Dehydroepiandrosterone sulfate and estradiol in men with diabetic nephropathy.
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Biomedical subjects
Publications and source records attributed to M Nakajima.
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BACKGROUND: Human eosinophils contain two eosinophil ribonucleases, eosinophil cationic protein (ECP) and eosinophil-derived neurotoxin (EDN). In rats, 8 homologues of human ECP and EDN have been identified. To clarify the biological activity of rat eosinophil ribonucleases, we cloned rat eosinophil-associated ribonuclease (EAR)-1/rat ribonuclease 7 and rat EAR-2/rat ribonuclease 4, and produced recombinant rat pre-EAR-1 and pre-EAR-2 in a bacterial expression system. METHODS: As we have already cloned the complete nucleotide sequence for rat EAR-1, we determined that for rat EAR-2 cDNA by the rapid amplification of cDNA ends procedure. Recombinant rat pre-EAR-1 and pre-EAR-2 were expressed in Escherichia coli as N-terminal 6 x histidine-tagged proteins, isolated from the insoluble fraction of the cell lysate and purified by a single-step method using an Ni-NTA resin column after solubilization with a 6 M guanidine solution. RESULTS: The deduced amino acid sequence revealed that the molecular weight of EAR-2 containing the signal peptide is 17.3 kD and the isoelectric point is 8.59. The homology in amino acid sequence between rat pre-EAR-2, and human pre-ECP and human pre-EDN is 51 and 53%, respectively. The purified and refolded recombinant rat pre-EAR-1 and pre-EAR-2 showed bactericidal activity against E. coli and Staphylococcus aureus. CONCLUSIONS: These findings suggest that rat EAR-1 and EAR-2 act as host defense factors against bacterial infection in rats.
BACKGROUND AND PURPOSE: Poly(ADP-ribose) polymerase (PARP) is important in modulating inflammation, which has been implicated in cerebral vasospasm after subarachnoid hemorrhage (SAH). We investigated the role of PARP in vasospasm using 3-aminobenzamide (3-AB), a PARP inhibitor, in a rabbit model. METHODS: Twenty-four New Zealand White rabbits were divided into 4 groups: (1) no treatment (control group, n=6); (2) blood injection without pretreatment (SAH-only group, n=6); (3) blood injection with pretreatment by vehicle (SAH+vehicle group, n=6); and (4) blood injection with pretreatment by 3-AB (SAH+3-AB group, n=6). We used the single-hemorrhage model of SAH, injecting autologous arterial blood into the cisterna magna. Angiography was performed before (baseline) and after (day 2) SAH, and the diameter of the basilar artery (BA) was measured. Animals were euthanatized after the second angiogram. After perfusion and fixation, the brains were cut into sections for hematoxylin and eosin and immunohistochemical staining for poly(ADP-ribosyl)ation. RESULTS: In the control group, there were no differences in the BA lumen caliber between baseline and day 2 (96.8+/-10.4%). Cerebral vasospasm in the SAH+3-AB group (88.2+/-6. 2%) was remarkably attenuated in comparison with that in the SAH-only group (64.9+/-8.0%) and the SAH+vehicle group (65.6+/-10. 8%). The BA in the SAH+3-AB group showed less corrugation of the tunica elastica interna than that in the SAH-only and SAH+vehicle groups. Staining for poly(ADP-ribosyl)ation was markedly inhibited in smooth muscle and adventitial cells of the BA in the SAH+3-AB group compared with other groups. CONCLUSIONS: Inhibiting ADP-ribosylation attenuates cerebral vasospasm after SAH in rabbits, and PARP activation may play an important role in the development of cerebral vasospasm.
BACKGROUND AND PURPOSE: The effects of aging on cerebral vasospasm after subarachnoid hemorrhage (SAH) remain to be elucidated. The aim of this study was to clarify age-related differences of vasospasm and of papaverine reactivity in the responses of basilar arteries after SAH in rabbits. METHODS: Rabbits receiving a single injection of arterial blood into the cisterna magna were divided into 3 groups: young (2 to 3 months old), adult (6 to 9 months old), and old (20 to 40 months old). Vertebrobasilar angiograms were obtained before SAH and 1, 2, 4, and 7 days after SAH. Papaverine was administrated selectively via the vertebral artery on day 2, and serial angiography was performed for up to 2 hours. Vessel structures were assessed with light microscopy on days 1, 2, 4, and 7 after SAH and at 10, 30, and 60 minutes after papaverine infusion. RESULTS: Mortality from SAH in old rabbits was 40%, whereas that of young and adult rabbits was 0%. Angiograms revealed that SAH induced maximal constriction of the basilar arteries on day 2 in all age groups, and the constrictions were significantly increased with age at all time points investigated. The degree of dilatation of spastic basilar arteries after intra-arterial papaverine administration significantly decreased with age. Duration of the efficacy of papaverine became significantly shorter with age. Vessel diameter returned to the preinfusion value approximately 120, 60, and 30 minutes after infusion in young, adult, and old rabbits, respectively. Light microscopy in old rabbits showed luminal narrowing and corrugation of the internal elastic lamina not only in the basilar arteries but also in small arteries and intraparenchymal arterioles. CONCLUSIONS: This study suggests that aging increases the degree of vasospasm in rabbits. The impaired reactivity to papaverine with aging might imply the early transition of the aged vessel to the papaverine-resistant chronic stage.
The Notch signalling pathway plays essential roles during the specification of the rostral and caudal somite halves and subsequent segmentation of the paraxial mesoderm. We have re-investigated the role of presenilin 1 (Ps1; encoded by Psen1) during segmentation using newly generated alleles of the Psen1 mutation. In Psen1-deficient mice, proteolytic activation of Notch1 was significantly affected and the expression of several genes involved in the Notch signalling pathway was altered, including Delta-like3, Hes5, lunatic fringe (Lfng) and Mesp2. Thus, Ps1-dependent activation of the Notch pathway is essential for caudal half somite development. We observed defects in Notch signalling in both the caudal and rostral region of the presomitic mesoderm. In the caudal presomitic mesoderm, Ps1 was involved in maintaining the amplitude of cyclic activation of the Notch pathway, as represented by significant reduction of Lfng expression in Psen1-deficient mice. In the rostral presomitic mesoderm, rapid downregulation of the Mesp2 expression in the presumptive caudal half somite depends on Ps1 and is a prerequisite for caudal somite half specification. Chimaera analysis between Psen1-deficient and wild-type cells revealed that condensation of the wild-type cells in the caudal half somite was concordant with the formation of segment boundaries, while mutant and wild-type cells intermingled in the presomitic mesoderm. This implies that periodic activation of the Notch pathway in the presomitic mesoderm is still latent to segregate the presumptive rostral and caudal somite. A transient episode of Mesp2 expression might be needed for Notch activation by Ps1 to confer rostral or caudal properties. In summary, we propose that Ps1 is involved in the functional manifestation of the segmentation clock in the presomitic mesoderm.
We have developed a new method of lipase activation for interesterification, in which lipase, in contact with a hydrocarbon-water interface, has been found to have high interesterification activity in an anhydrous solvent. We have applied this activation method to various lipase and obtained high synthetic activity in n-hexane, and have investigated the effect of various hydrocarbon-water interfaces on the synthetic and hydrolytic activities of lipases. The esterification and/or interesterification activity of lipases tested was improved by this activation method, using an n-tetradecane-water interface. From the initial group of lipases, three representative lipases (from Rhizopus japonicus, Chromobacterium viscosum and porcine pancreas) were selected for further study. The effect of various hydrocarbon-water interfaces on synthetic (interesterification or esterification) activity was studied. We demonstrated that the resulting synthetic activity was affected by the choice of hydrocarbon-water interface and that there were differences in the effects of interfaces on the synthetic activity of these lipases.
Stearic acid modified lipase (from Rhizopus japonicus) exhibited remarkable interesterification activity in n-hexane, but crude native lipase did not. The structure of the fatty acid modified lipase had not been analyzed until now. We analyzed the modified lipase by small-angle X-ray scattering (SAXS) measurements in order to clarify the structure. SAXS measurements showed that the modified lipase consisted of a lipid lamellar structure and implied that the lipase was incorporated into the lamellar structure of stearic acid. The long spacings in the lamellar structures of the modified lipase and stearic acid were measured.
STUDY OBJECTIVE: To investigate the prevalence of asymptomatic infection with Chlamydia pneumoniae in subjectively healthy adults. DESIGN: Prospective study. SETTING: Kawasaki Medical School Hospital in Kurashiki, Japan. PARTICIPANTS: Total of 1,018 asymptomatic healthy adults (age range, 22 to 50 years; mean age, 32.4 years; 482 men and 536 women). MEASUREMENTS AND RESULTS: Nasopharyngeal swab specimens were obtained from all subjects and analyzed by isolation in cell cultures and polymerase chain reaction (PCR) test for C pneumoniae. Serum samples were also obtained and tested for C pneumoniae-specific antibodies by the microimmunofluorescence test. Of 1,018 specimens tested, 14 specimens (1.4%) were judged positive by culture and/or the PCR. Thirteen specimens were PCR positive, and 4 specimens were culture positive. There were three specimens positive by both tests and 11 specimens positive with discrepancies in culture and PCR results. None of the individuals met the serologic criteria for acute infection. Of 1,018 sera tested, 64.1% of men and 58.0% of women had antibody to C pneumoniae. The overall prevalence of antibody was 60.9%. Forty individuals (3.9%) had an IgG titer of > or = 1:512 or IgM titer of > or = 1:16. CONCLUSIONS: Our data suggest that asymptomatic infection with C pneumoniae may occur in subjectively healthy adults.
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The measurement of serum (1-3)-beta-D-glucan (beta-glucan) in cases with deep seated mycosis is a useful diagnostic method. Beta-glucan has usually been measured using two different methods: by an alkali treatment, chromogenic automated kinetic assay (chromogenic assay), and by detergent dilution and heating methods, kinetic turbidimetric assay (turbidimetric assay). However, there are often large discrepancies in the beta-glucan values measured by these two methods. In this study, we reexamined the values of beta-glucan obtained by the two techniques, using 343 serum samples from 146 patients who had been treated in Kawasaki Medical School between January 1999 and May 1999, and then analyzed the reasons for the differences. Serum beta-glucan results measured were evaluated by segregating them into three clinical categories: cases with proven deep mycosis, cases with probable deep mycosis and cases without deep mycosis. In addition, the beta-glucan in the samples was suppressed by carboxy-methylated curdlan (CM-curdlan), and then was remeasured to find a non-specific reaction. Although a certain correlation was found between the serum beta-glucan results measured by the two methods, the values measured by the chromogenic assay were, in general, higher than those measured by the turbidimetric assay. There were also many samples in the cases without deep mycosis that showed positive values with the chromogenic assay, but not with the turbidimetric assay. With the turbidimetric assay, the addition of CM-curdlan suppressed the values of beta-glucan in all samples; however, when measured by the chromogenic assay the values in many samples remained high. These results suggest that a non-specific reaction which did not include beta-glucan was detected by the chromogenic assay. Further studies are needed to evaluate the characteristics and comparable usefulness of the two assays.
PURPOSE: We determined the role of endothelin receptors in prostate cancer progression. MATERIALS AND METHODS: We examined 51 prostate cancer specimens obtained at surgery or biopsy for the relationship of endothelin receptor expression determined by immunohistochemical staining with malignant potential. RESULTS: The positive staining rate of endothelin receptor A in the 51 specimens was significantly higher than of endothelin B (71% versus 24%, p <0.0001). The staining rate of receptor A in Gleason score 5 to 10 disease was significantly higher than in Gleason 2 to 4 disease (91% versus 29%, p <0.0001). The overall staining rate of endothelin receptor A in nonorgan confined disease without bone metastasis but with extraprostatic disease was 87% in 23 cases, including 16 of 19 stage T3 (84%) and all 4 stage T4 (100%) cases. This rate was significantly higher than that of organ confined cancer (29%, p = 0.0003). All patients with bone metastasis had positive staining for endothelin receptor A. An especially high rate of intensely positive staining was observed for endothelin receptor A in biopsy specimens with bone metastasis or Gleason sum 8 to 10. Moreover, positive staining was stronger in cancer cells penetrating the prostatic capsule than in those at the primary foci. However, the positive staining rate of endothelin receptor B was not significantly different in organ and nonorgan confined cancer without bone metastasis (12% versus 26%, p = 0.4284), bone metastatic and nonmetastatic cancer (20% versus 36%, p = 0.2619) or the Gleason sum groups (p = 0.0874). CONCLUSIONS: Our results indicate that endothelin receptor A expression may serve as a marker for and have an important role in prostate cancer progression.
Primary malignant fibrous histiocytoma (MFH) of the heart is very rere. We report a case of a primary intracardiac MFH. A 50-year-old woman underwent an operation for congestive heart failure due to left atrial (LA) tumor. Cardiac echocardiogram showed the tumor attached to the septal wall and posterior wall of LA. We extendedly resected the tumor with septal and partially posterior wall and reconstructed there with pericardial substitute. Pathological diagnosis was MFH. Although she did well postoperatively, cardiac echocardiogram showed a recurrent tumor in the LA at 10 days after operation. She developed respiratory failure, and chest and abdominal CT demonstrated metabolism to the lung, liver and bladder at post operative 47 days. At 77 days after operation, she expired. The prognosis of MFH is poor despite surgery. We recommend extended surgery, if the LA tumor had wide base attached to the septal or posterior wall.
Phenytoin, 5,5-diphenylhydantoin, is a widely used anticonvulsant agent with a variety of toxicities, including drug interactions. The formation of four oxidative metabolites, 4'-hydroxylated (4'-HPPH), 3'-hydroxylated (3'-HPPH), a catechol (3',4'-diHPPH), and the 3',4'-dihydrodiol form of phenytoin was examined in rat liver microsomes. In 11 cDNA-expressed rat P450 enzymes tested, CYP2C6 had the highest activities in 4'- and 3'-HPPH formation from phenytoin, followed only by CYP2C11. In contrast, CYP2C11 had high activity for 3',4'-diHPPH formation from 4'-HPPH, followed by CYP2C6. The rates of 4'-HPPH and 3',4'-diHPPH formation from phenytoin in liver microsomes in the presence of NADPH were significantly decreased by oral administration of phenytoin (300 mg/kg for 20 days) to rats, despite the increase in P450 contents. However, the cumene hydroperoxide-supported formation of 3',4'-dihydrodiol and 4'-HPPH from phenytoin was induced by phenytoin administration. Hydrogen peroxide formation in reaction mixtures with NADPH was induced by the administration of phenytoin; however, the coupling ratio of phenytoin oxidation was decreased in phenytoin-induced liver microsomal P450 systems. These results suggested that phenytoin could not stimulate its own apparent oxidative metabolism by liver P450s induced with phenytoin administration. The increase of unmetabolized phenytoin and byproducts of oxygen generated in the phenytoin-induced liver microsomal P450 system may be involved in phenytoin-related drug toxicity.
A 58-year-old man was diagnosed as having advanced gallbladder cancer (T4, P0, H0, N0, stage IVa) with direct invasion to the liver, transverse colon and duodenum. Therefore, extended cholecystectomy and bile duct resection with a partial resection of the transverse colon and the duodenum were performed in March 1992. Histopathological examination revealed moderately differentiated tubular adenocarcinoma of si, ly1, v1, hinf3, binf3, n0. Three years and eight months after the operation, multiple liver metastases were diagnosed by abdominal CT. Repeated hepatic arterial infusion chemotherapy with 5-FU 500 mg/body/w, MMC 4 mg/body/2w and EPI 40 mg/body/4w was performed starting in January 1996. Four months later, the lesions in the liver were reduced in size, and abdominal CT 10 months after the chemotherapy showed a partial response. However, the liver metastasis of the right lobe was enlarged on an abdominal CT in August 1997. Repeated hepatic arterial infusion chemotherapy with the same regimen was performed again starting in March 1998. Ten months later, the liver metastasis was slightly enlarged, but the greater part of the metastasis showed necrosis on an abdominal CT in January 1999. However, peritonitis carcinomatosa was observed later and the patient died 8 years after the operation.
Recently, we have reported that tegafur, an anticancer agent, is biotransformed into active drug 5-fluorouracil (5-FU) by cytochromes P450 1A2, 2A6, and 2C8 in human liver microsomes (T. Komatsu et al., Drug Metab. Dispos, 28: 1457-1463, 2000). Because the conversion of tegafur into 5-FU has also been reported to be catalyzed by cytosolic thymidine phosphorylase (dThdPase), the involvement of human liver microsomes and cytosol and individual differences in 5-FU formation from tegafur were investigated. In 14 human samples, the mean rates of 5-FU formation in liver microsomes were 5-fold and 2-fold higher than those in liver cytosol at substrate concentrations of 100 microM and 1 mM tegafur, respectively. In the presence of 5-chloro-2,4-dihydroxypyridine, a dihydropyrimidine dehydrogenase inhibitor, the rates of 5-FU formation by the combination of liver microsomes and cytosol showed 5- and 3-fold interindividual differences at 100 microM and 1 mM tegafur, respectively. Kinetic analysis of human liver cytosolic 5-FU formation indicated an apparent higher Km value (16 +/- 4 mM) than that of liver microsomes (1.8 +/- 0.3 mM) with similar Vmax values. Human liver cytosolic 5-FU formation was confirmed to be catalyzed by dThdPase with correlation and chemical inhibition studies. These results suggested that 5-FU formation from tegafur in human liver was mainly catalyzed by microsomal P450 at low concentrations of tegafur, but the contribution of cytosolic 5-FU formation by dThdPase would be important at high concentrations.
Tegafur, an anticancer prodrug, is reported to be bioactivated to 5-fluorouracil (5-FU) by cytochrome P450 (P450) enzymes. Liver microsomal P450 enzymes involved in the biotransformation of tegafur into 5-FU in rats and the effect of tegafur in vivo on P450 levels in rats were investigated. Of 12 cDNA-expressed rat P450 enzymes tested, CYP1A2, CYP3A1, and CYP2C11 had high 5-FU formation rates from 100 microM and 1.0 mM tegafur concentrations. The contributions of CYP1A, CYP2C, and CYP3A enzymes to 5-FU formation in male rat liver microsomes were supported by immunoinhibition studies. 5-FU formation from tegafur, at substrate concentrations of 100 microM and 1.0 mM, was increased by intraperitoneal treatment of tegafur (50 mg/kg for 5 days) as well as by beta-naphthoflavone, phenobarbital, and dexamethasone. Orally administered tegafur (100 mg/kg daily for 20 days) caused the induction of CYP2B (5-fold) and of CYP1A and CYP3A (approximately 2-fold) and of 5-FU formation (approximately 2-fold) in rat liver microsomes. These results suggest that CYP1A and CYP3A enzymes, autoinduced by tegafur, have important roles in 5-FU formation from tegafur in rat liver microsomes. Coadministration of tegafur and P450-inducing drugs could markedly enhance the biotransformation of tegafur into 5-FU via P450 induction.
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This Phase I study of MMI270, an p.o. administered matrix metalloproteinase inhibitor, assessed toxicity, pharmacokinetics, and tumor response data and investigated markers of biological activity to recommend a dose for Phase II studies. MMI270 was administered continuously at seven dose levels (50 mg once daily to 600 mg three times/day). Patients were evaluated for toxicity and tumor response, and blood and urine samples were taken for pharmacokinetics, bone resorption markers, direct targets of the inhibitor [matrix metalloproteinase-2 (MMP-2), MMP-8, and MMP-9], indirect targets [tissue inhibitor of metalloproteinase-1 (TIMP-1), TIMP-2, basic fibroblast growth factor, vascular endothelial growth factor, vascular cell adhesion molecule-1, soluble urokinase plasminogen activator receptor, and cathepsins B and H] and for a tumor necrosis factor-alpha cytokine release assay. Ninety-two patients were entered. There was no myelotoxicity. Eighteen patients developed a widespread maculopapular rash, which increased in frequency and severity at doses > or = 300 mg bid. Thirty nine patients developed musculoskeletal side effects, which were related to duration of treatment, not to dose level. Pharmacokinetics were linear, and MMI270 was rapidly absorbed and eliminated with minimal accumulation on chronic dosing. Sustained plasma concentrations in excess of 4 x mean IC(50) for the target enzymes were observed at dose levels > or = 150 mg bid. There were no tumor regressions; however, 19 patients had stable disease for > or = 90 days. There was a dose-response increase of MMP-2 and TIMP-1 with MMI270. Transient effects on the bone resorption markers were detected. MMI270 was generally well tolerated, with adequate plasma levels for target enzyme inhibition. The two main toxicities were rash, resulting in a maximum tolerated dose of 300 mg bid and musculoskeletal side effects. Biological marker data indicate drug effects. The rise in TIMP-1 suggests that a reflex rise in inhibitors could modify the effects of MMI270. The recommended Phase II dose is 300 mg bid.