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1.
The 7S NGF complex from the male mouse submaxillary gland consists of the , and subunits in the ratio 22. The (NGF) subunit contains all the known biolocial activity of 7S NGF. The and subunits are both members of glandular kallikrein gene family, yet only subunit has protease activity. The subunit plays a role in the processing of preproNGF to its mature form, while the role of the subunit is not yet understood. Despite the fact that 7S NGF has been extensively characterized, no other NGF complex has been characterized, nor have the or subunits been observed in tissues which express NGF. We have therefore purified and characterized the NGF complex from the submaxillary glands of the ratMastomys natalensis in order to more fully understand the roles of the and subunits. The NGF complex from M. natalensis contains subunits similar to those found in mouse 7S NGF. Although similar, there are significant differences between mouse and M. natalensis NGF complexes, especially in the degree of post-translational modification of the and NGF subunits, the expression of esterase activity and the ease with which the complexes dissociate. Evidence is presented that suggests that the NGF complex from M. natalensis may consist of subunits in the ratio 2. The amino acid sequence of the M. natalensis NGF suggests some, but not all, ways in which these differences arise.Special issue dedicated to Dr. Lawrence Austin  相似文献   

2.
Summary Theoretical studies on the necessary number of components in mixtures (for example multiclonal varieties or mixtures of lines) have been performed according to yielding ability. All theoretical investigations are based upon a Gram-Charlier frequency distribution of the component means with skewness 1 and kurtosis 2. The selected fraction p of the best components constitutes the mixture under consideration. The same selection differential S = S (p, 1, 2) can be realized by different parameter values of p, 1 and 2. Therefore, equal yield levels of the mixture can be achieved by different selected fractions p which implies different numbers of components in the mixture. Numerical results of S = S(p) for different values of 1 and 2 are presented and discussed. Of particular interest are the selected fractions p which lead to a maximal selection differential S. These results on S for large populations must be reduced in the case of finite population size. For this correction term we used an approximation B = B (p, n, 1, 2) given by Burrows (1972) where n = number of selected components. For given parameter values of 1, 2 and p, the necessary number n of components can be calculated by using the condition: Burrows-correction less than a certain percentage g of S — for example with g = 0.05 or g = 0.01. For given 1 and 2, the number n leading to a maximal selection differential S can be regarded as necessary number of components (necessary = maximum gain of selection under the given conditions). Numerical results are given for 2 = 0 and for eight situations which are defined by linear relations 2 = c 1 between skewness and kurtosis. These cases will contain all possible numerical situations for 1 and 2, which may be relevant for practical applications. The necessary number of components turns out to be nearly independent of the numerical value of the kurtosis 2. The n-intervals leading to selected fractions p from 0.01 to 0.20 approximately are: 2 n 4 for g = 0.05, 6 n 20 for g = 0.01 and 11 n 40 for g = 0.005, respectively. However, percentages g less than 0.01 would be unrealistically excessive. Therefore, following the assumptions and restrictions given in this paper one may conclude that n = 20 seems to be an appropriate upper bound for the necessary number of components in mixtures.  相似文献   

3.
Summary In this first article on the carotenoids of Myxobacterales we report on the minor carotenoids of Stigmatella aurantiaca: phytoene, phytofluene, lycopene, -carotene, 4-keto--carotene, 1,2-dihydro-1-hydroxy--carotene, 4-keto-1,2-dihydro-1-hydroxy--carotene, 4-keto-1,2-dihydro-1-hydroxy-torulene, and 1,2,1,2-tetrahydro-1,1-dihydroxy-lycopene. These pigments account for about 10% of total carotenoids.  相似文献   

4.
Summary Changes in the -butyrolactone and pantolactone contents in yeast cells and musts during fermentation and subsequent flor veil formation of Sherry wines were studied. Saccharomyces cerevisiae race cerevisiae, S. cerevisiae race bayanus and S. cerevisiae race capensis were used. During the alcoholic fermentation (first 31 days), -butyrolactone contents in musts and yeast cells were similar for the three yeast races tested. In this period, pantolactone was excreted to the must by bayanus and capensis races, and it was not detected in cerevisiae race cells. During flor veil formation (31 to 134 days), bayanus and capensis races yield higher -butyrolactone and pantolactone contents than cerevisiae race in the wines. In the final wines, pantolactone contents were always lower than those of -butyrolactone.  相似文献   

5.
Adoptive immunotherapy using MHC-nonrestricted-lymphocytes, peripheral blood T cells and NK cells was devised. Peripheral blood mononuclear cells (3 x 107) were selected by immobilization to anti-CD3 monoclonal antibody for 4 days and cultured for 2 weeks in the presence of IL-2. Thereafter they were reactivated by 500 U/ml of IFN- and 1000 U/ml of IL-2 for 1 hour. Enhancement of NK and LAK activities was confirmed. Peripheral blood T cells proliferated in response to immobilized anti-CD3 antibody (3% to 30%). Approximately 6 x 109 BRM-activated killer (BAK) cells composed of CD56+ T cells and CD56+ NK cells, were dispensed to cancer patients via intravenous drip infusion. Nine patients were treated with BAK cells every 2 weeks or every month on an outpatient basis. During the course of adoptive immunotherapy, the crossed affinity immunoelectrophoresis (CAIE) pattern of serum immunosuppressive acidic protein (IAP) was analysed. Both the production and glycosylation pattern of IAP is changed in response to tumor enlargement and may therefore act as a marker of the disease progression. During the course of BAK therapy, the glycosylation IAP pattern of 6 patients changed from tumor (T) to normal (N). In addition, the performance status of all patients was maintained at 90–100% of the Karnofsky scale and any side effects including fever were not observed during treatments with BAK cells. Moreover, the overall quality of life (QOL) of the patients, scored at the Face scale was favorable. In addition, blood levels of activated T cells producing IFN- were assayed as an indication marker of BAK therapy. The normal range of IFN- producing T cells comprised 6.9 ± 0.9% of peripheral blood mononuclear cells (PBMC), according to a single cell FACScan analyses of PBMCs derived from normal individuals. IFN- producing T cells of Patients No. 8 and 9, who received extensive chemotherapy before initiation of BAK therapy, comprised only 0.2% and 2% of PBMC, respectively. These patients died 3 and 6 months after beginning BAK therapy. Peripheral blood T cells of Patients Nos. 1–7 proliferated in response to immobilized anti-CD3 antibody and the frequency of IFN- producing T cells in PBMC preparation of these patients were over 3% before initiation of BAK therapy. Since our data show a positive correlation between survival time and initial T cell counts, a low frequency of these cells may contraindicate BAK therapy.  相似文献   

6.
We have isolated an unusual T cell receptor chain cDNA clone (7.1) from a library made from RNA derived from adult thymus of C57BL/Ka mice. This cDNA clone corresponds to the appropriately processed C1 constant region exons preceded by 1.5 kb of J-C1 intron. The 7.1 coding region is extremely homologous to the C1 gene of BALB/c mice, differing at the protein level by a single deletion (alanine 139) and a single substitution. This latter change eliminates the sole N-linked sugar attachment site, providing a basis for strain-specific glycosylation patterns. The J-C1 intronic region contains two DNA segments (termed J1 and J2) that are highly reminiscent of joining (J) segments; both have potentially functional recombination and donor splice sequences flanking an open reading frame. Northern analysis suggests that 7.1 may be derived from a large, variable region-containing precursor.  相似文献   

7.
A catalytic fragment, 1-298, derived from limited chymotryptic digestion of phosphorylaseb kinase (Harris, W.R.et al., J. Biol. Chem., 265: 11740–11745, 1990), is reported to have about six-fold greater specific activity than does the subunit-calmodulin complex. To test whether there is an inhibitory domain located outside the catalytic core of the subunit, full-length wild-type and seven truncated forms of were expressed inE. coli. Recombinant proteins accumulate in the inclusion bodies and can be isolated, solubilized, renatured, and purified further by ammonium sulfate precipitation and Q-Sepharose column. Four out of seven truncated mutants show similar ( 1-353 and 1-341) or less ( 1-331 and 1-276) specific activity than does the full-length wild-type , 1-386. Three truncated forms, 1-316, 1-300, and 1-290 have molar specific activities approximately twice as great as those of the full-length wild-type and the nonactivated holoenzyme. All recombinant s exhibit similarK m values for both substrates, i.e., about 18M for phosphorylaseb and about 75 M for MgATP. Three truncated s, 1-316, 1-300, and 1-290, have a 1.9- to 2.5-fold greater catalytic efficiency (V max/K m) than that of the full-length wild-type and a 3.5- to 4.5-fold greater efficiency than that of the truncated 1-331. This evidence suggests that there is at least one inhibitory domain in the C-terminal region of , which is located at 301-331· 1-290, but not 1-276, which contains the highly conserved kinase domain, is the minimum sequence required for the subunit to exhibit phosphotransferase activity. Both 1-290 and 1-300 have several properties similar to full-length wild-type , including metal ion responses (activation by free Mg2+ and inhibition by free Mn2+) pH dependency, and substrate specificities.  相似文献   

8.
Escherichia coli ATP synthase has eight subunits and functions through transmission of conformational changes between subunits. Defective mutation at Gly-149 was suppressed by the second mutations at the outer surface of the subunit, indicating that the defect by the first mutation was suppressed by the second mutation through long range conformation transmission. Extensive mutant/pseudorevertant studies revealed that / and / subunits interactions are important for the energy coupling between catalysis and H+ translocation. In addition, long range interaction between amino and carboxyl terminal regions of the subunit has a critical role(s) for energy coupling. These results suggest that the dynamic conformation change and its transmission are essential for ATP synthase.  相似文献   

9.
Summary The immunogold technique, employing antisera with clear-cut specificities, was used to localise different processing stages of pro-opiomelanocortin (POMC) in rabbit melanotropic cells. While the antiserum against 3-MSH labelled all the secretory granules including intrasaccular condensations in the Golgi apparatus, antisera against -MSH only labelled extra-Golgi secretory vesicles (SV). All extra-Golgi SV were likewise labelled with the three antisera against -MSH used, despite their different specificities for the desacetylated, N-acetylated or C-amidated forms of the peptide. The antibody against -endorphin also labelled the extra-Golgi SV, while only some SV were labelled with the antibody against -endorphin. These results correlate with biochemical data in favour of mainly — if not exclusively — intragranular processing of POMC. Except for 3-MSH, the cleavage of which could coincide with Golgi packaging of secretory material, other post-translational modifications of the precursor seem to occur when SV are discharged outside the Golgi area. The cleavage of -endorphin appears to be a later step in POMC processing, occurring in some mature SV.  相似文献   

10.
Robin  Jean H. 《Hydrobiologia》1995,300(1):185-190
The effect of various diets containing linoleic and/or -linolenic acids was studied on n-6 fatty acid composition of the rotifer Brachionus plicatilis. The rotifer's abilities for transformations of n-6 fatty acids were evaluated. Diets containing only linolenic acid as n-6 fatty acid induced low levels of other n-6 fatty acids in rotifers while a diet containing also -linolenic acid led to substantial amounts of di homo -linolenic acid in the rotifers through elongation. Desaturation of -linoleic acid to gamma linolenic appears to be the limiting factor of n-6 highly unsaturated fatty acid biosynthesis by the rotifer. Two sets of experiments were compared using different techniques and different sources of -linolenic acid: Spirulina in inert food or borage oil in emulsion with baker's yeast. Rotifers fed with inert diet with Spirulina contained arachidonic acid while those fed with borage oil had very low arachidonic content. High level of n-3 fatty acids incorporated into the diets seemed to exert inhibitory effects on n-6 transformation rate.  相似文献   

11.
Summary RFLPs of TCR and genes have been analyzed in chronic HBV carriers of three different ethnic populations to determine if there is an association of TCR allotypes with the development of chronic hepatitis B. The RFLPs of TCR and genes were defined respectively by BglII and PvuII genomic fragments on Southern blots. These methods allow allotype assignment. The distribution of TCR alleles showed ethnic variation, with one allele significantly decreased in Australian Aborigines, but there was no association with chronic hepatitits B. The distribution of TCR alleles did not show ethnic variation. However, a significant frequency decrease of one allele occurred in Aboriginal HBV carriers, suggesting the possibility of involvement of TCR allotypes in the development of the chronic HBV carrier state in Australian Aborigines.  相似文献   

12.
Summary Five monoclonal antibodies raised against an enriched C hordein fraction have been characterized in detail and were found to be specific for the members of the sulphur-rich hordein family. Two antibodies specific for B hordein polypeptides were identified, one of which reacted predominantly with CNBr cleavage class III polypeptides. 1 hordein was recognized by two antibodies, of which one also reacted with 2 hordein and several members of the CNBr cleavage class II B hordein polypeptides. One antibody recognized 3 hordein but cross-reacted at higher antibody concentration with almost all of the B and C hordein polypeptides. The specificity of the monoclonal antibodies was confirmed by Western blotting of one- or two-dimensionally separated hordein from the B hordein-deficient mutant hor2ca and its wild-type Carlsberg II and the 3 hordein-deficient genotype Nevsky. The identification of the hordein-specific monoclonal antibodies was further supported by immune precipitation of in-vitro transcribed and translated 2 hordein, and hor2ca and Carlsberg II mRNA translation products. The monoclonal antibodies were used to screen for mutants in hordein synthesis. Two mutants, one deficient in 1 hordein synthesis and a second in 2 or closely related B hordein polypeptides were identified. A model is proposed for the evolution of the sulphur-rich hordein loci Hor5 and Hor2.  相似文献   

13.
Summary The expression of the monocyte membrane glycoprotein CD14 was measured and related to the serum interferon (IFN) concentration in thirteen patients with disseminated cancer during treatment with human recombinant interferon (rIFN). The drug was administered by continuous subcutaneous infusion using an escalating dose schedule, starting at 50 µg/day or 100 µg/day and increasing weekly up to 600 µg/day, if tolerated. Treatment was continued at a mean maximal tolerated dose of 200 µg/day for a median duration of 43 days. Serum IFN concentration and monocyte CD14 antigen expression (immunofluorescence with the monoclonal antibody LeuM3 and fluorescence-activated cell sorting analysis) were determined weekly. The serum IFN concentration was positively correlated with the rIFN dose (P <0.05). Therapy induced a dose-dependant enhancement of CD14 antigen expression. The increase in mean CD14 fluorescence intensity was on average 60% after 3 weeks of treatment at a mean dose of 220 µg rIFN/day and was reversed after withdrawal of therapy. Patients with a rapidly rising serum IFN concentration (starting dose 100 µg/day) showed a smaller increment in CD14 fluorescence intensity than those with slowly rising serum IFN levels (starting dose 50 µg/day). Since rIFN is known to down-regulate CD14 antigen expression in vitro, monocytes from patients off therapy and from healthy volunteers were cultured with this cytokine. A similar decrease of CD14 fluorescence was observed in both groups. In patients several factors, such as IFN concentration, duration of drug effect and type of serum, were evaluated and could not explain the discrepant in vivo and in vitro findings. In conclusion, the monocyte marker CD14 was found to be differentially regulated by rIFN in vivo and in vitro. In vivo, secondary mediators, induced by rIFN and acting on a constantly renewed cell population, may contribute to the enhanced CD14 expression.  相似文献   

14.
The influence of interferon alpha and gamma alone or in combination on the augmentation of human natural cytotoxicity was studied. Treatment of peripheral blood lymphocytes with IFN- led to a rapid augmentation of NK activity, in contrast to IFN- where target cell killing was observed only following 18 hrs exposure of lymphocytes to IFN-. The results of the single cell assay paralleled those obtained using the Chromium release test, but neither interferon type caused an increase in the number of target binding lymphocytes. The combined effect of IFN- and IFN- in stimulating human natural cytotoxicity demonstrated individual lymphocyte responses to be variable. Exposure of lymphocytes to IFN- and IFN- for 18 hrs prior to assay for cytotoxicity usually decreased the level of cytotoxicity compared with control values, whereas other treatment regimes gave an additive and sometimes synergistic effect. Only treatment with IFN- for 18 hrs and IFN- for one hr produced a synergistic response in the majority of individuals tested. We conclude from this study that individual responses to IFN- and IFN- alone or in combination are variable and dependent upon timing of exposure of lymphocytes to individual interferon types, and possibly reflects the donor status at the time of sampling.  相似文献   

15.
The methanolysis products of polyhydroxyalkanoic acids (PHAs) containing 4-hydroxybutyric acid (4HB), 4-hydroxyvaleric acid (4HV), and 4-hydroxyhexanoic acid (4HHx), when analyzed by GC-MS, showed two major chromatographic peaks with characteristic retention times of each methyl ester of 4-hydroxyalkanoic acid and the corresponding g-lactone (-butyrolactone, -valerolactone, -caprolactone, respectively). The method and results of GC-MS could be incorporated into an efficient screening procedure for isolation of bacterial strains which could accumulate a PHA containing 4-hydroxyalkanoic acid as the principal monomer from structurally related carbon substrates.  相似文献   

16.
Summary Few clinical responses have occurred in preliminary studies using the cytokines tumor necrosis factor (TNF) or interferon (IFN) in cancer patients. This may be related to the observation that many malignant cell lines are resistant to lysis by these cytokinesin vitro. Resistance to lysis by TNF or IFN in many cells is controlled by a protein-synthesis-dependent mechanism, such that when protein synthesis is inhibited cells become sensitive to lysis by these cytokines. Because there is some evidence that TNF and IFN act through different lytic mechanisms and are opposed by different resistance mechanisms, we treated a panel of eight cell lines, five derived from human cervical carcinomas (ME-180, MS751, SiHa, HT-3, and C-33A) and three derived from ovarian carcinomas (Caov-3, SK-OV-3, and NIH: OVCAR-3) with both TNF and IFN to determine whether such combination treatment might maximizein vitro cell lysis. Our results showed that pretreatment with IFN followed by exposure to TNF in the presence of protein synthesis inhibitors increased lysis of seven of the eight cell lines above that seen with either TNF or IFN and inhibitors of protein synthesis. Only the cell line C-33A was resistant to lysis by TNF and IFN, when exposed to these agents both alone and in combination with protein synthesis inhibitors. Clinically, combining the cytokines TNF and IFN with protein synthesis inhibitors may maximize thein vivo lytic effects of these cytokines.Supported by American Cancer Society Career Development Award 90-221  相似文献   

17.
Type-1-protein phosphatase (PP-1) activity is reduced in skeletal muscle from human subjects with insulin resistance (Kida et al. 1990). This reduced phosphatase activity probably leads to the abnormal insulin action for glucose storage observed in insulin-resistant subjects. In the present study, a human homolog of rat liver PP-11 cDNA was isolated from human skeletal muscle. The nucleotide sequence contains a 957-nucleotide open reading frame encoding an amino acid sequence identical to that encoded by rat liver PP-11 cDNA. Northern blot analysis shows PP-11-specific mRNA is expressed in human heart, brain, placenta, lung, liver, skeletal muscle, kidney, and pancreas. PP-11 was localized to human Chromosome 12.  相似文献   

18.
Summary Rye secalins are a polymorphic mixture of polypeptides which are classified into four major groups. Previous studies have shown that the structural genes for two of the groups (the -secalins and 40K -secalins) are located on the short arm of chromosome 1R and those for a third group (the high molecular weight secalins) on the long arm of the same chromosome. Analysis of F2 grain from crosses between inbred lines of S. cereale shows that the structural genes for the -secalins (designated Sec 1) and the high molecular weight secalins (designated Sec 3) are loosely linked (40.8 ±3.76% recombination, 57.4 ± 11.30 cM). Analysis of wheat rye addition lines shows that the structural genes for the 75K -secalins are present on chromosome 2R. This locus is provisionally designated Sec 2. These genes are probably derived from those for the 40K -secalins by duplication, divergence and translocation. Analysis of secalin fractions from wild species of rye shows that all contain 75K -secalins, indicating that the duplication and divergence, if not the translocation, occurred before speciation of the genus.  相似文献   

19.
-Hydroxybutyrate uptake by rat brain striatal slices was studied. The uptake was saturable with aK m of 702±107.10–6M. -Hydroxybutyrate uptake was sodium dependent and inhibited by the omission of potassium. In addition, the effect of ouabain suggests that the transport is dependent on a cation gradient. Several analogues of -hydroxybutyrate inhibit the transport system. GABA has no significant effect. This energy and cation dependent transport system is in favor of a transmitter or modulator role of -hydroxybutyrate in the rat brain striatum.  相似文献   

20.
180 rainbow trouts (Salmo gairdneriRich.), aged from 1 to 3 years, were examined for fluctuations, caused by age and season, by means of colour index (CI), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC).CI and MCH behave similarly. Both are increasing until the 2nd year and stay relatively constant thereafter. If the gender is not considered — there are no significant differences in the values of males and females — the CI increases from 1,4 in the first year over 1,6 to 1,7 in the age of 3 years, and the MCH increases from 44,4 over 52,6 , 56,8 , 58,1 to 55,5 .A seasonal periodicity of both indices could not be indicated on not-matured animals (F2) which were two summers of age. Only, the january values appeared increased — CI: 2, MCH: 68,3 — otherwise the CI varies between 1,8 and 1,7 and the MCH between 53,3 and 59,1 .The MCHC-values of the age groups examined vary between 24,4% and 27,3%. The values of the yearlings form an exception (19,8%). These values certainly are inexact and too low because of the small number of individuals checked (3).

Mit finanzieller Unterstützung durch die DFG.Institut für Siedlungswasserbau und Wassergütewirtschaft der Universitat Stuttgart Fischtoxikologische Arbeitsgruppe  相似文献   

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