Search PubMed⌕ Search

Biomedical subjects

T Nishikawa

Publications and source records attributed to T Nishikawa.

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

Lytic infection of Epstein-Barr virus (EBV) in hemophagocytic syndrome associated with EBV-induced lymphoproliferative disorder.

This report describes lytic infection with Epstein-Barr virus (EBV) in three cases of hemophagocytic syndrome (HPS) presumably associated with EBV-induced lymphoproliferative disorder. All cases were previously healthy females with ages ranging from 52 to 87 years who showed a fulminant clinical course with accompanying fever, liver dysfunction, and disseminated intravascular coagulation. Cases 1 and 2 showed proliferation of atypical T lymphocytes, and case 3 showed proliferation of atypical B lymphocytes. Hemophagocytic histiocytes were observed in the bone marrow, lymph nodes, spleen, and liver. Atypical lymphocytes in all cases showed a positive reaction for both EBV-encoded small RNA (EBER) indicating latent infection with EBV and immediate early mRNAs of the Bam HI fragment of lower stranded frame (BHLF), indicating lytic infection by in situ hybridization. Interestingly, BHLF-positive cells were predominant in all cases. It is possible that reactivation of EBV infection may be involved in triggering the induction of cytokines and abnormal activation of histiocytes.

Aged↗
PubMed2003

The combination of angiogenesis and blood vessel invasion as a prognostic indicator in primary breast cancer.

This study was undertaken to examine the interaction between the combination of angiogenesis and blood vessel invasion (BVI) and haematogenous metastasis, and to determine the prognostic significance of that combination in predicting 20-year relapse-free survival (RFS) and overall survival (OS) rates in primary breast cancer. Five hundred and nine patients were studied. We investigated 11 factors, including average microvessel count (AMC)/BVI, lymph-node status (n), clinical tumour size (T), histological grade (HG), lymphatic vessel invasion (LVI), p53, proliferating cell nuclear antigen (PCNA), c-erbB-2, mitotic index (MI), apoptotic index, and tumour necrosis (TN). Blood vessel invasion was detected by both factor VIII-related antigen and elastica van Gieson staining. To evaluate the best objective method to quantify microvessel density in angiogenesis, AMC was employed. The rate of AMC-high and BVI-positive tumours was 32.6 and 29.3%, respectively. That of both AMC-high and BVI-positive tumours was 10.1%. Univariate analysis showed that AMC/BVI, n, T, HG, LVI, p53, PCNA, MI, and TN were significantly predictive of RFS and OS. By multivariate analysis, AMC/BVI was the strongest independent prognostic factor for 20-year RFS (relative risk (RR)=5.5; P<0.0001) and for 20-year OS (RR=4.3; P<0.0001). Lymph-node status was still considered a powerful prognostic indicator; however, the combination of AMC and BVI provided more reliable prognostic information than lymph-node status for haematogenous dissemination.

Adolescent↗
PubMed2003

Effects of acetazolamide and 4-aminoprydine on the responses of deflationary slowly adapting pulmonary stretch receptors to CO2 inhalation in the rat.

The inhibitory effect of CO(2) on deflationary slowly adapting pulmonary stretch receptors (deflationary SARs) was investigated before and after administration of acetazolamide, a carbonic anhydrase (CA) inhibitor, or 4-aminopyridine (4-AP), a K(+) channel blocker, in anesthetized, artificially ventilated rats after unilateral vagotomy. CO(2) inhalation (maximum tracheal CO(2) concentration ranging from 9 to 12%) for approximately 60 s decreased the impulse activity of deflationary SARs but had no significant effect on tracheal pressure (P(T)) as an index of bronchomotor tone. Acetazolamide treatment (20 mg/kg) diminished the inhibitory response of deflationary SARs to CO(2) inhalation. 4-AP (0.7 and 2.0 mg/kg) dose-dependently attenuated the decrease in deflationary SAR activity induced by CO(2) inhalation. When comparing the maximum attenuation due to 4-AP (2.0 mg/kg) and acetazolamide (20 mg/kg) in CO(2)-induced deflationary SAR inhibition, blockade of K(+) channels had a more pronounced effect. These results suggest that inhibition of deflationary SARs by CO(2) inhalation may be largely mediated by the stimulating action of 4-AP-sensitive K(+) currents in the nerve terminals of the receptors.

4-Aminopyridine↗
PubMed2003

Distribution of anxiogenic-induced c-Fos in the forebrain regions of developing rats.

An anxiogenic or a pharmacological stressor, N-methyl-beta-carboline-3-carboxamide (FG-7142), (20 mg/kg, intraperitoneally injected) induced a dense nuclear c-Fos-like immunoreactivity in the pyriform cortex, cingulate and retrosplenial cortex, layers II-VI of the neocortex, lateral habenula, lateral septum, paraventricular nucleus of the thalamus, striatum, central and medial nucleus of the amygdala, but a sparse c-Fos immunostaining in the hippocampus and layer I of the neocortex in the forebrain of 56-day-old rats. Among these regions, the 8-day-old rats expressed much fewer c-Fos-positive cells in the neocortex, lateral habenula, lateral septum and medial nucleus of the amygdala than the young adult rats following the FG-7142 injection. These differences in the regional distribution of a neuronal activity marker, c-Fos, could reflect the postnatal development of neuronal populations or neuron circuits involved in stress and/or emotional response in the forebrain.

Aging↗
PubMed2003

Fentanyl decreases propofol requirement for laryngeal mask airway insertion.

BACKGROUND: Since fentanyl is a potent depressant of the upper airway reflex, preadministration of fentanyl may facilitate insertion of the laryngeal mask airway (LMA) using propofol. Accordingly, we tested the hypothesis that fentanyl pretreatment would reduce the dose of propofol required for the LMA insertion. METHODS: Forty-one healthy patients without sedative premedication were randomly assigned to either fentanyl group, receiving fentanyl 2 microg kg-1 intravenously, or control group, receiving equal volumes of normal saline. Then, 3 ml of 2% lidocaine was given intravenously to alleviate pain associated with propofol administration. Thirty s after the fentanyl or saline injection, a predetermined dose of 1% propofol was given at a rate of 100 mg min-1. Insertion of the LMA was attempted 90 s after the completion of the propofol injection. The dose of propofol given to a particular patient was determined by the response of the preceding patient in that group to a higher or lower dose, using the up-and-down method. The first patient in each group received 2.5 mg kg-1 of propofol, while the step-size was 0.25 mg kg-1. Patients responses were assessed by a blinded observer. RESULTS: ED50 and ED95 of propofol requirements were significantly less in the fentanyl group (0.82, 1.17 mg kg-1, respectively) than those in the control group (2.39, 2.62 mg kg-1, P < 0.001). CONCLUSION: Our results indicate that preadministration of fentanyl 2 microg kg-1 decreases the propofol requirement for the LMA insertion.

Adolescent↗
PubMed2003

A developmentally regulated and psychostimulant-inducible novel rat gene mrt1 encoding PDZ-PX proteins isolated in the neocortex.

Single or repeated exposure to psychostimulants such as amphetamines and cocaine after postnatal week 3 leads to an enduring enhancement in the psychotomimetic responses elicited by a subsequent challenge of a stimulant in rodents. This behavioral sensitization phenomenon has been considered to be the neural consequences of stimulant-induced alterations in gene expression in the brain after a critical period of postnatal development. Using a differential cloning technique, RNA arbitrarily primed PCR, we have now identified from the rat neocortex a novel and developmentally regulated methamphetamine (MAP)-inducible gene mrt1 (MAP responsive transcript 1). mrt1 encodes two major types of PDZ- and PX-domains containing proteins of approximately 62 kDa in size with different carboxy termini, Mrt1a and Mrt1b. The mrt1 mRNAs for Mrt1a, mrt1a, and for Mrt1b, mrt1b, are predominantly expressed in various brain regions and the testes, respectively. Acute MAP injection upregulated mrt1b expression in the neocortex after postnatal week 3 in a D1 receptor antagonist-sensitive manner without affecting mrt1a expression. This upregulation was mimicked by another stimulant, cocaine, whereas pentobarbital and D1 antagonist failed to change the mrt1b transcript levels. Moreover, repeated daily treatment of MAP, but not MAP plus D1 antagonist, for 5 days caused an augmentation of the basal expression of mrt1b 2 and 3 weeks after the drug discontinuation. These late-developing, cocaine-crossreactive, D1 antagonist-sensitive and long-term regulations of mrt1b by MAP are similar to the pharmacological profiles of stimulant-induced behavioral sensitization, and therefore may be associated with the initiation and/or maintenance of the long-term neuronal adaptation.

Aging↗
PubMed2003

Pyogenic lymphoma of the skin: a peculiar variant of primary cutaneous neutrophil-rich CD30+ anaplastic large-cell lymphoma. Clinicopathological study of four cases and review of the literature.

Systemic anaplastic large-cell lymphoma (ALCL) in human immunodeficiency virus (HIV)-infected individuals showing an extensive infiltrate of neutrophils has been reported and referred to as 'neutrophil-rich' CD30+ ALCL. Secondary cutaneous involvement has been found in a subset of these cases. We report the clinicopathological features of four immunocompetent patients with primary cutaneous neutrophil-rich ALCL and present a new histological subtype with a dissolute growth pattern of CD30+ tumour cells. Four HIV-negative patients presented with rapidly growing solitary or multiple tumours located on the face. Ulceration of the lesions with purulent discharge was a typical finding. Various inflammatory dermatoses were considered clinically in all cases. The histological hallmark was a large number of neutrophils in the infiltrate that masked neoplastic CD30+ anaplastic cells. In two cases, a dissolute growth pattern of anaplastic tumour cells was observed. In two cases, a strong correlation between tumour growth and interleukin (IL)-8 cytokine pattern as well as the production of IL-8 by tumour cells was demonstrated. The diagnosis of neutrophil-rich ALCL is challenging clinically and histologically as the tumour cell compartment is masked by an extensive inflammatory infiltrate of neutrophils and other reactive cells such as histiocytes which may be mainly due to release of IL-8 by tumour cells. The term 'pyogenic' designates the typical feature of this distinct neutrophil-rich ALCL, namely abscess formation ('pyo-') by cytokines (IL-8) produced by tumour cells ('-genic'). The clinical behaviour of this type is the same as in primary cutaneous CD30+ ALCL with classical histological presentation.

Abscess↗
PubMed2003

Lack of association of the interleukin-1 receptor antagonist gene with palmoplantar pustulosis in Japanese.

We analysed a polymorphism of the interleukin (IL)-1 receptor antagonist (IL1RN) gene in 93 Japanese patients with palmoplantar pustulosis (PPP). None of the IL1RN alleles was significantly increased in the patients compared with controls. Because PPP has been reported to be associated with the tumour necrosis factor (TNF) region, we examined the association between the TNF and IL1RN genes. There was a difference in IL1RN*2 positivity between patients with and without the AA genotype of the TNF gene. In contrast, such a difference was not found in controls. These data indicate a possible epistatic effect between TNF and IL1RN linked genes for susceptibility to the pathogenesis of PPP.

Adult↗
PubMed2003

Application of endoscopy for a midbrain tumor.

OBJECTIVE AND IMPORTANCE: It has been difficult to obtain a biopsy of a midbrain lesion. In addition, proper cerebrospinal fluid diversion should be secured because progressing tumor in the midbrain causes obstructive hydrocephalus. We report on the superiority of flexible neuroendoscopy to treat progressing midbrain tumor. CLINICAL PRESENTATION: A 64-year-old man presented with an occasional double vision. A magnetic resonance imaging scan disclosed an enhancing lesion in the midbrain. INTERVENTION: We performed a neuroendoscopic biopsy of the tumor and third ventriculostomy. Neuroendoscopy confirmed a bulging of the posterior commissure, which caused stenosis of the entrance of the aqueduct. Histological examination of the specimen obtained disclosed a diffuse astrocytoma. No permanent postoperative complications occurred although the patient felt slight double vision for 2 days after the operation. Conventional radiation therapy was supplemented. CONCLUSION: Flexible neuroendoscopic biopsy with third ventriculostomy was a less-invasive and safer alternative for the progressing midbrain tumor bulging into the ventricles.

Astrocytoma↗
PubMed2003

Unsuccessful third ventriculostomy for occlusive hydrocephalus.

For non-communicating hydrocephalus, neuroendoscopic third ventriculostomy has become a major choice. But sometimes, the procedure results in failure. Typically, impairment of a distal CSF absorption, a preexisting arachnoid membrane just below the fenestrated site and a glial scarring of fenestrated site were pointed out as a factors of failure. On the other side, the intraventricular pressure dynamics of a functioning third ventriculostomy is in the process of study. Recently some reports have noticed the importance of the flow of CSF into the prepontine cistern, mimicking the flow through the aqueduct of Sylvius. We report an unsuccessful trial of third ventriculostomy in a case with huge posterior fossa tumor.

Aged↗
PubMed2003

Immunomolecular mapping of adherens junction and desmosomal components in normal human epidermis.

Adherens junctions (AJs) are cell-cell and cell-matrix junctions that are known to comprise the transmembrane and cytoplasmic components linked to the f-actin cytoskeleton. Although the presence of AJs han been confirmed in normal human epidermis, previous studies immunolocalizing AJ-related antigens have been controversial. The purpose of this study was to produce a more precise molecular mapping of AJs and their constituents in relation to desmosomes in normal human epidermal keratinocytes. Using an electron microscope (EM) method to optimally fix plasma membranes. AJ structures were typically seen as a narrowing of the intercellular space between two keratinocytes that was distinct from desmosomes and gap junctions. Such structures were consistently found more frequently in the upper epidermis than in the basal layer. Immunogold electron microscopy showed an absence of the AJ components (E-cadherin and beta-catenin) from desmosomal areas but they were present at interdesmosomal areas at sites of close membrane association. Conversely, the desmosomal components plakoglobin and plakophilin 1 were restricted only to the outer attachment plaque of the desmosome. These results further confirm that AJs have a distinct molecular composition and distribution from desmosomes and that they regularly occur between desmosomes along the keratinocyte plasma membrane to provide alternative cell-cell adhesion mechanisms.

Actins↗
PubMed2003

Propofol requirement for insertion of cuffed oropharyngeal airway versus laryngeal mask airway with and without fentanyl: a dose-finding study.

BACKGROUND: The cuffed oropharyngeal airway (COPA) is a modified Guedel-type oral airway with a cuff at its distal end. The objectives of this prospective, randomized study were to compare the COPA and the laryngeal mask airway (LMA) in terms of propofol requirement with and without fentanyl pretreatment for smooth insertions. METHODS: Seventy-five patients undergoing general anaesthesia were randomly assigned to either a COPA (n=38) or LMA (n=37) group for airway management, and each group was further randomized to a saline-propofol or fentanyl-propofol group for anaesthesia induction. The saline-propofol group received i.v. saline and the fentanyl-propofol group received i.v. fentanyl 1 micro g kg(-1) followed 30 s later by i.v. propofol. Insertion of the device was attempted 90 s after propofol administration without the use of neuromuscular blocking agents or other adjuvants, and the responses of 'movement' or 'no movement' were judged by three observers blinded to the drug dose. Each dose of propofol at which insertion was attempted was predetermined by modification of Dixon's up-and-down method with 0.5 mg kg(-1) as the step size, and 2 mg kg(-1) as an initial dose. RESULTS: Without fentanyl pretreatment, propofol requirement [mean (SD), 95% CI] for COPA placement [2.17 (0.38), 1.77-2.56 mg kg(-1)] was significantly less than for LMA insertion [3.42 (0.26), 3.15-3.69 mg kg(-1), P<0.001]. In contrast, propofol requirements after fentanyl were comparable between the COPA and LMA groups [1.50 (0.42), 1.06-1.94 and 1.42 (0.26), 1.15-1.69 mg kg(-1), respectively], but were less than for the placebo group with both devices (P<0.05). Haemodynamic changes and duration of apnoea were similar with both devices irrespective of fentanyl pretreatment. CONCLUSIONS: Insertion of the COPA can be accomplished with a smaller bolus dose of propofol compared with the LMA, but propofol requirements are similar with both devices after a small dose of fentanyl.

Adolescent↗
PubMed2002

The complete sequence of the rice (Oryza sativa L.) mitochondrial genome: frequent DNA sequence acquisition and loss during the evolution of flowering plants.

The entire mitochondrial genome of rice (Oryza sativa L.), a monocot plant, has been sequenced. It was found to comprise 490,520 bp, with an average G+C content of 43.8%. Three rRNA genes, 17 tRNA genes and five pseudo tRNA sequences were identified. In addition, eleven ribosomal protein genes and two pseudo ribosomal protein genes were found, which are homologous to 13 of the 16 genes for ribosomal proteins in the mitochondrial genome of the liverwort (Marchantia polymorpha). A greater degree of variation in terms of presence/absence and integrity of genes was observed among the ribosomal protein genes and tRNA genes of rice, Arabidopsis and sugar beet. Transcription and post-transcriptional modification (RNA editing) in the rice mitochondrial sequence were also examined. In all, 491 Cs in the genomic DNA were converted to Ts in cDNA. The frequency of RNA editing differed markedly depending upon the ORF considered. Sequences derived from plastid and nuclear genomes make up 6.3% and 13.4% of the mitochondrial genome, respectively. The degree of conservation of plastid sequences in the mitochondrial genome ranged from 61% to 100%, suggesting that sequence migration has occurred very frequently. Three plastid DNA fragments that were incorporated into the mitochondrial genome were subsequently transferred to the nuclear genome. Nineteen fragments that were similar to transposon or retrotransposon sequences, but different from those found in the mitochondrial genomes of dicots, were identified. The results indicate frequent and independent DNA sequence flow to and from the mitochondrial genome during the evolution of flowering plants, and this may account for the range of genetic variation observed between the mitochondrial genomes of higher plants.

Biological Evolution↗
PubMed2002

Effects of prophylactic ankle supports on pronation during gait.

We performed a gait analysis of 12 healthy subjects in order to analyse the rear foot pronation-supination angle and the shift of centre of pressure (COP) during walking. We used a video system and a force plate and examined the effects of semi-rigid Air-Stirrup brace, lace-up cloth RocketSoc brace, ankle taping and no bracing. Both the lace-up cloth brace and taping increased the maximum pronation angle during the stance phase. The lace-up cloth brace alone was associated with a larger maximum pronation velocity. With the lace-up cloth brace and taping, the COP was more laterally placed, allowing greater leverage about the subtalar axis and thus increasing the tendency toward pronation. The two braces and the tape did not similarly affect ankle joint biomechanics during gait. The ability to reduce excessive amounts of pronation is an important design consideration for prophylactic ankle supports.

Adult↗
PubMed2002

Monitoring disease activity in pemphigus with enzyme-linked immunosorbent assay using recombinant desmogleins 1 and 3.

BACKGROUND: Pemphigus is an antidesmoglein (Dsg) autoimmune disease that is divided into two major subtypes: pemphigus foliaceus (PF) and pemphigus vulgaris (PV). We previously developed enzyme-linked immunosorbent assays (ELISAs) using recombinant Dsg1 and Dsg3 to detect IgG autoantibodies in patients with pemphigus. The protocol for the ELISAs was optimized for serological diagnosis, but under the conditions used, these assays were not particularly useful for monitoring disease activity in certain patients. That is, the sera from some patients with high-titre antibodies continued to show high index values in the ELISA after clinical improvement. OBJECTIVES: In the study reported here, we modified the ELISA protocol to obtain 'true' index values that exhibit a better correlation with disease activity. METHODS: We tested two cases of pemphigus foliaceus (PF) and four cases of pemphigus vulgaris (PV), each with ELISA index values greater than 150 for Dsg1 or Dsg3. We ran an ELISA with sera from these patients serially diluted from 1 : 100 to 1 : 12,800. We then performed ELISA with a series of PV No. 1 sera diluted to 1 : 800 and PV No. 2-4 and PF No. 1-2 sera diluted to 1 : 1600, after which we plotted the ELISA index values against the time course of disease activity. RESULTS: In each of these cases, there was no apparent decline, over the course of the disease activity, in the ELISA index values at a serum dilution of 1 : 100, probably because the antigen-antibody reaction was saturated at that dilution. After running an ELISA with sera serially diluted from 1 : 100 to 1 : 12,800 we found that a linear dose-dependency between the dilution value and the index value was only observed when sera were diluted to 1 : 800 or more in one case (PV No.1) and to 1 : 1600 or more in the other five cases (PV No. 2-4, PF No. 1-2). After performing ELISA with these series as outlined above we plotted the ELISA index values against the time course of disease activity and found that the index values obtained from these appropriately diluted sera fluctuated in parallel with disease activity, and declined with clinical improvement. CONCLUSIONS: These findings indicate that when appropriate dilutions are used in Dsg1 and Dsg3 ELISA, these assays can provide useful serological information for assessing disease activity in PF and PV.

Adult↗
PubMed2002

Laparoscopic adrenalectomy: comparison of transperitoneal and retroperitoneal approaches.

OBJECTIVE: To compare the effectiveness and efficiency of transperitoneal anterior laparoscopic adrenalectomy with that of retroperitoneal posterior laparoscopic adrenalectomy. PATIENTS AND METHODS: A retrospective comparison was undertaken of 28 patients who underwent transperitoneal anterior laparoscopy with 22 patients who underwent retroperitoneal posterior laparoscopy between April 1994 and November 2000. There were 18 men and 32 women (mean age 51.0 years, range 23-68) with varying diagnoses. Of the 50 patients, 31 had primary aldosteronism, eight had Cushing's syndrome, three had phaeochromocytoma, one had an 18-hydroxydeoxycorticosterone-induced adenoma and seven had non-functioning adrenal adenoma. Adrenal tumours were confirmed by hormonal assays, biochemical tests and computed tomography. To determine the site of the functioning adenoma, hormones were assayed from adrenal vein sampling. Thirty adrenal tumours were located on the right and 20 on the left. RESULTS: There were no significant differences in general demographic variables between the transperitoneal and retroperitoneal groups. The mean duration of surgery for transperitoneal and retroperitoneal laparoscopy was 202 and 221 min, respectively, and the mean blood loss 113 and 192 mL, respectively. The time to first oral intake, days to full diet, time until ambulatory and duration of hospitalization did not differ significantly between the two approaches. As the body mass index increased, the duration of surgery increased for both approaches. As more procedures were performed the duration of surgery decreased for both approaches. CONCLUSIONS: There were no significant differences between the transperitoneal and retroperitoneal approaches for laparoscopic adrenalectomy.

Adrenal Gland Diseases↗
PubMed2001

Comparison of sequences of cDNA clones obtained from oligo-capping cDNA libraries with those from unigene.

We compared in detail the characteristics of the sequences of the cDNA clones obtained by the oligo-capping method (oligo-capping clones) with that of the sequences in the UniGene database. To compare the completeness of the sequences, three new variables, "fullness-proportion of clones" (the ratio of complete clones to total clones in a library), "fullness-proportion of genes" (the ratio of complete genes to total genes in a library), and "fullness-proportion of database" (the ratio of complete genes to total genes in a database sampled from a library), were defined. The fullness-proportion of clones of oligo-capping clones was 57.3%, 2.2 times larger than that of UniGene (25.9%). The fullness-proportion of genes of oligo-capping clones was 41.8%, 2.4 times larger than that of UniGene (17.8%). When gene length was restricted to > or = 1.5 kb, the fullness-proportion of genes of oligo-capping clones was four times larger than that of UniGene. The fullness-proportion of database of oligo-capping clones was approximately the same as that of UniGene. By simulating the clone redundancy, this coincidence was found to be due to the large redundancy of the UniGene database. Consequently, the cDNA sequence database of oligo-capping clones enabled high throughput selection of full-length cDNA clones.

Algorithms↗