Biomedical subjects

K Sugihara

Publications and source records attributed to K Sugihara.

At least 55 records · Page 3Linked to original sources

PubMed2000

c-erbB-2 protein overexpression and p53 immunoreaction in primary and recurrent breast cancer tissues.

BACKGROUND AND OBJECTIVES: We investigated whether expression levels of c-erbB-2 and p53 proteins in breast cancer tissues differ in primary and metastatic lesions. METHODS: Immunohistochemical staining or sandwich enzyme immunoassay was used to determine expression levels of c-erbB-2 and p53 proteins in 42 breast cancer samples from 21 patients. Estrogen (ER) and progesterone receptors (PgR) were also measured by enzyme immunoassay in each case. All patients had undergone radical surgery for primary tumors and surgical resection of asynchronous metastatic lesions. Thirteen patients (62%) were premenopausal and 14 (67%) received postoperative adjuvant therapies. Median disease-free survival time was 26 months (range, 5-104). The resected metastatic lesions included 1 in the liver, 3 in the lung, and 3 in the supraclavicular lymph nodes. The remaining 14 were local skin lesions. RESULTS: There was no difference in the positivity rate of c-erbB-2 (38%: 8/21) and p53 (39%: 7/18) expression between the primary tumors and the recurrent lesions. In addition, no discordant c-erbB-2 or p53 expression was observed between the primary tumors and their respective metastatic lesions. Positivity rates for ER and PgR were 50% (10/20) and 60% (12/20) for the primary tumors, but only 25% (5/20) and 30% (6/20) for the recurrent lesions, respectively (P = 0. 19 for ER and P = 0.11 for PgR). CONCLUSIONS: c-erbB-2 and p53 expression levels in breast cancer cells were almost unchanged as the disease progressed and/or in response to adjuvant therapies, regardless of the hormone receptor status.

Adult↗

PubMed2000

Microvasculature of small liver metastases in rats.

Neovascularization is important in the development of liver metastasis. We sought to define the origin and fine structure of the blood supply of small experimental liver metastases in rats using an injection replica method. Liver metastases were produced by intraportal inoculation of ascitic fluid containing AH60C hepatoma cells in male Donryu rats (n = 40). Intrahepatic microvasculature was studied by scanning electron microscopy and by stereomicroscopy of microvascular casts produced by perfusion via the abdominal aorta or portal vein 7 days following tumor inoculation. Intrahepatic microvasculature in rats without liver metastases (n = 10) also was studied by scanning electron microscopy. In the normal liver, branches of the hepatic artery typically terminated in the peribiliary plexus and less frequently led to sinusoids and terminal portal veins. In 69 metastatic tumors ranging from 269 to 1875 microm in diameter, arterially perfused metastatic tumors larger than 300 microm showed newly developed neovascularization. Portally perfusion of metastatic tumors did not visualize neovascularization irrespective of tumor size. At the periphery of metastases, tumor vessels disclosed by arterial perfusion most often communicated with the peribiliary plexus and less frequently with terminal arterioles. Metastatic liver tumors as small as 300 microm in diameter receive their main blood supply from the hepatic artery but not from the portal vein, and tumor vessels more often are derived from the arterially filled peribiliary plexus rather than from terminal arterioles.

Animals↗

PubMed2000

Endorectal ultrasonography and treatment of early stage rectal cancer.

The purpose of this study was to evaluate the accuracy of preoperative staging by endorectal ultrasonography (EUS) and its contribution to treatment of early stage rectal cancer (ESRC). The results of EUS for 154 consecutive patients with ESRC (pTis to pT2) were compared prospectively with histologic findings, assessed according to the TNM classification. Results of treatment selection and long-term outcomes were analyzed retrospectively. There were 35 patients histologically staged as pTis, 8 as pT1-slight (invasion confined to the superficial one-third of the submucosa), 37 as pT1-massive (invasion extending to the deeper submucosa), and 74 as pT2. The equipment used was an echoendoscope GF-UM2 or GF-UM3 (Olympus, Tokyo, Japan). Sensitivity/specificity/overall accuracy rates for detection of slight submucosal invasion, massive submucosal invasion, and muscularis propria invasion were 99%/74%/96%, 98%/88%/97%, and 97%/93%/96%, respectively. Incidences of lymph node metastasis in pTis, pTis to pT1-slight, pT1, pT1-massive, and pT2 cases were 0%, 0%, 18%, 22%, and 30%, respectively. Incidences of lymph node metastasis in ESRCs staged by EUS (u) as uTis, uT1-slight, uT1-massive, uT2, and uT3 by EUS were 0%, 0%, 26%, 36%, and 64%, respectively. Sensitivity, specificity, and overall accuracy rates for detection of positive nodes in overall ESRCs were 53%, 77%, and 72%, respectively. Of the 43 patients with pTis to pT1-slight tumors, 22 underwent endoscopic polypectomy or local excision, 20 radical surgery, and 1 radical surgery after endoscopic polypectomy due to vascular invasion. All these patients are alive and all but one (who refused radical surgery due to vascular invasion after local excision and developed liver and lung metastases) are disease-free. Of the 37 patients with pT1-massive tumors, 34 underwent radical surgery and 3 transcoccygeal segmental resection. All these patients are alive disease-free except for one who died of peritoneal carcinomatosis after radical surgery. All patients with pT2 tumors underwent radical surgery. The overall 5-year survival rates for pTis, pT1, and pT2 cases were 100%, 98%, and 97%, respectively. EUS is an accurate method for evaluating invasion depth in ESRC. Patients with uTis or uT1-slight tumors staged by EUS are at low risk of positive nodes and good candidates for endoscopic polypectomy or local excision. Those with uT1-massive or uT2 lesions should be treated with a radical operation because of the high incidence of positive nodes.

Adenocarcinoma↗

PubMed2000

Assessment of intestinal viability using a non-contact laser tissue blood flowmeter.

BACKGROUND: Intraoperative assessment of small intestinal viability following ischemic insult from arterial occlusion has remained difficult. The purpose of the present study was to assess the applicability of non-contact tissue blood flowmeter (NCLBF) with regard to intraoperative assessment of intestinal viability. METHODS: Using the ischemia-reperfusion model of rabbits, the relationship between the records of NCLBF, pulse oximetry (PO), and histological grade and the comparison of accuracy of intestinal viability among NCLBF, PO, and fluorescein (FL) were examined. RESULTS: There was a significant relationship between NCLBF and the histological grade (coefficient-0.80, P <0.0001); however, PO was not related. The accuracy and sensitivity of bowel viability of NCLBF (76%, 88%) were better than those of PO (58%, 23%) and FL (48%, 4%), respectively (P <0.001). CONCLUSIONS: NCLBF is useful to assess intestinal viability, suggesting the possibility of clinical use.

Animals↗

PubMed2000

Foreign gene expression by in vivo gene electroporation in the quail testis.

To investigate whether or not foreign gene expression is attained in the testis of living Japanese quails, a firefly luciferase reporter gene was transfected by in vivo electroporation (EP), and transcriptional activity of different promoters was compared. In addition, the effect of the Epstein-Barr virus self-replication sequence was also tested. The results showed that luciferase activity in the testis reached almost a plateau value at 50 V. Under this EP condition, no difference was found in transcriptional activity between the simian virus 40 (SV40) and miw promoters. The reporter gene expression in the quail testis was observed over 28 days after in vivo gene EP, although the activity gradually decreased, and the presence of the Epstein-Barr virus self-replication sequence in the SV40 promoter did not significantly prolong the luciferase activity. These results suggest that in vivo gene EP confers strong, though transient, foreign gene expression in the Japanese quail, and it may provide a new powerful approach for studies on transcriptional regulation of genes during proliferation and differentiation of spermatogenic cells in the quail testis.

Animals↗

PubMed2000

Cynomolgus monkey liver aldehyde oxidase: extremely high oxidase activity and an attempt at purification.

Aldehyde oxidase (EC 1.2.3.1) in monkey (Macaca fascicularis) liver was characterized. Liver cytosol exhibited extremely high benzaldehyde and phthalazine oxidase activities based on aldehyde oxidase, compared with those of rabbits, rats, mice and guinea pigs. Monkey liver aldehyde oxidase showed broad substrate specificity distinct from that of the enzyme from other mammals. Purified aldehyde oxidase from monkey liver cytosol showed two major bands and two minor bands in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). These bands were also observed in Western blotting analysis using anti-rat aldehyde oxidase. The molecular mass of the enzyme was estimated to be 130-151 kDa by SDS-PAGE, and to be about 285 kDa by HPLC gel filtration. The results suggest that isoforms of aldehyde oxidase exist in monkey livers.

Aldehyde Oxidase↗

PubMed2000

Higher osteoclastic demineralization and highly mineralized cement lines with osteocalcin deposition in a mandibular cortical bone of autosomal dominant osteopetrosis type II: ultrastructural and undecalcified histological investigations.

In this study we report on histological and ultrastructural investigations of the mandibular cortical bone in a case of autosomal dominant osteopetrosis type II complicated by mandibular osteomyelitis. Histologically, there was a marked increase in the number and size of osteoclasts on the inner bone surface. An undecalcified preparation showed a pair of deeply stained (highly demineralized) and stain-phobic (highly mineralized) layers on the bone surface just beneath the osteoclasts. The layers were incorporated into the bone matrix during the remodeling process as thickened cement lines. A contact microradiogram of the cortical bone revealed highly mineralized layers at the cement lines, which were closely correlated with immunohistochemical evidence of deposition of osteocalcin at the thickened cement lines. Ultrastructural examination showed that the osteoclasts had a typical clear zone, but they were deficient in ruffled border formation and had numerous lysosomal vacuoles containing dense substances. An electron-dense amorphous material layer was present on the bone surface just beneath the osteoclasts as well as at the cement lines. The layer was partly composed of a short fibrillar material, and it partially revealed the lamellar structure. Consequently, an osteoclastic malfunction might be primarily involved in the process of bone matrix resorption rather than demineralization, resulting in higher demineralization and abnormal material deposition on the bone surface and at the cement lines. Furthermore, evidence of active osteoclastic bone resorption with a brush border formation at the bone involved in the inflammatory lesion in this case suggests that the osteoclastic malfunction is influenced and recovered by a microenvironment such as inflammatory cytokines.

Bone Density↗

PubMed2000

Calcium/calmodulin inhibits the binding of specific [125I]omega-conotoxin GVIA to chick brain membranes.

The effect of Ca2+/calmodulin (CaM) on the specific binding of [125I]omega-conotoxin GVIA (125I-omega-CTX) to crude membranes from chick brain was investigated. When we examined the effects of the activation of various endogenous protein kinases on specific [125I]omega-CTX binding to crude membranes, we observed that Ca2+/CaM had an inhibitory effect regardless of whether or not the standard medium contained ATP (0.5 mM). Ca2+/CaM also had an inhibitory effect in a simple binding-assay medium containing HEPES-HCl buffer, BSA, Ca2+ and CaM, and this effect was dependent on the concentration of Ca2+. The effect of Ca2+/CaM was attenuated by the CaM antagonists W-7 and CaM-kinase II fragment (290-309). An experiment with modified ELISA using purified anti omega-CTX antibody indicated that Ca2+/CaM did not affect the direct binding of [125I]omega-CTX and CaM. These results suggest that Ca2+/CaM either directly or indirectly affects specific [125I]omega-CTX binding sites, probably N-type Ca2+ channels in crude membranes from chick whole brain.

Animals↗

PubMed2000

Characteristics of the inhibitory effect of calmodulin on specific [125i]omega-conotoxin GVIA binding to crude membranes from chick brain.

The characteristics of the inhibitory effect of calcium ion (Ca2+)/calmodulin (CaM) on specific [125I]-omega-conotoxin GVIA (125I-omega-CTX) binding and on the labeling of 125I-omega-CTX to crude membranes from chick brain were investigated. The inhibitory effect of Ca2+/CaM depended on the concentrations of free Ca2+ and CaM. The IC50 values for free Ca2+ and CaM were about 2.0 x 10(-8) M and 3.0 microg protein/ml, respectively. The inhibitory effect of Ca2+/CaM was attenuated by the CaM antagonists W-7, prenylamine and CaM-kinase II fragment (290-309), but not by the calcineurin inhibitor FK506. Ca2+/CaM also inhibited the labeling of a 135-kDa band (which was considered to be part of N-type Ca2+ channel alpha1 subunits) with 125I-omega-CTX using a cross-linker. These results suggest that Ca2+/CaM affects specific 125I-omega-CTX binding sites, probably N-type Ca2+ channel alpha1 subunits, in crude membranes from chick whole brain.

Animals↗

PubMed2000

Clinical evaluation of lymphoscintigraphy with a new technetium compound for metastatic cervical lymphadenopathy.

OBJECTIVES: To evaluate the potential usefulness of lymphoscintigraphy for the detection of metastatic cervical lymphadenopathy. METHODS: Dynamic and static lymphoscintigraphy with 99Tcm-HSA-D was performed in 23 patients with malignant oropharyngeal tumors. The internal jugular nodes were excised and examined pathologically. The results of the lymphoscintigraphy were compared with the pathological examination and clinical palpation for accuracy. RESULTS: All cases showed abnormal findings on lymphoscintigraphy. The accuracy on dynamic scintigraphy was 69% for asymmetric drainage, 69% for delayed drainage and 100% for inverse drainage. The overall accuracy for each side was 71%. With static scintigraphy, the accuracy was 69% for asymmetry, 86% for fitting defect, 67% for mottled-patchy appearance, 70% in swelling and 100% for collateral pathway. The overall accuracy for each side was 74%. The agreement between lymphoscintigraphy and palpation was 44%. CONCLUSIONS: Lymphoscintigraphy with 99Tcm-HSA-D was superior to palpation. The method is useful as a supplementary modality for the evaluation of metastatic cervical lymphadenopathy because of its relatively high accuracy and a low false-negative rate.

Adult↗

PubMed2000

Small diameter vascular prosthesis with a nonthrombogenic phospholipid polymer surface: preliminary study of a new concept for functioning in the absence of pseudo- or neointima formation.

The purpose of this study was to prepare a small diameter vascular prosthesis functioning without pseudointima formation. A nonthrombogenic phospholipid polymer, the 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer, has a cell membrane-like structure and has demonstrated strong nonthrombogenicity. We have recently prepared 2 kinds of vascular prostheses, 2 mm in diameter, composed of the MPC polymer and segmented polyurethane (SPU). One includes 7.5 wt% MPC polymer (SPU/MPC[7.5] prosthesis), and the other includes 10.0 wt% (SPU/MPC[10] prosthesis). These prostheses were placed in rabbit carotid arteries and were retrieved at 1 and 4 weeks after implantation. A pseudointima was observed at 4 weeks on the SPU/MPC(7.5). For the SPU/MPC(10), the surface was macroscopically clear without a pseudointima even after a 4 week implantation. It appears that the SPU/MPC(10) prosthesis, functioning without a pseudointima, possesses a stronger nonthrombogenicity and would be more applicable for clinical use.

Anastomosis, Surgical↗

PubMed2000

Lymphoscintigraphy for interpretation of changes of cervical lymph node function in patients with oral malignant tumors: comparison of Tc-99m-Re and Tc-99m-HSA-D.

OBJECTIVE: The purpose of this study is to compare the usefulness of technetium-99m-rhenium colloid (Tc-99m-Re) and technetium-99m-human serum albumin diethylene-triamine-pentaacetic acid (Tc-99m-HSA-D) as lymphoscintigraphic agents and to discuss the significance of lymphoscintigraphy in comparison with computed tomography (CT), magnetic resonance imaging (MRI), and ultrasonography (US). STUDY DESIGN: Dynamic and static lymphoscintigraphies were performed with Tc-99m-Re and Tc-99m-HSA-D. The usefulness of the 2 agents was evaluated statistically in comparison with pathologic findings and palpation. The significance of lymphoscintigraphy is discussed in comparison with CT, MRI, and US (by the literature of CT, MRI, and US). RESULTS: Lymphoscintigraphy was superior to palpation, and Tc-99m-Re was superior to Tc-99m-HSA-D in accuracy, specificity, and the incidence of true-positive and false-positive. Statistical significance was shown between the static lymphoscintigraphy with Tc-99m-Re and palpation. The reliability of lymphoscintigraphy seemed to be slightly inferior to CT and MRI in specificity and accuracy. However, lymphoscintigraphy had some advantages that CT and MRI lacked; for example, it showed very high sensitivity (100%) and no false-negative (0%). It also showed changes of lymph node function, showed all levels of neck nodes at one time, and showed a possibility of detecting small lymph node metastases. CONCLUSION: Lymphoscintigraphy was more useful than palpation in detecting lymph node metastases, and Tc-99m-Re was superior to Tc-99m-HSA-D as an agent. Lymphoscintigraphy is significant when it is performed as a preliminary examination before CT or MRI.

Adult↗

PubMed2000

Reduction of hydroxamic acids to the corresponding amides catalyzed by rabbit blood.

1. The hydroxamic acids N-hydroxyphenacetin and N-hydroxy-2-acetylaminofluorene were reduced to the corresponding amides, phenacetin and 2-acetylaminofluorene respectively by rabbit blood supplemented with both NAD(P)H and FAD. These reducing activities were found in erythrocytes but not in plasma, and were sensitive to inhibition by carbon monoxide and oxygen. When blood or erythrocytes were boiled, these activities were not abolished. 2. Haemoproteins such as haemoglobin and catalase exhibited the reductase activity in the presence of both NAD(P)H and FAD under anaerobic conditions. The activity was not abolished when the haemoproteins were boiled. 3. Haematin showed a significant reducing activity in the presence of these cofactors. The activity of haematin was also observed with the photochemically reduced form of FAD. 4. The reduction system in blood was composed of NAD(P)H, FAD and haemoglobin. Reduction appears to proceed in two steps, i.e. the reduction of FAD by NADH or NADPH, followed by the non-enzymatic reduction of the hydroxamic acids to the amides by reduced FAD, catalyzed by the haem group of haemoglobin in rabbit erythrocytes.

2-Acetylaminofluorene↗

PubMed2000

Molecular characterization of cDNA encoding oxygen evolving enhancer protein 1 increased by salt treatment in the mangrove Bruguiera gymnorrhiza.

Young plants of the common Okinawa mangrove species Bruguiera gymnorrhiza were transferred from freshwater to a medium with seawater salt level (500 mM NaCl). Two-dimensional gel electrophoresis revealed in the leaf extract of the plant a 33 kDa protein with pI 5.2, whose quantity increased as a result of NaCl treatment. The N-terminal amino acids sequence of this protein had a significant homology with mature region of oxygen evolving enhancer protein 1 (OEE1) precursor. The cloning of OEE1 precursor cDNA fragment was carried out by means of reverse transcription-PCR (RT-PCR) using degenerated primers. Both 3'- and 5'-regions were isolated by rapid amplification of cDNA ends (RACE) method. The deduced amino acid sequence consisted of 322 amino acids and was 87% identical to that of Nicotiana tabacum. In B. gymnorrhiza, the predicted amino acid sequence of the mature protein starts at the residue number 85 of the open reading frame. The first 84-amino acid residues correspond to a typical transit sequence for the signal directing OEE1 to its appropriate compartment of chloroplast. The expression of OEE1 was analyzed together with other OEE subunits and D1 protein of photosystem II. The transcript levels of all the three OEEs were enhanced by NaCl treatment, but the significant increase of D1 protein was not observed.

Algal Proteins↗

PubMed2000

In vivo gene electroporation confers strong transient expression of foreign genes in the chicken testis.

To attain foreign gene expression in vivo in the testis of living chickens, chloramphenicol acetyltransferase (CAT) and firefly luciferase reporter genes were transfected by electroporation (EP). Bioluminescence imaging indicated clear expression of the luciferase reporter gene localized in and around the injection site of the chicken testis. The CAT activity decreased sharply from 7 to 14 d posttransfection (P < 0.01) and remained low until 28 d. The presence of the self-replication sequence of Epstein-Barr virus did not give significantly higher CAT gene expression over the 28-d posttransfection. The results suggest that in vivo gene EP confers strong, likely transient, foreign gene expression in the testis of living chickens.

Animals↗

PubMed2000

Significant increase in prostaglandin E-main urinary metabolite by laxative administration: comparison with ulcerative colitis.

OBJECTIVE: To assess the production of prostaglandin E(2), an important chemical mediator in diarrhea induced by laxative administration, a prostaglandin E-main urinary metabolite (7alpha-hydroxy-5,11-diketotetranor-prosta-1,16-dioic acid, PGE-MUM) was measured in healthy volunteers and compared with the values of patients with ulcerative colitis. METHODS: PGE-MUM was determined by a simplified immunoassay of bicyclic PGE-MUM and analyzed for the influence of laxative administration and active/remission phases of ulcerative colitis. RESULTS: Administration of laxatives induced a significant increase in PGE-MUM in healthy volunteers. A significant elevation was also found in the active as compared with the remission phase of ulcerative colitis. The PGE-MUM levels were significantly correlated with our modified Talstad scores, clinical disease activity indices in ulcerative colitis. It was confirmed by time course studies of individual patients that changes in PGE-MUM correlated well with colitis activity. CONCLUSION: Laxative administration induces production of prostaglandin E(2) as one of the chemical mediators, although its production grade is relatively low as compared with ulcerative colitis in the active phase.

Aged↗

PubMed2000

Trophinin expression in the mouse uterus coincides with implantation and is hormonally regulated but not induced by implanting blastocysts.

Trophinin mediates apical cell adhesion between two human cell lines, trophoblastic teratocarcinoma and endometrial adenocarcinoma. In humans, trophinin is specifically expressed in cells involved in implantation and early placentation. The present study was undertaken to establish trophinin expression by the mouse uterus. In the pregnant mouse uterus, trophinin transcripts are expressed during the time which coincides with the timing of blastocyst implantation. Trophinin is also expressed in the nonpregnant mouse uterus at estrus stage. Uteri from ovariectomized mice did not express trophinin, whereas strong expression was induced by estrogen but not by progesterone. Trophinin transcripts and protein were found in the pseudopregnant mouse uterus. No differences were detected in trophinin expression by the uteri in the pregnant, pseudopregnant, and pseudopregnant received blastocysts. In delayed implantation model, trophinin proteins were found in both luminal and glandular epithelium, whereas dormant blastocysts were negative for trophinin. Upon activation with estrogen, however, no significant changes were detected either in the blastocyst or in the uterus. These results indicate that ovarian hormones regulate trophinin expression by the mouse uterus, and that an implanting blastocyst has no effect on trophinin expression in the surrounding endometrial luminal epithelial cells.

Animals↗

PubMed2000

Ultrasound-guided core needle biopsy for breast cancer: preliminary report.

BACKGROUND: Ultrasound-guided automated percutaneous core needle biopsy (US-CNB) for breast tumors has been introduced into clinical practice, but it has not yet been used routinely. We evaluated its usefulness, especially in terms of histological accuracy. METHODS: Thirty-one consecutive patients underwent mammography followed by breast biopsy with the automated core needle biopsy device. RESULTS: Mammography was highly suggestive of malignancy or suspicious abnormalities in 17 cases whose histological findings from US-CNB specimens were invasive ductal carcinoma without exception. The other 14 cases with benign or probably benign mammography findings showed no malignancy histologically in the US-CNB specimens. In cases of malignancy, the accuracy rates of histological findings for the specimens obtained by US-CNB were 94.1% in histological type, 100% in direct infiltration, 82.4% in lymphatic infiltration, 82.4% in venous infiltration, 94.1% in histological grading and 82.4% in intraductal spread. CONCLUSION: US-CNB was useful for making reliable preoperative histopathological diagnosis and may substitute fine needle aspiration biopsy and surgical biopsy.

Biopsy↗