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K Nishimura

Publications and source records attributed to K Nishimura.

At least 721 records · Page 40Linked to original sources
PubMed1991

Initial gingival tissue attachment to the deep cementum.

This study was performed in order to obtain fundamental knowledge regarding gingival connective tissue response to cementum. Gingival tissues of monkeys were elevated, and superficial cementum only was curetted. The time course of initial gingival tissue attachment was subsequently examined by conventional histology and also by electron microscopy. The first response was inflammatory exudate and fibrin attachment followed by granulation tissue formation. Cementoblasts were observed along the curetted cementum surface in the 10-day specimen. Mature collagen fibrils accumulated between the cementoblasts and the cementum surface in the 14-day specimen. We conclude that curetting the superficial cementum from root surfaces facilitates the formation of the fibrous connective tissue attachment.

Animals↗
PubMed1991

An ultrastructural study comparing new gingival tissue attachment on chemically exposed fibrils and retained periodontal ligament.

Successful periodontal healing has been demonstrated in animals following application of citric acid to exposed root surface. However, we have been unable to achieve comparable results on clinical patients. Accordingly, the present study, using monkeys, was designed to re-evaluate the degree of interdigitation of newly-formed gingival fibrils with ones exposed to citric acid compared to normal attachment tissues of the retained periodontal ligament. We found that superficial collagen fibrils in both cases suffer degradation following normal inflammation and healing secondary to flap surgery. On retained periodontal ligament tissues, this change was limited to superficial levels and newly-formed collagen fibrils were linked immediately with old ones. In contrast, when exposed collagen fibrils were conditioned by exposure to citric acid, the degradative change occurred more deeply, and healing was delayed. Thus, the citric acid may not be the best choice of root treatments in terms of promoting better gingival tissue attachment. Furthermore, the results indicated that fibrils preserved on the root should not be curetted as possible during flap surgery as they offer an improved chance for optimal reattachment.

Animals↗
PubMed1991

Does atrial appendectomy aggravate secretory function of atrial natriuretic polypeptide?

The present study was designed to clarify how atrial appendectomy affects hemodynamics and secretory function of atrial natriuretic polypeptide in the failing heart. Eleven mongrel dogs were prepared for the experimental model of high-output heart failure by creation of arteriovenous fistulas between femoral arteries and veins. Two months after the first operation, effects of bilateral atrial appendectomies on basal and pacing-induced secretions of atrial natriuretic polypeptide were investigated in five dogs with simultaneous measurement of various hemodynamic indices. In the remaining six dogs, used as a control group, pacing-induced secretion of atrial natriuretic polypeptide was examined in the same way as in the appendectomy group. After excision of the atrial appendages, neither systolic blood pressure nor either atrial pressure changed, but plasma atrial natriuretic polypeptide level was decreased (292 +/- 54 to 188 +/- 47 pg/ml, p less than 0.01) and cardiac output fell (3.7 +/- 0.9 to 3.0 +/- 0.8 L/min, p less than 0.01). During pacing-induced tachycardia, the peak level of plasma atrial natriuretic polypeptide was lower in the appendectomy group than in the control groups (593 +/- 213 versus 1170 +/- 324 pg/ml, p less than 0.05), despite similar left atrial pressures in the two groups. The excised appendages contained approximately 30% of the total amount of atrial natriuretic polypeptide. These results demonstrate that atrial appendectomy decreases secretory function of atrial natriuretic polypeptide and reduces cardiac output in dogs with experimental high-output heart failure.

Animals↗
PubMed1991

[Clinical features of aortic dissection with early thrombosis of the false lumen].

There are cases of dissecting aortic aneurysm in which thrombotic formation occurs in the false lumen at an early stage, preventing dissection of the vessel wall and enlargement of the aneurysm. We studied such early thrombotic obliteration of false lumina in 12 (28.6%) of 42 patients with dissecting aortic aneurysm who underwent transesophageal two-dimensional echocardiography in the acute phase from June 1986 to October 1989. It was the first employment of a transesophageal approach at our hospital. In this study, we examined the clinical profiles of these patients as well as the usefulness of transesophageal two-dimensional echocardiography in establishing the diagnosis of dissecting aortic aneurysm and characterizing the disease. The patients were classified as Type I (2 patients) and Type III (10 patients; 6 Type IIIa and 4 Type IIIb) according to DeBakey's classification. The minimum and mean intervals from the onset of symptoms to transesophageal two-dimensional echocardiography were 1.5 hours and a mean of 38.2 hours, respectively. These results indicated that thrombotic obliteration of the false lumen had already occurred at a very early stage in some patients. The maximum diameter of the descending aorta was mean 37.6 mm with only 2 patients having that of 40 mm or more. Since left intrapleural hemorrhage was observed in these 2 patients (1 received emergent replacement of the descending aorta), enlargement of the aortic diameter may be indicative of unpredictable outcome, even in patients with early thrombotic obliteration of the false lumen. The long-term clinical course was favorable in all patients, including those who were treated surgically, over a mean follow-up period of 14.5 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

[Definitive myocardial blood flow evaluated by contrast echocardiography: experimental and A-C bypass flow studies].

We evaluated the feasibility of a new method for calculating definitive myocardial flow using contrast echocardiography in canine experiments and in patients who had undergone ACBG surgery. The principle for calculating flow was based on Kety-Schmidt method using time-intensity curve analysis between the epicardial and endocardial aspect. Inlet and outlet flows were hypothesized at the epicardium and endocardium, respectively. Analysis of time-contrast-intensity curves between the epicardium and endocardium, the difference of the area to the saturated point between epicardium and pericardium (A), and the saturated value (H) theoretically lead to the equation: Flow = 100 x (H/A) (Kety-Schmidt) in a 100-gram myocardium. No factors of intensity and time were included. Using this equation, the flow in 7 experimental canine and the flow of 9 patients who had ACBG surgery were compared to the electromagnetic flow. In the canine experiments, the left circumflex coronary artery was dissected free and was connected with contrast injector, a magnetic flowmeter and pneumatic occluder, proximal to distal in this order. Flow was controlled either by the occluder or drugs (papaverin and dipyridamole). Manually-agitated contrast media were injected rapidly (1 ml/2.5 sec), and M-mode echocardiographic recordings were densitometrically translated into time-intensity curves. Thirty-eight trials in 7 dogs showed close correlations (r = 0.901) between the electromagnetic flow and contrast echo flow. For the patients with ACBG, M-mode contrast echo recordings were made using transesophageal echo during the operations with contrast injections via the bypass grafts. Analysis of time-intensity curves was made and recorded in the same way as during the experiments.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Phase difference between chest flow and mouth flow during rest breathing in cases of pulmonary diseases].

The phase difference between mouth flow and chest flow in cases of pulmonary diseases measured using a body box was compared with those in normal subjects. Phase differences in chronic pulmonary emphysema (CPE) and diffuse panbronchiolitis (DPB) patients increased compared to normal subjects, but remained normal in interstitial pneumonitis patients (Normal: 3.76 +/- 1.71, CPE: 10.70 +/- 4.93, DPB: 10.81 +/- 3.15, IP: 3.83 +/- 0.15 degrees). In addition, there was a good correlation with FEV1.0, FEV1.0% and RV/TLC (r: -0.634, -0.610 and 0.803). The analysis of phase differences during rest breathing is clinically useful because it is non-effort dependent and can evaluate the degree of airway disorders.

Adult↗
PubMed1991

[Analysis of factors of increased phase differences between chest flow and mouth flow at rest breathing in patients with obstructive disorders].

The factors which increase phase differences between mouth flow and chest flow in patients with obstructive disorders were analyzed. From airway resistance, thoracic gas volume and measured chest flow, phase difference was predicted by the Runge-Kutta (R.K.) method assuming respiratory system to be a single compartment model. The ratio of the measured phase differences to the predicted value by the R.K. method in normal subjects was 0.99 +/- 0.25. These results suggest that a single compartment model can be applied to normal respiratory system. In contrast, predicted phase differences were remarkably higher than measured values in patients with obstructive disorders (CPE: 1.83 +/- 0.63, DPB: 1.50 +/- 0.48). This phenomenon could be explained by the existence of parallel inhomogeneity of alveolar pressure.

Airway Resistance↗
PubMed1991

Antifungal activity of murine polymorphonuclear neutrophils against Histoplasma capsulatum.

Murine polymorphonuclear neutrophils (PMN) were examined for fungicidal and fungistatic activity against yeast cells of Histoplasma capsulatum. In a 16-h limiting dilution assay (LDA) (constant number of PMN versus decreasing numbers of yeast cells) where PMN to yeast cell ratios were high (0.4-1.5 x 10(5):1), murine PMN exhibited a limited fungicidal effect on H. capsulatum as measured by sterilization of cultures containing one to four yeast cells. On the other hand, inoculum colony forming units (c.f.u.) of H. capsulatum were not reduced by PMN in short-term (2 h) assays (PMN to yeast cell ratio, 500:1) even though H. capsulatum stimulated a brisk oxidative burst in PMN. In the same assays 84% of Candida albicans cells were killed. These findings indicate that H. capsulatum was resistant to killing by products of the oxidative burst generated by PMN and that it was slightly sensitive to PMN in 16-h LDA assays where a different microbicidal mechanism may be operative. In long-term co-culture assays, where the PMN to yeast cell ratio was 500:1, PMN consistently inhibited the replication of H. capsulatum after 24, 48, or 72 h of incubation. Inoculum c.f.u. failed to increase significantly in co-cultures, whereas in culture medium alone c.f.u. increased several-fold in 72 h. Based on these novel findings, we speculate that PMN might play a role in resistance to H. capsulatum due to their strong fungistatic activity and to a lesser extent their limited fungicidal action.

Animals↗
PubMed1991

[Microsurgical side-to-end epididymovasostomy: surgical technique and outcomes].

The surgical procedures and results of microsurgical epididymovasostomy for obstructive azoospermia at the epididymis are reported. These procedures include the separation of a single epididymal tubule, an incision in the side wall, and a side-to-end anastomosis to the mucosa of the vas deferens under microscopic view. The tunica of the epididymis and the muscle layer of the vas are sutured together to support the mucosal anastomosis. Ten patients with epididymal obstruction underwent the side-to-end epididymovasostomy. The group consisted of two with Young's syndrome, one with an epididymal blow-out after vasectomy, one unsuccessful epididymoepididymostomy, 4 after epididymitis and 2 cases of unknown origin. After the operation, sperm appeared in 9 patients, and semen quality was normalized in 4 patients, all of whom impregnated their wives. Microsurgical side-to-end epididymovasostomy is a much easier procedure than Silber's specific tubule method, and results in a high success rate.

Adult↗
PubMed1991

[Two cases of hypersensitivity pneumonitis due to contamination of an ultrasonic humidifier].

Two cases of hypersensitivity pneumonitis due to contamination of ultrasonic-humidifier were reported. The first case, a 64-year-old man, developed fever and dyspnea on exertion in January 1986. He was hospitalized for 18 days and received antibiotics for presumptive bacterial pneumonia. Half a day after discharge, those symptoms recurred. On readmission, fine crackles were heard at the left lung base, and chest X-ray film showed ground glass shadows all over the lung fields. Bronchoalveolar lavage (BAL) and transbronchial lung biopsy (TBLB) were performed on the next day after readmission. TBLB specimen revealed lymphocyte alveolitis, granulomatous tissue and infiltration of polymorphonuclear neutrophils (PMN) in alveoli. Differential cell count of the BAL fluid showed not only lymphocytosis (38.2%) but also increased PMNs (44.2%). In the second BAL performed 18 days later, the value of PMNs demonstrated a dramatic decrease. Environmental challenge tests revealed that his hypersensitivity pneumonitis was caused by an ultrasonic humidifier in his bed room. Immunological examinations showed positive Arthus type skin reaction and serum precipitin against Aspergillus fumigatus. Inhalation challenge with A. fumigatus produced cough and dyspnea with a decrease of 10 Torr in PaO2. These data suggest that A. fumigatus may be the causative antigen in this case. The second case, a 64-year-old man who had used ultrasonic humidifier in his living room, was admitted for 8 weeks with an illness characterized by cough, low fever and general malaise on 22 January 1987. Examination revealed fine crackles on both lung bases. Chest X-ray film demonstrated diffuse nodular shadows. The TBLB specimen showed lymphocytic alveolitis and bronchiolitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Acremonium↗
PubMed1991

[Examination of the inhibitor to factor VIII in non-haemophilic patient].

We examined an inhibitor to factor VIII in non-haemophilic patient who had been developed widely spread ecchymosis and intramuscular bleeding. He had no previous personal or family history of abnormal bleeding tendency. His laboratory data was all normal except examination for blood coagulation. Coagulation studies showed prolonged activated partial thromboplastin time (48 sec) and decreased factor VIII activity (8%). The activity of the inhibitor to factor VIII was demonstrated to be 4.0 Bethesda unit. By the studies of dilution and time response curve, this inhibitor was found to inhibit up to 90% of factor VIII activity but not 100%. This inhibitor was shown to be IgG by protein-A affinity chromatography. In addition, bleeding time was prolonged in the patient. The value of von Willebrand factor antigen was 200%, but that of Ristocetin cofactor was 93%. Since the gel filtration analysis indicated that this inhibitor also suppressed Ristocetin cofactor activity, the relatively low value of Ristocetin cofactor might occur through the action of the inhibitor. These data suggest that patient's inhibitor react to factor VIII high molecular subunit.

Blood Coagulation Disorders↗
PubMed1991

[The metabolic index of nocturnal hypoxia in patients after lung resection and thoracoplasty].

The authors measured urinary uric acid (UA) and creatinine (CR), serum lactate, and CoQ10 prior to retiring at night and on awakening in the morning in 127 patients (PG) after lung resection and thoracoplasty which were done more than 20 years age for treatment of tuberculosis and in 20 controls (NC). delta UA:CR, delta lactate, and delta CoQ10 were calculated respectively as the overnight changes in urinary UA:CR and in serum lactate and CoQ10. delta UA:CR increased in PG (4.0 +/- 43.6%), whereas it decreased in NC (-22.3 +/- 17.7%) (mean +/- SD) (p less than 0.05). Nocturnal hypoxemia suggested from positive balance of delta UA:CR was seen in 37% of PG, but in only 10% of NC. delta UA:CR showed no relationship with delta lactate and delta CoQ10 and also did not correlate with the nadir of arterial oxygen saturation. PG were divided into PG with a positive balance of delta UA:CR (PG-P) and with a negative balance of delta UA:CR (PG-N). The %VC and PaO2 in the PG-P group were lower and PaCO2 was higher than in PG-N, although the difference did not achieve statistical significance.

Aged↗
PubMed1991

[Role of combined pulmonary resection during descending thoracic aortic aneurysmectomy].

Between April, 1982 and December 1990, five of 98 patients who underwent aneurysm repair for the thoracic aorta received combined resection of the descending thoracic aortic aneurysm and the lung because of marked adhesion between the aneurysm and the lung. Partial resection of the upper lobe of the lung was performed in all of five patients with auto-suture device. Three of the five patients needed no homologous blood transfusion during the surgery. Neither operative death nor pulmonary complication related to lung injury and bleeding was noticed. Our results indicate that partial resection of the lung is beneficial for avoiding intra-operative rupture of the aneurysm as well as lung injury in patients with descending thoracic aortic aneurysm severely adherent to the lung.

Aged↗
PubMed1991

Blood and brain tissue gaseous strategy for profoundly hypothermic total circulatory arrest.

Brain tissue carbon dioxide tension, pH, and oxygen tension were measured in dogs undergoing hypothermic circulatory arrest below 20 degrees C with three types of blood gas manipulation. During core cooling, dogs were given pure oxygen (group I, n = 8), 5% carbon dioxide in oxygen (group II, n = 10), or 7% carbon dioxide in oxygen (group III, n = 4). During core cooling, brain tissue carbon dioxide tension decreased significantly in group I. During circulatory arrest, carbon dioxide tension rose by 21.5 mm Hg in group I, 35.3 mm Hg in group II, and 57.0 mm Hg in group III, nearly doubling in each group. From the last 5 minutes of core cooling to the end of rewarming, carbon dioxide tension was significantly higher in groups II and III than in group I. Brain tissue pH fell by 0.33 to 0.35 during 60 minutes of circulatory arrest and did not recover in groups II and III. Brain tissue oxygen tension decreased significantly during the latter two thirds of the circulatory arrest period in all three groups. To reduce progressive tissue hypercapnia and acidosis during and after circulatory arrest, a more hyperventilatory manipulation of blood gases than that achieved by alpha-stat strategy was thought beneficial for core-cooling perfusion.

Acidosis↗
PubMed1991

[Evaluation of modern therapy for neuroblastoma].

The clinical results were evaluated periodically in 50 cases of neuroblastoma, 4 survived cases out of 15 from 1965 to 1971, 6 survived of 16 (38%) from 1972 to 1982 and 11 survived of 19 (58%) after 1983. In the early period, before 1971, our systemic wide resection was not performed. From 1972, we operated on by our wide resection's technique which based on to preserve main vessels from tumor and lymph nodes. To separate the vessels from the lymph nodes was begun from both iliaca vessels to caeliac vessels. The systemic wide resection might contribute to improve survival rate from 1972 to 1982, however, all of 7 cases in stage IV did not survive. The best result after 1983, 58% survival rate, depends on new intensive chemotherapy accompanying with autologous bone marrow transplantation. All of 3 cases in stage III and 5 of 11 cases in stage IVA survived and better survival rates. Five alive cases in stage IVA received delayed wide resection after 3 or 4 cycles of new regimen A1, and then underwent bone marrow transplantation preconditioned by Melphalan .

Child, Preschool↗
PubMed1991

[A clinical study in postoperative bile excretion of cefuzonam].

We investigated the postoperative bile excretion and serum concentration of cefuzonam (CZON) in 6 cholecystectomized patients with postsurgical biliary drainage. CZON was administered intravenously by infusion at a dose of 1.0 g immediately following the operation. Serum and bile concentrations of CZON were determined on the day of the operation and the second day after the operation. The following results were obtained. 1. Serum concentrations of CZON were at their highest levels at 30 minutes after administration of CZON. Levels were 45.8 +/- 13.8 micrograms/ml on the day of the operation and 60.9 +/- 12.2 micrograms/ml on the second postsurgical day. 2. Bile concentration peaked 1 hour after administration (4,083 +/- 1,427 micrograms/ml on the day of the operation and 4,376 +/- 630 micrograms/ml on the second postsurgical day). In particular, bile concentrations of CZON at 6 hours (259 +/- 140 micrograms/ml and 154 +/- 23 micrograms/ml) exceeded MIC80 of CZON against Gram-negative bacteria except for Pseudomonas aeruginosa. 3. Serum and bile concentrations were higher on the second postsurgical day than on the day of the operation, but the differences between these 2 days were not significant. These results have indicated that CZON is a useful drug with excellent bile excretion following cholecystectomy, and that bile concentrations of CZON are maintained at high levels for 6 hours after intravenous administration.

Adult↗
PubMed1991

[Transcatheter embolization of huge renal arteriovenous aneurysm: a case report--review of 270 cases of renal arteriovenous fistula reported in Japan].

We report a case of huge renal arteriovenous aneurysm, which was successfully treated with transcatheter arterial embolization (TAE). A 72-year-old woman was admitted with the clinical symptom of dyspnea on effort. She felt a tremor in the left abdomen. Computerized tomographic scan showed a large enhanced mass (8x7x7 cm) on the left kidney. Selective renal arteriography revealed a renal arteriovenous aneurysm. Transcatheter arterial embolization with a steel coil was performed with minimal loss of renal parenchyma. A total of 270 cases of arteriovenous fistula have been reported in Japan and were statistically analyzed. The number of reports on TAE has dramatically increased since 1978, TAE can be first indicated for treatment of renal arteriovenous fistula in view of less invasiveness and preservation of renal function.

Adolescent↗