Biomedical subjects

S Nakamura

Publications and source records attributed to S Nakamura.

At least 37 records · Page 2Linked to original sources

PubMed2006

Expression of tumor-associated antigen RCAS1 and its possible involvement in immune evasion in oral squamous cell carcinoma.

BACKGROUND: RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is known to induce apoptosis in its receptor-positive cells. The authors investigated RCAS1 expression in oral squamous cell carcinoma (SCC) and its association with the apoptosis of tumor-infiltrating lymphocytes (TILs). METHODS: In 130 patients with oral SCC, the expression of RCAS1 in tumor cells was immunohistochemically examined and the apoptosis of TILs was examined by Terminal Deoxynucleotidyltransferase-mediated dUTP Nick End Labeling (TUNEL) staining. RESULTS: RCAS1 was detected both on the cytoplasm and the membrane of tumor cells in 41 of 130 cases (31.5%). Focusing on the expression at the invasive front interacting with host immune cells, RCAS1 was detected in 22 of 130 cases (16.9%). The percentage of TUNEL-positive TILs in cases with RCAS1-positive SCCs was significantly higher than in cases with RCAS1-negative SCCs (P < 0.0001). CONCLUSIONS: RCAS1 can be expressed on oral SCC cells and may be involved in the tumor escape from the host immune system by inducing the apoptosis of TILs.

Aged↗

PubMed2006

Pedunculated oncocytic carcinoma in buccal mucosa: immunohistochemical and ultrastructural studies.

PURPOSE: In this study we evaluated pedunculated oncocytic carcinoma (OC) in the buccal mucosa via immunohistochemical and ultrastructural studies. PATIENT AND METHODS: An 84-year-old man was referred to our clinic with a pedunculated mass about 4 cm in diameter in the right buccal mucosa. An incision biopsy revealed the diagnosis of oncocytic tumor, and enucleation was performed. The tumor was stained for immunohistochemical analysis using the ABC method and antibodies against cytokeratin (CK), epithelial membrane antigen (EMA), desmin, S-100 protein and muscle-specific actin, respectively. The tumor was stained with uranyl acetate and lead citrate for visualization by electron microscopy. RESULTS: Histopathology results revealed that the tumor consisted of oncocytic cells, characterized by eosinophilic and granular cytoplasm, and atypical nuclei. These cells had infiltrated local blood vessels, salivary glands and muscles. Immunohistochemical staining indicated that these cells were positive for CK and EMA, and negative for desmin, muscle-specific actin and S-100 protein. Electron microscopy revealed numerous dilated cytoplasmic mitochondria, and the cell contours and nucleic shapes of tumor cells were often irregular. CONCLUSIONS: Because the histopathologic features of OC are similar to those of benign oncocytoma, the diagnosis of OC must be confirmed by a combination of clinical and ultrastructural characteristics.

Adenocarcinoma↗

PubMed2006

Establishment of a GIS monitoring system for schistosomiasis japonica in Kofu, Japan.

Although the incidence of human infection with Schistosoma japonicum in Japan fell to zero in 1977, the threat of the possible re-emergence of the disease caused by this trematode still exists. Surveillance of the parasite's intermediate host, Oncomelania nosophora, in Kofu basin therefore began in 1996. A simple, new method for monitoring O. nosophora in an at-risk area in Kofu, which is based on a geographical information system (GIS), was established. At each monitoring site (of which there were 120 from 1996 until 2000, and 60 from 2001 until 2003), the O. nosophora in two quadrats, each measuring 25 x 25 cm, were collected. During the study, the exact location of each site was determined using a hand-held global-positioning system (GPS). This allowed all the sites to be digitally mapped, so that anyone with a hand-held GPS could and can reach each site. The snail and location data were processed using commercial GPS/GIS software packages and used to create a risk map for schistosomiasis re-emergence. Although all snails collected between 1996 and 2003 were uninfected, the proportion of investigated sites in which O. nosophora was detected increased from 36.7% in 1996 to 56.7% in 2003. The mean number of O. nosophora collected per snail-positive site fluctuated widely, between 8.2 and 57.4, in each calendar year. Over the study period there appeared to be a shift southwards in the areas with high densities of O. nosophora. The present results indicate that it is possible to utilize a GIS-based method for the long-term monitoring of the possible re-emergence of schistosomiasis japonica in Japan.

Agriculture↗

PubMed2006

Primary chondrosarcoma in the liver of a dog.

Primary chondrosarcoma was found in the quadrate lobe of the liver of a 6-year-old, intact, male Golden Retriever. At 6 months after partial hepatectomy, recurrence in the liver occurred. The dog died of its systemic metastases 10 months thereafter. Histologically, the hepatic mass revealed neoplastic chondrocytes with abundant chondroid matrix, and there were few myxoid areas where the cellularity and pleomorphism of the neoplastic cells were more prominent. The neoplastic cells were positive for periodic acid-Schiff and were immunohistochemically positive for vimentin and S-100 protein; the matrix was deeply stained for alcian blue and was metachromatic for toluidine blue stain. This tumor might be derived from pluripotent mesenchymal cells in the connective tissue of the liver. To the best of our knowledge, in all mammalians, including humans, this is the first report of extraskeletal chondrosarcoma primarily arising in the liver.

Animals↗

PubMed2006

Microalbuminuria and deterioration of renal function after elective repair of infrarenal abdominal aortic aneurysm.

AIMS: Renal dysfunction affects the prognosis of patients after aortic surgery. However, the factors associated with the postoperative deterioration of renal function has not been clarified precisely. METHOD: We prospectively examined renal function in 80 patients (age: 73 +/- 7 years, 66 males) who required the elective repair of infrarenal abdominal aortic aneurysm (AAA). Serum creatinine (Scr) was measured. 24-h-creatinine clearance (Ccr) and urinary albumin excretion (UAE) were determined. Renal volume and mean renal length were calculated using the data obtained by ultrasonography. 48 patients showed normal UAE (< 30 mg/day), and 24 had microalbuminuria (30-300 mg/day) and 8 had overt proteinuria (> 300 mg/day). Scr were 0.9 +/- 0.4, 1.0 +/- 0.3 and 2.1 +/- 1.3 mg/dl, respectively. RESULTS: On Day 5 after surgery, 12 patients (15%) showed deterioration of renal function as defined either by an increase in Scr (> or = 0.5 mg/dl) or by a decrease in Ccr > or =20%). The acute deterioration of renal function was related to mean renal volume, mean renal length, duration of operation and the use of antibiotics. At Month 12 after surgery, Scr increased in the overt proteinuria group. The deterioration of renal function at Month 12 was found in 8 patients (10%) with microalbuminuria or overt proteinuria, and related to preoperative Ccr, UAE, mean renal volume, mean renal length, smoking status and blood pressure. CONCLUSION: We conclude that the deterioration of renal function occurred in considerable number of patients with AAA after elective operation on acute and chronic phase, although the development of end-stage renal failure is rare. Factors related to the acute and late deterioration appears to be different. UAE and renal size should be measured, even if Scr is in normal range at preoperative observation.

Aged↗

PubMed2005

Mu and delta, but not kappa, opioid agonists induce spastic paraparesis after a short period of spinal cord ischaemia in rats.

BACKGROUND: Intrathecal (IT) morphine given after a short interval of aortic occlusion in a rodent model induced transient spastic paraparesis via opioid receptor-predicted actions in spinal cord. To determine the role(s) of spinal opioid receptor subtypes we investigated whether IT administration of various selective opioid receptor agonists can induce paraparesis following a short period of spinal cord ischaemia in rats. METHODS: In Sprague-Dawley rats implanted with an IT catheter, spinal cord ischaemia was induced for 6 min using an intraaortic balloon. Mu ([D-Ala2, N-Me Phe4, Gly-ol5] enkephalin), kappa (U50488H) or delta ([D-Pen(2,5)] enkephalin) selective agonists were injected intrathecally 30 min after reperfusion. A separate group of animals was used to investigate the dose-response effect on this motor dysfunction. For this purpose, three doses of mu, kappa, or delta agonists were injected intrathecally after ischaemia. After IT injection, recovery of motor function was assessed periodically using the motor deficit index (0=complete recovery; 6=complete paraplegia). RESULTS: IT administration of mu and delta but not kappa agonists produced dose-dependent effects in the induction of spastic paraparesis. In addition, this spasticity induced by IT mu and delta agonists was reversed completely by IT naloxone and naltrindole, respectively. CONCLUSION: These results suggest that the effect of various opioids on motor function after a short period of spinal cord ischaemia depends upon individual opioid receptor subtypes.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗

PubMed2005

An elderly female who survived more than 30 years following a diagnosis of Takayasu's arteritis, complicated by fatal intestinal amyloidosis.

Compared to young patients with Takayasu's arteritis (TA), little information about elderly patients with TA has been reported. Additionally, no reports were found regarding TA cases with complications of intestinal amyloidosis. This is a case report of an elderly female, who developed intestinal amyloidosis, during late-stage TA. After years of outpatient management, she developed sudden severe dyspnea with pulmonary effusion, requiring hospitalization. After this event, betamethasone was replaced by methotrexate (MTX) for the next 34 months, but it seemed ineffective. After 1.5 years, she developed intractable diarrhea, followed by increases in BUN and serum creatinine (Cr), requiring several courses of hemodialysis. Colonoscopy revealed the presence of amyloid in her intestine, although she died of complicated sepsis caused by MRSA infection. This may be the first paper describing intestinal amyloidosis in a TA patient. Additionally, her case is rare in that she lived more than 30 years after the onset and diagnosis of TA.

Aged↗

PubMed2005

Biological behavior of myoepithelial cells in the regeneration of rat atrophied sublingual glands following release from duct ligation.

The present study aimed to clarify how myoepithelial cells behave during regeneration of an atrophied sublingual gland by investigating cell proliferation and ultrastructure. Atrophy of rat sublingual glands was induced by unilateral ligation of the excretory duct near the hilum with metal clips, which were then removed after one week of ligation for regeneration. The sublingual glands 0-14 days after unligation were examined with single immunohistochemistry for actin as a marker of myoepithelial cells, double immunohistochemistry for actin and proliferating cell nuclear antigen (PCNA) as a marker of proliferating cells, and transmission electron microscopy (TEM). The single immunohistochemistry and TEM showed that myoepithelial cells surrounded residual ducts in the atrophied glands and immature and mature acini in the regenerating glands. Although PCNA-positive myoepithelial cells were identified during regeneration, PCNA labeling indices of myoepithelial cells were low at all time points except at day 7. Ultrastructurally, myoepithelial cells showing bizarre shaped structures in the atrophy changed with maturation of differentiating acinar cells and appeared normal in the regenerated glands. There was no differentiation of the remaining duct cells to myoepithelial cells. These observations suggest that proliferation of myoepithelial cells and differentiation to myoepithelial cells do not commonly participate in the regeneration of atrophied sublingual glands and that the bizarre shaped myoepithelial cells in the atrophied sublingual glands recover the original shapes with acinar cell regeneration.

Actins↗

PubMed2005

Irinotecan and etoposide for previously untreated extensive-disease small cell lung cancer: a phase II trial of West Japan Thoracic Oncology Group.

Irinotecan is a topoisomerase I inhibitor that is highly active against small cell lung cancer (SCLC). Etoposide is another drug that is effective for SCLC. Since combination of these two topoisomerase inhibitors revealed a synergistic effect in vitro and showed a safety in phase I study, we conducted a phase II study in patients with previously un-treated extensive disease (ED) SCLC to evaluate the efficacy and toxicity of this combination. Fifty patients with previously untreated ED-SCLC were enrolled. Irinotecan was administered intravenously at 60mg/m(2) on days 1, 8, and 15, while etoposide was given at 80mg/m(2) on days 2-4. Treatment was repeated every 4 weeks for four cycles. The overall response rate was 66.0%, with a complete response rate of 10.0%. The median survival time was 11.5 months and the 1- and 2-year survival rates were 43.2 and 14.4%, respectively. The major toxicity of this regimen was myelosuppression, including grade 3 or 4 neutropenia (62.9%), leukopenia (28.0%), and anemia (14%). The other grade 3 toxicity was diarrhea (2%). This irinotecan and etoposide regimen is active against ED-SCLC with relatively mild toxicity.

Adenocarcinoma↗

PubMed2005

Significant magnetoresistance enhancement due to a cotunneling process in a double tunnel junction with single discontinuous ferromagnetic layer insertion.

We fabricate CoFe/AlOx/CoFe/AlOx/CoFe ferromagnetic double tunnel junctions and observe spin-dependent tunneling phenomena. A middle CoFe layer becomes discontinuous by forming CoFe particles two dimensionally, of which the average diameter is evaluated to be 2.0-4.5 nm from cross-sectional transmission electron microscopy images. Below 50 K, a Coulomb gap is observed in current-voltage curves, and both magnetoresistance ratios and resistances are found to increase significantly with decreasing temperature. This indicates that a cotunneling process is dominant within the gap, which agrees very well with theoretical prediction [Phys. Rev. Lett. 80, 1758 (1998)].

Journal Article↗

PubMed2005

Active participation of apoptosis and mitosis in sublingual gland regeneration of the rat following release from duct ligation.

This study was designed to establish how mitotic cell proliferation and apoptotic cell death participate in the regeneration of atrophied rat sublingual glands. To induce atrophy to the sublingual gland of rats, the excretory duct was ligated unilaterally near the hilum, and after 1 week of ligation (day 0) the duct ligation was released to enable gland regeneration. The regenerating glands were examined with routine histology, immunohistochemistry for proliferating cell nuclear antigen (PCNA) as a marker of proliferating cells, terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) as a marker of apoptotic cells, and transmission electron microscopy. At day 0, a few acini and many ducts remained in the atrophic sublingual glands, and newly formed immature acini were observed at day 3. Thereafter acinar cells progressively matured and increased in number, although the number of ducts decreased. Many PCNA- and some TUNEL-positive cells were seen in acini and ducts during regeneration. The labeling indices for both cell types were statistically significantly different from that of the control at several time points of the regeneration. Apoptotic and mitotic cells were also confirmed to be present in the experimental sublingual glands by electron microscopy. These observations suggest that apoptosis as well as mitosis of duct and acinar cells actively participate in and play important roles in sublingual gland regeneration.

Animals↗

PubMed2005

Severity of oral mucositis correlates with the response of oral cancer to preoperative radiochemotherapy.

Oral mucositis is a dose-limiting toxic effect of radiotherapy and chemotherapy on oral cancer. The purpose of the present study is to assess the relationship between tumor response and oral mucositis in preoperative radiochemotherapy for oral cancer retrospectively. Fifty-four cases of oral squamous cell carcinoma were treated with concurrent radiochemotherapy prior to surgery. When oral mucositis was evaluated with the WHO scale, severe oral mucositis (Grades 3 and 4) developed in 22 cases (41%). A more than 50% reduction in tumor size was clinically observed in 38 cases (70%). From histopathological analysis of the surgical specimens all tumor cells observed appeared to be non-viable in 16 cases (29%). The cases with Grade 1, Grade 2, Grade 3 and Grade 4 oral mucositis included 33%, 62%, 85% and 89% of clinical good-response cases and 0%, 24%, 31% and 55% of histopathological good-response cases, respectively. This retrospective study suggests that severe oral mucositis promises a good response of oral squamous cell carcinoma to radiochemotherapy.

Aged↗

PubMed2005

Effects of repeated maternal stress on FOS expression in the hypothalamic paraventricular nucleus of fetal rats.

The effects of repeated prenatal stress with different severity (restraint and immobilization) on Fos expression in the maternal and fetal hypothalamic paraventricular nucleus (PVN) were examined in rats. Acute stress treatment was performed for 30 min on gestational day 21, and repeated stress treatment for 30 min daily for 5 days from gestational days 17-21. In the parvocellular region of the maternal PVN, the stress-induced increases in the number of Fos-immunoreactive neurons were smaller in the repeated stress groups than the acute stress groups, indicating an adaptation of Fos expression to repeated stress. The attenuated Fos expression observed in the maternal PVN following repeated mild stress did not occur in the fetal PVN. In contrast, repeated immobilization stress caused a much smaller increase in Fos expression in the fetal PVN than did acute immobilization stress. The reduced Fos expression in the fetal PVN following repeated severe stress was thought to be due to cell death, since the fetal PVN in the chronic immobilization group revealed a reduction in the total number of cells and an increase in the number of apoptotic cells. In the female but not male fetuses, repeated restraint stress induced a significant increase in the number of apoptotic cells in the PVN. These findings suggest that the fetal PVN shows no adaptation of Fos expression to repeated maternal stress, but great vulnerability to cell death, including apoptosis. In addition, stress-induced apoptosis may more easily occur in the fetal PVN in females than males.

Acute Disease↗

PubMed2005

Update results of FEC followed by docetaxel neoadjuvant trials for primary breast cancer.

This study has been initiated to evaluate the safety, clinical and pathologic response as well as the relation of response (pCR or non-pCR) and survival (overall and relapse-free) of fluorouracil, epirubicin and cyclophosphamide (FEC) followed by docetaxel (DOC) as preoperative chemotherapy in patients with operable breast cancer. Japanese patients with primary breast cancer, Tlc-3N0M0 or T1-3NIM0, age 20-60, PS 0-1 were included in this study. Preoperative chemotherapy consisted of 4 cycles of FEC (500 mg/m(2), 100 mg/m(2), 500 mg/m(2)) every 3 weeks followed by 4 cycles of DOC (75 mg/m(2)) every 3 weeks. Since June 2002, 200 patients were enrolled in this study, and the time of this interim analysis, 80 patients were evaluable for safety and clinical efficacy. The overall clinical response rate was 71.4% (14% CR, 44% PR, 42% SD/PD), and the only G3,4 toxicities, neutropenia and febrile neutropenia were observed in 54% and 14% of patients, respectively. Eighty nine patients were evaluable for pathologic response by central review. Pathologic response was evaluated among invasive tumors on multiple cross-section specimens based on a modified version of the Japanese grading system for Japanese Breast Cancer Society. The pathologic response rate was 17%. In this ongoing trial, FEC followed by DOC was active and well tolerated.

Antineoplastic Agents, Phytogenic↗

PubMed2005

Nutritional status of children in rural Lao PDR: who are the most vulnerable?

A cross-sectional study was undertaken to assess the nutritional status of children aged 3-15 y in remote villages of Lao PDR. Study sites were chosen from two provinces: Luang namtha (north) and Sekong province (south). All the sampled 1075 children were measured for anthropometry, following the standard methods. Dietary intake, morbidity and socio-economic data were obtained by interviews with parents. This study confirmed the high prevalence of growth retardation among children, as well as persistent food insecurity in the remote areas of Lao PDR. Prevalence of stunting was 74.1% in Luang namtha and 62.6% in Sekong province, with school-aged children being worse-off than under-five ones. Children's diets were inadequate in quality as well as in quantity, with very limited availability of rice and other food items throughout the year. Our findings also suggest the negative outcomes of government's development programme were often overlooked, and that more attention should be paid on the fragile living conditions in the resettlement villages, especially for the ethnic minority.

Adolescent↗

PubMed2005

FOXP3, a selective marker for a subset of adult T-cell leukaemia/lymphoma.

FOXP3 is a forkhead transcription factor family member, implicated in T-cell regulation, activation and differentiation. FOXP3 has been shown to be a master control gene for the development and function of CD4+/CD25+ regulatory T-cells (T(reg)). In this study, FOXP3 protein expression has been analysed using a new anti-FOXP3 monoclonal antibody in 172 paraffin-embedded lymphoma samples. FOXP3 expression in tumour cells was confined to adult T-cell leukaemia/lymphoma (ATLL) cases (17/25, 68%), with some variability in the intensity of the staining and the proportion of positive cells. No other lymphoma types studied exhibited FOXP3 expression in the malignant population. The selective expression of FOXP3 by tumour cells in ATLL makes this antibody a potentially useful diagnostic tool.

Antibodies, Monoclonal↗

PubMed2005

Ileocolonic lymphomas: a series of 16 cases.

BACKGROUND: Colonoscopic and clinical differences between primary ileocolonic mucosa-associated lymphoid tissue (MALT) lymphoma and mantle cell lymphoma (MCL) have not been defined. METHODS: We reviewed colonoscopic and clinical features in eight patients with primary MALT lymphoma and eight patients with MCL in the terminal ileum and/or colorectum. All cases were examined for CD5 and/or cyclin D1 expression. RESULTS: Endoscopic features of MALT lymphoma were characterized as protrusions that were covered with normal-appearing mucosa with or without ulceration. The gross appearances of MALT lymphomas were categorized as solitary (4 patients), multiple (3 patients), and multiple lymphomatous polyposis (MLP) (1 patient). The gross features of MCL at endoscopy were categorized as multiple protrusions (2 patients), and MLP (6 patients). The clinical stages of patients with MCL were more advanced than in patients with MALT lymphoma. CONCLUSIONS: Solitary or multiple protrusions at an early clinical stage is the most common presentation pattern of patients with MALT lymphoma, but an MLP appearance at an early stage is also possible. On the other hand, MLP appearance with an advanced clinical stage is the main presentation pattern in patients with MCL, although multiple protrusions with an early clinical stage is also possible. Histological and immunohistochemical investigation including that of cyclin D1 and CD5 expression is essential to make the final diagnosis.

Adult↗

PubMed2005

Comparison of capsule endoscopy and enteroscopy with the double-balloon method in patients with obscure bleeding and polyposis.

BACKGROUND AND STUDY AIMS: Video capsule endoscopy and double-balloon enteroscopy (DBE) are novel methods of enteroscopy. The aim of this investigation was to compare the value of CE and DBE in the diagnosis of small-intestinal pathology. PATIENTS AND METHODS: Thirteen patients with gastrointestinal bleeding of obscure origin and nine patients with known gastrointestinal polyposis were examined using antegrade or retrograde DBE, and the most distal or proximal site in the explored small intestine was marked by submucosal injection of sterilized ink. The patients were then evaluated by CE. Video images obtained by CE were reviewed by an observer who was blinded to the DBE findings. RESULTS: DBE identified positive findings in 12 patients (54.5 %). CE identified positive findings in the area explored by DBE in eight patients (36.4 %), and in the unexplored area in 11 patients (50.0 %). The overall diagnostic yield in the area explored by DBE did not differ between the two procedures. The enteroscopic findings in the area explored by DBE were concordant in 12 of 13 patients with gastrointestinal bleeding of obscure origin. In patients with polyposis, the diagnoses were discordant in three patients, in whom CE failed to detect any polyp. In two of three polyposis patients with concordant positive findings, DBE detected a larger number of polyps than CE did. CONCLUSIONS: DBE appears to be superior to CE in the diagnosis of small-intestinal polyps, whereas the value for diagnosing gastrointestinal bleeding of obscure origin is similar in the two procedures.

Adult↗