Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Formamides”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,801 records · Page 100Linked to original sources
PubMed1990

[Comparison of pro-edematous effects of 2 calcium antagonists in bilaterally nephrectomized rats].

Chronic treatment with dihydropyridines and to a lesser extent other calcium antagonists often cause peripheral edema without fluid retention. To test the possibility that calcium antagonists affect extracellular fluid partition between plasma and interstitium, we compared the effects of a benzothiazepine derivate diltiazem, a dihydropyridine derivate nicardipine and vehicle in binephrectomized anesthetized rats by measuring changes in hematocrit and plasma protein concentration. Forty minutes infusion of low dose of nicardipine and diltiazem (0.1 and 10 micrograms/kg/min respectively) had no significant effect on blood pressure (-2 +/- 2 and -4 +/- 3% respectively); nicardipine increased hematocrit by 5.6 +/- 0.5% (p less than 0.05); while diltiazem had no significant effect as compared to the vehicle (+1.5 +/- 0.3 and +1.5 +/- 0.3% respectively). The calculated loss of plasma volume during nicardipine infusion was 9.2 +/- 0.8% as compared to 2.5 +/- 0.6% and 2.7 +/- 0.6% in rats receiving diltiazem and vehicle respectively. Infusion of higher doses of nicardipine and diltiazem (1 and 100 micrograms/kg/min respectively) decreased blood pressure by 21 +/- 2 and 19 +/- 2% while the changes in hematocrit were not different than those observed with with the lower doses (5.5 +/- 0.6 and 1.4 +/- 0.3% respectively). To document and localize an alteration in vascular leak of proteins induced by the drugs, albumin-bound Evans Blue (EB) extravasation was measured spectrophotometrically in different tissues after extraction by formamide. Nicardipine but not diltiazem increased vascular permeation of EB-albumin in skeletal and cardiac muscle. No change was observed in brain, liver, spleen as compared to rats receiving the vehicle.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗
PubMed1990

[Evaluation of the critical surface tension (gc) of composite resins].

The purpose of this study was to assess the surface free energy of a series of composite resin restorative materials, utilizing the concept of critical surface tension (yc). Cylindrical samples of 20 mm diameter and 2 mm in thickness were prepared from 4 microfilled, 3 hybrid and 6 small particle composite resins. The critical surface tension was determined by contact angle measurements on 1000 grit ground surfaces. A Zisman series of homologous liquids was used (Water, Glycerol, Formamide, Thiodiglycol, Dilodormethane, I-Bromonapthalane). The recorded yc means were 30.000-42.600 dyn/cm for microfilled, 42.47-44.68 dyn/cm for hybrid and 42.19-49.20 dyn/cm for small particle composites. In all the cases the work of wetting was primary attributed to non polar and dispersion forces. The type and the concentration of the reinforcing fillers is the major factor influencing yc, especially in the presence of hydrophylic particles like Ba. Microfilled materials showed decreased wetting efficiency. Hydrophobic monomers do not provide any significant advantage on the wettability of polished composite surfaces.

Composite Resins↗
PubMed1979

A rapid method for detecting and mapping homology between heterologous DNAs. Evaluation of polyomavirus genomes.

A new approach for evaluating homologous sequences among related DNAs is presented. Conventional filter hybridization techniques are employed at 35 degrees C in a range of formamide concentrations in order to perform annealings at effective temperatures as low as Tm -50 degrees C which permits the detection of regions of homology with as much as 33% base mismatch. Under such nonstringent conditions, high levels of specific annealing can be obtained at plateau levels. In combination with the Southern "blotting" technique (1975), this approach can be used to perform biochemical heteroduplex melting experiments. The homology among the genomes of the murine polyoma virus (Py), the simian virus 40 (SV40), and the human papovavirus BK was evaluated using this new methodology.

DNA, Viral↗
PubMed1990

Protection from carcinogen-induced murine bladder carcinoma by interferons and an oral interferon-inducing pyrimidinone, bropirimine.

Interferons (IFNs) have established activities as antivirals and inhibitors of viral and transplantable tumors. To establish whether IFNs or their inducers can affect induction of carcinogenesis in vivo, the bladder-specific carcinogen N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide (FANFT) was administered in the diet at 0.11 or 0.13% (w/w) to female C3H/He mice beginning at 7 weeks of age. Mice treated with the IFN-inducing bropirimine [2-amino-5-bromo-6-phenyl-4(3H)-pyrimidinone] i.p. twice a week for 14 weeks starting on day 30 of start of FANFT feeding developed fewer transitional cell carcinomas (TCC) than mice treated with the vehicle. Bropirimine (200 mg/kg twice a week) orally resulted in even greater effectiveness: 6 of 43 bladders with TCC for bropirimine-treated mice versus 24 of 39 for control glycine buffer-treated mice (P less than 0.01, x2 test). Mice treated i.p. daily on days 29 through 210 with 5,000 units of beta interferon (specific activity, 2.0 x 10(8) units/mg) had 0 of 15 TCC while control mice had 7 of 13 TCC (P less than 0.001). Bladders of untreated mice were also significantly heavier than those of beta interferon- or bropirimine-treated mice. This dose of IFN treatment was confirmed as effective in a second experiment, in which mice were treated daily on days 30-223 with 5,000 units alpha/beta interferon (specific activity, 1.2 x 10(7) units/mg). This resulted in 4 of 25 bladders with TCC versus 24 of 39 for control mice (P less than 0.001). A higher dose of IFN (50,000 units alpha/beta interferon daily) was toxic; 24 of 30 mice died within 2 months. IFN and an IFN inducer, bropirimine, inhibited development and progression of FANFT-induced bladder TCC in vivo and thus may have roles as chemopreventive modalities.

Animals↗
PubMed1985

Fluorescence microscopical hybridocytochemistry.

A new method has been developed to detect RNA-DNA hybrids in situ by fluorescence microscopy. This overcomes some of the disadvantages of autoradiographical detection of in situ hybridization, notably the low resolution and long exposure times needed. A procedure to label RNA at its 3'-terminus with a fluorochrome molecule has been developed. The optimal conditions for the cytochemical hybridisation reaction of this fluorochrome-labeled RNA were investigated using a model consisting of Sepharose beads to which nucleic acids has been bound. With RNA labeled both with 3H and rhodamine the hybridization reaction could be studied both biochemically by scintillation counting and cytochemically by microfluorometry. The fluorochrome-RNA bond was found to be unstable at higher temperatures. Therefore, the hybridization reaction had to be performed at room temperature in formamide-containing buffers. With fluorochrome-labeled complementary RNA kinetoplast DNA in Crithidia luciliae, adenovirus-5 DNA in infected KB cells and 5S rRNA, tRNA and cloned histone genes in polytene chromosomes of Drosophila could be localised. An immunocytochemical amplification method was developed that increased the sensitivity of the direct method. Several recently developed hybridocytochemical methods based on a combination of a hybridisation reaction in the first layer followed by immunocytochemical second layers, are described. The prospects of the application of the hybridocytochemical techniques in biomedical research, such as gene localisation and virus diagnosis, are discussed.

Autoradiography↗
PubMed1986

Increased permeability of microcarrier-cultured endothelial monolayers in response to histamine and thrombin. A model for the in vitro study of increased vasopermeability.

The permeability response of endothelial monolayers to some "direct-action" type mediators of vasopermeability were studied in vitro. Endothelial cells, cultured to confluence on denatured collagen-coated dextran microcarriers or gelatin microcarriers, prevented staining of the microcarriers with Evans blue dye. Increases in staining, as determined by the spectrophotometric quantitation of the dye after extraction from the microcarriers with formamide, occurred after treatment of human umbilical vein endothelium with histamine (10(-5) M) or thrombin (0.1 U/ml). These increases in monolayer permeability were reversible. Neither bradykinin nor serotonin had any effect in this system. Endothelial monolayers cultured this way consistently stained with silver nitrate at the cell junction areas. Monolayer response to histamine was characterized morphologically by small openings which occurred randomly along the cell junctions; while with thrombin, the spaces, which had developed at junctions, occurred to a greater extent. Prostaglandin E1 (30 microM) and isoproterenol (10 microM), in the presence of 3-isobutyl-1-methylxanthine (1 mM), partially inhibited histamine- and thrombin-mediated changes in permeability. This model responds to certain vasopermeability-altering agents in a manner similar to that of the microcirculation. These studies support the concept that the vasopermeability enhancing effect of histamine in vivo results, in part, from a direct effect on the endothelium.

1-Methyl-3-isobutylxanthine↗
PubMed1987

Efficacy of antitumor chemotherapy in C3H mice enhanced by the antiangiogenesis steroid, cortisone acetate.

The effect of "antiangiogenesis" therapy using cortisone acetate (CA) with or without heparin on tumor growth as well as in combination with chemotherapy was investigated. C3H mice were implanted intradermally with N-[4-(5-nitro-2-furyl)-thiazolyl]formamide induced undifferentiated transitional cell carcinoma, MBT-2, in the right flank. The treatment was initiated 9 to 10 days after tumor inoculation. Daily injections of CA (250 mg/kg s.c.) suppressed tumor growth significantly in a dose dependent fashion. Administration of heparin (Elkins-Sinn) at the concentration of 200, 400, or 1000 units/ml in drinking water for 3 to 6 days was neither additive nor detrimental to the effect of CA. Chemotherapy was combined with CA; 3 days of administration of 250 mg/kg of CA in tapering doses was used. The chemotherapeutic agent was injected once 24 h before the initial CA. Combinations of chemotherapy (Adriamycin, 2.5-7.5 mg/kg i.v; cisplatin, 3-9 mg/kg i.p.; cyclophosphamide, 50-150 mg/kg i.p.; cis-(diammino)(1,1-cyclobutanedicarboxylate)platinum(II) (JM-8), 60-150 mg/kg i.p.; mitomycin C, 3-4.5 mg/kg i.p.) with CA showed additive suppression of tumor growth. Mice tolerated chemotherapy alone, CA alone, and both in combination. CA combined with JM-8 was not tolerated. Mice tolerated 100 to 150 mg/kg of JM-8, whereas the addition of CA to JM-8 resulted in a 66% (6 of 9) to 89% (8 of 9) mortality rate. CA at a concentration of 5 and 25 micrograms/ml showed no direct cytotoxic activity against MBT-2 cells in vitro. However, 3 days of administration of 250 mg/kg of CA inhibited tumor angiogenesis generated by MBT-2 cells in C3H mice using a dorsal air sac assay. The data suggest that CA alone inhibits tumor angiogenesis in C3H mice and that antiangiogenesis therapy enhances the antitumor efficacy of chemotherapeutic agents without increasing host toxicity (except for JM-8).

Animals↗
PubMed1987

Influence of phosphatidylserine on endogeneous RNA synthesis in isolated rat liver nuclei.

The possible involvement of anionic phospholipids in the transcriptional process was studied in isolated rat liver nuclei synthesizing RNA in the presence of phosphatidylserine, which was employed in the form of multillamellar liposomes as a means of delivering the lipid to the nuclei in aqueous medium. The divalent ion requirement for RNA synthesis and the properties of the incubation mixture were not significantly modified by the phospholipid, which increased the rate and the extent of the incorporation of 3H-UMP without changing the endogeneous degradation pattern of the product or affecting the activity of a particular RNA polymerase, as indicated by the sensitivity to amanitin. The thin layer chromatography analysis of the alkaline hydrolysates of the RNA showed that the stimulation involved an increase of the total polyribonucleotide elongation rate. The size of the product was essentially unchanged in the presence of phosphatidylserine, as demonstrated by the qualitative overlapping of the sedimentation profiles of control and lipid treated samples in formamide-sucrose gradients. The release of the H1 fraction from intact nuclei occurring with phosphatidylserine indicated that the DNA template availability was increased by a partial removal of the restrictions imposed by histones, as suggested also by the comparison with heparin and Sarkosyl. These evidences, together with the data accumulated on the occurrence of lipids in chromatin and nuclear matrix, and on their changes related to cell growth, differentiation and malignant transformation, allow a better definition of the role that phospholipids might play in regulating the DNA template availability in the cell.

Amanitins↗
PubMed1989

[A chromatographic method of determining serotonin and histamine in a single sample of biological material].

Serotonin and histamine are important components of neurohumoral regulation. The biologic and fluorometric methods currently used for their measurements are labor-consuming and involve the use of unavailable reagents and expensive equipment. The authors suggest a sensitive simplified technique for serotonin and histamine measurements in a small volume of the biologic material (tissue and blood). The procedure is as follows: serotonin and histamine are isolated by thin-layer chromatography, the obtained samples are treated with alloxan in dimethyl formamide medium, and the stained solutions are examined in spectrophotometer. The suggested method is highly specific and sensitive, simple, makes use of Soviet equipment and of available reagents, this recommending it for clinical biochemical, as well as for experimental studies.

Animals↗
PubMed1989

[Liquid transfers induced by a calcium antagonist and the atrial natriuretic peptide in binephrectomized rats].

Peripheral edema without fluid retention is a common side effect of treatment with calcium antagonists (CA). The possibility that CA may alter extracellular fluid partition between plasma and interstitium, as suggested for atrial natriuretic peptide (ANP) was explored in binephrectomized anesthetized rats by measuring changes in hematocrit and plasma protein concentration during infusion of synthetic 103-126 ANP (Wy 47.663) and the dihydropyridine derivate nicardipine. After a forty minutes infusion of ANP (1 microgram/kg/mn), hematocrit and plasma protein increased 9.1 +/- 0.3 and 3.9 +/- 0.3 p. 100 respectively; the calculated loss of plasma volume during ANP infusion was 14.5 +/- 1.1 p. 100 as compared to 3.9 +/- 0.6 p. 100 in rats receiving vehicle only. Infusion of nicardipine at 1 microgram/kg/mn increased hematocrit by 5.7 +/- 0.2 p. 100 (corresponding to a 9.1 +/- 0.9 p. 100 decrease in plasma volume), and plasma proteins by 3.7 +/- 0.2 p. 100. To document and localize an alteration in vascular leak of proteins induced by the drugs, albumin-bound Evans blue (EB) extravasation was measured spectrophotometrically in different tissues after extraction by methyl-formamide. Both ANP and nicardipine increased vascular penetration of EB-albumin, mainly in skeletal and cardiac muscle; no changes was observed in brain, liver, spleen as compared to rats receiving the vehicle; ANP but not nicardipine increase EB-albumin permeability in intestine. These results suggest that nicardipine as well as ANP reduce plasma volume by increasing vascular leak of fluids and macromolecules.

Animals↗
PubMed1989

Hen oviduct N alpha-acetyltransferase is a ribonucleoprotein having 7 S RNA.

Hen oviduct N alpha-acetyltransferase was clarified to have a nucleic acid as an existing constituent by the following three results: (i) an ultraviolet absorption spectrum of the purified N alpha-acetyltransferase free of S-acetyl coenzyme A (Ac-CoA) had an absorption maximum at 260 nm. (ii) A nucleic acid band stained with ethidium bromide was detected on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. (iii) An ethidium bromide band co-migrated with a fluorescent band of the protein treated with N-(7-dimethylamino-4-methylcoumarinyl)maleimide, a reagent specific for thiol groups, on polyacrylamide gel electrophoresis in the absence of sodium dodecyl sulfate. N alpha-Acetyltransferase lost its activity partially or completely by digestion with bovine pancreatic RNase A, Staphylococcus aureus nuclease, or proteinase K, showing that both the nucleic acid and the protein subunit were necessary for the enzyme activity. The nucleic acid component was identified as an RNA but not a DNA because the RNase T2 digest of the nucleic acid was composed of four 3'-ribomononucleotides and completely separated from 3'- and 5'-deoxyribomononucleotides on TLC. The chain length of the nucleic acid of 260 nucleotides estimated by formamide-polyacrylamide gel electrophoresis was calculated to be about 83,000 of the molecular weight. The contents of RNA (35.0%) and protein (65.0%) in N alpha-acetyltransferase determined on weight basis corresponded reasonably well to the contents of RNA (34.4%) and protein (65.6%) calculated based on the assumption that N alpha-acetyltransferase consisted of one molecule of 7 S RNA (Mr 83,000) and two identical Mr 79,000 protein subunits. The total molecular weight (241,000) of the holoenzyme calculated based on the above result was identical to the molecular weight (240,000) of N alpha-acetyltransferase estimated by Sepharose 6B gel filtration.

Acetyltransferases↗
PubMed1989

Potential bile acid metabolites. 14. Hyocholic and muricholic acid stereoisomers.

The complete set of the eight theoretically possible stereoisomeric 3,6,7-trihydroxy-5 beta-cholanic acids, four of which are new, related to hyocholic and muricholic acids were prepared from chenodeoxycholic acid. The principal reactions used were 1) cis-dihydroxylation of delta 6-compounds with osmium tetroxide/N-methylmorpholine N-oxide; 2) trans-dihydroxylation of 6 alpha, 7 alpha-epoxy compounds with boron trifluoride etherate in N,N-dimethyl-formamide; 3) inversion of equatorial 3 alpha-hydroxylated compounds to the corresponding 3 beta-epimers with diethyl azodicarboxylate/triphenylphosphine/formic acid; and 4) stereoselective reduction of 7-keto derivatives with zinc borohydride (or sodium borohydride) and by metallic potassium/tert-amyl alcohol.

Bile Acids and Salts↗
PubMed1989

Unusually large interferon-alpha-like mRNAs and high expression of interleukin-6 in human fetal annexes.

Endogenous interferons (IFNs) with antiviral activity have been detected in human fetal annexes, without any apparent induction. Some are of unusually high molecular weight and antigenic properties (Duc-Goiran P., Robert-Galliot, B., Lopez, J., and Chany, C. (1985) Proc. Natl. Acad. Sci. U.S.A. 82, 5010-5014). We study here the expression of IFN genes from the three antigenically distinct groups, in placental tissues taken during third-trimester pregnancies. We show by Northern blot analysis with RNA probes that IFN-alpha-like transcripts correlate with the presence of functionally active protein, purified by immunoaffinity chromatography. We fractionate on a formamide sucrose gradient, identify, and characterize a large 4.3-kb IFN-alpha-like transcript, which may be specifically expressed during fetal development. Despite the absence of IFN-beta transcript, a protein with an antiviral activity which was neutralized with a polyclonal anti-IFN-beta serum was detected in the placenta and could be related to a beta-like IFN. Besides IFNs, various growth factors and cytokines can be found in the placenta. We report here the presence of interleukin-6 expressed at high levels in fetal annexes. The coexpression of Interleukin-6 and endogenous IFNs suggests that they play an important role during development.

Amnion↗
PubMed1985

Effects of changes in motor unit size on transmitter release at the frog neuromuscular junction.

The dependence of transmitter release and synaptic effectiveness on the size of a neuron's peripheral field was studied using neuromuscular junctions in sartorius muscles of adult frogs (Rana pipiens). The size of the peripheral field (motor unit size) was reduced by crushing the sartorius nerve and surgically removing half of the muscle fibers. Synapses thus formed were compared with those formed when crushed nerves reinnervated intact whole muscles, as well as with synapses in normal unoperated muscles. Indirect observations suggested that all motor axons participated in reinnervation and that motor unit size was indeed smaller in half-muscles. Synaptic safety margins, as measured by the sensitivity of nerve stimulus-evoked twitching to low Ca2+, were substantially higher in muscles with reduced motor units. These higher safety margins were due to enhanced evoked transmitter release. In Ringer solution containing Mg2+ and lowered Ca2+, total evoked release and evoked release per unit nerve terminal length were approximately 2-fold higher in muscles with reduced motor units, when studied 7 to 18 weeks postoperatively. A similar difference was seen when unblocked release was measured in a normal physiological solution, after blocking excitation-contraction coupling and muscle fiber action potential generation with formamide. Miniature endplate potential frequency in half-muscles was 2 to 3 times higher than in controls when tested in normal physiological solution, but was not significantly different in low Ca2+, Mg2+-containing solution. By 34 weeks postoperatively, there was no longer a difference in evoked release, even though the difference in motor unit size persisted.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Aberrant cyclic adenosine 3':5'-monophosphate metabolism in cultures of tumorigenic rat urothelium.

The cyclic adenosine 3':5'-monophosphate (cyclic AMP) metabolism of stratified normal rat urothelium propagated in vitro on a floating collagen matrix was characterized and used as a basis for identifying potential biochemical lesions in tumorigenic cell lines. The four neoplastic urothelial cell types studied (AY-27, AY-32, AY-33, and AY-34) were derived from Fischer 344 rats fed the carcinogen N-[4-(5-nitro-2-furyl)-2-thiazolyl]formamide. Epinephrine or prostaglandin E1 caused a rise in the cyclic AMP content of normal cultures which was potentiated in the presence of the cyclic nucleotide phosphodiesterase inhibitor 1-methyl-3-isobutylxanthine or by forskolin, a diterpene activator of adenylate cyclase in intact cells. The expected, normal profile of cyclic AMP accumulation in response to beta-adrenergic receptor agonists was epinephrine greater than norepinephrine greater than phenylephrine. By every measure, the tumorigenic AY-27 cells demonstrated an overall decrease of functional adenylate cyclase activity. This was evidenced most by the low accumulation of cyclic AMP observed in response to forskolin. While prostaglandin E1 elicited a heightened cyclic AMP level in these cells, their vanishingly low response to catecholamines also suggested a potential lack of functional beta-adrenergic receptors. Cyclic AMP phosphodiesterase activity was elevated in soluble enzyme preparations obtained from cultures of AY-27 cells. Observations of AY-32 cells were diametrically opposite to the findings with AY-27 cells. In AY-32 cells, prostaglandin E1 receptors appeared to be functionally absent. The beta-adrenergic receptor agonist response profile was abnormal in AY-32 cells. Norepinephrine produced a greater accumulation of cyclic AMP than epinephrine, and phenylephrine stimulated a much greater than normal response. Forskolin stimulation indicated an average level of adenylate cyclase activity in AY-32 cultures. Soluble preparations from AY-32 cells demonstrated a normal amount of cyclic AMP phosphodiesterase activity. AY-33 cells were comparable to normal urothelial cells in all respects save one. These tumorigenic cells had elevated levels of cyclic AMP phosphodiesterase activity. AY-34 cells, like AY-32 cells, were deficient in their responsiveness to prostaglandin E1. However, unlike the other tumorigenic lines, AY-34 cells had an excess of adenylate cyclase as demonstrated by their extraordinary responsiveness to forskolin. In addition, the accumulation of cyclic AMP in AY-34 cells in response to stimulation by epinephrine and norepinephrine, but not phenylephrine, was unusually great.(ABSTRACT TRUNCATED AT 400 WORDS)

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1977

Characterization of DNA used to assay sera for anti-DNA antibodies; determination of the specificities of anti-DNA antibodies in SLE and non-SLE rheumatic disease states.

Commercial 14C-labeled KB cell DNA, widely used to assay sera for anti-DNA antibodies, was chromatographed on benzoylated-naphthoylated-DEAE-cellulose (BNDC) and on hydroxyapatite (HAP). On BNDC, only 25% of the 14C label eluted with 1 M NaC1 (KB fraction I) characteristic of ds-DNA. Fifty-five percent of the label eluted with 50% formamide-1 M NaC1 (KB fraction II) characteristic of ss or denatured DNA. On HAP, however, none of the 14C label eluted with 0.2 M phosphate buffer as anticipated for ss-DNA, but, rather, all of the 14C label eluted with 0.4 M phosphate, characteristic of ds-DNA. after pretreatment with S1 endonuclease of Aspergillus oryzae, which selectively digests ss regions, however, 42% of the 14C label was lost from the 0.4 M phosphate peak. These results indicated that more than half of this 14C-KB-cell DNA preparation was ds-DNA with ss regions which was undetectable by HAP chromatography. 3H-ds-DNA and circular 3H-ss-DNA prepared from T7 and phiX174 bacteriophage, respectively, were found to be chromatographically pure on both BNDC and HAP. None of 10 non-SLE sera (rheumatoid arthritis 3, mixed connective tissue disease 4, scleroderma 1, ulcerative colitis 1, and pulmonary fibrosis with chronic active hepatitis 1), previously believed to contain anti-ds-DNA antibodies on the basis of KB cell DNA testing and detectable antibodies against KB fraction 1 or T7 DNA: all of 10 KB cell DNA positive SLE sera had antibodies against both. Additionally, none of the 10 non-SLE sera had antibodies against KB cell DNA when retested with DNA that had been pretreated with S1 endonuclease. Seven of these 10, however, as well as all 10 SLE sera, had antibodies against phiX174 DNA, KB fraction II DNA and alkali-denatured T7 DNA. The data support the conclusions that 1) false positive tests for anti-ds-DNA antibodies can result from contamination of ds-DNA with ds-DNA having ss regions, and 2) non-SLE sera do not contain antibodies specific for ds-DNA at levels comparable to those found in SLE sera but rather contain high levels of antibodies reacting with ss regions or mixed DNA.

Antibodies↗
PubMed1988

A rapid dot-blot assay to assess chimerism following sex-mismatched bone marrow transplantation.

Mixed chimerism may occur more frequently than previously thought following allogeneic bone marrow transplantation and may have implications in terms of relapse, graft-versus-host disease and immune reconstitution. DNA analysis using single or multilocus polymorphic probes cannot reliably discriminate between donor and recipient cells below a level of 10%. We used probe pHY2.1, a cloned segment of tandemly repeated DNA (2000 copies) on the long arm of chromosome Y. A dot blot procedure allowed us to immobilize DNA directly from 50 microliter of peripheral blood or bone marrow. Cross-reactivity was eliminated by hybridization at conditions of extreme stringency (65 degrees C, 50% formamide). Mixing experiments detected male DNA at a level of 0.1% after 10 h exposure. Five patients were studied serially post-bone marrow transplantation. One patient showed mixed chimerism for 12 months, one had complete autologous recovery and the remaining three showed complete engraftment. All results were verified by standard karyotyping on bone marrow cells. This technique is a simple, rapid and sensitive assay for chimerism following sex mismatched bone marrow transplantation.

Bone Marrow Transplantation↗
PubMed1988

The blue infarct: a simple method for the quantification of myocardial damage in the rat.

Evans blue dye was injected iv into rats 24 h before left coronary occlusion (CO) and the dye content extracted with formamide was estimated after various time intervals in the 1) right ventricle, 2) left ventricle above the ligature and 3) the rest of the left ventricle. There was no difference between portion 1 and 2 but portion 3 showed a progressive increase in dye content (2 to 3 fold) up to 24 h after CO. This result indicates that either the infarcted area possesses collateral circulation or a continuous blood backflow occurred. Dexamethasone (0.5 mg/kg) but not indomethacin (2 mg/kg) or BW755C (10 mg/kg) abolished extravasation of the dye.

Animals↗

Refine your search to explore more results.