Diagnostic Value of Model-Based Iterative Reconstruction Combined with a Metal Artifact Reduction Algorithm during CT of the Oral Cavity

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.

Effect of manual lymph drainage for up to 10 days after total knee arthroplasty: Arandomized controlled trial

OBJECTIVE

To assess the effect of manual lymph drainage (MLD) on pain in Japanese patients up to 10 days after a total knee arthroplasty (TKA).

METHODS

This study was a randomized controlled trial performed at a University Medical Center. Patients who underwent unilateral TKA and received once daily MLD for 20 minutes prior to standard physical therapy up to 10 days after TKA were investigated. Pain at rest, knee extension muscle contraction, and maximum load were assessed using the visual analog scale (mm) before surgery, after drain removal, and after the fifth MLD. As secondary outcomes, the circumference, range of motion, muscle strength, walking speed, and walking rate were evaluated.

RESULT

Forty-one patients aged 45-85 participated in this study, 21 of whom were assigned to the intervention (MLD group) and 20 who were not (control group). Ten days after TKA, no significant difference was evident between the MLD and control groups for resting pain [4.5 mm (1.6-10.8) vs 7.0 mm (1.8-25.5), respectively, p=0.17], pain during knee extension muscle contraction [12.3 mm (4.5-24.8) vs 20.8 mm (6.4-31.8), p=0.41], and pain at maximum load [13.0 mm (8.3-39.8) vs 16.0 mm (4.6-32.5), p=0.73]. There were no significant differences between groups in terms of secondary outcomes.

CONCLUSION

This study shows that MLD up to 10 days after TKA does not affect pain.

Signal detection of oral drug-induced dementia in chronic kidney disease patients using association rule mining and Bayesian confidence propagation neural network

Among the mechanisms responsible for cognitive dysfunction in chronic kidney disease (CKD) are albuminuria and oxidative stress. However, there may be other causes not yet identified. In fact, the full relevance of CKD patient drug use and its relationship to dementia has hardly been barely investigated. We identified drugs affecting cognitive function in CKD patients by analyzing the spontaneous reporting system in Japan using Association rule mining (ARM) and Bayesian confidence propagation neural network (BCPNN). The signal detection criterion used were as follows: case ≥ 3, lift > 1, conviction > 1 (ARM) and IC₀₂₅ >0 (BCPNN). Drugs with more than 20 cases were valaciclovir (lift: 11.21, conviction: 1.28, IC₀₂₅: 3.12), amantadine (lift: 19.69, conviction: 1.68, IC₀₂₅: 3.05), nalfurafine (lift: 8.35, conviction: 1.19, IC₀₂₅: 2.18), pregabalin (lift: 6.05, conviction: 1.12, IC₀₂₅: 1.78), and acyclovir (lift: 5.89, conviction: 1.12, IC₀₂₅: 1.68). This study is the first report to use a large-scale medical database to identify drugs related to oral drugs-induced dementia in CKD.

Japanese civilian and US military interaction in the evacuation of casualties from Camp Fuji

Historically, if US soldiers at Camp Fuji become severely ill or suffer trauma, they are transported by the ground ambulance, as the doctor-led air ambulance in eastern Shizuoka has never been permitted to land at Camp Fuji. However, it is widely recognised that severely ill or traumatised patients require time-dependent medical management. It was therefore agreed to undertake a joint exercise between the US medical assets of Camp Fuji and the doctor helicopters in eastern Shizuoka prefecture in evacuating a simulated severely ill or traumatised US soldier. The aim of this article is to describe the background and rationale between this collaboration between the civilian Japanese air ambulance and the US medical assets in Camp Fuji.

An interpretation of the neonatal period definition obtained with echocardiographic examination by using change point regression analysis

BACKGROUND

We had reported on the left ventricular end-diastolic dimension (LVDd) in normal children from the premature/neonatal period to the adolescence period by using two-dimensional echocardiography, and formulated equations to evaluate normal LVDd values by using body height as an index. There was an inflection point at around birth that seemed relevant to the fetal and neonatal periods for the relation of LVDd and body height.

METHODS

We aimed to reveal the true inflection point and its meaning by using change point regression analysis. The study group consisted of 421 neonates and infants. The ages at examination ranged from 24 weeks' gestation to 1 year after birth. The subjects' body heights at examination were between 31 and 75 cm.

RESULTS

The analysis showed no definite inflection point in height, and a flat bottom was observed between body heights of 48 and 55 cm. The inflection range seemed to mean the duration of the neonatal period, which connects the fetal and infantile periods.

CONCLUSION

The results revealed that neonates reach the infantile period slower than usually imagined, and the end of the neonatal period may be at the age when the body height is around 55 cm- in other words, at 2 months after birth. This manuscript might be the first one to consider the definition of the neonatal period using cardiovascular methods.

Single nucleotide recognition using a probes-on-carrier DNA chip

Following the sequencing of the human genome, SNP analysis of individual patients has become essential for achieving the best drug response and ensuring optimal care. In this study, we developed a cost-effective probes-on-carrier DNA chip for the detection of SNPs. Our chips harbored three different probes against the TP53 gene, and were capable of detecting wild-type TP53 and SNPs such as rs121912651 and rs11540652. Four cell lines were used to validate the specificity of probe hybridization. Strong fluorescence intensity was observed in hybridized spots based on hybridization for perfect base pairing between complementary strands, whereas significantly lower fluorescence (p < 0.05) was observed in nonhybridized spots. These hybridization results indicated that the probes-on-carrier chip is suitable for SNP genotyping.

Inhibition of Thrombin-Neutralizing Activity of Antithrombin III by Steroid Hormones

Estrogens in high doses have been shown to inhibit, in vitro, the thrombin-neutralizing action of antithrombin III (AT III). In this study we investigate the effect of estrogens on AT III in greater detail. To increase the sensitivity of measurement of AT III activity in the absence of heparin, we have developed an assay system utilizing human platelets, AT III and thrombin. The two proteins derived from human plasma were prepared in high purity. Platelet aggregation was induced by approximately 0.02 NIH U of thrombin. AT III was added in amounts that suppressed 95% of the aggregation-inducing effect of thrombin. Estrogens blocked the thrombin-neutralizing effect of AT III in dose-dependent manner. This effect was shown to be specific for AT III. Neither aggregability of platelets nor aggregating effect of thrombin were affected by the steroid hormone. Evidence for binding of estrogen to AT III was obtained from changes in intrinsic fluorescence of AT III. Activity of AT III was also reduced in increasing order of effectiveness by cholesterol, cortisone, testosterone and progesterone. Our studies suggest a direct effect of estrogens and other steroids on AT III, altering its specific neutralization of thrombin.

Effects and feasibility of exercise therapy combined with branched-chain amino acid supplementation on muscle strengthening in frail and pre-frail elderly people requiring long-term care: a crossover trial

This study examined the effects and feasibility of a twice-weekly combined therapy of branched-chain amino acids (BCAAs) and exercise on physical function improvement in frail and pre-frail elderly people requiring long-term care. We used a crossover design in which the combination of exercise and nutritional interventions was carried out twice a week during cycles A (3 months) and B (3 months) and the exercise intervention alone was performed during the washout period. The exercise intervention entailed the following 5 training sets: 3 sets of muscle training at 30% of maximum voluntary contraction, 1 set of aerobic exercise, and 1 set of balance training. For the nutritional intervention, 6 g of BCAAs or 6 g of maltodextrin was consumed 10 min before starting the exercise. We determined upper and lower limb isometric strength, performance on the Functional Reach Test (FRT) and the Timed Up and Go test, and activity level. In the comparison between the BCAA group and the control group after crossover, the improvement rates in gross lower limb muscle strength (leg press, knee extension) and FRT performance were significantly greater (by approximately 10%) in the BCAA group. In the comparison between different orders of BCAA administration, significant effects were shown for the leg press in both groups only when BCAAs were given. The combination of BCAA intake and exercise therapy yielded significant improvements in gross lower limb muscle strength and dynamic balance ability.

Interpretation of left ventricular dimensions of neonates obtained from echocardiographic examinations during the early neonatal period

BACKGROUND

In neonates without physiological pulmonary hypertension, left ventricular end-diastolic dimensions (LVDd) are determined with two-dimensional echocardiography and formulated equations. However, there has not been discussed the meanings of dimensions in early neonatal periods, although the short-axis view of the left ventricle is not round at this age. The objective of this study was to assess LVDd in neonates during early neonatal periods.

METHODS

The study group consisted of 460 full-term neonates (230 boys; 230 girls) without congenital heart disease. The iE33 apparatus was employed to examine and measure the LVDds and the longest and shortest dimensions in the short-axis view.

RESULTS

A significant difference was observed between the real LVDds and the estimated normal dimensions that were calculated from the formula; LVDd(mm) = 0.352 × Ht(cm)+1.86), (P = 0.020). The mean LVDds were estimated to be 97% of the normal LVDds. The real LVDds were influenced by the angle formed by the real LVDds and the longest dimension.

CONCLUSIONS

The real LVDds were shorter than normal LVDds. These findings establish normal values for LVDds in the early neonatal period.

[Effects of exercise intervention on exercise behavior in community-dwelling elderly subjects: a randomized controlled trial]

AIM

The objective of the present study was to evaluate the long-term effectiveness of an exercise program in modifying the exercise behavior of the community-dwelling elderly subjects.

METHODS

This study was a single-blinded randomized controlled trial. The subjects included 52 males and 65 females 65 years of age or over who were randomly assigned to an exercise-intervention group or a health-education group. The stages of change in exercise behavior were evaluated before and one-year after the intervention period. The subjects' physical function (muscle strength, balance, walking speed) and self-efficacy in each domain of the physical function were measured during the intervention period.

RESULTS

There were no significant differences in the stages of change before the intervention between the two groups. Significant differences in the stages of change were observed in "relapse" of stages at two points in time between the two groups (p<.01). A logistic regression analysis showed that "progression" of stages was associated with improvements in the timed up and go test (AOR 2.7; 95% CI 1.3-5.8) and sit and reach (AOR 1.14; 95%CI 1.0-1.3), while "relapse" of stages was associated with the group allocation (AOR 4.6; 95%CI 1.1-18.8), self-efficacy in "Walking" (AOR 1.54; 95%CI 1.0-2.3) and "Stair climbing" (AOR 0.68; 95%CI 0.5-0.9) with respect to physical activity during the intervention period.

CONCLUSIONS

The results suggest that exercise intervention in community-dwelling elderly subjects is effective in preventing "relapse" of exercise behavior over long periods.

Amino acid sequence of a prothoracicotropic hormone of the silkworm Bombyx mori

We have determined the complete amino acid sequence of 4K-PTTH-II, one of three forms of the M(r) 4400 prothoracicotropic hormone of the silkworm Bombyx mori, active to brainless pupae of Samia cynthia ricini. Like vertebrate insulin, it consists of two nonidentical peptide chains (A and B chains). The A chain consists of 20 amino acid residues. The B chain is a mixture of four microheterogeneous peptides, two of which consist of 28 residues, and the other two, of 26 residues. 4K-PTTH-II has considerable sequence homology (40%) with human insulin, and it resembles porcine relaxin both in the carboxyl-terminal cysteine residue of the A chain and in the amino-terminal pyroglutamic acid residue of the B chain. The identical distribution of the six cysteine residues also indicates that 4K-PTTH-II belongs to the insulin family.

Cystatin C as an index of cerebral small vessel disease: results of a cross-sectional study in community-based Japanese elderly

BACKGROUND AND PURPOSE

Recent studies have shown that kidney dysfunction is associated with cerebral small vessel disease (SVD). Although creatinine-based estimating equations have been used as the standard measure for the evaluation of kidney function, the accuracy of these is limited in the elderly because of muscle mass decrease with aging. Cystatin C is a more useful measurement than creatinine-based estimating equations for evaluating kidney function, however, the relationship amongst cystatin C, cognitive dysfunction, and cerebral SVD has not been fully examined in community-based elderly.

METHODS

We performed a cross-sectional study using MRI to determine the relationship amongst cystatin C, cognitive function, and cerebral SVD in a total of 604 community-based Japanese elderly.

RESULTS

In this study, subjects with higher cystatin C levels tended to have more lacunas and higher grades of white matter lesions. Although a decline of the Mini-Mental State Examination (MMSE) scores was associated with SVD-related lesions, the relationship between the tertiles of cystatin C and mean MMSE scores was not statistically significant. In the logistic regression analysis, the association between cystatin C and SVD-related lesions was statistically significant, even after adjustment for conventional risk factors and high-sensitivity C-reactive protein. Furthermore, subjects with higher cystatin C levels accompanied with albuminuria had a greater risk for the presence of subclinical cerebral SVD than those with lower cystatin C levels without albuminuria.

CONCLUSIONS

The present study suggests that there is a close relationship between cystatin C and subclinical cerebral SVD, independently of conventional risk factors, in community-based elderly.

The usefulness of continuous administration of hypoxic cytotoxin combined with mild temperature hyperthermia, with reference to effects on quiescent tumour cell populations

To evaluate the usefulness of continuous administration of hypoxic cytotoxins in terms of targeting acute hypoxia in solid tumours and the significance of combination with mild temperature hyperthermia (MTH) (40 degrees C, 60 min), the cytotoxic effects of singly or continuously administered tirapazamine (TPZ) and TX-402 were examined in combination with or without MTH in vivo. Further, the effects were also analysed on total (=proliferating (P)+quiescent (Q)) and Q cell populations in solid tumours with the method for selectively detecting the Q cell response. C3H/He mice bearing SCC VII tumours received a continuous administration of 5-bromo-2'-deoxyuridine (BrdU) for 5 days to label all P cells. The tumour-bearing mice then received a single intra-peritoneal injection or 24 h continuous subcutaneous infusion of hypoxic cytotoxin, TPZ or TX-402, with or without MTH. On the other hand, to detect the changes in the hypoxic fraction (HF) in the tumours by MTH, another group of mice with or without MTH received a series of test doses of gamma-rays while alive or after tumour clamping. After each treatment, the tumour cells were isolated and incubated with a cytokinesis blocker (=cytochalasin-B) and the micronucleus (MN) frequency in cells without BrdU labelling (=Q cells) was determined using immunofluorescence staining for BrdU. The MN frequency in total tumour cells was determined from the tumours that were not pre-treated with BrdU. The sensitivity to TX-402 was slightly higher than that to TPZ in both total and Q tumour cells. Continuous administration elevated the sensitivity of both total and Q cells, especially total cells. MTH raised the sensitivity of Q cells more remarkably than that of total cells in both single and continuous administrations. It was thought to be probably because of the higher dose distribution of hypoxic cytotoxin in intermediately hypoxic areas derived mainly from chronic hypoxia through MTH. From the viewpoint of tumour control as a whole including both total and Q tumour cells, the continuous administration of hypoxic cytotoxin combined with MTH may be useful for sensitizing tumour cells in vivo.

Differing effects of breast cancer 1, early onset (BRCA1) and ataxia‐telangiectasia mutated (ATM) mutations on cellular responses to ionizing radiation

PURPOSE

The ataxia-telangiectasia mutated (ATM) gene encodes a protein kinase, the activation of which is an early event in the cellular response to ionizing radiation. One of the many substrates of ATM is BRCA1 (breast cancer 1, early onset gene), which has been associated with susceptibility to breast and ovarian cancer, and has been implicated in DNA repair processes. Various cellular responses to radiation were analysed in cells with mutations in ATM or BRCA1 in an attempt to clarify which effects of ATM can be mediated through BRCA1.

MATERIALS AND METHODS

The response to radiation of cells with mutations in ATM or BRCA1 was examined, as were BRCA1-mutant tumour cells transfected with an exogenous wild-type BRCA1 allele. Assays included cell-survival curves, studies of potentially lethal damage repair, measurement of chromosomal aberrations and of G1 arrest, and Western blot analysis of lysates of irradiated cells to determine the phosphorylation of the product of the human Mdm2 gene (HDM2).

RESULTS

Both ATM and BRCA1 mutations were associated with sensitivity to ionizing radiation, deficient repair of potentially lethal damage and markedly increased chromosomal aberrations. A BRCA1-mutated tumour cell line HCC1937, like ATM mutant cells, did not exhibit a normal G1 arrest but, unlike ATM mutant cells, did exhibit phosphorylation of HDM2. Expression of wild-type BRCA1 in HCC1937 cells partially restored radioresistance, restored repair of potentially lethal damage and markedly reduced radiation-induced chromosomal aberrations. G1 arrest, however, was not restored by expression of BRCA1.

CONCLUSIONS

The results are consistent with a model in which ATM phosphorylation of BRCA1 regulates DNA repair functions, particularly those involved in potentially lethal damage repair and chromosomal integrity, but not other aspects of the cellular response to radiation such as G1 cell cycle arrest. To the authors' knowledge, this is the first demonstration of the ability of exogenously expressed BRCA1 to restore the ability to perform potentially lethal damage repair and maintain chromosomal integrity in irradiated cells.

'Protected DNA Probes' capable of strong hybridization without removal of base protecting groups

We propose a new strategy called the ‘Protected DNA Probes (PDP) method’ in which appropriately protected bases selectively bind to the complementary bases without the removal of their base protecting groups. Previously, we reported that 4-N-acetylcytosine oligonucleotides (ac⁴C) exhibited a higher hybridization affinity for ssDNA than the unmodified oligonucleotides. For the PDP strategy, we created a modified adenine base and synthesized an N-acylated deoxyadenosine mimic having 6-N-acetyl-8-aza-7-deazaadenine (ac⁶az⁸c⁷A). It was found that PDP containing ac⁴C and ac⁶az⁸c⁷A exhibited higher affinity for the complementary ssDNA than the corresponding unmodified DNA probes and showed similar base recognition ability. Moreover, it should be noted that this PDP strategy could guarantee highly efficient synthesis of DNA probes on controlled pore glass (CPG) with high purity and thereby could eliminate the time-consuming procedures for isolating DNA probes. This strategy could also avoid undesired base-mediated elimination of DNA probes from CPG under basic conditions such as concentrated ammonia solution prescribed for removal of base protecting groups in the previous standard approach. Here, several successful applications of this strategy to single nucleotide polymorphism detection are also described in detail using PDPs immobilized on glass plates and those prepared on CPG plates, suggesting its potential usefulness.

An effective method for the in situ synthesis of DNA-CPG conjugates using chemical ligation technology as tools for SNP analysis

In this paper, we report a new method for the SNP analysis by using a chemical ligation (CL) technique on CPG plates with high coupling efficiency. This method showed markedly high match/mismatch discrimination ability. Particularly, replacement of thymidine with 2-thiothymidine in DNA probes used in the CL technology resulted in significant improvement of the base discrimination ability of the thymine base in this system.

Toxoplasma gondii infection induces apoptosis in noninfected macrophages: role of nitric oxide and other soluble factors

Apoptosis has been found to help in the defence against pathogens. Infection with the obligate intracellular parasite Toxoplasma gondii is known to trigger host-cell apoptosis. When using a T. gondii-infected macrophage cell line, J774A.1, treatment with IFN-gamma significantly enhanced apoptosis in noninfected bystander cells while parasitized cells became relatively resistant. Infection and IFN-gamma treatment activated the expression of inducible nitric oxide synthase (iNOS), and the production of nitric oxide (NO) and treatment of cells with an iNOS inhibitor, N(G)-monomethlyl-L-arginine acetate (L-NMMA) reduced the apoptosis frequency. However, the reversal was only partial suggesting that not only NO, but also other, as of yet, unknown factors are induced. Finally, we studied the effect in vivo by infecting mice with either a virulent or an avirulent strain. Challenge with the virulent strain lead to a higher parasite burden, induced host-cell apoptosis in peritoneal cells, and produced higher levels of IFN-gamma and NO. Moreover, treatment of mice with a NO synthase inhibitor, aminoguanidine, partially inhibited the host-cell apoptosis induced by the parasite infection. Altogether, our findings indicate that apoptosis in bystander host cells is due to the secretion of NO and other soluble factors released by parasite-infected cells.

A polymorphism of the aldehyde dehydrogenase 2 gene is a risk factor for multiple lacunar infarcts in Japanese men: the Takahata Study

The objective of the present study was to examine the association between a polymorphism of the aldehyde dehydrogenase 2 (ALDH2) gene and lacunar infarcts of the brain. We conducted a population-based, cross-sectional study on residents from two age groups (61- and 72-year olds). A total of 376 subjects participated in the study, which included brain magnetic resonance image and genetic analysis of the ALDH2 gene. Of the 61- and 72-year-old subjects, 46.4% and 64.3%, respectively, had one or more lacunar infarcts. The average number of infarcts also increased from 2.0 to 2.8 in men and from 2.3 to 3.5 in women. No significant association between the ALDH2 genotype and the presence of lacunar infarction (> or =1) was found. However, in subjects with lacunar infarction, the genotype of ALDH2 *1/*1 was associated with a larger number of the lesion ['single' versus 'multiple' odds ratio (OR) 3.73, 95%CI: 1.43-9.74] in men. The OR was comparable even after adjusting for alcohol consumption, tobacco habits, age, hypertension, hypercholesterolemia, and diabetes mellitus (DM) (OR 3.88; 95% CI: 1.10-13.66). In women, there was no significant association between the ALDH2 genotypes and lacunar infarcts. The present study revealed that the ALDH2 *1/*1 genotype was significantly associated with the prevalence of multiple lacunar infarcts in Japanese men.

Reactivity of Synthetic SAG1 (p30) Peptide Sequences with RH, S273 and Beverley Strain-Induced Anti-Toxoplasma gondii Antibodies

OBJECTIVES

We compared the reactivity of IgG1 and IgG2a antibodies in mouse sera after infection with virulent RH and low-virulent S273 and Beverley strains of Toxoplasma gondii against RH SAG1 recombinant p30 (rp30) and synthetic SAG1 peptides.

METHODS

Infected mouse serum samples were collected 9 days after infection, and the level of total IgG, IgG1 and IgG2a against the RH SAG1 rp30 protein and twenty peptides of the RH SAG1 protein were assessed. The glycosylphosphatidylinositol (GPI) modification site, the hydrophilic-hydrophobic structure, the transmembrane region and the secondary structure of the SAG1 sequence of virulent and low-virulent strains were analyzed using software.

RESULTS

The virulent strain-infected mice produced a higher level of IgG1 but a lower IgG2a against the rp30 antigen, while the low-virulent strain-infected mice produced a higher level of IgG2a than the virulent strain. The difference in the secondary structure of SAG1 protein between the virulent and low-virulent strain was largely confined to amino acid positions 291-336, showing mutations and GPI anchor site.

CONCLUSION

The difference in the reactivity of IgG against the rp30 antigen and synthetic peptides between virulent and low-virulent strains points to the importance of the primary and secondary structure assumed by antigens in the activation of Th cells and, subsequently, in the induction of IgG and its subclasses.

Hypoxia accelerates cancer invasion of hepatoma cells by upregulating MMP expression in an HIF-1alpha-independent manner

Tumor hypoxia has been reported to induce tumor progression in several carcinomas. Current studies have shown that hypoxia inducible factor-1alpha (HIF-1alpha) is stabilized under hypoxic conditions and transactivates various genes related to cancer aggressiveness. In the present study, we examined whether hypoxia affects cancer invasion in hepatocellular carcinoma. We aimed to solve the molecular mechanism of tumor invasion under the hypoxic condition. We showed that tumor hypoxia accelerated cancer invasion in two hepatoma cell lines. Using Western blot and RT-PCR analyses we demonstrated striking evidence that the expression of HIF-1alpha, ETS-1, MMP-7 and MT1-MMP was strongly upregulated by hypoxic stimulation. To examine whether these invasion-related genes are regulated by HIF-1alpha, we treated hepatoma cells with TX-402, which was reported to repress HIF-1alpha expression. HIF-1alpha expression was strongly repressed by the TX-402 treatment. In contrast, the expression of ETS-1, MMP-7 and MT1-MMP mRNA was not affected by TX-402 treatment. We further established stable transfectants in which HIF-1alpha dominant negative vector was introduced into Hep3B cells (pHIF-1alphaDN). In the pHIF-1alphaDN cells, the expression of ETS-1, MMP-7 and MT1-MMP was not repressed. Moreover, the invasion activity of pHIF-1alphaDN was not altered, compared with that of the mock. In hepatoma cells, we provided evidence that hypoxic stress accelerates cancer invasion by upregulating ETS-1 and the MMP family by an HIF-1alpha-independent pathway.

The Effects of Short-Term Exercise Intervention on Falls Self-Efficacy and the Relationship between Changes in Physical Function and Falls Self-Efficacy in Japanese Older People

OBJECTIVE

To evaluate the effects of short-term exercise intervention on falls self-efficacy and to evaluate the relationships between baseline falls self-efficacy and changes in physical function in older people.

DESIGN

Single-blinded randomized controlled trial. The participants were 171 subjects aged 65 and older. They were randomly assigned into an exercise intervention group or a health education group. The subjects in the exercise intervention group performed an exercise program for 3 mos. Falls self-efficacy was measured using the falls efficacy scale (FES). The measurements of physical function included static and dynamic balance, walking velocity, flexibility, and strength.

RESULTS

There was no significant improvement of FES in either group. But there were significant negative correlations between baseline FES score and the change in maximum walking velocity (r = -0.29, P < 0.018) and knee extensor strength (r = -0.25, P < 0.040. Linear regression analysis showed that the change in static balance was related to baseline FES.

CONCLUSIONS

The results suggest that a short-term exercise intervention had no effect, possibly because of the high baseline FES scores of the participants, on the confidence of community-dwelling older persons. However, the negative association between FES score and increases in some measures of function suggest that short-term exercise may be beneficial to a subset of older persons with lower FES scores.

[Development of a rating scale for self-efficacy of physical activity in frail elderly people]

AIM

The purpose of the present study was to 1) development the scale of the self-efficacy of physical activity in frail elderly people (SEPAF), 2) investigate the relationship of physical functions and instrumental activity of daily living (IADL).

METHODS

The study included 187 community-dwelling elderly people. Subject's SEPAF (walking, stair-climbing, lifting a weight), physical functions (usual gait speed, maximum gait speed, knee extension muscle strength, hand grip) and IADL according to the Tokyo Metropolitan Institute of Gerontology Index of Competence (TMIG Index of Competence) were measured. The reliability of this scale was examined using Cronbach's alpha, and test-retest correlation. The criterion-related validity and the construct validity were evaluated relatively using physical functions and factor analysis. The score was compared between young-old and old-old and gender. The correlation between SEPAF and TMIG Index of Competence was examined.

RESULTS

Cronbach's a showing internal consistency for these scales were 0.78-0.82. The score showed significant differences in gender and age group. There were significant relationships between SEPAF and physical functions, and the TMIG Index of Competence.

CONCLUSION

The SEPAF was shown to be highly reliable. Few scale for frail elderly people exist, and it is useful to assess the self-efficacy of physical activities in frail and community-dwelling elderly people.

The usefulness of a continuous administration of tirapazamine combined with reduced dose-rate irradiation using {gamma}-rays or reactor thermal neutrons

We clarified the usefulness of the continuous administration of tirapazamine (TPZ) in combination with reduced dose-rate irradiation (RDRI) using gamma-rays or reactor thermal neutrons. Squamous cell carcinoma (SCC) VII tumour-bearing mice received a continuous administration of 5-bromo-2'-deoxyuridine (BrdU) to label all proliferating (P) cells. Then, they received a single intraperitoneal injection or 24 h continuous subcutaneous infusion of TPZ in combination with conventional dose-rate irradiation (CDRI) or RDRI using gamma-rays or thermal neutrons. After irradiation, the tumour cells were isolated and incubated with a cytokinesis blocker, and the micronucleus (MN) frequency in cells without BrdU labelling ( = quiescent (Q) cells) was determined using immunofluorescence staining for BrdU. The MN frequency in the total tumour cells was determined using tumours that were not pre-treated with BrdU. The sensitivity of both total and Q cells, especially of Q cells, was significantly reduced with RDRI compared with CDRI. Combination of TPZ increased the sensitivity of both populations, with a slightly more remarkable increase in Q cells. Furthermore, the continuous administration of TPZ raised the sensitivity of both total and Q cell populations, especially the former, more markedly than the single administration, whether combined with CDRI or RDRI using gamma-rays or thermal neutrons. From the viewpoint of solid tumour control as a whole, including intratumour Q-cell control, the use of TPZ, especially when administered continuously, combined with RDRI, is useful for suppressing the reduction in the sensitivity of tumour cells caused by the decrease in irradiation dose rate in vivo.

Role of homologous recombination in the alpha-particle-induced bystander effect for sister chromatid exchanges and chromosomal aberrations

The bystander effect for sister chromatid exchanges (SCEs) and chromosomal aberrations was examined in hamster cell lines deficient in either DNA-PKcs (V3 cells, deficient in nonhomologous end joining, NHEJ) or RAD51C (irs3 cells, deficient in homologous recombination, HR). Cells synchronized in G0/G1 phase were irradiated with very low fluences of alpha particles such that < 1% of the nuclei were traversed by an alpha particle. Wild-type cells showed a prominent bystander response for SCE induction; an even greater effect was observed in V3 cells. On the other hand, no significant induction of SCE was observed in the irs3 RAD51C-deficient bystander cells irradiated at various stages in the cell cycle. Whereas a marked bystander effect for chromosomal aberrations occurred in V3 cells, the induction of chromosomal aberrations in irs3 bystander cells was minimal and similar to that of wild-type cells. Based on these findings, we hypothesize that HR is essential for the induction of SCE in bystander cells; however, HR is unable to repair the DNA damage induced in NHEJ-deficient bystander cells that leads to either SCE or chromosomal aberrations.

Development of a practical immunochromatographic test with recombinant P50 for the diagnosis of Babesia gibsoni infection in dogs

An immunochromatographic test (ICT), using recombinant truncated P50 (P50t), for the detection of antibodies to Babesia gibsoni was developed and evaluated. Whereas all sera from specific pathogen-free dogs were clearly negative, all sera from dogs experimentally infected with B. gibsoni were clearly positive in the ICT. In addition, the ICT detected no cross-reactivity with sera from dogs experimentally infected with closely related parasites, B. canis canis, B. canis vogeli, and B. canis rossi, or with Neospora caninum, and Leishmania infantum. Sequential sera from a dog experimentally infected with B. gibsoni were tested with the ICT; it was shown that the specific antibodies are detectable as early as 6 days post-infection (p.i.) and that strong antibody responses remained until the end of the experiment (144 days p.i.). To evaluate the clinical application of the ICT, a total of 54 serum samples collected from domestic dogs that had been identified as having signs of anaemia at veterinary hospitals in Japan, were tested with the ICT, the previously established enzyme-linked immunosorbent assay (ELISA) and with the indirect fluorescent antibody test (IFAT). Twenty-four of the tested samples (44.4%) were positive in both ICT and ELISA, and (51.8%) in IFAT. The concordance between ELISA and ICT was found to be 100%, and 85.7% with IFAT. Taken together, the results above suggest that the ICT using P50t is rapid, simple, accurate, and suitable for use at clinical sites for the diagnosis of B. gibsoni infection in dogs.

Toxoplasma gondii antigens GRA1 (p24) and SAG1 (p30): a comparison of their stimulatory influence on T-cell activation and cytokine expression in in vitro cultures

The influence of recombinant cell surface SAG1 (rp30) and secretory GRA1 (rp24) antigens (Ag) on T-cell activation and cytokine induction in vitro was compared. T-cell activity and the level of IFN-gamma, IL-10 and IL-12 expression in rp30-immunized T cells were considerably increased in the presence of rp30 Ags. IgG2a and IgG1 antibodies (Ab) were detected in sera of rp24- and rp30-immunized mice, with the secretory rp24 Ag having induced significantly higher titer of IgG1 Ab. In vitro, the greater antigenicity of surface rp30 Ag was notable based on the level of T-cell activation, and cytokine synthesis suggestive of the participation of Th1 cells. Although, IFN-gamma expression by rp24 Ag was lower compared to rp30 Ag, the synthesis of both IgG2a and IgG1 Abs reflects the protective nature of rp24 Ag. We have generated two recombinant Toxoplasma gondii Ags that demonstrated differences in antigenicity in vitro. It would be interesting to evaluate the mechanism(s) of immunity induced by SAG1 (p30) and GRA1 (p24) Ags against infection with T. gondii in vivo.