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At least 487 records · Page 27Linked to original sources
PubMed1976

Beta-adrenergic receptors in rat myocardium: direct detection by a new fluorescent beta-blocker.

A new fluorescent beta-blocker, 9-amino-acridin propranolol (9-AAP), was administered i.v. to rats. Multiple fluorescent 9-AAP binding sites were observed on cardiac muscle cells in frozen sections. Intensity and density of cardiac 9-AAP fluorescence were markedly reduced following pretreatment with (+/-)- and (-)-propranolol but not with (+)-propranolol. Our findings suggest that 9-AAP may label beta-adrenergic receptor sites in rat myocardium.

Acridines↗
PubMed1993

Evaluation of a rapid latex test for direct detection of Streptococcus agalactiae in various obstetrical and gynaecological disorders.

Cervical samples collected during speculum examination in 413 women were tested for the presence of Streptococcus agalactiae by Gram staining, a new latex agglutination test and standard cultures. The results of each method are reported in correlation with the clinical circumstances of isolation. Gram stain and the latex agglutination test had a sensitivity of 30% and 78%, and a specificity of 89% and 98% respectively compared with culture. The sensitivity of the latex agglutination test was higher in cases of premature rupture of membranes (90%), presumed chorioamnionitis (86%), presumed post-partum endometritis (86%) and presumed salpingitis (87%). This latex agglutination test appears to be useful for identifying patients who are heavily colonized with Streptococcus agalactiae and are at a high risk of infection.

Evaluation Studies as Topic↗
PubMed1999

A PCR-ELISA Method for Direct Detection of the Oyster Pathogen Haplosporidium nelsoni.

: A rapid method, utilizing both polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA), was developed for detection of oyster MSX disease. The technique included using Haplosporidium nelsoni pathogen-specific PCR primers (based on ribosomal RNA genes), a Chelex resin (for rapid DNA extraction from oyster mantle tissues), and cloned H. nelsoni rRNA plasmid DNA (for use as a capture probe). Digoxigenin was incorporated into the pathogen-specific PCR products, which were captured by the coated probe in a fast hybridization reaction and then detected by ELISA. The sensitivity of PCR amplification on cloned plasmid DNA was 10 fg for detection by stained agarose gel, and increased to 0.01 fg for ELISA. Positive signals were observed in infected oysters using the PCR-ELISA technique. This method may be applicable to early detection of infection.

Journal Article↗
PubMed2006

Direct detection of nitric oxide in human blood serum by use of 1,3,5,7-tetramethyl-8-(3',4'-diaminophenyl)difluoroboradiaza-s-indacene with HPLC.

To study the relationship between amounts of nitric oxide (NO) in blood and the development of ischemic cardio-cerebrovascular diseases, trace NO in human blood serum has, for the first time, been determined by use of a 1,3,5,7-tetramethyl-8-(3',4'-diaminophenyl)difluoroboradiaza-s-indacene (TMDABODIPY)-based HPLC method. The proposed method is simple, rapid, and efficient, owing to its high sensitivity and good selectivity for NO. TMDABODIPY and its NO derivative are separated to baseline in 4 min, with simple separation conditions, on a C(18) column eluted with 50 mmol L(-1) ethanolamine in methanol. The derivative is detected by fluorescence at an emission wavelength of 507 nm with excitation at 498 nm. The response is a linear function of concentration in the range 0.8-800 nmol L(-1) NO. The detection limit can reach 2 x 10(-11) mol L(-1) (signal-to-noise ratio=3). The method has been used to detect NO in the serum of patients with five kinds of ischemic cardio-cerebrovascular disease and two diseases closely connected with ischemic cardio-cerebrovascular diseases. Recoveries of NO from spiked serum samples were between 96.58 and 105.71% and concentrations of NO observed in real samples were at 10(-7) mol L(-1) levels. Our studies indicate that the proposed TMDABODIPY-based HPLC technique can be developed into a sensitive and new method for clinical assay and pathology research.

Aza Compounds↗
PubMed2004

Indirect immunofluorescence microscopy for direct detection of Xylella fastidiosa in xylem sap.

The plant pathogen Xylella fastidiosa is the causative agent of a number of diseases of economically important crops, including Pierce's disease that affects grapevines. Using a commercially available antibody specific for X. fastidiosa, we have established a protocol for microscopic identification of the bacterium by indirect immunofluorescence. This antibody clearly labels an uncharacterized antigen concentrated at a single pole of X. fastidiosa cells, but does not react with a non- Xylella control. This technique was also performed successfully on xylem exudates from several different plant genera and correlated well with standard enzyme-linked immunosorbent assay tests. These results establish a novel method for in situ assessment of X. fastidiosa infection from host plants.

Asteraceae↗
PubMed1995

An early transient increase of intracellular Na+ may be one of the first components of the mitogenic signal. Direct detection by 23Na-NMR spectroscopy in quiescent 3T3 mouse fibroblasts stimulated by growth factors.

23Na-NMR spectroscopy was designed to allow for continuous recording of intracellular Na+ in 3T3 fibroblasts stimulated by serum growth-factors in the presence of ion transport inhibitors. The metabolic state of cells at rest and following stimulation was monitored by 31P-NMR spectra of ATP and related high-energy phosphates. The study demonstrates that early activation of ion transporters by addition of serum is marked by the appearance of transient increase of the intracellular Na+, beginning 3 min after addition of serum to quiescent culture and lasting approx. 20 min. The initial rise in cellular Na+ results from an increased activity of the bumetanide-sensitive Na+/K+/Cl- cotransport and of the amiloride-sensitive Na+/H+ antiport. It is suppressed by any one of these inhibitors. Subsequent activation of the ouabain-sensitive Na+/K(+)-ATPase results in an increased Na+ efflux, leading to a return of intracellular Na+ to its initial baseline. Previous work had shown that the early activation of bumetanide-sensitive and amiloride sensitive ion-transporters by growth-factors was essential for induction of cell division, at least in some cell types. Preventing ion activation by adding ion-transport inhibitors lead to the inhibition of DNA synthesis 18 h later. This process was reversible upon elimination of these inhibitors. Even though alternative non-specific effects of these inhibitors cannot be ruled out, the observed transient peak in intracellular Na+ may be one of the earliest components of the mitogenic signal. On the basis of previous works, its effect seems to be related to the activation of Ca(2+)-dependent and cyclic AMP second messenger pathways. The different mechanisms whereby the activated Na+/K+/Cl- cotransport and the Na+/H+ antiport contribute to this signal need to be further investigated.

3T3 Cells↗
PubMed1988

Monoclonal antibody directed detection of cytochrome P-450 (PCN) in human fetal liver.

Monoclonal antibodies (MAbs) raised to rat liver cytochrome P-450s induced by phenobarbital, 3-methylcholanthrene, and pregnenolone-16 alpha-carbonitrile were used to detect these epitope specific P-450s in human abortion fetuses 14-24 weeks of age. This was performed using a Western blot technique. In parallel, ECOD was determined in the same tissue specimens. Of seven different MAbs used MAb PCN 2-13-1/C2 was the only one that immunodetected a cytochrome P-450 band with Western blot analyses of human fetal liver microsomes. This band was consistently detected in all fetal liver specimens studied although the intensity varied among samples. No bands were detected in microsomal preparations from adrenal and renal tissues obtained from the same fetuses. The human adult liver microsomal specimens also contained a MAb PCN 2-13-1/C2 identified cytochrome P-450 band. ECOD activity was detected in all but one of the human fetal livers and varied between 0.22 and 47.5 pmol min-1 mg protein-1, as compared to 113 to 489 pmol min-1 mg protein-1 in human adult livers. In all of the fetuses except one the adrenal ECOD activity (0.63-37.0 pmol min-1 mg protein-1) exceeded that in the liver. The renal ECOD activities were, however, low. The hepatic and adrenal ECOD activities correlated with each other (r = 0.95). Although the ECOD activity is a function of several different P-450s there was also a correlation (r = 0.78) between the ECOD activity and the MAb immunodetected protein band intensity in Western blots of human fetal liver microsomes. The presence of a MAb PCN 2-13-1/C2 identified band in fetal liver microsomes may be indicative of a steroid-dependent effect in fetal life.

7-Alkoxycoumarin O-Dealkylase↗