Genetic influences on the difference in variability of height, weight and body mass index between Caucasian and East Asian adolescent twins

OBJECTIVE

Twin studies are useful for investigating the causes of trait variation between as well as within a population. The goals of the present study were two-fold: First, we aimed to compare the total phenotypic, genetic and environmental variances of height, weight and BMI between Caucasians and East Asians using twins. Secondly, we intended to estimate the extent to which genetic and environmental factors contribute to differences in variability of height, weight and BMI between Caucasians and East Asians.

DESIGN

Height and weight data from 3735 Caucasian and 1584 East Asian twin pairs (age: 13-15 years) from Australia, China, Finland, Japan, the Netherlands, South Korea, Taiwan and the United States were used for analyses. Maximum likelihood twin correlations and variance components model-fitting analyses were conducted to fulfill the goals of the present study.

RESULTS

The absolute genetic variances for height, weight and BMI were consistently greater in Caucasians than in East Asians with corresponding differences in total variances for all three body measures. In all 80 to 100% of the differences in total variances of height, weight and BMI between the two population groups were associated with genetic differences.

CONCLUSION

Height, weight and BMI were more variable in Caucasian than in East Asian adolescents. Genetic variances for these three body measures were also larger in Caucasians than in East Asians. Variance components model-fitting analyses indicated that genetic factors contributed to the difference in variability of height, weight and BMI between the two population groups. Association studies for these body measures should take account of our findings of differences in genetic variances between the two population groups.

G1 arrest and expression of cyclin-dependent kinase inhibitors in tamoxifen-treated MCF-7 human breast cancer cells

Treatment of exponentially growing MCF-7 human breast carcinoma cells with tamoxifen (TAM) inhibits cell growth in a dose-dependent manner. However, the molecular basis for the drug's activity and its relationship to the cell cycle have not yet been clearly established. In this study, we analyzed cell cycle-related proteins used for immunoblotting and flow cytometry in TAM-treated MCF-7 cells. In addition, the ratio of apoptosis in the cell was analyzed using labeling of DNA strand breaks (TdT assay). In flow-cytometric DNA distribution analysis, the S-phase fraction showed a marked decrease and a concomitant increase in G1- and G2-phase cells accompanying the inhibitory effect of TAM; these changes were time- and dose-dependent. Immunoblotting revealed that the levels of p53 and p21(WAF1/CIP1) in TAM-treated cells increased in a time- and dose-dependent manner, whereas those of p27(KIP1) and p16 slightly increased or remained unchanged. Furthermore, cyclin D3 and B showed sharp decreases, in contrast with p53 and p21(WAF1/CIP1) DNA-apoptosis dual analysis using flow cytometry revealed that the TAM-treated samples contained apoptotic cells, the majority of which were arrested in G1 or G2 and showed suppression of Bcl-2 protein. These results suggest that the tumorigenic effect of TAM on MCF-7 cells arises through antitumor effects that are due to the expression of cyclin-dependent kinase inhibitors, especially p21(WAF1/CIP1) and these are regulated by the decrease of wild-type p53. The proposed mechanism is similar to that underlying the cytotoxic effects of other agents and ionizing irradiation that cause DNA damage.

A femtosecond laser pacemaker for heart muscle cells

The intracellular effects of focused near-infrared femtosecond laser irradiation are shown to cause contraction in cultured neonatal rat cardiomyocytes. By periodic exposure to femtosecond laser pulse-trains, periodic contraction cycles in cardiomyocytes could be triggered, depleted, and synchronized with the laser periodicity. This was observed in isolated cells, and in small groups of cardiomyocytes with the laser acting as pacemaker for the entire group. A window for this effect was found to occur between 15 and 30 mW average power for an 80 fs, 82 MHz pulse train of 780 nm, using 8 ms exposures applied periodically at 1 to 2 Hz. At power levels below this power window, laser-induced cardiomyocyte contraction was not observed, while above this power window, cells typically responded by a high calcium elevation and contracted without subsequent relaxation. This laser-cell interaction allows the laser irradiation to act as a pacemaker, and can be used to trigger contraction in dormant cells as well as synchronize or destabilize contraction in spontaneously contracting cardiomyocytes. By increasing laser power above the window available for laser-cell synchronization, we also demonstrate the use of cardiomyocytes as optically-triggered actuators. To our knowledge, this is the first demonstration of remote optical control of cardiomyocytes without requiring exogenous photosensitive compounds.

Hsp90-inhibitor geldanamycin abrogates G2 arrest in p53-negative leukemia cell lines through the depletion of Chk1

Checkpoint protein Chk1 has been identified as an Hsp90 client. Treatment with 100 nM geldanamycin (GM) for 24 h markedly reduced the Chk1 amount in Jurkat and ML-1 leukemia cell lines. Because Chk1 plays a central role in G2 checkpoint, we added GM to G2-arrested Jurkat and HL-60 cells pretreated with 50 nM doxorubicin for 24 h. GM slowly released both cell lines from doxorubicin-induced G2 arrest into G1 phase. GM also abrogated ICRF-193-induced decatenation G2 checkpoint in Jurkat and HL-60 cells. Western blot analysis showed that addition of GM attenuates doxorubicin- and ICRF-193-induced Chk1 phosphorylation at Ser345. GM, however, failed to abrogate G2 arrest in p53-positive ML-1 cells maybe due to the p21 induction. GM released HeLa cells from doxorubicin-induced G2 arrest but trapped them at M phase. Flow cytometric analysis showed that addition of GM converted doxorubicin-induced necrosis into apoptosis in Jurkat cells. Colony assay indicated that although GM has a weak cytotoxic effect as a single agent, it dramatically intensifies the cytotoxicity of doxorubicin and ICRF-193 in Jurkat and HL-60 cells. These results suggest that abrogation of G2 checkpoint by GM may play a central role in sensitizing p53-negative tumor cells to DNA-damaging and decatenation-inhibiting agents.

Relative and Combined Performance of Mammography and Ultrasonography for Breast Cancer Screening in the General Population: a Pilot Study in Tochigi Prefecture, Japan

BACKGROUND

Breast cancer screening by mammography is thought to be effective in reducing breast cancer mortality while ultrasonography is not accepted as a population screening modality, although the latter has been suggested to be useful in detection of cancer in the dense breast, relatively more typical for a younger woman.

METHODS

Mammography with medio-lateral oblique view was offered on trial in 1999-2000 for 3453 female residents in Tochigi prefecture who also underwent clinical breast examination and ultrasonography. The municipalities that provided cancer screening were informed of the final diagnosis for women with positive findings in the screening trial by doctors who performed the diagnostic evaluation. Linkage was also made between the list of participants in the trial and registrations at Tochigi Cancer Registry for breast cancer cases diagnosed during 1999-2001.

RESULTS

Thirteen cases with breast cancer were identified during a 2-year follow-up period: 10 were diagnosed subsequent to positive finding in the trial; two were negative in the trial and diagnosed 23 and 24 months after, respectively; and one had a positive finding at the trial but was undiagnosed at first and then diagnosed 18 months after the trial. Among the 11 cases judged as positive in the trial, four were judged only by mammography while three were judged only by ultrasonography. Those mammography alone-detected cases were relatively young, at 36, 40, 47 and 54 years of age, respectively, while the ultrasonography alone-detected cases were aged 50, 55 and 68, respectively.

CONCLUSIONS

Combined screening with mammography and ultrasonography may be feasible. A larger study is required to evaluate relative performance of mammography and ultrasonography in detail by characteristics of examinees and their breasts.

Diabetic retinopathy and coronary implantation of sirolimus-eluting stents

INTRODUCTION

The prognostic value of identifying the retinal status of diabetic patients undergoing coronary implantation of drug-eluting stents is unknown.

METHODS

We evaluated the outcomes of 318 consecutive patients undergoing implantation of sirolimus-eluting stents for coronary artery disease. Patients were divided into 5 groups according to the diabetic and retinal status: diabetic patients without retinopathy (43 patients); diabetic patients with nonproliferative retinopathy (34); diabetic patients with proliferative retinopathy (37); diabetic patients with unknown retinal status (30); and nondiabetic patients (174).

RESULTS

During a mean follow-up of 385 days, 64 patients had target-vessel failure (defined as a composite of death from cardiac causes, myocardial infarction, and target-vessel revascularization). At 1 year, Kaplan-Meier estimates of the rate of target-vessel failure were 15.3% for diabetic patients without retinopathy, 56.6% for those with nonproliferative retinopathy, 17.3% for those with proliferative retinopathy, 19.0% for those with unknown retinal status, and 16.0% for nondiabetic patients. After adjustment for the potential confounders and differences between groups, the relation of nonproliferative retinopathy to target-vessel failure remained significant. In an analysis in which diabetic patients without retinopathy were used as the reference group, the hazard ratios for target-vessel failure were 3.9 for those with nonproliferative retinopathy, 1.3 for those with proliferative retinopathy, 1.1 for those with unknown retinal status, and 1.4 for nondiabetic patients (P for trend = 0.015).

CONCLUSIONS

As compared with diabetic patients without retinopathy, those with nonproliferative retinopathy have an increased risk for target-vessel failure after coronary implantation of sirolimus-eluting stents.

The beneficial effect of coronary-artery-bypass surgery on survival in patients with diabetic retinopathy

OBJECTIVE

The presence of retinopathy is a predictor of mortality following coronary revascularization in diabetics. We studied whether revascularization by coronary-artery-bypass surgery (CABG), as compared with percutaneous coronary intervention (PCI), influences the prognosis in diabetics with retinopathy.

METHODS

Between April 1996 and March 2004, 1489 patients underwent revascularization as an initial procedure. Among these a total of 319 diabetics underwent retinal examination prior to the initial revascularization. These patients were classified according to whether they had retinopathy and whether they had undergone CABG, either initially or after PCI. Mortality rates were estimated from the time of initial revascularization procedure.

RESULTS

The average follow-up from the time of initial revascularization was 48.2+/-28.6 months. In 153 diabetics with retinopathy, 59 eventually underwent CABG. During the entire follow-up period, there were 2 (3.4%) deaths in diabetics with retinopathy who underwent CABG and 14 (14.9%) deaths in those who did not have CABG. Mortality curves differed significantly between the two groups (P = 0.007). After adjustment for risk factors, the relative risk of death was 0.13 afforded by CABG (95% CI, 0.03-0.62; P = 0.011). In 166 diabetics without retinopathy, mortality curves were similar between the patients who underwent CABG and those who did not have CABG (P = 0.94).

CONCLUSIONS

CABG conferred a survival advantage in diabetics with retinopathy. In contrast, no survival advantage was evident in diabetics without retinopathy undergoing CABG. Retinal status should be taken into consideration when considering revascularization strategy for diabetics who have coronary artery disease.

[Multicenter phase II trial of thrice-weekly docetaxel and weekly trastuzumab as preoperative chemotherapy in patients with HER 2-overexpressing breast cancer--Japan East Cancer Center Breast Cancer Consortium (JECBC) 02 Trial]

The efficacy and safety of combination therapy of 4 cycles with docetaxel 70 mg/m(2)every 3 weeks and trastuzumab as primary chemotherapy for operable breast cancer was determined in 21 patients (pts) by assessing the pathological complete response (pCR) rate, clinical response rate (RR), breast conservation surgery (BCS) rate and toxicities. To date, 19 pts have completed surgery. The pCR rate was 21% [95% CI 6%-46%] . The overall RR was 90% [95% CI 67%-99%] , with 5 CR, 12 PR, 2 SD and 0 PD. Grade 3 or 4 adverse events were leukopenia 48%, neutropenia 67%, hemoglobin 5%, and febrile neutropenia 10%. All non-hematological toxicities were mild and manageable. The pCR rate is not as low as that achieved in previous international studies. The combination of docetaxel and trastuzumab was a well-tolerated and very active regimen for the treatment of patients with HER 2-overexpressing operable breast cancer. This regimen promises to be one of the leading future treatments for progressive breast cancer.

Combination docetaxel and trastuzumab treatment for patients with her-2-overexpressing metastatic breast cancer: A multicenter, phase-II study

BACKGROUND

Pre-clinical and clinical studies indicate that a combination of docetaxel and trastuzumab may effectively treat patients with human epidermal growth factor receptor-2 (HER-2) overexpressing metastatic breast cancer. We evaluated the efficacy and safety of this combination in a multicenter, open-label phase II study in Japan.

METHODS

Women with metastatic breast cancer whose tumors overexpressed HER-2, as assessed by immunohistochemistry and by fluorescence in situ hybridisation, received 2 to 6 cycles of docetaxel (70 mg/m2, every 3 weeks) and trastuzumab (4 mg/kg loading dose, 2 mg/kg weekly thereafter). The primary endpoint was tumor response. Secondary endpoints were time to disease progression and adverse events.

RESULTS

Of the 40 women enrolled in the study, 27 (68%) completed 6 cycles of treatment. Three patients discontinued the study before the second cycle. Median follow-up was 20.8 months (range, 0.6 to 30.9 months). The overall response rate was 65% (26/40; 95% CI, 48% to 79%). The median time to progression was 6.8 months (range, 0.6 to 21.2 months). Of the 40 patients, 35 (88%) had grade 3 or 4 leukopenia, and 33 (83%) had grade 3 or 4 neutropenia. Most instances of leukopenia and neutropenia were manageable by reducing the dose of docetaxel or by treatment with granulocyte colony-stimulating factor. In 4 patients, left ventricular ejection fraction decreased by more than 10% from baseline.

CONCLUSIONS

The combination of docetaxel and trastuzumab was as effective as reported in other similar studies and was well tolerated in these patients.

Efficacy of nifekalant hydrochloride in the treatment of fatal ventricular arrhythmia in patients with ischemic heart disease

Ventricular tachycardia (VT), which causes hemodynamic instability, and ventricular fibrillation (VF) sometimes occur in patients with severe underlying cardiovascular disease such as myocardial ischemia or infarction, and are associated with high mortality. This report presents the efficacy of nifekalant hydrochloride (nifekalant), a pure class III antiarrhythmic agent, in treating life-threatening ventricular arrhythmia in such patients. From June 2000, when nifekalant became commercially available in Japan, to May 2003, 30 ischemic heart disease (IHD) patients with VT/VF resistant to direct-current (DC) countershock received nifekalant in our hospital. These 30 patients served as the nifekalant group in this study. As a control group, we also included 33 IHD patients with VT/VF that had been resistant to DC countershock upon or during hospitalization between January 1996 and May 2000 before nifekalant became commercially available. No significant differences were observed in patient background factors and treatments between the two groups. The rates of death within 48 hours of occurrence of VT/VF were significantly lower in the nifekalant group (7%, 2/30) than in the control group (27%, 9/33; P < 0.03). The rates of cardiac death during hospitalization were also significantly lower in the nifekalant group (40%, 12/30) than in the control group (67%, 22/33; P < 0.03). The rates of survival until hospital discharge were significantly higher in the nifekalant group (57%, 17/30) than in the control group (30%, 10/33; P < 0.03). Multivariate analysis of all 63 patients revealed nifekalant administration was the factor that significantly improved the mortality (odds ratio for cardiac death, 0.26; 95% confidence interval (CI), 0.07 to 0.95; P = 0.041). Nifekalant improves the prognosis for life-threatening ventricular arrhythmia in IHD patients.

Chromosomal assignment of LASP1 and LASP2 genes and organization of the LASP2 gene in chicken

Lasp-1 and lasp-2 are actin-binding proteins that contain a LIM domain, two nebulin repeats and an SH3 domain with significant identity. We determined the chromosomal locations of the LASP1 and LASP2 genes in chicken by fluorescence in situ hybridization. The LASP1 gene was localized to a pair of microchromosomes and the LASP2 gene was localized to chromosome 2p3.1, indicating that the chromosomal locations of the LASP1 and LASP2 genes are highly conserved between chicken and human. The comparison of genomic and cDNA sequences of chicken lasp-2 and nebulette, a nebulin-related protein in muscle, suggested that both the corresponding mRNAs shared exons in the same manner as their human homologues. When compared with the domain structure of nebulette, another nebulin repeat was predicted for lasp-2, and all the nebulin repeats of lasp-2 were better conserved than those in nebulette. We also found the exon boundaries in nebulin repeats of lasp-2 were similar to those of other nebulin-related proteins.

Sprouting from arteriovenous shunt vessels with increased blood flow

The purpose of this study was to evaluate the effect of increased blood flow on angiogenesis at the large vessels. The arteriovenous (AV) shunt was made on the thigh of male Wistar rats (n = 27) to increase blood flow, wrapped with artificial skin dermis, which consisted of a silicon outer layer, and isolated from surrounding tissues. Blood flow increased from 2.40 +/- 0.77 to 35.8 +/- 8.7 ml min(-1) (14.9 times), and the shear stress index (relative value of shear stress) increased from 10.7 +/- 3.6 to 73.4 +/- 18.1 (6.85 times) 60 min after the shunt formation. Newly formed vessels were observed around the AV shunt loop. Scanning electron micrographs at the AV shunt vessel lumen showed modified endothelial cells at day 7 and a remarkable number of pores at day 14. The volume of newly formed vessels was increased 12 times from day 5 to day 14. The mechanical factor of shear stress was considered the major stimulator of angiogenesis. This is the first report of electron-microscopic observation of sprouts from a large vessel lumen. The new AV shunt model is useful for basic research on angiogenesis at the large vessels in vivo and, furthermore, could generate vascularised tissues with various cultured cells.

[Adjuvant chemotherapy of premenopausal breast cancer with LH-RH analogue for ovarian protection--a case report]

We report a case in which the LH-RH analogue, goserelin acetate was administered to a 26-year-old female patient diagnosed with premenopausal breast cancer and concurrently receiving anthracycline-based adjuvant chemotherapy for ovarian protection. After radical operation, pathological diagnosis showed that adjuvant chemotherapy was indicated. As she hoped for childbirth, at first goserelin was injected twice and then adjuvant chemotherapy was undergone concurrently with goserelin acetate for ovarian protection. The adjuvant chemotherapy consisted of 4 cycles of every four week intravenous dripinjection of adriamycin 50 mg/m2 and cyclophosphamide 500 mg/m2. The chemotherapy and goserelin acetate were completed at the same time. Menstruation recovered about two months after the finish of adjuvant therapy and was well-regulated after recovery. It is suggested that goserelin combined adjuvant chemotherapy for premenopausal breast cancer may be useful for ovarian protection.

Administration of ANG II induces iron deposition and upregulation of TGF-β1 mRNA in the rat liver

We previously found that ANG II infusion into rats causes iron deposition in the kidney and heart, which may have a role in the regulation of profibrotic gene expression and tissue fibrosis. In the present study, we have investigated whether ANG II can also induce iron accumulation in the liver. Prussian blue staining detected frequent iron deposition in the interstitium of the liver of rats treated with pressor dose ANG II for 7 days, whereas iron deposition was absent in the livers of control rats. Immunohistochemical and histological analyses showed that some iron-positive nonparenchymal cells were positive for ferritin and heme oxygenase-1 (HO-1) protein and TGF-β1 mRNA and were judged to be monocytes/macrophages. It was shown that ANG II infusion caused about a fourfold increase in ferritin and HO-1 protein expression by Western blot analysis and about a twofold increase in TGF-β1 mRNA expression by Northern blot analysis, which were both suppressed by treating ANG II-infused rats with losartan and deferoxamine. In addition, mild interstitial fibrosis was observed in the liver of rats that had been treated with pressor dose ANG II for 7 days or with nonpressor dose ANG II for 30 days, the latter of which also caused loss of hepatocytes and intrahepatic hemorrhage in the liver. Taken together, our data suggest that ANG II infusion induces aberrant iron homeostasis in the liver, which may have a role in the ANG II-induced upregulation of profibrotic gene expression in the liver.

[Study of three-weekly docetaxel and weekly trastuzumab treatment in HER 2-overexpressing metastatic breast cancer patients]

Docetaxel and trastuzumab can be considered to be active drugs for HER 2-overexpressing metastatic breast cancer (MBC). This study was conducted to determine the activity of combination therapy with docetaxel and trastuzumab in MBC patients (pts) by assessing the response rate (RR), time to progression (TTP) and safety. We administered the combination of docetaxel 70 mg/m2 every 3 weeks and trastuzumab using a 4 mg/kg loading dose and thereafter 2 mg/kg weekly. One cycle was three weeks. Between March 2002 and May 2003, 40 pts with HER 2-positive (3+by immunohistochemistry 39, FISH+1) MBC were enrolled in this study, and 39 pts proved eligible. The overall RR was 72% (28/39) [95%CI 55.1%-85.0%], with 6 CR, 22 PR, 7 SD, 1 PD and 3 NE. The median follow-up time was 14.3 months, while the TTP was 6.5 months (range, 0.6-19.8), median OS has not yet been reached. The number of pts assessable for safety was 40. Hematological Grade 3-4 toxicities were leukopenia 87.5% (35/40) and neutropenia 82.5% (33/40). Non-hematological Grade 3 toxicities were weight gain in 2 pts, and anorexia, neuropathy, fever and rash in one pt each. The combination of docetaxel and trastuzumab was a well-tolerated and very active regimen for the treatment of pts with HER 2-overexpressing MBC.

Dimensions of temperament as vulnerability factors in depression

In order to evaluate the hypothesis that one set of genetic risk factors may be common to disorders and dimensions of temperament, whereas environmental risk factors are disorder specific, we have conducted a genetic analysis of dimensions of temperament and symptoms of depression in about 201 pairs of monozygotic and dizygotic twins. Dimensions of temperament associated with novelty seeking, harm avoidance, reward dependence, and persistence were measured by using the Temperament and Character Instruments developed by Cloninger, and depressive symptoms were measured using the Hospital Anxiety and Depression Scale. Differences among individuals on these measures can be explained by differences in their genes and in their environmental experiences. There are no differences between the sexes in gene action affecting temperament. Each dimension of temperament is genetically dependent, and genetic variations in symptoms of depression are largely dependent on the same factors that affect the temperament. Temperament is closely associated with vulnerability to depressive symptoms.

[Combined chemoendocrine therapy using adriamycin, cyclophosphamide and high dose toremifene in patients with recurrent breast cancer]

We studied a new chemoendocrine therapy against recurrent breast cancer in order to evaluate its efficacy and toxicity. Sixteen eligible patients were treated with the therapy consisting of adriamycin/cyclophosphamide (AC) plus toremifene (TOR). Adriamycin (20 mg/m2) was administered intravenously on days 1 and 8, and cyclophosphamide (100 mg/body) was given orally on days 1 to 14 every 4 weeks. TOR (120 mg/day) was given orally daily. The median age of the patients was 52 years; 6 were premenopausal and 10 postmenopausal. As post-operative adjuvant therapy, anthracycline chemotherapy and tamoxifen were given to 4 and 9 patients, respectively. AC therapy was administered for 8.5 cycles (median). Four complete responses (25%), 8 partial responses (37.5%), 4 no change (25%) (including 2 long NC), and 2 progressive disease (12.5%) were obtained, for an overall response rate of 62.5%. The median duration of time to progression and survival were 13.2 months (0.7-30.4 months) and 22.8 months (13.7-44.8 + months), respectively. The frequent toxicities were leukopenia, nausea/vomiting, and alopecia, but these were clinically well tolerated. Our results suggest that the addition of high dose TOR to AC therapy is useful in the treatment of recurrent breast cancer.

D2-lymphadenectomy improves the survival of patients with peritoneal cytology-positive gastric cancer

BACKGROUND

According to the current Japanese Classification of Gastric Cancer, patients with peritoneal cytology-positive (CY1) gastric cancer are classified as stage IV and the curative potential of resection for these patients is regarded as non-curative.

MATERIALS AND METHODS

We compared the clinical outcome of CY1 patients (n=55) with those of patients with other non-curative factors (n=87), to clarify the optimal surgical strategy for CY1 patients.

RESULTS

The 5-year survival rate of CY1 patients was 10.8%, which was significantly better than that observed in the patients with the other non-curative factors. Among CY1 cases, survival outcome of the patients with lymph node metastasis limited to within group 2 was significantly better than the patients with group 3 lymph node metastasis.

CONCLUSION

These results suggested that gastrectomy combined with extended lymphadenectomy should be recommended for patients with gastric cancer who have positive peritoneal cytology as the only non-curative factor.

Striped iron zoning of olivine induced by dislocation creep in deformed peridotites

Deformation of solid materials affects not only their microstructures, but also their microchemistries. Although chemical unmixing of initially homogeneous multicomponent solids is known to occur during deformation by diffusion creep, there has been no report on their chemical zoning due to deformation by dislocation creep, in either natural samples or laboratory experiments. Here we report striped iron zoning of olivine ((Mg,Fe)2SiO4) in deformed peridotites, where the iron concentration increases at subgrain boundaries composed of edge dislocations. We infer that this zoning is probably formed by alignment of edge dislocations dragging a so-called Cottrell 'atmosphere' of solute atoms (iron in this case) into subgrain boundaries during deformation of the olivine by dislocation creep. We have found that the iron zoning does not develop in laboratory experiments of high strain rates where dislocations move too fast to drag the Cottrell atmosphere. This phenomenon might have important implications for the generation of deep-focus earthquakes, as transformation of olivine to high-pressure phases preferentially occurs in high-iron regions, and therefore along subgrain boundaries which would be preferentially aligned in plastically deformed mantle peridotites.

Genetic structure of spatial and verbal working memory

Working memory (WM) encompasses both short-term memory (storage) and executive functions that play an essential role in all forms of cognition. In this study, the genetic structure of storage and executive functions engaged in both a spatial and verbal WM span task is investigated using a twin sample. The sample consists of 143 monozygotic (MZ) and 93 dizygotic (DZ) Japanese twin pairs, ages 16 to 29 years. In 155 (87 MZ, 62 DZ) of these pairs, cognitive ability scores from the Kyodai Japanese IQ test are also obtained. The phenotypic relationship between WM and cognitive ability is confirmed (r = 0.26-0.44). Individual differences in WM storage and executive functions are found to be significantly influenced by genes, with heritability estimates all moderately high (43%-49%), and estimates for cognitive ability comparable to previous studies (65%). A large part of the genetic variance in storage and executive functions in both spatial and verbal modalities is due to a common genetic factor that accounts for 11% to 43% of the variance. In the reduced sample, this common genetic factor accounts for 64% and 26% of the variance in spatial and verbal cognitive ability, respectively. Additional genetic variance in WM (7%-30%) is due to modality specific factors (spatial and verbal) and a storage specific factor that may be particularly important for the verbal modality. None of the variance in cognitive ability is accounted for by the modality and storage genetic factors, suggesting these may be specific to WM.

Four novel withanolide-type steroids from the leaves of Solanum cilistum

Four novel withanolide-type steroids named cilistols p, pm, p1 and u (1-4, respectively), were isolated from the leaves of Solanum cilistum. The respective structures were characterized by spectroscopic means as follows: cilistol p (1) was (22R,24R,25R,26S)-1-oxo-22,26-epoxy-3alpha,5alpha-cycloergostane-6beta,17alpha, 24,25,26-pentaol 26-O-beta-D-glucopyranoside, cilistol pm (2) corresponded to the 6-O-methyl ether derivative of 1; cilistol p1 (3) was represented as the 24-O-methyl ether of 1, and cilistol u (4) was shown to be the epoxide between C-24 and -25, presumably bearing cilistols p, pm and p1 by ring-opening.

Covariance structure of neuroticism and agreeableness: a twin and molecular genetic analysis of the role of the serotonin transporter gene

The Revised NEO Personality Inventory domains of Neuroticism and Agreeableness are considered factorially distinct despite several intercorrelations between these domains. The genetic correlation, an index of the degree to which these intercorrelations are caused by genetic influences, was estimated using data from 913 monozygotic and 562 dizygotic volunteer twin pairs from Canada, Germany, and Japan. The serotonin transporter gene, 5-HTTLPR, was assayed in a sample of 388 nontwin sibling pairs from the United States to determine the contribution of the serotonin transporter locus to the covariation between the Neuroticism and Agreeableness scales. In all four samples, genetic influences contributed to the covariance of Neuroticism and Agreeableness, with the serotonin transporter gene accounting for 10% of the relationship between these domains.

Microvascular and interstitial PO(2) measurements in rat skeletal muscle by phosphorescence quenching

To clarify the transport of O(2) across the microvessels in skeletal muscle, we designed an intravital laser microscope that utilizes a phosphorescence quenching technique to determine both the microvascular and tissue PO(2). After we injected the phosphorescent probe into systemic blood, phosphorescence excited by a N(2)-dye pulse laser was detected with a photomultiplier over a 10 microm in diameter area. In vitro and in vivo calibrations confirmed that the present method is accurate for PO(2) measurements in the range of 7-90 Torr (r = 0.958) and has a rapid response time. This method was then used to measure the PO(2) of microvessels with different diameters (40-130 microm) and of interstitial spaces in rat cremaster muscle. These measurements showed a significant drop in PO(2) in the arterioles after branching (from 74.6 to 46.6 Torr) and the presence of a large PO(2) gradient at the blood-tissue interface of arterioles (15-20 Torr). These findings suggest that capillaries are not the sole source of oxygen supply to surrounding tissue.

Sp1-mediated downregulation of P2X4 receptor gene transcription in endothelial cells exposed to shear stress

Endothelial purinoceptors play an important role in vascular responses to extracellular adenine nucleotides and hemodynamic forces. Here we report that P2X4 purinoceptor expression in human umbilical vein endothelial cells is transcriptionally downregulated by fluid shear stress. When human umbilical vein endothelial cells were subjected to a laminar shear stress of 15 dyn/cm(2), P2X4 mRNA levels began to decrease within 1 h and further decreased with time, reaching 60% at 24 h. Functional analysis of the 1.9-kb P2X4 5'-promoter indicated that a 131-bp segment (-112 to +19 bp relative to the transcription start site) containing a consensus binding site for the Sp1 transcription factor was critical for the shear stress responsiveness. Mutations of the Sp1 site decreased the basal level of transcription and abolished the response of the P2X4 promoter to shear stress. Electrophoretic mobility shift assays showed a marked decrease in binding of Sp1 to the Sp1 consensus element in shear-stressed cells, suggesting that Sp1 mediates the shear stress-induced downregulation of P2X4 gene transcription.

Upregulatory Expression of Furin and Transforming Growth Factor-β by Fluid Shear Stress in Vascular Endothelial Cells

Abstract —Furin, a yeast Kex2-family endoprotease, converts many vasoregulatory propeptides, including pro-transforming growth factor (TGF)-β to their mature forms. We examined whether furin expression is regulated by shear stress in vivo and in vitro. When an arteriovenous shunt was placed between the carotid artery and external jugular vein in rabbits, furin and TGF-β were highly expressed in shear stress–loaded endothelial cells. Exposure of bovine aortic endothelial cells in culture to shear stress induced furin and TGF-β expression in a similar manner. Molecular analysis of furin expression in bovine aortic endothelial cells revealed that shear stress increases the furin gene expression at transcriptional levels. Furthermore, TGF-β itself increased the furin mRNA levels. Shear-mediated furin expression was partly mediated by TGF-β because shear-induced furin mRNA levels were considerably decreased by overexpression of the truncated form of the TGF-β type II receptor. Likewise, blockade of furin activity by a furin inhibitor significantly decreased the endothelial production of mature TGF-β. Taken together, the results indicate that furin expression is induced and maintained by a coordination of shear stress and TGF-β. Increased furin expression may facilitate the formation of mature TGF-β, resulting in the enhanced effects of TGF-β on endothelial cells and vascular smooth muscle cells in the vasculature.

Time-dependent promotion activity of 17beta-estradiol on uterine carcinogenesis in mice initiated with N-ethyl-N-nitrosourea

The time-dependent promotion activity of 17beta-estradiol (E2) by initiation with N-ethyl-N-nitrosourea (ENU) on induction of mouse uterine endometrial proliferative lesions was examined. Illumination-induced persistent estrous female CD-1 mice were divided into five groups at 9 weeks of age. At 10 weeks of age, mice in all groups (n=25) were given a single intra-uterine administration of ENU (50 mg/kg), dissolved in polyethylene glycol. Animals in Groups 2 to 5 were then implanted s.c. with an E2 pellet at 9, 11, 14 and 17 weeks of age. The implants were left in place for 8 weeks and then taken out. At the termination of the experiment (week 15 after the ENU-treatment), all surviving mice were killed and the development of uterine proliferative lesions were assessed. All groups demonstrated endometrial hyperplasias and adenocarcinomas and the incidences of the latter in ENU plus E2 treated animals (Groups 2 to 5; 36, 48, 35 and 36%, respectively) were significantly higher compared to 8% for Group 1, without any variation with the age at E2 treatment. However, the incidences of adenocarcinomas plus severe hyperplasias increased from Groups 1 to 5 (28, 40, 56; P<0.05, 61; P<0.05 and 80%; P<0.01, respectively), indicating that promotion effects of E2 on induction of uterine proliferative lesions in the uterine endometrium become more pronounced with the interval after ENU initiation.

MRNA expression on shape-engineered endothelial cells: adhesion molecules ICAM-1 and VCAM-1

This study was designed to assess the effect of cell shape on mRNA expression of two adhesion molecules, intracellular adhesion molecule-1 and vascular adhesion molecule-1, on endothelial cells. Photo-microprocessing using photoreactive poly(ethylene glycol) produced two different patterned-cell adhesive regions on tissue culture dishes: one is a striped region on which adhered cells are highly elongated and aligned along the long axis of the striped pattern, and the other is a circular region on which cells are less spread out and rounded. mRNA expressions, measured by the reverse transcription-polymerase chain reaction technique, revealed higher mRNA expression for intracellular adhesion molecule-1 and lower mRNA expression for vascular adhesion molecule-1 on elongated cells than those on round cells. This indicates that surface-induced cell shape induces changes in the mRNA expression of these molecules. The significance of cell-shape-induced mRNA expression is discussed in conjunction with the experimental results of flow-induced expression at molecular and mRNA levels.

Genetics of cognition: outline of a collaborative twin study

A multidisciplinary collaborative study examining cognition in a large sample of twins is outlined. A common experimental protocol and design is used in The Netherlands, Australia and Japan to measure cognitive ability using traditional IQ measures (i.e., psychometric IQ), processing speed (e.g., reaction time [RT] and inspection time [IT]), and working memory (e.g., spatial span, delayed response [DR] performance). The main aim is to investigate the genetic covariation among these cognitive phenotypes in order to use the correlated biological markers in future linkage and association analyses to detect quantitative-trait loci (QTLs). We outline the study and methodology, and report results from our preliminary analyses that examines the heritability of processing speed and working memory indices, and their phenotypic correlation with IQ. Heritability of Full Scale IQ was 87% in the Netherlands, 83% in Australia, and 71% in Japan. Heritability estimates for processing speed and working memory indices ranged from 33-64%. Associations of IQ with RT and IT (-0.28 to -0.36) replicated previous findings with those of higher cognitive ability showing faster speed of processing. Similarly, significant correlations were indicated between IQ and the spatial span working memory task (storage [0.31], executive processing [0.37]) and the DR working memory task (0.25), with those of higher cognitive ability showing better memory performance. These analyses establish the heritability of the processing speed and working memory measures to be used in our collaborative twin study of cognition, and support the findings that individual differences in processing speed and working memory may underlie individual differences in psychometric IQ.

Six new withanolide-type steroids from the leaves of Solanum cilistum

Six new withanolide-type steroids, designated cilistols v, t, i, j, y and w (1-6, respectively), were obtained from the leaves of Solanum cilistum. Their respective structures were characterized by spectroscopic means as follows: Cilistol v (1) was (22R,24Z)-1alpha,3beta,22,26-tetrahydroxyergost-5,24-diene 26-O-beta-D-glucopyranoside, which is regarded as the precursor of other withanolide-type steroids included in this title plant. Cilistol t (2) was (22R,24S,25R,26S)-24,25;22,26-diepoxy-1alpha,3beta,26-trihydroxyergost-5-ene 26-O-beta-D-glucopyranoside, and cilistols j (3) and i (4) corresponded to the substances probably formed by the cleavage of the epoxy ring at C-24 and 25 of 2. Cilistol y (5) was 3-O-sulphonyl (22R,24S,25R,26R)-1-oxo-24,25; 22,26-diepoxy-3beta,17alpha,26-trihydroxyergost-5-ene 26-O-beta-D-glucopyranoside, and cilistol w (6) corresponded to the substance obtained by the fission of the epoxy ring at C-24 and 25 of 5. The occurrence of these withanolide type steroids from Solanum genera is rare and worthy of note.

Genetic structure of the five-factor model of personality in a Japanese twin population

Dimensional approaches have been used to describe the fundamental dimensions that underlie the entire domain of normal and pathological personality. We tested the five factor model of personality structure in a sample of Japanese twins, to clarify the contributions of genetic and environment. The revised NEO personality inventory (NEO-PI-R) was administered to 251 twin pairs, ranging in age from 15 to 27 years of age. The NEO-PI-R is a 240-item questionnaire which was developed to assess the dimensions of personality. Univariate genetic analysis showed that the AE model in which phenotypic covariances are explained only by additive genetic (A) and nonshared environment (E) is still a plausible model, and that the relative proportion of genetic influence was comparable to that reported by Loehlin (1992). Multivariate genetic analysis of the Japanese data suggested/revealed that the five factors are genetically dependent on each other and one common genetic factor mediates their interdependence. Previous studies have assumed that they are phenotypically independent and robust. Although there are sampling biases in the present study, it is noteworthy that the results for all five factors depicted by the NEO-PI-R were comparable to those reported by Western researchers, and the genetic structure of the five-factor model is complex.

Fluid shear stress activates Ca(2+) influx into human endothelial cells via P2X4 purinoceptors

Ca(2+) signaling plays an important role in endothelial cell (EC) responses to shear stress generated by blood flow. Our previous studies demonstrated that bovine fetal aortic ECs showed a shear stress-dependent Ca(2+) influx when exposed to flow in the presence of extracellular ATP. However, the molecular mechanisms of this process, including the ion channels responsible for the Ca(2+) response, have not been clarified. Here, we demonstrate that P2X4 purinoceptors, a subtype of ATP-operated cation channels, are involved in the shear stress-mediated Ca(2+) influx. Human umbilical vein ECs loaded with the Ca(2+) indicator Indo-1/AM were exposed to laminar flow of Hanks' balanced salt solution at various concentrations of ATP, and changes in [Ca(2+)](i) were monitored with confocal laser scanning microscopy. A stepwise increase in shear stress elicited a corresponding stepwise increase in [Ca(2+)](i) at 250 nmol/L ATP. The shear stress-dependent increase in [Ca(2+)](i) was not affected by phospholipase C inhibitor (U-73122) but disappeared after the chelation of extracellular Ca(2+) with EGTA, indicating that the Ca(2+) increase was due to Ca(2+) influx. Antisense oligonucleotides designed to knockout P2X4 expression abolished the shear stress-dependent Ca(2+) influx seen at 250 nmol/L ATP in human umbilical vein ECs. Human embryonic kidney 293 cells showed no Ca(2+) response to flow at 2 micromol/L ATP, but when transfected with P2X4 cDNA, they began to express P2X4 purinoceptors and to show shear stress-dependent Ca(2+) influx. P2X4 purinoceptors may have a "shear-transducer" property through which shear stress is perceived directly or indirectly and transmitted into the cell interior via Ca(2+) signaling.

Possible mechanisms underlying mammary carcinogenesis in female Wistar rats by nitrofurazone

Mechanisms underlying mammary carcinogenesis in female rat given nitrofurazone (NF) were examined. Experiment I: female Wistar rats were divided into three groups, and given diets containing 0, 500 or 1000 ppm NF for 5 weeks. At terminal sacrifice, body and uterus weights were the same in all groups, although ovary weights in NF-treated animals were significantly higher than in control animals, the increase being dose-dependent. Serum prolactin (PRL) concentrations in NF-treated groups at 17:00 h on the day of proestrus were also dose-dependently higher than that in control group. Experiment II: a two-stage rat mammary carcinogenesis protocol was performed. Rats were divided into four groups, Groups 2 and 4 being treated by 9,10-dimethyl-1,2-benzanthracene (DMBA) at 7-weeks-old. Groups 3 and 4 were given diets containing 1000 ppm of NF between 8 and 27 weeks of age, when all surviving rats were autopsied. DMBA-treated animals demonstrated mammary tumors at high incidences, 91.1 and 90.5%, respectively, in Groups 2 and 4, no tumor development being observed without the initial carcinogen exposure (Groups 1 and 3). The mean tumor weights and the mean numbers of tumors per tumor-bearing rats in Group 4 were increased as compared with Group 2, albeit not significantly. Serum PRL (proestrus day at 17:00 h) and progesterone (PG) (diestrus day at 10:00 h) concentrations in NF-treated animals (Groups 3 and 4) were significantly higher than those in untreated rats (Groups 1 and 2). These results suggest that increases of serum PRL and PG concentrations by NF may be the most important factors regarding its promotion of mammary tumor growth and/or enhancement of mammary carcinogenesis in female rats.

Subcutaneous treatment of p-tert-octylphenol exerts estrogenic activity on the female reproductive tract in normal cycling rats of two different strains

Effects of p-tert-octylphenol (OP), an endocrine disrupting chemical (EDC), on the female reproductive tract of normal cycling Fischer 344 (F344) and Donryu rats were investigated. OP was subcutaneously injected at concentrations of 12.5, 25, 50 or 100 mg/kg for 28 days. The most notable changes were the disappearance of normal cyclicity in the 50 mg/kg or more OP-treated groups of both the strains, and the appearance of persistent estrus (PE) evident on examination of vaginal smears in the 100 mg/kg groups of both the strains, the effects being time- and dose-dependent. In PE rats of both the strains, the uterine morphology deviated from the normal for each estrous stage of the cycling rats, and proliferation in the endometrium was slightly increased. The data for uterine weights, luminal epithelial cell-heights and/or numbers of epithelial cells in the endometrium demonstrated equivocal alteration. In both the strains, the serum 17beta-estradiol (E2) levels were decreased with 50 mg/kg of OP or more. Serum concentrations of the administrated chemical were dose and duration-dependently increased in all the treated groups of both the strains. The results demonstrate that subcutaneous administration of OP at doses of 50 mg/kg or more exerts time- and dose-dependent estrogenic activity on the reproductive tract of normal cycling female Donryu and F344 rats, indicating similar qualitative sensitivity to the effects in both the strains. Vaginal cytology may be the most sensitive endpoint for the detection of estrogenic activity of potential EDCs using adult cycling rats.

[Randomized comparative study of CMF (cyclophosphamide, methotrexate and 5-fluorouracil) and UFT-tamoxifen regimens as adjuvant chemotherapy after surgery for breast cancer: Tochigi Prefectural Study Group for Post-Breast Cancer Adjuvant Chemotherapy]

This prospective randomized study aimed at establishing the optimal postoperative adjuvant chemotherapy regimen for premenopausal n+ breast cancer patients. The treatments were Regimen A, comprising 6 courses of CMF (cyclophosphamide, 100 mg/body on days 1-14; methotrexate, 40 mg/m2 on days 1 and 8; and 5-fluorouracil, 500 mg/m2 on days 1 and 8), and Regimen B, consisting of UFT (300 mg/day) and tamoxifen (30 mg/day) administered orally each day for 2 years. Telephone registration allocated the patients to the treatment groups by the minimization method in relation to the T category, number of n+ lesions and estrogen receptor status. Forty-five patients were registered, and 44 of them were eligible (22 cases each to Regimen A and Regimen B). The principal background factors showed no biases between the groups. The adverse reaction incidence was significantly higher with Regimen A (90.9% vs 22.7%). The 5-year survival rate was 89.8% with Regimen A and 100% with Regimen B, while the 5-year disease-free rates were 64.5% and 76.3%, showing no statistical significance. Regimen B showed a better QOL rating after 6 months of therapy in relation to nausea-vomiting and hair loss, and after 24 months in relation to appetite, sleep, performance status, happiness, anorexia and hair loss.

P2X(4) receptors mediate ATP-induced calcium influx in human vascular endothelial cells

ATP induces Ca(2+) influx across the cell membrane and activates release from intracellular Ca(2+) pools in vascular endothelial cells (ECs). Ca(2+) signaling leads to the modification of a variety of EC functions, including the production of vasoactive substances such as nitric oxide and prostacyclin. However, the molecular mechanisms for ATP-induced Ca(2+) influx in ECs have not been thoroughly clarified. Here we demonstrate evidence that a P2X(4) receptor for an ATP-gated cation channel is predominantly expressed in human ECs and is involved in the ATP-induced Ca(2+) influx. Northern blot analysis distinctly showed the expression of P2X(4) mRNA in human ECs cultured from the umbilical vein, aorta, pulmonary artery, and skin microvessels. Competitive PCR revealed that P2X(4) mRNA expression was much higher in ECs than was the expression of other subtypes, including P2X(1), P2X(3), P2X(5), and P2X(7). Treatment of ECs with antisense oligonucleotides designed to target the P2X(4) receptor decreased the P2X(4) mRNA and protein levels to approximately 25% of control levels and markedly prevented the ATP-induced Ca(2+) influx.

Anti-herpes virus activity of Solanum steroidal glycosides

Since some Solanum-genus plants have traditionally been used for anti-cancer and anti-herpes agents from olden times, we examined anti-herpes simplex virus type 1 (HSV-1) activity of typical steroidal glycosides with the frameworks of spirostane (including nuatigenin glycoside), furostane, solasodane, tomatidane and ergostane (including dimer) obtained from Solanum plants. Among these steroidal glycosides, the spirostanol glycosides were most effective. An inclination was observed for the potency of activity to decrease in the order of spirostane, tomatidane, ergostane, solasodane, nuatigenin type, dimer of ergostane and furostane. It was also suggested that the activity depends on the kind of oligosacchride moiety.

Dose- and treatment duration-related effects of p-tert-octylphenol on female rats

We conducted a study to investigate the relation between estrogenic effects of p-tert-octylphenol (OP) and serum concentration as well as treatment duration. Adult ovariectomized rats were given daily subcutaneous injections of OP for 2 and 14 days. 17beta-Estradiol was also administrated at a dose of 5 microg/kg. OP was detected in serum at doses of 25 mg/kg and above for 2 days and with multiple doses (14 days) of 12.5 mg/kg. Uterine weights and luminal epithelial height were increased although the effects were weak compared to 17beta-estradiol. Estrous conversion of the vaginal smear was detected only in 14-day-treated animals. OP-treatment for 2 days caused a dose-related increase in proliferation of uterine luminal, glandular, and stromal cells and vaginal epithelial cells. From the 14-day experiment, the minimum estrogenic dose level of OP was concluded to be 25 mg/kg/day and the serum level at the dose was determined to be about 80 ng/ml. These findings demonstrated that OP exerts estrogenic activity in the female reproductive tract of ovariectomized rats only at high levels of exposure and that the effects are fundamentally related to serum OP levels.

Amino acid sequence studies on cytolytic toxins from sea anemone Heteractis magnifica, Entacmaea quadricolor and Stichodactyla mertensii (Anthozoa)

The complete amino acid sequence of a cytolytic toxin, HmT, isolated from sea anemone Heteractis magnifica was determined. It is composed of 177 amino acid residues and lacks half-cystines. Partial N-terminal sequences of three other cytolysins from Entacmaea quadricolor (EnT) and Stichodactyla mertensii (SmT-1 and SmT-2) were also determined. Comparing these sequences with those of other sea anemone cytolysins, a high degree of homology was observed.

Correlation of cyclin D1 MRNA levels with clinico-pathological parameters and clinical outcome in human breast carcinomas

In order to evaluate the prognostic significance of cyclin D1 mRNA expression in mammary neoplasia, its levels were measured in 97 breast cancers by reverse transcription-polymerase chain reaction (PCR) using fluorescent primer and standard RNA along with estrogen receptor (ER). The median value of cyclin D1 mRNA was 1.60 amol/microg RNA (range, 0.01 to 5.63 amol/microg RNA). ER mRNA was detectable in 70 breast cancer samples (72.2%) and cyclin D1 mRNA levels were significantly higher in ER mRNA-positive than in ER mRNA-negative tumors (p = 0.009). Furthermore, cyclin D1 mRNA levels were significantly (p = 0.001) lower in patients who experienced a recurrence during the follow-up period (mean of 40.8 months, median of 39 months) compared with those with no evidence of recurrent disease (mean of 49.2 months, median of 48 months), and in those who died from disease (mean follow-up period of 30.5 months, median of 26 months) than in the survivors (mean of 50.5 months and median of 48 months) (p = 0.005). Setting the median value (= 1.60 amol/microg RNA) as the cutoff point, expression was significantly associated with relapse-free survival (p = 0.002). Similarly, a significant correlation was observed between the cyclin D1 mRNA level and overall survival (p = 0.015). The expression was found to be an independent factor for predicting relapse-free survival using multivariate analysis.