Biomedical subjects

T Ueki

Publications and source records attributed to T Ueki.

At least 73 records · Page 4Linked to original sources

PubMed1998

Secretory carcinoma of the breast in an elderly woman: report of a case.

We herein report a case of secretory carcinoma of the breast in a 73-year-old woman. Secretory carcinoma is an extremely rare tumor and demonstrates distinctive pathologic characteristics. This tumor frequently occurs in either children or adolescents, and thus has been called juvenile carcinoma. We encountered this rare tumor in an elderly woman. Aspiration biopsy cytology was performed twice, but the cytological diagnosis was not carcinoma. Such pathologic characteristics as mild atypia, the absence of hyperchromasia, and a minimal degree of pleomorphism in the tumor cells can thus lead to a cytological misdiagnosis. An excisional biopsy was performed and secretory carcinoma was finally diagnosed. Consequently, a modified radical mastectomy (Kodama's method) was performed 7 days later. We describe this very rare tumor's clinicopathologic characteristics.

Age Factors↗

PubMed1998

HVJ-liposome mediated gene transfer into hepatocytes in vivo.

BACKGROUND/AIMS: The efficient transduction of appropriate target cells will be critical for gene therapy. We evaluated the suitability of hemagglutinating virus of Japan (HVJ)-liposome-mediated gene transfer for gene therapy of liver diseases. METHODS: The Escherichia coli beta-galactosidase (beta-gal) gene was introduced into rat liver by HVJ-liposome to examine gene transfer efficacy and persistence of expression with or without partial hepatectomy prior to transfection. RESULTS: About 30% of hepatocytes were transduced after portal vein injection. Gene expression was transient, with only 2% of hepatocytes expressing beta-gal after 4 weeks. However, partial hepatectomy performed 24 h prior to injection resulted in persistently high levels of beta-gal for 4 weeks after injection. A 247-bp beta-gal polymerase chain reaction fragment transcript was detected in livers of transfected rats, but not in livers of control rats. The rat livers following gene transfer were histologically normal, and serum glutamic-pyruvic transaminase was not found to be elevated in rats. CONCLUSIONS: Our results demonstrate that HVJ-liposome-mediated gene transfer produced high gene transduction and persistent gene expression in the liver.

Alanine Transaminase↗

PubMed1998

Astrocytic gap junction blockage and neuronal Ca2+ oscillation in neuron-astrocyte cocultures in vitro.

We have investigated the effects of gap junction inhibitors, octanol, halothane, sodium propionate and lindane, on neuronal periodic Ca2+ transients in neuron-astrocyte coculture systems. Octanol reduced the amplitude and frequency of Ca2+ oscillations in dose-dependent manner. One mM octanol caused a complete disappearance of Ca2+ oscillations. Similar suppressions were obtained by halothane (1 mM) and sodium propionate (25 mM). In contrast, lindane (300 nM) uniquely raised the basal level of [Ca2+], in oscillating neurons as well as the height of apparent amplitude without changes in the frequency. The current results imply that octanol, halothane and sodium propionate might lower the frequency of spontaneous Ca2+ oscillations by blocking the gap junctional communication of neighboring astrocytes and that lindane, though also blocking the gap junctions, might not affect the frequency but reversely increase both the basal [Ca2+]i and the amplitude, probably due to an increase of neuronal [Ins (1.4.5)P3]i. These findings strongly suggest that astrocytes contribute to the generation of periodic neuronal Ca2+ oscillations through astrocytic gap junctional communications and/or other signaling components between astrocytes and neurons.

Animals↗

PubMed1998

Persistent gene expression in rat liver in vivo by repetitive transfections using HVJ-liposome.

Most viral vectors are highly immunogenic and are of limited use for somatic gene therapy that requires repetitive administrations. We have developed a highly efficient gene transduction procedure useful for repetitive transfections using liposome containing hemagglutinating virus of Japan (HVJ-liposome). The Escherichia coli beta-galactosidase (beta-gal) gene was embodied in HVJ-liposome, and introduced directly into the caudal lobe of rat liver that was transiently isolated from a systemic circulation. A 116 kDa beta-gal protein was detected in transfected rat liver tissues by Western blot analysis and it was expressed in more than two-thirds of the liver by histological staining. It was found that the transfection efficiency was not affected by repetitive transfections. In support of these findings, antibody response to HVJ-liposome detected in the rat sera was weak and transient. Furthermore, cytotoxic T lymphocytes were not elicited against autologous rat hepatocytes that were transfected in vivo using HVJ-liposome. Thus, our results demonstrate that the isolation of a target liver from systemic circulation and the direct administration of foreign genes using HVJ-liposomes are useful for high gene transduction and persistent gene expression in the liver.

Animals↗

PubMed1998

A new sigma factor, SigD, essential for stationary phase is also required for multicellular differentiation in Myxococcus xanthus.

BACKGROUND: Myxococcus xanthus is a gram-negative bacterium that undergoes spectacular development to form multicellular fruiting bodies under nutrient deprivation. Inside a fruiting body, vegetative cells differentiate into spores. A number of sigma factors have been shown to play roles in the regulation of gene expression in the M. xanthus life cycle. Additional sigma factors were searched to further explore the M. xanthus life cycle. RESULTS: A new sigma factor was identified, SigD, which consists of 297 amino acid residues. Two transcription initiation sites for the sigD gene were detected by primer extension analysis using total RNA from the vegetative and developmental cells, one of which was specific for development. The characterization of sigD-lacZ fusion strains demonstrated that sigD expression increased during entry into stationary phase of vegetative growth and during early development. A deletion mutant of sigD exhibited growth defects during the late-log phase and stationary phase, with dramatically reduced cell viability. The patterns of protein synthesis at late log phase of vegetative growth and at early development on CF agar plates were significantly different between the deletion mutant and the wild-type strain. The deletion mutant was more sensitive to various stresses when compared with the wild-type strain and did not accumulate trehalose in response to osmotic stress. The deletion mutant also showed a significant delay in fruiting body formation and sporulation and yielded fewer spores than the wild-type strain. CONCLUSIONS: SigD shows characteristic features of the stationary phase sigma factors and also plays important roles in multicellular differentiation of M. xanthus.

Amino Acid Sequence↗

PubMed1998

The alpha1L-adrenoceptor subtype in the lower urinary tract: a comparison of human urethra and prostate.

OBJECTIVE: To identify the alpha1-adrenoceptor subtypes present in the human urethra, by comparing the affinity of prazosin for alpha1-adrenoceptors in the rabbit, dog and human prostatic urethra, and in the dog and human prostate. MATERIALS AND METHODS: The study comprised samples of human prostate and prostatic urethra, obtained by open prostatectomy of patients with benign prostatic hyperplasia, and of the proximal urethra and prostate from male Beagle dogs and rabbits. Specimens were homogenized, filtered and pelleted by centrifugation. Nonspecific binding was determined in the presence of 1 mmol/L prazosin when assessing [3H]YM-617 (tamsulosin) binding, and 10 mmol/L phentolamine when assessing [3H]prazosin binding. Specific binding was defined as the difference between total binding and nonspecific binding. RESULTS: The dissociation constant for [3H]prazosin in the human prostate (0.088 nmol/L) was less than that in the rabbit urethra (0.299 nmol/L), dog urethra (0.604 nmol/L), dog prostate (0.482 nmol/L) and human urethra (0.254 nmol/L). The affinity of prazosin was also investigated by determining the potency of the inhibition of [3H]YM-617 binding. The affinity of prazosin for alpha1-adrenoceptors in the human urethra (Ki, 2.5 nmol/L) was lower than its affinity for alpha1-adrenoceptors in the human prostate (Ki, 0.25 nmol/L) and all of the cloned subtypes (Ki, 0.26-0.44 nmol/L). CONCLUSION: The alpha1L-adrenoceptor subtype is more prominent in the human, rabbit and dog urethra and dog prostate than in the human prostate.

Adrenergic alpha-Antagonists↗

PubMed1998

Guanidine hydrochloride-induced changes of the E2 inner core of the Bacillus stearothermophilus pyruvate dehydrogenase complex.

The limited proteolysis of the Bacillus stearothermophilus pyruvate dehydrogenase complex by V8 protease yields its core structure solely composed of lipoate acetyltransferase (E2) fragments. The changes in the core with guanidine hydrochloride (GdnHCl) were biphasic: below 0.8 M (first) and above 1.0 M (second) GdnHCl. The changes in the first phase were slight but significant: decreases in ellipticity and light scattering, and an increase in E2 activity. Insignificant changes in the molecular shape and size of the core were detected on fluorescence spectroscopy, ultracentrifugation, gel filtration, and electron microscopy. On the other hand, the changes in the second phase were drastic; the core was disassembled and denatured.

Chromatography, Gel↗

PubMed1998

Retrovirus-mediated gene therapy for human hepatocellular carcinoma transplanted in athymic mice.

Gene therapy using a retrovirus vector carrying herpes simplex virus thymidine kinase gene under the control of the 0.3-kb human alpha-fetoprotein (AFP) gene promoter (LNAF0.3TK virus) in combination with ganciclovir (GCV) treatment was performed in athymic mice harboring AFP-producing HuH-7 human hepatoma cells. GCV treatment resulted in pronounced growth inhibition of the virus-infected HuH-7 xenograft in mice, but did not affect growth of the parental xenograft. These results indicate that the AFP gene promoter sequence allows enough therapeutic gene expression to induce the GCV-mediated cytotoxicity in vivo in AFP-producing human hepatoma cells.

Animals↗

PubMed1998

Expressions of basic fibroblast growth factor and fibroblast growth factor receptor mRNA in soft tissue tumors by in situ hybridization.

Basic fibroblast growth factor (bFGF) is a mitogenic and angiogenic polypeptide produced by diverse cell types, including the cells derived from normal tissue and neoplastic lesions. To evaluate the possible differential expression of bFGF in soft tissue tumors, we examined 17 frozen primary soft tissue tumors including extra-abdominal desmoids, leiomyosarcomas, synovial sarcomas, myxoid liposarcomas, and alveolar soft part sarcomas by nucleic acid in situ hybridization. Three of the four leiomyosarcomas and two of the three synovial sarcomas studied expressed bFGF mRNA, whereas all of the myxoid liposarcomas and alveolar soft part sarcomas were negative. Two of the leiomyosarcomas were also positive for FGF receptor mRNA. These results indicated the possibility of an autocrine or paracrine mechanism in the function of bFGF and also lent support to the opinion that in situ hybridization is useful for examining cell character.

Adolescent↗

PubMed1997

Establishment and characterization of a new synovial sarcoma cell line, SN-SY-1: special reference to bcl-2 protein and SYT-SSX1 hybrid transcripts.

We established and characterized a new human synovial sarcoma cell line, SN-SY-1, derived from a monophasic fibrous synovial sarcoma excised from the abdominal wall of a 21-year-old man. We maintained the cell line for over 35 passages in vitro. The SN-SY-1 cells in vitro exhibit spindle and polygonal shapes and join to form an epithelial plaque. SN-SY-1 maintained a consistent karyotype: 46,t(X;18)(p11.2;q11.2), Y, t(6;8) (q13-15;q11-13), the same as that of the primary tumor specimen. RT-PCR assay for chimeric SYT-SSX transcripts followed by digestion with restriction enzymes revealed SYT-SSX1 fusion protein. An immunohistochemical study revealed expression of bcl-2 protein in the SN-SY-1 cell line, in vitro and in vivo. However, DNA analysis showed no rearrangement of the bcl-2 gene, and expression of bcl-2 mRNA was low. Why bcl-2 protein was expressed in this synovial sarcoma was not clarified.

Abdominal Neoplasms↗

PubMed1997

Peripheral development of cranial nerves in a cyclostome, Lampetra japonica: morphological distribution of nerve branches and the vertebrate body plan.

The development of peripheral nerves was studied in a Japanese marine lamprey, Lampetra japonica, in whole-mount and sectioned embryos from hatching until the earliest ammocoete. Nerve fibers were immunohistochemically stained with a monoclonal antibody against acetylated tubulin. Branchiomeric nerves first developed in a simple metamerical pattern, each associated with a single pharyngeal arch. Of those, the ophthalmicus profundus, maxillomandibular, and facial nerves later developed a highly modified branching pattern, whereas postotic nerves were less specialized and showed the stereotypical branching pattern of post-trematic nerves. The early distribution of melanocytes in myotome-free space largely overlapped with the morphology of the cranial nerve and ganglion anlage, and resembled the cephalic crest cell distribution pattern in the early chick embryo. It was suggested that the cephalic crest cell distribution, which is also inhibited by myotomes in the lamprey, would be the common basis for branchiomeric nerve patterning. In later development of the lamprey embryo, myotomes 1 through 3, which had originated in the postotic region, grew rostrally into the preotic region, laterally covering all of the branchiomeric nerves. This results in a deep position of the cranial nerves, which is not observed in gnathostomes.

Animals↗

PubMed1997

Murine interleukin 4 transgenic heart allograft survival prolonged with down-regulation of the Th1 cytokine mRNA in grafts.

BACKGROUND: Data supporting the differential activation of T helper (Th) 2 cells in transplantation acceptance/tolerance in rodents have been presented by several investigators. However, the differential activation of Th2 cells may be simply the result of allograft acceptance/tolerance induction instead of a contribution to the maintenance of grafts. METHODS: Therefore, we established interleukin (IL)-4 transgenic mice under the control of a cardiac alpha-myosin heavy chain promotor and transplanted IL-4-expressing heart allografts into unmodified recipients to determine the actual contribution of the Th2 bias to allograft acceptance. RESULTS: Among 16 newborn C57BL/6J (B6) mice, three were positive for the IL-4 transgene. Serum IL-4 levels of transgenic versus control B6xC3H F1 mice were not statistically different. Reverse-transcriptase polymerase chain reaction showed that the transgenic B6xC3H F1 mice expressed IL-4 mRNA in the heart and in the lung, whereas control mice did not express IL-4 in any organ. IL-4 mRNA expression in the transgenic but not in the control heart was also confirmed by RNAse protection assay and fluorescence in situ hybridization. The survival of IL-4 transgenic B6xC3H heart grafts heterotopically placed in C3H recipients was prolonged compared with that of nontransgenic grafts (19.0+/-9.1 vs. 6.8+/-2.2 days, P=0.003). Interferon-gamma mRNA expression in IL-4 transgenic heart grafts on the fifth posttransplant day as assessed by Northern blotting was suppressed compared with that in control grafts. Reverse-transcriptase polymerase chain reaction analysis showed that IL-2 mRNA was suppressed in the IL-4 transgenic grafts compared with that in control grafts, while IL-4 mRNA was observed only in IL-4 transgenic grafts. IL-10 mRNA was detected at similar levels in both transgenic and control grafts. CONCLUSIONS: A Th2 bias may contribute to allograft acceptance in part by inducing the down-regulation of Th1-cytokine mRNAs, but it may not be sufficient to induce indefinite graft survival.

Animals↗

PubMed1997

Inhibition of thymocyte apoptosis by berberine.

To find anti-apoptotic substances in plant resources, a microassay method for estimating DNA fragmentation was established using fluorochrome 3,5-diaminobenzoic acid dihydrochloride. Examination was made of various herbal medicines for inhibitory effects on glucocorticoid-induced apoptosis in thymocytes. Several Kampo medicines, e.g. Oren-gedoku-to and San'o-shashin-to, were found to inhibit dexamethasone-induced apoptosis in murine thymocytes. Some of these medicines contain Coptidis rhizoma (CR) as the major constituent, and the CR extract showed the most potent inhibitory activity on thymocyte apoptosis of more than 200 species of herbal extracts. The inhibition of apoptosis by CR extract was confirmed by the trypan blue exclusion test, lactate dehydrogenase release measurement, and morphological evaluation by electron microscopy. The benzodioxolo-benzoquinolizine alkaloid, berberine, and five berberine-type alkaloids, isolated from CR extract, had an inhibitory effect, whereas no effect was noted for the aporphin-type alkaloid magnoflorine. The inhibitory action of berberine was also demonstrated on etoposide- and camptothecin-induced apoptosis.

Animals↗

PubMed1997

Expression of hepatocyte growth factor and its receptor, the c-met proto-oncogene, in hepatocellular carcinoma.

The c-met proto-oncogene encodes the tyrosine kinase receptor for hepatocyte growth factor (HGF), a potent mitogen and motogen for epithelial cells. Because of its profound effects on cell growth and motility, HGF may be important in the development of cancer metastases in hepatocellular carcinoma (HCC). In this study, we examined HGF concentration and expression of the c-met proto-oncogene product (c-Met) in 62 patients with HCC to determine the relationship between the level of expression and clinicopathological features, and patient outcome following hepatectomy. Western blotting was used to examine the c-Met expression, and HGF concentration in tumors was measured using an enzyme-linked immunosorbent assay. c-Met was found to be overexpressed in HCC compared with nontumorous liver tissue (P < .01), and correlated with an increased incidence of intrahepatic metastases (P = .039). Patients were divided into two groups: low c-Met HCC and high c-Met HCC. Patients with high c-Met HCC had a significantly shorter 5-year survival than patients with low c-Met HCC (33.5% vs. 80.3%, respectively; P < .05). However, there was no correlation between HGF concentration in the tumor tissue and clinicopathological factors and patient survival. These results indicate that the expression of c-Met played an important role in tumor growth and metastases in patients who underwent hepatectomy for HCC.

Adult↗

PubMed1997

Expression of hepatocyte growth factor and its receptor c-met proto-oncogene in hepatocellular carcinoma.

The c-met proto-oncogene encodes the tyrosine kinase receptor for hepatocyte growth factor (HGF), a potent mitogen and motogen for epithelial cells. Because of its profound effects on cell growth and motility, HGF may be important in the development of cancer metastases in hepatocellular carcinoma (HCC). In this study, we examined HGF concentration and expression of the c-met-proto-oncogene product (c-met) in 62 patients with HCC to determine the relationship between the level of expression and clinicopathological features, and patient outcome following hepatectomy. Western blotting was used to examine the c-met expression, and HGF concentration in tumors was measured using an enzyme-linked immunosorbent assay. c-met was found to be overexpressed in HCC compared with nontumorous liver tissue (P < .01), and correlated with an increased incidence of intrahepatic metastases (P = .039). Patients were divided into two groups, low c-met HCC and high c-met HCC. Patients with high c-met HCC had a significantly shorter 5-year survival than patients with low c-met HCC (33.5% vs. 80.3%, respectively; P < .05). However, there was no correlation between HGF concentration in the tumor tissue and clinicopathological factors and patient survival. These results indicate that expression of c-met played an important role in tumor growth and metastases in patients who underwent hepatectomy for HCC.

Adult↗

PubMed1997

Lymphoepithelial cyst of the pancreas.

A case of lymphoepithelial cyst (LEC) of the pancreas is presented. A 48-year-old man complaining of general fatigue was found to have a heterogeneous water-dense mass protruding from the surface of the pancreas on plain computed tomography (CT). Dynamic CT disclosed septa within the mass. Magnetic resonance imaging, (MRI) showed a hypointense mass on T1-weighted imaging, and a hyperintense mass on T2-weighted imaging. MRI with gadolinium enhancement revealed septa within the mass. Endoscopic ultrasonography showed septa and fine echogenic structures within the cystic echoic lesion. Endoscopic retrograde pancreatography showed a normal duct system. Distal pancreatectomy with splenectomy was performed, with a suspected diagnosis of cystic neoplasms of the pancreas. Histopathologic examination disclosed LEC of the pancreas. Our case suggests that LEC should be considered in the differential diagnosis of cystic neoplasms of the pancreas.

Cholangiopancreatography, Endoscopic Retrograde↗

PubMed1997

Th2-like response and antitumor effect of anti-interleukin-4 mAb in mice bearing renal cell carcinoma.

Tumor regression in experimental systems has been linked to the activities of Th1 cells. It is, therefore, conceivable that Th2 cells interrupt the expression of tumor immunity since interleukin-4 (IL-4) and IL-10 inhibit the generation of Th1 from precursors and modulate the competence of antigen-presenting cells to activate this lymphocyte subpopulation. Naive murine renal cell carcinoma (renca) cells (1 x 10(5)) were implanted into the subcapsule of the left kidney of Balb/c and Balb/c nude mice at 6-8 weeks of age. After 14 days, Th2 cytokine (IL-4 and IL-10) mRNAs as well as transforming growth factor beta1 mRNA, assessed by reverse transcriptase/polymerase chain reaction were upregulated in the spleen of hosts upon naive renca tumor acceptance, while Th1 cytokine (IL-2 and interferon gamma) mRNAs were almost undetectable. In the renca tumor, IL-10 mRNA was detected but IL-2, interferon gamma, and IL-4 were not. Intraperitoneal administration of anti-(mouse IL-4) mAb (11B11) reduced the renca tumor size (P = 0.018) and prolonged host survival (P = 0.03), but did not reduce the acceptance rate of the tumor (P = 0.18). However, prior depletion of CD4+ or CD8+ cells with monoclonal antibodies abrogated the antitumor effects of anti-IL-4 mAb. In addition, the significant antitumor effect of anti-IL-4 mAb was not observed in Balb/c nude hosts. Renca cells were transfected with the mammalian expression vector pCAGGS containing murine IL-4 cDNA or vector alone, then stable IL-4 transfectants (RencaL or RencaH, low- or high-IL-4-producing respectively) and control renca cells (RencaC) were obtained. RencaL cells, RencaH cells, or RencaC cells (1 x 10(5) each) were implanted into the subcapsule of the left kidney of Balb/c, Balb/c nude, and allogenic C3H/HeJ mice, then tumor formation was evaluated 14 days later. When RencaH cells were innoculated into syngeneic Balb/c hosts, tumor volume was marginally suppressed (P = 0.03) and tumors tended to be rejected (P = 0.06) compared with RencaC cells. However, those effects were not observed in Balb/c nude mice. RencaC, RencaL, and RencaH cells were not accepted by allogeneic C3H mice with or without FK506 administration or donor-specific transfusion. The administration of anti-(mouse IL-4) mAb to Balb/c mice significantly suppressed renca tumor growth by a CD4+ and CD8+ T-cell-dependent mechanism. By contrast, relatively high levels of IL-4 production by renca cells and T cells seemed to be required to induce the rejection and growth suppression of IL-4-producing renca cells in syngeneic hosts.

Animals↗

PubMed1997

Significance of the expression of proliferation-associated nucleolar antigen p120 in human colorectal tumors.

Nucleolar protein p120 is considered to be associated with cell proliferation and has also been detected in a broad range of human malignant cells and tissues, but not in either normal resting tissue or most benign tumors. To clarify the significance of the expression of p120 in colorectal tumors or to evaluate the contribution of p120 in the development of colorectal carcinoma, the authors developed a monoclonal antibody against p120 and then examined its expression in adenoma, carcinoma, and normal mucosa. In adenomas, p120 expression was shown in none of 13 cases of mild dysplasia (0%), 2 of 15 of moderate dysplasia (13.3%), and in 2 cases of severe dysplasia (100%). p120-positive adenomas of moderate dysplasia tended to be larger and had higher Ki-67 indexes than the negative ones (adenomas of moderate dysplasia). All 27 carcinomas were positive for p120. p120 immunostaining was found in the nuclei and corresponded closely to the prominent nucleoli of tumor cells. In contrast, either weak or the occasional expression of p120 was traced in only one of the nine normal mucosae (11.1%). Three of the transitional mucosae of the carcinoma were also positive for p120. The percentage of p120-positive tumor cells (p120 index) ranged from 3.2% to 86.6%, and the mean p120 indexes of the four adenomas and all carcinomas were 21.3% and 41.5%, respectively. The p120 index was significantly related to the Ki-67 index (P < .001) in the p120-positive tumors, whereas the p120 index of the carcinoma did not significantly correlate to the known prognostic markers, such as tumor size, stage, or the degree of differentiation. These results thus suggest that the expression of p120 serves as a marker for cells with a high proliferative potential and is linked to the late events of colorectal tumor progression.

Adenoma↗