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T Yamaguchi

Publications and source records attributed to T Yamaguchi.

At least 505 records · Page 28Linked to original sources
PubMed1999

Mandibular-position sensation during sedation by administration of nitrous-oxide (N2O) gas.

Our aim was to confirm the influence of N2O gas on mandibular-position sensation. The subjects in this study were eight healthy adults. Each subject was asked to hold the reference stick for five seconds between the central tooth in his or her upper and lower jaws. Then, the reference stick was replaced by the test sticks with different thickness, each of which the subjects were again asked to hold at the same position for five seconds. The subjects were instructed to determine, based on judgement of the interincisal distance, whether the thickness of each test stick was larger or smaller than the reference stick. A series of trials was administered to each subject using all eight sizes of test sticks. We compared the ability of the subjects to discriminate mandibular position both before and after the application of a vibrating stimulus to the masticatory muscles, and before and during the administration of N2O gas. Discrimination ability was significantly decreased after the application of the vibrating stimulus. However, during the administration of N2O gas, no significant difference in discrimination ability was observed between before and after the vibrating stimulus. The results of this study indicated that N2O gas had an inhibitory effect on gamma-motor neuron activity, which is presumed to be mediated to some extent through the higher central nervous system. This is the case because the gamma-motor neurons are generally activated by vibrating stimuli applied to the muscle causing decreased discrimination ability of mandibular position. Thus, we conclude that mandibular-position sensation was influenced by N2O gas during the administration of N2O gas.

Adult↗
PubMed1999

Oral phosphate binders: phosphate binding capacity of iron (III) hydroxide complexes containing saccharides and their effect on the urinary excretion of calcium and phosphate in rats.

Phosphate binders that contain aluminum or calcium are frequently prescribed to treat hyperphosphatemia in patients with end-stage renal disease (ESRD), but an accumulation of aluminum can lead to encephalopathy, aluminum-related bone disease (ARBD) such as osteomalacia, anaemia, and resistance to erythropoietin, and calcium accumulation can lead to hypercalcaemia. High phosphate concentrations are reduced in vitro and in vivo by a phosphate adsorption pill, which is synthesized by hydrolyzing ferrous sulfate in the presence of saccharides, to form an iron (III)-saccharide complex that is acid resistant and binds phosphate greater than iron (III) hydroxide alone. Under in vitro conditions, containing 3.26 mg P/dL, the iron (III)-sucrose complex showed the highest phosphate adsorption capacity at pH 2 with artificial gastric juice, 58.9 mg P/g binder. For the 7 day in vivo study, 0% (Group 1), 1% (Group 2), 4% (Group 3), and 8% (Group 4) iron (III)-sucrose complex was admixed into the rodent chow by weight and fed to 15 male Wistar rats. The weight and volume of the feces and urine, and the calcium, iron, and phosphorus excretions in the feces and urine samples were monitored for any signs of irregularity. Total urine outflow was collected during a 24-h period to determine the amount of phosphate recovered, which indicates the ability of the phosphate binder to reduce gastrointestinal phosphate absorption. The fecal iron excretion was significantly effected by the amount of binder ingested throughout the study for Group 2 (p < 0.001), Group 3 (p < 0.01), and Group 4 (p < 0.001). The urinary calcium excretion (mg/rat/24-h) significantly increased by the 7th day for Group 2 (p < 0.05) and Group 4 (p < 0.01) in comparison to the control. Finally, after 7 days, there was a significant drop in the urinary phosphorus levels (mg P/rat/24-h) in a dose dependent manner for Group 2: from 7.82 +/- 1.46 to 1.98 +/- 0.10 mg P/rat/24-h (102 mg P/dL/24-h; p < 0.05); Group 3: from 6.70 +/- 1.14 to 0.16 +/- 0.09 mg P/rat/24-h (6.0 mg P/dL/24-h; p < 0.01); and Group 4: from 8.25 +/- 0.67 to 0.04 +/- 0.01 mg P/rat/24-h (0.9 mg P/dL/24-h; p < 0.01). The results show that this new adsorbent might provide an alternative to conventional aluminum and calcium containing phosphate-binding agents for combating hyperphosphataemia.

Administration, Oral↗
PubMed1999

Pancreatic phospholipase A2 induces bacterial translocation in rats.

The importance of pancreatic enzymes, particularly phospholipase A2 (PLA2), for bacterial translocation, which is considered to be one of the aggravating causes of acute pancreatitis, was investigated. Male rats were administered an intraperitoneal or intravenous injection of normal saline, PLA2, or amylase. Four days later, the mesenteric lymph nodes (MLNs) and portal blood of the animals were cultured. None of the animals had a positive portal blood culture. The MLNs contained enteric bacteria in 78% of the animals given 50 mg/kg of PLA2 intraperitoneally. 5 mg/kg of PLA2 intraperitoneally, 50 mg/kg of amylase intraperitoneally, or 50 mg/kg of PLA2 intravenously showed positive cultures in 25%, 20%, and 11%, respectively. None of the animals given intraperitoneal or intravenous normal saline had positive cultures of their MLNs. Intraperitoneal injection of 25 mg/kg of nafamostat mesilate just before intraperitoneal PLA2 (50 mg/kg) resulted in a reduction of positive MLNs from 70% to 30%. The cecal myeroperoxidase (MPO) activity of animals administered 50 mg/kg of PLA2 intraperitoneally was significantly higher compared with animals administered saline intraperitoneally. These results indicate that intraperitoneal leakage of PLA2 plays an important role in bacterial translocation during acute pancreatitis and that administration of a protease inhibitor may be effective against the bacterial translocation.

Acute Disease↗
PubMed1999

Differential distribution of T lymphocyte subpopulations in the bovine mammary gland during lactation.

The existence and distribution of T lymphocyte subpopulations in the mammary parenchymal tissue of cows were immunohistochemically detailed during early lactation. CD2+, CD4+, and CD8+ T lymphocytes were localized primarily in the mammary parenchymal tissue. CD8+ T lymphocytes were predominant over CD4+ T lymphocytes and occurred in close contact with the alveolar epithelium and between epithelial cells in the central area of the upper mammary gland. CD4+ T lymphocytes were present in equal numbers in the epithelial and connective tissue area. Occasionally, both CD4+ and CD8+ T lymphocytes formed cell clusters in the interalveolar connective tissue. The ratio of CD4+ T lymphocytes to CD8+ T lymphocytes was less than 1.0 and was lower in the epithelial area than in the connective tissue. The distribution of CD4+ and CD8+ T lymphocytes was similar in the parenchymal tissue of the gland cistern. The observation that there is a preferential presence of CD8+ T lymphocytes in the epithelial area of the bovine mammary gland during early lactation might indicate that these cells participate in the maintenance of the integrity of the epithelium.

Animals↗
PubMed1999

[Long-term follow-up of a bladder exstrophy case after successful repair].

We present a female case of bladder exstrophy where the patient was followed up for 15 years. In 1982 primary closure of the bladder and urethra with bilateral iliotomy by the posterior approach was performed at the age of 4 months. However, realignment was necessary, since the wound split open postoperatively. We used a corset specially prepared for this patient to prevent wound dehiscence during the subsequent postoperative course. Four years later, VUR was surgically eradicated. At the age of 9 years old, her bladder function was satisfactory, demonstrating a normal CM pattern with synergia and Pmax 128 cm H2O on UPP. She had no urge or stress incontinence. The most recent IVP and DMSA renal scan revealed almost normal findings. VCUG showed no VUR and renal function tests (PSP, Ccr 24) also confirmed no interval deterioration. We believe that the approximation of the intersymphyseal band at the time of bladder neck closure is the single most important factor for ensuring urinary continence.

Bladder Exstrophy↗
PubMed1999

[Effectiveness of isoniazid inhalation in patients with endobronchial tuberculosis].

The clinical effectiveness of isoniazid (INH) inhalation was studied retrospectively in 34 patients with endobronchial tuberculosis. Diagnoses of endobronchial tuberculosis and assessments of bronchial stenosis were based on bronchoscopic examinations. We divided the patients into 2 groups: 13 who received systemic chemotherapy for lung tuberculosis only, and 21 who received systemic chemotherapy combined with INH inhalation (200 mg/day). No significant differences distinguished the groups with respect to duration of positive sputum culture or ESR normalization. However, a significant alleviation of bronchial stenosis and earlier reduction of respiratory symptoms were observed in the patients who received systemic chemotherapy with INH inhalation. We concluded that INH inhalation in addition to standard therapy for lung tuberculosis is effective in patients with endobronchial tuberculosis.

Administration, Inhalation↗
PubMed1999

Association of an insertion polymorphism of angiotensin-converting enzyme gene with the activity of lupus nephritis.

BACKGROUND: Lupus nephritis is a common manifestation of systemic lupus erythematosus (SLE). The pathogenesis of lupus nephritis has not been fully understood; however, immunological abnormalities have been considered in the development and activity of lupus nephritis. As angiotensin-converting enzyme (ACE) is implicated in various immunological phenomena, we investigated the correlation between insertion (I)/ deletion (D) polymorphism of the ACE gene and the activity of lupus nephritis. PATIENTS AND METHODS: Eighty-four patients with SLE and 100 healthy subjects were enrolled in this study. Following the extraction of genomic DNA from the peripheral blood, the ACE genotype was determined by the polymerase chain reaction. The patients were classified by the histological findings according to the WHO classification. In addition, the activity index and chronicity index were used to assess the severity of renal involvement. RESULTS: Individuals with II genotype showed a significantly increased activity of lupus nephritis. The allelic frequency was I/D = 0.84/0.16 in patients with WHO class IV renal lesions, and I/D = 0.36/0.64 in those with WHO class I lesions and 0.61/0.39 in patients with WHO class I or WHO class II. The difference in the allelic frequency between patients with WHO class IV and those with WHO class I or WHO class I + WHO class II was statistically significant (p = 0.00016 or p = 0.027, respectively). Moreover, lupus nephritis patients with II genotype showed significantly higher activity index than those with DD genotype (p = 0.0009). CONCLUSION: These results suggest that the insertion polymorphism of the ACE gene may correlate with the activity of lupus nephritis.

Adult↗
PubMed1999

[Development of cancer treatment practice guidelines in Japan: advantages and disadvantages].

The development of clinical practice guidelines for the systematic treatment of cancer is being promoted as a way to assist clinicians and patients. In this paper, the advantages and disadvantages of developing clinical practice guidelines for both clinicians and patients are discussed. Physicians may regard guidelines to be unrealistic, and some may even consider guidelines to be a challenge to their autonomy. However, the advantages of guidelines for the patients and clinicians exceed any disadvantages. The development of guidelines should therefore be promoted, although with consideration of both the many advantages and disadvantages for clinicians and patients.

Diagnosis-Related Groups↗
PubMed1999

[Treatment of postoperative recurrence of digestive cancers: peritonitis carcinomatosa].

Carcinomatous peritonitis is the most frequent type of recurrence observed after surgery for cancer of the digestive tract. Most patients with carcinomatous peritonitis present with bowel obstruction and/or ascites. Surgical treatment including colostomy and intestinal anastomosis and chemotherapy have been attempted in patients with carcinomatous peritonitis, although the results have not been satisfactory. New drug delivery systems, such as mitomycin C-adsorbed charcoal, anticancer drugs entrapped in microspheres, and immunoconjugates composed of anticancer drugs and antibodies, will be powerful new tools for the treatment of metastatic cancer.

Digestive System Neoplasms↗
PubMed1999

Severe phenotype of neurofibromatosis type 2 in a patient with a 7.4-MB constitutional deletion on chromosome 22: possible localization of a neurofibromatosis type 2 modifier gene?

Neurofibromatosis type 2 (NF2) is an autosomal dominant disorder predisposing to multiple neoplastic lesions with the hallmark of schwannoma arising at the eighth cranial nerve. NF2 shows a distinct clinical variability, with a mild and a severe form of the disease. The NF2 gene is mutated in constitutional DNA of affected patients from NF2 families and in sporadic cases. Comprehensive mutation analyses in patients with severe and mild phenotypes revealed mutations in only 34%-66%. In the remaining fraction, the genetic mechanism behind the development of NF2 is unknown. Analyses of germline mutations do not provide a conclusive explanation for the observed clinical heterogeneity of NF2. It can therefore be hypothesized that other factors, e.g., modifier gene(s), contribute to the development of a more severe NF2 phenotype. We report a mentally retarded patient with the severe form of NF2 who displays a 7.4 million base pair deletion on chromosome 22. We performed a full genetic characterization of this case using heterozygozity analysis of 41 markers from chromosome 22, detailed FISH mapping of deletion breakpoints, allelotyping of all other chromosomes, and sequencing of the NF2 gene in tumor DNA. Two genomically large deletions similar in size (700-800 kb), which encompass the entire NF2 gene, have been reported previously in mildly affected NF2 patients. The centromeric breakpoints of these deletions were similar to the centromeric breakpoint in the present case. However, the deletion in our patient extends over a much larger distance toward the telomere of 22q. Our results support the existence of NF2 modifier gene(s) and suggest that such a putative locus maps to a 6.5-MB interval on 22q, between D22S32 and the MB gene.

Adult↗
PubMed1999

[Development of a sensitive enzyme immunoassay for protein 1/Clara cell 10 kDa protein using monoclonal antibodies].

Protein 1 (P1)/Clara cell 10 kDa protein is a dimer of identical subunits of 70 amino acids. Designed to expand its clinical significance, a sensitive sandwich enzyme-linked immunosorbent assay (ELISA) for P1 was developed using two monoclonal antibodies, which were recently generated and characterized in this laboratory. The precision, reproducibility and specificity of the assay were quite satisfactory. Species specificity was also satisfactory. The detection sensitivity was 5 ng/l; high enough to quantify P1 in several body fluids. P1 was distributed in the value of 13 to 25 micrograms/l, 153-4300 micrograms/l and 145-8600 micrograms/l, in serum, bronchoalveolar lavage fluids and seminal fluids, respectively.

Adult↗
PubMed1999

[A case with frequent episodes of transient ischemic attack presenting the Wallenberg syndrome before and after the onset of brain infarction].

A 52-year-old man with diabetes mellitus, hyperlipidemia and smoking habit, experienced transient ischemic attacks (TIAs) with symptoms of left orbital pain, left blepharoptosis and hoarseness lasting for five minutes on March 10, 1997. Subsequently, the same symptoms repeated once or twice daily. On March 28, he had dysphagia, numbness and disturbance of pain and temperature sensation (segmental dissociated sensory disturbance) on the right side of the body above the level of the Th10, the right upper limb and face. The deficits persisted for more than 24 hours. Angiographic studies revealed an occlusion of the left vertebral artery immediately after branching of the posterior inferior cerebellar artery. MRI demonstrated a hyperintense lesion on MRI T2 weighted image in the left lateral medulla. About three months after the completed stroke, he had six episodes of TIAs of left Horner's sign and hoarseness. To our knowledge, this is the rare case that had frequent TIAs presenting the Wallenberg syndrome before and after the onset of lateral medullary infarction. We speculate that the TIAs resulted from microembolism from the proximal end of occluted left vertebral artery and failure of the microcirculation in and around the lateral portion of the medulla oblongata.

Cerebral Infarction↗
PubMed1999

[Pronounced progression of interstitial pneumonia in a precious metal worker].

A 43-year-old man who had been engaged in the precious-metal processing industry for 18 years was admitted to our hospital because of shortness of breath on exertion. Chest roentgenograms disclosed ground glass opacities and annular-nodular shadows in the basal area of the right lung field and almost all of the left lung field. A video-assisted thoracoscopic lung biopsy was performed, and histologic examination disclosed usual interstitial pneumonia (UIP). Mineral analysis revealed high modes of silicon and aluminum, two elements consistent with the materials used in the patient's factory. The histopathological findings indicated interstitial pneumonia caused by the inhalation of dust particles. After corticosteroid therapy, computed tomographic scans disclosed that the ground glass opacities had subsided, but that honeycomb shadows remained. A chest roentgenogram taken 2 years earlier demonstrated only minute granular lesions in the basal area of right lung field. The interstitial shadows had progressed significantly over the intervening 2-year span. The findings in this case should be of value to the etiologic study of UIP.

Adult↗
PubMed1999

[Efficacy of hemostatic puncture closing device for hemostasis and early ambulation after coronary angiography and angioplasty: results of a multicenter trial].

To assess the efficacy and safety of a hemostatic puncture closing device for reducing patient immobilization after cardiac catheterization from a percutaneous femoral artery approach, we conducted a prospective, randomized trial at 4 participating centers. A total of 240 patients (183 men, 57 women, mean age 61 +/- 10 yr; 157 patients underwent diagnostic angiography, 83 patients underwent coronary angioplasty) were randomized to either the device group (n = 120) or the manual compression group (n = 120). There were no statistical differences in age, gender, weight or sheath size between the 2 groups. A 7, 8F sheath was used in 53 patients of the device group and in 43 patients of the manual compression group. One hundred and two patients (85%) in the device group and 96 patients (80%) in the manual compression group received heparin. Protamine was used in one patient of the device group and 23 patients of the manual compression group. Activated clotting time just prior to sheath removal was 206 +/- 64 sec in the device group and 170 +/- 47 sec in the manual compression group (p < 0.01). Successful placement of the device was achieved in 118 of 120 patients (98%). Time to hemostasis was significantly shorter in the device group (0.8 +/- 3.2 vs 12.2 +/- 5.3 min, p < 0.01). Time to ambulation could be reduced in the device group (5.3 +/- 3.7 vs 10.9 +/- 5.1 hr, p < 0.01). The following complication rates occurred in the device group as compared with the manual compression group: hematoma, 16% vs 10%; bleeding, 8% vs 3%; pseudoaneurysm, 0% vs 1%, respectively. None of these differences was statistically significant. These results indicate that early ambulation using a hemostatic puncture closing device is feasible without significantly increasing the risk of peripheral vascular complications.

Adult↗
PubMed1999

Topographic analysis of inner ear lesions in profoundly deafened patients with tympanogenic and meningogenic labyrinthitis using three-dimensional magnetic resonance imaging.

OBJECTIVE: High-resolution magnetic resonance imaging (MRI) provided clear images of three-dimensional (3D) reconstruction of the inner ear in candidates for cochlear implantation. In this study. semiquantitative analysis of the 3D MRI findings was performed to investigate topographic lesions of the inner ear caused by tympanogenic and meningogenic labyrinthitis. STUDY DESIGN: This was an observational study. SETTING: The study was performed in an academic, comprehensive, multispecialty group practice. PATIENTS: Postlingual deafened patients with cochlear implantation. The cause of deafness was tympanogenic or meningogenic labyrinthitis. INTERVENTION: High-resolution 3D MRI and postoperative speech recognition tests were used. RESULTS: Abnormal findings in the inner ear detected with MRI were found before surgery in 58.3% of the patients with meningogenic labyrinthitis, although the incidence was lower in patients with tympanogenic labyrinthitis. Abnormal MRI findings were frequently observed in the cochlear basal turn and semicircular canals more than in the middle and apical turn in cases with meningogenic etiology. Patients with tympanogenic labyrinthitis suffered less with a vestibular apparatus than did those patients with meningogenic labyrinthitis. Regarding the analysis of the inner ear lesions at the implanted side, the postoperative speech recognition ability did not correlate to the extent of abnormal MRI findings of the implanted ear. CONCLUSION: Improvement in 3D MRI technology provided an accurate preoperative picture of the inner ear apparatus. In cochlear implant patients with infectious labyrinthitis, the extent of the inner ear lesion detected with 3D MRI was different among etiologies of deafness.

Adult↗