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Biomedical subjects

M Kamada

Publications and source records attributed to M Kamada.

At least 127 records · Page 7Linked to original sources
PubMed1996

Quantification of the CD55 and CD59, membrane inhibitors of complement on HIV-1 particles as a function of complement-mediated virolysis.

Previous studies have demonstrated that the murine monoclonal antibody (MoAb) NM-01 activates the human complement classical pathway resulting in lysis of human immunodeficiency virus (HIV). The present study was performed to determine the availability of the V3-loop of gp120 relative to the complement regulatory proteins, CD55 (DAF) and CD59 (HRF20) molecules on HIV. The results demonstrate that CD55 and CD59 exist on HIV virions, along with gp120 molecules. These findings suggest that activation of human complement on free viral particles is induced by MoAb NM-01 and that this occurs regardless of the presence of CD55 and CD59 molecules. The destruction of viral particles was demonstrated by a decrease in infectivity. The involvement of human complement in this process was confirmed with an immunoelectron microscopy technique by the presence of a human C9 to prove membrane attack complex (MAC). The results indicate that NM-01 can induce complement activation because of the ratios of CD55 and CD59 to gp120 molecules on HIV virions. The availability of the gp120 V3 domain on the virion is sufficient for binding of NM-01 and thereby the formation of MAC that results in virolysis.

Antibodies, Monoclonal↗
PubMed1995

Comparative studies of human recombinant 74- and 54-kDa L-histidine decarboxylases.

We have expressed and characterized human recombinant 74-kDa (rHDC74) and 54-kDa (rHDC54) L-histidine decarboxylases (HDCs) in Sf9 cells. By immunoblot analysis, rHDC74 and rHDC54 were shown to be localized predominantly in the particulate and soluble fractions, respectively. rHDC74 exhibited histamine-synthesizing activity equivalent to that of rHDC54. The existence of 74- and 54-kDa HDCs was also confirmed in the particulate and supernatant fractions of the cell lysate, respectively, from the human basophilic leukemia cell line KU-812-F. The ratio of HDC activity to immunoreactivity was similar for the two forms of the enzyme. The specific activity of purified rHDC54 (1.12 mumol/mg/min) was comparable to those of HDCs from other mammalian tissues or cells. The purified rHDC54 was eluted as a monomer form from a Superdex-200 column; the molecular mass of the enzyme was approximately 54 kDa on SDS-polyacrylamide gel electrophoresis without 2-mercaptoethanol. The HDC activity of rHDC54 significantly decreased on dialysis against buffer without pyridoxal 5'-phosphate; addition of pyridoxal 5'-phosphate to the dialysate readily increased in the enzyme activity to the original activity. Taken together, these results suggest that human HDC functions as both 74- and 54-kDa forms having equivalent HDC activity, which are localized in the particulate and soluble fractions, respectively, and that the latter form exhibits its activity as a monomer form.

Animals↗
PubMed1995

Detection of equine arteritis virus (EAV) by polymerase chain reaction (PCR) and differentiation of EAV strains by restriction enzyme analysis of PCR products.

A polymerase chain reaction (PCR) based assay capable of detecting and differentiating seven strains of equine arteritis virus (EAV) from around the world was developed. The primers for the PCR were chosen from the ORF6 gene encoding the unglycosylated membrane protein (M). Viral RNA from cell culture fluids infected with each of the seven EAV strains and RNA from the live vaccine, Arvac, was detected by PCR using four sets of primers. The sensitivity of detection was increased from 100 to 1,000 times by performing nested PCR enabling the detection of RNA at a level of 0.5-5 PFU. Differentiation among the virus strains and the live vaccine was achieved by cutting the PCR-amplified products from three sets of primers with six restriction endonucleases. Using this procedure it was possible to distinguish among the seven EAV strains used.

Base Sequence↗
PubMed1995

Genotyping of isolates of Taylorella equigenitalis from thoroughbred brood mares in Japan.

Profiles of the genomic DNA of 104 strains of T. equigenitalis isolated from brood mares with contagious equine metritis in Hokkaido during the breeding seasons from 1980 to 1993, as well as those of five strains (SS28, EQ56, EQ59, EQ70 and HH139) previously isolated in Japan were examined after restriction digestion and crossed-field gel electrophoresis. These profiles were essentially identical to each other and the various isolates and strains appeared to have a common genotype, designated 'genotype J', with respect to two restriction enzymes, ApaI and NotI. These results suggest a common source for all these isolates obtained over the course of more than 10 years in Japan.

Animals↗
PubMed1995

Dacron coronary graft obstruction after composite graft replacement of aortic root.

Obstruction of the left coronary ostial anastomosis is a rare late complication after composite graft replacement of the ascending aorta and the aortic valve with separate Dacron coronary grafts. Intimal proliferation caused by the turbulent blood flow at this site may be the cause of the obstruction, which is considered a possible cause of late cardiac events such as sudden death and global myocardial infarction. We describe a case of tight stenosis at the left coronary ostial anastomosis in a 38-year-old woman with Marfan's syndrome who had undergone a composite graft replacement that employed separate Dacron coronary grafts.

Adult↗
PubMed1995

High implantation rate and consequently high pregnancy rate by in vitro fertilization-embryo transfer treatment in infertile women with antisperm antibody.

OBJECTIVE: To examine the effect of antisperm immunity on postfertilization steps, such as implantation of embryos and fetal growth in IVF-ET treatment of women with sperm-immobilizing antibodies. DESIGN: Retrospective analysis of clinical laboratory data. SETTING: The IVF-ET program of the Department of Obstetrics and Gynecology. The University of Tokushima, School of Medicine. PATIENTS: Eighteen women with sperm-immobilizing antibodies and 122 infertile patients with nonimmune etiology as controls. Infertile couples due to a male factor and with unknown etiology were excluded. INTERVENTIONS: All patients received the same IVF-ET program with GnRH agonist. MAIN OUTCOME MEASURES: Rates of fertilization and cleavage, implantation rate per embryo transferred and pregnancy rate (PR) in both test and comparison groups. RESULTS: The rate of fertilization in the antisperm group (61.3%) was significantly lower than that in the comparison group (76.8%). But the implantation rate per embryo transferred (23.5%) and consequently the modified PR per oocyte recovery procedure (34.4%) in immunologically infertile women were significantly higher than those in the comparison group (7.9% and 17.8%, respectively). CONCLUSIONS: Although sperm-immobilizing antibodies prevent sperm-egg interaction, they do not seem to have any adverse effects on achievement of pregnancy. Moreover, the existence of antisperm immunity in woman with antisperm antibodies is suggested to be favorable for successful pregnancy by the IVF-ET procedure.

Adult↗
PubMed1995

Identification and localization of immunoglobulin binding factor in bronchoalveolar lavage fluid from healthy smokers.

Immunoglobulin binding factor (IgBF), which is abundant in human seminal plasma, is known to bind immunoglobulin, interact with anti-Fc gamma RIII antibodies, and block pokeweed mitogen (PWM)-stimulated lymphocyte blastogenesis. In this study, we investigated whether IgBF is present in the lower respiratory tract, whose secretions come into contact with the external environment. For this, IgBF was measured in brochoalveolar lavage fluid (BALF) from 42 healthy normal subjects (23 nonsmokers and 19 smokers) by enzyme-linked immunosorbent assay (ELISA). IgBF was detected in BALF from these normal subjects, and its level was significantly higher in BALF from smokers (127.2 +/- 98.7 ng/ml versus 23.3 +/- 20.7 ng/ml). On gel filtration chromatography of BALF, IgBF was eluted in a region corresponding to a molecular weight of 27 kD. Western blot testing with a monoclonal antibody to IgBF indicated that IgBF in BALF had a molecular weight of 27 kD under nonreducing conditions and of 16 kD under reducing conditions. Thus, the migration pattern of IgBF in BALF corresponded to that of IgBF in seminal plasma. IgBF immunoreactivity was detected histochemically in mucus glands and goblet cells in the lower respiratory tract. These results demonstrate that IgBF is present in the lower respiratory tract, and that smoking may cause its increased production in this region.

Adult↗
PubMed1995

Retrieval of a migrated detachable coil--case report.

A 74-year-old female presented with intraventricular and subarachnoid hemorrhage due to probable rupture of a basilar artery (BA) aneurysm or a superior cerebellar artery (SCA) aneurysm. She was treated by endovascular therapy using detachable coils through the BA. The BA aneurysm was completely occluded, but part of a coil migrated into the BA from the SCA aneurysm during the procedure. The migrated coil was retrieved using a snare type endovascular retrieving device. The snare loop required concentric closure around the coil by simultaneous pulling of the corewire and a slight forward movement of the tip of the snare catheter. The SCA aneurysm was successfully occluded 1 week later using a shorter coil.

Aged↗
PubMed1995

Magnetic resonance imaging and histology of a large cystic meningioma--case report.

A 9-year-old boy presented with a meningioma containing a large cyst. Magnetic resonance (MR) imaging demonstrated tumor cells in the solid part of the tumor, part of the cyst wall, and cyst septum. The presence of the tumor cells in the thin cyst wall or the cyst septum is important to recognize preoperatively, and MR imaging is very useful to differentiate intratumoral cysts from peritumoral cysts in meningiomas.

Child↗
PubMed1995

[Fontan-type procedure for an adult case of double-outlet right ventricle (S, D, L)].

The double-outlet right ventricle with L-malposition (DORV (S, D, L)) is one of the rare congenital heart diseases. Intracardiac rerouting with a internal conduit has been indicated in principle to it as the radical operation. DORV (S, D, L) is often combined with the pulmonic stenosis (PS), and Rastelli's operation is indicated to the case in which release of PS is difficult. We report a case of DORV (S, D, L) combined with PS and the hypoplastic right ventricle which is treated by the Fontan-type procedure. The patient was a 35-year-old female who had undergone Glenn's operation at 10 years of age under the diagnosis of transposition of the great arteries. Recently she complained of aggravation of the cyanosis and dyspnea on exertion. After thorough examinations, the disease was diagnosed as DORV (S, D, L) with doubly committed VSD which was combined with severe PS, hypoplastic right ventricle (29% of normal) and left-sided juxtaposition of atrial appendages. The development of her distal pulmonary arteries was estimated well enough (PA-index 448 mm2/m2). We judged that intracardiac rerouting with an internal conduit could not be applied due to her severe pulmonic stenosis, and that Rastelli's operation as the biventricular repair was also impossible because of her hypoplastic right ventricle. Thus we adopted the Fontan-type procedure with a new septation in the right atrium, namely oblique partition, and attained a good result. To our knowledge, this case is the fourth case report in Japan of DORV (S, D, L) treated with the Fontan-type procedure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Evaluation on the perioperative left ventricular function of aortic valve replacement in patients with chronic aortic regurgitation].

To evaluate the perioperative left ventricular function in 36 patients undergoing aortic valve replacement (AVR) in patients with isolated chronic aortic regurgitation (AR), hemodynamic variables before and within the first 24 hours and one month after operation were measured with Swan-Ganz catheter and echocardiography. The patients were divided into two groups based on preoperative left ventricular end-systolic volume index (LVESVI): 5 patients had a LVESVI of 90 ml/m2 and greater (group I), 31 had a LVESVI smaller than 90 ml/m2 (group II). Left ventricular dimension at end-diastole and end-systole, left ventricular end-diastolic volume index at one month after operation significantly decreased in comparison with that of preoperation. However, left ventricular ejection fraction in the two groups were not improved, and left ventricular mass index in group I did not decreased. On the other hand, changes of cardiac index, stroke volume index and left ventricular stroke work index within the first 24 hours after operation were not significantly different between the two groups. The incidence of postoperative premature ventricular contraction in group I was significantly higher than that of group II. However, there was no difficult problems in postoperative management of the two groups. It is suggested that AVR in AR with left ventricular dysfunction can safely be operated and its postoperative management is similar to AVR in AR with no left ventricular dysfunction.

Adult↗
PubMed1995

Expression and characterization of human recombinant parental and mature L-histidine decarboxylases.

Human recombinant 74 kD parental (rHDC74) and 54 kD mature (rHDC54) histidine decarboxylases (HDCs) have been expressed in Sf9 cells and characterized. By immunoblot analysis, rHDC74 and rHDC54 were shown to be localized predominantly in the particulate and soluble fractions, respectively. rHDC74 exhibited histamine-synthesizing activity equivalent to that of rHDC54. An active particulate HDC was also detected in the pellets obtained from 10,000 and 100,000 g centrifugation of a cell lysate from the human basophilic leukemia cell line, KU-812-F (14 and 18% of the total activity, respectively). By four purification steps, rHDC54 was purified to homogeneity, as judged by silver staining of the SDS-polyacrylamide gel. The purified rHDC54 was eluted as a monomer form from a Superdex-200 FPLC column. The molecular mass of the enzyme was found to be approximately 54 kD on SDS-poly-acrylamide electrophoresis in the absence of 2-mercaptoethanol. Taken together, these results suggest that human HDC functions as both 74 and 54 kD forms having equivalent HDC activity, which are localized in the particulate and soluble fractions, respectively, and that the latter form exhibits its activity as a monomer form.

Animals↗
PubMed1994

Activation of K+ channels by ritodrine hydrochloride in uterine smooth muscle cells from pregnant women.

This study investigated the mechanism of activation of K+ channels by ritodrine hydrochloride in human myometrial smooth muscle cells. The patch-clamp technique was used for recording single channel currents. Ritodrine (10(-5) M) activated two types of K+ channels in cultured uterine smooth muscle cells from pregnant women: the Ca(2+)-activated K+ (KCa) channel and the ATP-sensitive K+ (KATP) channel. Forskolin (10(-4) M), an activator of adenylate cyclase, and protein kinase A activated the KCa channel. In addition, 10(-4) M GTP activated the KCa channel in inside-out patches using a pipette containing 10(-5) M ritodrine. The KATP channel was activated by protein kinase A, but not by 10(-4) M GTP. The beta-adrenoceptor agonist ritodrine activates two types of K+ channels: the KCa channel via direct gating by GTP-binding proteins and possibly via cAMP-dependent phosphorylation, and the KATP channel possibly via cAMP-dependent phosphorylation. These mechanisms partially explain the relaxing effect of ritodrine hydrochloride.

Cells, Cultured↗
PubMed1994

Use of the serum neutralisation test for equine viral arteritis with different virus strains.

Serum cross neutralisation tests were conducted with a recent American isolate (84KY-A1) and a European isolate, (Wroclaw-2) and compared with the prototype and modified viruses of the Bucyrus strain of equine arteritis virus by using virus specific immune horse sera. The modified Bucyrus strain was neutralised and showed high neutralisation titres with all the immune sera. The prototype Bucyrus strain was also substantially neutralised, followed by the 84KY-A1 strain. As a result of the tests with the modified Bucyrus strain as the antigen, 20 seropositive horses were discovered among home-bred horses which had no previous record of clinical equine viral arteritis. Heat inactivation of the sera at 62 degrees C for 30 minutes caused the disappearance of all but the most positive reactions. When the prototype Bucyrus strain was used instead of the modified virus, no positive reactions were detectable. A serological survey, using the Bucyrus strain in a microtitre neutralisation test, was conducted with 1656 horse sera collected between 1988 and 1990 in Japan. The test disclosed only eight foreign-bred horses positive to the virus; they had been imported as competition horses. No circumstantial evidence of an effect of such horses as a source of infection for horse populations free of the virus was obtained.

Animals↗
PubMed1994

Immunoglobulin binding factor: a new tumor marker for prostatic tumors.

Human seminal plasma contains an immunoglobulin gamma binding factor (IgBF) with an estimated molecular weight of 16 kD under reducing condition. IgBF was detected only in the prostate, including benign prostatic hypertrophy (BPH) and neoplasm. The present study was performed to determine whether IgBF is a useful prostatic marker. Serum IgBF levels were measured in patients with prostatic tumors and in control patients without tumor by radioimmunoassay. Serum prostatic-specific antigen (PSA), the standard prostatic marker, was also determined. Serum IgBF levels in patients with prostate cancer were significantly higher than those in age-matched controls (P < 0.05). Also, patients with BPH tended to have elevated IgBF levels than the controls, although the values were not statistically significant. In control patients, serum IgBF levels increased with advancing age. There was no correlation between serum levels of IgBF and PSA in patients with prostate cancer. Using cut-off level at 28.5 ng/ml (2 S.D. above the mean IgBF level of age-matched control), the sensitivities were 41.2% (7/17) for prostate cancer, 23.1% (6/26) for BPH, and 5.6% (1/18) for control patients. In conclusion, serum IgBF is a useful marker in the diagnosis of patients with prostatic tumor, and in evaluating the course of treatment.

Adolescent↗