Fundamental study of osteoclast chemotaxis toward chemoattractants expressed in periodontitis

BACKGROUND AND OBJECTIVE

Periodontitis is a chronic inflammatory disease that leads to bone resorption by osteoclasts (OCs). Several factors contribute to the differentiation of OCs from hematopoietic precursors. Cellular chemotactic factors are expressed in periodontitis tissue, but the effects of these chemoattractants on OCs are not well understood. Here we examined the effects of chemoattractants produced in inflamed periodontal tissue on OC chemotaxis.

MATERIAL AND METHODS

Rat bone-marrow OCs were cultured in OC culture medium for 3 or 6 d. Using EZ-TAXIScan™, the chemotactic response of these OCs to several chemoattractants [monocyte chemotactic protein-1; macrophage inflammatory protein 1α; regulated on activation, normal T-cell expressed and secreted; stromal cell-derived factor-1α; and complement activation product 5a (C5a)] was measured. In addition, we measured the effect of C5a-specific inhibitors on chemotactic responses toward C5a. The recorded chemotactic responses were quantitatively analysed using ImageJ software.

RESULTS

Chemoattractants associated with periodontal disease significantly increased the chemotactic activity of differentiated rat OCs in a concentration-dependent manner, with C5a inducing the highest chemotactic activity of OCs cultured for 3 or 6 d. The C5a-specific inhibitor significantly inhibited chemotaxis toward C5a in a concentration-dependent manner.

CONCLUSION

We suggest that C5a plays an important role in pathologic bone resorption in periodontal disease by stimulating the chemotaxis of OCs. Therefore, C5a is a potential target for the treatment of periodontal disease.

Abstract P6-04-17: The androgen metabolite-dependent growth in hormone receptor positive breast cancer as a novel aromatase inhibitor-resistance mechanism

Introduction: Aromatase inhibitors (AIs) have been reported to exert their anti-proliferative effects not only by reducing the production of estrogens but also by unmasking the inhibitory effect of androgens such as testosterone (TS) or dihydrotestosterone (DHT) in postmenopausal women with hormone receptor-positive breast cancer. The behavior of androgens in AI-resistance mechanisms is not sufficiently understood. 5α-androstane-3β,17β-diol (3β-diol) generated from DHT by 3β-hydroxysteroid dehydrogenase type 1 (3β-HSD type 1: HSD3B1) has androgenic activity and substantial estrogenic activity, representing a potential mechanism of AI resistance.

Methods: To investigate these issues, ERE-GFP-transfected MCF-7-E10 cells were cultured for 3 months under steroid-depleted, TS-supplemented conditions which is the similar as the AI treatment. Among the surviving cells, two stable variants that show ER activity depending on androgen metabolites were selected as AD-EDR (androgen metabolite-dependent and estrogen depletion-resistant) by monitoring GFP expression. Using these cell lines, we investigated the process of adaptation to androgen-abundant conditions and the role of androgens in AI-resistance mechanisms.

Results: AD-EDR cell lines showed increased growth and induction of estrogen-responsive genes rather than androgen-responsive genes by androgens or 3β-diol. Further analysis revealed increased expressions of HSD3B1 and reduced expression of androgen receptor (AR) in these cell lines. In parental MCF-7-E10 cells, ectopic expression of HSD3B1 or inhibition of AR resulted in adaptation to estrogen-deprived and androgen-abundant conditions. In coculture with stromal cells replicating the local estrogen production from androgen, AD-EDR cell lines showed AI resistance compared with parental MCF-7-E10 cells. Immunohistochemistry and real-time PCR analyses on 9 pairs of primary and recurrent tissue samples from AI-resistant breast cancer revealed the decrease of AR protein expression in all cases and increase of HSD3B1 mRNA expression in 5.

Conclusion: In the present study, we successfully cloned two stable variants that show ER activity depending on androgen metabolites. Investigation of these cell lines suggested that the increased function of 3β-HSD type 1 and reduced function of AR contribute to AI resistance by enhancing the androgen metabolite-dependent growth and reducing the inhibitory effect of androgens. Our data of clinical samples suggest that this mechanism also acts as an AI-resistance in clinical breast cancer in some cases.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-04-17.

Outcome measurement of extensive implementation of antimicrobial stewardship in patients receiving intravenous antibiotics in a Japanese university hospital

BACKGROUND

Antimicrobial stewardship has not always prevailed in a wide variety of medical institutions in Japan.

METHODS

The infection control team was involved in the review of individual use of antibiotics in all inpatients (6348 and 6507 patients/year during the first and second annual interventions, respectively) receiving intravenous antibiotics, according to the published guidelines, consultation with physicians before prescription of antimicrobial agents and organisation of education programme on infection control for all medical staff. The outcomes of extensive implementation of antimicrobial stewardship were evaluated from the standpoint of antimicrobial use density, treatment duration, duration of hospital stay, occurrence of antimicrobial-resistant bacteria and medical expenses.

RESULTS

Prolonged use of antibiotics over 2 weeks was significantly reduced after active implementation of antimicrobial stewardship (2.9% vs. 5.2%, p < 0.001). Significant reduction in the antimicrobial consumption was observed in the second-generation cephalosporins (p = 0.03), carbapenems (p = 0.003), aminoglycosides (p < 0.001), leading to a reduction in the cost of antibiotics by 11.7%. The appearance of methicillin-resistant Staphylococcus aureus and the proportion of Serratia marcescens to Gram-negative bacteria decreased significantly from 47.6% to 39.5% (p = 0.026) and from 3.7% to 2.0% (p = 0.026), respectively. Moreover, the mean hospital stay was shortened by 2.9 days after active implementation of antimicrobial stewardship.

CONCLUSION

Extensive implementation of antimicrobial stewardship led to a decrease in the inappropriate use of antibiotics, saving in medical expenses, reduction in the development of antimicrobial resistance and shortening of hospital stay.

Benefits and risks associated with the R100 high frequency oscillatory ventilator for patients with severe hypoxaemic respiratory failure

High frequency oscillatory ventilation has been shown to improve oxygenation of patients with severe respiratory failure. This prospective study examined the potential benefits and risks of the latest generation high frequency oscillatory ventilator (R100, Metran, Saitama, Japan), initiated when the target oxygenation could not be achieved by conventional mechanical ventilation in adult patients with severe hypoxaemic respiratory failure. Thirty-six patients with severe respiratory failure treated with the R100 high frequency oscillatory ventilator were considered. Pneumonia and exacerbation of interstitial pneumonia were the main causes of respiratory failure. The median time on conventional mechanical ventilation or airway pressure release ventilation prior to high frequency oscillatory ventilation was 9.3 hours (interquartile range 4.8 to 25). PaO2/FiO2 at 24 hours after initiation of high frequency oscillatory ventilation was significantly better than the PaO2/FiO2 at baseline (151.2 +/- 61.2 vs. 99.5 +/- 50.0, P = 0.0001). Refractory hypoxaemia within 24 hours was associated with a high risk of mortality (P = 0.0092) and 23 patients (64%), including 11 patients with exacerbation of interstitial pneumonia, died by 30 days. Of the 36 patients included in the study (including one who had developed pneumothorax before high frequency oscillatory ventilation), 12 (33%) developed barotrauma during the course of their intensive care unit stay. In the multivariate analysis, only exacerbation of interstitial pneumonia was a significant risk factor for barotrauma. In summary, the latest generation high frequency oscillatory ventilator could improve oxygenation in adult patients with life-threatening hypoxaemic respiratory failure but the incidence of barotrauma was substantial.

The spectrum of associated brain lesions in cerebral sinovenous thrombosis: relation to gestational age and outcome

OBJECTIVE

To describe different patterns of associated brain lesions in preterm and full-term infants with cerebral sinovenous thrombosis (CSVT) and to assess whether these different patterns are related to gestational age at onset.

DESIGN

Magnetic resonance scans of all neonates (six preterm, 24 full term) with suspected CSVT, collected over a 7-year period in two neonatal intensive care units, were evaluated to assess patterns of associated brain lesions. Comparisons between the two gestational age groups were made.

RESULTS

CSVT was confirmed on magnetic resonance venography in 26 of 30 neonates (six preterm, 20≥36 weeks' gestational age). The straight (85%) and superior sagittal (65%) sinus were most often affected. Several sinuses were involved in 81% of infants. White matter damage affecting the entire periventricular white matter was seen in five of six preterm infants. Intraventricular haemorrhage (IVH) was common in both groups (4/6 preterm, 16/20 full term). Frontal punctate white matter lesions with restricted diffusion (15/20) and thalamic haemorrhage associated with IVH (11/20) were the most frequent lesions in full-term infants. Focal arterial infarction was present in four of 20 full-term infants. Six infants died in the neonatal period (four preterm, two full term). Follow-up MRIs at 3 months in all survivors showed evolution of the lesions with frontal atrophy in 13 of 20 (12 full term) and delayed myelination in seven of 20 (six full term).

CONCLUSIONS

Preterm and full-term neonates show different patterns of associated brain lesions. Extensive white matter damage is the predominant pattern of injury in the preterm infant, while an IVH associated with a thalamic haemorrhage and punctate white matter lesions are more common in the full-term infant.

The Analysis of Drug Release from Diluted Water/oil/water Emulsions by a Model of the Rupture of Oil Membrane

The release behaviour of theophylline encapsulated in the inner aqueous phase of a water/oil/water emulsion was investigated by two methods. A cellulose tube containing a sample of the emulsion was placed in a rotary basket and was stirred in a dissolution medium (Method A), or the w/o/w emulsion was dispersed in a dissolution medium and the system was stirred by a paddle, allowing the drug to permeate into a cellulose tube placed in the dispersing medium (Method B).

In Method A, the drug release rate from the emulsion decreased with increase in the concentration of sodium chloride co-formulated with the drug in the inner aqueous phase. The drug release rate in the dissolution test medium No. 1 or No. 2 of the JP XII was greater than that in purified water and was increased with the ionic strength of the dissolution medium. The drug was released more rapidly in Method B than in Method A, because the emulsion was destroyed more easily using the former method. As this destruction of emulsion structure occurred immediately after dilution with dissolution medium, the influence of the dissolution medium on the release profile could not be detected using Method B.

The experimental data of drug release were satisfactorily explained by the destruction model of the oil membranes of the water/oil/water emulsions.

Influence of leukotriene pathway polymorphisms on clinical responses to montelukast in Japanese patients with asthma

WHAT IS KNOWN AND OBJECTIVE

Montelukast, a cysteinyl leukotriene receptor 1 antagonist, is safe and efficacious in patients with asthma. The mechanisms underlying the significant interpatient variability in response to montelukast are not clear but are believed to be, in part, because of genetic variability.

METHODS

To examine the associations between polymorphisms in candidate genes in the leukotriene pathway and outcomes in patients with asthma on montelukast for 4-8 weeks, we evaluated the changes in peak expiratory flow (PEF), forced expiratory volume in 1 s (FEV(1·0) ) and patients' subjective symptom before and after montelukast treatment. DNA was collected from 252 Japanese participants.

RESULTS AND DISCUSSION

Two single-nucleotide polymorphisms (SNPs) in the ALOX5 (rs2115819) and LTA4H (rs2660845) genes were successfully typed. There was no difference between members of the general population (n = 200) and patients (n = 52) in each genotype frequency. Significant associations were found between SNP genotypes in the LTA4H gene and changes in PEF and FEV(1·0) . The PEF and FEV(1·0) responses to montelukast in the A/A genotypes (n = 4) for the LTA4H SNP were significantly higher than those in the G allele carriers (A/G+G/G) (n = 17).

WHAT IS NEW AND CONCLUSION

Despite the small sample size, our results suggest that genetic variation in leukotriene pathway candidate genes contributes to variability in clinical responses to montelukast in Japanese patients with asthma.

Abnormal basiocciput development in CHARGE syndrome

BACKGROUND AND PURPOSE

The causative gene of the common congenital malformation referred to as CHARGE syndrome is CHD7. Affected individuals often undergo head and neck imaging to assess abnormalities of the olfactory structures, hypothalamus-pituitary axis, and inner ear. We encountered a few children with severe hypoplasia of the basiocciput during a radiologic assessment of patients with CHARGE syndrome. To our knowledge, this anomaly has not been reported. Our purpose was to evaluate the incidence and severity of this anomaly in this syndrome.

MATERIALS AND METHODS

Sagittal MR images of 8 patients with CHARGE syndrome were retrospectively reviewed by 2 radiologists who consensually evaluated the status of the basiocciput of the patients with CHARGE syndrome, as either normal or hypoplastic; and associated anomalies, which include basilar invagination, Chiari type I malformation, and syringomyelia, as either present or absent. The length between the basion (Ba) and the endo-sphenobasion (Es) and between the basion and the exo-sphenobasion (Xs) was measured on midsagittal MR images of the 8 patients and 70 age-matched controls. We searched for trends related to age in the length of Ba-Es and Ba-Xs of the control children by using a matched t test.

RESULTS

Basioccipital hypoplasia was identified in 7 of the 8 patients with CHARGE syndrome and was severe in 6. Of those, 5 had associated basilar invagination and 1 had Chiari type I malformation with syringomyelia.

CONCLUSIONS

Basioccipital hypoplasia and basilar invagination are prevalent in patients with CHARGE syndrome.

Advanced pancreatic cancer: the use of the apparent diffusion coefficient to predict response to chemotherapy

The purpose of this study was to determine if the apparent diffusion coefficient (ADC) on diffusion-weighted MRI could predict the response of patients with advanced pancreatic cancer to chemotherapy. Diffusion-weighted MRI was performed in 63 consecutive patients with advanced pancreatic cancer who were subsequently treated with chemotherapy. The ADC values of the primary tumour with a middle b-value (400 s mm(-2)) and a high b-value (1000 s mm(-2)) were determined; cystic or necrotic components were avoided. The patients were classified into two groups: (i) those with progressive disease and (ii) those who were stable 3 months and 6 months after initial treatment. The groups were compared with respect to the ADC and clinical factors, including gender, age, Union International Contre le Cancer (UICC ) stage, initial tumour size and chemotherapy agents used. Local tumour progression rates were evaluated using the Kaplan-Meier method. The middle b-value ADC of the pancreatic cancers ranged from 0.93-2.42 x10(-3) mm(2) s(-1) (mean, 1.50 x10(-3) mm(2) s(-1)), and the high b-value ADC ranged from 0.72-1.88 x10(-3) mm(2) s(-1) (mean, 1.20 x10(-3) mm(2) s(-1)). The high b-value ADC was significantly different between the progressive and stable groups at 3 months' and 6 months' follow-up (p = 0.03 and p = 0.04, respectively). The rate of tumour progression was significantly higher in those with a lower high b-value ADC than in those with a higher b-value ADC (median progression time, 140 days vs 182 days; p = 0.01). In conclusion, a lower high b-value ADC in patients with advanced pancreatic cancer may be predictive of early progression in chemotherapy-treated patients.

Susceptibility-weighted imaging findings of cortical laminar necrosis in pediatric patients

BACKGROUND AND PURPOSE

MR susceptibility-weighted imaging (SWI) is a highly sensitive technique for detection of hemorrhage, but its utility in the evaluation of children with laminar necrosis is not yet known. We assessed whether cortical laminar necrosis in pediatric patients contains hemorrhage on SWI.

MATERIALS AND METHODS

"Cortical laminar necrosis" was defined as a hyperintense cortical lesion on T1-weighted imaging in the subacute or chronic phase of brain damage in some foci involving the cerebral cortex and white matter such as hypoxic-ischemic incidents and encephalopathy. Medical records, CT, and MR images were retrospectively analyzed. Fifteen patients (7 boys, 8 girls; age range, 0-13 years) were included. The areas of signal-intensity loss on SWI that were considered to be hemorrhage were correlated with the laminar necrosis. CT was assessed to correlate with the presence of calcification at the location of the signal-intensity loss on SWI. To assess appearance or signal-intensity changes of hemorrhage in the laminar necrosis, follow-up SWI was performed.

RESULTS

The causes of laminar necrosis included infarction in 4 patients, ischemic changes from Moyamoya disease in 2, meningoencephalitis in 2, hypoxic-ischemic encephalopathy in 2, shaken baby syndrome in 1, encephalopathy from severe infection in 1, status epilepticus in 1, citrullinemia in 1, and brain injury with posterior reversible encephalopathy syndrome in 1. T1-weighted imaging showed focal laminar necrosis in 8, multifocal laminar necrosis in 2, and diffuse laminar necrosis in 5. SWI findings correlated with laminar necrosis included the following: no hemorrhage in 13 patients (80.0%), dotted hemorrhage in 2 (13.3%), and laminar hemorrhage in 1 (6.7%). Follow-up SWI performed in 6 patients showed no additional hemorrhage.

CONCLUSION

Most areas of cortical laminar necrosis in pediatric patients showed no hemorrhage on SWI.

Evaluation of the role of breast cancer resistance protein (BCRP/ABCG2) and multidrug resistance-associated protein 4 (MRP4/ABCC4) in the urinary excretion of sulfate and glucuronide metabolites of edaravone (MCI-186; 3-methyl-1-phenyl-2-pyrazolin-5-one)

Edaravone (MCI-186; 3-methyl-1-phenyl-2-pyrazolin-5-one), a free radical scavenger, is used for the treatment of acute cerebral infarction. Edaravone is mainly excreted into the urine after conjugation to glucuronide or sulfate. Previous studies have demonstrated that edaravone sulfate is a good substrate of human organic anion transporter (OAT) 1 (SLC22A6) and human OAT3 (SLC22A8). In this study, we examined the involvement of breast cancer resistance protein [BCRP (ABCG2)] and [multidrug resistance-associated protein 4 MRP4 (ABCC4)] in the luminal efflux in the kidney. Increased ATP-dependent uptake of edaravone sulfate but not edaravone glucuronide was observed in BCRP-expressing membrane vesicles compared with control vesicles (Km = 16.5 microM). In contrast, edaravone glucuronide, but not edaravone sulfate, exhibited greater ATP-dependent uptake in MRP4-expressing membrane vesicles than that in control vesicles (Km = 9.85 microM). Unlike taurocholate uptake, S-methylglutathione had no effect on the ATP-dependent uptake of edaravone glucuronide by MRP4. The functional importance of BCRP and MRP4 in the urinary excretion of edaravone sulfate and edaravone glucuronide, respectively, was investigated using Bcrp and Mrp4 knockout mice. The renal clearance with respect to the kidney concentration of edaravone sulfate was reduced significantly but not abolished in Bcrp knockout mice compared with wild-type mice (3.62 versus 4.85 ml/min/kg b.wt.). The renal clearance of edaravone glucuronide was lower in Mrp4 knockout mice than wild-type mice (2.01 versus 5.06 ml/min/kg BW). Our results suggest that Bcrp and Mrp4 are partly involved in the luminal efflux of edaravone sulfate and edaravone glucuronide, respectively.

The correlation of perfusion-weighted MRI with VEGF in resected pancreatic cancer

15092

Background: Perfusion-weighted magnetic resonance imaging (MRI) can detect angiogenesis in brain malignant tumors, and as angiogenesis increases in various carcinomas the prognosis becomes worse. We evaluated the usefulness of perfusion-weighted MRI as a prognostic predictor in pancreatic cancer patients in ASCO 2005. This time, we examined the correlation of perfusion-weighted MRI with vascular endothelial growth factor (VEGF) and microvessel density (MVD) immunohistochemically in resected pancreatic cancer patients. Methods: Perfusion-weighted MRI was performed on 14 consecutive resected pancreatic cancer cases. Imaging acquisition was continually repeated with echo-planar sequence every 2 sec for 2 min with bolus injection of gadolinium. We made the time intensity curve of perfusion-weighted images and calculated the signal ratio (SR). We investigated the expressions of VEGF and CD34 (for calculating MVD) immunohistochemically. MVD was assessed per 200x field. We compared SR with VEGF expression and MVD. The correlations were evaluated with t-test. Results: All cases showed transient decreases in tumor signal intensity (SR range: 18.2–66.0%) in perfusion-weighted MRI. The expressions of VEGF were divided into two groups (high and low expression). MVD ranged from 6 to 34 and was divided into two groups at the median value. The correlation of SR in perfusion-weighted MRI with VEGF expression was significant (p=0.002). High SR correlated with high VEGF expression. The correlation of SR in perfusion-weighted MRI with MVD was not significant. Conclusions: Perfusion- weighted MRI correlated with VEGF expression in pancreatic cancer.

No significant financial relationships to disclose.

Human Organic Anion Transporters 1 (hOAT1/SLC22A6) and 3 (hOAT3/SLC22A8) Transport Edaravone (MCI-186; 3-methyl-1-phenyl-2-pyrazolin-5-one) and Its Sulfate Conjugate

3-Methyl-1-phenyl-2-pyrazolin-5-one (MCI-186; edaravone), a novel free radical scavenger, is used for the treatment of acute cerebral infarction. After marketing, a few cases of acute renal failure were reported in patients following treatment with this drug. Because edaravone is mainly excreted into the urine following conjugation to glucuronide or sulfate, the renal excretion mechanisms of edaravone should help provide important information when considering the clinical cases. We examined the transport of edaravone and its sulfate and glucuronide conjugates via human organic anion transporter 1 (hOAT1) and 3 (hOAT3), expressed on the basolateral membranes of proximal tubules. The hOAT1- and hOAT3-transfected human embryonic kidney (HEK)-293 cells exhibited a markedly higher uptake of edaravone sulfate and a slightly higher uptake of edaravone than vector-transfected cells. The K(m) values of edaravone sulfate uptake by hOAT1 and hOAT3 were 11 and 15 microM, respectively. Estimation of the relative contribution of hOAT1 and hOAT3 using reference compounds suggested that hOAT1 and hOAT3 might contribute to the renal uptake of edaravone sulfate to the same extent. However, edaravone and its sulfate showed no cytotoxicity toward both hOAT1-HEK and control cells, suggesting that higher uptake in hOAT1-HEK did not associate with cytotoxicity of these compounds. In conclusion, our results suggest that both hOAT1 and hOAT3 are responsible for the basolateral uptake of edaravone sulfate in the kidney.

Aldose reductase gene is associated with diabetic macroangiopathy in Japanese Type 2 diabetic patients

AIMS

The aldose reductase (AR) gene, a rate-limiting enzyme of the polyol pathway, has been investigated as a candidate gene in determining susceptibility to diabetic microangiopathy. However, the association of the AR gene with diabetic macroangiopathy has not been investigated. Therefore, the present study was conducted to determine whether genetic variations of AR may determine susceptibility to diabetic macroangiopathy.

METHODS

There were 378 Type 2 diabetic patients enrolled in this study. A single nucleotide polymorphism in the promoter region (C-106T) was genotyped and the AR protein content of erythrocytes measured by ELISA.

RESULTS

There were no significant differences in genotypic or allelic distribution in patients with or without ischaemic heart diseases, but there was a significant increase in the frequency of the CT + TT genotype and T allele in patients with stroke (P = 0.019 and P = 0.012). The erythrocyte AR protein content was increased in patients with the CT and TT genotype compared with those with the CC genotype. After adjustment for age, duration of diabetes, body mass index, systolic blood pressure, HbA1c, and serum creatinine, triglycerides, and total cholesterol in multivariate logistic-regression models, the association between this AR genotype and stroke remained significant.

CONCLUSIONS

Our results suggest that the CT or TT genotype of the AR gene might be a genetic marker of susceptibility to stroke in Type 2 diabetic patients. This observation might contribute to the development of strategies for the prevention of stroke in Type 2 diabetic patients.

Oxidative stress, advanced glycation end product, and coronary artery calcification in hemodialysis patients

Coronary artery calcification is an index of the severity of atherosclerotic vascular disease, and may predict future adverse cardiovascular events in uremic patients undergoing hemodialysis (HD). HD patients are exposed to oxidative stress, and show high plasma levels of advanced glycation end products (AGEs). The association between oxidative stress, AGEs, established cardiovascular risk factors, and coronary artery calcification score (CACS) was studied in 225 HD patients (123 male, 102 female patients). CACS was measured by using multi-detector row computed tomography. Age, systolic blood pressure, calcium, calcium x phosphate, malondialdehyde, lipid peroxides, and pentosidine were significantly and positively correlated with CACS. Duration on HD tended to be positively correlated with CACS. From the independent variables included in the forward stepwise multiple linear regression analysis, only age, systolic blood pressure, lipid peroxides, calcium, and pentosidine were independently associated with CACS. The odds ratios for past history of coronary artery disease and the presence of diabetes mellitus for high CACS (> or =100) were 6.25 (95% confidence interval; 1.83-21.4) and 2.03 (95% confidence interval; 1.02-4.05), respectively. The plasma pentosidine was significantly and positively correlated with indoxyl sulfate. In conclusion, in addition to such traditional cardiovascular risk factors as past history, diabetes mellitus, aging, systolic blood pressure and calcium overload, oxidative stress (lipid peroxides), and AGE (pentosidine) are associated with extensive coronary artery calcification in HD patients. Lipid peroxidation and glycoxidation may be involved in the pathogenesis of coronary artery calcification.

AUTOINDUCTION OF MKC-963 [(R)-1-(1-CYCLOHEXYLETHYLAMINO)-4-PHENYLPHTHALAZINE] METABOLISM IN HEALTHY VOLUNTEERS AND ITS RETROSPECTIVE EVALUATION USING PRIMARY HUMAN HEPATOCYTES AND CDNA-EXPRESSED ENZYMES

MKC-963, (R)-1-(1-cyclohexylethylamino)-4-phenylphthalazine, a potent inhibitor of platelet aggregation, was synthesized and used in clinical trials in the 1990s. In the process of clinical study, it was found that urinary excretion ratios for 6beta-hydroxycortisol and free cortisol increased significantly in parallel with decreases in the plasma concentrations of MKC-963 after repeated oral administration of the compound to healthy volunteers. These findings suggested that MKC-963 caused autoinduction (defined as the ability of a drug to induce enzymes that enhance its own metabolism, resulting in dispositional tolerance) in humans, and clinical studies using the compound were stopped. This experience prompted us to reevaluate the effects of this compound on CYP3A4 using primary human hepatocytes and cDNA-expressed human cytochrome P450 (P450) enzymes to determine whether the autoinduction of MKC-963 metabolism in humans could have been predicted if these in vitro systems had been used for the evaluation of MKC-963 in the preclinical study. The results of in vitro study showed that MKC-963 increased CYP3A4 mRNA expression level and activity of testosterone 6beta-hydroxylation to extents similar to those observed with rifampicin in primary human hepatocytes. In addition, approximately 90% of the MKC-963 metabolism in human liver microsomes was estimated to be attributable to CYP3A4. These in vitro findings are in good agreement with the results of clinical study, suggesting that studies using human hepatocytes and cDNA-expressed human P450s are useful for assessing the autoinductive nature of compounds under development before starting clinical studies.

Advanced glycation end product modification of bone proteins and bone remodelling: hypothesis and preliminary immunohistochemical findings

BACKGROUND

The process of bone remodelling is disturbed in the development of osteoporosis.

OBJECTIVE

To investigate if proteins in osteoporotic bone are modified by advanced glycation end products (AGEs), and whether these alterations are related to measures of bone remodelling based on histomorphometric findings.

METHODS

Bone specimens taken from the iliac crest by bone biopsy of eight osteoporotic patients were investigated by histomorphometry and by immunohistochemical staining with the AGEs imidazolone and N(epsilon)-carboxymethyllysine.

RESULTS

Both AGEs were found in all bone specimens. The intensity of staining correlated with patient age. The percentage of bone surface covered with osteoblasts showed a significantly negative correlation with the staining intensity of both AGEs.

CONCLUSIONS

It is known that AGEs can regulate proliferation and differentiation of osteoblastic cells and that AGE-specific binding sites are present in cultured osteoblast-like cells. Moreover, AGE induced biological effects in these cells might be mediated by RAGE (receptor of AGE) or by other AGE receptors in different stages of osteoblast development. The inverse relation between AGE staining intensity and the percentage of bone surface covered with osteoblasts in the trabecular bone may provide evidence that AGE modification of bone proteins disturbs bone remodelling.

N2-carboxyethyl-2′-deoxyguanosine, a DNA glycation marker, in kidneys and aortas of diabetic and uremic patients

Advanced glycation end product (AGE)-mediated modification of proteins is enhanced both in the kidneys and aortas of diabetic and uremic patients. However, AGE modification of deoxyribonucleic acid (DNA) has not yet been reported in these patients. We performed immunohistochemistry of kidneys and aortas using a monoclonal antibody against N(2)-carboxyethyl-2'-deoxyguanosine (CEdG), a marker of AGE-linked DNA. A total of 20 kidneys and 20 aortas were obtained by autopsy. The kidney samples consisted of two groups: nondiabetic nonkidney disease (control) and diabetic nephropathy. The aorta samples consisted of four groups: nondiabetic nonkidney disease (control), diabetes, hemodialysis, and diabetic hemodialysis. In the kidneys CEdG was detected predominantly in the nuclei of epithelial cells, mesangial cells, and endothelial cells of the glomeruli, parietal epithelial cells, and tubular cells. The number of CEdG-positive cells in the glomeruli was significantly increased in diabetic nephropathy compared with control. In the aortic walls, CEdG was detected predominantly in the nuclei of macrophages and myofibroblasts. The number of CEdG-positive cells in the aorta was significantly increased in hemodialysis patients and diabetic hemodialysis patients compared with control. The highest number of CEdG-positive cells in the aorta was observed in diabetic hemodialysis patients. In conclusion, AGE-mediated modification of DNA is enhanced in the kidney of diabetic nephropathy and the aorta of uremic atherosclerosis, and may induce a loss of genetic integrity in these diseases.

Thermoluminescence of terbium sensitised by samarium in CaF2

Thermoluminescence (TL) in sintered CaF2 doped with Tb4O7 has been studied for UV and X-ray irradiation. Three TL glow peaks for the Tb4O7 doped sample appeared in the temperature regions of about (1) 347-353 K, (2) 378-383 K and (3) 453-458 K, when heated at a rate of 20 K min(-1) after UV or X-ray irradiation at room temperature. It has been found that the 378 K peak intensity of the samples co-doped with Tb4O7 and Sm2O3 became stronger when compared with those doped with only terbium or samarium ions, and the TL peaks of (1) 347-353 K and (3) 453-458 K were not observed. The intensity of the 378 K peak of the co-doped sample was 12.9 times that of the sample doped only with Tb4O7. From the TL spectra and the excitation and emission spectra of photoluminescence for the CaF2 doped activators, it is concluded that the TL of Tb3+ ions is sensitised by the existence of Sm3+ ions. The 378 K TL peak may also be suitable for UV radiation dosimetry.

Pilomatrix carcinoma of the axilla: CT and MRI features

Pilomatrix carcinoma, a rare malignant soft tissue tumour, is the malignant variant of pilomatricoma. We report a case of pilomatrix carcinoma of the axilla. CT demonstrated a well-circumscribed, sand-like calcified mass. MRI showed diffusely inhomogeneous, mixed signal intensities with inhomogeneous enhancements. The MRI findings were different from those previously reported for pilomatricoma.

Effect of advanced glycation end products on endotoxin-induced TNF-alpha, IL-1beta and IL-8 in human peripheral blood mononuclear cells

BACKGROUND/AIMS

Advanced glycated end products (AGE) are endogenous proteins that have formed covalent complexes with sugars by a nonenzymatic process. Being proinflammatory molecules, AGE are thought to contribute to chronic systemic and local inflammatory processes associated with pathological changes in various diseases. In patients with end-stage renal disease, AGE are believed to play a role in the progression of atherosclerosis and worsening of renal failure. In patients receiving hemodialysis, AGE are thought to contribute to the inflammatory components of the therapy, particularly in diabetic patients.

METHODS

In the present study, AGE were produced using 5% human serum albumin (HSA) and 50% glucose, both used for intravenous infusion into humans and both released after strict control for endotoxin content. The presence of AGE formed by HSA and glucose was confirmed using 2 independent assays. The inflammatory properties of these AGE were assessed using synthesis and release of the proinflammatory cytokines interleukin-1 (IL-1), tumor necrosis factor (TNF) and IL-8, a chemokine.

RESULTS

Alone, AGE did not induce these cytokines from peripheral blood mononuclear cells (PBMC) obtained from 14 healthy human donors. However, in the presence of 1 or 10 ng/ml of endotoxin, AGE augmented the production of IL-1 and TNF above that induced by endotoxin alone. Although the amount of augmentation of LPS-induced cytokines by AGE varied between the blood donors, the response was consistently observed and reached statistical significance. The augmentation of cytokine production was confirmed using AGE prepared with different lots of HSA and glucose.

CONCLUSION

These results demonstrate that in the strict absence ofendotoxins, AGE are formed that do not stimulate cytokine production from PBMC of healthy donors, however, AGE significantly augment the synthesis and release of proinflammatory cytokine in the presence of low concentrations of endotoxins. The data suggest that renal replacement therapies should consider the role of microbial products in potentiating the biological consequences of naturally formed AGE and their potential to contribute to systemic and local inflammation in renal replacement therapies. Therefore, although the formation of AGE is unavoidable, excluding microbial products during renal replacement therapy should reduce the pathological consequences of AGE.

Impaired renal excretion of 6-hydroxy-5,7-dimethyl-2-methylamino-4-(3-pyridylmethyl) benzothiazole (E3040) sulfate in breast cancer resistance protein (BCRP1/ABCG2) knockout mice

Murine breast cancer resistance protein 1 (Bcrp1) is expressed in the brush-border membrane of proximal tubule cells of the kidney. The purpose of the present study is to investigate whether Bcrp1 could be involved in the urinary excretion of the human BCRP substrates, 6-hydroxy-5,7-dimethyl-2-methylamino-4-(3-pyridylmethyl) benzothiazole sulfate (E3040S) and 4-methylumbelliferone sulfate (4MUS), using Bcrp1(-/-) mice. E3040S and 4MUS were given to the mice by intravenous infusion, and plasma and kidney concentrations and the urinary excretion rate were determined. Knockout of Bcrp1 did not affect the creatinine clearance [7.17 +/- 1.00 and 8.66 +/- 2.02 ml/min/kg for Bcrp1(-/-) and wild-type mice, respectively]. The renal clearance of E3040S was 2.4-fold lower in Bcrp1 (-/-) mice compared with wild-type mice (2.74 +/- 0.41 versus 6.55 +/- 0.52 ml/min/kg). The concentration of E3040S in the kidney was increased in Bcrp1(-/-) mice compared with that in wild-type mice (55.5 +/- 10.5 versus 19.4 +/- 2.7 nmol/g kidney, respectively). In contrast, knockout of Bcrp1 did not affect the pharmacokinetic parameters of 4MUS, although 4MUS was predominantly excreted in the urine. This is to our knowledge the first demonstration of involvement of Bcrp1 in the renal secretion of organic sulfates. However, taking the results of 4MUS into consideration, the renal secretion of organic sulfates cannot be accounted for solely by Bcrp1, and transporters other than Bcrp1 are also involved.

Factors affecting clinical outcome of patients who undergo transcatheter arterial embolisation in splenic injury

Transcatheter arterial embolisation (TAE) offers a less invasive approach to traditional laparotomy for the management of bleeding in the context of blunt splenic injury. This is a retrospective review study to identify clinical factors associated with clinical outcome of the patients who underwent this procedure. Of 65 patients with splenic injuries at our institution, 26 patients underwent TAE for management of bleeding. The following factors were assessed to determine their relationship to procedure outcomes: American Association for the Surgery of Trauma (AAST) grade, complications, age, shock index, injury severity score (ISS), haemoglobin (Hb), haematocrit (Ht), prothrombin time (PT), activated partial thromboplastin time (APTT), systolic blood pressure (BP), BP changes during TAE, blood transfused before TAE and timing of TAE. The overall good clinical outcome rate was 73.1% (19/26). Of the factors we assessed, absence of concomitant pelvic injury, higher Hb, higher Ht, higher BP, greater increases in BP during TAE and a decreased requirement for blood transfusions before TAE were associated with good clinical outcome of the patients who underwent TAE in splenic injury.

Functional Characterization of Single Nucleotide Polymorphisms with Amino Acid Substitution in CYP1A2, CYP2A6, and CYP2B6 Found in the Japanese Population

As a part of the studies conducted by the Pharma SNPs Consortium (PSC), the enzyme activities of CYP1A2, CYP2A6 and CYP2B6 variants with altered amino acids as a result of single nucleotide polymorphisms (SNPs) found among the Japanese population were analyzed under a unified protocol using the same lots of reagents by the laboratories participating in the PSC. Mutations in CYP1A2, CYP2A6 and CYP2B6 were introduced by site-directed mutagenesis and the wild type and mutated CYP molecules were expressed in Escherichia coli. The expressed cytochrome P450s were purified and the enzyme activities were measured in reconstitution systems. CYP1A2 and CYP1A2Gln478His did not show any differences in 7-ethoxyresorufin O-deethylase activity. CYP2A6 and CYP2A6Glu419Asp metabolized coumarin to form 7-hydroxycoumarin in a similar manner, whereas CYP2A6Ile471Thr showed low activity compared to the wild-type CYP2A6. CYP2B6, CYP2B6Pro167Ala and CYP2B6Arg487Cys showed the same activity for 7-ethoxy-4-triflouromethyl-coumarin O-deethylation. However, CYP2B6Gln172His was roughly twice as active as CYP2B6 and the other CYP2B6 variants for 7-ethoxy-4-triflouromethylcoumarin O-deethylation activity. Although higher inter- and intra-laboratory variations were observed for the calculated Km and V(max) values because the studies were conducted in several different laboratories, the degree of variations was reduced by the increased number of analyses and the adoption of a simple analysis system.

Impact of drug transporter studies on drug discovery and development

Drug transporters are expressed in many tissues such as the intestine, liver, kidney, and brain, and play key roles in drug absorption, distribution, and excretion. The information on the functional characteristics of drug transporters provides important information to allow improvements in drug delivery or drug design by targeting specific transporter proteins. In this article we summarize the significant role played by drug transporters in drug disposition, focusing particularly on their potential use during the drug discovery and development process. The use of transporter function offers the possibility of delivering a drug to the target organ, avoiding distribution to other organs (thereby reducing the chance of toxic side effects), controlling the elimination process, and/or improving oral bioavailability. It is useful to select a lead compound that may or may not interact with transporters, depending on whether such an interaction is desirable. The expression system of transporters is an efficient tool for screening the activity of individual transport processes. The changes in pharmacokinetics due to genetic polymorphisms and drug-drug interactions involving transporters can often have a direct and adverse effect on the therapeutic safety and efficacy of many important drugs. To obtain detailed information about these interindividual differences, the contribution made by transporters to drug absorption, distribution, and excretion needs to be taken into account throughout the drug discovery and development process.

In vitro activation of 7-benzyloxyresorufin O-debenzylation and nifedipine oxidation in human liver microsomes

1. The effects of substrate concentration and enzyme source (human liver microsomes and recombinant cytochrome P450s, CYP) on the activation of 7-benzyloxyresorufin O-debenzylation and nifedipine oxidation were investigated. 2. 7-Benzyloxyresorufin O-debenzylase activity in human liver microsomes was inhibited by a monoclonal antibody against CYP2B6 and a polyclonal antibody against CYP3A2 by 53-69 and 19-44%, respectively, suggesting that CYP2B6 and CYP3A4 mainly catalyse 7-benzyloxyresorufin O-debenzylation in human liver microsomes. 3. 7-Benzyloxyresorufin O-debenzylase activity at 0.2-5 micro M substrate concentrations in human liver microsomes was increased by the addition of alpha-naphthoflavone, quinidine, testosterone and progesterone, and the V(max) of 7-benzyloxyresorufin O-debenzylation increased with increasing alpha-naphthoflavone concentrations, whereas the K(m) remained constant. Additionally, 7-benzyloxyresorufin O-debenzylation by recombinant CYP3A4 was increased by the addition of alpha-naphthoflavone, testosterone and progesterone but not by quinidine, whereas no chemicals tested could activate the O-debenzylation of 7-benzyloxyresorufin by CYP2B6. 4. The K(m) for nifedipine oxidation activity by CYP3A4 decreased by the addition of progesterone, whereas the V(max) remained constant. Quinidine and testosterone increased 7-benzyloxyresorufin O-debenzylase and nifedipine oxidase activities, respectively, in human liver microsomes, whereas activation was not observed in CYP3A4. 5. The results suggest that in vitro activation patterns are substrate dependent and that selection of the enzyme source can influence the activation phenomenon.

A case with HER2-overexpressing breast cancer completely responded to humanized anti-HER2 monoclonal antibody

This is a case report of a 57-year-old woman with a history of primary carcinoma of the right breast with metastases to the contralateral axillary lymph node. After a partial response (PR) was induced by high-dose chemotherapy with peripheral blood stem cell transplantation, she underwent mastectomy with biopsy of the bilateral axillary lymph nodes. Six months after surgery, the patient had multiple lung metastases. She was then treated with five cycles of fluorouracil, mitoxantrone and vindesine. Although a PR was achieved, further chemotherapy could not be given because of cardiac dysfunction. Since immunohistochemical staining for the HER2 gene product was strongly positive on the surface of primary tumor cells, humanized anti-HER2 monoclonal antibody (trastuzumab) was given intravenously. The metastatic lesion decreased in size and finally appeared to be only cicatricial. Twenty-one months after the initial administration of trastuzumab, the pulmonary lesion was excised. The pathological examination revealed no tumor cells in the resected specimen so further treatment was stopped. The relapse-free state has continued for 24 months after the pulmonary resection.

[Reference values of serum lipid]

The guideline for the reference value of serum lipid(total cholesterol, LDL-cholesterol, HDL-cholesterol and triglyceride) was proposed by the Japan Atherosclerosis Society in 1997. These values are utilized for the diagnosis and treatment of hyperlipidemia to protect patients from ischemic heart disease. The upper limit of reference value was not determined by the 95 percentile range from healthy subjects, but on the basis of clinical data on serum lipid in the Japanese. This way to determine the reference value will be suitable in case of lipid, because there is a tendency to increase cholesterol level in the Japanese for these thirty years. The standardization for each lipid assay is crucial. The CDC-established Reference Methods for measuring total cholesterol(TC), HDL-C. LDL-C, and triglyceride(TG) are used to set reference values for the serum pools used for LSP(Lipid Standardization Panel) standardization. In Japan, the routine methods for cholesterol and triglyceride have been proposed by the special committee in the Japan Society of Clinical Chemistry. In contrast, homogeneous assay for HDL- and LDL-C, which are used routinely at present, have still some problems in the point of accuracy. A new ELISA for Lp(a) has been developed using antibody not reacting to kringle IV type 2. Its standardized assay, thus, will be available sooner or later. With respect to other lipid-related test such as RLP(remnant-like particles) and oxidized LDL, it is necessary to accumulate more clinical data for the determination of reference value.

Localization of imidazolone in the peritoneum of capd patients: a factor for a loss of ultrafiltration

The presence of dicarbonyl compounds, potent precursors of advanced glycation end products (AGEs), has been recognized in unused peritoneal dialysis (PD) fluids. Accumulation of AGEs has been implicated in the alteration of peritoneal membrane properties during continuous ambulatory peritoneal dialysis (CAPD) therapy. To determine whether imidazolone, an AGE specifically derived from 3-deoxyglucosone (3-DG), contributes to a decrease in ultrafiltration (UF) capacity of the peritoneal membrane in CAPD patients, we immunohistochemically evaluated the localization of imidazolone in peritoneal tissues from CAPD patients. Mesothelial thickening in the peritoneum was found in six of seven CAPD patients. Imidazolone distinctly accumulated in peritoneal tissues of CAPD patients, whereas it was hardly detected in those of patients with nonrenal disease. CAPD patients with a low UF capacity showed more extensive peritoneal deposition of imidazolone and more pronounced mesothelial thickening than those with a normal UF capacity. A CAPD patient with sclerosing peritonitis showed the most abundant localization of imidazolone among all CAPD patients. Gas chromatography/mass spectrometry showed that unused PD fluids contained high 3-DG concentrations (mean, 34.6 +/- 14.1 [SD] microgram/mL). In conclusion, the accumulation of imidazolone was noted in peritoneal tissues of CAPD patients, which preceded a decrease in UF capacity. Imidazolone modification may alter the quality of peritoneal membranes, presumably leading to a loss of UF and finally the development of sclerosing peritonitis.

Metabolism and interaction of bisphenol A in human hepatic cytochrome P450 and steroidogenic CYP17

The metabolism of bisphenol A (BPA) was determined for 11 forms of human hepatic cytochromes P450 (CYPs) expressed in the yeast Saccharomyces cerevisiae and for human steroidogenic CYP17 expressed in Escherichia coli. Additionally, the effect of BPA on the progesterone 17alpha-chydroxylase activity of CYP17 was investigated. CYP2C18 catalyzed BPA metabolism most efficiently, followed by CYP2C19 and CYP2C9. CYP2C9 and CYP2C18 exhibited the highest affinity (Km=3.9 microM) for BPA metabolism. The Vmax of CYP2C18 (8.10 nmol x min(-1) x nmol CYP(-1)) was 5 times higher than that of CYP2C9. Although the Vmax of CYP2C19 was 1.5 times higher than that of CYP2C18, the affinity of CYP2C19 was 12 times lower than that of CYP2C9 and CYP2C18. Therefore the intrinsic clearance (Vmax/Km) of CYP2C18 was more than 5 times higher than that of CYP2C9 and CYP2C19. On the other hand, BPA exhibited a competitive-type inhibition of the progesterone 17alpha-hydroxylase activity of CYP17 with a Ki value of 71 microM, whereas no metabolism of BPA by CYP17 was detected. These results suggest that BPA is mainly metabolized by the CYP2C subfamily in human liver, and that BPA inhibits human steroidogenic CYP17 activities.

Advanced glycation end products (AGEs)-induced expression of TGF-beta 1 is suppressed by a protease in the tubule cell line LLC-PK1

BACKGROUND

Advanced glycation end products (AGEs) are assumed to play a key role in diabetic nephropathy (DN). Since little is known about their action in tubule cells, we investigated in LLC-PK1 cells: (i) whether AGE-bovine serum albumin (AGE-BSA) affects cell proliferation and expression of transforming growth factor-beta (TGF-beta 1); and (ii) whether the AGE-induced effects can be modulated by trypsin due to interference with its binding proteins at the cell surface.

METHODS

Arrested cells were exposed to vehicle (control), AGE-BSA (19--76 microM) and BSA (38 microM) in the presence or absence of trypsin (0.625--5.0 microg/ml) (2.5 microg/ml) for 24 h. We evaluated cell proliferation by cell count and by [(3)H]thymidine incorporation, TGF-beta 1 expression by reverse transcription-polymerase chain reaction (RT-PCR), and TGF-beta 1 protein by ELISA. In addition, cell accumulation of AGEs was studied by immunohistochemical staining of the AGE imidazolone.

RESULTS

AGE-BSA inhibited [(3)H]thymidine incorporation, lowered cell number and increased cell protein content as well as TGF-beta 1 mRNA and protein as compared with control and BSA. Immunohistochemical staining revealed a marked intracellular accumulation of the AGE imidazolone. Co-incubation of AGE-BSA with trypsin ameliorated the impaired thymidine incorporation, the decreased cell count and the enhanced cell protein content. TGF-beta 1 overexpression was normalized, while TGF-beta 1 protein declined insignificantly. Intracellular imidazolone accumulation was strikingly suppressed.

CONCLUSIONS

In the tubule cell line LLC-PK1, AGE-BSA exerts an antiproliferative effect, most probably due to TGF-beta 1 overproduction. The co-administration of trypsin abrogated this alteration, very likely as a result of an interaction with AGE-binding protein(s), which is supported by the decreased intracellular AGE accumulation. These findings may be the starting point for the development of specific proteolytic enzymes to interfere with the interaction between AGEs and their receptors/binding proteins.