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Neutral {Fe(NO)2}9 dinitrosyliron complex (DNIC) [(SC6H4-o-NHCOPh)(Im)Fe(NO)2] (Im = imidazole): interconversion among the anionic/neutral {Fe(NO)2}9 DNICs and Roussin's red ester.

A neutral {Fe(NO)2}9 dinitrosyliron complex (DNIC) [(SC6H4-o-NHCOPh)(Im)Fe(NO)2] (Im = imidazole; 2) was prepared by the reaction of [Fe(mu-SC6H4-o-NHCOPh)(NO)2]2 (1) and 2 equiv of imidazole. In the synthesis of the anionic {Fe(NO)2}9 DNIC [(SC6H4-o-NHCOPh)2Fe(NO)2]- (3), thiolate [SC6H4-o-NHCOPh]- triggers ligand substitution of DNIC 2 to yield DNIC 3. At 298 K, complexes 2 and 3 exhibit well-resolved nine- and five-line electron paramagnetic resonance (EPR) signals at g = 2.031 and 2.029, respectively, the characteristic g value of DNICs. The facile interconversions among the neutral {Fe(NO)2}9 complex 2, the anionic {Fe(NO)2}9 complex 3, and Roussin's red ester 1 were demonstrated. The EPR spectrum (the pattern of hyperfine splitting) in combination with the IR nu(NO) (the relative position of the nu(NO) stretching frequencies) spectrum may serve as an efficient tool for the discrimination of the anionic {Fe(NO)2}9 DNICs, the neutral {Fe(NO)2}9 DNICs, and Roussin's red ester.

Electron Spin Resonance Spectroscopy↗

One-electron reduction of hepatic NADH-cytochrome b5 reductase as studied by pulse radiolysis.

The reduction of flavin in hepatic NADH-cytochrome b5 reductase by the hydrated electron (eaq-) was investigated by pulse radiolysis. The eaq- reduced the flavin of NADH-cytochrome b5 reductase to form the red semiquinone between pH 5 and 9. The spectrum of the red semiquinone differs from that of enzyme reduced by dithionite in the presence of NAD+. After the first phase of the reduction, conversion of the red to blue semiquinone was observed at acidic pH. Resulting products are the blue (neutral) or red (anionic) semiquinone or a mixture of the two forms. The pK value for this flavin radical was approximately 6.3. Subsequently, the semiquinone form reacted by dismutation to form the oxidized and the fully reduced forms of the enzyme with a rate constant of 1 x 10(3) M-1 s-1 at pH 7.1. In the presence of NAD+, eaq- reacted with NAD+ to yield NAD(.). Subsequently, NAD. transferred an electron to NAD+-bound oxidized enzyme to form the blue and red semiquinone or mixture of the two forms of the enzyme, where pK value of this flavin radical was approximately 6.3. The blue semiquinone obtained at acidic pH was found to convert to the red semiquinone with a first order rate constant of 90 s-1, where the rates were not affected by pH or the concentration of NAD+. The final product is NAD+-bound red semiquinone of the enzyme.

Animals↗

Fluorescent measurement of microalgal neutral lipids.

Nile Red, a dye that fluoresces at defined wavelengths depending upon the polarity of the surrounding medium, has been proposed to determine the neutral lipid content of microalgal cells. Herein we communicate modifications to this technique that facilitate its use as a high-throughput screening technology, as well as improving its accuracy and versatility.

Biotechnology↗

Histochemical techniques to localize rubber in guayule (Parthenium argentatum Gray).

There are few histochemical techniques for staining rubber in the cells of guayule. With regard to specificity, clarity and retention of the stain we found staining with oil red O or iodine-potassium iodide for bright field, and a combination of oil red O and dansyl chloride for epifluorescence microscopy to be the best methods. The plausible mechanisms of staining are discussed.

Azo Compounds↗

Sensitivity of picroindigocarmine/nuclear fast red (PIC/NF) stain for detection of spermatozoa: a serial dilution study of human ejaculate.

A serial dilution study from human ejaculate was done in order to assess the sensitivity of a commonly employed stain, picroindigocarmine/nuclear fast red, for the detection of spermatozoa. The results of the study indicate that spermatozoa may be detected readily at very low concentrations by scanning 20 high-power fields of a stained smear.

Female↗

HistoGreen: a new alternative to 3,3'-diaminobenzidine-tetrahydrochloride-dihydrate (DAB) as a peroxidase substrate in immunohistochemistry?

Abide its toxicity, 3,3'-diaminobenzidine-tetrahydrochloride-dihydrate (DAB) was the most potent marker for immunochemistry at the light and electron microscopic level in the last decades. Recently, a sensitive substrate for immunohistochemical staining methods and in-situ hybridization, HistoGreen, was developed for the use with peroxidase. In peroxidase reactions, HistoGreen delivers a green staining product which is suitable for permanent embedding without water. In contrast to DAB, HistoGreen is not toxic. To evaluate its usefulness, we performed comparative immunohistochemistry on angiotensin II (AT1)-receptors with DAB- and HistoGreen-staining on paraffin embedded slices of the rat brain at the light microscopic level. This also included counterstaining with Mayer's Hemalum and Nuclear Fast Red, respectively. We could demonstrate that HistoGreen delivers a coarsely grained label which is fast detectable in light microscopy. HistoGreen equals DAB in the exact localization of the immunoreaction to a large degree but its reaction product is considerably less stable in alcohol and water than DAB. In combination with Nuclear Fast Red, HistoGreen provides excellent imaging properties for the visualization and documentation of immunoreactive structures paired with an adequate demonstration of cellular details. Its tendency towards rapid over-staining as well as its low stability will restrict the use of HistoGreen in some areas of immunohistochemical research, yet the new chromogen represents an interesting alternative to DAB at the light microscopic level.

3,3'-Diaminobenzidine↗

[Serologic evaluation of the molecular forms of choriogonin during the course of pregnancy].

Antigenous (antibody binding) activity in vitro and disaggregating (absolute and relative) activity of choriogonin in the urine were studied simultaneously during pregnancy by means of the serologic tests--antibody neutralization and red cell disaggregation. The time course of choriogonin activity in the urine, which reflects variations in the molecular parameters of choriogonin in pregnancy indicates that it may be detected in the urine in the form of isohormones. Variations in the molecular parameters of choriogonin during pregnancy differ from those in its antibody binding activity. Application of serodiagnostic approaches may be valuable in determining the time course of the molecular parameters of hormones.

Chorionic Gonadotropin↗

Catecholamine-stimulated ion transport in duck red cells. Gradient effects in electrically neutral [Na + K + 2Cl] Co-transport.

The transient increase in cation permeability observed in duck red cells incubated with norepinephrine has been shown to be a linked, bidirectional, co-transport of sodium plus potassium. This pathway, sensitive to loop diuretics such as furosemide, was found to have a [Na + K] stoichiometry of 1:1 under all conditions tested. Net sodium efflux was inhibited by increasing external potassium, and net potassium efflux was inhibited by increasing external sodium. Thus, the movement of either cation is coupled to, and can be driven by, the gradient of its co-ion. There is no evidence of trans stimulation of co-transport by either cation. The system also has a specific anion requirement satisfied only by chloride or bromide. Shifting the membrane potential by varying either external chloride (at constant internal chloride) or external potassium (at constant internal potassium in the presence of valinomycin and DIDs [4,4'-diisothiocyano-2,2'-disulfonic acid stilbene]), has no effect on nor-epinephrine-stimulated net sodium transport. Thus, this co-transport system is unaffected by membrane potential and is therefore electrically neutral. Finally, under the latter conditions-when Em was held constant near EK and chloride was not at equilibrium-net sodium extrusion against a substantial electrochemical gradient could be produced by lowering external chloride at high internal concentrations, thereby demonstrating that the anion gradient can also drive co-transport. We conclude, therefore, that chloride participates directly in the co-transport of [Na + K + 2Cl].

Animals↗

3D confocal reconstruction of gene expression in mouse.

Three-dimensional computer reconstructions of gene expression data will become a valuable tool in biomedical research in the near future. However, at present the process of converting in situ expression data into 3D models is a highly specialized and time-consuming procedure. Here we present a method which allows rapid reconstruction of whole-mount in situ data from mouse embryos. Mid-gestation embryos were stained with the alkaline phosphotase substrate Fast Red, which can be detected using confocal laser scanning microscopy (CLSM), and cut into 70 microm sections. Each section was then scanned and digitally reconstructed. Using this method it took two days to section, digitize and reconstruct the full expression pattern of Shh in an E9.5 embryo (a 3D model of this embryo can be seen at genex.hgu.mrc.ac.uk). Additionally we demonstrate that this technique allows gene expression to be studied at the single cell level in intact tissue.

Alkaline Phosphatase↗

Novel findings in inhibition of mast cell-dependent immediate-type cutaneous reactions by Gahmi-Shini-San.

This report describes an inhibitory effect of Gahmi-Shini-San (GSS) on mast cell-mediated immediate-type allergic reactions. GSS is an Oriental herbal medication, which has been successfully used in Korea for the treatment of allergic disorders, mainly skin anaphylactic diseases. GSS inhibited the ear swelling response induced by intradermal injection of compound 48/80 in a mouse model on a concentration-dependent basis. The mast cells in mouse ear tissue were stained by alcian blue/nuclear fast red. GSS significantly inhibited the compound 48/80-induced degranulation from mast cells in ear tissue. GSS dose-dependently inhibited the histamine release from the rat peritoneal mast cells by compound 48/80. We also studied the effect of GSS on mast cell-dependent passive cutaneous anaphylaxis activated by dinitrophenyl IgE antibody. GSS showed inhibition of passive cutaneous anaphylaxis following oral administration. These results indicated that GSS has inhibitory effect on mast cell-dependent immediate type cutaneous reactions.

Alcian Blue↗

Photosensitized destruction of Chlorella vulgaris by Methylene Blue or Nuclear Fast Red combined with hydrogen peroxide under visible light irradiation.

A considerable number of investigations have started to elucidate the essential roles biological agents play in the biodeterioration of stone. Chemical biocides are becoming increasingly banned because of the environmental and health hazards associated with these toxic substances. The present study reports the photodynamic effect of Methylene Blue (MB) and Nuclear Fast Red (NFR) in the presence of hydrogen peroxide (H2O2) on the destruction of the algae Chlorella vulgaris (C. vulgaris) under irradiation with visible light. Illumination of C. vulgaris in the presence of MB or NFR combined with H2O2 results in the decomposition of both the algal species and the photosensitizer. The photodynamic effect was investigated under aerobic and anaerobic conditions. Differences in mechanism type are reported and are dependent on both the presence and the absence of oxygen. The behavior of each photosensitizer leads to a Type II mechanism and a Type I/Type II combination for MB and NFR, respectively, being concluded. This novel combination could be effective for the remediation of biofilm-colonized stone surfaces.

Chlorella vulgaris↗

Isolation and characterization of an arildone-resistant poliovirus 2 mutant with an altered capsid protein VP1.

Arildone (4-[6-(2-chloro-4-methoxyphenoxy)hexyl] -3,5-heptanedione is a selective inhibitor of poliovirus uncoating. We have isolated an arildone-resistant poliovirus 2 variant and characterized it. In single cycle growth curve experiments the resistant virus was not influenced by 1 microgram/ml of arildone, which completely inhibited the replication of the sensitive virus. In neutralization experiments the rates of inactivation vs time of the parent and the resistant virus proved indistinguishable. The adsorption behavior of the mutant closely resembled that of the wild-type. Uncoating as measured with neutral red-sensitized arildone-resistant mutant virus was unaffected by arildone, in contrast to the uncoating of the sensitive parent virus. It has been previously shown that arildone stabilizes the poliovirus capsid from alkaline degradation. The arildone-resistant mutant, however, was not markedly stabilized by the drug under these conditions. No difference in thermostability between mutant and parent virus could be detected. In isoelectric focusing the sensitive virus exhibited 2 peaks, but in the presence of arildone only one peak was apparent. In contrast, the arildone-resistant virus remained unaffected by the presence of arildone. Analysis of the capsid proteins of the sensitive parent and the resistant virus in SDS-polyacrylamide gels revealed no difference in the patterns; however, peptide mapping showed clear differences in VP1.

Animals↗

Combined immunocytochemistry and fluorescence in situ hybridization for simultaneous tricolor detection of cell cycle, genomic, and phenotypic parameters of tumor cells.

We describe the development and application of a sensitive high-resolution fluorescence alkaline phosphatase (APase)-Fast Red immunocytochemical (ICC) staining method in combination with fluorescence in situ hybridization (ISH) and bromodeoxyuridine (BrdU) detection. The high fluorescence intensity, accurate localization, and advantageous slow-fading properties make the APase-Fast Red reaction a valuable tool for detection of antigens or specific DNA probes in biological cell preparations. Since the enzyme precipitate proved to be resistant to enzymatic pre-treatment steps and stable during the entire ISH procedure, APase-Fast Red immunostaining could be combined with subsequent visualization of DNA target sequences by fluorescence ISH. The lung cancer cell lines NCI-H82 and EPLC 65 were used as a model system for simultaneous detection of cell proteins, such as the neural cell adhesion molecule (N-CAM), cytokeratin filaments, lamin or the Ki67 antigen (Ki67-Ag), and centromere-specific DNA probes for human chromosomes 1, 7, or 17. In addition, the combined ICC/ISH procedure could be extended with the immunodetection of BrdU incorporated by tumor cells in S-phase. As a consequence, a combined ICC/ISH/BrdU detection procedure is now available that enables analysis of relatively complex tumor populations on the basis of different ICC and genetic markers as well as proliferative activity.

Alkaline Phosphatase↗

Toluidine red unheated serum test, a nontreponemal test for syphilis.

We have shown that a modification of the color-coded antigen developed by Kasatiya and Lambert (Appl. Microbiol. 28:317-318, 1974) can be used as a substitute for other nontreponemal antigens used in screening tests for syphilis. The antigen is based on the Venereal Disease Research Laboratory antigen, with EDTA, choline chloride, and toluidine red toner added. Performance of the toluidine red unheated serum test (TRUST) is identical to that of the rapid plasma reagin 18-mm circle card test (U.S. Department of Health, Education, and Welfare, Public Health Service Publication no. 411). In a series of preliminary evaluations, the TRUST antigen was found to be stable over a period of 6 months at 4 degrees C. In a comparison of TRUST with the rapid plasma reagin card test, the qualitative agreement was 100%, whereas agreement between these two tests and the Venereal Disease Research Laboratory slide test was 99.7%. The quantitative agreement +/- 1 twofold dilution between TRUST and the rapid plasma reagin card test was 100%; between TRUST and the Venereal Disease Research Laboratory slide test it was 75.0%; and between the rapid plasma reagin card and Venereal Disease Research Laboratory slide tests it was 60.0%.

Edetic Acid↗

Identification of spermatozoa and round spermatids in the ejaculates of men with spermatogenic failure.

OBJECTIVES: As many as 10% of infertile men have azoospermia caused by spermatogenic failure or ductal obstruction. The histologic diagnoses associated with spermatogenic failure--Sertoli cell-only syndrome, maturation arrest, and hypospermatogenesis--do not necessarily represent global changes in the affected testis, as occasional seminiferous tubules may still produce mature germ cells. Intracytoplasmic sperm injection (ICSI) allows individual sperm that have been isolated from testicular tissue to fertilize oocytes. This study assessed whether mature germ cells (either round spermatids or spermatozoa) were present in the ejaculates of patients with spermatogenic failure. METHODS: All semen analyses performed at our tertiary care institution from January 1993 through December 1995 were reviewed to identify azoospermic men with spermatogenic failure. During this period, our laboratory employed Nuclear-Fast Red and picroindigocarmine staining (NF-PICS) of cytospin slides to identify rare spermatozoa and spermatids in otherwise azoospermic ejaculates. RESULTS: Of 3005 analyses reviewed, 20 azoospermic men whose infertility was solely attributable to spermatogenic failure were identified. The histologic diagnoses were germinal cell aplasia (n = 7), complete maturation arrest (n = 6), incomplete maturation arrest (n = 3), and hypospermatogenesis (n = 4). Using the NF-PICS technique, mature germ cells were identified in the ejaculates of 15 men (75%), and 9 men (45%) had fully formed spermatozoa present. CONCLUSIONS: In the clinical management of azoospermic infertile men, the NF-PICS technique may be used to identify men who have some degree of testicular spermatogenesis. This might obviate the need for the purely diagnostic testis biopsy that is performed before therapeutic biopsy for testicular sperm extraction in conjunction with ICSI.

Biopsy↗

Effect of polyethylenimine, a cell permeabilizer, on the photosensitized destruction of algae by methylene blue and nuclear fast red.

The present study reports the effect a cell permeabilizer, polyethylenimine (PEI) has on the photodynamic effect of methylene blue (MB) and nuclear fast red (NFR) in the presence of hydrogen peroxide (H2O2). The photosensitized destruction of the algae Chlorella vulgaris under irradiation with visible light is examined. The photodynamic effect was investigated under aerobic and anaerobic conditions. The presence of a permeabilizer during the photosensitized destruction of C. vulgaris does not enhance the activity of the MB, MB/H2O2 system or the NFR, NFR/H2O2 system under aerobic conditions. However under anaerobic conditions we have determined that when a cell permeabilizer was added to the MB/H202 system, the photosensitized destruction of C. vulgaris proceeded via a combination of Type I and Type II mechanisms. The presence of PEI enforces MB/H2O2 to be active toward the destruction of C. vulgaris whether oxygen is present or absent. Under aerobic and anaerobic conditions the activity of NFR was suppressed in the presence of PEI as a result of electrostatic interactions between the photosensitizer and the cell permeabilizer. The decrease in fluorescence recorded is indicative of destruction of the chlorophyll a pigment.

Cell Membrane Permeability↗

[Pure red blood cell aplasia associated with neutralizing antibodies against erythropoietin induced by epoetin alfa:a new form of acquired erythroblastopenia in auremic patients].

We report the case of a woman with end-stage renal disease on maintenance hemodialysis and treated with recombinant human erythropoietin (epoetin alfa) administered subcutaneously, who developed a pure red cell aplasia secondary to the development of neutralizing antibodies anti-erythropoietin after 8 months of treatment. Despite epoetin withdrawal and immunosuppressive treatment with corticosteroids and gammaglobulins the patient still has high red blood cell transfusion requirements and undetectable plasma erythropoietin levels. Pure red cell aplasia secondary to the development of neutralizing antibodies anti-erythropoietin is a rare but severe complication associated with the use of recombinant human erythropoietin in uremic patients. In recent years, the incidence of this complication has sharply increased, specially associated with the use of epoetin alfa administered subcutaneously. For this reason, the Spanish Drug Agency has recently contraindicated treating uremic patients with epoetin alfa administered subcutaneously.

Adult↗