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Biomedical subjects

M Kamada

Publications and source records attributed to M Kamada.

At least 145 records · Page 8Linked to original sources
PubMed1994

Expression of glutathione S-transferase-pi in human ovarian cancer as an indicator of resistance to chemotherapy.

Expression of glutathione S-transferase-pi (GST-pi) was examined immunohistochemically in relation to the response to chemotherapy with cisplatin in 61 patients with primary ovarian cancer who had not received any chemotherapy before surgery. GST-pi were detected in the cancer tissues of 33 patients (54.1%). Of 28 clinically measurable lesions after surgery, 10 of the 11 tumors (90.9%) showing positive GST-pi staining were drug resistant (no change or progressive disease), whereas 6 of the 17 tumors (35.3%) showing negative staining were drug resistant. This difference in the response rates of the two groups was significant (P < 0.005). The survival period of patients with GST-pi-positive tumors was also significantly shorter than that of those with GST-pi-negative tumors (P < 0.005). These data strongly suggest that GST-pi expression in tumor cells is related to drug resistance of patients with epithelial ovarian cancer and is a useful marker of a poor prognosis.

Adult↗
PubMed1994

Rapid detection of African horsesickness virus by the reverse transcriptase polymerase chain reaction (RT-PCR) using the amplimer for segment 3 (VP3 gene).

The complete sequence of the major core protein (VP3) gene of African horsesickness virus serotype 4 (AHSV-4; vaccine strain) was determined by analysis of a complete cDNA clone representing segment 3. The RNA was 2,789 bp long and a comparison of its sequence with that of bluetongue virus serotype 10 (BTV-10) revealed 58% nucleotide similarity. Based on these data, the reverse transcriptase-polymerase chain reaction (RT-PCR) technique was applied to the specific detection of AHSV using a pair of primers designed for AHSV-4 VP3 gene. Approximately 230 bp of PCR products were amplified by RT-PCR from the total RNA extracts (mRNA and dsRNA) of Vero cells infected with eight serotypes of AHSV. No product was observed analogous to other orbiviruses. The supernatant of the infected cell culture fluid without any RNA purification was also suitable as a template for RT-PCR after being denatured at 94 degrees C for 5 min. The sensitivity of this method was between 10(0) and 10(1) TCID50 when viral RNA from the supernatant of infected cell culture was subjected to RT-PCR. The whole procedure for detecting the virus RNA by RT-PCR could be carried out within 5 h. The RT-PCR with AHSV VP3 gene as a target was found to be a simple, highly specific and sensitive assay for AHSV.

African Horse Sickness Virus↗
PubMed1994

Pathology of equine pneumonia associated with transport and isolation of Streptococcus equi subsp. zooepidemicus.

Seven horses that died of pneumonia associated with transport yielded Streptococcus equi subsp. zooepidemicus (S.z.) from their pulmonary lesions. These lesions were divisible roughly into two types, serous haemorrhagic pneumonia and multiple foci of coagulative necrosis, which were considered to reflect a temporal difference in the process of lesion formation. Immunohistologically, S.z. antigen was detected in both types of lesion. Acute necrotic lacunar tonsillitis was considered to play an important role in the onset of the pneumonia.

Animals↗
PubMed1994

The complete sequences of African horsesickness virus serotype 4 (vaccine strain) RNA segment 2 and 6 which encode outer capsid protein.

The complete sequences of RNA segment 2 and segment 6 of African horsesickness virus serotype 4 (AHSV-4) vaccine strain were determined from cDNA clones inserted into pBR 322. The RNAs of segment 2 and 6 are 3229, 1566 bp long respectively and both contain an open reading frame encoding proteins VP2 and VP5 of 1060, 505 amino acid residues. The estimated molecular weight of VP2 was 124,178 dalton and that of VP5 was 56,793 dalton. Their noncoding end sequences were 5'GTTTAA . . . and . . . ACATAC3' (segment 2), 5'GTTTAT . . . and . . . ACTTAC3' (segment 6). They were different from orbivirus characteristic terminal sequences, which were 5'GTTAAA . . . and . . . ACTTAC3'. The comparison of both sequences of AHSV-4 segment 2 and 6 with those of segment 2 and 5 of bluetongue virus (BTV) serotype 10 revealed 53% nucleotide similarity and 23% amino acid similarity (segment 2), and 58% nucleotide similarity and 46% amino acid similarity (segment 6). In the same way, the comparison of both sequences of the vaccine strain with those of the virulent strain segment 2 and segment 6 of AHSV-4 revealed 91% nucleotide and 96% amino acid similarity (segment 2), and 98% nucleotide and 98% amino acid similarity (segment 6).

African Horse Sickness Virus↗
PubMed1994

Detection of African horsesickness virus by reverse transcriptase polymerase chain reaction (RT-PCR) using primers for segment 5 (NS1 gene).

The reverse transcription followed by the polymerase chain reaction (RT-PCR) technique was applied to the detection of African horsesickness virus (AHSV) using primers specific for attenuated AHSV serotype 4 segment 5 (NS1 gene). Total RNA which contains both messenger RNA and genomic dsRNA was extracted by the acid guanidinium-phenol-chloroform method from the AHSV infected Vero cells and was used as templates to optimize the RT-PCR. A pair of primer (NP2-NP32) amplified the product of the expected size from all serotypes of attenuated AHSV when four pairs of primers were tested. Using this primer pair, no RT-PCR product was detected from the RNA samples extracted from ten other orbiviruses infected cells and their virions. In addition, RT-PCR using a serial dilution of RNA samples suggested that AHSV was efficiently detected from 1 to 2 cells of the cell monolayer infected with 10(6) TCID50 of AHSV. The RT-PCR concerning with total RNAs of AHSV NS1 gene was found to be a specific and sensitive method for the detection of AHSV.

African Horse Sickness↗
PubMed1994

Detection of immunoglobulin binding factor by enzyme-linked immunosorbent assay using two monoclonal antibodies.

Immunoglobulin binding factor (IgBF) found in human seminal plasma may be involved in suppressing antibody production against sperm in the female and male genital tracts. In the present study an enzyme-linked immunosorbent assay (ELISA) for IgBF was developed using monoclonal anti-IgBF antibodies. The sensitivity of the method was 20 pg/ml. The method was used to quantify IgBF in sera from women. In addition high levels of IgBF was found in cervical mucus of the uterus and in bronchial washings. The present results suggest that IgBF is found in tissues that are exposed to the external environment and may be a component of the local immunity system.

Adult↗
PubMed1994

[Antitumor effect of SN-38, active form of CPT-11, on human colorectal cancer cell line].

The in vitro sensitivity testing for four human colorectal cancer cell lines to seven chemotherapeutic drugs including CPT-11, derivative of camptothecin, and its active form SN-38 were determined. MTT assay revealed that SN-38 was the most active for all four cell lines tested and its IC50's were very close to its clinically achievable plasma concentration. Relationship between exposure time and cytocidal effect of SN-38 was also investigated using MTT assay, topoisomerase-I (Topo-I) immunoblot analysis and DNA relaxation-assay, showing that IC50 value, Topo-I protein and Topo-I activity were decreased soon after the administration of SN-38 and reached to the plateau level at 24 hours. We conclude that SN-38 is very potent for colorectal cancer and the optimal schedule of CPT-11 can be the more continuous form of administration capable of as long as 24 hours exposure of its active metabolite, SN-38.

Antineoplastic Agents, Phytogenic↗
PubMed1994

[Action of synthetic progestin].

Chemical compound that can bind the progesterone receptor in the nucleus and cause proliferative change of the endometrium is designated as progestin (gestagen, progestogen). Progesterone (natural progestin) is secreted from corpus luteum of the ovary. Synthetic progestin can be divided into two groups: (1) progesterone derivatives, such as medroxyprogesterone acetate and (2) testosterone derivatives, such as norethisterone. The former has progestane structure and a marked progestational activities but little estrogenic and androgenic activities. While, most of the testosterone derivatives keep androgenic activities and show even estrogenic activities due to its estrane structure or production of estrogen as the metabolite. Thus, understanding the characteristics of mode of action in each synthetic progestin, we should select the appropriate one for clinical treatment.

Estrogen Antagonists↗
PubMed1994

[Mitral valve aneurysm in a patient with mitral regurgitation: a case report].

A 66-year-old man admitted to our hospital complaining of severe dyspnea. Echocardiography demonstrated severe mitral regurgitation and an abnormal echo at the anterior leaflet of the mitral valve. It was a persistent bulge that protruded toward the left atrium throughout systole and diastole. Left ventriculography also demonstrated the same abnormal shadow of the mitral valve. At the operation, it was seen that two of the chordae tendineae of the anterior leaflet had ruptured and a small aneurysm, approximately 10 mm in length, originated from the lateral part of the leaflet. The aneurysm protruded into the left atrium and had neither rupture nor perforation. Because the aneurysm of the mitral valve was too large to resect and repair the valve, it was replaced with St. Jude Medical Valve (29 M). IABP was needed at the weaning from cardiopulmonary bypass, but he recovered gradually well afterwards. The excised anterior leaflet showed myxomatous degeneration, but had no vegetation and rheumatic change. Microscopic examination of the valve aslo revealed myxomatous degeneration and no signs of the inflammation.

Aged↗
PubMed1993

High expression rate of Tn antigen in metastatic lesions of uterine cervical cancers.

The significance of altered expression of MN blood group antigens was examined by studies on the expressions of Thomsen-Friedenreich antigen (T antigen) and Tn antigen in primary and metastatic lesions of 29 human uterine cervical cancers. These antigens were measured by the avidin-biotin-peroxidase (ABC) method with peanut agglutinin (PNA) lectin for T antigen and Vicia villosa agglutinin (VVA) lectin for Tn antigen. Proportion of cancer cells expressing Tn antigen was higher in the metastatic lesions than in the primary tumors in 10 of the 29 cases, less in the metastasis than in the primary tumor in one case, and similar in the primary and metastatic lesions in the other 18 cases. Reaction for Tn antigen was positive in 24 (82.8%) of the 29 metastases, and in 17 (58.5%) of the 29 primary lesions. Thus, the rate of Tn antigen expression was significantly higher in the metastases than in the primary lesions (P < 0.05). On the other hand, there was no significant difference between the immunoreactivities of T antigen in metastases and primary tumors. These findings support our previous suggestion that expression of Tn antigen is closely related to the metastasis to regional lymph nodes and may reflect an important role of this carbohydrate in the process of metastasis of cervical cancer.

Adenocarcinoma↗
PubMed1993

Tn antigen, a marker of potential for metastasis of uterine cervix cancer cells.

BACKGROUND: The expressions of Thomsen-Friedenreich antigen (T-Ag) and Tn antigen (Tn-Ag), precursors of MN blood group antigens, were examined in the tissues of squamous cell carcinoma of the uterine cervix from 111 patients to determine their clinicopathologic significance with regard to the biologic behaviors of cancer cells and the clinical course of the patients. METHODS: T-Ag and Tn-Ag were measured by the avidin-biotin-peroxidase (ABC) method with peanut (Arachis hypogaea) lectin (PNA) and Vicia villosa agglutinin (VVA), respectively. RESULTS: Unlike expression of T-Ag, that of Tn-Ag was correlated closely with vascular permeation of cancer cells, their parametrial spread and metastasis to the pelvic lymph nodes, and also with a low 5-year survival rate. No correlation was found between expression of Tn-Ag and other parameters, such as the clinical stage or histologic type. Furthermore, Tn-Ag expression was independent of the degree of cancer involvement in the fibromuscular stroma of the cervix, which seems to be a marker of the aggressiveness of cancer cell proliferation. CONCLUSIONS: These results indicate that Tn-Ag expression is a useful indicator of the potential for metastatic potential of cancer cells. Thus, a combination of estimations of the degree of cancer involvement in the cervical stroma and Tn-Ag expression seems the most useful for predicting the prognosis of patients with cervical cancer.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1993

Protein characterization of Babesia equi piroplasms isolated from infected horse erythrocytes.

Proteins of Babesia equi piroplasms were characterized. The piroplasms of B. equi were purified by lysis of infected horse erythrocytes with N2 gas cavitation followed by separation in Percoll density-gradient centrifugation. The relative molecular weights (Mr) of major proteins separated by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis were 18, 28, 30, 41, 43, 54, 66.5, and 96 kDa. Immunoblot analysis using serum from an experimentally infected horse revealed six immunodominant proteins of 15, 18, 28, 30, 41, and 96 kDa. Two immunodominant proteins of 18 and 28 kDa were membrane-bound proteins as revealed by Triton X-114 phase partitioning.

Animals↗