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1.
Allium sativum leaf agglutinin (ASAL) binds to several proteins in the midgut of Helicoverpa armigera and causes toxicity. Most of these were glycosylated. Six ASAL-binding proteins were selected for identification. PMF and MS/MS data showed their similarity with midgut aminopeptidase APN2, polycalins and alkaline phosphatase of H. armigera, cadherin-N protein (partial AGAP009726-PA) of Acyrthosiphon pisum, cytochrome P450 (CYP315A1) of Manduca sexta and alkaline phosphatase of Heliothis virescens. Some of the ASAL-binding midgut proteins were similar to the larval receptors responsible for the binding of δ-endotoxin proteins of Bacillus thuringiensis. Galanthus nivalis agglutinin also interacted with most of the ASAL-binding proteins. The ASAL showed resistance to midgut proteases and was detected in the larval hemolymph and excreta. Immunohistochemical staining revealed the presence of ASAL in the body tissue also.  相似文献   
2.
Ganoderma lucidum is widely used as traditional medicine for centuries particularly in China, Japan and Korea. Many bioactive metabolites isolated from G. lucidum were therapeutically active against various diseases. The peptide isolated from water extract of G. lucidum was purified by employing Sephadex G-25, Sephadex G-50 and reverse phase HPLC column chromatography. The antioxidant property of the peptide fractions was determined by various in vitro methods. All fractions obtained from Sephadex G-25 and fraction G from Sephadex G-50 are effective antioxidants and comparably fraction C has the highest antioxidant activity. The molecular weight of purified peptide determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, gel filtration chromatography and Matrix-assisted laser desorption ionization time-of-flight-mass spectrometer was found to be 2.8, 3.34 and 3.35?kDa respectively. The amino acid composition of the peptide was rich in phenylalanine, aspartic acid, proline, histidine and isoleucine. Peptide isolated in the present investigation suggests that has beneficial antioxidant properties may be due to its low molecular weight and specific amino acid composition.  相似文献   
3.
A new nematode species, Philometra terapontis n. sp. (Philometridae), is described from male and female specimens found in the ovary of the jarbua terapon Terapon jarbua (Forsskål) (Terapontidae, Perciformes) from the Bay of Bengal off the eastern coast of India. Based on light and scanning electron microscopical examination, the new species differs from most other gonad-infecting Philometra spp. in the length of the spicules (105–114 μm), a gubernaculum with dorsal, lamella-like structures and a distinct protuberance on its distal end, and a U-shaped, dorsally uninterrupted caudal mound in the male. From a few congeneric, gonad-infecting species with unknown males, it can be distinguished by morphological and biometrical features found in gravid females (i.e. length of body, length of first-stage larvae or oesophagus, and caudal structure), by the host type (fish family) and by the geographical distribution. Philometra terapontis is the first philometrid species reported from a fish belonging to the family Terapontidae. Philometra sawara Quiazon, Yoshinaga &; Ogawa, 2008 is considered a junior synonym of P. scomberomori (Yamaguti, 1935). A key to gonad-infecting species of Philometra parasitising marine and brackish-water fishes is provided.  相似文献   
4.
The emerging paradigm that MSCs are immune privileged has fostered the use of “off-the-shelf” allogeneic MSC-based therapies in human clinical trials. However, this approach ignores studies in experimental animals wherein transplantation of MSCs across MHC boundaries elicits measurable allo-immune responses. To determine if MSCs are hypo-immunogeneic, we characterized the immune response in rhesus macaques following intracranial administration of allogeneic vs. autologous MSCs. This analysis revealed unambiguous evidence of productive allo-recognition based on expansion of NK, B and T cell subsets in peripheral blood and detection of allo-specific antibodies in animals administered allogeneic but not autologous MSCs. Moreover, the degree of MHC class I and II mismatch between the MSC donor and recipient significantly influenced the magnitude and nature of the allo-immune response. Consistent with these findings, real-time PCR analysis of brain tissue from female recipients administered varying doses of male, allogeneic MSCs revealed a significant inverse correlation between MSC engraftment levels and cell dose. Changes in post-transplant neutrophil and lymphocyte counts also correlated with dose and were predictive of overall MSC engraftment levels. However, secondary antigen challenge failed to elicit a measurable immune response in allogeneic recipients. Finally, extensive behavior testing of animals revealed no main effect of cell dose on motor skills, social development, or temperament. Collectively, these data indicate that allogeneic MSCs are weakly immunogenic when transplanted across MHC boundaries in rhesus macaques and this negatively impacts durable engraftment levels. Therefore the use of unrelated donor MSCs should be carefully evaluated in human patients.  相似文献   
5.
Parasites can shape the foraging behaviour of their hosts through cues indicating risk of infection. When cues for risk co-occur with desired traits such as forage quality, individuals face a trade-off between nutrient acquisition and parasite exposure. We evaluated how this trade-off may influence disease transmission in a 3-year experimental study of anthrax in a guild of mammalian herbivores in Etosha National Park, Namibia. At plains zebra (Equus quagga) carcass sites we assessed (i) carcass nutrient effects on soils and grasses, (ii) concentrations of Bacillus anthracis (BA) on grasses and in soils, and (iii) herbivore grazing behaviour, compared with control sites, using motion-sensing camera traps. We found that carcass-mediated nutrient pulses improved soil and vegetation, and that BA is found on grasses up to 2 years after death. Host foraging responses to carcass sites shifted from avoidance to attraction, and ultimately to no preference, with the strength and duration of these behavioural responses varying among herbivore species. Our results demonstrate that animal carcasses alter the environment and attract grazing hosts to parasite aggregations. This attraction may enhance transmission rates, suggesting that hosts are limited in their ability to trade off nutrient intake with parasite avoidance when relying on indirect cues.  相似文献   
6.
Eukaryotes use the process of autophagy, in which structures targeted for lysosomal/vacuolar degradation are sequestered into double-membrane autophagosomes, in numerous physiological and pathological situations. The key questions in the field relate to the origin of the membranes as well as the precise nature of the rearrangements that lead to the formation of autophagosomes. We found that yeast Atg9 concentrates in a novel compartment comprising clusters of vesicles and tubules, which are derived from the secretory pathway and are often adjacent to mitochondria. We show that these clusters translocate en bloc next to the vacuole to form the phagophore assembly site (PAS), where they become the autophagosome precursor, the phagophore. In addition, genetic analyses indicate that Atg1, Atg13, and phosphatidylinositol-3-phosphate are involved in the further rearrangement of these initial membranes. Thus, our data reveal that the Atg9-positive compartments are important for the de novo formation of the PAS and the sequestering vesicle that are the hallmarks of autophagy.  相似文献   
7.
Clusterbean seed health testing is warranted since the pathogen (Xanthomonas campestris pv. cyamopsidis (Xccy)) is seed-borne and seed-transmitted. A polyclonal antibody was developed in rabbit via subcutaneous and intramuscular injections and characterized for sensitivity, specificity and its applicability to ELISA which: (i) was sensitive in detecting as few as 102 cells ml - 1 at a titre of 1: 4000; (ii) was specific, since it reacted only with Xccy and not with other xanthomonads; (iii) reacted both with Xccy cells and culture filtrate, indicating that the antigenic determinant is a secretory component; (iv) was applicable and reliable in seed health testing since it reacted only with infected seeds and plant materials and not with healthy seeds and (v) a purified fraction of antibody was virulent-specific since heat-denatured and avirulent isolates were not detected. The ELISA thus developed is highly reproducible and therefore suitable for the evaluation of the potential disease status of seeds and plant health, which is appropriate for routine seed health testing.  相似文献   
8.
Bacterial wilt caused by Ralstonia (formerly Pseudomonas) solanacearum is worldwide in distribution. It is one of the most destructive bacterial diseases of economically important crops. The serological assays so far developed for the detection of R. solanacearum were able to provide information as to the presence or absence of the pathogen in soil and plant materials. However, they could not discriminate between virulent and avirulent strains of the pathogen and were not specific to strains and races. In the present investigation, virulent bacterial cells (encapsulated with mucin) from tomato seeds were used as antigen and polyclonal antisera were developed in rabbit using a classical immunization protocol. Antisera thus developed were examined for the antibody titre, sensitivity, specificity, rapidity and the efficacy of the antibody in identifying the virulent and avirulent strains of the pathogen and the potential for application of this assay to the screening of infected plant materials and seeds. Our results indicate that the anti-tomato R. solanacearum: (i) has a good antibody titre of 1:10,000; (ii) can detect as few as 100 bacterial cells/ml; (iii) is tomato-specific (it reacted with tomato R. solanacearum, and not with isolates from chilli or eggplant); (iv) is reactive to all isolates of R. solanacearum from tomato; (v) is not cross-reactive with non-pseudomonads; (vi) is virulent strain-specific as it recognizes the virulent exopolysaccharide component as an antigenic determinant; (vii) reactivity could be correlated well with the degree of infection in tomato seeds and plant materials. The enzyme linked immunosorbent assay developed is sensitive, specific and rapid, therefore suitable for the detection of R. solanacearum isolates from tomato seeds during routine assays.  相似文献   
9.
Because of the ability to manipulate their genome, mice are the experimental tool of choice for many areas of scientific investigation. Moreover, established experimental mouse models of human disease are widely available and offer a valuable resource to obtain proof-of-concept for many cell-based therapies. Nevertheless, efforts to establish reliable methods to isolate mesenchymal stromal cells (MSCs) from mouse bone marrow have been elusive. Indeed, a variety of physical and genetic approaches have been described to fractionate MSCs from other cell lineages in bone marrow, but few have achieved high yields or purity while maintaining the genomic integrity of the cells. We provide a historic overview of published procedures dedicated to the isolation of mouse MSCs from bone marrow and compact bone. We also review current findings indicating that growth-restrictive conditions imposed by atmospheric oxygen promotes immortalization of mouse MSCs and how expansion in a low-oxygen environment enhances cell yields and maintains genomic stability. Finally, we provide basic recommendations for isolating primary mouse MSCs and discuss potential pitfalls associated with these isolation methods.  相似文献   
10.
Distinctions between isobaric residues have been a major challenge in mass spectrometric peptide sequencing. Here, we propose a methodology for distinction among isobaric leucine, isoleucine, and hydroxyproline, a commonly found post-translationally modified amino acid with a nominal mass of 113 Da, through a combined electron transfer dissociation-collision-induced dissociation approach. While the absence of c and z(?) ions, corresponding to the Yyy-Xxx (Xxx = Leu, Ile, or Hyp) segment, is indicative of the presence of hydroxyproline, loss of isopropyl (Δm = 43 Da) or ethyl radicals (Δm = 29 Da), through collisional activation of z radical ions, are characteristic of leucine or isoleucine, respectively. Radical migration processes permit distinctions even in cases where the specific z(?) ions, corresponding to the Yyy-Leu or -Ile segments, are absent or of low intensity. This tandem mass spectrometric (MS(n)) method has been successfully implemented in a liquid chromatography-MS(n) platform to determine the identity of 23 different isobaric residues from a mixture of five different peptides. The approach is convenient for distinction of isobaric residues from any crude peptide mixture, typically encountered in natural peptide libraries or proteomic analysis.  相似文献   
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