Detection of IgG and IgM antibodies with ELISA technique in human trichomoniasis

The direct wet mount examination of vaginal secretion, widely applied for the diagnosis of Trichomonas vaginalis infection in woman patients, is rapid and economical, however, the sensitivity of this technique is not so high. In this study enzyme-linked immunosorbent assay (ELISA) was employed for the detection of serum anti-T. vaginalis IgG and IgM antibodies from 30 vaginal trichomoniasis patients and 30 non-infected healthy persons. The results were as follows: 1. Serum ELISA-IgG value was 0.37 +/- 0.134 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.21 +/- 0.054 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgG antibody were 70.0% and 96.7%, respectively. 2. Serum ELISA-IgM value was 0.33 +/- 0.177 (Mean +/- S.D.) in vaginal trichomoniasis patients and 0.11 +/- 0.051 in healthy controls (p less than 0.005), and the sensitivity and specificity of ELISA for serum IgM antibody were 70.0% and 96.7%, respectively. 3. The ELISA-IgG values showed a significant correlation with ELISA-IgM values (r = 0.77, p less than 0.005). With above results, it is assumed that ELISA is a reliable method for the diagnosis of T. vaginalis infection and simultaneous measurement of serum IgG and IgM with this technique is recommended.     

Arachidonic acid mobilization and phosphoinositide turnover by the terminal complement complex, C5b-9, in rat oligodendrocyte x C6 glioma cell hybrids

Previously, we have shown that rat oligodendrocytes release phospholipid and generate arachidonic acid (AA) and leukotriene B4 in response to sublytic C5b-9 formation. In the present study, we investigated the biochemical pathways by which C5b-9 generates AA from clone ROC-1, a fusion product of rat oligodendrocytes and C6 glioma. Cells were incubated for 24 h in the presence of [3H]AA or [3H]myoinositol. They were then sensitized with antibody against hybrid cell stroma and treated for 1 h with C9-depleted human serum (C9D-HS) or C9D-HS reconstituted with C9. Alternatively, cells were treated with C8,C9D-HS or C8,C9D-HS reconstituted with C8 or C8 plus C9 for 1 h. Qualitative and quantitative analysis of the released [3H]AA and [3H]myoinositol radiolabeled products were performed by thin layer chromatography/autoradiography and anion exchange chromatography, respectively. The major [3H]AA radiolabeled products after C5b-9 stimulation comigrated with intact phospholipid and AA standards, and the major [3H]myoinositol radiolabeled product was inositol-1-phosphate. Treatment of cells with phospholipase A2 inhibitors, mepacrine and bromophenacyl bromide, abolished AA release by C5b-9. In the absence of extracellular Ca2+, C5b-9 also failed to induce the release of AA. Interestingly, 1-(5-isoquinolinsulfonyl)-2-methylpiperazine (H-7), a potent inhibitor of protein kinases, inhibited AA release by C5b-9, whereas AA release stimulated by the calcium ionophore A23187 was not blocked by H-7. The results suggest that AA generation by C5b-9 from the ROC-1 clone involves activation of Ca2+-dependent phospholipase A2 which is regulated by protein kinase-dependent mechanisms.     

Light Activation of Pyruvate, Orthophosphate Dikinase in Maize Mesophyll Chloroplasts: A Role for Adenylate Energy Charge

Pyruvate, orthophosphate dikinase (EC 2.7.9.1 [EC] ) was activatedin the light and inactivated following a dark treatment in intactmaize mesophyll chloroplasts. Addition of catalase (100–250units/ml) to the assay medium was necessary to obtain good activationand to keep the enzyme in an active state during illumination.Arsenate and carbonyl cyanide m-chlorophenyl-hydrazone, uncouplersof photophosphorylation, inhibited the activation. Pyruvate,which has been proposed to have a critical role in supportingthe light activation of pyruvate, orthophosphate dikinase, actuallyinhibited the activation. The pyruvate level in the chloroplastsuspension decreased when the enzyme was light-activated. Measurementsof adenylates and pyruvate in the chloroplasts indicated thatthe energy state of the chloroplasts was more important forthe light activation than was the level of pyruvate. ¹Present address: Department of Biochemistry, Faculty of Science,Saitama University, 255, Shimo-Okubo, Urawa, 338 Japan ²Present address: National Institute of Agrobiological Resources,Yatabe, Tsukuba, Ibaraki, 305 Japan (Received May 2, 1989; Accepted October 2, 1989)     

Phosphatidylethanolamine synthesis by castor bean endosperm : membrane bilayer distribution of phosphatidylethanolamine synthesized by the ethanolaminephosphotransferase and ethanolamine exchange reactions

A base exchange reaction for synthesis of phosphatidylethanolamine by the endoplasmic reticulum of castor bean (Ricinus comminus L. var Hale) endosperm has been examined. The calculated Michaelis-Menten constant of the enzyme for ethanolamine was 5 micromolar and the optimal pH was 7.8 in the presence of 2 millimolar CaCl₂. l-Serine, N-methylethanolamine and N,N-dimethylethanolamine all reduced ethanolamine incorporation, while d-serine and myo-inositol had little effect. These inhibitions of ethanolamine incorporation were found to be noncompetitive and ethanolamine also noncompetitively inhibited l-serine incorporation by exchange. The activity of the ethanolamine base exchange enzyme was affected by several detergents, with the best activity being obtained with the zwitterionic defjtergent 3-3-cholamidopropyl) dimethylammonio-2-hydroxyl-1-propanesulfonate.     

Redox titrations of carbon monoxide dehydrogenase from Clostridium thermoaceticum.

Redox titrations of carbon monoxide dehydrogenase (CODH) from Clostridium thermoaceticum were performed using the reductant CO and the oxidant thionin. Titrations were followed at 420 nm, a wavelength sensitive to redox changes of the iron-sulfur clusters in the enzyme. When CODH was oxidized by just enough thionin to maximize A420, two molecules of CO per mole of CODH dimer (4 equiv/mol) reduced the enzyme fully. Likewise, 4 equiv/mol of thionin oxidized the fully-reduced enzyme to the point where A420 maximized. The four n = 1 redox sites which titrated in this region were designated group I sites. They include at least two iron-sulfur clusters, [Fe/S]A and [Fe/S]B, and two other sites, A' and B'. The [Fe4S4]2+/1+ cluster in CODH is included in this group. [Fe/S]B and B' have reduction potentials (at pH 8) below -480 mV vs NHE; [Fe/S]A and A' have reduction potentials above that value. The reduction potential of either [Fe/S]B or B' is near to the CO/CO2 couple at pH 8 (-622 mV). When CODH was oxidized by more than enough thionin to maximize A420, some of the excess thionin oxidized the so-called group II redox sites. These sites have reduction potentials more positive than group I and do not exhibit changes at 420 nm when titrated. Titration of group II sites required 1-2 equiv/mol. EPR of reduced group II sites exhibited the gav = 1.82 signal. When these sites were oxidized, the only signal present had g values at 2.075, 2.036, and 1.983.(ABSTRACT TRUNCATED AT 250 WORDS)     

Computational sequence analysis of matrix metalloproteinases

Matrix metalloproteinases (MMP) play a cardinal role in the breakdown of extracellular matrix involved in a variety of biological and pathological processes. Research on MMPs has classified and characterized these enzymes according to their matrix substrate specificity, gene and protein domain structure, and regulation of activity and expression. However, the discovery of new MMPs has introduced a need for a more comprehensive and systematic method of classification and quantitative comparison of known and newly discovered members. This study compiles a sequence alignment, constructs a dendrogram, and calculates physical data and homology percentage assignments in order to obtain further insight into MMP structure-function relationships. Thorough analysis of MMP primary sequence domains, physical data patterns, and statistical analysis of sequence homology yields higher resolution in the similarities and differences that group MMP members.     

Production of a polysaccharide, methylan, in Methylobacterium organophilum by controlling ammonium ion

Summary Cell growth increased proportionally to the initial concentration of ammonium ion, however, methylan production was significantly inhibited at the high concentration of ammonium ion. The control of ammonium ion within the desired level(usually 0.45 g/l) was needed to reduce the inhibition. Methylan production was increased to 12.5 g/l by maintaining ammonium ion below 0.15 g/l.     

Synthesis of biodegradable emulsifier using lipase in anhydrous pyridine

Summary Synthesis of a bioemulsifier using a lipase from Pseudomonas sp. with fructose and vinyl laurate was carried out in anhydrous pyridine. The synthetic product was identified as laurylfructose with an emulsifying activity on various hydrocarbons, edible oils and petroleum oils. The compound reduced the surface tension of distilled water from 72 mN/m to 29 mN/m and the interfacial tension of water/n-hexadecane from 50 mN/m to 6 mN/m.