Controlled delivery of a hydrophilic drug from a biodegradable microsphere system by supercritical anti-solvent precipitation technique

The purpose of this study was to prepare microspheres loaded with hydrophilic drug, bupivacaine HCl using poly(D,L-lactic-co-glycolic acid) (PLGA) and poly(L-lactic acid) (PLLA). Microspheres were prepared with varying the PLGA/PLLA ratio with two different levels of bupivacaine HCl (5 and 10%) using a supercritical anti-solvent (SAS) technique. Microspheres ranging from 4-10 microm in geometric mean diameter could be prepared, with high loading efficiency. Powder X-ray diffraction (PXRD) revealed that bupivacaine HCl retained its crystalline state within the polymer and was present as a dispersion within the polymer phase after SAS processing. The release of bupivacaine HCl from biodegradable polymer microspheres was rapid up to 4 h, thereafter bupivacaine HCl was continuously and slowly released for at least 7 days according to the PLGA/PLLA ratio and the molecular weight of PLLA.

Association of the -2510A/G chemokine (C-C motif) ligand 2 polymorphism with knee osteoarthritis in a Korean population

OBJECTIVE

To investigate the possible association between polymorphisms [the -2510A/G promoter polymorphism (rs1024611) and the Cys35Cys coding polymorphism (rs4586) in exon 2] of the chemokine (C-C motif) ligand 2 (CCL2) gene and knee osteoarthritis (OA) in a Korean population.

METHODS

DNA was obtained from 153 Korean primary knee OA patients and 270 healthy controls. CCL2 genomic variants (-2510A/G and Cys35Cys polymorphisms) were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). In additional, the effect of -2510A/G on CCL2 transcription was examined, using a luciferase reporter gene construct transfected into HMC-1 cells.

RESULTS

The -2510A/G promoter polymorphism was associated with OA [genotype frequency, p = 0.041; allele frequency, p = 0.017, odds ratio (OR) = 1.45, 95% confidence interval (CI) = 1.07-1.96]. Significant association was observed between the G carrier of the -2510A/G promoter polymorphism and primary knee OA patients (p = 0.021, OR = 2.25, 95% CI = 1.12-4.52). The G carrier of the -2510A/G promoter polymorphism was also associated with both clinically subtyped OA patients (OA patients with functionally poor index and radiographically severe OA patients). However, no significant difference was found in the Cys35Cys polymorphism. Haplotype frequency analysis revealed a significant difference (chi(2) = 8.98, p = 0.030). The CCL2 serum level of subjects with the G carrier (290.0+/-87.5 pg/mL) of the -2510A/G promoter polymorphism was statistically higher than that of subjects with the non-G carrier (161.5+/-48.3 pg/mL). The luciferase activity was significantly greater from interleukin (IL)-1beta-induced cells transfected with constructs containing G at position -2510.

CONCLUSIONS

The G carrier of the -2510A/G promoter polymorphism was found to be associated with primary knee OA, and could be a susceptibility factor in the development of primary knee OA in the Korean population.

Effect of manufacturing parameters on the characteristics of vitamin C encapsulated tripolyphosphate-chitosan microspheres prepared by spray-drying

To prepare the sustained release vitamin C carriers, vitamin C was successfully encapsulated in tripolyphosphate (TPP) cross-linked chitosan (TPP-chitosan) microspheres by the spray-drying method at different manufacturing conditions. Manufacturing parameters (inlet temperature, liquid flow rate, chitosan concentration and volume of 1% w/v TPP solution) had a significant influence on the characteristics of thus prepared microspheres. The optimum spray-drying conditions such as inlet temperature, liquid flow rate and compressed air flow rate for the encapsulation of vitamin C in TPP-chitosan microspheres was found to be 170 degrees C, 2 ml min(-1) and 101 min(-1), respectively. The size and yield of the TPP-chitosan microspheres ranged from 3.9-7.3 microm and 54.5-67.5%, respectively. The encapsulation efficiency of TPP-chitosan microspheres ranged from 45.72-68.7% and it decreased with the increasing volume of 1% w/v TPP solution. At the same cross-linking extent, the encapsulation efficiency of TPP-chitosan microspheres increased when the concentration of chitosan was increased from 0.5-1% w/v. Effect of volume of 1% w/v TPP solution on the surface morphology of chitosan microspheres was examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). These studies revealed that chitosan solution (250 ml) cross-linked with 15 ml 1% w/v TPP solution produced more porous microspheres than that cross-linked with 5 and 10 ml TPP solution. The release rate of vitamin C from TPP-chitosan microspheres decreased when the concentration of chitosan was increased from 0.5-1.0% w/v. Vitamin C release rate was also modulated by varying the volume of 1% w/v TPP solution. The release rate of vitamin C from TPP-chitosan microspheres decreased with increasing volume (5-15 ml) of 1% w/v TPP solution.

Characteristics of vitamin C encapsulated tripolyphosphate-chitosan microspheres as affected by chitosan molecular weight

In this paper, the effect of chitosan molecular weight on the characteristics (size, encapsulation efficiency, zeta potential, surface morphology and release rate) of vitamin C encapsulated tripolyphosphate cross-linked chitosan (TPP-chitosan) microspheres. The molecular weight of chitosan had a noticeable influence on the size, encapsulation efficiency, zeta potential, surface morphology and controlled release behaviour of the vitamin C encapsulated TPP-chitosan microspheres. The mean particle size and encapsulation efficiencies of TPP-chitosan microspheres were 3.1, 4.9 and 6.7 microm and 67.25, 60.43 and 52.74% for the microspheres prepared using low, medium and high molecular weight chitosan, respectively. All the TPP-chitosan microspheres (low, medium and high molecular weight) had positive charge on their surface. The zeta potential of the TPP-chitosan microspheres prepared using low, medium and high molecular weight chitosan was 41.25, 40.84 and 39.13 mV, respectively. The particle sizes of TPP-chitosan microspheres increased with increases in chitosan molecular weight. Molecular weight of chitosan did not affect significantly the % yield of TPP-chitosan microspheres prepared by spray-drying. The influence of chitosan molecular weight on the surface morphology of vitamin C encapsulated TPP-chitosan microspheres was examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was observed that, as the molecular weight of chitosan increases, TPP-chitosan microspheres with uniform spherical shape could be obtained. The physical state of vitamin C (amorphous or crystalline) in TPP-chitosan matrix was studied by X-ray diffraction (XRD) and it was found that vitamin C is dispersed at the molecular level (amorphous) in the TPP-chitosan matrix. Release rate of the vitamin C from TPP-chitosan microspheres was significantly affected by the chitosan molecular weight. The release rate decreased with increase in the chitosan molecular weight. The release of vitamin C from TPP-chitosan microspheres followed Fick's law of diffusion.

An N-terminal inhibitory domain modulates activity of FoxM1 during cell cycle

The FoxM1 transcription factor plays critical roles in the expression of genes that are essential for cell proliferation. FoxM1 null or depleted cells fail to progress through mitosis, as expression of several mitotic genes depends upon FoxM1. The transcriptional activity of FoxM1 is stimulated by cyclin-cdk-mediated phosphorylation at a site within the transcriptional activation domain. Here, we characterize the role of an N-terminal inhibitory domain in the transcriptional activity of FoxM1. Deletion of the N-terminal 232 amino-acid residues increases the transcriptional and transforming activities of FoxM1. Moreover, while the activity of the full-length FoxM1 is stimulated by growth factors, the activity of the N-terminal deletion mutant is constitutively high in all phases of the cell cycle. The N-terminal deletion also eliminates the requirement for cyclin-cdk to activate FoxM1. We provide evidence that the N-terminal domain interacts with the C-terminal half of the transcription factor to attenuate its transcriptional activity. Moreover, the N-terminal fragment inhibits the transcriptional activity of FoxM1 in G1/S cells, but not in G2/M cells. Our results suggest that cyclin-cdk phosphorylates FoxM1 to counteract the inhibition by the N-terminal domain to fully activate FoxM1 in G2/M phase.

Constitutively wilted 1, a member of the rice YUCCA gene family, is required for maintaining water homeostasis and an appropriate root to shoot ratio

Increasing its root to shoot ratio is a plant strategy for restoring water homeostasis in response to the long-term imposition of mild water stress. In addition to its important role in diverse fundamental processes, indole-3-acetic acid (IAA) is involved in root growth and development. Recent extensive characterizations of the YUCCA gene family in Arabidopsis and rice have elucidated that member's function in a tryptophan-dependent IAA biosynthetic pathway. Through forward- and reverse-genetics screening, we have isolated Tos17 and T-DNA insertional rice mutants in a CONSTITUTIVELY WILTED1 (COW1) gene, which encodes a new member of the YUCCA protein family. Homozygous plants with either a Tos17 or T-DNA-inserted allele of OsCOW1 exhibit phenotypes of rolled leaves, reduced leaf widths, and lower root to shoot ratios. These phenotypes are evident in seedlings as early as 7-10 d after germination, and remain until maturity. When oscow1 seedlings are grown under low-intensity light and high relative humidity, the rolled-leaf phenotype is greatly alleviated. For comparison, in such conditions, the transpiration rate for WT leaves decreases approx. 5- to 10-fold, implying that this mutant trait results from wilting rather than being a morphogenic defect. Furthermore, a lower turgor potential and transpiration rate in their mature leaves indicates that oscow1 plants are water-deficient, due to insufficient water uptake that possibly stems from that diminished root to shoot ratio. Thus, our observations suggest that OsCOW1-mediated IAA biosynthesis plays an important role in maintaining root to shoot ratios and, in turn, affects water homeostasis in rice.

Immediate interlocking nailing versus external fixation followed by delayed interlocking nailing for Gustilo type IIIB open tibial fractures

PURPOSE

To compare immediate interlocking nailing with external fixation followed by delayed interlocking nailing, for Gustilo type IIIB open tibial fractures.

METHODS

23 patients with Gustilo IIIB open tibial fractures were treated with either immediate unreamed interlocking nailing (n=9) or external fixation followed by delayed unreamed interlocking nailing (n=14). Patient age, sex ratio, fracture site, fracture type, and severity were similar in both groups. The time to union, deep infection rate, and nonunion rate in the 2 groups were compared.

RESULTS

In the immediate and delayed nailing groups, respective mean times to union were 21 (standard deviation [SD], 14) months and 14 (SD, 8) months; nonunion rates were 44% (4/9) and 36% (5/14), and deep infection rates were 22% (2/9) and 7% (1/14). All corresponding differences were not statistically significant.

CONCLUSION

Prospective, randomised, multicentre studies are needed to assess whether there are significant differences between the 2 treatment methods.

Investigation of the corticotropin-releasing hormone-proopiomelanocortin axis in various skin tumours

BACKGROUND

Various types of external stress cause the skin and central neuroendocrine system to express corticotropin-releasing hormone (CRH)-proopiomelanocortin (POMC) axis-related hormones. However, the precise role of the CRH-POMC axis-related hormones in various skin tumours is unclear.

OBJECTIVES

This study examined expression patterns of the CRH-POMC axis-related hormones in skin tumours.

METHODS

The production of CRH, adrenocorticotropic hormone (ACTH) and alpha-melanocyte-stimulating hormone (alpha-MSH) in various tumour cell lines including HaCaT and primary keratinocytes was examined using an enzyme-linked immunosorbent assay. Immunohistochemical analysis of the skin tumours was also performed.

RESULTS

CRH, ACTH and alpha-MSH were strongly expressed in malignant skin tumour cell lines such as G-361 and DX-3 (both malignant melanoma, MM). However, normal and haematological malignancy cell lines did not express the CRH-POMC axis-related hormones. Immunohistochemical analysis of the skin tumours showed that MM (80%), squamous cell carcinoma (SCC, 70%) and basal cell carcinoma (BCC, 10%) had strong immunoreactivity (++/+++) for CRH. Strong ACTH and alpha-MSH expression was observed in MM (70% and 50%, respectively), SCC (80% and 60%, respectively) and BCC (70% and 50%, respectively).

CONCLUSIONS

We report that an increase in the level of the CRH-POMC axis-related hormones is associated with malignant skin tumours such as MM. These results highlight the importance of the CRH-POMC axis-related hormones in the malignant tendency of skin tumours.

Structure determination of new analogues of vardenafil and sildenafil in dietary supplements

New analogues of vardenafil and sildenafil illegally added to dietary supplements were detected by high-performance liquid chromatography (HPLC) analysis with a photodiode array detector (PDA). These compounds were isolated and their structures elucidated by mass spectrometry (MS), infrared (IR) spectroscopy, one- and two-dimensional nuclear magnetic resonance (NMR). One of the new analogues given the trivial name pseudovardenafil (compound 1) was structurally elucidated and shown to be 1-[[3-(1,4-dihydro-5-methyl-4-oxo-7-propylimidazo[5,1-f][1,2,4]triazin-2-yl)-4-ethoxyphenyl]sulfonyl]-piperidine. It was a vardenafil analogue isolated from a dietary supplement capsule. Compared with vardenafil, the piperidine ring was substituted for the ethylpiperazine group. The second new analogue, trivially named hydroxyhongdenafil (compound 2), was separated from bulk powder used as a raw material for a dietary supplement. The piperazine and phenyl groups were connected through an acetyl group instead of a sulfonyl group, and hydroxyethylpiperazine was substituted for the methylpiperazine of sildenafil. It was structurally elucidated as 5-[2-ethoxy-5-[[4-(2-hydroxyethyl)-1-piperazinyl]acetyl]phenyl]-1,4-dihydro-1-methyl-3-propyl-7H-pyrazolo[4,3-d]pyrimidin-7-one.

Transdifferentiation of porcine satellite cells to adipoblasts with ciglitizone

Ciglitizone, a class of thiazolidinediones, acts as a potent activator of the adipose differentiation program in established preadipose cell lines. Thiazolidinediones have also been investigated in diabetic patients and have been reported to act as peroxisome proliferator-activated receptor-gamma ligands. Intramuscular adipogenesis or marbling through transdifferentiation of satellite cells in cattle was successfully conducted earlier. In this report, the effects of ciglitizone on the differentiation pathway of porcine myogenic satellite cells was investigated. Semitendinosus muscle was aseptically taken from 10-d-old piglets under general anesthesia, and porcine satellite cells were obtained and grown to near confluence. Postconfluent cells (d 0) were further cultured in differentiation medium containing an adipogenic mixture plus ciglitizone (10 microM) for 48 h. From d 2 onward, the cells were cultured only in the presence of ciglitizone until d 10. Controls were cultured in differentiation medium only. Exposure of porcine satellite cells to the adipogenic mixture plus ciglitizone generated lipid droplets on d 2, and subsequently, exposure of cells to ciglitizone alone helped in cytoplasmic lipid filling, providing them with the acquisition of adipocyte morphology. An increase (P < 0.05) in the fusion (structures containing 2 to 3 nuclei) of satellite cells was observed, and myosin heavy chain appeared with greater intensity (immunohistochemistry) in the control group from d 2 onward. Adipocyte-specific transcriptional factors (i.e., CCAAT/enhancer binding protein-alpha and peroxisome proliferator-activated receptor-gamma) were predominant during transdifferentiation and were observed with immunohistochemistry, Western blot (approximately 47.2 and approximately 60.4 kDa, respectively), and real-time PCR. Ciglitizone appeared to convert the differentiation pathway of satellite cells into that of adipoblasts.

Transgenic rice lines expressing maize C1 and R-S regulatory genes produce various flavonoids in the endosperm

Flavonoids, compounds that possess diverse health-promoting benefits, are lacking in the endosperm of rice. Therefore, to develop transgenic lines that produce flavonoids, we transformed a white rice cultivar, Oryza sativa japonica cv. Hwa-Young, with maize C1 and R-S regulatory genes. Expression of these transgenes was restricted to the endosperm using the promoter of a rice prolamin gene. The pericarp of the C1/R-S homozygous lines became dark brown in accordance with their maternal genotype, whereas the endosperm turned chalky, similar to the opaque kernel phenotype. Analysis via high-performance liquid chromatography (HPLC) revealed that numerous kinds of flavonoids were produced in these transgenic kernels. To identify individual flavonoids, the number of HPLC peaks was reduced through moderate acid hydrolysis, followed by ethyl acetate partitioning. Amongst the major flavonoids, dihydroquercetin (taxifolin), dihydroisorhamnetin (3'-O-methyl taxifolin) and 3'-O-methyl quercetin were identified through liquid chromatography/mass spectrometry/mass spectrometry and nuclear magnetic resonance analyses. Fluorescence labelling with diphenylboric acid showed that the flavonoids were highly concentrated in the cells of four to five outer endosperm layers. More importantly, a high fluorescence signal was present in the cytosol of the inner endosperm layers. However, the overall signal in the inner layers was significantly lower because starch granules and protein bodies occupied most of the cytosolic space. Our estimate of the total flavonoid content in the transgenic kernels suggests that C1/R-S rice has the potential to be developed further as a novel variety that can produce various flavonoids in its endosperm.

The plasma alpha-synuclein levels in patients with Parkinson's disease and multiple system atrophy

alpha-Synuclein, a synaptic protein of unknown function, is a major component of Lewy bodies and may play a role in the pathophysiological process of Parkinson's disease (PD). In this study, we measured the plasma alpha-synuclein levels in 105 patients with PD, 38 patients with multiple system atrophy (MSA), and 51 age-matched controls. The alpha-synuclein level was significantly elevated in patients with PD (79.9 +/- 4.0 pg/ml, p < 0.001) and in those with MSA (78.1 +/- 3.5 pg/ml, p = 0.019) compared with the level in controls (76.1 +/- 3.9 pg/ml). The alpha-synuclein level was higher in patients with PD than in those with MSA (79.9 +/- 4.0 vs 78.1 +/- 3.5, p = 0.016). Our study demonstrated that the alpha-synuclein level in plasma is elevated in patients with PD and MSA.

Implications of increased tumor blood flow and oxygenation caused by mild temperature hyperthermia in tumor treatment

In many past clinical studies in which hyperthermia enhanced the efficacy of radiotherapy, the tumor temperatures could be raised only to 40-42 degrees C range in most cases. The heat-induced cell death, cellular radiosensitization, and vascular damage induced by such mild temperature hyperthermia (MTH) are likely to be insignificant despite the increased response of tumors to radiotherapy. Heating rodent tumors at 40-42 degrees C was found to cause an enduring increase in blood flow and oxygenation in the tumors. Recent studies with canine soft tissue sarcoma and human tumor clinical studies also demonstrated that MTH improves tumor oxygenation, and enhances response of the tumors to radiotherapy or chemoradiotherapy. The increased blood flow and vascular permeability caused by MTH may also improve the delivery of various therapeutic agents such as chemotherapy drugs, immunotherapeutic agents and genetic constructs for gene therapy to tumor cells. MTH as a means to potentiate the efficacy of radiotherapy and others warrants further investigation.

Arabidopsis calcium-dependent protein kinase AtCPK32 interacts with ABF4, a transcriptional regulator of abscisic acid-responsive gene expression, and modulates its activity

The phytohormone abscisic acid (ABA) regulates stress-responsive gene expression during vegetative growth. The ABA regulation of many genes is mediated by a subfamily of basic leucine zipper class transcription factors referred to as ABFs (i.e. ABF1-ABF4), whose transcriptional activity is induced by ABA. Here we show that a calcium-dependent protein kinase is involved in the ABA-dependent activation process. We carried out yeast two-hybrid screens to identify regulatory components of ABF4 function and isolated AtCPK32 as an ABF4-interacting protein. AtCPK32 has autophosphorylation activity and can phosphorylate ABF4 in vitro. Mutational analysis indicated that serine-110 of ABF4, which is highly conserved among ABF family members, may be phosphorylated by AtCPK32. The serine-110 residue is essential for ABF4-AtCPK32 interaction, and transient expression assay revealed that it is also required for the normal transcriptional function of ABF4. The expression patterns and subcellular localization of AtCPK32 are similar to those of ABF4. Furthermore, its overexpression affects both ABA sensitivity and the expression of a number of ABF4-regulated genes. Together, our data demonstrate that AtCPK32 is an ABA signaling component that regulates the ABA-responsive gene expression via ABF4.

Production of optically active ketoprofen by direct enzymatic esterification

For the production of optically active ketoprofen, enzymatic resolution of racemic ketoprofen in an organic solvent has been accomplished via enantioselective esterification. Pharmacologically inactive (R)-ketoprofen is converted into the corresponding (R)-ester by this method. Enantioselectivity in lipase-catalyzed resolution of racemic ketoprofen was mainly dependent on the sources of lipase, alcohol moiety, organic solvent, and water content. Ethanol was used as the alkyl donor and the optimum water content required for highly efficient enzymatic resolution was determined to be 0.1-0.15% (v/v), which was maintained using salt hydrates such as Na2SO4 x 10H2O. (S)-Ketoprofen could be obtained with high enantioselectivity (E=15) in n-hexane supplemented with ethylene dichloride (20% (v/v)) using commercially available Candida antarctica lipase (Novozym 435).

Identification and characterization of the peroxiredoxin gene family in chickens

Peroxiredoxin (PRX) is a crucial antioxidant protein that protects against endogenously produced peroxides in prokaryotes to eukaryotes. To date, 6 different isoforms have been identified in mammals. In this study, we describe the first members of the PRX protein family to be characterized in Chicken. Through bioinformatics analysis, we observed that at least 4 different classes of PRX protein have been evolutionarily conserved in chickens. Furthermore, in vitro functional assays of the candidate chicken PRX proteins demonstrated that they had levels of antioxidant activity similar to those of the mammalian enzymes. The expression patterns of the PRX transcript in several chicken tissues were not tissue specific, suggesting that they might play an essential role as a housekeeping gene in all tissues to protect against oxidative damage. In conclusion, the sequences of the putative members of this functional gene family in chickens could be effectively retrieved in silico through bioinformatics analysis, and the functionality of their gene products evaluated by in vitro comparative assay.

Discovery of SNPs in soybean genotypes frequently used as the parents of mapping populations in the United States and Korea

Single nucleotide polymorphisms (SNPs) including insertion/deletions (indels) serve as useful and informative genetic markers. The availability of high-throughput and inexpensive SNP typing systems has increased interest in the development of SNP markers. After fragments of genes were amplified with primers derived from 110 soybean GenBank ESTs, sequencing data of PCR products from 15 soybean genotypes from Korea and the United States were analyzed by SeqScape software to find SNPs. Among 35 gene fragments with at least one SNP among the 15 genotypes, SNPs occurred at a frequency of 1 per 2,038 bp in 16,302 bp of coding sequence and 1 per 191 bp in 16,960 bp of noncoding regions. This corresponds to a nucleotide diversity (theta) of 0.00017 and 0.00186, respectively. Of the 97 SNPs discovered, 78 or 80.4% were present in the six North American soybean mapping parents. The addition of "Hwaeomputkong," which originated from Japan, increased the number to 92, or 94.8% of the total number of SNPs present among the 15 genotypes. Thus, Hwaeomputkong and the six North American mapping parents provide a diverse set of soybean genotypes that can be successfully used for SNP discovery in coding DNA and closely associated introns and untranslated regions.

Coptis japonica root extract induces apoptosis through caspase3 activation in SNU-668 human gastric cancer cells

Apoptosis-modulating approaches offer an attractive opportunity for therapeutic use for many tumors. We investigated the effects of the roots of Coptis japonica var. dissecta (Ranunculaceae) on human gastric cancer cells, SNU-668. The cytotoxicity of Coptis japonica at 100 microg/ml (methanol extract) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was 13.89 +/- 1.91% of control value. Considering the features by 4,6-diamidino-2-phenylindole (DAPI) staining and terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, it was confirmed that the death of SNU-668 cells was due to apoptosis. In the apoptosis-regulating genes, BCL2 expression was diminished out, whereas BAX and CASP3 expressions were increased, compared with control. Furthermore, the activity of caspase3 was significantly increased by Coptis japonica treatment. These results suggest that Coptis japonica could induce apoptotic anticancer effect through caspase3 activation on SNU-668 human gastric cancer cells.

Genetic association study of adiponectin polymorphisms with risk of Type 2 diabetes mellitus in Korean population

AIMS

To investigate any association between Type 2 diabetes mellitus and two single nucleotide polymorphisms (SNPs) in the adiponectin gene, T45G and G276T, in the Korean population.

METHODS

We genotyped 427 non-diabetic controls and 493 Type 2 diabetic patients for SNPs T45G and G276T of adiponectin gene, measured plasma adiponectin concentrations, and examined clinical parameters in Koreans.

RESULTS

There were no statistically significant differences in allele frequencies of SNPs 45 and 276 comparing control with Type 2 diabetic subjects (T frequency 68.3% vs. 71.6%, P=0.13 for SNP45, G frequency 72.2% vs. 68.9%, P=0.12 for SNP276). The genotype distributions of these SNPs had no association with the risk of Type 2 diabetes and metabolic parameters of insulin resistance. Plasma levels of adiponectin were not statistically different according to T45G and G276T either, in both control and Type 2 diabetic subjects.

CONCLUSION

The T45G and G276T of the adiponectin gene may not be an important determinant of Type 2 diabetes or insulin resistance in Korean subjects.

Impact of IL-1 receptor antagonist gene polymorphism on schizophrenia and bipolar disorder

OBJECTIVES

Variable levels of cytokines were observed in patients with schizophrenia and bipolar disorder, and an especially high level of interleukin-1 (IL-1) was detected in schizophrenia patients. It is known that IL-1 receptor antagonist (IL-1RA) binds to IL-1 receptors and inhibits the receptor binding of IL-1alpha and IL-1beta.

METHODS

In this study, the association between the variable number of tandem repeats polymorphism of the IL-1RA gene and schizophrenia (n=269) and bipolar disorder (n=83) was investigated.

RESULTS

The genotype distribution and allele frequency were significantly different between schizophrenic patients and the control group (P<0.05); however, there were no prominent differences between bipolar patients and the control group. The carriage rate for the IL1RN*2 allele was associated with higher risk of schizophrenia (odds ratio=2.24).

CONCLUSIONS

This study indicates that IL-1RA could be a candidate gene for susceptibility to schizophrenia.

4-1BB promotes long-term survival in skin allografts treated with anti-CD45RB and anti-CD40L monoclonal antibodies

4-1BB (CD137) is a T-cell co-stimulatory molecule that promotes T cell activation. Using a skin transplantation model, we observed that simultaneous administration of monoclonal antibodies (mAb) targeting CD45RB and CD40L prolonged skin allograft in co-stimulation blockade (CTLA4-Ig and anti-CD40L mAb)-resistant mice, because of reducing CD8(+) T cells and CD4(+) CD45RB(high) T cells. Anti-CD45RB mAb (45RB) blocks the activation of T helper 1 (Th1) cells and generates regulatory T cells (T(reg)). The experimental design included five groups: group 1, control; group 2, 45RB-MR1; group 3, 45B-MR1 + 4-IBBL; group 4, anti-CD4 mAb plus group 3 treatment; group 5, anti-CD8 mAb plus group 3 treatment. In this study we highlight the involvement of 4-1BB/4-1BBL in the development of T-cell responses. C57BL/6 recipients of BALB/c skin grafts were treated with 45RB, anti-CD40L mAb (MR1), and antagonistic anti-4-1BBL mAb (4-1BBL) on days 0, 2, 4, 6, and 8 posttransplantation. Additional 4-1BBL further prolonged skin graft survival, although the percentage of splenocyte-derived CD8(+) T cells was reduced similarly in both groups. Use of 4-1BBL seems to have additive effects on T(reg) cells, which play a major role in the maintenance of tolerance. Even after immunosuppressive therapy in combination with CD4(+) T-cell depletion, we did not achieve prolonged graft survival, possibly because of the absense of T(reg) cells, which require CD4-independent CD8(+) T cells, based on the observation of increasing proportion of CD8(+) T cells in similar degree as the control group.

Survival of freeze-dried Lactobacillus bulgaricus KFRI 673 in chitosan-coated calcium alginate microparticles

The aim of this study was to investigate the effect of alginate microparticles coated with three kinds of chitosans of different molecular weights on the survival of Lactobacillus bulgaricus KFRI 673 in simulated gastric (SGJ) and intestinal juices (SIJ) and on their stability during storage at 4 and 22 degrees C. L. bulgaricus KFRI 673 loaded in alginate microparticles was prepared by spraying the mixture of sodium alginate and cell culture into the calcium chloride solution using an air-atomizing device. When L. bulgaricus KFRI 673 was exposed to SGJ of pH 2.0 for 60 min, none of the microorganism survived. Contrary to this result, microbiological analysis indicated that microencapsulation in alginate microparticles improved the survival of acid-sensitive L. bulgaricus KFRI 673 in SGJ and that high molecular weight chitosan coating resulted in the highest survival in SGJ. To study storage stability of free and microencapsulated cells, in vitro studies were conducted at 4 and 22 degrees C during a 4 week period. Both free and microencapsulated cells showed similar stabilities during 4 weeks of storage at 4 degrees C. However, the stability of Lactobacillus at 22 degrees C was appreciably improved when loaded in high molecular weight chitosan-coated alginate microparticles. In conclusion, microencapsulation of lactic acid bacteria with alginate and chitosan coating offers an effective way of delivering viable bacterial cells to the colon and maintaining their survival during refrigerated storage.

Baicalin induces NAD(P)H:quinone reductase through the transactivation of AP-1 and NF-κB in Hepa 1c1c7 cells

Baicalin (5,6,7-trihydroxyflavone-7-O-D-glucuronic acid, BA) is a flavone isolated from Scutellariae radix. In our previous report BA was a major active principle of NAD(P)H:quinone reductase (QR) induction mediated by Scutellariae radix extract and the induction was related to the transcriptional activation of the QR gene in Hepa 1c1c7 cells. The primary aim of the present study was to determine the molecular mechanism of QR gene expression by baicalin. The antioxidant or electrophile response element (ARE/EpRE) found at the 5'-flanking region of phase II genes may play an important role in mediating their induction by xenobiotics, including chemopreventive agents. In accordance, to study the molecular mechanisms of QR gene expression by BA, electrophoretic mobility shift assay (EMSA), using nuclear extracts of treated and untreated cells against ARE, activator protein-1 (AP-1) or nuclear factor-kappaB (NF-kappaB) binding sites, showed that BA increased the binding levels of the parameters in a dose-dependent manner. Further, Hepa 1c1c7 cells were transiently transfected with a plasmid containing three copies of the AP-1- or NF-kappaB-binding site linked to a chloramphenicol acetyltransferase (CAT) reporter gene. Using the CAT reporter gene assay, a dose-dependent transactivation of AP-1- or NF-kappaB-mediated CAT expression was observed with the treatment of BA. These results clearly indicate that BA induces the QR gene expression and activity by transactivation of AP-1 and NF-kappaB, and thus BA may be considered as a potential cancer chemopreventive agent with the induction of phase II detoxification enzyme.

Abnormal motor behavior and vestibular dysfunction in the stargazer mouse mutant

In stargazer mutant mice, a mutation in the gene encoding stargazin results in absence epilepsy, cerebellar ataxia, and a characteristic abnormal motor syndrome. The main goal of the current studies was to characterize the nature and source of the abnormal motor behavior. Because the stargazer motor syndrome resembles that of other rodents with vestibular dysfunction, the motor abnormalities were compared with those of normal mice treated with toxins known to damage the vestibular system. Quantitative open field assessments revealed that the stargazer mice display a motor syndrome very similar to that exhibited by mice with toxin-induced vestibulopathy. However, stargazer mice also displayed several additional behaviors, such as ataxic gait and sustained extensor movements of the neck. In addition, stargazer mice performed worse than mice with toxin-induced vestibulopathy in most standard tests of motor function. Motor function was also impaired on each of four behavioral tests sensitive to vestibular function. Because of the close associations between the vestibular and auditory systems, tests of auditory function were also employed. The stargazer mutants exhibited relatively normal auditory brainstem evoked responses but no apparent acoustic startle reflex. Histological examination of vestibular sensory epithelium at the light and electron microscopic levels confirmed the existence of abnormalities in the stargazer mutants. These results imply a previously unrecognized role for stargazin in the normal functions of the vestibular system and indicate that some, but not all, of the abnormal motor syndrome of stargazer mice can be attributed to vestibular dysfunction.

Suppressive effects of nitric oxide production and inducible nitric oxide synthase (iNOS) gene expression by Calystegia soldanella methanol extract on lipopolysaccharide-activated RAW 264.7 cells

Since nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) has been found to be involved in various pathophysiological processes, including inflammation and carcinogenesis, the modulators of NO synthesis or expression have been considered as potential anti-inflammatory and cancer chemopreventive agents. In this study, to procure the iNOS inhibitors from natural products, we evaluated 57 methanol extracts of natural products including Korean indigenous plants for the inhibition of NO formation on lipopolysaccharide (LPS)-activated mouse macrophage-like RAW 264.7 cells. As a result, several extracts including those from Actinodaphne lancifolia, Calystegia soldanella, Caryratia japonica, Citrus dachibana, Dystaenia takeshimana, Erysimum aurantiacum, Hovenia undulata, Stewartia koreana and Viburnum awabuki showed potent inhibitory activities of NO production (>70% inhibition at the test concentration of 40 microg/ml). In particular, the extract of Calystegia soldanella showed a potential inhibition of NO production in a dose-dependent manner (IC50=4.3 microg/ml). Subsequent study also exhibited that the extract of Calystegia soldanella significantly suppressed iNOS protein and gene expression in a dose-dependent manner. These results suggest that Calystegia soldanella might be a new potential candidate for developing an iNOS inhibitor from natural products and also could be warranted for further elucidation of active principles for the development of new anti-inflammatory and/or cancer chemopreventive agents.

Effects of Paeonia lactiflora root extracts on the secretions of monocyte chemotactic protein-1 and -3 in human nasal fibroblasts

In the field of Oriental medicine, the root of Paeonia lactiflora (Paeoniae Radix) has been prescribed usually to treat the common cold, and it was thought to alleviate upper respiratory infection or nasal inflammation. Monocyte chemotactic proteins (MCP)-1 and MCP-3 are known as the most potent chemokines to mediate allergic inflammation. The object of the study was to investigate the effect of Paeoniae Radix on the release of the chemokines such as MCP-1 and MCP-3. To detect the secretion of MCPs, an enzyme-linked immunosorbent assay was performed for human nasal mucosal fibroblasts after stimulation with several cytokines such as tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma) and interleukin-1beta (IL-1beta). The secretion of MCP-1 was increased after stimulation with TNF-alpha or IL-1beta treatment. Co-treatment of TNF-alpha and IFN-gamma, or IL-1beta and IFN-gamma increased the secretion of MCP-1 and MCP-3. Paeoniae Radix was tested with inflammatory cytokines, and the results showed that the Paeoniae Radix significantly decreased the secretion of MCP-1 and MCP-3. In our study, Paeoniae Radix may play an important role in nasal inflammation with a modulation of MCP-1 and MCP-3.

A chronic heart failure model by coronary artery ligation in the goat

The availability of a reliable heart failure model in large animals is important. We report upon our efforts to develop a chronic heart failure model in seven goats using sequential ligation of the left anterior descending (LAD) coronary artery and its diagonal branch. After anesthesia and left thoracotomy, the LAD artery was ligated, and the diagonal vessel at the same level was ligated one hour later. Cardiac measurements were performed with a thermodilution catheter and by ultrasonography. Two months after the operation, the same measurements were made and animals were sacrificed for postmortem examinations of their hearts. Hemodynamic measurements, except cardiac output, showed no significant changes immediately after the coronary artery ligation. Echocardiographic measurements showed significant changes in the ejection fraction and fractional shortening without changes in left ventricular dimensions. Wall motion analyses demonstrated variable degrees of anteroseptal dyskinesia and akinesia in all animals immediately after coronary artery ligation. Five animals have undergone hemodynamic and ultrasonographic studies 2 months after coronary artery ligation. The results obtained from these animals showed significant increases in central venous pressure, right ventricular pressure, pulmonary artery pressure, and pulmonary artery capillary wedge pressure, and a significant decrease in cardiac output. Increases in left ventricular dimensions and decreases in ejection fraction with fractional shortening in ultrasonographic studies were also observed. Pathologically, well-demarcated thin-walled anteroseptal infarcts, with chamber enlargement, were clearly seen with dilatation of the heart chambers in all specimens. Based on this study, we conclude that goats, like sheep, can provide a reliable model of chronic heart failure by coronary artery ligation and in view of the many advantages offered by goats, we believe that this animal model will be useful for cardiac experimentation.

Common genetic polymorphisms in the promoter of resistin gene are major determinants of plasma resistin concentrations in humans

AIMS/HYPOTHESIS

Resistin is thought to be an important link between obesity and insulin resistance. It has been suggested that genetic polymorphism in the promoter of resistin gene is a determinant of resistin mRNA expression and possibly associated with obesity and insulin resistance. In this study, we investigated the association between the genotype of resistin promoter and its plasma concentrations.

METHODS

We examined g.-537A>C and g.-420C>G polymorphisms in the resistin promoter and measured plasma resistin concentrations in Korean subjects with or without Type 2 diabetes. We also did haplotype-based promoter activity assays and the gel electrophoretic mobility shift assay.

RESULTS

The -420G and the -537A alleles, which were in linkage disequilibrium, were associated with higher plasma resistin concentrations. Individuals with haplotype A-G (-537A and -420G) had significantly higher plasma resistin concentrations than the others. Haplotype A-G had modestly increased promoter activity compared to the other haplotypes. Electrophoretic mobility shift assay showed that the -420G allele is specific for binding of nuclear proteins from adipocytes and monocytes. However, none of the two polymorphisms were associated with Type 2 diabetes or obesity in our study subjects.

CONCLUSIONS/INTERPRETATION

Polymorphisms in the promoter of resistin gene are major determinants of plasma resistin concentrations in humans.

Chitosan microparticle preparation for controlled drug release by response surface methodology

The objectives were to investigate the effects of formulation variables on the release of drug and to optimize the formulation of chitosan microparticles loaded with drug for controlled release using response surface methodology. Chitosan microparticles were prepared by dropping a chitosan solution into sodium tripolyphosphate (TPP) through ionic cross-linking. The release behaviour of felodipine as a model drug was affected by preparation variables. A central composite design was used to evaluate and optimize the effect of preparation variables, chitosan concentration (X1), the pH of the TPP solution (X2) and cross-linking time (X3) on the cumulative per cent drug release (Y) in 24 h. Chitosan concentration and cross-linking time affected negatively the release of felodipine, while the pH of the TPP did so positively and was the highest influential factor. The optimum rate of drug release, 100% in 24 h, was achieved at 1.8% chitosan concentration, a pH 8.7 for the TPP solution and 9.7 min cross-linking time.

Effects of Jaoga-Yukmiwon®, a Korean herbal medicine, on chondrocyte proliferation and longitudinal bone growth in adolescent male rats

Externally visible growth of the body is the result of proliferation of chondrocytes and longitudinal bone growth. The effects of the Korean herbal medicine, Jaoga-Yukmiwon((R)), on the growth of adolescent rats were investigated in the present study. The proliferation ratio of chondrocytes was calculated from 5-bromo-2'-deoxyuridine incorporation during DNA synthesis. The 5-bromo-2'-deoxyuridine incorporation ratio of the control group was 21.1 +/- 3.5%, and Jaoga-Yukmiwon((R)) administration markedly increased the ratio to 34.5 +/- 4.6% (p < 0.05). The bone formation rate of longitudinal bone was estimated by labelling with tetracycline, which binds to newly formed bone. The bone formation rate in the tibia of Jaoga-Yukmiwon((R))-administered rats was increased to 405.1 +/- 4.3 micro m (p < 0.05) from 292.2 +/- 11.8 micrometer (control value). The height of the growth plate in the administrated rats was increased to 614.6 +/- 10.0 micro m (p < 0.05) from 552.3 +/- 17.1 micro m. The bone morphogenetic protein-2 immunostaining in the growth plate was also increased. These results suggest that Jaoga-Yukmiwon((R)) may promote longitudinal bone growth during the developmental period.

Induction of apoptosis by carboplatin and hyperthermia alone or combined in WERI human retinoblastoma cells

This paper investigated the induction of apoptosis and perturbation of cell cycle progression caused by carboplatin (CPt) and hyperthermia alone or combined in WERI human retinoblastoma cells in vitro. An incubation of the cells with 25 or 50 microm of CPt at 37 degrees C caused apoptosis, which progressively increased during the 24-72 h treatment. Hyperthermia at 42.5 degrees C for 1 h induced apoptosis, which became significant from 24 h after the heating. Heating the cells in the presence of CPt and subsequent incubation with CPt was far more effective than treating the cells with hyperthermia or CPt treatment alone in inducing apoptosis in the WERI cells, indicating that the combination of these two modalities is potentially useful for the treatment of retinoblastoma. It appeared that the apoptosis in WERI cells caused by hyperthermia and CPt occurs during G1 phase. An interesting observation was that caspase 9 activation preceded the release of cytochrome C from mitochondria during apoptosis in WERI cells, contrary to the general notion that caspase 9 is activated by cytochrome C.

The origin of cells that repopulate patellar tendons used for reconstructing anterior cruciate ligaments in man

Cryopreserved patellar tendon allografts are often recommended for reconstruction of anterior cruciate ligaments (ACLs) because living donor fibroblasts are thought to promote repair. Animal studies, however, indicate that ligaments regenerate from recipient rather than donor cells. If applicable to man, these observations suggest that allograft cell viability is unimportant. We therefore used short tandem repeat analysis with polymerase chain reaction (PCR) amplification to determine the source of cells in nine human ACLs reconstructed with cryopreserved patellar tendon allografts. PCR amplification of donor and recipient DNA obtained before operation and DNA from the graft obtained two to ten months after transplantation revealed the genotype of cells and showed only recipient cells in the graft area. Rather than preserve the viability of donor cells, a technique is required which will facilitate the introduction of recipient cells into patellar tendon allografts.

Preparation and release characteristics of polymer-coated and blended alginate microspheres

To prevent a rapid drug release from alginate microspheres in simulated intestinal media, alginate microspheres were coated or blended with polymers. Three polymers were selected and evaluated such as HPMC, Eudragit RS 30D and chitosan, as both coating materials and additive polymers for controlling the drug release. This study focused on the release characteristics of polymer-coated and blended alginate microspheres, varying the type of polymer and its concentration. The alginate microspheres were prepared by dropping the mixture of drug and sodium alginate into CaCl(2) solution using a spray-gun. Polymer-coated microspheres were prepared by adding alginate microspheres into polymer solution with mild stirring. Polymer-blended microspheres were prepared by dropping the mixture of drug, sodium alginate and additive polymer with plasticizer into CaCl(2) solution. In vitro release test was carried out to investigate the release profiles in 500 ml of phosphate buffered saline (PBS, pH 7.4). As the amount of polymer in sodium alginate or coating solution increase, the drug release generally decreased. HPMC-blended microspheres swelled but withstood the disintegration, showing an ideal linear release profiles. Chitosan-coated microspheres showed smooth and round surface and extended the release of drug. In comparison with chitosan-coated microspheres, HPMC-blended alginate microspheres can be easily made and used for controlled drug delivery systems due to convenient process and controlled drug release.

Linoleic acid-induced VCAM-1 expression in human microvascular endothelial cells is mediated by the NF-kappa B-dependent pathway

Vascular cell adhesion molecule-1 (VCAM-1) has been reported to play an important role in cancer metastasis via the adhesive interaction between tumor cells and endothelial cells. In this study, we examined the effects of linoleic acid on VCAM-1 expression and its transcriptional regulatory mechanism in human microvascular endothelial cells (HMEC-1). Time- and dose-dependent increases of VCAM-1 mRNA levels were observed in linoleic acid-treated HMEC-1 as detected by reverse transcriptase-polymerase chain reaction. Flow cytometry analysis showed a significant and dose-dependent upregulation of VCAM-1 expression in HMEC-1 stimulated with linoleic acid compared with controls. To clarify the transcriptional regulatory pathway, we investigated the role of nuclear factor-kappa B (NF-kappa B) in the expression of VCAM-1 by linoleic acid in HMEC-1. Nuclear extracts from HMEC-1 stimulated with linoleic acid showed a dose-dependent increase in binding activity to the NF-kappa B consensus sequences. These effects were preventable by cotreatment with inhibitors of NF-kappa B activity, such as sodium salicylate, aspirin, or pyrrolidine dithiocarbamate. In addition, pretreatment with NF-kappa B inhibitors markedly suppressed the ability of linoleic acid to induce VCAM-1 gene expression. The role of NF-kappa B in linoleic acid-induced VCAM-1 expression was confirmed by functional promoter studies in HMEC-1 transfected with reporter constructs of the VCAM-1 promoter with or without mutated NF-kappa B binding site. These results indicate that linoleic acid upregulates VCAM-1 expression in HMEC-1 through the NF-kappa B-dependent pathway.

Preparation and characterization of chitosan microparticles intended for controlled drug delivery

Chitosan microparticles were prepared with tripolyphosphate (TPP) by ionic crosslinking. The particle sizes of TPP-chitosan microparticles were in range from 500 to 710 microm and encapsulation efficiencies of drug were more than 90%. The morphologies of TPP-chitosan microparticles were examined with scanning electron microscopy. As pH of TPP solution decreased and molecular weight (MW) of chitosan increased, microparticles had more spherical shape and smooth surface. Release behaviors of felodipine as a model drug were affected by various preparation processes. Chitosan microparticles prepared with lower pH or higher concentration of TPP solution resulted in slower felodipine release from microparticles. With decreasing MW and concentration of chitosan solution, release behavior was increased. The release of drug from TPP-chitosan microparticles decreased when cross-linking time increased. These results indicate that TPP-chitosan microparticles may become a potential delivery system to control the release of drug.

Preparation and characterization of drug-loaded polymethacrylate microspheres by an emulsion solvent evaporation method

Microspheres containing the anti-hypertension drug, felodipine, were prepared by the emulsion solvent evaporation method (o/o) using acrylate methacrylate copolymers, Eudragit RL PO and Eudragit RS PO, as wall materials. In order to increase the encapsulation efficiency, a mixed solvent system comprising 1:1 proportions of acetonitrile and dichloromethane was used as a dispersed phase. The morphology of the microspheres was evaluated using a scanning electron microscope, which showed a spherical shape with smooth surface. The mean sphere diameter was between 9.5-13.2 microm and the microencapsulation efficiencies ranged from 51.4-80.4%. The release profiles and encapsulation efficiencies depended strongly on the structure of the polymers used as wall materials. The release rate of the Eudragit RS PO microspheres was much lower than that of Eudragit RL PO microspheres. Whereas Eudragit RL PO microspheres followed the Higuchi rule, Eudragit RS PO microspheres exhibited a triphasic release profile. It is concluded that drug release rate can be controlled by choice of polymer type.

Preparation of alginate beads for floating drug delivery system: effects of CO(2) gas-forming agents

Floating beads were prepared from a sodium alginate solution containing CaCO(3) or NaHCO(3) as gas-forming agents. The solution was dropped to 1% CaCl(2) solution containing 10% acetic acid for CO(2) gas and gel formation. The effects of gas-forming agents on bead size and floating properties were investigated. As gas-forming agents increased, the size and floating properties increased. Bead porosity and volume average pore size, as well as the surface and cross-sectional morphology of the beads were examined with Mercury porosimetry and Scanning Electron Microscopy. NaHCO(3) significantly increased porosity and pore diameter than CaCO(3). Incorporation of CaCO(3) into alginate solution resulted in smoother beads than those produced with NaHCO(3). Gel strength analysis indicated that bead strength decreased with increasing gas-forming agent from 9 to 4 N. Beads incorporating CaCO(3) exhibited significantly increased gel strength over control and NaHCO(3)-containing samples. Release characteristics of riboflavin as a model drug were studied in vitro. Release rate of riboflavin increased proportionally with addition of NaHCO(3). However, increasing weight ratios of CaCO(3) did not appreciably accelerate drug release. The results of these studies indicate that CaCO(3) is superior to NaHCO(3) as a gas forming agent in alginate bead preparations. The enhanced buoyancy and sustained release properties of CaCO(3)-containing beads make them an excellent candidate for floating drug dosage systems (FDDS).

HLA class II allele and haplotype frequencies in Koreans based on 107 families

We have investigated the distribution of HLA class II alleles and haplotypes in 107 Korean families (207 parents and 291 children) for the HLA-DRB1, DRB3/B4/B5, DQA1, DQB1 and DPB1 loci. Numbers of alleles observed for each locus were DRB1: 25, DQA1: 14, DQB1: 15, and DPB1: 13. Only two to three alleles were observed for the DRB3 (*0101, *0202, *0301), DRB4 (*0103, * 0103102 N), and DRB5 (*0101, *0102) loci. These alleles showed strong associations with DRB1 alleles: DRB3*0101 with DRB1*1201, *1301 and *1403; DRB3*0301 with DRB1*1202 and *1302; DRB3*0202 with DRB1*0301, *1101, *1401 and *1405; DRB5*0101 and *0102 were exclusively associated with DRB1*1501 and *1502, respectively. The seven most common DRB1-DQB1 haplotypes of frequencies > 0.06 accounted for 52% of the total haplotypes. These haplotypes were exclusively related with the seven most common DRB1-DRB3/B4/B5-DQA1-DQB1 haplotypes: DRB1*1501-DRB5*0101-DQA1*0102-DQB1*0602 (0.085), DRB1*0405-DRB4*0103-DQA1*0303-DQB1*0401 (0.082), DRB1*09012-DRB4*0103-DQA1*0302-DQB1*03032 (0.082), DRB1*0101-DQA1*0101-DQB1*0501 (0.075), DRB1*0701-DRB4*0103-DQA1*0201-DQB1*0202 (0.065), DRB1*0803-DQA1*0103-DQB1*0601 (0.065), and DRB1*1302-DRB3*0301-DQA1*0102-DQB1*0604 (0.065). When these haplotypes were extended to the DPB1 locus, much diversification of haplotypes was observed and only one haplotype remained with a frequency of > 0.06: DRB1*0405-DRB4*0103-DQA1*0303-DQB1*0401-DPB1*0501 (0.062). Such diversification would have resulted from cumulated events of recombination within the HLA class II region, and the actual recombination rate observed between the HLA-DQB1 and DPB1 loci was 2.3% (10/438 informative meioses, including 2 recombinants informative by analysis of TAP genes). Comparison of the distribution of DRB1-DQB1 haplotypes with other populations revealed that Koreans are closest to Japanese people. However, Koreans share a few haplotypes with white people and Africans, which are rare in Japanese: DRB1*0701-DQB1*0202 and DRB1*1302-DQB1*0609. The results obtained in this study will provide useful information for anthropology, organ transplantation and disease association studies.

Effects of sex hormones on Na+/glucose cotransporter of renal proximal tubular cells following oxidant injury

It was reported that reactive oxygen metabolites play an important role in the pathogenesis of several renal diseases including glomerulonephritis, ischemia and acute tubular necrosis. However, the effect of oxidants and protective effect of sex steroid hormones on Na+/glucose cotransporter of renal proximal tubular cells is not yet elucidated. In the present study, we examined the effect of sex steroid hormones against tert-butyl hydroperoxide (t-BHP)-induced alteration of Na+/glucose cotransporter activity in primary cultured rabbit renal proximal tubule cells (PTCs). t-BHP inhibited alpha-methyl-D-glucopyranoside (alpha-MG) uptake in a dose-dependent manner. t-BHP-induced inhibition of alpha-MG uptake was due not to Km but to the decrease of Vmax. 0.5 mM t-BHP-induced inhibition of alpha-MG uptake was significantly blocked by estradiol-17beta, but not by progesterone and testosterone. This protective effect was not blocked by estrogen receptor antagonist or transcription and translation inhibitor. In addition, 0.5 mM t-BHP increased [3H]-arachidonic acid (AA) release and Ca2+ uptake. These effects of t-BHP were also significantly blocked by estradiol-17beta, but not by progesterone and testosterone. Protective efficacy of estradiol-17beta on t-BHP-induced inhibition of alpha-MG uptake is exhibited between antioxidants and iron chelators. In conclusion, estradiol-17beta, but not progesterone and testosterone, partially prevented t-BHP-induced inhibition of alpha-MG uptake through its antioxidant activity dependent upon phenol structures and inhibition of AA release and Ca2+ influx.

Molecular cloning and expression of a cDNA encoding the luciferase from the firefly, Pyrocoelia rufa

To clone a cDNA encoding the luciferase of the firefly, Pyrocoelia rufa, we have constructed a cDNA library and isolated the luciferase gene using PCR with gene specific primers. Sequence analysis of the cDNA encoding the luciferase of P. rufa revealed that the 1647 bp cDNA has an open reading frame of 548 amino acid residues. The deduced amino acid sequences of the luciferase gene of P. rufa showed 98.9% homology to that of P. miyako. Phylogenetic analysis further confirmed the deduced amino acid sequences of the P. rufa luciferase gene belonged to the same subfamily, Lampyrinae. Southern blot analysis suggested possible presence of the P. rufa luciferase gene as a single copy and Northern blot analysis confirmed light organ-specific expression pattern at the transcriptional level. The cDNA encoding the luciferase of P. rufa was expressed as a 69 kDa band in baculovirus-infected insect cells and the recombinant baculovirus-infected cell extracts emitted luminescence in the luciferase activity assay.