High body mass index and dietary pattern are associated with childhood asthma

The increasing prevalence of asthma has coincided with an increase of body mass index (BMI) in both children and adults. We investigated the relationship between BMI and the symptom prevalence of asthma and the possible influences of dietary pattern. This was a community-based, cross-sectional study of 24,260 school children aged 6-12 years. Prevalences of asthma and potential confounding factors were assessed using a Korean version of the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire which was completed by parents. We analyzed the relationship between BMI and symptoms of asthma and the possible influences of dietary pattern. A significant positive association between high BMI and previous 12-month prevalence of wheeze remained in boys (adjusted odds ratio, 1.610; 95% confidence interval, 1.274-2.033) but not in girls. In addition, there were significant associations between high BMI and lifetime prevalence of wheeze, previous 12-month wheeze, exercise-induced wheeze, diagnosis, and treatment of asthma. There were significant associations between high BMI and previous 12-month wheeze regardless of breast-milk feeding or whole-milk feeding. Frequent intake of fresh seafood, fresh fruits, and vegetables was associated with reduced prevalence of current asthma symptoms and was also associated with decreased BMI. These results indicate that BMI may be an independent risk factor for the development of asthma symptoms in boys. Intake of fresh seafood, fresh fruit, and vegetables, which may be associated with decreased BMI, may contribute to protect against the development of asthma symptoms in Korean elementary schoolchildren.

Oxidative stress during peritoneal dialysis: implications in functional and structural changes in the membrane

Progressive peritoneal fibrosis, membrane hyperpermeability, and ultrafiltration failure have been observed in patients on long-term peritoneal dialysis (PD). The present study tested the hypothesis that reactive oxygen species (ROS) generated by conventional PD solution (PDS) mediate functional and structural alterations of peritoneal membrane in vivo. Sprague-Dawley rats were randomized to control, PDS, PDS with an antioxidant, and PDS with an angiotensin II (Ang II) receptor blocker. Commercial PDS containing 3.86% glucose (20-30 ml) with or without N-acetylcystein (NAC) 10 mM or losartan 5 mg/kg was administered intraperitoneally twice a day for 12 weeks. Control rats received sham injection. Rats treated with PDS had significantly lower drain volume and D(4)/D(0) glucose, but higher D(4)/P(4) creatinine and increased membrane thickness and endothelial NOS (eNOS) expression compared to control rats. Omental transforming growth factor (TGF)-beta1, vascular endothelial growth factor (VEGF), collagen I, and heat-shock protein (hsp) 47 expression and lipid peroxide levels and dialysate VEGF and Ang II concentrations were significantly increased in rats treated with PDS compared to control. All of these changes were prevented by both NAC and losartan. In conclusion, the present study demonstrates that ROS generated by conventional PDS are, in large part, responsible for peritoneal fibrosis and membrane hyperpermeability. We suggest that antioxidants or Ang II receptor blockers may allow better preservation of the structural and functional integrity of the peritoneal membrane during long-term PD.

An open-label study of escitalopram (Lexapro) for the treatment of 'Depression of Alzheimer's disease' (dAD)

BACKGROUND

Depression is a frequent neuropsychiatric complication of Alzheimer's Disease.

METHODS

This study investigated the safety and effectiveness of escitalopram (LEXAPRO) for depression in AD (dAD) as defined by the NIMH consensus criteria in an 8-week, open-label treatment study.

CONCLUSION

Escitalopram was efficacious and safe for the treatment of dAD in this study. Larger, controlled studies are warranted to further assess the efficacy for mood and behavioral disturbances in this medically fragile population.

Activity of some aminoglycoside antibiotics against true fungi, Phytophthora and Pythium species

AIMS

To investigate the in vitro antifungal and antioomycete activities of some aminoglycosides against true fungi and Phytophthora and Pythium species and to evaluate the potential of the antibiotics against Phytophthora late blight on plants.

METHODS AND RESULTS

Antifungal and antioomycete activities of aminoglycoside antibiotics (neomycin, paromomycin, ribostamycin and streptomycin) and a paromomycin-producing strain (Streptomyces sp. AMG-P1) against Phytophthora and Pythium species and 10 common fungi were measured in potato dextrose broth (PDB) and on seedlings in pots. Paromomycin was the most active against Phytophthora and Pythium species with a minimal inhibitory concentration of 1-10 microg ml(-1) in PDB, but displayed low to moderate activities towards other common fungi at the same concentration. Paromomycin also showed potent in vivo activity against red pepper and tomato late blight diseases with 80 and 99% control value, respectively, at 100 microg ml(-1). In addition, culture broth of Streptomyces sp. AMG-P1 as a paromomycin producer exhibited high in vivo activity against late blight at 500 microg freeze-dried weight per millilitre.

CONCLUSIONS

Among tested aminoglycoside antibiotics, paromomycin was the most active against oomycetes both in vitro and in vivo.

SIGNIFICANCE AND IMPACT OF THE STUDY

Data from this study show that aminoglycoside antibiotics have in vitro and in vivo activities against oomycetes, suggesting that Streptomyces sp. AMG-P1 may be used as a biocontrol agent against oomycete diseases.

p53 Status does not affect photodynamic cell killing induced by hypericin

PURPOSE

Given that p53 is a tumor suppressor that plays a central role in the cellular response to DNA damage and that more than 50% of all cancers have mutated p53, the wider utility of photodynamic therapy (PDT) in the treatment of cancer will depend on an understanding of whether p53 status modulates response to PDT. In this study, we investigated the photosensitivity of isogenic cell lines that differ only in their p53 status to PDT using hypericin as the photosensitizer.

METHODS

Acute (MTT) and chronic (clonogenic) cytotoxic assays were performed on two osteosarcoma cell-lines (U2OS and U2OS+p53DD) that are isogenic except that the latter expresses dominant negative p53. The inducible expression of p53 was determined on western blots. Uptake of hypericin, cell cycle profile analysis, measurement of membrane phosphatidylserine externalization and changes in mitochondrial membrane potential were investigated using flow cytometry.

RESULTS

Hypericin uptake was observed to be equivalent in U2OS and U2OS+p53DD cells. There were no significant differences in cell killing between these cell-lines in both the MTT and clonogenic assays (IC(50) of 0.4 microg/ml from MTT assay). p53 expression did not increase up to 24 h after PDT treatment in both cell lines. There were also no significant differences in the cell-cycle arrest profiles and timing of onset of apoptosis.

CONCLUSIONS

Taken together, these results suggest that the status of p53 may not be important in PDT-mediated cell killing or induction of apoptosis. By extension, these results imply that PDT may be used with equal efficacy for the treatment of p53-positive and -negative tumors.

Urine leukotriene E and eosinophil cationic protein in nasopharyngeal aspiration from young wheezy children

Respiratory syncytial virus (RSV) infection is a risk factor for the development of asthma. It is very hard to distinguish bronchiolitis with respiratory virus infection from allergic asthma at first wheezing attack in early childhood. To distinguish wheezing children with RSV bronchiolitis from asthmatic children, we measured leukotriene E(4)(LTE(4)) in urine and ECP in nasopharyngeal aspiration (NPA) at first day of admission with wheezing attack. Thirty-two non-atopic children younger than the age of 3 yr with RSV induced bronchiolitis, 35 atopic asthmatic children with/without respiratory viral infection, and 23 children who exhibited no evidence of atopy, asthma, or virus infections as controls were selected in this study. We measured urinary LTE(4) and ECP level in NPA from subjects. Urinary LTE(4) concentrations in children with asthma were significantly higher than urinary LTE(4) in bronchiolitis and in controls (240.8 +/- 129.8 vs. 162.8 +/- 73.9 vs. 85.1 +/- 31.6 pg/ml). Children with RSV infection demonstrated higher urinary LTE(4) levels compared to children without RSV infection among asthmatic children. ECP in NPA was significantly correlated with urinary LTE(4) (r = 0.57, p < 0.01) in children entered this study who had detectable levels for both LTE(4) and ECP. In summary, Urinary LTE(4) concentrations may be suggested to useful mediators for differential diagnosis of wheezy diseases in early childhood. RSV infection also is associated with synergizing LT biosynthesis and this study demonstrated ECP in NPA was significantly correlated with urinary LTE(4) and may suggest that cysteinyl leukotriene initiate the production of ECP in early childhood, which could contribute to the development of wheeze.

A new Hypocrea strain producing harzianum A cytotoxic to tumour cell lines

AIMS

To identify a new fungal strain, Hypocrea sp. F000527 producing a trichothecene metabolite, harzianum A, and to evaluate its cytotoxicity to tumour cell lines.

METHODS AND RESULTS

A fungal strain, F000527, with cytotoxic activity was identified as a new Hypocrea strain based on morphological characteristics and internal transcribed spacers rDNA sequence data. Harzianum A was isolated from wheat bran culture by 50% acetone extraction, silica gel chromatography, Sephadex LH-20 chromatography and HPLC. The chemical structures were determined by ESI- or HRFAB-MS and (1)H and (13)C-NMR analyses. Harzianum A showed cytotoxicity to HT1080 and HeLa cell lines with IC(50) value of 0.65 and 5.07 Łg ml(-1) respectively.

CONCLUSIONS

Harzianum A with a chemical formula of C(23)H(28)O(6) was isolated from a new Hypocrea strain and showed moderate to strong cytotoxicity to human cancer cell lines.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first report of the production of cytotoxic harzianum A by a new Hypocrea strain.

Self-reported prevalence and risk factors of asthma among Korean adolescents: 5-year follow-up study, 1995-2000

OBJECTIVES

The International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires have shown that the prevalence of childhood asthma is increasing worldwide. Although Asian countries used to have lower prevalence rates of allergic disease than Western countries, this prevalence is increasing in several Asian countries. To determine whether the prevalence of childhood asthma is changing in Korean adolescents, we compared findings from nationwide cross-sectional surveys in 1995 and 2000 on populations of middle-school children using the Korean version of the ISAAC questionnaire.

METHODS

We developed Korean versions of the ISAAC written (WQ) and video (AVQ) questionnaires for allergic diseases. In 1995, the enrolled population consisted of 15,481 children, ages 12-15, and encompassing all three grades in middle school, selected from 34 schools across the nation; the response rate was 97.3%. In 2000, 15,894 children were selected from 31 of the same schools, and the response rate was 96.4%. The SAS system version 8.0 was utilized for all statistical analyses.

RESULTS

The WQ showed that the lifetime and 12-month prevalence of wheeze did not change from 1995 to 2000. While the 12-month prevalence rates of sleep disturbed by wheezing and night cough increased, the rates of severe attack of wheezing and exercise-induced wheeze did not change, over this period of time. The lifetime prevalence of asthma diagnosis, however, increased significantly, from 2.7% in 1995 to 5.3% in 2000, as did the 12-month prevalence of asthma treatment, from 1.0% in 1995 to 1.9% in 2000. The AVQ also showed increases in the lifetime and 12-month prevalence rates of wheeze at rest, exercise-induced wheeze, nocturnal wheeze, nocturnal cough, and severe wheeze over this period of time. These were especially because of significant increases in the Provincial cities of Korea. Interestingly, the 12-month prevalence of wheeze was consistently high in Cheju with low air pollution indices, whereas this rate was low in Ulsan and Ansan with very high air pollution indices. Risk factor analysis showed that body mass index (BMI), passive smoking, and living with a dog or cat, but not air pollution, were associated with higher risk of wheeze.

CONCLUSIONS

In the 5-year period from 1995 to 2000, the prevalence of asthma symptoms has increased in Korean adolescents, much of it because of increases in Provincial Centers. BMI, passive smoking, and living with a dog or cat are important risk factors. Environmental factors other than air pollution may be associated with increases in asthma, especially in Provincial Centers.

Improved production of teicoplanin using adsorbent resin in fermentations

AIMS

To use adsorbent resins in fermentations to eliminate toxic effects on growth, reduce feedback repression of production and assist in recovery of teicoplanin.

METHODS AND RESULTS

An adsorbent resin was added to the culture broth for the adsorption of teicoplanin. Amberlite XAD-16, Diaion HP-20, charcoal and silica gel were investigated as adsorbent resins. The adsorbed teicoplanin was extracted from the resin by 80% methanol after fermentation. Antibiotic activity was quantified by the disc-agar diffusion assay against Bacillus substilis, and qualitative evaluations were based on HPLC using YMC-Pack ODS-A column. Diaion HP-20 was the most effective adsorbent resin when added at a concentration of 5% (w/v) in the inoculation stage.

CONCLUSIONS

Addition of Diaion HP-20 in fermentations eliminated toxic effects on growth and reduced feedback repression of teicoplanin by adsorption. There was a 4.2-fold increase in the quantities of teicoplanin. Addition of adsorbent assisted in the recovery of teicoplanin by reducing the recovery steps.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results of this study provide useful information for the production of teicoplanin, a glycopeptide antibiotic produced by Actinoplanes teicomyceticus. Addition of adsorbent in fermentation increased productivity of teicoplanin by more than five times.

Study on in vitro release patterns of fentanyl-loaded PLGA microspheres

In order to study the development of the delivery device of long-acting local anaesthetics for post-operative analgesia and control of chronic pain of cancer patient, fentanyl loaded poly(l-lactide-co-glycolide) (PLGA, molecular weight; 5000, 8000, 20,000, and 33,000 g/mole) microspheres (FMS) were studied. FMS were prepared by an emulsion solvent-evaporation method. The influence of several preparation parameters such as initial drug loading, PLGA concentrations, emulsifier concentrations, oil phase volume and mole ratio and molecular weight has been investigated on the fentanyl release patterns. Generally, the drug showed the biphasic release patterns, with an initial diffusion followed by a lag period before the onset of the degradation phase, but there were no lag times in the device. Fentanyl was slowly released from FMS over 10 days in vitro, with a quasi-zero order property. The release rate increased with increasing drug loading as well as increasing polymer concentration with a relatively small initial burst effect. From the results, FMS may be a good formulation to deliver the anaesthesia for the treatment of chronic pain.

A bleaching herbicidal activity of methoxyhygromycin (MHM) produced by an actinomycete strain Streptomyces sp. 8E-12

AIMS

To screen bioherbicidal isolates and evaluate herbicidal activity of methoxyhygromycin (MHM) produced by Streptomyces sp. 8E-12.

METHODS AND RESULTS

Streptomyces sp. 8E-12 with herbicidal activity was selected through seed germination bioassay. An active metabolite, MHM was isolated from culture broth by carbon absorption, butanol extraction, silica gel, Sephadex LH-20 and G-10 chromatography, and preparative HPLC. The metabolite was identified by electrospray ionization mass spectra (ESI-MS) and 1H- and 13C-NMR spectral data analyses. In vivo herbicidal activity was examined against weeds and crops grown on pots.

CONCLUSIONS

Streptomyces sp. 8E-12 produced a selective herbicidal metabolite which was identified as MHM. The metabolite showed stronger in vivo activity against monocotyledonous plants than dicotyledonous plants, and caused a bleaching (albino symptom) on some weeds including Digitaria sanguinalis and Echinochloa crus-galli.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results showed that Streptomyces sp. 8E-12 produced a bioherbicidal metabolite, MHM and can be developed as a biocontrol agent (BCA) for weed control.

Microencapsulation of lipid nanoparticles containing lipophilic drug

A polymeric emulsion bead, which consists of core and capsule, was prepared. The core is composed of lipid nanoparticles containing lipophilic drug and semi-interpenetrating networks (semi-IPNs) are prepared to provide the capsule composed of sodium alginate and hydroxypropylmethyl cellulose (HPMC). The lipid nanoparticles were encapsulated into the polymeric emulsion bead with high drug loading efficiency, and lovastatin was used as a model drug. For the application as an oral drug delivery system, the enteric coating was performed with polymeric emulsion bead. The drug release pattern was controlled by the composition of capsule materials and environmental pH.

First Report of Colletotrichum destructivum on Curly Dock

Curly dock (Rumex crispus L.) is a perennial deciduous plant in the family Polygonaceae. It is widely distributed in grasslands and orchards and is an important weed that is traditionally used as a medicinal herb. During the summers of 2000 and 2001, a severe anthracnose disease was observed on leaves of mature curly dock in the foothills near the western coastal area of Muchangpo, Ungchon, the district of Chungnam in Korea. Initial symptoms usually appeared in June as a small number of slightly soaked spots on leaves. Typical symptoms, generally observed in late July and August following a long, rainy, hot period, consisted of a number of brown leaf spots that expanded and often twisted, resulting in discoloration of whole parts to blackish brown or slightly reddish brown and defoliation. A fungus, which was isolated from the leaf lesion, was identified as Colletotrichum destructivum O'Gara based on previous descriptions (1,3). The fungus was characterized by conidia, which were long, relatively narrow, and straight to slightly curved with abruptly tapered and obtuse ends, complex appressoria, and cultures with apricotto salmon-colored sectors that lacked sclerotia. Conidial size ranged from 4.0 to 6.4 μm (average 4.8) × 10 to 23 μm (average 16.5). Setae were slender and straight but frequently flexuous, subulate, brown, and variable in length. C. destructivum has a teleomorph, Glomerella glycines (Hori) Lehman & Wolf, but the species is not well known, and the connection has not been studied in detail. The isolate has been deposited in the IMI Culture Collection as isolate IMI387103. The dimensions of conidia from the isolate matched those of C. destructivum N150 (GenBank Accession No. AF325064) isolated from Nicotiana tabacum (3). C. destructivum is distinguishable from C. gloeosporioides, whose spores are short and cylindrical with obtuse apices tapering slightly to a truncate base. Pathogenicity of the isolate was determined on 5-week-old leaves of curly dock. Leaves were inoculated with a conidial suspension of the fungus (approximately 1 × 10⁶ conidia per ml), placed in a moist chamber for 3 days, and subsequently transferred to a growth chamber maintained at 25°C. Within 7 days after inoculation, symptoms appeared that were similar to those originally observed on leaflets. Uninoculated control (sprayed only with distilled water) leaves exposed to the same environmental conditions remained healthy. C. destructivum was consistently reisolated from infected leaves. C. destructivum has been reported as a pathogen on approximately 15 genera, including Medicago sativa, Trifolium spp., Cuscuta spp., and N. tabacum (1,3), and two fungal species, C. erumpens and C. rumicis-crispi, have been reported to cause anthracnose on R. crispus. To our knowledge, R. crispus represents a previously unreported host for C. destructivum causing anthracnose, although C. gloeosporioides has been reported as a pathogen of R. crispus in Korea (2). References: (1) A. P. Baxter et al. S. Afr. Tydskr. Plantk. 2:259, 1983. (2) B. S. Kim et al. Korean J. Plant Pathol. 14:358, 1998. (3) S. Shen et al. Mycol. Res. 105:1340, 2001.

Interleukin-6, interleukin-8, interleukin-11, and interferon-gamma levels in nasopharyngeal aspirates from wheezing children with respiratory syncytial virus or influenza A virus infection

The differences between respiratory syncytial virus (RSV) and influenza A virus (IFAV) in the pathogenesis of wheezing in young children have not been clearly defined. The aim of this study was to assess the contributions of RSV vs IFAV in the pathogenesis of upper airway inflammation in wheezy young children. We compared interleukin (IL)-6, IL-8, IL-11, and interferon-gamma (IFN-gamma) levels in nasopharyngeal aspirates (NPA) from non-asthmatic children with respiratory virus infections (RSV in 17 children and IFAV in 13 children), asthmatic children with viral infections (RSV in nine children, IFAV in 10 children), and 22 unaffected healthy children (controls). Levels of IL-11 in NPA from asthmatic children were significantly higher than those from non-asthmatic children with RSV infection, and RSV infection enhanced the IL-11 production in NPA significantly compared to IFAV infection. Nasopharyngeal epithelium from children with RSV infection secreted more IL-6 than that of children with IFAV infection. There was little difference in the IL-8 and IFN-gamma levels between asthmatic and non-asthmatic children with RSV or IFAV infection. In conclusion, asthma enhanced IL-11 production in RSV infection rather than IFAV infection in early childhood. There was a trend towards greater IL-6 production in RSV infection compared with IFAV infection.

First Report of Zonate Leaf Spot of Vigna vexillata var. tsusimensis Caused by Cristulariella moricola

A zonate leaf spot disease on a wild bean variety, Vigna vexillata L. var. tsusimensis Mat., occurred in the patch fields and foothills of Chungnam and Kyonggi districts in Korea during late September, October, and early November of 1999 to 2001. The zonate lesions were particularly prevalent in October following periods of heavy dew accumulation. Initial symptoms were small, circular lesions with darkbrown marginal rings that later developed into large spots with characteristic target-shaped rings. The spots were gray to bright or blackish brown, progressed rapidly, and sometimes fused together to form lesions of up to 20 mm in diameter. Sporophores on the natural host were generally hypophyllous but sometimes amphigenous, abundant on large spots, fewer on small spots, solitary, erect, easily detachable, and up to 864 μm long. The upper portion of the sporophore is considered an individual conidium and consisted of a pyramidal head that was fusiform to ventricose and cristulate, 495 to 534 μm long, and 210 to 290 μm wide at the broadest point. Branches within the pyramidal head were short and compact, and dichotomously or trichotomously branched. The central axis within the conidium was hyaline, broad, septate, tapering toward an acute apex, and sometimes constricted at the basal septum. Conidiophores were 272 to 330 μm long and up to 24 μm wide. The fungus was identified as Cristulariella moricola (Hino) Redhead based on morphological characteristics (1,2). The fungus was isolated from Vigna leaf spots, placed on 2% water agar or potato dextrose agar (PDA), and maintained on PDA amended with 2% Vigna leaf extract. For pathogenicity tests, 4- to 5-week-old leaves of V. vexillata var. tsusimensis were surface-sterilized in 1% NaOCl. Agar disks (approximately 10 mm diameter) containing mycelia of the fungus were placed on the upper leaf surface. The inoculated plants (two leaflets per plant × 2) were then sprayed with distilled water, covered with premoistened polyethylene bags, and incubated at 15 to 25°C. Within 5 days, small leaf spots appeared that were similar to those originally observed on all inoculated leaflets. Uninoculated control leaves exposed to the same environmental conditions remained healthy. C. moricola was consistently reisolated from the infected leaves. The hyphomycete fungus C. moricola has been known to cause a bull's eye or zonate leaf spot and defoliation on woody and annual plants, including at least 73 host species and 36 families distributed in the central and eastern United States and Japan (1). In Asia, the occurrence of Cristulariella spp. on several hosts has been reported only in Taiwan and Japan (3,4). No species in the genus has ever been reported from Korea. To our knowledge, V. vexillata var. tsusimensis represents a previously unreported host for C. moricola. References: (1) M. C. Niedbalski et al. Mycologia 75:988, 1983. (2) S. A. Redhead. Mycologia 71:1248, 1979. (3). H. J. Su and S. C. Leu. Plant Dis. 67:915, 1983. (4) T. Yokoyama and K. Tubaki. Trans. Mycol. Soc. Jpn. 15:189, 1974.

Characterization of compression-molded UHMWPE, PMMA and PMMA/MMA treated UHMWPE: density measurement, FTIR-ATR, and DSC

Considered one of the weak links in the total hip replacement (THR), efforts to enhance the interfacial strength between bone cement and ultra-high molecular weight polyethylene (UHMWPE) acetabular cup had been conducted in this laboratory. Following the successful demonstration of high interfacial strengths for our new acetabular component design, the nature of physical, chemical, and thermal property of the compression-molded specimens, including UHMWPE, PMMA/MMA treated UHMWPE, and PMMA has been investigated in this study. Density results from a density gradient column showed that the molding processes and conditions were adequate for complete sintering of UHMWPE and PMMA powders. FTIR-ATR results gave a direct evidence that PMMA did exist in the PMMA/MMA treated UHMWPE matrix. It also revealed a clear diffusion-related behavior across the interface. Under the high temperature and pressure, the UHMWPE powders undergo drastic changes of their morphology and crystalline structures. These changes were examined by differential scanning calorimeter (DSC) which showed a large difference in terms of % crystallinity. The percent of PMMA deposited in the treated UHMWPE was 17.8%, 18.8%, and 24.3% from the analyses of density, FTIR-ATR, and DSC, respectively. Finally, an evidence of diffusive behavior at the interface exhibited diffusion of PMMA occurring across the interfaces between the treated UHMWPE and UHMWPE or PMMA.

The effect of disodium cromoglycate, budesonide, and cyclosporin A on interleukin-4, interleukin-5, and interleukin-13 secretions in Der p I-stimulated T cells from house dust mite-sensitive atopic and nonatopic individuals

Disodium cromoglycate (DSCG), budesonide, and cyclosporin A (CsA) were the well-known immunomodulators for the allergic and immunologic diseases clinically. In this study, we evaluated the characteristics of inhibition on cytokine synthesis of Der p I-stimulated T cells by the same inhibiting concentrations of DSCG, budesonide, and CsA in house-dust mite antigen (Der p I)-specific atopic and nonatopic healthy individuals. Seven house dust mite allergen specific patients were recruited for this study. Seven healthy volunteers were included on the basis of negative allergic manifestations and low serum immunoglobulin E values. Peripheral blood mononuclear cells (PBMCs) were cultured in the presence of recombinant interleukin (rIL)-2 with or without budesonide, DSCG, CsA, and Der p I for 48 hours. Cells were stained with anti-CD4 fluorescein isothiocyanate-conjugated monoclonal antibody, and then anti-human IL-4 phycoerythrin, IL-5, or IL-13 monoclonal antibody, respectively, was added to both blocked and stained samples. Incubation of PBMC from atopics with each immunomodulator and Der p I resulted in the reduction of IL-4 secretion compared with Der p I alone stimulation. However, IL-4 secretion in PBMC from nonatopics was not reduced with DSCG and Der p I stimulation. IL-4, IL-5, and IL-13 secretions of PBMC from atopics were significantly decreased after incubation with each immunomodulator and Der p I, compared with after incubation with Der p I alone. These results might be considered to show either that DSCG has a selective inhibiting effect on cytokine production in T cells from atopics or is a weak inhibitor of cytokine secretions compared with budesonide and CsA at even strength for the inhibition of lymphocyte proliferation in normal, healthy individuals.

Quantitative analysis of fentanyl in rat plasma by gas chromatography with nitrogen-phosphorus detection

A sensitive assay method was developed to determine fentanyl, an opiate agonist, in rat plasma by gas chromatography with nitrogen-phosphorus detection. For the pretreatment of plasma samples, sodium hydroxide was added to denature protein and n-butyl chloride was used to extract fentanyl. The calibration curve was linear within the concentration range 0.5 to 50 ng/ml (r=0.9997). The limit of detection was 0.1 ng/ml, and 0.5 ng/ml could be quantified with acceptable precision. Furthermore, fentanyl could be determined in only 200 microl of rat plasma. The method has been successfully applied to an intramuscular pharmacokinetic study at a dose of 10 microg/kg. Therefore, the current method is a valuable analytical tool for investigating the pharmacokinetics of fentanyl at low clinical doses.

Comparison of bone morphogenetic protein receptors expression in the fetal and adult skin

Wounds on fetal skin can be repaired without leaving scars until the second trimester, but after this period, skin wounds leave scars as in adults. It's known that certain growth factors such as TGF-beta, and bFGF are present at a very low levels during wound repair in fetal skin. These low levels of growth factors minimize inflammatory response and fibroblast proliferation at the wound site, which in turn inhibit collagen synthesis, and thus, allows scarless wound healing. Recently bone morphogenetic proteins (BMPs), one of the TGF-beta superfamily members, have been studied in the wound healing process. According to several studies, BMPs are related to the differentiation and growth of epithelial and mesenchymal cells, but the precise functions of BMPs and of BMP receptors on skin wound healing have not been elucidated. In this study, we investigated the expression pattern of BMP receptors in fetal skin during the second trimester and in adult skin by immunohistochemical staining and RT-PCR. BMP receptors were detected on the suprabasal epithelial cells and in the hair follicles in adult skin, but were not defected in the fetal skin except for the hair follicles. This was confirmed by confirming mRNA levels of BMP receptors by RT-PCR in both adult and fetal skins. In conclusion, BMPs and BMP receptors seem to be related to fetal and adult wound healing, and low levels of BMPs and BMP receptors during the second trimester seem to contribute to scarless wound healing in the fetus, as is TGF-beta during the second trimester.

A murine model of toluene diisocyanate-induced asthma can be treated with matrix metalloproteinase inhibitor

BACKGROUND

Toluene diisocyanate (TDI) is a leading cause of occupational asthma. TDI-induced asthma is an inflammatory disease of the airways that is associated with airway remodeling. However, there are little data available on the role of matrix metalloproteinases (MMPs) in TDI-induced asthma.

OBJECTIVE

We evaluated whether MMP-9 participates in the airway inflammation in TDI-induced asthma. An additional aim of the present study was to determine whether MMP inhibitors could be effective therapeutic agents for TDI-induced asthma.

METHODS

We developed a murine model of TDI-induced asthma to examine the involvement of MMPs by performing 2 sensitizations with 3% TDI and 1 challenge with 1% TDI using ultrasonic nebulization.

RESULTS

Murine TDI-induced asthma includes findings of (1) increased inflammatory cells, including neutrophils, lymphocytes, and eosinophils; (2) histologic changes, including infiltration of inflammatory cells around bronchioles, thickened airway epithelium, and accumulation of mucus and debris in the bronchioles; (3) increased MMP-9 activity in inflammatory cells in the airway lumen; and (4) airway hyperresponsiveness. Administration of an MMP inhibitor remarkably reduced all these pathophysiologic findings.

CONCLUSION

We conclude that TDI-induced occupational asthma is associated with the induction of MMP-9 in inflammatory cells, and the inhibition of MMP-9 may be a good therapeutic strategy.

Serum levels of interleukins (IL)-4, IL-5, IL-13, and interferon-gamma in acute asthma

T-cell activation and alteration of cytokine levels are involved in the pathogenesis of bronchial asthma. However, the profile of circulating T-lymphocyte subsets and related cytokines during acute asthmatic attacks is still unclear. We hypothesized that serum levels of interleukin (IL)-4, IL-5, and IL-13 would be increased, whereas IFN-y would be decreased in acute asthma. The subjects enrolled in this study included 58 acute asthmatics, 22 asymptomatic asthmatics, and 10 healthy controls. Serum levels of IL-4, IL-5, IL-13, and IFN-gamma were measured using a sandwich enzyme-linked immunosorbent assay. We correlated serum levels of IL-4, IL-5, IL-13, and IFN-gamma with initial forced expiratory volume in 1 sec (FEV1). Compared with control subjects, acute asthmatics had significantly increased levels of circulating IL-4 (p < 0.001), IL-5 (p < 0.001), and IL-13 (p < 0.001), although the differences were of borderline significance in serum IFN-gamma (p = 0.069). There were also significant differences in the circulating levels of IL-4, IL-5, and IL-13 between acute asthmatics and asymptomatic asthmatics. There was no significant association between initial FEV1 and serum levels of IL-4 or IL-13, however, among acute asthmatics, a lower initial FEV1 was associated with higher IL-5 and/or lower IFN-gamma levels. Our results suggest that serum levels of IL-4, IL-5, and IL-13 may be elevated in acute asthma, and that higher levels of IL-5 and/or lower levels of IFN-gamma are associated with severe airway obstruction.

Oxidative stress in diabetic nephropathy: basic and clinical information

Oxidative stress has been known to play an important role in the development and progression of diabetic nephropathy, but the intracellular signal transduction pathways regulated by reactive oxygen species (ROS) have not been clearly defined. High glucose (HG) induces intracellular ROS directly via glucose metabolism and auto-oxidation and indirectly through the formation of advanced glycation end products and their receptor binding. ROS mimic the stimulatory effects of HG and upregulate transforming growth factor-beta 1, plasminogen activator inhibitor-1, and extracellular matrix (ECM) proteins by glomerular mesangial cells, thus leading to mesangial expansion. ROS activate other signaling molecules, such as protein kinase C and mitogen-activated protein kinases and transcription factors, such as nuclear factor-kappa B, activator protein-1, and specificity protein 1 leading to transcription of genes encoding cytokines, growth factors, and ECM proteins. Finally, various antioxidants inhibit mesangial cell activation by HG and ameliorate features of diabetic nephropathy. These findings qualify ROS as intracellular messengers and as integral glucose-signaling molecules in glomerular mesangial cells in diabetic nephropathy. With this new concept, ROS assume a greater importance in the pathogenesis of diabetic nephropathy. Future studies elucidating other downstream-signaling molecules activated by ROS in mesangial and other renal cells will allow us to understand the final cellular responses to HG, such as proliferation, differentiation, apoptosis, and ECM accumulation. With this new information, we should be able to develop strategies for a more rational treatment of diabetic nephropathy.

A short sequence within domain C of duck carboxypeptidase D is critical for duck hepatitis B virus binding and determines host specificity

Virus-cell surface receptor interactions are of major interest. Hepadnaviruses are a family of partially double-stranded DNA viruses with liver tropism and a narrow host range of susceptibility to infection. At least in the case of duck hepatitis B virus (DHBV), host specificity seems controlled partly at the receptor level. The middle portion in the pre-S region of the viral large envelope protein binds specifically to duck carboxypeptidase D (DCPD) but not to its human or chicken homologue. Although domain C of DCPD is implicated in ligand binding, the exact pre-S contact site remains to be determined. We prepared and tested a panel of chimeric constructs consisting of DCPD and human carboxypeptidase D (HCPD). Our results indicate that a short region at the N terminus of domain C (residues 920 to 949) is critical to DHBV binding and is a major determinant for the host specificity of DHBV infection. Replacing this region of the DCPD molecule with its human homologue abolished the DHBV interaction, whereas introducing this DCPD sequence into HCPD conferred efficient DHBV binding. Extensive analysis of site-directed mutants revealed that both conserved and nonconserved residues were important for the pre-S interaction. There were primary sequence variations and secondary structural differences that contributed to the inability of HCPD to bind the DHBV pre-S domain.

Activation of protein kinase c-delta and c-epsilon by oxidative stress in early diabetic rat kidney

Hyperglycemia-induced oxidative stress and protein kinase C (PKC) activation are implicated in the development and progression of diabetic nephropathy. Although PKC activation under hyperglycemia largely is related to an increase in de novo synthesis of diacylglycerol (DAG), activation of PKC can be regulated sensitively by oxidative stress. We investigated the expression and translocation of PKC isoforms in streptozotocin (STZ)-induced diabetic rat glomeruli and tubules and the effect of an antioxidant taurine. Experimental diabetes was induced by intravenous injection of 50 mg/kg of STZ. Two days after STZ, diabetic rats were assigned to one of two groups: untreated or treated with taurine 1% in drinking water. Four weeks after STZ, PKC isoforms were measured by Western blot analysis in the isolated glomeruli and tubules. DAG-dependent PKC isoforms PKC-alpha, PKC-betaI, PKC-betaII, PKC-delta, and PKC-epsilon and DAG-independent PKC-zeta all were detected in control rat glomeruli and tubules. Streptozotocin increased plasma glucose from 167 +/- 11 mg/dL to 575 +/- 35 mg/dL (n = 9, P < 0.01) and lipid peroxidation from 1.9 +/- 0.2 nmol/mL to 4.2 +/- 0.6 nmol/mL (P < 0.05) and induced proteinuria. In diabetic glomeruli, membrane-associated PKC-delta and PKC-epsilon content increased 47% and 57% above control, and membrane PKC-betaI content decreased to 67% of control. The membrane-associated PKC-alpha, PKC-betaII, and PKC-zeta content were not influenced. Total PKC-delta (163%) and PKC-epsilon (157%) increased significantly in diabetic tubules. Taurine prevented proteinuria and effectively inhibited alterations in PKC-delta and PKC-epsilon of diabetic glomeruli and tubules at dose-inhibiting lipid peroxidation but not hyperglycemia. These data suggest that PKC-delta and PKC-epsilon are sensitively activated by hyperglycemia-induced oxidative stress in diabetic rat kidney.

The involvement of matrix metalloproteinase-9 in airway inflammation of patients with acute asthma

BACKGROUND

Bronchial asthma is an inflammatory disease of the airway characterized by airway remodelling, and is due at least in part to an excess of extracellular matrix (ECM) deposition in the airway wall, which leads to subepithelial collagen deposition. Matrix metalloproteinase-9 (MMP-9) is the major proteolytic enzyme that induces bronchial remodelling in asthma. MMP-9 is also important in the migration of inflammatory cells through basement membrane components.

OBJECTIVES

We evaluated whether airway inflammatory cells correlated with levels of MMP-9 in acute asthma and we examined the time course of sputum levels of MMP-9 activity in patients with spontaneous asthma exacerbation.

METHODS

We performed zymographic analysis and checked levels of MMP-9 by means of enzyme immunoassay. MMP-9 levels were also evaluated during a spontaneous attack of asthma.

RESULTS

Pro-MMP-9 activities and concentrations of MMP-9 in asthmatic patients significantly exceeded those of control subjects (P < 0.01). The activities of pro-MMP-9 were significantly higher in acute asthmatic patients than in stable asthmatic patients (P < 0.01). The elevated MMP-9 activities significantly decreased after 7 and 28 days of therapy. In acute asthmatic patients, the levels of sputum MMP-9 significantly correlated with the total macrophage + neutrophil + eosinophil cell numbers.

CONCLUSION

These data suggest that airway inflammation after asthma exacerbation correlates with the overproduction of MMP-9, which then leads to airway remodelling.

Peritoneal dialysis in diabetic patients

Diabetic nephropathy is the leading cause of end-stage renal disease worldwide. Although death rates of diabetic patients on hemodialysis and peritoneal dialysis (PD) have decreased substantially, they remain higher than rates in nondiabetics on both modalities. PD offers equal or better survival than hemodialysis for younger diabetic patients during early years of dialysis. PD technique survival does not appear different between diabetic and nondiabetic patients but is inferior to hemodialysis technique survival. PD may accelerate changes in peritoneal membrane structure and function in diabetics. Peritonitis and conventional PD solutions containing high glucose and glucose degradation products are implicated in PD technique failure. Increased peritoneal expression of vascular endothelial growth factor and transforming growth factor-beta1 and excessive accumulation of advanced glycosylation end products may be involved in the progressive increase in membrane permeability, loss of ultrafiltration, and peritoneal fibrosis. Nonglucose PD solutions or solutions containing low glucose degradation products may prevent or delay alterations in peritoneal membrane structure and function in diabetic as well as nondiabetic patients during long-term PD.

Intrathoracic malignant peripheral nerve sheath tumor in von Recklinghausen's disease

Malignant peripheral nerve sheath tumor (MPNST) is defined as any malignant tumor arising from or differentiating toward the cells of the peripheral nerve sheath. MPNST accounts for about 5-10% of all soft tissue tumors and is often associated with neurofibromatosis type I (NF-1, von Recklinghausen's disease). It is one of the malignant tumors associated with von Recklinghausen's disease. Its common site is the lower and upper extremities, trunk, head and neck. But intrathoracic manifestations are very rare. We report a case of a 40 year-old man with multiple neurofibromatosis who was presented with an intrathoracic malignant peripheral nerve sheath tumor.

Inhibitory activity for chitin synthase II from Saccharomyces cerevisiae by tannins and related compounds

In the course of search for potent inhibitors of chitin synthase II from natural resources, seven tannins and related compounds were isolated from the aerial part of Euphorbia pekinensis and identified as gallic acid (1), methyl gallate (2), 3-O-galloyl-(-)-shikimic acid (3), corilagin (4), geraniin (5), quercetin-3-O-(2"-O-galloyl)-beta-D-glucoside (6), and kaempferol-3-O-(2"-O-galloyl)-beta-D-glucoside (7). These and nine related compounds, (-)-quinic acid (8), (-)-shikimic acid (9), ellagic acid (10), kaempferol (11), quercetin (12), quercitrin (13), rutin (14), quercetin-3-O-(2"-O-galloyl)-beta-D-rutinoside (15) and 1,3,4,6-tetra-O-galloyl-beta-D-glucose (16), were evaluated for the inhibitory activity against chitin synthase II and III. They inhibited chitin synthase II with IC(50) values of 18-206 microM, except for two organic acids, (-)-quinic acid (8) and (-)-shikimic acid (9). Among them, 3-O-galloyl-(-)-shikimic acid (3) was the most potent inhibitor against chitin synthase II of Saccharomyces cerevisiae with an IC(50) value of 18 microM. The inhibition appears to be selective for chitin synthase II, as they did not appreciably inhibit chitin synthase III.

Gene polymorphisms of endothelial nitric oxide synthase and angiotensin-converting enzyme in patients with lung cancer

The objectives of this study were to examine the possible involvement of endothelial nitric oxide synthase (ecNOS) and angiotensin-converting enzyme (ACE) genes in the genetic basis of lung cancer. Two hundred eighteen patients with lung cancer and 121 healthy subjects were included in this study. The ecNOS and ACE genotypes were determined in all subjects by polymerase chain reaction. The distribution of genotypes of ecNOS gene was significantly different in the lung cancer group than in the control population. ACE genotype distribution was not significantly different in the lung cancer group compared with the control group. These results suggest that polymorphisms of the ecNOS gene, but not the ACE gene, may be associated with the development of lung cancer.

Effects of conventional and new peritoneal dialysis solutions on human peritoneal mesothelial cell viability and proliferation

OBJECTIVE

To investigate the biocompatibility of "new" peritoneal dialysis (PD) solutions with bicarbonate/lactate buffer, non glucose osmotic agents (icodextrin or amino acids), neutral pH, and low levels of glucose degradation products (GDPs).

DESIGN

Using M199 culture medium as a control, we compared conventional and new PD solutions with respect to their effects on the viability of human peritoneal mesothelial cells (HPMCs) [using lactate dehydrogenase (LDH) release], on DNA damage in HPMCs [using single-cell gel electrophoresis (Comet assay)], and on HPMC proliferation (using [3H]-thymidine incorporation). The experiments were performed after cell growth was synchronized by incubation with serum-free media for 24 hours. The PD solutions tested included commercial 1.5% glucose and 4.25% glucose solutions with 40 mmol/L lactate (D 1.5 and D 4.25, respectively), 7.5% icodextrin (E), 1.1% amino acid (N), 1.5% glucose solution in a triple-chambered bag (Bio 1.5), 1.5% glucose solution in a dual-chambered bag with neutral pH (Bal 1.5), and 1.5% glucose and 4.25% glucose solution containing 25 mmol/L bicarbonate and 15 mmol/L lactate (P 1.5 and P 4.25, respectively).

RESULTS

When HPMCs were continuously exposed to undiluted PD solutions, D 1.5, D 4.25, P 4.25, and E increased LDH release by more than 60% at 24 hours. All PD solutions tested increased LDH release by more than 75% at 96 hours. With 2-fold diluted PD solutions, only D 4.25 significantly increased LDH release at 96 hours, though not at 24 hours. When cells were exposed to undiluted PD solutions for 60 min and allowed to recover in M199 for up to 96 hours, LDH release was significantly higher at 24-96 hours in E (55%-69%) and D 1.5 (48%-72%) as compared with control [M199 (18%)]. Release of LDH was significantly lower with PD solutions containing lower levels of GDPs than those in D 1.5, suggesting that GDPs may have a role in cell viability. The D solutions (D 1.5 and D 4.25) and E solution also induced significant DNA damage. Both LDH release and DNA damage by D and E were significantly attenuated by adjusting the solution pH to 7.4, suggesting that low pH may be implicated in PD solution-induced DNA damage and cell death. When diluted 2-fold, D 1.5, D 4.25, and P 4.25 decreased [3H]-thymidine incorporation to 43%, 34%, and 41% of control, respectively, at 24 hours and to 45%, 26%, and 35% of control, respectively, at 96 hours. When cells were exposed to undiluted PD solutions for 5 minutes and allowed to recover in M199 for up to 96 hours, D1.5 and P 4.25--but not D 4.25--significantly inhibited cell proliferation at 24 hours. This effect was sustained up to 96 hours.

CONCLUSIONS

The present in vitro data demonstrate that PD solutions with low pH, or high levels of GDPs, or both, promote HPMC death and DNA damage, and that PD solutions with high osmolality inhibit cell proliferation. Solutions with neutral pH, amino acids, and "low GDPs" appear to be more biocompatible than conventional PD solutions. These results require confirmation in in vivo animal and clinical studies.

First Report of Strawberry Fruit Rot Caused by Alternaria tenuissima in Korea

A strawberry (Fragaria × ananassa Duch.) fruit rot disease has been observed in several vinyl-house fields at Nonsan and Taejon, Chungnam district, Korea, especially following moist and cool conditions in the spring and again in September. Over the past 7 years, incidence of the disease has ranged from 0.2 to 2.0%. Early symptoms on fruits were characterized by small, irregular lesions, which were slightly sunken and appeared light green to black in color as sporulation began. Conidia were 25 to 55 μm long by 10 to 17 μm wide; beaks, when present, were 2 to 3 μm wide and up to 40 μm long; and conidiophores were 20 to 110 μm long by 3 to 5 μm wide. Older lesions were circular, largely sunken, firm, and dark-green to almost black because of abundant sporulation. The fungus isolated from infected fruit tissues was identified as Alternaria tenuissima (Fries) Wiltshire, based on the morphological characteristics of the conidia and conidiophores. Pathogenicity tests were conducted by inoculating slightly wounded, ripe (red) and immature (green) fruits with a conidial suspension (1 × 10⁶ conidia/ml). Twenty-four ripe and immature fruits were inoculated with each of six isolates in duplicate and placed in a moist chamber for 48 h at 25°C and then transferred to vinyl-house field. After 7 to 10 days fruit rot symptoms were visible on the inoculated fruits and appeared nearly identical to lesions observed in the field, although there were differences in aggressiveness among isolates. Control fruits sprayed with distilled water did not develop any symptoms. Green fruits were generally more resistant to infection than ripe ones. The causal fungus was easily reisolated from lesions on inoculated strawberries. Alternaria fruit rot of strawberries has been reported from the USA, UK, and West Germany (2). Howard and Albregts (1) first reported a strawberry fruit rot caused by A. tenuissima in Florida, but the disease is generally not considered important. However, occasionally losses from this disease have been extensive in Korea. To the authors' knowledge, this is the first report of strawberry fruit rot caused by Alternaria tenuissima in Korea. References: (1) C. M. Howard and E. E. Albregts. Phytopathology 63:638-639, 1973. (2) A. L. Snowdon. Pages 250-252 in: A Color Atlas of Post-Harvest Diseases and Disorders of Fruits and Vegetables. Vol. 1. 1990. Wolfe Scientific, London.

A case of bronchiolitis obliterans organizing pneumonia with renal dysfunction after renal transplantation

A 35-year-old male renal transplant patient was admitted with 3-week history of cough and myalgia after a 3-month post-transplantation. The patient's posttransplant course was uncomplicated and had no rejection. But on admission, the serum creatinine was 3.0 mg/dl and high-resolution computed tomography (HRCT) showed bilateral patchy densities and peripheral consolidations. Renal biopsy revealed mononuclear cell infiltration and non-specific tubular injury without evidence of rejection. An open lung biopsy was performed which showed multiple fibroblast plugs filling airspaces that were typical pathologic features of bronchiolitis obliterans with organizing pneumonia (BOOP). After prednisone therapy, the patient's pulmonary symptoms and radiographic findings rapidly recovered and serum creatinine also decreased from 3.0 to 2.1 mg/dl. Although the cause of renal dysfunction was not elucidated, we herein report a rare case of BOOP with renal dysfunction after renal transplantation.

Prevalences of symptoms of asthma and other allergic diseases in korean children: a nationwide questionnaire survey

The purpose of this study was to estimate the national prevalence of childhood asthma and other allergic diseases in Korea, and to determine potential risk factors for the diseases. Stratified random samples of 42,886 were selected from 34 elementary (6-12 yr olds) and 34 middle schools (12-15 yr olds) nationwide, and 38,955 were in the final analysis. The Korean-translated modified version of the International Study of Asthma and Allergies in Childhood questionnaire was used in this cross-sectional survey. Twelve-month prevalences of the symptoms of asthma, rhinoconjunctivitis, and flexural eczema were 8.7%, 10.5%, 7.3% in 6-12 yr olds, and 8.2%, 10.0%, 3.9% in 12-15 yr olds, respectively. For allergic conjunctivitis, food allergy, and drug allergy, the prevalences in 6-12 yr olds were 11.2%, 6.5%, and 1.5%, respectively. Asthma and flexural eczema decreased significantly with age. Other significant risk factors were also noted. For 6-12 yr-old asthma, adjusted odds ratio (aOR) of body mass index was 1.21 with 95% confidence interval (CI) 1.0-1.48, aOR of passive smoking was 1.37 with 95%CI 1.24-1.51, aOR of carpet use was 1.28 with 95%CI 1.10-1.49. For 6-12 yr-old eczema, aOR of affluence was 1.22 with 95%CI 1.07-1.39. The control of obesity and passive smoking would be the most important preventive measures of allergic diseases.

Effect of high glucose on peritoneal mesothelial cell biology

OBJECTIVE

This study reviews evidence that implicates high glucose (HG) in the pathogenesis of peritoneal fibrosis and proposes mechanisms potentially involved in the HG-induced peritoneal fibrosis that is observed in long-term peritoneal dialysis (PD) patients.

DESIGN

Selected Western literature is reviewed, examining the effect of HG on rat or human peritoneal mesothelial cell (HPMC) biology with particular reference to extracellular matrix (ECM) gene expression and protein synthesis.

RESULTS

HG up-regulated the expression of monocyte chemotactic peptide-1 (MCP-1), transforming growth factor beta 1 (TGF beta 1), and fibronectin messenger RNAs (mRNAs) and proteins. These HG-induced up-regulations were effectively blocked by the inhibition of protein kinase C (PKC). In addition, cytosolic reactive oxygen species (ROS) rapidly increased in HPMC cultured under HG, and treatment with antioxidant effectively inhibited HG-induced fibronectin protein synthesis by HPMC.

CONCLUSION

Continuous exposure of the peritoneal membrane to HG may induce changes in HPMC biology, leading to excessive deposition of ECM and peritoneal injury. HG-induced activation of diacylglycerol PKC (DAG-PKC) plays a major role in up-regulation of MCP-1, TGF beta 1, and fibronectin synthesis by HPMC cultured under HG. In addition, ROS, recently recognized as signalling molecules, are rapidly generated in HPMC as a result of increased glucose metabolism and may prove to be an important mediator of HG-induced peritoneal injury.

High glucose-induced PKC activation mediates TGF-beta 1 and fibronectin synthesis by peritoneal mesothelial cells

BACKGROUND

Progressive peritoneal fibrosis, membrane hyperpermeability, and ultrafiltration failure have been observed in long-term peritoneal dialysis (PD) using glucose as an osmotic agent. High glucose activates protein kinase C (PKC), which is one important signal pathway in the activation of transforming growth factor-beta 1 (TGF-beta 1) and fibronectin (FN). To gain a better understanding of mechanisms involved in peritoneal fibrosis, we examined the effects of high glucose on human peritoneal mesothelial cell (HPMC) TGF-beta 1 and FN mRNA expression and protein synthesis and determined the involvement of PKC in the high glucose-induced HPMC activation.

METHODS

Synchronized confluent HPMC were incubated with different concentrations of glucose with and without inhibition of PKC. PKC activity and diacylglycerol (DAG) levels were measured. The expression of TGF-beta 1 and FN mRNAs by HPMC was measured by Northern blot analysis. TGF-beta 1 protein was measured by enzyme-linked immunosorbent assay (ELISA) and mink lung epithelial cell growth inhibition assay. FN protein was measured by Western blot analysis and ELISA.

RESULTS

PKC activity and DAG levels in HPMC cultured under 50 mmol/L (high) glucose increased 2.3- and 2.0-fold, respectively, that of 5.6 mmol/L (control) glucose at 24 hours and this was sustained up to 72 hours. The expression of TGF-beta 1 and FN mRNA by HPMC cultured under high glucose increased 1.6- and 1.7-fold, respectively, that of control values at 24 hours. TGF-beta bioactivity as well as protein content in heat-activated conditioned media from high glucose was significantly higher than that of control values at 24 and 48 hours. FN protein also increased in response to high glucose, as measured by Western blot analysis and ELISA. PKC activator phorbol 12-myristate 13-acetate (PMA) induced 2.2- and 1.4-fold increase in TGF-beta 1 and FN mRNA expression, respectively. Depletion of PKC and calphostin C, a PKC inhibitor, effectively prevented both PMA and high glucose-induced, but not constitutive, expression of TGF-beta 1 and FN.

CONCLUSION

The present data demonstrate that high glucose up-regulates TGF-beta 1 and FN synthesis by HPMC, and that this high glucose-induced up-regulation is largely mediated by PKC. These results suggest that activation of PKC by high glucose in conventional PD solutions may constitute an important signal for activation of HPMC, leading to progressive accumulation of extracellular matrix and eventual peritoneal fibrosis.

Melanocyte repopulation in full-thickness wounds using a cell spray apparatus

Melanocyte restoration is critical in reconstituting skin color. We developed a spotted (piebald) pig wound model to study methods of restoring melanocytes to the epidermis. Paired, full-thickness, porcine wounds were covered with nonpigmented, fully expanded, 3:1 meshed, split-thickness skin grafts and were sprayed with an epidermal cell suspension. The suspensions were highly pigmented skin (HPS) cell isolates for half of the wounds (n = 16) and nonpigmented skin (NPS) cell isolates for the remaining wounds (n = 16). Histologic sections showed 6.0 +/- 3.0 and 15 +/- 4.0 pigmented melanocytes per high-power field on days 8 and 20 in HPS-treated wounds and no pigmented melanocytes in NPS-treated wounds. Melanin pigment was dispersed in all layers of the epithelium for the HPS group on day 20 compared with a lack of melanin pigment observed in the NPS group. Cell spraying may provide a clinical method to restore color to skin; further work is needed to control the expression of melanin.

Preparation and characterization of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) microspheres for the sustained release of 5-fluorouracil

Biodegradable microspheres were prepared with poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV, 85:15 by mole ratio of hydroxybutyrate to hydroxyvalerate) by an water-in-oil-in-water (W/O/W), oil-in-water (O/W) and oil-in-oil (O/O) solvent evaporation method for the sustained release of anti-cancer drug, 5-fluorouracil (5-FU) with controlling the fabrication conditions. The shape of microspheres prepared was relatively rough due to highly crystalline property of PHBV and spherical. The efficiency of 5-FU loading into the PHBV microsphere with O/O method was over 80% compared to that 7% for microspheres by O/W method and below 1% for microspheres by a conventional W/O/W method. However, the most desirable release pattern can be achieved from the O/W method due to the cosolvent effect. The effects of preparation conditions such as the type and amount of surfactant, initial amount of loaded drug, the temperature of solvent evaporation, and etc. on the morphology for W/O/W method were investigated. Possible mechanisms of the desirable sustained release pattern for O/W system have been proposed.

In vivo detection of deposition of radiolabeled lupus antikidney antibody and its inhibition by soluble antigen

This investigation in an animal model was designed to test the feasibility of using radiolabeled lupus antikidney antibody to show renal deposition in vivo and the ability to block this deposition with a binding peptide.

METHODS

BALB/c mice received injections of radiolabeled murine anti-DNA antibody, antibody with no DNA binding capability, and DNA antibody simultaneously with blocking peptide.

RESULTS

Significantly higher renal deposition of anti-DNA antibody than of antibody without DNA binding capability occurred in the animals at 48 h after injection (5.21% of the injected dose per gram of tissue versus 2.5%, P < 0.0004) and at 7-8 d after injection (1.44% versus 0.20%, P < 0.00004). The simultaneous injection of blocking peptide with anti-DNA binding antibody significantly reduced the renal deposition of the anti-DNA antibody at 48 h (1.53%, P < 0.00001) and at 7-8 d (0.64%, P < 0.0017).

CONCLUSION

This study showed the feasibility of using a radiolabeled antibody to evaluate deposition of anti-DNA antibody in the kidney and the successful use of a peptide to block antibody deposition-a strategy that may be useful for renal preservation in lupus. These data support the possibility of using antikidney-labeled antibodies to evaluate immunologic renal disease in vivo in humans.

Sprayed keratinocyte suspensions accelerate epidermal coverage in a porcine microwound model

Keratinocyte suspensions can potentially treat a variety of epidermal defects, but the mechanism of action has not been fully determined. We developed a porcine model to study the effect of sprayed cell suspensions delivered on small wounds within a meshed autograft. Paired full-thickness surgically excised wounds were covered with a fully expanded 3:1 meshed split-thickness autograft. A keratinocyte cell suspension was sprayed onto half of the wounds at a seeding density of 2.8 x 10(3) cells/cm2; the remaining wounds were sprayed with cell culture medium alone. Histologic analysis at days 5 and 8 showed an increase in average epidermal thickness, confluence, keratin cysts, and blood vessels in the keratinocyte cell suspension group compared with the cell culture medium control group. Wounds sprayed with the cell suspension showed faster and better quality of epithelialization than wounds sprayed with cell culture medium alone.

Kinetic resolution of racemic alpha-methyl-beta-propiothiolactone by lipase-catalyzed hydrolysis

Kinetic resolution of racemic alpha-methyl-beta-propiothiolactone (rac-MPTL) using lipases in organic solvent was studied. The lipase from Pseudomonas cepacia (PCL) showed the highest (S)-enantioselectivity (E > 100), and cyclohexane containing 1% (v/v) buffer was identified as the best reaction medium for maintaining high enantioselectivity as well as high reaction rate. While the substrate inhibition was not observed up to 300 mM rac-MPTL, severe product inhibition was observed even at 50 mM racemic 3-mercapto-alpha-methyl propionic acid (rac-MMPA), which made the use of high substrate concentration difficult. To overcome the product inhibition, the products, (R)-MMPA, were neutralized by addition of a dilute basic solution. Although the resolution reaction proceeded further by the base titration, the enantioselectivity of the reaction decreased as a result of nonenantioselective hydrolysis of rac-MPTL in the basic solution. Under these conditions, 200 mM rac-MPTL was successfully resolved to above 95% ee(S) with 53% conversion.