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BACKGROUND AND PURPOSE: Metal artifacts reduce the quality of CT images and increase the difficulty of interpretation. This study compared the ability of model-based iterative reconstruction and hybrid iterative reconstruction to improve CT image quality in patients with metallic dental artifacts when both techniques were combined with a metal artifact reduction algorithm. MATERIALS AND METHODS: This retrospective clinical study included 40 patients (men, 31; women, 9; mean age, 62.9 ± 12.3 years) with oral and oropharyngeal cancer who had metallic dental fillings or implants and underwent contrast-enhanced ultra-high-resolution CT of the neck. Axial CT images were reconstructed using hybrid iterative reconstruction and model-based iterative reconstruction, and the metal artifact reduction algorithm was applied to all images. Finally, hybrid iterative reconstruction + metal artifact reduction algorithms and model-based iterative reconstruction + metal artifact reduction algorithm data were obtained. In the quantitative analysis, SDs were measured in ROIs over the apex of the tongue (metal artifacts) and nuchal muscle (no metal artifacts) and were used to calculate the metal artifact indexes. In a qualitative analysis, 3 radiologists blinded to the patients’ conditions assessed the image-quality scores of metal artifact reduction and structural depictions. RESULTS: Hybrid iterative reconstruction + metal artifact reduction algorithms and model-based iterative reconstruction + metal artifact reduction algorithms yielded significantly different metal artifact indexes of 82.2 and 73.6, respectively (95% CI, 2.6–14.7; P < .01). The latter algorithms resulted in significant reduction in metal artifacts and significantly improved structural depictions(P < .01). CONCLUSIONS: Model-based iterative reconstruction + metal artifact reduction algorithms significantly reduced the artifacts and improved the image quality of structural depictions on neck CT images.

[(AlN)1/(GaN)n1]m/(AlN)n2 quantum-cascade (QC) structures were prepared by hot wall epitaxy for midinfrared laser application, periodically inserting several atomiclayers of AlN into (AlN)1/(GaN)n1 short period superlattices. The (AlN)1/(GaN)n1 short-period superlattice has a large first-subband broadening, and effective population inversion between first and second subbands is expected through the electron injection into the second subband. The AlN/GaN quantum-well system grown to [0001] direction shows a large piezo-electric effect, and the effective electron injection into the second subband is expected by the periodically inserted AlN layers. The QC structure was characterized by X-ray diffraction, transmission electron microscopy (TEM). The (0002) X-ray diffraction pattern showed good agreement with the theoretical one, and (10—14) reciprocal mapping of the cascade structure showed the QC structure was grown coherently on the GaN buffer layer.

Nuclear receptors (NRs) regulate transcription in a ligand-dependent way through two types of coactivator complexes: the p160/CBP histone acetyl transferase (HAT) complex and the DRIP/TRAP/SMCC complex without HAT activity. Here we identified a large human (h) coactivator complex necessary for the estrogen receptor alpha (ERalpha) transactivation. This complex contains the GCN5 HAT, the c-Myc interacting protein TRRAP/PAF400, TAF(II)30, and other subunits. Similarly to known TFTC (TBP-free TAF(II)-containing)-type HAT complexes (hTFTC, hPCAF, and hSTAGA), TRRP directly interacted with liganded ER alpha, or other NRs. ER alpha transactivation was enhanced by the purified complex in vitro. Antisense TRRAP RNA inhibited estrogen-dependent cell growth of breast cancer cells. Thus, the isolated TFTC-type HAT complex acts as a third class of coactivator complex for NR function.

(Molecular Cell 9, 553–562; March 2002)Recently, we were made aware that images in Figures 1B, 2F, and 3E were inappropriately manipulated such that they did not reflect the actual experimental data they claimed to represent. The experiments and figure preparation were done in the nuclear signaling laboratory in the IMCB. Because of the data handling issues, we wish to retract this paper and to sincerely apologize to the scientific community for any potential harm we may have caused.

We measured cerebral blood flow, oxygen metabolism, glucose utilization, and dopamine metabolism in the brain of a patient with corticobasal degeneration using positron emission tomography (PET). The clinical picture is distinctive, comprising features referable to both cortical and basal ganglionic dysfunction. Brain imagings of glucose and dopamine metabolism can demonstrate greater abnormalities in the cerebral cortex and in the striatum contralateral to the more affected side than those of blood flow and oxygen metabolism. This unique combination study measuring both cerebral glucose utilization and dopamine metabolism in the nigrostriatal system can provide efficient information about the dysfunctions which are correlated with individual clinical symptoms, and this study is essential to diagnosis of corticobasal degeneration.

We studied the chronic effect of thyrotropin releasing hormone (TRH) in a patient with spinocerebellar degeneration by measuring cerebral metabolic rate for glucose (CMRG1c) using 2-[18F]fluoro-2-deoxy-D-glucose (18FDG) and positron emission tomography (PET). A 56-year-old female, who had suffered from progressive ataxia for 2 years, was treated by intravenous administration of 2 mg TRH for 3 weeks, and CMRG1c of the brain was measured before and after treatment. CMRG1c was markedly decreased in the cerebellum and there was no significant difference before and after the treatment, i.e. mean CMRG1c values were 4.92 and 4.90 mg/100 g/min, and the ratios of the cerebellum versus the frontal cortex were 0.50 and 0.51, respectively. The degree of disequilibrium of her body examined with stabilography became better by the 19th day and further improved by the 26th day after the start of TRH treatment. Based on the present study we conclude that long-term administration of TRH did not improve CMRG1c in the cerebellum, but evidently improved the sway of gravity center by stabilography. We speculate that the chronic effect of TRH was not necessarily due to an improvement of cerebellar function, because TRH receptors are widely distributed throughout the central nervous system.

This article examines the adoption of behaviors of the teen drug and delinquent subcultures among Asian Pacific youth within the framework of the theory of segmented assimilation. Alejandro Portes ...

This study uses data from the Asian Student Drug Survey to examine the extent to which social control and peer cluster theories explain drug and alcohol use among students of various Asian American subgroups. The data suggest that drug and alcohol use differs significantly among the various subgroups. Pacific Islander and Filipino American youths have the highest rates, whereas Chinese American youths have the lowest rates of use. Among some ethnic groups, families, friends, and teachers are unable to keep youths from using drugs and alcohol. Even so, families play an important role for Chinese and Asian Indians, and teachers are important in keeping Southeast Asians from drug and alcohol use. Commitment to school and to high moral standards also insulates youths from drug and alcohol use. Contrary to social control theory, however, use of drugs and alcohol by peers strongly affects alcohol and drug use. The data suggest that youths of all ethnic groups tend to use drugs and alcohol when their peers have tried marijuana, have gotten drunk, have been gang members, or have encouraged marijuana use. In general, the data are consistent with social control theory, with the exception of peer influence on drug and alcohol use as predicted by peer cluster theory.

La radiosensibilite des fibroblastes diploides humains est liee a l'expression de p53, et a la perte de cellules en cycle resultant d'un arret irreversible en phase G 1 ; dans les cellules n'ayant pas une fonction p53 normale, on ne constate aucun arret, et elles sont plus radio-resistantes. Dans des conditions favorables a la reparation de lesions potentiellement lethales dues a l'irradiation, la proportion de cellules bloquees en phase G 1 baisse, et les chances de survie sont accrues. Bien differente est la reaction des cellules cancereuses humaines. Le blocage par irradiation en phase G 1 est minime ou inexistant dans les cellules cancereuses p53+, et la perte de la fonction normale p53 n'a pas d'effet constant sur leur radiosensibilite. Ces resultats laissent penser que l'expression de p53 n'est pas un indice fiable permettant de prevoir la reaction des tumeurs solides a la radiotherapie.

Although an abundance of anecdotal and journalistic articles about Asian Americans as a model minority has appeared in the past two decades, a review of the literature revealed surprisingly few empirical studies on this subject. Specifically, no research has been done on whether Asian Americans perceive themselves as a model minority and how they are perceived by other racial groups. In this paper, the results of a sample survey of a large public land-grant university on Asian Americans' self-perceptions and other racial groups' perceptions of Asian Americans in terms of their preparedness for college, motivation, and expectations of future career success are reported. Using whites as a comparison group, it was found that Asian Americans perceived themselves as more prepared, motivated and more likely to have greater career success than whites. Also, the perceptions that Asian Americans were superior to whites in those three areas were shared by whites, African Americans, Hispanics, and Native Americans. In contrast, the other three minority groups each viewed itself as inferior to whites in each of the three areas measured, and were so viewed by the other racial groups as well. The implications of these findings are explored.

In order to investigate the spin state of azurite, Cu3(CO3)2(OH)2, we have measured the thermal conductivity along the c-axis, $\kappa$c, perpendicular to the spin diamond-chains. It has been found that the temperature dependence of $\kappa$c shows a broad peak at ~ 100 K, which is explained as being due to the strong phonon-scattering by the strong spin-fluctuation owing to the spin frustration at low temperatures below ~ 100 K. Furthermore, it has been found that the temperature dependence of $\kappa$c shows another peak at low temperatures below 20 K and that $\kappa$c is suppressed by the application of magnetic field along the c-axis at low temperatures below ~ 35 K. In high magnetic fields above ~ 8 T at low temperatures below ~ 6 K, it has been found that $\kappa$c increases with increasing field. The present results have indicated that both spin-singlet dimers with a spin gap of ~ 35 K and antiferromagnetically correlated spin-chains with the antiferromagnetic exchange interaction of ~ 5.4 K are formed at low temperatures, which is consistent with the recent conclusion by Jeschke et al. [Phys. Rev. Lett. 106, 217201 (2011)] that the ground state of spins in azurite in zero field is a spin-fluid one. In addition, a new quantum critical line in magnetic fields at temperatures above 3 K has been proposed to exist., Comment: 12 pages, 4 figures, accepted for publication in Journal of the Physical Society of Japan

Isologous anterior pituitary grafting, 4 each, to 3-4-month-old SHN and SLN male mice resulted in an appearance of mammary tumours from 8 months of age and the incidence at 12 months reached 53·8% in each strain. All tumours were diagnosed as type B adenocarcinomas. In association with the results, normal mammary gland growth and mouse mammary tumour virus (MMTV)-gp52 antigen levels in the submaxillary glands were stimulated by the treatment in these strains. The effect of pituitary grafting was much less in GR/A male mice in which no mammary tumours appeared.

A homogeneous distribution of SiO2 precipitates in Czochralski-grown silicon containing different amounts of oxygen were produced by annealing the dislocation-free crystals at 1023 K. The resulting long-range strain field modifies the integrated reflecting power R of the Bragg reflections measured on an absolute scale with 316 keV γ-radiation. The thickness dependence of R has been modelled using the results of statistical dynamical theory. The assumption made in Kato's original theory, where the correlation length Γ for the wave-field amplitudes is proportional to the extinction length, has to be abandoned. Recent modifications to statistical dynamical theory by Becker & Al Haddad [Acta Cryst. (1990). A46, 123–139] lead to excellent agreement with the present experimental results. Furthermore, in the present case, the correlation length τ, describing short-range correlation in the fluctuations of the phase factor caused by the displacement field of the defects, turns out to be very small, so that the contribution of the mixed term to the integrated reflecting power could be neglected. Therefore, the defect scattering is characterized by the static Debye–Waller factor alone, which was determined accurately from the thickness dependence of the measured integrated reflecting power. From the ratio of the static Debye–Waller factors determined for different orders of reflection, the sizes of the SiO2 precipitates have been calculated and the results are in very good agreement with the values determined directly from small-angle neutron scattering on the same samples.

A theoretical explanation of fashion change is offered, drawing upon symbolic-interactionist insights on fashion and appearance, and developing macro-micro connections between cultural ambivalence and the negotiation of meaning as inspired by symbolic ambiguity in appearances. The postmodern condition, connected with advanced capitalism, spawns cultural ambivalence and a plethora of clothing styles that emerge, in part, to clarify and lend expression to ambivalence. A broad variety of clothing styles, however, coupled with tendencies toward production of self, contribute to a high degree of ambiguity in individually constructed appearances, the meaning of which must then be collectively negotiated in social interaction. Failure of clothing styles to resolve cultural ambivalence results in fashion change in an ongoing dialectic.

Four medial neurosecretory cells (MNC) and 4 lateral neurosecretory cells (LNC) in each brain hemisphere, and one pair of cells in each thoracic ganglion (TG) of Galleria larva react with antibodies against bombyxin and insulin. Material secreted from the MNC and LNC is released mainly in the corpora allata, and that from the TG through the ventral median nerves. Intrinsic secretory cells of the corpora cardiaca (CC) also contain bombyxin-like, but not insulin-like material. The immunoreactivities all disappear during molts and reappear with resumption of feeding. In the MNC and TG they reappear for less than a day, but in cells of the CC immunoreactivity reappears for the whole feeding period. Before pupation, the LNC become temporarily immunopositive towards the end of feeding period, and the MNC and TG during the wandering period, i.e. at the time of prothoracic gland stimulation. Immunoreactivity disappears during the pupal molt. In pupae it is present in the 4 pairs of MNC and 1–2 pairs of LNC 12–48 hr after ecdysis, and in cells of the CC from 12 hr after ecdysis until the end of the pupal instar. In adult, immunoreactivity is restricted to 2 pairs of the LNC and to CC cells.

β-Pb 0,333 V 2 O 5 cristallise dans C2/m avec a=15,463, b=3,6477, c=10,116 A, β=109,20 o , Z=6; affinement jusqu'a R=0,054. La structure est du meme type que celle de β-Na x V 2 O 5 . Du fait du desordre monodimensionnel des chaines decalees d'ions Pb le long de [010], des reflexions du sous-reseau apparaissant a h/2, k+1/2, l sont attachees par des raies de diffusion en diffraction paralleles a a

The effects of chronic free access to caffeine (0.01% or 0.05%) in drinking water and subsequent withdrawal on spontaneous motor activity for 24 hours and some related parameters were examined in 8-week-old male and female ICR mice. In the males, the 0.01% group showed little response, but in the 0.05% group the activities in both light- and dark-phases and, consequently, in total increased and peaked on day 5 of treatment. The response gradually decreased on days 15 and 30 and reached the control level after 30 days of caffeine withdrawal. Meanwhile, in the females, the activity was stimulated by both 0.01% and 0.05% of caffeine, at the dark- and light-phases in the former and latter, respectively. The response peaked at 30 days and decreased near to the control level thereafter in both groups. Caffeine affected little the food intake; however, water intakes were higher and lower than the control in the 0.05% and 0.01% male groups, respectively, but the opposite was true in the females. Plasma component levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), cholesterol and glucose were higher than the control in the males and females treated with 0.05% of caffeine. The caffeine had little effect on the body weight change, organ weights and external appearance throughout the experiment. Thus, the sex- and dose-related differences in the responses to caffeine of spontaneous motor activity and related parameters were proved under physiological conditions.

To investigate the role of gonadal hormones in spontaneous motor activity and the contribution of Sasa Health, bamboo grass leaf extract, to this process, female and male ICR mice were gonadectomized at 2 (Experiment I) or 9-12 months of age (Experiment II). The spontaneous motor activity was measured 1 week and 1 month after the operation, then after a subsequent 1 month of treatment with Sasa Health administered in the drinking water. Ovariectomy caused a significant decrease in activity even after 1 week in Experiment I, but had little effect in Experiment II. In the males, a significant decrease was found only in the dark phase 1 month after castration in Experiment I, while little change in activity was induced by castration in Experiment II. Administration of Sasa Health caused an increase and decrease in the activity of the females and males, respectively, of both the control and the gonadectomized groups in Experiment I. Sasa Health had little effect on the motor activity in Experiment II. The agent acted on the plasma levels of several components modulated by gonadectomy, mostly restoring them to the control values. These findings indicate that gonadal hormones and Sasa Health influence spontaneous motor activity and plasma component levels in both sexes and have apparent sex- and age-related effects.

We have measured temperature and magnetic-field dependences of the thermal conductivity of single crystals of the frustrated two-leg spin-ladder system BiCu2PO6 in magnetic fields up to 14 T. It has been found that the temperature dependence of the thermal conductivity along every principal crystallographic axis shows two peaks in zero field but that the magnitude of the thermal conductivity along the b-axis parallel to spin ladders, $\kappa$b, is significantly larger than those of the thermal conductivity along the a-axis, $\kappa$a, and along the c-axis, $\kappa$c, at high temperatures above 7 K. These results suggest that the thermal conductivity due to spins probably exists only in $\kappa$b. Furthermore, it has been found that both magnetic-field dependences of $\kappa$a and $\kappa$b at 3 K show kinks at ~ 7 T and ~ 10 T, where the spin state may change., Comment: 4 pages, 2 figures

We have measured the thermal conductivity in the ab-plane, $\kappa$ab, and along the c-axis, $\kappa$c, of single crystals of the S = 1/2 triangular-lattice antiferromagnet Ba3CoSb2O9 in zero field and magnetic fields. In zero field, it has been found that both $\kappa$ab and $\kappa$c show a similar broad peak around 40 K, suggesting that the thermal conductivity due to phonons is dominant in this compound and that the mean free path of phonons is suppressed so much by strong magnetic-fluctuations due to the magnetic frustration. It has also been found that both $\kappa$ab and $\kappa$c show a kink at the antiferromagnetic transition temperature TN. In magnetic fields parallel to the ab-plane up to 14 T, magnetic-field dependences of both $\kappa$ab and $\kappa$c at temperatures below and above TN have been found to be understood taking into account the phonon-magnon scattering in the so-called 120${\deg}$ structure phase and the up-up-down (UUD) phase, while the minima of $\kappa$ab and $\kappa$c observed in the middle of the UUD phase have not been understood. This suggests the occurrence of some change of the magnetic state in the middle of the UUD phase., Comment: 5 pages, 3 figures

The effects on spontaneous motor activity of the pattern of restricted feeding, far-infrared ray (FIR) irradiation or free access in drinking water containing Sasa Health, a bamboo grass leafextract, were examined in SHN male mice at 2-3 months of age. In mice whose diet was restricted to 60% of the control, fed at 9:00 or 17:00 hours, the level of spontaneous behaviour was elevated 1 hour before the respective feeding time (8:00 or 16:00 hours). The activity was stimulated by FIR in both the control and food-restricted mice, but to a much higher degree in the latter. Treatment with Sasa Health in drinking water lowered the elevated activity level in food-restricted mice. Plasma component levels and organ weights were modulated by FIR or Sasa Health. The findings revealed that, not only the restricted feeding itsel, but also its pattern, significantly affected behaviour and that FIR and Sasa Health modified the deleterious effects of restricted feeding.

Like most characteristics studied in research, mammary tumourigenesis and uterine adenomyosis in mice are regulated by both genetic and environmental factors and information about the degree of participation of each factor in these lesions is important in the use of mice for investigations. Several parameters on spontaneous mammary tumours and uterine adenomyosis in four strains of mice with different potentials for these lesions were compared in those before and after more than 40 generations or more than 10 years (1987). During these periods, the mice were exposed to several different intangible or unavoidable environmental factors, although they are quite stable genetically by maintenance with full-sib mating. Nevertheless, small differences were observed between the present and 1987 regarding strain-related characteristics, such as the onset age, the cumulative incidence and the growth of mammary tumours and uterine adenomyosis. It is suggested that genetics is more influential than environmental factors regarding the maintenance of strain-related characteristics of mammary and uterine lesions.

II s'agit de la premiere observation de l'infestation du bovin domestique (Bos taurus) par Sarcocyslis cruzi aux Philippines. Des sarcocystes fusiformes (183-578 μm de long sur 20-98 μm de large) avec un septum distinct ont ete observes au niveau des muscles stries squelettiques et cardiaque. La paroi du sarcocyste ou membrane vacuolaire parasitophore, epaisse de 1,37-2,75 μm presente en un amas de protrusions villositaires (PV) de 80-400 nm de diametre. Les segments moyen et distal des PV sont flechis d'environ 90° par rapport a la surface de la paroi, Le corps de la villosite manque de microtubule et, en certains endroits, les extremites distales des PV forment des huppes coniques. La paroi des cystes presente des ondulations qui ressemblent a des bulles de 70-100 nm, et la membrane basale est epaisse de 0,25-0,50 μm. L'ultrastructure de la paroi de S. cruzi est de meme type que celle de la paroi du sarcocyste de Type 7, et presente d'etroites similitudes avec les souches de Sarcocystis levinei observees chez le bubale au Philippines et au Vietnam.

Biosynthesis of gelatinase, a virulence factor of Enterococcus faecalis, was found to be regulated in a cell density-dependent fashion in which its production is active in late log to early stationary phase. Addition of early stationary phase culture filtrate to medium shifted the onset of gelatinase production to that of mid-log phase, suggesting that E. faecalis secretes a gelatinase biosynthesis-activating pheromone (GBAP). GBAP was isolated from culture supernatant of E. faecalis OG1S-P. Structural analysis suggested GBAP to be an 11-residue cyclic peptide containing a lactone structure, in which the alpha-carboxyl group of the C-terminal amino acid is linked to a hydroxyl group of the serine of the third residue. A synthetic peptide possessing the deduced structure showed GBAP activity at nanomolar concentrations as did natural GBAP. Database searches revealed that GBAP corresponds to a C-terminal part of a 242-residue FsrB protein. Northern analysis showed that GBAP slowly induces the transcription of two operons, fsrB-fsrC encoding FsrB and a putative histidine kinase FsrC and gelE-sprE encoding gelatinase GelE and serine protease SprE. Strains with an insertion mutation in either fsrC or a putative response regulator gene fsrA failed to respond to GBAP, suggesting that the GBAP signal is transduced by a two-component regulatory system.

Based on the importance of general metabolic activity to mammary tumourigenesis, plasma component levels were examined at 6 and 10 months of age in female virgin mice of four strains, which in mammary tumour potential, rank in the descending order of SHN, GR/A, SLN and C3H/He. The plasma aspartate aminotransferase level elevated from 6 to 10 months of age in the SHN and GR/A, but not in the SLN and C3H/He strains. The total bilirubin level was higher in the former two strains than the latter two at both 6 and 10 months. The blood urea nitrogen level was highest in SHN. C3H/He had the lowest plasma levels of these components as well as amylase at both ages. The results indicate the signifcance to the mammary tumourigenic potential of plasma levels of certain components related to general metabolic activity.

Penaeoid shrimp oocytes nearing the completion of oogenesis are enveloped in an acellular vitelline envelope and possess extracellular cortical rods (CRs) that extended into the cortical cytoplasm. These cortical specializations are precursors of the jelly layer (JL) of the egg. In searching for highly expressed mRNAs during oogenesis in the marine shrimp (Penaeus semisulcatus), two related cDNAs have been isolated that encode a mature protein of 250 amino acid residues. The deduced amino acid sequences revealed the presence of repeated cysteine-rich domains that are related to the chitin-binding domains of insect intestinal peritrophins. Similar cysteine-rich domains were reported in insect intestinal mucin, crustacean tachycitin, and invertebrate chitinases. The shrimp ovarian peritrophin (SOP) is glycosylated and can bind chitin when extracted from CRs. Its apparent molecular mass in SDS-PAGE is 29-35 kDa and 33-36 kDa, under nonreducing or reducing conditions, respectively. SOP is a major protein of CRs and the JL, and was immunodetected in ovaries; purified CRs; fertilized eggs that were surrounded by a JL matrix; and in the cloudy, whitish flocculent material appearing in sea water immediately after spawning. Immunolocalization in tissue sections determined that SOP was present in oocyte cytoplasm and in extraoocytic CRs. Shrimp expressed SOP mRNA in ovaries at all oocyte developmental stages, whereas expression in the hepatopancreas was restricted to vitellogenic stages. SOP mRNA was abundant in the shrimp ovary and was detected before the presence of the corresponding protein. This is the first demonstration that a protein with similar features to insect intestinal peritrophins is a component of CRs and is therefore a main precursor of the JL of spawned shrimp eggs.

Based on findings that free access in drinking water of the extract of coffee cherry (CC), the residue left after the removal of coffee beans, and whole-body hyperthermia (WBH) induced by far-infrared ray (FIR) can markedly inhibit the growth of spontaneous mammary tumours of SHN mice, the effects of the combined treatment with these agents were examined in this study. The significant inhibition of tumour growth by single treatment with either CC or WBH was not enhanced by their combination. Meanwhile, the body weight loss during WBH was significantly decreased by CC. Normal and preneoplastic growth of mammary glands and plasma component levels were affected little by either treatment. The findings confirmed the "normalization effects" of CC usually obtained with natural products and stress the need for prudence in the choice of any agent, natural or synthetic, to be applied simultaneously to increase the efficacy of WBH.

The effects of chronic exposure to far-infrared ray (FIR) on reproduction, growth, behaviour, survival time and some related parameters were examined in SHN mice. The reproductive parameters differed slightly between the females on the normal racks and those on the FIR racks, which emitted FIR from the ceiling. The age and body weight on the day of vaginal opening was lower in the experimental mice born and maintained on the FIR rack than in the control on the normal rack. In both sexes, the levels of urinary components in the experimental group was significantly higher than the control at 6-7 months of age. Spontaneous motor activity of females during the light and dark phases were higher and lower, respectively, in the experimental group than the control. The survival rate was significantly higher in the experimental group than the control. These findings suggest that FIR has 'normalization effects' on the organisms.

We have found that the chronic administration of the diet containing 5% hydroxyapatite (HAP) derived from bovine or swine bone or drinking water containing 0.5% extract of coffee cherry (CC), the residue left after the removal of coffee beans, induced a marked inhibition of spontaneous mammary tumourigenesis in SHN mice, while the effects decreased with age. In the present study, the combined effects of HAP and CC on mammary tumourigenesis and related parameters were examined. The inhibitory effects of HAP or CC alone on the development and/or the growth of mammary tumours were reduced by HAP + CC. Decreased food and water intake and retarded body growth caused by CC were ameliorated by HAP. Enhancement by HAP or CC of the excretion of the urine components was mostly nullified by HAP + CC. Parameters such as normal mammary gland growth and uterine adenomyosis on which neither HAP nor CC had an effect also did not respond to HAP + CC. These findings suggest that the target is important when administering natural products in combination if the agents are to manifest their effects, additive, synergistic, antagonistic or otherwise.

We examined the induction of HPRT mutations in CHO cells exposed to low fluences of (238)Pu alpha particles from a specially constructed irradiator. The dose-response relationship was linear over the dose range of 5 cGy-1.2 Gy. However, unexpected sensitivity, leading to a significantly higher frequency of mutations than would be predicted by a back extrapolation from the data for higher doses, was observed in the dose range below 5 cGy, where the mean number of alpha-particle traversals per nucleus was significantly less than one (0.05-0.3). The frequency of mutations induced by a single alpha particle traversing the nucleus of a cell was increased nearly fivefold at the lowest fluence studied. The data are consistent with the conclusion that the enhanced efficiency of each nuclear traversal at low particle fluences is the result of mutations arising in nonirradiated, bystander cells.

The xeroderma pigmentosum (XP) variant (XPV) is a form of XP that has normal excision repair but shows defective DNA replication after UV irradiation. In developing various transformed fibroblast cell lines from these patients, we have found that there are significant phenotypic changes in transformed cells that seem to correlate with inactivation of p53. After transformation with SV40, XPV cell lines are only slightly UV sensitive, like their primary counterparts, but their sensitization with caffeine and the induction of sister chromatid exchanges (SCEs) by UV irradiation are greatly enhanced. After transformation by HPV16 E7, which targets the retinoblastoma cell cycle regulatory gene, there is no change in the UV sensitivity of XPV cells; but, when transformed by HPV16 E6 or E6 and E7 combined, there is a large increase in UV sensitivity and in the induction of SCEs. These changes are not associated with any detectable changes in the reactivation of an externally irradiated luciferase expression vector, the excision of cyclobutane pyrimidine dimers from bulk DNA, or unscheduled DNA synthesis and, therefore, do not involve excision repair. We suggest that if SCEs represent homologous recombination between sister chromatids, then in the absence of p53 function, the DNA chain arrest typical of UV-damaged XPV cells initiates strand exchange during recovery. In untransformed cells with normal p53, the preferred mode of recovery would then be replication bypass. The symptoms of elevated solar carcinogenesis in XPV patients may, therefore, be associated with increased genomic instability in cells of the skin in which p53 is inactivated by UV-induced mutations.

The spontaneous behaviour at late pregnancy was measured as motor activity by Supermex in SHN mice, which have a rather high still-birth rate. The activities during both light and dark phases as well as during the total period were significantly higher in mice with still-birth than those with normal delivery. Meanwhile, in normal delivery group, there was little correlation between the spontaneous activity and the reproductive parameters, except for litter size or total pup weight. These results strongly suggest that calmness, especially at late pregnancy is prerequisite for normal delivery and that reproduction itself after delivery was not markedly affected by the behaviour of mother at late pregnancy.

The relationship between the onset age of mammary tumours and some reproductive parameters was examined in 4 strains of mice with mammary tumour potential in the order of SHNSLNGR/AC3H/He. The onset age of mammary tumours of SHN, in which no difference was observed between the parous and virgin animals in the mammary tumour potential, was effected little by reproduction. However, in this strain, the age at first parturition was earlier in the individuals with early onset age of mammary tumours than in those with late onset age. In GR/A, the onset age of mammary tumours had a significantly negative correlation with rearing rate and the rearing rate was higher in the individuals with early onset age than those with late onset age. While the onset ages of mammary tumours had significant correlations with some reproductive parameters in both SLN and C3H/He, the degree was much higher in C3H/He than in SLN, well paralleling mammary tumour potential. These findings have demonstrated that the higher mammary tumour potential in parous mice than in virgins is ascribed principally to the stimulation of mammary gland growth and mammotrophic hormone secretion, which, in turn, results in an increase in the risk of malignant transformation of the cells and their progression, and that the influence of reproduction is greater in the lower mammary tumour strains.

We present evidence that inactivation of the Ku70 gene leads to a propensity for malignant transformation both in vitro and in vivo. In vitro, Ku70-/- mouse fibroblasts displayed an increased rate of sister chromatid exchange and a high frequency of spontaneous neoplastic transformation. In vivo, Ku70-/- mice, known to be defective in B but not T lymphocyte maturation, developed thymic and disseminated T cell lymphomas at a mean age of 6 months with CD4+CD8+ tumor cells. These findings directly demonstrate that Ku70 deficiency facilitates neoplastic growth and suggest a novel role of the Ku70 locus in tumor suppression.

It is well known that normal human diploid fibroblasts undergo a significant, p53-dependent arrest in the G1 phase of the cell cycle after exposure to ionizing radiation. The presence and magnitude of a G1 arrest in human tumor cell lines, however, has been controversial, particularly in cells derived from solid tumors and irradiated during exponential growth. To examine this question more precisely, we synchronized cells by mitotic selection and irradiated them in very early G1 prior to any of the described G1 checkpoints. Progression of cells from G1 into the S phase was monitored by autoradiographic measurement of cumulative labeling indices and by flow cytometric analysis. Three different human tumor cell lines confirmed as expressing normal p53 function were examined, i.e., lines derived from an adenocarcinoma of the colon (RKO), a breast cancer (MCF-7), and a squamous cell carcinoma (SCC61). Following irradiation with 4-8 Gy, there was a transient delay in progression from G1 into S phase, lasting approximately 2 h, and in two of the three cell lines (RKO and MCF-7), a small fraction of cells (5-8%) never entered the first S phase. Although there was no evidence for a prolonged G1 arrest, the expected G2 delay was observed in all three cell lines. When irradiated RKO cells were resynchronized at the next mitosis, approximately 30% of the cells did not enter the second S phase. This latter finding is consistent with earlier reports on the kinetics of radiation-induced reproductive failure in mammalian cells. These results indicate that cells derived from human solid tumors that express normal p53 may respond to irradiation quite differently than do normal cells in terms of G1 checkpoint control.

The characteristics of GR/A mice are rather poor pup growth and vigorous activity associated with increased excretion of taurine during pregnancy and lactation. The relationship between taurine and these characteristics were studied. The group of GR/A mice given a 1% taurine solution in their drinking water on the first day of pregnancy (day when the vaginal plug was found) (group I) or on the day of parturition (group II) differed little from the control group given tap water in all reproductive parameters, including pup growth. The spontaneous motor activities of both the female and male 4-month-old offspring of group I were markedly lower than those of the offspring of the control and group II, and than that of group III, which was given taurine after of weaning. These findings strongly suggest that taurine, possibly by acting on the developing brain at the fetal stage, has a long-term effect on the behaviour of this strain of mice, while it has little effect on their reproduction.

The behaviour of four strains of virgin and lactating mice with different physiological characteristics (SHN, SLN, GR/A and C3H/He) were compared. In virgin, the motor activity, determined by Supermex, was high in all strains shortly after the start of the test, especially in GR/A. In this strain, the high activity continued longer and was also observed before the dark phase. In both the entire 48 hours and the last 24 hours of measurement, GR/A showed higher activity than the other strains during the light phase, but not during the dark phase. These data suggest that GR/A is more sensitive and thus has lower adaptability to a new environment than the other strains and that the biological clock of this strain differs from the others. The frequency and the period in or out of the nest as estimated by a video monitor were smaller and longer, respectively, in SLN than in the other strains. However, no relationship was found between the pattern of behaviour at lactation and the pup growth as an index of lactational performance.

Changes in urinary component levels before, during and after reproduction were examined with 1H-nuclear magnetic resonance (NMR) in four strains of female mice with different mammary tumour potential and related characteristics (SHN, SLN, GR/A and C3H/He). Regardless of the variations in these changes among the strains, the urinary component levels reflected physiological changes during reproduction and some strain-specific characteristics. The urinary excretion of citrate, 2-oxoglutarate and lactate increased from the virginal stage to pregnancy and declined during lactation in all strains, indicating a marked change in sugar metabolism during reproduction. SHN and SLN, which are from the same basal stock, showed a similar pattern and the level, of several components were lower than those of GR/A and C3H/He. The levels of some lower components were compensated for by higher urine excretion. The levels of taurine and betaine, both essential for fetal and pup growth, increased at lactation in only GR/A, reflecting the poorer pup growth observed in this strain. Finally, the 1H-NMR method was useful to estimate not only the metabolic but also the physiological changes of the animals without invasion, pain or distress and would thus contribute to animal welfare in the animal experiments.

Plasma levels of human growth hormone (hGH) were determined in female and male transgenic mice with human growth hormone fusion gene driven by the promoter of mouse whey acidic protein (mWAP/hGH) at 3, 6 and 9 months of age and at mammary tumour appearance. In female transgenic mice developing mammary tumours, the plasma hGH level decreased markedly upon tumour appearance, which was associated with little change in body weight. In contrast, the hGH level changed little in transgenic male mice with tumours. In female and male transgenic mice without mammary tumours, the pattern of the change of hGH levels was variable; some showed high levels at all three time points (3, 6, and 9 months) and others had none or high levels at one or two time points.

Three widely studied cell lines were used to examine the nature of the G1 arrest induced in human tumor cells by ionizing radiation and its relation to p53 status. Cell lines MCF-7 and RKO express wild-type p53, whereas HT29 expresses mutant p53. Exponentially growing cells were irradiated with 6 Gy, and the progression of G1 cells into S phase was monitored at regular intervals by flow microfluorimetric and continuous labeling autoradiographic techniques. In some experiments, cells were incubated with Colcemid prior to irradiation in order to block them in mitosis and to prevent the accumulation of cells in the second post-irradiation G1 phase. No evidence of a significant arrest at the first post-irradiation G1-S checkpoint was observed in any of the three cell lines. These results suggest that p53 function alone does not control the progression of irradiated human tumor cells from G1 into S during the first post-irradiation cell cycle. In particular, we found no evidence that radiation induced a prolonged G1 arrest in tumor cells expressing wild-type p53 as has been reported by some investigators.

Toxoplasma gondii is an obligate intracellular protozoan parasite and cellular immunity plays a crucial role in protection against infection with this pathogen. When mice are immunized with Toxoplasma homogenate, they readily acquire resistance against infection with a lethal dose of a low virulence Beverley strain of T. gondii. We have reported previously that expression of 65,000 MW heat-shock protein (hsp 65) in host macrophages closely correlates with protective potentials of hosts, while this protein is not expressed in Toxoplasma themselves. In this study, we examined the mechanism of expression of hsp 65 in mice immunized with Toxoplasma homogenate. Heat-shock protein was detected in peritoneal macrophages of BALB/c mice immunized 7 days previously by electroblot assay with a specific monoclonal antibody (mAb) for microbial hsp 65. Furthermore, an immunogold ultracytochemistry assay demonstrated that this protein was expressed on the cell surface of peritoneal macrophages in immune mice. This expression was not induced in those of immune athymic nude mice and SCID mice. Treatment of BALB/c mice with anti-Thy-1.2 mAb 1 day before immunization led to an almost complete loss of the expression of hsp 65. To determine the subsets of T cells responsible for induction of this protein, mice were depleted of gamma delta T cells, alpha beta T cells, CD4+ T cells or CD8+ T cells by treating with corresponding antibodies before immunization. From these experiments, gamma delta T cells were shown to be essential for the expression of hsp 65, although CD4+ alpha beta T cells also contributed to some extent. Thus, gamma delta T cells appear to play an important role in protective immunity against infection with T. gondii through mediating the expression of hsp 65 in host macrophages.

Biochemical and Dynamic change of mammary glands in different reproductive states were studied in comparison with histological structures in female and male transgenic mice bearing human transforming growth factor alpha (TGF alpha) cDNA under the control of the mouse mammary tumour virus enhancer/promoter. Female and male F1 mice between SHN female and transgenic male mice were divided into TGF alpha (+) and TGF alpha (-) groups according to the presence of TGF alpha gene at approximately 50 days of age. While there was little difference in mammary gland contents of DNA and RNA in females at 2 months of age, both nucleic acid contents were elevated markedly in TGF alpha (+) female mice with large variations at 4 months. These extremely high DNA and RNA contents in the TGF alpha (+) group declined to the level of the TGF alpha (-) group in the middle of pregnancy and at the end of pregnancy, respectively. Thymidine kinase (TK) activity in the mammary glands as an index of DNA synthesis was significantly higher in TGF alpha (+) mice than in TGF alpha (-) mice at both 2 and 4 months of age and the high TK in TGF alpha (+) mice also declined to the level of TGF alpha (-) mice with pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)