Biomedical subjects

T Kojima

Publications and source records attributed to T Kojima.

At least 145 records · Page 8Linked to original sources

PubMed2000

Ryudocan expression by luteinized granulosa cells is associated with the process of follicle atresia.

OBJECTIVE: To evaluate the presence of ryudocan in follicular fluid (FF) and its possible correlation with FF E(2) and P, and to study the levels of ryudocan in granulosa-lutein cells stimulated with hCG. DESIGN: Controlled clinical study and in vitro experiment. SETTING: University teaching hospital. PATIENT(S): One hundred seven patients undergoing IVF. INTERVENTION(S): The FF and granulosa-lutein cells were aspirated from follicles 34 hours after an ovulatory gonadotropin bolus. MAIN OUTCOME MEASURE(S): FF ryudocan, E(2), and P levels as well as hCG-mediated induction of ryudocan. RESULT(S): Ryudocan was abundant in the FF; the concentration of ryudocan in human FF was estimated to be 305.5 +/- 200.8 ng/mL (mean +/- SD). Atretic follicles had higher concentrations of ryudocan (559.1 +/- 156.5 ng/mL). FF ryudocan levels were inversely correlated with FF E(2) (r = -0.5023) and P concentrations (r = -0.4459). A detectable amount of ryudocan was found in pooled granulosa-lutein cells. Ryudocan production was augmented by surge levels of hCG. CONCLUSION(S): Ryudocan is expressed in luteinized granulosa cells in vitro. The higher concentrations of ryudocan in FF of atretic follicles suggest an involvement of ryudocan in the process of atresia.

Adult↗

PubMed2000

Hemoclipping for postpolypectomy and postbiopsy colonic bleeding.

BACKGROUND: Obtaining colonoscopic biopsies and polypectomy can result in hemorrhage. The most effective management of this complication has not been determined. The objective of this study was to evaluate the endoscopic hemoclip in postprocedural colonic bleeding. METHODS: Among 9555 consecutive colonoscopies, cases of postprocedural colonic bleeding (postpolypectomy and postbiopsy) requiring treatment were retrospectively reviewed. Endoscopic hemoclipping was initially attempted in each case; the rate of hemostasis after hemoclipping, use of additional hemostatic methods, and clinical outcome (need for transfusion/hospitalization) were analyzed. RESULTS: There were 72 cases of bleeding in which treatment was required (45 immediate postpolypectomy, 18 delayed postpolypectomy and 9 postbiopsy). Endoscopic hemostasis was achieved in all cases of immediate postpolypectomy and postbiopsy bleeding and in all but one of the cases with delayed postpolypectomy bleeding. A detachable snare was used in addition to hemoclips in 3 cases of delayed postpolypectomy bleeding. There were no episodes of recurrent bleeding, deaths or need for surgery related to bleeding. CONCLUSION: Early endoscopic management of postprocedural bleeding by hemoclipping provides hemostasis in the great majority of cases.

Biopsy↗

PubMed2000

Detailed characterization of an anti-factor IX monoclonal antibody that neutralizes the prolonged ox brain prothrombin time of hemophilia B(M) by synthetic peptides.

In a previous study, we prepared a monoclonal antibody (MoAb) to coagulation factor IX (FIX), designated 65-10, which interfered with the activation of FIX by the activated factor XI/Ca(2+) and neutralized the prolonged ox brain prothrombin time of hemophilia B(M) [11,12]. The location of the epitope on the FIX for 65-10 MoAb is (168) Ile-Thr-Gln-Ser-Thr-Gln-Ser-Phe-Asn-Asp-Phe-Thr-Arg-Val-Val(182) [21]. In this paper, we studied in more detail an epitope on FIX using the systematic substitution of different amino acids at each residue of the epitope peptides and the influence of the epitope peptide on the prolonged ox brain prothrombin time of the hemophilia B(M) plasma of 65-10 MoAb. In the replacement set of amino acids, peptides showing low or no reactivity to 65-10 were (175)Phe --> Asp, Glu, Gly, Lys, Arg, Thr, Val, (176)Asn --> Asp, Glu, Phe, Ile, Lys, Leu, Pro, Val, Tyr, (177)Asp --> Cys, Glu, Phe, Ile, Lys, Leu, Met, Pro, Gln, Arg, Ser, Thr, Val, Trp, Tyr, and (178) Phe --> Pro. These results imply that a hydrophobic molecule of (175) Phe, a hydrophilic molecule of (176)Asn, and a negative charge molecule of (177)Asp were important to the epitope. The 65-10 MoAb antibody neutralized the prolonged ox brain prothrombin time of hemophilia B(M) Nagoya 2 ((180)Arg -->Trp) and Kashihara ((181)Val --> Phe) as well as B(M) Kiryu ((313)Val --> Asp) and Niigata ((390)Ala --> Val). This reaction was inhibited by preincubation with a (168) Ile-Thr-Gln-Ser-Thr-Gln-Ser-Phe-Asn-Asp-Phe-Thr-Arg-Val-Val(182) peptide conjugated with bovine serum albumin (BSA). 65-10 MoAb that has been useful in detailing epitopes will be useful for qualitative analysis of hemophilia B(M).

Amino Acid Sequence↗

PubMed2000

Traumatic avulsion fracture of the occipital condyles and clivus: a case report.

A 25-year-old male was found dead on a river bank. Wounds and injuries were found on the corpse, and a bloodstain was found on the face from blood discharged from the oral and nasal cavities. Since the man was considered the victim of a traffic accident, a forensic autopsy was carried out. At the time of autopsy, severe bruises and wounds were found on the occiput, the nape and the dorsal side of the lower extremities. There was a fracture line in the bilateral occipital condyles through the lower part of the clivus and the head was unstable in relation to the neck. The medulla oblongata was severed near the fracture site and the basilar artery was also torn at the branching end of the posterior cerebral arteries. The fracture of the occipital condyles and clivus was considered to be avulsed due to hyperflexion of the neck joint by a blunt impact onto the occiput. Anterior traction of the skull following the fracture was supposed to have accompanied the injuries of the medulla oblongata and the basilar artery. In this autopsy case, the authors observed an unusual type of fracture in the posterior cranial fossa.

Journal Article↗

PubMed2000

Sensitive determination of mianserin and setiptiline in body fluids by gas chromatography with surface ionization detection (GC-SID).

Tetracyclic antidepressants, mianserin and setiptiline, in human body fluids have been found measurable with high sensitivity by gas chromatography (GC) with surface ionization detection (SID). The compounds in human whole blood or urine samples were extracted by solid-phase extraction using Bond Elut C(18) cartridges. The recoveries of both compounds from the body fluids were above 85%. For quantitation of mianserin, 25 ng of setiptiline was used as internal standard; and for quantitation of setiptiline, vice versa. The calibration curves for spiked whole blood or urine samples were linear in the range of 1.25-50 ng/ml. The detection limit of mianserin and setiptiline was about 1 ng/ml, which is comparable to those obtained by the previous GC-mass spectrometry methods. Our method seems very useful for determination of mianserin and setiptiline in forensic and clinical toxicology, because of high sensitivity, low background impurities and easy handling of the GC instrument.

Journal Article↗

PubMed2000

Sensitive determination of pentazocine in human tissues by high-performance liquid chromatography.

The authors developed a simple, reliable and sensitive method for the determination of pentazocine in human solid tissues using high-performance liquid chromatography, combined with a three-step liquid-liquid extraction procedure. Levallorphan tartrate served as the internal standard. The extract was evaporated to dryness and dissolved in the mobile phase of acetonitrile/10 mM phosphate buffer (pH 4.0). The eluent was pumped at a flow rate of 0.4 ml/min through a Spherisorb Ph (2.1 mm I.D. x 150 mm) column. A fluorescence detector with excitation at 247 nm and emission at 320 nm was used. The lower limit of detection was about 0.5 ng/g. The calibration curve was linear over the concentration ranges from 1 to 500 ng/g in each tissue examined and could be determined up to at least 10.0 microg/g by means of reduction of injected volumes. Using this method, the concentrations of pentazocine could be determined in the tissues of an autopsied individual for toxicological evaluation.

Journal Article↗

PubMed2000

A short peptide derived from the antisense homology box of Fas ligand induces apoptosis in anti-Fas antibody-insensitive human ovarian cancer cells.

We found that a short synthetic peptide corresponding to the "antisense homology box" of Fas ligand induced apoptotic cell death of Fas-expressing human ovarian cancer cell lines. The peptide was deduced from residues 256-265 of human Fas ligand, based on the hypothesis that it should contain a specific binding site to the corresponding Fas. Interestingly, the ovarian cancer cell line NOS4, which was sensitive to anti-Fas antibody induced apoptosis, was not affected by the peptide, whereas another cell line, SKOV-3, which was insensitive to anti-Fas antibody, was killed by the peptide. Thus, this short peptide was shown to have a unique activity to induce apoptosis in human ovarian cancer cells in a manner different from anti-Fas antibody.

Antibodies, Monoclonal↗

PubMed2000

Myopericarditis caused by cyclophosphamide used to mobilize peripheral blood stem cells in a myeloma patient with renal failure.

Cyclophosphamide (CPA) is widely used for peripheral blood stem cell mobilization, and a dose adjustment of CPA in the presence of renal failure has not been suggested. However, we describe a myeloma patient with renal failure (serum creatinine 4.2 mg/dl, creatinine clearance 11.2 ml/min) receiving CPA 2 g/m2 for 2 days, who developed unexpectedly severe toxicity, including myopericarditis and prolonged myelosuppression. The serial serum concentrations of CPA metabolites were persistently much higher than those in a myeloma patient with normal renal function. We consider, therefore, that the dose of CPA should be reduced in the presence of severe renal failure when used as high-dose therapy or to mobilize peripheral blood stem cells.

Adult↗

PubMed2000

Plat-E: an efficient and stable system for transient packaging of retroviruses.

A potent retrovirus packaging cell line named Platinum-E (Plat-E) was generated based on the 293T cell line. Plat-E is superior to existing packaging cell lines regarding efficiency, stability and safety. The novel packaging constructs utilized in establishment of Plat-E ensure high and stable expression of viral structural proteins. Conventional packaging constructs made use of the promoter of MuLV-LTR for expression of viral structural genes gag-pol and env, while our packaging constructs utilized the EF1alpha promoter, which is 100-fold more potent than the MuLV-LTR in 293T cells in combination with the Kozak's consensus sequence upstream of the initiation codon resulting in high expression of virus structural proteins in Plat-E cells. To maintain the high titers of retroviruses under drug selection pressure, we inserted the IRES (internal ribosome entry site) sequence between the gene encoding gag-pol or env, and the gene encoding a selectable marker in the packaging constructs. Plat-E cells can stably produce retroviruses with an average titer of 1 x 107/ml for at least 4 months. In addition, as we used only the coding sequences of viral structural genes to avoid inclusion of unnecessary retrovirus sequences in the packaging constructs, the probability of generating the replication competent retroviruses (RCR) by recombination can virtually be ruled out.

Cell Line↗

PubMed2000

A case of purpura fulminans is caused by homozygous delta8857 mutation (protein C-nagoya) and successfully treated with activated protein C concentrate.

We report a Japanese patient who developed purpura fulminans and disseminated intravascular coagulation (DIC) shortly after birth. The patient was diagnosed to be homozygous for protein C deficiency and was treated with an activated protein C (APC) concentrate. Intravenous infusions of APC markedly improved the necrotic skin lesions and the anticoagulation by APC enabled successful DIC control. The identified mutation (Delta8857) results in impaired intracellular transport and protein maturation and would be the cause of the complete protein C deficiency. This is the seventh case of the mutation that has been exclusively reported in Japan, but is the first report of a homozygous case. Our findings propose new therapeutic and diagnostic tools for the management of this fatal thrombotic disease.

Disseminated Intravascular Coagulation↗

PubMed2000

Age at onset of schizophrenia: gender differences and influence of temporal socioeconomic change.

This study was undertaken to examine whether males develop schizophrenia at a younger age than females, and whether temporal socioeconomic change affects the age at onset of schizophrenia. The subjects were 848 ICD-9 schizophrenics who were admitted to Nihon University Hospital, Tokyo, Japan, during the period of 1955-64 (n = 468 (214 males and 254 females), group A) or during the period of 1982-91 (n = 380 (220 males and 160 females). group B). Schizophrenic males showed an earlier age at onset than schizophrenic females. However, the mean age at onset of schizophrenia did not differ significantly between group A and group B. These results indicate that the gender difference in age at onset of schizophrenia has not been influenced by temporal socioeconomic change.

Adolescent↗

PubMed2000

Two nap sleep test: an easy objective sleepiness test.

The two nap sleep test (TNST) was developed and its usefulness for detecting sleepiness in long-distance drivers has been reported. This study's authors attempted to apply the TNST as a clinical test of sleepiness. A normal control group (n = 29), an obstructive sleep apnea syndrome (OSAS) group (n = 9), and another sleep disorder group (n = 6) participated. As a result of polysomnography, the sleep latency and sleep time did not differ among the groups. In contrast, the frequency of micro-arousal and movement arousal was significantly higher in the OSAS group than in the other groups. The TNST is thought to be useful for evaluating disturbance of sleep maintenance.

Adult↗

PubMed2000

Molecular biology of ryudocan, an endothelial heparan sulfate proteoglycan.

Ryudocan is a type I integral membrane heparan sulfate proteoglycan, which was originally cloned from rat microvascular endothelial cells. We have cloned the cDNA of rat ryudocan. The deduced amino acids of ryudocan has homologous transmembrane and intracellular domains with syndecan but very distinct extracellular regions. We also cloned the human ryudocan cDNA, of which the gene localizes on the chromosome 20q12. To better understand the regulation of ryudocan expression, we have determined the structural organization of the human ryudocan gene. The human ryudocan gene extends approximately 24 kb and is divided into five exons that appear conserved in syndecan family members. The 5'-flanking sequences of the human ryudocan gene contain a variety of potential binding sites for transcription factors and are capable of functioning as a promoter. We purified human ryudocan and evaluated its interactions with several extracellular ligands. It was found that basic fibroblast growth factor (bFGF), midkine, and tissue factor pathway inhibitor exhibited significant ryudocan bindings. Heparitinase, but not chondroitin ABC lyase treatment, destroyed those ryudocan bindings; thus, the heparan sulfate chains of ryudocan appear to be responsible for those bindings. Immunohistochemical analysis revealed that ryudocan is expressed in peripheral nerve tissues, fibrous connective tissues, and placental trophoblasts. These findings suggest that ryudocan may possess multiple biologic functions, such as bFGF modulation, neurite growth promotion, and anticoagulation, via heparan sulfate-binding effectors in the cellular microenvironment.

Amino Acid Sequence↗

PubMed2000

Colonoscopic polypectomy with cutting current: is it safe?

BACKGROUND: Coagulation and blended electrosurgical current are currently recommended for colonoscopic polypectomy, whereas pure cut current is believed to be associated with a higher risk of bleeding. However, the outcome of polypectomy performed with a cut current has not been evaluated in a large case series. Our objective was to study the incidence and nature of complications when polypectomy is performed with a pure cut current. METHODS: Among 9555 colonoscopic examinations, polypectomy cases were retrospectively reviewed for complications. The electrosurgical current applied was always the cutting waveform. RESULTS: Electrosurgical polypectomy using pure cut current was performed to remove 4735 lesions. Hemoclips were applied to the excision site after polypectomy to prevent bleeding in 12% of the cases. Hemorrhage occurred in 1.1% of the polypectomies (3.1% of patients). The incidence of bleeding with the different methods was snare polypectomy 0.9%, endoscopic mucosal resection 1.6%, "hot" biopsy 0.4%, and piecemeal polypectomy 7.3%. Bleeding was immediate in 66.1% of episodes and delayed in 33.9%. Patients with delayed postpolypectomy bleeding were significantly younger than those with immediate bleeding (50.5 and 64.7 years, respectively, p < 0.001). There was 1 case of transmural burn, but no perforations. CONCLUSION: Polypectomy can be performed with pure cut current with a bleeding rate comparable to that seen with the use of coagulation or blended current, provided that hemoclip placement can be used readily. Expertise in hemoclip placement is advisable if this method of polypectomy is to be used.

Adult↗

PubMed2000

Use of an ultrahigh-speed laser scanner for constructing three-dimensional shapes of dentition and occlusion.

STATEMENT OF PROBLEM: Acquisition of the 3-dimensional shape of dental casts is useful for quantitative evaluation of the diagnosis and treatment of occlusion. PURPOSE: This study demonstrated the acquisition of data through the use of an ultrahigh-speed laser scanner and an originally developed goniometer, the use of these tools to measure the entire 3-dimensional shape of the dental cast from multiple directions, and the connection of the data measurements to reconstruct the cast's occlusion with the use of a computer. MATERIAL AND METHODS: A commercially available apparatus that emits a line laser and completes 1 scan in only 0.6 seconds was used. To compensate for the unmeasured region, the cast was measured from 4 directions on the original goniometer, and the connection of data to obtain the entire image was carried out. Further, the reconstruction of the occlusion between the upper and lower casts was attempted by transferring the upper cast data to the lower cast. RESULTS: By the data connection, the entire shape of the upper and lower casts was constructed, and the characteristic structure was reproduced. The data connections were satisfactory for the flat surfaces but less accurate for the inclined surfaces. Reconstruction of the occlusion between the upper and lower casts was accomplished. It was then possible to visualize the occlusion from arbitrary directions and sections with computer graphics. CONCLUSION: The construction of the entire 3-dimensional shape of a dental cast and the reconstruction of the occlusion were accomplished using an ultrahigh-speed measurement system and original goniometer. These results will be useful for clinical applications such as computerized diagnoses and treatment of occlusion, and for the replacement of the stone casts in the dental office by computerized data.

Calibration↗

PubMed2000

Mitogenic activity of gelatin to murine spleen cells.

We reported previously that gelatin stimulates the growth of spleen cells in vitro. Tritium thymidine (3H-TdR) uptake into phytohemagglutinin (PHA)-stimulated spleen cells as well as intact spleen cells was augmented by gelatin. These findings suggest that gelatin serves as a mitogen for lymphoid cells. In this study, the target of action of gelatin was investigated. Tritium thymidine uptake into T cell-rich fraction was enhanced by incubation with 7.5 mg/ml of gelatin for 48 hours. The level of 3H-TdR uptake into B cell-rich fraction was not definitely increased by gelatin. Flow cytometric analysis confirmed these findings. Namely, it showed that treatment of spleen cells with 7.5 mg/ml gelatin increased a ratio of CD3-positive cells and decreased that of CD19-positive cells. Tritium thymidine uptake into natural killer cell-rich fraction was augmented by gelatin in a similar fashion to T cell-rich fraction. Tritium thymidine uptake into macrophages was very low and not affected by gelatin. Tritium thymidine uptake into macrophage-precursors was very low but was enhanced by gelatin. These findings suggest that gelatin could be used as an agent of cancer biotherapy.

Animals↗

PubMed2000

Effect of red blood cells on the antitumor activity of oxycellulose.

The antitumor activity of oxycellulose to MH134 tumor cells, evaluated with microscopic viable cell count, was suppressed by murine red blood cells (MRBCs) in a dose-dependent manner. The antitumor activity of oxycellulose was suppressed by MRBCs also when evaluated with 3H-TdR uptake. However, that of mitomycin C or 5-fluorouracil was not suppressed by MRBCs. On the other hand, the antitumor activity of oxycellulose was suppressed by MRBCs also when evaluated with 51Cr release assay. At that time, the antitumor activity of cisplatin to MH134 tumor cells were not suppressed by MRBCs. The antitumor activity of oxycellulose to MH134 tumor cells was suppressed by the membrane or the cytosol fraction of the lysate of MRBCs as well as intact MRBCs. When heated at 56 degrees C for 30 min, MRBCs were unable to suppress the activity of oxycellulose. It was examined whether or not proteins related to MRBCs (hemoglobin, catalase, superoxide dismutase or taurine) suppressed the activity of oxycellulose. They did not suppress the activity of oxycellulose.

Animals↗

PubMed2000

Effect of hemostatics used during operations for digestive organ on cancer cells present in the peritoneal cavity.

We investigated effects of hemostatics used during operations for digestive organ on cancer cells present in the peritoneal cavity using BALB/c mice inoculated with Meth A tumor cells (fibrosarcoma) intraperitoneally (i.p.) and C3H/He mice inoculated with MH134 tumor cell (hepatic cell carcinoma) i.p. Microfibrillar collagen hemostat (Avitene) or fibrinogen preparation (Beriplast P) did not affect survivals of those tumor-bearing mice. Gelatin sponge (Spongel)prolonged survivals of MH134 tumor-bearing mice. Liquid form gelatin used instead of Spongel displayed in vitro antitumor effect on MH134 tumor cells at the concentration of 15 mg/ml. Radioactive sodium chromate-labeled MH134 and Meth A tumor cells were not lysed when they were incubated with 15 mg/ml of liquid form gelatin for 24 hours. On the other hand, the tritium thymidine (3H-TdR) uptake by MH134 or RL male 1 tumor cells was suppressed when they were incubated with 15 mg/ml of liquid form gelatin for 24 hours. Proliferation of Meth A tumor cells were not affected by the treatment. Effect of liquid form gelatin on phytohemagglutinin (PHA)-stimulated spleen cells as a benign counter-part of RL male 1 tumor cells (T cell lymphoma) was examined. Liquid form gelatin (15 mg/ml) did not suppress 3H-TdR uptake by PHA-stimulated spleen cells.

Animals↗