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In the rat, activation of the intracerebral cholinergic system originating in the basal forebrain and projecting to the cortex and hippocampus releases acetylcholine in the cortex and hippocampus, which results in vasodilation and an increase in regional cerebral blood flow (rCBF) in the cortex and hippocampus. The augmentation of rCBF is independent of both systemic blood pressure and regional metabolism. The intracerebral cholinergic fibers are able to act as autonomic nerve fibers for the regulation of cortical and hippocampal blood flow. [Copyright &y& Elsevier]

Examines the field performance of a high-resolution nuclear magnetic resonance superconducting magnet. Persistent-mode operation of the magnet; Field decay; Field homogeneity.

This article reviews the study of neural vasodilator mechanisms of the cerebral cortex by basal forebrain cholinergic nerve fibers and their age-related function in rats. During the last decade, we have demonstrated a neural regulatory system of cerebral blood flow in rats involving intracerebral cholinergic vasodilator nerve fibers originating in the basal forebrain and projecting to the cerebral cortex. Activation of these cholinergic vasodilator fibers results in the release of acetylcholine (ACh) within the cortex, activation of both nicotinic and muscarinic ACh receptors, and vasodilatation without coupling to glucose metabolic rates. This cholinergic vasodilator system has been shown to decline with age in rats mainly due to age-related declines of nicotinic ACh receptor activity. However, muscarinic ACh receptor activity and the release of ACh into the extracellular space in the cortex are well maintained during aging. The present age-related decline of the intracerebral cholinergic vasodilator system found in rats seems to affect cognitive function during aging, although this cholinergic vasodilator system has not yet been demonstrated in humans. [Copyright &y& Elsevier]

Describes the superconducting NMR magnet developed at the Tsukuba Magnet Laboratory in Japan in 1999. Manufacture of the magnet with 15-percent tin-bronze-processed (Nb,Ti)[sub 3]Sn, Tantalum-reinforced (Nb,Ti)[sub 3]Sn and NbTi conductors; Cooling of coils used with pressurized superfluid helium.

A number of clinical studies have suggested that radiant heat improves the healing of selected acute and chronic wounds. The purpose of this study was to investigate in vitro the effect of intermittent radiant heating on the growth of human skin fibroblasts using a radiant heat-producing dressing with a designated temperature of 38 °C. In initial experiments cells were seeded in six well-plates, maintained in culture at 33–34 °C, and warmed daily for three cycles of 1 hour with 1.5 hour intervals. Changes in cell growth and metabolism were determined in sets of triplicate wells by cell counts and a colorimetric assay before and after one week's treatment, After eight days the number of cells indings suggest that the stimulation of cell proliferation induced by intermittent heating in vitro may indicate a possible mechanism contributing to in vivo effects. (WOUND REP REG 2000;8:138–144). [ABSTRACT FROM AUTHOR]

Presents results of the engineering design and research and development studies on candidate superconductors for the inner coil of a one GHz superconducting nuclear magnetic resonance magnet at the Tsukuba Magnet Laboratory of the National Research Institute for Metals in Japan. Outer magnet and inner coils of the low temperature superconductor coils. generation.

We report liquid/air partition coefficients for dilute solutions of acetaldehyde in water, saline (0.9% wt/vol NaCI), human plasma, and com oil. Equilibrium was studied at 34°C and 37°C with various concentrations of acetaldehyde in the liquid phases. At 37°C, the liquid/air partition ratios for water, saline, plasma, and oil were 143 ± 7.1,132 ± 6.6,183 ± 3.6, and 64 ± 9.9 (means ± SE), respectively. At 34°C, all the values were higher and the temperature coefficients of solubility were 3.7%, 3.3%, and 4.0% per 1°C for water, saline, and plasma solutions of acetaldehyde, respectively. The partition coefficients were independent of the concentration of acetaldehyde in the liquids, and the solubility was higher in water than in oil. The results are discussed with emphasis on the usefulness of expired breath as a biological specimen for the quantitative determination of acetaldehyde. [ABSTRACT FROM AUTHOR]

Examines the relationship between pneumatosis cystoides intestinalis (PCI) and trichloroethylene in Japan. Occurrence of PCI among females; Infection on large intestines and sigmoid colon; Analysis of trichloroethylene exposure.

To realize high-capacity wireless access, the millimeter-wave frequencies have been investigated. Research on indoor multipath propagation has been pursued intensively. This paper proposes an evaluation method for the millimeter-wave indoor high-capacity digital transmission characteristics. First, the broadband propagation characteristics under indoor multipath environment were measured so that the multiple-wave configurations are clarified. Next, to quantify the digital transmission characteristics under the multiple wave environment, the level ratio (D/U) of the desired wave to the interference wave was evaluated for a bit error rate of 10-4 by means of a 4 PSK- 100 Mb/s and a multipath fading simulator. It was found that the bit error rate is determined by the level ratio (D/UT) of the desired wave to the total interference waves and not by the delay time of the interference wave if the delay time of the interference wave exceeds the symbol duration and that the desired D/UT approaches the signal-to-noise (S/N) ratio (N: Gaussian noise) giving such a bit error rate. From the foregoing results, this paper proposes a channel design method using the D/U in indoor high-capacity wireless communication. [ABSTRACT FROM AUTHOR]

Examines the structure-activity relationship of chlorinated hydrocarbons. Determination of partition coefficients; Interrelation between coefficients and toxicity of hydrocarbons; Use of gas chromatographic equilibration method in determining the coefficient partition.

It is desirable that the method used for outdoor path loss estimation at microwave frequencies be one for which a worldwide consensus can be obtained through an ITU-R international standard. In this paper, a path loss prediction model for over-rooftop propagation environments is proposed for suburban areas. This model is based on the propagation mechanism explained by using the geometrical optics and consists of the direct wave region, the reflected wave region, and the diffracted wave region. The boundary points of these regions can be determined uniquely from the antenna height and building environment and all regions are continuously connected. Hence, high-precision estimation of the path loss can be estimated from the short-distance line-of-sight region to the far-field non-line-of-sight region. The proposed model is useful for channel design of microwave-band wireless access systems. Further, the method contributes to the ITU-R international standardization described above. Finally, it is shown that the measured path loss and the value estimated by the present model agree well at 2.2, 5.2, and 19.4 GHz. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 90(1): 13–24, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20333 [ABSTRACT FROM AUTHOR]

5-GHz-band wireless access systems, such as the RLAN (Radio Local Area Network) system of IEEE 802.11a, HiperLAN/2, HiSWANa, and AWA, are deployed for indoor use at transmission rates over 20 Mbps. These 5-GHz access systems are expected to extend service areas from the office to the so-called “hot spots” in public areas. Underground shopping malls are one type of service area where the application of such nomadic wireless access service can be expected. In order to design radio zone configurations, it is necessary to know broadband propagation characteristics of an underground mall environment even if results obtained by previous measurements in the narrow band are available. This paper presents results of an experimental study on the propagation characteristics for broadband wireless access systems in an underground mall environment. First, broadband propagation path losses are measured and formulated considering the shadowing by human body. A ray trace simulation is used to clarify the basic propagation mechanism in such a closed environment. Next, it was determined that values of the delay spread at different distances during rush hour periods did not exceed 65 ns, which is lower than the permitted maximum value of the present 5-GHz systems. The final conclusion is that the above propagation characteristics corroborate results of transmission tests carried out by using the AWA equipment. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(3): 55–64, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20059 [ABSTRACT FROM AUTHOR]

As a milestone in the 1-GHz NMR magnet project that is being carried out at the Tsukuba Magnet Laboratory (TML), a 920-MHz high-resolution NMR magnet was successfully manufactured. It is made of 15%Sn-bronze-processed (Nb, Ti)aSh, Ta-reinforced (Nb, Ti)[sub 3]Sn, and NbTi conductors. The room-temperature bore of the cryostat is 54 mm in diameter. All the coils are cooled with pressurized superfluid helium at 1.55 K. The magnet was moved to a new building of the TML in December 2001. A persistent operation at 920 MHz started in April 2002. The field homogeneity after correcting with superconducting shim coils was less than 0.1 ppm in a sample volume. Field decay decreased to below 1.3 Hz/h at the beginning of July. NMR measurements using this magnet started in July. [ABSTRACT FROM AUTHOR]

The effect of high carbohydrate (hc) diet on glucose tolerance and on lipid profiles in patients with type 2 diabetes mellitus is contradicted. Japanese patients with mild type 2 diabetes mellitus were allocated either 55% standard carbohydrate (sc) or 80% high carbohydrate diets for 1 week, and OGTT and lipid profiles were examined. Then the diet was crossed over for another week, and OGTT and other identical parameters were re-evaluated. High carbohydrate diet improved the area under the glucose concentration–time curve (AUG) in 16/24 patients, and significantly increased and decreased 1,5-anhydroglucitol and homeostasis model assessment insulin resistance (HOMA-R) as a whole, respectively. Fasting plasma glucose (FPG) hc/sc ratio was inversely correlated with HOMA-R on a standard carbohydrate diet. High carbohydrate diet significantly decreased LDL- and HDL-cholesterol, whereas it significantly increased triglyceride. Furthermore, hc/sc ratios of the lipid parameters were inversely correlated with the respective parameters on standard carbohydrate diet. The present study indicates that high carbohydrate diet improved glucose tolerance depending on patients and the improvement in FPG was predicted by HOMA-R on a standard carbohydrate diet. The effect of high carbohydrate diet on glucose tolerance and lipid profiles should be investigated through a long-term study in the future. [Copyright &y& Elsevier]

In mammals, organ induction occurs only during embryonic development except for hair follicles (HFs). However, HF-resident epithelial stem cells (HFSCs), which are responsible for repetitive HF regeneration, are not fully characterized. Here, we establish in vitro culture systems that are capable of controlling the ability of HFSCs to regenerate HFs. Based on a method that precisely controlled the number of HFs for regeneration, functional analysis revealed that CD34/CD49f/integrin β5 (Itgβ5)-triple-positive (CD34+/CD49f+/Itgβ5+) cells have multipotency and functional significance for continual hair regeneration. In native HFs, these cells reside in the uppermost area of the bulge region, which is surrounded by tenascin in mice and humans. This study unveils the subpopulation of HFSCs responsible for long-term hair cycling of HFs regenerated from bioengineered HF germ, suggesting the presence of functional heterogeneity among bulge HFSCs and the utility of our culture system to achieve HF regenerative therapy. [ABSTRACT FROM AUTHOR]

Abstract: Background: Breast cancer has become the most common cancer among women worldwide. Although the consumptions of milk and dairy products were considered to be a risk factor for breast cancer in some epidemiological studies, the results were inconsistent. Methods: In the present study, female Sprague–Dawley rats received a single oral dose of 5mg 7,12-dimethylbenz(a)anthracene (DMBA). One week later, the animals were divided into four groups: whole milk (WM), artificial whole milk (A-WM), non-fat milk (NFM) or artificial non-fat milk (A-NFM) mixed with commercial powder chow. Rats were palpated weekly to monitor tumor development. At week 20 after DMBA administration, rats were decapitated and the volume and weight of mammary tumor were recorded. Results: Tumor incidence, the cumulative number of tumors and the sums of tumor volume were higher in the WM and NFM groups than in the A-WM and A-NFM groups both at palpation and at autopsy. Conclusion: Combining our previous studies, we found the consumption of milk promoted the development of DMBA-induced mammary tumors in rats independent of the fat level. [Copyright &y& Elsevier]

Abstract: Background:: Voglibose is an α-glucosidase inhibitor used to decrease postprandial hyperglycemia in diabetic patients. Although clinical concern has not yet been raised, hepatic dysfunction has been reported in a few patients taking this drug. Method:: In the present study, we studied the effects of voglibose on the hepatotoxicity of carbon tetrachloride (CCl4) and acetaminophen (APAP) in rats, since both of these agents exert their effects through isoforms of cytochrome P450. Male Sprague–Dawley rats were given a daily ration (20g) of powdered chow diet containing 0, 2.5, 5.0 or 10.0mg/100g of voglibose. Three weeks later, the rats were challenged with either 0.50g/kg CCl4 orally or 0.75g/kg APAP intraperitoneally for biochemical examinations or killed for an in vivo metabolism study. Results:: Voglibose at these three experimental doses potentiated CCl4 and APAP hepatotoxicity, as evidenced by significantly increased levels of both plasma asparate transaminase (AST) and alanine transaminae (ALT). The glutathione (GSH) content was decreased while malondialdehyde (MDA) increased in the liver after CCl4 or APAP administration. Hepatic cytochrome P450 2E1 (CYP2E1) concentration was increased at doses of 5.0 and 10.0mg/100g of voglibose and its activity increased in the three voglibose dosage groups, while hepatic cytochrome P450 3A (CYP3A) and cytochrome P450 1A2 (CYP1A2) were only slightly changed at any dose. Conclusion:: Our study demonstrated that voglibose can potentiate CCl4 and APAP hepatotoxicity in rats by inducing hepatic CYP2E1. [Copyright &y& Elsevier]

Abstract: Objective: The prevalence of hypertension in individuals with diabetes mellitus is higher than that in individuals without diabetes mellitus. High fiber intake decreases blood glucose and lipids levels. This study investigated the effects of cereal fiber intake on systolic and diastolic blood pressures in a rat model of type 2 diabetes mellitus. Methods: Thirty male Goto Kakizaki rats were randomly assigned to one of three groups. Each group was fed a barley diet, a white rice diet, or cornstarch diet. The rats were pair fed for 16 wk. Systolic and diastolic blood pressures were measured once every 4 wk by the photoelectric oscillometric tail-cuff method without anesthesia. Results: The barley diet significantly decreased systolic blood pressure from week 12 and decreased the plasma levels of total cholesterol, triacylglycerol, and low-density lipoprotein cholesterol. There were significant positive correlations between plasma lipids levels and systolic blood pressure. Conclusions: High fiber intake has beneficial effects on systolic blood pressure and blood lipids levels and suggests that fiber intake should be increased in individuals who have diabetes mellitus to prevent complications. [Copyright &y& Elsevier]

To examine whether the considerable quantities of increased female sex hormone levels found in modern milk as a result of modern dairy farming practices are safe for human consumption.Males and females of the P generation were maintained on a diet containing milk for 10 weeks before mating. Exposure to milk was continued up to the end of weaning of the F2b offspring.Two-generation reproduction study.Male and female Wistar Galas rats.P- and F1-generation rats were mated.Fertility, fecundity, and morphology and function of reproductive organs.Although milk had growth-promoting effects in both parents and offspring, it caused no impairments in fertility, fecundity, or reproductive organ development in either generation. However, a whole litter from a dam of the P generation was born dead, three litters in total had a pup with skeletal abnormalities, and the AGD of F2a female pups was reduced. These events occurred only in the milk-treated rats. It is unknown whether these issues had any relevance to milk or only happened by chance.Further study is required to determine whether milk from pregnant cows is completely free from adverse effects on reproductive health. [Copyright &y& Elsevier]

After the successful test at the Takasago factory of Kobe Steel Ltd (KSL). 920 MHz magnet was transported and installed in Tsukuba Magnet Laboratory (TML), NIMS in April, 2002. To achieve a quick energization and long term operation with a minimum number of operators, the cryostat was equipped with an automated control and monitoring system. During the cooling process below 4.2 K and the energization procedure up to 21.6 T, the temperature of the magnet and He II bath was controlled automatically. Since the all installation procedure has completed in July 2002, the magnet has been continuously cooled to 1.545 K and the temperature variation has been kept within 0.01 K for over a year. [ABSTRACT FROM AUTHOR]

The first 920 MHz high-resolution NMR (Nuclear Magnetic Resonance) magnet was successfully installed at the Tsukuba Magnet Laboratory of the National Institute for Materials Science. A persistent operation at 21.6 T has continued since April 2002 without any problems. Excellent field stability of 0.31 Hz/h was observed from December 2002 to January 2003. Since July 2002, the magnet was used as an essential part of the only 920 MHz high-resolution NMR spectrometer in the world. The signal-to-noise ratio of 0.1 % ethylbenzene using a proton-selective probe was as high as 2981. An HCN triple-resonance probe is now attached to the spectrometer to contribute to the National Project on Protein Structural and Functional Analysis in Japan. The completion of the second 920 MHz-class NMR spectrometer is scheduled for spring 2004. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of high carbohydrate/low fat diet on glucose tolerance and on lipid profiles, we performed a 4-week crossover study. Japanese subjects (30 patients with type 2 diabetes mellitus, 15 subjects with impaired glucose tolerance and 8 subjects with normal glucose tolerance) were allocated either 55% standard carbohydrate/30% fat (sc) or 70% high carbohydrate/15% low fat (hc) diet for four weeks, and evaluated by OGTT and various parameters. Then, the diet was crossed over to another diet, and identical parameters were re-evaluated after four weeks. Area under the glucose concentration-time curve (AUG) or triglyceride did not show significant changes between the two diets. HDL–Cholesterol and body mass index decreased significantly by hc diet. Free fatty acids and homeostasis model assessment insulin resistance index showed a tendency to be decreased by hc diet. AUG hc/sc ratio was inversely correlated with AUG or free fatty acids on standard carbohydrate diet. In conclusion, the present 4-week high carbohydrate/low fat diet may be useful to reduce body weight and insulin resistance. The 4-week high carbohydrate/low fat diet did not affect glucose tolerance as a whole. Although the 4-week high carbohydrate/low fat diet decreased HDL–Chol, it did not increase triglyceride. [Copyright &y& Elsevier]

Prostate cancer has become the most common cancer among men in tire United States. Although milk consumption is considered to be a risk factor in some epidemiotogical studies, the results are inconsistent. A meta-analysis method was conducted to estimate the combined odds ratio (OR) between milk consumption and prostate cancer.from case-control studies published between 1984 and 2003 using commercial software (comprehensive meta-analysis). The combined OR was 1.68(95% confutence interval = 1.34–2.12) in the 11 published case-control studies. The combined OR vatted little by study stratification. Additionally, we evaluated the possible risk factors in milk for prostate cancer. In conclusion, we found a positive association between milk consumption and prostate cancer. The underlying mechanisms, including fat, calcium, hormones, and other factors, should be investigated further. [ABSTRACT FROM AUTHOR]

Troglitazone (TRZ) is the first of a new group of oral antidiabetic drugs, the thiazolidinediones, and is proven to lower plasma glucose levels in patients with type 2 diabetes mellitus. However, the concern has been raised because of several reports, in which severe hepatic dysfunction leading to hepatic failure was demonstrated in a few patients receiving the drug. We studied the effects of TRZ on the hepatotoxicity of carbon tetrachloride (CCl4) and acetaminophen (APAP) in rats, both of which exert their toxic effects through bioactivation associated with cytochrome P450 3A (CYP3A) and 2E1 (CYP2E1).Male standard (Wistar/ST) and type 2 diabetic model (GK/Jal) rats were kept on a powdered chow diet containing 0, 100, 500 mg/kg/rat of TRZ. Three weeks later, the rats were either sacrificed for an in vitro metabolism study or challenged with 0.50 g/kg CCl4 p.o. or 0.75 g/kg APAP i.p.TRZ at 100 and 500 mg/kg/rat increased the CYP3A level as well as the testosterone 6β-hydroxylation activities in liver microsomes, but did not affect CYP2E1. TRZ also enhanced APAP hepatotoxicity, as evidenced by significantly increased levels of alanine aminotransferase, aspartate aminotransferase and α-glutathione S-transferase in the plasma of rats, and by significantly low hepatic glutathione concentration.Our study demonstrated that high doses of TRZ can enhance hepatotoxicity of APAP in Wistar/ST and GK/Jal by inducing hepatic CYP3A. [Copyright &y& Elsevier]

We studied magnetizations of over-doped Bi2Sr2CaCu2O8+y single crystals. The thermoremanent magnetization shows an anomalous random oscillation in low frequency modulation field below 20 K. The result indicates a random motion of the vortices, which suggest there exists a new magnetic phase in the vortex solid phase. [Copyright &y& Elsevier]

Questions the necessity of a high carbohydrate intake before the administering of oral glucose-tolerance tests (OGTT). Study by Wilkerson et al; Findings.