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M Morita

Publications and source records attributed to M Morita.

At least 91 records · Page 5Linked to original sources
PubMed2001

Lactone formation of N-acetylneuraminic acid oligomers and polymers as examined by capillary electrophoresis.

We examined lactone-formation reaction of oligomers and polymers of N-acetylneuraminic acid in diluted hydrochloric acid solution and found that the time course of the lactonization reaction was easily traced by capillary electrophoresis. The reaction proceeded more rapidly with increasing the molecular mass of oligomers because the conformation of inner units became rigid and more favorable for the formation of lactone linkage. Present results obtained using capillary electrophoresis will be useful in understanding of physical and chemical properties of oligo/polysialic acids.

Carbohydrate Sequence↗
PubMed2001

Discordant iodine-123 metaiodobenzylguanidine uptake area reflects recovery time dispersion in acute myocardial infarction.

lodine-123 metaiodobenzylguanidine (MIBG) uptake was reported to be reduced compared to Tl-201 (Tl) in acute myocardial infarction (AMI). Within such an area, degrees of both sympathetic neural function and ischemic myocardial cell damage are considered to be greatly dispersed. These kinds of damage were reported to effect reporalization time in myocardial cells, and we evaluated our hypothesis that extension of the discordant MIBG uptake area correlates with recovery time (RT) dispersion and relate ventricular arrhythmias in AMI. MIBG and Tl images were obtained in AMI patients. Regional Tl or MIBG uptake was estimated in 9 segments of SPECT by using four-point scoring. The total score was the sum of scores in 9 SPECT segments. ATI-MIBG was calculated by subtracting the total MIBG score from the total Tl score. Corrected RT (RTc) was measured as a signal-averaged ECG. RTc dispersion was defined as the difference between maximal and minimal RTc. The patients were assigned to two groups (group A; < or = Lown 4a, group B; > or = Lown 4b) according to the results of 24-hour Holter monitoring. A positive correlation between RTc dispersion and ATI-MIBG was found. ATI-MIBG and RTc dispersion in group B were greater than those in group A. These results suggested that ATI-MIBG could be used to predict the development of malignant ventricular arrhythmias.

3-Iodobenzylguanidine↗
PubMed2001

Hip-shelf procedure in the treatment of osteonecrosis of the transpositioned acetabulum after rotational acetabular osteotomy.

Necrosis of the transpositioned acetabulum after rotational acetabular osteotomy (RAO) is a major complication characteristic of this procedure. This complication, although rare, has been thought difficult to treat. We report a patient with acetabular osteonecrosis and subsequent collapse after RAO that was effectively treated with a shelf operation, providing satisfactory remodeling of the hip joint. A 16-year-old female had undergone RAO for the treatment of developmental acetabular dysplasia. Postoperative radiography showed that the osteotomized acetabular fragment was unusually thin, and that the osteotome entered the hip joint during the surgery. Five months after the RAO, X-rays revealed significant collapse of the transpositioned acetabulum, and femoral head subluxation caused by postoperative osteonecrosis. Seven months after the RAO, the patient underwent a hip-shelf procedure. The remaining acetabular fragment was used in this procedure, according to the Spitzy method. Seven years after the second operation, favorable remodeling of the hip joint was observed; however, early osteoarthritic changes, including slight joint space narrowing, bone sclerosis of the new acetabulum, and bone cysts within the femoral head, were seen.

Acetabulum↗
PubMed2001

Effects of dioxins and polychlorinated biphenyls (PCBs) on thyroid function in infants born in Japan--the second report from research on environmental health.

Dioxins (PCDD + PCDF) and polychlorinated biphenyl (PCB) are potentially hazardous compounds and have structural similarity to thyroid hormones. Our research group on "Dioxins and PCB in Human Milk" was organized in 1997 and has been active for the past three years. We collected breast milk from 80 mothers living in Tokyo, Saitama, Ishikawa and Osaka Prefecture in Japan at 5, 30, 150, 300 postpartum days and measured PCDDs, PCDFs and PCBs during 1998-1999. We added another 20 prefectures and cities during 1999-2000. Breast milk was obtained from 415 mothers at 30 postpartum days (breast-feeding group). Blood was taken from infants who were breast-fed at the age of 1 year for evaluation of thyroid and immune functions. Blood was also taken from 53 infants who were bottle-fed (bottle-feeding group) as a control. Serum T4, T3, FT4 and TSH levels in the breast-feeding (n = 337) and bottle-feeding (n = 53) groups were within normal ranges and were not significantly different between the two groups. Although there were a large geographic differences of dioxins and co-PCB content in breast milk, there were no differences in serum T4, T3, FT4, TSH levels and no significant correlation between the mean serum levels of TSH and TEQ in breast milk. There was a significant correlation between serum TSH at 1 year of age and that from blood on dried filter paper TSH at 5 days of age. We concluded that dioxin intake from breast milk in Japanese infants did not impair thyroid function. However, long-term effects remain to be evaluated.

Adult↗
PubMed2001

Effects of the quantity of water and milk ingested concomitantly with AS-924, a novel ester-type cephem antibiotic, on its pharmacokinetics.

The effect of the quantity of water ingested concomitantly with drugs, on the absorption of AS-924, a novel prodrug-type cephem antibiotic, was studied in five healthy adult volunteers by a cross-over method, using cefteram-pivoxil (CTER-PI) as the control drug. In addition, the effect of milk on the absorption of AS-924 was also investigated. The absorption of CTER-PI was significantly reduced when administered together with 30 ml of water compared with its absorption when administered together with 150 ml of water, whereas no such reduction was found in the case of AS-924. Ingestion of milk did not significantly affect the absorption of AS-924. These results confirm that absorption of AS-924 after oral administration is not likely to be affected by the quantity of water taken concomitantly with the drug, nor by milk.

Administration, Oral↗
PubMed2001

Regional differences in homicide patterns in five areas of Japan.

This article describes regional differences in the homicide patterns which occurred in Sapporo City and the surrounding area, and in Akita, Ibaraki, Chiba and Toyama prefectures in Japan. Information collected from each case of homicide included factors such as age, sex of the victim and assailant, causes of death, disposition of the offender, relationship between assailant and victim, reasons for criminal action, et al. The statistical features of homicidal episodes among the five different regions showed considerable variation, as follows. The mean death rates for homicide (number of victims per 100,000 of population) during the period 1986-1995 were 0.44 (Sapporo), 0.8 (Akita), 0.58 (Toyama), 0.7 (Ibaraki) and 0.75 (Chiba), respectively. Close family relationship between the victim and assailant was observed in the homicidal acts which occurred in Sapporo, Akita and Toyama. Assailant's relationship to victim was commonly extra-familial in Ibaraki and Chiba-neighboring megalopolis Tokyo, where some events of murder by a foreigner occurred. Homicide by female assailant, murder by mentally abnormal killers and homicide-suicide events were closely associated with family members. And these factors contributed to the considerable number of victims in Sapporo, Akita and Toyama. But, this close family relationship of the victim to the assailant did not correspond with the elevation in the number of deaths, and it was rather inversely related to the higher death rates recognized in Ibaraki and Chiba. This comparative study suggested that rapid urbanization considerably affects regional differences in homicide patterns.

Journal Article↗
PubMed2001

Assessment of newly developed tongue sulfide probe for detecting oral malodor.

AIM: The present study examined the relationship between sulfide levels on tongue dorsum surfaces (pS levels) and oral malodor. METHOD: The pS levels of 20 systemically healthy volunteers were evaluated using an industrial device equipped with a newly-developed tongue sulfide probe. The pS levels on 3 parts of the tongue--anterior, middle and posterior along the median groove of the tongue dorsum--were determined for each subject. RESULTS: The device reported the pS level in a digital score ranging from 0.0 (< 10(-7) M of sulfide) to 5.0 (> or = 10(-2) M of sulfide) in increments of 0.5. Oral malodor was assessed by measuring the level of volatile sulfur compounds in mouth air, as well as by the organoleptic method. The pS levels were 0.03 +/- 0.11, 0.20 +/- 0.41 and 0.88 +/- 0.76 for the anterior, middle and posterior parts, respectively. This difference was significant (p<0.001). Both oral malodor measurements showed significant correlation (p<0.05) with the pS levels of middle and posterior parts of tongue. CONCLUSION: It was concluded that the tongue sulfide probe might be useful in management of subjects with oral malodor.

Adult↗
PubMed2001

Association between oral malodor and adult periodontitis: a review.

BACKGROUND: Bad breath has a significant impact on our daily social life to those who suffer from it. The majority of bad breath originates within the oral cavity. However, it is also possible that it can come from other sources such as gastric-intestine imbalance. The term "oral malodor" is used to describe a foul or offensive odor emanating from the oral cavity, in which proteolysis, metabolic products of the desquamating cell, and bacterial putrefaction are involved. Recent evidence has demonstrated a link between oral malodor and adult periodontitis. The process of developing bad breath is similar to that noted in the progression of gingivitis/periodontitis. Oral malodor is mainly attributed to volatile sulfur compounds (VSC) such as hydrogen sulfide, methyl mercaptan and dimethyl sulfide. The primary causative microbes are gram-negative, anaerobic bacteria that are similar to the bacteria causing periodontitis. These bacteria produce the VSC by metabolizing different cells/tissues (i.e., epithelial cells, leukocytes, etc.) located in saliva, dental plaque, and gingival crevicular fluid. Tongue surface is composed of blood components, nutrients, large amounts of desquamated epithelial cells and bacteria, suggesting that it has the proteolytic and putrefactive capacity to produce VSC. One of the challenges in dealing with oral malodor is to identify a reliable test for detecting bad breath. AIMS: The purposes of this review article were: (1) to correlate the relationship between oral malodor and adult periodontitis; (2) to analyze current malodor tests and discuss available treatment regimens.

Adult↗
PubMed2001

Defective development of secretory neurones in the hypothalamus of Arnt2-knockout mice.

BACKGROUND: Within the basic region-helix-loop-helix (bHLH)-PAS family of transcription factors, Arnt and Arnt2 play unique roles; these two factors not only heterodimerize with themselves, but also with other members of this family and they act as transcription regulators which bind to specific DNA elements. Whereas Arnt is broadly expressed in various tissues, the expression of Arnt2 is known to be limited to the neural tissues. RESULTS: To elucidate the function of Arnt2 in detail, we cloned the mouse Arnt2 gene and its gene structure was determined. We subsequently generated germ line Arnt2 mutant mice by gene targeting technology. Heterozygous Arnt2 mice were viable, but homozygous Arnt2 gene knockout mice died shortly after birth. Histological and immunological analyses revealed that the supraoptic nuclei (SON) and the paraventricular nuclei (PVN) are hypocellular. Moreover, secretory neurones identified by the expression of neurosecretory hormone such as arginine vasopressin, oxytocin, corticotrophin-releasing hormone and somatostatin are completely absent in SON and PVN in the mutant Arnt2 mice. Consistent with these observations, prospective SON and PVN neurones which express Brn2 appeared around E13.5 in the mantle zone, but no neurones which expressed the neurosecretory hormones were found in the SON and PVN regions. CONCLUSIONS: These data show that the transcription factor Arnt2 controls the development of the secretory neurones at the later or final stages of differentiation rather than at the beginning stage. Strikingly similar observations have been reported with the Sim1 deficient mice. Taken together, our results demonstrate that Arnt2 is an indispensable transcription factor for the development of the hypothalamus, and suggest that Arnt2 is an obligatory partner molecule of Sim1 in the developmental process of the neuroendocrinological cell lineages.

Amino Acid Sequence↗
PubMed2001

Comparison of Japanese general rules of prostatic cancer and Gleason grading system.

BACKGROUND: We compared the prognostic efficacy between the Japanese General Rules of Prostatic Cancer (JGRPC) and the Gleason grading system (GGS) by applying them to a single set of patients and assessing the survival outcome. METHODS: One hundred and seventy-six patients with previously untreated prostate cancer were studied. One experienced Japanese pathologist graded the slides with JGRPC. Another experienced American pathologist graded the same slides with the Gleason grading system. The JGRPC grades were correlated with the Gleason scores (GS) grouped into three (GS 2-4, 5-7 and 8-10) or four (GS 2-4, 5-6, 7 and 8-10) tiers. RESULTS: The highest cancer death rates were seen in the higher grade groups in both systems. Comparison of JGRPC grade and three-tiered grouping of the GS showed identical grades in 81 of 176 cases (46.0%). The overall kappa value of agreement was only 0.151. The 96 cases of JGRPC moderately differentiated carcinoma group contained two nearly equal-sized groups by the Gleason grading system, those with GS 5-7 (47cases) and GS 8-10 (49 cases). There was a significant difference in survival rate between the GS 5-7 and GS 8-10 groups. No significant differences were noted in the reverse analysis of survival by JGRPC groups within patients with the same GS three-tiered groups. Similar trends were seen when JGRPC was compared with the four-tiered grouping of the GS. CONCLUSION: Both JGRPC and the Gleason grading system are useful in estimating the prognosis of prostate cancer, but only a mild correlation was found between the two systems. The Gleason grading system may provide more prognostic information than JGRPC in the moderately differentiated group.

Adenocarcinoma↗
PubMed2001

Postnatal growth of the rat palatine gland.

To elucidate how the palatine glands grow postnatally, the palatine glands of rats from 0 to 8 weeks of age were investigated histologically and immunohistochemically. Under light microscope, three dimensions of the right part of the palatine glands were measured and the total number of excretory ducts of the glands was counted from the parasagittal serial sections. Immunohistochemistry with anti-5-bromo-2'-deoxyuridine (BrdU) monoclonal antibody was also employed to detect the cellular proliferative activity. At birth (0 weeks), the palatine glands consisted of ducts and immature acini. The ducts in the glands were connected with excretory ducts. After 2 weeks, there was no duct in the glands. Most acinar cells became mature as mucous cells and took the form of tubulo-acini connected directly with excretory ducts. In the posterior region of the glands, serous acinar cells forming demilunes were occasionally seen. All three dimensions of the palatine glands became longer, and the number of excretory ducts tended to increase. Immunohistochemistry showed acinar and duct cells were highly proliferative in early stage of postnatal life and their proliferative activity decreased thereafter. This study demonstrated that immature rat palatine glands of newborn rats grow three-dimensionally during maturation, and that the parenchymal cell proliferation contributes to the growth of the rat palatine glands. In addition, it is suggested that the glandular tissue arises from the excretory ducts formed postnatally.

Animals↗
PubMed2001

Expression of arginine vasopressin and vasopressin V1a receptor mRNA in diabetic (db/db) mice.

To assess the involvement of arginine vasopressin (AVP) in genetical diabetic (db/db) mice, we examined the mRNA expression levels of AVP and vasopressin V(1a) receptors (V(1a)R) in brain and liver of db/db mice. In 10 week-old db/db mice, a significant elevation in blood sugar levels and plasma osmolality were observed, showing obvious diabetic symptoms. There was a significant increase in brain AVP mRNA levels in db/db mice. The expression level of liver V(1a)R mRNA in db/db mice was significantly down-regulated, presumably as a consequence of ligand-receptor interaction. This is in contrast to results that show no significant reduction in brain V(1a)R mRNA levels when comparing db/db and control mice. Thus, it is possible that in the progress of genetic diabetes mellitus, AVP acts in liver than in brain through V(1a)R.

Animals↗
PubMed2001

A case-control study on food intake of patients with recurrent aphthous stomatitis.

OBJECTIVE: This study compared food intake among patients with recurrent aphthous stomatitis (RAS) and control patients. STUDY DESIGN: A total of 2129 outpatients of a dental hospital were enrolled. Of these, 118 patients reporting RAS experiences 4 times or more during the past year (RAS group) were selected with age-matched and sex-matched control patients. The patients filled out a questionnaire about the frequency intake of 33 foods. RESULTS: Principal component factor analysis extracted 2 food intake patterns (Factor I and II). The factor weight for Factor I showed a significantly positive correlation with consumption ratios of calcium, iron, vitamin B1, and vitamin C intake to total daily intake. The median factor score for Factor I, which was calculated based on the factor weight, was significantly lower in the patients with RAS than that in the controls. CONCLUSION: We hypothesize that not only iron and vitamin B1 might be deficient in these patients but also calcium and vitamin C.

Adult↗
PubMed2001

Immunocytochemistry of glutathione S-transferase in taste bud cells of rat circumvallate and foliate papillae.

Immunocytochemistry was used to investigate the distribution of cells reacting with specific antibodies against glutathione S-transferase (GST) mu and pi in rat circumvallate and foliate taste buds; the findings were confirmed by Western blotting. Double immunofluorescence staining for protein gene product (PGP) 9.5 and GST subunits allowed the classification of taste bud cells of both papillae into: (i) cells immunoreactive to either PGP 9.5 or GST subunit antibody; (ii) cells immunoreactive to both antibodies; and (iii) cells that did not react with either of these antibodies. Immunoelectron microscopy revealed that most GST subunit-immunoreactive cells seemed to be either type II or type III cells based on their ultrastructure. Since PGP 9.5 is now widely used as a marker for type III cells in mammalian taste buds, it seems reasonable to believe that most GST subunit-immunoreactive cells are type II cells. Whether cells immunoreactive for both PGP 9.5 and GST subunits constitute a small subpopulation of type III cells or whether they are intermediate forms between type II and III cells is under investigation. No type I cells reacted with antibodies against GST subunits in the present study. GST subunits in taste bud cells may participate in xenobiotic metabolism of certain substances exposed to taste pits, as already shown for olfactory epithelium.

Animals↗
PubMed2001

Effects of deoxycholic acid and its epimers on lipid peroxidation in isolated rat hepatocytes.

We studied the effects of deoxycholic acid and its three epimers with beta-hydroxyl groups (3alpha,12beta-, 3beta,12alpha-, and 3beta,12beta-dihydroxy-5beta-cholan-24-oic acids), which were hydrophilic and less cytotoxic, on lipid peroxidation to elucidate the relationship between structural features of bile acids and their effect on lipid peroxidation. Taurodeoxycholate markedly increased the production of thiobarbituric acid-reactive substances, end products of lipid peroxidation, in isolated rat hepatocytes, whereas epimers of taurodeoxycholate did not. Deoxycholic acid inhibited mitochondrial NADH dehydrogenase and NADH:ferricytochrome c oxidoreductase activities, leading to free radical generation, whereas epimers of deoxycholic acid had no effect on mitochondrial enzymes. These findings suggested that hydrophobic bile acids cause lipid peroxidation by impairment of mitochondrial function, leading to the generation of free radicals; and epimerization of alpha-hydroxyl groups in the steroid nucleus to beta-hydroxyl groups results in a decrease of the toxic effects of deoxycholic acid on lipid peroxidation.

Animals↗
PubMed2001

Mechanism of AVP release and synthesis in chronic salt-loaded rats.

Arginine vasopressin (AVP) is involved in osmotic regulation in the brain and peripheral tissues. To elucidate the regulatory mechanism that involves AVP release in hyperosmolality, we investigated the regulation of the synthesis and release of AVP in chronic salt-loaded rats. In chronic salt-loaded rats, which were generated by free access to water containing 2% NaCl for 7 days, plasma osmolality was significantly increased compared with control value. When tested, the AVP content was significantly higher in plasma but lower in the pituitary and whole brain (hypothalamus, cortex and striatum) than in control rats. The expression of AVP mRNA in the brain was significantly up-regulated compared with that in control rats. These data lead to the suggestion that hyperosmolality stimulates AVP release from the brain and subsequently induces AVP synthesis in the brain. On the other hand, mRNA levels of vasopressin V1a receptor (V1aR), whose down-regulation is known to be a counteraction to the V1aR activation, was not changed in the brain, suggesting that the AVP seems not to interact with the V1aR in the brain. These results suggest that hyperosmosis promotes the release of AVP into plasma, the subsequent induction of AVP mRNA in the brain and its action on the peripheral tissues.

Animals↗
PubMed2001

Antibacterial activity of Bacillus amyloliquefaciens phage endolysin without holin conjugation.

To characterize the enzymatic activity and antibacterial activity of endolysin encoded by a Bacillus amyloliquefaciens phage, the open reading frame encoding endolysin was amplified by PCR and cloned into the expression plasmid pET21d(+). The resultant plasmid was used to transform Escherichia coli JM109(DE3). Production of endolysin in the cytosol facilitated cell lysis without coproduction of holin, which is considered to degrade or alter the cytoplasmic membrane. The phage endolysin was overexpressed and purified. Although the specific activity of the purified phage endolysin towards lyophilized Micrococcus luteus cells was 1/11 of the activity of chicken egg white lysozymes, the endolysin showed stronger antibacterial activity towards E. coli W3110, E. coli JM109(DE3) and Pseudomonas aeruginosa PAO1 than chicken egg white lysozymes. The antibacterial activity of the endolysin towards these three bacterial strains was marked when EDTA was added to the endolysin solution.

Journal Article↗