Biomedical subjects

T Nagasaka

Publications and source records attributed to T Nagasaka.

At least 73 records · Page 4Linked to original sources

PubMed2000

The expression and localization of neutral endopeptidase 24.11/CD10 in human gestational trophoblastic diseases.

Neutral endopeptidase 24.11 (NEP)/CD10 is a cell-surface peptidase that hydrolyzes various bioactive peptides. NEP is distributed in both normal and neoplastic cells and plays a functional role by modulating cellular responses to peptide substrates. Recently, NEP has been shown to be expressed in normal placental trophoblasts, suggesting its physiological role during pregnancy. In the present study, we investigated the expression of NEP in hyperplastic and anaplastic trophoblasts in gestational trophoblastic diseases (GTDs). Flow cytometric analysis demonstrated that NEP was expressed in all choriocarcinoma cell lines examined. The NEP enzyme activity in these cell lines correlated with cell-surface protein levels and was abolished by the NEP inhibitor phosphoramidon. On immunoblot analysis, NEP protein was detected in both hydatidiform mole and choriocarcinoma tissues as a double band of 95 and 100 kDa similar to that of the normal placental tissues. Immunohistochemical analysis revealed that NEP was present on syncytiotrophoblasts, while no or very faint NEP immunoreactivity was observed on cytotrophoblasts in the normal placenta. Similarly, NEP in hydatidiform mole and invasive mole was localized on the membrane of syncytiotrophoblasts, but not on hyperplastic cytotrophoblasts. In contrast, in choriocarcinoma, NEP was highly expressed not only on syncytiotrophoblastic cells but also on invading anaplastic cytotrophoblasts. In addition, NEP was also expressed on intermediate trophoblasts in placental site trophoblastic tumors. In summary, this is the first study demonstrating the expression of NEP/CD10 in GTDs. The differential localization of NEP among various trophoblastic tumors suggests that NEP may play a functional role in the regulation of trophoblast transformation and human chorionic gonadotropin secretion.

Blotting, Western↗

PubMed2000

Association of SYT-SSX fusion types with proliferative activity and prognosis in synovial sarcoma.

The t(X;18)(p11.2;q11.2) translocation commonly found in synovial sarcoma (SS) results in the fusion of the SYT gene on chromosome 18 to either of two closely related genes, SSX1 and SSX2, on chromosome X. It has been suggested that patients who have SS bearing SYT-SSX1 fusion have worse prognosis than those bearing SYT-SSX2 fusion. However, little is known about the biologic basis or the relationship with the histopathologic risk factors in regard to the different fusion types. We analyzed 19 cases of SS with no metastasis at diagnosis. These tumors were classified by reverse transcription-polymerase chain reaction to SYT-SSX1 and SYT-SSX2 types. The expression of Ki-67, p27, p53, and bcl-2 and various clinicopathologic parameters including mitotic rate were compared between the two fusion types. The SYT-SSX1 type fusion was associated with high Ki-67 expression (P = .011) and high mitotic rate (P = .070). No significant differences were found between the two types as to the expression of p27, p53, and bcl-2 and other clinicopathologic parameters. The survival analysis showed that SYT-SSX1-type fusion, high Ki-67 expression, and high mitotic rate correlated with shorter metastasis-free survival. These data suggested that SYT-SSX fusion type is associated with tumor cell proliferative activity and prognosis of patients who have SS.

Adolescent↗

PubMed2000

Anaplastic large cell lymphomas presented as bone lesions: a clinicopathologic study of six cases and review of the literature.

Non-Hodgkin's lymphomas uncommonly present as bone lesions. Most of these tumors are diffuse large B-cell lymphomas. Anaplastic large cell lymphoma (ALCL) presented as bone lesions is exceedingly rare. In this study, we describe six cases of ALCL that presented as solitary or multiple bone lesions. The average patient age was 33 years (range, 4 to 63 years) and the male to female ratio was 2:1. Fever and localized bone pain were the most frequent presenting symptoms. Radiologic examinations revealed osteolytic lesions in all cases, with three (50%) being multiple lesions and five (83%) involving the axial bones. All patients were initially assessed to have only bone involvement. Staging studies revealed mild cervical lymphadenopathy in one patient and no evidence of extraskeletal disease in the other five patients. Histologically, there was diffuse infiltration of one or more bones by large pleomorphic lymphoma cells. Immunohistochemical studies showed all six neoplasms were positive for CD30, EMA, and granzyme B. One case was of T-cell lineage, positive for CD3. One case was positive for the T-cell-associated antigen CD4. The remaining four cases were of null-cell type. In-situ hybridization for EBV was performed in five cases; all were negative. Despite the relatively low International Prognostic Index (IPI) of these patients (mean, 1.67; range, 1 to 3), the overall prognosis was relatively poor: three of six died of disease within 2 years of diagnosis, and two of six were alive with evidence of disease (follow-up, 6 mo to 2 years). Thus, compared to their nodal counterparts, ALCLs that present as bone lesions are distinguished by their uniform expression of EMA and granzyme B, and a relatively poor clinical outcome. Our results also suggest that ALK-1 expression in this clinical setting is not a favorable prognostic indicator.

Adult↗

PubMed2000

Protean manifestations of lipoid proteinosis in a 16-year-old boy.

We report a 16-year-old Japanese male with lipoid proteinosis showing various skin manifestations. The patient was born to nonconsanguineous parents and none of his relatives was similarly affected. The patient suffered from a hoarse voice and refractory temporal epilepsy from early childhood. Computed tomography scanning of the brain showed bilateral calcification in the temporal lobes, a characteristic feature of lipoid proteinosis. On physical examination, various skin manifestations, including papules and haemorrhagic blisters, acne-like scars at sites of minor trauma or friction, and beads of small papules along the free margins of the eyelids were noted. A skin biopsy showed deposits of homogeneous hyaline-like material, positive on periodic acid-Schiff staining, throughout the dermis, particularly around small blood vessels. It is noteworthy that a range of characteristic skin lesions can be present in a patient with lipoid proteinosis even with mild systemic involvement.

Adolescent↗

PubMed2000

Expression of aminopeptidase A in human gestational choriocarcinoma cell lines and tissues.

Aminopeptidase A (AP-A), a cell-surface metallopeptidase hydrolyzing peptide with N-terminal acidic residues, has been proved to be identical to the B cell differentiation antigen BP-1 and to the kidney differentiation antigen gp160, suggesting recognition of AP-A as a differentiation-related marker on certain normal and transformed cells. AP-A has also been purified from human placenta and been shown to be localized in the trophoblasts. In the present study, we examined the expression and enzymatic activity of AP-A in human gestational choriocarcinoma, a neoplastic transformant from trophoblasts which comprises a heterogenous population of trophoblastic cells in different stages of differentiation. Flow cytometry and immunoblot analysis demonstrated that AP-A was expressed in five choriocarcinoma cell lines which were secreting low or moderate levels of human chorionic gonadotropin (hCG), while two high hCG-secreting cell lines lacked AP-A expression. The AP-A enzymatic activity correlated with cell-surface levels of AP-A and was abrogated by amastatin, an inhibitor of AP-A. Immunohistochemical analysis revealed that AP-A was present in seven of eight choriocarcinoma tissues and was localized on the cell membrane of cytotrophoblastic choriocarcinoma cells, but not on cells with syncytiotrophoblast-like features. These results demonstrate that AP-A is expressed on most choriocarcinomas and its expression is restricted to low hCG-secreting, cytotrophoblastic cells and down-regulated as a function of cell differentiation, suggesting an involvement of AP-A in the differentiation/maturation process of neoplastic trophoblasts.

Amino Acid Sequence↗

PubMed2000

Placental aminopeptidase A as a possible barrier of angiotensin II between mother and fetus.

Aminopeptidase A (AP-A EC 3.4.11.7), which is a membrane-bound zinc metalloprotease, is present in the placenta. AP-A selectively hydrolyzes N-terminal glutamyl and aspartyl residues and cleaves angiotensin II to form angiotensin III. To determine the role of placental aminopeptidase A under physiological and pathological conditions, we evaluated its immunolocalization and enzymatic activities in the placenta. AP-A was localized in the basal zone of the syncytiotrophoblast, in the membranes of the cytotrophoblast, and in fetal arterioles and venules within the stem villi. AP-A activity in the microsomal fraction of placental villi seemed to be remained essentially constant throughout gestation. The renin-angiotensin system is considered to be accelerated in pre-eclampsia. This AP-A activity was higher in pre-eclampsia (2.86+/-0.30 nmol beta NA/mg protein/h) than in uncomplicated pregnancy from 28 to 41 weeks of gestation (2.08+/-0.18 nmol beta NA/mg protein/h). Angiotensin II evoked AP-A activity in first trimester trophoblast, and Losartan and PD 123177 in combination significantly inhibited this induction of AP-A activity. The results of immunohistochemical evaluation and enzymatic activity suggested that placental aminopeptidase A may play a role as a component of the barrier of angiotensin II between mother and fetus.

Adult↗

PubMed2000

A concise overview of recent breakthroughs in imaging of ALS.

Numerous attempts have been made to visualize the motor cortex and pyramidal tract lesions in patients with ALS using magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT) and positron emission tomography (PET). This paper briefly reviews the applicability of these imaging modalities in ALS.

Amyotrophic Lateral Sclerosis↗

PubMed2000

Elucidation of vascular structure of molar villi in complete hydatidiform mole by CD-34 antibody.

Vasculature was examined immunohistochemically in the villous stroma in 22 cases of complete hydatidiform mole (CHM). Only antibody CD-34 was able to detect the vasculature. Serial thin and thick sections and squashed preparations of molar villi were stained by CD-34, and sequential photographs of the vasculature were taken and projected on paper, and the vasculature was described and reconstructed. In the stroma of almost all molar villi examined, vessels were found, but their density and structure varied greatly in each molar villus even in the same CHM, and the vessels were irregular in diameter. In fully distended molar villi the vessels often became narrow, continuing like a broken line but eventually vanishing. Generally the density of the vessels was inversely proportional to the grade of the swelling of villi. The vessels sometimes passed through two adjacent molar vesicles. No significant differences in vasculature were found in molar villi at different gestational ages.

Adult↗

PubMed2000

Human cerebellum plays an important role in memory-timed finger movement: an fMRI study.

The purpose of this study was to determine, by using functional magnetic resonance imaging, the areas of the brain activated during a memory-timed finger movement task and compare these with those activated during a visually cued movement task. Because it is likely that subjects engage in subvocalization associated with chronometric counting to achieve accurate timing during memory-timed movements, the authors sought to determine the areas of the brain activated during a silent articulation task in which the subjects were instructed to reproduce the same timing as for the memory-timed movement task without any lip movements or vocalization. The memory-timed finger movement task induced activation of the anterior lobe of the cerebellum (lobules IV and V) bilaterally, the contralateral primary motor area, the supplementary motor area (SMA), the premotor area (PMA), the prefrontal cortex, and the posterior parietal cortex bilaterally, compared with the resting condition. The same areas in the SMA and left prefrontal cortex were activated during the silent articulation task compared with the resting condition. The anterior lobe of the cerebellum on both sides was also activated during the silent articulation task compared with the resting condition, but these activations did not reach statistical significance (P < 0.05 corrected). In addition, the anterior cerebellum on both sides showed significant activation during the memory-timed movement task when compared with the visually cued finger movement task. The visually cued finger movement task specifically activated the ipsilateral PMA and the intraparietal cortex bilaterally. The results indicate that the anterior lobe of the cerebellum of both sides, the SMA, and the left prefrontal cortex were probably involved in the generation of accurate timing, functioning as a clock within the CNS, and that the dorsal visual pathway may be involved in the generation of visually cued movements.

Adult↗

PubMed2000

Phenotypic variation of familial hypertrophic cardiomyopathy caused by the Phe(110)-->Ile mutation in cardiac troponin T.

Mutation of the cardiac troponin T (cTnT) gene is a genetic determinant of familial hypertrophic cardiomyopathy (HCM). A Japanese family of 14 individuals, including 6 with HCM, was subjected to genetic and clinical assessment. Five exons of the cTnT gene were sequenced in all family members. A heterozygous or homozygous T(340)-->A (Phe(110)-->Ile) mutation in exon 9 of the cTnT gene was detected in 11 subjects. Morphological and functional evaluation of the left and right ventricles by echocardiography revealed that 4 of 9 individuals heterozygous for the mutant allele exhibited HCM with moderate cardiac hypertrophy. Cardiac hypertrophy and other clinical features in the 2 subjects homozygous for the mutation were more severe than were those in heterozygous individuals with HCM. Thus, the clinical features of HCM due to the Phe(110)-->Ile mutation in the cTnT gene appear to be modified by a gene dosage effect.

Adolescent↗

PubMed2000

Aminopeptidase A expression in cervical neoplasia and its relationship to neoplastic transformation and progression.

Aminopeptidase A (AP-A) is a cell surface metallopeptidase which specifically cleaves the amino-terminal acidic residue from peptide substrates such as angiotensin II. AP-A is identical to the differentiation-related antigen, murine BP-1 or human kidney gp160, and is involved in regulating cell differentiation and/or neoplastic transformation of certain normal and transformed cells. We examined expression of AP-A in premalignant and malignant lesions of the uterine cervix, and investigated whether its expression was related to disease progression and neoplastic transformation. Formalin-fixed, paraffin-embedded tissue sections including 14 cervical intraepithelial neoplasms (CIN) and 23 invasive squamous cell carcinomas (SCC) were immunohistochemically evaluated. AP-A was localized in the basal cell layer in normal squamous epithelium. In CIN, AP-A expression was found on dysplastic cells, and increased with the severity of the precancerous lesions. In invasive cancer, 18 of 19 non-keratinizing-type SCCs and none of 4 keratinizing-type SCCs expressed AP-A. In addition, AP-A immunoreactivity was significantly correlated with proliferating cell nuclear antigen expression in both CIN and SCC cases. Furthermore, angiotensin II type 1 receptor was present in all AP-A-positive SCCs. These results indicate that AP-A is upregulated as the lesion progresses toward carcinoma in the cervical epithelium, and suggest that AP-A may play a regulatory role in neoplastic transformation and disease progression in cervical neoplasms and may serve as a potential tumor marker during cervical neoplasia development.

Adult↗

PubMed2000

Oxytocin stimulates the translocation of oxytocinase of human vascular endothelial cells via activation of oxytocin receptors.

Oxytocinase (OTase) degrades several small peptides such as oxytocin (OT), and thus plays important roles in fetal development and maintenance of human homeostasis during pregnancy. The physiological effects of OT are mediated via its receptor (OTR). Although the interactions between OT and OTR have studied extensively, the relationship to OTase remains to be clarified. It is known that human umbilical vascular endothelial cells express OTR messenger RNA; therefore, they were selected for examination of this question in the present study. RT-PCR experiments confirmed the existence of messenger RNA for OTase, and assessment of protein levels and activity clarified that OT increases the activity of OTase at the cell surface via binding to OTR. This stimulation appears to involve translocation of OTase from cytosolic to the cell surface in response to cellular signal transduction pathways linked to the OTR. Protein kinase C stimulation significantly increased the cell surface activity of OTase, whereas its inhibition resulted in reduction. In summary, our findings provide clear evidence that OT triggers directly OTase translocation in human umbilical vascular endothelial cells via a protein kinase C-dependent pathway coupled to OTR.

Biological Transport↗

PubMed2000

Sarcomatous transformation of a prolactinoma associated with development of a fatal internal carotid artery pseudoaneurysm--case report.

A 21-year-old female with a 5-year history of prolactinoma was referred to our hospital because of cerebrospinal fluid leakage and meningitis immediately following a third transsphenoidal operation for a rapidly growing tumor. Histological examination of the tumor removed at the second transsphenoidal operation found atypical epithelial and sarcomatous components. Administration of bromocriptine, radiotherapy, and chemotherapy were initiated. Emergent craniotomy was required for rapid regrowth of the tumor. Histological examination found predominant sarcomatous components. Tumor growth was difficult to control. The patient died of subarachnoid hemorrhage due to rupture of a pseudoaneurysm involving the C1 portion of the right internal carotid artery. Pituitary adenoma rarely shows malignant transformation. In this case, prolactinoma underwent malignant change to sarcoma. Development of the pseudoaneurysm may have resulted from surgical manipulation, radiotherapy, or tumor invasion.

Adult↗

PubMed2000

Midkine expression in Reed-Sternberg cells of Hodgkin's disease.

Midkine (MK) was originally cloned as a product of a retinoic acid-responsive gene. The rationale for studying MK expression is based on previous reports showing that it transforms 3T3 cells, and that it acts as an autocrine growth factor in Wilm's tumors, and that its overexpression has been associated with worse outcome in bladder carcinoma. Besides bladder carcinoma, its expression was reported in various solid tumors. We investigated the expression of MK protein and/or MK gene in biopsied specimens from 40 patients with primary malignant lymphoma, 21 with Hodgkin's disease (HD) and 19 with non-Hodgkin's lymphoma (NHL). Reed-Sternberg (R-S) cells were stained positive in 10 of 16 HD cases evaluated by immunohistochemical method, whereas 18 of 19 NHL cases did not stain, and one B-cell NHL stained weakly positive. Immunostaining analysis was extended to established cell lines and to normal lymphocytes with or without lectin stimulation or with EB virus transformation. Among hematopoietic cells examined, erythro- or megakaryoblastic leukemia cell lines (K562, MEG-01 and UT7) were positive, while normal lymphocytes (except the EB virus-transformed one) and most myeloid and lymphoid cell lines (except Raji cells) were negative. On the contrary, solid tumor cell lines showed high and strongly positive staining including cell lines derived from of lung gastric, colon, and a pancreatic cancer. Using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), which is suitable for the detection of weakly expressed mRNA, the relative ratio of MK mRNA to beta-actin mRNA of samples was measured and compared in cases where RNA was available. The mean values of relative ratio (MK/beta-actin) of HD were almost twice as those of NHL samples, peripheral blood T cells, and spleen B cells. Our findings showed that MK is expressed in Reed-Sternberg cells of HD, and that MK might play a role in the pathogenesis of HD.

Animals↗

PubMed2000

The use of archival bone marrow specimens in detecting B-cell non-Hodgkin's lymphomas using polymerase chain reaction methods.

The detection of B-cell non-Hodgkin's lymphoma (B-NHL) involving the bone marrow (BM) can be enhanced by assessing immunoglobulin heavy chain (IgH/JH) gene rearrangement using PCR. While the fresh BM aspirate has been the most commonly used specimen, the utility of archival BM tissues has not been extensively evaluated. We studied the BM from 13 patients with nodal B-NHL (7 low-grade and 6 intermediate grade), which were categorized into three groups based on the histologic finding of lymphoma (H) and the presence of a monoclonal IgH/JH band by PCR using fresh BM aspirates (M): (1) H(+)/M(+), 4 cases; (2) H(+)/M(-), 4 cases; and (3) H(equivocal)/M(-), 5 cases. Archival tissues available for study included paraffin-embedded trephine biopsy (TB)/aspirate clots (AC) and air-dried aspirate smears (AS). All TB (13/13) and a subset of AC (5/13) were B5-fixed, and all these tissues failed to yield analyzable DNA. In contrast, sufficient DNA was consistently obtained in AC that were formalin-fixed (8/13). Of these 8 cases, 2/3 of group 1, 3/3 of group 2, and 0/2 of group 3 had a monoclonal IgH band. Using DNA extracted from microdissected lymphoid aggregates morphologically evident in the AC sections, additional positive cases were identified: 1/3 of group 1 and 2/2 of group 3. In those 5 cases that did not have formalin-fixed TB/AC, sufficient DNA was extracted from AS in all cases; one additional positive case was identified in group 1. Overall, 4/4 (100%) of group 1, 3/4 (75%) of group 2, and 2/5 (40%) of group 3 showed molecular evidence of lymphoma. To conclude, archival BM specimens are a useful source of DNA for molecular detection of B-NHL involvement, and formalin appears to be a better fixative than B5. The use of these samples may improve the overall detection sensitivity.

Adult↗

PubMed2000

Coexisting thymic and gastric lymphomas of mucosa-associated lymphoid tissues in a patient with Sjögren syndrome.

Lymphomas of mucosa-associated lymphoid tissues (MALTomas) arising from the thymus are extremely rare. In this case report, we describe a 36-year-old woman with an 11-year history of Sjögren syndrome who was found to have a thymic MALToma coexisting with a gastric MALToma. Both tumors shared similar histologic features, showing clusters of centrocytic-like B cells, lymphoepithelial lesions, and prominent plasmacytic differentiation. They also showed the following identical immunohistochemical features: CD20(+), IgA/lambda(+), CD5(-), and CD43(-). Molecular studies using polymerase chain reaction methods revealed monoclonal gene rearrangement of the immunoglobulin heavy chain in the gastric MALToma, but not in the thymic MALToma. The possible pathogenesis of this unusual case is discussed.

Adult↗

PubMed2000

Glandular malignant peripheral nerve sheath tumor: an unusual case showing histologically malignant glands.

In this report, we describe a highly unusual case of glandular malignant peripheral nerve sheath tumor presenting as a neck mass in a previously healthy 29-year-old man. Grossly, the tumor was found to arise from a swollen peripheral nerve trunk. The tumor was largely composed of spindle cells that demonstrated marked nuclear pleomorphism and numerous abnormal mitotic figures. In addition, histologically malignant glandular structures lined by simple nonciliated columnar cells with goblet cells were found clustered in the center of the tumor. Examination of the swollen peripheral nerve trunk revealed the presence of a plexiform neurofibroma. The spindle cells were positive for S100. The glands were negative for S100 but positive for keratin, epithelial membrane antigen, and neuroendocrine markers (somatostatin, chromogranin, Leu-7, and calcitonin). This patient was subsequently diagnosed as having von Recklinghausen disease and died of tumor metastasis to the lungs 34 months after the presentation. To our knowledge, only 3 similar cases have been previously described in the literature.

Adult↗

PubMed2000

PGP9.5 as a prognostic factor in pancreatic cancer.

The expression of PGP9.5 was evaluated using immunohistochemistry in 69 resected ductal carcinomas of the pancreas and in normal pancreatic tissue. Overexpression did not seem to differ with histological type or pathological stage. A significant negative correlation was found between overexpression of PGP9.5 and postoperative survival. Multivariate analysis also suggested PGP9.5 along with tumor stage and extrapancreatic plexus invasion as strong predictors of the outcome. This study suggests that PGP9.5 expression may be used as a marker for predicting the outcome of resection-treated pancreatic cancer patients.

Adenocarcinoma↗