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Biomedical subjects

M Yamaguchi

Publications and source records attributed to M Yamaguchi.

At least 181 records · Page 10Linked to original sources
PubMed2001

Changes in quantitative profile of extracellular matrix components in the kidneys of rats with adriamycin-induced nephropathy.

Extracellular matrix components (ECMs) in histological sections of the kidney cortex from the rats with adriamycin (ADR)-induced nephropathy (5 mg/kg, i.v.) were quantified by an immunohistochemical micromethod. Changes in kidney histopathology and urine and blood biochemistry were investigated. Enlarged kidneys were granular on the surface and pale in color in ADR-treated rats, and these rats had kidneys with glomeruli with expanded mesangial area and with capillary aneurysm. Severe albuminuria, hypoalbuminemia, hypercholesterolemia and disorders in other nephrotic parameters were observed in ADR-treated rats. Type I and IV collagens, fibronectin and laminin contents in the renal cortex of ADR-treated rats at 10 weeks were 329, 317, 263 and 295%, respectively, higher than in each vehicle control, and those at 28 weeks were 1,211, 930, 1,057 and 1,012%, respectively. The glomerular sclerotic abnormalities progressed in a time-dependent manner. Moreover, there was a strong correlation between the ECM levels and serum creatinine and blood urea nitrogen levels. In conclusion, microquantification provided useful information for accurate diagnosis and prognosis of nephrotic lesions and is a good tool to assess the advancement of renal disorders in patients with nephropathy.

Albuminuria↗
PubMed2001

Isolation of Encephalitozoon cuniculi using primary tissue culture techniques from a rabbit in a colony showing encephalitozoonosis.

Encephalitozoon spores were isolated in a primary tissue culture of the kidneys from an encephalitozoonosis-suspected rabbit in a municipal zoo in Hokkaido. The isolated spores were morphologically characteristic of microsporidial ones in chromotrope stain, and proven to be E. cuniculi by a polymerase chain reaction (PCR) with a species-specific primer set and by direct DNA sequencing of the PCR products.

Animals↗
PubMed2001

Localization of proliferative and apoptotic cells in the kidneys of ICR-derived glomerulonephritis (ICGN) mice.

The ICR-derived glomerulonephritis (ICGN) mouse is a novel inbred mouse strain with a hereditary nephrotic syndrome, considered to be a good model of human idiopathic nephrotic syndrome and develops proteinuria, hypoproteinemia and anemia. In the present study, we compared the cell kinetics in the kidneys of ICGN mice with age-matched ICR mice as normal controls. The proliferating cells were visualized by 5-bromo-2'-deoxyuridine labeling, and apoptotic cells were determined by terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end-labeling. Many proliferating epithelial cells of renal tubules, glomerular mesangial cells and tublointerstitial fibroblast-like cells were observed in the kidneys of ICGN mice, but no proliferating cells were seen in the kidneys of ICR mice. Apoptotic cells had round nuclei, and were observed only in the tubulointerstitium in the kidneys of ICGN mice but not in that of controls. The proliferation of renal tubular epithelial cells may represent a compensatory response, and that of mesangial and fibroblast-like cells may play a pathogenic role in nephrotic syndrome. Apoptosis in tubulointerstitial cells with round nuclei may have been erythropoietin-producing cells, and probably caused anemia.

Animals↗
PubMed2001

Expression of prolactin-releasing peptide in human placenta and decidua.

The aims of this study were to determine whether the human placenta and decidua express PRL-releasing peptide (PrRP) mRNA and whether PrRP regulates PRL secretion from cultured human decidual cells. PrRP gene expression was analyzed by reverse transcription (RT)-PCR, and the level of the gene expression was quantified by a ribonuclease protection assay. PrRP gene expression was detected in both the placenta and decidua. These tissues expressed PrRP mRNA throughout pregnancy and the level of PrRP mRNA expression somewhat increased during midpregnancy. Placental and decidual cells also expressed PrRP mRNA, in vitro. To determine whether PrRP affects decidual PRL secretion, human endometrial stromal cells and decidual cells were cultured and treated with or without 1 microM PrRP31. PrRP31 did not affect PRL secretion in either short or long term incubation. Moreover, the RT-PCR analysis indicated that human decidua does not express the PrRP receptor, hGR3, mRNA. These findings suggest that PrRP produced by the human placenta and decidua does not affect decidual PRL secretion due to a lack of the receptor, and that it may play other roles during pregnancy.

Cells, Cultured↗
PubMed2001

6-O-sulfo de-N-acetylsialyl Lewis X as a novel high-affinity ligand for human L-selectin: total synthesis and structural characterization.

Total synthesis and structural characterization of a novel 6-O-sulfo de-N-acetylsialyl Lewis X, which was originally discovered as a minor by-product of the parent 6-O-sulfo N-acetylsialyl Lewis X, a high-affinity endogenous ligand for human L-selectin, are described. The total synthesis has been achieved by a highly efficient, regio- and alpha-stereoselective glycosylation of N-trifluoroacetylneuraminic acid, selective protections of the 3- and 6-hydroxyl groups of N-acetylglucosamine that undergo fucosylation and sulfation, and construction of the glycolipid structure containing a ceramide. The structure of 6-O-sulfo de-N-acetylsialyl Lewis X ganglioside was characterized by fast atom bombardment mass spectrometry (FAB-MS).

Carbohydrate Sequence↗
PubMed2001

Liquid chromatographic determination of ornithine and lysine based on intramolecular excimer-forming fluorescence derivatization.

A highly sensitive and selective fluorometric determination method for ornithine and lysine has been developed. This method is based on an intramolecular excimer-forming fluorescence derivatization with a pyrene reagent, 4-(1-pyrene)butyric acid N-hydroxysuccinimide ester (PSE), followed by reversed-phase liquid chromatography (LC). The analytes, containing two amino moieties in a molecule, were converted to the corresponding dipyrene-labeled derivatives by reaction with PSE. The derivatives afforded intramolecular excimer fluorescence (450-550 nm) which can clearly be discriminated from the normal fluorescence (370-420 nm) emitted from PSE and monopyrene-labeled derivatives of monoamines. The structures of the derivatives and the emission of excimer fluorescence were confirmed by LC with mass spectrometry and with three-dimensional fluorescence detection system, respectively. The PSE derivatives of ornithine and lysine could be separated by reversed-phase LC on ODS column with isocratic elution. The detection limits (signal-to-noise ratio = 3) for ornithine and lysine were 3.5 and 3.7 fmol, respectively, for a 20-microl injection. Furthermore, this method had enough selectivity and sensitivity for the determination of ornithine and lysine in normal human urine.

Calibration↗
PubMed2001

Complications during clinical courses of Pneumocystis carinii pneumonia in patients with acquired immunodeficiency syndrome.

OBJECTIVE: To describe the incidence of complications before and during therapy of Pneumocystis carinii pneumonia (PCP) in patients with acquired immunodeficiency syndrome (AIDS). METHODS: A retrospective review of the patient's medical records. PATIENTS: A total of 29 patients with AIDS and PCP who were admitted to the AIDS Clinical Center, International Medical Center of Japan from July 1996 to November 1999. RESULTS: Adverse effects were found in 24 (88.9%) of 27 patients treated with trimethoprim/sulfamethoxazole (T/S), 6 (46.1%) of 13 treated with parenteral pentamidine, and 2 (20%) of 10 treated with inhaled pentamidine. Infectious and/or non-infectious complications were found in 25 (86.2%) of 29 study patients. Regarding infectious complications, 16 (55.2%) were found on admission and 10 cases (34.5%) with infectious complications were identified during admission; including oral candidiasis (37.9% and 17.2%, respectively) and genital herpes (3.4% and 6.9%, respectively). Cytomegalovirus antigenemia was detected in 4 cases (13.8%) on admission and 12 cases (41.4%) during admission. Non-infectious complications affected 11 cases (37.9%) on admission, and 6 cases (20.7%) during admission, the latter included heart failure (10.3%) and pneumothorax (6.9%). PCP was successfully treated in all but one patient who suffered from repeated pneumothorax. CONCLUSION: Treatment of PCP can be problematic and it is important to be aware of the high incidence of various complications that can occur during the treatment of PCP.

AIDS-Related Opportunistic Infections↗
PubMed2001

Two cases of long lasting bacteremia due to Mycobacterium avium complex despite new macrolides-containing regimens in patients with acquired immunodeficiency syndrome.

The prognosis of Mycobacterium avium complex (MAC) infection has been improved by new macrolides-containing regimens and the use of highly active antiretroviral therapy (HAART) in the treatment of acquired immunodeficiency syndrome (AIDS). We report on two AIDS cases with long lasting bacteremia due to MAC under this regimen. Both patients experienced problems due to side effects from the anti-MAC regimen and from an immune-reconstitution syndrome related to HAART. MAC infection persisted despite treatment, however, no anti-MAC drug-resistant isolates emerged throughout the clinical course in either case. These cases demonstrate that therapy for disseminated MAC infection is sometimes difficult even with HAART and macrolides-containing regimens.

Acquired Immunodeficiency Syndrome↗
PubMed2001

Enhancement of plasminogen activator activity stimulated by LPS in gingival fibroblasts of individuals with Down syndrome.

Individuals with Down syndrome (DS) have a high prevalence of periodontal disease, which develops early and progressed rapidly and extensively, in comparison with healthy controls. The severe periodontal disease in individuals with DS has been considered to result from abnormal factors in their host responses. The mechanisms involved in the periodontal inflammatory processes in individuals with DS are not fully understood. Plasminogen activators (PA) are serine proteases that are well known for their part in the initiation of the fibrinolytic cascade leading to the generation of plasmin in periodontal homeostasis, including fibrinolysis and connective tissue remodeling. The PA-plasmin system affects the progression of periodontal disease. In the present study, we examined the effects of the levels of PA activity stimulated with lipopolysaccharide (LPS) in the gingival fibroblasts from donors with DS (DGF). The levels of PA activity without LPS were low in the DGFs, the same as that in the gingival fibroblasts from donors of healthy controls (NDGF). In contrast, the levels of PA activity with LPS in DGFs were significantly higher than that in the NDGFs. These results suggested that PA plays an important role in inducing extensive and rapid inflammation in the periodontal disease in individuals with DS.

Adolescent↗
PubMed2001

Stimulatory effect of zinc and growth factor on bone protein component in newborn rats: enhancement with zinc and insulin-like growth factor-I.

The effect of zinc and growth factor on bone protein component in newborn rats was investigated. The characterization of protein component in the femoral-diaphyseal and metaphyseal tissue of newborn rats (3-35 days old) was examined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The diaphyseal and metaphyseal tissues of 7 days-old rats were cultured for 24 or 48 h in a medium containing either vehicle, zinc sulfate (10-4 M) or dipicolinate (10-3 M), a chelator of zinc ion, in the presence or absence of insulin-like growth factor-I (IGF-I; 10-8 M) or transforming growth factor-beta (TFG-beta; 10-10 M) with an effective concentration. Many cellular protein molecules were present in the diaphyseal and metaphyseal tissues; potent bands were seen in protein molecules with about 66 and 46 kDa. Protein molecule of about 66 kDa was greatly released in the medium cultured with the diaphyseal and metaphyseal tissues. This protein in the medium was increased by culture with zinc, IGF-I or TGF-beta. Total protein content in the medium cultured with the diaphyseal and metaphyseal tissues was significantly increased in the presence of zinc, IGF-I or TGF-beta. The IGF-I-increased medium protein content was significantly enhanced by zinc. This enhancing effect was not seen in TGF-beta. Alkaline phosphatase activity and deoxyribonucleic acid (DNA) content in the diaphyseal and metaphyseal tissues was significantly increased by culture with zinc, IGF-I or TGF-beta. The effect of IGF-I was significantly enhanced by zinc, while it was not found in TGF-beta. The effect of IGF-I or TGF-beta in increasing the bone components was seen in the presence of dipicolinate. This study demonstrates that zinc, like IGF-I and TGF-beta, can increase protein components in the femoral-diaphyseal and metaphyseal tissues of new-born rats. Zinc may especially play a role in bone growth in collaboration with IGF-I.

Alkaline Phosphatase↗
PubMed2001

Decrease in Ca2+-ATPase activity in the brain plasma membrane of rats with increasing age: involvement of brain calcium accumulation.

The alteration in Ca(2+)-ATPase activity in the brain plasma membrane of rats with increasing age was investigated. Calcium content in the brain tissues was significantly raised in aged rats (50 weeks old) as compared with that of young rats (5 weeks old). Increasing age caused a significant decrease in Ca(2+)-ATPase activity in the brain plasma membranes. The presence of N-ethylmaleimide (2.5 or 5 mM), a modifying reagent of thiol (SH)-groups, in the reaction mixture caused a significant decrease in the brain plasma membrane Ca(2+)-ATPase activity of young and aged rats, while dithiothreitol (2.5 or 5 mM), a protecting reagent of SH-groups, produced a significant increase in the enzyme activity, indicating that the SH-group is an active site of Ca(2+)-ATPase. The active site of Ca(2+)-ATPase may not be impaired by ageing. The brain plasma membrane Ca(2+)-ATPase activity of young rats was significantly reduced in the presence of dibutyryl cyclic AMP (10(-7)-10(-5) M) or inositol 1, 4, 5-trisphosphate (10(-7)-10(-5) M) in the reaction mixture. Such an decrease was not seen in aged rats. The responsibility for signaling factors seemed to be weakened by ageing. Calmodulin (2.5 and 5 microg/ml) or regucalcin (10(-8) and 10(-7) M), a Ca(2+)-regulating protein, did not have an effect on Ca(2+)-ATPase activity. This study demonstrates that ageing induces a decrease in Ca(2+)-ATPase activity in the brain plasma membranes. This finding suggests a cellular mechanism by which ageing causes calcium accumulation in brain.

Aging↗
PubMed2001

Increase in bone growth factors with healing rat fractures: the enhancing effect of zinc.

The effect of zinc, a stimulator of bone formation, on bone protein components in the femoral-diaphyseal tissues with fracture healing was investigated. Rats were sacrificed between 1 and 7 days after the femoral fracture, and the diaphyseal tissues were cultured in a serum-free Dulbecco's modified Eagle's medium for 24 h. Protein content in the femoral-diaphyseal tissues was markedly elevated by fracture healing. The amount of protein in the medium cultured with the diaphyseal tissues obtained from fracture healing rats was markedly elevated as compared with that of normal rats, indicating that bone protein components were secreted into culture medium. Analysis with sodium dodecyl sulfate-polyacrylamide gel elecrophoresis (SDS-PAGE) showed that many protein molecules were secreted from the diaphyseal tissues with fracture healing. Especially, protein molecule of about 66 kDa was markedly secreted by fracture healing. The presence of zinc acexamate (10(-5) and 10(-4) M) in culture medium induced a significant elevation of medium protein content; the zinc effect was enhanced by culture with the diaphyseal tissues of fracture healing rats. Also, the culture of diaphyseal tissues with fracture healing caused a significant increase in insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 (TGF-beta1) in culture medium. The production of IGF-I and TGF-beta1 from bone tissues with fracture healing was significantly enhanced in the presence of zinc acexamate (10(-6)-10(-4) M). Moreover, the addition of IGF-I (10(-8) M) or TGF-beta1 (10(-10) M) in a culture medium caused a significant elevation of protein content in the medium cultured with the femoral-diaphyseal tissues from normal and fracture healing rats. The effect of IGF-I or TGF-beta1 was significantly enhanced in the presence of zinc acexamate (10(-4) M). Also, deoxyribonucleic acid (DNA) content in the diaphyseal tissues from normal and fracture healing rats was significantly raised by the culture with IGF-I or TGF-beta1. The effect of IGF-I was significantly enhanced by zinc. The present study demonstrates that fracture healing increases production of bone IGF-I and TGF-beta1, and that this elevation is enhanced by zinc treatment.

Aminocaproates↗
PubMed2001

Molecular cloning and sequencing of the cDNA coding for a novel regucalcin gene promoter region-related protein in rat, mouse and human liver.

The molecular cloning and sequencing of the cDNA coding for a novel regucalcin gene promoter region-related protein (RGPR) was investigated using rat, mouse and human liver cDNA library with a yeast one-hybrid system and a rapid amplification of cDNA ends (RACE) method. The clone coding an unknown protein was isolated, and a novel protein was identified. This protein was termed as RGPR-p117. RGPR-p117 in rat, mouse and human liver consisted of 1058, 1051 and 1060 amino acid residues with calculated molecular mass of 117, 115 and 117 kDa and estimated pI of 5.69, 5.70 and 5.71, respectively. The homologies of amino acids among rat, mouse and human RGPR-p117 were at least 70%. RGPR-p117 had a leucine zipper motif. The expression of RGPR-p117 mRNA was found in the liver, kidney, heart, spleen, and brain of rats. The database search of the human RGPR-p117 showed that its gene consisted of at least 26 exons spanning approximately 4.1 kbp and localized on human chromosome 1q25.2. Furthermore, we found a cDNA clone which was highly identical to a front half part of the human RGPR-p117 cDNA, using the BLAST search of human RGPR-p117. This cDNA clone was a splicing variant of human RGPR-p117, which derived from human placental choriocarcinoma. Our study demonstrates that a novel gene coding RGPR-p117 is present in rat, mouse and human.

Amino Acid Sequence↗
PubMed2001

Stimulatory effect of zinc on insulin-like growth factor-I and transforming growth factor-beta1 production with bone growth of newborn rats.

The effect of zinc, an essential trace element, on insulin-like growth factor-I (IGF-I) and transforming growth factor-beta1 production was investigated to determine the role of this metal in bone growth of newborn rats. Femoral-diaphyseal and metaphyseal tissues were obtained between 1 and 28 days after birth of newborn rats, and cultured for 24 h in a serum-free Dulbecco's modified Eagle's medium containing either vehicle or zinc sulfate (10(-6) - 10(-4) M). Protein concentration in the medium was significantly increased by culture with bone tissues of newborn rats with increasing age (14 and 21 days). Medium IGF-I and TGF-beta1 concentration was gradually reduced with increasing age after birth. The presence of zinc (10(-5) and 10(-4) M) caused a significant increase in protein, IGF-I, and TGF-beta1 concentrations in the medium cultured with the diaphyseal or metaphyseal tissues obtained at 7 and 14 days after birth. The expression of IGF-I and TGF-beta1 mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR) analysis in the diaphyseal and metaphyseal tissues cultured for 24 h using rat IGF-I or TGF-beta1-specific primers. These expressions were significantly raised in the presence of zinc (10(-4) M) in culture medium. The present study demonstrates that zinc has a stimulatory effect on IGF-I and TGF-beta1 production in the femoral tissues with bone growth of newborn rats.

Animals↗
PubMed2001

[Hydrothorax during diagnostic laparoscopy].

An 83-yr-old, 44-kg woman with a 2-month history of abdominal distension received diagnostic laparoscopy. Except for chronic treated hypertension, she was healthy. The preoperative chest X-ray demonstrated small pleural effusion occupying the lower left hemithorax, but she did not present with dyspnea or chest pain. After premedication with intravenous ranitidine 50 mg, anesthesia was induced with thiopental 150 mg, vecuronium 7 mg and maintained by 1-2% sevoflurane in 50% N2O/O2. SpO2 decreased after insufflation of CO2, but breath sound was audible on both lungs. At completion of operation, chest X-ray revealed the left hemilateral hydrothorax and 650 ml of pleural fluid was suctioned. Blood gas improved and the tracheal tube was removed. The diagnosis of tuberculous peritonitis was established by the demonstration of granulomas of the peritoneum. We speculated on four reasons for the increased pleural effusion on the left thorax: 1) Increase of systemic and capillary pressure caused by CO2 insufflation. 2) Increase of capillary permeability by tuberculous pleuritis. 3) Decrease of colloid osmotic pressure by hypoalbuminemia. 4) Decreased pleural fluid removal because of venous compression caused by increased intrathoracic pressure. Peritoneal insufflation of CO2 to create the pneumoperitoneum may induce hydrothorax in patients with tuberculous pleuritis.

Aged↗
PubMed2001

[An automated electronic anesthesia record and automated urine output measurement].

We can now collect many parameters (NIBP, HR, ABP, SpO2, EtCO2, CCO, etc) from an anesthesia monitor in an automated electronic anesthesia record system. The function of automated urine output measurement has been added to an automated electronic anesthesia record system. A digital weight meter connected with a personal computer by RS-232 C is used to measure the weight of urine. We convert the weight to the volume hypothesizing that the density of urine is 1 g.ml-1. Physiologic parameters are recorded every 10 seconds from an anesthesia monitor and we can set the period of automated urine output measurement we like. We must enter the initial and final urine output but the intraoperative urine output is collected automatically to an automated electronic anesthesia record and visualized in urine bar graph. The total volume of urine is calculated. Computerized urine output measurement can record data more frequently, for example, every 10 minute. At the end of the operation, intraoperative data are sent to a host computer and the anesthesia record is printed. Combining the automated urine output measurement with an automated electronic anesthesia record system is useful in anesthesia practice of a long operation.

Anesthesia↗