Search PubMed⌕ Search

Biomedical subjects

A Niimi

Publications and source records attributed to A Niimi.

At least 73 records · Page 4Linked to original sources
PubMed1993

Intra- and extraoral prostheses using osseointegrated implants after maxillofacial surgery.

Maxillary and orbital defects due to the resection of maxillary tumors in six cases were treated utilizing maxillofacial prostheses employing pure titanium osseointegrated implants (Brãnemark system). A total of 17 fixtures were installed in the maxillary region, and 16 achieved osseointegration. For the orbital region, nine fixtures were installed, and all fixtures integrated well. Using these fixtures as anchors, four maxillary prostheses and three orbital prostheses were set. The stability of the prostheses were improved by anchors, and the prostheses were highly satisfactory to the patients.

Adult↗
PubMed1993

Masticatory improvement using osseointegrated implants: analysis of Japanese patients' responses through questionnaires.

Masticatory improvement obtained by the use of osseointegrated implants (Brånemark System) was analyzed through questionnaires collected from 22 Japanese patients. The questionnaires were designed to assess mastication of different Japanese foods. The postoperative score of masticatory function obtained by analysis of the questionnaires was 90.9, as opposed to the preoperative score of 43.9. A multiple regression analysis indicated that the number of placed implants has no significant effect on the improvement of masticatory function, whereas preoperative performance does. Further, the degree of masticatory improvement showed variation according to the condition of the dental arch opposing the implant prostheses. The group having implant prostheses in the opposing arch showed the highest improvement.

Adult↗
PubMed1993

[Clinical features of pulmonary Mycobacterium kansasii infection: comparison with M. tuberculosis and M. avium complex infection].

Six cases of pulmonary M. kansasii infection were studied. The ages of the patients ranged from 26 to 51, with a mean of 39.6 years. All the patients were male. None had any underlying systemic or lung diseases. On chest X-ray and CT scan, the majority of cases showed a solitary thin-walled cavitary lesion with little satellite or scattered lesions, which were predominantly located in S1 or S2. The strains of M. kansasii isolated from the 6 patients showed a certain pattern of antibiotic sensitivity being highly sensitive to TH, CS, EB and RFP. In 5 out of the 6 patients, chemotherapy with RFP combined with 2 or 3 other antituberculous drugs for 12 months was successful. In another patient, chemotherapy with RFP, EB and INH for 12 months was unsuccessful and surgical resection was required. Comparison of patients with M. kansasii (n = 6), M. tuberculosis (n = 112) and M. avium complex infection (n = 51) revealed that the former two had some common clinical features: predominance in males, younger age than the patients with M. avium complex infection, predominant involvement of S1, S2 and S6, and involving a single rather than multiple lung lobes. Even in cases clinically suspected of having M. tuberculosis infection, bacteriological examination should be carried out routinely to rule out M. kansasii infection.

Adult↗
PubMed1993

[Airway inflammatory cell dynamics during late asthmatic reactions induced by toluene diisocyanate in guinea pigs. I. Bronchoalveolar lavage study].

We developed a guinea pig model of late asthmatic reactions (LAR) induced by toluene diisocyanate (TDI), and investigated airway inflammatory cell dynamics during LAR by bronchoalveolar lavage (BAL) in this model. The guinea pigs were sensitized by nasal application of 10% TDI solution once daily for 7 consecutive days. Thereafter, the animals were challenged with 5% TDI solution, in the same manner, on every 7th day for 4 to 11 times. Each guinea pig was pretreated with metyrapone before challenge. BAL was performed at each time point after the final challenge. The immediate asthmatic reaction and the LAR induced in the challenges were found to be 66% and 55%, respectively. A significant BAL fluid eosinophilia was observed in the guinea pigs during and after LAR (i.e., 3, 6, 24 and 168 hours after challenge), in comparison to the animals without LAR and to the control animals only exposed to ethyl acetate, a solvent for TDI. The number of eosinophils peaked at 6 hours after challenge. However, no significant changes were observed in the numbers of macrophages, lymphocytes or neutrophils in BAL fluid during LAR. We conclude that eosinophils play an important role in LAR in this model. This model seems to be useful in investigating the pathophysiology of TDI-induced asthma.

Animals↗
PubMed1993

[Airway inflammatory cell dynamics during late asthmatic reactions induced by toluene diisocyanate in guinea pigs. II. Histological study].

We investigated airway inflammatory cell dynamics during late asthmatic reactions (LAR) induced by toluene diisocyanate (TDI) in a guinea pig model developed by K. Tanaka et al. (Bull. Chest Dis. Res. Inst. Kyoto Univ. 1983: 16: 1-9). For sensitization, 10% TDI solution was applied once daily to the bilateral nasal mucosa of 41 guinea pigs for 7 consecutive days. One week after the sensitization, the animals were challenged with 5% TDI solution once a week. In addition, metyrapone (50 mg/kg) was injected intraperitoneally 24 h, and 30 min before the challenge, respectively. Airway tissue specimens (large bronchi and bronchioles) were obtained from the 41 guinea pigs at each time point (30 min, 3, 6, 24 and 168 h) after the challenge. Airway inflammatory cell dynamics were evaluated with regard to the onset and persistence of LAR. As a control, 7 guinea pigs were only exposed to ethyl acetate (a solvent for TDI) and sacrificed 6 h afterward. A histological examination of the airways revealed remarkable infiltration of eosinophils but failed to demonstrate infiltration of other inflammatory cells, including neutrophils, in the mucosal tissues of the bronchi and bronchioles during LAR at any time point (3, 6 and 24 h) after the challenge. Therefore, we conclude that eosinophils, but not neutrophils, play an important role in LAR in our model, a contrast to previous reports on human TDI-induced LAR in which neutrophils were also involved.

Animals↗
PubMed1992

Relationship between endothelin and thromboxane A2 in rat liver microcirculation.

In our previous study, we determined changes in hepatic blood flow using a Laser Doppler blood flow meter after i.v. injection of endothelin-1 (ET-1) or endothelin-3 (ET-3) at 2 nmol/kg in rats and found that ET-3 caused greater decreases in blood flow than ET-1. In the present study, we determined how the arachidonic acid cascade, mainly thromboxane A2 (TXA2), is related to ET-1 and ET-3 using indomethacin (INDO), which inhibits the biosynthesis of prostaglandin (PG), and OKY-046, a selective inhibitor of TXA2 synthesis. In the first series of experiments, ET-1 and ET-3 were administered after inhibiting the biosynthesis of PG by s.c. injection of 2 mg/kg of INDO. While INDO failed to inhibit the slight decrease in hepatic blood flow induced by ET-1, it significantly inhibited the marked decrease in hepatic blood flow elicited by ET-3. In the next series of experiments, ET-1 and ET-3 were administered after administration of 20 mg/kg of OKY-046. OKY-046 showed no effects in animals treated with ET-1, as in those pre-treated with INDO, while it significantly inhibited the decreases in hepatic blood flow induced by ET-3. These findings suggest that ET-1 decreases hepatic blood flow due to its direct effects although to a lesser extent than ET-3, while ET-3 does so due not only to its direct effects but also to TXA2-mediated effects. It is therefore likely that in addition to ET family peptides, PG-mediated mechanisms are involved in the regulation of hepatic microcirculation by ETs.

Animals↗
PubMed1992

ET-3 sensitive reduction of tissue blood flow in rat liver.

Changes in gastric mucosal and hepatic tissue blood flow were simultaneously determined using a laser-Doppler blood flow meter in rats given i.v. injection of endothelin-1 (ET-1) and endothelin-3 (ET-3), both at 2 nmol/kg. Gastric mucosal blood flow decreased significantly after administration of ET-1 compared to after administration of ET-3. Decreases in blood flow due to ET-1 were reversed by pre-treatment with 10 mg/kg of BQ-123 (sodium salt), an ETA receptor antagonist, to levels comparable to those induced by ET-3, but BQ-123 had no effects on decreases in blood flow due to ET-3. On the other hand, decreases in hepatic tissue blood flow by ET-3 were significant compared to those by ET-1. Decreases in hepatic tissue blood flow due to ET-1 were slightly inhibited by pre-treatment with 10 mg/kg of BQ-123, but it had no effect at all on decreases due to ET-3. These findings indicate that decreases in gastric mucosal blood flow are mainly caused by ET-1 via ETA receptors inhibited by BQ-123, while decreases in hepatic tissue blood flow are caused mainly by ET-3 via non-ETA receptors not inhibited by BQ-123. The fact that ET-3 decreases blood flow more significantly than ET-1 suggests the involvement of ET-3 selective receptors (ETc). The findings obtained in the present study indicate that complex mechanisms are involved in the regulation of tissue blood flow by ET, with different receptor subtypes and ET family peptides being involved according to the type of tissue.

Animals↗
PubMed1992

[Two cases of idiopathic pulmonary hemosiderosis: analysis of chest CT findings].

Chest CT findings are reported in two cases of idiopathic pulmonary hemosiderosis. In both cases, CT was performed after remission of an acute exacerbation following corticosteroid therapy. Case 1 was a 17-year-old woman with Down's syndrome. Chest radiograph showed diffuse ground-glass like and reticulonodular shadows, which were predominant in the bilateral lower lung fields. Chest CT showed a diffuse increase of lung filed density, especially in the dorsal zone of both lower lobes. Open lung biopsy revealed hemorrhage and numerous hemosiderin-laden macrophages in the alveoli, and in addition, marked fibrous thickening of the alveolar septa. Case 2 was a 7-year-old girl. Chest radiograph showed diffuse micronodular shadows in both lungs. Chest CT showed diffuse poorly-circumscribed micronodular lesions with uniform distribution, and lung field density was normal except for the right upper lobe with patchy infiltrates. Although lung biopsy was not performed, fibrous thickening of the alveolar septa was presumed to be mild even if present, since pulmonary function and blood gas analysis were within normal limits. In these two cases, lung field density of CT seemed to reflect the degree of diffuse fibrous thickening of the alveolar septa, and it is suggested that CT is valuable in the evaluation of fibrous thickening of the alveolar septa secondary to recurrent pulmonary hemorrhages. Comprehensive review of CT findings of idiopathic pulmonary hemosiderosis was also performed.

Adolescent↗
PubMed1992

[Two cases of pericardial diverticulum].

Two cases of resection of pericardial diverticulum are reported. The lesion was located in the right upper mediastinum in case 1 (66-year-old woman) and at the right anterior cardio-phrenic angle in case 2 (20-year-old woman). In case 1, the shape of the lesion varied on fluoroscopic observation when the position of the patient was changed, and in case 2, ICG instilled into the lesion operation diffused into the pericardial cavity. These procedures seemed to be useful in the diagnosis of pericardial diverticulum, differentiating it from pericardial cyst.

Adult↗
PubMed1992

[Clinical study on cough variant asthma].

Chronic cough may be the sole presenting manifestation of bronchial asthma (reference 3; Corrao et al, 1979), and "cough variant asthma (CVA)" has been used to categorize such patients. In order to clarify the clinical picture of CVA, we evaluated the clinical history, laboratory data, sputum cytology and pulmonary function in 14 subjects (5 males and 9 females, aged 14 to 65 years) compatible with the following diagnostic criteria: (1) chronic cough persistent for more than 8 weeks, (2) no wheeze nor dyspnea, (3) no rales, (4) no past history of asthma, (5) bronchial hyperreactivity to methacholine proven by Takishima's method (reference 13), (6) effectiveness of bronchodilators against cough, (7) normal chest X-ray film, (8) afebrile and negative CRP, (9) absence of sinusitis and postnasal drip, or if present, they are proved not to be responsible for the cough, and (10) no other causes of cough such as heart disease, prescription of ACE inhibitors, current smoking. The results were as follows. 1) Many of the subjects were atopic, with positive skin tests to one or more common allergens in 10 subjects, elevated serum IgE in 4 subjects, and past history and family history of atopy in 4 and 7 subjects, respectively. 2) Respiratory infection preceded the onset of CVA in 3 subjects. 3) Cough was generally nocturnal, but 2 subjects coughed only in the daytime. 4) FEV1.0% was decreased (less than 70%) in only 2 subjects, whereas V25 was decreased (less than 80% of predicted value) in 11 out of 12 evaluable subjects, which suggested peripheral airway obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

[A clinical study on coexistence of active pulmonary tuberculosis and lung cancer].

Twenty-two patients were diagnosed as coexisting active pulmonary tuberculosis and lung cancer during last ten years until 1989. They were nineteen men and three women and their age ranged from 61 to 84 years with a mean age of 71.3. Six patients had history of tuberculosis, three had undergone gastrectomy and four patients were complicated with diabetes mellitus. Histological types of lung cancer were epidermoid cell carcinoma in 13, adenocarcinoma in 3, large cell carcinoma in 2, and small cell carcinoma in 4 and clinical stages were "stage I" in 2, "stage II" in 2, "stage IIIA" in 5, "stage IIIB" in 4 and "stage IV" in 7, except 2 patients after surgical treatment. Localizations of lesions of cancer and tuberculosis were in the same lobes in 6, in ipsilateral lung in 6, and in contralateral lung in 6, except 4 cases, whose lesion of tuberculosis was not detectable roentgenologically and all cancers of "same lobe" cases were peripheral origins. Although, the prognosis was poor, which reflects the prognosis of lung cancer as a whole, the efficacy of anti-tuberculous chemotherapy was as good as patients without lung cancer. We mainly discussed the diagnostic points to detect the coexistence of lung cancer and pulmonary tuberculosis at early stage.

Aged↗
PubMed1992

[A resuscitated case of sleep apnea syndrome with cardiac arrest].

A 71-year-old man was noted to habitually snore loudly at night and have a predisposition to somnolence during the daytime. While dozing during the day, he developed cardiac arrest at the time when snoring stopped, and was resuscitated. By means of a respiration monitor, he was diagnosed as having sleep apnea syndrome (SAS) with a combination of obstructive, central, and mixed type. However, neither respiratory insufficiency nor cardiac insufficiency was observed, and there were no abnormal findings on laboratory tests and bronchoscopy. SAS complicated by cardiac arrest is usually seen in cases with concomitant symptoms such as excessive obesity, hypertension, arrhythmia, right heart insufficiency, secondary polycythemia, or mental disorder. The present case abruptly developed cardiac arrest in the absence of such symptoms. This case therefore suggests the importance of screening tests using a respiration monitor during sleep in subjects who have a loud snore or a predisposition to somnolence during the daytime. Although treatment with UPPP alone had no noticeable effect, UPPP treatment combined with sleeping in the lateral position was effective in the present case. The efficacy rate of UPPP has been reported to be 50 to 60%. The early establishment of a method for precise evaluation of the site of obstruction as well as criteria for appropriate application of UPPP are urgently required.

Aged↗
PubMed1990

Immunohistochemical analysis of inflammatory infiltrates around the injection site of a streptococcal preparation, OK-432, in rat tongue.

On the assumption that neutrophils around the injection site of OK-432, a heat- and penicillin-treated lyophilized preparation of the Su strain of Streptococcus pyogenes, enhance immunologic response through the production of Interleukin-1 (IL-1), OK-432 was injected into rat tongue, and specimens from the tongue were immunohistochemically investigated at various intervals after the injection, to clarify the process of inflammatory and immune responses at the injection site. Neutrophils and mononuclear cells appeared around the OK-432 injection site after 1 hour, increased to their maximum level at 24 hours, and then decreased from the 3rd to the 7th day. IL-1 was detected on neutrophils 3 hours after the injection, and OX-08-positive cells (suppressor/cytotoxic T cells and the majority of natural killer cells) remarkably increased. OX-39-positive cells (IL-2 receptor) appeared after 12 hours. These results suggest that neutrophils around the injection site of OK-432 at early phases of inflammation play a role in the expression of BRM function through IL-1.

Acute-Phase Reaction↗
PubMed1990

Immunohistochemical analysis of effects of cyclosporin A on gingival epithelium.

Cyclosporin A (CSA)-induced gingival overgrowth was immunohistochemically compared with that phenytoin-induced and nonspecific inflammatory gingiva, and CSA concentration was determined for dental plaque. Leu-6+ epithelial dendric cells (EDC) were found to significantly decrease in number in CSA-induced gingival overgrowth, while the ratio of HLA-DR+ EDC to Leu-6+ EDC did not change significantly. The expression of class II major histocompatibility complex antigens, such as HLA-DR, -DP and -DQ on keratinocytes did not change by CSA-treatment. Leu-4+ mononuclear cells in CSA-induced gingival overgrowth were located primarily in the connective tissue far outside the epithelium. CSA concentration was much higher in dental plaque than in blood and other tissues. Immune response thus appears to be suppressed in the epithelial layer of CSA-induced gingival overgrowth through decrease in Leu-6+ HLA-DR+ EDC and T cell infiltration, both due to CSA in dental plaque. DNA polymerase alpha was detected in much fewer basal keratinocytes of CSA- and phenytoin-induced gingival overgrowth. Epithelial hyperplasia may thus be not due to increased keratinocyte proliferation, but rather to enhanced keratinocyte life span.

Adolescent↗
PubMed1990

[Diagnostic value of bronchoalveolar lavage in fat embolism syndrome--a case report].

On the basis of the studies of autopsy cases and experimental animals, the pulmonary pathological findings of fat embolism syndrome (FES) have been reported to be (1) fat globules in the alveolar capillaries and the alveoli, (2) intra-alveolar hemorrhage, (3) alveolar edema and (4) foci of secondary infection. However, reports on lung biopsy in FES are rare, and no report has mentioned bronchoalveolar lavage (BAL) in FES. We experienced a case of FES, in which BAL was diagnostic. A 23 year-old man traffic accident victim was brought to our hospital by ambulance. His consciousness was clear and skeletal X-ray films revealed multiple fractures of the right femur, left tibia and left fibula. Direct traction of bilateral lower extremities was done. He remained stable subjectively, but anemia and thrombocytopenia progressed gradually in spite of blood transfusion. On the 4th hospital day severe hypoxemia, diffuse pulmonary infiltrates and petechiae in bilateral axillary lesions appeared, and FES was strongly suspected. O2 inhalation by face mask and high dose methylprednisolone administration was started. The hypoxemia improved, but pulmonary infiltrates worsened. For differential diagnosis, bronchoscopy and BAL was done on the 7th hospital day. Bronchoscopy revealed much fresh blood in the left main, upper lobe and lower lobe bronchus but no bleeding point was found. BAL fluid was bloody. The Sudan III stain and Berlin blue stain revealed several fat globules and numerous hemosiderin-laden macrophages. The presence of intra-alveolar fat globules and intra-alveolar hemorrhage was proved and definite diagnosis of FES was established.

Adult↗
PubMed1989

[Localization of pancreatic insulinomas by combined radiographic methods].

Seventeen cases with a total of eighteen insulinomas were examined by ultrasonography (US), computed tomography (CT), angiography, percutaneous transhepatic portal and pancreatic venous sampling (PTPS) and intraoperative ultrasonography (IOUS). We discussed about diagnostic accuracy of insulinomas on these diagnostic modalities. Tumor localization was achieved by US in 39%, CT in 72% and angiography in 81%. Although total 15 tumors (83%) can be correctly detected, multiple lesions were not completely ruled out. We recommended the criteria in PTPS as follows: Insulin concentration level above 200 mu U/ml. Or, both of insulin concentration ratio (step-up site/control) above three and elevation of the CPR concentration level on the PTPS. According to these criteria, the accuracy rate was 91%. Overall preoperative diagnostic accuracy was 100%. IOUS allowed us to detect the localization of the tumors completely.

Adenoma, Islet Cell↗