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1.
Matairesinol is one of the lignan compounds found in a variety of plant foodstuffs. We investigated the immunomodulatory effects of (-)-matairesinol in vivo and ex vivo by using mice. Although we found no significant differences in the IgG, IgA and IgM levels in the serum, the IgE level was strongly suppressed by the uptake of (-)-matairesinol in both intact and ovalbumin-immunized mice. The immunoglobulin produced by lymphocytes from the spleen was not activated by the intake of (-)-matairesinol. However, lymphocytes in such gut-associated lymphatic tissues as Peyer's patches and mesenteric lymph nodes were activated by the administration of (-)-matairesinol.  相似文献   

2.
Two-photon-excited fluorescence laser-scanning microscopy (2PLSM) has provided a wealth of information about the spatiotemporal properties of biological processes at the single cell and population level. Because such nonlinear optical methods allow for imaging deep within biological tissue, 2PLSM can be combined with patch-clamp techniques to obtain electrophysiological recordings from specific fluorescently labeled cells in vivo. Here a protocol referred to as two-photon targeted patching (TPTP) describes a method that may be used to record from cells in the intact animal labeled by virtually any type of fluorophore. We target neurons that have been optically and genetically identified using green fluorescent protein (GFP) expressed under the control of a specific promoter. TPTP when combined with genetic approaches therefore permits electrophysiological recordings from specified neurons and their compartments, including dendrites. This technique may be repeated in the same preparation many times over the course of several hours and is equally applicable to non-neuronal cell types.  相似文献   

3.
Biosynthesis of carcinine (beta-alanyl-histamine) in vivo   总被引:1,自引:0,他引:1  
Carcinine was biosynthesized by Carcinus maenas from [14C]beta-alanine, [14C] histidine and [14C] histamine. Since carnosine (beta-alanyl-histidine) could not be detected in crab tissues, biosynthesis of carcinine could only be effected by direct coupling of beta-alanine and histamine resulting from histidine decarboxylation. Biosynthesis of carcinine was weak when [14C]beta-alanine and [14C] histidine were used as precursors. On the contrary when [14C] histamine was used, synthesis was important. Thus carcinine appears to be a product of histamine catabolism. After injecting [14C] histamine, radioactive carcinine was concentrated mainly in the heart and nervous system; nonmetabolized [14C] histamine was recovered mainly in the latter. The nervous system might therefore be the seat of carcinine biosynthesis and thus the site of action of histamine.  相似文献   

4.
The comparison of external and internal, pelvimetry measurement was performed on 79, buffalo heifers, and a high, positive correlation (r=0.90) between the two methods was revealed. The pelvic area of the buffalo heifers increased progressively with the advancing age and with the increase in body weight. The convenience with which external pelvimetry could be performed, the simplicity of the equipment which was used and the accuracy of the method would certainly favor the application of external pelvimetry for routine use.  相似文献   

5.
The influence of a variety of treatments on the mobility and crystallinity of poly(hydroxybutyrate) (PHB) in whole cells and native granules has been proved using 13C-n.m.r. spectroscopy and X-ray powder diffraction, and correlated with the known biological effects of these treatments. It was concluded that at least water is responsible for PHB plasticization in vivo, and that only native mobile PHB is susceptible to depolymerases. Another, probably hydrophobic, component appears to be involved either as plasticizer or nucleation inhibitor. Three states of the granule are identified in addition to the native, biologically-competent state: freeze-drying of whole cells leads to a partially-immobilized amorphous state which can be restored virtually to native mobility by rehydration; extended centrifugation of native granules in aqueous suspension, or treatment with hydrophobic detergents under certain conditions, leads to a crystalline state that is less susceptible to exogenous depolymerase; and heating to 95 degrees C or refrigeration has no detectable effect on mobility but leads to inactivation of the granule, presumably via damage to superficial membrane or protein.  相似文献   

6.
Modification of proteins by mono(ADP-ribosylation) in vivo   总被引:5,自引:0,他引:5  
We have pursued the detection of in vivo modified, ADP-ribosylated proteins containing N-glycosylic linkages to arginine. ADP-ribosylated histone, elongation factor 2, and transducin, containing the different known ADP-ribosylated amino acids (arginine, diphthamide, and cysteine, respectively), were employed as model conjugates to establish conditions for the selective detection of adenosine(5')diphosphoribose (ADP-ribose) residues bound to arginine. We report here the detection and quantification of protein-bound ADP-ribose residues in adult rat liver with linkages characteristic of arginine. These mono(ADP-ribose) residues were present in vivo at a level of 31.8 pmol/mg of protein which is 400-fold higher than polymeric ADP-ribose residues. A minor fraction (23%) of the ADP-ribose residues detected were bound via a second, more labile linkage with chemical properties very similar to those described for carboxylate ester linked ADP-ribose.  相似文献   

7.
Bosslet  K.  Czech  J.  Seemann  G.  Monneret  C.  Hoffmann  D. 《Cell biochemistry and biophysics》1994,24(1-3):51-63
A two component system, consisting of a fusion protein and an appropriate prodrug, suited to perform selective tumor therapy in vivo, is presented. The fusion protein, owing to its humanized carcinoembryonic antigen (CEA)-specific variable region, specifically binds to CEA-expressing tumors and has an enzymatic activity comparable to human β-glucuronidase. The prodrug is a nontoxic glucuronide-spacer-derivative of doxorubicin decomposing to doxorubicin by enzymatic deglucuronidation. In vivo studies in nude mice bearing human CEA-expressing tumor xenografts revealed that 7 d after injection of 20 mg/kg fusion protein, a high specificity ratio (>100:1) was obtained between tumor and plasma. Injection of 250 mg/kg of prodrug at d 7 resulted in tumor therapeutic effects superior to conventional chemotherapy without any detectable toxicity. These superior therapeutic effects that were observed using established human tumor xenografts can be explained by the approx 10-fold higher drug concentrations found in tumors of mice treated with fusion protein and prodrug than in those treated with the maximal tolerable dose of drug alone.  相似文献   

8.
Poly(ADP-ribose) has a branched structure in vivo   总被引:2,自引:0,他引:2  
We have searched for the presence of branching in the chromosomal polymer poly(ADP-ribose) as it occurs in vivo. Treatment of the polymer with phosphodiesterase asnd phosphomonoesterase results in the conversion of internal residues to the nucleoside ribosyladenosine and the conversion of points of branching to diribosyladenosine. We have detected diribosyladenosine in digests of the polymer derived from carcinogen-treated SV40 virus-formed 3T3 cells and in normal rat liver, kidney, and spleen. The frequency of residues involved in branching varied from 0.8 to 1.6 mole % over a 50-fold range of total levels of poly(ADP-ribose). Thus, branching seems to be a general feature of poly(ADP-ribose) as it occurs in vivo.  相似文献   

9.
Vital roentgenocontrast investigation of the pancreatic veins has been performed in 125 selective phlebographies of the portal system performed by means of probing through the skin and hepatic catheterization, as well as by means of blood samples from the pancreatic veins. Standard points of the ostia position of the most constantly revealed veins are demonstrated. Accordance between the veins and the glandular parts they drain is described. This makes it possible to localize with certainty hormonally active neoplasms in the organ.  相似文献   

10.
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12.
Nicotianamine forms complexes with Zn(II) in vivo   总被引:2,自引:0,他引:2  
The non-proteinogenic amino acid nicotianamine (NA) is a major player in plant metal homeostasis. It is known to form complexes with different transition metals in vitro. Available evidence associates NA with translocation of Fe, and possibly other micronutrients, to and between different plant cells and tissues. To date, however, it is still extremely challenging to detect metal-ligand complexes in vivo because tissue disruption immediately changes the chemical environment and thereby the availability of binding partners. In order to overcome this limitation we used various Schizosaccharomyces pombe strains expressing a plant NAS gene to study formation of metal-NA complexes in vivo. Tolerance, accumulation and competition data clearly indicated formation of Zn(ii)-NA but not of Cu(ii)-NA complexes. Zn(ii)-NA was then identified by X-ray absorption spectroscopy (XAS). About half of the cellular Zn was found to be bound by NA in NAS-expressing cells while no NA-like ligands were detected by XAS in control cells not expressing NAS. Given the high conservation of eukaryotic metal homeostasis components, these results strongly suggest the possible existence of Zn(ii)-NA complexes also in planta. Reported observations implicating NA in plant Zn homeostasis would then indeed be attributable to direct interaction of Zn(ii) with NA rather than only indirectly to perturbations in Fe metabolism. Re-evaluation of extended X-ray absorption fine structure (EXAFS) spectra for the Zn hyperaccumulator Thlaspi caerulescens showed that NA is as expected not a major storage ligand for Zn. Instead it is hypothesized to be involved in efficient translocation of Zn to above-ground tissues in hyperaccumulators.  相似文献   

13.
In vivo induced antigen technology (IVIAT)   总被引:3,自引:0,他引:3  
In vivo induced antigen technology (IVIAT) is a technique that identifies pathogen antigens that are immunogenic and expressed in vivo during human infection. IVIAT is complementary to other techniques that identify genes and their products expressed in vivo. Genes and gene pathways identified by IVIAT may play a role in virulence or pathogenesis during human infection, and may be appropriate for inclusion in therapeutic, vaccine or diagnostic applications.  相似文献   

14.
Oxygen enhances in vivo myocardial synthesis of poly(ADP-ribose)   总被引:1,自引:0,他引:1  
In vivo synthesis of poly(ADP-ribose) is demonstrated in cultured chick embryo heart cells. Cells grown with (14C) ribose incorporate 28 – 31% more radioactivity into poly(ADP-ribose) in 20% O2 (in which they divide more slowly) than in 5% O2. Reaction product was identified as poly(ADP-ribose) by its insensitivity to various enzymes and by its digestion with snake venom phosphodiesterase to phosphoribosyl-AMP and AMP. Poly(ADP-ribose) glycohydrolase activity was similar in 20% and 5% O2. Thus, both poly(ADP-ribose) polymerase activity (shown in an earlier study) and poly(ADP-ribose) increase in cells growing more slowly in 20% vs 5% O2. These data suggest that poly(ADP-ribose) metabolism participates in the regulation of heart cell division by O2.  相似文献   

15.
The role of glutathione (GSH) and chromium (V) in chromium (VI)-induced nephrotoxicity in mice was investigated at 24 h after K2Cr(VI)2O7 ip injection. Nephrotoxicity was assessed by measurements of relative kidney weight and serum urea nitrogen. Cr(VI) nephrotoxicity was accompanied by decreased renal GSH and glutathione reductase (GSSG-R) levels. Pretreatment with buthionine sulfoximine, an inhibitor of GSH biosynthesis, enhanced Cr(VI)-induced nephrotoxicity, and remarkably diminished kidney GSH and GSSG-R levels. In contrast, pretreatment with glutathione methyl ester, a GSH-supplying agent, prevented Cr(VI) from exerting a harmful effect on mouse kidney and restored kidney GSH level. Administration of a Cr(V) compound, K3Cr(V)O8, induced much higher toxicity in mouse kidney than Cr(VI), but it failed to diminish renal GSH level. Another Cr(V) compound, Cr(V)-GSH complex, and Cr(III) nitrate did not cause a nephrotoxic effect in mice. The mechanism of Cr(VI)-induced nephrotoxicity was explained using GSH and Cr(V).  相似文献   

16.
Current treatment modalities for malignant gliomas do not allow long-term survival. Here, we identify suberoylanilide hydroxamic acid (SAHA), an inhibitor of histone deacetylases (HDAC), as an effective experimental anti-glioma agent. Administration of SAHA to various glioma cell lines obtained from human, rat and mouse inhibited tumour cell growth in a range of 1-10 microm. This anti-glioma property is associated with up-regulation of the cell cycle control protein p21/WAF, as well as the induction of apoptosis. A novel tumour invasion model using slice cultures of rat brain corroborated the anti-glioma properties of SAHA in the organotypic brain environment. In this model, glioma invasion compromised adjacent brain parenchyma, and this tumour-associated cytotoxicity could be inhibited by SAHA. In addition, a 10-fold dose escalation experiment did not challenge the viability of cultured brain slices. In vivo, a single intratumoural injection of SAHA 7 days after orthotopic implantation of glioma cells in syngeneic rats doubled their survival time. These observations identify chromatin-modifying enzymes as possible and promising targets for the pharmacotherapy of malignant gliomas.  相似文献   

17.
18.
The pigeon esophageal smooth muscle shows "spontaneous" rhythmic bursts of spikes with increasing discharge frequency from pharynx to crop. There are no slow waves. The changes of the electric pattern induced by pharmacological administrations of atropine, prostigmine, hexamethonium and by asphyxia suggest that the electric activity is myogenic in origin. The innervation plays a role in the control of this activity and it is essential for the functional polarization.  相似文献   

19.
Benzodiazepine binding sites have generally been labelled with benzodiazepine agonists: (3H)flunitrazepam and (3H)diazepam in vivo. We studied the in vivo binding of the antagonist (3H)Ro 15-1788 in mice and compared it to the in vivo binding of (3H)flunitrazepam. For this in vivo labelling, mice were injected with labelled and unlabelled ligands. Animals were then sacrificed and bound radioactivity was measured after homogenization of the excised brain and filtration of the homogenate. (3H)Ro 15-1788 is a better tool than (3H)flunitrazepam for in vivo labelling of benzodiazepine receptors since 1) it labels specifically the central type binding sites, 2) injection of 4 times less (3H)Ro 15-1788 (50 microCi/kg) than (3H)flunitrazepam (200 microCi/kg) produced the same amount of bound radioactivity, 3) 70-90% of the total (3H)Ro 15-1788 present in the brain is membrane bound instead of 45-55% with (3H)flunitrazepam, 4) maximal binding of (3H)Ro 15-1788 is reached within 3 min, 5) only 5% of the membrane bound (3H)Ro 15-1788 is nonspecific instead of 15% for (3H)flunitrazepam.  相似文献   

20.
The addition of 2-deoxyglucose to tissue elicits an in vivo mitochondrial conformation response (contraction) that can be viewed ultrastructurally and is indicative of the phosphorylative capability of mitochondria. Utilizing this technique toxin from Bipolaris (Helminthosporium) maydis race T was found to penetrate leaf and root tissue of Texas male-sterile cytoplasm corn (Zea mays L. W64A) only slowly, but once in cells the toxin had a rapid deleterious effect on mitochondrial function. It is concluded that B. maydis (race T) toxin has effects on in vivo mitochondria similar to those reported after in vitro experimentation and that mitochondria are a primary site of toxin action. These observations are followed by the suggestion that susceptibility or resistance to B. maydis (race T) is conferred in corn by a cytoplasmically inheritable character associated with mitochondria.  相似文献   

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