Induction of glycation suppresses glucokinase gene expression in HIT-T15 cells

AIMS/HYPOTHESIS

Chronic hyperglycaemia in patients with Type II (non-insulin-dependent) diabetes mellitus often leads to a decline in glucose-responsive insulin secretion from pancreatic beta cells, a phenomenon called glucose toxicity. Upon hyperglycaemia, glycation reaction occurs in the beta cells and induces oxidative stress. To understand the molecular basis of the beta-cell glucose toxicity, we investigated the possible effects of glycation on the expression and enzymatic activity of glucokinase, which plays a crucial part in glucose-responsive insulin secretion.

METHODS

Glycation and reactive oxygen species were induced in HIT-T15 cells by treatment with D-ribose and effects on glucokinase gene transcription, glucokinase protein amount, glucose phosphorylation activity, and DNA-binding activities of putative glucokinase gene transcription factors were evaluated.

RESULTS

When glycation was induced in HIT-T15 cells, the activity of the human glucokinase gene beta-cell-type promoter was suppressed substantially (83% reduction at 60 mmol/l D-ribose). Also, similar reductions in mRNA and protein amounts of glucokinase and in the Vmax of its enzymatic activity were observed. In agreement with the reduction in the promoter activity, the two major transcription factors of the glucokinase gene, the Pal-binding factor and PDX-1, reduced their binding to their target sequences in the glucokinase gene promoter in glycation-induced HIT cells. Because these effects of D-ribose were counteracted by aminoguanidine or N-acetylcysteine, reactive oxygen species, generated by the glycation reaction, appears to be involved in the phenomena.

CONCLUSION/INTERPRETATION

The induction of the glycation reaction, which is known to occur in pancreatic beta cells in chronic hyperglycaemia, suppresses the glucokinase gene transcription and its enzymatic activity. Thus, hyperglycaemia-dependent inhibition of glucokinase activity could in part explain beta-cell glucose toxicity.

Impaired diurnal cardiac autonomic function in subjects with type 2 diabetes

OBJECTIVE

To assess diurnal cardiac sympathetic and parasympathetic nerve functions in diabetic subjects with variable diabetic neuropathy.

RESEARCH DESIGN AND METHODS

Frequency domain analysis of 24-h Holter ECG was done for 132 diabetic subjects (84 without any symptomatic neuropathy; 37 with only symptomatic peripheral neuropathy; 11 with symptomatic autonomic neuropathy) and 57 normal volunteers to calculate the low frequency (LF) component representing the beta-adrenoceptor function and the high frequency (HF) component representing the cardiac parasympathetic nerve function.

RESULTS

Cardiac LF and HF components in diabetic subjects without peripheral neuropathy showed values comparable to those of normal volunteers and a similar circadian rhythm. Diabetic subjects with peripheral neuropathy or autonomic neuropathy showed significantly depressed LF and HF components and loss of the circadian rhythm of LF and HF components compared with diabetic subjects without neuropathy. Impairment of the LF component in the afternoon could be accounted for by the duration of diabetes and elevated HbA1c level. Impairment of the HF component at night could be accounted for by the duration of diabetes but not an elevated HbA1c level.

CONCLUSIONS

These data indicated that diabetic subjects with peripheral neuropathy and diabetic subjects with symptomatic autonomic neuropathy, but not diabetic subjects without neuropathy, showed a marked decrease in cardiac sympathetic and parasympathetic nerve functions and loss of circadian rhythm.

Identification of a portable repression domain and an E1A-responsive activation domain in Pax4: a possible role of Pax4 as a transcriptional repressor in the pancreas

Pax4 is a paired-domain (PD)-containing transcription factor which plays a crucial role in pancreatic beta/delta-cell development. In this study, we characterized the DNA-binding and transactivation properties of mouse Pax4. Repetitive rounds of PCR-based selection led to identification of the optimal DNA-binding sequences for the PD of Pax4. In agreement with the conservation of the optimal binding sequences among the Pax family transcription factors, Pax4 could bind to the potential binding sites for Pax6, another member of the Pax family also involved in endocrine pancreas development. The overexpression of Pax4 in HIT-T15 cells dose dependently inhibited the basal transcriptional activity as well as Pax6-induced activity. Detailed domain mapping analyses using GAL4-Pax4 chimeras revealed that the C-terminal region of Pax4 contains both activation and repression domains. The activation domain was active in the embryonic kidney-derived 293/293T cells and embryonal carcinoma-derived F9 cells, containing adenoviral E1A protein or E1A-like activity, respectively but was inactive or very weakly active in other cells including those of pancreatic beta- and alpha-cell origin. Indeed, the exogenous overexpression of type 13S E1A in heterologous cell types could convert the activation domain to an active one. On the other hand, the repression domain was active regardless of the cell type. When the repression domain was linked to the transactivation domain of a heterologous transcription factor, PDX-1, it could completely abolish the transactivation potential of PDX-1. These observations suggest a primary role of Pax4 as a transcriptional repressor whose function may involve the competitive inhibition of Pax6 function. The identification of the E1A-responsive transactivation domain, however, indicates that the function of Pax4 is subject to posttranslational regulation, providing further support for the complexity of mechanisms that regulate pancreas development.

Beneficial effects of antioxidants in diabetes: possible protection of pancreatic beta-cells against glucose toxicity

Oxidative stress is produced under diabetic conditions and possibly causes various forms of tissue damage in patients with diabetes. The aim of this study was to examine the involvement of oxidative stress in the progression of pancreatic beta-cell dysfunction in type 2 diabetes and to evaluate the potential usefulness of antioxidants in the treatment of type 2 diabetes. We used diabetic C57BL/KsJ-db/db mice, in whom antioxidant treatment (N-acetyl-L-cysteine [NAC], vitamins C plus E, or both) was started at 6 weeks of age; its effects were evaluated at 10 and 16 weeks of age. According to an intraperitoneal glucose tolerance test, the treatment with NAC retained glucose-stimulated insulin secretion and moderately decreased blood glucose levels. Vitamins C and E were not effective when used alone but slightly effective when used in combination with NAC. No effect on insulin secretion was observed when the same set of antioxidants was given to nondiabetic control mice. Histologic analyses of the pancreases revealed that the beta-cell mass was significantly larger in the diabetic mice treated with the antioxidants than in the untreated mice. As a possible cause, the antioxidant treatment suppressed apoptosis in beta-cells without changing the rate of beta-cell proliferation, supporting the hypothesis that in chronic hyperglycemia, apoptosis induced by oxidative stress causes reduction of beta-cell mass. The antioxidant treatment also preserved the amounts of insulin content and insulin mRNA, making the extent of insulin degranulation less evident. Furthermore, expression of pancreatic and duodenal homeobox factor-1 (PDX-1), a beta-cell-specific transcription factor, was more clearly visible in the nuclei of islet cells after the antioxidant treatment. In conclusion, our observations indicate that antioxidant treatment can exert beneficial effects in diabetes, with preservation of in vivo beta-cell function. This finding suggests a potential usefulness of antioxidants for treating diabetes and provides further support for the implication of oxidative stress in beta-cell dysfunction in diabetes.

Identification of oxidative stress-regulated genes in rat aortic smooth muscle cells by suppression subtractive hybridization

A suppression subtractive hybridization technique was used to identify reactive oxygen species (ROS)-regulated genes in rat vascular smooth muscle cells. Three genes out of 89 clones, identified as fibronectin, p105 coactivator and ECA39, showed increased expression after treatment with H(2)O(2). The mRNA expressions of these three genes were induced in a time- and dose-dependent manner, independent of protein kinase C activation. Immunohistochemical staining showed that the p105 coactivator expression was markedly induced in the neointima of balloon-injured rat carotid arteries. These results suggest that ROS may play an important role in the development of atherosclerosis by regulating the gene expressions we identified in this study.

The role of surgery in renal cell carcinoma with solitary metachronous metastasis to contralateral adrenal gland

We report a case of renal cell carcinoma with solitary metachronous metastasis to contralateral adrenal gland occurring 9 months after radical nephrectomy. The patient was treated with a contralateral adrenalectomy and is alive for 87 months. The literature was reviewed and 5-year survival of solitary metachronous metastasis to contralateral adrenal gland was 60%. Follow-up duration of our case was the longest in the literature. It is suggested that the solitary contralateral adrenal gland metastasis of renal cell carcinoma should be resected since there is no effective treatment of metastatic renal cell carcinoma. Good prognosis may be then and the good be expected.

Pilot study on the effect of a mouthrinse containing silver zeolite on plaque formation

A double-blind cross-over study was performed to evaluate the inhibitory activity of silver zeolite (SZ) mouthrinse on plaque formation. Eleven dental students participated in this study. SZ mouthrinse was prepared by suspending SZ powder into phosphate-buffered saline (PBS) at a concentration of 3% (w/w). Type-A zeolite was used as a placebo. Before the experiment, the subjects were rendered plaque-free by professional prophylaxis. They then suspended any oral hygiene for five days, during which time they rinsed with either SZ or type-A zeolite mouthrinse twice a day. SZ significantly reduced plaque formation compared to the placebo (p < 0.05), suggesting that silver ions released from the SZ inhibited plaque formation.

Insulin resistance contributes to carotid arterial wall thickness in patients with non-insulin-dependent-diabetes mellitus

The aim of this study was to clarify whether insulin resistance contributes to atherosclerosis in patients with non-insulin-dependent diabetes mellitus (NIDDM). Fifty-three NIDDM patients (36 males and 17 females, 53+/-10 years old (mean+/-SD)) were studied. As an index of atherosclerosis, we measured the average thickness (IMT) as well as basal thickness excluding the maximum thickness and the height of the maximum thickness of the carotid artery wall. Euglycemic hyperinsulinemic glucose clamp was conducted for 90 min to evaluate average glucose infusion rate (GIR) as an index of insulin sensitivity in the peripheral tissues. For another 180 min after intake of oral glucose load with 0.3 g/kg, the euglycemic hyperinsulinemic clamp was continued to measure ratio of splanchnic glucose uptake (SGU) as an index of insulin sensitivity of the liver. The patients were separated into three activity groups according to the grade of their leisure-time physical activity. GIR (r = -0.32, p < 0.05) but not SGU (r=0.139) showed a significant inverse relationship with IMT. Multivariant regression analysis indicated that age and total cholesterol remain as independent risk factors for basal thickness and GIR as only independent risk factor for the height of the maximum thickness. Paralleling the degrees of habitual exercise (low, moderate, and high active group), GIR was higher (6.19+/-1.02, 6.38+/-1.38, 7.44+/-1.80, respectively) and IMT was lower (1.34+/-0.33 mm, 1.20+/-0.31 mm, and 1.12+/-0.29 mm, respectively) in male NIDDM as well as in female NIDDM. These data suggest that insulin resistance in the peripheral tissues but not the splanchnic tissues may independently contribute to carotid arterial wall thickness and especially to plaque lesion, and that habitual exercise might reduce insulin resistance leading to attenuation of atherosclerosis.

Metabolic suppression of platelet-type 12-lipoxygenase in human uterine cervix with invasive carcinoma

Several types of lipoxygenases with various functions occur in mammalian cells. Although the presence of 12-lipoxygenase activity has been reported in uterine tissues, neither its type nor its biological functions have yet been established. Moreover, the putative role of uterine 12-lipoxygenase in cervical cancer has not been addressed before. Homogenates of uterine tissues from women without cancer and from patients with invasive cervical carcinoma were incubated with (1-(14)C)-arachidonic acid under various conditions and the labelled reaction products were analyzed both by thin-layer chromatography and by high-pressure liquid chromatography. 12-Lipoxygenase protein was estimated by Western blot using anti-serum against recombinant human platelet-type 12-lipoxygenase. Highest concentrations and activities of 12-lipoxygenase were found in the exocervix. The formation of 12S-hydroxy-5Z,8Z,10E, 14Z-eicosatetraenoic acid (12-HETE) was stimulated by micromolar concentrations of 13S-hydroperoxy-9Z,11E-octadecadienoic acid, suggesting metabolic control of the 12-lipoxygenase activity via the hydroperoxide tone. Immunohistochemical investigation revealed that the enzyme is mainly located in the squamous epithelium, and is of platelet-type. Significantly lower values for the 12-HETE formation were found in samples from patients with invasive cervical carcinoma, whereas the amount of immunochemically detectable 12-lipoxygenase protein was unaltered. At the same time the expression levels of the bcl-2 gene were enhanced. Thus, it is concluded that during carcinogenesis the hydroperoxide-reducing capacity of the uterine cervix tissue is enhanced, possibly mediated by bcl-2 protein, and in turn metabolically suppresses the 12-lipoxygenase activity. Furthermore, the data suggest an anti-carcinogenic action of 12-lipoxygenase in human cervix, in contrast to its reported pro-carcinogenic action in breast cancer.

Impaired splanchnic and peripheral glucose uptake in liver cirrhosis

BACKGROUND/AIM

Patients with liver cirrhosis are insulin-resistant and frequently glucose-intolerant. Although peripheral glucose uptake has been shown to be impaired in liver cirrhosis, little is known about the significance of splanchnic (hepatic) glucose uptake after oral glucose load.

METHODS/RESULTS

We performed an oral glucose tolerance test and euglycemic hyperinsulinemic clamp with oral glucose load for eight patients with liver cirrhosis and eight patients with chronic active hepatitis. The patients with liver cirrhosis had higher plasma glucose levels 2 h after glucose load than those with chronic active hepatitis (228+/-22 mg/dl vs. 102+/-9 mg/dl, p<0.01). Using the euglycemic hyperinsulinemic clamp with oral glucose load, we simultaneously measured peripheral and splanchnic glucose uptake. Peripheral glucose uptake in liver cirrhosis was 6.1+/-0.7 mg x kg(-1) x min(-1), which was lower than that in healthy volunteers (10.5+/-0.9 mg x kg(-1) x min(-1), p<0.05) and in chronic active hepatitis (8.4+/-0.3 mg x kg(-1) x min(-1), p<0.05). Furthermore, splanchnic glucose uptake in liver cirrhosis was much lower (20.1+/-3.4%) than in healthy volunteers (36.0+/-4.0%, p<0.05) and in chronic active hepatitis (37.2+/-3.1%, p<0.05).

CONCLUSION

These results suggest that glucose intolerance in patients with liver cirrhosis is caused by a defect of the glucose uptake of both splanchnic and peripheral tissues.

Oxidative stress induces p21 expression in pancreatic islet cells: possible implication in beta-cell dysfunction

AIMS/HYPOTHESIS

Prolonged poor glycaemic control in patients with Type II (non-insulin-dependent) diabetes mellitus often causes pancreatic beta-cell dysfunction accompanied by decreases in insulin biosynthesis and beta-cell proliferation. This is well known as a clinical concept called glucose toxicity. Whereas oxidative stress is provoked under diabetic conditions, we examined the possible implication of cyclin-dependent kinase (Cdk) inhibitor p21 (WAF1/CIP1/Sdi1) in beta-cell dysfunction mediated by oxidative stress.

METHODS

Oxidative stress was induced in isolated rat pancreatic islet cells by treatment with H(2)O(2) and mRNA expression of p21 and insulin was examined by northern blot analyses. Also, the expression of p21 and insulin mRNA was examined in Zucker diabetic fatty rat. In islet cells p21 was overexpressed using adenovirus and its effect on insulin gene transcription was examined.

RESULTS

When oxidative stress was charged on isolated rat pancreatic islet cells, p21 mRNA expression was induced whereas insulin mRNA was decreased. Also, when diabetes developed in Zucker diabetic fatty rats, p21 expression was induced and the insulin mRNA expression was reduced. As support for the implication of p21 in impairment of beta-cell function, the p21 overexpression in the islet cells suppressed the insulin gene transcription.

CONCLUSIONS/INTERPRETATION

The expression of cyclin-dependent kinase inhibitor p21, which can be induced by oxidative stress, increases in pancreatic islet cells upon development of diabetes. By suppressing cell proliferation and insulin biosynthesis, the p21 induction is likely to be implicated in the beta-cell glucose toxicity.

Development of a hepatocyte-specific prostaglandin E(1) polymeric prodrug and its potential for preventing carbon tetrachloride-induced fulminant hepatitis in mice

A polymeric prodrug of prostaglandin E(1) (PGE(1)) was synthesized using galactosylated poly(L-glutamic acid hydrazide) (Gal-HZ-PLGA) as a biodegradable and targetable carrier to hepatocytes. Poly(L-glutamic acid hydrazide) was prepared by reacting poly(gamma-benzyl-L-glutamate) with hydrazine monohydrate, followed by reaction with 2-imino-2-methoxyethyl-1-thiogalactosides to obtain Gal-HZ-PLGA after i.v. injection. (111)In-labeled galactosylated poly(L-glutamic acid hydrazide) ((111)In-Gal-HZ-PLGA) rapidly accumulated in the liver in a dose-dependent manner, whereas (111)In-poly(L-glutamic acid hydrazide) did not, indicating the involvement of a galactose-specific mechanism in the uptake of (111)In-Gal-HZ-PLGA. Fractionation of liver cells revealed that (111)In-Gal-HZ-PLGA was preferentially taken up by liver parenchymal cells. After being taken up by the liver, (111)In-Gal-HZ-PLGA was gradually degraded, and radioactive metabolites with low molecular weight were detected within 10 min after injection. Then, PGE(1) or [(3)H]PGE(1) was coupled to Gal-HZ-PLGA via a hydrazone bond under mild conditions to obtain PGE(1) conjugate. After i.v. injection, [(3)H]PGE(1) conjugate was rapidly taken up by the liver (more than 80% of the dose). After injection of the conjugate, (3)H radioactivity remained in the liver, representing about 70% of the dose, even at 24 h, whereas little radioactivity remained in the organ at 1 h after the injection of free [(3)H]PGE(1). Finally, its pharmacological activity was examined in mice with fulminant hepatitis induced by peritoneal injection of carbon tetrachloride. The i.v. injection of PGE(1) conjugate at a dose of 1 mg (0.074 mg PGE(1))/kg effectively inhibited the increase of plasma glutamic pyruvic transaminase activity, whereas twice this dose (0.15 mg/kg) of free PGE(1) had little effect. These results suggest that the PGE(1) conjugate is an excellent polymeric prodrug of PGE(1) for hepatitis therapy.

Polymorphism in the tumor necrosis factor B gene is associated with Palmoplantar pustulosis

We investigated the allele and genotype distribution of a polymorphism of the tumor necrosis factor (TNF) B gene and the frequency of HLA-DR9 in 49 patients with Palmoplantar pustulosis (PPP) and 51 healthy controls. We found that the frequency of TNFB2 in the PPP patients was significantly higher than that in the controls. Furthermore, the DR9-TNFB2 haplotype was significantly more frequent in the PPP patients (P=0.0045). These results suggest that TNFB2 may confer susceptibility to PPP.

Overexpression of the aldose reductase gene induces apoptosis in pancreatic beta-cells by causing a redox imbalance

To determine the role of the polyol metabolizing pathway under hyperglycemic conditions, the effects of aldose reductase (AR) on the cellular functions of pancreatic beta-cells were examined. Stable transfectants of rat AR cDNA were obtained with a pancreatic beta-cell line, HIT, in which a negligible amount of AR was originally expressed. Overproduction of AR triggered DNA fragmentation, as judged with the TUNEL method and agarose gel electrophoresis. Morphological analysis by electron microscopy also clearly showed apoptosis of the AR-overexpressing HIT cells. Induction by interleukin-1beta of gene expression such as those of an inducible form of nitric oxide synthase (NOS-II) and Mn-superoxide dismutase (Mn-SOD), was much lower in the transfectants than in the control cells, while the expression of constitutively expressed genes such as those for Cu,Zn-superoxide dismutase and insulin was not changed. The susceptibility to interleukin-1beta stimulation of the expression of the NOS II and Mn-SOD genes was due to suppressed NF-kappaB activity, which is essential for the expression of these genes. In addition, the intracellular NADPH/NADP+ ratio was considerably lower in the AR-transfected cells than in control cells. Thus, the overexpression of AR in pancreatic beta-cells induced apoptosis that may be caused by a redox imbalance.

Severe impairment of B cell function in lpr/lpr mice expressing transgenic Fas selectively on B cells

Transgenic lpr/lpr mice expressing functional Fas selectively on B cells were produced in an attempt to elucidate the role of Fas on B cells in the regulation of autoantibody production. The homozygous lpr/lpr mice carrying the transgene did not produce anti-double-stranded DNA antibodies throughout their lives, whereas the development of abnormal lpr T cells (double negative, B220(+)) was not suppressed. Further analyses, however, revealed that the expression of the transgenic Fas on B cells of lpr/lpr homozygous mice resulted in severe impairment of the B cell function. The defect was characterized by a decrease in the number of mature peripheral B cells, a reduction in the serum Ig level and the total failure of B cells to mount antibody responses to stimulations of T-dependent as well as T-independent antigens. Such a defect was prominent only when the transgene was expressed on the lpr/lpr homozygous background. On the contrary, B cells of the transgenic lpr/lpr mice were shown to be capable of producing Ig when stimulated with anti-CD40 in the presence of IL-4 and IL-5. Furthermore, lpr/lpr T cells showed enhanced non-specific cytolytic activity. These observations suggested that the observed B cell defect was probably attributable to the destruction of activated B cells expressing transgenic Fas by aggressive lpr/lpr T cells.

Genetic dissection of "OLETF," a rat model for non-insulin-dependent diabetes mellitus: quantitative trait locus analysis of (OLETF x BN) x OLETF

To identify genetic determinants relevant to non-insulin-dependent diabetes mellitus (NIDDM), we performed a genome-wide analysis for quantitative trait loci (QTLs) using 359 backcross progeny of the Otsuka Long-Evans Tokushima Fatty (OLETF) rat. The OLETF strain is a well-studied animal model of obese NIDDM, with features of hyperinsulinemia, hyperglycemia, insulin resistance, and abundant abdominal fat. Our extensive genomic scanning with 218 markers revealed nine significant QTLs, including a strong determinant of obesity on chromosome 1 (Dmo1: LOD = 13.99, for body weight). Two highly significant QTLs for glucose homeostasis were found, one on chromosome 1 (Dmo4 LOD = 7.16, for postprandial glucose level) and the other on chromosome X (Dmo11/Odb1: LOD = 7.81, for postprandial glucose level). These data are comparable to results of our previous studies of the OLETF rat.

A radiation hybrid map of the rat genome containing 5,255 markers

A whole-genome radiation hybrid (RH) panel was used to construct a high-resolution map of the rat genome based on microsatellite and gene markers. These include 3,019 new microsatellite markers described here for the first time and 1,714 microsatellite markers with known genetic locations, allowing comparison and integration of maps from different sources. A robust RH framework map containing 1,030 positions ordered with odds of at least 1,000:1 has been defined as a tool for mapping these markers, and for future RH mapping in the rat. More than 500 genes which have been mapped in mouse and/or human were localized with respect to the rat RH framework, allowing the construction of detailed rat-mouse and rat-human comparative maps and illustrating the power of the RH approach for comparative mapping.

Clinical significance of mdm2 and p53 expression in bladder cancer. A comparison with cell proliferation and apoptosis

BACKGROUND

Clinical significance of immunohistochemically detectable level of p53 protein has been reported, but with some limitation as a prognosticator of bladder cancer patients. Whether or not simultaneous evaluation of mdm2 and p53 expression in bladder cancer exceed the prognostic significance of conventional histological findings, cell proliferation markers and apoptotic parameters remains unclear.

MATERIALS AND METHODS

The paraffin-embedded materials taken from 84 patients with transitional cell carcinoma of the bladder who were treated with total cystectomy were used in this study. Immunostainings of p53 protein, mdm2 protein and Ki67 antigen were performed using monoclonal antibodies (clone DO7, clone 1B10 and clone MIB1, respectively). In addition, the apoptotic cells were determined using a terminal deoxynucleotidyl transferase (TdT) mediated dUTP biotin nick end labeling (TUNEL) technique. The results were quantitatively evaluated using a CAS 200 Image Analyzer (Cell Analysis System, Elmhurst, Ill., USA) and were compared with histological findings and clinical course.

RESULTS

The mean values of mdm2 expression, p53 immunoreactivity, Ki67 expression and apoptotic index were 19.2, 20.5, 22.4 and 0.96%, respectively. Histological grade and pT category were significantly positively correlated with 53 immunoreactivity (p < 0.05 and p < 0.05, respectively), Ki67 expression (p < 0.005 and p < 0.0001, respectively) and apoptotic index (p < 0.01 and p < 0.0001, respectively), while both were not correlated with mdm2 expression. Using univariate analysis, the prognostic relevance for both survival and disease progression was noted in histological grade, pT category, p53 expression, Ki67 index and apoptotic index, whereas it was not in mdm2 expression. However, when analyzing the simultaneous evaluation of mdm2 and p53 expression (mdm2-p53 category), the relationship of the mdm2-p53 category with Ki67 expression and apoptotic index showed a statistical significance and a borderline significance (p = 0.0085 and p = 0.0652, respectively). In addition, the patients with both mdm2(-) and p53(-) showed a significant better prognosis as compared with either counterpart of mdm2-p53 category (p < 0.05 for both). Multivariate analysis revealed only pT category and mdm2-p53 category as independent factors for both disease progression and survival.

CONCLUSIONS

Clinical significance of simultaneous evaluation of mdm2 and p53 immunostaining proved to be superior over that of cell proliferation and/or apoptotic markers when elucidating the biological characteristics of bladder cancer.

A calculation method for the range of occluding phase at the lower incisal point during chewing movements using the curved mesh diagram of mandibular excursion (CMDME)

The purpose of this study was to develop a method for calculating the range of the occluding phase in chewing movements. In this study, we defined 'range' as the distance of the movement at the lower incisal point while the mandible moves with tooth contact. First, mandibular excursions were measured using an opto-electronic movement analysis system, which can measure mandibular movement with six degrees-of-freedom at a sampling frequency of 100 Hz. With use of this measurement data, the curved mesh diagram of mandibular excursion (CMDME) previously reported was made. Then, chewing movements were measured using the same analysis system. The movements were separated into their component chewing cycles. Finally, we calculated the distance between each cycle and the CMDME. The occluding range of our subject was 0.4 mm at the closing phase and 3.4 mm at the opening phase. These results suggest that tooth contact occurs during chewing movement and demonstrate that the range of the occluding phase for the opening and closing phases of a subject can be calculated without morphological data from a dental cast.

Disposition characteristics of glycosylated poly(amino acids) as liver cell-specific drug carrier

Potentials of glycosylated poly(amino acids) as carriers of drugs and/or polynucleotides to the liver were studied in mice in detail. Poly-L-glutamic acid (PLGA) and poly-L-lysine (PLL) were selected as carrier backbones and modified with 2-imino-2-methoxyethyl 1-thiogalactoside or mannoside to obtain galactosylated and mannosylated derivatives. After intravenous injection in mice at a dose of 1 mg/kg, Gal-PLGA and Man-PLGA were selectively taken up by the liver parenchymal cells (PC) and liver nonparenchymal cells (NPC), respectively. Moreover, the uptake of Gal-PLGA and Man-PLGA by the liver were significantly inhibited by the presence of Gal-BSA and Man-BSA, respectively. On the other hand, PLL was targeted to the liver without glycosylation. However, Gal-PLL and Man-PLL showed higher accumulation in the liver than unmodified PLL. Although Gal-PLL and Man-PLL showed different distribution between PC and NPC from that of PLL, the effect of the modifications was less pronounced than the cases of PLGA derivatives. In addition, these glycosylated poly(amino acids) investigated, regardless of the type of amino acid or the sugar grafted, were rapidly degraded to be eluted in the low molecular weight fractions in a gel filtration chromatography. These results suggest that glycosylated PLGAs can be useful carriers of low molecular drugs to the liver cells through conjugation, while glycosylated PLLs could be targetable carriers to the cells after the reduction of their cationic charge by complex formation with polynucleotides.

[Allogeneic peripheral blood stem cell transplantation in an elderly patient with myelodysplatic syndrome with myelofibrosis]

Allogeneic peripheral blood stem cell transplantation (Allo-PBSCT) has in recent years become an alternative to allogeneic bone marrow transplantation because it facilitates rapid hematopoietic reconstitution without an increase in the incidence of severe graft-versus-host disease (GVHD). We report on a 61-year-old man with myelodysplastic syndrome (MDS) and myelofibrosis who received an allo-PBSCT from his HLA-matched 68-year-old brother. The preparative regimen consisted of busulfan and cyclophosphamide. Cyclosporin A and methotrexate were administered for GVHD prophylaxis. The donor was treated with granulocyte colony-stimulating factor (G-CSF) at a dose of 10 micrograms/kg/day subcutaneously for 4 consecutive days. A preparation of 4.04 x 10(6) CD34+ cells/kg recipient weight was collected in a single apheresis and infused immediately. Engraftment times to a neutrophil count greater than 500/microliter and platelet count greater than 2.0 x 10(4)/microliter were 15 days each. Acute GVHD of grade II developed, but was resolved with methylprednisolone. However, the patient died of thrombotic microangiopathy 97 days after his allo-PBSCT. Administration of G-CSF and apheresis in the donor were feasible and well tolerated. Allo-PBSCT may result in earlier engraftment and be especially beneficial to elderly patients with MDS.

The development of autoimmune inflammatory arthropathy in mice transgenic for the human T cell leukemia virus type-1 env-pX region is not dependent on H-2 haplotypes and modified by the expression levels of Fas antigen

Previously, we reported that human T cell leukemia virus type-1 env-pX region-introduced transgenic (pX-Tg) mice develop an inflammatory polyarthropathy. Although autoimmune pathogenesis was suggested, the detailed mechanisms remain to be elucidated. In this report, we examined effects of the MHC and fas genes on the development of the disease. When pX-Tg mice were backcrossed with different inbred strains, the incidence of arthritis differed among strains; 64% and 72% in BALB/cAn (H-2d), 25% and 46% in C3H/HeN (H-2k), and 0% and 2% in C57BL/6J (H-2b) background at 3 and 6 months of age, respectively. Rheumatoid factor levels in the serum correlated with the susceptibility to the disease, whereas IL-1beta and MHC gene expression were similarly elevated in all of these strains, suggesting involvement of immune regulatory genes in this strain difference. However, introduction of the H-2d locus into C57BL/6J pX-Tg mice did not increase the incidence of arthritis, and substitution of the BALB/cAn H-2 locus with the H-2b did not decrease it. The results indicate that the H-2 locus is not the major determinant of the disease. Then, since previous study indicated a defect in Fas-mediated apoptosis of transgenic T cells, the effects of fas gene modification on the disease were examined. The incidence increased when these pX-Tg mice were crossed with lpr/lpr mice, while it decreased when crossed with fas-transgenic mice. These observations suggest that aberration of Fas-mediated apoptosis of peripheral lymphocytes, rather than negative selection in the thymus, is involved in the development of autoimmune arthropathy in pX-Tg mice.