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Biomedical subjects

S Hirano

Publications and source records attributed to S Hirano.

At least 37 records · Page 2Linked to original sources
PubMed2001

Release of glycosaminoglycans in physiological saline and water by wet-spun chitin--acid glycosaminoglycan fibers.

The present study sought to prepare novel chitin- acid glycosaminoglycan fibers that released a portion of the glycosaminoglycans in animal body fluids for use as novel biocompatible dressing materials (artificial skin) in the veterinary and clinical fields. A clear solution of sodium N-acetylchitosan salt (alkaline chitin) mixed with sodium hyaluronate, sodium heparin, sodium chondroitin 4-sulfate, sodium chondroitin 6-sulfate, or sodium dermatan sulfate in 14% aqueous NaOH was spun through a viscose-type spinneret into a 10% aqueous H(2)SO(4) solution saturated with (NH(4))(2)SO(4) at room temperature. The result was chitin fibers containing 5--33% glycosaminoglycans. In a dry state these fibers were white and had a soft feel but they were mechanically weak (0.31--0.69 g/denier tenacity and 3.1--10.6% elongation). Portions (85--97%) of the glycosaminoglycans were released from the fibers by soaking them in physiological saline or distilled water. Scanning electron microscopy analyses revealed a smooth striped surface on the original filaments, and a scaly surface appeared on the chitin filament after soaking.

Animals↗
PubMed2001

Motor cortex stimulation for deafferentation pain.

OBJECT: The authors tested a modified motor cortex stimulation (MCS) protocol for the treatment of deafferentation pain in 15 patients: eight patients with poststroke pain, four with brachial plexus injury, two with phantom limb pain, and one with spinal cord injury. METHODS: Preoperative pharmacological tests were performed with phentolamine, lidocaine, ketamine, thiopental, morphine, and a placebo. In 12 patients we placed a 20- or 40-grid electrode in the subdural space to determine the best stimulation point for pain relief over a few weeks and therefore the optimum position for a permanent internal device. In four patients, the MCS devices were implanted in the interhemispheric fissure to reduce lower-extremity pain. In one patient, the MCS device was placed within the central sulcus, and a 20-grid electrode was placed on the brain surface. In two patients with pain extending from the upper extremity to the hyperbody, dual-electrode devices were implanted to drive two electrodes. In 10 of the 15 patients MCS-induced pain reduction was achieved (four with excellent, two with good, and four with fair alleviation of pain). The result of pharmacological testing indicated that patients with ketamine sensitivity seem to be good candidates for MCS. CONCLUSIONS: Test stimulation with a subdural multigrid electrode was helpful in locating the best stimulation point for pain relief.

Aged↗
PubMed2001

Oxidative damage to mitochondria is a preliminary step to caspase-3 activation in fluoride-induced apoptosis in HL-60 cells.

It has been suggested that oxidative stress plays a major role in various forms of cell death, including necrosis and apoptosis. We have previously reported that fluoride (NaF) induces apoptosis in HL-60 cells by caspase-3 activation. The main focus of this investigation was to arrive at a possible pathway of the apoptosis induced by NaF upstream of caspase-3, because the mechanism is still unknown. The present study showed that after exposure to NaF, there was an increase in MDA and 4-HNE and a loss of mitochondrial membrane potential (deltaPsi(m)) was also observed in NaF-treated cells. There was a significant increase in cytosolic cytochrome c, which is released from the mitochondria. We have reported a downregulation of Bcl-2 protein in NaF-treated cells. The antioxidants N-acetyl cysteine (NAC), glutathione (GSH) protected the cells from loss of deltaPsi(m), and there was no cytochrome c exit or Bcl-2 downregulation, and we suggest that these antioxidants prevent apoptosis induced by NaF. These results suggested that perhaps NaF induced apoptosis by oxidative stress-induced lipid peroxidation, causing loss of deltaPsi(m), and thereby releasing cytochrome c into the cytosol and further triggering the caspase cascade leading to apoptotic cell death in HL-60 cells.

Acetylcysteine↗
PubMed2001

Up-regulation of E2F-1 in Down's syndrome brain exhibiting neuropathological features of Alzheimer-type dementia.

We studied the expression of the apoptosis-related protein, E2F-1, in Down's syndrome (DS) brains. The immunoreactivity for E2F-1 was detected in the pyramidal neurons of the cerebral cortex from DS brains exhibiting the neuropathological features of dementia of Alzheimer type (DAT), in accordance with the amyloid beta protein (A beta) deposition in the neuron. Therefore, the implication is that A beta deposition may trigger E2F-1-mediated neuronal apoptosis in DS brains with DAT.

Adolescent↗
PubMed2001

Isolation of Dlx and Emx gene cognates in an agnathan species, Lampetra japonica, and their expression patterns during embryonic and larval development: conserved and diversified regulatory patterns of homeobox genes in vertebrate head evolution.

Agnathan cognates of vertebrate homeobox genes, Emx and Dlx, were isolated from embryonic cDNA of a Japanese marine lamprey, Lampetra japonica. Analyses of amino acid sequences indicated that the Dlx cognate was closely related to the common ancestor of gnathostome Dlx1 and Dlx6 groups and termed LjDlx1/6. Southern blot analyses could not rule out the possibility that L. japonica possesses more than one paralog for both LjDlx1/6 and LjEmx, the lamprey cognate of Emx. Expression of LjDlx1/6 was regulated spatially as well as developmentally, and its transcripts were mainly found in the craniofacial and pharyngeal mesenchyme and in the forebrain. The expression pattern of LjEmx changed dramatically during embryogenesis; expression was seen initially in the entire neural tube and mesoderm, which were secondarily downregulated, and secondarily in cranial nerve ganglia and in the craniofacial mesenchyme. No specific expression of LjEmx was seen in the telencephalon. Comparisons of Dlx and Otx gene expression patterns suggested a shared neuromeric pattern of the vertebrate brain. Absence of Emx expression implied that the patterning of the lamprey telencephalon is not based on the tripartite plan that has been presumed in gnathostomes. Expression domains of LjDlx1/6 in the upper lip and of LjEmx in the craniofacial mesenchyme were peculiar features that have not been known in gnathostomes. Such differences in expression pattern may underlie distinct morphogenetic pathway of the mandibular arch between the agnathans and gnathostomes.

Amino Acid Sequence↗
PubMed2001

Nonlinear digital hearing aid with near-instantaneous amplitude compression.

We designed a new type of nonlinear digital hearing aid (TD-1) with near-instantaneous amplitude compression for sensorineural hearing-impaired people. The amplification method utilized by the TD-1 normalizes the signal waveforms within a time window bounded by two adjacent positive going zero-crossing points. The signals within this window are amplified so that the maximum amplitude reaches a preset value, thus allowing a consistent peak amplitude to be maintained. To test this, we examined the efficacy of the TD-1 device in 31 patients with sensorineural hearing loss. When tested for recognition of Japanese sentences in a quiet environment, 7 of 25 (28.0%) subjects wearing the TD-1 showed a 20% or greater increase in the maximum intelligibility score than that obtained when wearing their own linear hearing aids. In addition, 7 of 31 (22.6%) subjects showed the same increase with the TD-1 relative to that obtained when they wore HA70 or HA73 devices (Rion Co., Ltd., Tokyo, Japan), which are conventional analogue hearing aids. These results indicate that TD-1 can be effective for patients with sensorineural hearing loss.

Adolescent↗
PubMed2001

Granule cell raphes in the developing mouse cerebellum.

The cerebellar cortex of many vertebrates shows a striking parasagittal compartmentation that is thought to play a role in the establishment and maintenance of functional cerebellar connectivity. Here, we demonstrate the existence of multiple parasagittal raphes of cells in the molecular layer of the developing cerebellar cortex of postnatal mouse. The histological appearance and immunostaining profile of the raphe cells suggest that they are migrating granule cells. We therefore conclude that the granule cell raphes previously described in birds also exist in a mammalian species. The raphes in mouse are visible on nuclear stains from around birth to postnatal day 6 and are frequently found at the boundaries of Purkinje cell segments that differentially express cadherins ("early-onset" parasagittal banding pattern). A similar relation between the raphe pattern and various markers for the early-onset banding pattern has been found in the chicken cerebellum. One of the cadherins mapped in the present study (OL-protocadherin) continues to be expressed in specific Purkinje cell segments until at least postnatal day 14. At this stage of development, the borders of the OL-protocadherin-positive Purkinje cell segments coincide with the borders of Purkinje cell segments that express zebrin II, a marker for the "late-onset" parasagittal banding pattern which persists in the adult cerebellum. These findings demonstrate that the early-onset banding pattern, as reflected in the complementary arrangement of raphes/Purkinje cell segments, and the late-onset pattern of zebrin II expression share at least some positional cues during development.

Animals↗
PubMed2001

Portal venous dilatation and stenting for bleeding jejunal varices: report of two cases.

We present two patients who underwent a portal stent placement for bleeding jejunal varices of the afferent loop caused by extrahepatic portal venous stenosis. Case 1 involved a 66-year-old woman who developed bleeding jejunal varices due to extrahepatic portal venous stenosis 1 year after a pancreaticoduodenectomy with intraoperative radiation therapy. Percutaneous transhepatic balloon dilatation and stent placement were performed. Since undergoing the procedure, no bleeding has occurred. Case 2 concerned a 44-year-old woman who had a rupture and bleeding of jejunal varices 16 years after a choledocojejunostomy. Stenosis was observed from the right and left branches of the portal vein to its intrahepatic branches. Both balloon dilatation and stent placement were attempted. However, the stent could not be fully inserted into the intrahepatic portal vein. Portal stent placement is less invasive and radical, and therefore should be attempted for the treatment of extrahepatic portal venous stenosis. However, there are limits to its application if the stenosis extends to the intrahepatic branches of the portal vein.

Adult↗
PubMed2001

Is interpersonal sensitivity specific to non-melancholic depressions?

BACKGROUND: We investigated whether melancholic and non-melancholic Japanese depressive patients differed in regard to a personality feature, interpersonal sensitivity, as measured by the Interpersonal Sensitivity Measure (IPSM). METHODS: In addition to 154 normal controls, 66 remitted melancholic patients and 55 remitted non-melancholic patients filled out the IPSM and two widely-used comprehensive personality inventories, the Temperament and Character Inventory (TCI) and the Munich Personality Test (MPT). The subdivision of patients was made according to three major symptom-based criteria for melancholia (those of RDC, DSM-III, DSM-IV). RESULTS: Multivariate and post-hoc univariate analyses of variance revealed significant differences among the three groups in several personality dimensions after Bonferroni's adjustments of P values. While reported scores of both melancholic and non-melancholic patients deviated from normative scores on several personality dimensions, non-melancholic patients reported significantly higher scores on the total IPSM and the 'fragile inner-self' (a subscore of the IPSM) than did normal controls or melancholic depressives. The principal component analysis isolated two factors related to depressive disorders: one factor corresponding to the five IPSM scores; and the other corresponding to harm avoidance, neuroticism and frustration tolerance. The scores on the former factor differentiated non-melancholic depressives from melancholic depressives and normal controls. The scores on the latter factor differentiated both melancholic and non-melancholic depressives from normal controls. LIMITATIONS: Prospective studies in which depressive subjects are subdivided into melancholic and non-melancholic subjects will be required to see whether the personality deviations here related to depressive disorders strongly reflect the premorbid personality function. CONCLUSIONS: These results indicate that the IPSM scales (particularly, the fragile inner-self scale and the total IPSM scale) are relatively independent of all dimensions included in the two comprehensive personality inventories, and have a capability to describe personality differences between non-melancholic depression and melancholia.

Adult↗
PubMed2001

Assessment of styrene oligomers eluted from polystyrene-made food containers for estrogenic effects in in vitro assays.

Recently, several substances from among the huge numbers of chemicals used by mankind have been implicated as instigators of disrupted endocrine function and related human health problems. Polystyrene (PS) is one of the most frequently used resins in the world, and the styrene oligomer dissolved out from PS has been designated as a potential trigger of estrogen-like activity in the Wingspread Declaration and the Japan Environment Agency's SPEED98 [JEA (Japan Environment Agency) Strategic Problem on Environmental Endocrine Disruptors '98 (SPEED) '98), http://www.env.go.jp/en/pol/speed98/sp98.html]. In order to assess the endocrine disrupting effect of styrene oligomers, we tested one styrene monomer (SM), three styrene dimers (SDs) and seven styrene trimers (STs), newly isolated from optical isomers, known to dissolve in small amounts from cup noodle containers made of polystyrene by the estrogen receptor binding assay, luciferase reporter gene assay, and human breast cancer cell MCF-7 proliferation assay. In all three tests, none of the SM, SDs and STs showed any significant activity. Accordingly, we concluded that these substances have no estrogenic activity.

Animals↗
PubMed2001

Clinical and pedigree study on familial cases of West syndrome in Japan.

Nationwide survey on familial cases of West syndrome (WS) in first- and second-degree relatives was conducted by mailing a questionnaire to 64 major university hospitals, children's hospitals, and epilepsy centers in Japan, and by review of the Japanese cases in the literatures. Thirty-four familial cases, 20 males and 14 females, were obtained in 15 families including one with five affected members in two generations and another with three affected male siblings including a half brother by a different father (X-linked WS). A mother and the child or children were involved in three families. Nine families had 21 cryptogenic cases and six families had 13 symptomatic cases, and the etiologies were same among the affected members in each family. Familial cases of WS have characteristic clinical features and genetic mechanisms. Age of onset, seizure types, electroencephalographic abnormalities, early seizure outcome, effective treatment, long-term seizure prognosis, and long-term developmental prognosis were concordant among the affected members in each family. Long-term seizure and developmental prognoses were far better than those in WS in general, with seizure-free rate of 82% and normal mental development rate of 44%. Poor prognosis was limited to specific symptomatic cases. Adrenocorticotropic hormone (ACTH) was a treatment of choice, and even in relapse of WS after ACTH therapy, the patients well responded to antiepileptic drugs. Specific inheritance pattern was difficult to imagine in the majority of the present cases, except for one family with X-linked WS and another family with five patients of maternal inheritance. These results are helpful for the treatment choice and prognostication of clinical course for familial cases of WS.

Adrenocorticotropic Hormone↗
PubMed2001

Identification, determination, and biological evaluation of a novel styrene trimer contained in polystyrene food containers. 2.

An unidentified styrene trimer (ST) isolated from the acetonitrile extract of polystyrene (PS) food containers was characterized as (1S*,6R*,7S*,8S*,11R*)-6,11-diphenyltricyclo[6,2,2,0(2,7)]dodeca-2,9-diene. The content and migration of this compound in PS food containers were determined by GC-MS (SIM). Furthermore, an endocrine-disrupting effect was tested using in vitro and in vivo assays of the compound. In conclusion, it seems that the compound does not present the effect.

Animals↗
PubMed2001

Transitional cell carcinoma of the renal pelvis in a long-term hemodialysis patient with autosomal dominant polycystic kidney.

We present a case of renal pelvic transitional cell carcinoma (TCC) accompanied by autosomal dominant polycystic kidney disease (ADPKD). An 81-year-old woman on long-term hemodialysis for ADPKD visited the Department of Urology at Kouseiren Takaoko Hospital, complaining of asymptomatic macroscopic hematuria. Retrograde pyelogram showed an irregular filling defect in the right renal pelvis, which suggested the right renal pelvic tumor. We performed right nephrectomy and transurethral removal of the right ureter. Histological diagnosis demonstrated renal pelvic TCC.

Aged↗
PubMed2001

Tracing axons in the peripheral nerve using lacZ gene recombinant adenovirus and its application to regeneration of the peripheral nerve.

The usefulness of recombinant adenovirus with LacZ to trace axons in the peripheral nervous system was investigated. Recombinant adenovirus with LacZ was applied to the cut end of the tibial nerve in rats. The LacZ gene product (B-galactosidase) filled axons of the tibial nerve, which permitted the continuous long-range tracing of axons. Further, the branching and the direction of the branches could also be examined. Labeled axons in the tibial nerves ran parallel to each other without branching and kept this relative position in the tibial and the sciatic nerve. When the virus was introduced to the regenerating nerve using a silicon tube, the regenerating fibers grew tortuously with short branches in the bulge at the proximal end of the silicon tube. The fibers grew straight in the tube and passed through the bulge at the distal end of the tube without branching. These observations indicate that the LacZ gene recombinant adenovirus is a useful tracer for the study of the peripheral nervous system and of the regeneration processes.

Adenoviridae↗
PubMed2001

Identification and expression of the lamprey Pax6 gene: evolutionary origin of the segmented brain of vertebrates.

The Pax6 gene plays a developmental role in various metazoans as the master regulatory gene for eye patterning. Pax6 is also spatially regulated in particular regions of the neural tube. Because the amphioxus has no neuromeres, an understanding of Pax6 expression in the agnathans is crucial for an insight into the origin of neuromerism in the vertebrates. We have isolated a single cognate cDNA of the Pax6 gene, LjPax6, from a Lampetra japonica cDNA library and observed the pattern of its expression using in situ hybridization. Phylogenetic analysis revealed that LjPax6 occurs as an sister group of gnathostome Pax6. In lamprey embryos, LjPax6 is expressed in the eye, the nasohypophysial plate, the oral ectoderm and the brain. In the central nervous system, LjPax6 is expressed in clearly delineated domains in the hindbrain, midbrain and forebrain. We compared the pattern of LjPax6 expression with that of other brain-specific regulatory genes, including LjOtxA, LjPax2/5/8, LjDlx1/6, LjEmx and LjTTF1. Most of the gene expression domains showed conserved pattern, which reflects the situation in the gnathostomes, conforming partly to the neuromeric patterns proposed for the gnathostomes. We conclude that most of the segmented domains of the vertebrate brain were already established in the ancestor common to all vertebrates. Major evolutionary changes in the vertebrate brain may have involved local restriction of cell lineages, leading to the establishment of neuromeres.

Amino Acid Sequence↗
PubMed2001

Evaluation of 13C-phenylalanine and 13C-tyrosine breath tests for the measurement of hepatocyte functional capacity in patients with liver cirrhosis.

Liver disease is associated with an abnormal elevation of the plasma concentrations of the aromatic amino acids phenylalanine and tyrosine. The liver is the main site of aromatic amino acid metabolism, particularly the hydroxylation of phenylalanine to tyrosine and further tyrosine degradation. In the present study, we have examined the usefulness of the L-[1-13C]phenylalanine breath test (13C-PheBT) and L-[13C]tyrosine breath test (13C-TyrBT) for the detection of hepatic damage in patients with liver cirrhosis. First, the time courses of 13CO2 excretion after the administration of L-[1-13C]phenylalanine and L-[1-13C]tyrosine were compared. The peak times (the time expressed in minutes at which 13CO2 excretion was maximal) were 20 min in both breath tests, but 13C-TyrBT gave a higher peak than 13C-PheBT. Next, the parameters of 13C-PheBT and 13C-TyrBT were compared with biochemical liver function test values. These parameters were well correlated with several liver blood test values conventionally regarded as measures of hepatocyte functional reserve. Therefore, 13C-PheBT and 13C-TyrBT may be useful to assess the degree and progression of hepatic dysfunction.

Adult↗
PubMed2001

Localization of zinc after in vitro mineralization in osteoblastic cells.

The present study was designed to investigate the incorporation of zinc (Zn) into cultured UMR-106 osteoblasts in response to mineralization caused by the addition of beta-glycerophosphate. As a result of the induced mineralization, the contents of calcium (Ca), phosphorus (P), and Zn in the monolayer increased, whereas the magnesium (Mg) content did not change. The activity of alkaline phosphatase (ALP) also increased during the process. The zinc distribution in the cell monolayer was studied using Zinquin, a fluorescent zinc ion chelator. The double fluorescent labeling with Zinquin and calcein revealed that zinc was localized both as intracellular vesicles and extracellular clusters, whereas calcium was colocalized with extracellular zinc. These results suggest that zinc is involved in the mineralization process of UMR-106 cells.

Alkaline Phosphatase↗