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Biomedical subjects

A Dam

Publications and source records attributed to A Dam.

At least 37 records · Page 2Linked to original sources
PubMed1992

Placental-like alkaline phosphatase and DNA flow cytometry in spermatocytic seminoma.

Immunohistochemical analysis was done on 7 testicular tumors classified as spermatocytic seminoma (SS) and 25 classic seminomas. Except for a few scattered cells, the spermatocytic seminomas were negative for placental-like alkaline phosphatase (PLAP); the classic seminomas were all positive for this enzyme. The SS also were negative for alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (hCG), and leukocyte common antigen (LCA). The ploidy of the seven tumors of SS was as follows: two, diploid; two, near-diploid; one, tetraploid; one, aneuploid; and one, uninterpretable. The essentially negative staining of SS for PLAP was strikingly different from the pattern in classic seminoma. Thus, staining for this enzyme is useful for making the differential diagnosis between classic seminoma and SS. To differentiate between malignant lymphoma and SS, staining for leukocyte common antigen is helpful.

Adult↗
PubMed1992

Ploidy of testicular carcinoma in situ.

The ploidy of carcinoma in situ and invasive germ cell tumors of the adult testis was compared by DNA flow cytometry. Irrespective of the tumor type with which it was associated, the median DNA index of carcinoma in situ was about the same as that of seminomas and higher than the DNA index of invasive nonseminomatous germ cell tumors. These data indicate that seminoma and carcinoma in situ cells are not only phenotypically similar but also have the same ploidy.

Adult↗
PubMed1991

Cytogenetic study of a nodular hyperplasia of the thyroid after irradiation for Hodgkin's disease.

We describe cytogenetics of a case of nodular hyperplasia of the thyroid with papillary microcarcinoma following radiotherapy for Hodgkin's disease. The chromosomal pattern found was very heterogeneous with a clonal abnormality of chromosome 10, among others. Together with some recent data from the literature, this finding may point to an important role of chromosome 10 abnormalities in the pathogenesis of benign and malignant thyroid neoplasms.

Adult↗
PubMed1991

Dual parameter flow cytometry for deoxyribonucleic acid and intermediate filament proteins of residual mature teratoma. All tumor cells are aneuploid.

Most testicular germ cell tumors of adults are presumably derived from polyploid carcinoma in situ. Thus, one would expect that even highly differentiated teratoma components are aneuploid and that it is unlikely to find diploid tumor cell (sub)populations. We studied 10 residual mature teratomas (RMTs) using a dual parameter flow cytometry procedure. Nuclear DNA was stained with propidium iodide and cytoplasmic intermediate filament proteins, in particular, cytokeratins, with fluorescein isothiocyanate-labeled specific monoclonal antibodies. Cells in RMTs, immunoreactive with antibodies to cytokeratins were considered to be tumor cells. These were always found to be aneuploid, in agreement with the available cytogenetic data on these tumors. The diploid cells present in RMTs were devoid of cytokeratins; therefore, these cells represent the nonmalignant normal host stromal and inflammatory cells. These results, in accordance with our earlier finding, indicate that diploid testicular germ cell tumors are extremely rare in adults, and that even the histologically benign somatic tissues in RMT after polychemotherapy are aneuploid.

Adult↗
PubMed1990

Cytogenetic analysis of murine embryo-derived tumors.

The possible relationship among malignancy, differentiation, and chromosomal constitution of primary embryo-derived tumors was studied. Tumors were induced by transplanting 7-day-old mouse embryos under the kidney capsule of syngeneic BALB/c recipients. Transplantation of 101 embryos resulted in 18 tumor-bearing mice: 36 teratocarcinomas; 18 teratomas; and 27 yolk sac tumors. Some of the yolk sac tumors proved to be retransplantable for several generations. Cytogenetic investigation of the primary embryo-derived tumors revealed that the majority of teratocarcinomas (82%) were chromosomally normal, whereas almost all (83%) karyotyped teratomas and yolk sac tumors had a highly abnormal chromosomal constitution. Most common aberrations were polyploidy; overrepresentation of chromosome 1, 6, 15, or 19; and an underrepresentation of chromosome 2, 4, 14, or a sex chromosome.

Animals↗
PubMed1990

Ploidy of malignant mediastinal germ-cell tumors.

The ploidy of 19 primary mediastinal malignant germ-cell tumors (GCT) was measured. Six tumors were (near) diploid. The median DNA index of the 13 remaining tumors was 1.91, indicating that most aneuploid tumors were near tetraploid. Seminomas and nonseminomatous GCTs were similar with respect to proportion of diploid tumors and median DNA index of the aneuploid tumors. The ploidy of mediastinal malignant GCTs is remarkably different from that of testicular GCTs of adults, but more similar to that of testicular GCTs of infancy. The pathogenesis of malignant mediastinal GCTs is probably different from that of testicular GCTs of adults, and more similar to the pathogenesis of infantile testicular GCTs. The difference in ploidy between mediastinal malignant GCTs and GCTs of the adult testis may help to differentiate between a primary extragonadal malignant GCT and a mediastinal metastasis from a primary testicular GCT.

Adolescent↗
PubMed1990

Cytogenetics of thyroid follicular adenomas.

We present the results of a cytogenetic study of three cases of follicular adenoma of the thyroid. All three cases had a numerical strongly abnormal karyotype with most abnormalities (eg, +4 or +5, +7, +9, +12, +16) in common, possibly indicating that this cluster of abnormalities might be specific for follicular adenomas. For benign tumors, the three cases showed a remarkably abnormal karyotype. These cases are another example of benign tumors with chromosomal abnormalities that might be specific for follicular adenomas.

Adenoma↗
PubMed1989

Chromosomal changes in human primary testicular nonseminomatous germ cell tumors.

A cytogenetic analysis of 14 primary testicular nonseminomatous germ cell tumors has been carried out after short term tissue culture. The modal chromosome numbers ranged from 53 to 113, in agreement with flow cytometric determination of the DNA content of the tumors. At least one copy of an i(12p) was present in 12 tumors. Two tumors, however, lacked that marker. Some chromosomes are apparently overrepresented, whereas others are underrepresented, although some differences between seminomas and nonseminomas were noticed.

Analysis of Variance↗
PubMed1989

Cytogenetic analysis of ten human seminomas.

A cytogenetic analysis of ten seminomas has been carried out after direct harvesting of the tumor cells. Modal chromosome numbers ranged from 63 to 112. These numbers were in agreement with flow cytometric determination of the DNA content of the tumors. Eight tumors had at least one copy of an i(12p) among other chromosomal abnormalities. Two seminomas lacked the i(12p).

Adult↗
PubMed1989

A malignant mixed gonadal stromal tumor of the testis with heterologous components and i(12p) in one of its metastases.

A malignant mixed gonadal stromal tumor with mesenchymal heterologous elements of the testis is presented. This entity has been described in the ovary, but not hitherto in the testis. Karyotyping and ploidy measurement was done of the primary tumor and of an inguinal and lung metastases. The DNA ploidy and modal chromosome numbers were in agreement with each other in all samples. The most significant cytogenetic finding was the presence of the metacentric germ cell tumor marker i(12p) in an inguinal metastasis. This marker has been demonstrated in testicular and ovarian germ cell tumors and in a mixed Müllerian tumor, which raises the question of a possible relationship between the pluripotency of these tumors and the presence of i(12p).

Chromosome Aberrations↗
PubMed1989

Ploidy of primary germ cell tumors of the testis. Pathogenetic and clinical relevance.

The ploidy of testicular germ cell tumors (GCT), a heterogeneous group of neoplasms, was studied by DNA flow cytometry. The DNA index for infantile yolk sac tumor (N = 10), seminomas (N = 20), and nonseminomas (N = 36), was: 1.91, 1.66, and 1.43, respectively. These values differed significantly one from another (p less than 0.01). The seminoma and nonseminoma components of combined tumors (N = 16) had a significantly different median DNA index of 1.61 and 1.40, respectively. Three of the 10 infantile yolk sac tumors, but only one of the 72 testicular GCT of adults were diploid. The consistent aneuploidy of testicular GCTs of adults might be helpful in the differential diagnosis of primary nongerm cell tumors of the testis, and in differentiating between metastases of testicular GCTs and primary extragonadal malignant GCTs. These data fit into a model of pathogenesis of testicular GCTs of adults in which all tumors, with the possible exception of spermatocytic seminoma, pass through a seminoma stage. Tumor evolution seems to result from net loss of chromosomes from a (near)tetraploid carcinoma in situ cell. The pathogenesis of infantile yolk sac tumor might be different from that of testicular GCTs of adults.

Aneuploidy↗
PubMed1988

Cytogenetics of 12 cases of renal adenocarcinoma.

The cytogenetics of 12 cases of renal adenocarcinoma are presented. Clonal abnormalities were found in nine patients. Worth mentioning are abnormalities of the X chromosome (1 X) and the chromosomes #1(3 X), #3(3 X), #7(4 X), #8(4 X), and #14(2 X). From our data and data from the literature it appeared that the chromosomal regions 3p11-p21, 1q21, 14q22, and Xp11 are important for the oncogenesis of renal cell carcinoma as well as increased dosage of chromosome #7 and loss or abnormalities of chromosomes #8 and #14.

Adolescent↗
PubMed1981

Salpingitis in poultry. II. Prevalence, bacteriology, and possible pathogenesis in egg-laying chickens.

Among 116,886 egg-laying chickens slaughtered 438 (0.37%) were condemned because of salpingitis (Table I). Profuse growth of a single bacterial species was demonstrated in 96 out of 150 randomly selected cases of salpingitis (Table II). E. coli was isolated from 64 cases (43%). P. haemolytica, Pr. mirabilis and P. gallinarum occurred next most frequently, and made up 26 cases. Staph. aureus, Str. faecalis and Moraxella sp. finally accounted for six cases. A mixed flora was demonstrated in 16 cases (11%) while unspecific growth or no growth was recorded in 38 cases (25%). The bacteriological findings in cases of salpingitis in egg-laying chickens routinely received for post mortem examination were in accordance with the findings above in carcasses condemned because of salpingitis, except in a single case in which Bact. fragilis was obtained in pure culture. Salmonella spp. could not be demonstrated. No correlation could be demonstrated between the nature of the pathological changes and the bacteriological findings. Nineteen different O-groups of E. coli were found, O2 being the one occurring most frequently (Table III). Changing the environment from a floor type with bedding to cages or sloping wire floor without bedding does not seem to have resulted in a change of bacterial species associated with salpingitis in egg-laying chickens. The food-hygienic implications of salpingitis seem to be the same for laying hens as for broilers.

Animal Husbandry↗
PubMed1980

Salpingitis in poultry. I. Prevalence, bacteriology and possible pathogenesis in broilers.

The prevalence of salpingitis in broilers at slaughter seems to be rather constant, constituting 0.02--0.03% of the broilers slaughtered (Table I & Figure 1). Profuse growth of Escherichia coli in pure culture was obtained from the salpinx of all 123 investigated carcasses with chronic salpingitis. Primary blood agar plates examined showed a pure culture as to O-group as well. Of 22 different O-groups demonstrated, 01, 02, 07 and 053 were most prevalent, constituting 47% of the strains (Table III). Salmonella spp. were not demonstrated. Etiology, pathogenesis and possible food hygienic consequences are discussed in the light of the present findings.

Animals↗