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Biomedical subjects

M Takayama

Publications and source records attributed to M Takayama.

At least 19 recordsLinked to original sources
PubMed2001

Serum insulin-like growth factor-1 in centenarians: implications of IGF-1 as a rapid turnover protein.

BACKGROUND: It is well documented that serum insulin-like growth factor 1 (IGF-1) levels as well as growth hormone secretion decline with advancing age. Low levels of IGF-1 are shown to be associated with low activity of growth hormone, low lean mass, and high body fat mass; however, in the elderly, the relationship has not been confirmed. METHODS: We studied serum IGF-1 levels in 49 centenarians, who are at the ultimate stage of physiological senescence, and investigated the possible relationship between IGF-1 and body mass index, lipid parameters, nutritional indices, physical and cognitive function, and frequency of hip fracture. As nutritional indices, serum levels of albumin, prealbumin, transferrin, and retinol binding protein were measured. Cognitive function of the centenarians was assessed by clinical dementia rating. RESULTS: In the centenarians, the mean levels of IGF-1 were relatively low, indicating that there is an age-associated decline in IGF-1 even in the extremely old age. We demonstrated a strong association of IGF-1 with prealbumin and retinol binding protein (r2 = .192, .195, respectively); however, there was no association with albumin, transferrin, or body mass index. Interestingly, centenarians with lower IGF-1 levels had a higher prevalence of definitive dementia. CONCLUSIONS: These data suggest that serum IGF-1 levels in the centenarians appeared to reflect their short-term nutritional status as a rapid turnover protein. It is also suggested that low levels of serum IGF-1 may be involved in the progression of dementia in the oldest old.

Aged↗
PubMed2001

Herpes simplex mimicking herpes zoster in a child immunized with varicella vaccine.

A 5-year-old boy had zosteriform vesicular lesions 4 years after immunization with varicella vaccine. PCR analyses of DNA extracted from the crusts revealed herpes simplex virus type 1 infection. Virologic examinations should be performed before the vesicular lesion is attributed to the varicella-zoster virus vaccine strain.

Chickenpox Vaccine↗
PubMed2000

CDC6 interacts with c-Myc to inhibit E-box-dependent transcription by abrogating c-Myc/Max complex.

The c-myc oncogene product (c-Myc) is a transcription factor that dimerizes with Max and recognizes the E-box sequence. It plays key functions in cell proliferation, differentiation and apoptosis. It is generally thought that c-Myc transactivates genes encoding proteins essential to cell-cycle progression by binding to the E-boxes that control them. The functions of c-Myc are also thought to be modulated by its associated proteins, several of which have recently been identified. In this study, we found that c-Myc directly bound in vivo and in vitro to the N-terminal region of human CDC6, a component of the pre-replication complex, and that both co-localized in cell nuclei. CDC6 bound to the C-proximal region of c-Myc, thereby competing with Max on the E-box sequence and changing c-Myc/Max heterodimer to a Max/Max homodimer. In consequence, the E-box-dependent transcription activity of c-Myc was abrogated. These results suggest that, in addition to its DNA replication activity, CDC6 also has a role as a transcriptional suppressor of c-Myc.

Basic Helix-Loop-Helix Leucine Zipper Transcriptio↗
PubMed2000

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using an inorganic particle matrix for small molecule analysis

Fine metal or metal oxide powder as an alternative to conventional organic matrices in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) has been utilized successfully for lower molecular mass analytes, poly(ethylene glycol) 200 (PEG 200) and methyl stearate. Eleven kinds of particle, Al, Mn, Mo, Si, Sn, SnO2, TiO2, W, WO3, Zn and ZnO, were evaluated. The analyte was mixed with a metal or metal oxide powder (inorganic matrix) with particle diameter of tens of micrometers and liquid dispersant, followed by application to the sample target. Using a commercial MALDI-TOFMS instrument equipped with an internal 337 nm pulsed nitrogen laser, the analytes, PEG 200 and methyl stearate, were ionized as the alkali metal ion adducted molecules [M+Na]+ or [M+K]+ when the inorganic matrices Mn, Mo, Si, Sn, TiO2, W, WO3, Zn or ZnO were used. In the case of an Al matrix, PEG 200 was ionized as [M+K]+, whereas methyl stearate was ionized as [M+H]+ and [M+Al]+. These particles have potential as the matrix for MALDI. During our examination, however, only SnO2 particles did not ionize either PEG 200 or methyl stearate. Based on our protocol, when TiO2 powder was suspended with liquid paraffin, PEG 200 and methyl stearate gave their MALDI-TOF mass spectra with the lowest background noise and highest intensity. TiO2 powder seemed to be a broad potential matrix for low molecular mass polar or non-polar analytes. The results suggested that bulk particles caused rapid heating/vaporization processes and ionized analyte molecules under irradiation with a pulsed UV laser. The present method can be readily applied to obtain the low background noise MALDI-TOF mass spectra of small-sized compounds.

Journal Article↗
PubMed2000

Sequence information of peptides and proteins with in-source decay in matrix assisted laser desorption/ionization-time of flight-mass spectrometry.

In-source decay coupled with matrix assisted laser desorption/ionization-mass spectrometry, which is a mass spectrometric degradation method for the sequencing of peptides and proteins, has been applied to several different polypeptides and proteins. The influence of the nature of the constituent amino acids on positively charged product ions is described. Relatively small molecular mass peptides produced c-, b-, and/or a-series ions usable for C-terminal sequencing as well as y- and/or z-series ions usable for N-terminal sequencing. The formation of the C-terminal sequencing ions (c, b and a) and the N-terminal sequencing ions (y and z) was strongly dependent on the location(s) of basic arginine and lysine residues. The presence of the arginine and/or lysine residues at the N-terminal region was one-sided in the formation of c-, b-, and/or a-series ions, while the presence of those at the C-terminal region was favorable for the formation of y- and z-series ions. In-source decay experiments of intact proteins, apomyoglobin and two viral coat proteins, led to large amounts of c-series ions and small amounts of y-series ions, which reflected internal sequences.

Amino Acid Sequence↗
PubMed2000

Study on fragmentation behavior of 5/7/6-type taxoids by tandem mass spectrometry.

The mass spectrometric behaviors of seven compounds, namely four 4beta(20),5-oxetane 5/7/6-type taxoids (i.e. taxayuntin A, taxayuntin B, taxayuntin and taxayuntin C) and three 4(20)-methylene 5/7/6-type taxoids (i.e. brevifoliol, taxchinin A and 7-acetyl-10-deacetyl-7-debenzoylbrevifoliol) have been investigated by the positive ion FAB-MS/MS technique. The fragmentation has been correlated with the types and positions of substituents of these compounds. It has been found that with the OH group at the C-10 position, taxayuntin A, taxayuntin B and 7-acetyl-10-deacetyl-7-debenzoylbrevifoliol are dominated by the loss of H2O, while with the BzO group at the C-10 position, taxayuntin, taxayuntin C, brevifoliol and taxchinin A preferentially eliminate the BzO group. In addition, C-2 is an active site, and neutral loss from the C-2 position readily occurs. The four 4beta(20),5-oxetane 5/7/6-type taxoids produce the terminal product ion with a stable conjugated system at m/z 311, while the 4(20)-methylene 5/7/6-type taxoids brevifoliol and 7-acetyl-10-deacetyl-7-debenzoylbrevifoliol produce this ion at m/z 237, and taxchinin A at m/z 253. Interestingly, characteristic fragment ions involving the loss of a 118 u group were observed for taxayuntin, and a possible fragmentation mechanism is given. The major fragmentation pathways and mechanisms of ion formation for the compounds are proposed on the basis of CID spectra and accurate mass measurements. The results of this paper will be helpful for structural analysis of analogs.

Plant Extracts↗
PubMed2000

Clinical applications of serum placental protein 14 (PP14) measurement in the IVF-ET cycle.

OBJECTIVE: Placental protein 14 (PP14) is known to be one of the endometrial proteins that reflect endometrial functioning throughout the menstrual cycle. In this study, we examined PP14 as a marker for human endometrial receptivity in order to predict the outcome of in vitro fertilization and the embryo-transfer (IVF-ET) cycle. PATIENTS AND METHODS: The subjects were 72 women who had 96 IVF-ET cycles and who were examined at Tokyo Medical University Hospital during the period of January 1998 to June 1998 because of mechanical or unexplained infertility for a duration of at least 2 years. Serum samples were collected from all patients during treatment cycles, and serum PP14 concentrations were measured by a newly established enzyme-linked immunosorbent assay (ELISA). RESULTS: In the pregnant group, serum PP14 concentrations were markedly increased after ET, and a significant difference between the pregnant group and the nonpregnant group was observed 8 days following ET (p < 0.01). PP14 concentrations were higher in patients with endometria that exhibited homogenous patterns and that were more than 7 mm thicker than in other patients, as determined by ultrasound on the day of oocyte collection (p < 0.005). The pregnancy rates of patients with homogeneous patterns were lower than those of patients showing a trilaminar pattern. No pregnancies were observed when serum PP14 concentrations were greater than 6.85 U/l on the day of oocyte collection. CONCLUSION: PP14 might be a useful marker for human endometrial receptivity to predict the outcome of IVF-ET cycles.

Adult↗
PubMed2000

[A neonatal varicella case confirmed early to be infected with varicella-zoster virus using PCR analysis].

A neonatal varicella case confirmed early to be infected with varicella-zoster virus (VZV) using PCR analysis was reported. The mother developed an eruption on the following day the patient's birth and was diagnosed as varicella at 3 day of age. The neonate received immunoglobulin and acyclovir (17.5 mg x twice). She was speculated to develop varicella on the 5 to 10 day of age. Eruptions were noted, however, on the 13 day of age, although she was confirmed to be infected with VZV using PCR on the 6 day of age, and her symptoms were much milder than that foreseen. Delay of development and mildness of her symptoms may be attributed to immunoglobulin and acyclovir given on the 3 day of age. PCR method was very useful in determining early that she was infected with VZV.

Chickenpox↗
PubMed2000

Rapid genotyping of varicella-zoster virus vaccine and wild-type strains with fluorophore-labeled hybridization probes.

We developed a single-tube rapid method for the detection and differentiation of varicella-zoster virus (VZV) vaccine and wild-type strains that combines rapid-cycle PCR with wild-type-specific fluorescent probe melting profiles for product genotyping. A region including the polymorphic site in VZV open reading frame (ORF) 62 was amplified in the presence of two fluorescence-labeled hybridization probes. During the annealing step of the thermal cycling, both probes bound to their complementary sequences in the amplicon, resulting in resonance energy transfer, thus providing real-time fluorescence monitoring of PCR. Continuous acquisition of fluorescence data during a melting curve analysis at the completion of PCR revealed that loss of fluorescence occurred in a strain-specific manner as the detection probe, which was fully complementary to the wild-type VZV ORF 62 region, melted off the template. Use of this method allowed genotyping of samples within minutes after the completion of PCR, eliminating the need for post-PCR sample manipulation. In addition to reducing the time required to produce a result, this method substantially reduces the risk of contamination of the final product as well as the risk of sample tracking errors. The genotypes of 79 VZV-positive samples determined by this fluorescent resonance energy transfer (FRET) method were identical to the genotypes obtained by conventional PCR and restriction fragment length polymorphism analysis. The genotyping of VZV strains by the FRET method is a rapid and reliable method that is suitable for typing and that is also practical for use for the processing of large numbers of specimens.

Base Sequence↗
PubMed2000

Improved identification and differentiation of varicella-zoster virus (VZV) wild-type strains and an attenuated varicella vaccine strain using a VZV open reading frame 62-based PCR.

A new method was developed to identify and differentiate varicella-zoster virus (VZV) wild-type strains from the attenuated varicella Oka vaccine strain. The PCR technique was used to amplify a VZV open reading frame (ORF) 62 region. A single specific amplicon of 268 bp was obtained from 71 VZV clinical isolates and several laboratory strains. Subsequent digestion of the VZV ORF 62 amplicons with SmaI enabled accurate strain differentiation (three SmaI sites were present in amplicons of vaccine strain VZV, compared with two enzyme cleavage sites for all other VZV strains tested). This method accurately differentiated the Oka vaccine strain from wild-type VZV strains circulating in countries representing all six populated continents. Moreover, the assay more reliably distinguished wild-type Japanese strains from the vaccine strain than did previously described methods.

Chickenpox↗
PubMed2000

Pulmonary edema after cardioversion for paroxysmal atrial flutter: left ventricular diastolic dysfunction induced by direct current shock.

This report describes a patient with the pulmonary edema after cardioversion for paroxysmal atrial flutter without organic heart disease. A 68-year-old man was admitted to hospital for paroxysmal atrial flutter. Antiarrhythmic agents were not effective, and direct current cardioversion was performed on the 4th hospital day. Three hours after cardioversion, the patient complained of dyspnea, and a chest X-ray showed pulmonary edema. He responded to oxygen, intravenous furosemide and drip infusion of nitroglycerine. During tapering of the medication, his condition remained stable. The patient was discharged on the 7th day after admission. Echocardiographic findings indicated that transient left ventricular diastolic dysfunction due to direct current shock was the most likely cause of the lung edema.

Aged↗
PubMed2000

Transfer of SV40 temperature-sensitive early gene into human epidermal keratinocytes by the recombinant adenovirus vector.

We constructed a recombinant adenovirus vector that contained the origin-defective SV40 early gene, coding temperature-sensitive T antigen. This vector transferred the SV40 early gene into human epidermal keratinocytes with high efficiency. T antigen conferred the ability of keratinocytes to grow with limited differentiation in the presence of serum and high calcium concentration at the permissive temperature (34 degrees C), although normal keratinocytes were induced to differentiate and stop growing under the same conditions. The serum/Ca++-resistant cells did not proliferate at the nonpermissive temperature (40 degrees C), indicating that they depended on T antigen for their proliferation. The temperature-sensitive T antigen dissociated from the tumor suppressor gene products, p53, at 40 degrees C. The serum/Ca++-resistant cells still had the ability to proceed to terminal differentiation when injected into SCID mice as cultured keratinocytes. However, they did not form an apparent basal layer. This indicated that the tissue remodeling process in the serum/Ca++-resistant keratinocytes was abnormal. All of these epidermoid cysts disappeared within 8 wk and no tumor developed for 6 mo. We consider that deltaE1/SVtsT is a useful tool to examine multistep carcinogenesis of human epithelial cells in vitro.

Adenoviridae↗
PubMed2000

Novel assay for measuring serum conjugated bilirubin and its clinical relevance.

We have developed a new enzymatic assay for the determination of conjugated bilirubin (Bc) using stable liquid reagents. In this assay, only Bc is selectively oxidized by bilirubin oxidase at pH 5. 0 in the presence of nitrilotris (methylenephosphonic acid) trisodium salt, ethylenediaminetetraacetic acid disodium manganese (II) salt, and 4-hydroxy-2,2,6,6,-tetramethylpiperidine 1-oxyl. Bc is quantitatively determined from a decrease in the absorbance at 450 nm caused by Bc oxidization. The reagent solutions of the assay were developed so that they could be stably stored for one year together with bilirubin oxidase, in order to eliminate the need to prepare working solutions every time they are required. The assay has good reactivity, differentiability, measurability, and precision. Neither ascorbic acid nor hemoglobin interfered with the measurement. Bc values determined by the assay reflected more clearly the pathophysiological condition of hepatobiliary disease patients with jaundice than the values of total bilirubin or direct bilirubin determined by conventional methods. From these observations, we concluded that this Bc assay is valuable for the evaluation of jaundice.

Bilirubin↗
PubMed2000

[Toxoplasma pericarditis without immunosuppressant disorder detected by polymerase chain reaction of pericardial fluid: a case report].

There have been several case reports, a total of 22 up to the present, of toxoplasma pericarditis. Out of them, in only a few cases the diagnosis was properly made with a proof of the microscopic presence of Toxoplasma gondii. This is the first report of toxoplasma pericarditis in which the presence of Toxoplasma gondii was detected by polymerase chain reaction of pericardial effusion. In addition, the previous reports will be reviewed, and compared to this present case. A 29-year-old woman, without immunosuppressant disorder, suffering from fever and orthopnea was admitted to our hospital. Blood chemistry findings indicated mild liver dysfunction and inflammation. Chest radiography showed cardiac enlargement. Electrocardiography showed sinus tachycardia and ST elevation. Echocardiography revealed a massive pericardial effusion. Pericardiocentesis demonstrated 638 ml of bloody fluid. Cytologic study of the fluid was class II for malignancy, and polymerase chain reaction to tuberculosis was negative. However, a high titer of the anti-toxoplasma antibody of 1: 20,480 (passive hemagglutination) indicated pericarditis caused by Toxoplasma gondii. Subsequently, Toxoplasma gondii was identified in the pericardial effusion by polymerase chain reaction. Clinical symptoms improved after pericardiocentesis, but 2 months later pericarditis recurred. Treatment was started with 800 mg acetylspiramycin daily but failed to improve the symptoms. Because of the development of pleuritis, treatment was changed to sulfadoxine 1,000 mg/pyrimethamine 50 mg. After the treatment with them, her symptoms improved. Only 22 cases of toxoplasma pericarditis have been reported worldwide and 15 of those cases were without immunosuppressant disorder. The usual symptoms at the onset of pericarditis without immunosuppressant disorder are fever, dyspnea and chest pain. Seven patients developed cardiac tamponade. Pericardiocentesis was performed in 8 cases and the pericardial fluid was hemorrhagic in 6. Pericardial thickening was detected in 5 cases. The diagnosis of toxoplasma infection is very difficult, because asymptomatic infection of Toxoplasma gondii is very common. Pericarditis is a disease difficult to confirm the etiology. Detection of Toxoplasma gondii in pericardial effusion by the polymerase chain reaction is very useful for its diagnosis.

Adult↗
PubMed2000

[A pilot trial of high dose CEP (cyclophosphamide, epirubicin, cis-platinum) therapy in patients with advanced and recurrent ovarian cancer].

We evaluated the feasibility of high-dose CEP (cyclophosphamide 750 mg/m2, epirubicin 90 mg/m2, cis-platinum 70 mg/m2) therapy, with granulocyte colony-stimulating factor support every 21 days, in 18 patients with advanced and recurrent ovarian cancer. Ten patients (56%) received 6 cycles of this regimen as planned. Toxicities more than grade 3/4 on' the WHO scale of neutropenia and thrombocytopenia were observed in all cases. Nausea, vomiting, mucositis, malaise, alopecia, hepatotoxicity, and fever were common adverse effects. The average relative dose intensity of cyclophosphamide, epirubicin, cis-platinum was 0.77, 0.77, 0.79 respectively, and each RDI decreased in the last two cycles. These data suggest that this regimen could be performed safely with careful consideration on hepatotoxicity and thrombocytopenia.

Adult↗