Characterization and functional role of rapid- and slow-activating delayed rectifier K+ currents in atrioventricular node cells of guinea pigs

The atrioventricular (AV) node is the only conduction pathway where electrical impulse can pass from atria to ventricles and exhibits spontaneous automaticity. This study examined the function of the rapid- and slow-activating delayed rectifier K⁺ currents (I_Kr and I_Ks) in the regulation of AV node automaticity. Isolated AV node cells from guinea pigs were current- and voltage-clamped to record the action potentials and the I_Kr and I_Ks current. The expression of I_Kr or I_Ks was confirmed in the AV node cells by immunocytochemistry, and the positive signals of both channels were localized mainly on the cell membrane. The basal spontaneous automaticity was equally reduced by E4031 and HMR-1556, selective blockers of I_Kr and I_Ks, respectively. The nonselective β-adrenoceptor agonist isoproterenol markedly increased the firing rate of action potentials. In the presence of isoproterenol, the firing rate of action potentials was more effectively reduced by the I_Ks inhibitor HMR-1556 than by the I_Kr inhibitor E4031. Both E4031 and HMR-1556 prolonged the action potential duration and depolarized the maximum diastolic potential under basal and β-adrenoceptor-stimulated conditions. I_Kr was not significantly influenced by β-adrenoceptor stimulation, but I_Ks was concentration-dependently enhanced by isoproterenol (EC₅₀: 15 nM), with a significant negative voltage shift in the channel activation. These findings suggest that both the I_Kr and I_Ks channels might exert similar effects on regulating the repolarization process of AV node action potentials under basal conditions; however, when the β-adrenoceptor is activated, I_Ks modulation may become more important.

[Two Cases of Convulsive Seizures after Cardiac Surgery Suspiciously Caused by Tranexamic Acid Administration in Patients on Chronic Hemodialysis]

Tranexamic acid (TA), an antifibrinolytic agent, is commonly used in cardiac surgery with cardiopulmo- nary bypass to reduce bleeding. We report two cases of convulsive seizures after cardiac surgery with chronic kidney disease on hemodialysis. The two patients underwent aortic valve replacement, one for aortic valve regurgitation and another for aortic valve stenosis, with cardiopulmonary bypass uneventfully. A total dose of 8 g of TA was administered intravenously; 4 g during and 4 g after cardiopulmonary bypass. Both patients developed two episodes of gener- alized convulsive seizures post-operative day 1, which were suppressed by administration of diazepam intra- venously. The blood test, brain CT and electroenceph- alogram revealed no significant abnormalities. They were discharged without any neurological complica- tions. The high dose of TA was considered to have caused the seizures, since in previous reports the use of TA during surgery was associated with increased risk for postoperative seizures. It was demonstrated that approximately 40 to 70% of TA is excreted in the urine following intravenous administration. We posit that this might have led to excessive serum concen- tration of TA in our patients. Therefore, the dosage of TA should be decreased judiciously in patients with chronic kidney disease especially on hemodialysis to prevent postoperative seizures.

Synthesis and characterization of nitrogen-functionalized graphene oxide in high-temperature and high-pressure ammonia

Successful N-functionalization of graphene oxide with high-temperature and high-pressure ammonia obtaining over 10% N-doping level.

Phase I and biomarker study of OPB-51602, a novel signal transducer and activator of transcription (STAT) 3 inhibitor, in patients with refractory solid malignancies

BACKGROUND

The aim of this study was to determine the maximum-tolerated dose (MTD), safety, pharmacokinetics, and pharmacodynamics of OPB-51602, an oral, direct signal transduction activator of transcription 3 (STAT3) inhibitor, in patients with refractory solid tumors.

PATIENTS AND METHODS

Three cohorts were studied: cohort A, a sequential dose escalation of OPB-51602 administered intermittently (days 1-14 every 21 days); cohort B, an expansion cohort evaluating the dose lower than the MTD; cohort C, evaluating continuous daily dosing.

RESULTS

Fifty-one patients were studied at 2, 4, and 5 mg per day dosing. The MTD was 5 mg; first-cycle dose-limiting toxicities (DLTs) were grade 3 hyponatremia in one patient, and grade 3 dehydration in another. Intermittent dosing of both 2 and 4 mg doses were tolerable, and the recommended phase II dose was 4 mg. Cohort B investigated 4 mg intermittently, whereas cohort C investigated 4 mg continuously. Common toxicities included fatigue, nausea/vomiting, diarrhea, anorexia, and early-onset peripheral neuropathy. Drug-induced pneumonitis occurred in two patients in cohort C. Continuous dosing was associated with a higher incidence of peripheral neuropathy and a lower mean relative dose intensity, compared with intermittent dosing. Steady-state pharmacokinetics was characterized by high oral clearance, mean elimination half-life ranging from 44 to 61 h, and a large terminal-phase volume of distribution. An active metabolite, OPB-51822, accumulated to a greater extent than OPB-51602. Flow cytometry of peripheral blood mononuclear cells demonstrated pSTAT3 (Tyr(705)) inhibition following exposure. Two patients achieved partial responses at 5 mg intermittently and 4 mg continuously; both had epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC) with prior EGFR tyrosine kinase inhibitor exposure.

CONCLUSION

OPB-51602 demonstrates promising antitumor activity, particularly in NSCLC. Its long half-life and poorer tolerability of continuous dosing, compared with intermittent dosing, suggest that less frequent dosing should be explored.

CLINICALTRIALSGOV IDENTIFIER

NCT01184807.

A drug formulation using an alginate hydrogel matrix for efficient oral delivery of the manganese porphyrin-based superoxide dismutase mimic

In order for patients to avail of the therapeutic benefits of antioxidant drugs efficiently and conveniently, a robust oral delivery system needs to be developed.

[Left ventricular migrating thrombus detected by intraoperative transesophageal echocardiography]

Transesophageal echocardiography (TEE) helps detecting intra-cavity thrombus size, mobility and fragility, which are of great importance in surgical removal of the thrombus. Thrombus characteristics may render surgical thrombectomy incomplete, raising the risk of catastrophic embolization. A 50-year-old man, suffering from congestive heart failure, developed a mobile thrombus in the left ventricle (LV). He was scheduled for a LV thrombectomy. TEE showed two thrombi on the apical side of the left ventricle, measuring 2.1 x 1.3 cm and 2.1 x 1.0 cm each. A surgical removal of these thrombi was performed under cardiopulmonary bypass (CPB). Just before separation from CPB, TEE detected a high echogenic mass in the LV Surgical re-explorations found residual thrombi, whose size, figure and echo signal strength resembled papillary muscles. This experience leads us to advocate repeated search for thrombi using TEE scans, in order to facilitate complete removal of thrombi prior to closing the ventriculotomy, and prior to weaning from CPB.

[Evaluation of the side effects of intravenous patient controlled analgesia after spine surgery]

BACKGROUND

We have adopted intrravenous patient controlled analgesia (IV-PCA) for spine surgery. We could not find reports about detailed examinations of the side effects of IV-PCA using morphine after spine surgery, so we investigated retrospectively side effects in cases using morphine IV-PCA.

METHODS

Eighty-five patients underwent IV-PCA after spine surgery. The contents of PCA pump were morphine 20 mg (= 2 ml), droperidol 2 mg (= 0.8 ml), and saline 77 ml. We fixed continuous infusion at 2 ml x hr(-1), bolus infusion at 2 ml x hr(-1), and lockout time at 15 minutes. Respiration time, SpO2, blood pressure, pulse rate, nausea and vomiting, and VAS were monitored while IV-PCA was in use. When severe side effects were noticed, IV-PCA was discontinued by physician in charge. We judged discontinuation of IV-PCA as occurrence of severe side effects.

RESULTS

IV-PCA was discontinued in seven patients. The causes of discontinuation were nausea and vomiting, hypotension, and bradycardia. Nausea and vomiting was the most common cause and found mostly in women.

CONCLUSIONS

Because IV-PCA was discontinuated in 8.2% of patients, it was thought that its management depending on patients' personal state was necessary to utilize IV-PCA as a method of postoperative analgesia.

Effects of the systemic administration of alendronate on bone formation in a porous hydroxyapatite/collagen composite and resorption by osteoclasts in a bone defect model in rabbits

Several bisphosphonates are now available for the treatment of osteoporosis. Porous hydroxyapatite/collagen (HA/Col) composite is an osteoconductive bone substitute which is resorbed by osteoclasts. The effects of the bisphosphonate alendronate on the formation of bone in porous HA/Col and its resorption by osteoclasts were evaluated using a rabbit model. Porous HA/Col cylinders measuring 6 mm in diameter and 8 mm in length, with a pore size of 100 μm to 500 μm and 95% porosity, were inserted into a defect produced in the lateral femoral condyles of 72 rabbits. The rabbits were divided into four groups based on the protocol of alendronate administration: the control group did not receive any alendronate, the pre group had alendronate treatment for three weeks prior to the implantation of the HA/Col, the post group had alendronate treatment following implantation until euthanasia, and the pre+post group had continuous alendronate treatment from three weeks prior to surgery until euthanasia. All rabbits were injected intravenously with either saline or alendronate (7.5 μg/kg) once a week. Each group had 18 rabbits, six in each group being killed at three, six and 12 weeks post-operatively. Alendronate administration suppressed the resorption of the implants. Additionally, the mineral densities of newly formed bone in the alendronate-treated groups were lower than those in the control group at 12 weeks post-operatively. Interestingly, the number of osteoclasts attached to the implant correlated with the extent of bone formation at three weeks. In conclusion, the systemic administration of alendronate in our rabbit model at a dose-for-weight equivalent to the clinical dose used in the treatment of osteoporosis in Japan affected the mineral density and remodelling of bone tissue in implanted porous HA/Col composites.

The entrapment of kojic oleate in bilayer vesicles

The entrapment of kojic acid and its newly synthesized ester (kojic oleate) has been evaluated. Kojic oleate was synthesized by DCC (N,N'-dicyclohexylcarbodiimide, DCC)/(4-(N,N-dimethylamino)pyridine, DMAP) esterification method and identified by FAB-MS and 1H NMR. The synthesized product was mainly 7-O-kojic oleate with more than 80% yield. It was entrapped in vesicular membrane prepared from 9.5:9.5:1.0 molar ratio of amphiphiles (Span 60, Tween 61 or DPPC), cholesterol and dicetyl phosphate. Kojic acid was encapsulated in the water compartment of these vesicles in order to confirm the vesicle formation. The morphology and particle size of the vesicles were characterized by an optical microscope and transmission electron microscope (TEM). The entrapment efficiencies of kojic acid and kojic oleate in the vesicles were investigated by dialysis and column chromatography, respectively. The contents of the entrapped kojic acid and kojic oleate were assayed by HPLC. The entrapment efficiency of kojic acid was 0.01-0.04 mol, whereas kojic oleate gave higher entrapment efficiency of 0.25-0.35 mol/mol of the total compositions of amphiphile/cholesterol/dicetyl phosphate. Structural modification of kojic acid improved its entrapment in the vesicles. Tween 61 vesicles could entrap kojic oleate more than did Span 60 vesicles. The pi-A isotherms revealed the lower area per molecule of Span 60, which formed a more rigid pack of its molecule on air/water interface than that of Tween 61. This implied the high rigidity of vesicular membrane prepared with Span 60 led to the lower amount of kojic oleate entrapped in the vesicles. From the release study of kojic acid through the dialysis membrane, it indicated that the intercalation of kojic oleate in the vesicular membranes did not significantly affect the release of kojic acid from the vesicles.

[Similarity between primary health care and health promotion]

Primary Health Care is recognized as a core health strategy in developing countries, proclaimed by the Declaration at Alma-Ata, while for industrialized countries, Health Promotion was stated in the Ottawa Charter. The concept of Primary Health Care, having been influenced by the Social Development movement for basic human needs in the 70s, is almost entirely consistent with Health Promotion, which is in accord with the principles of Human Development pronounced in the late 80s through the 90s. Thus, Health Promotion could be developed as a health strategy also in developing countries while Primary Health Care could similarly be adopted as a health strategy in the industrialized world.

Biochemical analysis of replication factor C from the hyperthermophilic archaeon Pyrococcus furiosus

Replication factor C (RFC) and proliferating cell nuclear antigen (PCNA) are accessory proteins essential for processive DNA synthesis in the domain Eucarya. The function of RFC is to load PCNA, a processivity factor of eukaryotic DNA polymerases delta and epsilon, onto primed DNA templates. RFC-like genes, arranged in tandem in the Pyrococcus furiosus genome, were cloned and expressed individually in Escherichia coli cells to determine their roles in DNA synthesis. The P. furiosus RFC (PfuRFC) consists of a small subunit (RFCS) and a large subunit (RFCL). Highly purified RFCS possesses an ATPase activity, which was stimulated up to twofold in the presence of both single-stranded DNA (ssDNA) and P. furiosus PCNA (PfuPCNA). The ATPase activity of PfuRFC itself was as strong as that of RFCS. However, in the presence of PfuPCNA and ssDNA, PfuRFC exhibited a 10-fold increase in ATPase activity under the same conditions. RFCL formed very large complexes by itself and had an extremely weak ATPase activity, which was not stimulated by PfuPCNA and DNA. The PfuRFC stimulated PfuPCNA-dependent DNA synthesis by both polymerase I and polymerase II from P. furiosus. We propose that PfuRFC is required for efficient loading of PfuPCNA and that the role of RFC in processive DNA synthesis is conserved in Archaea and Eucarya.

Bronchial atresia: three-dimensional CT bronchography using volume rendering technique

We report a case of asymptomatic bronchial atresia of the anterobasal and laterobasal segments of the right lower lobe. Because of the absence of typical bronchial mucocele on chest radiograph, it was difficult to base the diagnosis on chest radiography alone. Helical CT images demonstrated the characteristic appearance of bronchial atresia, and three-dimensional (3D) CT bronchography using the volume rendering technique helped us to comprehend the spatial relationship between the dilated bronchus distal to the atresia and the more proximal bronchus.

Genomic structure, chromosomal localization and identification of mutations in the xeroderma pigmentosum variant (XPV) gene

The xeroderma pigmentosum variant (XP-V) is one of the most common forms of this cancer-prone syndrome. XP groups A through G are characterized by defective nucleotide excision repair, whereas the XP-V phenotype is proficient in this pathway. The XPV gene encodes DNA polymerase eta, which catalyzes an accurate translesion synthesis, indicating that the XPV gene contributes tumor suppression in normal individuals. Here we describe the genomic structure and chromosomal localization of the XPV gene, which includes 11 exons covering the entire coding sequence, lacks a TATA sequence in the upstream region of the transcription-initiation, and is located at the chromosome band 6p21.1-6p12. Analyses of patient-derived XP-V cell lines strongly suggested that three of four cell lines carried homozygous mutations in the XPV gene. The fourth cell line, XP1RO, carried heterozygous point mutations in the XPV gene, one of which was located at the splice acceptor site of exon 2, resulting in the omission of exon 2 from the mature mRNA. These findings provide a basis for diagnosis and therapy of XP-V patients.

Molecular dimensions of Hb-based O(2) carriers determine constriction of resistance arteries and hypertension

The effect of molecular dimension of hemoglobin (Hb)-based O(2) carriers on the diameter of resistance arteries (A(0), 158 +/- 21 microm) and arterial blood pressure were studied in the conscious hamster dorsal skinfold model. Cross-linked Hb (XLHb), polyethylene glycol (PEG)-conjugated Hb, hydroxyethylstarch-conjugated XLHb, polymerized XLHb, and PEG-modified Hb vesicles (PEG-HbV) were synthesized. Their molecular diameters were 7, 22, 47, 68, and 224 nm, respectively. The bolus infusion of 7 ml/kg of XLHb (5 g/dl) caused an immediate hypertension (+34 +/- 13 mmHg at 3 h) with a simultaneous decrease in A(0) diameter (79 +/- 8% of basal value) and a blood flow decrease throughout the microvascular network. The diameter of smaller arterioles did not change significantly. Infusion of larger O(2) carriers resulted in lesser vasoconstriction and hypertension, with PEG-HbV showing the smallest changes. Constriction of resistance arteries was found to be correlated with the level of hypertension, and the responses were proportional to the molecular dimensions of the O(2) carriers. The underlying mechanism is not evident from these experiments; however, it is likely that the effects are related to the diffusion properties of the different Hb molecules.

Synthesis and physicochemical characterization of a series of hemoglobin-based oxygen carriers: objective comparison between cellular and acellular types

A series of hemoglobin (Hb)-based O(2) carriers, acellular and cellular types, were synthesized and their physicochemical characteristics were compared. The acellular type includes intramolecularly cross-linked Hb (XLHb), polyoxyethylene (POE)-conjugated pyridoxalated Hb (POE-PLP-Hb), hydroxyethylstarch-conjugated Hb (HES-XLHb), and glutaraldehyde-polymerized XLHb (Poly-XLHb). The cellular type is Hb-vesicles (HbV) of which the surface is modified with POE (POE-HbV). Their particle diameters are 7 +/- 2, 22 +/- 2, 47 +/- 17, 68 +/- 24, and 224 +/- 76 nm, respectively, thus all the materials penetrate across membrane filters with 0.4 microm pore size, though only the POE-HbV cannot penetrate across the filter with 0.2 microm pore size. These characteristics of permeability are important to consider an optimal particle size in microcirculation in vivo. POE-PLP-Hb ([Hb] = 5 g/dL) showed viscosity of 6.1 cP at 332 s(-1) and colloid osmotic pressure (COP) of 70.2 Torr, which are beyond the physiological conditions (human blood, viscosity = 3-4 cP, COP = ca. 25 Torr). XLHb and Poly-XLHb showed viscosities of 1.0 and 1.5 cp, respectively, which are significantly lower than that of blood. COP of POE-HbV is regulated to 20 Torr in 5% human serum albumin (HSA). HES-XLHb and POE-HbV/HSA showed comparable viscosity with human blood. Microscopic observation of human red blood cells (RBC) after mixing blood with POE-PLP-Hb or HES-XLHb disclosed aggregates of RBC, a kind of sludge, indicating a strong interaction with RBC, which is anticipated to modify peripheral blood flow in vivo. On the other hand, XLHb and POE-HbV showed no rouleaux or aggregates of RBC. The acellular Hbs (P(50) = 14-32 Torr) have their specific O(2) affinities determined by their structures, while that of the cellular POE-HbV is regulated by coencapsulating an appropriate amount of an allosteric effector (e.g., P(50) = 18, 32 Torr). These differences in physicochemical characteristics between the acellular and cellular types indicate the advantages of the cellular type from the physiological points of view.

[Table-moving contrast-enhanced MR angiography of abdominal aortic aneurysm]

Table-moving contrast-enhanced MR angiography (MRA) was performed in 14 cases of abdominal aortic aneurysm to evaluate its clinical usefulness. In all cases, aneurysms were clearly demonstrated and image quality was clinically acceptable. Findings of reconstructed MRA were highly consistent with those of DSA, and thrombosed areas were confirmed on source images. Main aortic branches including renal arteries, common iliac arteries, and internal and external iliac arteries were readily identified on reconstructed MRA and/or source images. Additional findings such as thoracic aortic aneurysm (n = 1), common iliac aneurysm (n = 6), external iliac aneurysm (n = 1), internal iliac aneurysm (n = 1), femoral arterial obstruction (n = 2), and femoral arterial stenosis (n = 4) were also detected. Although table-moving MRA may have disadvantages like reduced blood signal and limited spatial resolution compared with the conventional contrast-enhanced technique, the images that were obtained provided sufficient contrast and resolution for preoperative evaluation. Because abdominal aortic aneurysm is accompanied by various arterial abnormalities in many of the large arteries, table-moving MRA was considered a suitable technique for comprehensive assessment.

Iron depletion prevents adenine nucleotide decomposition and an increase of xanthine oxidase activity in the liver of the Long Evans Cinnamon (LEC) rat, an animal model of Wilson's disease

The Long Evans Cinnamon (LEC) rat, which accumulates excess Cu in the liver as in patients with Wilson's disease, is a mutant strain displaying spontaneous hepatitis. It was reported that Fe, like Cu, increases in the liver and that the severity of hepatitis is modified by Fe in the diet. In this experiment, oxidative stress increased by Fe was investigated before the onset of hepatitis. To examine the effect of Fe on the progress into hepatitis, LEC female rats were fed an Fe-regular (Fe 214 microg/g; Fe(+) group) or an Fe-restricted (Fe 14 microg/g; Fe(-) group) diet from 53 days of age for 35 days. Fischer rats were also fed as control animals. Adenine nucleotide decomposition was determined as an index of oxidative stress based on xanthine oxidase activity. The size of the hepatic pool of adenine nucleotides (ATP+ADP+AMP) was significantly smaller in LEC rats than Fischer rats. The energy charge (ATP+0.5ADP)/(ATP+ADP+AMP) was smaller in Fe(+) groups than in Fe(-) groups. In the LEC rat liver, the Fe concentration in the Fe(+) group was 160% of that in Fe(-) group and the correlation coefficient between the hepatic Fe concentration and the energy charge was significant. In this strain, an increase of xanthine oxidase activity resulted in an increase of xanthine, an oxidized metabolite of hypoxanthine in the liver. The results suggest the involvement of the Fe in the progression into hepatitis in the LEC rat, even if the dietary Fe concentration is similar to that of commercial diet.

Synthesis and pharmacological activity of pyrazolopyrrolopyrimidine derivatives having vasorelaxing activity

A new series of 5-substituted and 5-nonsubstituted pyrazolopyrrolopyrimidine derivatives were synthesized, and their vasorelaxing and hypotensive activities were evaluated. The syntheses were efficiently accomplished through the use of three key intermediates (7, 16, and 24), as shown in Schemes I-III. The desired pharmacological activities were confirmed on the basis of vasorelaxing activity in rat aorta (in vitro) and hypotensive activity in rats (in vivo). Specifically, compound 25 exhibited the strongest activity and appears to be a promising clinical lead for the development of a new antihypertensive agent.

The XPV (xeroderma pigmentosum variant) gene encodes human DNA polymerase eta

Xeroderma pigmentosum variant (XP-V) is an inherited disorder which is associated with increased incidence of sunlight-induced skin cancers. Unlike other xeroderma pigmentosum cells (belonging to groups XP-A to XP-G), XP-V cells carry out normal nucleotide-excision repair processes but are defective in their replication of ultraviolet-damaged DNA. It has been suspected for some time that the XPV gene encodes a protein that is involved in trans-lesion DNA synthesis, but the gene product has never been isolated. Using an improved cell-free assay for trans-lesion DNA synthesis, we have recently isolated a DNA polymerase from HeLa cells that continues replication on damaged DNA by bypassing ultraviolet-induced thymine dimers in XP-V cell extracts. Here we show that this polymerase is a human homologue of the yeast Rad30 protein, recently identified as DNA polymerase eta. This polymerase and yeast Rad30 are members of a family of damage-bypass replication proteins which comprises the Escherichia coli proteins UmuC and DinB and the yeast Rev1 protein. We found that all XP-V cells examined carry mutations in their DNA polymerase eta gene. Recombinant human DNA polymerase eta corrects the inability of XP-V cell extracts to carry out DNA replication by bypassing thymine dimers on damaged DNA. Together, these results indicate that DNA polymerase eta could be the XPV gene product.

Possible causes of diabetes mellitus in cattle infected with bovine viral diarrhoea virus

In cattle, we encountered insulin-dependent diabetes mellitus (IDDM) associated with bovine viral diarrhoea virus (BVDV) infection. To estimate the correlation between IDDM and BVDV infection, the distribution of BVDV in the pancreas and islet-cell antibody (ICA) were investigated. The distribution of BVDV in the pancreas was examined by in situ hybridization using two oligonucleotide probes that recognized the gp25- and p14-coding regions of the BVDV gene. ICA was examined by indirect fluorescence antibody assay using the sera from affected cattle and pancreata from normal cattle. In the pancreata of all BVDV-infected cattle, including IDDM-complicated cattle, oligonucleotide probe hybridized portions were recognized. In short, BVDV genes were detected not only in IDDM-complicated cattle but also in uncomplicated cattle. Moreover, there was no hybridized portion in the islet cells. In BVDV-infected and IDDM-complicated cattle, ICA was frequently detected. On the other hand, ICA was not detected in BVDV-infected and IDDM uncomplicated cattle. These results suggest that IDDM associated with BVDV infection is not a direct effect of BVDV on islet cells. Therefore, as BVDV did not induce IDDM in any cases, it appears that BVDV does not induce IDDM directly, but rather may be an autoimmune disease induced by autoantibodies against islet cells.

Automated synthesis of [11C]choline, a positron-emitting tracer for tumor imaging

(beta-Hydroxyethyl)tri([11C]methyl)ammonium ([11C]choline) is a tracer very effective in imaging various human tumors using positron emission tomography (PET). We have constructed a computer-controlled [11C]choline synthetic apparatus which carries out the whole process of synthesis and product purification automatically. The setup is simple and the process quick. In 20 min, 11 GBq of [11C]choline (chloride) is obtainable from 26 GBq of [11C]CO2. The final product is a sterile and pyrogen-free [11C]choline "injection".

Activation of extracellular signal-regulated kinase in lung tissues of mice treated with carcinogen

The activation of extracellular signal-regulated kinase (ERK) in lung tissues of mice, as determined by the appearance of phosphorylated form, was observed on day 30 after urethane injection, and the activation also occurred in urethane-induced lung tumors. Immunohistochemical analysis using anti-phosphorylated ERK antibody indicated that the active form of ERK localized in alveolar epithelial cells. Furthermore, we confirmed by immunoprecipitation and immunoblot analysis that other essential components of the ERK cascade, that is, Ras, Raf and MEK (known as ERK kinase) were activated. These results indicate that the activation of the ERK signal in alveolar epithelial cells at the early stage of urethane-induced lung carcinogenesis is an important factor to develop lung tumors.

A kuroko-type polymetallic sulfide deposit in a submarine silicic caldera

Manned submersible studies have delineated a large and actively growing Kuroko-type volcanogenic massive sulfide deposit 400 kilometers south of Tokyo in Myojin Knoll submarine caldera. The sulfide body is located on the caldera floor at a depth of 1210 to 1360 meters, has an area of 400 by 400 by 30 meters, and is notably rich in gold and silver. The discovery of a large Kuroko-type polymetallic sulfide deposit in this arc-front caldera raises the possibility that the numerous unexplored submarine silicic calderas elsewhere might have similar deposits.

The repetitive activation of extracellular signal-regulated kinase is required for renal regeneration in rat

In this study, we investigated the activation of p42 extracellular signal-regulated kinase (ERK2) during renal regeneration after HgCl2-induced acute renal failure (ARF) in rat. ERK2 activation was observed at 5 and 29 hr after HgCl2 injection, respectively. The tyrosine phosphorylation of hepatocyte growth factor receptor (c-MET) occurred between 2.5 and 5 hr after the treatment. On the other hand, the phosphorylation of epidermal growth factor receptor (EGFR) was transiently observed at 29 hr after the injection. The peak of ornithine decarboxylase activity as a marker of G1 phase was at 10 hr, and subsequently the labeling index of proliferating cell nuclear antigen as a marker of S phase increased at 53 hr. These results indicate that the repetitive activation of ERK2 related to the phosphorylation of c-MET and EGFR is required for the renal regeneration in HgCl2-induced ARF of rat.

[Detection of recurrent rectal cancer using helical CT with SmartPrep: a new technique for obtaining optimal contrast enhancement]

Seven patients with suspected recurrent rectal cancer underwent Helical CT using SmartPrep. SmartPrep is a software application developed by GE in which the ROI is placed at the desired level of the aorta prior to contrast injection. Using a low-dose continuous scan, the time density curve was obtained instantly, and the optimal timing of scanning was judged from the curve. Four patients who demonstrated intense enhancement at the anastomotic site had local recurrence. No intense enhancement was observed in these areas on conventional delayed CT. Thus, SmartPrep appears to be useful for the accurate diagnosis of recurrent rectal cancer.

Effects of oral hyposensitization with recombinant Der f2 on immediate airway constriction in a murine allergic model

Recombinant Der f2 (rDer f2) has recently been developed as a promising allergen for the diagnosis and immunotherapy of house-dust mite allergy, and studies in immunology. The aim of the present study was to evaluate whether oral administration of rDer f2 could suppress an immediate allergic reaction in mice sensitized with mite allergen. We developed a murine allergic model that showed bronchoconstriction after inhalation of rDer f2, and studied the effect of oral administration of rDer f2 on the reaction. Seven week old male A/J mice were intranasally immunized with rDer f2 12 times. Sensitized mice showed anti-rDer f2 immunoglobulin (Ig)E production and immediate airway constriction after inhalation of 10 mg.mL(-1) of rDer f2, as determined by the Konzett-Rössler method. Immunized animals were divided into three groups, and fed phosphate-buffered saline (PBS), 0.1 mg.day(-1), or 1 mg.day(-1) of rDer f2 for 4 weeks, respectively. Seven days after the last feeding, the mice were examined for their immediate response. Animals fed with 1 mg.day(-1) rDer f2 showed significantly reduced bronchoconstriction after inhalation of both 2 mg.mL(-1) and 10 mg.mL(-1) of rDer f2 compared with PBS-fed mice. Similar results were obtained when we examined mice 10 weeks after the last feeding. Reactions in the 0.1 mg.day(-1) rDer f2-fed group also tended to decrease in comparison with PBS-fed animals. Plasma anti-rDer f2 IgE, IgG1, IgG2a, and IgG2b levels were not changed by feeding with rDer f2. We conclude that recombinant Der f2 exhibits both sensitizing and hyposensitizing activities in mice. rDer f2 may be useful in immunotherapy and diagnosis of house-dust mite allergy.

[Fluorine-18 labeled 6-fluoro-L-dopa: systematization and evaluation of its usefulness]

6-[18F]Fluoro-L-dopa (L-3,4-dihydroxy-6-[18F]fluorophenylalanine; 6-[18F]FDPA) is useful to assess presynaptic dopamine metabolism in central nervous system. In this paper, we report on the usefulness of the 6-[18F]FDOPA synthesis system developed for the routine synthesis. This system consists of the 6-[18F]FOPA synthesis and the separation units in conjunction with controller using a personal computer. The synthesis time of 6-[18F]FDOPA was 73 minutes. The typical yield and specific activity were 1.4-2.4 GBq and 244-270 MBq/mumol at the end of synthesis, respectively, under the irradiation condition of 50 microA for 130 minutes. The radiochemical yields of 6-[18F]FDOPA were 31.3-38.7% based on the [18F]acetylhypofluorite, and the results were affected with the condition of potassium acetate (AcOK) to produce gaseous [18F]acetylhypofluorite. This system is useful for the routine production of 6-[18F]FDOPA because of its high yield and high specific activity while maintaining AcOK in good condition, and decreasing the radiation exposure for chemist.

The inhibitory effect of vitamin E on K-ras mutation at an early stage of lung carcinogenesis in mice

In this study, we investigated the effect of vitamin E on the activation of the K-ras oncogene with a 61st codon A-->T mutation at an early stage of urethane-induced lung carcinogenesis in mice. Thirty days after urethane injection, the K-ras mutation was detected in 64% of lung samples tested by mutant-allele-specific amplification. The consumption of a supplemented diet with about 20-times more vitamin E than the control diet, only during the promotion phase or during both the initiation and promotion phases of lung carcinogenesis, reduced the frequency of the mutation to 36 and 18%, respectively. Also, vitamin E suppressed the level of proliferating cell nuclear antigen as a marker of cell proliferation in the lungs of mice treated with urethane. These results support the notion that vitamin E is a useful chemopreventive agent against lung cancer.

[Clinical studies for venogenic impotence with color Doppler ultrasonography--evaluation of resistance index of the cavernous artery]

BACKGROUND

Pharmaco-dynamic infusion cavernosometry and cavernosography (pharmaco-DICC) is essential for diagnosis of venogenic impotence, however it is so invasive. On the other hand, color Doppler ultrasonography is non-invasive and has become one of the useful diagnostic methods for arteriogenic impotence. And there are some reports evaluating whether venogenic impotence can be diagnosed using color Doppler ultrasonography. In this study, we investigated whether the resistance index (RI) could be useful for screening for venogenic impotence.

METHODS

We performed color Doppler ultrasonography in 49 patients who had shown negative responses to an intracavernous injection of 20 mcg of prostaglandin E1 (PGE1). They previously underwent pharmaco-DICC and were diagnosed venogenic impotent when the maintenance flow rate was equal to or more than 20 ml/min. In 49 patients, 17 patients had DICC normality, while 32 patients had corporal leakages. After an intracavernous injection of 20 mcg of PGE1, we performed color Doppler ultrasonography, and measured peak systolic velocity (PSV) and end diastolic velocity (EDV) in the cavernous artery. RI was calculated as follows. RI = (PSV-EDV)/PSV We adopted the RI value near to 1 as the case's RI from two RI values of bilateral cavernous arteries, and compared RI values with the results of pharmaco-DICC.

RESULTS

RI range in patients with normal DICC results was 0.895 +/- 0.092 (0.70-1.00), while RI range in patients with corporal leakages was 0.742 +/- 0.095 (0.55-0.97). RI values in patients with corporal leakages were significantly lower than those in patients with normal DICC results although there was some overlap in each group. From receiver-operating-characteristic curve (ROC curve) of the correlation between sensitivity and specificity at various RI values compared with DICC results, the RI cut off values were set up at 0.75 and 0.90, and classified the patients into 3 group according to their RI cut off values. In 10 patients with 0.9 < RI, 9 patients (90%) had DICC normality. In 17 patients with 0.75 < RI < or = 0.9, 7 patients had DICC normality while 10 patients had corporal leakages. In 22 patients with RI < or = 0.75, 21 patients (95.5%) had corporal leakages.

CONCLUSION

We consider without carrying out pharmaco-DICC that patients with 0.9 < RI were not venogenic impotent, while patients with RI < or = 0.75 had corporal leakages. Pharmaco-DICC will remain essential only in patients with 0.75 < RI < or = 0.9.

Biliary excretion of copper, manganese, and horseradish peroxidase in Eisai hyperbilirubinemic mutant rats (EHBRs) with defective biliary excretion of glutathione

A mixture of copper (Cu) (0.38 mg/kg), manganese (Mn (0.038 mg/kg), and horseradish peroxidase (HRP) (5.0 mg/kg) was injected intravenously (i.v.) into mature Eisai hyperbilirubinemic rats (EHBRs) and Sprague-Dawley rats (SDRs). Bile was collected at 10-min intervals before and after the injection, under anesthesia. The liver, kidneys, and blood were removed 40 min after the injection. The serum conjugated bilirubin concentration was 0.85 mg/dL in the EHBRs, but was below detection limits in the SDRs. The bile-reduced glutathione (GSH) concentration was much lower in the EHBRs (0.04 mg/mL) than in the SDRs (1.30 mg/mL). However, the hepatic GSH concentration was about 1.6 times higher in EHBRs (2.26 mg/g liver) than in SDRs (1.43 mg/g liver). The low excretion of biliary GSH was not caused by the activity of GGT in the liver, since there was no significant difference in the activity between the two groups (5.8 +/- 3.4 and 4.6 +/- 2.4 mumol p-nitroaniline/g protein/30 min in SDR and EHBR groups, respectively). There was a delay of initial biliary excretion of Cu in EHBRs compared to SDRs. The biliary concentration of Mn was slightly lower in EHBRs than in SDRs. Forty min after the injection of metals, however, there was no difference between hepatic concentrations of the two metals in the two groups. Our results suggest that abnormal deposition of the two metals is not observed naturally in EHBRs. Injected HRP was excreted rapidly and notably in the EHBRs compared to SDRs. Furthermore, the biliary concentration of beta-N-acetyl-D-glucosaminidase (beta-NAG) was significantly higher in EHBRs than in SDRs, Rapid biliary excretion of Cu, but not of Mn, may be related to the hepatobiliary transport of GSH, but the transport and lysosomal function do not originally regulate the biliary excretion of Cu.

Non-decay type fast-setting calcium phosphate cement: setting behaviour in calf serum and its tissue response

Non-decay type fast-setting calcium phosphate cement (nd-FSCPC) was evaluated in terms of its setting behaviour in calf serum and its tissue response to investigate the feasibility of its clinical use in surgical applications. Non-decay type cements were prepared by adding various amounts of sodium alginate to the liquid phase of base cements, fast-setting calcium phosphate cement (FSCPC) and conventional calcium phosphate cement (c-CPC). Cement pastes were immersed in serum at 37 degrees C immediately after mixing, and decay behaviour, setting time and mechanical strength were measured to evaluate the possibility of their use in surgical applications. Also, nd-FSCPC was implanted into rat subcutaneous tissue for the initial evaluation of biocompatibility of this potential bioactive cement. nd-FSCPC set in approximately 6-7 min in serum, even when the cement paste was immersed in the serum immediately after mixing, whereas c-CPC and FSCPC decayed completely upon immersion. nd-FSCPC transforms to hydroxyapatite (HA) within 24 h and shows a diametral tensile strength of approximately 4-5 MPa. As a result of transformation to HA, nd-FSCPC showed excellent tissue response when implanted subcutaneously in rats. We conclude that nd-FSCPC has good potential value for use in orthopaedics, plastic and reconstructive surgery, and oral and maxillofacial surgery, where the cement is exposed to blood.

[A study of coping in middle-aged women with urinary incontinence]

The purpose of this study is to clarify the coping patterns of women with urinary incontinence (UI) who visited an incontinence special unit. Nineteen patients ranging from 42 to 86 in age were interviewed. When they had met the accidents or daily occurrences with UI, their attitudes toward UI were classified into six coping patterns. They were "managing of UI", "keeping UI in secret", "asking for medical treatment for UI", "asking for support", "accepting UI as a fact or being resigned to UI, and "avoiding the fact with UI". All these six coping patterns reflect their desire to keep themselves in normal status. They concentrated themselves on maintain the normalization so as to keep their self-esteem from the threat of UI.

[New nocturnal penile tumescence recorder]

BACKGROUND

Records of nocturnal penile tumescence are still important test and necessary to distinguish organic impotence from psycogenic impotence.

METHODS

We developed the nocturnal penile tumescence recorder with a disposab indiumgallium straingauge, and we examined its clinical usefulness for volunteers with normal erectile function.

RESULTS

The results were that the indium-gallium straingauge had almost the same resistance change with extension, and that it showed almost the same resistance value at respective circumferences with consecutively ten times measurements. Only two of thirty-nine volunteers experienced the snapping of the indium-gallium strain-gauge. None of the volunteers complained of discomfort during measurements. The nocturnal penile tumescence of five volunteers were recorded with a conventional mercuric straingauge and a newly developed indium-gallium straingauge simultaneously, and there were no significant differences between the results of the two materials. This recorder is very simple to manage, and the softwares for preservation of data and making graph are also simple. This new straingauge is clean and dose not require maintenance because of the disposable use.

CONCLUSION

We concluded that this recorder system was clinically useful for t examination of nocturnal penile tumescence.