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1.
Summary A reliable method for obtaining high-resolution R-banded chromosomes from lymphoblastoid cell lines is described. The cell cultures are subjected to S-phase synchronization in the presence of excess thymidine (300 g/ml) for 17 to 19 hr, followed by BrdU treatment (30 g/ml) for 6.5 hr. Prior to harvest, they are exposed to ethidium bromide (7.5 g/ml) for 1.5 hr and Colcemid (0.02 g/ml) for 30 min. Using this method, high-resolution R-banded chromosomes at the 550–850 band level were obtained with frequencies at high as 70% of all mitotic cells.  相似文献   

2.
The topical anti-inflammatory properties of flutrimazole, a new imidazole antifungal, have been evaluated. Flutrimazole inhibited mouse ear oedema induced by arachidonic acid, tetradecanoylphorbolacetate and dithranol, with IC50 values of 3.32, 0.55 and 2.42 mols/ear, respectively. Ketoconazole showed similar potency in arachidonic acid and dithranol models (IC50=3.76 and 2.41 mols/ear) whereas it was less active against tetradecanoylphorbol acetate (IC50=1.96 mols/ear). The standard anti-inflammatory sodium diclofenac was overall slightly more potent than antifungals (IC50=2.23, 0.57 and 0.57 mols/ear against arachidonic acid, tetradecanoylphorbol acetate and dithranol, respectively). Both 2% flutrimazole and 2% ketoconazole creams, applied topically, inhibited carrageenan-induced rat paw oedema by about 40%. Under the same conditions, 1% flutrimazole and diclofenac creams inhibited by 26 and 54%, respectively. Flutrimazole may work through the inhibition of 5-lipoxygenase, as it inhibited LTB4 production by human granulocytes with an IC50 value of 11 M (IC50 value for ketoconazole was 17 M), whereas ram seminal vesicle cyclooxygenase was only inhibited by 16% at a concentration of 25 M. Drugs such as flutrimazole, with dual anti-inflammatory/antifungal activity, may be advantageous in the treatment of topical fungal infections with an inflammatory component.accepted by I. Ahnfelt-Rønne  相似文献   

3.
Summary In Schizosaccharomyces pombe the frequency of mating-type (MT) switching is reduced by mutations in the swi genes. The ten hitherto known swi genes can be subdivided into three classes: Ia, Ib and II. Strains having swi5 (class Ib), swi9 (class II) and swi10 (class II) mutations do not only show reduced MT switching, but also exhibit an increased sensitivity to UV- and -rays. For that reason, 19 previously described rad genes were tested for their effect on MT switching. We found that swi9, rad10, rad16 and rad20 are allelic with each other indicating that the former allocation of these rad mutations to three different genes must have been erroneous. Among the remaining 16 rad genes examined, rad22 seems to be a new class II swi gene. The double mutants swi5 swi9 and swi5 swi10, but not swi9 swi10, are much more sensitive to radiation than the respective single mutants. Thus a cumulative increase in sensitivity occurs only if the mutants belong to different classes; previously the same correlation was found with regard to cumulative effects in MT switching.  相似文献   

4.
The separation in a sucrose gradient of the myofibrillary fraction of normal and autolyzed muscle tissue gave 4 components. During post-mortem destruction of the tissue there was observed a slight decrease of the myofibrillary fraction yield and also certain changes in the distribution of protein between different components. Under the selected conditions RNase activity was found in all 4 components. During the course of autolysis enzymatic activity increased in the whole myofibrillary fraction, as well as in the lysosomal-mitochondrial components of myofibrils.Research Laboratory, Ministry of Health of the USSR, Moscow. Translated from Buylleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 5, pp. 533–537, May, 1978.  相似文献   

5.
Zusammenfassung Die intestinalen-Galactosidasen von 4 lactose-toleranten, erwachsenen Mitteleuropäern wurden im Saugbiopsie-Gewebe nach Solubilisierung mit Triton X-100 in einem linearen Mannitol-Gradienten (5–20%) auf der Ultrazentrifuge bei 4°C und 44000 U/min getrennt. Bei 12stündiger Zentrifugation fanden sich 3 Fraktionen, von denen die beiden schneller sedimenticrenden Lactose spalten. Alle 3 Fraktionen hydrolysieren p-Nitrophenyl--Galactosid. Die 3 isolierten-Galactosidasen entsprechen wahrscheinlich der neutralen Bürstensaum-Lactase, der sauren lysosomalen Lactase und einer cytoplasmatischen Hetero--Galactosidase.  相似文献   

6.
This study presents definitive dimensions of the gametocyteHepatozoon canis using image analysis technology. The mean length and width of the gametocyte was found to be 11.42 ,m and 5.39 m, respectively. The mean area of the gametocyte was found to be 45.88 m2. The average perimeter of the gametocyte was 28.92 m. The results compare well with some previous measurements using light-microscopic techniques.  相似文献   

7.
InXenopus follicular oocytes, activation of muscarinic receptors evokes a slow potassium current (H-response); a similar current is evoked by intracellular injection of cyclic guanosine 3,5-monophosphate, cGMP (Dascal et al. 1984). We have tested the hypothesis that cGMP may be the second messenger that mediates the opening of K channel by acetylcholine (ACh). ACh elevated the intracellular level of cGMP with a time course similar to that of the development of the muscarinic H-response; maximal increase in cGMP concentration above the control was about 0.2 pmole/oocyte. The amount of injected cGMP that produced a detectable K current (threshold dose) varied between 0.5 and 3 pmole/oocyte. At low doses of cGMP, the slope of log dose-log response curve was about 2.5, suggesting involvement of a biochemical process with a positive cooperativity of at least 3. Higher doses of cGMP evoked, in addition to the outward current, an irregular, rapidly developing, long-lasting inward current, that never reached amplitudes comparable to those of ACh-evoked Cl currents. The K current elicited by cGMP was insensitive to elevation or depletion of external Ca. It was potentiated by isobutylmethylxanthine (IBMX). ACh strongly inhibited the cGMP-evoked K current when applied at the plateau of the latter. 4-Phorbol 12,13-dibutyrate (PDBu) (1 M) rapidly and completely inhibited the cGMP response. It is concluded, that most of the results presented in this report contradict the hyothesis that cGMP is the intracellular mediator of ACh-induced changes in membrane conductance in the oocytes.Abbreviations ACh acetylcholine - cAMP cyclic adenosine 3,5-monophosphate - cGMP cyclic guanosine 3,5-monophosphate - EGTA ethylenediaminetetraacetic acid - Hepes N-2-hydroxyethyl-piperazinc-N-2-hydroxypropanesulphonic acid - IBMX 3-isobutyl-l-methylxanthine - IP3 inositol 1,4,5-trisphosphate - PDBu 4-phorbol 12,13-dibutyrate  相似文献   

8.
The blocking properties of the neurotoxic peptide -conotoxin GVIA (-CgTX), on neuronal Ca channels were investigated. In line with previous reports (Feldman et at. 1987; McCleskey et al. 1987), we found that micromolar concentrations of the toxin block selectively and persistently the high-threshold Ca channels of chick sensory neurons. The block by -CgTX could be partially relieved in low [Ca2+]0 (<1 M) toxin-free solutions, allowing Na ions to flow through open high-threshold Ca channels. Ca currents through these channels, however, remained permanently blocked on returning to normal Ca2+ toxin-free solutions. Also neurons which were preincubated with -CgTX in low Ca2+ (6 mM EGTA) failed to show high-threshold Ca currents during washing with normal Ca2+. Thus, appearance of Na currents through Ca channels in CgTX-pretreated cells was neither a consequence of unbinding of the toxin from its receptor site nor due to an interaction of EGTA with bound -CgTX. Na currents in CgTX-pretreated cells could be reversibly suppressed by bath applications of verapamil or by further addition of the toxin. At variance with Ca currents, block of Na currents by -CgTX was faster and reversible (K D 0.7 M). Our data are consistent with the idea that neuronal Ca channels are in different conformational states when permeable to Ca2+ or Na+ ions and that -CgTX depresses persistently ion permeation primarity in the Ca-permeable state.  相似文献   

9.
In the presence of glycerol, EcoRl restriction endonuclease hydrolyzes DNA into a larger number of fragments than under ordinary conditions. On the addition of glycerol to 50% concentration, this enzyme begins to act by what is called the EcoRl' type of restriction, which was producible experimentally only by reducing the ionic strength and increasing the pH of the solution. However, under these extremal conditions, the enzyme is quickly inactivated and does not give reproducible results, especially during the hydrolysis of high-molecular-weight DNA. The conditions found for manifestation of EcoRl' activity yield reproductible results, which is essentially equivalent to the discovery of a new restriction endonuclease.The nomenclature of the restriction enzymes follows that of Smith and Nathans [6].Laboratory of Biochemistry, D. I. Inanovskii Institute of Virology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR S. S. Debov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 7, pp. 46–48, July, 1977.  相似文献   

10.
The hearts of rats carried on board the biosatellites Kosmos-605 and Kosmos-782 were studied histologically and histochemically. A long space flight (up to 22 days) did not cause any significant structural or metabolic changes to develop in the heart. The absolute weight of the heart also was unchanged. A transient increase in phosphorylase activity in the myocardium of the rats 10–11 h after the end of the flight was due to stress resulting from exposure to the combination of extremal factors accompanying landing of the satellite.Institute of Medico-Biological Problems, Ministry of Health of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 485–486, April, 1977.  相似文献   

11.
Yeast mitochondria were found to contain a novel topoisomerase-like activity which required nucleoside di- or tri-phosphates as a cofactor. ADP supported activity as effectively as ATP and the optimal concentration for each was approximately 20 M. None of the other standard ribo- or deoxyrib-onucleotides could fully substitute for either ADP or ATP. The non-hydrolyzable ATP analogs, adenosine-5-0-(3-thiotriphosphate) (ATP--S), adenylyl (, -methylene) (AMP-PCP), and andenyl-imidodiphosphate (AMP-PNP) also supported activity suggesting that the nucleotide cofactor regulated topoisomerase activity rather than serving as an energy donor in the reaction. The mitochondrial topoisomerase activity relaxed both positively and negatively supercoiled DNA. It was not inhibited by concentrations of ethidium bromide up to 2 g/ml nor by either nalidixic or oxolinic acids; novobiocin, coumermycin, and berenil inhibited the activity. Genetic and biochemical analysis of the mitochondrial topoisomerase activity indicated that it was not encoded by the nuclear TOP1, TOP2, and TOP3 genes.  相似文献   

12.
As the most commonly used drug that can modulate both metabolic and immune pathways, ethanol is evaluated in this report as a regulator of tumor necrosis factor (TNF) production in human peripheral blood monocytes (M) in combination with a variety of stimuli. While acute ethanol treatment did not induce TNF in M, it was a potent down-regulator of M TNF production whether induced by the combination of interferon- plus muramyl dipeptide (MDP) (P<0.001), lipopolysaccharide (LPS) alone (P<0.01), or interferon- plus LPS. Down-regulation of M TNF by ethanol was dose dependent and statistically significant in the biologically relevant, 25–150 mM, ethanol concentration range. We also demonstrate that these ethanol concentrations did not affect M viability. TNF down-regulation by ethanol was most effective when ethanol was administered 4 hr prior to MDP stimulation; however, it was also effective—though to a lesser extent—if it was added at the time of MDP stimulation. Furthermore, ethanol also down-regulated TNF production of thein vivo preactivated M of trauma patients, which produce hyperelevated levels of TNF. We have previously shown that the majority of posttrauma elevated M TNF is produced by the M subpopulation expressing high-affinity type I Fc receptors (FcRI). When the FcRI cross-linking-stimulated M subpopulation was treated with acute ethanol, TNF production was suppressed again both inin vivo preactivated M of trauma patients and in M of normal controls. In experiments utilizing cyclooxygenase inhibitor, we also demonstrate that ethanol has a direct, prostaglandin E2-independent, effect on M TNF production. These results demonstrate that acute ethanol exposure has the potential to down-regulate M production of TNF significantly regardless of the TNF-inducing stimulus. Decreased capacity of M to produce TNF might, therefore, contribute to the immunological and metabolic abnormalities described after ethanol uptake.  相似文献   

13.
Zusammenfassung Ausgehend von den UntersuchungenRössles zum Formenkreis der rheumatischen Gewebsveränderungen, wird an Hand von 4 eigenen Fällen die Problematik der morphologischen Differentialdiagnose zwischen rheumatischer Arteriitis, Periarteriitis (Panangiitis) nodosa und Thrombangitis obliterans unter Berücksichtigung der Literatur aufgezeigt. Mit der morphologischen Definition der verwendeten Begriffe fibrinöse Entzündung und proliferierende und granulierende Angiitis wird versucht, die drei Formen der Gefäßwandentzündung morphologisch abzugrenzen. Die überschneidungen der morphologischen Symptome und die Kombinationsformen werden aus Beschreibung und Abbildung einschlägiger veröffentlichter Fälle aufgezeigt. Aus dem Nachweis dieses Schrifttumsvergleichs und dem der Differentialdiagnose der 4 eigenen Fälle wird gefolgert, daß bei solchen nicht-klassischen Gefäßentzündungen die Annahme von Kombinationsformen richtiger ist als die immer stärkere Erweiterung des sog. rheumatischen Formenkreises.
Summary With reference to the investigations ofRössle On the Classification of the Rheumatic Tissue Changes, the problems that are associated with the differential diagnosis of rheumatic arteritis, periarteritis (panangiitis) nodosa, and thromboangiitis obliterans are discussed, exemplified by the report of four cases, and by a review of the literature. By applying the morphological criteria of fibrinous inflammation, proliferative and granulomatous angiitis, an attempt is made histologically to differentiate these three forms of inflammation of the vascular wall. The overlapping of the morphological criteria and the combined forms that mav occur are illustrated in the four cases reported. As shown by comparing the cases in the literature, and as exemplified by the differential diagnosis of the four cases, the inference is made, that with such types of non-classical vascular inflammation, it is better to refer to combined forms than to the more diffuse so-called rheumatic classification.
  相似文献   

14.
The mutants musK to musS of Aspergillus nidulans are sensitive to methyl-methanesulfonate (MMS) and several of them are meiotic-defective and alter mitotic recombination frequencies. All were found to be cross-sensitive to 4-nitro-quinoline-N-oxide (4-NQO) but unexpectedly none of them was hypersensitive to -rays and few to UV light. Double mus;uvs mutants were constructed to test for interactions with uvs mutations of the four epistatic groups of Aspergillus, UvsF, UvsC, UvsI, and UvsB. All meiotic-defective mus mutations caused some lethal interactions, usually with uvsF. None of them showed epistasis with UvsF or UvsB group mutants and one, musO, may represent a new group. Three mus mutations that affect recombination were assigned to the UvsC group, namely musN and K, and also musL which is recombination-defective and closely resembles uvsC. While uvsC mutants are mutators and lack UV-mutagenesis, most mus mutants had no effects on mutation. Only musR, which appeared epistatic with uvsI, showed reduced UV-reversion frequencies similar to uvsI. The recombination-proficient mus mutants appeared to be epistatic with more than one group, but in several cases sensitivities were slight and overlaps insufficient to obtain corroborating results with MMS and 4-NQO.  相似文献   

15.
The 5S ribosomal (r) RNA genes encode a small (120-bp) highly-conserved component of the large ribosomal subunit. The objective of the present research was to study the molecular and cytogenetic organization of the chicken 5S rDNA. A predominant 2.2-kb gene (5S) consisting of a coding and intergenic spacer (IGS) region was identified in ten research and commercial populations. A variant gene repeat of 0.6kb (5S) was observed in some of the populations. Genetic linkage analysis and cytogenetic localization by fluorescence in-situ hybridization assigned the 5S rDNA to chromosome 9. The 5S rDNA array was determined to be 80.2±7.0kb upon electrophoretic sizing following EcoRV digestion. Sequence analysis of 5S IGS regions revealed considerable conservation between chicken subspecies (98.4% identity) as well as homology with vertebrate Pol III promoter and regulatory sequence motifs. Minor intraindividual sequence variation within 1000bp of IGS was observed in four cloned Red Jungle Fowl (Gallus gallus gallus) 5S repeats (95.5% identity in this region). Sequence comparisons between IGS regions of 5S and 5S genes indicated two short continuous (>20bp) and many short non-continuous homologous regions as well as other conserved features such as promoter and termination motifs.  相似文献   

16.
Two larval foraging strategies inDrosophila melanogaster were identified, rover and sitter. Rovers traverse a large area while feeding whereas sitters cover a small area. The difference between rovers and sitters was analyzed genetically by chromosomal substitutions between isogenic stocks. Differences in larval locomotor behavior (crawling behavior) can be attributed to the second chromosome, the rover strategy being dominant over the sitter strategy. Differences in feeding rate (shoveling behavior) are affected additively by both the second and third chromosomes. Natural populations ofDrosophila larvae were sampled three times over a 2-month period; rovers and sitters were at constant frequencies in these populations. The two foraging strategies are discussed in the light of resource utilization in environments where food is distributed continuously or discontinuously.  相似文献   

17.
The effect of morphine and trimeperidine on the concentration, uptake, and liberation of noradrenalin (NA) in the rat myocardium was investigated. Trimeperidine lowers the NA level in the myocardium. Morphine does not affect the liberation of NA-14C from the isolated perfused heart, whereas trimeperidine significantly increases it, affecting both the slow and the rapid release of the mediator. Trimeperidine does not affect the uptake of NA-14C by the perfused heart but morphine significantly lowers it. Competition between morphine and NA is characterized by an incomplete inhibition effect: Morphine and NA mutually affect the affinity of each other for the receptor and their interaction depends on their relative concentrations.Laboratory of Pharmacology of the Cardiovascular System, Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 11, pp. 1345–1347, November, 1976.  相似文献   

18.
Summary The author investigated the nature of the substances which influenced the skeletal muscle in stimulation of the sympathetic nerve. It was established that by stimulating the sympathetic nervous system, active substances appear in the perfusate of the frog's skeletal muscle. Evaporation of the perfusate, with subsequent calcination of the dry residue and its disolution in distilled water, does not remove the positive effect exerted on the frog's heart. Of the ions tested (Na, Mg, and Ca), the picture analogous to the action of the sympathetic perfusate is obtained only in the case of Ca.From the Pharmacological Laboratory (Head-Professor N.P. Sinitsyn) S.M. Kirov Gor'kii Medical InstitutePresented by Active member of the AMN SSSR V. V. Zakusov  相似文献   

19.
The B mating type of the basidiomycete fungus, Schizophyllum commune is determined by two, tightly linked, multi-specificity (also called multi-allelic) loci: B and B. A plasmid library was used in DNA-mediated transformation to obtain transformants that displayed B-directed development. Plasmids that conferred B1 and B1 mating-type specificities were rescued from the transformants. Fragments of DNA from each plasmid hybridized to genomic DNA from the strain used to make the plasmid library; however, they did not hybridize, or hybridized only weakly, to genomic DNA from strains with mating-type specificities different from B1 or B1. The cloned fragments are presumed to correspond to active regions of each B mating-type locus.  相似文献   

20.
The level of bioactive transforming growth factor- (TGF-) was measured in serum from patients with chronic fatigue syndrome (CFS), healthy control subjects, and patients with major depression, systemic lupus erythematosis (SLE), and multiple sclerosis (MS) of both the relapsing/remitting (R/R) and the chronic progressive (CP) types. Patients with CFS had significantly higher levels of bioactive TGF- levels compared to the healthy control, major depression, SLE, R/R MS, and CP MS groups (P < 0.01). Additionally, no significant differences were found between the healthy control subjects and any of the disease comparison groups. The current finding that TGF- is significantly elevated among patients with CFS supports the findings of two previous studies examining smaller numbers of CFS patients. In conclusion, TGF- levels were significantly higher in CFS patients compared to patients with various diseases known to be associated with immunologic abnormalities and/or pathologic fatigue. These findings raise interesting questions about the possible role of TGF- in the pathogenesis of CFS.  相似文献   

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