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N Kawakami

Publications and source records attributed to N Kawakami.

At least 19 recordsLinked to original sources
PubMed2001

Correlation between the age of pinealectomy and the development of scoliosis in chickens.

STUDY DESIGN: Pinealectomy induces experimental scoliosis in chickens. This study analyzed the correlation between the age at which pinealectomy was performed and the development of scoliosis in chickens. OBJECTIVE: To investigate the differences in the rate or magnitude of scoliosis and the type of curvature in chickens pinealectomized at different times after hatching. SUMMARY OF BACKGROUND DATA: Scoliosis develops in almost all chickens pinealectomized within 3 days after hatching, but there are no data on whether the condition will develop in chickens pinealectomized earlier or later after hatching. METHODS: In this study, 106 female white leghorn chickens were divided into six groups: four pinealectomy groups (pinealectomy was performed 2, 4, 11, or 18 days after hatching in Groups P-2, P-4, P-11, and P-18, respectively), a control group (Group C), and a sham operation group (Group S). Ventrodorsal radiographs of the spine were taken at 4-week intervals until the age of 12 weeks. At 12 weeks, a 1-mL sample of blood was taken from the heart at the middle of the dark cycle, and the serum melatonin concentration was measured by radioimmunoassay. RESULTS: At the age of 12 weeks, scoliosis was present in 63.6% of the chickens in Group P-2, 72.7% in Group P-4, 81% in Group P-11, and 70% in Group P-18, and the Cobb angles in the scoliotic chickens averaged 32.6, 29.8, 23.8, and 22.3 degrees in the respective groups. There were no significant differences in the rate or magnitude of scoliosis and the type of curvature among the pinealectomy groups at the age of 12 weeks. At the age of 12 weeks, the serum melatonin levels at the middle of the dark cycle in the pinealectomized chickens were significantly lower than those of chickens in Groups C and S. However, there were no differences in the serum melatonin levels between scoliotic and nonscoliotic pinealectomized chickens. CONCLUSIONS: Findings from this study show that scoliosis develops in 60% to 80% of chickens pinealectomized within 18 days after hatching, and that scoliotic development is not influenced by the age at which pinealectomy is performed. However, this study suggests that melatonin plays a complicated role in spinal development, inasmuch as the serum melatonin levels after pinealectomy approximated zero. Yet scoliosis did not develop in all pinealectomized chickens.

Aging↗
PubMed2001

Soy product intake and hot flashes in Japanese women: results from a community-based prospective study.

The association between soy product intake and the occurrence of hot flashes was examined in a cohort of 1,106 female residents of Takayama, Gifu, JAPAN: The women were aged 35-54 years and premenopausal at their entry into the study in 1992. Diet, including intake of soy products and isoflavones, was assessed by means of a validated semiquantitative food frequency questionnaire at study entry. A follow-up mail questionnaire asking about experiences of hot flashes was sent in 1998. During the 6 years of the study period, 101 women had new moderate or severe hot flashes according to the Kupperman test of menopausal distress. After data were controlled for age, total energy intake, and menopausal status, hot flashes were significantly inversely associated with consumption of soy products in terms of both total amount (highest tertile of soy product intake (g/day) vs. lowest: hazard ratio = 0.47; 95% confidence interval: 0.28, 0.79; p for trend = 0.005) and isoflavone intake (highest tertile of isoflavone intake (mg/day) vs. lowest: hazard ratio = 0.42; 95% confidence interval: 0.25, 0.72; p for trend = 0.002). These data suggest that consumption of soy products has a protective effect against hot flashes.

Adult↗
PubMed2001

Analysis of cartilage-derived retinoic acid-sensitive protein in cerebrospinal fluid From patients With spinal diseases.

STUDY DESIGN: The expression of cartilage-derived retinoic acid-sensitive protein (CD-RAP) was measured in cerebrospinal fluid from patients with spinal diseases. OBJECTIVES: To quantify the levels of CD-RAP in human cerebrospinal fluid and to clarify its character. SUMMARY OF BACKGROUND DATA: Cartilage-derived retinoic acid-sensitive protein is a newly discovered, secreted molecule that is expressed during the chondrogenesis phase of endochondral bone formation and in articular cartilage. In recent studies CD-RAP has been detected in the serum of patients with melanoma and breast cancer, and it has been used to monitor tumor activity. However, the function of CD-RAP is unknown, and the expression of CD-RAP in human cerebrospinal fluid has never been reported. METHODS: The concentration of CD-RAP in human cerebrospinal fluid was measured by enzyme-linked immunosorbent assay with antihuman CD-RAP antibodies. Cerebrospinal fluid samples were collected from two groups of patients. Group 1, the control group, consisted of 40 patients: 22 with trauma and 18 with gynecologic diseases. Group 2 consisted of 172 patients with spinal diseases: 5 with meningioma, 5 with neurinoma, 5 with arachnoid cyst, 30 with cervical spondylotic myelopathy, 35 with lumbar disc herniation, 56 with lumbar canal stenosis, and 36 with scoliosis. RESULTS: The concentration of CD-RAP in the control group was 16.5 +/- 8.3 ng/mL. The concentrations of CD-RAP in Group 2 were: 35.3 +/- 14.7 ng/mL in meningioma, 23.5 +/- 7.41 ng/mL in neurinoma, 26.0 +/- 22.2 ng/mL in arachnoid cyst, 41.7 +/- 22.3 ng/mL in cervical myelopathy, 27.8 +/- 14.7 ng/mL in lumbar disc herniation, 36.5 +/- 18.4 ng/mL in lumbar canal stenosis, and 13.4 +/- 7.48 ng/mL in scoliosis. The concentrations of CD-RAP in cervical myelopathy, lumbar canal stenosis, and lumbar disc herniation were significantly higher than in the control group (P < 0.001). CONCLUSIONS: The CD-RAP concentration was low in the control group, whereas it was significantly higher in spinal diseases that cause spinal stenosis. CD-RAP is expressed in cerebrospinal fluid as a result of damage to or stressing of neural structures and could be a marker for spinal diseases.

Adolescent↗
PubMed2001

Proliferative activity of the parathyroid cells in rats with secondary hyperparathyroidism.

Proliferative kinetics of parathyroid cells in secondary hyperparathyroidism (HPT) are still unknown. We examined the histopathological changes and proliferative activity of parathyroid cells in spontaneously hypercholesterolemic (SHC) rats that exhibit secondary HPT and in normal Sprague Dawley (SD) rats from 3 weeks to 32 weeks of age. Proliferative activity [proliferating cell nuclear antigen(PCNA) labeling index], evaluated by means of immunohistochemical examination of PCNA, declined in SD rats with age from 10.8% at 3 weeks of age to 0.15% at 32 weeks of age. In SHC rats, a PCNA labeling index of 11.6% declined to 3.12% at 14 weeks of age and rebounded to 6.15% at 26 weeks of age. Parathyroid glands increased in size as determined by the maximum cross-sectional area, but in SHC rats, the increase was significantly greater, paralleling the progression of renal dysfunction, and at 32 weeks they were almost three times larger than in SD rats. Parathyroid hormone (PTH) levels in SHC rats also rose sharply after 20 weeks and reached 611 pg/ml at 32 weeks, while PTH in SD rats remained unchanged at approximately 110 pg/ml. This study showed that in the course of developing HPT in SHC rats, there is a large increase in the size of the parathyroid gland, a concomitant increase in PTH levels, and a PCNA labeling index that is higher than in normal SD rats.

Animals↗
PubMed2001

Soy product intake and premenopausal hysterectomy in a follow-up study of Japanese women.

OBJECTIVE: The estrogenicity of dietary soy may increase the risk of diseases, such as uterine leiomyoma and endometriosis, which originate from uterine tissue and are predominant indications for hysterectomy. We sought to determine whether soy product intake is associated with an increased risk of premenopausal hysterectomy. DESIGN: Prospective cohort study. SETTING: Takayama City, Gifu, Japan. SUBJECTS: A cohort of 1172 female residents randomly selected from participants in the Takayama Study who were aged 35-54 and premenopausal at the time they entered the study in 1992. MEASUREMENTS: Diet including soy product and isoflavone intake was assessed by a validated semiquantitative food frequency questionnaire at baseline. Information on the onset of menopause and hysterectomy were obtained by a follow-up mail questionnaire in 1998. RESULTS: During the 6 y study period, 31 women underwent premenopausal hysterectomies. The second tertile of isoflavone intake was significantly associated with an decreased risk of premenopausal hysterectomy compared to the lowest tertile of intake after controlling for age and total energy (rate ratio=0.35, 95% confidence interval 0.13-0.97), although the dose-response relationship was not statistically significant. CONCLUSIONS: It is possible that soy product intake may be inversely associated with diagnoses leading to hysterectomy. Future studies focusing on specific diseases will be required to examine this possibility. SPONSORSHIP: Grants from the Ministry of Education, Science, Sports and Culture, Japan.

Adult↗
PubMed2001

Distinct functions of the two protein tyrosine phosphatase domains of LAR (leukocyte common antigen-related) on tyrosine dephosphorylation of insulin receptor.

Most receptor-like, transmembrane protein tyrosine phosphatases (PTPases), such as CD45 and the leukocyte common antigen-related (LAR) molecule, have two tandemly repeated PTPase domains in the cytoplasmic segment. The role of each PTPase domain in mediating PTPase activity remains unclear; however, it has been proposed that PTPase activity is associated with only the first of the two domains, PTPase domain 1, and the membrane-distal PTPase domain 2, which has no catalytic activity, would regulate substrate specificity. In this paper, we examine the function of each PTPase domain of LAR in vivo using a potential physiological substrate, namely insulin receptor, and LAR mutant proteins in which the conserved cysteine residue was changed to a serine residue in the active site of either or both PTPase domains. LAR associated with and preferentially dephosphorylated the insulin receptor that was tyrosine phosphorylated by insulin stimulation. Its association was mediated by PTPase domain 2, because the mutation of Cys-1813 to Ser in domain 2 resulted in weakening of the association. The Cys-1522 to Ser mutant protein, which is defective in the LAR PTPase domain 1 catalytic site, was tightly associated with tyrosine-phosphorylated insulin receptor, but failed to dephosphorylate it, indicating that LAR PTPase domain 1 is critical for dephosphorylation of tyrosine-phosphorylated insulin receptor. This hypothesis was further confirmed by using LAR mutants in which either PTPase domain 1 or domain 2 was deleted. Moreover, the association of the extracellular domains of both LAR and insulin receptor was supported by using the LAR mutant protein without the two PTPase domains. LAR was phosphorylated by insulin receptor tyrosine kinase and autodephosphorylated by the catalytic activity of the PTPase domain 1. These results indicate that each domain of LAR plays distinct functional roles through phosphorylation and dephosphorylation in vivo.

Animals↗
PubMed2001

[Successful complete androgen blockade (CAB) therapy for prostatic cancer detected from multiple lung metastases: a case report].

Prostatic cancer is rarely diagnosed by detection of lung metastases. We report a case of prostatic cancer in a 73-year-old man detected by abnormalities in chest X-ray and serum prostate specific antigen (PSA) level. He was initially admitted to our hospital due to elevation of PSA level. On the first transperineal prostatic needle biopsy, prostatic cancer was not detected and he was followed. Seven months after the first biopsy, chest X-ray revealed multiple abnormal nodules in the lung fields bilaterally and PSA level was again elevated. A second prostatic biopsy and whole-body examination were performed, and he was diagnosed with moderately differentiated prostatic adenocarcinoma with multiple lung metastases. Complete androgen blockade therapy was performed immediately. Two months after the beginning of treatment, PSA level was normalized and the multiple lung metastases had completely disappeared. There has been no evidence of recurrence or PSA relapse 24 months after detection of the prostatic cancer. This is the 26th case of prostatic cancer diagnosed in Japan following detection of multiple lung metastases.

Adenocarcinoma↗
PubMed2001

[Regional cerebral blood flow values measured by Xe-CT during the attack of transient global amnesia: a case report].

A 50-year-old right-handed woman was referred to our hospital for further examination of sudden global amnesia. The patient had no history of epilepsy, head injury or cerebral vascular diseases. There were no neurological deficits except for recent memory disturbance. We examined her cerebral blood flow(CBF) immediately during transient global amnesia(TGA) by stable xenon enhanced CT scans(Xe-CT) and twice thereafter. Xe-CT during the attack showed a significant diminution of regional blood flow from the right posterior temporal lobe to the occipital lobe. Conventional MRI scans also had been performed serially but it could not detect the local ischemic event. The ischemic lesion was clearly divided and larger than those cases reported using PET, SPECT, and diffusion-weighted MRI. TGA happens suddenly, and recovery is immediate. It becomes very difficult to study CBF during TGA attack. However stable Xe-CT is capable of examining CBF easily, so we concluded that CBF examination by Xe-CT in TGA patients would be helpful to reveal the mechanism of TGA.

Amnesia, Transient Global↗
PubMed2000

Association of diet with the onset of menopause in Japanese women.

A prospective study was conducted in Takayama, Gifu, Japan, to evaluate the association between diet and the onset of menopause. A total of 1,130 female residents aged 35-54 years who were premenopausal and completed a validated semiquantitative food frequency questionnaire in 1992 were contacted by mail with a follow-up questionnaire in 1998 to update information on menopause. Onset of menopause was defined as a woman's age at the last menstrual period prior to stopping menstruation for 12 months. During the 6-year study period, 296 women experienced natural menopause. The Cox proportional hazards model was used to estimate hazard ratios of the onset of menopause after controlling for age, total energy, body mass index, years of smoking, and age at which regular menstrual cycle began. The authors found that green and yellow vegetable intake was significantly inversely associated with the 6-year incidence of menopause (hazard ratio = 0.71, 95% confidence interval: 0.54, 0.95 for the highest vs. lowest tertile of intake, p for trend = 0.02). Association of carotene intake with the incidence of menopause was of borderline significance (hazard ratio = 0.78, 95% confidence interval: 0.59, 1.04, p for trend = 0.07).

Adult↗
PubMed2000

On-line automated high-performance liquid chromatographic determination of total riboflavin phosphates using immobilized acid phosphatase as a pre-column reactor.

An automated chromatographic detection system for the determination of total riboflavin phosphates using immobilized sweet potato acid phosphatase as a pre-column reactor is reported on. An immobilized enzyme reactor, incorporated in the on-line analytical system, hydrolysed riboflavin phosphates to riboflavin, and then lipophilic riboflavin was concentrated at the top of an ODS trap column. Enzymatically hydrolysed riboflavin was back-eluted from the trap column using a mobile phase containing methanol, and then subsequently chromatographed on an ODS analytical column. The effluents were monitored by UV absorption at 280 nm. The calibration graph for total riboflavin phosphates, determined by this method, was linear over the range 0.5-500 nmol/ml, with a correlation coefficient of 0.9999. The detection limit at a signal-to-noise ratio of 3 was 25 pmol/ml. The average conversion rate of riboflavin phosphates to riboflavin was estimated at 97%. The relative standard deviations of the intra- and inter-assay precision were 1.2 and 2.6%, respectively.

Acid Phosphatase↗
PubMed2000

Identification of a functional transposase of the Tol2 element, an Ac-like element from the Japanese medaka fish, and its transposition in the zebrafish germ lineage.

The Tol2 element of the medaka fish Oryzias latipes belongs to the hAT family of transposons (hobo/Ac/Tam3). We report here identification of a functional transposase of Tol2 that is capable of catalyzing its transposition in the germ line of zebrafish Danio rerio. A transcript produced from Tol2 encodes a putative transposase. Zebrafish fertilized eggs were coinjected with mRNA transcribed in vitro, using cDNA of the Tol2 transcript as a template and a plasmid DNA harboring a mutant Tol2, which had a deletion in the putative transposase gene but retained necessary cis sequences. The injected fish were raised to adulthood and mated to noninjected fish, and genomic DNA of the progeny fish were analyzed by PCR and Southern hybridization. Half of F(1) fish obtained from one of eight injected fish contained the Tol2 DNA in their genomes but not the vector portion. Among these F(1) fish, Tol2 insertions at four different loci were identified, and some F(1) fish carried two or three different Tol2 insertions, indicating that the germ line of the founder fish is highly mosaic. Sequencing analyses revealed that, in all cases, Tol2 was surrounded by zebrafish genomic sequences, and an 8-bp duplication was created at the target site, indicating that Tol2 was integrated in the zebrafish genome through transposition. This study identifies an autonomous member of a DNA-based transposable element from a vertebrate genome. The Tol2 transposon system should thus be used to develop novel transgenesis and insertional mutagenesis methods in zebrafish and possibly in other fishes.

Animals↗
PubMed2000

Activation of NADPH oxidase in Alzheimer's disease brains.

The present study is the first to show that superoxide (O(-)(2)) forming NADPH oxidase is activated in Alzheimer's disease (AD) brains by demonstrating the marked translocation of the cytosolic factors p47-phox and p67-phox to the membrane. In conjunction with a recent in vitro study showing that amyloid beta activates O(-)(2) forming NADPH oxidase in microglia, where these phox proteins are localized in this study, the present results suggest that, in AD, NADPH oxidase is activated in microglia, resulting in the formation of reactive oxygen species which can be toxic to neighboring neurons in AD.

Aged↗
PubMed2000

Quantum phase transitions in the shastry-sutherland model for SrCu2(BO3)(2)

We investigate quantum phase transitions in the frustrated antiferromagnetic Heisenberg model for SrCu2(BO3)(2) by using the series expansion method. It is found that a novel spin-gap phase, adiabatically connected to the plaquette-singlet phase, exists between the dimer and the magnetically ordered phases known thus far. When the ratio of the competing exchange couplings alpha( = J'/J) is varied, this spin-gap phase exhibits a first- (second-) order quantum phase transition to the dimer (the magnetically ordered) phase at the critical point alpha(c1) = 0.677(2) [ alpha(c2) = 0. 86(1)]. Our results shed light on some controversial arguments about the nature of quantum phase transitions in this model.

Journal Article↗
PubMed2000

Lumbopelvic lordosis and pelvic balance on repeated standing lateral radiographs of adult volunteers and untreated patients with constant low back pain.

STUDY DESIGN: Twenty volunteers and 20 patients with no prior spine surgery had two standing lateral radiographs taken, on the average, 66 months apart and 2 weeks apart, respectively. OBJECTIVES: To first determine the reliability of the measurement techniques used, and then the longitudinal variation between radiographs for the sagittal spinopelvic alignments measured in two stable populations, the one manifesting no back symptoms (volunteers) and the other showing no changes in symptoms (patients). Pelvic morphology also was assessed quantitatively, and significant correlations for the measurements were studied. SUMMARY OF BACKGROUND DATA: There are no published studies on longitudinal variation for measurements of sagittal spinal alignments in asymptomatic control subjects or untreated patients with stable back problems. It may be helpful to know not only how much variation in alignments can be expected between radiographs of the same individual, but also which measurements and measurement techniques offer the greatest clinical reliability and application. METHODS: Each patient in this study reported mechanical type low back pain that was constant in location and character as well as clinically consistent with symptomatic degenerative lumbar disc disease. Each patient and volunteer had 36-inch-long lateral radiographs taken of the entire thoracic and lumbar spine, which included the pelvis. After intervening periods of 1 to 4 weeks (patients) and 5 to 6 years (volunteers), a second radiograph was taken for comparison. Two observers made 24 different measurements on the radiographs including determinations for lumbopelvic lordosis, pelvic balance, and pelvic morphology using the pelvic radius technique. Reliabilities, longitudinal variations, and correlations for the measurements were compared. RESULTS: The most reliable measurements were for pelvic morphology, pelvic balance, and regional lumbopelvic lordosis by the pelvic radius technique. Pelvic morphology was the most constant measurement between individual radiographs. Pelvic morphology and total lumbosacral lordosis were dependent measurements that were complementary in determining total lumbopelvic lordosis. Lumbopelvic lordosis and pelvic balance also had strong correlation, whereas lumbosacral lordosis and pelvic balance were independent measurements. CONCLUSIONS: The pelvic radius technique is recommended for evaluating lordosis to the pelvis because this approach provided not only good measurement reliability on standing radiographs for lumbopelvic lordosis, but also determination of pelvic balance over the hips and the option to assess pelvic morphology quantitatively. Lumbopelvic lordosis and pelvic balance were strongly correlative. This finding, along with higher reliability and lower longitudinal variation on repeated radiographs, indicated greater clinical application for these specific measurements.

Adult↗
PubMed2000

Hypocholesterolemic effect of soymilk supplementation with usual diet in premenopausal normolipidemic Japanese women.

BACKGROUND: The hypocholesterolemic effect of soy protein concentrates on normolipidemic subjects still remains unclear. Our objective is to assess the effect of soymilk supplementation, a whole soy product, with usual diet on serum lipids in normolipidemic subjects. METHODS: We conducted a randomized controlled trial on 60 premenopausal normolipidemic Japanese women. After excluding 8 subjects whose initial serum concentration of total cholesterol or triacylglycerol was higher than 220 mg/dL (5.69 mmol/L) or 160 mg/dL (1.81 mmol/L), respectively, we encouraged the subjects in the soymilk-supplemented group (n = 27) to consume 400 mL (408 g) of commercial regular soymilk daily during two menstrual cycles. There were no significant differences in variables, including nutrient intake, between the soymilk-supplemented and control (n = 25) groups before the intervention. RESULTS: After the trial, we observed a significant decrease of 10.9 mg/dL, or 5.3%, in serum concentration of total cholesterol in the soymilk-supplemented group. During the intervention, nutrient intake assessment showed significant increases in nutrient densities of vitamin E, polyunsaturated fatty acids, isoflavones, and P/S ratio and decreases in total energy and nutrient densities of vitamin C and green tea in this group. A statistically significant decrease in serum total cholesterol could still be observed even after excluding the estimated hypocholesterolemic effects of soymilk's polyunsaturated fatty acids. CONCLUSIONS: Our results suggest the hypocholesterolemic effect of soymilk, a traditional whole soy product, in Asian countries in normolipidemic subjects.

Adult↗
PubMed2000

Rationality/antiemotionality personality and selected chronic diseases in a community population in Japan.

OBJECTIVE: To clarify the relationships of the rationality/antiemotionality (R/A) personality with past histories of seven chronic diseases and current smoking habits in a community population in Japan. METHODS: A questionnaire survey was conducted of all residents aged 35 years old or over (n = 37,287) in Takayama city, Gifu prefecture, Japan; the response rate was 90.3%. Data from 13,091 males and 14,061 females who completed all relevant questions were analyzed. The subjects were asked to complete an 11-item R/A personality scale developed by Grossarth-Maticek et al. (1985). Past histories of seven major chronic diseases and current smoking habit were also asked in the questionnaire. RESULTS: Among males, the R/A scale score was significantly lower in those who had stroke, diabetes or allergy than in those who did not. Among females, the R/A scale score was significantly lower in those who had stroke, allergy or stomach cancer than in those who did not. Among females, current smokers had significantly lower R/A scores than non-smokers. After controlling for age, smoking and drinking, the R/A score was significantly and negatively associated with stroke among males and females; it was significantly and negatively associated with diabetes and allergy among males. CONCLUSION: Our findings are contrary to those observed in Yugoslavia and West Germany, and suggest a cultural difference in the relationship between the R/A personality and disease occurrence.

Adult↗
PubMed2000

Temperature-dependent translational regulation of the ER omega-3 fatty acid desaturase gene in wheat root tips.

The proportion of alpha-linolenic acid (18:3) among the total fatty acids in root tissue increases as the growth temperature decreases. Endoplasmic reticulum omega-3 fatty acid desaturase is responsible for the production of most of the 18:3 in root tissue. In this study, the effect of temperature on expression of the TaFAD3 gene, which encodes endoplasmic reticulum omega-3 desaturase in wheat (Triticum aestivum L. cv. Chihoku), was analysed at the mRNA and protein levels. In wheat root tips grown at 30 and 10 degrees C, the proportions of 18:3 among total fatty acids were 22% and 55%, respectively. The level of TaFAD3 protein in microsomal preparations of the root tips grown at 10 degrees C was approximately 7.5 times higher than that of the root tips grown at 30 degrees C. The increased level of TaFAD3 protein at the lower temperature was accompanied by enhanced association of TaFAD3 mRNA with polyribosomes. In contrast, the level of TaFAD3 mRNA in root tips grown at 10 degrees C was slightly higher than in those grown at 30 degrees C. These results suggest that, in root tips, the increase in the 18:3 level at low temperature is achieved directly by an increase in the amount of TaFAD3 protein, and that temperature-dependent translational regulation of the TaFAD3 gene, rather than its transcriptional regulation, contributes to modulation of the TaFAD3 protein accumulation.

Endoplasmic Reticulum↗