IL-4-induced oxidative stress upregulates VCAM-1 gene expression in human endothelial cells

Vascular cell adhesion molecule-1 (VCAM-1) is expressed in early stages of atherosclerosis; however, the mechanisms of its upregulation are not fully understood. In the present study, we examined the effects of interleukin-4 (IL-4) on VCAM-1 gene expression and its transcriptional regulatory mechanism in human umbilical vein endothelial cells (HUVEC). Reverse transcription-polymerase chain reaction showed that VCAM-1 mRNA was induced in IL-4-treated HUVEC in a time- and dose-dependent manner. Among known transcription factors that have binding sites in the promoter region of the VCAM-1 gene, IL-4 activated only SP-1. In contrast, nuclear factor- kappa B (NF- kappa B), activator protein-1 (AP-1) and interferon regulatory factor-1 (IRF-1), which also have consensus binding sequences in the 5'-flanking region of the human VCAM-1 gene, were not activated. The role of SP-1 in IL-4-induced VCAM-1 expression was confirmed in HUVEC transfected with a reporter construct of the VCAM-1 promoter with mutated SP-1 binding site. As IL-4 treatment of HUVEC enhanced the intracellular oxidizing potential, as indicated by an increase in 2',7'-dichlorofluorescein (DCF) fluorescence, we studied the effect of antioxidants on IL-4-induced VCAM-1 expression. Pretreatment of HUVEC with pyrrolidine dithiocarbamate (PDTC) or N-acetylcysteine (NAC) completely prevented IL-4-induced VCAM-1 expression. In addition, PDTC inhibited IL-4-related activation of SP-1. These results suggest that IL-4-induced oxidative stress upregulates the expression of VCAM-1 gene in HUVEC at transcriptional levels via activation of SP-1 transcription factor. In contrast, NF- kappa B, AP-1 or IRF-1 do not appear to be involved in the signal transduction cascade.

The value of contrast echocardiography in the diagnosis of patent ductus arteriosus with Eisenmenger's syndrome

When patent ductus arteriosus (PDA) is complicated by pulmonary hypertension resulting in a right-to-left shunt, an erroneous diagnosis of primary pulmonary hypertension may be made, even after echocardiographic examination. Among the 8 patients referred to our echocardiography laboratory with the diagnosis of primary pulmonary hypertension between June 1994 and November 1999, 2 patients were found to have PDA with Eisenmenger's syndrome. Patent ductus arteriosus with Eisenmenger's syndrome can be diagnosed by the opacification of the abdominal aorta without opacification of the left-sided chambers during contrast echocardiography.

Dose-response assessment by a fuzzy linear-regression method

Regression analysis has been used to characterize the relationship between an exposure dose and the incidence of an adverse health effect such as cancer. However, the regression rarely describes the true relationship due to uncertainties in dose-response data and relationships. Therefore, a method is developed to perform dose-response assessments by a fuzzy linear regression which explicitly exhibit these uncertainties. This method is applied to define the relationship between a particular nitrate dose to humans and its corresponding cancer risk.

IL-4 induces apoptosis of endothelial cells through the caspase-3-dependent pathway

The present study was designed to investigate the hypothesis that interleukin-4 (IL-4) can induce apoptosis of human endothelial cells and to study regulatory pathways of this process. Indeed, DNA ladder assay and flow cytometry study showed that IL-4 can induce apoptosis of endothelial cells in a time- and dose-dependent manner. In addition, IL-4 markedly increased activity of caspase-3, and inhibition of this enzyme suppressed IL-4-induced apoptosis in a dose-dependent manner. These results provide the first evidence that IL-4 can induce apoptosis of human endothelial cells. In addition, the data indicate that the caspase-3-dependent pathway is critically involved in this process.

Apicidin, a histone deacetylase inhibitor, inhibits proliferation of tumor cells via induction of p21WAF1/Cip1 and gelsolin

Apicidin [cyclo(N-O-methyl-L-tryptophanyl-L-isoleucinyl-D-pipecolinyl -L-2-amino-8-oxodecanoyl)] is a fungal metabolite shown to exhibit antiparasitic activity by the inhibition of histone deacetylase (HDAC). In this study, we evaluated apicidin as a potential antiproliferative agent. Apicidin showed a broad spectrum of antiproliferative activity against various cancer cell lines, although with differential sensitivity. The antiproliferative activity of apicidin on HeLa cells was accompanied by morphological changes, cell cycle arrest at G1 phase, and accumulation of hyperacetylated histone H4 in vivo as well as inhibition of partially purified HDAC in vitro. In addition, apicidin induced selective changes in the expression of p21WAF1/Cip1 and gelsolin, which control the cell cycle and cell morphology, respectively. Consistent with increased induction of p21WAF1/Cip1, phosphorylation of Rb protein was markedly decreased, indicating the inhibition of cyclin-dependent kinases, which became bound to p21WAF1/Cip1. The effects of apicidin on cell morphology, expression of gelsolin, and HDAC1 activity in vivo and in vitro appeared to be irreversible, because withdrawal of apicidin did not reverse those effects, whereas the induction of p21WAF1/Cip1 by apicidin was reversible. Taken together, the results suggest that induction of histone hyperacetylation by apicidin is responsible for the antiproliferative activity through selective induction of genes that play important roles in the cell cycle and cell morphology.

Cytotoxicity and L-amino acid oxidase activity of crude insect drugs

The cytotoxicity of crude insect drugs was measured using HeLa cells originating from human cervix and uterine cancer, using the dye uptake assay in order to find potential anticancer agents. Three kinds of extracts (buffer, methanol and ethylacetate) were prepared from 26 insects and used as raw materials for the activity assay. Among these, the buffer extracts from Tabanus, Mylabris and Huechys showed a potent anticancer activity, and those from Catharsius, Red ant, Scorpion, Tabanus and Vespae Nidus showed a strong L-amino acid oxidase (AAO) activity as well as cytotoxicity. In contrast, buffer extracts from Gryllotalpa orientalis and Apriona germari larvae showed greater/more rapid Hela cell growth than that of other insects.

Differentiation between reversible and irreversible restrictive left ventricular filling patterns with the use of mitral annulus velocity

A restrictive left ventricular filling pattern is generally recognized as an ominous prognostic sign in patients with congestive heart failure. Recently, this filling pattern has been further categorized into reversible and irreversible groups according to the changes in the mitral inflow pattern after preload reduction; furthermore, the prognosis is reported to be different for the two groups. Forty-two patients with a restrictive left ventricular filling pattern who could adequately perform Valsalva's maneuver were studied. Baseline peak early (E) and late (A) mitral inflow velocities, E/A ratio, deceleration time of E velocity, peak early (E') and late (A') diastolic mitral annulus velocities, and E'/A' ratio were obtained. During Valsalva's maneuver, the E/A ratio reversed (<1) in fifteen patients (15/42, 36%). These patients were categorized as belonging to the reversible group. Among the baseline mitral inflow and mitral annulus velocity parameters, A' > 0.05 m/s best discriminated between the reversible and irreversible restrictive left ventricular filling patterns, with a sensitivity of 80% and a specificity of 85%.

Reduction of aflatoxins by Korean soybean paste and its effect on cytotoxicity and reproductive toxicity--part 1. Inhibition of growth and aflatoxin production of Aspergillus parasiticus by Korean soybean paste (Doen-jang) and identification of the active component

The inhibitory effect of methanol extract of Korean soybean paste on the mold growth and aflatoxin production of a toxigenic strain of Aspergillus parasiticus ATCC 15517 was studied using different concentrations of the extract in yeast-extract sucrose broth. While inhibition in mold growth due to increasing the concentration of the extract was observed, the more remarkable effect was the inhibition of aflatoxin production. Reduction of mycelial weight as a result of addition of the extract was observed to range between 1.5 to 12.9% while reduction of aflatoxin production quantified by high-performance liquid chromatography ranged from 14.3 to 41.7%. Five percent of the extract significantly reduced aflatoxin production at the end of the incubation period (P < 0.05), although the effect on mycelial growth was less pronounced. This study indicates that soybean paste could also be an effective inhibitor of aflatoxin production even though mycelial growth may be permitted. The main active component identified by gas chromatography-mass spectroscopy was linoleic acid.

2-Amino-3-methylimidazo[4,5-f]quinoline inhibits nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 cells by blocking p38 kinase activation

We show that 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), a heterocyclic amine, significantly inhibits nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophages. The decrease in NO production was found to correlate well with a decrease in inducible NO synthase (iNOS) mRNA expression as demonstrated by Northern blot analysis. Treatment of RAW 264.7 cells with IQ selectively inhibited the activation of NF-kappaB/Rel, an important transcription factor of iNOS gene expression, while neither AP-1 nor Oct was affected by IQ. Since iNOS transcription has been shown recently to be under the control of the p38 kinase signaling cascade, we assessed the effect of IQ on p38 kinase activation. Treatment of RAW 264.7 with IQ inhibited LPS-stimulated p38 kinase phosphorylation in a dose-related manner. IQ also inhibited the p38 kinase activity. Collectively, this series of experiments indicates that IQ inhibits LPS-induced expression of iNOS gene in RAW 264.7 cells. Based on our findings, the most likely mechanism that can account for this biological effect involves the negative regulation of NF-kappaB/Rel and p38 kinase pathway.

Dexamethasone inhibits IL-1 beta gene expression in LPS-stimulated RAW 264.7 cells by blocking NF-kappa B/Rel and AP-1 activation

In the present study, the mechanism by which dexamethasone (DEX) inhibited IL-1beta gene expression in bacterial lipopolysaccharide (LPS)-activated RAW 264.7 cells was investigated. The decrease in LPS-induced IL-1beta mRNA expression was demonstrated by quantitative reverse transcription polymerase chain reaction (RT-PCR). Since the promoter in IL-1beta gene contains binding motifs for NF-kappaB/Rel, AP-1, NF-IL6, and CREB/ATF, which appear to be important in LPS-mediated IL-1beta induction, the effects of DEX on the activation of these transcription factors were examined. Treatment of DEX to RAW 264.7 cells induced a dose-related inhibition of NF-kappaB/Rel and AP-1 in chloramphenicol acetyltransferase activity, while neither NF-IL6 nor CREB/ATF activation was affected by DEX. Treatment of RAW 264.7 cells with DEX inhibited DNA binding of NF-kappaB/Rel and AP-1 proteins to their cognate DNA sites as measured by electrophoretic mobility shift assay (EMSA). DEX treatment caused a significant reduction in nuclear c-rel, p65, and p50 protein contents, and these decreases were paralleled by the accumulation of cytoplasmic c-rel, p65, and p50. DEX treatment of RAW 264.7 cells did not inhibit the nuclear translocation of c-jun and c-fos. We found that the inhibition of IL-1beta production by DEX is not related to p38, which is important in the IL-1beta induction. These results suggest that DEX may inhibit IL-1beta gene expression by a mechanism involving the blocking of LPS-induced NF-kappaB/Rel and AP-1 activation.

Effect of oxidized frying oil and vitamin C levels on the hepatic xenobiotic-metabolizing enzyme system of guinea pigs

The influence of oxidized frying oil (OFO) on the guinea pig hepatic microsomal xenobiotic-metabolizing enzyme system in the presence of different amounts dietary vitamin C was investigated. Weanling male guinea pigs were divided into four groups and were fed 15% oxidized frying oil diets supplemented with vitamin C at 300, 600, or 1,500 mg/kg (experimental diets) or a control diet that contained 15% fresh untreated soybean oil with 300 mg/kg of vitamin C, respectively. After 60 d, guinea pigs were euthanized and phase I and phase II xenobiotic-metabolizing enzymes in the liver were determined. Compared with the fresh oil diet fed the control group, the relative liver weight was higher in the OFO-fed groups. Hepatic microsomal protein and cytochrome P450 contents were significantly higher in OFO-fed guinea pigs than in the control group. Both values increased in response to increased intake of vitamin C. The activities of phase II relative components, including UDP-glucuronyl transferase, UDP-glucuronyl dehydrogenase and beta-glucuronidase, of guinea pigs fed the OFO diets supplemented with 300 mg vitamin C/kg were significantly higher than those of guinea pigs fed the control diet. However, the phase II relative components decreased with increasing vitamin C content in the diet. The results demonstrate that both dietary OFO and vitamin C in guinea pigs induce hepatic xenobiotic-metabolizing enzymes, but the level of induction is modulated by the dietary vitamin C level.

Molecular characterization of a dimeric intracellular maltogenic amylase of Bacillus subtilis SUH4-2

An additional amylase besides the typical alpha-amylase was detected in the cytoplasm of Bacillus subtilis SUH4-2, an isolate from Korean soil. The corresponding gene encoded a maltogenic amylase, which hydrolyzed cyclodextrin or starch to maltose and glucose; pullulan to panose; acarbose to glucose and acarviosine-glucose. Maltogenic amylase of B. subtilis SUH4-2 transferred sugar molecules to form various branched oligosaccharides upon the hydrolysis of substrates. The enzyme existed in a monomer-dimer equilibrium with a molar ratio of 3:2 in 50 mM KH(2)PO(4)-NaOH buffer (pH 7.0). The maltogenic amylase is most likely to be associated with carbohydrate metabolism in the cytoplasm, since the nucleotide sequence of the gene was highly homologous to the yvdF gene of B. subtilis 168, which is located in a gene cluster involved in maltose/maltodextrin utilization.

Optimization of resolution and color reproduction by controlling luminance and contrast levels of a liquid-crystal display monitor

The image quality of a color liquid-crystal display monitor is studied by changing the contrast and the luminance levels. The resolution is assessed with modulation transfer function area (MTFA) that is measured at nine different combinations of the luminance and contrast. At these combinations, we measure the chromaticity coordinates and luminance of red-green-blue channels as a function of the digital-analog convert value. We analyze the relations among MTFA value, constant-channel chromaticity, color gamut, and maximum luminance of a white pattern. From the results, the combination of levels is found that provides both high resolution and good color reproduction.

A comparison of EGF and MAb 528 labeled with 111In for imaging human breast cancer

Our objective was to compare 111In-labeled human epidermal growth factor (hEGF), a 53-amino acid peptide with anti-epidermal growth factor receptor (EGFR) monoclonal antibody (MAb) 528 (IgG2a) for imaging EGFR-positive breast cancer.

METHODS

hEGF and MAb 528 were derivatized with diethylenetriamine pentaacetic acid (DTPA) and labeled with 111In acetate. Receptor binding assays were conducted in vitro against MDA-MB-468 human breast cancer cells. Biodistribution and tumor imaging studies were conducted after intravenous injection of the radiopharmaceuticals in athymic mice bearing subcutaneous MCF-7, MDA-MB-231, or MDA-MB-468 human breast cancer xenografts or in severe combined immunodeficiency mice implanted with a breast cancer metastasis (JW-97 cells). MCF-7, MDA-MB-231, JW-97, and MDA-MB-468 cells expressed 1.5 x 10(4), 1.3 x 10(5), 2.7 x 10(5), and 1.3 x 106 EGFR/cell, respectively in vitro.

RESULTS

111In-DTPA-hEGF and 111In-DTPA-MAb 528 bound with high affinity to MDA-MB-468 cells (Ka of 7.5 x 10(8) and 1.2 x 10(8) L/mol, respectively). 111In-DTPA-hEGF was eliminated rapidly from the blood with < 0.2% injected dose/g (%ID/g) circulating at 72 h after injection, whereas 111In-DTPA-MAb 528 was cleared more slowly (3%ID/g in the blood at 72 h). Maximum localization of 111In-DTPA-hEGF in MDA-MB-468 tumors (2.2 %ID/g) was 10-fold lower than with 111In-DTPA-MAb 528 (21.6 %ID/g). There was high uptake in the liver and kidneys for both radiopharmaceuticals. Tumor-to-blood ratios were greater for 111In-labeled hEGF than for MAb 528 (12:1 versus 6:1), but all other tumor-to-normal tissue ratios were higher for MAb 528. MDA-MB-468 and JW-97 tumors were imaged successfully with both radiopharmaceuticals, but tumors were more easily visualized using 111In-labeled MAb 528. There was no direct quantitative relationship between EGFR expression on breast cancer cell lines in vitro, and tumor uptake of the radiopharmaceuticals in vivo, but control studies showed that tumor uptake was receptor mediated.

CONCLUSION

Our results suggest that the tumor uptake in vivo of receptor-binding radiopharmaceuticals is controlled to a greater extent by their elimination rate from the blood than by the level of receptor expression on the cancer cells. Radiolabeled anti-EGFR MAbs would be more effective for tumor imaging in cancer patients than peptide-based radiopharmaceuticals such as hEGF, because they exhibit higher tumor uptake at only moderately lower tumor-to-blood ratios.

Endothelium-dependent sensory non-adrenergic non-cholinergic vasodilatation in rat thoracic aorta: involvement of ATP and a role for NO

The involvement of non-adrenergic non-cholinergic (NANC) transmitters, such as adenosine 5'-triphosphate (ATP) and nitric oxide (NO), in the neurogenic relaxation of rat thoracic aorta was investigated in vessel segments suspended for isometric tension recording by polygraph. Responses to electrical field stimulation (EFS) and exogenous vasodilator were investigated in vessels precontracted with 5-hydroxytryptamine. EFS (100 V, 2-16 Hz, for 10 s at 3-min intervals), in the presence of guanethidine (10 microM) and atropine (10 microM) produced frequency-dependent relaxations. Pretreatment with tetrodotoxin (1 microM) markedly reduced the relaxation and desensitization with capsaicin (10 microM) significantly inhibited the relaxation. Exogenously added ATP caused concentration-dependent relaxations. Mechanical removal of the endothelium significantly inhibited EFS- and ATP-induced relaxation by 30+/-3% and 37+/-2%, respectively. Pretreatment with a P1-purinoceptor antagonist, 8-phenyltheophylline (10 microM) or P2X-purinoceptor antagonist, Evans blue (10 microM) did not influence the relaxations to EFS and exogenously added ATP. In contrast, the P2Y-purinoceptor antagonist, basilen blue (100 microM) markedly reduced the relaxations to EFS by 52+/-4% in the endothelium-intact preparations. However, in the endothelium-denuded preparations and capsaicin-pretreated preparations, basilen blue did not change relaxations elicited by EFS. The NO synthase inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME, 100 microM) also significantly inhibited the relaxations to EFS and ATP by 40+/-6% and 30+/-2%, respectively, in the endothelium-intact preparations but had no effect on the relaxations in the endothelium-denuded preparations or capsaicin-pretreated preparations. In addition, the EFS-induced relaxations were also inhibited 43+/-7% by pretreatment with 1H-[1,2,4]-oxadiazolo[4,3-alpha]quinoxalin-1-one (ODQ; 1 microM), soluble guanylate cyclase inhibitor. This study suggests that the NANC nerve system is present in the thoracic aorta of rat, mediating vasodilatation by sensory nerves. ATP, as a neurotransmitter released from sensory nerves, activates P2Y-purinoceptors located on the endothelium and stimulates the NO/cyclic GMP pathway, resulting in vasodilatation.

Synergistic effect of angiotensin-converting enzyme and angiotensinogen gene on cardiac hypertrophy

AIMS

There are controversies concerning the association of angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism with left ventricular hypertrophy (LVH), and the unclear association between angiotensinogen (ATG) M235T polymorphism and LVH. We investigated both the separate and interactive effects of these two genes on LVH in patients (N=396) with cardiovascular disease and normal healthy volunteers (N=133).

RESULTS

Frequency of DD genotype of ACE gene was significantly (P<0.05) higher in patients with LVH than patients without LVH or normal controls. Frequency of IT genotype of ATG gene in patients with LVH was significantly (P<0.01) greater than that in normal controls or marginally (P=0.1) higher than that in patients without LVH. These findings were also observed in normotensive patients and normal controls after excluding hypertensive patients. Only in patient group, the frequency of DD genotype in the highest quartile of LVMI was significantly greater than that in the lowest quartile (P<0.05). The higher tendency of TT genotype in the highest quartile patients compared with that in the lowest, did not reach statistical significance. In combined genotype analysis, there was a remarkable difference in LVMI between the two extreme double homozygotes only in patient group (156+/-25 versus 109+/-25 g/m2 for TT+DD versus MM+II) (P<0.01). In ANCOVA, the interaction term composed of ACE and ATG genotype was a significant independent variable for LVMI only in the male patient group (P<0.01).

CONCLUSION

The D-allele of ACE and T-allele of ATG gene exert a synergistic effect on cardiac hypertrophy in male patients with cardiovascular diseases, but not in normal healthy population.

Expression of the MAGE 3 gene product in squamous cell carcinomas of the head and neck

BACKGROUND

The melanoma antigen (MAGE) 3 gene may be a useful tumor specific marker since it is expressed in a variety of cancers.

MATERIALS & METHOD

The expression and intracellular location of MAGE 3 gene product were investigated in 40 squamous cell carcinomas, 2 tumor lines, 20 benign diseases, and 20 normal tissues of the head and neck. Immunohistochemical staining with anti-MAGE 3 mAb 57B was conducted from fresh frozen specimens. Correlations between MAGE 3 expression and clinicopathological parameters were also evaluated.

RESULTS

The MAGE 3 gene product was detected in squamous cell carcinomas (18/40, 45%) and in tumor cell lines (2/2, 100%), but not in benign diseases and normal tissues. No significant correlation was drawn between MAGE 3 expression and clinical parameters including clinical stages and metastasis.

CONCLUSION

These results show MAGE 3 antigen could represent a potential target for immunotherapy in head and neck squamous cell carcinomas.

Heart failure in Korean elderly patients — clinical features, prognosis and prognostic factors

Heart failure (HF) is very common in the elderly but there are not sufficient data about the clinical characteristics and prognostic factors of HF among the Asian elderly patients. The aim of the study was to find out the clinical characteristics, survival, and prognostic factors of HF in Korean elderly patients. Among elderly patients admitted from February 1995 to February 1998, the patients with a discharge diagnosis of HF were enrolled. Through the medical record review, the diagnosis was confirmed and clinical parameters to affect survival were identified. Total number of the subjects was 104 [age: 77+/-7 years (65-96), male:female=36:68, follow-up duration: 20+/-14 months, LVEF: 46+/-16%]. Ischemic heart disease (IHD) was the most common cause of HF (42%) followed by valvular heart disease (28%), and hypertension (20%). The 1-year survival rate was 71.3%. Advanced age [risk ratio (RR): 1.41 per 5 years of age; 95% CI: 1.11-1.80] and reduced left ventricular ejection fraction (0.69 per 10%, 0.52-0.93), poor initial functional class (2.40, 1.15-5.00), diabetes (2.79, 1.30-5.97) and past history of HF (2.37, 1.10-5.10) badly affected the survival rates. When the Cox proportional hazard model was applied for multivariate analysis, only aging (1.64 per 5 years of age, 1.19-2.28) and diabetes (4.92, 1.83-13.23) predicted poor prognosis. Twenty-seven percent of the patients had diastolic HF (LVEF>45%, LVEDD<55 mm) who had higher survival rates with marginal significance (0.35, 0.10-1.17, P=0.09).

Variant angina is not associated with angiotensin I converting enzyme gene polymorphism but rather with smoking

BACKGROUND

Angiotensin converting enzyme (ACE) perhaps plays roles in regulating coronary vasomotor tone by producing angiotensin II and degrading bradykinin.

OBJECTIVES

We sought to investigate the role of ACE gene polymorphism in the pathogenesis of variant angina and to compare it with that of other clinical risk factors for male patients with variant angina and age-matched and sex-matched control subjects.

METHODS

We studied 78 male patients with variant angina who exhibited spontaneous or provoked coronary spasms during coronary angiography and compared prevalences of ACE gene genotype (deletion D and insertion I) and other risk factors between this group of patients with variant angina and age-matched and sex-matched control subjects whose angiograms were normal and in whom the ergonovine test did not cause spasms (n = 80).

RESULTS

Smokers were more prevalent in the group of patients with variant angina (P < 0.05). Genotype and allele prevalences of the group of patients with variant angina (0.14, 0.53 and 0.33 for DD, DI and II and 0.41 and 0.59 for D and I, respectively) were no different from those of the control group (0.16, 0.49 and 0.35 for DD, DI and II and 0.40 and 0.60 for D and I). Multiple logistic regression analysis showed that smoking was a significant risk factor for variant angina (odds ratio 2.61, 95% confidence interval 1.03-6.66) whereas ACE genotype was not.

CONCLUSIONS

Variant angina is associated with an environmental factor, such as smoking, rather than a genetic factor, such as ACE gene polymorphism.

Topical oleo-hydrogel preparation of ketoprofen with enhanced skin permeability

In an attempt to improve the skin penetration of ketoprofen, various transdermal formulations were prepared, and their in vitro skin permeability and in vivo percutaneous absorption were evaluated. In vitro permeation studies were performed using a modified Franz cell diffusion system in which permeation parameters such as cumulative amount at 8 hr Q8hr, steady-state flux Jss, or lag time tL were determined. In the in vivo percutaneous absorption study using the hairless mouse, maximum concentration Cmax and area under the curve at 24 hr AUC24h were measured. The optimal transdermal formulation (oleo-hydrogel formulation) of ketoprofen showed a Q8hr value of 227.20 micrograms/cm2, a Jss value of 29.61 micrograms/cm2/hr, and a tL value of 0.46 hr. The Q8hr and Jss values were about 10-fold (p < .01) higher than those (Q8hr = 19.61 micrograms/cm2; Jss = 2.66 micrograms/cm2/hr) from the K-gel and about 3.5-fold (p < .01) than those (Q8hr = 60.00 micrograms/cm2; Jss = 7.99 micrograms/cm2/hr) of the K-plaster. In the in vivo percutaneous absorption, the Cmax (6.82 micrograms/ml) and AUC24h (55.74 micrograms.hr/ml) values of the optimal formulation were significantly (p < .01) higher than those of K-gel and K-plaster. The relative bioavailability of the oleo-hydrogel following transdermal administration in reference to oral administration was about 37%, and the Cmax value (4.73 micrograms/cm2) in the hypodermis following topical administration was much higher than those from the conventional products (Cmax of K-gel and K-plaster were 0.92 +/- 0.19 microgram/cm2 and 1.27 +/- 0.37 microgram/cm2, respectively). These data demonstrate that the oleo-hydrogel formulation of ketoprofen was more beneficial than conventional products (K-gel and K-plaster) in enhancing transdermal permeation and skin absorption of ketoprofen. Furthermore, there was a good correlation between in vitro permeation parameters and in vivo percutaneous absorption parameters.

Co-occurrence of Fusarium mycotoxins in mouldy and healthy corn from Korea

A total of 71 samples consisting of 36 mouldy and 35 visibly healthy corn were collected from Kangwon province of Korea and analysed for 8-ketotrichothecenes, zearalenone (ZEA), and fumonisins, including fumonisin B1 (FB1), fumonisin B2 (FB2), and fumonisin B3 (FB3). Five 8-ketotrichothecenes, namely deoxynivalenol (DON), 15-acetyldeoxynivalenol (15-ADON), 3-acetyldeoxynivalenol (3-ADON), nivalenol (NIV), and 4-acetylnivalenol (4-ANIV), ZEA, FB1, FB2, and FB3 were detected in corn samples. DON, 15-ADON, 3-ADON, NIV, 4-ANIV, ZEA, FB1, FB2, and FB3 were detected in mouldy corn with mean values of 4.0, 0.9, 0.2, 1.7, 0.4, 0.6, 23.2, 7.5, and 6.3 micrograms/g, respectively. Visibly healthy corn samples were contaminated with lower levels of 8-ketotrichothecenes, ZEA, and fumonisins than mouldy corn samples. However, 5 of 35 healthy corn samples analysed were contaminated with fumonisins at high levels up to 12.5 micrograms/g for FB1, 5.4 micrograms/g for FB2, and 0.5 microgram/g for FB3. This is the first report on the simultaneous occurrence of trichothecenes, ZEA, and fumonisins in corn from Korea.

5-azacytidine induces transgene silencing by DNA methylation in Chinese hamster cells

The cytosine analog 5-azacytidine (5-AzaC) is a demethylating agent that is also known to induce mutagenesis in mammalian cells. In this study, the mutagenic potential of this drug was tested in the G10 and G12 transgenic Chinese hamster cell lines, which have a single bacterial gpt gene integrated into the genome at different sites, with its expression driven by a simian virus 40 (SV40) promoter. We show that the mutation frequencies following a 48-h exposure to different concentrations of 5-AzaC were 10 to 20 times higher than those of any of the other numerous mutagens that have been tested in the G10-G12 system. Moreover, the mutation frequencies were much higher in the G10 cell line than in the G12 cells. Detailed molecular analysis of the 6-thioguanine (6-TG)-resistant variants demonstrated that transgene silencing by de novo DNA methylation and increased chromatin condensation in the SV40 promoter was the major factor responsible for this high level of 6-TG resistance. As would be expected, exposure to 5-AzaC lowered the overall genomic DNA methylation levels, but it unexpectedly caused hypermethylation and increased chromatin condensation of the transgene in both the G10 and G12 cell lines. These results provide the first evidence that 5-AzaC may also induce transgene-specific DNA methylation, a phenomenon that can further be used for the elucidation of the mechanism that controls silencing of foreign DNA.

Natural occurrence of the C series of fumonisins in moldy corn

We analyzed 44 moldy corn samples for the B and C series of fumonisins by high-performance liquid chromatography. Of the 44 samples, 32 (73%) were contaminated with both the B and C series of fumonisins and 6 were contaminated with only the B series of fumonisins. The incidence of fumonisin C1 in moldy corn was 71%; the incidence was 11% for fumonisin C3 and 43% for fumonisin C4. Their mean levels ranged from 500 to 1,900 ng/g. This is the first report on the natural occurrence of the C series of fumonisins and fumonisin B4 in moldy corn.

N-Acetyl derivatives of type C fumonisins produced by fusarium oxysporum

Four new fumonisins, an isomer of fumonisin C1 (iso-FC1) (1) and three N-acetyl derivatives of hydroxylated fumonisin C1 (OH-FC1) (2), fumonisin C1 (FC1) (3), and iso-FC1 (4) were isolated from wheat cultures of Fusarium oxysporum. One of the hydroxy groups of compound 1 is at C-3 instead of C-4 for FC1. Compounds 2-4 are similar in structure to OH-FC1, FC1, and iso-FC1, respectively, except for the presence of an acetyl group at the amine of C-1.

Estimation of left ventricular end-diastolic pressure with the difference in pulmonary venous and mitral A durations is limited when mitral E and A waves are overlapped

Previous studies showed that difference in pulmonary venous and mitral A-wave durations can be used for the estimation of left ventricular end-diastolic pressure, which is based on the assumption that the pulmonary venous A wave and mitral A wave start with the beginning of left atrial contraction. It is also assumed that the mitral A wave ends with the end of left atrial contraction. These assumptions may not be correct if left atrial contraction occurs before the early left ventricular filling is completed. Adequate Doppler mitral inflow and pulmonary venous flow signals were obtained simultaneously with left ventricular pressures at the cardiac catheterization laboratory in 50 patients who showed separated E and A waves in mitral inflow. After heart rate was increased by right atrial pacing to make the mitral E and A waves overlap, Doppler and hemodynamic measurements were repeated. When E and A waves are separated, pulmonary A-wave duration exceeding mitral A-wave duration has a sensitivity of 67% and specificity of 85% in the prediction of elevated left ventricular end-diastolic pressure (>/=20 mm Hg), whereas the pulmonary A wave ending later than mitral A wave has a sensitivity of 83% and a specificity of 45%. When the mitral E and A waves are overlapped, the pulmonary A wave ending later than mitral A wave is better for the prediction of elevated left ventricular end-diastolic pressure (sensitivity 55%, specificity 75%) than pulmonary A-wave duration exceeding mitral A-wave duration (sensitivity 9%, specificity 96%). However, overall, both methods are limited for clinical use.

A hemorrhagic factor (Apicidin) produced by toxic Fusarium isolates from soybean seeds

Fifty-two isolates of Fusarium species were obtained from soybean seeds from various parts of Korea and identified as Fusarium oxysporum, F. moniliforme, F. semitectum, F. solani, F. graminearum, or F. lateritium. These isolates were grown on autoclaved wheat grains and examined for toxicity in a rat-feeding test. Nine cultures were toxic to rats. One of these, a culture of Fusarium sp. strain KCTC 16677, produced apicidin, an antiprotozoal agent that caused toxic effects in rats (including body weight loss; hemorrhage in the stomach, intestines, and bladder; and finally death) when rats were fed diets supplemented with 0.05 and 0.1% apicidin. The toxin was toxic to brine shrimp (the 50% lethal concentration was 40 microg/ml) and was weakly cytotoxic to human and mouse tumor cell lines.

Pulsed Doppler ultrasonographic evaluation of portal blood flow in dogs with experimental portal vein branch ligation

Portal blood flow was measured using pulsed Doppler ultrasound in 6 dogs before and after left portal vein branch ligation. Mean portal vein blood flow velocity and mean portal vein blood flow were significantly reduced after ligation and the congestion index was increased (p < 0.01). Pulsed Doppler ultrasound studies provide valuable physiological information which may assist the clinician with the diagnosis of canine hepatic circulatory disorders.

Down-regulation of protein kinase C: a potential mechanism for 2-amino-3-methylimidazo[4,5-f]quinoline-mediated immunosuppression

Immunosuppressive mechanism of food-born mutagenic and carcinogenic heterocyclic amine, 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), was studied in murine spleen cells. IQ suppressed the IL-2 secretion and its mRNA expression. Treatment of IQ also decreased PKC activity in both the membrane fraction and the cytosol fraction. Treatment of PMA resulted in the recovery of IQ-induced suppression of IL-2 production, but the addition of ionomycin (Io) had no effect. Subsequently, we examined the effect of IQ on the activation of NF-kappaB, AP-1, and NF-AT, which are key transcription factors for IL-2 transcription. The activation of NF-kappaB and AP-1 was markedly inhibited by IQ in PMA/PHA-stimulated cells. Meanwhile, NF-AT was not affected by IQ in PMA/Io-stimulated cells. These results suggest that the immunosuppression induced by IQ might be associated with the down-regulation of PKC and subsequent blockade of the activation of NF-kappaB and AP-1 in the IL-2 gene expression.

Protective effects of diallyl sulfide on N-nitrosodimethylamine-induced immunosuppression in mice

Diallyl sulfide (DAS), a flavor component of garlic that has been used as a food additive, exerts chemopreventive effects at several organ sites in rodents after administration of chemical carcinogens possibly by inhibiting carcinogen activation via cytochrome P450-mediated oxidative metabolism. In this study, we investigated the protective effect of DAS on the N-nitrosodimethylamine (NDMA)-induced immunosuppression of humoral and cellular responses in BALB/c mice and the possible mechanisms involved in this protection. We observed that oral administration of DAS prior to NDMA treatment for 14 consecutive days blocked the NDMA-induced suppression of the antibody response to a T-cell-dependent antigen, sheep erythrocytes, and the lymphoproliferative response to the T-cell and the B-cell mitogens in dose-dependent manners. Treatment of mice with DAS resulted in a significant decrease of cytochrome P450 2E1-dependent p-nitrophenol hydroxylase and NDMA demethylase activities. The results show that the protective effects of DAS against the NDMA-induced immunotoxicity may, at least in part, be due to its ability to block bioactivation of NDMA mainly by the inhibition of cytochrome P450 2E1.

Restoration of atrial mechanical function after maze operation in patients with structural heart disease

BACKGROUND

The maze operation is effective for the restoration of sinus rhythm; however, restoration of atrial mechanical function has not been demonstrated in all patients.

METHODS

Maze operations were performed in 32 patients (13 men, 19 women; mean age 47.1 +/- 9.0 years) combined with valvular surgery (n = 25), coronary artery bypass graft (CABG) (n = 3), and others (n = 4). At 1 week, 3 months, 6 months, and 1 year after the operation, prospective serial Doppler echocardiographic examination was carried out to determine the presence of atrial mechanical function.

RESULTS

Sinus rhythm was restored and maintained during the follow-up period in 26 (81%) patients; in 22 patients this was due solely to the operation, whereas in four patients an antiarrhythmic agent was needed to maintain sinus rhythm. Another four patients showed paroxysmal atrial fibrillation (AF) despite treatment with an antiarrhythmic agent. Right atrial mechanical function was restored in all 30 patients with sinus rhythm or paroxysmal AF; in 19 (63%) of these, left atrial mechanical function was restored. In patients with restored left atrial mechanical function, peak A velocity (A) and A/E ratio (A/E) of mitral inflow were significantly lower than in the 16 postoperative control patients (A: 0.46 +/- 0.14 m/sec vs 0. 75 +/- 0.29 m/sec, p < 0.01; A/E: 0.40 vs 0.80, p < 0.01). In patients with left atrial mechanical function, the duration of AF was significantly shorter than in patients without left atrial mechanical function (1.9 +/- 2.9 years vs 7.1 +/- 3.0 years, p < 0. 01), but there were no significant differences in left atrial size and volume.

CONCLUSIONS

The maze operation could be safely added to standard open heart surgery for the correction of underlying structural heart disease. The rate of conversion to sinus rhythm resulting solely from the operation might be lower than the rates previously reported with only the duration of AF adversely affecting the restoration of left atrial mechanical function. Considering the fact that not all patients converted to sinus rhythm show atrial mechanical function, the role of the maze operation in the prevention of systemic embolism, with subsequent improvement in survival, requires further study.

Induction of quinone reductase by a methanol extract of Scutellaria baicalensis and its flavonoids in murine Hepa 1c1c7 cells

The effect of extracts of scutellariae radix (Scutellaria baicalensis Georgi) and its flavonoids, baicalin, baicalein and wogonin, on induction of quinone reductase (QR) in the Hepa 1c1c7 murine hepatoma cell line was examined. A significant and dose-dependent induction of QR activity was observed in the methanol extract of scutellariae radix and baicalin. HPCL analysis showed that baicalin was contained as a main component in the methanol extract of scutellariae radix, indicating that baicalin may be the major active principle of QR induction mediated by scutellariae radix extract. To elucidate the mechanism of baicalin-mediated induction of QR enzyme activity, the effect on QR mRNA levels in Hepa 1c1c7 cell cultures was investigated. Using reverse transcriptase-polymerase chain reaction techniques, time- and dose-dependent induction of QR mRNA levels by baicalin were demonstrated in Hepa 1c1c7 cells. On the basis of these results, the scutellariae radix extract or baicalin can be regarded as a readily available, promising, novel cancer chemopreventive agent.

Phytotoxicity and cytotoxicity of the fumonisin C and P series of mycotoxins from Fusarium spp. fungi

Fumonisin C (FC) and P (FP) are two recently identified series of sphingosine-analog mycotoxins, for which biological activities have not previously been reported. FC1, FC2 and OH-FC1 (1 microM) exhibited strong phytotoxicity comparable to the standard FB1 in duckweed (Lemna pausicotata L.) cultures, whereas FC3 and FC4 were moderately phytotoxic. Conversely, FP1 exhibited weak phytotoxicity only at higher concentrations (> or =10 microM). These mycotoxins exhibited a similar pattern of cytotoxicity with FB1-sensitive cultured mammalian cell lines, H4TG and MDCK.

Re-expression of differentiated proteoglycan phenotype by dedifferentiated human chondrocytes during culture in alginate beads

The proteoglycans (PGs) synthesised by normal human articular chondrocytes and a chondrocyte cell line cultured in monolayer and alginate beads were compared. Chondrocytes became dedifferentiated after serial subcultures in monolayer, exhibited a fibroblastic morphology and synthesised a large proportion of lower molecular weight, dermatan sulphate containing PGs. When transferred into alginate beads, the cells quickly regained their spherical shape and actively incorporated [3H]thymidine and [35S]sulphate during 70 days of culture. This resulted in a continuous increase in their DNA content and a rapid deposition of PGs for the first 25 days of culture, which then remained stable. Immediately after dedifferentiated chondrocytes were encapsulated into alginate beads, they began to synthesise a population of PGs with normal monomer size and an increased ability to form aggregates. The monomer size of newly synthesised PGs remained unchanged during extended periods of culture, but their ability to form aggregates and the ratios of chondroitin-6-sulphate to chondroitin-4-sulphate in their glycosaminoglycan chains gradually increased for the first 25 days before reaching normal values. Parallel experiments with HCS-2/8 cells, derived from a human chondrosarcoma, showed that they followed a similar pattern of development in alginate culture. The ability of their newly synthesised PGs to form aggregates increased with time and their sulphation pattern also gradually became normal. These results showed that culture in alginate promoted redifferentiation of dedifferentiated articular chondrocytes and assisted differentiation of HCS-2/8 chondrocytes. However, complete redifferentiation took a period of several weeks, after which synthesis of normal aggregating PGs was maintained.

Effect of red ginseng on blood pressure in patients with essential hypertension and white coat hypertension

The objective of this study is to evaluate the changes of diurnal blood pressure pattern after 8 weeks of red ginseng medication (4.5 g/day) by 24 hour ambulatory blood pressure monitoring. In 26 subjects with essential hypertension, 24 hour mean systolic blood pressure decreased significantly (p = 0.03) while diastolic blood pressure only showed a tendency of decline (p = 0.17). The decrease in pressures were observed at daytime (8 A.M.-6 P.M.) and dawn (5 A.M.-7 A.M.). In 8 subjects with white coat hypertension, no significant blood pressure change was observed. We suggest that red ginseng might be useful as a relatively safe medication adjuvant to current antihypertensive medications.

The phenolic recognition profiles of the Agrobacterium tumefaciens VirA protein are broadened by a high level of the sugar binding protein ChvE

The formation of crown gall tumors by Agrobacterium tumefaciens requires that the virulence (vir) genes be induced by chemical signals which consist of specific phenolic compounds and monosaccharides, synthesized at plant wound sites. Signal transduction in the activation of these genes is mediated by the VirA-VirG two-component regulatory system, together with ChvE, a glucose-galactose binding protein which interacts with VirA. We have previously presented genetic evidence that virA senses phenolic compounds directly (Y.-W. Lee, S. Jin, W.-S. Sim, and E. W. Nester, Proc. Natl. Acad. Sci. USA 92:12245-12249, 1995). The vir genes of strain KU12 can be induced by 4-hydroxyacetophenone, p-coumaric acid, and phenol, whereas these same phenolic compounds are weak inducers of the vir genes of strain A6. In this report, we show that a specific inducing sugar can broaden the specificity of the phenolic compound which VirA senses. 4-Hydroxyacetophenone and other related phenolic compounds function as inducing phenolic compounds with the virA gene of A6 if arabinose replaces glucose as the inducing sugar. We further demonstrate that this broadened specificity for phenolic inducers results from the increased level of ChvE through induction by arabinose via the regulatory protein GbpR. If high levels of ChvE are present, then poorly inducing phenolic compounds can induce the vir genes to high levels in combination with glucose. Comparing the induction response of the wild type and that of a VirA mutant with a mutation in its receiver domain revealed that the activity of the receiver domain is controlled by the periplasmic domain. We discuss these observations in terms of how VirA senses and transduces signals elicited by the two classes of plant signal molecules.

Anticardiolipin and anti-beta2-glycoprotein I antibodies in Behcet's disease

To investigate prevalence of anticardiolipin antibodies (aCL) in patients with Behcet's disease (BD) and to determine whether they are related to anti-beta2-glycoprotein I antibodies (aGPI), we measured aCL and aGPI in 47 patients of BD and 14 patients of systemic lupus erythematosus (SLE). The levels of aCL and aGPI were determined by conventional enzyme immunoassay for both IgG and IgM classes. Twelve (25.5%) patients with BD were positive for IgG or IgM aCL and no patient was positive for aGPI. Eleven (78.6%) patients with SLE were also positive for aCL and among them, 8 (72.7%) patients were positive for aGPI. Positive IgG aCL patients with BD showed lower level of IgG aCL than those with SLE (15.7+/-7.3 vs 34.1+/-16.0 GPL, p<0.05). There was no relation between the presence of aCL in BD and either dinical activity or clinical features. In the patients with BD, aCL are found but it would not be associated with aGPI as they are in patients with SLE. In patients with BD, aCL seem to be authentic aCL unlike those in patients with SLE and may not be related with vascular complications in BD.

Effects of nickel on DNA methyltransferase activity and genomic DNA methylation levels

Methylation of DNA plays an important role in organizing the genome into transcriptionally active and inactive zones. Nickel compounds cause chromatin condensation and DNA methylation in the transgenic gpt+ Chinese hamster cell line (G12). Here we show that nickel is an inhibitor of cytosine 5-methyltransferase activity in vivo and in vitro. In living cells, this inhibition is transient and following a recovery period after nickel treatment, Mtase activity slightly rebounds. Genomic DNA methylation levels are also somewhat decreased following nickel treatment, but with time, there is an elevation of total DNA methylation above basal levels and before any rebound of methyltransferase activity. These results suggest that nickel exposure can elevate total genomic DNA methylation levels even when DNA methyltransferase activity is depressed. These findings may explain the hypermethylation of senescence and tumor suppressor genes found during nickel carcinogenesis and support the model of a direct effect of Ni2+ on chromatin leading to de novo DNA methylation.

Inhibition of NF-kappa B/Rel nuclear translocation by dexamethasone: mechanism for the inhibition of iNOS gene expression

The decrease in NO production was found to correlate well with a decrease in inducible nitric oxide synthase (iNOS) mRNA expression as demonstrated by Northern blot analysis and quantitative RT-PCR. Since the promoter in iNOS gene contains binding motifs for NF-kappa B/Rel, NF-IL6, and Oct which appear to be important for LPS-mediated iNOS induction, the effects of DEX on the activation of these transcription factors were examined. Treatment of DEX to RAW 264.7 cells induced a dose-related inhibition of NF-kappa B/Rel in chloramphenicol acetyltransferase activity, while NF-IL6 or Oct activation was not affected by DEX. Treatment of RAW 264.7 cells with DEX inhibited DNA binding of NF-kappa B/Rel proteins to their cognate DNA site as measured by electrophoretic mobility shift assay. In addition, DEX treatment caused a significant reduction in nuclear c-rel, p65, and p50 protein contents, and these decreases were paralleled by the accumulation of cytoplasmic c-rel, p65, and p50. These results suggest that DEX may inhibit iNOS gene expression by a mechanism involving the blockade of LPS-induced nuclear translocation of NF-kappa B/Rel.

Characterization of an unusual sensor gene (virA) of Agrobacterium

Previous studies have shown that the virulence(vir) genes of Agrobacterium tumefaciens strain KU12 are induced by a unique set of phenolic compounds that are non-functional in most strains of Agrobacterium. Further, strain KU12 is not induced by phenolic compounds that induce the vir genes in other strains. Previous studies have shown that these differences in inducing activity result from differences in the sensor protein for these signal molecules, the VirA protein. To gain some understanding of the basis for these differences in sensing ability, we sequenced the entire virA locus of pTiKU12, including its promoter region and compared this sequence with five different published virA sequences that respond in different ways to inducing compounds. The virA gene of KU12 is composed of an open single reading frame coding for 851 aa. At the aa level, the VirA protein of pTiKU12 is 45, 45, 49, 49 and 64% identical to the VirA proteins from pTiA6, pTi15955, pRiA4, pTiC58 and pTiAg162, respectively. The transcription start sites of pTiKU12 and pTiA6 virA genes differ significantly when mapped by primer extension. Unlike all other vir genes, except the virA gene of pTiAg162, pTiKU12 virA is constitutively expressed, and its synthesis is not induced by phenolic compounds. The lack of induction is accounted for by the fact that the promoter region does not have the conserved VirG-binding dodecadeoxynucleotide sequence (vir-box) that was previously identified in all promoter regions of inducible vir genes.

Cloning of Novel Maltooligosaccharide-Producing Amylases as Antistaling Agents for Bread

For better understanding of the antistaling effect of starch-hydrolyzing enzymes, maltose-, maltotriose-, or maltotetraose-producing enzymes were applied to bread mix and the retrogradation rate of the bread was determined using differential scanning calorimetry. A new amylase isolated from Bacillus subtilis SUH 4-2, which selectively produces maltose and maltotriose from starch solution (amylase II), and another amylase from Streptomyces albus KSM-35, mainly producing maltotetraose and maltotriose (amylase IV), were cloned, characterized, and evaluated as antistaling agents for bread. Addition of amylase II or amylase IV significantly reduced the bread staling rate during 7 days of storage (p < 0.05), and especially amylase IV was as effective as a commercial enzyme, Novamyl. Analyses of the maltooligosaccharide composition of bread suggest that maltotriose and maltotetraose produced by the enzyme reaction are responsible for retarding bread retrogradation.

Reciprocal change in angiotensinogen mRNA expression in rat myocardium and liver after myocardial infarction

The aim of this study was to analyze sequential change of angiotensinogen (Ao) mRNA expression in rat liver and noninfarcted myocardium after myocardial infarction (MI). Female sprague-Dawley rats were subjected either to left coronary artery occlusion or sham operation. Three weeks after MI, coronary artery ligation resulted in comparable infarct sizes. A hypokinetic thin anterior wall and remarkable dilatation of the left ventricle, as well as decreased contractility (left ventricular end-systolic dimension = 6.0+/-0.4, 3.3+/-0.2, LV end-diastolic dimension = 7.9+/-0.3, 5.9+/-0.2 mm, and fractional shortening = 25.3+/-3.1%, 45.1+/-3.3%) were shown in the MI and sham group, respectively, by echocardiography (P < 0.01). Experimental MI caused a significant fall in systolic blood pressure (MI 90+/-5.0, vs sham 130+/-7.5 mmHg; P< 0.01) and significantly higher left ventricular end-diastolic pressure (MI 21+/-1.5, vs sham 11+/-1.0 mmHg: P < 0.01). At 4, 18, and 24h after MI, liver Ao mRNA levels, as shown by Northern blot analysis, had increased by up to four times (Ao/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) = 1.4+/-0.1 and 6.0+/-0.2 at baseline and 4h after MI, respectively (P < 0.01). After sham surgery, however, the corresponding increase was slight (maximal 1.5-fold). Three days after MI, liver mRNA had returned to the baseline level. In contrast, ATG mRNA expression in noninfarcted myocardium, as shown by reverse transcription-polymerase chain reaction and Southern blotting, decreased transiently during the acute phase. It returned to its baseline level within 3 days, and then increased further (Ao/ GAPDH = 2.9+/-0.6, 0.3+/-0.1, 3.2+/-0.8, and 3.7+/-0.8 at baseline, 24h, 3 days, and 3 weeks after MI, respectively). In conclusion, it can be stated that after MI, the Ao gene contributes, acutely in the liver and chronically in the myocardium, to the maintenance of hemodynamic homeostasis during the acute phase and ventricular remodeling during the chronic phase.

Vitamin C supplementation restores the impaired vitamin E status of guinea pigs fed oxidized frying oil

To investigate the effect of dietary oxidized frying oil (OFO) on tissue retention of vitamin C, and to explore the effect of vitamin C supplementation on tissue vitamin E concentrations and lipid peroxidation, male weanling guinea pigs were divided into four groups. Guinea pigs were fed 15% OFO diets supplemented with vitamin C at 300, 600 or 1500 mg/kg diet. Control animals were fed a diet containing 15% fresh untreated soybean oil with 300 mg/kg of vitamin C. After 60 d of feeding, body weight gain, food intake, feed efficiency and plasma triglyceride concentration were significantly lower in guinea pigs fed OFO diets than in controls (P < 0.05). However, plasma cholesterol concentration was highest in guinea pigs fed the OFO diet supplemented with 300 mg/kg vitamin C. Increasing vitamin C in OFO diets significantly reduced plasma cholesterol concentration. Plasma and tissue vitamins C and E concentrations were significantly lower in the OFO-fed guinea pigs receiving 300 mg/kg vitamin C than in controls. Greater levels of supplemental vitamin C increased tissue vitamins C and E. Guinea pigs fed OFO diets had significantly higher tissue levels of thiobarbituric acid reactive substances (TBARS) (P < 0.05) than controls. Our results demonstrated that OFO feeding, which impaired alpha-tocopherol retention and increased TBARS, could be alleviated somewhat by vitamin C supplementation.

Cyclic AMP Restores Appressorium Formation Inhibited by Polyamines in Magnaporthe grisea

ABSTRACT Magnaporthe grisea, the causal agent of rice blast, forms a dome-shaped melanized infection structure, an appressorium, to infect its host. Environmental cues that induce appressorium formation in this fungus include the hydrophobicity and hardness of the contact surface and chemicals produced by the host. An elevated concentration of intracellular cyclic AMP (cAMP) has been implicated in appressorium differentiation in M. grisea. Polyamines (putrescine, spermidine, and sper-mine) are involved in cell growth and differentiation in a wide range of organisms. To understand the role of polyamines in appressorium differentiation in M. grisea, intracellular polyamines were quantified, and the effects of polyamines and polyamine biosynthesis inhibitors on conidial germination and appressorium formation were tested. High levels of polyamines were detected in freshly collected spores, but the levels decreased during conidial germination. Spermidine was found to be the major component. Polyamines and polyamine biosynthesis inhibitors did not affect conidial germination, but polyamines specifically impaired appressorium formation. Furthermore, exogenous addition of cAMP restored appressorium formation inhibited by poly-amines. These results suggest that polyamines may reduce intracellular cAMP levels in M. grisea, leading to the inhibition of appressorium formation.

Neural solution to the correction of miss distance in gun fire control system

Multilayer perceptrons trained with the backpropagation algorithm are tested in gun fire control system for error correction and are compared to optimal algorithms based on minimum mean square error. The structure of the proposed neural controller is described and performance results are shown.

Noncollimated bidirectional shearing interferometer for measuring a long radius of curvature

A method for measuring a long radius of curvature with a modified half-aperture bidirectional shearing interferometer is described. A plane mirror of the interferometer is replaced with a test mirror, and the incident beam is decollimated by shifting of the source to equalize the widths of the bidirectional shearing fringes reflected from the plane and test mirrors. This method can be applied to concave and convex surfaces.