MHPG and heart rate as correlates of nonresponse to drug therapy in panic disorder patients

Little is known about biological predictors of treatment response in panic disorder (PD). In the present study heart rate, blood pressure, plasma cortisol and plasma MHPG were investigated at baseline in a sample of 44 PD patients as possible predictors for nonresponse to treatment. We used a strict definition of nonresponse to find patients who did not respond at all after 12 weeks of treatment with brofaromine or fluvoxamine. Patients were considered nonresponders when they fulfilled two criteria: they did not show a 50% reduction of agoraphobic avoidance and they still experienced panic attacks at endpoint. The variables that differed significantly between the groups were used to predict nonresponse to drug therapy. Using this strict definition of nonresponse, 15 patients (32.6%) were considered nonresponders. These patients were characterised by a higher plasma MHPG concentration and a higher heart rate at baseline. These variables were subsequently used to predict nonresponse.     

Improved rat liver preservation by hypothermic continuous machine perfusion using polysol, a new, enriched preservation solution.

For experimental machine perfusion (MP) of the liver, the modified University of Wisconsin solution (UW-G) is most often used. In our search for an enriched MP preservation solution, Polysol was developed. Polysol is enriched with various amino acids, vitamins, and other nutrients for the liver metabolism. The aim of this study was to compare Polysol with UW-G for MP preservation of the liver. Rat livers were preserved during 24 hours with hypothermic MP using UW-G (n = 5) or Polysol (n = 5). Hepatocellular damage (aspartate aminotransferase [AST], alanine aminotransferase [ALT], lactate dehydrogenase [LDH], alpha-glutathione-S-transferase [alpha-GST]) and bile production were measured during 60 minutes of reperfusion (37 degrees C) with Krebs-Henseleit buffer. Control livers were reperfused after 24 hours of cold storage in UW (n = 5). MP using UW-G or Polysol showed less liver damage when compared with controls. Livers machine perfused with Polysol showed less enzyme release when compared to UW-G. Bile production was higher after MP using either UW-G or Polysol compared with controls. In conclusion, machine perfusion using Polysol results in better quality liver preservation than cold storage with UW and machine perfusion using UW-G.     

In vitro studies of antiphospholipid antibodies and its cofactor, beta 2-glycoprotein I, show negligible effects on endothelial cell mediated protein C activation.

The effect of sera and purified IgG isolated from plasma of 46 patients with systemic lupus erythematosus (SLE) and 9 healthy donors on the endothelial cell (EC) mediated protein C activation was investigated. Out of the 46 SLE sera used, 19 were antiphospholipid antibodies (aPL) positive. From 12 patients IgG was isolated, of which 6 contained aPL. EC were first incubated with IgG (7 mg/ml) or serum (1:1 diluted) for 1 h and then tested for their ability to promote protein C activation by thrombin, with the cells either in a monolayer or in a suspension. The normal range (mean of control values +/- 2 SD) of protein C activation was 80-120%. In contrast to others, we could not detect an inhibition of protein C activation by any of the patient IgG's or sera. The recently described cofactor for binding of antiphospholipid antibodies to phospholipids, beta 2-glycoprotein I, was purified and added to the purified IgG's. A combination of these two components did not inhibit the EC mediated protein C activation by thrombin. This study suggests that the inhibition of the protein C activation, mediated by EC, is not a general mechanism by which aPL related thrombosis can be explained.     

Maternal-Fetal Immune Relationship: Another Point of View

Placental transfer of maternal IgG is known to be an active process resulting in a concentration on the fetal side of the circulation--at the apparent expense of that in the mother--at full term. However, when this apparent decrease in maternal IgG is related to the actual hemodilution occurring in parallel, the total inventory of the mother's IgG appears to be constant throughout pregnancy. Therefore, conclusions regarding the variations in IgG concentrations cannot be drawn without simultaneous information about plasma volume fluctuations.     

Functional characterization of muscarinic receptors in murine airways.

1. The effects of muscarinic receptor antagonists considered to be selective for M1 receptors (pirenzepine; PZ), M2 receptors (AFDX-116), and for M3 receptors (4-diphenyl acetoxy N-methyl-piperidine (4-DAMP)) were used to investigate the existence of muscarinic receptors subtypes in murine airways. Atropine was used as a nonselective antagonist. The effects of these antagonists were studied upon tracheal contractions induced either by EFS (electric field stimulation) or by application of an exogenous cholinoceptor agonist (arecoline). 2. The muscarinic receptor antagonists tested inhibited arecoline-induced tracheal contractions with the following rank order of potency: 4-DAMP = atropine > pirenzepine = AFDX-116. The rank order of potency of the muscarinic antagonists used in inhibiting EFS-induced tracheal contractions was: 4-DAMP = atropine > PZ > AFDX-116. The pA2 values for these antagonists were similar when compared to the pA2 values determined in guinea-pig and bovine airway smooth muscle. 3. In addition to in vitro studies, the effects of inhalation of the different muscarinic antagonists on lung function parameters in vivo were investigated. Inhalation of 4-DAMP induced a decrease in airway resistance and an increase in lung compliance. In contrast, inhalation of AFDX-116 induced an increase in airway resistance and almost no change in lung compliance. Apart from some minor effects of atropine on airway resistance, atropine, PZ, and pilocarpine failed to induce changes in lung mechanics as determined by in vivo lung function measurements. 4. The results provide evidence for the existence of M3 receptors on murine tracheae that are involved in the contraction of tracheal smooth muscle.(ABSTRACT TRUNCATED AT 250 WORDS)     

Diagnostic value of anti-Candida enolase antibodies.

An immunodominant antigen with enolase enzyme activity was purified and used for the development of an assay to detect antibodies directed against this antigen in sera from patients with either invasive candidiasis or Candida colonization. The Au enzyme-linked immunosorbent assay established with the Candida enolase antigen was able to discriminate significantly between invasive candidiasis and colonization in both immunocompetent and immunodeficient groups of patients. The test had a sensitivity of 50% and a specificity of 86% in the immunocompetent patient group. In the immunodeficient patient group, a sensitivity of 53% and a specificity of 78% were established. Antibody levels determined by a counterimmunoelectrophoresis assay with the same set of sera resulted in a better sensitivity for sera from the immunocompetent patient group but a lower specificity, i.e., 80 and 29%, respectively. The counterimmunoelectrophoresis assay of sera from the immunodeficient patient group was not able to discriminate significantly between invasive candidiasis and colonization. With the use of more serum from each patient, the sensitivity of the antibody detection assays increased, while the specificity was maintained. The increase, however, was not statistically significant. Combining the results of the antibody assays with antigen titers obtained by the Cand-Tec assay did not improve the predictive value with respect to invasive candidiasis, as determined by multivariance regression analysis. Furthermore, it was demonstrated by performance of Western blots (immunoblots) that sera from patients as well as a rabbit antiserum cross-reacted with the Candida enolase and baker's yeast enolase enzyme. However, by tandem crossed immunoelectrophoresis it was demonstrated that the antibodies were directed toward different epitopes of the antigen.     

Simple colorimetric microtiter plate hybridization assay for detection of amplified Mycobacterium leprae DNA.

The detection of amplified products resulting from polymerase chain reactions (PCRs) remains a complicated process. To simplify the detection procedures, we developed a colorimetric microtiter plate hybridization assay for the specific detection of 5'-biotinylated PCR fragments of Mycobacterium leprae DNA. For this assay, an M. leprae DNA capture probe was made and immobilized on the wells of a microtiter plate. Hybridization of the biotin-labeled PCR fragments was detected through enzymatic color development. The resulting optical densities showed a logarithm-linear relationship with the amount of template DNA and corresponded to the intensity of the bands obtained through gel analysis and Southern blotting of the PCR products. The sensitivity of the assay was found to be 125 fg of genomic M. leprae DNA, or 20 lysed bacilli, revealing a detection limit similar to that of agarose gel analysis. The efficient coamplification of human DNA was used as a positive control for the presence of inhibitory substances in clinical material. For detection of human PCR products, a human DNA capture probe was also constructed for the colorimetric assay. This dual setup for hybridization, which thus detected both M. leprae and human DNA PCR products, was useful for ascertaining the presence of inhibiting substances in clinical specimens. All biopsy specimens (n = 10) from untreated patients with leprosy were positive. Apparently, this assay is more sensitive than microscopy, because biopsy specimens from half of the patients were negative upon histopathological examination. Biopsy specimens from three treated patients were negative, as were those from the three patients who did not have leprosy. We conclude that this colorimetric assay can replace agarose gel analysis and Southern hybridization, because it is as sensitive as those methods. Its advantages over conventional gel analysis and Southern hybridization are that it is less cumbersome and more rapid.     

Bovine intestinal alkaline phosphatase attenuates the inflammatory response in secondary peritonitis in mice

Lipopolysaccharide (LPS) contributes importantly to morbidity and mortality in sepsis. Bovine intestinal alkaline phosphatase (BIAP) was demonstrated to detoxify LPS through dephosphorylation. LPS injection combined with BIAP reduced inflammation and improved survival in various experimental settings. In this study, single-dose intravenous administration of BIAP (0.15 IU/g) was applied in a murine cecal ligation and puncture (CLP) model of polymicrobial sepsis. Saline was given as control (S group). Treatment with BIAP prior to CLP (prophylaxis; BIAP-P group) or shortly after (early treatment; BIAP-ET group) reduced cytokine concentrations in plasma and peritoneal lavage fluid (PLF). Tumor necrosis factor-alpha peak levels decreased from 170 pg/ml (S) to 57.5 (BIAP-P) and 82.5 (BIAP-ET) in plasma and in PLF from 57.5 pg/ml (S) to 35.3 (BIAP-P) and 16.8 (BIAP-ET) (all, P < 0.05). Peak interleukin-6 levels in plasma decreased from 19.3 ng/ml (S) to 3.4 (BIAP-P) and 11.5 (BIAP-ET) and in PLF from 32.6 ng/ml (S) to 13.4 (BIAP-P) and 10.9 (BIAP-ET) (all, P < 0.05). Macrophage chemoattractant protein 1 peak levels in plasma decreased from 2.0 ng/ml (S) to 1.0 (BIAP-P) and 0.7 (BIAP-ET) and in PLF from 6.4 (S) to 2.3 (BIAP-P) and 1.3 ng/ml (BIAP-ET) (all, P < 0.05). BIAP-treated groups showed decreased transaminase activity in plasma and decreased myeloperoxidase activity in the lung, indicating reduced associated hepatocellular and pulmonary damage. Survival was not significantly altered by BIAP in this single-dose regimen. In polymicrobial secondary peritonitis, both prophylactic and early BIAP treatment attenuates the inflammatory response both locally and systemically and reduces associated liver and lung damage.