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T Shigematsu

Publications and source records attributed to T Shigematsu.

At least 109 records · Page 6Linked to original sources
PubMed1993

Parathyroid removal prevents the progression of chronic renal failure induced by high protein diet.

The influence of PTH in the progression of renal failure induced by a high protein diet was investigated in either sham operated (SHAM) or parathyroidectomized (PTX) and subtotally nephrectomized (NX) rats. NX-SHAM rats were pair-fed either a high (HPr, 40% casein) or a normal (NPr, 20% casein) protein diet and NX-PTX rats a HPr diet. The results indicate that PTX markedly improved the survival rate and prevented the deterioration of renal function induced by the HPr diet. The number of rats alive after 33 weeks was 0 of 11, 6 of 10, and 9 of 10 in NX-SHAM-HPr, NX-PTX-HPr and NX-SHAM-NPr, respectively. The increases in plasma urea and creatinine were consistently delayed or prevented in NX-PTX as compared to NX-SHAM rats fed the HPr diet. The increment in the mass and calcium content of the kidney remnant induced by HPr was prevented by parathyroidectomy. In addition, PTX completely prevented the rise in the circulating level of cholesterol observed in response to HPr. Normalization of plasma calcium in NX-PTX rats with 1,25-dihydroxyvitamin D3 restored the increment in the renal mass and calcium content and reduced the protective effect of PTX on the progression of renal failure induced by high protein diet. In conclusion, in the subtotal nephrectomized rat model of chronic renal failure, the progression of kidney damage induced by a high protein diet can be prevented by removal of the parathyroid glands. This observation suggests that PTH could be implicated in the mechanism whereby a high protein regimen accelerates the course of chronic renal failure.

Animals↗
PubMed1993

Suppression of secondary hyperparathyroidism in chronic dialysis patients by single oral weekly dose of 1,25-dihydroxycholecalciferol.

Eleven hemodialysis patients who developed refractory secondary hyperparathyroidism, despite conventional vitamin D therapy, were treated with large oral doses of 1,25-dihydroxycholecalciferol [1,25(OH)2D3]. Therapeutic regimen was a single oral dose of up to 8.0 micrograms administered once weekly following hemodialysis. A maximum serum level of 1,25(OH)2D occurred four hours after the 8.0 micrograms dose. A positive correlation (Y = 84.3X-22.1: P < 0.01) was found between the maximal serum 1,25(OH)2D concentration (Cmax) and the dose of 1,25(OH)2D3 when plotted on a logarithmic scale. Forty-eight hours after the administration of the 8.0 micrograms dose, the parathyroid hormone (PTH) level and the alkaline phosphatase activity (ALP) were markedly decreased without evidence of hypercalcemia. A significant inverse relationship was found between the Cmax of 1,25(OH)2D and the percent change in the PTH level measured after 48 hours, either with carboxy-terminal (C-PTH) or the highly sensitive mid-portion assay (HS-PTH). From these results, the level of serum 1,25(OH)2D required to blunt the rise in serum PTH was 168 pg/ml and 203 pg/ml, respectively; these serum levels were achieved by the oral administration of doses of 6.0-8.0 micrograms or higher. There were no adverse effects of treatment. Following this study, one patient was continuously treated with 8.0 micrograms of 1,25(OH)2D3 orally once a week for 18 months. There was a therapeutic effect (as evidenced by PTH suppression, ALP suppression and the disappearance of subjective complaints) without the development of severe hypercalcemia or hyperphosphatemia. This treatment may help to prevent or treat secondary hyperparathyroidism in patients receiving long-term dialysis.

Administration, Oral↗
PubMed1993

Strong synergistic effects of multicomponent vaccine for human immunodeficiency virus infection.

Several peptides were synthesized, based on sequences of the HTLV-IIIB, HTLV-IIRF, and HTLV-IIIMN strains. These corresponded to the V3 region, the killer T cell activating site, the constant region of env, gag region protein and the helper T cell activating site. Some of these peptides were coupled to keyhole limpet hemocyanin (KLH), and some of them were polymerized with m-maleimido benzoyl-N hydroxysuccinimide ester (MBS). These peptides were used to immunize rabbits and mice. Antisera from immunized animals showed good levels of inhibition of CD4-dependent cell fusion by in vitro HIV infection. The antisera also inhibited the production of p24 protein in the HIV-infected culture system. Interestingly, a strong synergistic HIV growth inhibition by antiserum was observed when we immunized animals with multicomponent vaccine. In addition, substantial levels of HIV antigen-specific IL-2 producing and interferon-gamma (IFN-gamma) producing cells were also observed in lymph node cells from vaccinated mice. These results suggest that immunization with multicomponent vaccine can induce high levels of humoral antibodies as well as activate HIV-specific cellular immunity.

AIDS Vaccines↗
PubMed1993

[Effects of sevoflurane on hemodynamics during the induction of anesthesia compared with those of isoflurane, enflurane and halothane].

The effects of sevoflurane (S), isoflurane (I), enflurane (E) and halothane (H) on hemodynamics were studied in 50 patients during the inhalation of 1.5 MAC of each anesthetic before the surgery. Mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), systemic vascular resistance index (SVRI) and stroke volume index (SVI) were measured noninvasively using the automatic blood pressure manometer and the ultrasonic Doppler method (Accucom). There were significant differences between E and H in MAP, CI, SVRI and SVI. The values of CI, SVRI, SVI with S, as well as with I, were between those of E and H. These results indicate that sevoflurane causes the depression of blood pressure mostly by decreasing afterload during the induction of anesthesia, although the decrement with sevoflurane, as well as that with isoflurane, is less than that with enflurane.

Adult↗
PubMed1993

Large cyst formation in pleomorphic adenoma.

The aim of this study was to examine about the etiology of large cyst formation in pleomorphic adenoma from the histopathological standpoint by examining four cases of our own as well as previously reported ones. In the first of our cases, a large cyst wall lined with keratinized squamous epithelium was observed. In the second, a large cyst containing mucinous material was lined with a single cell layer of squamous epithelium-like cells. The third case was a carcinoma in pleomorphic adenoma with some large cysts lined with multiple layers of atypical epithelial cells. In the fourth case, a hemorrhagic portion were seen on a large cyst wall without a lining of epithelial cells. From these histopathological observations and the suggestions of previous authors, we surmised that the large cyst formation in pleomorphic adenoma might originate from the squamous metaplasia of tumor cells and the enlargement of duct-like structures by outstanding secretion from tumor cells or salivary gland tissues, hemorrhagic portions, or necrosis in the malignant tumor.

Adenoma, Pleomorphic↗
PubMed1993

[Effect of enflurane on human somatosensory evoked potentials: differences between specific and nonspecific responses].

The effect of enflurane on somatosensory evoked potentials (SEP) was investigated in nine gynecological patients under nitrous oxide-enflurane anesthesia. SEPs were obtained from electrodes placed on the scalp C4 and earlobes by median nerve stimulation contralateral to the recording site. SEPs taken in a control study without enflurane consisted of six components; P12, N17, P23, N31, P50, and N65. Components N17, P23, N31, and P50, thought to be specific SEP responses, showed a dose-dependent increase in latencies under enflurane while P12, the initial SEP components, did not show any significant changes throughout the experiment. The longer the latency for a given response component, the greater was the increase in latency seen under enflurane anesthesia. On the other hand, N65, assumed to be a nonspecific SEP response, was completely lost with inhalation of 0.5 MAC or more of enflurane. However, the peak-to-peak amplitude between P23 and N31 was enhanced dose-dependently with enflurane up to 1.5 MAC. These results suggest that, at clinically effective doses, enflurane may inhibit nonspecific projection pathways while enhancing the primary cortical sensory area, and this enhancement may be responsible for provoking convulsive seizures under enflurane anesthesia.

Adult↗
PubMed1993

Functioning survival rate of the fixture and superstructure of osseointegrated implants (first report).

Osseointegrated implant bridges (OIB) have shown excellent progressing in the majority of cases. Since 1983, OIBs has been used to treat about 110 cases in Tokyo Dental College Hospital with more than 500 fixtures. The survival rate of OIB, especially the functioning survival rate of these fixtures, is described, herein. The survival rate of the superstructure of OIB has been almost 100% in both maxilla and mandible. However, the functioning survival rate of OIB fixtures was 88% in maxillary cases and 96% in mandibular cases at less than 1 year. Very few fixtures had to be removed after more than 1 year in either maxilla or the mandible. It appears that the functioning survival rate of OIB fixture is generally decided during the period just between connecting these components and 1 year. A few fixtures may need to be removed later.

Adolescent↗
PubMed1992

Malignant mixed Müllerian tumor of the fallopian tube: report of two cases and review of literature.

Malignant mixed Müllerian tumors are usually found in the endometrium, vagina, cervix, and ovary. It is extremely rare for this tumor to arise in the fallopian tube, and to date only 37 tubal cases have been reported. We recently experienced 2 such cases. The clinical features, pathologic findings, diagnosis, therapy, and outcome of these 39 cases were reviewed. The clinical features and diagnosis were similar to those of primary carcinoma of the fallopian tube. Correct preoperative diagnosis was difficult. Histologically, 18 patients had homologous elements and 21 had heterologous elements in the sarcomatous components. The most common type of heterologous element was cartilage, followed by striated muscle and bone. The clinical stage (FIGO staging of ovarian carcinoma) was stage I in 15 cases, stage II in 11 cases, stage III in 8 cases, stage IV in 3 cases, and unknown in 2 cases. In all the patients except 1, the tumor was surgically removed. Postoperatively, radiotherapy was given to 9 patients, chemotherapy to 9 patients, and both to 2 patients. Sixteen patients died of the disease, after a mean period of 16.1 months. Of the 15 stage I patients, 10 survived more than 12 months. The most important prognostic factor was spread of the tumor at diagnosis.

Adolescent↗
PubMed1992

Fine-needle aspiration cytology in patients with gynecologic malignancies.

Four hundred five fine-needle aspiration (FNA) cytologies were obtained from 352 sites in 287 patients with gynecologic malignancies. The majority of specimens were aspirated for recurrent or metastatic disease. The most common clinical diagnosis was cervical carcinoma (128 cases) followed by ovarian carcinoma (80 cases) and others (79 cases). The sites of FNA were lymph node (134 cases), retroperitoneal lymphocyst (57 cases), pelvic mass (52 cases), subcutaneous mass (34 cases), and others (75 cases). Of 335 sites excluding inadequate specimens, 162 (48.4%) revealed malignant cells. There was no difference in the accuracy of FNA between diseases in the superficial sites and those in the deep sites. However, the sensitivity for local recurrent diseases was lower than that for primary or metastatic diseases (86.4% vs 100.0%). The overall accuracy of FNA cytology was 95.2%, and it was satisfactory for the diagnosis of gynecologic malignant diseases. FNA should be repeated if the initial FNA specimen is inadequate for diagnosis. When distinct malignant cells are observed in FNA cytology, a biopsy may be omitted.

Biopsy, Needle↗
PubMed1992

Diet and prognosis of breast cancer.

The relationship between the occurrence of breast cancer and dietary intake, in particular a high-fat diet, has attracted much attention in recent years. In addition, the prognosis of breast cancer patients on the basis of dietary intake is also an interesting subject. The present study utilized breast cancer patients whose dietary intake was carefully assessed about one decade previously in a case-control study to determine whether dietary intake was indeed related to the patients' prognosis. The study included 212 patients who underwent a surgical operation between 1975 and 1978. They were followed-up until 1987, and a total of 47 breast cancer deaths were certified. The 5- and 10-year relative survival rates were 78.5% and 75.3%, respectively. The older patients tended to ingest smaller amounts of all nutrients, except animal fat from fish. Height was significantly correlated with total animal protein intake, whereas there was no significant correlation between body mass index and intake of any nutrient. Although the age-adjusted mean values of the nutrient intakes, other than vegetable fat, decreased with advancing stage, the differences were statistically insignificant. The results of multivariate analyses, in which some confounding factors (e.g., clinical stage) were adjusted using a proportional hazards model, showed that all hazards ratios in each nutrient were close to unity, and no dose-response relationship was seen. The present investigation did not provide any support for the hypothesis that a high-fat diet is a survival determinant for breast cancer patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Breast Neoplasms↗
PubMed1992

[Effect of isoflurane, enflurane and halothane on hemodynamics during the induction of anesthesia].

The effects of isoflurane(I), halothane(H) and enflurane(E) on hemodynamics of 36 patients (12, 11 and 13, respectively) were studied during the inhalation of 1.5 MAC of each anesthetics before the surgery. Mean arterial pressure(MAP), heart rate(HR), cardiac index(CI), systemic vascular resistance index(SVRI), and stroke volume index (SVI) were measured noninvasively using the automatic blood pressure manometer and the ultrasonic Doppler method (Accucom). MAP decreased with I, E and H, but a larger decrement was observed with E than with H. CI and SVI with H were less than with E. SVRI decreased with I and E but a significant difference was observed between E and H. Each value with I was between those with H and E. These results indicate that isoflurane causes the depression of blood pressure mostly by its effect to decrease afterload during the induction of anesthesia, although its depressing effect is less than that of enflurane.

Adult↗
PubMed1992

[A new method for endotracheal intubation with the Bullard laryngoscope].

The Bullard laryngoscope is an anatomically shaped rigid fiber optic instrument designed for indirect laryngoscopy and intubation. It requires no neck extension nor flexion to perform laryngeal intubation. This characteristic is especially useful in the case of difficult airway. The Bullard laryngoscope, however, with which it is easy to visualize the cords, has not been popular yet, because using the intubating forceps mechanism requires a certain amount of skill. The intubation method developed by us with Bullard laryngoscope has been tried on 26 patients with difficult airway and ten patients with normal airway. An endotracheal tube is inserted through nostril, and intubation is performed viewing the tube and larynx during all the processes of intubation. Three kinds of endotracheal tubes, i.e. Magill type plain tubes, styletted tubes, and directional tip tubes, are compared. The method using a directional tip tube (Endotrol) is concluded as the best among them. The Endotrol tube itself has such a suitable shape for nasal intubation that it can be introduced to the larynx with little directional change. Therefore, our method is mastered with a shorter training period than the intubation method with fiber-optic laryngoscopes. In conclusion, our intubation method with the Bullard laryngoscopes using the directional tip tubes (Endotrol) is useful for patients with difficult airways, and is also nontraumatic and easy to perform.

Humans↗
PubMed1992

[Clinical evaluation of the laryngeal mask airway using capnogram].

The laryngeal mask airway (LMA) was clinically evaluated using capnogram in patients who breathed spontaneously under the combination of general and spinal anesthesia. Using the LMA, the airway was maintained without jaw lift and no remarkable hemodynamic change was observed during its insertion and removal. Capnogram was useful to confirm the intact airway and to monitor the respiration. Respiratory depression was observed after thiopental administration and enflurane inhalation. The respiration recovered promptly following the increase of respiratory rate (RR) and tidal volume at first, and it made a further recovery following increase in RR. The use of the LMA under light inhalation anesthesia is hence a useful combination with regional anesthesia.

Adult↗
PubMed1992

[Anesthetic management of the patient with a permanent pacemaker].

Anesthetic management of two patients with a permanent pacemaker is reported; patient no. 1 had the VVI mode pacemaker and patient no. 2 had the DDD mode pacemaker. In patient no. 1, the hypotensive response of the 'pacemaker syndrome' occurred during general anesthesia. Patient no. 2 had no anesthetic problems but careful attention should be paid to the DDD mode pacemaker, because the newer widely used dual lead systems (DDD) are more susceptible to electromagnetic interference. Anesthetists often encounter patients with pacemakers. Knowledge of pacemakers available of the increasingly wide range is necessary to ensure safe management of these patients, many of whom are frail and elderly.

Aged↗
PubMed1991

[STAPHYOGRAM, a new rapid identification kit for the aerobic, gram-positive, catalase-positive cocci--application of fluorometric microplate hybridization for the pre-identification of 386 isolates used].

A new simplified test kit, STAPHYOGRAM plate, was developed for 4-hr identification of aerobic, Gram-positive and catalase-positive cocci. The plate has 18 wells, in which different dehydrated substrates and nutrients are fixed. An 18-hr agar-culture suspension of a test strain with a turbidity of McFarland No. 4 was distributed into all wells in 50-microliters quantities. After 4-hr incubation at 37C, the profile number was obtained by summarizing positive reactions. The ability of the plate to differentiate the type strains of the 30 species of the three genera in the family Micrococcaceae was confirmed. These three genera are Staphylococcus, Micrococcus and Stomatococcus. The applicability of the fluorometric microplate hybridization technique to identification of aerobic, Gram-positive and catalase-positive cocci was confirmed by homologous hybridization among the type strains of the 30 species. Thus, 386 isolates of human and animal origin were pre-identified by microplate hybridization and used for evaluating the STAPHYOGRAM plate. Of the 236 profile numbers thus obtained with the 386 isolates, 218 (92.4%) were species-proper each and all for the 15 species of Staphylococcus and Stomatococcus mucilaginosus. A total of 342 (88.6%) of the 386 isolates were given such profile numbers, and were identified without any additional test. Among the 15 species identified primarily by the results of STAPHYOGRAM plate culture, S. caprae, S. lugdunensis, S. gallinarum and S. delphini were validly published after Approved Lists of Bacterial Names. The identified strains of S. caprae (48), S. haemolyticus (46), S. capitis (35) numbered between those of S. epidermidis (67) and S. saprophyticus (31). Profile numbers common to two species were seven (27 strains) and that to four species was one (17 strains). These 44 strains were identified with one to three additional tests. From these results, we were convinced that the STAPHYOGRAM test plate is useful for the rapid identification of members of family Micrococcaceae. By compiling STAPHYOGRAM plate data on genetically identified strains, an exclusive list of profile numbers will soon be prepared for perfection of the kit.

Animals↗
PubMed1991

Ameloblastoma and its relationship to ameloblastic fibroma: their histogenesis based on an unusual case and review of the literature.

The present paper describes the relationship between ameloblastoma and ameloblastic fibroma deduced from a case diagnosed as "ameloblastoma combined with ameloblastic fibroma" arising in the mandible of a 5-year-old boy. Histologically, the tumor consisted of ameloblastoma in the central area and ameloblastic fibroma in the peripheral area; it clinically fits the characteristics of ameloblastic fibroma based on predominant age, manner of growth, and encapsulation. We reviewed the literature and discussed the relationship between ameloblastoma a ameloblastic fibroma in terms of tumorigenesis. It is assumed that ameloblastic fibroma can also be transformed into ameloblastoma, if the succeeding hard tissues are not formed, and the collagenous connective tissue substituting for the stromal mesenchymal tissue is formed by the inductive effect of the epithelial strands or other unknown factors. Several possibilities relative to the pathogenesis of ameloblastoma have been proposed by oral pathologists; however, to our knowledge, "ameloblastic fibroma can be transformed into ameloblastoma" has not hitherto been reported. The case we experienced here may be thought as an intermediate tumor pattern between ameloblastic fibroma and ameloblastoma.

Ameloblastoma↗