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261.
A cDNA clone (Bc329) encoding calmodulin was isolated from a Bryonia cDNA library by screening with cloned Arabidopsis calmodulin cDNA. The cDNA Bc329 was 899 bp full-length clone. The predicted amino acid sequence consists of 149 residues and reveals a high homology with other known plant calmodulins (91 to 99% identity). Genomic southern blot suggests that Bryonia calmodulin is encoded by a single-copy gene. The Bc329 clone was used as a probe to study the expression of calmodulin mRNA after a mechanical stimulus applied on young Bryonia internodes. The steady-state of calmodulin mRNA reached a maximum 30 min after the treatment before it progressively decreased. The role of calcium and calmodulin as second messengers is discussed with regard to environmental changes. 相似文献
262.
A genetic control of humoral immune response in pigs against hen egg-white lysozyme was shown to be linked to the major histocompatibility complexSLA. This control was detected when high antigen doses were used for immunization. It was more prominent with small immunizing doses of lysozyme. Under these latter conditions,SL- A heterozygous individuals exhibited a higher response than correspondingSL- A homozygous animals, suggesting a complementation phenomenon between several genes, at least one of which is linked to the porcine MHC,SL- A. 相似文献
263.
Mohamed A. Abdallah Jean-Jacques Andre Jean-François Biellmann 《Bioorganic chemistry》1977,6(2):157-163
The preparation of a spin-labelled analogue of nicotinamide adenine dinucleotide, 3-(4′,4′,5′,5′-tetramethyl-3′-oxide-1′-oxyl-2′-imidazolinyl) pyridine adenine dinucleotide, is descrebed. This compound was obtained by treatment of 3-carboxaldehyde pyridine adenine dinucleotide with 2,3-dimethyl-2,3-dihydroxylaminobutane followed by oxidation with lead dioxide. The interpretation of the particular electron spin resonance spectra of this nitronylnitroxide (five lines) in terms of the rotational correlation time of the radical is shown to be possible. The high stability of this compound makes its use in NAD+-dependent biological systems feasible. 相似文献
264.
Ali Tekitek MmeJosette Berreur-Bonnenfant Jean-Pierre Ferezou Jean-Jacques Meusy Michel Barbier Edgar Lederer 《Biochimie》1977,58(11-12)
Extracts from muscles, testis, seminal vesicles and ovaries of the Crab, Carcinus maenas, have been studied in vitro, in presence of [14C]-methyl S-adenosylmethionine, with an E. coli tRNA as methyl acceptor. The highest level of methylases is found in the testis. It has been reported previously that a purified fraction extracted from the androgenic glands of Carcinus maenas inhibits the vitellogenesis in ovaries. We now show that the same fraction inhibits tRNA methylation in an extract of testis as methylase; a 50 per cent inhibition is obtained with about 10 μg of a purified fraction corresponding to 15 glands. With an enzymatic preparation from the ovaries, a 50 per cent inhibition of the tRNA methylase is observed with the purified extract from 4 glands. 相似文献
265.
Gérard Cros Jean-Pierre Gies Dominique Cahard Pascale Cohen Barbara Filipek Jean-Jacques Mongold Jean-Jacques Serrano 《Molecular and cellular biochemistry》1992,109(2):181-183
Evolution of cholinergic response of rat isolated trachea was determined after various durations of diabetes (17, 40, 90, 150 and 210 days). Long-term diabetes was associated with both impairment of contractility and supersensitivity to cholinergic stimulation. However, the mechanism of these alterations remains to be determined, as response to field stimulation was not specifically altered while electron microscopy studies could not detect any significant change in the aspect of nerves, smooth muscle or epithelium. As well, binding studies of lung cholinergic receptors using the antagonist ligand [3H]-quinuclidinyl benzylate and the agonist carbachol did not detect any change in diabetic animals. 相似文献
266.
267.
Jean-Jacques Lareyre Marie-Genevive Matti Susan Kasper David E. Ong Robert J. Matusik Marie-Claire Orgebin-Crist 《Molecular reproduction and development》1998,50(4):387-395
The murine epididymal retinoic acid-binding protein (mE-RABP) is specifically synthesized in the mouse mid/distal caput epididymidis and secreted in the lumen. In this report, we have demonstrated by Southern blot analysis of genomic DNA that mE-RABP is encoded by a single-copy gene. A mouse 129/SvJ genomic bacterial artificial chromosome (BAC) library was screened using a cDNA encoding the minor form of mE-RABP. One positive BAC clone was characterized and sequenced to determine the nucleotide sequence of the entire mE-RABP gene. The molecular cloning of the mE-RABP gene completes the characterization of the 20.5-kDa–predicted preprotein leading to the minor and major forms of mE-RABP. Comparison of the DNA sequence of the promoter and coding regions with that of the rat epididymal secretory protein I (ESP I) gene showed that the mE-RABP gene is the orthologue of the ESP I gene that encodes a rat epididymal retinoic acid-binding protein. Several regulatory elements, including a putative androgen receptor binding site, “CACCC-boxes,” NF-1, Oct-1, and SP-1 recognition sites, are conserved in the proximal promoter. Analysis of the nucleotide sequence of the mE-RABP gene revealed the presence of seven exons and showed that the genomic organization is highly related to other genes encoding lipocalins. The mE-RABP gene was mapped by fluorescent in situ hybridization to the [A3-B] region of the murine chromosome 2. Our data, combined with that of others, suggest that the proximal segment of the mouse chromosome 2 may be a rich region for genes encoding lipocalins with a genomic organization highly related to the mE-RABP gene. Mol. Reprod. Dev. 50:387–395, 1998. © 1998 Wiley-Liss, Inc. 相似文献
268.
Roger Mawa Dominique Mis Marie Claude Gagnieu Denis Grancher Michelle Petit-Ramel Françoise Bressolle Jean-Jacques Vallon 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,677(2):331-338
This paper describes a highly specific and sensitive method for quantifying oxazepam and its diastereoisometric glucuronides in serum. The method involves sample clean-up by solid-phase extraction on C18 cartridge followed by quantitation on a reversed-phase HPLC column. Diazepam is used as internal standard. Extraction recovery from serum proved to be more than 86%. Precision, expressed as C.V., was in the range 1.2–9.5%. The limits of quantification were 40, 400, and 200 nmol/l for oxazepam, S-(+)- and R-(−)-glucuronides, respectively. This method was applied to the determination of oxazepam and its diastereoisometric glucuronides in serum collected during a pharmacokinetic study performed in sheep after oral administration of racemic oxazepam. S-(+)/R-(−) ratios were measured all along the sampling time collection and the pharmacokinetic parameters were determined. 相似文献
269.
Anne W. Rimoin Vivian Helena Alfonso Nicole A. Hoff Reena H. Doshi Prime Mulembakani Nevile K. Kisalu Jean-Jacques Muyembe Emile W. Okitolonda Linda L. Wright 《EcoHealth》2017,14(3):552-563
Due to the high level of biological diversity in the Congo Basin and human population dependence on bushmeat, the DRC represents an ideal location for expanding knowledge on wild animal exposures and thus the potential for transmission of zoonotic pathogens. However, limited information exists on patterns and extent of contact with wildlife in such communities. Using a cross-sectional study, 14 villages in the Sankuru Province of the DRC were surveyed between August and September 2007. Villagers ≥ 1 year of age and at home of the time of the survey were eligible and enrolled to describe and assess factors associated with animal exposures (both activity and type of animal). Among respondents, 91% reported exposure to rodents, 89% to duikers, 78% to non-human primates (NHPs), and 32% reported contact with bats in the month prior to the survey. The most frequently reported activities included eating (95%), cooking (70%), and butchering or skinning of animals (55%). The activities and animals to which subjects had contact varied by sex and age. Moreover, we observed a high correlation of the same activities across animal types. In this and other populations that rely on bushmeat, there is a high frequency of exposure to multiple animal species through various modalities. In the event of future zoonotic disease outbreaks, effective public health interventions and campaigns that mitigate the risk of animal contact during outbreaks need to be broad to include various modes of contact and should be directed to both men and women across all age groups. As available information is limited, further studies are necessary to better understand the complex relationships and exposures individuals have with animals. 相似文献
270.