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101.
Manuel P. Mark William T. Butler Charles W. Prince Richard D. Finkelman Jean-Victor Ruch 《Differentiation; research in biological diversity》1988,37(2):123-136
New aspects of the distribution and developmental appearance of the 44-kDa bone phosphoprotein (44K BPP, also called sialoprotein I or osteopontin) and bone gamma-carboxyglutamic acid (Gla)-containing protein (BGP, also called osteocalcin) during osteogenesis and dentinogenesis were investigated with immunocytochemical techniques using monospecific, affinity-purified polyclonal antibodies. Sections from newborn rat incisors and from various bone anlagen of newborn animals and fetuses were processed for detection of 44K BPP or BGP antigenicity. In addition, histochemical reactions for detection of alkaline phosphatase or calcium salts were performed on a number of the sections. The 44K BPP appears to be synthesized and secreted by chondrocytes only in the areas of cartilage-to-bone transition; these cells could participate indirectly in the process of bone formation by providing a suitable scaffold onto which primary marrow osteoblasts attach and spread. During osteogenesis, 44K BPP is found in bone-forming cells almost concomitantly with the appearance of alkaline phosphatase and before osteoid deposition, whereas BGP is still absent during early stages of mineralization. We hypothesize that this dramatic difference between the developmental appearance of 44K BPP and BGP reflects the delayed expression of the BGP gene relative to that of 44K BPP. In long-term cultures of bone marrow from adult mice, some fibroblastic cells expressed the 44K BPP phenotype; these cells could represent early osteogenic progenitor cells. Some experiments also suggested that, as with BGP, 44K BPP or an immunologically related protein is synthesized by some odontoblasts and secreted into predentin, prior to the onset of mineralization. 相似文献
102.
103.
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. |
104.
Leta O. Helsel William F. Bibb Charles A. Butler Paul S. Hoffman Roger M. Mckinney 《Current microbiology》1988,16(4):201-208
A monoclonal antibody was produced against a cytoplasmic membrane protein that appears to be common to all species of the genusLegionella. The antibody was positive in polyacrylamide gel electrophoresis and Western blotting with extracts of all of 22 species type strains ofLegionella that were tested. The apparent molecular mass of the protein varied from 57.2 to 62.1 kilodaltons for the 23 species type strains ofLegionella. An enzyme-linked immunosorbent assay (ELISA) was developed with the monoclonal antibody to enable rapid screening of clinical and environmental isolates forLegionella. All of 23 species type strains ofLegionella that were tested were strongly positive with the monoclonal antibody in the ELISA. Among 27 other bacterial species and 84 strains that were tested, onlyBordetella ssp. andAcinetobacter lwoffii were cross-reactive in the ELISA. These two cross-reactive species are readily distinguishable fromLegionella by culture characteristics. The monoclonal antibody may also be useful in tests to detect the genus-wide antigen in body fluids of patients with legionellosis. 相似文献
105.
Charles E. Stager Dr. James R. Davis Mario N. Saccomani Corpus O. Ortigoza Reuben D. Wende James W. Raleigh 《Current microbiology》1988,17(5):243-247
Two-hundred and fifteen isolates ofMycobacterium tuberculosis were evaluated with the BACTEC 460 radiometric method for susceptibility to isoniazid, rifampin, ethambutol, and streptomycin (SM); a revised protocol for inoculum preparation was used. Fresh clinical isolates were subcultured into 7H9 broth and then photometrically adjusted to the equivalent of a 0.5 McFarland standard, one-half the recommended inoculum density. This method produced an overall 98.3% correlation with a conventional agar method. The sensitivity of this procedure was good for all drugs tested except for the lowest concentration of SM (2 g/ml). Specificity was excellent for all drugs tested. After repeat testing, only four discrepancies were found, yielding a 99.8% correlation between the two systems. The time required for susceptibility tests averaged 4.6 days. This method for inoculum preparation effectively minimized the number of susceptibility tests exceeding the threshold value before the fourth day of incubation. This allowed for definite trends of the growth index values to become established before interpretation of results. 相似文献
106.
Attempt to detect recombination between B-F and B-L genes within the chicken B complex by serological typing,in vitro MLR,and RFLP analyses 总被引:1,自引:1,他引:0
Karel Hála Anne-Marie Chaussé Yves Bourlet Olli Lassila Viktor Hasler Charles Auffray 《Immunogenetics》1988,28(6):433-438
In search for recombinants within the chicken major histocompatibility B complex, 1155 animals from crosses between the congenic lines CB (B12) and CC (B4) were tested with alloantibodies and monoclonal antibodies for the B-F (class I), B-L (class II), and B-G (class IV) antigens and by mixed lymphocyte reaction. The absence of detectable recombination was confirmed by restriction fragment length polymorphism analysis with B-L
and B-F probes. Together with previous reports, this indicates that the distance between the B-F and B-L loci is below 0.01 centimorgan. 相似文献
107.
Summary With the -amylase promoter and ribosome binding site,Bacillis subtilis was used to express the sweet plant protein thaumatin II cDNA fused in the correct reading frame to the -amylase leader peptide. The r-thaumatin was purified from the medium on a S-Sepharose column and detected with western blots by sheep -thaumatin antibodies. The r-thaumatin and authentic thaumatin were the same size when reduced by 2-ME and the same size when not reduced. 相似文献
108.
Internal waves, primary production and the compensation depth of marine phytoplankton 总被引:2,自引:0,他引:2
Internal waves increase the average light intensity experiencedby phytoplankton and augment the compensation depth below whichno net photosynthesis occurs. These effects may be quite largein eutrophic waters with moderate or high light attenuationcoefficients. Data on internal waves and light attenuation canbe used to correct standard estimates of (new) primary productionin the lower euphotic zone based on uptake rates of carbon ornitrogen isotopes. 相似文献
109.
Servaas Visser Charles J. Slangen Fred A. Exterkate Gerrie J. C. M. de Veer 《Applied microbiology and biotechnology》1988,29(1):61-66
Summary The specificity of a cell wall proteinase (PI) from Streptococcus cremoris strain HP in its action on bovine -casein was determined. To this end an enzymic digest (pH 6.2; 15° C) of -casein was brought to pH 4.6 and the soluble fraction separated by semi-preparative reversed-phase HPLC. Purified peptides were analyzed by amino acid and end-group analysis. Ten chromatographic components were identified, which together accounted for at least seven cleavage sites all being located in the C-terminal fifty-residue part of -casein. In five cases it concerned a Gln-X or X-Gln peptide linkage. The specificity of this proteinase from S. cremoris HP shows similarity to that reported for a cell wall proteinase from S. lactis NCDO 763 in its action on -casein.Presented at the second FEMS Symposium on Lactic Acid Bacteria held in 1987 at Wageningen, Netherlands 相似文献
110.
Calf brain 3'-phosphoadenosine 5'-phosphosulfate (PAPS):proteoheparan sulfate (PHS) N-sulfotransferase activity is solubilized by extracting salt-washed microsomes with 1% Cutscum. A protocol is described for the partial purification of the sulfotransferase activity utilizing: (1) diethylaminoethyl (DEAE)-Sephacel, (2) heparin-Sepharose CL-6B, and (3) 3',5'-ADP-agarose as chromatographic supports. Sulfotransferase activity was followed by using 3'-phosphoadenosine 5'-phospho[35S]sulfate and endogenous acceptors in heat-inactivated microsomes as exogenous substrates. Two chromatographically distinct fractions (ST1 and ST2) of sulfotransferase activity are resolved on DEAE-Sephacel. Both sulfotransferase activities have been partially purified and characterized. An apparent purification of the two N-sulfotransferase fractions of 22- to 29-fold, relative to the microsomal activity, is achieved by this procedure. Since ST1 appears to represent approximately 24% of the total microsomal activity, a purification of 89-fold has been estimated for this fraction. Neither sulfotransferase activity was stimulated by MnCl2, MgCl2, or CaCl2 added at 10 mM, nor inhibited by the presence of 10 mM EDTA. ST1 and ST2 are optimally active at pH 7.5-8. Apparent Km values for PAPS of 2.3 microM and 0.9 microM have been determined for ST1 and ST2, respectively. ST1 exhibits N-sulfotransferase activity primarily and is inhibited by phosphatidylserine whereas the ST2 fraction contains a mixture of N- and O-sulfotransferase activity and is stimulated by phosphatidylserine, phosphatidylcholine, and lysophosphatidylcholine. The detection of two chromatographically distinct sulfotransferase activities raises the possibility that N-sulfation of proteoheparan sulfates could be catalyzed by more than one enzyme, and that N-sulfation and O-sulfation of proteoglycans are catalyzed by separate enzymes in nervous tissue. 相似文献