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121.
John R. Shaffer Jenna C. Carlson Brooklyn O. C. Stanley Eleanor Feingold Margaret Cooper Michael M. Vanyukov Brion S. Maher Rebecca L. Slayton Marcia C. Willing Steven E. Reis Daniel W. McNeil Richard J. Crout Robert J. Weyant Steven M. Levy Alexandre R. Vieira Mary L. Marazita 《Human genetics》2015,134(2):159-167
122.
A method is described for locating the O-(2-hydroxypropyl) groups in O-(2-hydroxypropyl)-substituted guar. Per-O-methylation of the O-(2-hydroxypropyl)guar yielded guar that was partially O-methylated and partially O-(2-methoxypropyl)ated. This polymer was hydrolyzed, to afford a mixture of partially O-methylated monosaccharides and partially O-(2-methoxypropylated), partially O-methylated monosaccharides. These monosaccharide derivatives were reduced, and the alditols acetylated, to give a mixture of partially O-acetylated, partially O-methylated alditols with partially O-acetylated, partially O-(2-methoxypropyl)ated, partially O-methylated alditols. These alditol derivatives were identified by gas-liquid chromatography-mass spectrometry, and quantitated by gas-liquid chromatography. 相似文献
123.
Important protein-based immunoreactivities have long been associated with the cell wall core of mycobacteria. In order to explore the molecular basis of such activities, purified cell walls of Mycobacterium tuberculosis were extracted with sodium dodecyl sulfate to produce an insoluble residue composed of the mycolylarabinogalactan-peptidoglycan complex and about 2% of unextractable protein. Treatment of the product from an avirulent strain of M. tuberculosis with trifluoromethanesulfonic acid released a single polypeptide with a molecular size of 23 kilodaltons, accounting for all of the insoluble cell wall protein. Extensive purification and then analysis of the 23-kilodalton protein demonstrated the absence of diaminopimelic acid, muramic acid, or other peptidoglycan components, pointing to either a novel linkage between protein and peptidoglycan or a noncovalent but tenacious association. The released 23-kilodalton protein showed amino acid homology and other similarities to the outer membrane protein OmpF of Escherichia coli. Although a similar product was released in small quantities from cell walls of the virulent M. tuberculosis Erdman and H37Rv by lysozyme treatment, the cell walls of virulent bacilli were dominated by the presence of poly-alpha-L-glutamine, accounting for as much as 10% of their weight. The poly-alpha-L-glutamine was successfully separated from the cell wall proper, demonstrating again the absence of a covalent association between peptidoglycan and the polymer. The antigenicity of these products is demonstrated, and their roles vis-a-vis analogous polypeptides from other bacteria in immunogenicity, pathogenicity, and bacterial physiology are discussed. 相似文献
124.
125.
H P McNeil D P Frenkel K F Austen D S Friend R L Stevens 《Journal of immunology (Baltimore, Md. : 1950)》1992,149(7):2466-2472
An antibody to mouse mast cell protease-5 (MMCP-5) was obtained by immunizing a rabbit with a 17-residue synthetic peptide corresponding to the unique amino acid sequence at residues 146 to 162 in this serine protease. After affinity purification, anti-MMCP-5(146-162) Ig reacted in SDS-PAGE immunoblots to recombinant MMCP-5 and to the native MMCP-5 protein present in the lysates of mouse serosal mast cells and the MC5 line of Kirsten sarcoma virus-immortalized mouse mast cells. Immunocytochemical staining localized MMCP-5 to the cytoplasmic granules of serosal mast cells and Kirsten sarcoma virus-immortalized mouse mast cells. Because mouse bone marrow-derived mast cells express abundant amounts of MMCP-5 mRNA, anti-MMCP-5(146-162) Ig was used to study the translation and granule accumulation of this protease when progenitor cells differentiate into these immature mouse mast cells. Maximal expression of MMCP-5 mRNA occurred after bone marrow cells had been cultured for 2 wk in IL-3-rich WEHI-3 cell conditioned medium, and MMCP-5 protein was detected in these cells. However, electron-microscopic analysis with gold-labeled antibody revealed that the amount of MMCP-5 in the individual granules of bone marrow-derived mast cells varied. The highest concentration of MMCP-5 was found in the most electron-dense secretory granules of the cells. These studies demonstrate the ultrastructural localization of the earliest transcribed mouse mast cell chymase, MMCP-5, and its granule accumulation during the differentiation of mouse bone marrow progenitor cells into immature mouse mast cells. 相似文献
126.
G. Macaloney J. W. Hall M. J. Rollins I. Draper K. B. Anderson J. Preston B. G. Thompson B. McNeil 《Bioprocess and biosystems engineering》1997,17(3):157-167
Bioprocess optimisation is often limited by an inability to measure biomass, nutrient and by-product concentrations in a time frame which allows process adjustments. Near-infrared (near-IR) spectroscopy can potentially be used to measure each of these components within 2 minutes of sampling, using an unprocessed whole broth sample. In the present study the use of near-IR spectroscopy for at-line (rapid off-line) monitoring of biomass, glycerol, ammonium, and acetate in a recombinant Escherichia coli fed batch process was investigated. The following robust correlation models were developed for these analytes using multiple least squares linear regression (MLR): [Glycerol],gl?1 =15.957 ? 2219.270* A(λ2274)?1705.041* A(λ2172); [Acetate],gl?1=27.683 ?1757.258* A(λ2254)+296.903* A(λ2340)?21.325* A (λ620); [Ammonium],gl?1=?1310.502?47912.960* A (λ2148)?135149.300* A(λ1782)?27636.200* A (λ830); and [Biomass],gl?1=14.034?3.548* A(λ602/λ1134) ?4286.050* A(λ928). Using these models permitted rapid simultaneous analysis of all four analytes. This improved monitoring capability was used to develop a high cell density recombinant E. coli fed-batch process in which ammonium and acetate accumulation were minimised leading to higher cell densities. By manipulation of the C?:?N ratio in the complex feed, the toxic effects of ammonium accumulation upon the organism were minimised, thereby facilitating the application of a carbon limited feeding strategy. The effect of these C?:?N ratio medium changes, upon the near-IR measurement capability, was investigated. In this process, near-IR spectroscopy has been shown to be a powerful, accurate and precise method for simultaneously measuring several key process variables. Its accuracy, precision and utility for at-line measurement and control are evaluated, particularly in reference to processes where the initial medium composition may vary, leading to changes in the chemical matrix. The potential of near-infra red for online analysis and control is discussed. 相似文献
127.
Observations on 56 specimens of Aratinga pertinax when bringing food to the beak prove that 28 birds were right-handed while the other 28 were left-handed. A biometric analysis reveals a slight departure from bilateral symmetry in hindlimb bones in close relationship with handedness. In the right-handed birds, there is a significant predominance in the length of the right hindlimb as a whole and all right limb segments. The opposite holds true in left-handed parrots (except for the femur). Right-handed birds are in general more highly asymmetrical than left-handed ones. There is a positive correlation between asymmetry of homologous segments of a pair of limbs and the asymmetry of the other segments of the same pair of limbs. The absence of significant negative correlations between bilateral differences of the different segments of a limb indicates that departures from bilateral symmetry tend to affect the limb as a whole, and thus is not in agreement with the rule of compensating variations. 相似文献
128.
Observations of adult Agromyza frontella (Rondani) (Diptera: Agromyzidae) in alfalfa, Medicago sativa L. (cv. Saranac), fields in two regions of Quebec, Canada, demonstrated that males were most abundant on alfalfa plants early in the morning and in the late afternoon/early evening, which coincided with the occurrence of bimodal mating activity. Male abundance and incidence of mating were usually negatively correlated with air temperature, solar insolation and wind speed and positively correlated with relative humidity. The daily pattern of female abundance on alfalfa varied less than that of males. Females fed and oviposited throughout the day, and the frequency of these activities were usually positively correlated with air temperature and solar insolation and negatively correlated with relative humidity. Possible reasons for the sexual dimorphism in the daily activity patterns of this leaf miner, and their significance for individual fitness, are discussed.
Résumé L'observation visuelle des adultes de la mineuse virgule de la luzerne, A. frontella, dans des champs de luzerne de deux regions differentes du Québec, ont démontré que les mâles étaient plus nombreux sur les plantes tôt le matin, vers la find de l'après — midi et tôt en soirée, ce qui a coincidé avec l'occurence bimodale de l'accouplement. L'abondance diurne des femelles variait moins que celle des mâles et les femelles se nourrissaient activement pendant toute la journée. La fréquence de l'alimentation et de la ponte chez les femelles (les mâles n'étant observé que très rarement en train de se nourrir) étaient corrélées positivement à la température ambiante de l'air de méme qu'à l'insolation mais étaient négativement corrélées à l'humidité relative. Contrairement aux femelles, l'abondance des mâles et l'incidence de l'accouplement étaient habituellement corrélées négativement à la température ambiante de l'air, à l'insolation et à la vitesse du vent alors qu'elles étaient positivement corrélées à l'humidité relative. Plusieurs hypothèses pouvant expliquer le dimorphisme sexuelle des activitées diurnes de cette mineuse ainsi que leurs implications quant à la fitness, des individus, sont discutés.相似文献
129.
A large number of patients with acquired immune deficiency syndrome develop disseminated infections due to member serotypes of the Mycobacterium avium complex. Seroagglutination on 181 such isolates followed by enzyme-linked immunosorbent assay and thin layer chromatography of the type-specific glycopeptidolipid (GPL) antigens demonstrated that the majority of serotypes were M. avium serotype 4. The specific GPL of serotype 4 was isolated in both the native, acetylated, and the deacetylated forms and its oligosaccharide hapten released as the oligosaccharide alditol by reductive beta-elimination. A comprehensive structural analytical approach developed for more complex carbohydrates was applied to the oligosaccharide alditol in order to reveal glycosyl and glycosyl-linkage composition, sequence arrangements, ring forms, and enantiomeric and anomeric configurations. The structure of the triglycosyl alditol was established as, 4-O-Me-L-Rhap-(alpha 1----4)-2-O-Me-L-Fucp-(alpha 1----3)-L-Rhap- (alpha 1----2)-6-deoxytalitol, in which the nonreducing-end disaccharide unit is unique to serotype 4. The native GPL antigen is diacetylated, presumably at other than the terminal disaccharide, since the antigenicity of both the acetylated and deacetylated antigens are comparable. The structure of the epitope of the type-specific antigen of serotype 4 will serve as the basis for synthetic antigen probes and the target for the monoclonal antibodies required to trace the origins in the environment of the infectious agent and study the epidemiology of human infections. 相似文献
130.
A number of yeast strains, isolated from sugar cane mills and identified as strains of Kluyveromyces marxianus var. marxianus, were examined for their ability to ferment glucose and cane syrup to ethanol at high temperatures. Several strains were capable of rapid fermentation at temperatures up to 47 degrees C. At 43 degrees C, >6% (wt/vol) ethanol was produced after 12 to 14 h of fermentation, concurrent with retention of high cell viability (>80%). Although the type strain (CBS 712) of K. marxianus var. marxianus produced up to 6% (wt/vol) ethanol at 43 degrees C, cell viability was low, 30 to 50%, and the fermentation time was 24 to 30 h. On the basis of currently available strains, we suggest that it may be possible by genetic engineering to construct yeasts capable of fermenting carbohydrates at temperatures close to 50 degrees C to produce 10 to 15% (wt/vol) ethanol in 12 to 18 h with retention of cell viability. 相似文献