Biomedical subjects

A Taguchi

Publications and source records attributed to A Taguchi.

At least 73 records · Page 4Linked to original sources

PubMed1997

Radiographic evaluation of possible etiology of diffuse sclerosing osteomyelitis of the mandible.

To examine the cause and site of origin of diffuse sclerosing osteomyelitis of the mandible, we compared various radiographic findings for the mandibular lesions in 20 patients with diffuse sclerosing osteomyelitis with those in 48 patients with osteomyelitis caused by bacterial infection. In osteomyelitis of infectious origin, a typical radiographic feature was a radiolucent lesion spreading in the cancellous bone, with cortical bone perforation and lamellated periosteal reaction. In diffuse sclerosing osteomyelitis, intermingled sclerotic and osteolytic lesions with solid periosteal reaction or external bone resorption were a common finding, and in some patients the cortical bone was initially affected by the fresh or recurrent lesion. Based on these distinct differences, we suggest that the cause of diffuse sclerosing osteomyelitis is not bacterial infection and that the site of origin is not in the bone but in the periosteum.

Bacterial Infections↗

PubMed1997

Trabecular bone pattern of the mandible. Comparison of panoramic radiography with computed tomography.

OBJECTIVES: To analyse the possible correlation between the trabecular bone pattern of the edentulous mandible visualized by panoramic radiography and the bone mineral density (BMD) measured by computed tomography (CT). METHODS: Panoramic radiography and CT were performed on 28 patients with edentulous mandibles. The trabecular bone pattern of 47 regions on the panoramic radiographs was classified into one of five grades. BMD was measured within circular regions of interest on the axial CT images in the corresponding trabecular area. The gradings were correlated with the CT values using one-way analysis of variance. RESULTS: There was a significant correlation between the grade of the trabecular bone pattern and the BMD (P < 0.0001). CONCLUSION: The proposed classification for the trabecular bone pattern on panoramic radiographs might be a useful aid for the evaluation of the edentulous mandible prior to implant placement.

Adult↗

PubMed1997

Observer agreement in the assessment of mandibular trabecular bone pattern from panoramic radiographs.

OBJECTIVES: To study the observer agreement in the assessment of trabecular pattern of the mandible from panoramic radiographs. METHODS: Seven observers were asked to classify the trabecular pattern of 100 edentulous regions of the mandible in 80 randomly selected panoramic radiographs into one of five grades with the aid of a written description and reference images. Intra- and interobserver agreement was calculated as overall agreement and Kappa index. RESULTS: The intra-observer agreement varied between 65% and 79%. The Kappa index for intra-observer agreement was moderate for three observers and substantial for four. For all seven observers, it varied according to the grade of trabecular bone pattern, but the majority deviated from each other by only one grade. CONCLUSION: The relatively high rates of observer agreement indicate that panoramic radiography can be used for the clinical assessment of the trabecular pattern of the mandible.

Adult↗

PubMed1997

[Comparison of the number of parameters using nonlinear iteration methods for compartment model analysis with 18F-FDG brain PET].

In the analysis of the brain kinetic images with 18F-FDG, compartment models with 3 or 4 parameters and an estimation method of nonlinear least squares (NLS) have been applied. We compared the Simplex method and the modified Marquardt method as an iterative NLS algorithm on the simulation data with variable noise. The estimated k-values were equal in the both algorithms. The calculation with modified Marquardt method was three times faster than that of the Simplex method. The dependence of modified Marquardt estimates on the initial values was larger than that of the Simplex, but the permissible initial value range was wide enough for clinical data. Therefore, the modified Marquardt method was found to be more suitable for the compartment model analysis of 18F-FDG than the Simplex method. We also compared the 3-parameter with 4-parameter models for 45 min and 120 min data acquired after administration. The 3-parameter model was suitable for the 45-minute data acquisition, and the 4-parameter model was suitable for the 120-minute data acquisition.

Algorithms↗

PubMed1997

The alginate reduce the postprandial glycaemic response by forming a gel with dietary calcium in the stomach of the rat.

Soluble dietary fibers include an alginate which reduces the postprandial glycaemic response. We speculated that the cause of the reduction of alginate on the glycaemic response is the gel formation of alginate with dietary calcium in the stomach. The aim of the present study was to confirm our hypothesis and to examine the effect of the sugar composition of alginates on the glycaemic response and the effect of continuous feeding of alginate-containing diet to rats. Diabetic rats were made by injecting streptozotocin (STZ) intravenously. These rats were fed 5 g of the experimental diet with or without sodium alginate and with or without calcium after overnight fasting. In the rats fed the diet containing both alginate and calcium, the postprandial glycaemic response was lower than in the rats fed other diets and gastric contents were retained as gel form. Three beta-d-mannuronic acid (M) to alpha-l-guluronic acid (G) (ratios (M/G 0.5, 1.3, 2.1) of alginates were not associated with the acute glycaemic response in STZ rats. Then, we fed normal rats with an alginate-free or one of three respective alginate-containing diets for 4 weeks. During the first 2 weeks of the feeding period, the total amount of food intake of rats fed the G-rich alginate diet was smaller than that of rats in the other dietary groups. Moreover, the weight of the dorsal abdominal adipose tissue of rats given the G-rich alginate diet was the lowest among the dietary groups. We conclude that the reductive effect of alginate feeding on the postprandial glycaemic response was not caused only by their inherent viscosity, but also by gel formation with dietary calcium in the stomach. Moreover, it is necessary to pay attention to the M/G ratio of alginates for estimating their physiological effect.

Adipose Tissue↗

PubMed1997

Evolutionarily conserved mechanisms regulating neural development: lessons from the development of Drosophila peripheral nervous systems.

Functions of genes regulating the development of Drosophila peripheral nervous systems are summarized herein. These genes can be classified into 6 groups: <1> prepattern genes, <2> proneural genes, <3> neurogenic genes, <4> neuronal precursor genes, <5> neuronal precursor type selector genes, and <6> cell-division and lineage genes. The mechanisms described herein provide excellent paradigms in the regulation of the development of other tissues in Drosophila, as well as in other organisms, including vertebrates. The roles of two different inhibitory mechanisms, i.e. Notch-signaling and Argos, in the development of Drosophila neural precursor cells are also discussed.

Animals↗

PubMed1997

[Anesthetic management of a patient with Duchenne's muscular dystrophy undergoing radical repair for tetralogy of Fallot].

This report describes a 13-month-old-girl with Duchenne's muscular dystrophy (DMD) who had radical repair for tetralogy of Fallot safely. Patients with DMD are considered to be at risk of malignant hyperthermia (MH). Drugs for induction and maintenance were chosen from a list of agents rarely associated with MH. To wash out the inhalation anesthetics from the equipment, oxygen was circulated continuously for 24 hours. Dantrolene sodium was kept readily available in case of MH occurrence. Differential diagnosis during surgery is difficult in term of the episodes of MH and complications of cardiac surgery, as cardiac surgery is also associated with tachycardia, tachyarrhythmias, metabolic asidosis and red colored urine, which are frequently accompanied by MH. Although increased levels of CK, GOT, LDH and myoglobin strongly support the diagnosis of MH, such evidence can only be confirmed after operation. Fortunately, these factors recovered to the normal range without treatment by dantrolene sodium. During the cardiac surgery, treatment of MH may be delayed due to its late confirmation.

Anesthesia, General↗

PubMed1996

Effect of systemic zinc administration on delayed neuronal death in the gerbil hippocampus.

The divalent cation zinc has been reported to possess several physiological properties such as blocking apoptotic cell death through an inhibitory effect on Ca(2+)-Mg2+ endonuclease activity, or modulating the neurotoxicity via glutamate receptor subtypes. In the present study, we investigated the effect of peripherally injected zinc on delayed neuronal death seen in the hippocampus after transient global ischemia, in order to elucidate a possible beneficial role on zinc in ischemic neuronal cell death. Forty-five adult Mongolian gerbils of both sexes underwent transient bilateral clipping of the common carotid arteries for 3 min. In the pretreated animals, ZnCl2 (20 mg/kg) was injected subcutaneously once, 1 h before ischemia (superacute group; n = 6) or twice at 24 and 48 h before ischemia (subacute group; n = 14). Histological survey was carried out 3 days later by in situ DNA fragmentation method and 4 days later by hematoxylin-eosin staining by semiquantatively counting dead neurons in the CA1 sector. Subacute zinc pre-administration significantly reduced the nuclear damage and subsequent neuronal death; however, superacutely pre-administered zinc did not protect hippocampal neurons against ischemia but it did not aggravate the effect of ischemia, either. The present study suggested that transfer of exogenous zinc into the intracellular space is required for neuroprotection, presumably via the anti-endonuclease activity.

Animals↗

PubMed1996

Bifemelane hydrochloride enhances 'ischemic tolerance' phenomenon in gerbil hippocampal CA1 neurons.

Neurons are so vulnerable to ischemic insults that transient forebrain ischemia for 5 min killed most CA1 neurons in the gerbil hippocampus (surviving neurons: 4%). In contrast, 2 days after a nonlethal challenge of 2-min ischemia, 51% of CA1 neurons became resistant to subsequent, otherwise lethal ischemia for 5 min. Bifemelane hydrochloride (20 mg/kg, i.p.), which helps ischemic brain recover from oxidative stress and inhibition of protein synthesis, significantly enhanced the 'ischemic tolerance' phenomenon if injected 1 day after 2-min ischemia: 94% of neurons survived after 5-min ischemia. This finding carries implications for possible preventive treatment following warning signs of transient ischemic attack.

Adaptation, Physiological↗

PubMed1996

Effect of immunosuppressant FK506 on ischemia-induced degeneration of hippocampal neurons in gerbils.

To evaluate the effect of FK506 on delayed neuronal death in gerbils after forebrain ischemia, 84 adult Mongolian gerbils were used in this study. Transient forebrain ischemia was induced by clipping common carotid arteries bilaterally for 5 minutes. One hour after reperfusion we intraperitoneally injected FK506 (1.0 mg/kg), cyclosporin A (CsA) (10.0 mg/kg) or the vehicle solution into each gerbil. In one group, each agent was additionally administered daily 3 more times at 24, 48 and 72 hours after ischemia. The gerbils were killed 4 days or 10 days after transient ischemia, and damage to their hippocampal pyramidal cells was histologically assessed. Additionally, the body temperature was measured following administration of each drug to investigate drug-induced hypothermia. Post-ischemic repeated treatment with FK506 significantly (p < 0.01) reduced degeneration of hippocampal neurons. However, partial treatment did not modify neuronal degeneration. CsA did not show a neuroprotective effect in this study. Drug-induced mild hypothermia (35-37 C) was observed following administration of FK506 or CsA. There was no significant difference in the time course of the body temperature between the FK506 and CsA group. We demonstrated that the repeated FK506 treatment, but not the CsA treatment, reduced ischemia-induced degeneration of hippocampal neurons in gerbils. Although FK506-induced hypothermia might have modified neuronal degeneration, a comparison with CsA indicated that the neuroprotective effect of FK506 was not solely due to hypothermia per se.

Animals↗

PubMed1996

Molecular cloning of novel leucine-rich repeat proteins and their expression in the developing mouse nervous system.

It is well established that leucine-rich repeat (LRR) proteins such as connectin, slit, chaoptin, and Toll have pivotal roles in neuronal development in Drosophila as cell adhesion molecules. However, to date, little information concerning mammalian LRR proteins has been reported. In the present study, we sought LRR proteins of the mouse brain, based on the assumption that fundamental mechanisms are conserved between different species. We screened a neonatal mouse brain cDNA library with a human partial cDNA encoding LRR protein as a probe. We obtained two independent cDNAs encoding LRR proteins, designated NLRR-1 and NLRR-2 (Neuronal Leucine-Rich Repeat proteins). We analyzed the whole sequence of NLRR-1 and partial sequence of NLRR-2. Sequence analysis showed that these two clones are about 60% homologous to each other, and that NLRR-1 protein is a transmembrane protein. Northern blot analysis and in situ hybridization histochemistry showed that both NLRR-1 and NLRR-2 mRNAs were expressed primarily in the central nervous system (CNS); NLRR-1 mRNA was also detected in the non-neuronal tissues such as cartilage, while NLRR-2 mRNA expression was confined to the CNS at all developmental stages. These results suggest that there is at least one LRR protein family in the mouse and that these molecules may play significant but distinct roles in neural development and in the adult nervous system.

Amino Acid Sequence↗

PubMed1996

Diffuse sclerosing osteomyelitis of the mandible: its characteristics and possible relationship to synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome.

PURPOSE: This article reports on the possible relationship of diffuse sclerosing osteomyelitis (DSO) of the mandible to synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome. PATIENTS AND METHODS: The pathologic features in 12 new DSO patients and those in previously reported cases were reviewed and compared with those of SAPHO syndrome. RESULTS: Many similarities were noted between the two entities in terms of the clinical, radiographic, and histologic features. Furthermore, multiple bone lesions and skin lesions (palmoplantar pustulosis and psoriasis) were observed not only in SAPHO syndrome but also in DSO patients. CONCLUSION: DSO is concluded to be one manifestation of SAPHO syndrome.

Acne Vulgaris↗

PubMed1996

Prevention of coprophagy modifies magnesium absorption in rats fed with fructo-oligosaccharides.

We developed a new type of anal cup for prevention of coprophagy and determined whether the absorption of Ca and Mg and the stimulatory effects of feeding fructo-oligosaccharides (FO) on the absorption of Ca and Mg were altered by prevention of coprophagy in rats. Rats were fed on a FO-free diet or a diet containing 50 g FO/kg for 2 weeks with or without prevention of coprophagy. FO-feeding increased the apparent absorptive ratio of Ca and Mg in rats with or without prevention of coprophagy. However, in the FO-fed groups the absorptive ratio of Mg in rats with prevention of coprophagy was higher than in rats without prevention of coprophagy. The Ca content of the femur was higher in rats fed on the FO-diet than in rats fed on the FO-free diet both with and without coprophagy. In conclusion, FO-feeding increased the absorption of Ca and Mg in rats both with and without coprophagy. Moreover, prevention of coprophagy enhanced the absorption of Mg in rats fed with FO. Coprophagy has to be considered when the effects of luminal fermentation or mineral absorption are examined in rats.

Animals↗

PubMed1996

Unique genomic structure and expression of the mouse alpha 2,8-sialyltransferase (ST8Sia III) gene.

The mouse Sia alpha 2,3Gal beta 1, 4GalNAc alpha 2,8-sialyltransferase (ST8Sia III) genomic gene, whose transcripts are only expressed in fetal and newborn brain and testis, was isolated and its 5'-flanking region was analyzed. The gene was found to span about 8 kb and to be composed of only four exons. The genomic ST8Sia III gene is much smaller and its organization much simpler than other sialyltransferase genes so far reported, which span more than 25 kb and comprise seven or more exons. In particular, the sialyl motif L of ST8Sia III, which is a highly conserved region in all cloned sialyltransferases, was in one exon. In contrast, this motif is encoded by discrete exons in the other sialyltransferases. The ST8Sia III gene was highly expressed in the mouse brain and gave rise to at least three transcripts (2.1 kb, 2.4 kb, and 6.5 kb), which differed in the length of their 3'-untranslated regions through the alternative use of different polyadenylation sites. Primer extension and S1 nuclease protection analyses of mRNA prepared from newborn brain revealed that ST8Sia III gene expression started from a unique site at 382 nt upstream of ATG. Although the promoter region lacked an apparent TATA or CCAAT box and potential regulatory motifs, a transfection experiment involving neuroblastoma cells expressing ST8Sia III demonstrated the minimal promoter activity exhibited by the proximal region 418 bp upstream from the ATG codon, which suggests the presence of tissue-specific enhancer elements.

3T3 Cells↗

PubMed1996

Relationship between the mandibular and lumbar vertebral bone mineral density at different postmenopausal stages.

OBJECTIVE: To analyse the relationship between mandibular and general skeletal mineral status at two different postmenopausal stages. METHODS: Using dual energy quantitative computed tomography, the mandibular and 3rd lumbar (L3) vertebral bone mineral density (BMD) were evaluated in 21 women within five years after the menopause (recent postmenopause) and 23 women more than five years after (long-term postmenopause). RESULTS: There were significant correlations between the mandibular cortical and L3 vertebral BMD (p < 0.01) in the recent postmenopausal women and between the mandibular BMD and the trabecular BMD of L3 vertebrae (p < 0.05) in the long-term postmenopausal women. CONCLUSION: These results suggest that the general mineral status more markedly affects the mandibular cortex in the recent postmenopausal stage and both cortical and trabecular bone in the long-term postmenopausal stage.

Adult↗

PubMed1996

Usefulness of panoramic radiography in the diagnosis of postmenopausal osteoporosis in women. Width and morphology of inferior cortex of the mandible.

OBJECTIVES: To evaluate the usefulness of width and morphology of the inferior cortex of the mandible on panoramic radiographs in the diagnosis of postmenopausal osteoporosis. METHODS: The width and morphology of the mandibular inferior cortex on panoramic radiographs were compared with trabecular bone mineral density (TBMD) of the 3rd lumbar vertebrae (L3) measured by dual energy quantitative computed tomography in 29 premenopausal and 95 postmenopausal women. RESULTS: There was a significant negative correlation between the width (Kendall's tau = -0.36, p < 0.001) and morphology (Kendall's tau = -0.49, p < 0.001) of the mandibular inferior cortex and the L3 TBMD. Regression analysis showed that significant linear relationships were observed between the L3 TBMD and age (p < 0.001), cortical width (p < 0.05), morphology (p < 0.05), controlling body mass index, number of teeth present and menopausal status (R2 = 0.42). CONCLUSION: Our results suggest that panoramic radiography could be reliable in screening for osteoporosis.

Adult↗

PubMed1996

Case report. synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome.

A case of the SAPHO (synovitis, acne, pustulosis, hyperostosis and osteitis) syndrome in a 35-year-old woman is presented. Ignorance of this entity on the part of the physicians treating the patient may have contributed to her having repeated diagnostic procedures and treatment, some of which may have been unnecessary. Dentists are encouraged to suspect the SAPHO syndrome when they encounter a patient with mandibular osteomyelitis together with symptoms involving other bones and skin lesions such as pustulosis or psoriasis.

Acne Vulgaris↗

PubMed1996

[Measurement of bone density by ultrasound bone densitometer in normal pregnant women].

The bone mineral density in reproductive aged and pregnant women was measured with an ultrasound bone densitometer (Achilles, Luner Co, USA). Both parameters of bone density on Os calsis, sound of speed (SOS) and broad ultrasound attenuation (BUA) were significantly correlated with bone mineral density in lumbar2-4 measured by dual energy X-ray absorptiometry (DXA) (p < 0.01) in reproductive aged women (mean age; 24.5 +/- 2.3, n = 30). The changes in bone density during pregnancy and at delivery were studied. In a cross-sectional study, no significant changes in SOS, BUA and stiffness were observed, but in a longitudinal study (n = 21), all of these parameters decreased as pregnancy advanced. The markers of bone turnover (serum Ca, alkaline phosphatase, procollagen type 1-C peptide, urinary Ca/Cr and deoxypyridinoline/Cr) did not change during pregnancy. Ten pregnant women with low bone density (less than-1.5 SD mean value) were found. There was no significant difference between the markers of bone turnover in pregnant women with low and normal bone density. The clinical usefulness of the screening of bone density of reproductive aged and pregnant women to detect osteopenia is suggested.

Adult↗