Expression of the gene for a membrane-bound fatty acid receptor in the pancreas and islet cell tumours in humans: evidence for GPR40 expression in pancreatic beta cells and implications for insulin secretion

AIMS/HYPOTHESIS

G protein-coupled receptor 40 (GPR40) is abundantly expressed in pancreatic beta cells in rodents, where it facilitates glucose-induced insulin secretion in response to mid- to long-chain fatty acids in vitro. However, GPR40 gene expression in humans has not been fully investigated, and little is known about the physiological and pathophysiological roles of GPR40 in humans. The aim of this study, therefore, was to examine GPR40 expression and its clinical implications in humans.

METHODS

GPR40 mRNA expression in the human pancreas, pancreatic islets and islet cell tumours was analysed using TaqMan PCR.

RESULTS

GPR40 mRNA was detected in all human pancreases collected intraoperatively. It was enriched approximately 20-fold in isolated islets freshly prepared from the pancreases of the same individuals. The estimated mRNA copy number for the GPR40 gene in pancreatic islets was comparable to those for genes encoding sulfonylurea receptor 1, glucagon-like peptide 1 receptor and somatostatin receptors, all of which are known to be expressed abundantly in the human pancreatic islet. A large amount of GPR40 mRNA was detected in insulinoma tissues, whereas mRNA expression was undetectable in glucagonoma or gastrinoma. The GPR40 mRNA level in the pancreas correlated with the insulinogenic index, which reflects beta cell function (r=0.82, p=0.044), but not with glucose levels during the OGTT, the insulin area under the OGTT curve or the index for the homeostasis model assessment of insulin resistance (HOMA-IR).

CONCLUSIONS/INTERPRETATION

The present study provides evidence for GPR40 gene expression in pancreatic beta cells and implicates GPR40 in insulin secretion in humans.

Alpha 2 integrin +807 polymorphism in drug-induced gingival overgrowth

Alpha2 integrin on fibroblasts is reported to play an important role in the induction of drug-induced gingival overgrowth, which is characterized by excessive accumulation of type I collagen in gingival connective tissue. Silent polymorphism 807 T/C within the alpha2 integrin gene is associated with high/low alpha2 integrin expression. The aim of this study was to test the hypothesis that expression of alpha2 integrin 807 T/C polymorphism correlates with drug-induced gingival overgrowth. A case-control study comparing 136 subjects taking calcium channel blockers (72 with vs. 64 without drug-induced gingival overgrowth) demonstrated that the frequency of the +807 C allele was significantly higher in the case group than in the controls (odds ratio, 3.61; 95% confidence interval, 2.14 - 6.10; P < 0.05). The present findings suggest that the alpha2 +807 C allele is one of the genetic risk factors for drug-induced gingival overgrowth.

Ethyl esterification of docosahexaenoic acid in an organic solvent-free system with immobilized Candida antarctica lipase

Ethyl docosahexaenoate (EtDHA) is regarded as a potentially useful pharmaceutical substance on account of its beneficial physiological activities. We attempted the ethyl esterification of docosahexaenoic acid (DHA) in an organic solvent-free system using Candida antarctica lipase, which acts strongly on DHA and ethanol. Esterification of 88% was attained by shaking a mixture of DHA/ethanol (1:1, mol/mol) and 2 wt% immobilized C. antarctica lipase at 30 degrees C for 24 h. However, even in the presence of an excess amount of ethanol, the extent of esterification could not be raised above 90%. To attain a higher level of esterification, a two-step reaction was found to be effective. The first step was performed in a mixture of DHA/ethanol (1:1, mol/mol), and the reaction mixture was then dehydrated. In the second step, the resulting mixture was shaken at 30 degrees C for 24 h with 5 molar equivalents of ethanol against the remaining DHA using 2 wt% immobilized lipase. By means of this two-step procedure, 96% esterification was attained. Repetition of the first and second reactions showed that the immobilized lipase was reusable for at least 50 cycles. In addition, DHA remaining in the second-step reaction mixture was removed by a conventional alkali refining process, giving purified EtDHA with a high yield.

Enzymatic purification of polyunsaturated fatty acids

Polyunsaturated fatty acids (PUFAs) have various physiological functions. Of these, ethyl eicosapentaenoate is industrially purified and used as a medicine. Other PUFAs, such as docosahexaenoic acid (DHA), gamma-linolenic acid (GLA), and arachidonic acid (AA), are also expected to be used as pharmaceutical agents; however, their industrial purification processes have not been established. Because PUFAs are highly unstable against heat and oxidation, we attempted to purify them by taking advantage of their enzymatic reactions. When free fatty acids (FFAs) originating from PUFA-containing oil were selectively esterified with lauryl alcohol (LauOH) using a lipase acting on a desired PUFA very weakly, the PUFA was efficiently enriched in the FFA fraction. In addition, when selective alcoholysis of ethyl esters originating from PUFA-containing oil with LauOH was carried out, the PUFA ethyl ester (EtPUFA) was enriched to a desired purity in the unreacted ethyl ester fraction. These reaction mixtures contain LauOH, PUFA (EtPUFA), and lauryl esters, and their molecular weights are different from one another. Hence, PUFA or EtPUFA can be easily separated by conventional distillation. Selective esterification increased the purity of DHA, GLA, and n-6 PUFAs rich in AA to 91, 98, and 96 wt%, respectively. Selective alcoholysis was also effective for increasing the purity of ethyl docosahexaenoate to 90 wt%.

A randomized double blind placebo-controlled clinical trial of Hochuekkito, a traditional herbal medicine, in the treatment of elderly patients with weakness N of one and responder restricted design

OBJECTIVE

To evaluate the effects of Hochuekkito, a traditional Japanese and Chinese medicine, in the treatment of elderly patients with general weakness. To devise a suitable study design for assessing the clinical effectiveness of traditional herbal medicines.

METHODS

Fifteen elderly patients (mean +/- SD: age 78.4 +/- 7.8; m/f 3/12) participated in this study. A multicenter, prospective, randomized, double-blind, placebo-controlled study with N of one and responder restricted design was performed. After the run-in period, the patients were divided into responders and non-responders. Only responders were entered in the study, and were randomized into three groups: an active-placebo group, a placebo-active group and an active-active group. The study consisted of two 6-week terms with a 2-week washout period in between. We assessed the Short Form 36 Health Survey (SF-36) and Profile of Mood States (POMS) as an endpoint of quality of life (QOL). In addition, we assessed the biodefense status by measuring the natural killer cytolytic activity (NK activity), IL-2 producing activity of peripheral lymphocytes, lymphocyte proliferating activity and lymphocyte cell-surface antigens.

RESULTS

The physical component summary of the SF-36 analysis significantly improved in the Hochuekkito-treated group. Four components (A-H: anger-hostility, F: fatigue, T-A: tension-anxiety, C: confusion) out of six improved in the Hochuekkito-treated group in the POMS analysis. Lymphocyte proliferating activity improved in the Hochuekkito-treated group but not significantly. Concerning the surface antigens of peripheral lymphocytes, the population of CD3 positive cells and CD3CD4 double positive cells increased in the Hochuekkito-treated group.

CONCLUSION

We revealed that Hochuekkito improved the QOL and immunological status of elderly patients with weakness by randomized controlled trial. Our study design might be useful for assessing the efficacy of traditional herbal medicine in the future.

Severe hypertension after stellate ganglion block

Haemodynamic effects may occur after stellate ganglion block (SGB) arising from autonomic imbalance and local anaesthetic infiltration to barosensitive areas. We report seven patients who developed severe hypertension (systolic arterial pressure >200 mm Hg) after SGB in our pain clinic service. We postulate that diffusion of the local anaesthetic along the carotid sheath may produce vagal blockade causing unopposed sympathetic activity as a result of attenuation of the baroreceptor reflex. We recommend close monitoring of arterial pressure measurement in patients who received SGB.

Vasodilative effect of perillaldehyde on isolated rat aorta

The vasodilative effect of perillaldehyde, one of the major oil components in Perilla frutescens BRITTON, was studied using isolated rat aorta. Perillaldehyde at final concentrations of 0.01 to 1 mM showed dose-dependent relaxation of the aorta contracted by treatment with prostaglandin F2alpha or norepinephrine. Neither the presence of NG-nitro-L-arginine methyl ester nor removal of the aortic endothelium affected the vasodilatation, suggesting that perillaldehyde exerts a direct effect on vascular smooth muscle cells. The vasodilative effect of perillaldehyde was not inhibited by pretreatment with a beta-adrenergic receptor blocker (propranolol), an inhibitor of phosphodiesterase (theophylline), a delayed rectifier K+ channel blocker (tetraethylammonium chloride), or an ATP-sensitive K+ channel blocker (glibenclamide). However, perillaldehyde showed contrasting effects on vasodilatation of the aorta contracted by an influx of extracellular Ca2+ - perillaldehyde caused little vasodilatation on the aorta contracted by the Ca2+ ionophore A23187, while it inhibited the vasoconstriction induced by treatment with high-concentration K+, which dominantly opened the voltage-dependent Ca2+ channel. These results suggest that the vasodilative effect of perillaldehyde is derived from blocking the Ca2+ channels.

The effect of Juzen-taiho-to/TJ-48 on the expression of killer-cell immunoglobulin-like receptors (CD158a/b) on peripheral lymphocytes in vitro experiment

Juzen-taiho-to (TJ-48), a mixture of extracts from 10 medicinal herbs, has been used traditionally to treat patients with anemia, anorexia or fatigue. It is well known that the treatment of TJ-48 result in the decrease of patient's complaints, as well as the increase of NK cytolytic activity (NK activity) although its augmentation is not clear in the other kampo formula from the clinical viewpoint. To investigate its biological activities, such as the augmentation of NK activity, we analyzed the effects of TJ-48 on the expression of killer-cell immunoglobulin-like receptors (KIRs) in vitro experiment. The peripheral lymphocytes were incubated in medium alone, or medium containing TJ-48 or interleukin-2 (IL-2) plus TJ-48 at several concentrations for 48 h. After each incubation, cells were collected and their KIRs were detected by flow cytometry using monoclonal antibodies CD158a and CD158b. TJ-48 increased the populations of CD16+CD158a+ and CD16+CD158b+ cells in a dose-dependent manner. In contrast, CD16-CD158a/b+ cells did not increase. Additionally, the extract of TJ-48 enhanced the increase of KIRs expression induced by IL-2. These actions contribute to the augmentation of NK cytolytic activity by TJ-48, and might explain, in part, its antitumor effects which has been observed in vivo.

Autoantibodies directed against the protease inhibitor calpastatin in psoriasis

Psoriasis is believed to be a T cell-mediated autoimmune disease, but also exhibits autoantibody production. Calpastatin is an endogenous inhibitor of calpain, a ubiquitous protease that regulates inflammatory processes. Anti-calpastatin autoantibody was first identified as an autoantibody specific to rheumatoid arthritis, but has been also detected in other autoimmune diseases. In this study, we examined the presence and levels of anti-calpastatin antibody in 77 psoriasis patients by enzyme-linked immunosorbent assay. Compared with normal controls, psoriasis patients exhibited significantly elevated IgG anti-calpastatin antibody levels that were similar to those found in rheumatoid arthritis patients. Remarkably, IgG anti-calpastatin autoantibody in sera from psoriasis patients inhibited calpastatin activity. Calpain II expression was up-regulated in psoriasis skin lesions compared with normal skin while calpastatin expression was normal. The results of this study reveal the presence of anti-calpastatin autoantibody in psoriasis.

Effect of halothane on intercellular adhesion molecule-1 (ICAM-1) in melanoma cells

There have only been a few reports relating to the effect of inhalational anesthetics on the tumor cell morphology in cancer patients undergoing surgery. We hypothesized that some anesthetic agents might influence the spread of unresectable cancer cells and might additionally worsen the condition of the patient due to depressed host immune surveillance. We therefore evaluated the influence of halothane on tumor cell adhesion, which is closely linked to tumor cell metastasis. Human melanoma cells from SK-MEL-37 cell-line were exposed to 4% halothane for 3, 6, 12 or 24 hours, respectively. Furthermore, after 24 hours halothane exposure, they were incubated in a 5% CO2 atmosphere for 12 or 24 hours. The cells were then analyzed using a fluorescence flowcytometer and intercellular adhesion molecule-1 (ICAM-1) expression in SK-MEL-37 cells was quantified as the intensity of fluorescence of ICAM-1 expressed in 10,000 cells. ICAM-1 expression in cells exposed to halothane for 3, 6, 12 or 24 hours was lower than that of non-exposed cells and returned to control level after further incubation in 5% CO2 atmosphere for either 12 or 24 hours. We conclude that halothane might affect the progression of tumor cell metastasis in vitro.

Interleukin-6 (IL-6) − 373 A9T11 allele is associated with reduced susceptibility to chronic periodontitis in Japanese subjects and decreased serum IL-6 level

We investigated whether interleukin-6 (IL-6) gene polymorphisms could be associated with chronic periodontitis (CP) and serum IL-6 level. One hundred and twelve CP and 77 non-CP Japanese subjects were analyzed for IL-6 -597 (G/A), -572 (C/G), -373 (A(n)T(m)), -190 (C/T), and -174 (G/C) polymorphisms. We could only detect -572 and -373 polymorphisms and found that the frequency and carriage rate of the -373 A9T11 allele were significantly higher in non-CP subjects. Enzyme-linked immunosorbent assay confirmed that the -572 and -373 G[A9T11] haplotypes were associated with lower serum IL-6 level. These findings suggest that IL-6 -373 A9T11 allele could be associated with reduced susceptibility to CP among Japanese subjects and decreased serum IL-6 level.

Phase I clinical trial and pharmacokinetic evaluation of NK911, a micelle-encapsulated doxorubicin

NK911 is a novel supramolecular nanocarrier designed for the enhanced delivery of doxorubicin (DXR) and is one of the successful polymer micelle systems to exhibit an efficient accumulation in solid tumours in mice. The purpose of this study was to define the maximum-tolerated dose (MTD) and dose-limiting toxicities (DLTs) of NK911 and to evaluate its pharmacokinetic profile in man. NK911 was given intravenously to patients with solid tumours every 3 weeks using an infusion pump at a rate of 10 mg DXR equivalent min⁻¹. The starting dose was 6 mg DXR equivalent m⁻², and the dose was escalated according to the accelerated titration method. A total of 23 patients participated in this study. Neutropenia was the predominant haematological toxicity, and grade 3 or 4 neutropenia was observed at doses of 50 and 67 mg m⁻². Common nonhaematological toxicities were mild alopecia, stomatitis, and anorexia. In the dose identification part of the study, DLTs were observed at a dose of 67 mg m⁻² (grade 4 neutropenia lasting more than 5 days). Thus, this dosage level was determined to be the MTD. Infusion-related reactions were not observed in any cases. The C_5 min and area under the concentration curve parameters of NK911 exhibited dose-dependent characteristics. Among the 23 patients, a partial response was obtained in one patient with metastatic pancreatic cancer. NK911 was well tolerated and produced only moderate nausea and vomiting at myelosuppressive dosages. The recommended phase II dose was determined to be 50 mg m⁻² every 3 weeks.

Detection of circulating oesophageal squamous cancer cells in peripheral blood and its impact on prognosis

BACKGROUND

Many studies have attempted to detect cancer cells using the reverse transcription-polymerase chain reaction (RT-PCR) for specific mRNAs. None has examined the correlation between the presence of circulating oesophageal cancer cells in peripheral blood and long-term outcome.

METHODS

Blood samples were obtained on admission, and before, during and after operation from 70 patients with squamous oesophageal cancer who had complete clinicopathological records and who underwent curative oesophagectomy between June 1997 and June 2000. RT-PCR for mRNA encoding squamous cell carcinoma antigen (SCCA mRNA) was used to detect oesophageal cancer cells in peripheral blood.

RESULTS

Twenty-three patients (33 per cent) were positive for SCCA mRNA on admission and 17 of these patients developed recurrent disease. SCCA mRNA on admission correlated with the depth of tumour invasion (P < 0.001) and with venous invasion (P < 0.001). Eleven of 24 patients with a positive intraoperative result were positive for SCCA mRNA only during operation, of whom seven also developed recurrence.

CONCLUSION

RT-PCR for SCCA mRNA can detect oesophageal cancer cells in peripheral blood. The presence of such cells in blood samples obtained on admission or during operation is a useful predictor of outcome in patients with oesophageal squamous cell carcinoma.

Polymorphisms in the IL-6 receptor (IL-6R) gene: strong evidence that serum levels of soluble IL-6R are genetically influenced

We have investigated the association of the recently identified IL6R polymorphisms with the serum levels of soluble IL-6 receptor (sIL-6R). sIL-6R is generated by shedding of the membrane-bound receptor (IL-6Ralpha) or alternative mRNA splicing. In total, 115 healthy volunteers were genotyped, with 70 of them analyzed for sIL-6R levels. Using the PCR/RFLP methods, two important polymorphic sites were selected for genotyping: the 48892A/C (D358A) in exon 9 and the -183G/A in the promoter region. In exon 9, C allele carriers had higher sIL-6R level (P<0.0001) showing that this sequence variation, which corresponds to the proteolytic cleavage site of IL-6Ralpha, strongly influences the serum sIL-6R levels. In the promoter region, G allele carriers had lower sIL-6R levels (P<0.0082) compared with the A allele carriers. This could be attributed to the linkage disequilibrium (D'=0.54, chi2=51.3, P<0.0001) between the -183G/A and the 48892A/C gene polymorphisms.

Protective effect of keishi-bukuryo-gan and its constituent medicinal plants against nitric oxide donor-induced neuronal death in cultured cerebellar granule cells

Keishi-bukuryo-gan (Gui-Zhi-Fu-Ling-Wan) (KBG) is a traditional Chinese/Japanese medical (Kampo) formulation that has been administered to patients with "Oketsu" (blood stagnation) syndrome. In the process of neuronal cell death induced by brain ischemia, excessive generation of nitric oxide (NO) free radicals is implicated in the neurotoxicity. In the present study, we examined the protective effects of KBG and its constituent medicinal plants against NO donors, sodium nitroprusside (SNP) and 2,2'-(hydroxynitrosohydrazino)bis-ethanamine (NOC18)-induced neuronal death in cultured rat cerebellar granule cells (CGCs). MTT assay showed cell viability to be significantly increased by the addition of KBG extract (KBGE) (100 microg/ml), Cinnamomi Cortex extract (CCE) (3, 10 and 30 microg/ml), Paeoniae Radix extract (PRE) (100 microg/ml) and Moutan Cortex extract (MCE) (10 and 30 microg/ml) compared with exposure to SNP (30 microM, 24 h) only. Also, cell viability was significantly increased by the addition of KBGE (100 and 300 microg/ml), CCE (30 and 100 microg/ml), PRE (100 and 300 microg/ml) and MCE (30 and 100 microg/ml) compared with exposure to NOC 18 (100 microM, 48 h) only. Persicae Semen extract and Hoelen extract did not protect against NO donor-induced neuronal death. These results suggest that KBG has protective effect against NO-mediated neuronal death in cultured CGCs and that it is derived from Cinnamomi Cortex, Paeoniae Radix and Moutan Cortex.

Effect of a corticotropin releasing hormone receptor antagonist on colonic sensory and motor function in patients with irritable bowel syndrome

BACKGROUND AND AIMS

Corticotropin releasing hormone (CRH) is a major mediator of the stress response in the brain-gut axis. Irritable bowel syndrome (IBS) is presumed to be a disorder of the brain-gut link associated with an exaggerated response to stress. We hypothesised that peripheral administration of alpha-helical CRH (alphahCRH), a non-selective CRH receptor antagonist, would improve gastrointestinal motility, visceral perception, and negative mood in response to gut stimulation in IBS patients.

METHODS

Ten normal healthy subjects and 10 IBS patients, diagnosed according to the Rome II criteria, were studied. The tone of the descending colon and intraluminal pressure of the sigmoid colon were measured at baseline, during rectal electrical stimulation (ES), and at recovery after administration of saline. Visceral perception after colonic distension or rectal ES was evaluated as threshold values on an ordinate scale. The same measurements were repeated after administration of alphahCRH (10 micro g/kg).

RESULTS

ES induced significantly higher motility indices of the colon in IBS patients compared with controls. This response was significantly suppressed in IBS patients but not in controls after administration of alphahCRH. Administration of alphahCRH induced a significant increase in the barostat bag volume of controls but not in that of IBS patients. alphahCRH significantly reduced the ordinate scale of abdominal pain and anxiety evoked by ES in IBS patients. Plasma adrenocorticotropic hormone and serum cortisol levels were generally not suppressed by alphahCRH.

CONCLUSION

Peripheral administration of alphahCRH improves gastrointestinal motility, visceral perception, and negative mood in response to gut stimulation, without affecting the hypothalamo-pituitary-adrenal axis in IBS patients.

Implications of plasma concentrations of adiponectin in patients with coronary artery disease

OBJECTIVE

To investigate whether concentrations of plasma adiponectin constitute a significant coronary risk factor, with particular focus on the relation between plasma concentrations of adiponectin and the development of acute coronary syndrome (ACS).

SUBJECTS AND METHODS

Plasma concentrations of adiponectin were measured in 123 patients with coronary artery disease (CAD) and in 17 control participants. Patients were divided into three groups according to condition type: acute myocardial infarction (AMI) group (n = 59), unstable angina pectoris (UAP) group (n = 28), and stable angina pectoris (SAP) group (n = 36).

RESULTS

Plasma concentrations of adiponectin correlated negatively with body mass index (r = -0.18, p < 0.05), serum triglyceride (r = -0.25, p < 0.01), and fasting glucose concentrations (r = -0.21, p < 0.05), but correlated positively with age (r = 0.26, p < 0.01), high density lipoprotein cholesterol concentrations (r = 0.35, p < 0.01), and low density lipoprotein particle size (r = 0.37, p < 0.01). Plasma concentrations of adiponectin in patients with ACS, in both the AMI and UAP groups, were significantly lower than those in patients with SAP and in the control group (ACS, 6.5 (3.0) microg/ml; SAP, 11.3 (5.9) micro g/ml; control 12.8 (4.3) microg/ml; p < 0.01). Additionally, plasma concentrations of adiponectin in patients with CAD (7.9 (4.6) microg/ml, p < 0.01) were significantly lower than in the control group. There were, however, no significant differences between patients with SAP and the control group (p = 0.36). Multiple logistic regression analysis showed that smoking, fasting glucose concentration, and low log adiponectin concentration correlated independently with the development of an ACS.

CONCLUSIONS

The findings suggest that measurement of plasma concentrations of adiponectin may be of use for assessing the risk of CAD and may be related to the development of ACS.

Effective bond strength of current adhesive systems on deciduous and permanent dentin

PURPOSE

To evaluate the bond strength of a total-etching, self-priming system (Single Bond) and a self-etching system (Clearfil SE Bond) to deciduous and permanent human dentin.

METHODS AND MATERIALS

Buccal dentin discs were prepared with a diamond disc from permanent first premolars, permanent third molars and deciduous second molars. The flat dentin surfaces were obtained by polishing with wet 600 grit silicon carbide papers. The specimens of each group were further divided into two groups for bonding to either Single Bond or Clearfil SE Bond. After 24 hours, the microshear bond strength testing was executed on a universal testing machine. Statistical analysis was performed at alpha = 0.05.

RESULTS

No significant differences in bond strength were found between materials. However, deciduous dentin demonstrated significantly lower bond strengths than permanent premolar dentin when Single Bond was applied (p < 0.05).

CONCLUSION

The difference in bonding substrate (permanent or deciduous dentin) had a significant effect on bond strength when the total-etching, self-priming system was applied.

Shear bond stability of current adhesive systems to enamel

This study evaluated the micro-shear bond strength of two commercially available resin bonding systems (Single Bond, 3M, USA and SE Bond, Kuraray, Japan) to human enamel. One hundred and twenty enamel sections were prepared from extracted non-carious human molars by cutting with a slowly rotating blade. The enamel surfaces were polished with #280-grift SiC paper under running water. These surfaces were randomly divided into two groups and treated with either Single Bond or Clearfil SE Bond according to manufacturers' instructions. After the bonding procedures, a micro tygon tubing with an internal diameter approximately 0.7 mm and 0.5 mm in height was placed on the enamel surface and Clearfil AP-X resin filled the tube. After the resin was photo-irradiated, the tygon tube was removed. The specimens were further divided into 12 groups according to storage time. All specimens were stored in isotonic sodium chloride solution at 37 degrees C. The bond strength was then measured by means of microshear bond testing at one day, one week, one month, three months, six months and one year. After testing, the fractured surfaces and interfaces were observed using scanning electron microscopy (SEM). The data was analyzed by two-way ANOVA and Fisher's PLSD tests at 95% level of confidence. The result was that both factors (storage time and material) affected bond strength and there was a statistically significant interaction between them. In general, bond strength decreased with time for both materials. The highest bond strengths were achieved at one day with SE Bond and Single Bond. For Single Bond, from one month to one year, the bond strength dramatically decreased. For SE Bond, the decrease in bond strength was gradual. After one-year storage, the bond strength drastically decreased and this value was not significantly different from the results of the one-year storage of Single Bond.

Phase I and pharmacokinetic study of MCC-465, a doxorubicin (DXR) encapsulated in PEG immunoliposome, in patients with metastatic stomach cancer

BACKGROUND

MCC-465 is an immunoliposome-encapsulated doxorubicin (DXR). The liposome is tagged with polyethylene glycol (PEG) and the F(ab')2 fragment of human monoclonal antibody GAH, which positively reacts to >90% of cancerous stomach tissues, but negatively to all normal tissues. In preclinical studies, MCC-465 showed superior cytotoxic activity against several human stomach cancer cells compared with DXR or DXR-incorporated PEG liposomes. The main purpose of this trial was to define the maximum tolerated dose (MTD), dose limiting toxicity (DLT), recommended phase II dose and pharmacokinetics (PK) of MCC-465.

PATIENTS AND METHODS

Patients with metastatic or recurrent stomach cancer were eligible for entry. The initial dose was 6.5 mg/m2. MCC-465 was administered as a 1-h infusion every 3 weeks and the treatment continued for up to six cycles.

RESULTS

Twenty-three patients received a total of 62 cycles at the 6.5-45.5 mg/m2 dose level. DLTs were myelosuppression and appetite loss at the 45.5 mg/m2 dose level. Other toxicities were mild. Neither palmar-plantar erythrodysesthesia nor cardiotoxicity was observed. Acute reactions related to infusion were observed commonly in 16 patients over the entire dose range. While no antitumor response was observed, stable disease (SD) was observed in 10 out of 18 evaluable patients. The pharmacokinetic study showed a similar AUC and Cmax to Doxil.

CONCLUSION

MCC-465 was well tolerated. The recommended dose for a phase II study of MCC-465, for a 3-week schedule, is considered to be 32.5 mg/m2 in an equivalent amount of DXR.

PET neuroreceptor imaging as predictor of severe cerebral ischemic insult

Measurement of the adenosine A1 receptor (A1-R) with positron emission tomography (PET) using a newly developed positron ligand, [1-methyl-11C]8-dicyclopropylmethyl-1-methyl-3-propylxanthine (MPDX). were performed in a cat middle cerebral artery (MCA) occlusion and reperfusion. Eighteen adult cats underwent PET measurement of; 1) cerebral blood flow (CBF). 2) A1-R, 3) central benzodiazepine receptor (BDZ-R) and 4) glucose metabolism with 15O labeled water, MPDX, 11C-flumazenil (FMZ) and 18F-fluorodeoxyglucose (FDG), respectively. The CBF, A1-R, BDZ-R and FDG uptake were serially measured after 60 min occlusion of MCA in this order. MPDX binding and FMZ binding, but not CBF and FDG uptake, were significantly reduced in the groups with severer ischemic insult than in the groups with no or milder insults. Of the two receptor ligands, the reduction rate of the MPDX binding to A1-Rs was larger in a group that caused fatal ischemic insult. The newly developed PET in vivo imaging technique using MPDX was suitable in evaluating the function of adenosine and A1-Rs in relation to cerebral ischemia.

Effects of Keishi-bukuryo-gan on vascular function and hemorheological factors in spontaneously diabetic (WBN/kob) rats

Keishi-bukuryo-gan (Gui-zhi-fu-ling-wan) is a formula used for the improvement of blood circulation. Recently it has often also been used for arteriosclerosis. One of the mechanisms involved is thought to be the improvement of endothelial dysfunction, but the details are still unclear. In this study, the effect of Keishi-bukuryo-gan on vascular function and hemorheological factors in spontaneously diabetic (WBN/kob) rats was studied. Rats were given Keishi-bukuryo-gan in chow for 30 weeks. Body weight, blood glucose, endothelium-dependent/-independent relaxation, vasocontraction by free radical-induced and contractive prostanoids, triglyceride, advanced glycation endproduct, lipid peroxides, serum NO2-/NO3- and blood viscosity were measured. The results indicated that Keishi-bukuryo-gan caused a decrease in endothelium-dependent relaxation by acetylcholine to become significantly increased, and vasocontraction induced by free radicals and contractive prostanoids was significantly decreased. Furthermore, serum NO2-/NO3- and blood viscosity were significantly decreased. From these results, it was supposed that Keishi-bukuryo-gan exerted a protective effect on the endothelium. The WBN/kob rat is a useful study model for the complications of human diabetes, and Keishi-bukuryo-gan showed a protective effect against vascular injury in the susceptible rat.

The effects of a herbal medicine (Mao-to) in patients with chronic hepatitis C after injection of IFN-beta

We found that a herbal medicine (Mao-to) relieves the side effects of interferon (IFN)-beta and the combination therapy improves the biochemical response rate. However, the exact mechanism by which Mao-to is effective remains to be established. We conducted a controlled trial to clarify the effects of Mao-to. The study was carried out in 18 patients with chronic hepatitis C, and we examined subjective symptoms, body temperature and cytokines such as interleukin (IL)-beta, IL-1receptor antagonist (ra), IL-6 and TNF-alpha. Each patient received 6 million units of IFN-beta intravenously. Mao-to was given orally just before, just after, and 1 hour after IFN administration. The control study was carried out 6 months after the combination therapy of Mao-to and IFN-beta. The scores for general malaise, arthralgia and discomfort were significantly lower in the combination group than in control group. Body temperature did not significantly differ between the two groups. Plasma IL-6 level and IL-1ra were significantly elevated in the combination group compared to control (P = 0.0057 and 0.0003, respectively). Mao-to did not affect plasma concentrations of IL-1beta and TNF-alpha. We considered the increment of IL-1ra caused by Mao-to is to be one of the key factors involved in reducing the flu-like symptoms accompanying IFN-beta and improving the biochemical response rate.

Growth inhibition through activation of peroxisome proliferator-activated receptor gamma in human oesophageal squamous cell carcinoma

Peroxisome proliferator-activated receptor gamma (PPARgamma) heterodimerises with retinoid X receptor alpha (RXRalpha) and is thought to be a novel therapeutic target for human malignancies. We evaluated the ability of troglitazone (TRO) alone or in combination with 9-cis retinoic acid (9CRA), ligands of PPARgamma and RXRalpha, respectively, to inhibit the growth of oesophageal squamous cell carcinoma (OSCC). All 10 tested OSCC cell lines of a KYSE series expressed PPARgamma and RXRalpha at both the mRNA and protein levels. In four tested cell lines, TRO inhibited growth, and a synergistic effect was observed with simultaneous 9CRA application. In KYSE 270 cells, a luciferase reporter assay showed that the simultaneous application of TRO and 9CRA to the cells increased the relative luciferase activity approximately 20-fold compared with the controls without TRO or 9CRA application. In this cell line, flow cytometry demonstrated that combined treatment with TRO and 9CRA greatly increased the sub-G1 phase, and Hoechst 33342/propidium iodide (PI) staining showed that apoptotic cell death was mainly induced through ligand treatment. In addition, implanted tumours in nude mice showed significant inhibition of tumour growth when treated with TRO. These results suggest that the PPARgamma/RXRalpha heterodimer may be a new therapeutic target for OSCC.

Validity of intraoperative pathological diagnosis of paratracheal lymph node as a strategy for selection of patients for cervical lymph node dissection during esophagectomy

The aim of this paper is to examine whether intraoperative examination of paratracheal nodes can indicate cervical node dissection and whether this approach is valid. From 1988 to 1997, 76 patients with thoracic esophageal squamous cell carcinoma received esophagectomies with and without cervical lymph node (LN) dissection based on the results of intraoperative pathological diagnosis from selective checking of paratracheal LN. We retrospectively examined the outcomes for the patients and the micro metastasis in the dissected lymph node using cytokeratin staining. Three of the seven patients with cervical LN dissection were detected as having cervical LN metastasis by postoperative hematoxylin-eosin or cytokeratin staining. Five (7%) of the 69 patients without cervical LN dissection had cervical LN recurrence after the operation. Four of the seven patients who were diagnosed as having metastasis or micro metastasis in paratracheal LN by postoperative examination had cervical LN recurrence after the operation. In conclusion, the esophagectomy with and without cervical LN dissection for thoracic esophageal squamous cell carcinoma based on the results of intraoperative pathological diagnosis from selective checking of paratracheal LN was not fully acceptable. The reliability of intraoperative pathological diagnosis of selective checking may improve by increasing the number of checked LN and the detection of micro metastasis.

Plasma concentrations of 5-fluorouracil and F-beta-alanine following oral administration of S-1, a dihydropyrimidine dehydrogenase inhibitory fluoropyrimidine, as compared with protracted venous infusion of 5-fluorouracil

The pharmacokinetics and pharmacodynamics of oral S-1, a dihydropyrimidine dehydrogenase (DPD) inhibitory fluoropyrimidine, were compared with those of protracted venous infusion (PVI) of 5-fluorouracil (5-FU). In all, 10 patients with gastric cancer received PVI of 5-FU at a dose of 250 mg m(-2) day(-1) for 5 days. After a washout period of 9 days, the patients received two divided doses daily for 28 days. S-1 was administered orally at about 0900 and 1900 hours. The daily dose of S-1 in terms of tegafur was 80 mg day(-1) in patients with a body surface area (BSA) of <1.25 m(2), 100 mg day(-1) in those with a BSA of >or=1.25 m(2) to <1.5 m(2), and 120 mg day(-1) in those with a BSA of >or=1.5 m(2). Plasma concentrations of 5-FU and F-beta-alanine (FBAL) were measured for pharmacokinetic analysis, and the plasma uracil concentration was monitored as a surrogate marker of DPD inhibition (pharmacodynamic analysis) in the same patients on days 1-5 of PVI of 5-FU and on days 1-5 of oral S-1. The area under the curve (AUC(0-10 h)) of 5-FU on day 5 was 728+/-113 ng h ml(-1) for PVI of 5-FU and 1364+/-374 ng h ml(-1) for S-1. The median 5-FU PVI : S-1 ratio of the AUC(0-10 h) of 5-FU was 1.9. The AUC(0-10 h) of FBAL on day 5 of PVI of 5-FU was 9465+/-3225 ng h ml(-1), AUC(0-10 h), as compared with 1725+/-605 ng h ml(-1) on day 5 of S-1 treatment. The AUC(0-10 h) of uracil on day 5 was 252+/-60 ng h ml(-1) with PVI of 5-FU and 12 582+/-3060 ng h ml(-1) with S-1. The AUC(0-10 h) of FBAL was markedly lower and plasma uracil concentrations were significantly higher for S-1 than for PVI of 5-FU, clearly demonstrating the effect of DPD inhibition.

Single-nucleotide polymorphism in the CD14 promoter and periodontal disease expression in a Japanese population

It has been reported that there is a relationship between a single-nucleotide polymorphism (SNP) in the promoter region of the CD14 gene at position -159 (C-->T) and infectious diseases. The aim of the present study was to test the hypthesis that expression of this SNP correlates with periodontal disease in a Japanese population. The CD14 genotype was determined in 163 subjects with periodontitis and in 104 age- and gender-matched control subjects without periodontitis. The genotype distribution and allele frequency within the periodontitis patients were not significantly different from those of control subjects. There was, however, a significant difference in the genotype distribution between young patients (< 35 yrs) and older patients (>/==" BORDER="0"> 35 yrs). These findings suggest that CD14 -159C/T polymorphism is not related to the development of periodontitis in a Japanese population, but that, within the periodontitis subjects, expression of the SNP may be related to early disease activity.

[Off-pump coronary artery bypass grafting; its impact on renal function]

PURPOSE

We evaluated the impact of off-pump coronary artery bypass grafting (off-pump CABG: OPCAB) on the perioperative renal function.

METHODS

Isolated CABG was performed on 359 patients during the period from January 1999 to September 2002. Nine patients on dialysis were excluded from this study and 350 patients were divided into 2 groups: OPCAB Group (n = 214) and on-pump Group (n = 136). Perioperative serum CRE levels of the 2 groups were compared.

RESULTS

The ratio of patients with renal impairment (CRE > 1.5 mg/dl) in the OPCAB Group was 8%, which did not differ statistically from that of the on-pump Group (4%). Patients who had renal impairment postoperatively accounted for 20% of the OPCAB Group, which did not differ from that of the on-pump Group (18%). The postoperative CRE/preoperative CRE ratio was lower in the OPCAB Group (1.28) than that of the on-pump Group (1.44).

CONCLUSION

The renal function was preserved in the OPCAB Group compared to the on-pump Group.

Genetic susceptibility to thymic lymphomas and K-ras gene mutation in mice after exposure to X-rays and N-ethyl-N-nitrosourea

PURPOSE

Ras activation is one of the major mechanisms for the development of murine thymic lymphomas by radiation and chemical carcinogens. To gain insight into the relationship between genetic susceptibility and ras gene mutation, the frequency and spectrum of ras gene mutation was examined in thymic lymphomas from susceptible and resistant mice.

MATERIALS AND METHODS

K- and N-ras mutations in thymic lymphomas that arose in X-ray-irradiated and N-ethyl-N-nitrosourea (ENU)-treated mice of susceptible C57BL/6, rather resistant C3H and their hybrid B6C3F1 were analysed by polymerase chain reaction-single-strand conformation polymorphism and subsequent DNA sequencing.

RESULTS

C57BL/6 exhibited a higher incidence of thymic lymphomas after exposure to X-rays and ENU than C3H, with B6C3F1 being intermediate. K-ras gene mutations occurred frequently in the pathogenesis of ENU-induced thymic lymphomas in susceptible C57BL/6 as opposed to resistant C3H. The ras mutations were more frequent in ENU-induced thymic lymphomas than X-ray-induced thymic lymphomas, and with the latter, there was no clear evidence for strain differences, suggesting that the genetic susceptibility to X-rays was independent of ras activation. The mutations of K-ras in thymic lymphomas from C57BL/6 were predominantly GGT to GAT in codon 12, whereas this mutation type was never found in those from C3H. No strain difference was observed in the nucleotide sequence or expression levels of O(6)-alkylguanine alkyltransferase, indicating that this enzyme did not account for the genetic susceptibility to ras activation.

CONCLUSIONS

The results indicate that there is a clear strain and carcinogen dependency of K-ras mutation and that the frequency of ras mutation might determine the genetic susceptibility to ENU-induced lymphomagenesis, whereas pathways independent of ras activation might determine the susceptibility to X-ray-induced lymphomagenesis.

Recycling compartments and the internal vesicles of multivesicular bodies harbor most of the cholesterol found in the endocytic pathway

We employed our recently developed immuno-electron microscopic method (W. Möbius, Y. Ohno-Iwashita, E. G. van Donselaar, V. M. Oorschot, Y. Shimada, T. Fujimoto, H. F. Heijnen, H. J. Geuze and J. W. Slot, J Histochem Cytochem 2002; 50: 43-55) to analyze the distribution of cholesterol in the endocytic pathway of human B lymphocytes. We could distinguish 6 categories of endocytic compartments on the basis of morphology, BSA gold uptake kinetics and organelle marker analysis. Of all cholesterol detected in the endocytic pathway, we found 20% in the recycling tubulo-vesicles and 63% present in two types of multivesicular bodies. In the multivesicular bodies, most of the cholesterol was contained in the internal membrane vesicles, the precursors of exosomes secreted by B cells. Cholesterol was almost absent from lysosomes, that contained the bulk of the lipid bis(monoacylglycero)phosphate, also termed lysobisphosphatidic acid. Thus, cholesterol displays a highly differential distribution in the various membrane domains of the endocytic pathway.

Ixodid tick species recovered from domestic dogs in Japan

The species of ixodid ticks (Acari: Ixodidae) recovered from domestic dogs in Japan between September to November 2000 and April to June 2001 were identified. A total of 4122 ticks, including 1624 larvae, 1200 nymphs, 1016 females and 282 males were removed from 1221 dogs during these periods. Haemaphysalis longicornis (Neumann) was the most frequently found (40.3% of dogs), followed by H. flava (Neumann) (16.1% of dogs), Rhipicephalus sanguineus (Latreille) (4.8% of dogs) and Ixodes ovatus (Neumann) (4.1% of dogs). Small numbers of H. hystricis (Supino), H. campanulata (Warburton), H. japonica (Warburton), H. ias (Nakamura and Yajima), I. persulcatus (Schulze), I. nipponensis (Kitaoka and Saito) and Amblyomma testudinarium (Koch) were also recovered. In the spring sample, a total of 1408 ticks (78 larvae, 411 nymphs, 792 adult females and 127 adult males) were recovered from 570 dogs. The autumn sample included a larger proportion of larval stage and fewer adult ticks (1546 larvae, 789 nymphs, 224 adult females and 155 adult males). Haemaphysalis longicornis, H. flava and I. ovatus showed a wide geographical distribution from northern to southern Japan, whereas R. sanguineus were mainly distributed in the subtropical Okinawa prefecture with a few exceptions. Dogs in rural areas more frequently carried H. longicornis, H. flava and I. ovatus than dogs in urban or suburban areas, whereas R. sanguineus was more associated with the dogs in urban/suburban areas. Exposure to a garden was significantly associated with R. sanguineus and exposure to woodland was significantly associated with H. flava and I. ovatus. This is the first systematic survey of canine ticks in Japan.

Measurement of plasma procyanidin B-2 and procyanidin B-3 levels after oral administration in rat

Using a high-performance liquid chromatographic method and mass spectrometry analysis, we successfully measured the absorption of orally administered procyanidin B-2 and procyanidin B-3 isolated from Cinnamonomi cortex (the bark of Cinnamomum cassia Blume) in the rat plasma. This method used a TSK- GEL ODS-80TS column, two solvents (A: 0.01% acetic acid; B: methanol with 0.01% acetic acid) in a linear gradient at a flow-rate of 1.0 ml/min, and fluorescence detection at excitation and emission wavelengths of 220 and 327 nm.

Amino acid mutagenesis of the ligand binding site and the dimer interface of the metabotropic glutamate receptor 1. Identification of crucial residues for setting the activated state

Previously, we determined the crystal structures of the dimeric ligand binding region of the metabotropic glutamate receptor subtype 1. Each protomer binds l-glutamate within the crevice between the LB1 and LB2 domains. We proposed that the two different conformations of the dimer interface between the two LB1 domains define the activated and resting states of the receptor protein. In this study, the residues in the ligand-binding site and the dimer interface were mutated, and the effects were analyzed in the full-length and truncated soluble receptor forms. The variations in the ligand binding activities of the purified truncated receptors are comparable with those of the full-length form. The mutated full-length receptors were also analyzed by inositol phosphate production and Ca(2+) response. The magnitude of the ligand binding capacities and the amplitude of the intracellular signaling were almost correlated. Alanine substitutions of four residues, Thr(188), Asp(208), Tyr(236), and Asp(318), which interact with the alpha-amino group of glutamate in the crystal, abolished their responses both to glutamate and quisqualate. The mutations of the Tyr(74), Arg(78), and Gly(293) residues, which interact with the gamma-carboxyl group of glutamate, lost their responsiveness to glutamate but not to quisqualate. Furthermore, a mutant receptor containing alanine instead of isoleucine at position 120 located within an alpha helix constituting the dimer interface showed no intracellular response to ligand stimulation. The results demonstrate the crucial role of the dimer interface in receptor activation.