Biomedical subjects

R Mori

Publications and source records attributed to R Mori.

At least 73 records · Page 4Linked to original sources

PubMed1995

Backscattered electron imaging and energy-dispersive X-ray microanalysis studies of evidence for calcium salt heterogeneity in fifteen gallstones from an elderly human.

We examined 15 variably-sized gallstones, taken from an elderly male, by backscattered electron imaging and energy-dispersive X-ray microanalysis to learn the structural and distribution patterns of gallstone calcium (Ca-) salts. Of the 13 cholesterol-rich stones, nine stones had peripheral concentric layers of Ca-carbonate, whereas 2 stones had peripheral layers of Ca-phosphate. No Ca-salts were detected from 2 cholesterol-rich stones. The 2 stones containing Ca-phosphate had no Ca-salt cores, whereas the stones containing Ca-carbonate were separated into 3 different types: two stones with a Ca-carbonate core, four stones with several Ca-bilirubinate cores of glass-like structure, and 3 stones lacking Ca-salt cores. A closer view of the Ca-salt layers, which may be occasionally coexistent with Ca-bilirubinate, mainly showed either laminate deposits or numerous globules with a few laminae. Of the 2 cholesterol-poor stones, one had dispersed particles mainly of Ca-phosphate, and the other had loosely dispersed particles with small amounts of Ca-phosphate, bilirubinate, and/or palmitate. Some relationship between the size and Ca-salt species of these gallstones was suggested. Gallstones collected from the same individual showed a considerable heterogeneity of Ca-salts.

Aged↗

PubMed1995

Energy-dispersive X-ray microanalysis of calcified tissues after NaOCl treatment and/or resin embedding.

By energy-dispersive X-ray microanalysis (EDX) in scanning electron microscopy, we studied the calcification of the inner-basic lamellas of a cow bone and the coronal cementum of a horse tooth treated with sodium hypochlorite (NaOCl). These tissues were divided into 4 groups with a combination of NaOCl treatment and polyester-resin embedding including, [A]: non-NaOCl + Resin, [B]: non-NaOCl + non-resin, [C]: NaOCl + Resin, and [D]: NaOCl + non-Resin. From the Ca and P values by EDX analysis, it was suggested that the natural porous spaces of [B] were higher than those of [A], and both the natural and NaOCl-soluble porous spaces were highest in [D]. However, [A] had the lowest porous spaces in both the tissues because the micropores formed 3-dimensionally by NaOCl treatment might be incompletely filled with the resin. The backscattered electron microscopy and the difference of the Ca/P ratios indicated that the NaOCl treatment of the calcified tissues caused some minerals besides organic materials to dissolve. Thus, the sample preparation of [B] is suitable for the quantitative EDX of calcified tissues, whereas the data of [C] except for the Ca/P ratio may be used to approximate the Ca and P contents.

Animals↗

PubMed1995

[An immunohistochemical study on microtubule associated protein-1 of normal and malignant human gastric tissue].

Microtubule Associated Protein-1 (MAP-1) plays an important role for polymerization of tublin to microtubules. Indirect immunohistochemistry using anti-MAP-1 monoclonal antibody was performed in this study. Difference of internuclear MAP-1 staining patterns between normal and malignant human gastric tissues was investigated. Normal gastric tissue had localized MAP-1 positive staining nucleus in corresponding area of generative cell zone of gastric gland. On the other hand, the 75% cases of gastric cancer showed numerous labeled nuclei in most of the cancer tissues, and 25% cases did not show positive staining of nuclei in cancer tissue. The nuclei staining were classified as negative (-), weak granular (+) and strong punctate (++). The tissue staining pattern was fallen into two patterns, uniform and ununiform stained groups. Positive nuclei staining for MAP-1 and staining pattern had no correlation with histological type of gastric cancer, vessel invasion and lymph node metastasis. But post operative 5-years survival rares were 77.3% in uniform stained group and 30.0% in ununiform stained group. Thus, there were relationship between the post operative survival ratio and the staining pattern of nuclei. Internuclear MAP-1 staining pattern was considered to be one of effective parameters on prognostic sign in gastric cancer.

Antibodies, Monoclonal↗

PubMed1995

The structural patterns and mineralization values of prismless enamel, a case of mild enamel hypoplasia.

In examining the prismless enamel (PL) distribution from the inner to surface layers of a human incisor with hypoplastic perikymatas with enamel pits, we determined the structural patterns and mineralization values by microradiographic, optical, and scanning electron microscopic observations. The PL containing abnormal prisms ranged from 20 to 250 micrometers in thickness. The alternated layers of the PL and prismatic enamel, in parallel with the Retzius lines, showed a roughly zigzag pattern based on the main orientation of enamel crystals. Such a pattern suggests an alternation of the disappearance and reappearance of Tomes' processes, which may have strong restorative and reactive capacities. In the mineralization values determined by microradiography, the PL was higher in the well-marked lines of Retzius, while the PL under the hypoplastic enamel pit and an area within the thick PL showed hypomineralization. The backscattered electron images indicated that the fine laminate striations and abnormal prismatic rows within the PL were hypomineralized, and the PL in the inner enamel showed a lower mineralization than the adjacent prismatic layer. Thus, the disappearance of Tomes' processes, which form prismless structures, may be unrelated to changing the mineral amount in amelogenesis.

Ameloblasts↗

PubMed1994

Positive and negative regulation of retinoid X receptor gene expression by thyroid hormone in the rat. Transcriptional and post-transcriptional controls by thyroid hormone.

The 9-cis-retinoic acid receptors (RXRs), belonging to the members of the steroid/thyroid hormone receptor superfamily, act as auxiliary proteins, heterodimerizing with other nuclear receptors such as retinoic acid receptors (RARs), vitamin D receptor, thyroid hormone receptors, and peroxisome-proliferator activated receptor, thereby transactivating target genes in a ligand-dependent manner. We have previously reported that in the rat, thyroid hormone (TH) positively and negatively regulates the hepatic mRNA levels of RXR beta and RXR gamma, respectively. In the present study, we have tried to elucidate the level at which TH regulates the gene expression of RXR beta and RXR gamma in the rat. A RNA synthesis inhibitor (actinomycin D), but not a protein synthesis inhibitor (cycloheximide), blocked the induction of RXR beta mRNA by TH. On the other hand, none of these drugs inhibited the decrease of RXR gamma mRNA levels caused by TH. Nuclear run-on assays showed that the transcription rate of the RXR beta gene was positively regulated by TH, whereas the transcription of RXR gamma gene was not controlled by TH. Taken together, these results indicate that the gene expression of RXR beta is positively regulated by TH at transcriptional level, while the negative regulation of the RXR gamma gene expression by TH may occur at a post-transcriptional level in intact rat. Thus, the RXR-mediated signal transductions may be modulated in part through TH control of the levels of RXR beta and RXR gamma.

Animals↗

PubMed1994

High-affinity specific [3H]tamsulosin binding to alpha 1-adrenoceptors in human prostates with benign prostatic hypertrophy.

The binding of a novel radioligand, [3H]tamsulosin, to human prostatic membranes with benign prostatic hypertrophy (BPH) has been characterized. [3H]Tamsulosin rapidly associated with its binding sites in human prostatic membranes with BPH, and the binding reached steady state by 30 min at 25 degrees C. The rate constants for association and dissociation of [3H]tamsulosin binding were calculated to be 0.21 +/- 0.05/nM per minute and 0.01 +/- 0.004/min, respectively. The specific binding of [3H]tamsulosin in human prostatic membranes was saturable and of high affinity (Kd = 0.04 +/- 0.01 nM). The density of [3H]tamsulosin-binding sites (Bmax) was 409 +/- 28 fmol/mg protein. The Kd and Bmax values for [3H]tamsulosin binding in human prostates were significantly lower than those for [3H]prazosin binding. [3H]tamsulosin binding was remarkable for its significantly lower degree of nonspecific binding. Six alpha-adrenoceptor antagonists competed with [3H]tamsulosin for the binding sites in the rank order: tamsulosin > WB4101 > prazosin > S-(+)-isomer > naftopidil > yohimbine. The binding affinities (pKi) of these antagonists for [3H]tamsulosin binding in human prostates closely correlated with their pharmacological potencies (pA2) in prostates. In conclusion, [3H]tamsulosin selectively labels alpha 1-adrenoceptors in human prostates, and thus may become a useful radioligand for the further analysis of these receptors.

Adrenergic alpha-Antagonists↗

PubMed1994

Detection of active cytomegalovirus infection in inflammatory aortic aneurysms with RNA polymerase chain reaction.

PURPOSE: We previously reported the possible role of human cytomegalovirus in the pathogenesis of inflammatory aortic diseases. To further analyze the viral cause of human aortic diseases, in this study we examined the presence and the replication of human Herpesviridae in 60 aortic tissues, including 7 inflammatory aneurysms, 37 atherosclerotic aneurysms, and 16 normal aortas. METHODS: To detect the genome of herpes simplex virus (type 1, type 2), cytomegalovirus, and Epstein-Barr virus, DNA polymerase chain reaction for each virus was performed. To analyze these herpesviral replications, the viral transcript was detected with RNA polymerase chain reaction. RESULTS: The DNA polymerase chain reaction showed that either herpes simplex virus or cytomegalovirus was present more frequently in inflammatory (29% or 86%, respectively) and atherosclerotic aneurysms (27% or 65%, respectively) than in normal aortic tissues (6% or 31%, respectively), whereas the Epstein-Barr viral genome was not detected in any aortic tissue specimens. By the use of RNA polymerase chain reaction, only the cytomegaloviral transcript was recognized in 71% of the inflammatory aneurysms but was not recognized in any other tissue specimens. No other herpesviral transcripts were detected in any tissue specimens examined in this study. CONCLUSIONS: Our results thus suggest that the human herpesviruses may play various roles in the pathogenicity of aortic diseases, in particular the replicating infections of the cytomegalovirus might potentially cause the formation of inflammatory aneurysms.

Aortic Aneurysm↗

PubMed1994

Physiological characteristics of inferior vena cava pulse waveform during foetal development.

Non-invasive measurements of pulsatile diameter changes (pulse waveform) in the foetal inferior vena cava (IVC) during foetal development using an ultrasonic phase-locked echo tracking system with high sampling frequency (3000 Hz) are described. Successful human foetal IVC pulse waveform recording was achieved cross-sectionally in 56 out of 68 (82%) women at 20-23, 24-27, 28-31, 32-35, and 36-39 weeks' gestation. The pulse waveform in the foetal IVC consisted of four waves (A, X, V, and Y waves). An increase in the depth of the X and Y descents was observed during the second trimester. It was considered that this was due to the decrease in placental resistance. A slightly decreased foetal heart rate during the third trimester affected the time for right ventricular diastolic filling. Our findings indicate that the alterations in resistance to right ventricular afterload produced by growth in the placenta and right atrioventricular filling patterns with advancing gestational age are reflected in the foetal IVC pulse waveform. In addition, foetal systemic and placental vascular resistance profoundly influence right atrioventricular filling patterns. It is possible to record the foetal IVC pulse waveform simply, using a quite different ultrasound methodology (phase-locked echo tracking) from that used for normal pulse echo or Doppler measurements. Such studies provide important physiological information about the normal foetus.

Adult↗

PubMed1994

Analysis by RNA-PCR of latency and reactivation of herpes simplex virus in multiple neuronal tissues.

Following intracameral inoculation with herpes simplex virus type 1 (HSV-1), BALB/c mice develop acute necrotizing chorioretinitis and infectious virus is detected in the eyes, trigeminal ganglia, brain, spinal cord and adrenal glands during acute infection. In this study, we analysed the latent phase of this experimental animal system. In mice which survived the acute infection, latent HSV-1 was recovered from the trigeminal ganglia, brain and adrenal glands by co-cultivation with Vero cells. In these tissues, both the unspliced latency-associated transcript (LAT) and the spliced LAT were detected by RNA-PCR. Following in vivo administration of cyclophosphamide and dexamethasone to induce viral reactivation, ICP0 mRNA became detectable in the multiple neural tissues, and the spliced LAT disappeared whereas the unspliced LAT remained detectable by RNA-PCR. Sequence analysis of the RNA-PCR products revealed that the GC-AG splicing signal previously reported for LATs from trigeminal ganglia was also detected in LATs from the brain and adrenal glands, suggesting that the splicing of LATs might be associated with the maintenance of and/or reactivation from latency. The generalized latent infection of HSV-1 described in this study might serve as an experimental model of possible viral reactivation from organs that do not innervate the primary port of entry.

Adrenal Glands↗

PubMed1994

Detection of herpes simplex virus type 1-encoded RNA by polymerase chain reaction: different pattern of viral RNA detection in latently infected murine trigeminal ganglia following in vitro or in vivo reactivation.

Herpes simplex virus type 1 (HSV-1) establishes latent infection in the sensory ganglia. To investigate the process of reactivation from latency, we used the RNA polymerase chain reaction (RNA-PCR) to detect the expression of several HSV genes. BALB/c mice were inoculated in the anterior ocular chamber with HSV-1 strain KOS and the trigeminal ganglia were examined at least 8 weeks after inoculation. Latency-associated transcripts (LATs) were found in the latently infected ganglia and remained detectable 120 h after explantation. Besides LATs, we detected transcripts for infected cell protein 0 (ICP0) (Vmw110) 24 h after explantation, but RNAs encoding ICP4 (Vmw175), ICP27, thymidine kinase and VP16 (ICP25; Vmw65) remained undetectable for 120 h after explantation. Following in vivo reactivation of HSV-1 by administration of cyclophosphamide and dexamethasone, all viral transcripts including ICP0 RNA became detectable. The RNA-PCR enabled us to detect ICP0 RNA much earlier than has been previously reported in studies using the Northern blot technique and has laid a foundation for further study of viral and cellular transcripts during reactivation. Our results suggest that the process of reactivation of HSV-1 from trigeminal ganglia may be divided into at least two steps: (i) initiation of ICP0 gene transcription and (ii) detectable transcription of the other genes. The second step may be regulated in part by the host immune system, since cyclophosphamide and dexamethasone administration enabled the detection of several viral transcripts.

Animals↗

PubMed1994

Comparative study on alpha 1-adrenoceptor antagonist binding in human prostate and aorta.

1. Specific binding of [3H]-prazosin in prostatic and aortic membranes of humans was saturable and of high affinity (prostate: apparent dissociation constant, Kd = 0.35 +/- 0.03 nmol/L; aorta: Kd = 0.26 +/- 0.03 nmol/L). The density of [3H]-prazosin binding sites (Bmax) for prostate and aorta was 546 +/- 31 and 61.6 +/- 1.6 fmol/mg protein, respectively. 2. Prazosin, YM617, naftopidil and urapidil competed with [3H]-prazosin for the binding sites in a dose-dependent manner in the prostate and aorta of humans. The binding affinities of these antagonists in both tissues were compared, based on the inhibition constant, Ki. Both prazosin and urapidil showed similar affinity to [3H]-prazosin binding sites in human tissue, whereas YM617 and naftopidil showed approximately a 12 and two times higher affinity, respectively, to alpha 1-adrenoceptor sites of prostate than aorta. 3. The chloroethylclonidine treatment reduced partially the Bmax values for specific [3H]-prazosin binding in the prostate and aorta of humans with little effect on the Kd values. 4. These data suggest that YM617 is a relatively selective antagonist of human prostatic alpha 1-adrenoceptors.

Adrenergic alpha-Antagonists↗

PubMed1994

[Detection of cytomegalovirus (CMV) antigen for rapid diagnosis and monitoring of CMV diseases in AIDS].

Ten to forty percent of the patients with acquired immunodeficiency syndrome (AIDS) develop sight- or life-threatening cytomegalovirus (CMV) infections. In some patients with AIDS, CMV is detected in the bronchoalveolar lavage fluid (BALF), urine, and other specimens, even when there are no symptoms of CMV disease. An indicator of active CMV infection is needed to facilitate the diagnosis of CMV disease in patients with AIDS or HIV infection and the evaluation of the efficacy of subsequent treatment. The present study was conducted during the period from 1993 to 1994. The subjects consisted of three patients with AIDS and a confirmed diagnosis of CMV disease (one case of retinitis, one case of gastrointestinal disease and one case of pneumonia), and five HIV-positive patients in whom CMV associated disease was ruled out. Those patients were monitored occasionally for the following parameters of active CMV infection and disease: expression of CMV antigen in the nucleus of polymorphonuclear leukocyte (CMV antigenemia), as it was determined with a monoclonal antibody against a lower matrix protein (p65); infectious CMV detected by shell vial method; CMV DNA detected by PCR; anti-CMV antibody titer; and histological findings. CMV p65 antigen was detected in the leukocytes of both the peripheral blood and BALF during the early phase of CMV disease in three out of three cases of the CMV disease group, and this antigen became negative in two out of two cases who responded to the therapy. All the five patients in the CMV-related-disease-negative group were negative for CMV antigenemia.(ABSTRACT TRUNCATED AT 250 WORDS)

AIDS-Related Opportunistic Infections↗

PubMed1994

Serum coenzyme Q10 in uremic patients on chronic hemodialysis.

In a group of 48 chronic hemodialysis patients, serum levels of coenzyme Q10 (CoQ) have been measured and appeared abnormally low in 62% of cases. Figures were positively correlated to those of serum vitamin E (vit E), although the latter were within a normal range. The chronic hemodialysis (CHD) patients with normal serum values of CoQ exhibited higher blood triglycerides. Pathologically low levels of serum vit E were found only in uremic subjects on conservative regimen with dietary restrictions and low compliance to protein-caloric intake. The reduced CoQ levels may contribute to the defective serum antioxidant activity and the increased peroxidative damage in uremic patients on CHD.

Aged↗

PubMed1994

Necrotizing retinitis in severe combined immunodeficiency mice following intracameral inoculation of herpes simplex virus type 1.

Necrotizing retinitis in severe combined immunodeficiency (SCID) mice following intracameral inoculation of herpes simplex virus type 1 provided an experimental model for acute retinal necrosis in AIDS and other immunocompromised patients. In order to assess the involvement of the immunological response in the pathogenesis, adoptive transfer experiments were conducted. Without transfer, SCID mice developed predominantly unilateral necrotizing retinitis and died within 10 days. Transfer of immune serum lengthened the survival time but resulted in bilateral necrotizing retinitis. Two of 5 mice transferred with CD4+ T cells and none of 7 transferred with CD8+ T cells developed bilateral necrotizing retinitis. Our results indicate that ipsilateral retinal necrosis occurs with or without a specific immunological response, and that antibodies and/or CD4+ T cells accelerate the contralateral retinal necrosis.

Animals↗

PubMed1994

Stromal keratitis induced by a unique clinical isolate of herpes simplex virus type 1.

Glycoprotein C (gC)-negative clinical isolates of herpes simplex virus type 1 (HSV-1) are very rare. An HSV-1 strain (TN-1), isolated from a patient with herpetic keratitis, exhibited a gC-negative phenotype. While a gC-negative mutant showed reduced pathogenicity and failed to induce herpetic stromal keratitis (HSK) in a previously reported mouse model, TN-1 induced HSK in mice comparable to RTN-1-20-3, a gC-positive recombinant virus derived from TN-1. Virus growth in eyes and brains and the mortality of TN-1-inoculated mice were equal to or higher than those of RTN-1-20-3-inoculated mice.

Animals↗

PubMed1994

Scanning electron microscopy and electron probe microanalysis studies of human pineal concretions.

The calcareous concretions of human pineal bodies were investigated with scanning electron microscopy and electron probe microanalysis. The initial concretions measuring 5-7 microns in diameter may have started at the calcified pinealocytes. They grew appositionally forming concentric laminations, and then the simple calcospherulites over 20 microns occasionally aggregated with each other. Some of them became numerous spherulite-aggregated concretions. Others individually grew with scallop-shaped concentric laminations at intervals of 0.05-1 microns and became lobated calcospherulites up to 0.5 mm. The concretions over 0.5 mm were formed by their attachments. The major elements were Ca and P, while traces of S, Mg, and Na were detected. In the calcification and crystallization values, the center of the concretions over 50 microns was significantly higher than the periphery, while there were no differences among the centers and also among the peripheries. The Ca and P amounts in the center were 30.8% and 14.2% by weight and the Ca/P molar ratio was 1.68; thereby the sand-grain-shaped crystals may be nearly hydroxyapatite, as reported previously.

Aged↗

PubMed1993

Tumor progression in hepatocellular carcinoma may be mediated by p53 mutation.

Human hepatocellular carcinoma (HCC) often contains intratumoral subpopulations of heterogeneous cellular differentiations within each tumor. To analyze the genetic alterations of p53 in the heterogeneous subpopulations, we examined 68 intratumoral nodular lesions within 34 HCCs composed of two distinct subpopulations. The cellular differentiations were determined histologically by Edmondson's grading system. Nine (26.5%) of 34 HCCs examined were found to have genetic alterations in exons 5 to 8 of the p53 gene, resulting in amino acid substitutions. Three of these nine HCCs with p53 mutations showed genetic heterogeneity of the p53 gene within each tumor; one HCC had a single missense mutation at codon 210 (asparginine to 210-serine) in an intratumoral lesion of Edmondson Grade II and double missense mutations at codons 210 and 217 (asparginine to 210-serine and valine to 217-alanine) in another intratumoral lesion of Edmondson Grade III. The remaining two HCCs had p53 mutations only in lesions of a higher grade. In total, the p53 mutations were detected in none of eight Edmondson Grade I lesions, in five of 29 Grade III lesions (17.2%), in eight of 26 Grade III lesions (30.8%), and in three of five Grade IV lesions (60.0%). Thus, our data revealed that the p53 mutations were closely related to the progression of HCC and that, in certain cases, malignant cells which acquired the p53 mutations might develop into dedifferentiated subpopulations within individual HCC.

Amino Acid Sequence↗

PubMed1993

Sequential observations followed by acid etching on the enamel surfaces of human teeth under scanning electron microscopy at low vacuum.

A scanning electron microscope equipped with a low vacuum specimen chamber and a Robinson's backscattered electron detector was employed to observe the natural surfaces of human buccal enamel before and after 30 percent phosphoric acid etching sequentially up to 90 sec at the same sites with no coatings. Furthermore, successive etching patterns were compared between deciduous and permanent teeth. On the imbrication lines of young permanent teeth, prism-end pits surrounded with a "prismless" structure occasionally disappeared after acid etching and became a prismless enamel. Sequential etching caused the prismless areas and the areas of a type 1 etching pattern to decrease, and a cone-shaped prism structure and a complex type of the type 1 and type 2 etching pattern (type 1-2) to appear. The former was a transitional type between the prismless enamel and type 2 prisms. These etched surfaces show type 2 prisms after deeper etching. Small dome-shaped structures, slightly elevated on the attrited enamel surfaces, were found only in deciduous teeth. After acid etching, such areas which retained the prismless enamel rose to the underlying surfaces of cone-shaped prisms.

Acid Etching, Dental↗