Depositional records of plutonium and (137)Cs released from Nagasaki atomic bomb in sediment of Nishiyama reservoir at Nagasaki

In a sediment core of Nishiyama reservoir at Nagasaki city, depth profiles of (240)Pu/(239)Pu isotopic ratio, (239+240)Pu and (137)Cs activities were determined. Sediments containing plutonium and (137)Cs, which were deposited immediately after a detonation of Nagasaki atomic bomb, were identified in the core. Observed below the sediments were macroscopic charcoals, providing evidence for initial deposit of the fallout of the Nagasaki atomic bomb. This is the first entire depositional records of plutonium and (137)Cs released from the Nagasaki atomic bomb together with those from atmospheric nuclear tests.

Expression and activity of matrix metalloproteinase 2 and 9 in human trophoblasts

Indiscriminate invasion upon the endometrium by normal trophoblasts is strictly regulated unlike that by choriocarcinoma cells. In this study, we focused on the activity of matrix metalloproteinase (MMP)-2 and MMP-9 as parameters of invasion in normal human placenta. In situ hybridization (ISH), immunohistochemical staining (IH) and film in situ zymography (FIZ) were performed to identify cells having MMP-2 or MMP-9 expression and activity. Purified cytotrophoblasts (CTs) were used to examine the expression and activity of MMP-2 and MMP-9, and their invasive ability. In first trimester placental tissue, the MMP-2 expression was observed in extravillous trophoblasts (EVTs), and MMP-9 mainly in villous cytotrophoblasts (VCTs). FIZ revealed marked gelatinase activity in the EVTs which MMP-2 expression was observed in. In full-term placental tissue, the MMP-2 expressions was observed in the EVTs similar to that in first trimester, whereas the gelatinase activity in these cells was decreased or completely lost. Using purified CTs, the gelatinase activity was marked in early CTs, but not term CTs. Invasive ability of early CTs was inhibited by tissue inhibitor of metalloproteinase (TIMP)-2 and MMP-2 antibody in a dose dependent manner. These suggests that the invasive ability of trophoblasts may be regulated by the enzyme activity of gelatinases, especially MMP-2.

Determination of hepatitis B virus genotype G by polymerase chain reaction with hemi-nested primers

Hepatitis B virus (HBV) has been classified into six genotypes designated A-F by sequence divergence in the entire genome exceeding 8%. Very recently, the seventh genotype was reported and named genotype G. HBV genotype G is distinct from genomes of the other six genotypes in that it possesses an insertion of 36 nucleotides in the core gene, and has been found so far in France and the United States. A method for determining HBV genotype G was developed by polymerase chain reaction (PCR) with primers deduced from the 36-nucleotide (nt) insertion in five isolates of HBV genotype G the sequences of which have been deposited in DNA databases. The validity of this method, for specifically detecting HBV genotype G, was verified on a panel consisting of 142 HBV isolates of six major genotypes and four of genotype G. A total of 540 sera containing HBV in Japan covering symptom free carriers and patients with a spectrum of chronic liver disease were tested by this method, but not a single HBV genotype G sample was found. A possible method for serological determination of hepatitis B surface antigen of genotype G is suggested, without amplification or sequencing nucleotides, which would expand epidemiological and clinical researches on HBV genotype G.

Pharmacological effect of tamsulosin in relation to dog plasma and tissue concentrations: prostatic and urethral retention possibly contributes to uroselectivity of tamsulosin

In the present study the pharmacokinetics and pharmacodynamics of tamsulosin were investigated in anesthetized male dogs. Hypogastric nerve stimulation elevated the intraurethral pressure (IUP), which was inhibited dose dependently by intraduodenal administration of tamsulosin (3-30 microg/kg). The inhibition peaked about 90 min after dosing and lasted up to 240 min. The basal mean blood pressure did not change significantly during the observation period. The plasma, prostatic, and urethral concentrations of tamsulosin were determined by the liquid chromatography-mass spectrometry/mass spectrometry method. The plasma concentration reached the maximal level within 30 min after dosing and gradually declined thereafter. The maximal total plasma concentration of tamsulosin (C(max, t)) and its unbound concentration (C(max, u)) correlated with the maximal effect on IUP response [r(2) = 0.81 (p<0.01, n = 15) and r(2) = 0.84 (p<0.01, n = 15), respectively]. Each individual unbound plasma concentration did not correlate, however, with its associated inhibition of IUP response (r(2) = 0.04, n = 126). Although the plasma concentration of tamsulosin decreased nearly to the lower limit of quantitation 240 min after dosing, the prostatic and urethral concentrations remained high, i.e., 13 to 44 times greater than the plasma concentration. Our data demonstrate that the maximal inhibition by tamsulosin of IUP response is well correlated with the maximal plasma concentration in the early phase. The sustained effect of tamsulosin on IUP response that follows may be related to prostatic and urethral retention of tamsulosin.

Chemical analysis of transuranium nuclides in the uranium solution of the JCO criticality accident

Atom numbers of 239Np and 239Pu, which had been produced by the neutron capture reaction of 238U in the uranium solution of the JCO criticality accident at Tokai-mura, Japan, were determined precisely by a radiochemical method. It was found that the measured atom ratio of 239Np/239Pu at termination of the criticality depends sensitively on the history of the neutron capture reaction during the accident (about 20-hours continuance). The history was evaluated by comparing the measured value and those calculated by a burnup calculation code. The percentage of the number of the neutron capture reaction at the initial stage of the criticality during 25 min against the total events was determined to be 24±6%.

Ventricular function and cardiac hypertrophy after coronary thrombolysis with tissue-type plasminogen activator (t-PA) in dogs with coronary artery thrombi

Subacute prognosis of cardiac function after thrombolysis with a modified tissue-type plasminogen activator (t-PA) YM866 was determined in dogs with coronary artery thromboses induced by injection of a thrombin, fibrinogen and autogenous blood mixture. The left ventricular ejection fraction (LVEF) decreased 30 min after occlusion and had not improved 1 week later. Examination after sacrifice revealed myocardial infarction as well as increases in both the left ventricular myocardial area and heart mass. Occluded coronary arteries reperfused by YM866 (0.1 mg kg(-1) i.v.) treatment 30 min after occlusion, by contrast, had improved LVEF and inhibited myocardial infarction development. In addition, the left ventricular myocardial area and heart mass were significantly reduced compared with the vehicle control group 1 week after administration. Although occluded coronary arteries reperfused by YM866 (0.1 mg kg(-1) i.v.) treatment 3 h after occlusion did not show an improvement in the LVEF or inhibition of myocardial infarction development, the left ventricular myocardial area and heart mass decreased significantly compared with the vehicle control group 1 week after administration. In conclusion, early reperfusion by t-PA treatment 30 min after occlusion improved the ventricular function and cardiac hypertrophy, whereas late reperfusion by t-PA treatment 3 h after occlusion did not improve the ventricular function but did inhibit hypertrophy in dogs with coronary artery thrombi.

Clinical applications of serum placental protein 14 (PP14) measurement in the IVF-ET cycle

OBJECTIVE

Placental protein 14 (PP14) is known to be one of the endometrial proteins that reflect endometrial functioning throughout the menstrual cycle. In this study, we examined PP14 as a marker for human endometrial receptivity in order to predict the outcome of in vitro fertilization and the embryo-transfer (IVF-ET) cycle.

PATIENTS AND METHODS

The subjects were 72 women who had 96 IVF-ET cycles and who were examined at Tokyo Medical University Hospital during the period of January 1998 to June 1998 because of mechanical or unexplained infertility for a duration of at least 2 years. Serum samples were collected from all patients during treatment cycles, and serum PP14 concentrations were measured by a newly established enzyme-linked immunosorbent assay (ELISA).

RESULTS

In the pregnant group, serum PP14 concentrations were markedly increased after ET, and a significant difference between the pregnant group and the nonpregnant group was observed 8 days following ET (p < 0.01). PP14 concentrations were higher in patients with endometria that exhibited homogenous patterns and that were more than 7 mm thicker than in other patients, as determined by ultrasound on the day of oocyte collection (p < 0.005). The pregnancy rates of patients with homogeneous patterns were lower than those of patients showing a trilaminar pattern. No pregnancies were observed when serum PP14 concentrations were greater than 6.85 U/l on the day of oocyte collection.

CONCLUSION

PP14 might be a useful marker for human endometrial receptivity to predict the outcome of IVF-ET cycles.

Development of analytical techniques for ultra trace amounts of nuclear materials in environmental samples using ICP-MS for safeguards

The authors have begun to develop analytical techniques for ultra trace amounts of nuclear materials and to prepare a clean chemistry laboratory for environmental sample analyses. The analytical techniques include bulk and particle analyses. For the bulk analysis, concentrations and isotopic ratios of U and/or Pu are determined by inductively-coupled plasma mass spectrometry (ICP-MS) and thermal ionization mass spectrometry (TIMS). In the particle analysis, isotopic ratios of U and/or Pu in each particle will be measured by secondary ion mass spectrometry (SIMS). This paper reports on the outline for the development of analytical techniques and the current situation of the development of the bulk analysis using ICP-MS is described.

Thrombopoietic activity of recombinant human interleukin-11 in nonhuman primates with ACNU-induced thrombocytopenia

The effect of recombinant human interleukin-11 (rHuIL-11) on myelosuppressive nimustine (ACNU)-induced thrombocytopenia was assessed in nonhuman primates. A single intravenous (i.v.) injection of ACNU (15 mg/kg) was administered to cynomolgus monkeys on day 0. rHuIL-11 (100 microg/kg/day) or the vehicle was given subcutaneously (s.c.) from day 1 to day 21. In monkeys receiving ACNU, the circulating platelet count decreased to a low of 42 +/- 6 x 10(9)/L by day 21 but returned to pretreatment levels (375 +/- 48 x 10(9)/L) on day 30. Administration of rHuIL-11 prevented severe thrombocytopenia; the platelet count fell only to 138 +/- 23 x 10(9)/L on day 18, and platelet recovery was faster (458 +/- 91 x 10(9)/L by day 27) compared with that of the control animals. The size of bone marrow megakaryocytes from rHuIL-11-treated animals was larger than that of the controls, indicating that rHuIL-11 stimulated megakaryopoiesis in a myelosuppressive condition. Treatment with ACNU also caused leukopenia and moderate anemia. rHuIL-11 transiently and slightly decreased the white blood cell (WBC) and red blood cell (RBC) counts. Conversely, rHuIL-11 accelerated recovery of RBC count in the late administration period. These results support the assertion that rHuIL-11 may be an important therapeutic agent for reducing the severity and duration of thrombocytopenia following cancer chemotherapy.

Differentiation of hepatitis B virus genotypes D and E by ELISA using monoclonal antibodies to epitopes on the preS2-region product

An enzyme-linked immunosorbent assay (ELISA) has been described for serological determination of hepatitis B virus genotypes, using monoclonal antibodies (mAb) against seven distinct epitopes (b, m, k, s, u, f and g) on the preS2-region products of hepatitis B surface antigen (HBsAg). The usefulness of this method for serological detection of genotype E, however, was theoretical, because no HBsAg samples of this genotype were included in the original test panel. Moreover, the predicted serotype of genotype E (bksufg) closely resembled that of genotype D (bksu, bksuf or bksug). Four HBsAg samples of genotype E were tested by the original described ELISA. The epitope g, predicted to be present in these samples by amino acid sequences, was not detected when HBsAg of genotype E was captured on a solid phase by mAb to the common determinant 'a' of HBsAg and then reacted with mAb to g (5156) labeled with horseradish peroxidase. However, the four examples of HBsAg of genotype E were captured by mAb 5156 to g on a solid phase; they were then detected by labeled mAb to the common determinant 'a'. Since epitopes f and g co-occurred on HBsAg of genotype E, HBsAg samples of this genotype were also detected, by 'sandwiching' them between immobilized mAb to g and labeled mAb to f. By contrast, HBsAg of genotype D in 90 sera was not reactive when sandwiched between mAb to f and g. Thus, this modified ELISA enables the serological determination of all six genotypes of HBsAg and, by inference, of hepatitis B virus.

Properties of a YAP powder scintillator as alpha-ray detector

A YAP scintillator (YAlO3: Ce crystal) for alpha counting has been produced in powder form and this paper describes its performance characteristics. By measuring pulse-height and rise-time distributions, it was found that the YAP powder, as a fast detector for alpha rays, could clearly distinguish alpha events from beta and gamma events. In addition, the YAP powder was used in a phoswich detector combined with a YAG (Y3Al5O12: Ce) crystal for beta and gamma detection.

Full-genome sequence analyses of hepatitis B virus (HBV) strains recovered from chimpanzees infected in the wild: implications for an origin of HBV

Hepatitis B virus (HBV) belongs to the genus Orthohepadnavirus of the family Hepadnaviridae. Having been found in various animals (duck, heron, woodchuck, ground squirrel, and primates), hepadnaviruses must have undergone a long history of evolution and may comprise more members than currently recognized. Chimpanzees may also have their own hepadnavirus, even if it might be very close to HBV. We analyzed HBV-like sequences from three chimpanzees (Pan troglodytes) that were most likely infected during their life in Africa in the wild. Two chimpanzees (Ch256 and Ch258) possessed a viral genome of 3182 nt in length with a 33-nt deletion in the preS1 region, which could not be classified into any of the six genotypes (A-F) of human HBV but was very homologous to a previously reported isolate from a London Zoo chimpanzee. Phylogenetically distinct from the HBV-like sequences from gibbons, orangutans, and a gorilla so far reported, the Ch256 and Ch258 isolates would represent an indigenous chimpanzee HBV (tentatively ChHBV). A third chimpanzee (Ch195) had a 3212-nt genome, classifiable into the genotype E of HBV. Because HBV-E has been found mostly in Africans, Ch195 may have been infected from a human source in Africa. However, an inverse scenario is also possible: a spread of HBV-E might have occurred from chimpanzees to humans a long time ago in Africa. Analysis of the arginine-rich C-terminal region of the core protein, which is well conserved among mammalian hepadnaviruses, indicated that HBV-E/F and nonhuman primate hepadnaviruses are much closer than HBV-A/B/C/D to the hepadnaviruses of woodchuck and ground squirrel. Our results support an "ex-nonhuman primate" hypothesis for the origin of HBV.

Mutation and transcription analyses of the p63 gene in cervical carcinoma

Genetic mutation of p53, which monitors DNA damage and operates cellular checkpoints, is a major factor in the development of human malignancies. A novel gene p63/p73L/p51, encoding a protein with significant homology to p53 and p73, was recently identified at 3q27-9. To investigate the penetration of p63 in cervical carcinogenesis, mutation and transcription analyses of p63 were performed in cervical carcinoma. A certain isotype of p63 called TAp63gamma encodes the acidic N-terminus and possesses a short C-terminus. Using reverse transcriptase-polymerase chain reaction-single strand conformation polymorphism (RT-PCR-SSCP) analysis for TAp63gamma, one mutation was found in the cervical carcinoma cell line SKG-I. However, no mutations causing amino acid substitutions or frameshifts were found in 54 cases examined for TAp63gamma, which is thought to be a tumor suppressor gene. While cervical carcinomas tended to yield a positive signal in the RT-PCR reaction designed to amplify transcripts encoding the acidic N-terminus, normal cervix and cervical intraepithelial neoplasia (CIN) did not express this transcript. These data suggest that the p63 gene does not play an essential role as a tumor suppressor gene, but expression of TAp63gamma may be speculatively associated with tumor growth in cervical carcinogenesis.

Development and evaluation of a new canine myocardial infarction model using a closed-chest injection of thrombogenic material

A new canine myocardial infarction model using thrombi induced by closed-chest injection of thrombin and autogenous blood with fibrinogen into coronary arteries was developed. Occlusive thrombi were formed in all treated animals. Occluded vessels did not spontaneously reperfuse 1 day after occlusion, but did so within 3 days. Infarction was confirmed by increased levels of creatine kinase-MB, glutamate-oxaloacetate transaminase and a-hydroxybutyrate dehydrogenase. Additionally, the left ventricular ejection fraction (LVEF) decreased within 0.5 h after occlusion and had not improved 4 weeks later. After 1 week, extensive transmural anteroinferior myocardial infarction was observed and heart mass had increased. By 4 weeks after occlusion, pulmonary capillary wedge pressure and central venous pressure were increased, and oxygen pressure was decreased. Dropout of nuclei in cardiomyocytes and increased amount of collagen fiber were observed in myocardial infarct regions of hearts excised 4 weeks after occlusion. This canine model may be useful and convenient in evaluating treatment efficacy and the long-term outcome of acute myocardial infarction.

Serological detection of hepatitis B virus genotypes by ELISA with monoclonal antibodies to type-specific epitopes in the preS2-region product

An ELISA was developed for serological determination of the six genotypes of hepatitis B virus (HBV) designated A, B, C, D, E, and F. Monoclonal antibodies were raised against genotype-specific epitopes in the preS2-region product, and labeled with horseradish peroxidase. Hepatitis B surface antigen (HBsAg) in sera was captured by immobilized antibodies against the common determinant, and evaluated for reactivity with genotype-specific monoclonal antibodies labeled with the enzyme. Serological genotyping was in complete accord with genotypes determined by S-gene sequences in a panel of 68 sera containing HBV/HBsAg of different genotypes. Of 514 sera with HBsAg from Japan, 507 (98.6%) were genotyped serologically: genotype A was identified in 24 (4.7%); B in 196 (38.1%); C in 282 (54.9%); D in 2 (0.4%); and F in 3 (0.6%). There were no sera containing HBV of genotype E. Likewise, 425 of 446 (95.3%) sera with HBsAg from Brazil, China, India, Indonesia, Kenya, Korea, Nepal, Papua New Guinea, the Philippines, and Thailand were classified into A (25.6%), B (24.2%), C (33.9%), and D (11.7%) genotypes; there were no sera with HBsAg of genotype E or F among them. Some sera unclassifiable by ELISA revealed mixed infection with HBV of distinct genotypes, or contained HBsAg deprived of genotype-specific epitopes by point mutations. The ELISA would be useful for large-scale surveys, because it allows serological detection of HBV genotypes without sequencing nucleotides.

Antibodies against type II phospholipase A2 prevent renal injury due to ischemia and reperfusion in rats

This study was performed to determine the involvement of type II phospholipase A2 (PLA2-II) in renal injury caused by ischemia and reperfusion. Ischemia and reperfusion significantly elevated levels of blood urea nitrogen and serum creatinine in rats. These increases were significantly reduced by i.v. administration of rabbit IgG F(ab')2 fragments against rat PLA2-II. Increased levels of acid-stable PLA2 activity in the kidney were caused by ischemia and reperfusion, and were suppressed by administration of anti-PLA2-II F(ab')2. Increased levels of myeloperoxidase activity, a marker of neutrophil infiltration, in the kidney were also reduced after anti-PLA2-II F(ab')2 treatment. These results suggest that PLA2-II plays a pivotal role in pathogenesis of ischemia and reperfusion injury through induction of neutrophil infiltration.

An enzyme-linked immunosorbent assay with monoclonal antibodies for the determination of phosphorylated hepatitis B core protein (p21c) in serum

An enzyme-linked immunosorbent assay (ELISA) was developed for the determination of hepatitis B virus (HBV) core protein (p21c) using monoclonal antibody (mAb) directed to a phosphorylated C-terminal amino acid sequence that is not present in hepatitis B e antigen (HBeAg). HBV virions in the test serum were precipitated with horse polyclonal antibody to hepatitis B surface antigen (HBsAg), dissolved with Tween 20 and NaOH, and then neutralized. HBV core protein (p21c), released from HBV cores by this procedure, was sandwiched between immobilized mAb C33 directed to amino acids (aa) 133-140 of the core protein, fixed on a solid support and labeled mAb T2212 that recognizes aa 165-175, only when they are phosphorylated. The method was applied for the detection of phosphorylated p21c in sera from symptom-free carriers and patients with chronic hepatitis. The results indicated a higher extent of phosphorylation in p21c of HBV cores from symptom-free carriers than hepatitis patients.

YM866, a novel modified tissue-type plasminogen activator, affects left ventricular function and myocardial infarct development in dogs with coronary artery thrombi

YM866 is a novel modified tissue-type plasminogen activator (t-PA). Its effects on left ventricular function and myocardial infarct development in dogs with copper coil-induced coronary artery thrombosis were compared with those of a native t-PA, alteplase. YM866 (bolus injection) and alteplase (bolus plus infusion) were administered 15 min after coronary artery occlusion. YM866 and alteplase produced reperfusion in all animals, with a median time to reperfusion of 10 min. In contrast, no reperfusion occurred in the vehicle control group. Left ventricular ejection fraction (LVEF) significantly decreased 15 min after coronary occlusion. YM866 and alteplase improved LVEF 3 hr and 4 hr after administration, respectively, while LVEF did not improve in the vehicle control group. Only slight myocardial infarct areas were observed in both YM866- and alteplase-administered groups, while the area in the vehicle control group accounted for 18.2% of left ventricular myocardial area. In conclusion, although both YM866 and alteplase reperfused occluded coronary arteries, inhibited myocardial infarct development and improved LVEF in dogs with coronary artery thrombi, only a single bolus injection of YM866 was necessary to achieve these improvements. Therefore, YM866 shows promise as an improved clinical agent in treating acute myocardial infarction.

An enzyme-linked immunosorbent assay with monoclonal antibodies for the determination of phosphorylated hepatitis B core protein (p21c) in serum

An enzyme-linked immunosorbent assay (ELISA) was developed for the determination of hepatitis B virus (HBV) core protein (p21c) using monoclonal antibody (mAb) directed to a phosphorylated C-terminal amino acid sequence that is not present in hepatitis B e antigen (HBeAg). HBV virions in the test serum were precipitated with horse polyclonal antibody to hepatitis B surface antigen (HBsAg), dissolved with Tween 20 and NaOH, and then neutralized. HBV core protein (p21c), released from HBV cores by this procedure, was sandwiched between immobilized mAb C33 directed to amino acids (aa) 133-140 of the core protein, fixed on a solid support and labeled mAb T2212 that recognizes aa 165-175, only when they are phosphorylated. The method was applied for the detection of phosphorylated p21c in sera from symptom-free carriers and patients with chronic hepatitis. The results indicated a higher extent of phosphorylation in p21c of HBV cores from symptom-free carriers than hepatitis patients.

Pharmacological profile of nicardipine hydrochloride in anesthetized dogs with acute heart failure. Part 1: Hemodynamic effects in normal dogs and dogs with acute heart failure

Cardiovascular effects of nicardipine hydrochloride (NIC, CAS 54527-84-3, Perdipine), a calcium channel blocker, were investigated in anesthetized normal dogs and dogs with acute heart failure (AHF), and compared with those of nitroglycerin (NTG). In open-chest anesthetized dogs, NIC (0.1-10 micrograms/kg/min i.v.) dose-dependently increased cardiac output (CO) and coronary blood flow as well as decreased mean blood pressure (MBP). NIC had no effect on heart rate (HR) or maximum rate of rise of left ventricular pressure (max. dp/dt). In contrast (0.1-10 micrograms/kg/min i.v.) decreased MBP, but did not change the other cardiovascular parameters. NIC and NTG did not prolong PQ, QRS or QTc intervals. In addition, NIC was effective in the presence of dobutamine. In the anesthetized dog model of ischemic AHF induced by coronary ligation, and ischemia/angiotensin II-induced AHF, NIC (1 and 3 micrograms/kg/min i.v.) increased CO and stroke volume, and reduced total peripheral resistance without decreasing HR or cardiac contractility. Furthermore, in the ischemia/angiotension II-induced AHF model, NIC decreased left ventricular end-diastolic pressure (LVEDP). In contrast, NTG (1-10 micrograms/kg/min i.v.) decreased LVEDP in both AHF models; but did not increase CO. These results suggest that NIC improves hemodynamics in dogs with AHF mainly by reducing afterload without adversely affecting the cardiac contractility or conduction system, while NTG exerts its effect on AHF by reducing preload. NIC injection would thus appear to be beneficial in the treatment of AHF.

Pharmacological profile of nicardipine hydrochloride in anesthetized dogs with acute heart failure. Part 2: Effect on myocardial metabolism

The effect of nicardipine hydrochloride (NIC, CAS 54527-84-3, Perdipine) on myocardial metabolism was investigated in an experimental model of ischemic acute heart failure (AHF) induced by coronary ligation in anesthetized dogs. The left anterior descending and/or circumflex coronary ligation decreased coronary sinus blood flow (CBF), maximum rate of rise of left ventricular pressure (max. dp/dt), cardiac output (CO) and stroke volume (SV), and increased left ventricular end-diastolic pressure, indicating the development of AHF. In this ischemic AHF model, NIC (3 micrograms/kg/min i.v. infusion for 15 min) increased CBF, CO and SV, and reduced systemic and coronary artery resistances, resulting in the improvement of AHF. During the effective period, NIC decreased myocardial oxygen consumption and the coronary arterio-venous difference of oxygen content, carbon dioxide pressure and pH. At the same time, NIC did not decrease the lactate extraction. These results suggest that NIC improves hemodynamics and the balance of myocardium oxygen supply and demand in dogs with AHF by means of reducing afterload and dilating coronary artery.

Effects of YM175, a new-generation bisphosphonate, on hypercalcemia induced by tumor-derived bone resorbing factors in rats

YM175 (disodium cycloheptylaminomethylenediphosphonate monohydrate) is a new-generation bisphosphonate with stronger inhibitory activity on bone resorption than first-generation bisphosphonates. In the present study, the effect of YM175 on hypercalcemia induced in rats by single administration of either parathyroid hormone-related protein (PTHrP) or concomitant administration of PTHrP and interleukin 1beta (IL-1beta) was investigated. YM175 (0.01-1 mg/kg, i.v.) inhibited the increase in serum free calcium concentration induced by continuous administration of PTHrP alone (3 microg/rat/day, s.c., 7 days) dose-dependently. The inhibitory effect of YM175 appeared the day after administration and remained 3 days after administration. The effect of YM175 reached a maximum 2 days after administration, at which time the ED50 value of YM175 was calculated to be 0.041 mg/kg, i.v., revealing a potency approximately 50- and 10-fold stronger than those of either pamidronate or alendronate, respectively. In contrast, elcatonin (1-10 units/kg, s.c.) only transiently inhibited PTHrP-induced free calcium increase. YM175 (0.1-3 mg/kg, i.v.) also inhibited the increase in the serum free calcium concentration induced by continuous concomitant administration of both PTHrP and IL-1beta in a dose-dependent manner. These results indicated that YM175 is expected to be a useful drug for hypercalcemia associated with malignant tumors due to its efficacy and range of effect.

A monoclonal antibody against a hepatitis B e antigen epitope borne by six amino acids encoded by the precore region

Hepatitis B e antigen (HBeAg) polypeptide in the circulation (p17e) is composed of ten amino acids (aa) coded for by the precore region and 149 aa by the core gene of hepatitis B virus. A monoclonal antibody (Y0583A) was raised against the N-terminal ten amino acids (SKLCLGWLWG) encoded by the precore region. The binding of Y0583A with a panel of 203 decapeptides on multipins, which covered the precursor of HBeAg polypeptide made of 212 aa shifting by one aa, recognized an epitope sequenced LGWLWG representing the C-terminal six aa coded for by the precore region. This HBeAg epitope was not readily accessible on HBeAg in serum, but it became exposed and bound with Y0583A by treatment with 0.2 N NaOH. Using Y0583A, an enzyme-linked immunosorbent assay was developed for specific determination of HBeAg. The test sample was incubated with the monoclonal antibody to an HBeAg determinant encoded by the core gene (904) that had been immobilized on a solid support. Captured HBeAg was treated with 0.2 N NaOH, neutralized and released into the fluid phase. The reactant was then tested for a sandwich between monoclonal antibody (C33) to the C-terminus of the HBeAg polypeptide immobilized on a solid support and Y0583A labeled with horseradish peroxidase.

[Caregiver burden and subjective health level in primary caregivers of stroke patients]

The purpose of this study was to provide information on the burden and subjective health level experienced by caregivers of stroke patients. We assessed 32 patient/caregiver units attending a day care center, and investigated the characteristics and burden of caregivers. Subjective health level of caregivers was assessed using the Todai Health Index (THI). The functional level of patients was measured according to the Functional Independence Measure (FIM). Of the caregivers, 40.6% expressed a perception of being burdened. The burden of caregivers was associated with economic status, concern for future ability to provide care, and functional levels (ability of toileting, transfer, locomotion) of patients. Mean scale scores of THI did not differ significantly from scores for community women, and was not related to the perception of burden of caregivers. The situation of care for the subjects in this study can be considered to be relatively good. However, for the general caregiver of stroke patients, perception of burden and subjective health level may be affected to a greater extent than seen in this study.

Dopamine D3 and D4 receptor antagonists: synthesis and structure--activity relationships of (S)-(+)-N-(1-Benzyl-3-pyrrolidinyl)-5-chloro-4- [(cyclopropylcarbonyl) amino]-2-methoxybenzamide (YM-43611) and related compounds

In this study, we synthesized a series of (S)-N-(3-pyrrolidinyl)benzamide derivatives, 1, 2a-d, 5a-1, and 7, and their enantiomers, (R)-1 and (R)-5c-e, and evaluated their binding affinity for cloned dopamine D2, D3, and D4 receptors and their inhibitory activity against apomorphine-induced climbing behavior in mice. The results indicate that D2, D3, and D4 receptors have different bulk tolerance (D4 > D3 > D2) for the substituent of the 4-amino group (R1) on the benzamide nuclei and that cyclopropyl-, cyclobutyl-, and cyclopentylcarbonyl groups likely possess adequate bulkiness with respect to D3 and D4 affinity and selectivity over D2 receptors in this series. The results also suggested that the N-substituent (R2) on the pyrrolidin-3-yl group performs an important role in expressing affinity for D2, D3, and D4 receptors and selectivity among the respective subtypes. One of the compounds, (S)-(+)-N-(1-benzyl-3-pyrrolidinyl)-5-chloro-4-[(cyclopropylcarbonyl+ ++) amino]-2-methoxybenzamide (5c) (YM-43611), showed high affinity for D3 and D4 receptors (Ki values of 21 and 2.1 nM, respectively) with 110-fold D4 selectivity and 10-fold D3 preference over D2 receptors and weak or negligible affinity for representative neurotransmitter receptors. Compound 5c displayed potent antipsychotic activity in inhibiting apomorphine-induced climbing behavior in mice (ED50 value, 0.32 mg/kg sc).

In vitro pharmacological profile of YM-43611, a novel D2-like receptor antagonist with high affinity and selectivity for dopamine D3 and D4 receptors

1. We investigated some neurochemical properties of a novel benzamide, YM-43611, [(S)-N-(1-benzyl-3-pyrrolidinyl)-5-chloro-4-cyclopropylcarbonylamino+ ++-2- methoxybenzamide] in comparison with putative D2-like receptor antagonists using both rat and human cloned dopamine D2-like receptors in vitro. 2. Receptor binding studies revealed that YM-43611 had appropriately potent affinities for both rat and human D2-like receptors, with moderate selectivity for D3 receptors and high selectivity for D4 receptors over D2 receptors (Ki values (nM) for rat receptors: D2, 165; D3, 35.5; D4, 1.85, and for human receptors: D2, 42.9; D3, 11.2; D4, 2.10). 3. YM-43611 displayed weak or negligible affinity for other neurotransmitter receptors, namely D1, D5, alpha(1), alpha(2), beta, 5-HT1A, 5-HT2A, 5-HT3, H1, M1 and M2 receptors. 4. Dopamine stimulated low-Km GTPase activity on membranes from Chinese hamster ovary (CHO) cells expressing the human D2-like receptor subtype. This response to dopamine of low-Km GTPase activity was inhibited by use of putative D2-like receptor antagonists. YM-43611 showed a moderate selectivity for D3 receptors (Ki = 45.5 nM) and a high selectivity for D4 receptors (Ki = 3.28 nM) over D2 receptors (Ki = 70.6 nM). 5. Dopamine inhibited forskolin-stimulated adenylate cyclase in intact CHO cells expressing the human D2-like receptor subtype. YM-43611 shifted the inhibition curve of dopamine on respective D2-like receptor subtype-mediated cyclic AMP formation to the right in a parallel fashion, showing a pA2 value of 7.42 (38.1 nM) for D2 receptors, a pKB value of 8.06 (8.68 nM) for D3 receptors, and a pA2 value of 8.42 (3.77 nM) for D4 receptors. 6. YM-43611 but not the other D2-like receptor antagonists exhibited good selectivity with respect to dual antagonism for D3 and D4 receptors in both receptor binding and functional assays. 7. These results indicate that YM-43611 is a novel D2-like receptor antagonist with high potency and selectivity for both D3 and D4 receptors. YM-43611 is therefore expected to be valuable in exploration of the physiological role of D3 and D4 receptors.

YM90K: pharmacological characterization as a selective and potent alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate/kainate receptor antagonist

We investigated the pharmacological properties and neuroprotective actions of a novel alpha-amino-3-hydroxy-5-methylisoxazole-y-propionate (AMPA)/kainate receptor antagonist, [6-(1H-imidazol-1-yl)-7-nitro-2,3-(1H,4H)-quinoxalinedione hydrochloride (YM90K); formerly YM900], in comparison with those of 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline (NBQX). YM90K selectively displaced [3H]-AMPA binding (Ki = 0.084 microM) and was less potent in inhibiting [3H]-kainate (Ki = 2.2 microM), [3H]-L-glutamate (N-methyl-D-aspartate-sensitive site; Ki > 100 microM) and [3H]-glycine (strychnine-insensitive site; Ki = 37 microM) binding to rat brain membranes. YM90K co-injected with AMPA or kainate into the rat striatum protected cholinergic neurons against AMPA- or kainate-induced neurotoxicity. YM90K showed potent suppressive activity against audiogenic seizure in DBA/2 mice; ED50 values of YM90K and NBQX against tonic seizure were 2.54 and 7.17 mg/kg (i.p.), respectively. The duration of the anticonvulsant effects of YM90K and NBQX was 30 min, indicating that both compounds possess short action. In a global ischemia model, YM90K (15 mg/kg i.p. x 3), NBQX (30 mg/kg i.p. x 3) and CNQX (60 mg/kg i.p. x 3) significantly prevented the delayed neuronal death in the hippocampal CA1 region in Mongolian gerbils when administered 1 h after 5-min ischemia. In addition, the therapeutic time window for the neuroprotective effect of YM90K (30 mg/kg i.p. x 3) was 6 h. In a focal ischemia model, YM90K (30 mg/kg i.v. bolus+10 mg/kg/h for 4 h) reduced the volume of ischemic damage in the cerebral cortex in F344 rats. Thus, YM90K was shown to be a potent and selective antagonist for AMPA/kainate receptors in vitro and in vivo. This compound may provide a therapeutic effect in various neurodegenerative disorders such as ischemic stroke in which glutamate neurotoxicity is thought to play a critical role in neuronal damage.

Characterization of a novel muscarinic receptor agonist, YM796: comparison with cholinesterase inhibitors in in vivo pharmacological studies

Previous reports have shown that (+/-)-YM796 (2,8-dimethyl-3-methylene-1-oxa-8-azaspiro[4.5]decane) exhibits M1 agonistic activity and ameliorates cognitive impairment, and that the (-)-S isomer is active in in vitro studies. We report here the characterization of the (-)-S isomer, YM796 ((-)-(S)-2,8-dimethyl-3-methylene-1-oxa-8-azaspiro[4.5]decane L-tartrate monohydrate), and its (+)-R isomer in in vivo pharmacological studies in comparison with the cholinesterase inhibitors tacrine, amiridine and E-2020. YM796 (0.031-0.5 mg/kg p.o.), like the racemate, reversed the cognitive impairment in passive avoidance tasks of rats with nucleus basalis magnocellularis lesions, whereas (+)-R-YM796 was ineffective in this experimental amnesia. YM796 exhibited only weak effects on mouse salivation and hypothermia, a peripheral cholinergic response and a central cholinergic response, respectively. The (+)-R isomer, however, failed to induce these cholinergic responses. YM796 also ameliorated the memory deficits induced by scopolamine in rats and electroconvulsive shock in mice. The potency of YM796 in these experimental amnesia models was over a 100 times greater than that of tacrine, over 10 times greater than that of E-2020, and 6 times greater than that of amiridine. In salivary secretion and hypothermia, YM796 was 2-4 times weaker than tacrine and E-2020, and 1-2 times stronger than amiridine. Thus, YM796's ratio of anti-amnesic effects to salivary secretion and hypothermia was much greater than that of the cholinesterase inhibitors tested.(ABSTRACT TRUNCATED AT 250 WORDS)

A redox factor protein, ref1, is involved in negative gene regulation by extracellular calcium

A rise in extracellular calcium (Ca2+e) suppresses not only secretion of parathyroid hormone (PTH) but also expression of the PTH gene to ensure constant plasma Ca2+ level. A nuclear protein(s) in a wide variety of cells bound to the specific DNA elements (negative Ca2+ responsive elements, nCaREs) in the human PTH gene in sequence-specific and Ca2+e concentration-dependent manners. Our Southwestern cloning revealed that a redox factor protein (ref1), which was known to activate several transcription factors via alterations of their redox state, belonged to an nCaRE binding protein. The level of ref1 mRNA as well as of its protein was elevated by an increase in Ca2+e concentration. In gel shift assay, anti-ref1 antibody eliminated formation of the nCaRE-protein complex. We also found that there was another protein(s) interacting with nCaREs and ref1. Further, experiments with an antisense-ref cDNA expression vector introduced into cultured cells suggested that DNA (nCaRE)-ref1 interaction led to Ca2+e-mediated transcriptional suppression. Thus, it is concluded that ref1 possesses transcription repressor activity in addition to its function as a transcriptional auxiliary protein.

Transmission of hepatitis C in an isolated area in Japan: community-acquired infection. The South Kiso Hepatitis Study Group

BACKGROUND/AIMS

The spread of hepatitis C virus (HCV) infection not due to drug needle sharing or transfusion is largely unknown in communities. A search for risk factors for HCV infection in an endemic area might elucidate inapparent modes of transmission.

METHODS

We conducted screening for hepatitis virus markers and parenteral exposures to blood among 435 inhabitants in an isolated area known for its endemicity for non-A, non-B hepatitis and in a nonendemic area with 1542 inhabitants.

RESULTS

The prevalence of hepatitis B surface antigen was the same in both areas. The prevalence of antibody to HCV verified by the recombinant immunoblot assay was 32.4% in the highly endemic area and 2.3% in the nonendemic area (P < 0.001). Risk factors for HCV infection in the highly endemic area were complex but included folk remedies such as acupuncture and "vacuuming" for congested blood in muscle by the use of a warm glass bottle.

CONCLUSIONS

Folk remedies such as acupuncture and cutting of the skin using nonsterilized knives should be considered as possible routes of HCV transmission not associated with blood transfusion or sharing of drug paraphernalia.

Type C chronic hepatitis associated with thrombocytopenia in two patients

Portal hypertension in the presence of chronic hepatitis is generally thought to develop during the progression of the chronic hepatitis to cirrhosis. Before the establishment of assays for diagnosing hepatitis C virus infection, such a case of portal hypertension without liver cirrhosis could be misdiagnosed as idiopathic portal hypertension. It had not fully determined whether portal hypertension might precede the onset of cirrhosis in type C chronic hepatitis. This report presents two cases of women with chronic hepatitis C who developed severe thrombocytopenia; each showed splenomegaly and hypersplenism due to portal hypertension. Angiographic study and histological analysis were conducted to determine the cause of the portal hypertension. Histological evaluation showed an intrahepatic presinusoidal block pattern and fibrotic changes in the periportal area, but no evidence of liver cirrhosis or of other incidental complications such as idiopathic portal hypertension. Both of these patients exhibited normal platelet counts after splenectomy. Thus, type C chronic hepatitis can lead to portal hypertension, as demonstrated in these two patients.