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31.
Rose K Curtis J Baldwin T Mathis A Kumar B Sakthianandeswaren A Spurck T Low Choy J Handman E 《International journal for parasitology》2004,34(6):655-664
This is the first report of cutaneous leishmaniasis in kangaroos where infection was acquired within Australia. The diagnosis is based on the clinical criteria used for humans, the lesion histopathology, the detection and isolation of parasites from the lesions, and the analysis of the small subunit ribosomal RNA genes using the polymerase chain reaction. Despite a clear indication that the parasites belong to the genus Leishmania, no assignation to a known Leishmania species could be made using these or other less conserved genetic loci such as the non-transcribed spacer of the mini-exon repeat. As is the case in humans, some but not all animals harbouring lesions had antibodies to the isolated parasites or to several other Leishmania species. The isolated parasites displayed two well characterised Leishmania glycoconjugates, the lipophosphoglycan and proteophosphoglycan. They were infectious for mouse macrophages in vitro and established long-term infection at 33 degrees C but not at 37 degrees C. Our findings raise the possibility of transmission to humans, which may be unrecognised and suggest the possibility that imported species of Leishmania could become endemic in Australia. 相似文献
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The 17-residue transmembrane domain of beta-galactoside alpha 2,6- sialyltransferase is sufficient for Golgi retention 总被引:10,自引:6,他引:10 下载免费PDF全文
beta-Galactoside alpha 2,6-sialyltransferase (ST) is a type II integral membrane protein of the Golgi apparatus involved in the sialylation of N-linked glycans. A series of experiments has shown that the 17-residue transmembrane domain of ST is sufficient to confer localization to the Golgi apparatus when transferred to the corresponding region of a cell surface type II integral membrane protein. Lectin affinity chromatography of chimeric proteins bearing this 17-residue sequence suggests that these chimeric proteins are localized in the trans-Golgi cisternae and/or trans-Golgi network. Further experiments suggest that this 17-residue sequence functions as a retention signal for the Golgi apparatus. 相似文献
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It has been found that tissues fixed for electron microscopy and dehydrated in acetone can be embedded in mixtures of n-butyl methacrylate and polyester resin. Activation with 1 per cent tert-butyl hydroperoxide followed by 12 to 48 hours at 60°C produces blocks that section well with glass knives. The ribbons are cleared of methacrylate by heat (200–250°C for 1 hour) and/or immersion in organic solvents (CCL4, acetone-ether). After removal of the methacrylate the residual polyester matrix provides thermostable and insoluble support for the tissue. Its insolubility permits staining by immersion of cleared preparations in organic solvents carrying heavy metal compounds in solution. Clearing by heat stabilizes section-grid relationships. The removal of volatile materials by clearing substantially reduces contamination of both specimen and microscope. Tissue fine structure is well preserved in these preparations. 相似文献
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Sandra L. Gage Stanley R. Keim Jay R. Simon Walter C. Low 《Neurochemical research》1994,19(11):1379-1386
The cholinergic projections from basal forebrain nuclei to the retrosplenial cortex (RSC) have previously been studied using a variety of histological approaches. Studies using acetylcholinesterase (AChE) histochemistry and choline acetyltransferase (ChAT) immunocytochemistry have demonstrated that this projection travels via the cingulum on route to the RSC. Preliminary studies from our laboratory, however, have shown that the fornix may also be involved in this projection. The present study uses the combination of pathway lesions, and the analysis of cholinergic neurochemical markers in the RSC to determine the role of the fornix in the cholinergic projection to the RSC. High affinity choline uptake (HACU) and ChAT activity were measured in the RSC of control rats, animals with cingulate lesions, and animals with fornix plus cingulate lesions. Fornix plus cingulate lesions resulted in significant deceases in HACU and ChAT activity in comparison to cingulate lesions alone. Muscarinic receptor binding was also evaluated in combination with the various lesions, and a significant increase in retrosplenial receptor binding was noted following fornix lesions. Together, these results support the concept of a fornix-mediated cholinergic pathway to the RSC. 相似文献
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Feeding behavior, in an ad libitum situation on potato plants in the laboratory, was continuously observed for approximately 7 h/day on 2 successive days for 18 adult femaleLeptinotarsa decemlineata. Additional behaviors were also recorded including resting, walking, biting, local movements, grooming, defecating, and regurgitating. These data were used to calculate a time budget for the various behaviors. The feeding data were analyzed to describe the structure of feeding for young adult females on their normal host plant. The criterion for a meal (minimum intermeal interval) was determined to be 286 s. This criterion was used to distinguish between intra- and intermeal interruptions in feeding for all subsequent analyses. Meals taken from leaves that were young, medium aged, or old did not differ, but on average beetles took 60% of their meals from young leaves. Meal size and meal duration were equally good predictors of when a meal would end. Feeding from stems was a prominent feature for most beetles. The stem meals had much longer durations than leaf meals, but stem feeding did not affect subsequent leaf feeding. The structure of feeding by these beetles is compared with that found in other insects, especiallyLocusta migratoria. 相似文献
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Gupta Achla Gullapalli Srinivas Pan Hui Ramos-Ortolaza Dinah L. Hayward Michael D. Low Malcom J. Pintar John E. Devi Lakshmi A. Gomes Ivone 《Cellular and molecular neurobiology》2021,41(5):1103-1118
Cellular and Molecular Neurobiology - Activation of μ, δ, and κ opioid receptors by endogenous opioid peptides leads to the regulation of many emotional and physiological responses.... 相似文献
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Parasites may influence the outcome of interspecific competition between closely related host species through lower parasite virulence in the host with which they share the longer evolutionary history. We tested this idea by comparing the prevalence of avian malaria (Haemosporidia) lineages and their association with survival in pied and collared flycatchers (Ficedula hypoleuca and F. albicollis) breeding in a recent contact zone on the Swedish island of Öland. A nested PCR protocol amplifying haemosporidian fragments of mtDNA was used to screen the presence of malaria lineages in 1048 blood samples collected during 6 years. Competitively inferior pied flycatchers had a higher prevalence of blood parasites, including the lineages that were shared between the two flycatcher species. Multistate mark–recapture models revealed a lower survival of infected versus uninfected female pied flycatchers, while no such effects were detected in male pied flycatchers or in collared flycatchers of either sex. Our results show that a comparatively new host, the collared flycatcher, appears to be less susceptible to a local northern European malarial lineage where the collared flycatchers have recently expanded their distribution. Pied flycatchers experience strong reproductive interference from collared flycatchers, and the additional impact of species‐specific blood parasite effects adds to this competitive exclusion. These results support the idea that parasites can strongly influence the outcome of interspecific competition between closely related host species, but that the invading species need not necessarily be more susceptible to local parasites. 相似文献
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