Prediction of Functional Outcome in Stunned Myocardium after Myocardial Infarction using BMIPP and Tetrofosmin Imaging

The predictive value of combined 123iodine-labelled 15-( p-iodophenyl)-3 R,S-methyl pentadecanoic acid imaging (123I-BMIPP) and early technetium-99m (99mTc)-tetrofosmin imaging was compared with combined 123I-BMIPP and delayed 99mTc-tetrofosmin or 123I-BMIPP and thallium-201 (201Tl) imaging for functional outcome of stunned myocardium after acute myocardial infarction (AMI) in 37 patients with AMI. All patients underwent successful percutaneous coronary intervention with/without stenting within 24 h of symptoms. Resting 201Tl, 99mTc-tetrofosmin and 123I-BMIPP imaging were performed within 10 days of hospital admission; 99mTc-tetrofosmin imaging was also performed 6 months later. Segments were mismatched when the 123I-BMIPP score was greater than the 99mTc-tetrofosmin or 201Tl scores, and were matched when all scores were the same. Left ventricular function was estimated using wall motion score. Sensitivity and regional wall motion were significantly better in mismatching 99mTc-tetrofosmin-early/123I-BMIPP segments than mismatching 201Tl/123I-BMIPP or 99mTc-tetrofosmin-delayed/123I-BMIPP segments. It is concluded that mismatching of 123I-BMIPP and early 99mTc-tetrofosmin uptake can predict improvement in wall motion of stunned myocardium better than the other two imaging combinations.

Left ventricular myocardial remodeling and contractile state in chronic aortic regurgitation

BACKGROUND

In chronic aortic regurgitation, eccentric hypertrophy, with combined concentric hypertrophy of the left ventricle, is an important adaptive response to volume overload, which in itself is a compensatory mechanism for permitting the ventricle to normalize its afterload and to maintain normal ejection performance (physiologic hypertrophy). However, progressive dilatation of the left ventricle leads to depressed left ventricular (LV) contractility and myocardial structural changes, including cellular hypertrophy and interstitial fibrosis (pathological hypertrophy).

HYPOTHESIS

The study was undertaken to determine the relationship between left ventricular myocardial structure and contractile function in 14 patients with chronic aortic regurgitation by cardiac catheterization and endomyocardial biopsies.

METHODS

Myocardial cell diameter and percent interstitial fibrosis were obtained from biopsy samples. Contractile function was evaluated from the ratio of end-systolic wall stress to end-systolic volume index (ESS/ESVI) and the ejection fraction-end-systolic stress (EF-ESS) relationship, which was obtained from 30 normal control subjects.

RESULTS

Myocardial cell diameter correlated significantly with the ESVI (r = 0.72, p < 0.005), ejection fraction (r = -0.58, p < 0.05), and ESS/ESVI (r = -0.58, p < 0.05). The percent interstitial fibrosis also correlated inversely with ESS/ESVI (r = -0.71, p < 0.005). Compared with very few patients with an ESVI < 70 ml/m2, the majority of patients with ESVI > or = 70 ml/m2 had a cell diameter of > or = 30 microns and a percent interstitial fibrosis of > or = 10%. The nine patients who had depressed contractile function, as assessed from the EF-ESS relationship, had a higher percent interstitial fibrosis (p < 0.05) than five patients showing a normal EF-ESS relationship, despite the fact that there was no significant difference in myocardial cell diameter between them. Thus, advanced cellular hypertrophy and excessive interstitial fibrosis were significantly and independently associated with myocardial contractile dysfunction and appeared to be responsible for ventricular remodeling.

CONCLUSION

Our findings suggest that in many patients with aortic regurgitation, eccentric hypertrophy changes its nature from physiologic to nonphysiologic during the earlier stages in the course of the disease rather than during the stage described previously.

Early ultrasonographic diagnosis and clinical follow-up of hepatic veno-occlusive disease after allogeneic bone marrow transplantation in a patient with acute lymphoblastic leukemia

Hepatic veno-occlusive disease (VOD) is a typical complication occurring soon after allogeneic hematopoietic stem cell transplantation (HST), characterized by jaundice, painful liver enlargement, and weight gain due to fluid retention. The study reported here concerns a patient with VOD after allogeneic HST. Hemodynamic evaluation using ultrasonography revealed reversed portal venous flow before elevation of serum bilirubin, in addition to gallbladder wall thickening, ascites, and hepatomegaly. Quantitative evaluation using abdominal ultrasonography showed improvement in the reversed portal venous flow before the peaking of the serum bilirubin level and coagulopathy. This analysis was useful for both early diagnosis and clinical follow-up of VOD.

Modified ELISPOT assay may predict T-cell hyporesponsiveness to non-inherited maternal antigens

Clinical reports have suggested the existence of immunological tolerance to noninherited maternal antigens (NIMA) in human leukocyte antigen (HLA) mismatched allogeneic stem cell transplantation (allo-SCT). We studied the T-cell reactivity using IFN-gamma enzyme-linked immunospot (ELISPOT) assay in three HLA fully matched allo-SCT cases and one healthy volunteer family case. In HLA fully matched allo-SCT cases, ELISPOT assay could detect the hyporesponsiveness of T cells from donors to the B cells from recipients. Moreover, ELISPOT assay showed that the T cells from an individual responded to B cell from his mother significantly weakly than those from an unrelated HLA-haploidentical individual. These observations suggest that our IFN-gamma ELISPOT assay-based method may predict the presence of immunological tolerance to NIMA.

Control of the magnetoelectric domain-wall stability by a magnetic field in a multiferroic MnWO4

The relation between the orientation of the magnetic field and the flopped ferroelectric polarization has been investigated for multiferroic MnWO4. The ferroelectric single-domain state is retained across the polarization flop process when the direction of the applied magnetic field slightly deviates from the b axis within the ab plane. Furthermore, the electric polarization in the high-field P parallela phase is reversed when the P parallelb-to-P parallela transition takes place while decreasing and increasing the magnetic fields oppositely canted from the b axis. These results indicate that the symmetry breaking induced by a canted magnetic field determines the direction of the polarization flop, which corresponds to the direction of the vector spin chirality. The stability of the magnetoelectric domain walls in a canted magnetic field play a key role in the directional control of the electric polarization flop phenomenon.

Magnetic control of crystal chirality and the existence of a large magneto-optical dichroism effect in CuB2O4

The possibility of a magnetic field controlling the chirality of matter has been debated for a long time. Here, we report the successful induction of chirality in the noncentrosymmetric canted antiferromagnet, CuB2O4, by application of a low intensity static magnetic field. The chirality is reversed by a 90 degrees rotation of the direction of the magnetic field. The induction of chirality by a magnetic field gives rise to a gigantic enhancement of magnetochiral dichroism in this material. The ability to switch handedness in combination with this large magnetochiral optical effect allows us to design new optical devices such as a magnetically controllable isolator.

In vitro drug-drug interaction studies with febuxostat, a novel non-purine selective inhibitor of xanthine oxidase: plasma protein binding, identification of metabolic enzymes and cytochrome P450 inhibition

1. The potential for drug-drug interactions with febuxostat was examined in the following three in vitro systems: the characteristics of the binding of febuxostat to human plasma proteins; identification of the cytochrome P450 (CYP) and UDP-glucuronosyltransferase (UGT) enzymes participating in the metabolism of febuxostat; and the potential inhibitory effects of febuxostat on typical CYP reactions. 2. The results have shown that the presence of ibuprofen or warfarin did not change the plasma protein binding of febuxostat, and that febuxostat did not influence the plasma protein binding of ibuprofen or warfarin. These results indicate that there is little possibility that febuxostat causes a drug-drug interaction by binding to albumin. 3. The UGT 1 and 2 families were involved in the glucuronidation, and several CYPs participated in the metabolism of febuxostat, suggesting that there is little possibility that the blood concentration of febuxostat varies widely even if febuxostat is concomitantly administered with drugs that inhibit CYP or UGT enzyme. Examination of the inhibitory effect of febuxostat on CYP enzymes suggests that febuxostat minimally inhibits the activities of any CYP. 4. The results demonstrate that febuxostat is a novel anti-hyperuricaemia drug with low drug-drug interaction potential in clinical use.

Expression of inwardly rectifying K+ channels in the carotid body of rat

The inwardly rectifying K+ channels, Kir1.1, Kir2.3, Kir4.1-Kir5.1, and Kir4.2-Kir5.1, are candidate chemosensory molecules for CO2/H+. Here, we determined the mRNA expression and immunohistochemical localization of these channels in the carotid body (CB) and petrosal ganglion (PG) of the rat. RT-PCR analysis revealed mRNA expression of Kir4.1 and Kir5.1 in CB, and Kir1.1, Kir4.1, and Kir5.1 in PG. Immunohistochemistry identified the glomus cells in CB to express both Kir4.1 and Kir5.1 protein, while the nerve fibers in CB were immunoreactive for Kir1.1, Kir4.1, and Kir5.1. In the PG, immunoreactivity for Kir1.1, Kir4.1, and Kir5.1 was observed in some ganglion cells. Our findings suggest that Kir channels in the peripheral chemoreceptors play a role in sensing hypercapnic acidosis and maintaining the resting membrane potentials.

Distribution of Porphyromonas gingivalis fimA genotypes in cardiovascular specimens from Japanese patients

INTRODUCTION

Porphyromonas gingivalis, a major periodontal pathogen, is gaining increasing attention for its possible association with cardiovascular diseases. Its fimbriae are classified into six genotypes (types I-V and Ib) based on the diversity of the fimA genes encoding the fimbrial subunits. In this study, fimA genotypic distribution was analyzed in P. gingivalis-infected cardiovascular specimens.

METHODS

A total of 112 heart valves and 80 atheromatous plaque specimens were collected from patients undergoing cardiovascular surgery, as well as 56 dental plaque specimens. Bacterial DNA was extracted from each, and polymerase chain reaction analysis was carried out with a P. gingivalis-specific set of primers. P. gingivalis-positive specimens were further analyzed to discriminate the fimA genotype using polymerase chain reaction with fimA type-specific primer sets.

RESULTS

P. gingivalis was detected in 10.4% of the cardiovascular specimens and 50.0% of the dental plaque samples. In the latter, type II was most frequently detected (35.7%), followed by types I (28.6%) and IV (21.4%), while types IV and II were detected with considerable frequencies of 45.0% and 30.0%, respectively, in the cardiovascular specimens. In contrast, the occurrence of type I was limited (5.0%) in the cardiovascular specimens.

CONCLUSION

These results suggest that specific fimA genotypic clones, which are reportedly associated with periodontitis, are also frequently harbored in cardiovascular specimens, indicating the possible involvement of type II and IV clones in the initiation and progression of cardiovascular diseases.

Optimized dosage and frequency of cefozopran for patients with febrile neutropenia based on population pharmacokinetic and pharmacodynamic analysis

OBJECTIVES

To establish a cefozopran (a fourth-generation cephem) population pharmacokinetic model using patient data and use it to explore alternative dosage regimens that could optimize the currently used dosing regimen to achieve higher likelihood of pharmacodynamic exposure against pathogenic bacteria.

METHODS

We conducted a prospective clinical trial of cefozopran for haematological patients with febrile neutropenia (FN). Twenty-two patients (30 episodes) were selected to receive intravenous cefozopran every 8 h on a daily basis. We gathered concentration data and performed the NONMEM program. The Monte Carlo simulation was performed to assess the pharmacodynamic exposure based on the population pharmacokinetics and MIC.

RESULTS

The NONMEM program demonstrated that a two-compartment model provided a best fit for the data, that is, CL of 4.62 (L/h), V1 of 10.3 (L), Q of 4.47 (L/h), and V2 of 4.48 (L). On the basis of the Japanese national surveillance findings for Pseudomonas aeruginosa, methicillin-sensitive Staphylococcus aureus, coagulase-negative Staphylococcus, viridans group streptococci, Escherichia coli and Klebsiella pneumoniae, Monte Carlo simulation data showed that probability of target attainment(T>MIC = 70%) is 67% to 97% for dosing every 8 h, and 48% to 88% for dosing every 12 h. For the patients in whom the efficacy of cefozopran could be evaluated, 17 of 22 patients (77.2%) survived the episode of FN without requiring further antibacterial treatment.

CONCLUSIONS

Our study proved that Monte Carlo simulation based on population pharmacokinetics can determine optimized dosage and method. The optimal regimen for this cephem was found to be three times daily.

Cellular adaptations in soleus muscle during recovery after hindlimb unloading

AIM

We used a model of chronic unloading followed by reloading to examine the apoptotic responses associated with soleus muscle atrophy and subsequent recovery.

METHODS

Male Wistar rats were subjected to hindlimb unloading (HU) for 2 weeks and subsequent reloading for 0, 3, 7 and 14 days. One-half of the HU-reloaded rats were administered cyclosporine A (CsA), a calcineurin (CaN) inhibitor.

RESULTS

There was fibre atrophy (73%) and a decrease in slow type I fibre/myosin heavy chain (MyHC) composition in the soleus muscle after 2 weeks of HU. Fibre size and type I MyHC composition recovered to near the age-matched control levels by recovery day 14 in non-treated, but not in CsA-treated, rats. Myonuclear number was lower and the number of apoptotic nuclei higher in 2-week HU than control rats. These values returned to control levels after 7 and 14 days of recovery, respectively, in both HU-recovery groups. After 2 weeks of HU, the levels of heat shock proteins (Hsp) 60 and 72, mitochondrial cytochrome c oxidase subunit IV (Cox IV), and peroxisome proliferator-activated receptor gamma coactivator 1 (PGC-1) proteins were lower than control. The levels of all of these proteins gradually increased to or above the control levels during cage recovery in both groups.

CONCLUSION

Our results indicate that apoptotic mechanisms are involved in the modulation of myonuclear number during chronic unloading and subsequent reloading. Furthermore, it appears that CaN is related to fibre size and phenotype adaptations, but not to apoptotic responses.

Polarization reversal in multiferroic TbMnO3 with a rotating magnetic field direction

For the memory application of magnetoelectric multiferroics, not only bistability (i.e., ferroelectricity) but also the switching of the polarization direction with some noneverlasting stimulus is necessary. Here, we report a novel method for the electric polarization reversal in TbMnO3 without the application of an electric field or heat. The direction of the magnetic-field-induced polarization along the a axis (Pa) is memorized even in the zero field where Pa is absent. The polarization direction can be reversed by rotating the magnetic-field direction in the ab plane.

Possible case of potentiation of the antiplatelet effect of cilostazol by grapefruit juice

We present a case of purpura associated with concomitant ingestion of cilostazol, aspirin and grapefruit juice. A 79-year-old man with atherosclerosis obliterans, taking cilostazol and aspirin, complained of purpura. Interview by a pharmacist revealed that he had been taking grapefruit juice for a month. His purpura disappeared upon cessation of grapefruit juice, although his medication was not altered. The most probable cause of his purpura is an increase in the blood level of cilostazol because of the inhibition of cilostazol metabolism by components of grapefruit juice. Aspirin may possibly have potentiated the risk of purpura. Grapefruit juice should be avoided in patients taking cilostazol, especially in patients being concomitantly treated with other anticoagulants.

[Prophylactic effect of tropisetron hydrochloride against nausea and vomiting in patients receiving chemotherapy for hematological malignancies]

To establish the effectiveness of oral 5-HT(3) antagonist, oral 5 mg tropisetron was introduced in the 21 cases with hematological malignancies for the prevention of chemotherapy-induced nausea and vomiting. Nausea and vomiting did not develop in 81% of patients receiving the tropisetron in this study. The results suggested that oral tropisetron is effective for the control of acute, and to a lesser extent, delayed, nausea and vomiting. The drug enhanced patients' quality of life and reduced the clinical cost. In conclusion, tropisetron is effective for the prevention of chemotherapy-induced nausea and vomiting in treatment for hematological malignancies. It is suitable as first-line therapy for outpatients.

Detection and serotype distribution of Actinobacillus actinomycetemcomitans in cardiovascular specimens from Japanese patients

Actinobacillus actinomycetemcomitans, an important pathogen in periodontitis, has also been detected in cardiovascular tissues. Sixty heart valves were collected during valve replacement surgery from 60 patients (one from each), 10 were from patients with infective endocarditis (IE group) and 50 were from patients with other valvular diseases (non-IE group). In addition, 46 samples of aneurysmal tissue were taken from 46 patients with a thoracic or abdominal aneurysm (Aneurysm group, one from each). Dental plaque samples were taken from 54 of the patients, 31 in the IE and non-IE groups and 23 in the aneurysm group. First, the distribution of A. actinomycetemcomitans in all specimens was analysed using a polymerase chain reaction method, which resulted in a positive reaction in 33 (31.1%) of the cardiovascular specimens and 25 (46.3%) of the dental plaque samples. Next, using serotype-specific sets of primers, the serotype distribution of A. actinomycetemcomitans in the cardiovascular specimens and dental plaque samples was found to be significantly different compared to dental plaque samples from Japanese subjects reported previously.

Orbital ordering and magnetic field effect in MnV2O4

We studied the structural properties of an orbital-spin-coupled spinel oxide, MnV2O4, mainly by single-crystal x-ray diffraction measurement. It was found that a structural phase transition from cubic to tetragonal and ferrimagnetic ordering occur at the same temperature (Ts,TN=57 K). The structural phase transition was induced also by magnetic field above Ts. In addition, magnetic-field-induced alignment of tetragonal domains results in large magnetostriction below Ts. We also found that the structural phase transition is caused by the antiferro-type ordering of the V t2g orbitals.

γδT cells kill myeloma cells by sensing mevalonate metabolites and ICAM-1 molecules on cell surface

We evaluated the mechanism of recognition of myeloma cells by gammadeltaT cells. The expanded gammadeltaT cells killed RPMI8226 and U266 myeloma cells in a gammadeltaT-cell dose-dependent manner. Pretreatment of myeloma cells with zoledronic acid or mevastatin showed that gammadeltaT cells kill myeloma cells by recognizing the mevalonate metabolites. The expression level of intercellular cell adhesion molecule-1 (ICAM-1) on myeloma cells correlates with the cytotoxicity by gammadeltaT cells. Pretreatment of RPMI8226 and U266 with an anti-ICAM-1 monoclonal antibody inhibited their cytolysis. Moreover, AMO-1 myeloma cells transfected with of human ICAM-1 cDNA were susceptible to gammadeltaT cells compared to parental AMO-1 cells. In conclusion, gammadeltaT cells recognize the mevalonate metabolites and ICAM-1 on myeloma cells.

Hyperbaric oxygen in addition to antibiotic therapy is effective for bisphosphonate-induced osteonecrosis of the jaw in a patient with multiple myeloma

A 60-year-old man with multiple myeloma (MM) (IgG-kappa, stage IIIA) had been treated with minodronate at 6 mg orally as a phase 1 clinical trial for myeloma bone disease for 13 months (total dose, 4032 mg). Then he received incadronate at 10mg intravenously every 1 to 4 weeks (total dose, 350 mg). In July 2005, he complained of mild right mandibular pain, and bone scintigram showed a hot spot at the right side of the mandible. Panoramic radiograph showed osteonecrosis of the jaw (ONJ) and axial and 3-dimensional computed tomography confirmed ONJ. Oral examination showed massive gingival swelling of the right side of the mandible without exposed necrotic bone. He was given clarithromycin in addition to levofloxacin, followed by hyperbaric oxygen (HBO) therapy, which resulted in the complete disappearance of the pain. This is a first reported case of ONJ induced by incadronate. The present case suggests that early detection of ONJ by regular dental check-ups is important in the management of patients with MM who have received bisphosphonate therapy, and HBO in combination with antibiotic therapy is effective in the early stage of ONJ.

Rotavirus-neutralizing antibodies inhibit virus binding to integrins alpha 2 beta 1 and alpha 4 beta 1

Rotavirus outer capsid proteins VP5(*), VP8(*) and VP7 elicit neutralizing, protective antibodies. The alpha 2 beta 1 integrin is a cellular receptor for rotavirus that is bound by VP5(*). Some rotaviruses also recognize the alpha 4 beta 1 integrin. In this study, the effects of antibodies to rotavirus on virus binding to recombinant alpha 2 beta 1 and alpha 4 beta 1 expressed on K562 cells were determined. All neutralizing monoclonal antibodies to VP5(*) tested (YO-2C2, 2G4, 1A10) and two to VP7 (RV-3:2, RV-4:2) inhibited rotavirus binding to alpha 2 beta 1. Rotavirus binding to alpha 4 beta 1 was reduced by 2G4 and neutralizing antibody F45:2, directed to VP7. However, a neutralizing antibody to VP8(*) (RV-5:2) and one to VP7 (RV-3:1) did not affect rotavirus binding to these integrins. Virus-cell binding was unaffected by non-neutralizing antibody RVA to the rotavirus inner capsid protein VP6. The attachment of human rotavirus strain Wa to these integrins was inhibited by infection sera with neutralizing activity collected from two children hospitalised with severe rotavirus gastroenteritis. A negative reference serum did not affect rotavirus-cell attachment. As the binding of rotaviruses to alpha 2 beta 1 and alpha 4 beta 1 is inhibited by neutralizing antibodies to VP5(*) and VP7, and serum from children with rotavirus disease, rotavirus recognition of these integrins may be important for host infection.

Immunohistochemical Examination of Epiphyseal Growth Plates of Japanese Brown Cattle with Chondrodysplasia

A new type of inherited chondrodysplasia is described in Japanese Brown cattle, but the basic defects of the epiphyseal growth plate (EGP) in the limb long bones, and proliferation and differentiation of the chondrocytes in the EGP, are not yet understood. In the present study, the EGPs of the limb long bones in eight cases of chondrodysplasia and four normal (control) cattle were examined histologically and immunohistochemically. In the control cattle, proliferative chondrocytes (PCs) and hypertrophic chondrocytes (HCs) were arranged in columns parallel to the long axis of the bone, and HCs were situated on the metaphyseal side of the EGP. In all the affected cattle, many chondrocytes with a hypertrophic appearance were detected in the inner areas of the central portion of the EGP. The PC columns were short and arranged irregularly. Bone tissue and small blood vessels were found frequently in these areas. Six affected cattle showed complete EGP-closure. Backscattered electron (BSE) imaging showed that the calcified cartilage matrix was restricted to the lower region of the hypertrophic zone (HZ) of the EGP in the control cattle, while the calcified cartilage matrix and bone tissue were scattered in the inner areas of the EGP in all the chondrodysplastic cattle. Immunohistochemistry revealed type X collagen in the HCs and cartilage matrix of the HZ in the control cattle. In all the affected cattle, type X collagen was detected in apparently hypertrophic chondrocytes in the inner areas of the EGP. Type II collagen was detected in the entire EGP in all the affected cattle, as in the controls. BrdU (5-bromo-2'-deoxyuridine), injected intravenously 1h before euthanasia was detected in many PCs in the EGP in the control cattle; none, however, was detected in the central portion of the EGP in any affected animal. These observations indicate that differentiation into HCs and calcification of cartilage matrix occur in the inner areas of the central portion of the EGP in chondrodysplasia of Japanese Brown cattle. Differentiation into the HCs at this abnormal site may be caused by the inadequate proliferation and disorganization of the PCs. Premature EGP-closure, observed commonly in chondrodysplasia of Japanese Brown cattle, was thought to be caused by replacement of the calcified cartilage in the inner areas of the EGP by bone tissue.

Effect of antipsychotic replacement with quetiapine on the symptoms and quality of life of schizophrenic patients with extrapyramidal symptoms

Replacement of antipsychotic drugs with quetiapine (QTP) was tried in a naturalistic setting in chronic schizophrenic patients who still showed moderate psychiatric symptoms and either showed extrapyramidal symptoms (EPS) or took anti-parkinson drugs for the EPS. QTP was added on and gradually increased while the previous drugs were tapered and discontinued whenever possible. Clinical symptoms, objective and subjective QOL, and EPS were measured before and 6 months after QTP addition, using Brief Psychiatric Rating Scale (BPRS), Quality of Life Scale (QLS), Schizophrenia Quality of Life Scale (SQLS) and Drug-Induced Extrapyramidal Symptom Scale (DIEPSS), respectively. Twenty-one patients completed the trial and received the assessment. It was found that replacement with QTP-improved clinical symptoms, objective and subjective QOL and EPS. This improvement was equally observed in not only patients who switched to QTP monotherapy (n = 11) but also patients who took QTP together with reduced small doses (4.4 +/- 4.3 mg/day) of previous drugs (n = 11). The results suggest that replacement with QTP improves symptoms as well as objective and subjective QOL in a subgroup of schizophrenia.

Ferroelectric polarization flop in a frustrated magnet MnWO4 induced by a magnetic field

The relationship between magnetic order and ferroelectric properties has been investigated for MnWO4 with a long-wavelength magnetic structure. Spontaneous electric polarization is observed in an elliptical spiral spin phase. The magnetic-field dependence of electric polarization indicates that the noncollinear spin configuration plays a key role for the appearance of the ferroelectric phase. An electric polarization flop from the b direction to the a direction has been observed when a magnetic field above 10 T is applied along the b axis. This result demonstrates that an electric polarization flop can be induced by a magnetic field in a simple system without rare-earth 4f moments.

Dynamical behavior of the motions associated with the nonlinear periodic regime in a laboratory plasma subject to delayed feedback

Time-delayed feedback is applied to the motions associated with the nonlinear periodic regime generated due to current-driven ion acoustic instability; this is a typical instability in a laboratory plasma, and the dynamical behavior is experimentally investigated using delayed feedback. A time-delayed autosynchronization method is applied. When delayed feedback is applied to the nonlinear periodic orbit, the periodic state changes to various motions depending on the control parameters, namely, the arbitrary time delay and the proportionality constant. Lyapunov exponents are calculated in order to examine the dynamical behavior.

Analysis of genetic factors related to preferential selection of the NSP1 gene segment observed in mixed infection and multiple passage of rotaviruses

Reassortment is one of the major evolutionary mechanisms of the rotavirus genome. Preferential selection (assortment) of the NSP1 gene segment from either of the parental viruses after coinfection of these viruses has been reported as a notable finding in reassortment. To analyze genetic factors which are associated with preferential selection of the rotavirus NSP1 gene segment into progeny viruses, mixed infection and multiple passages were performed using two panels of rotaviruses, i.e., bovine rotavirus A5 clones, and simian rotavirus SA11 and five strains of SA11-based single NSP1 gene-substitution reassortants. In the first experiment, three A5 clones (A5-10, A5-13, and A5-16) that had genetically distinct NSP1 genes in the same genetic background were used. In coinfection of these A5 clones, it was noted that the A5-10 NSP1 gene, which encodes an incomplete protein product due to presence of a nonsense codon at an unusual position, was selected more preferentially than the A5-13 NSP1 gene with intact length and structure. The A5-16 NSP1 gene, with a deletion of 500 bp, was least efficiently selected. In the second experiment, we prepared two reassortants, SOF and SRF, which have NSP1 genes from rotavirus strains OSU and RRV, respectively, in the genetic background of SA11, which were used together with previously prepared reassortants SKF, SDF, and SNF, which had NSP1 genes from strains KU, DS1, and K9, respectively. Among the 6 NSP1 genes analyzed, the NSP1 gene from SKF was most preferentially selected, followed by SNF, SOF, SDF, SA11, and SRF, in that order. Although SOF exhibited less growth efficacy than SA11, the growth rates of other reassortants were similar to that of SA11. These findings suggest that for the occurrence of preferential selection of the NSP1 gene, production of the intact NSP1 protein may not be involved, but the presence of intact length of the NSP1 gene may be required. Furthermore, it was also found that genetic similarity based on primary structure of this gene is not related to the selectivity of the NSP1 gene.

[Improvement of thrombocytopenia with normalization of thyroid function in a patient with Graves disease]

A 39-year-old man was admitted to our hospital because of hyperthyroidism complicated with fever, atrial fibrillation with rapid ventricular response and congestive heart failure. Laboratory data revealed pancytopenia with a white blood cell count of 3360/microl, Hb 9.6 g/dl, and a platelet count of 88000/ul. After initiation of treatment with 30 mg of thiamazole daily, the patient's thyroid function improved but 4 weeks later, thiamazole induced agranulocytosis occurred and the drug was discontinued. After recovery from agranulocytosis, a subtotal thyroidectomy was performed, and the patient's pancytopenia rapidly improved. In this case, hyperthyroidism itself appeared to be closely related to the development of thrombocytopenia.

Expression of Tandem P Domain K+ Channel, TREK-1, in the Rat Carotid Body

TREK-1 is one of the important potassium channels for regulating membrane excitability. To examine the distribution of TREK-1 in the rat carotid body, we performed RT-PCR for mRNA expression and in situ hybridization and immunohistochemistry for tissue distribution of TREK-1. RT-PCR detected mRNA expression of TREK-1 in the carotid body. Furthermore, in situ hybridization revealed the localization of TREK-1 mRNA in the glomus cells. TREK-1 immunoreactivity was mainly distributed in the glomus cells and nerve fibers in the carotid body. TREK-1 may modulate potassium current of glomus cells and/or afferent nerve endings in the rat carotid body.

Significance of lymph node micrometastasis in pN0 hilar bile duct carcinoma

AIMS

To examine micrometastasis in node-negative hilar bile duct carcinoma (HBDC) using an immunohistochemical method and evaluated the clinical significance.

METHODS

Four hundred and twenty three regional lymph nodes from 28 patients with node-negative HBDC who had undergone a resection were immunostained with an antibody against cytokeratins eight and 18 (CAM 5.2).

RESULTS

Lymph node micrometastasis was detected in 11 of the 28 patients and 14 of the 423 lymph nodes. Lymph node micrometastasis was significantly correlated with the pT classification (p=0.03), the histopathological grading (p=0.01) and venous invasion (p=0.05). The 5-year survival rate of the patients with lymph node micrometastasis was 21.8%, as opposed to 66.5% in the patients without micrometastasis. Patients with micrometastasis showed a significantly poorer survival rate than those without micrometastasis (p=0.02).

CONCLUSION

The results suggest that immunohistochemically detected lymph node micrometastasis has an impact on the outcome in HBDC.

The gene expression level of transforming growth factor-beta (TGF-beta) as a biological prognostic marker of hepatocellular carcinoma

The question that transforming growth factor-beta (TGF-beta) provides a tumor-suppressive or a tumor promoting role is still unknown in hepatocellular carcinoma (HCC). In the present study, we quantitatively investigated the gene expression levels of TGF-beta in liver tissues from patients with HCC. We also evaluated the prognostic importance of TGF-beta gene in HCC patients. A total of 59 patients with primary HCC who underwent hepatectomy between 1993 and 2001 were enrolled. TGF-beta gene expression levels of tumors and of noncancerous livers were analyzed by real-time reverse transcriptase polymerase chain reaction (RT-PCR). The percentage of apoptotic cells in tumor cells (apoptotic index: AI) was evaluated with immunohistochemistry. Also the expression of survivin protein (apoptosis inhibitor) in tumors was detected by immunohistochemistry. TGF-beta gene expression levels of tumors were compared with clinicopathological findings of patients. The relative expression level of TGF-beta mRNA of 59 tumor tissues did not differ from those of 8 normal liver tissues or 59 noncancerous liver tissues. The mean AI of 29 tumors with normal expression levels of TGF-beta gene (4%) was significantly higher than that of 30 tumors with low expression levels of TGF-beta gene (2.5%, p = 0.03). Thirteen out of 30 tumors (43%) with low expression level of TGF-P gene showed survivin positive, while only 4 out of 29 tumors (14%) with preserved expression of TGF-beta gene showed survivin positive. This difference was significant (p = 0.012). The overall 5-year survival rate of 29 patients with tumors with preserved TGF-beta gene prolonged to 72% compared with that of 30 patients who had tumors with suppressed TGF-beta gene (58%, p = 0.156). In HCC, TGF-beta gene may play a defensive role against tumor progression by regulating survivin protein expression and by controlling occurrence of spontaneous apoptosis in tumors.

Experimental surveillance using data on sales of over-the-counter medications--Japan, November 2003-April 2004

OBJECTIVES

This report describes a study to explore the possibility of using data on sales of over-the- counter (OTC) medications as part of a routine syndromic surveillance system aimed at early detection of infections of public health concern. A retrospective evaluation was conducted of sales of OTC medications used to treat the common cold. This report discusses the correlation of these data to influenza activity in Japan during the 2003-04 influenza season and evaluates the potential of using such data to predict influenza epidemics.

METHODS

Data from approximately 1,100 pharmacies throughout Japan collected during November 2003-April 2004 were analyzed. OTC sales data were compared with influenza incidence data (one weekly and two daily data sets) to determine correlations and predictability. Adjusted R-square was used as an index of goodness of-fit in the estimation. Data reflecting daily influenza activity were obtained from the National Surveillance of Daily Influenza Outpatients and the Mailing List-Based Influenza Epidemic Database. National sentinel surveillance data for influenza from approximately 5,000 sites nationwide also were analyzed.

RESULTS

Although a correlation was demonstrated between sales of OTC medications used to treat the common cold and concurrent influenza activity, analysis of sales data alone was not sufficient to determine influenza activity in advance even when sales promotion effects were excluded from the analysis.

CONCLUSION

Because visiting a health-care provider costs more than purchasing OTC medications, the hypothesis was formed that an ill person will purchase OTC medications first and visit a physician only if the condition does not resolve or worsens. The results of this study do not provide any clear evidence to support this hypothesis. For this reason, OTC sales do not appear to be a good candidate for a national real-time detection system for influenza epidemics in Japan.

Cell proliferation activity of proliferating bile duct after bile duct ligation in rats

The cell proliferation activity of proliferating bile ducts produced by bile duct ligation (BDL) in rats was examined histologically, immunohistochemically, and ultrastructurally. Proliferating bile ducts, which were similar to normal bile ducts, increased with time after BDL. The cell proliferation activity of proliferating bile ducts, measured using proliferating-cell nuclear antigen and 5-bromo-2'-deoxyuridine antibodies, tended to be high at 1 and 3 days after BDL and decreased progressively at 2 to 4 weeks after BDL. On the other hand, alpha-smooth muscle actin-positive myofibroblast-like cells increased continuously after BDL. These findings indicate that there is a negative correlation between the cell proliferation activity of proliferating bile ducts and that of myofibroblast-like cells.

Morphological changes in the rat endocrine pancreas within 12 h of intravenous streptozotocin administration

We examined early morphological changes in pancreatic endocrine cells within 12 h of intravenous streptozotocin (STZ) administration (60 mg/kg). Thirty rats were allocated either to a control group (vehicle alone) or to one of four experimental groups tested after 3, 6, 9 and 12 h. Karyopyknosis and cytoplasmic vacuoles were first observed in beta-cell cytoplasm 3 h after STZ administration (STZ-3 h), and the most severe damage was found in beta cells at STZ-12 h. Insulin-positive non-islet cells were observed near the intercalated duct (ICD) and/or centroacinar (CA) cells at STZ-6 h and their numbers peaked at STZ-6 h. The distribution patterns of the insulin-positive cells and those of nestin and insulin-like growth factor-1 were similar and their nuclei were positive for proliferating cell nuclear antigen. Thus, ICD cells and/or CA cells reacted immediately to transform into insulin-secreting cells to replace injured beta cells (or to compensate for the lack of beta cells) within 12 h of STZ administration.

Methotrexate-induced acute lung injury in a patient with rheumatoid arthritis

Methotrexate (MTX)-induced acute lung injury developed in a female patient with rheumatoid arthritis. She was successfully treated with high-dose glucocorticoid therapy. During her hospital stay, the serum concentration of surfactant protein (SP)-D, which was markedly elevated on admission, was finally normalized and the disease resolved. However, the serum concentration of Klebs von den Lungen (KL)-6 remained high. Although the mechanisms of lung injury by MTX have not been well defined, serial measurements of serum SPD might be useful for the clinical evaluation of drug-induced acute lung injury.

Induction of mononuclear cell infiltration into liver by Japanese herbal medicine

Juzen-Taiho-To (JTT) is a Japanese herbal medicine that has been administered mainly to patients weakened by long illness. Currently, it has also been used for cancer patients and showed antitumor effects that have been reported as phagocytosis enhancement, cytokine induction and antibody production. In this study, we examined the effect of oral administration of JTT in mice on the immunological restoration of the liver, especially focused on natural killer (NK) T-cell induction. Mice were grouped to receive JTT or placebo orally for a period of 1, 3 and 7 days. After sacrifice, the liver tissue was fixed, embedded and stained with hematoxylineosin and some antibodies by common staining methods. Transmission electron microscope (TEM) observation was also carried out. Although the JTT-treated mice had the same appearance as the non-JTT-treated mice, their livers were infiltrated by massive mononuclear cells, some of which were aggregated in clusters. Immunohistochemical staining revealed that there was abundant cytokine expression of interleukin (IL)-12 and massive infiltration of mononuclear cells with large granules in the liver of JTT-treated mice. Oral administration of JTT may induce the expression of IL-12 and be followed by immunological restoration such as NK T-cell induction in liver

Polymorphisms in the taste receptor gene (Tas1r3) region are associated with saccharin preference in 30 mouse strains

The results of recent studies suggest that the mouse Sac (saccharin preference) locus is identical to the Tas1r3 (taste receptor) gene. The goal of this study was to identify Tas1r3 sequence variants associated with saccharin preference in a large number of inbred mouse strains. Initially, we sequenced approximately 6.7 kb of the Tas1r3 gene and its flanking regions from six inbred mouse strains with high and low saccharin preference, including the strains in which the Sac alleles were described originally (C57BL/6J, Sac(b); DBA/2J, Sac(d)). Of the 89 sequence variants detected among these six strains, eight polymorphic sites were significantly associated with preferences for 1.6 mm saccharin. Next, each of these eight variant sites were genotyped in 24 additional mouse strains. Analysis of the genotype-phenotype associations in all 30 strains showed the strongest association with saccharin preference at three sites: nucleotide (nt) -791 (3 bp insertion/deletion), nt +135 (Ser45Ser), and nt +179 (Ile60Thr). We measured Tas1r3 gene expression, transcript size, and T1R3 immunoreactivity in the taste tissue of two inbred mouse strains with different Tas1r3 haplotypes and saccharin preferences. The results of these experiments suggest that the polymorphisms associated with saccharin preference do not act by blocking gene expression, changing alternative splicing, or interfering with protein translation in taste tissue. The amino acid substitution (Ile60Thr) may influence the ability of the protein to form dimers or bind sweeteners. Here, we present data for future studies directed to experimentally confirm the function of these polymorphisms and highlight some of the difficulties of identifying specific DNA sequence variants that underlie quantitative trait loci.