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Temperature-dependent FTIR spectra of linoleic acid were measured over a temperature range of -80 to -30 °C to explore solid-state low-temperature (LT) → middle-temperature (MT) phase transition of linoleic acid. Band assignments were made mainly for the 900-760 cm(-1) region, where the bands due to cis-olefin group's ═C-H out-of-plane mode and the progression bands due to CH(2) rocking-CH(2) twisting modes are expected to appear. The structural evolutions during the LT → MT phase transition of linoleic acid were investigated by analyzing the progression bands with the simple-coupled oscillator model to elucidate the features of acyl chain influenced with two cis-C═C bonds linked through one CH(2) group. Structure changes in the LT → MT transition of linoleic acid were compared with those in the γ → α transition of oleic acid. It has been found that the former is rather localized around the cis-diene group, while the latter occurs in the larger portion between the cis-olefin group to the methyl end. It is also suggested that the conformational change in the cis-olefin group on the LT → MT transition is on a lesser scale than that on the γ → α transition., (© 2011 American Chemical Society)

In previous studies we have shown that the linear energy transfer (LET)-relative biological effectiveness (RBE) curves were affected by LET and ion species [1,2]. In this paper we have examined the difference in the repair kinetics of G1-prematurely condensed chromosome breaks in normal human fibroblasts following irradiation with different heavy-ion beams of similar LET values. Normal human fibroblasts were irradiated with about 110 keV/microm of carbon (135 MeV/n), neon (400 MeV/n) and silicon ions (490 MeV/n), and the doses of carbon (3.25 Gy), neon (2.94+/-0.01 Gy) and silicon (2.31 Gy) were chosen to produce approximately the same number of initially measured G1-premature chromosome condensation (PCC) breaks (about 37 excess fragments per cell). The number of G1-PCC breaks was counted as excess fragments of prematurely condensed chromosomes using the PCC technique in the G1/G0 phase. The fractions of residual G1-PCC breaks after 24 h post-irradiation and half time, which is the time point where 50% of initially measured G1-PCC breaks are rejoined (t1/2), of the slow components of rejoining in carbon- and neon-ion irradiated cells were different from those of silicon-ion irradiated cells. However, no difference was observed in the half time of the fast components of rejoining in each ion beam. The results suggest that the difference in the fractions of residual G1-PCC breaks after 24 h post-irradiation reflect the result of the slow repair process for induced G1-PCC breaks, and that the repair process is dependent on the ion species, not the LET values., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

This study aimed to clarify the regulatory mechanism of Mg homeostasis on administration of excessive Mg in rats. Six-week-old male Wistar rats (n=30) were fed a Mg-deficient diet (D) or a control diet (M) in addition to which they received subcutaneous injections of saline (S) or additional Mg (M) for 14 d. Feces and urine were collected from the rats for 4 d every week. Between the MS and MM rats and the DS and DM rats, the injection of additional Mg increased Mg retention, but intestinal Mg absorption did not differ. Urinary Mg excretion in the MM rats was significantly greater than that in the MS rats, but fecal Mg excretion did not increase. Mg retention in the DM rats was approximately 30% of that in the MS rats, and urinary Mg excretion did not differ between the 2 groups, although the serum Mg in DM rats was low. There was no significant difference in the femoral Mg between the MM and MS groups. The physiological Mg pool in the bone appears to be limited. Therefore, there is no physiological Mg pool for the storage of excessive Mg, and there appears to be no negative feedback mechanism on intestinal Mg absorption upon administration of excessive Mg in the rats. In conclusion, it appears that the kidney is the only organ that regulates Mg in the body; apart from this, regulatory mechanisms corresponding to the physiological Mg requirement do not exist or are weak.

We investigated the influence of low-dose, low-dose-rate gamma-ray irradiation on DNA double strand break (DSB) repair in human lymphoblastoid TK6 cells. A single DSB was introduced at intron 4 of the TK+ allele (chromosome 17) by transfection with the I-SceI expression vector pCBASce. We assessed for DSB repair due to non-homologous end-joining (NHEJ) by determining the generation of TK-deficient mutants in the TK6 derivative TSCE5 (TK +/-) carrying an I-SceI recognition site. We similarly estimated DSB repair via homologous recombination (HR) at the same site in the derived compound heterozygote (TK-/-) cell line TSCER2 that carries an additional point mutation in exon 5. The NHEJ repair of DSB was barely influenced by pre-irradiation of the cells with 30 mGy gamma-rays at 1.2 mGy h(-1). DSB repair by HR, in contrast, was enhanced by approximately 50% after pre-irradiation of the cells under these conditions. Furthermore, when I-SceI digestion was followed by irradiation at a dose of 8.5 mGy, delivered at a dose rate of only 0.125 mGy h(-1), HR repair efficiency was enhanced by approximately 80%. This experimental approach can be applied to characterize DSB repair in the low-dose region of ionizing radiation.

Objective: Magnification by surgical loupes has the distinct merits of agility and nimbleness in observation, a wide stereo base effectuating superior depth sensation, and light augmentation by an objective lens that is larger than the pupil. However, continuous use of these loupes causes neck strain for surgeons as a result of flexion posture and fatigue. To minimize the strain and fatigue and maximize the advantages and performance of binocular telescopes, we have developed a novel optical design., Methods: To allow observation of the operative field with the surgeon's neck and eye in a straight position, the light path of the telescopes was angulated downward with roof prisms. For maximum image quality, Keplerian real-image optics were adopted., Results: The optics, finishing of the lens, and assembly were perfected through practical trials of more than 500 procedures over a period of 3 years., Conclusion: The new ergonomically designed optics provide excellent image quality comparable to standing microscopes in the low to medium range of magnification, while effectively reducing the neck flexion of surgeons working in the operative field below and relieving the surgeon's fatigue during hours of continuous use.

Dynamical properties of acyl chains in the three polymorphic phases alpha, beta', and beta of tristearin [C(3)H(5)(OCOC(17)H(35))3] have been studied by means of incoherent quasielastic neutron scattering (IQNS) using selectively deuterated samples. The mean square displacement of hydrogen atoms, , was estimated from the scattering vector Q dependence of the elastic scattering component under the harmonic approximation. It was shown that the temperature dependence of was significantly different between the three phases. There was no marked difference in between these phases up to 193 K, and the value increased linearly with temperature. Although the beta phase remained linear up to 293 K, the alpha and beta' phases started to show a nonlinear increase around 200 K, suggesting an anharmonic nature of molecular motions. The alpha phase exhibited the most conspicuous temperature dependence. These characteristics were ascribable to the difference in the lateral packing of acyl chains. Compared with the beta phase which has a tightly packed T// subcell, the beta' and alpha phases have looser O perpendicular and H subcells, respectively. The molecular motion in the alpha phase was analyzed using the model of uniaxial rotational diffusion in a onefold cosine potential. It has been clarified that the rotational fluctuation about the chain axis in the alpha phase is rather restricted compared with that in the rotator phase of n-alkanes.

It has been empirically known that cholesterol largely increases the viscosity of oleic acid. To clarify the mechanism of the effect of cholesterol on the intermolecular and the intramolecular (segmental) movements of oleic acid in the liquid state, we measured density, viscosity, IR, 1H NMR chemical shift, self-diffusion coefficient, and 13C NMR spin-lattice relaxation time for the liquid samples of oleic acid containing a small amount of cholesterol. Furthermore, the above measurements were also carried out for the samples of oleic acid containing a small amount of cholestanol, cholestane, cholesteryl oleate, ethanol, or benzene. Cholesterol, possessing one OH group and one double bond in its molecular structure, largely increased the viscosity and reduced the self-diffusion and the intramolecular movement of oleic acid. Cholestanol, possessing one OH group but not a double bond, and cholesteryl oleate, not possessing an OH group, also reduced the self-diffusion and the intramolecular movement; cholestane, not possessing an OH group, slightly reduced the self-diffusion and the intramolecular movements. In contrast with these sterols, ethanol and benzene reduced the viscosity and increased the self-diffusion and the intramolecular movements. In addition, cholesterol and ethanol, both having one OH group, promoted the upfield shift of the 1H NMR signal of the carboxyl group of oleic acid; IR difference spectra for the cholesterol/oleic acid system quite resemble those for the ethanol/oleic acid system. These results suggest that oleic acid makes a complex with cholesterol as well as with ethanol. On the basis of the formation of the complex, we have revealed the role and the functional mechanism of cholesterol to the intermolecular and the intramolecular movements of oleic acid in the liquid state.

The aim of this study was to identify potential biomarkers for radiosensitivity using the relationship between cell killing and the yield of excess chromatin fragments detected with the premature chromosome condensation (PCC) technique. This method was applied to primary cultured cells obtained from biopsies from patients. Six primary culture biopsies were obtained from 6 patients with carcinoma of the cervix before starting radiotherapy. The cultures were irradiated with two different LET carbon-ion beams (LET = 13 keV/microm, 77.1+/-2.8 keV/microm) and 200 kV X-rays. The carbon-ion beams were produced by Heavy Ion Medical Accelerator in Chiba (HIMAC). PCC was performed using the polyethylene glycol-mediated cell fusion technique. The yield of excess chromatin fragments were measured by counting the number of unrejoined chromatin fragments detected with the PCC technique after a 24-h post-irradiation incubation period. Obtained results indicated that cultures which were more sensitive to killing were also more susceptible to the induction of excess chromatin fragments. Furthermore there was a good correlation between cell killing and excess chromatin fragments among the 6 cell cultures examined. There is also evidence that the induction of excess chromatin fragments increased with increasing LET as well as cell-killing effect in the same cell culture. The data reported here support the idea that the yield of excess chromatin fragments detected with the PCC technique might be useful for predicting the radiosensitivity of cells contained in tumor tissue, and to predict responses to different radiation types.

Chronic obstructive pulmonary disease (COPD) involves a decrease in respiratory function and limits daily activities. We report a COPD patient whose respiratory symptoms were improved by acupuncture treatment. A 66-year-old man visited Gifu University Hospital with breathlessness on exercise. Despite medication, his general condition worsened. A series of acupuncture treatments was subsequently started on October 27, 2001. He had level III breathlessness on JRS classification prior to acupuncture treatment, and his respiratory function parameters were VC: 3.54 L, FEV1: 1.19 L, FEV1% (G): 33.6% and %FEV1: 45%. The basic meridian points used were KI 3 (Fuliu), LU 9 (Taiyuan), LU 1 (Zhongfu), CV 12 (Zhongwan), CV 4 (Guanyuan), BL 13 (Feishu), and BL 23 (Shenshu). The acupuncture needles were retained for ten minutes in each session. This research design was used to detect the specific efficacy of acupuncture treatment After ten acupuncture treatments over two months, his walking distance, Borg scale and respiratory function were improved compared with before treatment. These findings suggest that acupuncture treatment may be efficacious for advanced cases of COPD.

Two immortalized human airway epithelial cell lines were established by the ectopic expression of human telomerase reverse transcriptase (hTERT). These cell lines have been continuously cultured for >200 population doublings (PDs). They are characterized by an overexpression of hTERT mRNA, elongated telomere length and higher telomerase activity. Early passage of these cells (<20 PDs) expressed the p16 protein at a level comparable to their parental cells. In later passages (>150 PDs), p16 protein was decreased but recovered to the early passage level upon treatment with a methylation inhibitor, 5-Aza-CdR. Chromosome analysis showed a near-diploid karyotype albeit with a gain or loss of certain chromosomes and a few stable translocations in both cell lines. No p53 gene alterations were found in these cell lines. They remained anchorage dependent in growth and were non-tumorigenic in nude mice. These two cell lines are the first reported immortalized human airway epithelial cell lines by hTERT expression without incorporation of virus or other genes, which may serve as a useful model system for studies on bronchial carcinogenesis.

Radiation-induced damage to living cells results from either a direct hit to cellular DNA, or from indirect action which leads to DNA damage from radiation produced radicals. However, in recent years there is evidence that biological effects such as cell killing, mutation induction, chromosomal damage and modification of gene expression can occur in a cell population exposed to low doses of alpha particles. In fact these doses are so low that not all cells in the population will be hit directly by the radiation. Using a precision alpha-particle microbeam, it has been recently demonstrated that irradiated target cells can induce a bystander mutagenic response in neighboring "bystander" cells which were not directly hit by alpha particles. Furthermore, these results suggest that gap-junction mediated cell-to-cell communication plays a critical role in this bystander phenomenon. The purpose of this section is to describe recent studies on bystander biological effects. The recent work described here utilized heavy charged particles for irradiation, and investigated the role of gap-junction mediated cell-cell communication in this phenomenon.

We have been studying LET and ion species dependence of RBE in mutation frequency and mutation spectrum of deletion pattern of exons in hprt locus. Normal human skin fibroblasts were irradiated with heavy-ion beams, such as carbon- (290 MeV/u and 135 MeV/u), neon- (230 MeV/u and 400 MeV/u), silicon- (490 MeV/u) and iron- (500 MeV/u) ion beams, generated by Heavy Ion Medical Accelerator in Chiba (HIMAC) at national Institute of Radiological Sciences (NIRS). Mutation induction in hprt locus was detected to measure 6-thioguanine resistant colonies and deletion spectrum of exons was analyzed by multiplex PCR. The LET-RBE curves of mutation induction for carbon- and neon-ion beams showed a peak around 75 keV/micrometers and 155 keV/micrometers, respectively. On the other hand, there observed no clear peak for silicon-ion beams. The deletion spectrum of exons was different in induced mutants among different ion species. These results suggested that quantitative and qualitative difference in mutation occurred when using different ion species even if similar LET values.

We examined the potential contribution of irradiated medium on the bystander effect using custom made double-mylar stainless steel rings. Exponentially growing Human-hamster hybrid (AL) cells were plated on either one or both sides of double-mylar dishes 2-4 days before irradiation. One side (with or without cells) was irradiated with alpha particles using the track segment mode of a 4 MeV Van de Graaff accelerator at the Radiological Research Accelerator Facilities of Columbia University. Since alpha particles can only traverse a very limited distance, cells plated on the other side of a medium-filled mylar dish will not be irradiated by the alpha particles. The results of chromosomal aberrations on un-irradiated target cells that were attached to the top mylar layer indicate that the number of chromatid-type aberrations was higher when there was a bottom layer of cells in the medium filled chambers than just medium alone. Furthermore, when transferring the medium from these cell-irradiated dishes to fresh AL cultures, chromatid-type aberrations were produced in the un-irradiated fresh cells. In contrast, medium irradiated in the absence of cells had no effect on chromatid aberrations. These results suggest that certain modulating factors secreted from the irradiated cells on the bottom mylar layer into the medium, induce chromatin damage in the un-irradiated, bystander cells.

Multiple-chemical sensitivity (MCS) patients are presumed to be compelled to lead inconvenient and difficult lives, because unpleasant and multiorgan symptoms are caused by very small amounts of various chemicals in the living environment. Therefore we conducted a questionnaire survey of MCS patients who are members of support groups to elucidate the problems of MCS patients in using medicinal drugs. In this report, we selected 205 persons who stated that they had been "diagnosed with MCS by a physician" or "a physician suspected a diagnosis of MCS" on the questionnaire as the reason they judged themselves to have MCS. The questionnaire results showed that about 60% of MCS patients have difficulty in using medicinal drugs and that the difficulties are more likely to occur in women, in people 40-59 years old, and in patients who developed MCS in reaction to pesticides or medicinal drugs. The prescribed drugs and OTC drugs noted as usable or unusable by patients in the questionnaire were analyzed from the viewpoint of their medicinal constituents. The results indicated that lidocaine is likely to be unusable by MCS patients. In addition, caffeine, aspirin, chlorphenylamine maleate, minocycline hydrochloride, levofloxacin, etc. were also likely to be unusable by MCS patients. Many patients who recorded drugs containing the above-mentioned remedies as unusable had a past history of allergy, suggesting that allergy is involved in the difficulties of MCS patients in using medicinal drugs.

We investigated the difference in cell-killing effect and mutation induction between carbon- and neon-ion beams in normal human cells. Carbon- and neon-ion beams were accelerated by the Riken Ring Cyclotron (RRC) at the Institute of Physical and Chemical Research in Japan. Cell-killing effect was measured as the reproductive cell death using the colony formation assay. Mutation induction at the HPRT locus was detected to measure 6-thioguanine-resistant clones. The mutation spectrum of the deletion pattern of exons of induced mutants was analyzed using the multiplex polymerase chain reaction (PCR). Cell-killing effect was almost the same between carbon- and neon-ion beams with similar linear energy transfer (LET) values, while there observed a large difference in mutation frequency. Furthermore, in the case of neon-ion beams 60% of mutants showed total deletions and 35-40% showed partial deletions, while 95-100% of carbon-ion induced mutants showed total deletions. The results suggest that different ion species may cause qualitative and quantitative difference in mutation induction even if the LET values are similar.

We report here a bystander effect in chromosomal damage using He-ion microbeam. Human-hamster hybrid cells were irradiated with a precision He-ion microbeam generated by the Columbia microbeam system. When 20% of the cells were exposed to single He ion, the incidence of cells with chromatid-type breaks detected with the PCC technique was covered wide range from 0 to 6 breaks per cell. In contrast, the distribution showed a mixed two-peak pattern, such as non-exposed and all-cell exposed patterns, under the condition of assuming no bystander effect by treating with an effective inhibitor of cell-cell communication. These findings provide clear evidence that single He-ion irradiated cells can induce bystander chromosomal alterations in neighboring cells not directly hit by He ion.

We have been studying LET and ion species dependence of RBE values in cell killing and mutation induction. Normal human skin fibroblasts were irradiated with heavy-ion beams such as carbon (290 Mev/u and 135 Mev/u), neon (230 Mev/u and 400 Mev/u), silicon (490 Mev/u) and iron (500 Mev/u) ion beams, generated by Heavy Ion Medical Accelerator in Chiba (HIMAC) at National Institute of Radiological Sciences (NIRS). Cell killing effect was detected as reproductive cell death using a colony formation assay. Mutation induction in hprt locus was detected to measure 6-thioguanine resistant colonies. The RBE-LET curves of cell killing and mutation induction were different each ion beam. So, we plotted RBE for cell killing and mutation induction as function of Z*2/beta2 instead of LET. RBE-Z*2/beta2 curves of cell killing indicated that the discrepancy of RBE-LET curves was reconciled each ion species. But RBE-Z*2/beta2 curves of mutation induction didn't corresponded between carbon- and silicon-ion beams. These results suggested that different biological endpoints may be suitable for different physical parameter, which represent the track structure of energy deposition of ion beams.

The present study was undertaken to know the effect of supplementation of fish oil with high n-3 polyunsaturated fatty acids (PUFA) on oxidative stress-induced DNA damage of rat liver in vivo. Male Wistar rats were fed a diet containing fish oil or safflower oil with high n-6 PUFA at 50 g/kg of diet and an equal amount of vitamin E at 59 mg/kg of diet for 6 weeks. Livers of rats fed fish oil were rich in n-3 PUFA, whereas those of rats fed safflower oil were rich in n-6 PUFA. Ferric nitrilotriacetate was intraperitoneally injected to induce oxidative stress. The degree of lipid peroxidation of the liver was assessed by the levels of phospholipid hydroperoxides and thiobarbituric acid-reactive substances (TBARS), and the degree of oxidative DNA damage was assessed by comet type characterization in alkaline single-cell gel electrophoresis and 8-hydroxy-2'-deoxyguanosine levels. The levels of TBARS of the livers of the fish oil diet group increased to a greater extent than those of the safflower oil diet group, whereas the levels of the hydroperoxides of the livers of both diet groups increased to a similar extent. The vitamin E level of livers of the fish oil diet group was remarkably decreased. The degree of DNA damage of both diet groups was increased, but the increased level of the fish oil diet group was remarkably lower than that of the safflower oil diet group. The above results indicate that fish oil supplementation does not enhance but appears to protect against oxidative stress-induced DNA damage and suggest that lipid peroxidation does not enhance but lowers the DNA damage.

The effect of supplementation of n-3 polyunsaturated fatty acids (PUFA) on oxidative stress-induced DNA damage of rat hepatocytes was examined. Male Wistar rats were fed a diet containing safflower oil (control n-6 PUFA diet) or fish oil (n-3 PUFA diet) in 50 g/kg of dried diet and an equal amount of vitamin E in 59 mg/kg of dried diet for 6 weeks. The liver of rats fed safflower oil was rich in n-6 PUFA, whereas that of rats fed fish oil was rich in n-3 PUFA. Isolated hepatocytes were treated in vitro with ADP/Fe (II) ion or hydrogen peroxide at 37 degrees C for 30 min to induce oxidative stress. The degree of lipid peroxidation was assessed by the levels of phospholipid hydroperoxides and thiobarbituric acid-reactive substances. The degree of oxidative DNA damage was assessed based on comet-type characterization in alkaline single-cell gel electrophoresis and 8-hydroxy-deoxyguanosine levels. In both ADP/Fe(II) ion and hydrogen peroxide oxidation, the degree of lipid peroxidation of hepatocytes increased in both diet groups, and the level of increase in the fish oil diet group was slightly higher than that in the safflower oil diet group. In ADP/Fe(II) ion oxidation, the degree of DNA damage increased in both diet groups, but there were no significant differences in the level of increase. In contrast, in hydrogen peroxide oxidation, the degree of DNA damage increased in both diet, and the increase in the fish oil diet group was significantly lower than that in the safflower oil diet group. It is unlikely that an n-3 PUFA-rich diet enhances oxidative stress-induced hepatocyte DNA damage as compared with the control n-6 PUFA-rich diet.

Seven patients with ischemic cardiomyopathy who underwent elective endoventricular circular patch plasty (EVCPP) were included in this study. The mean age of the patients at the time of surgery was 63 years old. All seven patients had anterior left ventricular aneurysms following old myocardial infarction. Two patients were graded NYHA class II, 4 patients class III, and one patient class IV. EVCPP was performed under cardiac arrest with moderate hypothermia in five patients. The two most recent patients underwent EVCPP under on-pump beating and normothermia. Coronary artery bypass grafting was conducted in all cases and the mean number of grafts was 1.8, ranging from one to three. The mitral valve was replaced in one patient. One patient died of myonephrotic metabolic syndrome caused by ischemia of the lower limb. In the follow-up of six patients, the left ventricular end-diastolic volume index (LVEDI) decreased significantly from 128 +/- 31 mL/ m2 to 108 +/- 37 mL/m2. Left ventricular end-systolic volume index (LVESI) decreased in five patients. Left ventricular end-diastolic and end-systolic diameter remained unchanged after surgery. The left ventricular ejection fraction (LVEF) increased from 0.28 +/- 0.08 to 0.321 +/- 0.1. LVESI and LVEF did not improve in one patient with a large residual dyskinetic area at the distal LV septum. A residual dyskinetic area at the distal LV septum was observed in two of four patients who underwent EVCPP under cardiac arrest. This condition, however, was not detected in two patients who underwent EVCPP under on-pump beating conditions. In the follow-up study, the grade of NYHA functional classification improved in all six patients. In conclusion, EVCPP under on-pump beating is a realistic and effective procedure with which to complete ideal LV geometry and promote good results in patients with ischemic cardiomyopathy.