Biomedical subjects

Y Fukui

Publications and source records attributed to Y Fukui.

At least 19 recordsLinked to original sources

PubMed2006

Development of cerebral sulci and gyri in fetuses of cynomolgus monkeys (Macaca fascicularis).

This study aimed to clarify the development of sulci and gyri on the external surface of the cerebrum of cynomolgus monkeys. Sulcus formation began with the appearance of the lateral fissure on embryonic day (ED) 70, followed by delineations of four cerebral lobes by the emergence of the parietooccipital sulcus, central sulcus, and preoccipital notch on EDs 80-90. The following primary sulci were then visible until ED 120: the superior temporal sulcus on ED 90; the intraparietal sulcus, lunate sulcus, inferior occipital sulcus, and arcuate sulcus on ED 100; and the principle sulcus on ED 110; the occipitotemporal sulcus, anterior middle temporal sulcus, and superior postcentral dimple on ED 120. These sulci demarcated the superior temporal gyrus on ED 90, the precentral gyrus, supramarginal gyrus, and angular gyrus on ED 100, and the inferior and middle temporal gyri, postocentral gyrus, superior parietal lobule, superior, middle and inferior frontal gyri, and inferior occipital gyrus on ED 120. Except for the intermediate and lateral orbitofrontal sulci, the sulci that appeared on ED 130 and thereafter were not related to the gyrus demarcations. Intriguingly, the brain markedly gained weight on EDs 100 and 120, corresponding to the embryonic ages when almost all gyri were visible. The results suggest that a rapid growth of the cerebrum involves convolutions of the gyri by a regular sequence of the sulcus formation in cynomolgus monkeys. This study further provides a standard of reference for normal development in the cerebral cortical morphology of cynomolgus monkeys.

Animals↗

PubMed2006

Dissolution behavior and in vitro evaluation of sputtered hydroxyapatite films subject to a low temperature hydrothermal treatment.

Hydroxyapatite (HA) was coated onto titanium substrates using radio frequency sputtering. Some of the as-sputtered films were hydrothermally recrystallized at 110 degrees C. In immersion tests, the as-sputtered film completely dissolved after 2 days in a culture medium, whereas the thickness of hydrothermally treated films increased with an increase in immersion period, reaching a thickness of 127% after a period of 4 weeks. The proliferation and alkaline phosphatase (ALP) activity of MC3T3-E1 osteoblast-like cells on the as-sputtered and hydrothermally treated films were investigated, and the cell morphology was also observed using scanning electron microscopy. The proliferation of MC3T3-E1 cells on the as-sputtered films was suppressed, whereas proliferation on the hydrothermally treated films was comparable to that on control and titanium substrate. The suppression of cell proliferation is associated with an increase in pH of the culture medium caused by dissolution of the as-sputtered film. After a 96-h culture time, the ALP activity of the cells on the hydrothermally treated film was higher than that on the control, titanium substrate, and as-sputtered film samples. From scanning electron microscopic observations, it was found that the MC3T3-E1 cells on the hydrothermally treated films were elongated and had established more intricate filopodia networks with each other, which were also observed for MC3T3-E1 cells on the as-sputtered films after a period of 24 h.

Animals↗

PubMed2006

Genetic polymorphisms at FCER1B and PAI-1 and asthma susceptibility.

BACKGROUND: We previously detected a promoter polymorphism (- 109C/T) in the gene for the beta-chain of the high-affinity receptor for IgE (FCER1B), which was associated with total serum IgE levels but not with asthma in a Japanese population. A genetic interaction is biologically plausible between FcepsilonRI-beta and the plasminogen activator inhibitor 1 (PAI-1), which is highly expressed in mast cells in asthmatics and plays an essential role in airway remodelling. We hypothesized that FCER1B promoter polymorphisms, by modifying the intensity of mast cell activation signals, modulate the genetic effects of a functional 4G/5G polymorphism in the PAI-1 gene on asthma. OBJECTICIVE: To examine whether FCER1B promoter polymorphisms (- 109C/T and - 654C/T) influence the genetic effects of the functional polymorphism (4G/5G) at the PAI-1 promoter region on asthma susceptibility using a case-control analysis. METHODS: Subjects (374 asthmatic patients and 374 non-asthmatic controls) were divided into combined genotype groups based on the presence of FCER1B - 109TT and - 654CC genotypes and the PAI-1 4G allele. Logistic regression analysis was used to estimate adjusted odds ratios for asthma associated with the different genotype groups. RESULTS: Individuals homozygous for the FCER1B - 109T/ - 654C haplotype and the PAI - 1 5G allele had a reduced susceptibility to asthma; the odds ratio for the development of asthma was 0.20 (95% confidence interval, 0.084 - 0.46; P = 0.00015) for them, compared with individuals also homozygous for the - 109T/- 654C haplotype at FCER1B but carrying the 4G allele at PAI-1. The regression model also showed an interaction of the PAI-1 4G/5G genotype with the FCER1B-109C/T (P for interaction = 0.0017) or FCER1B-654C/T (P for interaction = 0.031) on asthma. CONCLUSION: The present findings suggest a synergistic interaction between FCER1B and PAI-1 genes in asthma susceptibility.

Adolescent↗

PubMed2006

Sequence variants of the secreted phosphoprotein 1 gene are associated with total serum immunoglobulin E levels in a Japanese population.

BACKGROUND: Secreted phosphoprotein 1 (SPP1) is a cytokine with pleiotrophic immunological activities, including activation of macrophage chemotaxis and T-helper type 1 (Th1) immune responses. SPP1 gene polymorphisms have been shown to be associated with several immune inflammatory diseases including multiple sclerosis (MS), which is characterized by fewer allergic symptoms and lower numbers of allergen sensitizations. OBJECTIVE: The present study examined whether SPP1 gene polymorphisms are associated with total serum IgE levels, atopy and asthma in a Japanese population. METHODS: This case-control association analysis examined 611 subjects, including 268 subjects with asthma. We genotyped three promoter and two exon polymorphisms at SPP1: -1687A/G; -381T/C; -94 deletion/G; 5891C/T; and 7052T/C. Results Association analyses of SPP1 polymorphisms showed that homozygosities for the 5891T allele (P=0.009) and 7052C allele (P=0.001) were significantly associated with increased levels of total IgE in non-asthmatic subjects. However, these variants were not associated with asthma and atopy. Interestingly, individuals carrying the 5891C allele, which is more prevalent in patients with MS in Japanese populations, displayed significantly lower levels of total serum IgE. Individuals homozygous for the 7052C allele, which is associated with development of systemic lupus erythematosus, displayed significantly higher total serum IgE levels. CONCLUSION: These findings suggest that genetic polymorphisms in SPP1 may play a role in controlling basal levels of total serum IgE, independent of atopy.

Adult↗

PubMed2006

Corticotropin-releasing factor immunoreactivity increases in the cerebellar climbing fibers in the novel ataxic mutant mouse, pogo.

The ataxic pogo mouse (pogo/pogo) is a novel neurological mutant, which was derived as an inbred strain (KJR/MsKist) from a Korean wild mouse. The pathological manifestations include a difficulty in maintaining a normal posture, the failure of inter-limb coordination and an inability to walk straight. In this study, we examined the distribution of corticotropin-releasing factor (CRF) immunoreactive cerebellar climbing fibres and their projections to tyrosine hydroxylase (TH) immunoreactive Purkinje cells in the cerebellum of the pogo mutant mouse using immunohistochemistry. In the pogo/pogo mouse, a subset of climbing fibres was stained more intensely for CRF than in the control. Moreover, ataxic pogo mouse, neurons of the inferior olivary nucleus projecting climbing fibres were also more intensely stained for CRF than in the control. In the pogo/pogo mouse, TH immunoreactivity was located in the Purkinje cells, whereas no TH expression was found in the control. Double immunostaining for CRF and TH in the pogo/pogo cerebellum revealed that the distribution of TH-immunoreactive Purkinje cells corresponded to terminal fields of CRF-immunoreactive climbing fibres but not to the CRF-immunoreactive mossy fibres. Therefore, we suggest that an increase of CRF level may alter the function of targeted Purkinje cells and that it is related to the ataxic phenotype in the pogo mutant mouse.

Animals↗

PubMed2006

The absence of phosphorylated tyrosine hydroxylase expression in the purkinje cells of the ataxic mutant pogo mouse.

The pogo mouse is a new ataxic autosomal recessive mutant that arose in Korean wild mice (KJR/Mskist). Its ataxic phenotype includes difficulty in maintaining a normal posture and the inability to walk in a straight line. Several studies have reported that tyrosine hydroxylase (TH) is persistently ectopically expressed in particular subsets of Purkinje cells in a parasagittal banding pattern in several ataxic mutant mice, e.g. tottering alleles and pogo mice. In this present study, we examined the expression of an enzymatically active form of TH and phosphorylated TH at Ser(40) (phospho-TH) by using immunohistochemistry and double immunofluorescence in the cerebellum of pogo mice. TH immunostaining appeared in some Purkinje cells in pogo, but in only a few of Purkinje cells of their heterozygous littermate controls. In all groups of mice, no phospho-TH immunoreactive Purkinje cells were observed in the cerebellum, although subsets of TH immunoreactive Purkinje cells were found in adjacent sections. This study suggests that TH expression in the Purkinje cells of pogo abnormally increases without activation of this enzyme by phosphorylation. This may mean that TH in the Purkinje cells of these mutants does not catalyse the conversion of tyrosine to l-DOPA, and is not related to catecholamine synthesis.

Animals↗

PubMed2006

Increased serotonergic innervation of lumbosacral motoneurons of rolling mouse Nagoya in correlation with abnormal hindlimb extension.

Rolling Mouse Nagoya (RMN) carries a mutation in a gene encoding for alpha(1A) subunit of P/Q-type Ca(2+) channel (Ca(v)2.1). In addition to ataxia, this mutant mouse exhibits abnormal hindlimb extension, which is characterized by a sustained excessive tone of hindlimb extensor muscles. This study aimed to clarify whether serotonergic (5-HTergic) innervation of the spinal motoneurons was altered in RMN in relation to the abnormal hindlimb extension. The density of 5-HT immunoreactive fibres in the ventral horn of lumbar and sacral regions of spinal cord was significantly greater in RMN than in controls. Retrograde wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) labelling combined with 5-HT immunostaining revealed that the number of 5-HT immunoreactive terminals adjoining femoris quadriceps motoneurons was about 2.5-fold greater in RMN than in controls. Furthermore, 5-HT immunostaining in the lumbar cord ventral horn was examined in three other Ca(v)2.1 mutant mice (tottering, leaner and pogo) as to whether or not they showed the abnormal hindlimb extension. Among these mutants, the increased density of 5-HT immunoreactive fibres was observed in correlation with the presence of the abnormal hindlimb extension. The results suggest an increased 5-HTergic innervation of the lumbosacral motoneurons in correlation with the abnormal hindlimb extension in RMN and other Ca(v)2.1 mutant mice. As 5-HT is known to induce the sustained membrane depolarizations without continuous excitatory synaptic inputs (plateau potentials) in spinal motoneurons, the increased 5-HTergic innervation may cause the sustained excitation of hindlimb extensor motoneurons, resulting in the abnormal hindlimb extension.

Animals↗

PubMed2006

Simple conjugation and outgrowth procedures for tagging vibrios with GFP, and factors affecting the stable expression of the gfp tag.

AIM: Our goal was to develop a simple system for tagging wild-type marine bacteria with gfp. METHODS AND RESULTS: Escherichia coli strain CC118lambdapir carrying the conjugative helper plasmid pEVS104 and the gfp-containing plasmid pKV111 was used to transfer gfp to Vibrio recipients. Four different media were tested for their ability to support the growth of recipients, but not the E. coli donor, to allow powerful enrichment of gfp-tagged wild-type vibrios from mating mixes. Forty-three vibrio strains, representing 39 different species, were successfully tagged with gfp using the conjugative transfer from E. coli followed by selective outgrowth at 15 degrees C on ZoBell 2216E agar containing 0.5% sodium alginate. Using this outgrowth medium, colonies of GFP-expressing vibrio clones were detectable within 4 days. The percentage of visibly fluorescent cells in three representative GFP-tagged vibrios was higher at 15 degrees C than at 20 or 25 degrees C (c. 50% vs. 45% or 40%, respectively), and was also higher during the aerobic rather than the anaerobic culturing (c. 50% vs. 35%, respectively). CONCLUSIONS: We found a simple selective outgrowth technique that enabled us to isolate a wide variety of GFP-tagged marine vibrios following the conjugative transfer of gfp from E. coli. SIGNIFICANCE AND IMPACT OF THE STUDY: Tagging cells with GFP and related fluorescent proteins is a powerful approach for investigating the bacteria in situ, particularly during the colonization of hosts. The simple and cost-effective outgrowth condition described in this study could be applied to construct a wide variety gfp-tagged marine bacteria.

Conjugation, Genetic↗

PubMed2006

No meaningful increase in urinary tubular dysfunction markers in a population with 3 microg cadmium/g creatinine in urine.

The critical Cd exposure level to induce tubular dysfunctions is a focus of public concern among general populations in Japan. To answer this question, one group each (about 1000 adult women/area) in nonpolluted areas with high (Area H) and low Cd exposure (Area L) was obtained, and 742 strictly age-matched pairs of never-smoking adult women were selected for comparison. Cd, alpha1-MG (microglobulin) and beta2- MG in urine were taken as markers of exposure and tubular dysfunction, respectively. Geometric mean Cd levels as corrected for creatinine (Cdcr) was greater than three times higher in Area H (2.8 microg/g cr) than in Area L (0.8 microg/g cr). Nevertheless, beta2-MGcr did not differ between the two areas (125 microg/g cr for Area H vs 118 microg/g cr for Area L). alpha1-MGcr was only marginally higher in Area H (2.8 mg/g cr) than in Area L (2.1 mg/g cr), with no biomedical significance. Results were essentially the same when analyses were conducted with noncorrected observed values or values corrected for a specific gravity. Thus, the effects of Cd exposure in Area H on renal tubular function should be essentially nil.

Adult↗

PubMed2006

Preparation of germanium apatite and its cytotoxicity.

Germanium apatite was synthesized via the solid-state reaction between GeO(2) and (NH(4))(3)PO(4). The synthesized materials were characterized using XRD, and thermal analysis was carried out using TG-DTA. Ge(2)P(2)O(7) was preferentially produced at temperatures between 300-900 degrees C, and at temperatures above 1000 degrees C, germanium apatite (Ge(5)O(PO(4))(6), GeAp) was synthesized. In solubility tests, 0.36% and 0.65% of Ge ions were liberated from GeAp powder in distilled water at 37 and 80 degrees C after four weeks, respectively. A GeAp aqueous solution maintained at 37 degrees C was strongly acidic with a pH=1.67 after four weeks. The growth rate of human adult gingival fibroblast cells in a medium that included GeAp, HA, and GeO(2) was investigated. The growth rate of the cells in a 0.1 mg/ml GeAp medium was almost the same as that in the control. The cell growth was restricted in a 1.0 mg/ml GeAp medium, whereas the cell growth in a pH-adjusted 1.0 mg/ml GeAp medium at pH=7.60 was higher than that in non-adjusted medium at pH = 7.06.

Apatites↗

PubMed2006

Effect of a thin HA coating on the stress/strain distribution in bone around dental implants using three-dimensional finite element analysis.

Three-dimensional finite element analysis was performed for thin hydroxyapatite (HA) coated and titanium dental implants to study the effects on stress/strain distribution in the mandible with application of axial and oblique loads. The implants were of screw and cylinder types. With an axial load, the maximum equivalent bone stresses in the titanium implants were 21.5 and 29.0 MPa for the cylinder and screw types respectively, and the stress and strain distributions differed. For the cylinder type, the highest stress was located at the implant base, and for the screw type, it was located at the top edge of the first thread within the cortical bone. For the HA-coated cylinder and screw implants, the maximum equivalent bone stresses were 7.1 and 7.2 MPa respectively. The stress and strain distributions were similar, and the highest stress was located on the upper side of the cortical bone around the implant neck for both implants. Of the implants examined, the screw type HA-coated implant had the most uniform stress distribution in bone.

Anisotropy↗

PubMed2006

Bone response to titanium implants coated with thin sputtered HA film subject to hydrothermal treatment and implanted in the canine mandible.

Hydroxyapatite (HA) was coated onto titanium implants using radio frequency magnetron sputtering. The HA films were crystallized in an autoclave tube using low temperature hydrothermal treatment. The average film thickness on the implant was 1.1 microm. HA-coated and pure-titanium implants were inserted into canine mandibles for up to 24 weeks. Forty-eight implants were placed in eight beagles. After 2, 4, 12 and 24 weeks, implants were retrieved and prepared for histological observation, and the HA film thickness was determined using energy-dispersive X-ray spectroscopy. Light microscopy revealed that, after two weeks, the bone response to the HA-coated implants was much better than to the pure titanium implants, and osteoblasts were observed at the bone-implant interface. After four weeks, the screw threads of the HA-coated implants were almost completely covered with bone. The HA film thickness rapidly decreased up to four weeks of implantation, then gently decreased, reaching 0.40+/-0.03 microm at the upper region of the implant after 12 weeks. That indicates that about 80% of the HA film had dissolved after 12 weeks of implantation. The rate of decrease in the HA film thickness was greater with increasing implant depth.

Animals↗

PubMed2005

Low-level cadmium exposure in Toyama City and its surroundings in Toyama prefecture, Japan, with references to possible contribution of shellfish intake to increase urinary cadmium levels.

OBJECTIVES: This study was initiated to examine if exposure to cadmium (Cd) was high also outside of the previously identified Itai-itai disease endemic region in the Jinzu River basin in Toyama prefecture in Japan. METHODS: Morning spot urine samples were collected in June-August 2004 from 651 adult women (including 535 never-smokers) in various regions in Toyama prefecture, and subjected to urinalyses for cadmium (Cd), alpha1-microglobulin (alpha1-MG), beta2-microglobulin (beta2-MG), N-acetyl-beta-D-glucosaminidase (NAG), specific gravity (SG or sg) and creatinine (CR or cr). Three months later, the second urine samples were collected from those with elevated Cd in urine (e.g., > or =4 microg/g cr), together with answers to questionnaires on shellfish consumption. RESULTS: The geometric mean (GM) Cd, alpha1-MG, beta2-MG and NAG (after correction for CR) for the total participants were 2.0 microg/g cr, 2.4 mg/g cr, 104 microg/g cr and 2.8 units/g cr, respectively; further analysis with never-smoking cases only did not induce significant changes in these parameters. Analyses of the second urine samples from the high Cd subjects showed that there was substantial decrease (to about a half) in Cd in the 3-month period, and that the decrease was accompanied by reduction in alpha1-MG and NAG (beta2-MG did not show elevation even in the first samples). The urinalysis results in combination with the results of the questionnaire survey suggest that the high urinary Cd was temporary and might be induced by intake of shellfish that is edible whole. CONCLUSIONS: The overall findings appear to suggest that Cd exposure in Toyama populations (outside of the Itai-itai disease endemic region) was at the levels commonly observed on the coast of the Sea of Japan, and that the Cd level in urine might be modified by the intake of some types of seafood. Further studies are necessary to elucidate the relation of urinary Cd with seafood intake.

Acetylglucosaminidase↗

PubMed2005

Smoking-induced increase in urinary cadmium levels among Japanese women.

OBJECTIVE: To examine if cigarette smoking will induce elevation in cadmium (Cd) in urine. METHODS: Information on smoking habits, and urinary levels of cadmium (Cd-U), alpha(1)-microglobulin (alpha(1)-MG), beta(2)-microglobulin (beta(2)-MG), creatinine (CR or cr), and urine specific gravity (SG or sg) was cited from a combination of three previously established databases on adult Japanese women. After exclusion of those with unclear answers on smoking habits (412 cases), the combination (12,846 cases) gave 11,092, 1420 and 334 cases of never, current and former smokers, respectively, for present statistical analyses. RESULTS: Multiple regression analyses taking Cd-U as a dependent variable and 11 regions of urine collection, age and smoking habits as independent variables showed that age and regions were powerful confounders in the analysis for the effects of smoking on Cd-U. To exclude the confounding effects, current and former smokers were paired with age- and region-matched never smoking controls in subsequent analyses. In addition, former smokers were paired with age- and region-matched current smokers. The comparison of the paired cases showed that Cd-U for current smokers was significantly higher than that for never smokers. The levels for former smokers were however not higher than the levels for never smokers. When classified by the number of cigarettes consumed per day, Cd-U for current smokers increased dependently to the number of cigarettes (about 0.09 microg/cigarette/day) with leveling off at 15 or more cigarettes. There was a subtle cigarette dose-dependent increase in alpha(1)-MG, but the increase was insignificant in case of beta(2)-MG. Estimation of the amount of Cd absorbed due to cigarette smoking followed by comparison with the increase in Cd-U suggested that almost all Cd absorbed will be excreted into urine. CONCLUSIONS: Among currently smoking Japanese women, cadmium in urine increased in a manner dependent to the number of cigarettes consumed daily. Thus, smoking is a confounder of Cd-U evaluation even among the population with relatively high dietary Cd burden.

Adult↗

PubMed2005

Decreases in urine specific gravity and urinary creatinine in elderly women.

OBJECTIVE: To examine the effects of aging on urinary levels of creatinine (CR) and urine specific gravity (SG) among women in a large-scale epidemiology survey. METHODS: Data on CR and SG in urine, together with smoking habits and menopausal status, were selected from previously established databases and combined with the results of supplemental sample collection. In total, CR and SG data were available for 11,090 never-smoking women (total group; 29-80 years of age); a subgroup of 1,851 women who lived in Kyoto was also selected from the total group. Data from the two groups were subjected to statistical analyses. In statistical evaluation, SG was converted to factor G, which was defined as (SG-1.000)x1,000. RESULTS: Classification by decade of years of age showed that both CR and SG decreased steadily as a function of advancement in age over 30 years, both in the total group and in the Kyoto subgroup, showing high reproducibility of the observation on a whole-country basis and on a local basis. When the levels at 80 years of age were compared with those at 30 years, there was an approximately 60% and 30% decrease in CR and factor G, respectively. Thus, the effects of aging were more marked on CR than on factor G (and therefore on SG). Menopause appeared to be an influential factor in the reduction of CR and SG, separately from aging itself. CONCLUSIONS: Urinary levels of creatinine and, to a lesser extent, urine specific gravity, steadily decreased as a function of ages of over 30 years in women.

Adult↗

PubMed2005

Effects of aging on cadmium and tubular dysfunction markers in urine from adult women in non-polluted areas.

OBJECTIVES: The objectives of the present analyses were to examine if Cd and tubular dysfunction marker levels in urine show age-dependent changes among women who lived in areas with no known cadmium (Cd) pollution in Japan, and if the trends would be further modified by correction of analyte concentration in terms of urinary creatinine (CR or cr) or urine specific gravity (SG or sg). METHODS: The results of urinalysis for Cd, alpha(1)-microglobulin (alpha(1)-MG), beta(2)-microglobulin (beta(2)-MG), and N-acetyl-beta-D: -glucosaminidase (NAG) concentrations together with CR and SG were cited from previously established databases. A majority of urine samples were collected in 2000-2002 from adult women (mostly at 40-60 years of age) in various areas in Japan, and the collection was supplemented by cases of > or =60-year-old women in 2003. In total, 11,090 never-smoking cases were subjected to statistical analysis. The values as observed (e.g., Cd(ob)), together with after correction for CR (e.g., Cd(cr)) or SG (e.g., Cd(sg)), were examined by linear regression analysis after logarithmic conversion. RESULTS: The geometric mean (GM) values for Cd were 1.10 microg/l (as observed) or 1.32 microg/g cr (after correction for creatinine concentration). No increases were found in the levels of alpha(1)-MG, beta(2)-MG or NAG on a group basis, in agreement with the conditions that there was no known environmental pollution with Cd in the sampling areas. There were almost linear increases in logarithm of Cd, alpha(1)-MG, beta(2)-MG and NAG concentrations as age advanced. As CR, and to a lesser extent SG, also decreases steadily throughout life, the correction of the analyte concentrations for urine density induced substantial increases in the analyte values; i.e., the correction by CR and SG induced amplification of the increases by two- and 1.4-times, respectively, compared with the increase in non-corrected observed values. CONCLUSIONS: There were age-related increases in Cd and tubular dysfunction markers in urine among women in areas with no known Cd pollution. The increase was amplified two- or 1.4-times when CR or SG correction was applied, respectively. The observation suggests that care should be practiced in applying CR or SG correction, especially when evaluation of Cd exposure and resulting health effects is made among elderly populations.

Aging↗

PubMed2005

Reproducibility of urinary cadmium, alpha1-microglobulin, and beta2-microglobulin levels in health screening of the general population.

The present study examined whether levels of cadmium, and alphal- and beta2-microglobulin in urine (Cd-U, ac-MG-U, and beta2-MG-U, respectively) were reproducible in urine samples collected from the same subjects on multiple occasions. For this purpose, two databases on background exposure to cadmium in Japan-one from study I between 2000 and 2001 and the other from study II in 2002-were revisited to find 231 apparently healthy, nonpregnant, nonlactating adult women who participated in both studies and thus had provided two urine samples. The databases contained information on Cd-U, alphal,-MG-U, and beta2-MG-U, creatinine (CR), and specific gravity (SG) as well as smoking and other lifestyle factors. Of the 231 women, 195 who had never smoked were selected for the present analysis. Cd-U as well as alpha1-MG-U were reproducible (e.g., with correlation coefficients [r] between study I and II results of 0.4 to 0.6) when measured on two occasions 9 to 10 months apart. The r values were lower for beta2-MG-U (r0.3). Exclusion of urine samples with inadequate urine density(i.e., CR <0.5 or >3.0 g/L or SG <1.010 or >1.030) resulted in substantial improvement of the agreements between the two measures (e.g., r = 0.6 to 0.7 for Cd-U and alpha1-MG-U). CR and SG correlated closely with each other, especially in low-density urine samples (r >0.9), and therefore the effects of CR and SG could not be evaluated separately. In the overall evaluation,single determination (i.e., without repeated urine sampling) of Cd-U and alpha1-MG-U should be acceptable, and it may also be acceptable for beta2-MG-U. Use of samples with adequate urine density rather than application of density correction to low-density urine samples in recommended.

Cadmium↗

PubMed2005

Post-natal changes of cyclin-dependent kinase 5 activator expression in the developing rat cerebellum.

cDNA of cyclin-dependent kinase 5 (Cdk5) was cloned based on its primary sequence homology to Cdc2 and Cdk2. Cdk5 requires the neuronal Cdk5 activators such as p35 or p39(nck5ai) (p39) for its activity. In this study, we examined post-natal changes in the p39 expression pattern during the development of the rat cerebellum. p39 began to express in somata and dendrites of Purkinje cells at post-natal day 3 (PD3). In particular, at PD12, parasagittal bands (stripes) with p39 immunoreactivity were weakly observed. At PD21, p39-immunoreactive stripes were developed when compared with the PD12 group. At this age stage, p39 immunoreactivity became weak in somata of Purkinje cells, not forming stripes. At PD28, a series of parasagittal bands were more distinct than those of the PD21 group, and p39 immunoreactivity disappeared in Purkinje cells, not forming p39 immunoreactive stripes. In the adults, p39 immunoreactivity in Purkinje cells was similar to that found in the PD28 group which showed that parasagittal bands were very narrow, and became progressively more slender. Therefore, we suggest that the post-natal changes of p39 expression in Purkinje cells in the cerebellum is an autonomous characteristic of Purkinje cells with a role of Cdk5 activators.

Animals↗