Biomedical subjects

T Kaneda

Publications and source records attributed to T Kaneda.

At least 73 records · Page 4Linked to original sources

PubMed1998

[A case of an expanding congenital left ventricular aneurysm].

Congenital ventricular aneurysm is rare. There have been only 17 case reports in Japan. Only 9 of them were treated surgically. In this paper, we report a case with a congenital left ventricular aneurysm successfully treated by surgery. A 42-year-old female was admitted to our hospital with chest pain and ECG abnormalities. Left ventriculography revealed aneurysmal formation of the left ventricle with normal coronary arteries. Surgical resection was performed because repeated echocardiography had showed its enlargement. Surgical treatment for congenital ventricular aneurysm seems to be indicated to those with worsening symptoms, volume enlargement or thrombus formation.

Adult↗

PubMed1998

Dental bur fragments causing metal artifacts on MR images.

PURPOSE: Our purpose was to define the role of dental bur fragments in producing metal artifacts on MR images. METHODS: Dental prosthetic reconstructions were made for two dogs. The two lower second premolars were prepared for full-cast crowns by using a diamond bur. The crown margin was placed subgingivally on the right side (1 mm below the free gingival margin) and at the same level as the free gingival margin on the left side. After 1 week, full-cast crowns were cemented in place. MR imaging was performed 7 days later. RESULTS: Metal artifacts appeared in both second premolar regions of the mandible on MR images, with the right side, in which the crown margin was positioned subgingivally, displaying a larger signal distortion than the left side. After removal of the crown, the artifact remained on the right. On histopathologic examination, bur fragments were detected in the gingiva, more on the right than on the left. X-ray fluorescent element analysis showed iron in the gingival tissue containing bur fragments. CONCLUSION: Distortion of MR images was considered to be attributable in part to the damage of the gingiva and in part to the presence of dental bur fragments.

Animals↗

PubMed1997

Detection of maternofetal transfusion by placental alkaline phosphatase levels.

We investigated the volume of maternofetal transfusion by measuring placental alkaline phosphatase (PLAP) as an indicator of placental passage. PLAP levels were measured in 135 pairs of maternal-neonatal sera. Estimated volumes of maternofetal transfusion were calculated with the following formula: Volume of transfusion (in milliliters) = 85 ml/kg x BW (in kilograms) x (PLAPAB-PLAP1MO)/ PLAPMA, where BW is the birth weight, PLAPAB is the PLAP level in neonatal serum at birth, PLAP1MO is the PLAP level in neonatal serum at 1 month of age, and PLAPMA is the PLAP level in maternal serum at delivery. The mean PLAPMA, PLAPAB, and PLAP1MO levels were 276.95 +/- 159.74 IU/L, 3.83 +/- 2.17 IU/L, and 0.25 +/- 0.22 IU/L, respectively. The mean volume of maternofetal transfusion was estimated to be 3.33 +/- 1.68 ml. The mean estimated volume of maternofetal transfusion per kilogram of birth weight was significantly lower in cases of scheduled cesarean delivery (0.74 +/- 0.35 ml/kg) than in cases of vaginal delivery (1.18 +/- 0.54 ml/kg; p < 0.001) and emergency cesarean delivery (1.73 +/- 1.00 ml/kg; p < 0.01). In scheduled cesarean delivery a significant positive correlation between gestational age and the estimated volumes of transfusion per kilogram of birth weight was observed. In cases of vaginal delivery, the estimated volume of transfusion per kilogram of birth weight was significantly lower in the group with short labor (< 5 hours: 0.92 +/- 0.32 ml/kg) than in the group with prolonged labor (> or = 5 hours: 1.29 +/- 0.61 ml/kg; p < 0.001). PLAP was considered to be useful for estimating the volume of maternofetal transfusion. The transfer volume appeared to relate to uterine contractions and to histologic changes in the placenta with aging.

Adult↗

PubMed1997

Dynamics of chromosomes and microtubules visualized by multiple-wavelength fluorescence imaging in living mammalian cells: effects of mitotic inhibitors on cell cycle progression.

BACKGROUND: Mitotic events are accomplished by a coordinated interaction of molecular components within a cell. The continuous observation of specific molecular components in individual living cells provides a unique opportunity to examine the temporal and spatial coordination of these components. In order to be able to observe dynamic events in living mammalian cells, we have developed a computerized fluorescence microscope system. RESULTS: Using this fluorescence microscope system, we observed the dynamic behaviour of chromosomes and microtubules in living HeLa cells throughout an entire cell cycle. Chromosomes and microtubules were stained with Hoechst 33342 and rhodamine-conjugated tubulin, respectively. Microinjected rhodamine-tubulin was incorporated into microtubules at all stages of the cell cycle. In addition, rhodamine-tubulin stained the centrosomes during the G2 phase of the cell cycle and allowed us to observe centrosome movement. We also examined the effects of mitotic inhibitors on cell cycle progression. In a living cell treated with an inhibitor of type II DNA topoisomerase (ICRF-193) chromosomes formed an aberrant metaphase plate and failed to segregate. However, following mitotic spindle disassembly, the chromosomes decondensed normally. While the cell began to divide into two portions, cell division was eventually aborted and the daughter cells, still connected by a cytoplasmic bridge, rejoined into a single cell. These results demonstrate how a polyploid nucleus is generated in the presence of ICRF-193. On the other hand, microtubule polymerization inhibitors, such as colchicine, nocodazole and vinblastine, arrested the cell in the metaphase with condensed chromosomes; cytochalasin D did not affect the mitotic behaviour of either chromosomes or microtubules. CONCLUSIONS: Our observations of living cells demonstrate that the failure of chromosome segregation in and of itself does not prevent an exit from the metaphase, whereas the inhibition of microtubule assembly arrests cells at metaphase. Thus, a metaphase checkpoint is monitored by functional spindle microtubules but not by the completion of chromosome segregation.

Cell Cycle↗

PubMed1997

Changes in T, B, and NK lymphocyte subsets during and after normal pregnancy.

PROBLEM: Pregnancy affects the maternal immune system and the clinical course of maternal diseases. Here we report the changes in the detailed lymphocyte subsets of helper T cells, suppressor T cells, CD5+ B cells, T cell receptor (TCR) alpha beta-positive T cells (T alpha beta cells), TCR alpha beta-negative T cell (T gamma delta cells), and other during and after pregnancy through to one year postpartum, and discuss the significance of the changes. METHOD: The absolute numbers of helper T cells, suppressor T cells, cytotoxic T cells, TCR alpha beta-negative T cells (T gamma delta cells), CD5- B cells, CD5+ B cells, and NK cell subsets were examined by two-color flow cytometry in peripheral blood from 51 healthy non-pregnant women, 106 healthy pregnant women, and 148 healthy postpartum women. RESULTS: In early pregnancy, the numbers of suppressor T cells and NK cells with strong cytotoxicity (NK+3 cells) increased, and the number of cytotoxic T cells decreased. In late pregnancy, the helper T cell and NK+3 cell numbers decreased. T alpha beta, CD5- B and CD5+ B cells decreased during pregnancy. After delivery, helper T cells and cytotoxic T cells increased from 1 to 4 months postpartum, and suppressor T cells increased at 7 months postpartum. TCR alpha beta-negative T cells increased at 4 to 10 months postpartum. Both CD5- and CD5+ B cells decreased further at 1 month postpartum, but CD5+ B cells increased markedly at 7 to 10 months postpartum. CONCLUSIONS: These data indicate that 1) early increases of suppressor T cells and NK+3 cells during pregnancy may be related to the mechanism to accept or reject the fetus in early pregnancy, respectively; 2) late decreases of helper T cells and NK+3 cells may be related to the maintenance of pregnancy: 3) postpartum increases of helper T cells, cytotoxic T cells, TCR alpha beta-negative T cells (T gamma delta cells), and CD5+ B cells may be related to the postpartum aggravation of autoimmune diseases; and 4) the immunological effects of pregnancy remains until about 1 year after delivery.

Adult↗

PubMed1997

Effects of various selective phosphodiesterase inhibitors on muscle contractility in guinea pig ileal longitudinal smooth muscle.

The effects of various selective phosphodiesterase (PDE) inhibitors on muscle contractility in guinea pig ileal longitudinal smooth muscle were investigated. 1) 3-Isobutyl-1-methyl xanthine (IBMX) or zaprinast markedly inhibited the high K(+)- or carbachol (CCh)-induced contraction and increased cGMP content of the muscle strip in a concentration-dependent manner. However, these agents only slightly increased the cAMP content. Milrinone or Ro20-1724 also slightly inhibited the high K(+)- or CCh-induced contraction and increased the cAMP content, but did not increase cGMP. 2) In a fura2-loaded muscle, IBMX or zaprinast inhibited both contractions and the increase in intracellular Ca2+ ([Ca2+]i) level induced by high K+ or CCh, although the inhibitory effect on the [Ca2+]i level was smaller than that on muscle tension. 3) In alpha-toxin-permeabilized muscles, cGMP, IBMX or zaprinast significantly inhibited the Ca(2+)-induced contraction. These results suggest that IBMX and zaprinast inhibit muscle contraction in the ileal longitudinal smooth muscles mainly through an increase in cGMP and the inhibitory mechanism of IBMX or zaprinast is involved in the decreases in the [Ca2+]i level and sensitivity of contractile elements to Ca2+.

1-Methyl-3-isobutylxanthine↗

PubMed1997

Odontogenic myxofibroma arising from the periodontal ligament in the maxillary molar region.

A rare case of odontogenic myxofibroma, which arose from the periodontal ligament and expanded into the oral cavity resulting in an epulis-like lesion in a 52-year-old man, is reported including details of studies using lectin histochemistry, transmission electron microscopy (TEM), and immunohistochemistry. Most of the tumor cells, which appeared spindle-like with abundant rough endoplasmic reticulum and some microfilaments by TEM, showed immunoreactivity for mesenchymal markers. Some tumor cells, which were polygonal and contained many microfilaments and some filament bundles, were immunoreactive for muscle markers. The present case was considered to consist of many fibroblasts and some myofibroblasts.

Bicuspid↗

PubMed1997

Cell proliferation detected by DNA polymerase alpha in acute leukemias.

Fifty-nine patients with acute leukemia were studied by flow cytometry using monoclonal antibody against DNA polymerase alpha. Since fresh and frozen cells showed identical flow cytometric histograms, 86 cryopreserved samples (39 from peripheral blood and 47 from bone marrow) were used in this study. The DNA polymerase alpha-positive population ranged from 16.3 to 84.7% in peripheral blood, and from 6.5 to 92.1% in bone marrow. A positive correlation (r = 0.80; p < 0.01) was found between DNA polymerase alpha-positive populations in peripheral blood and bone marrow from the same patient. This suggests that the DNA polymerase alpha-positive population in the bone marrow can be estimated from that in peripheral blood. A negative correlation was observed between the positive population in bone marrow samples and the time to reach a nadir (r = -0.58: p < 0.01), while a positive correlation was found between the tumor cell count in bone marrow and the DNA polymerase alpha-positive population (r = 0.64; p < 0.01) in patients who responded to chemotherapy.

Acute Disease↗

PubMed1996

Cefaclor concentration in pus from abscess caused by odontogenic infection after a single oral administration.

1. Cefaclor concentrations in serum and pus from abscess of odontogenic infection after a single oral administration of 500-mg cefaclor were assayed and pus concentrations were compared with minimum inhibitory concentration (MIC) of oral streptococci isolated from odontogenic infection. 2. The mean peak concentrations in serum and pus were found at identical times, 1.5 hr after administration, which were 7.22 and 0.72 micrograms/ml, respectively. 3. The mean ratio of pus:serum concentration at the peak time was 0.10. 4. Most cefaclor concentrations in pus at the peak time (seven of nine cases) exceeded the MIC for 90% of oral streptococci (0.5 micrograms/ml).

Administration, Oral↗

PubMed1996

Magnetic resonance appearance of bone marrow in the mandible at different ages.

To differentiate pathologic states of bone marrow from normal age-related marrow conversion, magnetic resonance appearances of the mandible were analyzed cross-sectionally according to age in 73 normal volunteers. Low signal intensities of red marrow first changed to high signal intensities in the anterior region of the mandibular body. With increase in age, marrow conversion was observed in the premolar/molar region, angle, ramus, and condyle regions in that order. No red marrow was recognized in the body of the mandible of subjects more than 30 years old. After the age of 30, the majority of the subjects showed high signal intensities in the entire bone marrow of the mandible. However, one subject over 30 years of age showed some portions of red marrow in the ramus and condyle. This knowledge about age-related marrow conversion of the mandible on magnetic resonance imaging will be useful in the visual differentiation from abnormal bone marrow, such as anemias, inflammatory diseases, infiltrative neoplastic disorders, and metastatic diseases.

Adolescent↗

PubMed1996

Partial monosomy 10q and partial trisomy 9q with anal atresia due to maternal translocation: t(9;10)(q32;q26).

We report a case of a boy with a partial deletion of the long arm of chromosome 10 and partial duplication of the long arm of chromosome 9 due to maternal balanced translocation. The karyotype was 46,XY,-10, +der(10)t(9;10)(q32;q26)mat. Our patient had imperforate anus and as this finding is usually not observed in association with trisomy 9q, it suggests that partial monosomy of the long arm of chromosome 10 might be associated with anogenital anomalies.

Abnormalities, Multiple↗

PubMed1996

Cystic lesions of the maxillomandibular region: MR imaging distinction of odontogenic keratocysts and ameloblastomas from other cysts.

OBJECTIVE: Differentiating odontogenic keratocysts and ameloblastomas from other cystic lesions in the maxillomandibular region is important because of their high recurrence rates. Conventional radiography, CT, and fine-needle aspiration biopsy are limited for differential diagnosis. The purpose of this study was to review the MR findings in patients with odontogenic keratocysts, ameloblastomas, and other maxillomandibular cysts to determine the value of MR imaging in the differential diagnosis of these lesions. SUBJECTS AND METHODS: MR images were obtained in 38 patients with 43 cystic lesions of the maxillomandibular region. All the lesions (19 odontogenic keratocysts, 11 ameloblastomas, five primordial cysts, five radicular cysts, and three cysts of other types) were pathologically confirmed by surgery or biopsy. Contrast-enhanced MR studies were performed in 34 patients. Images were reviewed to determine various imaging parameters: locularity, solid or cystic pattern, thickness and contrast enhancement of the walls, and homogeneity and signal intensities of the fluids. T2 relaxation times of cystic components were calculated in 31 lesions. RESULTS: MR images of odontogenic keratocysts showed that the cyst were unilocular in 10 lesions and multilocular in nine. In 10 lesions the cysts wall was uniformly thin and had poor contrast enhancement. Seven cysts had thick walls and two had no definite walls. In 17 lesions, the cystic contents showed heterogeneous signal intensity on T1-weighted images, T2-weighted images, or both. Eight cysts had predominantly intermediate or high T1-weighted signal intensity, and six cysts had predominantly intermediate T2-weighted signal intensity. MR findings in ameloblastomas were different from those in odontogenic keratocysts: a mixed solid and cystic pattern (11 lesions), irregularly thick walls (11 lesions), papillary projections (seven lesions), and strong enhancement of solid components (nine lesions). T2 relaxation times of cystic components were significantly shorter in odontogenic keratocysts than in ameloblastomas, with no overlap. All other cysts showed a unilocular, purely cystic pattern, with homogeneous fluids, although the T2 relaxation times of four lesions overlapped those of odontogenic keratocysts. CONCLUSION: From the MR findings of the walls, solid components, and the fluid contents, odontogenic keratocysts could be differentiated from ameloblastomas in all cases, although some other cysts showed MR findings similar to those of odontogenic keratocysts.

Adolescent↗

PubMed1996

MR of the submandibular gland: normal and pathologic states.

PURPOSE: To evaluate the MR appearance of normal and pathologic states of the submandibular gland. METHODS: MR images of 22 healthy subjects and 21 patients with histopathologically confirmed disorders of the submandibular gland (five pleomorphic adenomas, two hemangiomas, two malignant lymphomas, one adenoid cystic carcinoma, one squamous cell carcinoma, and 10 cases of sialadenitis) were reviewed. RESULTS: All normal submandibular glands showed higher signal intensity than surrounding muscle but lower intensity than fat on T1-weighted and T2-weighted images. Postcontrast images showed moderate enhancement of the gland. All the tumors had lower signal intensity than the normal submandibular gland on T1-weighted images and had intermediate to high (n = 8) or high (n = 3) signal intensity relative to the normal submandibular gland on T2-weighted images. Six of seven benign tumors were well defined, and three of four malignant tumors were poorly defined. In all cases of sialadenitis, the submandibular gland showed diffusely different signal intensities from the normal gland on both T1-weighted and T2-weighted images. Eight cases of chronic sialadenitis showed lower T2-weighted signal intensities than the normal gland, and this can be explained histopathologically by marked fibrosis and cellular infiltration. CONCLUSIONS: MR imaging can show the presence, extent, margins, and signal intensity changes of pathologic conditions of the submandibular gland.

Adenoma, Pleomorphic↗

PubMed1996

[Genetic diagnosis of pelvic lymph node metastasis using fine needle aspiration samples in prostate cancer].

We have developed a highly sensitive method to detect pelvic lymph node metastasis using the reverse transcriptase-polymerase chain reaction (RT-PCR) with primers specific for prostate-specific antigen (PSA) gene. Fine needle aspiration biopsy (FNAB) of pelvic lymph nodes was performed in 24 patients with prostate cancer. Each aspirated sample (0.05-0.1 ml) was divided into 2 parts; one for RNA extraction and RT-PCR to detect the fragment of PSA mRNA, and the other to smear on a slide glass for conventional cytology. The PSA gene was detected by RT-PCR in 11 FNAB samples which included not only all 6 cytologically positive and 2 cytologically class III cases but also 3 of 16 cytologically negative cases. The PSA gene was not detected by RT-PCR of FNAB samples in any of the 20 cases of bladder cancer. Thus RT-PCR for detection of the PSA gene in FNAB samples may be useful as a new diagnostic technique for detection of early lymph node metastasis in prostate cancer and an additional tool for cytological diagnosis of prostate cancer.

Aged↗

PubMed1996

[Genetic diagnosis of pelvic lymph node metastasis in prostate cancer using aspiration biopsy samples].

We have developed a highly sensitive method to detect pelvic lymph node(LN) metastasis using reverse transcriptase-polymerase chain reaction(RT-PCR) with the primers specific for prostate-specific antigen(PSA) gene in combination with the fine needle aspiration biopsy(FNAB). The specimens were obtained from pelvic LN from 15 prostate cancer patients and 15 bladder cancer patients. The aspirated samples (0.05 approximately 0.1 ml) were used for detecting the fragment of PSA mRNA by RT-PCR and Southern blot analysis, and the rest of samples were submitted to conventional cytology. Expression of PSA gene was detected in 9 cases of FNAB samples including all 5 cytologically positive and further more 2 cytologically class III cases, and 2 of 8 cytologically negative cases. RT-PCR of FNAB samples from all cases of bladder cancer were negative for the detection of PSA gene. The sensitivity of PSA gene by RT-PCR was very high and could detect 10 degrees cancer cell. In conclusion, our study suggested that RT-PCR for detection of PSA gene in FNAB samples might become a new diagnostic tool for detection of small foci of prostatic cancer metastasis in LN and combination use of RT-PCR and cytology could greatly contribute to accuracy in diagnosis.

Aged↗

PubMed1995

Chemiluminescence detection of mono-, bis-, and tris-hydroperoxy triacylglycerols present in vegetable oils.

A reliable method was needed to analyze molecular species of oxidized vegetable oils. In order to accomplish this goal, mono-, bis-, and tris-hydroperoxides (Mono-OOH, Bis-OOH, and Tris-OOH, respectively) of triacylglycerols formed during autoxidation and photosensitized oxidation of oils were determined by reversed-phase high-performance liquid chromatography in combination with chemiluminescence detection (CL-HPLC). Mono-OOH was the major species (96% of total hydroperoxides) in trioleoylglycerol [peroxide value (PV) 0.16 meg/kg], and Bis-OOH and Tris-OOH showed prolonged accumulation with photooxidation. This profile was confirmed in photooxidation of trilinoleoylglycerol and trilinoleoylglycerol. Soybean oil (PV 6 meq/kg) contained Mono-OOH oleoyl-linoleoylglycerol as the main peroxidic molecular species (50% of total hydroperoxides). Mono-OOH trilinoleoylglycerol was the principal species (61% of total hydroperoxides) in safflower oil (PV 5 meq/kg), and Mono-OOH oleoyl-oleoyl-linoleoylglycerol was the representative species (66% of total hydroperoxides) in olive oil (PV 3 meq/kg). The CL-HPLC method, which is specific for the detection of hydroperoxides, should prove useful in studies of triacylglycerol oxidation in foods and vegetable oils.

Chromatography, High Pressure Liquid↗

PubMed1995

Magnetic resonance imaging of osteomyelitis in the mandible. Comparative study with other radiologic modalities.

Magnetic resonance imaging of 14 histopathologically confirmed cases of osteomyelitis of the mandible was retrospectively reviewed. The findings of magnetic resonance imaging were compared with conventional radiography, computed tomography, bone scintigraphy, and histopathologic examinations. All lesions in bone marrow were shown as areas of low (64%) or low-to-intermediate (36%) signal intensity on T1-weighted images, and areas of high (29%), mixed (high and low, 21%; high and intermediate, 36%) or low (14%) signal intensity on T2-weighted images. Histopathologically, high T2-weighted signal intensity areas that showed enhancement after contrast injection corresponded to active infection. These were not collections of pus but were predominantly areas of granulation tissue. Magnetic resonance imaging showed larger areas of abnormality than plain radiography or computed tomography. Bone scintigraphy did not accurately reveal the locations of lesions but showed heterogeneous increased uptake in all patients. MRI was an extremely useful technique for assessing osteomyelitis of the mandible.

Acute Disease↗

PubMed1995

Cardiovascular effects of intracerebroventricularly administered growth hormone-releasing factor in spontaneously hypertensive rat.

1. We investigated the cardiovascular effects of intracerebroventricularly administered (ICV) growth hormone-releasing factor (GRF) in both spontaneously hypertensive rats (SHR) and Wistar rats (WR) with reference to the involvement of adrenergic mechanisms and plasma AVP concentration. 2. The ICV GRF induced biphasic changes of mean arterial pressure (MAP) in SHR. In the first phase, maximum pressor response was observed 2-3 min after injection. In the second phase, maximum depressor response was observed 12-13 min after injection, and lasted up to 21-22 min. In WR, there were no significant changes in MAP. 3. ICV phentolamine attenuated the GRF-induced pressor response, but did not affect the depressor response. ICV bunazosine had no effect in both responses. ICV yohimbine attenuated the GRF-induced pressor response, but did not affect the depressor response. 4. In SHR, plasma AVP concentration was not affected by ICV GRF. 5. These data suggest that central GRF plays an important role in the maintenance of hypertension in SHR, since ICV GRF caused a significant depressor effect in SHR but not in WR. ICV GRF induced biphasic changes of MAP in SHR. The pressor response was mediated through central alpha2-adrenoceptors. The depressor response was not mediated through central alpha-adrenoceptors. The depressor effect of ICV GRF was not mediated by the changes of plasma AVP concentration.

Animals↗