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1.
The efficacy of submicron chitosan dispersions (SCD) on Alternaria alternata rot of the ‘Lingwu changzao’ jujube (Zizyphus jujuba Mill. cv. Lingwu changzao) fruit and possible mechanisms involved were investigated in this study. When jujube fruit at the preharvest stage were sprayed twice with SCD (10 mg/ml) water solution and then natural infections were allowed to develop, there was a significant reduction in disease incidence and lesion index compared to control fruit during storage period, and similar results were obtained from postharvest fruit inoculated with the Alternaria rot pathogen. Scanning electron microscopy of the pathogen revealed that hyphae and spores were damaged and deformed when growing on the surface of fruit pretreated with SCD or CHO. The slowed softening of jujube fruit resulted from the protopectin content increasing compared with the control. Furthermore, SCD sprays inhibited cell wall hydrolysing enzymes, pectinase activity was decreased, and the increase in cellulase activity was postponed (from 30 days to 45 days).It was concluded that preharvest application of SCD was a more effective alternative to conventional chitosan for preventing postharvest from Alternaria rot of ‘Lingwu changzao’ jujube fruit.  相似文献   

2.
The formation of fat‐laden foam cells, which contributes to the fatty streaks in the plaques of atheromas, is an important process in atherosclerosis. Vascular smooth muscle cells (VSMCs) are a critical origin of foam cells. However, the mechanisms that underlie VSMC foam cell formation are not yet completely understood. Here, we demonstrated that oxidized low‐density lipoprotein (oxLDL) inhibited lipophagy by suppressing lipid droplet (LD)‐lysosome fusion and increased VSMC foam cell formation. Moreover, although oxLDL treatment inhibited lysosomal biogenesis, it had no significant effect on lysosomal proteolysis and lysosomal pH. Notably, through TMT‐based quantitative proteomic analysis and database searching, 94 differentially expressed proteins were identified, of which 54 were increased and 40 were decreased in the oxLDL group compared with those in the control group. Subsequently, SCD1, a protein of interest, was further investigated. SCD1 levels in the VSMCs were down‐regulated by exposure to oxLDL in a time‐dependent manner and the interaction between SCD1 and LDs was also disrupted by oxLDL. Importantly, SCD1 overexpression enhanced LD‐lysosome fusion, increased lysosomal biogenesis and inhibited VSMC foam cell formation by activating TFEB nuclear translocation and its reporter activity. Modulation of the SCD1/TFEB‐mediated lipophagy machinery may offer novel therapeutic approaches for the treatment of atherosclerosis.  相似文献   

3.
A biological control of crown rot disease of banana fruit was analysed using an integrated approach combining hot water treatment and Trichoderma harzianum strain DGA01. Treated fruits were stored at 22–25 °C and 90–95% relative humidity for 2 weeks. The bioefficacy of fungal antagonist in vitro towards crown rot-causing pathogens, namely Lasiodiplodia theobromae, Thielaviopsis paradoxa, Colletotrichum musae and Fusarium verticillioides, was enhanced by 11.41% following hot water treatment (50 °C, 20 min). DGA01 germinated on the fruit 48 h after inoculation and parasitised the pathogen. Postharvest application showed that hot water treatment and conidial suspension of DGA01 (106 ml?1) applied singly performed significantly better than the untreated control in reducing the incidence of crown rot, but were not as effective as the fungicide. The combination of hot water treatment and DGA01 gave 93% control of fruit decay which was comparable with fungicide treatment of 95%. The quality of fruit was markedly improved in hot water treatment + DGA01 as compared to those dipped in fungicide solution. The inconsistencies of single treatments, by DGA01 or hot water dips, in controlling crown rot such as variation in severity of disease among treatments and within a treatment, were lessened by dipping the fruit in DGA01 conidial suspension following hot water treatment.  相似文献   

4.
We have hypothesized a state of zinc deficiency in sickle cell disease (SCD). This could at least partially explain the growth problems, hypogonadism, and slow healing leg ulcers associated with SCD. Preliminary findings revealed abnormally low red blood cell zinc levels in 10 of 16 patients studied. Before suggesting zinc supplementation in SCD we thought it important to look at the effect of zinc on red cell metabolism and function. It was found that zinc chloride added to normal and SCD blood to a final concentration of 1.5 × 10?3 M caused a left-shift of the blood oxygen affinity curve (increased oxygen affinity) varying from 1.5 to 3.5 mm Hg change in half saturation (p50). This curve shifting property has important implications for SCD since recent work with cyanate suggests that such shifts are very beneficial in treatment of SCD. Thus zinc supplementation in SCD, in addition to its potential role in correcting wound healing and growth problems, may have a beneficial effect on the basic pathological process. Data are given which suggest that zinc and 2, 3-diphosphoglycerate may not be competing for the same site on the hemoglobin molecule.  相似文献   

5.
Fruit grey mould, caused by the fungus Botrytis cinerea, is known to be a harmful disease of strawberry at postharvest stage. However, effects of an application of biological control agents (BCAs) on strawberry fruit in terms of shift in the microbial community are still unknown. The present research aimed to investigate the effects of an application of BCAs on postharvest microbial populations present on strawberry fruits. Strawberry plants were sprayed with three kinds of BCA, RhizoVital 42 fl. (Bacillus amyloliquefaciens FZB42), Trianum‐P (Trichoderma harzianum T22) and Naturalis (Beauveria bassiana ATCC 74040), targeting Botrytis cinerea fungus. Control plots were composed of water and fungicide treatments. Microbial communities (bacteria and fungi) were analysed via next‐generation sequencing on an Illumina MiSeq. Analysis of 16S RNA and ITS rRNA sequences indicated that the BCAs application modified both bacterial and fungal community compositions and diversity. An application of two BCAs together had more effects on microbial community composition than a single application. These results suggest that BCAs can modify bacterial and fungal community composition and diversity on strawberry fruits, which may consequently improve the efficiency and establishment of these products on control of postharvest diseases of fruits, such as grey mould.  相似文献   

6.
Implementation of model‐based practices for process development, control, automation, standardization, and validation are important factors for therapeutic and industrial applications of human pluripotent stem cells. As robust cultivation strategies for pluripotent stem cell expansion and differentiation have yet to be determined, process development could be enhanced by application of mathematical models and advanced control systems to optimize growth conditions. Therefore, it is important to understand both the potential of possible applications and the apparent limitations of existing mathematical models to improve pluripotent stem cell cultivation technologies. In the present review, the authors focus on these issues as they apply to stem cell expansion processes. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:355–364, 2017  相似文献   

7.
Induced pluripotent stem cells (iPS) can differentiate into cardiomyocytes (CM) and represent a promising form of cellular therapy for heart regeneration. However, residual undifferentiated iPS derivates (iPSD), which are not fully eliminated by cell differentiation or purification protocols, may form tumors after transplantation, thus compromising therapeutic application. Inhibition of stearoyl-coA desaturase (SCD) has recently been reported to eliminate undifferentiated human embryonic stem cells, which share many features with iPSD. Here, we tested the effects of PluriSin#1, a small-molecule inhibitor of SCD, on iPS-derived CM. We found that plurisin#1 treatment significantly decreased the mRNA and protein level of Nanog, a marker for both cell pluripotency and tumor progression; importantly, we provide evidence that PluriSin#1 treatment at 20 µM for 1 day significantly induces the apoptosis of Nanog-positive iPSD. In addition, PluriSin#1 treatment at 20 µM for 4 days diminished Nanog-positive stem cells in cultured iPSD while not increasing apoptosis of iPS-derived CM. To investigate whether PluriSin#1 treatment prevents tumorigenicity of iPSD after cell transplantation, we intramyocardially injected PluriSin#1- or DMSO-treated iPSD in a mouse model of myocardial infarction (MI). DMSO-treated iPSD readily formed Nanog-expressing tumors 2 weeks after injection, which was prevented by treatment with PluriSin#1. Moreover, treatment with PluriSin#1 did not change the expression of cTnI, α-MHC, or MLC-2v, markers of cardiac differentiation (P > 0.05, n = 4). Importantly, pluriSin#1-treated iPS-derived CM exhibited the ability to engraft and survive in the infarcted myocardium. We conclude that inhibition of SCD holds the potential to enhance the safety of therapeutic application of iPS cells for heart regeneration.  相似文献   

8.
Sister chromatids of metaphase chromosomes can be differentially stained if the cells have replicated their DNA semiconservatively for two cell cycles in a medium containing 5-bromodeoxyuridine (BrdU). When prematurely condensed chromosomes (PCC) are induced in cells during the second S phase after BrdU is added to the medium, the replicated chromosome segments show sister chromatid differential (SCD) staining. Employing this PCC-SCD system on synchronous and asynchronous Chinese hamster ovary (CHO) cells, we have demonstrated that the replication patterns of the CHO cells can be categorized into G1/S, early, early-mid, mid-late, and late S phase patterns according to the amount of replicated chromosomes. During the first 4 h of the S phase, the replication patterns show SCD staining in chains of small chromosome segments. The amount of replicated chromosomes increase during the mid-late and late S categories (last 4 h). Significantly, small SCD segments are also present during these late intervals of the S phase. Measurements of these replicated segments indicate the presence of characteristic chromosome fragment sizes between 0.2 to 1.2 m in all S phase cells except those at G1/S which contain no SCD fragments. These small segments are operationally defined as chromosome replicating units or chromosomal replicons. They are interpreted to be composed of clusters of molecular DNA replicons. The larger SCD segments in the late S cells may arise by the joining of adjacent chromosomal replicons. Further application of this PCC-SCD method to study the chromosome replication process of two other rodents, Peromyscus eremicus and Microtus agrestis, with peculiar chromosomal locations of heterochromatin has demonstrated an ordered sequence of chromosome replication. The euchromatin and heterochromatin of the two species undergo two separate sequences of decondensation, replication, and condensation during the early-mid and mid-late intervals respectively of the S phase. Similar-sized chromosomal replicons are present in both types of chromatin. These data suggest that mammalian chromosomes are replicated in groups of replicating units, or chromosomal replicons, along their lengths. The organization and structure of these chromosomal replicons with respect to those of the interphase nucleus and metaphase chromosomes are discussed.  相似文献   

9.
目的 应用统计过程控制理论分析指导医院服务质量持续改进。方法 联合使用多个控制图方法对医院服务质量评价指标的变化趋势进行监控,及时发现过程中的异常波动,制定针对性措施实施过程改进。结果 找出了影响医院服务质量数据波动的主要原因,制定改进措施,取得了良好的管理效果。结论 控制图可以准确全面反映医院服务质量的总体情况和过程控制情况,根据数据异常分布状态找到潜在的影响服务质量的原因并进行持续改进,是有效的过程管理工具。  相似文献   

10.
11.
Sexual cell division (SCD) that produces two gametangial cells from one vegetative mother cell is the first step observed morphologically in the sexual reproduction in the Closterium peracerosum–strigosum– littorale complex. SCD‐inducing activities specific for each mating‐type cells were detected in the medium in which both mating type cells has been cocultured. Mating‐type minus (mt ? ) cells released SCD‐inducing substance specific for mating‐type plus (mt + ) cells and were designated as SCD‐ inducing pheromone (IP)‐minus, whereas mt ? specific substances released from mt + cells were designated as SCD‐IP‐plus. Culture medium was subjected to gel filtration, and then SCD‐IP‐plus and SCD‐IP‐minus chemical were found to have the molecular masses of 90–100 kDa and 10–20 kDa, respectively. It was evident that light was imperative for this type of signaling. Gametangial cells of both mating types were obtained from vegetative cells by treatment with SCD‐IPs. Gametangial mt + cells showed high competency for conjugation with vegetative mt ? cells, whereas gametangial mt ? cells showed low competency for conjugation with vegetative mt + cells. These results indicate that SCD in both mating type cells is induced by high molecular weight sex pheromones and that the roles of gametangial cells in the process of conjugation differ by sex.  相似文献   

12.

Objective:

Stearoyl‐coenzyme A desaturase‐1 (SCD1) is a key enzyme in fatty acid and energy metabolism. Increased hepatic SCD1 activity is associated with obesity and obesity‐related diseases. We examined the relations of two plasma SCD activity indices (16:1n‐7/16:0, 18:1n‐9/18:0) with body composition, and the association of lifestyle and dietary variables with the plasma SCD indices.

Design and Methods:

This population‐based, cross‐sectional study of 2021 elderly (71–74 y) men and women from the Hordaland Health Study in Western Norway was conducted using a validated food frequency questionnaire, body composition measurements by dual‐energy X‐ray absorptiometry and determination of the plasma fatty acid profile.

Results:

In multivariate regression analyses, plasma SCD indices were positively associated with BMI and body fat (P < 0.001 for both). From the 2.5th to 97.5th percentiles of plasma SCD‐16 and SCD‐18 indices, fat mass differed by about 8 kg and 5 kg, respectively. Intake of polyunsaturated fatty acids were negatively associated with SCD‐16 (partial r = ?0.30) and SCD‐18 (partial r = ?0.24) (P < 0.001 for both). Alcohol intake was positively associated with SCD‐16 (partial r = 0.26) and SCD‐18 (partial r = 0.16) (P < 0.001 for both), whereas coffee consumption and physical activity were inversely associated with SCD‐16 (P = 0.026 and P = 0.006, respectively) and SCD‐18 (P = 0.001 and P = 0.022, respectively).

Conclusions:

In this elderly population, plasma markers of SCD1 activity are associated with increased adiposity. Furthermore, modifiable dietary habits and lifestyle are associated with plasma SCD indices. These results suggest that SCD1 activity may be a promising target for weight control.
  相似文献   

13.
Cordylophora caspia is a hydrozoan which causes biofouling in power plants and is an increasing problem in UK drinking water treatment works. Thermal control is not usually feasible without a ready source of hot water so laboratory experiments were conducted to assess whether using pulsed doses of chlorine is an alternative solution. C. caspia polyps disintegrated after a single 20 min dose (the length of one backwash cycle in water treatment work filter beds) of 2.5 ppm chlorine. Without further treatment colonies regenerated within 3 days, but repeated dosing with chlorine for 20 min each day inhibited this regeneration. The resistance of surviving colonies to chlorine increased over time, although colony size and polyp regeneration continued to fall. These results suggest pulsed treatment with chlorinated backwashes at 2 ppm could be used to control C. caspia biofouling in rapid gravity filters and this may have relevance to other settings where thermal control is not feasible.  相似文献   

14.
We identified four cDNA sequences encoding sheep homologues of the CD1 molecule. The sheep sequences were selected from λgt11 thymocyte cDNA libraries by hybridization with a humanCD1C probe and a homologous sheep probe. TheSCD1B-42 andSCD1A25 sequences encode complete CD1 molecules. The third sequence,SCD1B-52, which is closely related toSCD1B-42 and may be an allele, has the sequence encoding the α3 region precisely deleted. The fourth sequence,SCD1T10, is truncated at the 5′ end. All four sequences are related to the humanCD1B and domestic rabbitCD1B-like sequences at both nucleotide and amino acid level. Comparison of the derivedCD1 amino acid sequences with the sequence of major histocompatibility complex class I molecules showed that the sheep CD1 molecules, like human CD1 molecules, lack most of the conserved class I residues known to be involved in interaction with 132-microglobulin and the CD8 molecule. They do not contain the peptide docking residues involved in anchoring peptides in the peptide binding groove of class I molecules. Southern hybridization of sheep DNA with a sheepCD1 exon 4/ga3 probe showed that the sheep genome encodes at least sevenCD1 genes. The implications of these analyses for CD1 function are discussed. The nucleotide sequence data reported in this paper have been submitted to the EMBL/GenBank nucleotide sequence databases and have been assigned the accession numbers Z36890 (SCD1A25), Z36891 (SCD1B-42), Z36892 (SCD1B-52), and X90567 (SCDIT10)  相似文献   

15.
Musca domestica is a major problem in poultry production where management has relied mostly on pesticides, which eventually have led to the development of widespread resistance in insect populations and environmental contamination. In this study, we explored the use of entomopathogenic fungi for the control of houseflies in Brazil. A total of 10 isolates of different fungal pathogens were tested on the larval stages of M. domestica, which were originally derived from a commercial aviary. Among the test fungi, Metarhizium anisopliae (sensu stricto) CG46 and CG30 were the most virulent isolates, causing up to 60% mortality at day 10, but only CG46 was selected for a field trial as it attained higher sporulation on larval cadavers. A commercial product based on the M. anisopliae isolate ESALQ-1037 (Metarril®) was also field-tested using standard treatment procedures. After spraying both fungi in the aviary manure, there was a significant reduction (twofold lower) in adult density of M. domestica captured per trap compared to the control shed. Therefore, our results indicate that M. anisopliae is a promising biological control agent for M. domestica larvae, but new strategies for fungal application and appropriate formulation need to be developed to improve its effectiveness in poultry environments.  相似文献   

16.
The ability of a rhizobacterium to protect tomato plants against naturally occurring diseases as well as to improve crop yield under field conditions was studied. The rhizobacterium was introduced to the plants through seed microbiolization. Treatments consisted of different frequencies of fungicide (Chlorothalonyl) sprayings (5, 10 or 20 applications) of tomato plants grown from either microbiolized or non‐microbiolized seeds over a 90‐day evaluation period. Treatment of non‐microbiolized seeds without fungicide application was included as a control. The progress of the following three naturally occurring diseases was evaluated in the field and quantified: early blight (Alternaria solani), late blight (Phytophthora infestans), and septoria leaf spot (Septoria lycopersici). All treatments resulted in reduced disease severity when compared with the control treatment. Highest final fruit yields were found after treatment of plants grown from non‐microbiolized seeds and sprayed with fungicide 20 times over 90 days, and for treatment of plants from microbiolized seeds that received 10 fungicide spray applications, although all treatments increased yield over that obtained in the control treatment. The results demonstrate that combined rhizobacterial and chemical treatments in the field may permit reducing fungicidal spraying frequency while at the same time increasing crop yields.  相似文献   

17.
Absence of stearoyl-CoA desaturase-1 (SCD1) in mice leads to chronic inflammation of the skin and increased susceptibility to atherosclerosis, while also increasing plasma inflammatory markers. A recent report suggested that SCD1 deficiency also increases disease severity in a mouse model of inflammatory bowel disease, induced by dextran sulfate sodium (DSS). However, SCD1-deficient mice are known to consume increased amounts of water, which would also be expected to increase the intake of DSS-treated water. The aim of this study was to determine the effect of SCD1 deficiency on DSS-induced acute colitis with DSS dosing adjusted to account for genotype differences in fluid consumption. Wild-type controls were treated with 3.5% DSS for 5 days to induce moderately severe colitis, while the concentration of DSS given to SCD1-deficient mice was lowered to 2.5% to control for increased fluid consumption. Colonic inflammation was assessed by clinical and histological scoring. Although SCD1-deficient mice consumed a total intake of DSS that was greater than that of wild-type controls, colonic inflammation, colon length and fecal blood were not altered by SCD1-deficiency in DSS-induced colitis, while diarrhea and total weight loss were modestly improved. Despite SCD1 deficiency leading to chronic inflammation of the skin and increased susceptibility to atherosclerosis, it does not accelerate inflammation in the DSS-induced model of acute colitis when DSS intake is controlled. These observations suggest that SCD1 deficiency does not play a significant role in colonic inflammation in this model.  相似文献   

18.
Antimicrobial-resistant pathogens in the environment and wastewater treatment systems, many of which are also important pollutant degraders and are difficult to control by traditional disinfection approaches, have become an unprecedented treat to ecological security and human health. Here, we propose the adoption of genetic editing techniques as a highly targeted, efficient and simple tool to control the risks of environmental pathogens at the source. An ‘all-in-one’ plasmid system was constructed in Aeromonas hydrophila to accurately identify and selectively inactivate multiple key virulence factor genes and antibiotic resistance genes via base editing, enabling significantly suppressed bacterial virulence and resistance without impairing their normal phenotype and pollutant-degradation functions. Its safe application for bioaugmented treatment of synthetic textile wastewater was also demonstrated. This genetic-editing technique may offer a promising solution to control the health risks of environmental microorganisms via targeted gene inactivation, thereby facilitating safer application of water treatment biotechnologies.  相似文献   

19.
AIMS: To characterize polyfermenticin SCD, a newly identified bacteriocin of Bacillus polyfermenticus SCD. METHODS AND RESULTS: Bacillus polyfermenticus SCD was identified as a bacteriocin producer with a bactericidal activity against Bacillus subtilis IFO 12113. Polyfermenticin SCD, named tentatively as the bacteriocin produced by B. polyfermenticus SCD, showed a narrow spectrum of activity against Gram-positive and Gram-negative bacteria, a yeast and moulds. Production of polyfermenticin SCD in a 5 l jar fermenter followed typical kinetics of primary metabolite synthesis. The antibacterial activity of polyfermenticin SCD on sensitive indicator cells disappeared completely by treatment with proteinase K, which indicates its proteinaceous nature. Polyfermenticin SCD seemed to be very stable throughout the pH range of 2.0 to 9.0, and it was relatively heat labile compared with other bacteriocins. Direct detection of polyfermenticin SCD activity on SDS-PAGE suggested that it had an apparent molecular mass of about 14.3 kDa. CONCLUSIONS: Bacillus polyfermenticus SCD produced relatively heat-labile polyfermenticin SCD with a narrow spectrum of activity. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacillus polyfermenticus SCD is a commercial probiotic which has been used for the treatment of long-term intestinal disorders. New findings on polyfermenticin SCD will be valuable in the evaluation of commercial probiotics. Polyfermenticin SCD can be used to control Bacillus spoilage organisms as a biological control agent.  相似文献   

20.
基于水敏性城市设计的城市水环境污染控制体系研究   总被引:2,自引:0,他引:2  
随着城市化进程加快,自然地表被硬化的不透水地面所替代,城市面源污染加剧,城市水环境恶化成为限制城市发展的关键因素。水敏性城市设计(Water Sensitive Urban Design,WSUD)提出从城市设计和生态管理角度实现城市发展与水环境保护的共同目标。综述了WSUD理论内涵、设计原则、技术体系以及隐含在其中的生态学思想,提出当前WSUD理论发展需要进一步完善的技术体系,整合生态学思想以及建立科学的效益评估方法,并与传统生态智慧关联,为WSUD在我国的发展和研究提供科学参考。同时,基于WSUD技术及蕴含于其中的生态智慧,针对三峡库区城市水环境特点和城市面源污染特征,兼顾城市景观优化、生物生境再造、生态服务功能优化与城市建设协同发展,采取生态缓冲、湿地消纳和自然调控相结合的综合防控思路,以水陆界面生态屏障综合控制为主线,根据城市生活区-休闲娱乐区-水陆界面缓冲区3个空间层次,提出城市污染源头-滨湖绿带-生态护坡-基塘湿地-自然消落带多重拦截和消纳的城市水环境污染控制体系,形成三峡库区水敏性城市设计与建设的模版和参考,为三峡库区城市水体污染控制提供科学依据,促进三峡库区水质保护与城市人居环境协同发展。  相似文献   

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