Inhibitory effects of ethaverine, a homologue of papaverine, on monoamine oxidase activity in mouse brain

The effects of benzylisoquinoline compounds such as ethaverine, laudanosine, and tetrahydropapaverine on monoamine oxidase (MAO, EC 1.4.3.4) activity in mouse brain were investigated. Ethaverine showed an inhibition of MAO activity in a concentration-dependent manner (57.6% inhibition at 40 microm). Papaverine also inhibited MAO activity (38.1% inhibition at 40 microM). However, laudanosine and tetrahydropapaverine did not inhibit MAO activity. The IC50 value of ethaverine for MAO was 25.5 microm. Ethaverine non-competitively inhibited MAO activity with a substrate kynuramine. The Ki value for ethaverine was 11.9 microM. In addition, ethaverine proved to preferentially inhibit type B MAO activity in a concentration-dependent manner, with an IC50 value of 32.8 microm. These results suggest that ethaverine partially contributes to the regulation of catecholamine content.

Acemannan purified from Aloe vera induces phenotypic and functional maturation of immature dendritic cells

Acemannan, a major carbohydrate fraction of Aloe vera gel, has been known to have antiviral and antitumoral activities in vivo through activation of immune responses. The present study was set out to define the immunomodulatory activity of acemannan on dendritic cells (DCs), which are the most important accessory cells for the initiation of primary immune responses. Immature DCs were generated from mouse bone marrow (BM) cells by culturing in a medium supplemented with GM-CSF and IL-4, and then stimulated with acemannan, sulfated acemannan, and LPS, respectively. The resultant DCs were examined for phenotypic and functional properties. Phenotypic analysis for the expression of class II MHC molecules and major co-stimulatory molecules such as B7-1, B7-2, CD40 and CD54 confirmed that acemannan could induce maturation of immature DCs. Functional maturation of immature DCs was supported by increased allogeneic mixed lymphocyte reaction (MLR) and IL-12 production. The differentiation-inducing activity of acemannan was almost completely abolished by chemical sulfation. Based on these results, we propose that the adjuvant activity of acemannan is at least in part due to its capacity to promote differentiation of immature DCs.

Macroscopic chirality of a liquid crystal from nonchiral molecules

The transfer of chirality from nonchiral polymer networks to the racemic B2 phase of nonchiral banana-shaped molecules is demonstrated. This corresponds to the transfer of chirality from an achiral material to another achiral material. There are two levels of chirality transfers. (a) On a microscopic level the presence of a polymer network (chiral or nonchiral) favors a chiral state over a thermodynamically stable racemic state due to the inversion symmetry breaking at the polymer-liquid crystal interfaces. (b) A macroscopically chiral (enantimerically enriched) sample can be produced if the polymer network has a helical structure, and/or contains chemically chiral groups. The chirality transfer can be locally suppressed by exposing the liquid crystal to a strong electric field treatment.

Retroperitoneal fibrosis with duodenal stenosis

Retroperitoneal fibrosis is a rare disease characterized by the formation of dense plaque of fibrous tissue covering the retroperitoneal structures. This disease is commonly presented as ureteral obstruction, but the involvement of duodenum is rare. We report a case of retroperitoneal fibrosis which was complicated with duodenal stenosis and was successfully treated with corticosteroids. A 58-yr-old man, who had history of aorto-iliac bypass graft due to arteriosclerosis obliterans with infrarenal aortic occlusion was admitted to the hospital with abdominal pain and a mass. Abdominal CT scan revealed the periaortic soft tissue mass encircling grafted aorta and stenosis of duodenal third portion. Retroperitoneal fibrosis with duodenal stenosis was diagnosed and prednisolone therapy was initiated. Follow-up CT scan showed that the patient responded to prednisolone therapy with eased pain, shrinking periaortic mass, and reduced duodenal stenosis.

Generation of macrophages from early T progenitors in vitro

Early T progenitors in the thymus have been reported to have the capacity to develop into B cells, thymic dendritic cells, and NK cells. Here we describe conditions that induce early T progenitors to develop into macrophages. Initially, we observed that early T progenitors could be induced to develop into macrophages by cytokines produced from a thymic stromal cell line, TFGD, and later we found that the cytokine mixture of M-CSF plus IL-6 plus IL-7 also induced macrophage differentiation from pro-T cells. M-CSF by itself was unable to induce macrophage differentiation from early T progenitors. To correlate this observation with the developmental potential of early T progenitors, mouse embryonic thymocytes were sorted into four populations, pro-T1 to pro-T4, based on the expression of CD44 and CD25, and then cultured with TFGD culture supernatant. We found that pro-T1 and pro-T2 cells, but not pro-T3 and pro-T4 cells, generate macrophages. Limiting dilution analysis of the differentiation capability of sorted pro-T2 cells also confirmed that pro-T2 cells could generate macrophages. These results suggest that T cells and thymic macrophages could originate from a common intrathymic precursor.

Evaluation of five commercial serological tests for the detection of Helicobacter pylori infection in Chinese

BACKGROUND

Commercial serological tests for the detection of Helicobacter pylori infection must be locally validated. We evaluated the accuracy of five commercial tests in the Chinese population.

METHODS

Serum samples were collected from patients referred for upper endoscopy. Antral biopsies were taken for histological examination and culture of H. pylori. The gold standard for diagnosing H. pylori infection was positive histological staining and/or positive H. pylori culture. The serum samples were tested for H. pylori antibodies using the following tests: (i) Cobas Core Anti-H. pylori EIA; (ii) GAP IgG; (iii) GAP IgM; (iv) H. pylori microwell EIA (Quidel); and (v) Premier H. pylori. The sensitivity, specificity and accuracy of each test was calculated according to the manufacturers' instructions or according to a new cut-off value.

RESULTS

A total of 158 patients were recruited amongst whom 114 (72%) were H. pylori-positive. Indeterminate results varied from 7% to 19%. The accuracy of the tests varied from 57% to 85%. By using new cut-off values, the accuracy was much improved, ranging from 73.4% to 86.7%.

CONCLUSIONS

By defining new cut-off values for the Chinese population, we were able to improve the performance of some of the serology tests. This illustrates the importance of local validation.

Vaccination against Helicobacter pylori in non-human primate models and humans

Several vaccination studies have been performed in monkeys and humans testing the feasibility of prophylactic and therapeutic immunizations against Helicobacter pylori. The monkey studies showed that immune responses were induced by oral vaccination with the mucosal adjuvant LT (Escherichia coli heat-labile enterotoxin), parenteral administration with a cationic lipid adjuvant, and by mucosal priming followed by parenteral boosts. Both prophylactic and therapeutic activities were demonstrated in monkeys, providing a strong impetus for human vaccine trials. Preliminary studies in humans were undertaken in order to identify a tolerable dose of LT adjuvant or to test the effectiveness of mutant atoxic LT adjuvants. The results from these preliminary studies suggest that native LT causes diarrhoea at doses required for adjuvanticity while a mutant LT does not. In one study in which infected human subjects were vaccinated with orally administered urease antigen with native LT, there was a modest reduction in the level of H. pylori gastric colonization. A second clinical study employing H. pylori whole cell antigen and a mutant LT in infected subjects showed immune responses and although the subjects remained infected, the study was not designed to measure reduction in H. pylori colonization. Recombinant Salmonella expressing urease and other H. pylori antigens have been effective in mice (see accompanying Frontlines Topic Review by John O. Nedrud [1]), but monkey studies are not possible because of host range restriction. Human trials of parenteral immunization, mucosal immunization with mutant LT and live Salmonella vectors are needed to fully assess the ability of vaccines to prevent or treat H. pylori infections.

Effect of different endotracheal suctioning systems on cardiorespiratory parameters of ventilated patients

INTRODUCTION

We conducted this prospective randomised cross-over study to evaluate the effect of closed system (CS) versus open system (OS) endotracheal suctioning on heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), oxygen saturation (SpO2) and electrocardiogram (ECG) rhythm of patients on mechanical ventilation.

MATERIALS AND METHODS

Fourteen adult patients were randomly allocated to receive either CS or OS suctioning in the first instance. For the subsequent suctioning, they were crossed over to the alternate suctioning system. The various cardiorespiratory parameters were recorded at BL1 (baseline 1), S1 (first suction pass), BL2 (baseline 2, i.e. immediately post first suction pass), S2 (second suction pass), T2 (2 minutes post suction) and T5 (5 minutes post suction).

RESULTS

Compared to CS, OS suctioning was found to result in higher HR at S1 (P < or = 0.05) and S2 (P < or = 0.05); higher MAP at BL2 (P < or = 0.05); lower SpO2 at BL2 (P < or = 0.01) and S2 (P < or = 0.01). There was no significant difference in RR between the two suctioning systems. OS suctioning was also noted to result in a significantly higher incidence of arrhythmia (P < = or 0.05).

CONCLUSION

Our study shows that OS suctioning results in more adverse changes in cardiorespiratory parameters compared to CS suctioning.

Immunogenicity of the E1E2 proteins of hepatitis C virus expressed by recombinant adenoviruses

The E1 and E2 proteins of hepatitis C virus (HCV) are believed to be the viral envelope glycoproteins that are major candidate antigens for HCV vaccine development. We reported previously that the replication-competent recombinant adenovirus encoding core-E1-E2 genes of HCV (Ad/HCV) produces serologically reactive E1 and E2 proteins forming a heterodimer in substantial amounts. Here, we examined immunogenicity of the E1E2 proteins copurified from HeLa cells infected with Ad/HCV virus in mice. Furthermore, we constructed a replication-defective recombinant adenovirus encoding the core-E1-E2 genes of HCV (Ad.CMV.HCV) and examined immunogenicity of the virus in mice. The mice immunized intraperitoneally with the copurified E1E2 proteins induced mainly antibodies to E2, but not to E1 by Western blot analysis. The sera of mice immunized with the E1E2 inhibited the binding of E2 protein to the major extracellular loop of human CD81. E2-specific cytotoxic T cells (CTLs), but not antibodies to the E1E2 antigens were induced in the mice intramuscularly immunized with Ad.CMV.HCV virus. When immunized with both Ad.CMV.HCV virus and the E1E2, mice elicited E2-specific CTLs and antibodies to the E1E2 antigens. The results suggest that immunization of Ad.CMV.HCV virus combined with E2 protein is an effective modality to induce humoral as well as cellular immune response to E2 antigen.

Serum ferritin as a serologic marker of activity in systemic lupus erythematosus

To investigate the relationship between serum ferritin and disease activity in systemic lupus erythematosus (SLE), we enrolled 128 patients with SLE (18 males and 110 females). Twenty-eight patients (2 males and 26 females) with rheumatoid arthritis (RA) served as controls. The SLE patients were subdivided into three groups according to Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores: groups A (0-5), B (6-9), and C (> or =10). We prospectively evaluated 48 SLE patients before and after treatment. Serum ferritin and anti-dsDNA antibody were measured by radioimmunometric assay. C-reactive protein (CRP) was measured quantitatively by immunonephelometry. Complements 3 and 4 (C3 and C4) were measured by nephelometry. Serum levels of ferritin during the more active stage of SLE (group C) exceeded those of RA patients and patients at less active stages of SLE (groups A and B). There were no significant differences between RA patients and groups A and B. Serum ferritin was elevated especially in serositis and hematologic manifestation. In this prospective study, changes in SLEDAI scores before and after treatment correlated significantly with serum ferritin levels and inversely to C3 and C4 levels. We confirm that serum ferritin levels can be a useful marker of disease activity in SLE patients.

Synthesis and antiviral activity of novel exomethylene cyclopropyl nucleosides

Novel cyclopropyl nucleosides were synthesized as potential antiviral agents. The key intermediate 5, prepared from Feist's acid 1 was condensed with purine derivatives by the SN2 type reaction. All the synthesized compounds were evaluated for antiviral activity.

Novel nucleosides with vinyl fluoride or vinyl bromide moiety as open-chain analogs of neplanocin A

Novel nucleosides with vinyl fluoride and vinyl bromide were designed, synthesized and evaluated their antiviral activities against poliovirus, HSV, HIV, and HBV.

Lack of relationship between vitamin D receptor polymorphism and bone erosion in rheumatoid arthritis

We performed this study to investigate the possible association between vitamin D receptor (VDR) gene polymorphism and the focal bone erosion in rheumatoid arthritis (RA) patients in Korea. One hundred and fifty-seven RA patients were enrolled and two control groups were selected. The focal bone erosion score was assessed by modified Sharp's method. Genotyping of VDR polymorphisms was performed by polymerase chain reaction and restriction fragment length polymorphism analysis using two restriction enzyme Taq I and Bsm I. Notably, the distribution of VDR genotype in Korean population was different from Caucasians. The frequencies of "tt" and "BB" genotypes were very rare both in RA patients and in control groups. The frequency distribution of the Taq I and Bsm I genotype was not different between RA patients (TT, 93.6%; Tt, 6.4%; tt, 0%; BB, 0.6%; Bb, 5.1%; bb, 94.3%) and control groups (TT, 90.8%; Tt, 7.5%; tt, 1.7%; BB, 1.4%; Bb, 8.1%; bb, 90.5%). There was no significant difference in the focal bone erosion score (mean +/- SD) according to the VDR genotypes of RA patients (TT, 0.92 +/- 1.79; Tt, 0.4 +/- 0.79; Bb, 0.43 +/- 0.80; bb, 0.92 +/- 1.79; p > 0.05). In conclusion, these results suggest that VDR gene polymorphisms are not associated with the focal bone erosion in RA patients in Korea.

Diterpenoids from the leaves of Juniperus chinensis var. kaizuka

Two diterpenoids based on novel carbon skeletons, namely, 8,19-dioxo-8,14-seco-chinan-14,11-olide (1) and 8-oxo-8,14-seco-abiet-12-en-14,19-dial (2), have been isolated, together with two new abietane diterpenoids, 13 beta,14 beta-epoxyabiet-7-en-19,6 beta-olide (3) and 7 beta-hydroxyabieta-8,11,13-trien-19-al (4), from the leaves of Juniperus chinensis. Their structures were determined by spectroscopic methods, including 2D NMR, and, in the case of 1, X-ray crystallographic analysis.

Identification of the varR gene as a transcriptional regulator of virginiamycin S resistance in Streptomyces virginiae

A gene designated varR (for virginiae antibiotic resistance regulator) was identified in Streptomyces virginiae 89 bp downstream of a varS gene encoding a virginiamycin S (VS)-specific transporter. The deduced varR product showed high homology to repressors of the TetR family with a conserved helix-turn-helix DNA binding motif. Purified recombinant VarR protein was present as a dimer in vitro and showed clear DNA binding activity toward the varS promoter region. This binding was abolished by the presence of VS, suggesting that VarR regulates transcription of varS in a VS-dependent manner. Northern blot analysis revealed that varR was cotranscribed with upstream varS as a 2.4-kb transcript and that VS acted as an inducer of bicistronic transcription. Deletion analysis of the varS promoter region clarified two adjacent VarR binding sites in the varS promoter.

Microarray profiling of gene expression in aging and its alteration by caloric restriction in mice

An active research area in biological gerontology concerns the mechanisms by which caloric restriction (CR) retards the aging process in laboratory rodents. We used high density oligonucleotide arrays representing 6347 genes to determine the gene expression profile of the aging process in gastrocnemius muscle of male C57BL/6 mice. Aging resulted in a differential gene expression pattern indicative of a marked stress response and lower expression of metabolic and biosynthetic genes. Most alterations were completely or partially prevented by CR. Transcriptional patterns of muscle from calorie-restricted animals suggest that CR retards the aging process by causing a metabolic shift toward increased protein turnover and decreased macromolecular damage. The use of high density oligonucleotide microarrays provides a new tool to measure biological age on a tissue-specific basis and to evaluate at the molecular level the efficacy of nutritional interventions designed to retard the aging process.

Syntheses and structure--activity relationships of novel apio and thioapio dideoxydidehydronucleosides as anti-HCMV agents

On the basis of the fact that apio dideoxynucleosides, in which the furanose oxygen and the C2 of the 2,3-dideoxyribose are transposed, exhibited potent anti-HIV activity and 2',3'-dideoxy-2',3'-didehydronucleosides also showed potent anti-HIV activity, we synthesized apio dideoxydidehydronucleosides in which the oxygen atom and the double bond of the 2,3-dideoxy-2,3-didehydroribose are exchanged. The thioapio dideoxydidehydronucleosides were also synthesized since sulfur serves as a bioisostere of oxygen. Apio dideoxydidehydronucleosides 13a--f were synthesized starting from 1,3-dihydroxyacetone, utilizing phenylselenenyl chemistry as a key step. The ratio of the anomeric mixture was variable from 1:1 to 5:1 during the condensation of nucleosidic bases with the phenylselenyl acetate 11 in the presence of a Lewis acid. This is in contrast with other glycosyl donors such as 5-O-(tert-butyldiphenylsilyl)-2-phenylselenenyl-2,3-dideoxyribosyl acetate which shows excellent neighboring group effect (alpha:beta = 1:99). Thioapio dideoxydidehydronucleosides 22a,b were synthesized from the lactone 9 via thiolactone 17 as a key intermediate which was synthesized from dicyclohexylcarbodiimide coupling of the mercapto acid produced from the basic hydrolysis of thioacetate 16. The majority of apio analogues synthesized in this study exhibited moderate to potent anti-HCMV activity, among which the 5-fluorouracil derivative 13c was found to be the most potent against HCMV, while thioapio analogues showed no activity against HCMV. However, all synthesized compounds did not exhibit any significant activities against HIV-1, HSV-1, and HSV-2. The fact that apio dideoxydidehydronucleosides were active against HCMV suggests that the apio dideoxydidehydro sugar moiety can serve as a novel template for the development of new antiviral agents.

Pulmonary alveolar hemorrhage in patients with rheumatic diseases in Korea

Pulmonary alveolar hemorrhage (PAH) is a rare and often fatal presenting feature of rheumatic diseases, with high mortality rate ranging from 40% to 90%. This study was undertaken to review the clinical manifestations, disease course, prognosis, and treatment of PAH in rheumatic diseases in Korea. A retrospective analysis was performed from October 1995 to March 1999 at the Samsung Medical Center. Ten cases were diagnosed as having pulmonary hemorrhage with rheumatic diseases that comprised the following: 6 systemic lupus erythematosus (SLE), 3 microscopic polyangiitis (MPA), and 1 mixed connective tissue disease (MCTD). In 80% of the patients in the present series, PAH was the first clinical manifestation of rheumatic diseases. The most consistent systemic manifestation occurring in conjunction with PAH was renal involvement (80%). The overall patient mortality rate was 50% (5/10) in the current series. Our study suggests that PAH often occurs as the first clinical manifestation of rheumatic diseases and needs urgent medical treatment including plasmapheresis in addition to cyclophosphamide and methylprednisolone.

Mode of antiviral activity of water soluble components isolated from Elfvingia applanata on vesicular stomatitis virus

A preparation of water soluble components (EA) was made from carpophores of Elfvingia applanata (Pers.) Karst and its in vitro antiviral activity on vesicular stomatitis virus [(Indiana serotype, VSV(IND)] was investigated by plaque reduction assay. EA exhibited potent antiviral activity on VSV(IND) growth and negligible cytotoxicity on Vero cells, 50% effective concentration (EC50) of 104 microg/ml and 50% cytotoxic concentration (CC50) of 3,793 microg/ml, respectively. Selectivity index (SI, CC50/EC50) of EA on Vero cell and VSV(IND) was about 36.5. EA did not display either a direct virucidal effect on VSV(IND) or induction of antiviral substance by Vero cells upon its treatment. Thus, the mode of antiviral activity of EA was studied at steps of viral adsorption onto cell. When both EA and virus were added to cell monolayers, titer of cell-free virus in culture supernatant increased in ca. 30-40% compared with that of control group and titer of cell-associated virus was 60-100% higher than that of control group. These results suggested that antiviral activity of EA on VSV(IND) might be due to the hindrance of viral entry to cells at either endocytosis or loss of envelope.

Inhibitory effects of ethaverine, a homologue of papaverine, on dopamine content in PC12 cells

The inhibitory effects of ethaverine on dopamine content in PC12 cells were investigated. Ethaverine decreased dopamine content in a concentration-dependent manner in PC12 cells and showed 33.6% inhibition of dopamine content at a concentration of 1.0 microM for 24-48 h. The IC50 value of ethaverine was 1.4 microM. Dopamine content was lowered at 6h and reached a minimal level at 12h after exposure to ethaverine at 2.0 microM. The decreased dopamine level was maintained up to 48 h and then recovered to the control level at about 72 h. Tyrosine hydroxylase (TH) was inhibited at 6 h following treatment with ethaverine in PC12 cells and the activity was maintained at a reduced level up to 36 h (12-22% inhibition at 2.0 microM). These results indicate that ethaverine leads to a decrease in dopamine content by inhibition of TH activity.

Quaternized wood as sorbent for hexavalent chromium

The potential of quaternized wood (QW) chips in removing hexavalent chromium from synthetic solution and chrome waste under both batch and continuous-flow conditions was investigated. Sorption was found to be dependent on pH, metal concentration, and temperature. QW chips provide higher sorption capacity and wider pH range compared with untreated wood chips. The equilibrium data could be fitted into the Langmuir isotherm model, and maximum sorption capacities were calculated to be 27.03 and 25.77 mg/g in synthetic chromate solution and chrome waste, respectively. The presence of sulfate in high concentration appeared to suppress the uptake of chromium by QW chips. Column studies showed that bed depth influenced the breakthrough time greatly whereas flow rate of influent had little effect on its sorption on the column.

6-Hydroxy-1,3-dioxin-4-ones as non-peptidic HIV protease inhibitors

HIV protease inhibitors containing 6-hydroxy-1,3-dioxin-4-one ring system as a new scaffold have been prepared. Among them, compound 4d showed potent HIV protease inhibitory activity (IC50 = 0.01 microM) and antiviral activity in cell culture (EC50 = 0.96 microM, SI = 65.69).

Synthesis and antiviral activity of novel methylene cyclopropyl nucleosides

Novel exomethylene cyclopropyl nucleosides were synthesized as potential antiviral agents. The key intermediate 5 was synthesized in 4 steps, from Feists acid 1 and was condensed with purine derivatives by the SN2 type reaction to give some cyclopropyl nucleosides. The synthesized nucleosides did not showed any significant antiviral activity against HSV-1, HSV-2, HCMV, HIV-1, HIV-2, and HBV up to 100 microM.