Search PubMed⌕ Search

Biomedical subjects

K Tsuchiya

Publications and source records attributed to K Tsuchiya.

At least 37 records · Page 2Linked to original sources
PubMed2003

Detection of antibody for the serodiagnosis of hantavirus infection in different rodent species.

Peroxidase-labeled staphylococcal protein A, streptococcal protein G, and antibodies directed against Mus musculus (mouse), Rattus norvegicus (rat), Mesocretus auratus (hamster), and Peromyscus leucopus were examined for their reactivity with immunoglobulin G (IgG) from various rodent species. The purpose of this study was to identify the optimal secondary antibodies or reagents for specific serodiagnosis of hantavirus infection in various rodent species. Using ELISA, a total of 65 sera from 29 rodent species of the family Muridae and one serum sample from family Octodontidae were compared for IgG reactivity with the six different reagents. The results demonstrate that the reactivities of the secondary antibodies and reagents to the sera varied, even among sera from rodents of the same genus. Hantavirus-specific antibody ELISA revealed that hantavirus-infected rodent sera obtained from M. musculus, R. norvegicus, Apodemus agrarius, A. peninsulae, and Bandicota indica bound to the six different conjugates in a similar pattern as that detected in IgG ELISA. These results indicate that the applicability of secondary antibodies and protein A and G should be carefully evaluated before use for serodiagnosis in different rodent species.

Animals↗
PubMed2003

Rice stripe virus 23.9 K protein aggregates and forms inclusion bodies in cultured insect cells and virus-infected plant cells.

The genome of Rice stripe virus (RSV, genus Tenuivirus) contains seven open reading frames (ORFs). Little is known about the products of four of these ORFs, including the 23.9 K protein encoded by the virus-sense ORF of RNA3. Western blotting revealed that the 23.9 K protein was synthesized in the host plant and also in the planthopper vector of RSV. Using a baculovirus vector, the 23.9 K protein was expressed, both unfused and fused with red-shifted green fluorescent protein, in Spodoptera frugiperda cells. Inclusion bodies were observed by light microscope in cells expressing fused or unfused proteins. Inclusion bodies in cells expressing the fused protein fluoresced under blue light. By immunoelectron microscopy, electron-dense inclusion bodies in cells expressing the unfused protein were specifically labeled with 23.9 K protein antiserum. Moreover, electron-dense masses labeled with 23.9 K protein antiserum were observed in virus-infected wheat tissue by electron microscopy. This paper thus demonstrates that RSV 23.9 K protein can aggregate in vivo and form inclusion bodies in infected plant tissue.

Animals↗
PubMed2003

Subcutaneous nodules on the buttocks as a manifestation of dialysis-related amyloidosis: a clinicopathological entity?

While beta 2-microglobulin amyloidosis occurring in patients undergoing long-term dialysis is frequently associated with joint involvement, skin lesions have rarely been encountered. We report a 57-year-old man with extensive subcutaneous amyloid deposition forming large nodules on the buttocks; the patient had been on maintenance dialysis for 28 years. Although this condition is rare, a review of the literature indicates that the majority of such lesions occur around the buttock region.

Amyloidosis↗
PubMed2003

Endoscopic mucosal resection of superficially spreading colonic neoplasms larger than 5 cm in the right colon after injection of dilute sodium hyaluronate: report of two cases.

Submucosal injection is the most important procedure for the safe performance of endoscopic mucosal resection in the large intestine while avoiding the risk of perforation. We used dilute sodium hyaluronate containing Bosmin and achieved safe piecemeal resection of large superficial tumors in the right colon in two patients. Piecemeal snare resection is considered to be acceptable if all the tissue pieces can be collected for histopathological diagnosis.

Colonic Neoplasms↗
PubMed2003

Volume-rendered 3D display of MR angiograms in the diagnosis of cerebral arteriovenous malformations.

PURPOSE: To determine whether application of a volume-rendered display of 3D time-of-flight (TOF) MR angiography could assist the diagnosis of cerebral arteriovenous malformations (AVMs). MATERIAL AND METHODS: Volume-rendered 3D images of postcontrast 3D time-of-flight MR angiography were compared with conventional angiograms in 12 patients. The correlation between the 3D images and the operative findings was also analyzed in 5 patients. RESULTS: The 3D-displayed images showed all of the feeders and drainers in 10 and 9 patients, respectively. In all patients, the nidus was three-dimensionally visualized. In 3 patients with hematomas, the relationship between the hematoma and the AVM was well demonstrated. The 3D images corresponded well with the operative findings in the 5 patients. CONCLUSION: This method is of help in assessing the relationship between the components of an AVM as well as that between an AVM and an associated hematoma.

Adolescent↗
PubMed2003

Content of reticulocyte hemoglobin is a reliable tool for determining iron deficiency in dialysis patients.

BACKGROUND: The evaluation of iron status in dialysis patients provides information essential to the planning of adequate recombinant human erythropoietin (rHuEPO) treatment. Iron status of the patients can be determined from the recently available measurement of content of reticulocyte hemoglobin (CHr). METHODS: In this study, to clarify the accuracy of CHr in diagnosing iron deficiency in hemodialysis (HD) patients, we initially compared CHr with such conventional iron parameters as serum ferritin levels, transferrin saturation and serum soluble transferrin receptor levels. Secondly, we investigated the changes in CHr during iron supplementation for iron-deficient patients to determine whether this marker is a prospective and reliable indicator of iron sufficiency. The participants in this study were 149 hemodialysis (HD) patients and 53 age-matched healthy subjects. Iron deficiency was defined as having a TSAT of less than 20% and serum ferritin of less than 100 ng/ml. Conventional parameters of red blood cells and CHr were measured by an ADVIA120 autoanalyzer. RESULTS: Mean CHr was 32.3 +/- 2.2 pg in the patients undergoing hemodialysis treatment. CHr significantly correlated with iron parameters in the dialysis patients. Logistic regression analysis was performed to determine the relationship between CHr and each outcome measure, and CHr was the significant multivariate predictor of iron deficiency. Iron supplements given to the patients with low CHr and hematocrit (Hct) significantly increased Hct, resulting in a decrease in the weekly dosage of rHuEPO. CONCLUSIONS: CHr, measured simultaneously with Hct, is a sensitive and specific marker of iron status in dialysis patients.

Adult↗
PubMed2003

[Surgery for distal aortic arch aneurysm with a patent left internal mammary-to-coronary artery graft; report of a case].

We report a case of 62-year-old male who suffered from a distal aortic arch aneurysm developed 5 years after coronary artery bypass grafting (CABG). Preoperative angiography revealed a distal arch aneurysm and a patent left internal mammary artery (LIMA) graft. Graft replacement of the total aortic arch was performed using a 4 branched graft. After the re-median sternotomy, cardiopulmonary bypass was established with ascending aortic perfusion and right atrium (RA) drainage. Myocardial protection was achieved with root cold blood cardioplegia and LIMA continuous cold blood perfusion. Distal anastomosis was performed under selective cerebral perfusion and during deep hypothermic circulatory arrest. Postoperative course was satisfactory and the patient was discharged without complications.

Aorta, Thoracic↗
PubMed2002

Constant involvement of the Betz cells and pyramidal tract in amyotrophic lateral sclerosis with dementia: a clinicopathological study of eight autopsy cases.

We investigated clinicopathologically pyramidal signs, including hyperreflexia, Babinski sign, and spasticity, and the involvement of the primary motor cortex and pyramidal tract, in eight Japanese autopsy cases of amyotrophic lateral sclerosis (ALS) with dementia. Pyramidal signs were observed in seven (88%) of the eight autopsy cases. Hyperreflexia and Babinski sign were evident in seven (88%) and three (38%) patients, respectively, but spasticity was not observed in any of the eight patients. Loss of Betz cells in the primary motor cortex was evident in the seven cases in which this structure was examined. Astrocytosis in the fifth layer of the primary motor cortex was noticed in three cases. In all eight cases, involvement of the pyramidal tract was obvious in the medulla oblongata, but no involvement of the pyramidal tract was found in the midbrain. Involvement of the pyramidal tract in the spinal cord, particularly of large myelinated fibers, was observed in all six cases in which the spinal cord was examined. In ALS with dementia, pyramidal signs were shown to be present more frequently than previously believed, and the clinicopathological correlation between pyramidal signs and involvement of the pyramidal tract was obvious. Constant involvement of Betz cells and the pyramidal tract in ALS with dementia has not been reported. Our clinicopathological findings may make a contribution to the understanding of the clinicopathological hallmarks of this disorder. Furthermore, we believe that this study will also contribute to the elucidation of the nosological status of ALS with dementia.

Adult↗
PubMed2002

Diffusion-weighted magnetic resonance imaging of dural sinus thrombosis.

Magnetic resonance imaging (MRI) is useful to diagnose dural sinus thrombosis. However, the representative appearance of dural sinus thrombosis on diffusion-weighted MRI has not been established. This study was aimed at determining whether cytotoxic or vasogenic edema is more predominant in the affected cerebral parenchyma and assessing the time courses and prognosis of dural sinus thrombosis lesion. The studies on sixteen patients with dural sinus thrombosis who underwent diffusion-weighted MRI were retrospectively reviewed. The diagnosis was confirmed by digital subtraction angiography in 11 patients and magnetic resonance angiography in five patients. Diffusion-weighted images with echo-planar imaging were obtained using two or three b values, with the highest b value of up to 1,000 s/mm(2). A region of interest was placed on an area of abnormal signal intensity to calculate apparent diffusion coefficients (ADCs). Nine of the 16 patients had lesions with an increased ADC, whereas, three of these nine patients also had lesions with a decreased ADC. Among 11 patients who underwent initial MRI within 7 days of their last episode, eight had lesions with an increased ADC, of whom three had lesions mixed with both decreased and increased ADC areas. Follow-up studies of these three patients revealed the development of hemorrhagic infarction in two and subcortical hemorrhage in one. Vasogenic edema develops more predominantly and earlier in dural sinus thrombosis, though cytotoxic edema was also associated with the pathological changes in the early phase. Decrease of ADC value is presumed to reflect severe pathological conditions and indicate possible future development of infarction or hemorrhage.

Adult↗
PubMed2002

The acceleration of cosmic-ray protons in the supernova remnant RX J1713.7-3946.

Protons with energies up to approximately 10(15) eV are the main component of cosmic rays, but evidence for the specific locations where they could have been accelerated to these energies has been lacking. Electrons are known to be accelerated to cosmic-ray energies in supernova remnants, and the shock waves associated with such remnants, when they hit the surrounding interstellar medium, could also provide the energy to accelerate protons. The signature of such a process would be the decay of pions (pi(0)), which are generated when the protons collide with atoms and molecules in an interstellar cloud: pion decay results in gamma-rays with a particular spectral-energy distribution. Here we report the observation of cascade showers of optical photons resulting from gamma-rays at energies of approximately 10(12) eV hitting Earth's upper atmosphere, in the direction of the supernova remnant RX J1713.7-3946. The spectrum is a good match to that predicted by pion decay, and cannot be explained by other mechanisms.

Journal Article↗
PubMed2002

Distribution of basal ganglia lesions in diffuse neurofibrillary tangles with calcification: a clinicopathological study of five autopsy cases.

We investigated five Japanese autopsy cases of diffuse neurofibrillary tangles with calcification (DNTC), both clinically and pathologically, and examined the degree and distribution of the basal ganglia lesions, especially in the amygdala, striatum, pallidum, and substantia nigra. The lesions in the amygdala, striatum, and pallidum were classified into three categories (mild, moderate, and severe). The lesions in the substantia nigra were qualitatively judged, compared with normal controls. Severe dementia was observed in four cases neuropathologically showing pronounced neuronal loss in the cerebral cortex, but one case without neuronal loss in the cerebral cortex showed mild memory disturbance. Extrapyramidal signs were evident in three cases. Obvious neuronal loss in the substantia nigra with the presence of Lewy bodies was noticed in four cases. Basal ganglia lesions in all five cases were uniform: the amygdala showed severe to moderate lesions, the caudate nucleus moderate to slight lesions, and the putamen and pallidum slight lesions to normal. Furthermore, the lesions in the amygdala were more prominent in the basolateral group than in the corticomedial group, inconsistent with those in the amygdala of Alzheimer's disease. Moderate lesions were evident in the basolateral group of the amygdala in the case without neuronal loss in the cerebral cortex. In DNTC, the degree and distribution of the basal ganglia lesions, except for nigral lesions, were analogous to those found in Pick's disease with Pick bodies. These clinicopathological findings may contribute to the elucidation of the clinicopathological hallmarks in this disorder.

Age of Onset↗
PubMed2002

Abnormal expression of epidermal growth factor and its receptor in the forebrain and serum of schizophrenic patients.

Epidermal growth factor (EGF) comprises a structurally related family of proteins containing heparin-binding EGF-like growth factor (HB-EGF) and transforming growth factor alpha (TGFalpha) that regulates the development of dopaminergic neurons as well as monoamine metabolism. We assessed the contribution of EGF to schizophrenia by measuring EGF family protein levels in postmortem brains and in fresh serum of schizophrenic patients and control subjects. EGF protein levels were decreased in the prefrontal cortex and striatum of schizophrenic patients, whereas the levels of HB-EGF and TGFalpha were not significantly different in any of the regions examined. Conversely, EGF receptor expression was elevated in the prefrontal cortex. Serum EGF levels were markedly reduced in schizophrenic patients, even in young, drug-free patients. Chronic treatment of animals with the antipsychotic drug haloperidol had no influence on EGF levels in the brain or serum. These findings suggest that there is abnormal EGF production in various central and peripheral tissues of patients with both acute and chronic schizophrenia. EGF might thus provide a molecular substrate for the pathologic manifestation of the illness, although additional studies are required to determine a potential link between impaired EGF signaling and the pathology/etiology of schizophrenia.

Adult↗
PubMed2002

A cytogenetic study of in-vitro matured murine oocytes after ICSI by human sperm.

BACKGROUND: The purpose of this study was to investigate the chromosomal complement and developmental potential of in-vitro matured murine oocytes following ICSI by human sperm. METHODS: Heterologous ICSI fertilization between mouse oocytes and human sperm was employed in order to overcome the reduced fertilization rates observed after conventional IVF due to zona hardening during in-vitro maturation, and to assess separately maternal and paternal chromosome complements. Cytogenetic analyses were performed in four types of oocytes: (i) in-vitro matured metaphase II (MII) oocytes; (ii) in-vivo matured MII oocytes; (iii) in-vitro matured oocytes after ICSI; (iv) in-vivo matured oocytes after ICSI. RESULTS: Activation rates after ICSI of in-vitro matured oocytes was lower than that of in-vivo matured oocytes (69.9 versus 97.2%, P < 0.01), and premature chromosomal condensation was only observed in in-vitro matured oocytes. However, there were no significant differences in developmental rates after successful activation between in-vivo and in-vitro matured ICSI oocytes (69.7 versus 76.6%). The incidences of aneuploidy and structural aberrations were similar between the ICSI embryos and non-ICSI (MII) oocytes. Furthermore, the frequency of chromosomal aberrations was not associated with in-vitro or in-vivo maturation. Similar analyses of paternal chromosomes indicated that there were no significant differences in the incidence of chromosomal aberrations between the embryos derived from in-vitro and in-vivo matured oocytes. CONCLUSIONS: These results suggest that in-vitro matured oocytes following ICSI do not lead to an increase in the frequency of aneuploidy and structural aberrations when human sperm are injected into mouse oocytes.

Aneuploidy↗
PubMed2002

[A study of isolated tricuspid valve surgery late after left heart valve operation].

Management of severe tricuspid regurgitation late after left heart valve operation is controversial. There has been reluctance to the operation due to the high risk of repeat operation, coexistent right ventricular dysfunction and pulmonary hypertension. We investigated 6 cases of isolated tricuspid valve surgery (tricuspid valve replacement: 2, tricuspid valve plasty: 4) late after left heart valve operation. Before operation, these patients showed poor general condition (4 cases were NYHA III or IV) but good left ventricular function [mean ejection fraction (EF) 66 +/- 9.6%]. Hospital mortality was 0% and the mean mid-term actual event-free survival over 2 +/- 1.8 years was 80%. Most of patients demonstrated NYHA I and improvement of hepatomegaly after operation. There were many complications in 2 cases that had been performed previous operation more than 20 years before. In summary, the patient who complained symptoms due to right heart ventricular failure and showed good left ventricular function after left heart valve surgery should be considered to undergo tricuspid valve operation before the occurrence of other complications.

Aged↗
PubMed2002

[Aneurysm of the noncoronary sinus of valsalva associated with aortic regurgitation: report of a case].

A 39-year-old man has complained of palpitation and dyspnea since 8 months ago. With aortic regurgitation pointed out in another hospital, he was referred to our hospital for examination. Preoperative ultracardiography (UCG) showed a dilated noncoronary sinus of Valsalva and aortic regurgitation. A daughter aneurysm was found by aortography. There were 2 perforations and 1 pouch at the noncoronary sinus cusp (NCC). The noncoronary sinus of Valsalva was dilated and the orifice to the daughter aneurysm was noticed. The noncoronary sinus of Valsalva was obliterated by suturing a dacron patch on the orifice. The aortic valve was replaced with ATS 23 mm valve. Postoperative computed tomography (CT) showed clot formation outside the patch.

Adult↗
PubMed2001

Lead content of brain tissue in diffuse neurofibrillary tangles with calcification (DNTC): the possibility of lead neurotoxicity.

Diffuse neurofibrillary tangles with calcification (DNTC) is a form of presenile dementia, characterized pathologically by fronto-temporal atrophy with neurofibrillary tangles (NFTs), neuropil threads and Fahr-type calcification, in which no senile plaques are observed. As already noted, chronic exposure to lead (Pb) might be one of the etiological factors of Fahr-type calcification. Until now, there have been no reports in which Pb concentration has been quantified in DNTC brains. We examined the concentration of Pb in fresh-frozen brain tissue and in 10% formalin-fixed brain tissue from six cases of DNTC, four cases of Alzheimer's disease, and in nine non-demented elderly controls by flameless atomic absorption spectrometry, and demonstrated a high concentration of Pb in DNTC brains. Although it remains unclear how these findings are related to the formation of NFTs, they suggest that Pb neurotoxicity may be involved in the pathogenesis of DNTC.

Aged↗