeated at 24 weeks post initial PTPA. All-cause death, perioperative complications, and reperfusion pulmonary edema were reported. WHO functional class, 6MWD, NT-proBNP, right heart catheterization values were compared between baseline and at 24 weeks follow up. Results: Nineteen CTEPH patients received a total of 56 PTPA treatments. The pulmonary artery pressure (mPAP) decreased from (40.11±7.55) mmHg (1 mmHg=0.133 kPa) to (27.53±4.75) mmHg (P<0.001), and the total pulmonary resistance (TPR) decreased from (13.00±3.56) Wood U to (5.48±1.56) Wood U (P<0.001), cardiac output increased from (3.19±0.63) L/min to (5.23±0.94) L/minutes (P<0.01) at 24 weeks post PTPA. The WHO functional class improved significantly (P<0.001), 6MWD increased from (307.08±129.51) m to (428.00±112.64) m (P=0.002), the NT-proBNP decreased at 24 weeks post PTPA (P=0.002). During the follow-up period, there was no death; hemoptysis occurred in 4 patients during the operation, none of which resulted in serious adverse clinical consequences. One patient developed reperfusion pulmonary edema and recovered after treatment. Conclusion: PTPA treatment is safe and can significantly improve the hemodynamics and WHO functional class of patients with CTEPH.
الموضوعات
Adult , Aged , Humans , Male , Middle Aged , Angioplasty , Angioplasty, Balloon , Chronic Disease , Hypertension, Pulmonary/surgery , Prospective Studies , Pulmonary Artery/surgery , Pulmonary Embolism , Treatment Outcomeالملخص
Objective: To investigate the effect of exosomes from mild-inflammation- stimulated human dental pulp stem cells (hDPSC) combined with stromal cell-derived factor-1 (SDF-1) on dental pulp regeneration in rats. Methods: Primary hDPSCs were isolated, cultured and then stimulated by using lipopolysaccharide (LPS). The exosomes from the hDPSCs with (L-EXO) or without (N-EXO) LPS were extracted by overspeed differential centrifugation and were identified by transmission electron microscopy and Western blotting. Forty SD rats, aged 6-8 weeks, were equally divided into S group (SDF-1 alone), L+S group (L-EXO combined with SDF-1), N+S group (N-EXO combined with SDF-1) and blank control group (no substance implanted into the root canal) by random number table method. Bilateral mandibular first molars were used as the experimental teeth to establish pulpless root canal models and different contents were implanted into the root canals according to the groups. All rats were over-anesthetized and sacrificed at the 30th day after content implantation. Bilateral mandibular tissues were taken for histological evaluation by means of HE, Masson and immunohistochemical stainings. Results: The HE staining showed new pulp-like tissue in the root canals of all three experimental groups. The amount of new tissues and the number of cells in the tissues were greatest in L+S group and least in S group. Masson staining showed that the mineralized tissue in L+S group was arranged longitudinally along the root canal wall and the collagen fibers were arranged in an orderly fashion, while those in N+S group showed an irregular and disordered distribution. Quantitative analysis of the area of neovascularization in each group showed that the density of vessels in the L+S group [(2.03±0.65)%] was significantly higher than that in the S group [(0.65±0.05)%] and the N+S group [(1.06±0.38)%] respectively (F=5.879, P<0.05). Immunohistochemical staining showed that the expression of CXC chemokine receptor 4 (CXCR4) was significantly lower in S and L+S groups than in N+S group, with a statistically significant difference (F=8.633, P<0.01). Conclusions: Exosomes secreted by hDPSCs combined with SDF-1 might increase the amount of new tissue in the root canal and the density of blood vessels in the tissue. L-EXO showed a stronger effect than N-EXO did. The combination of L-EXO with SDF-1 might result in more regular arrangement of mineralized tissue and collagen fibers in the regenerative tissues.
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Animals , Humans , Rats , Cell Differentiation , Dental Pulp , Exosomes , Lipopolysaccharides , Rats, Sprague-Dawley , Regeneration , Stem Cells , Stromal Cellsالملخص
Substance addiction is considered to be a chronic recurrent encephalopathy. The neural adap-tation changes induced by addictive substances are partly mediated by epigenetic mechanism. The perma ̄nent changes of gene expression in tissues or brain can be affected by DNA methylation, histone modifica-tion and chromatin remodeling, these changes eventually lead to behavioral abnormalities of individual. Methyl-CpG binding protein 2 (MeCP2), an important transcription inhibitor, contains characteristic do-mains that regulated chromosome conformation, transcription and RNA splicing. It has also been identified that MeCP2 plays an important role in regulating neuronal plasticity and related target gene transcription during brain development, which add more attention about the importance of epigenetic mechanism in neuronal function. Studies have showed that DNA methylation, histone acetylation and phosphorylation regulate MeCP2 gene expression, affect gene and protein transcription, translation and cell regulation in learning, memory and substance addiction. Addictive substances induce psychological and mental dependence, which are related to the changes of neuronal plasticity and gene expression in addictive neural circuits. MeCP2 plays an important role in regulating synaptic transmission and neuronal plasticity in central nervous system. Therefore, it is of great scientific significance to explore the role of MeCP2 in regulating neuronal plasticity in the central nervous system. In this review we summarized the structure and function of MeCP2, the relationship between MeCP2 and epigenetics, and the role of MeCP2 epigenetic modifications induced by different addictive substances in substance addiction, which may provide further understanding of the molecular mechanism of substance addiction and provide new in ̄sight for clinical intervention.
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Chinese medicine injections(CMIs) have higher requirements for quality consistency and controllability than other traditional Chinese medicine products. The implementation of Good Agricultural Practice of Medicinal Plants and Animals(GAP) is an important factor that guarantees the quality stability of raw Chinese medicinal materials and affects the quality of CMIs. Through literature review, data research, expert consultation, and statistical analysis, this paper analyzes the current status of GAP management of key CMIs and the impact of GAP management of raw medicinal materials on the quality consistency and controllability of CMIs. Furthermore, it demonstrates the rationality, necessity, and feasibility of the full implementation of GAP on the basis of CMIs safety re-evaluation.
الموضوعات
Drugs, Chinese Herbal , Injections , Medicine, Chinese Traditional , Plants, Medicinalالملخص
Good agricultural practices(GAP) for Chinese herbal medicine(CHM) is the source of quality control in the production of CHM. To ensure the safety, efficacy, and quality of Chinese herbal and natural medicine, the international community has been exploring the implementation of GAP for CHM. The implementation of GAP for CHM has a far-reaching impact, and the scale planting of CHM has been expanding. However, the medicinal materials produced by the GAP bases for CHM still cannot fully meet the market demand, and the output and quality of CHM remain to be improved. This paper summarizes construction status of GAP bases for CHM.The 129 companies that passed the certification during the implementation of GAP for CHM included 196 GAP bases, forming the scale CHM production zone with Sichuan province, Yunnan province, Jilin province, Henan province, and Shandong province as the core.The total area of GAP bases for CHM in China is about 250 000-500 000 Mu(1 Mu≈667 m2), which is still less than 1% of the total production area of CHM. The international agricultural production quality management strategies are all market-oriented behaviors.Drawing on the international good agricultural and collection practice(GACP) and hazard analysis critical control point(HACCP) as well as the relevant policies of Chinese quality management of CHM, we put forward feasible suggestions for the further implementation of GAP for CHM:(1)The market rules and international experience should be followed and employed to promote GAP management of CHM and third-party implementation of GAP certification;(2)The sound development of GAP for CHM should be boosted with the HACCP management system and the revision of GAP for CHM;(3)The implementation of policies and standards should be stepped up to facilitate the building of a whole-course traceability system for the production of CHM with high quality and reasonable prices.
الموضوعات
Humans , China , Drugs, Chinese Herbal , Hazard Analysis and Critical Control Points , Medicine, Chinese Traditional , Quality Controlالملخص
The effective material basis of Chinese medicine is the key and difficult point in the quality control and modernization research of Chinese medicine. With the increasing application of pharmacophore-based virtual screening in computer-aided drug design, it is possible to employ this technology in the modernization of Chinese medicine. Based on the systematic research method of the pharmacophore model, the present study systematically reviewed the pharmacophore-based technologies and strategies in the identification of active components in Chinese medicine.
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Drug Design , Drugs, Chinese Herbal , Medicine, Chinese Traditionalالملخص
OBJECTIVE@#To evaluate the effects of femtosecond laser treated microgrooved surface on microscopic topography, phase transformation, and three-points flexural strength of zirconia, and to provide reference for surface microstructure optimization of zirconia implant.@*METHODS@#According to different surface treatment methods, 57 computer aided design/computer aided manufacture (CAD/CAM) zirconia bars (20.0 mm×4.0 mm×1.4 mm) were evenly divided into three groups: sintered group, no treatment after sintering, taken as control; sandblasted group, sandblasted with 110 μm aluminium oxide (Al2O3) after sintering; microgrooved group, femtosecond laser fabricated microgrooves with 50 μm width, 30 μm depth, and 100 μm pitch. Surface microscopic topography was observed with scanning electron microscope (SEM) and 3D laser microscope. Further, surface roughness in each group and microgroove size were measured. Crystal phase was analyzed with X-ray diffraction. Specimens were subjected to three- points flexural strength test, and Weibull distribution was used to analyze their strength characteristics.@*RESULTS@#SEM showed that sintered surface was flat with clear grain structure; sandblasted surface exihibited bumps and holes with sharp margins and irregular shape; microgrooves were regularly aligned without evident defect, and nano-scale particles were observed on the surface inside of the microgrooves. Ra value of microgrooved group [(9.42±0.28)] μm was significantly higher than that of sandblasted group [(1.04±0.03) μm] and sintered group [(0.60±0.04) μm], and there was statistical difference between sandblasted group and sintered group (P < 0.001). The microgroove size was precise with (49.75±1.24) μm width, (30.85±1.02) μm depth, and (100.58±1.94) μm pitch. Crystal phase analysis showed that monoclinic volume fraction of sandblasted group (18.17%) was much higher than that of sintered group (1.55%), while microgrooved group (2.21%) was similar with sintered group. The flexural strength of sandblasted group (986.22±163.25) MPa had no statistical difference with that of sintered group (946.46±134.15) MPa (P=0.847), but the strength in microgrooved group (547.92±30.89) MPa dropped significantly compared with the other two groups (P < 0.001). Weibull modulus of sintered, sandblasted, microgrooved groups were 7.89, 6.98, and 23.46, respectively.@*CONCLUSION@#Femtosecond laser was able to form micro/nanostructured microgrooves on zirconia surface, which deleteriously affected the flexural strength of zirconia.
الموضوعات
Humans , Ceramics , Dental Materials , Flexural Strength , Lasers , Materials Testing , Microscopy, Electron, Scanning , Surface Properties , Yttrium , Zirconiumالملخص
Nitrogen fertilizer has been the long-lasting crucial component in cultivation of Chinese materia medica(CMM) and crops for its profound effects on enhancing the productivity. In consideration of its role in better production, intensive and excessive application of N fertilizer is often found in CMM cultivation. Therefore, firstly, this review summarized various concentrations of N application with regards to different CMM and districts from the literatures published in the last two decades. The recommended concentration of nitrogen application of forty seven CMM species were covered in this review. We found that the optimum rates of nitrogen fertili-zer for different medicinal plants species were varied in the range between 0-1 035.55 kg·hm~(-2). Most of the optimum rates of nitrogen fertilizer for CMM in published researches fell between 100-199 kg·hm~(-2). The optimum rate of nitrogen fertilizer is not only related to amount of nitrogen required for different medicinal plants but also to soil fertilities of different fields. In addition, we outlined the diffe-rent effects of proper and excessive nitrogen deposition on yield of CMM. Proper nitrogen deposition benefits the yield of CMM, howe-ver, excessive nitrogen use accounts for a decrease in CMM yield. We elucidated that nutritional content, water use efficiencies, and photosynthesis capacity were major influencing factors. Researches showed that proper nitrogen fertilizer could promote the water use efficiencies of plants and boost photosynthesis. Consequently, the yield of CMM can be enhanced after nitrogen deposition. However, negative effects of nitrogen fertilizer were also found on plant including producing toxic substances to the soil and causing severe pest damages. Lastly we analyzed the impact of N fertilizer application on secondary metabolites which accounts for a large part of active pharmaceutical ingredients of CMM. It usually caused an increase in nitrogen-containing secondary metabolites content and a decrease in non-nitrogen-containing secondary metabolites content respectively. The potential underlying mechanisms are the different synthetic pathways of these metabolites and the plant nutritional status. Synthesis of non-nitrogen-containing secondary metabolites like phenols can be inhibited after nitrogen application because of the competition of the same precursor substances between metabolites synthesis and plant growth. To sum up, impacts and mechanisms of nitrogen fertilizer on yield and quality enhancement of CMM were discussed in this review. Negative effects of excessive nitrogen application on CMM should be paid special attention in CMM cultivation and prescription fertilization based on the field soil quality is strongly recommended. Overall, this review aims to provides insights on improving the proper application of N fertilizer in the cultivation of CMM.
الموضوعات
Agriculture , China , Fertilizers , Materia Medica , Nitrogen/analysis , Soilالملخص
Nitrogen is one of the most frequently used fertilizers in growth of Chinese medicinal plants(CMP). As in many other ecosystems, CMP ecosystem is also composed of plant-herbivore-natural enemy(tritrophic) interactions. Nitrogen fertilizer influences the growth and reproduction of CMP, and it is also able to heavily shape the ecosystem functions of CMP ecosystem through bottom-up forces. Understanding the specific effects of nitrogen fertilizer towards each trophic level will be beneficial to improve the resistance of CMP to herbivore and enhance the control efficiency of nature enemies to herbivore, and eventually, maximize the yield and quality of CMP. Most papers published on nitrogen use in plants focused mainly on the impact of nitrogen fertilization on CMP yield and quality. Influences of nitrogen application on CMP ecosystem get little attention at present. Therefore, this review summed up the potential effects of nitrogen fertilization on CMP ecosystem from perspectives of soil and tritrophic interactions. First of all, nitrogen fertilizer might decrease soil microbial biomass and altered the community structures of soil bacteria, fungi and protozoa. Negative effects of nitrogen fertilizer were found on biodiversity of soil bacteria and protozoa. Different fungi species respond differently to nitrogen fertili-zers. Nitrogen deposition can also decrease the soil pH. Decreases in soil microbial diversity and soil acidification can cause negative effects on CMP growth. In addition, nitrogen fertilizer could regulate the pest resistance of CMP including constitutive and inducible resistance. Both positive and negative effects of nitrogen application were found on pest resistance of CMP. Moreover, the development and predation of natural enemies were influenced by nitrogen deposition. Nitrogen influences natural enemies in many ways including plant volatiles, plant nutrient and structure and the supplementary food quality. Nectar and honeydew of plants and preys serve as important food source for natural enemies especially in early season when preys are still not available. Finally, the interactions between herbivores and their natural enemies were also shaped by nitrogen fertilizer in many aspects like increasing the nutritional content of prey and changing control efficiency of natural enemies. Some herbivores have evolved a strategy to sequester secondary metabolites which they absorbed from plant during their feeding. Studies showed that sequestration efficiency of secondary metabolites in prey could also be regulated by nitrogen. Parasitic, emergence, reproduction rate and longevity of parasites were found positively correlated with nitrogen deposition. Hopefully this study will shed light on practicable and economical application of nitrogen in cultivation of CMP.
الموضوعات
China , Ecosystem , Fertilizers , Nitrogen , Plants, Medicinal , Soilالملخص
Nitrogen fertilizers play an important role in the regulation of plant stress resistance. Impacts of nitrogen fertilizers on abiotic stress resistance and biotic stress resistance of Chinese materia medica(CMM) were summarized in this study. Adequate nitrogen application improves the abiotic stress resistance and weed resistance of CMM, however adverse effect appears when excess nitrogen is used. Generally, pest resistance decreases along with nitrogen deposition, while effects of nitrogen application on disease resistance vary with different diseases. Mechanisms underlying the impact of nitrogen fertilizers on plant stress resistance were also elucidated in this study from three aspects including physical defense mechanisms, biochemistry mechanisms and molecular defense mechanisms. Nitrogen availability modulates physical barrier of CMM like plant growth, formation of lignin and wax cuticle, and density of stomata. Growth of CMM promoted by nitrogen fertilizer may cause some decrease in pest resistance of CMM due to an increase in hiding places for pest along with plant growth. High ambient humidity caused by excessive plant growth facilitates the growth and development of CMM pathogen. Nitrogen application can also interfere with the accumulation of lignin in CMM which makes CMM more vulnerable to pest and pathogen attack. Stomatal closing delays due to nitrogen application is also a causal factor of increasing pathogen infection after nitrogen deposition. Biochemical defenses of plants are mainly achieved through nutrient elements, secondary metabolites, defense-related enzymes and proteins. Nutritional level of CMM and various antioxidant enzymes and resistance-related protein activities are elevated along with nitrogen deposition. These antioxidant enzymes can reduce the damage of reactive oxygen species content produced by plant in response to adversity and therefore enhance stress resistance of CMM. Researches showed that nitrogen application could also cause an increase in nitrogen-containing secondary metabolites content and a decrease in non-nitrogen-containing secondary metabolites content respectively. Nitrogen-mediated molecular defense mechanisms includes multiple plant hormones and nitric oxide signals. Plant hormones related to plant defense like salicylic acid, jasmonic acid and abscisic acid can be modulated by nitrogen application. Negative effect of nitrogen deposition was found on salicylic acid accumulation and the expression of related plant disease resistance genes. However, jasmonic acid level can be elevated by nitrogen. Nitric oxide signals constitute an important part of nitrogen mediated defense mechanisms. Nitric oxide signaling is related to many aspects of plant immunity. The roles of nitrogen fertilizers in CMM stress resistance are complex and may vary with different CMM varieties and environments. Further studies are urgently needed to provide a comprehensive understanding of how to improve stress resistance of CMM by using fertilizers.
الموضوعات
Abscisic Acid , China , Materia Medica , Nitrogen , Plant Growth Regulatorsالملخص
The ecological environment is closely related to the growth and quality of authentic medicinal materials. Ginseng is very strict with its natural environment and grows mostly in the damp valleys of forests, and the appearance and chemical composition of ginseng under different growth environments are very different. This article reviews the effects of different ecological factors(including light, temperature, altitude, moisture, soil factors, etc.)on the appearance and chemical composition(mainly ginsenosides) of ginseng. Through systematic review, it is found that soil physical factors are the most important ecological factors that affect the appea-rance of ginseng, and soil bulk density plays a key role; temperature affects ginsenosides in ginseng medicinal materials The dominant ecological factors for the accumulation of chemical ingredents; strong light, high altitude, high soil moisture, low soil nutrient and strong acid soil can influence the accumulation of secondary metabolites in ginseng. Environmental stress can also stimulate the formation and accumulation of secondary metabolites in medicinal plants. Appropriate low temperature stress, high or low water stress, acid or alkali stress can also promote the accumulation of ginsenosides. This article systematically reviews the ecological factors that affect the appearance and chemical composition of ginseng, and clarifies the dominant ecological factors and limiting factors for the formation of ginseng's appearance and quality, as well as beneficial environmental stress factors, in order to provide a theoretical basis for ginseng ecological planting and ginseng quality improvement.
الموضوعات
Forests , Ginsenosides , Panax , Plants, Medicinal , Soilالملخص
Plants have a memory function for the environmental stress they have suffered. When they are subjected to repeated environmental stress, they can quickly and better activate the response and adaptation mechanism to environmental stress, thus realizing long-term stable reproduction. However, most of the relevant studies are applied to crops and Arabidopsis thaliana rather than medicinal plants about the improvement of plant growth status and the effect on phytoalexin biosynthesis. In this study, yeast extract(YE) was used as an elicitor to simulate biotic stress, and the changes in biomass and the content of some secondary metabolites were measured by giving repeated stresses to Sorbus aucuparia suspension cell(SASC). The results showed that the accumulation levels of biomass and some secondary metabolites in SASC subjected to repeated stress are significantly increased at some time points compared with single stress. A phenomenon that SASC can memorize biotic stress is confirmed in this study and influences phytoalexin accumulation in SASC. Furthermore, the work laid the groundwork for research into the transgenerational stress memory mechanism of medicinal plant.
الموضوعات
Cells, Cultured , Secondary Metabolism , Sorbus , Stress, Physiologicalالملخص
Atractylodis Rhizoma(AR) is a traditional Chinese medicinal material for food and medicine, with the functions of eli-minating dampness, strengthening the spleen, expelling wind evil and dispersing cold. AR contains a variety of compounds, including sesquiterpenoids, alkynes, triterpenoids, aromatic glycosides, polysaccharides and so on. At present, the researches on AR mainly focus on volatile components, with relatively fewer researches on non-volatile components. Polysaccharide from Atractylodis Rhizoma(ARP) is an important material basis among non-volatile components for the efficacy. Due to its many biological activities such as immunomodulatory activity, anti-tumors, anti-virus and anti-oxidation, ARP has certain research value and potential. The diversity of the polysaccharide structure is the basis for biological functions, but it also increases the difficulty of carbohydrate research. The research on the extraction, separation, purification, structure and activity of ARP is in the preliminary exploration stage, still with many shortcomings. Herein, recent advancements in the extraction, purification, structural characteristics and biological activities of ARP were summarized in this article to provide scientific reference for the in-depth systematic research of ARP and the development of AR resources.
الموضوعات
Atractylodes , Drugs, Chinese Herbal , Polysaccharides , Rhizome , Triterpenesالملخص
The present study aimed to explore the effect of nuclear factor erythroid 2 related factor 2(Nrf2)/heme oxygenase-1(HO-1) signaling pathway in intestinal protection by Sishen Pills against ulcerative colitis(UC). After the UC model was induced by 3% dextran sodium sulfate(DSS), experimental animals were randomly divided into control group, model group, salazosulfapyridine(SASP) group, and low-and high-dose Sishen Pills groups. Drug intervention(ig) was performed for seven consecutive days during modeling. On the 7 th day, the mice were euthanized. The body weight and colon length were recorded, and the histopathological changes of the colon were observed by HE staining. Serum interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), total antioxidant capacity(T-AOC), malondialdehyde(MDA), and reactive oxygen species(ROS) were detected by ELISA. The protein and mRNA expression of Nrf2, HO-1, and NADPH quinine oxidoreductase-1(NQO-1) was determined by Western blot and reverse transcription-polymerase chain reaction(RT-PCR). Compared with the normal group, the model group exhibited reduced body weight, colon length, and T-AOC, increased IL-6, TNF-α, MDA, and ROS, and diminished protein and mRNA expression of Nrf2, HO-1, and NQO-1 in the colon tissues. Compared with the model group, the SASP group and high-dose Sishen Pills group showed elevated body weight, colon length, and T-AOC, lowered IL-6, TNF-α, MDA, and ROS levels, and increased protein and mRNA expression of Nrf2, HO-1, and NQO-1 in the colon tissues. As assessed by HE staining, Sishen Pills could improve the pathological changes of the colon. The findings suggested that Sishen Pills could protect the colon against UC induced by 3% DSS. The specific mechanism of action may be related to the anti-inflammatory and anti-oxidative stress effects by the activation of the Nrf2/HO-1 signaling pathway.