Search PubMed⌕ Search

Biomedical subjects

M Kajiyama

Publications and source records attributed to M Kajiyama.

At least 19 recordsLinked to original sources
PubMed2003

[Minimally invasive video-assisted thoracic surgery using radially expanding trocars].

We report a new and safer access device for thoracoscopic operation. This radially expanding trocar provides a smaller incision of skin and a lesser visceral, vascular or neural injury than a conventional cannula. Therefore, most of patients undergoing this operation do not feel much pain. Moreover, this device system is more cost effective than a conventional one. We prefer and recommend this minimally invasive technique for video-assisted thoracic surgery.

Equipment Design↗
PubMed2002

Actual behaviour of N-butyl-2-cyanoacrylate (histoacryl) in a blood vessel: a model of the varix.

BACKGROUND AND STUDY AIMS: Though many gastric varices are treated endoscopically with n-butyl-2-cyanoacrylate, its behavior in varices is not known precisely. MATERIALS AND METHODS: We created a varix model. A volume of 0.7 ml or 1.4 ml of 71.4 % n-butyl-2-cyanoacrylate, a tissue adhesive, was injected into vinyl tubes of 0.4, 0.6, 0.9, and 1.2 cm in diameter, which were filled with still blood or flowing blood. The tissue adhesive was also injected into the inferior vena cava or femoral vein of dogs. RESULTS: N-butyl-2-cyanoacrylate was similarly polymerized in the vinyl tubes and the animal veins. A volume of 0.7 ml of the tissue adhesive could block all tubes up to 0.6 cm in diameter. A double quantity of the tissue adhesive could block tubes 0.9 and 1.2 cm in diameter, with flow velocities up to 10 cm/s and up to 5 cm/s, respectively. Some polymer masses were fragmented. CONCLUSIONS: One rapid shot of the tissue adhesive can block a vessel 0.6 cm or less in diameter with fast flow velocity, and a vessel up to 1.2 cm in diameter with slow flow velocity. Fast blood flows in a larger diameter vessel and slow injection of the tissue adhesive may result in fragmentation. This model of the varix was useful for assessing the effect of tissue adhesive used to treat gastric varices.

Animals↗
PubMed2001

Purification and characterization of poly(aspartic acid) hydrolase from Sphingomonas sp. KT-1.

Poly(aspartic acid) (PAA) hydrolase was purified from Sphingomonas sp. KT-1 (JCM10459). The purified hydrolase degraded thermally synthesized PAA to oligomers. The molecular mass of PAA hydrolase was 30 kDa and the isoelectric point was 8.9. The optimum values of pH and temperature for PAA degradation were 10.0 and 40 degrees C, respectively. The investigation of the effect of inhibitors for the PAA-degrading activities has revealed that the PAA hydrolase is a serine-type hydrolase. The structural analysis of PAA-degraded products using (1)H and (13)C nuclear magnetic resonances has indicated that the purified enzyme hydrolyzes selectively the beta-amide linkage connecting with beta-aspartic acid units in PAA.

Hydrogen-Ion Concentration↗
PubMed2001

Familial gastrointestinal stromal tumor with hyperpigmentation: association with a germline mutation of the c-kit gene.

We describe 2 siblings with multiple gastrointestinal stromal tumors (GISTs) and cutaneous hyperpigmentation. Both had a point mutation of the c-kit gene. The patients were sisters who had exhibited cutaneous hyperpigmentation since their late teens, but the diagnosis of multiple gastrointestinal submucosal tumors was not made until they were 41 and 45 years old. Histologic examination showed that these tumors were GISTs expressing CD34 and Kit protein. Both patients died of GISTs. Single-strand conformation polymorphism analysis showed a mutation of c-kit in tumor DNA extracted from paraffin-embedded specimens. Direct sequencing analysis showed that the point mutation occurred at codon 559 of exon 11 (Val-->Ala). The same single-point mutation was detected in DNA extracted from peripheral leukocytes obtained from the younger sister and her 2 children (who had similar general hyperpigmentation) as well as in DNA from a skin biopsy specimen taken from the older sister. The germline mutation at codon 559 of the c-kit gene found in the present familial GISTs differed from that in a previously reported case of familial GISTs. We propose that GISTs caused by a germline mutation of the c-kit gene should be referred to as GIST-cutaneous hyperpigmentation disease.

Adult↗
PubMed2000

Successful zonisamide treatment for infants with hypsarrhythmia.

We determined that zonisamide was effective in three epileptic infants with hypsarrhythmia. Two patients had the electroencephalographic pattern of hypsarrhythmia associated with developmental delay but lacked the characteristic tonic spasms. A third patient exhibited the typical triad of infantile spasms but had a poor general condition requiring controlled ventilation. We therefore chose zonisamide instead of adrenocorticotropin for these patients. Our data suggest that zonisamide may be a useful treatment in patients falling short of the diagnostic triad of infantile spasms or complicated by a poor overall medical condition.

Anticonvulsants↗
PubMed2000

Suppression of cardiac sympathetic nervous system during dental surgery in hypertensive patients.

We determined the changes in blood pressure, pulse rate, and heart rate variability during dental surgery in hypertensive patients. The study included 18 essential hypertensives and 18 age and sex matched normotensive controls who underwent tooth extraction at our hospital. Holter electrocardiographic monitoring was used to determine the power spectrum of R-R variability before and during dental surgery. The low frequency (LF: 0.041 to 0.140 Hz), high frequency (HF: 0.140 to 0.500 Hz), and total spectral powers (TF: 0.000 to 4.000 Hz) were calculated, and the ratio of LF to HF and the percentage of HF relative to TF (%HF: HF/TF x 100) were used as indexes of sympathetic and parasympathetic activities, respectively. The baseline blood pressure for hypertensive patients (149 +/- 4/85 +/- 2 mmHg) was significantly higher than that for normotensive patients (119 +/- 3/71 +/- 2 mmHg). The baseline pulse rates were similar between the two groups. Blood pressure increased during tooth extraction in both groups; however, changes in blood pressure did not differ between them. Administration of local anesthetic significantly decreased the %HF in normotensive patients (before vs. after anesthesia; 22.3 +/- 2.4 vs. 13.8 +/- 2.7%, p < 0.05). In contrast, the LF/HF significantly decreased during the local anesthesia and tooth extraction in hypertensive patients. These results suggest that pressor response induced by tooth extraction did not differ between normotensive and hypertensive patients, and that suppression of the cardiac sympathetic nervous system during dental surgery might attenuate the pressor response in patients with hypertension.

Adult↗
PubMed1999

Hepatitis G virus infection in a high-risk subgroup of hospitalized dental patients.

OBJECTIVE: The prevalence of hepatitis G virus infection was evaluated in dental patients whose clinical laboratory test results were positive for hepatitis C virus antibody, hepatitis B virus surface antigen, or elevated serum alanine transaminase concentrations. STUDY DESIGN: Frozen serum samples from patients with hepatitis C virus antibody (n = 63), hepatitis B virus surface antigen (n = 20), or alanine transaminase concentrations greater than 100 IU (n = 14) were assessed for GB virus C (GBV-C)/hepatitis G virus RNA by a reverse transcriptase-polymerase chain reaction. RESULTS: Six of 63 patients with hepatitis C virus antibodies had serum hepatitis G virus RNA (9.5%), and 2 of 20 subjects with hepatitis B virus surface antigen had hepatitis G virus RNA (10.0%). None of 14 patients whose alanine transaminase concentration was greater than 100 IU/L had hepatitis G virus RNA. Of 4 subjects with both hepatitis C virus antibody and hepatitis B virus surface antigen, 2 had hepatitis G virus RNA (50%). In the total study population (N = 92), 6 subjects (6.5%) had hepatitis G virus RNA. All hepatitis G virus-infected patients also had hepatitis C virus antibody. Neither serum alanine transaminase nor aspartate transaminase concentrations were different between subjects with and subjects without hepatitis G virus RNA. The lack of a relationship between hepatitis G virus infection and elevation of alanine transaminase and aspartate transaminase might suggest that this virus is not truly a hepatitis virus. CONCLUSIONS: Hospitalized dental patients are infected with hepatitis G virus at a prevalence similar to or slightly higher than that seen in the general population. Dentists should pay close attention to infection control with respect to the potential new hepatitis virus known as hepatitis G virus.

Adolescent↗
PubMed1999

The expression of proliferating cell nuclear antigen (PCNA) and p 53 protein correlate with prognosis of patients with oral squamous cell carcinoma.

Few Data are available regarding expression of proliferating cell nuclear antigen (PCNA) versus overexpression of p 53 protein and prognosis for oral squamous cell carcinoma (O-SCC). This study evaluated the relationship between expression of PCNA and p 53 protein and certain clinical and pathologic parameters to prognosis in O-SCC. Scattered PCNA immunoreactive cells were found in 50 of 51 (98.0%) tumors. The mean PCNA-labelling index (PCNA-LI) of O-SCC was 34.7 +/- 12.0% (n = 50). The PCNA-LI was significantly high in O-SCC when compared to normal squamous epithelium (3.9 +/- 2.1%, n = 10). Altogether, 28 of 51 (54.9%) tumors showed nuclear immunoreactive for the p 53 protein. p 53-positive nuclei were clearly stained as granular or reticular in O-SCC. Microscopically, it appeared that the staining patterns of PCNA- and p 53-positive cells were quite similar. The mean value of PCNA-LI for the p 53-positive cases was 37.9 +/- 11.9% (n = 28), which was significantly higher than the 30.8 +/- 11.1% of the 23 negative cases. The survival rates at 3-year and 5-year for patients with p 53-negative O-SCC were 78.3% and 73.4%, respectively, while those for patients with p 53-positive O-SCC were 51.9% and 43.2%, respectively. No significant correlation could be found between PCNA-LI and T classification, N classification and Stage classification. The expression of p 53 was detected in 48.5% (16/33) of cases without regional lymph node metastasis, and 66.7% (12/18) with regional lymph node metastasis. There was a significant difference between PCNA-LI and p 53-positive cases, and prognosis. In PCNA-LI, the Grade 4 by mode of invasion was significantly higher than Grade 1, 2 and 3. The PCNA-LI and p 53-positive cases were significantly correlated with histological grading of malignancy. The present study shows a relationship between PCNA and p 53 protein. It also suggests that both PCNA and p 53 positive rates are the malignant potential of the O-SCC.

Adult↗
PubMed1998

[Combined rupture of trachea and esophagus following blunt trauma--a case report].

A 49-year-old man was involved in a motor vehicle crash and was admitted to a local hospital. The following day, he was transferred to our hospital because of worsening dyspnea. Initial examination revealed no subcutaneous emphysema, and chest computed tomography (CT) demonstrated no mediastinal air. A left thoracentesis tube was placed for pneumothorax, which reduced the patient's respiratory distress. He had a persistent, productive cough, which worsened when he drank water. A repeat chest CT on the fifth hospital day revealed a tracheo-esophageal fistula. Bronchoscopy and esophagoscopy confirmed the diagnosis. He underwent repair of the trachea and esophagus. The ruptured membraneous portion of the trachea was closed with interrupted sutures and covered with pedicled pericardial flap. The perforated anterior esophageal wall was sutured in layers and reinforced with a fifth intercostal muscle flap. A gastrostomy tuve was placed for feeding access. Within 6 weeks, the patient recovered completely.

Esophagus↗
PubMed1998

Changes in blood pressure and heart rate variability during dental surgery.

The objective of the present study was to determine the changes in blood pressure, pulse rate, and heart rate variability during dental surgery. The study included 40 patients, 19 to 74 years of age (mean age: 42.7+/-3.0 years), who underwent tooth extraction at our hospital. Holter electrocardiographic monitoring was used to determine the power spectrum of R-R variability before and during dental surgery. The low frequency (LF: 0.041 to 0.140 Hz), high frequency (HF: 0.140 to 0.500 Hz), and total spectral powers (TF; 0.000 to 4.000 Hz) were calculated, and the ratio of LF to HF and percentage of HF relative to TF (%HF: HF/TF x 100) were used as indices of sympathetic and parasympathetic activities, respectively. The baseline blood pressure and pulse rate were 121+/-3/70+/-2 mm Hg and 70+/-1 beats/min, respectively. After the administration of local anesthetic (2% lidocaine) containing 1:80,000 epinephrine, both the blood pressure and pulse rate increased. During dental surgery, blood pressure increased further to 132+/-3/73+/-2 mm Hg. The increase in blood pressure was greater in middle-aged and older patients (> or =40 years old). In young patients (<40 years old), the %HF decreased and the LF/HF increased during local anesthesia. In contrast, in middle-aged and older patients, the LF/HF decreased during local anesthesia. These results suggest 1) that middle-aged and older patients have a greater increase in blood pressure during dental surgery than younger patients, and 2) that the regulation of the autonomic nervous system during dental surgery differs between younger and older patients.

Adult↗
PubMed1998

Primary localization amyloidosis of the sublingual gland.

We here in present a very rare case of primary localized amyloidosis with amyloid A protein of the sublingual gland. It presented a tumorous appearance on the left oral floor. Pretreatment with potassium premanganate made biopsy specimens unstained by Congo red. Immunohistochemical staining for AA protein was positive. Systemic amyloidosis was ruled out based on clinical and laboratory examinations. The gastric and the labial salivary glands biopsy showed no amyloid deposits. As far as we know, this is the first case of primary localized amyloidosis with amyloid A protein of the oral cavity, and tumor-formed amyloidosis of the sublingual gland.

Amyloidosis↗
PubMed1998

Histological grading of malignancy correlates with regional lymph node metastasis and survival of patients with oral squamous cell carcinoma.

This study evaluated the effectiveness of certain clinical and pathologic parameters in prognosing in oral squamous cell carcinoma (O-SCC). Patients and Methods. We performed a univariate and multivariate analysis of 212 patients with O-SCC and thus determined the move valuable factors in making a prognosis. We then investigated the relationships among the various pathologic parameters and regional lymph node metastasis. Regarding the pathologic parameters, a multivariate analysis using Cox's proportional hazard model determined inflammatory infiltration, invasive tendency, necrotic tendency, mitotic figures, and vascular permeation to be significant and independent prognostic factors affecting O-SCC. In addition, such the pathologic parameters as the mode of invasion, cellular atypia, mitotic figures, a necrotic tendency and as invasive tendency all correlated with the occurrence of regional lymph node metastasis. These statistically estimated histological grading of malignancy was thus found to be clinically acceptable and useful in helping to make a prognosis of O-SCC patients.

Adult↗
PubMed1998

Estimation of tumor necrosis factor-alpha in the diagnosis, the prognosis and the treatment follow-up of oral squamous cell carcinoma.

This study evaluated usefulness of serum tumor necrosis factor-alpha (TNF-alpha) levels in the diagnosis and prognosis of oral squamous cell carcinoma (O-SCC). We performed a clinico-pathological estimation of 38 patients with O-SCC and determined the more valuable factors in making a prognosis. The mean serum concentration of TNF-alpha for the patients with O-SCC (14.13 +/- 13.17 pg/ml) was significantly higher (p < 0.05) than that of the healthy controls (3.49 +/- 2.97 pg/ml). The mean serum concentrations of TNF-alpha were significantly higher (p < 0.05) in the good-prognosis group (16.73 +/- 18.64 pg/ml) than in the poor-prognosis group (9.62 +/- 5.92 pg/ml). The survival curve revealed a better prognosis for patients with serum TNF-alpha-positive than for patients with serum TNF-alpha negative. There was a significant correlation (p < 0.05) with serum TNF-alpha levels and two tumor markers (SCCA, IAP). These results of the present study suggest that a evaluation of serum TNF-alpha levels in O-SCC is a valuable tool as a tumor marker for the diagnosis, prognosis and treatment monitoring of O-SCC.

Adult↗
PubMed1998

Manganese superoxide dismutase (Mn-SOD) correlates with prognosis of patients with oral squamous cell carcinoma.

In the present study, tissue manganese superoxide dismutase (Mn-SOD) activities were determined postoperatively as a means to gauge future prognosis in oral squamous cell carcinoma (O-SCC). We investigated the relationships among the various clinico-pathologic parameters and clinical course of 43 patients with O-SCC. The Mn-SOD activity in the cancerous tissues decreased with the healthy controls, but there was no significant difference between the patients with O-SCC and healty controls. There was no significant difference between tissue Mn-SOD activities and clinical stage. However, patients who presented metastatic lymph nodes (N 1 or N 2) exhibited higher tissue Mn-SOD activities than patients without metastatic lymph nodes. In the pathologic parameters, the tissue Mn-SOD activities of grade 4 C, 4 D group and high histological malignancy group were significant higher than those of other groups. The tissue Mn-SOD activities were significantly lower in the good-prognosis group than in the poor-prognosis group. These results of the present study suggest that a evaluation of tissue Mn-SOD activities in O-SCC is a useful prognostic factor for screening of patients with O-SCC.

Adult↗
PubMed1997

Keratinocytes become terminally differentiated in a process involving programmed cell death.

Oral keratinocytes originate from basal cells, differentiate during migration to the surface, and finally are shed. Apoptosis occurs at the end of differentiation, but the precise relationship between terminal differentiation and apoptosis is not clear. In the present study, Bcl-xL was expressed in the basal cell and spinous cell layers, and Bax was expressed in the spinous cell and granular cell layers. In cultured keratinocytes, Bcl-xL was expressed under conditions of 0.1 mM calcium (low Ca2+) but disappeared under conditions of 1.0 mM calcium (high Ca2+); the latter induces keratinocyte differentiation. Bax was not expressed in keratinocytes with low Ca2+ but was expressed in cells with high Ca2+. Finally keratinocytes with high Ca2+ underwent apoptosis, which was detected by the TUNEL method and by 180-bp DNA fragmentation. These results suggest that the process of terminal differentiation in gingival epithelium is a pathway to apoptosis.

Apoptosis↗
PubMed1997

Combination assay for tumor markers in oral squamous cell carcinoma.

PURPOSE: This study evaluated use of a combination assay of tumor markers in the diagnosis of oral squamous cell carcinoma. PATIENTS AND METHODS: Serum levels of four tumor markers (carcinoembryonic antigen [CEA], squamous cell carcinoma antigen [SCCA], immunosuppressive acidic protein [IAP], and cytokeratin 19 fragment [Cyfra]) were simultaneously measured in 42 patients with oral squamous cell carcinoma (O-SCC) and in 12 patients with oral benign diseases. RESULTS: The positive rates were 31.0% for CEA, 38.1% for SCCA, 52.4% for IAP, and 38.1% for Cyfra in patients with O-SCC. These rates were significantly different (P < .01) from those of control patients with oral benign diseases. The sensitivity (81.0%) and accuracy (77.8%) of the combination assay uses higher than that obtained with individual markers. CONCLUSION: A combination assay with CEA, SCCA, IAP, and Cyfra may be useful for the screening of patients with suspected oral squamous cell carcinoma.

Adult↗
PubMed1997

Copper concentration in hyperintense hepatocellular carcinomas of Long-Evans cinnamon rats on T1-weighted images.

The Long-Evans Cinnamon (LEC) rat has abnormal intrahepatic copper accumulation and spontaneously develops hepatocellular carcinomas following hereditary hepatitis. The hepatocellular carcinomas are very similar to human well-differentiated hepatocellular carcinoma in histopathological features and on MR images. Copper is believed to be one of the causes of hyperintensity of hepatocellular carcinomas compared to surrounding non-cancerous tissues on T1-weighted MR image. Eight LEC rats were studied by MR imaging. We measured copper concentrations from the hepatocellular carcinomas and surrounding non-cancerous liver tissues. Signal intensity of hepatocellular carcinomas without cystic areas was iso- to slightly hyperintense relative to surrounding non-cancerous tissues on T1-weighted images. Histopathologically, most of the tumors resembled human highly or well-differentiated hepatocellular carcinomas. Copper concentrations of the hepatocellular carcinomas were lower than the surrounding non-cancerous liver tissues. Copper may not be the cause of increased signal intensity typically observed on T1-weighted images of hepatocellular carcinomas.

Animals↗