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S Nakamura

Publications and source records attributed to S Nakamura.

At least 163 records · Page 9Linked to original sources
PubMed2001

Diagnostic significance of tau protein in cerebrospinal fluid from patients with corticobasal degeneration or progressive supranuclear palsy.

Distinguishing corticobasal degeneration (CBD) from progressive supranuclear palsy (PSP) is clinically and pathologically difficult, and a useful biological marker to discriminative these two diseases has been a subject of clinical interest. In the present study, we assessed tau protein levels in cerebrospinal fluids by sandwich ELISA to distinguish CBD from PSP. The subjects consisted of 27 cases of CBD, 30 cases of PSP, and 36 healthy controls (CTL). The tau values in CBD were significantly higher than those in PSP (P<0.001) and those in CTL (P<0.001). The assay of CSF tau provided diagnostic sensitivity of 81.5% and specificity of 80.0% between CBD and PSP according to receiver-operating characteristic (ROC) curve analysis. When values were compared separately with respect to stage of the disease, differences in the values for moderate CBD vs. moderate PSP had the greatest significance (P<0.001 sensitivity 92.3%, specificity 100.0%), followed by cases of mild CBD and PSP (P<0.005, sensitivity 100.0%, specificity 87.5%). The values in severe CBD and PSP were not significantly different (P=0.07, sensitivity 100%, specificity 75.0%). Using data obtained from a larger number of disease cases, we confirmed our previous findings that tau protein levels in cerebrospinal fluids in patients with CBD are significantly higher than those in patients with PSP. Because tau protein levels in cerebrospinal fluids are significantly higher in early CBD cases than in early PSP cases, measurement of tau protein levels in cerberospinal fluids may be useful for the differential diagnosis of early CBD from early PSP.

Aged↗
PubMed2001

High-frequency oscillations in human posterior tibial somatosensory evoked potentials are enhanced in patients with Parkinson's disease and multiple system atrophy.

High-frequency oscillations (HFOs) and the underlying P37 primary somatosensory response evoked by posterior tibial nerve stimulation were recorded in patients with Parkinson's disease (PD) and in those with multiple system atrophy (MSA), as well as in normal controls. In order to increase the signal-to-noise ratio, we averaged a large number of responses (9998 epochs) with a high sampling rate (20 kHz per channel). HFOs were extracted by filtering the wide band-pass recording of the P37 potential with a 600-900 Hz band-pass filter. High-amplitude HFOs were observed in both the PD and MSA patients. Furthermore, the duration of illness was positively correlated with the amplitude of HFOs. The results suggest that HFOs are enhanced by dysfunction of the basal ganglia.

Aged↗
PubMed2001

Inclusion body myositis: expression of extracellular signal-regulated kinase and its substrate.

OBJECTIVE: To assess abnormal intracellular signal transduction in inclusion body myositis (IBM). BACKGROUND: Mitogen-activated protein kinases (MAPKs) play pivotal roles in intracellular signal transduction and regulate cell growth and differentiation. Upon their activation, MAPKs translocate from the cytoplasm into the nucleus. DESIGN/METHODS: The authors investigated the localization of several forms of the MAPK family-extracellular signal-regulated kinase (ERK), c-Jun N-terminal protein kinase (JNK), and p38 MAPK (p38)-in 10 patients with sporadic IBM and in 52 control subjects. The relationship between the localization of immunopositive deposits and nuclei was tested with bis-benzimide. RESULTS: Vacuolated fibers in IBM displayed very strong focal immunoreactivity of ERK, but not of JNK or p38. The ERK-positive deposits in these vacuolated fibers colocalized with the nuclear substrate of ERK, Elk-1. ERK- and Elk-1-positive deposits were located frequently on the surface of the nuclei in vacuolated fibers in IBM. Similar findings to those of sporadic IBM were observed in three patients with distal myopathy with rimmed vacuoles, but not in eight normal or the other 41 disease controls. CONCLUSION: There is evidence for impaired molecular transport to the nucleus from the cytoplasm in the vacuolated fibers in IBM. This could be due to cytoplasmic aggregation of ERK and Elk-1 or to abnormal nuclear pore machinery involved in the transport of ERK and its substrate upon ERK activation.

Adult↗
PubMed2001

Aldosterone production is activated in failing ventricle in humans.

BACKGROUND: Recent reports have indicated that aldosterone is produced in extra-adrenal tissues in animals. The present study was designed to examine whether aldosterone is produced in human heart. METHODS AND RESULTS: Plasma levels of aldosterone, BNP, and angiotensin-converting enzyme were measured in anterior interventricular vein (AIV), coronary sinus (CS), and aortic root (Ao), respectively, in 20 patients with left ventricular systolic dysfunction (LVSD), 25 patients with LV diastolic dysfunction (LVDD), and 23 control subjects. Aldosterone levels were significantly higher in AIV and CS than Ao in LVSD (98+/-10 versus 72+/-9 pg/mL, P:<0.001, and 97+/-11 versus 72+/-9 pg/mL, P:<0.001, respectively) and LVDD (87+/-10 versus 71+/-9 pg/mL, P:<0.01, and 84+/-10 versus 71+/-9 pg/mL, P:<0.01, respectively) groups, but no differences were observed in levels for these sites in the control group. Levels of ACE activity and BNP also were higher in AIV than Ao in both LV dysfunction groups. The difference in aldosterone levels between AIV and Ao and those in BNP and angiotensin-converting enzyme had a significant positive correlation with LVEDP and a significant negative correlation with LV ejection fraction in the LVSD group. CONCLUSIONS: Production of aldosterone, angiotensin-converting enzyme, and BNP are activated in failing human ventricle in proportion to severity.

Adult↗
PubMed2001

Infrequent microsatellite instability in biliary tract cancer.

BACKGROUND AND OBJECTIVES: Microsatellite instability (MSI) has been reported in several tumors. However, few reports are available concerning MSI in biliary tract cancers. We investigated MSI and allelic loss at the hMLH1 and hMSH2 gene loci in biliary tract cancers. METHODS: We analyzed microsatellite alterations using 7 microsatellite markers in 38 cases of extrahepatic bile duct (EHBD) cancer and 16 cases of ampullary cancer using polymerase chain reaction and an automated fluorescent DNA sequencer. RESULTS: A MSI prevalence of 13.2% (5/38) was observed for EHBD cancer and a prevalence of 12.5% (2/16) was observed for ampullary cancer. Loss of heterozygosity at the hMLH1 and hMSH2 gene loci were observed in 4% (1/25 informative cases) and 6.1% (2/33) of EHBD cancer cases, respectively; and in 11.1% (1/9) and 8.3% (1/12) of ampullary cancer cases, respectively. The cumulative survival rate of patients with MSI was significantly better than that of patients without MSI in EHBD cancer. However, MSI was not an independent prognostic factor. CONCLUSIONS: Our results suggest that genetic defects in the DNA mismatch repair system and MSI do not play an important role in the majority of biliary tract cancers.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Mutation of the doublecortin gene in male patients with double cortex syndrome: somatic mosaicism detected by hair root analysis.

The molecular basis of double cortex syndrome was investigated in 2 male patients. Magnetic resonance imaging of the patients' heads showed diffuse subcortical band heterotopia, as is seen in female patients. We found a heterozygous mutation for Asp50Lys or Arg39Stop in both patients. Microsatellite polymorphism analysis revealed that both patients had inherited a single X chromosome from their mothers. Restriction enzyme analysis using DNA extracted from the hair roots of each patient showed four different patterns in the combination of cells carrying wild and mutant alleles, which strongly suggest somatic mosaicism. We conclude that somatic mosaic mutations in the doublecortin gene in male patients can cause subcortical band heterotopia, and that molecular analysis using hair roots is a useful method for detecting somatic mosaicism.

Cerebral Cortex↗
PubMed2001

Correlates of bundle-branch block in patients undergoing primary angioplasty for acute myocardial infarction.

BACKGROUND: Early reperfusion therapy has reduced the infarct size and mortality rate in patients with acute myocardial infarction (AMI). The occurrence of bundle-branch block in AMI is related to the amount of myocardial damage and the insult to the conduction system. HYPOTHESIS: To evaluate the clinical and angiographic factors related to the occurrence of bundle-branch block (BBB) in patients with primary percutaneous transluminal coronary angioplasty (PTCA), we investigated consecutive series of patients with their first Q-wave AMI and successful PTCA. METHODS: Coronary angiogram at the time of admission, electrocardiogram, and echocardiogram were evaluated in 279 patients with their first Q-wave AMI and successful PTCA. RESULTS: Bundle-branch block was detected in 26 patients (9%); 16 patients had transient and 10 patients had persistent block, while 16 patients had bifascicular block and 10 patients had right BBB. The patients with BBB had a significantly larger number of left ventricular asynergic segments, higher incidence of total occlusion of infarct-related artery, angiographic no reflow, and pericardial rub than those without BBB. When the multivariate analysis was performed using five clinical markers of infarct severity, angiographic no reflow (F = 20.2, p < 0.001) and total occlusion of infarct-re-lated artery (F = 4.2, p = 0.04) were found to be the significant variables related to BBB. CONCLUSIONS: Despite successful primary PTCA, absence of antegrade flow in the infarct-related artery at the onset of AMI and/or angiographic no reflow resulted in more severe transmural myocardial damage and, hence, the occurrence of BBB.

Aged↗
PubMed2001

Characteristics of mutations generated through digestion with restriction enzyme and ligation in plasmid DNA.

Recently, the use of restriction enzymes has been extended to studies in which rare events such as mutation and mistakes in DNA repair are examined. In these studies, the specificity of restriction enzymes becomes critical. To clarify the nature of the rare unexpected events occurring in the process of cutting of DNA with restriction enzymes then ligating it, we studied the molecular characteristics of unexpected plasmid DNAs that were retrieved as mutants of the plasmid after transfection to E. coli. The plasmid used was pUR288, containing lacZ as a marker of mutation. It was digested with restriction enzymes under the conditions recommended by the supplier of the enzymes and under the presence of DMSO, which is known to induce star activity of the enzymes. Comparisons of mutant frequencies and of nucleotide sequences of the mutants found in the different conditions indicated that nonspecific endonucleolytic activity similar to that found under star activity was present under the recommended conditions and, further, was responsible for the creation of deletion-type mutations. The frequency of these events ranged from 10(-5) to 10(-3), depending on the kind of restriction enzymes analyzed. Although the levels of the nonspecificity were not high, they should be considered in assays such as mutation and mistakes in DNA repair, where rare events are examined.

Base Sequence↗
PubMed2001

A comparison of ovarian metastasis between squamous cell carcinoma and adenocarcinoma of the uterine cervix.

OBJECTIVE: The purpose of our study was to investigate a possible difference in ovarian metastasis between squamous cell carcinoma and adenocarcinoma of the uterine cervix and to confirm clinicopathological variables associated with the metastases. METHODS: Clinical and pathological variables of 1064 patients with invasive squamous cell carcinoma and 240 with adenocarcinoma were studied. RESULTS: Ovarian metastasis was found in 14 patients (1.3%) with squamous cell carcinoma and 15 (6.3%) with adenocarcinoma. The mean age of patients with ovarian metastasis of squamous cell carcinoma was 57.4 years, compared to 50.2 years for adenocarcinoma. Ovarian metastasis of adenocarcinoma was more likely to be visible (40.0%) and present in both ovaries (66.7%), while these two characteristics occurred in only 21.4 and 36.7% of patients with squamous cell carcinoma. A logistic regression analysis with clinical variables indicated that clinical stage beyond IIb was a significant variable of squamous cell carcinoma, and more than 30-mm tumor size was significant in adenocarcinoma. CONCLUSION: The incidence of ovarian metastasis of adenocarcinoma of the uterine cervix was significantly higher than that of squamous cell carcinoma. The incidence of adenocarcinoma was associated more closely with tumor size than clinical stage, whereas it was more associated with clinical stage in squamous cell carcinoma. The results thus suggested that the differences in ovarian metastases were caused by the different characteristics of the two types of carcinoma.

Adenocarcinoma↗
PubMed2001

Assessment of cardiovascular autonomic dysfunction in multiple system atrophy.

Because heart rate is controlled mainly by the autonomic nervous system, cardiovascular autonomic dysfunction may contribute to the prognosis of patients with multiple system atrophy (MSA). To clarify cardiovascular autonomic dysfunctions in MSA, the authors investigated the relation between blood pressure (BP) and pulse rate (PR), and assessed a power spectral analysis of heart rate variability (HRV) during the clinical course using ambulatory BP and a heart rate monitor for 24 hours. The authors studied seven patients with MSA (five men and two women, aged 61.0 +/- 5.8 years) and seven healthy volunteers (four men and three women, aged 58.0 +/- 6.6 years) without hypertension, heart disease, or intracranial lesions. The MSA group showed abnormal circadian variations of BP and PR and a significantly decreased correlation coefficient between BP and PR. A significant decrease and altered circadian variation also existed in the number of changes in successive R-R intervals greater than 50 msec (RR50) and in the power of the high- and low-frequency component of HRV. The authors observed a significant negative correlation between the duration of illness and the number of changes in successive R-R intervals greater than 50 msec. The characteristic dysautonomia in MSA was a decrease in sympathetic and parasympathetic activity, with an abnormal circadian rhythm of BP and HRV. The balance between sympathetic and parasympathetic activity was also impaired. The parasympathetic modulation represented by RR50 worsened according to the development of the illness. Those autonomic dysfunctions may have affected the cardiovascular systems, which may indicate a poor prognosis in patients with MSA. An analysis of HRV and the circadian rhythm of BP and HRV are useful in evaluating cardiac autonomic dysfunctions in MSA.

Aged↗
PubMed2001

3D-MR mammography-guided breast conserving surgery after neoadjuvant chemotherapy: clinical results and future perspectives with reference to FDG-PET.

BACKGROUND: Three dimensional MR Mammography (3D-MRM) can detect tumor extension more accurately than mammography or ultrasound. There are two shrinkage patterns observed by 3D-MRM after neoadjuvant chemotherapy. Concentric shrinkage is a good indication for breast conserving surgery. On the other hand, a dendritic pattern was represent ductal spread. Therefore, we developed MRM guided mapping to aid BCS for tumors showing a dendritic pattern. METHODS: Fifteen patients consisting of 8 stage II (T > 3.5 cm) cases and 7 stage IIIa cases aged 39 to 61 years (mean 47-8 years) were treated with AT neoadjuvant chemotherapy with the aim of performing breast conserving surgery. All patients were examined by 3D-MRM before and after neoadjuvant chemotherapy. Breast conserving surgery indications were determined by tumor volume reduction and shrinkage patterns on 3D-MRM. Supine position mapping using MRM was performed for dendritic type tumors. FDG-PET was simultaneously performed for one case with bilateral breast cancer. RESULTS: Breast conserving surgery was performed for 13 of the 15 cases. One case underwent re-operating and mastectomy because of a positive margin. One case had microscopically positive margin and received boost radiation. Therefore, 11 of 15 cases (73.3%) underwent BCS and achieved negative margins under MRM guidance. PET scanning can detect residual tumor and occult metastasis but it is not suitable for mapping because of its spatial resolution. CONCLUSIONS: 3D-MRM is a useful modality to select appropriate cases for breast conserving surgery after neoadjuvant chemotherapy. FDG-PET can also detect residual tumor or occult metastasis but it may not be suitable for mapping. Because both examinations have potential, further evaluation of their clinical efficacy is necessary.

Adult↗
PubMed2001

Peripheral T/natural killer-cell lymphoma involving the female genital tract: a clinicopathologic study of 5 cases.

Malignant lymphoma of the female genital tract (FGT) is rare. In this study, 5 peripheral T/natural killer (NK)-cell lymphomas (PTCLs) involving the FGT are reported. They include 2 from the uterus and 1 each from ovary, uterus and ovary, and vagina, and were detected between 1996 and 2000. One of the 2 ovarian tumors was bilateral. In all cases, the FGT was the initial site of clinical presentation of disease. Age at presentation ranged from 21 to 52 years (median, 36 years). One case was stage I disease, 2 were stage II, and 2 were stage IV. All 5 tumors were positive for CD3epsilon, and 3 harbored the Epstein-Barr virus, although the detailed immunophenotypic profiles varied. Three were diagnosed as nasal type T/NK-cell lymphoma, 1 as anaplastic large-cell lymphoma (anaplastic lymphoma kinase [ALK]-positive), and 1 as unspecified PTCL of cytotoxic phenotype, according to the forthcoming World Health Organization classification. Four of 5 patients received laparotomy and chemotherapy. Four patients (in stages II and IV) died of disease within 16 months of the initial diagnosis, whereas only 1 patient (in stage I) is alive without disease at 39 months of follow-up. Our experience in this series provided clinically relevant information on diagnosis, treatment, and outcome for extremely rare tumors of the FGT.

Adult↗
PubMed2001

Assessment of prognostic factors in follicular lymphoma patients.

Prognostic factors, including clinical, biological, and histological parameters, were assessed for 94 patients with follicular lymphomas at our institute. Follicular lymphomas constituted 7.7% (94/1208) of malignant lymphomas in this study. Eighteen patients were diagnosed with stage I follicular lymphoma, 20 with stage II, 23 with stage III, and 33 with stage IV. The cases of follicular lymphoma were subclassified as: follicular small cleaved cell lymphoma (FSC) in 20 cases, follicular mixed cell lymphoma (FMX) in 59 cases, and follicular large cell lymphoma (FLC) in 15 cases. The patients comprised 49 men and 45 women with a median age of 54 years (range, 25-84 years). The complete response rate was 76.5%, and the median survival time was 13 years. The expected 10-year overall survival and event-free survival rates were 61.9% and 38.2%, respectively. Univariate analysis identified the factors associated with poor survival as elevated serum lactate dehydrogenase (LDH) level (P < .0001), age of >60 (P < .0001), Ann Arbor stage III/IV (P < .01), and Eastern Cooperative Oncology Group performance status (PS) of 2 to 4 (P = .048). Multivariate analysis showed that LDH, age, and PS were independent predictors. After application of the International Prognostic Index (IPI), the 10-year survival rates for the low-risk, low-intermediate risk, high-intermediate risk and high-risk groups were 80.4%, 48.7%, 21.9%, and 0.0%, respectively. The differences among these groups were significant at P < .01. The IPI for aggressive non-Hodgkin's lymphoma was found to be applicable to survival prediction for Japanese follicular lymphoma patients.

Adult↗
PubMed2001

Pregnancy-associated cytotoxic lymphoma: a report of 4 cases.

The clinicopathological and biological significance of Hodgkin's disease and non-Hodgkin's lymphoma, which are infrequently encountered in women of childbearing age, remains to be clarified. We recently reviewed 4 cases of non-Hodgkin's lymphoma of the T/natural killer (T/NK)-cell phenotype, all of which were associated with pregnancy and characterized by the expression of the cytotoxic granule-associated proteins T-cell intracellular antigen-1 and/or granzyme B. The 4 cases selected had presented between November 1993 and May 1999. The criteria for selection were that the onset of clinical manifestations occurred during pregnancy or within 6 months after delivery. The patients comprised 1 patient with p80/anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL), 1 with p80/ALK-negative ALCL, and 2 with peripheral T/NK-cell lymphomas of unspecified type. The diseases followed aggressive clinical courses: 3 patients died within 6.5 months after diagnosis, and only 1 was still alive with the disease 17 months after diagnosis. The diseases appeared to progress rapidly after delivery. Maternal immunity and hormonal changes during pregnancy may be closely related to the biological behavior of these unusual tumors. This study is, to the best of our knowledge, the first to address pregnancy-associated cytotoxic lymphoma.

Adult↗
PubMed2001

CD34+-selected autologous peripheral blood stem cell transplantation conditioned with total body irradiation for malignant lymphoma: increased risk of infectious complications.

Although high-dose chemotherapy with autologous peripheral blood stem cell transplantation (autoPBSCT) has been shown or confirmed to be an effective treatment for high-risk and relapsed non-Hodgkin's lymphoma (NHL), relapse after autoPBSCT remains a serious problem. In a clinical trial to overcome relapse, we adopted a treatment plan in which PBSCs purified in vitro to CD34+ cells to deplete tumor cells (CD34+ autoPBSCT), total body irradiation (TBI) of 1200 cGy, and melphalan, 180 mg/m2, were used as a preconditioning regimen. Eighteen patients with relapsed or high-risk NHL participated in the study. This study compared the incidence of complications following CD34+ autoPBSCT preconditioned with the TBI regimen (n = 10): the TBI group; CD34+ autoPBSCT with the non-TBI regimen (n = 8): the non-TBI group; and unselected autoPBSCT with the non-TBI regimen (n = 19): the unselected autoPBSCT control group. After day 30 posttransplantation, 6 of 10 patients treated with the TBI regimen developed 11 infectious complications in total, compared with only 1 of 8 patients treated with the non-TBI regimen and 4 of 19 patients given unselected autoPBSCT. Two fatal complications occurred in the TBI group, but none occurred in the other 2 groups. The CD4+ lymphocyte count at 1 month posttransplantation was significantly lower in the TBI group than in the unselected autoPBSCT group. These findings suggest that the addition of TBI to the preconditioning regimen for CD34+ autoPBSCT is associated with an increased incidence of severe infectious complications after transplantation.

Adult↗
PubMed2001

A clinicopathological study of 20 patients with T/natural killer (NK)-cell lymphoma-associated hemophagocytic syndrome with special reference to nasal and nasal-type NK/T-cell lymphoma.

We describe the clinicopathological features of 20 patients with T/natural killer (NK)-cell lymphoma-associated hemophagocytic syndrome (T/NK-LAHS). These patients were categorized into 2 groups according to the onset of hemophagocytic syndrome (HPS). Group 1 developed HPS during the clinical course, typically at the terminal phase of the disease. This group consisted of 7 patients with extranodal lymphoma arising in the nasal cavity, paranasal cavity, tonsils, or skin at presentation. In 5 of these patients, the preferred diagnosis was nasal and nasal-type NK/T-cell lymphoma, whereas the disease diagnoses in the remaining 2 patients were peripheral T-cell lymphoma of unspecified type and angioimmunoblastic T-cell lymphoma, respectively. Group 2 consisted of 13 patients whose disease corresponded to so-called malignant histiocytosis-like lymphoma, which is characterized by HPS at the initial presentation and the infiltration of the liver, spleen, and/or bone marrow without tumor formation. Nine of these 13 cases were found to have common histopathological features: CD56+, Epstein-Barr virus positivity, cytotoxic molecules, and nasal-type NK/T-cell lymphoma. The very poor prognosis of T/NK-LAHS may be partly explained by the finding that nasal and nasal-type NK/T-cell lymphoma, which is resistant to standard chemotherapy, made up the highest percentage (70%) of the cases.

Adolescent↗
PubMed2001

Malignant fibrous histiocytoma of the vagina.

We describe here the case of an 82-year-old woman presenting with a hemorrhagic tumor on the anterior vaginal wall. She was diagnosed with malignant fibrous histiocytoma (MFH) from the findings of cytological analysis of biopsied surface tissue, histopathologic analysis of biopsied tissue, immunohistochemical staining, and electron microscopy. Cytological analysis of the biopsy sample harvested from the tumor surface showed multinucleated giant cells and large atypical cells with rough, granular, chromatin, as well as notable nucleoli. A storiform pattern was observed histopathologically, and immunohistochemical staining confirmed positive reactions to alpha 1-antichymotripsin (alpha 1-ACT), vimentin, and lysosome, but negative reactions to epithelial membrane antigen (EMA), cytokeratin, and alpha-smooth muscle action (alpha-SMA). Electron microscopy showed histiocyte-derived cells with a segmented nucleus with a large groove, pseudopodic cytoplasmic projections, and lysosome-like structures. However, intercellular adhesion factors were not notable, and microvilli were absent. Based on the above findings, a diagnosis of MFH originating from the vaginal wall was made. Because of the patient's advanced age, and, in accordance with her wishes, three courses of cancer chemotherapy, consisting of doxorubicin hydrochloride, fluorouracil, and cisplatin were carried out, without surgery. No reduction in the size of the tumor was seen at follow up, and despite the absence of metastasis and no exacerbation of her general condition, she died suddenly at home 2 years after being discharged.

Aged↗