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1.
Charles D. Derby David N. Blaustein 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1988,163(6):777-794
1. | In order to understand the functional organization of the crustacean olfactory system, we are using intracellular recording and staining techniques to correlate the structure and function of single, odorant-sensitive interneurons in the brain of the crayfishProcambarus clarkii. We describe here the anatomy and physiology of interneurons that connect the brain with the medullae terminales or other eyestalk ganglia. |
2. | All of the interneurons in our study (Table 1, Figs. 3–15) are at least third-order olfactory neurons (second-order olfactory interneurons) because they respond to chemostimulation of the olfactory organ (the antennules) but do not branch in the olfactory lobe (the neuropil to which primary olfactory receptor cells of the antennules project). |
3. | Much of the central nervous system, including the three main divisions of the brain (protocerebrum, deuterocerebrum, tritocerebrum) (Fig. 1) and the medullae terminales (Fig. 2), are involved in integrating olfactory or multimodal (including olfactory) information, since these areas contain neurites of olfactory interneurons. Previous studies have indicated that regions involved in such processing include the olfactory lobes and accessory lobes of the deuterocerebrum, and regions I, II, IV, and VII (in some species) of the medullae terminales. Our results show that also prominent among regions involved in olfactory or multimodal (including olfactory) integration are the anterior and posterior optic neuropils of the protocerebrum (Figs. 3–11, 14, 15), the lateral and medial antennular neuropils of the deuterocerebrum (Figs. 3, 4, 7), the tegumentary neuropils (Figs. 3, 4, 8, 11) and the antennal neuropils (Figs. 3–5) of the tritocerebrum, and neuropils III, VI, XII of the medullae terminales (Figs. 12, 13). |
4. | These olfactory interneurons were sensitive to chemostimulation (unimodal), chemo- and mechanostimulation (bimodal), or chemo-, mechano-, and photostimulation (trimodal) (Table 1). Responses could be excitatory or inhibitory, even for a given neuron (Table 1). Morphologically complex interneurons (those having bilateral branching) were more likely to have complex response characteristics (trimodal sensitivity) (Figs. 8–12) than were morphologically simpler interneurons (those having unilateral branching) (Figs. 3–7, 14, 15). Olfactory interneurons with a soma in the medulla terminalis showed the most complex response profiles: they were trimodal, and were excited by odorants but were inhibited by touch and/or light (Figs. 12, 13). This finding suggests that these are complex, high order interneurons. |
5. | Our studies reveal that olfactory and other sensory information is transmitted between the brain and the medullae terminales (and possibly other eyestalk ganglia) by a coactivated, parallel array of structurally and functionally diverse neurons. |
2.
Rearing techniques and results of preliminary host range tests are reported forHadena perplexa (Denis & Schiffermuller) (Lep.: Phalaenidae) a candidate biocontrol agent against the weed bladder campion,Silene vulgaris (Moench) Garcke, in Manitoba, Canada. In the laboratory, it was necessary to pipette a 15% honey solution in water into the
flowers as food for the adult moths. When reared singly to avoid cannibalism, 56% of the 1st instar larvae developed to pupae. Larvae fed on a natural diet for 10 days can then be reared on either one of 2 artificial
diets. Choice oviposition tests and no-choice larval feeding tests were conducted with plant species closely related toS. vulgaris in the generaSilene, Dianthus, Gypsophila, Lychnis, Saponaria. Species in 4 of 5 of these genera were accepted for oviposition, and species in all 5 genera supported the development of
1st instar larvae to the pupal stage.H. perplexa should not be introduced into Canada.
相似文献
3.
4.
Patterns of Root Colonization in Epacridaceous Plants Collected from Different Sites 总被引:2,自引:0,他引:2
Root colonization was studied in ten species of the Epacridaceaeat three sites in Victoria by morphological and cross-inoculationexperiments. The sites and genera chosen were Cranbourne [Epacrisimpressa Labill. andLeucopogon ericoides(Smith) R. Br.] andRye [L. parviflorus(Andrews) Lindley] on the Mornington Peninsula,and the Grampians[Astroloma conostephioides(Sond.) Benth.,A.humifusum(Cav.) R. Br.,A pinifolium(R. Br.) Benth,Brachylomadaphnoides(Smith) Benth.,E. impressa, E. impressavar.grandifloraBenth.andStyphelia adscendensR. Br.] in western Victoria. For morphologicalstudies, samples of roots from each species at each site werecleared and stained and examined microscopically. For cross-inoculationstudies, cuttings from each site were struck in potting mediuminoculated with soil from the same and other sites. The ericoidmycorrhizae in the roots of plants found at or grown in Cranbourneand Rye soils were similar. Both were significantly differentfrom the internal hyphae found in the roots of plants foundat or grown in Grampians soils, which were three times largerin diameter and formed dense coils which filled the host celland invaded adjacent epidermal cells. This suggests that morethan one fungus is involved in the relationships, that the MorningtonPeninsula sites had a different fungus from the Grampians siteand that host specificity is low. Vesicular structures werealso found commonly on plants at the Grampians site, in contrastwith other sites. Epacridaceae; root; fungus; mycorrhiza; morphology; inoculation 相似文献
5.
Background
The aims of the study were to examine the association between CKD and the metabolic syndrome (MetS) and its components in older adults. We also explored two possible pathways linking the metabolic syndrome with CKD: inflammation as measured by high sensitivity C-Reactive Protein (hsCRP) and insulin resistance as measured by HOMA-IR.Methods
Community-dwelling non-diabetic 70+ adults from the Einstein Aging Study participated in the study. We defined CKD as eGFR below 60mL/min/1.73m2. MetS was defined according to recent guidelines from the National Cholesterol Education Program. Binary logistic regressions were used to assess the association between the metabolic syndrome, its components and CKD with adjustments for demographics, HOMA-IR and hsCRP.Results
Of 616 participants (mean age = 79.3 years, 65.5% female), 25% had MetS and 26.5% had CKD. Participants with CKD had a significantly higher prevalence of the MetS than individuals without CKD (34.4% vs. 24.3%). Binary logistic regression models showed that CKD was associated with MetS (OR = 1.72, 95%CI = 1.13–2.61). The association was unaltered by adjustment for hsCRP but altered by adjustment for HOMA-IR. As the number of MetS components increased the relative odds of CKD also increased. None of the individual components was independently associated with CKD.Conclusion
MetS is associated with CKD in non-diabetic older adults. Results showed that as the number of MetS components increased so did the odds for CKD. HOMA-IR seems to be in the casual pathway linking MetS to CKD. 相似文献6.
Andréia S Lessa Bruno D Paredes Juliana V Dias Adriana B Carvalho Luiz Fernando Quintanilha Christina M Takiya Bernardo R Tura Guilherme FM Rezende Antonio C Campos de Carvalho Célia MC Resende Regina CS Goldenberg 《BMC veterinary research》2010,6(1):1-10
Background
Atypical scrapie was first identified in Norwegian sheep in 1998 and has subsequently been identified in many countries. Retrospective studies have identified cases predating the initial identification of this form of scrapie, and epidemiological studies have indicated that it does not conform to the behaviour of an infectious disease, giving rise to the hypothesis that it represents spontaneous disease. However, atypical scrapie isolates have been shown to be infectious experimentally, through intracerebral inoculation in transgenic mice and sheep. The first successful challenge of a sheep with 'field' atypical scrapie from an homologous donor sheep was reported in 2007.Results
This study demonstrates that atypical scrapie has distinct clinical, pathological and biochemical characteristics which are maintained on transmission and sub-passage, and which are distinct from other strains of transmissible spongiform encephalopathies in the same host genotype.Conclusions
Atypical scrapie is consistently transmissible within AHQ homozygous sheep, and the disease phenotype is preserved on sub-passage. 相似文献7.
van Beers JJ Raijmakers R Alexander LE Stammen-Vogelzangs J Lokate AM Heck AJ Schasfoort RB Pruijn GJ 《Arthritis research & therapy》2010,12(6):R219
Introduction
Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology. 相似文献8.
9.
Habituation of western gorillas to human presence is generally an expensive, lengthy and difficult process. Here we describe the habituation process for two groups of western gorillas at the Mondika Research Center, with the hope that the lessons we learned will facilitate future gorilla studies. We expand upon earlier studies by describing the process through complete habituation for both males and females, and for more than one group. The major obstacle to habituation was developing sufficient tracking skills to follow gorilla trail on a daily basis. Once this was achieved, the silverback became semi-habituated (i.e. ignoring human presence during half of contacts) within a year, although the majority of group females continued to avoid humans. As female presence at contacts increased, a period of male recidivism followed, requiring an additional year before his complete habituation was reached. Habituating the females took longer than the male, but we found, contrary to earlier studies, that it consisted of the same stages, including avoidance, aggression, and curiosity before habituation. We compare results between groups and across sites and discuss how factors such as tracking abilities, group size and cohesion, population density and home range overlap, and the manner of approaching gorillas during contacts influence the habituation process. 相似文献
10.
Sidders B Withers M Kendall SL Bacon J Waddell SJ Hinds J Golby P Movahedzadeh F Cox RA Frita R Ten Bokum AM Wernisch L Stoker NG 《Genome biology》2007,8(12):R265-13
We describe an analysis, applicable to any spotted microarray dataset produced using genomic DNA as a reference, that quantifies prokaryotic levels of mRNA on a genome-wide scale. Applying this to Mycobacterium tuberculosis, we validate the technique, show a correlation between level of expression and biological importance, define the complement of invariant genes and analyze absolute levels of expression by functional class to develop ways of understanding an organism's biology without comparison to another growth condition. 相似文献