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Biomedical subjects

M Kamada

Publications and source records attributed to M Kamada.

At least 19 recordsLinked to original sources

Establishment of the human BSMZ breast cancer cell line, which overexpresses the erbB-2 and c-myc genes.

A new cell line, designated BSMZ, was established from a malignant pleural effusion from a woman with breast cancer. This line has a doubling time of 27 h and has now been cultured for over 120 passages. The large, rounded BSMZ cells grow as both a monolayer and as aggregations in suspension. Intracytoplasmic lumen, a finding consistent with results from cells derived from mammary tissue, was detected on ultrastructural analysis. Injection of BSMZ cells into nude mice resulted in the growth of solid tumors 4 weeks after inoculation. The solid tumor was identical to the original BSMZ cells in microscopic and electron microscopic studies. These cells possess an average of 80 chromosomes. Expression of erbB-2 and c-myc genes was increased by 10-fold, while there was no detectable overexpression of the N-ras and c-myb genes. Southern analysis has revealed amplification of the erbB-2 and c-myc loci. The BSMZ cell line may therefore provide a useful model for the study of human breast cancer and overexpression of the erbB-2 gene.

Adult

Interstitial deletion of chromosome 16q: 16q22 is critical for 16q- syndrome.

Partial deletion of 16q is rare; to our knowledge only 12 cases have been published. Fryns et al. [Hum Genet 38:343-346, 1977] described the first of these cases and proposed a new clinical entity. Our patient was a girl and had many minor anomalies of the kind often observed in 16q- syndrome. Severe failure to thrive due to emesis and diarrhea were also observed. High resolution banding methods showed that the chromosome constitution of the patient was 46,XX,del(16)(q22.1q22.3). This suggests that 16q22 is critical for the syndrome.

Chromosome Deletion

Tissue-specific mosaicism for trisomy 21 and congenital heart disease.

Cytogenetic studies in a girl with ventricular septal defect and mosaicism for trisomy 21 showed that trisomy was present in most cells from the myocardium and lung but in only a minority from the skin and lymphocytes. These findings emphasize the importance of tissue-specific mosaicism as a cause of certain cardiovascular diseases.

Child, Preschool

The complete sequence of African horsesickness virus serotype 4 (vaccine strain) RNA segment 5 and its predicted polypeptide compared with NS1 of bluetongue virus.

The complete sequence of RNA segment 5 of the African horsesickness virus serotype 4 (AHSV-4) vaccine strain was determined from cDNA clones inserted into pBR322. The RNA is 1751 bp long (M(r) 1.12 x 10(6)) and contains an open reading frame encoding a protein of 548 amino acids (M(r) 63,122) with a net charge of +0.5 at neutral pH. A comparison of the sequence of AHSV-4 segment 5 with that of segment 6 of bluetongue virus (BTV) serotypes 10 and 17 revealed 49.2% and 48.9% nucleotide similarity, respectively, and 31.4% amino acid similarity. However, AHSV-4 segment 5 has no significant similarity to BTV segment 5. In addition, Northern blot hybridization showed that full-length AHSV-4 segment 5 cDNA cross-hybridized with the corresponding genes of all serotypes of attenuated AHSV.

African Horse Sickness Virus

A mosaic case of isodicentric chromosome 18.

A case of mosaicism of isodicentric chromosome 18 is reported. Dicentric chromosome 18 occurs rarely and only five cases of isodicentric chromosome 18 have been documented. A high resolution banding method revealed that the karyotype of the patient was mos 46,XX/46,XX idic(18)(pter-->q21.3::q21.3-->pter), and the ratio of normal and abnormal clones was 1:1. The clinical manifestations, resembling those of trisomy 18 syndrome, were affected by both partial trisomy 18pter-->q21.3 and partial monosomy 18q21.3-->qter.

Child

Heterophile antigens in serous cystadenocarcinoma of the human ovary.

As the aberrance of carbohydrate moieties, the appearance of heterophile antigens in human ovarian cancer tissue was studied using various heterophile antigens and antibodies together with antisera raised in rabbits by immunization with extracts of human ovarian cancer tissues. In the immunodiffusion test, rabbit antisera reacted with a heat-stable, perchloric-acid extractable antigen that was different from CEA and CA125 and possessed Hanganutziu-Deicher (HD)-type specificity in all 4 specimens of serous cystadenocarcinoma of the ovary. Furthermore, a pathologic serum with strong HD-antibody complex formed a precipitin line with one of them. In the cancer tissue, we also immunochemically demonstrated the presence of rat-erythrocyte antigens. However, other types of heterophile antigens, such as Paul-Bunnell and Forssman, were not detected. These results suggest that HD-type antigens appear in serous cystadenocarcinoma of the human ovary, one in broad distribution and some in specific cases.

Animals

Etiological implication of autoantibodies to zona pellucida in human female infertility.

PROBLEM: Autoantibodies to zona pellucida (ZP) have been implicated as a cause of infertility in woman by three lines of clinical and laboratory evidence. METHOD: First, positive anti-zona activities, as assessed by the passive hemagglutination reaction (PHAR) using bovine red blood cells sensitized with porcine zona antigen, were detected in 45 of 1,872 serum samples collected from infertile women, but in only three (two nonpregnant and one pregnant) of 592 serum samples from control subjects. Their incidence in 320 women with unexplained infertility (5.6%) was much higher than that in 1,552 women with infertility of known cause (1.7%, P < 0.01), which was comparable to the incidence observed in 193 age-matched fertile nonpregnant and pregnant women (1.5%, P < 0.05). None of the serum samples from 292 age-matched adult men and 100 children of between 5 and 10 years old gave a positive PHAR. Second, follow-up study for a minimum of 2 years with treatment revealed that no pregnancy occurred in 11 infertile women with a consistently positive PHAR, and only three pregnancies in 19 infertile women with a fluctuating positive PHAR. Third, three of seven serum samples from women who gave a consistently positive PHAR produced strong immunofluorescence reactions on human ZP even after adsorption with porcine and human AB blood cells. Pre-exposure of human ZP to the sera showing positive immunofluorescence, including that of one patient undergoing an in vitro fertilization program, greatly diminished the number of spermatozoa of normal quality that bound to and penetrated across human ZP. CONCLUSIONS: The observed high incidence of anti-zona activities and long-term resistancy to treatment in women with unexplained infertility may be closely correlated with inhibition of sperm-egg interaction by anti-zona autoantibodies produced in these women.

Antibody Formation

Epizootiological aspects of type 1 and type 4 equine herpesvirus infections among horse populations.

The dissemination of equine herpesvirus types 1 (EHV-1) and 4 (EHV-4) among various horse populations in Japan was investigated through the isolation and typing of virus strains from horses with respiratory diseases. Type specific monoclonal antibody pools were used for the typing of isolates. The 42 strains of EHV-1 and 64 strains of EHV-4 were isolated from 4593 nasal swabs and/or blood plasma samples collected from 3326 horses during a period from 1979 to 1990. All the strains of EHV-1 were isolated from racehorses only and during the winter season exclusively, when the epizootic of respiratory diseases occurred among racehorse populations at two Training Centers of the Japan Racing Association. In contrast, the strains of EHV-4 were isolated from horses irrespective of the season, facility, or horse population; foals and yearlings in breeding farms and our institute, rearing horses in rearing farms, and racehorses. Especially, 4 strains of EHV-4 were isolated from plasma samples containing buffy coat cells. We believe this is the first reported case of EHV-4 cell-associated viremia in the world. All 87 strains isolated from aborted fetuses were identified as EHV-1. The results suggest that EHV-1 is responsible for epizootic respiratory diseases in racehorses in the winter and abortion among mares at the late stage of gestation, and that EHV-4 causes respiratory diseases throughout the year among all horse populations.

Abortion, Veterinary

Effect of sperm-immobilizing antibodies on the acrosome reaction of human spermatozoa.

OBJECTIVE: To study by a triple stain technique the effect of sperm-immobilizing antibodies on the acrosome reaction of human spermatozoa. DESIGN: The spermatozoa were allowed to swim up and culture in a medium containing 7.5% (vol/vol) serum with sperm-immobilizing antibodies or control serum up to 6 hours. Sperm mobility was analyzed, and the percentage of live acrosome reacted spermatozoa was determined. SETTING: Samples were collected from patients referred to university hospital infertility clinics. MATERIALS: Serum samples were drawn from seven patients with sperm-immobilizing antibodies. All the sera were heat activated and stored at -40 degrees C until use. Semen samples were taken from two healthy donors. RESULTS: During culture for 6 hours, the percentage of live sperm showing the acrosome reaction increased significantly (P less than 0.01) in the control group but not in the sperm-immobilizing antibodies group. However, the inhibitory effect of sperm-immobilizing antibodies on the acrosome reaction was reversed when sperm was reincubated in medium with control serum (P less than 0.01). CONCLUSIONS: Sperm-immobilizing antibodies block fertilization at least in part by inhibiting the acrosome reaction of human spermatozoa.

Acrosome

Detection of equine immunoglobulin-secreting cells by a plaque assay.

A protein A-hemolytic plaque assay was applied to detect immunoglobulin (Ig)-producing cells in horse peripheral blood, using pokeweed mitogen as a B lymphocyte activator. A maximum number of Ig-secreting cells was obtained when horse peripheral blood lymphocytes were cultured in a medium containing horse serum. The number of Ig-secreting cells in young horses (2 years old) was lower than that in adult horses (6 to 23 years old). In addition, the plaque formation was unchanged from blood samples kept at 4 degrees C for 24 hours, while blood samples kept for 72 hours did not yield plaques. These results indicate that the plaque assay is a reliable and useful method for detecting Ig-secreting cells in the peripheral blood of the horse.

Animals

Tissue kallikrein clearance by the liver--effect of plasma components on kallikrein uptake by cultured rat hepatocytes.

Rat urinary kallikrein (RUK) injected intravenously to the rat rapidly disappeared from the blood circulation and mainly distributed to the liver. RUK was also incorporated to the primary cultured rat hepatocytes. The amounts of RUK incorporated into the hepatocytes increased by preincubation of RUK with rat plasma. These results and SDS-PAGE analysis suggested some plasma components may be involved in tissue kallikrein clearance in the blood.

Animals

Prevalence of virulent Rhodococcus equi in isolates from soil and feces of horses from horse-breeding farms with and without endemic infections.

The prevalence of virulent Rhodococcus equi in isolates from soil and feces of foals on a farm with endemic R. equi infections was significantly higher than that of a farm with no history of the disease. Foals bred on a farm with the endemic disease might be constantly exposed to virulent R. equi in their environment.

Actinomycetales Infections

Effective prophylaxis of thrombosis by antithrombin III concentrate in a pregnant woman with congenital antithrombin III deficiency: relations between plasma antithrombin III activity and the plasma levels of hemostatic molecular markers.

The value of antithrombin III (AT III) concentrate and a standard criterion for its use were examined in a pregnant woman with congenital AT III deficiency by continuous monitoring of plasma AT III activity and the plasma levels of hemostatic molecular markers. The rates of improvement of various markers after AT III administration (frequency of improvement/frequency of administration) were as follows: fibrinopeptide A (FPA) 82%, D-dimer 70%, fibrinopeptide B beta 15-42 73%, beta-thromboglobulin 60%, and platelet factor 4 50%. There was no significant correlation between the plasma AT III activity and all plasma FPA values, but FPA values of over 3.9 ng/ml showed a significant negative correlation with AT III activity: AT III activity (%) = -6.59 x FPA (ng/ml) + 125, r = -0.851, p less than 0.02. We therefore recommend continuous monitoring of the plasma FPA level and administration of AT III concentrate when the FPA level is elevated. According to the regression line shown above, plasma AT III activity should be raised to 100% to keep the FPA level below 6.0 ng/ml with 95% confidence limit.

Adult

Characteristics of Staphylococcus aureus isolated from lesions of horses.

Seventy-six Staphylococcus aureus strains isolated from various lesions of horses were characterized. All of the 76 strains were identified as biotypes B (38.2%) and C (61.8%). Of 55 strains tested, 42 (76.4%) were differentiated into 7 coagulase types. Coagulase types V and VII were predominant in the metritis strains. Coagulase type II was found most frequently in the strains from phlegmon, dermatitis, sinusitis, empyema sinus, and nasal catarrh. Forty-two (55.3%) of the 76 strains were differentiated into 24 phage patterns. Twenty (58.8%) of 34 typable strains from metritis were lysed by the human group I phage 52, and group II phages 3A, 3C, 55 and 71. Forty-five (59.2%) of the 76 strains were resistant to 1 or more of 6 antibiotics. Strains resistant to penicillin G, irrespective of source, were most frequent (95.6%). Forty (93.0%) of 43 strains resistant to penicillin G alone or in combination with other antibiotics produced beta-lactamase. Only 8 (10.5%) of the 76 strains produced enterotoxins A (n = 2), B (n = 1) or C (n = 5), and they all were isolated from metritis. Only 1 strain isolated from phlegmon and 2 from metritis produced exfoliative toxin (ET) and toxic shock syndrome toxin-1 (TSST-1), respectively. The latter 2 strains also produced enterotoxin C. The results of the present study showed the first evidence of the presence of both ET- and TSST-1-producing S. aureus isolated from horses.

Animals