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1.
Shengmai (SM) formula, a classical traditional Chinese medicine formula, is composed of Panax ginseng (Pg), Ophiopogon japonicus (Oj), and Schisandra Chinesis (Sc). SM has been clinically used to treat heart failure and ischemic heart disease. Although SM formula has been reported to be potential for fighting against Alzheimer’s disease (AD) by previous works, there are many gaps in our knowledge on its usage in AD treatment on an organism level and will then need to be further clarified. In this study, transgenic Caenorhabditis elegans expressing human Aβ1–42 are used to evaluate SM formula efficacy to treat AD phenotype and to investigate its underlying mechanism. The results showed that SM formula ameliorated AD pathological characteristics of paralysis behavior and chemotaxis defect in transgenic Celegans. With SM treatment, the number of Aβ deposits decreased, the levels of gene expressions of hsp16-2, hsp16-41, ace-1, ace-2, and TNFA1P1 homolog genes were down-regulated. Our results also showed that Oj exhibited more stronger effect on delaying paralysis in worms than Pg and Sc did, and synergistic action was observed between Pg and Oj, and Sc further enhanced the activity of Pg/Oj combination on delaying paralysis behavior. Further, SM with herbs of Pg, Oj, and Sc at a dose proportion of 9:9:6 exhibited superior therapeutic efficacy in comparison with herbs at other dose proportions. After SM formula extracted by ethanol, it delayed AD symptoms on a wider dose from 0.2 to 10.0 mg/mL with no toxic effect. These results provided more evidence for SM formula being potential to be used to treat AD.  相似文献   

2.

Background  

In C. elegans there are two well-defined TGFβ-like signaling pathways. The Sma/Mab pathway affects body size morphogenesis, male tail development and spicule formation while the Daf pathway regulates entry into and exit out of the dauer state. To identify additional factors that modulate TGFβ signaling in the Sma/Mab pathway, we have undertaken a genetic screen for small animals and have identified kin-29.  相似文献   

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4.
Substantial evidence suggests that the aggregation of amyloid-β (Aβ) peptide into fibrillar structures that is rich in β-sheets is implicated as the cause of Alzheimer’s disease. Therefore, an attractive therapeutic strategy is to prevent or alter Aβ aggregation. Phenolic compounds are natural substances that are composed of one or more aromatic phenolic rings and present in wine, tea, fruits, vegetables and a wide variety of plants. In this work, we investigated the effects of ferulic acid, morin, quercetin and gossypol against Aβ aggregation. From the ThT and turbidity assays, it is observed that in addition to the fibril aggregate, another type of aggregate is formed in the presence of morin, quercetin, and gossypol. On the other hand, ferulic acid did not prevent fibril formation, but it did appear to reduce the average length of fibrils compared to Aβ alone. To study the protective effects of phenolic compounds on Aβ-induced toxicity, we utilized the nematode Caenorhabditis elegans (C. elegans) as an in vivo model organism, human Aβ is expressed intracellularly in the body wall muscle. We found that exposure of Caenorhabditis elegans to ferulic acid give more protection against Aβ toxicity than morin, quercetin and gossypol.  相似文献   

5.

Background  

The presence of β-lactamases in Y. enterocolitica has been reported to vary with serovars, biovars and geographical origin of the isolates. An understanding of the β-lactamases in other related species is important for an overall perception of antibiotic resistance in yersiniae. The objective of this work was to study the characteristics of β-lactamases and their genes in strains of Y. intermedia and Y. frederiksenii, isolated from clinical and non-clinical sources in India.  相似文献   

6.
An interspecific cross (BC 1) involving a species with one of the largest genomes in the Coffea genus [Coffea heterocalyx (HET), qDNA = 1.74 pg] and a species with a medium-sized genome [Coffea canephora (CAN), qDNA = 1.43 pg] was studied using two types of molecular markers, AFLP and SSR. One hundred and eighty eight AFLP bands and 34 SSR primer pairs were suitable for mapping. The total map length was 1,360 cM with 190 loci distributed in 15 linkage groups. The results were compared to those obtained previously on an interspecific BC 1 progeny involving a species with a medium-sized genome (Coffea liberica var dewevrei, DEW) and a species with one of the smallest genomes (Coffea pseudozanguebariae, PSE). They are discussed relative to three main points: (1) the relevance of the different marker types, (2) the genomic distribution of AFLP and SSR markers, and (3) the relation between AFLP polymorphism and genome size.Communicated by H.F. Linskens  相似文献   

7.
The lipase Lip2 of the edible basidiomycete, Pleurotus sapidus, is an extracellular enzyme capable of hydrolysing xanthophyll esters with high efficiency. The gene encoding Lip2 was expressed in Escherichia coli TOP10 using the gene III signal sequence to accumulate proteins in the periplasmatic space. The heterologous expression under control of the araBAD promoter led to the high level production of recombinant protein, mainly as inclusion bodies, but partially in a soluble and active form. A fusion with a C-terminal His tag was used for purification and immunochemical detection of the target protein. This is the first example of a heterologous expression and periplasmatic accumulation of a catalytically active lipase from a basidiomycete fungus.  相似文献   

8.
Using yeast genome databases and literature data, we have conducted a phylogenetic analysis of pectinase PGU genes from Saccharomyces strains assigned to the biological species S. arboricola, S. bayanus (var. uvarum), S. cariocanus, S. cerevisiae, S. kudriavzevii, S. mikatae, S. paradoxus, and hybrid taxon S. pastorianus (syn. S. carlsbergensis). Single PGU genes were observed in all Saccharomyces species, except S. bayanus. The superfamily of divergent PGU genes has been documented in S. bayanus var. uvarum for the first time. Chromosomal localization of new PGU1b, PGU2b, and PGU3b genes in the yeast S. bayanus var. uvarum has been determined by molecular karyotyping and Southern hybridization.  相似文献   

9.

Background  

C. elegans TGF-β-like Sma/Mab signaling pathway regulates both body size and sensory ray patterning. Most of the components in this pathway were initially identified by genetic screens based on the small body phenotype, and many of these mutants display sensory ray patterning defect. At the cellular level, little is known about how and where these components work although ray structural cell has been implicated as one of the targets. Based on the specific ray patterning abnormality, we aim to identify by RNAi approach additional components that function specifically in the ray lineage to elucidate the regulatory role of TGF-β signaling in ray differentiation.  相似文献   

10.
11.
Dana Bernátová 《Biologia》2008,63(2):175-176
The paper brings information on an isolated occurrence and morphological characters of Carex × involuta and C. juncella populations in the Vel’ká Fatra Mts. Their presence has been known neither from the territory of Slovakia nor from the whole Western Carpathians till now.  相似文献   

12.
Molecular genetic analysis of melibiose-fermenting Saccharomyces strains isolated from fermentative processes and natural sources in different world regions was conducted to deduce the evolutionary diversity of Saccharomyces yeasts and find new α-galactosidase MEL genes. The species S. bayanus, S. mikatae, and S. paradoxus were shown to have a single copy of MEL and not accumulate polymeric genes, unlike some S. cerevisiae populations. The polymeric genes MELp1 and MELp2 were identified in S. paradoxus for the first time. Genes identical by 98.7% are located on the chromosomes X and VI, respectively. Phylogenetic analysis indicates that MEL genes of the Saccharomyces yeasts are species-specific.  相似文献   

13.
The molecular mechanism of the unique cis to trans isomerization of unsaturated fatty acids in the solvent-tolerant bacterium Pseudomonas putida S12 was studied. For this purpose, the carbon isotope fractionation of the cistrans isomerase was estimated. In resting cell experiments, addition of 3-nitrotoluene for activation of the cistrans isomerase resulted in the conversion of the cis-unsaturated fatty acids into the corresponding trans isomers. For the conversion of C16:1 cis to its corresponding trans isomer, a significant fractionation was measured. The intensity of this fractionation strongly depended on the rate of cistrans isomerization and the added concentration of 3-nitrotoluene, respectively. The presence of a significant fractionation provides additional indication for a transition from the sp2 carbon linkage of the cis-double bond to an intermediate sp3 within an enzyme–substrate complex. The sp2 linkage is reconstituted after rotation to the trans configuration has occurred. As cytochrome c plays a major role in the catabolism of Cti polypeptide, these findings favour a mechanism for the enzyme in which electrophilic iron (Fe3+), provided by a heme domain, removes an electron of the cis double bond thereby transferring the sp2 linkage into sp3.  相似文献   

14.
Root segments from seedlings of Panax ginseng produced adventitious roots directly when cultured on 1/2 MS solid medium lacking NH4NO3 and containing 3.0 mg l−1 IBA. Using this adventitious root formation, we developed rapid and efficient transgenic root formation directly from adventitious root segments in P. ginseng. Root segments were co-cultivated with Agrobacterium tumefaciens (GV3101) caring β-glucuronidase (GUS) gene. Putative transgenic adventitious roots were formed directly from root segments on medium with 400 mg l−1 cefotaxime and 50 mg l−1 kanamycin. Kanamycin resistant adventitious roots were selected and proliferated as individual lines by subculturing on medium with 300 mg l−1 cefotaxime and 50 mg l−1 kanamycin at two weeks subculture interval. Frequency of transient and stable expression of GUS gene was enhanced by acetosyringon (50 mg l−1) treatment. Integration of transgene into the plants was confirmed by the X-gluc reaction, PCR and Southern analysis. Production of transgenic plants was achieved via somatic embryogenesis from the embryogenic callus derived from independent lines of adventitious roots. The protocol for rapid induction of transgenic adventitious roots directly from adventitious roots can be applied for a new Agrobacterium tumefaciens-mediated genetic transformation protocol in P. ginseng.  相似文献   

15.
We undertook a field study to determine whether comb cell size affects the reproductive behavior of Varroa destructor under natural conditions. We examined the effect of brood cell width on the reproductive behavior of V. destructor in honey bee colonies, under natural conditions. Drone and worker brood combs were sampled from 11 colonies of Apis mellifera. A Pearson correlation test and a Tukey test were used to determine whether mite reproduction rate varied with brood cell width. Generalized additive model analysis showed that infestation rate increased positively and linearly with the width of worker and drone cells. The reproduction rate for viable mother mites was 0.96 viable female descendants per original invading female. No significant correlation was observed between brood cell width and number of offspring of V. destructor. Infertile mother mites were more frequent in narrower brood cells.  相似文献   

16.
Verbena (Verbena x hybrida), an important floricultural species, was successfully regenerated from stem segments on Murashige and Skoog's basal medium supplemented with thidiazuron and indole-3-acetic acid. A transformation system was developed using cvs. Temari Scarlet, Temari Sakura, Tapien Rose and TP-P2. Agrobacterium tumefaciens strain Agl0 harboring the sGFP gene was infected into stem segments. Transformation efficiency was improved by evaluating and manipulating the age of the plant material, the concentration of kanamycin in the medium during selection, and the length of the culture period in the dark. After 2-3 months of culture on the selection medium, GFP-positive shoots were obtained in all four of the cultivars tested. These shoots were successfully acclimated and set flowers within 2-3 months in a greenhouse. GFP was expressed in all of the organs including the floral parts. Stable genomic transformation was confirmed by Southern blot analysis. No morphological differences were observed between the transformed plants and their host plants.  相似文献   

17.
Recombinant Zantedeschia aethiopica agglutinin (ZAA) was expressed in Escherichia coli as N-terminal His-tagged fusion. After induction with isopropylthio-β-d-galactoside (IPTG), the recombinant ZAA was purified by metal-affinity chromatography. The purified ZAA protein was applied in anti-fungal assay and the result showed that recombinant ZAA had anti-fungal activity towards leaf mold (Fulvia fulva), one of the most serious phytopathogenic fungi causing significant yield loss of crops. This study suggests that ZAA could be an effective candidate in genetic engineering of plants for the control of leaf mold.  相似文献   

18.
Scyphozoan medusae are very successful foragers which occasionally occur in high abundances in boreal waters and may impact many different groups in the marine ecosystem by means of a variety of toxins. A rainbow trout gill cell line, RTgill-W1, was tested for its suitability as quantitative indicator of the cytotoxicity of Cyanea capillata and Aurelia aurita; the major scyphozoan species in the North and Baltic seas. Cultures of rainbow trout gill cells were exposed to whole venoms extracted from fishing tentacles and oral arms at increasing protein concentrations. The venom caused detachment, clumping and lysis of cells, as well as a drop in vitality, in a dose-dependent manner. Morphological changes in the cells were evident within 1 h after venom addition. The damage to gill cells was quantified by measuring the metabolic activity of the cells by means of the fluorescence of resorufin derived from the nonfluorescent substrate, resazurin. In general, a decrease in the metabolic activity of the cells was detected at a venom (protein) concentration above 2.0 μg ml−1 (corresponding to 0.2 μg 104 cells−1), and a total loss of activity was observed above 40.0 μg ml−1 (corresponding to 4.0 μg 104 cells−1). C. capillata venoms had increased cytotoxic activity as compared to A. aurita venoms at the same concentration. Cnidocyst extracts from oral arms of A. aurita induced an 85% loss of gill cell viability at concentrations of 0.2 μg 104 cells−1, whereas crude venoms from fishing tentacles reduced cell viability by 18% at the same concentration. Gel electrophoresis of the venoms indicated that these consist of a large number of proteins in a fairly wide size range, from 6 to 200 kDa, including some that are the same size as those found in cubomedusae. It also appears that larger (i.e., older) medusae have more complex venoms and, in some cases, more potent venoms than smaller animals.  相似文献   

19.
Zygotic embryos at different developmental stages were tested for their potential in the initiation of embryogenic suspensor mass (ESM) lines using immature seeds of Pinus rigida × P. taeda. The highest frequency (1.1%) of ESM was obtained with explants from cones collected on July 1. All excised embryos of the July 1 collection were at the early proembryo stage. Two different culture media were compared. Forty-eight ESM lines were initiated on Pinus taeda basal medium (P6) (0.97%) with 13.5 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 4.4 μM benzyladenine (BA). However, only four ESM were obtained on a modified Murashige and Skoog medium (MSG; 0.55%). Most of the ESM arose from the seeds that were at the stages ranging from late cleavage polyembryony to the early staged proembryo. Out of 52 lines (0.46%) that were produced from 11,388 explants, only two viable lines (0.018%) (PRT11 and PRT28) survived. As for somatic embryo maturation, the highest number (224/g−1 FW) of matured cotyledonary somatic embryos (line PRT 28) was obtained on a medium containing 100 μM abscisic acid (ABA), 0.2 M maltose, and 1.2% gellan gum. For germination of the somatic embryos, the cotyledonary somatic embryos derived from maturation medium were transferred on half-strength Litvay medium (LM) plus 0.4% gellan gum. The germination rates were high (71.4–96.3%) regardless of the concentrations of either ABA or gellan gum in the maturation medium. Approximately 500 somatic plants were recovered from the germination medium and transferred to the green house; finally most of them were transplanted successfully to the experimental field.  相似文献   

20.
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