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131.
Immunoglobulin (Ig)-containing plasma cells in the Harderian gland in broiler and native chickens of Bangladesh 总被引:1,自引:0,他引:1
The distribution and frequency of immunoglobulin (Ig)-containing plasma cells, their variations due to sex, and the mode of secretion of Ig cells into the duct system of the Harderian gland was investigated in broiler and native chickens of both sexes in Bangladesh. The Harderian gland is covered by a capsule, and the connective tissue septa divide the gland into numerous unequal-sized numerous lobes and lobules. The Ig-containing plasma cells were located in the interstitial space, interacinar space, apical part of the lobule, and lumina of the lobules of the Harderian gland in both broiler and native chickens. The population of these Ig-containing plasma cells varied in between broiler and native chickens, and also between male and female broiler and native chickens. In the broiler, the number of IgM-containing plasma cells was higher; in contrast, in the native chickens, the population of IgA-containing plasma cells was larger. In the broiler, there were more IgA- and IgG-containing plasma cells in the male; in contrast, there were more IgM-containing plasma cells in female. In native chickens the frequency of IgA-containing plasma cells was greater in the female than male. When the data for broiler and native birds were compared, it was found that there were significantly more IgA- and IgG-containing plasma cells in the native male and female chickens than in the broiler males and females. The secretory Igs were located in the lumina of acini and the duct system of the Harderian gland. In the present study Ig-containing plasma cells were observed to be released in the lumina of the lobules of Harderian gland by the breakdown of acinar tissues in broilers, and by holocrine mode of secretion in the native chicken. These results suggested that the Harderian gland, even though it is not a lymphoid organ as a whole, but acts as an immunopotent organ in chickens, and that the gland in native chicken contains more Ig-containing plasma cells due to their scavenging. 相似文献
132.
Basil Sansom 《Anthropological Forum》2007,17(1):71-92
Australia's Native Title Act 1993 (Cth) allows Indigenous Australians to lay claims to traditional country located on unalienated Crown land. The Act also admits claims to compensation for the loss of traditional country that has been appropriated and made subject to freehold or other forms of tenure. The Yulara case discussed here was historically important. It was the first case mounted to determine appropriate compensation for the extinguishment of native title. In a compensation claim, the Indigenous applicants must first establish that (taken together) they are both (i) the rightful heirs to ancestral holders of native title and (ii) that they still maintain the traditions and customs of their forebears (phase 1). Once their holding of native title has been established at law, the applicants may then enter their claim to monetary compensation for the ‘extinguishment’ of their native title over designated lands (phase 2). In the Yulara case, it was found that the applicants were not constituted as a group of recognisable native title holders whose rights to country were rooted in those traditional laws and customs that obtained when the Yulara lands were officially brought under the dominion of British authorities ‘at sovereignty’ (1824). The case could not, therefore, proceed to a hearing of the compensation phase. Eight issues concerning the proper performance of the anthropologist as expert witness in native title matters were raised by the trial judge in the Yulara case. This paper deals with the bearing of the judge's observations on those anthropological representations that may be made in future native title cases. 相似文献
133.
Timothy R. Johnson Scott L. Stewart Daniela Dutra Michael E. Kane Larry Richardson 《Plant Cell, Tissue and Organ Culture》2007,90(3):313-323
Eulophia alta (Linnaeus) Fawcett & Rendle seeds collected from the Florida Panther National Wildlife Refuge (Collier County, FL; FPNWR)
were used in a screen of five asymbiotic orchid seed germination media to determine their effectiveness in promoting germination
and protocorm development. In addition, 10 fungal isolates collected from the roots of E. alta at sites in the FPNWR, Highlands County (FL), and Goethe State Forest (Levy County, FL; GSF), and a fungal isolate from the
roots of Spiranthes brevilabris collected from GSF were screened for their effectiveness at promoting in vitro symbiotic germination of E. alta seeds. After 18 weeks asymbiotic culture, seeds sown on PhytoTechnology Orchid Seed Sowing Medium germinated to a higher percentage (87.9%) and had a higher percentage of protocorms with
developing protomeristems (32.7%) than seeds cultured on Knudson C, Malmgren Modified Terrestrial Orchid Medium, ?-strength
Murashige & Skoog, or Vacin & Went Modified Orchid Medium. Significantly more leaf-bearing protocorms were observed on PhytoTechnology Orchid Seed Sowing Medium (0.8%) and Vacin & Went Modified Orchid Medium (1.3%) than other media tested. Of the
fungi tested, one fungal isolate (Ealt-396) promoted germination to 69.0%, two isolates promoted germination to less than
0.75% and did not support further protocorm development, and eight isolates did not support germination. Seeds co-cultured
in darkness with Ealt-396 grew more rapidly than asymbiotic seedlings following germination. In addition, co-cultured (=symbiotic)
seedlings continued to develop more rapidly than asymbiotic seedlings upon transfer to 16/8 h light/dark photoperiod. Symbiotic
seed culture of E. alta may be a more desirable method of propagation since protocorms develop more rapidly than seeds sown on asymbiotic media.
Symbiotic seedlings may be more appropriate for reintroduction to natural areas than asymbiotic seedlings since symbiotic
seedlings could serve to inoculate soils with a germination promoting mycobiont. 相似文献
134.
Gomez G Mansouraty G Gardea J Narayan M 《Biochemical and biophysical research communications》2007,364(3):561-566
Curcumin, the major constituent of turmeric is a known antioxidant. We have examined the oxidative folding of the model four-disulfide-bond-containing protein bovine pancreatic ribonuclease A (RNase A) in its presence; results indicate that RNase A regeneration rate increases in a curcumin-dependent manner. Examination of the native tendency of the fully-reduced polypeptide and the stability of key folding intermediates suggests that the increased oxidative folding rate can be attributed to native-like elements induced within the fully-reduced polypeptide and the stabilization of native-like species by this non-redox-active natural product. Our results provide a template for the design of curcuminoid-based synthetic small-molecule fold catalysts that accelerate the folding of ER-processed proteins; this assumes significance given that nitrosative stress and dysfunction of the ER-resident oxidoreductase protein disulfide isomerise due to S-nitrosylation are factors associated with the pathogenesis of Alzheimer’s and Parkinson’s diseases. 相似文献
135.
The serotonin1A receptor is an important member of the G-protein coupled receptor family, and is involved in a variety of cognitive, behavioral, and developmental functions. None of the subtypes of G-protein coupled serotonin receptors have yet been purified to homogeneity from natural sources. We report here, for the first time, the solubilization of human serotonin1A receptors stably expressed in neuronal (HN2) cells. Importantly, ligand binding assay shows that the serotonin1A receptor solubilized this way is functionally active. The effective solubilization of the serotonin1A receptor from neuronal cells represents an important step toward the purification of the receptor in native-like membrane environment. 相似文献
136.
《Médecine Nucléaire》2022,46(3):156-163
BackgroundNative valve endocarditis (NVE) is a rare but serious disease. The prognosis depends on the rapidity of diagnosis, and is currently based on modified Duke criteria, where echocardiography has a key role but may lack sensitivity if valves are calcified. For prosthetic valves, the European Society of Cardiology 2015 recommendations added 18F-FDG PET/CT as a major imaging criterion as well as for extension assessment. This study evaluated the diagnostic accuracy of 18F-FDG PET/CT in NVE and in extension assessment.MethodsThis retrospective study involved 59 patients suspected of NVE at Bordeaux university hospital between 2011 and 2019 and received 18F-FDG PET/CT. The final diagnosis was established according to Duke criteria after 3 months of management. Infective endocarditis (IE) was assessed in the initial phase according to the Duke criteria. All PET/CTs were blindly reviewed jointly by a junior and senior nuclear-medicine physician.ResultsIn total, 59 patients were included. At 3 months, 26 patients had definite IE, 22 had rejected IE, and 11 possible IE. Twelve patients had positive PET/CT results. The sensitivity of the modified Duke criteria in the initial phase was 77% and the specificity was 81%. When combined with 18F-FDG PET/CT, the sensitivity of the Duke criteria increased to 96% and the specificity was 81%. The sensitivity of 18F-FDG PET/CT alone was 46%. All three patients with perivalvular abscess had positive PET/CT results. Of the 22 patients with NVE definite at 3 months, fourteen (54%) had at least one septic embolism diagnosed on PET/CT.ConclusionsThe implementation of 18F-FDG PET/CT with modified Duke criteria increased the sensitivity for NVE diagnosis in the initial phase and contributed to IE extension assessment. It may contribute to making the diagnosis of a local cardiac complication. 相似文献
137.
In addition to its high affinity for antibody Fc domains, staphylococcal Protein A has been shown to bind certain Fab domains. We investigated this in order to develop a small, recombinant Protein A-binding alternative to immunoglobulin G (IgG) from nanobodies, single-domain antibodies derived from a camelid variant IgG’s variable region. We engineered a nanobody with affinity solely for Protein A as well as a dimerized version of higher affinity for typical multidomain Protein A constructs. Because this recombinant nanobody can be immobilized using a cleavable crosslinker, it has proven to be suitable for the isolation and mild elution of protein complexes in native conditions. 相似文献
138.
Elshaima M. Fawzi María Elena González-SánchezMaría Jesús Corral Montserrat CuquerellaJosé M. Alunda 《International journal for parasitology》2014
A somatic protein from adult Haemonchus contortus (Hc23), the most abundant component in a low molecular weight fraction with known immunizing effect against experimental haemonchosis, has been purified by immunochromatography. The immunoprophylactic value of Hc23 was tested in groups of 5–6 months old Assaf lambs using Al(OH)3 or Escherichia coli lipopolysaccharide + inactivated Propionibacterium acnes as adjuvant and the results compared with uninfected control, uninfected and challenged or infected and challenged lambs. Immunization with Hc23 in either adjuvant elicited significant reductions in fecal egg counts after challenge with 15,000 L3s (70.67%–85.64%, respectively) and reduced (67.1% and 86%) abomasal worm counts (45 days post-challenge). Immunized lambs displayed higher peripheral eosinophil counts, were less anaemic and had weight gains than challenged controls. The results suggest that the Hc23 antigen can induce a partially protective response against haemonchosis in lambs. 相似文献
139.
140.