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Biomedical subjects

A Yamauchi

Publications and source records attributed to A Yamauchi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Spontaneous rupture of a parathyroid adenoma presenting as a massive cervical hemorrhage: report of a case.

We report an unusual case of spontaneous rupture of a parathyroid adenoma causing cervical hemorrhage. A 60-year-old woman presented to our hospital after the sudden development of extensive ecchymosis of her neck and upper anterior chest wall. Computed tomography (CT) scanning revealed a hematoma in the left retrotracheal space, and laboratory examinations revealed significant hypercalcemia, hypophosphatemia, and a high level of intact parathyroid hormone. Primary hyperparathyroidism was diagnosed, but it was not until the hematoma had subsided, 4 months after her initial presentation, that a parathyroid adenoma was revealed by CT. An operation was performed, and a parathyroid adenoma with hemosiderin deposition was histologically diagnosed. Although this phenomenon is unusual, all endocrine surgeons should be well aware of the possibility of its occurrence.

Adenoma↗
PubMed2001

Monitoring of facial evoked EMG for hemifacial spasm: a critical analysis of its prognostic value.

Microvascular decompression (MVD) has come to stay as an effective way of treating hemifacial spasm. But it remains to be seen how much each of the electrophysiological monitoring techniques (intra-operative) are contributing to its increased efficacy. Their role as indicators for re-exploration or recurrence is to be evaluated with more studies. We have used the lateral spread response in those patients who had distinctly abnormal recording on the ipsilateral side, studied the intra-operative changes during MVD and correlated with the outcome of surgery. 38 patients operated for HFS, were selected for intra-operative monitoring of abnormal muscle responses. In 17 patients, there was persistence of abnormal muscle responses in the immediate postoperative period and only 6 of them had mild HFS. Two of 21 patients who had disappearance of abnormal responses had persistent mild HFS; but in all cases, the HFS disappeared within 3 months. So we found that the intra-operative recording was really not reliable in predicting the immediate postoperative outcome. However the outcome at 3 months suggested that waiting for some time before re-exploration is a better option, especially if the HFS had become mild.

Adult↗
PubMed2001

E-cadherin expression associated with differentiation and prognosis in patients with non-small cell lung cancer.

BACKGROUND: E-Cadherin plays a major role in maintaining the intercellular junctions in epithelial tissues. The reduction of E-cadherin expression in cancer cells may be associated with tumor differentiation, metastasis, and a poor prognosis. METHODS: Immunohistochemistry for E-cadherin expression was performed on 109 tumors from patients with non-small cell lung cancer who underwent operations. RESULTS: With respect to membranous immunostaining, 57 carcinomas were E-cadherin-positive, 39 carcinomas E-cadherin-reduced, and 13 carcinomas E-cadherin-negative. The percentage of poorly differentiated tumors in the impaired E-cadherin expression group was significantly higher than that in the E-cadherin-positive group (p = 0.005). Furthermore, the frequency of lymph node metastases in tumors with impaired E-cadherin expression was significantly higher than that in the E-cadherin-positive tumors (p = 0.011). A Cox regression analysis revealed that E-cadherin expression was a significant factor in the prediction of survival for patients with non-small cell lung cancer (p = 0.002). CONCLUSIONS: E-Cadherin expression was associated with tumor differentiation, lymph node metastasis, and prognosis in patients with non-small cell lung cancer.

Cadherins↗
PubMed2001

Clonal evolution of gastric lymphoma of mucosa-associated lymphoid tissue type.

Development of multiple lesions is frequent in gastric lymphoma of mucosa-associated lymphoid tissue (MALT) type. Presence of clonal components in multiple lesions was examined on the resected samples from 18 cases by using PCR-based method for immunoglobulin heavy-chain gene rearrangement. There were two or more lesions in 10 cases, and 2 to 12 samples were obtained from each lesion. The remaining eight cases had a single large lesion, from which two to six samples were collected from separate areas from each other. A total of 86 samples were analyzed. Histologic findings in each sample were categorized as follows: proliferation of exclusively centrocyte-like cells (CCL), large cells, and combined CCL and large cells. Monoclonal or biclonal pattern (single or two bands) was observed in 42 samples, oligoclonal pattern (three or more bands) in 30, polyclonal (smear) in 11, and no products in 3. Large-cell-type lesions showed fewer bands than those with other histologic types, and 75% of cases with large-cell type had mono- or biclonal proliferation. Common clones were found among lesions in about 60% of cases. Especially in 4 cases including 2 cases with large-cell type, every lesion in the same case contained the common clones. These findings suggested that gastric MALT lymphoma started as multi- or oligoclonal proliferation of cells, in which separate lesions composed of different clones from each other. As disease advances, dominant clones appear in some lesion and disseminate to other lesions via homing properties of the proliferating B lymphocytes.

Aged↗
PubMed2001

Circadian rhythm and postural change in natriuresis in non-dipper type of essential hypertension.

Recently we found that, in non-dipper type of essential hypertensive patients who showed the lack of nocturnal fall in blood pressure, circadian rhythm of urinary sodium excretion rate was disturbed. In the present study we examined whether postural change in natriuresis is also disturbed in non-dippers. Sixteen inpatients with essential hypertension were maintained on a relatively high sodium diet containing 10 to 12 g of NaCl per day for 8 days. On the 7th day of the study period, 24-h ambulatory blood pressures were measured, and 5-7th days urinary samples were collected for both daytime and night-time. On the last day of the study period, patients stood for 2 h and then lay down for 2 h. Urinary volume and excretion rates of creatinine and sodium were measured every hour in both positions. Night-time urinary sodium excretion rate was significantly higher in non-dippers (n = 9) than that in dippers (n = 7). Night/day ratio of mean arterial pressure had a positive relationship with night/day ratio of urinary sodium excretion rate. In non-dippers, but not in dippers, the mean value of U(Na)V during upright position was significantly lower than that during supine position. There was a significantly negative relationship between upright/supine ratio of U(Na)V and night/day ratio of MAP or night/day ratio of U(Na)V. In patients with non-dipper type of essential hypertension, both natriuresis patterns, circadian rhythm and postural change, were disturbed.

Adult↗
PubMed2001

A leucine(7)-to-proline(7) polymorphism in the signal peptide of neuropeptide Y was not identified in the Japanese population.

OBJECTIVE: A Leu(7)-to-Pro(7) polymorphism exists in the signal peptide part of prepro-neuropeptide Y (NPY) and this polymorphism is associated with high serum cholesterol and LDL cholesterol levels in both Finnish and Dutch people. There was a significant difference in the allelic frequencies among populations with different genetic backgrounds. Therefore, the present study was designed to test whether Japanese people had the Leu(7)-to-Pro(7) polymorphism in the NPY signal peptide. METHODS: A total of 102 healthy Japanese volunteers supplied blood samples, from which leucocyte DNA was isolated. Primer pairs for the polymerase chain reaction (PCR) were made according to Karvonen et al. Direct sequencing of the PCR product was carried out by the dye terminator method using a capillary electrophoresis sequencer. RESULTS: All 102 young healthy Japanese subjects showed Leu(7)/Leu(7) but not Leu(7)/Pro(7) or Pro(7)/Pro(7) in the NPY signal peptide. CONCLUSION: The incidence of the Leu(7)-to-Pro(7) polymorphism in the signal peptide of NPY was extremely low in Japanese people, suggesting that the polymorphism producing Pro(7) is not one of the genetic determinant factors affecting serum cholesterol levels in Japanese people.

Adult↗
PubMed2001

A case of angiomyolipoma presenting as a huge retroperitoneal mass.

A 60-year-old man was admitted to Hitachi General Hospital, Hitachi, Japan, with general fatigue and epigastric fullness. A large mass was palpated on whole abdomen and abdominal computed tomography scan showed a large lobulated fatty mass surrounding the right kidney, which indicated the existence of angiomyolipoma arising from the right kidney. The tumor was success-fully resected through a thoracoabdominal incision. The total weight of the resected specimen was 3500 g, apparently the largest angiomyolipoma resected by operation in Japan.

Angiomyolipoma↗
PubMed2001

Location of the epitope for 7D5, a monoclonal antibody raised against human flavocytochrome b558, to the extracellular peptide portion of primate gp91phox.

Flavocytochrome b558 is the membrane component of the phagocyte NADPH oxidase, and is a heterodimer composed of gp91phox and p22phox subunits. Human flavocytochrome b558 is recognized by monoclonal antibody 7D5 at an unidentified extracellular domain, although our previous study suggested it might recognize p22phox. 7D5 has proven useful in rapid screening of individuals for X-linked chronic granulomatous disease by flow-cytometry. Therefore, we re-evaluated the location of the 7D5 epitope using gene-engineered cell lines expressing hybrid flavocytochromes composed of human and murine subunit homologues. The current study demonstrates that the 7D5 recognizes epitope only of primate gp91phox. Flow-cytometric analyses showed that 7D5 consistently bound to cells expressing human gp91phox. In addition, 7D5 immunoprecipitated the approximately 58 kDa unglycosylated gp91phox protein from solubilized membrane fractions of tunicamycin-treated PLB-985 granulocytes, indicating that glycans were not required for 7D5 binding. Transgenic COS7 cells expressing human gp91phox but not p22phox were recognized by 7D5. These results localized the epitope of 7D5 to an extracellular peptide portion of primate gp91phox and indicate that the antibody will be useful for monitoring the efficiency of gene therapy in patients with flavocytochrome b558-deficient chronic granulomatous disease and for elucidating structural characteristics of flavocytochrome b558.

3T3 Cells↗
PubMed2001

Umbilical vein thrombosis as a possible cause of perinatal morbidity or mortality: report of two cases.

Significant occlusion of the lumen of the umbilical vein by thrombus was observed in 2 patients with unexplained intrauterine fetal death (IUFD)/fetal distress. Although a normal non-stress testing result was obtained 7 days prior to IUFD in one patient, IUFD was noted during regular antenatal care at 39 weeks of gestation; intrapartum abrupt onset of deceleration in fetal heart rate pattern was observed at 40 weeks of gestation, lasting 14 min until vacuum extractor-assisted delivery in the other patient. Umbilical vein thrombosis was considered contributory to IUFD and the abrupt deterioration in fetal heart rate pattern in these 2 patients. Histological examination of the umbilical cord is thus important in unexplained fetal death/fetal distress.

Adult↗
PubMed2001

[The feasibility of a limited operation for primary lung cancer].

We reviewed 33 patients who underwent a limited operation for primary lung cancer between 1980 and 1998. These cases were divided into three groups; a poor risk group consisting of 18 patients who had a high risk such as pulmonary or cardiac dysfunction and who underwent partial resection of a lung, a reduction group consisting of 9 patients who had advanced lung cancer or uncontrolled cancer of an organ other than the lung and who underwent partial resection, and an active limited operation group consisting of 6 patients who underwent segmentectomy with lymphoadenectomy for the treatment of early lung cancer. The 1 and 3-year survival rates in the poor risk group, reduction group and active limited operation group were 73.9, 60.0, 100%, and 63.4, 0.0, 100%, respectively. The results of limited operations performed for poor risk cases were satisfactory in terms of both functional state and prognosis. Limited operations performed to reduce tumor in advanced lung cancer cases did not improve the prognosis. Although an active limited operation for a case of early lung cancer remains controversial with respect to indication, it is thought that this operation is not inferior to a standard radical operation (lobotomy with mediastinal lymphoadenectomy) in selective cases in which the maximum tumor diameter is 2 cm or less. The indication for a limited operation must be further examined from aspects of tumor size, tumor histology and the other factors of the tumor.

Adenocarcinoma↗
PubMed2001

[A case of transitional cell carcinoma of the urinary bladder with high serum level of CEA and CA19-9].

An 85-year-old male with asymptomatic gross hematuria was diagnosed with invasive bladder tumor, transitional cell carcinoma grade 3. Serum levels of CEA and CA19-9 were elevated and histological examination revealed expression of both markers in the cytoplasm of cancer cells. Out of therapeutic options, intra-arterial chemotherapy and radiotherapy were selected because of his age. During the treatment, serum levels of CEA and CA19-9 decreased along with reduction of tumor size. These serum markers have been reported to be elevated in 10 to 60% of patients with bladder tumor and are useful markers for evaluation of the treatment as suggested in the present case.

Aged↗
PubMed2001

Inverse correlation of thioredoxin expression with estrogen receptor- and p53-dependent tumor growth in breast cancer tissues.

Estrogen receptor (ER) and p53 are important transcription factors in the growth regulation of tumor cells in breast cancer. We reported previously that thioredoxin (TRX) regulates the DNA binding activities of ER and p53 in vitro. The expression of pS-2, a trefoil factor, is also correlated with that of ER. To clarify the regulation mechanism of tumor growth in breast cancer, here we investigated the expression of TRX, ER, pS-2, and p53 and the mitotic index (MI) in 147 breast cancer tissues using immunohistochemical analysis. Of 123 TRX+ cases, ER+ cases (n = 62) showed a higher pS-2 score and lower MI than did ER- cases (n = 61). Furthermore, p53- cases (no mutation in p53; n = 76) also showed a lower MI than did p53+ cases (n = 47). There was no significant correlation between pS-2 and ER, MI and ER, or p53 and MI in the TRX- group. Among the ER+ and p53- cases (ER+/p53- group; n = 61), MI was lower in the TRX+ group (n = 46) than in the TRX- group (n = 15). However, in all other groups (n = 86) with abnormalities in the immunohistochemical expression of either p53 or ER, there was no significant correlation between MI and TRX expression. In the TRX+ and ER +/p53- group (n = 46), histological grading was lower than that in all other groups (n = 101). These findings suggest that TRX expression is linked to the ER- and p53-dependent regulation of tumor growth in breast cancer. In addition, TRX expression in ER+ and p53 intact (wild-type p53+) groups may mean better prognosis than in other conditions.

Adult↗
PubMed2000

Possible association of thioredoxin and p53 in breast cancer.

Expression of thioredoxin (TRX), a dithiol-reducing enzyme, and mutations of p53 have been detected in various cancer tissues. We recently reported that TRX-dependent redox regulation plays a crucial role in DNA binding activity of p53. In this study, we investigated the possibility of functional association between TRX and p53 in breast cancer. First, we examined the expression of TRX and mutated p53 in 100 primary breast cancer tissues by immunohistochemistry. Expression of TRX was detected in cases of 84/100 (84%) and expression of p53, which means existence of mutated p53, in cases of 63/100 (63%). TRX positive cases was 89% (56/63) in mutant p53 positive cases. Next, we examined the expression of TRX and p53 in breast cancer cell line MCF-7 cells after CDDP treatment or irradiation. CDDP treatment or irradiation augmented expression of TRX and p53 in MCF-7 cells by western blotting. Immunofluorescence cell analysis by confocal microscopy showed that CDDP treatment induced translocation of TRX into nuclei. These results suggest the possible association of TRX with p53-dependent function including DNA repair in breast cancer.

Adult↗
PubMed2000

Selective potassium ion recognition by benzo-15-crown-5 fluoroionophore/gamma-cyclodextrin complex sensors in water.

Three fluoroionophores Cn (n = 1, 3, 5), in which the crown ether unit and pyrenyl moiety are connected by a -(CH2)n- spacer, have been used to construct supramolecular Cn/gamma-cyclodextrin (gamma-CyD) complexes for alkali metal ion sensing in water. The Cn (n = 3, 5) are found to selectively form 2:1 complexes with K+ in the presence of gamma-CyD and exhibit the pyrene dimer emission in water. Equilibrium analysis of the C3/gamma-CyD complex reveals that the observed dimer emission arises from a 2:1:1 complex of C3 with K+ and gamma-CyD. In the absence of K+, the fluorescence lifetimes for the dimer species ((C3)2CyD and (C3)2(CyD)2) and the monomer species (C3CyD and C3(CyD)2) are 13-18 and 130-180 ns, respectively. Upon addition of 0.10 M KCI, a rising component corresponding to pyrene excimer formation is observed at the dimer emission region. For the C3/gamma-CyD complex, the apparent association constant for K+ of (3.8 +/- 1.3) x 10(9) M(-2) is only slightly affected by the presence of Na+. Although the C5/gamma-CyD complex shows high sensitivity for K+, the selectivity for K+ over Na+ is lower than that of the C3/gamma-CyD complex. In contrast, fluoroionophore C1 with the shortest methylene spacer exhibits no response for alkali metal cations in the presence of gamma-CyD. These results demonstrate that the response function of supramolecular Cn/gamma-CyD complexes is strongly affected by the methylene spacer length of Cn. The highest K+ selectivity is obtained for the C3/gamma-CyD complexes in water.

Journal Article↗
PubMed2000

Abnormal expression of BRCA1 and BRCA1-interactive DNA-repair proteins in breast carcinomas.

Breast cancer is one of the most common malignancies among women. The molecular mechanisms involved in breast carcinogenesis, however, remain to be elucidated. Although somatic mutation of BRCA1 is rare, BRCA1 protein expression is reduced in about 30% of sporadic breast carcinomas (Yoshikawa et al., Clin. Cancer Res., 5:1249-1261, 1999), indicating its possible involvement even in sporadic breast carcinogenesis. Among the BRCA1-interactive proteins are hRAD51 (a human homologue of Escherichia coli rec A protein), BARD1 (BRCA1-associated RING domain 1) and p53, all of which are involved in DNA repair. We have analyzed the expression patterns of the hRAD51, BARD1 and p53 proteins in five breast cancer cell lines, including a BRCA1-deficient cell line, and in 179 breast cancer tissue samples from Japanese women, including 113 sporadic, 47 hereditary (i.e., BRCA1 status unknown), and 19 BRCA1-associated cases. Of the 179 breast carcinomas, fifty-four (30%) exhibited reduced hRAD51 expression, and sixty-two (35%) exhibited p53 overexpression. On the other hand, reduced expression level of BARD1, and of hMSH2 and hMLH1, which are components of DNA mismatch-repair pathway and are involved in colorectal carcinogenesis, was observed respectively in only 10 (6%), 8 (5%) and 3 (2%) cases. The overall frequency of sporadic breast carcinomas with abnormal expression of either BRCA1 or the BRCA1-interactive proteins was 67% (76/113). These results indicate that there may be an important role for the BRCA1-associated DNA-repair pathway, not only in BRCA1-associated breast carcinomas, but also in sporadic breast carcinomas.

Adaptor Proteins, Signal Transducing↗
PubMed2000

Fractalkine-mediated endothelial cell injury by NK cells.

Endothelial cells (ECs) are primary targets of immunological attack, and their injury can lead to vasculopathy and organ dysfunction in vascular leak syndrome and in rejection of allografts or xenografts. A newly identified CX3C-chemokine, fractalkine, expressed on activated ECs plays an important role in leukocyte adhesion and migration. In this study we examined the functional roles of fractalkine on NK cell activity and NK cell-mediated endothelial cell injury. Freshly separated NK cells expressed the fractalkine receptor (CX3CR1) determined by FACS analysis and efficiently adhered to immobilized full-length fractalkine, but not to the truncated forms of the chemokine domain or mucin domain, suggesting that fractalkine functions as an adhesion molecule on the interaction between NK cells and ECs. Soluble fractalkine enhanced NK cell cytolytic activity against K562 target cells in a dose- and time-dependent manner. This enhancement correlated well with increased granular exocytosis from NK cells, which was completely inhibited by the G protein inhibitor, pertussis toxin. Transfection of fractalkine cDNA into ECV304 cells or HUVECs resulted in increased adhesion of NK cells and susceptibility to NK cell-mediated cytolysis compared with control transfection. Moreover, both enhanced adhesion and susceptibility of fractalkine-transfected cells were markedly suppressed by soluble fractalkine or anti-CX3CR1 Ab. Our results suggest that fractalkine plays an important role not only in the binding of NK cells to endothelial cells, but also in NK cell-mediated endothelium damage, which may result in vascular injury.

Adjuvants, Immunologic↗