Chromatographic methods for the analysis of basic neurotransmitters and their acidic metabolites

Chromatographic techniques for the determination of trace amounts of neurotransmitters were reviewed. The two techniques found to be most useful were GC-MS and the reversed-phase mode of HPLC with an electrochemical or fluorescent detector. For structure determination or unequivocal peak identification, GC-MS is the method of choice. In addition the limits of detection of GC-MS were better than those obtained by HPLC. However for routine analyses, HPLC is now being used in studies of mental illness and other diseases. Good resolution, reproducibility and sensitivity can be obtained without the derivatisation steps required for GC-MS, and catecholamines, serotonin, and their acidic metabolites can be concomitantly determined in one analysis.

Progesterone regulation of estradiol-induced rat uterine secretory protein, complement C3

Previously, using DNA sequencing, Northern and Southern analysis, and immunohistochemical data, we identified an estrogen-stimulated secretory protein as the third component of complement (C3). In this study, we demonstrate that progesterone modulated the estradiol regulation of C3 in immature rats as well as during the normal reproductive cycle. C3 was most abundant during estrus and reached its lowest concentration in diestrus. Immunoprecipitations reveal that progesterone prevented the estradiol-stimulated increase in radiolabeled C3 both in the media and tissue. The mechanism for the progesterone inhibition of estrogen-stimulated C3 appeared to be at the level of transcription or possibly mRNA stability since progesterone blocked the estradiol-stimulated increase in C3 mRNA.

[Determination of traces of gallium in air by oscillographic polarography]

Gallium and its compounds in air collected by millipore filter membrane are leached by 10% HNO3 at room temperature. After being adjusted with ammonia solution to pH8-9, the leachate is filtered and the filtrate is evaporated to dryness on a water bath. The residue is dissolved with 2 ml of 10% HNO3 and then into the solution are added 0.5 ml of 5% hydroxylamine hydrochloride solution, 0.20 ml of 5% sulfosalicyclic acid solution, 0.5 ml of NaF solution (1mg F/ml) and 1 drop of methyl red solution. Let it stand for 5 min after the color of the solution turns orange by addition of 1:1 NH4OH solution. Add 0.20ml of 0.20% cupferron solution, 0.20ml of 0.5% diphenyl-guanidine solution (prepared in 95% ethanol) and 0.5ml of acetic acid-ammonium acetate buffer (pH 7.0). Then add water to make the final volume of the test solution to be 10ml and measure the height of the second derivative polarographic wave at -1.08V (vs.SCE). The sensitivity of the method is 0.005-0.10 microgram/ml, the coefficient of variation 6.8%, recovery 97.8%. Within 0.005-0.10 microgram/ml, the wave height is linear with the concentration of gallium.

Estrogen regulation of tissue-specific expression of complement C3

The administration of estradiol to immature rats results in the increased synthesis and secretion of a 180-kDa protein, composed of 115- and 65-kDa subunits, by the uterine luminal epithelial cells. A monoclonal antibody against the 180-kDa protein was utilized to isolate the corresponding cDNA (LE-1) from a rat uterine luminal epithelial cell cDNA lambda gt11 expression library. This LE-1 cDNA was sequenced and shown to be homologous to complement component C3. The sequence was approximately 81 and 90% homologous to human and mouse C3, respectively. The LE-1 cDNA sequence was homologous with the 3' portion of the C3 mRNA containing the alpha subunit (115 kDa). Uterine mRNA isolated from immature rats treated with 1 microgram of estradiol for 24 h demonstrated a 25-fold increase in the concentration of a 6.0-kilobase mRNA by Northern hybridization with either LE-1 or authentic human C3 cDNA probes. To further examine the possibility that the estradiol-regulated secretory protein was C3, an aliquot of radiolabeled media protein from control and estradiol-stimulated rat uteri was incubated with goat anti-rat C3 antibody. The immunoprecipitated radiolabeled protein from estradiol-treated animals was increased significantly (p less than 0.01) compared to media from control animals. Analysis of the immunoprecipitated proteins on nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed a single protein of 180 kDa from estradiol-stimulated uterine media, whereas no detectable proteins were immunoprecipitated from media obtained from control uteri. Also, when the immunoprecipitated protein was reduced (20 mM dithiothreitol) it dissociated into two subunits of 115 and 65 kDa. Immunohistochemical studies demonstrated the presence of C3 only in the epithelial cells of estrogen-stimulated rat uteri. In addition, the estradiol-stimulated mRNA was only detectable in uterine epithelial cell RNA. Analysis of liver RNA demonstrated a 6.0-kilobase mRNA, as in the uterus, when hybridized with LE-1. However, unlike the uterus, its concentration was not influenced by estrogen administration with up to three daily injections of 100 micrograms of diethylstilbestrol. Based on biophysical, DNA sequence, and antibody data we conclude that rat uterine epithelial cells produce C3 in response to estradiol whereas the expression in the liver was not modulated by estrogens.

Epstein-Barr virus-activating principle in the ether extracts of soils collected from under plants which contain active diterpene esters

Soil samples were collected from the ground under the plants of Euphorbiaceae and Thymelaeaceae known to possess Epstein-Barr virus-activating diterpene esters. In a test system, the ether extracts of such soil samples at a concentration of 20 micrograms/ml induced Epstein-Barr virus early antigen in approximately 5-25% of the non-producer Raji cells. These findings suggest a possible interaction between plant-derived diterpene esters and the human system, and provide a new aspect in considering the cause of Epstein-Barr virus-associated diseases, particularly nasopharyngeal carcinoma.

Cytogenetic studies on an epithelial cell line derived from poorly differentiated nasopharyngeal carcinoma

An epithelial cell line, CNE-2, has been recently established from a poorly differentiated nasopharyngeal carcinoma, and it represents the first of its kind. Using chromosome banding techniques, cytogenetic analysis of the cell line was carried out. It was demonstrated that the chromosome numbers of the CNE-2 cells varied from 87 to 107 and the modal number was 104-103. All cells contained a series of structurally abnormal chromosomes, and most of them were either consistent or frequently found. Among these chromosomes there were two giant markers which, by banding pattern analysis, proved to be distinct from the so-called giant group A marker chromosomes previously found in many lymphoblastoid cell lines from NPC. Comparison between the CNE-2 and CNE, another epithelial cell line, which was established from well-differentiated squamous NPC, showed that while they were quite different in many cytogenetic aspects, they had three marker chromosomes in common, namely, an iso8q, a t(?;3q) and a small acrocentric one. The question of whether chromosome markers specific for NPC exist is discussed in the light of the data presented.

Development of an anticomplement immunoenzyme test for detection of EB virus nuclear antigen (EBNA) and antibody to EBNA

An anticomplement immunoenzyme test was developed by conjugating anti-human C3 antibody with horseradish peroxidase. EBNA could be detected by this test in all cell lines related to EB virus, as well as in nasopharyngeal carcinoma cells, but not in unrelated cell lines. Antibody to EBNA could also be detected. The test is sensitive and does not require a fluorescence microscope which makes it particularly suitable for mass survey.

Application of an immunoenzymatic method and an immunoautoradiographic method for a mass survey of nasopharyngeal carcinoma

The frequency of IgA antibody to virus capsid antigen (VCA) of EB virus was tested by an immunoenzymatic method among adults in a mass serological screening of the general population of 6 communes in South China, as a guide toward early detection of nasopharyngeal carcinoma. Sera from 56 patients already recognized as having nasopharyngeal carcinoma (NPC) also were tested. The screening was conducted with sera from 56,584 persons age 30 years and older in Zangwu County in the Guangsi Zhuang Autonomous Region. IgA antibody to VCA was found in 96% of the NPC patients tested; the geometric mean antibody titer for this group was 1:41. The antibody also was detected in 117 of the persons surveyed in the mass screening, and among these, the geometric mean antibody titer was 1:21. 20 of the antibody-positive persons were diagnosed by clinical and pathological examination as having NPC. 18 of these cases were diagnosed soon after the initial tests in June-September, 1978, and an additional 2 were diagnosed only after follow-up examinations 10 months after the first blood sample was taken. All of the persons who are in the antibody-positive group but exhibit no detectable tumors are to be reexamined periodically.