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Biomedical subjects

K Sano

Publications and source records attributed to K Sano.

At least 199 records · Page 11Linked to original sources
PubMed1999

[Changes in tracheal and lung sounds before and after resection of adenoid cystic carcinoma of the trachea].

A 79-year-old woman was admitted to our hospital with complaints of wheezing and dyspnea. Adenoid cystic carcinoma was diagnosed from the findings on biopsy specimens obtained by fiberoptic bronchoscopy. The tumor was resected and end-to-end anastomosis was performed. Precision analyses of lung sounds were conducted before and after the operation. During eupnea the tracheal sounds prior to operation contained an accentuated, high-frequency component at about 1,500 Hz. The tracheal sounds included a single monophonic wheeze during deep inspiration and 5 wheezes during forced expiration. By contrast, lung sounds in the chest wall were almost normal both before and after the operation. We concluded that increases in high-frequency components in tracheal sounds and the manifestation of various wheezes can be useful in diagnosing tracheal stenosis and/or tumors.

Aged↗
PubMed1998

Inducibility of BDNF gene promoter I detected by calcium-phosphate-mediated DNA transfection is confined to neuronal but not to glial cells.

Although DNA transfection with calcium-phosphate/DNA precipitates for promoter analysis of genes has been previously applied to primary cultures of neuronal cells, it remains uncertain whether the expression of the introduced genes in glial cells, which are also in primary culture, affects the transcriptional signals obtained. Using plasmid DNA containing the brain-derived neurotrophic factor (BDNF) gene promoter I or c-fos promoter, we investigated the optimum conditions for calcium-phosphate-mediated DNA transfection in primary culture of rat cortical neuronal cells. Normalizing the firefly luciferase activity of the experimental reporter gene to the Renilla luciferase activity of the internal control increased experimental reliability. Maximum expression of firefly luciferase activity in the cells stimulated by membrane depolarization required 6-12 hrs of incubation after stimulation. Differences in the ratio of the experimental reporter gene to the internal control did not affect experimental gene expression. Under our optimal conditions, the activation of the BDNF gene promoter I was detected in neuronal but not in glial cells. Calcium-phosphate-mediated DNA transfection should be widely applicable for promoter analysis of inducible genes in neurons.

Animals↗
PubMed1998

Elevation of the serum Fas ligand in patients with hemophagocytic syndrome and Diamond-Blackfan anemia.

Fas ligand (FasL) is a membrane protein that is expressed in activated T cells and natural killer cells. FasL binds to Fas on target cells and induces apoptosis. There exists a soluble form of FasL (sFasL), and sFasL also induces apoptosis of Fas-bearing cells. The serum sFasL concentrations were reported to be elevated in patients with large granular lymphocytic leukemia and natural killer cell lymphoma. In this study, we have measured serum sFasL concentrations in other hematological disorders, including severe aplastic anemia (SAA), hemophagocytic lymphohistiocytosis (HLH), and Diamond-Blackfan anemia (DBA). The serum sFasL concentration of age-matched healthy controls was 0.16 +/- 0.11 ng/mL (mean +/- SD, n = 22). The serum sFasL levels in the patients with HLH and DBA were 3.75 +/- 3.82 (n = 19; P < .0001, HLH v control) and 2.76 +/- 2.43 ng/mL (n = 6; P = .012, DBA v control), respectively. Serum interferon-gamma concentration was elevated in the patients with HLH (1.61 +/- 2.62 ng/mL) but not in those with DBA (below the detectable level). These results suggest that the Fas-FasL system plays a role, at least in part, in the pathophysiology of HLH and DBA.

Adolescent↗
PubMed1998

Pyridine nucleotide levels in liver of rats fed clofibrate- or pyrazinamide-containing diets.

Hepatic NAD+, NADH, and NADPH were increased significantly 3 days after feeding rats with a 0.25% clofibrate diet, increased further after 8 days, and stayed at the same levels 14 days after feeding the diet. The NAD+/NADH ratio was decreased significantly by feeding the clofibrate diet for 8 days, while the ratio remained unchanged with a 1% pyrazinamide diet. Hepatic quinolinate phosphoribosyltransferase (QAPRTase) (EC 2.4.2.19) activity was increased to 1.8 and 1.3 times that of the control animals in the clofibrate- and the pyrazinamide-fed rats, respectively, while hepatic aminocarboxymuconate-semialdehyde decarboxylase (ACMSDase) (EC 4.1.1.45) activity was decreased to 0 and 19% of that of the control animals. The heat-treated liver homogenate from the pyrazinamide-fed rats contained inhibitory activity toward ACMSDase, while no inhibitory activity was found in the liver homogenate of the clofibrate-fed animals. We conclude that these changes of enzyme activities, which seem due to different mechanisms, may contribute to the increase of pyridine nucleotides in the liver of rats fed clofibrate or pyrazinamide.

Animals↗
PubMed1998

Double intratracheal instillation of keratinocyte growth factor prevents bleomycin-induced lung fibrosis in rats.

Alveolar re-epithelialization is necessary in the repair of damaged alveolar epithelium after lung injury. Keratinocyte growth factor (KGF) has been shown to be a potent proliferation and differentiation factor for rat alveolar type II cells. The present study examined whether KGF would prevent bleomycin-induced lung fibrosis. Adult rats were anaesthetized and recombinant human KGF (rhKGF) (150 micrograms/kg) or saline was injected intratracheally at 48 h before and 24 h after bleomycin (Bleo, 5 mg/kg) instillation. Seven and 14 days after the last administration, rat lungs were processed for lung physiology, immunohistochemistry, and in situ hybridization. Double instillation of KGF prevented the loss of body weight and reduction in total lung capacity (TLC) due to Bleo, and markedly attenuated the protein accumulation and mRNA expression of collagen types I and III and the decreased expression of surfactant protein mRNAs in the fibrotic lesions of Bleo-treated rats. KGF may play an important role in maintaining alveolar epithelium and repairing the damaged epithelium after lung injury.

Animals↗
PubMed1998

Long acellular nerve transplants for allogeneic grafting and the effects of basic fibroblast growth factor on the growth of regenerating axons in dogs: a preliminary report.

Sciatic nerves were excised from 3 beagle dogs about 5 h after their sacrifice, treated three times by freezing and thawing, and stored in physiological saline for 3 months at -20 degrees C until used. Nerve segments 5 cm in length prepared from these stored nerves were transplanted to the common peroneal nerve in the right hindlimb of beagle dogs. Sixteen beagle dogs in total were used, in four treatment groups of two pairs each studied at 1 and 3 months. Five-hundred microliters basic fibroblast growth factor (bFGF) of two different concentrations (10 micrograms/300 microliters and 100 micrograms/300 microliters) which were impregnated in 0.5 ml gelatin hydrogels was applied around the sutured allografts. Autografting was also done in 4 beagle dogs, with no bFGF application. One month after the grafting, no regenerating nerves extended beyond the middle of the transplant in any of the allografts, except in the autografts in which a number of regenerated (myelinated) axons were present. Three months after the grafting, an abundance of myelinated axons was found at the middle of the graft: the numbers of axons per 10(4) micron 2 were 22.6 in the autografts and 10.6, 10.4 and 19.2 in the allografts treated with no bFGF, low-dose bFGF, and high-dose bFGF, respectively. Regenerating axons extended into the host nerve: the numbers of myelinated axons at the level 1.5 cm distal to the distal suture were 35.7, 0.9, 3.8, and 12.1 per 10(4) micron 2 in the above respective order. Although it was inferior in quality to the autograft, peripheral nerve regeneration was extensive in the distal nerve using freeze-thawed and bFGF-treated allografts at 3 months. Electromyography showed that the peroneus longus muscle responded to the electrical stimuli given at the site proximal to the transplant in all four groups. These data indicate that a 5-cm acellular nerve segment containing Schwann cell basal laminae can be used successfully as an allograft without any immunosuppressants and that exogenously applied bFGF can improve nerve regeneration by enhancing the growth of regenerating axons.

Animals↗
PubMed1998

Chemoenzymatic synthesis of an N-acetylneuraminic acid analogue having a carbamoylmethyl group at C-4 as an inhibitor of sialidase from influenza virus.

5,9-Diacetamido-2,6-anhydro-O-4-carbamoylmethyl-3,5,9-trideo xy-D-glycero- D-galacto-non-2-enonic acid (1) was synthesized via a key intemediate 2 through the Neu5Ac aldolase [E.C.4.1.3.3]-catalyzed aldol reaction of 2-acetamido-2,6-dideoxy-6-azido-D-glucose with sodium pyruvate operating under alkaline conditions (pH 10.5) in order to accelerate epimerization C-2 of N-acetyl-D-glucosamine (D-GlcNAc) derivatives. Compound 1 showed inhibitory activity against sialidase.

Enzyme Inhibitors↗
PubMed1998

Translocation (10;12)(q24;q15) in a T-cell lymphoblastic lymphoma with myeloid hyperplasia.

We present a case of childhood T-cell lymphoblastic lymphoma (T-LBL) with a translocation (10;12)(q24;q15) as a main clonal abnormality, which to our knowledge is the first reported karyotype of this malignancy. The patient's peripheral blood and bone marrow showed marked leukocytosis mostly myeloid lineage cells, at diagnosis. The enlarged lymph node consisted of two different cell populations: CD2+/CD7+ prothymic lymphoblasts and a cluster of peroxidase-positive myeloid cells around vessels. This case might represent a rare but distinct clinical entity of LBL.

Adolescent↗
PubMed1998

Contrast-enhancement for the image of human immunodeficiency virus from ultrathin section by immuno electron microscopy.

A simple contrast-enhancement method is described for electron microscopic imaging of the human immunodeficiency virus (HIV) from a sample embedded in Lowicryl K4M resin, by immuneelectron microscopy. Ultrathin sections were treated with a mixture of ruthenium red dye (RR) and osmium tetroxide (OSO4). This treatment provided good contrast enhancement of the entire ultrastructural image of virus particles without the loss of immunolabelling. RR/OsO4 solution is simple to prepare and provides a better contrast than that which is achieved during conventional post-embedding immunoelectron microscopy. Treatment of ultrathin sections from low temperature-embedded samples with RR/OsO4 solution is recommended.

Cell Line↗
PubMed1998

Simple X-ray film holder for lateral view of the anterior jaws using dental X-ray apparatus.

A new X-ray apparatus, the occlusal X-ray film holder, was devised so that the lateral view of the jaw could be studied. This apparatus could easily be adjusted to a dental X-ray cone. In 21 cases of impacted teeth, cysts or foreign body in the maxilla and mandible and 6 cases that necessitated examination before or after implantation, the efficacy of this apparatus was confirmed. Its advantages are: it is applicable to dental X-ray equipment; it is cheap; there is no need for image intensifying to get a clear image; and follow-up examination is possible. We believe that this film holder would be useful for the diagnosis of lesions in the anterior maxilla and mandible as well as in the general dental clinic.

Foreign Bodies↗
PubMed1998

The anti-tumor effect of photodynamic therapy evaluated by bromodeoxyuridine immunohistochemistry.

The anti-tumor effect of photodynamic therapy (PDT) on mouse tumors was evaluated with bromodeoxyuridine (BrdU) immunohistochemistry. BrdU was injected into the mice intraperitoneally (40 mg/kg body weight). Immediately after injection of BrdU, PDT using a photosensitizing drug (hematoporphyrin oligomers: 20 mg/kg body weight) was carried out on the experimental group but not on the control group. BrdU labeling indices (LIs) of the tumor cells close to blood vessels and adjacent to the surrounding normal tissue were investigated. In the tumor cells close to blood vessels, the LIs of the experimental group were significantly lower than those of the control group. As for the tumor cells adjacent to the surrounding normal tissue, the LIs of the experimental group were similar to those of the control group. Thus, the effect of PDT was significant in the tumor cells close to the blood vessels, while the tumor cells adjacent to the surrounding normal tissue resisted PDT.

Animals↗
PubMed1998

A comparative study of epithelialization of subcutaneous fascial flaps and muscle-only flaps in the oral cavity. A rabbit model.

Epithelialization of subcutaneous fascial flaps and muscle-only flaps used for reconstruction of the oral mucosa were studied in a rabbit model. Angiography was performed to help to design a subcutaneous cervical fascial flap and a cleidomastoid muscle-only flap. These flaps were transferred into a mucoperiosteal defect on the mandibular alveolus. The flaps were gradually infiltrated by acute inflammatory cells from the periphery and then replaced by granulation tissue originating from the oral mucosa. The epithelialization was by secondary intention. An epithelial tongue from the surrounding epithelium migrated onto the granulating flaps with eventual coverage after three weeks. After two months, the muscle-only flap was covered by a poorly organized epithelium, different from the highly uniform epithelium in the fascial flap. The granulation tissue which replaced the muscle-only flap matured to fibrous tissue, associated with severe contraction. This was characterized by dense regular collagen fibers, no elastic fibers, and few capillaries, while the fibrous tissue which replaced the fascial flap was characterized by random collagen and elastic fiber morphology and numerous dilated blood vessels, and was associated with mild contraction. This experiment supports the view that the different extracellular matrices of these flaps may play a role in epithelial configuration and contraction.

Animals↗
PubMed1998

Cloning of tropomyosins from lobster (Homarus americanus) striated muscles: fast and slow isoforms may be generated from the same transcript.

Complementary DNAs encoding fibre-type-specific isoforms of tropomyosin (Tm) have been isolated from lobster (Homarus americanus) striated muscle expression libraries made from poly(A)+ RNA purified from deep abdominal (fast-type) and crusher-claw closer (slow-type) muscles. A cDNA of slow-muscle Tm (sTm1), containing a complete open reading frame (ORF) and portions of the 5' and 3' untranslated regions (UTRs), encodes a protein of 284 amino acid residues with a predicted mass of 32,950, assuming acetylation of the amino terminus. The nucleotide sequence of a fast-muscle tropomyosin (fTm cDNA), which includes the entire ORF and part of the 3' UTR, is identical to that of sTm1 cDNA, except in the region encoding amino acid residues 39-80 (equivalent to exon 2 of mammalian and Drosophila muscle tropomyosin genes). The deduced amino acid sequences, which display the heptameric repeats of nonpolar and charged amino acids characteristic of alpha-helical coiled-coils, are highly homologous to tropomyosins from rabbit, Drosophila, and shrimp (57% to 99% identities, depending on species). Northern blot analysis showed that two transcripts (1.1 and 2.1 kb) are present in both fibre types. Mass spectrometry indicated that fast muscle contains one major isoform (fTm: 32,903), while slow muscle contains two major isoforms (sTm1 and sTm2: 32,950 and 32,884 respectively). Both Tm preparations contained minor species with a mass of about 32,830. Sequences of peptides derived from purified slow and fast Tms were identical to the deduced amino acid sequences of the sTm1 and fTm cDNAs, respectively, except in the C-terminal region of fTm. The difference in mass between that predicted by the deduced sequence (32,880) and that measured by mass spectrometry (32,903) suggests that fTm is posttranslationally modified, in addition to acetylation of the N-terminal methionine. These data are consistent with the hypothesis that the fTm and sTm1 are generated by alternative splicing of two mutually-exclusive exons near the 5' end of the same gene.

Abdominal Muscles↗
PubMed1998

Protein W, a spore-specific protein in Myxococcus xanthus, formation of a large electron-dense particle in a spore.

The gene for the major spore-specific protein, termed protein W, was cloned, and it was found that protein W is composed of 426 amino acid residues including 31% charged (133 residues) and 39% hydrophobic (166 residues) amino acids. In the protein, a motif consisting of five amino acid residues [(V/L/I)-R-E-R-(V/L/I)] is repeated 28 times, and another motif [M-M-(P/G)-Q-G] five times. Protein W is synthesized during a very late stage of development, forming a single, large electron-dense particle (200-400 nm in diameter) inside a spore. X-ray microanalysis of the particle revealed that it contains a high amount of phosphate in addition to calcium and magnesium. It is proposed that protein W consisting of highly charged repetitive sequences is a polyphosphate storage protein to store energy in spores. The disruption of the gene for protein W resulted in delayed fruiting body formation and a lower spore yield.

Amino Acid Sequence↗