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Biomedical subjects

W A Schmidt

Publications and source records attributed to W A Schmidt.

At least 73 records · Page 4Linked to original sources
PubMed1985

Comparison of specific red-cell adherence and immunoperoxidase staining techniques for ABO(H) blood-group cell-surface antigens on superficial transitional cell carcinoma of the bladder.

The presence or absence of blood-group antigens have been used to predict the clinical course of patients with superficial transitional cell carcinoma of the bladder. Antigen loss has been associated with neoplastic change. The red-cell adherence test has been the most widely accepted method of antigen determination, but this technique has inherent weaknesses. Recently, the immunoperoxidase assay has been used to detect antigens on tumor cells. We compared 30 patients using the red-cell adherence and immunoperoxidase methods on adjacent microtome cut sections. The red-cell adherence and immunoperoxidase methods performed similarly (86%) when assessing antigen presence or absence. However, the immunoperoxidase method was clearly superior in: 1) specificity for antigens on tumor cells and normal internal controls; 2) localization of antigen; 3) demonstration of cellular morphology; 4) increased objectivity of analysis; 5) ease of reproducibility; and 6) cost effectiveness.

ABO Blood-Group System↗
PubMed1985

Estrogenic activity of DDT: estrogen-receptor profiles and the responses of individual uterine cell types following o,p'-DDT administration.

The administration of o,p'-dichlorodiphenyltrichloroethane (o,p'-DDT) to immature rats stimulates DNA synthesis and cell division in the uterine luminal epithelium (LE), stroma (S), and myometrium (M). The time course of DNA synthesis/cell division in the S and M is similar following administration of o,p'-DDT or 17 beta-estradiol, but the maximum response following pesticide treatment is only 70% of that produced by the hormone. In the LE both compounds yield the same maximum response, but the time course of DNA synthesis/cell division is delayed following o,p'-DDT administration relative to 17 beta-estradiol treatment. The patterns of estrogen receptor retention in uterine nuclei following o,p'-DDT administration are prolonged relative to those observed after 17 beta-estradiol treatment. o,p'-DDT thus produces the uterine hyperplasia characteristic of estrogens, but the magnitude and timing of the response is dependent on the specific cell type observed and is different from that produced by estradiol.

Animals↗
PubMed1984

Ultrastructure of trypan blue-induced ocular defects II. Cornea and mesenchyme.

Using scanning and transmission electron microscopy, the histological and cytological alterations induced in the developing eye by trypan blue were examined. Microphthalmic and anophthalmic eyes were analyzed from 16-day rat fetuses whose dams had received a teratogenic dose of trypan blue. Cell and tissue damage within cornea and mesenchyme were assessed. Corneas from the treated groups were undulating and uneven owing to abnormal lens placement and corneal cell injury. Extensive extracellular spacing, few cell-to-cell contacts, patchy glycocalyces, and abnormal surface morphology characterized the corneal cells of treated tissues. Mesenchyme of severely malformed eyes typically filled the eye field in regions normally occupied by retina and lens. As a tissue, mesenchyme lacked organization and those surface features normally present in component cells were altered. Mesenchymal cells were packed so closely that extracellular spaces were nearly obliterated. Microvilli, filopodia, and lamellipodia, cell processes observed in normal mesenchyme, were altered in both number and structure. The cytoplasm of mesenchymal cells was condensed and decreased in volume. These data suggested that 1) in this trypan blue ocular model, virtually all major tissue types were morphologically altered; 2) because healthy mesenchyme and cornea are required for normal development of lens, optic vesicle and ocular adnexa it follows that abnormal cornea and mesenchyme also will compromise these tissues; and 3) since necrotic reminants were not present, this trypan blue model probably causes developmental arrest. The most likely teratogenic pathway is presented with emphasis on the cell surface as a probable site of dye action.

Abnormalities, Drug-Induced↗
PubMed1983

Ultrastructure of trypan blue induced ocular defects: I. Retina and lens.

The histological and cytological basis of trypan blue-induced ocular defects were studied using scanning and transmission electron microscopy. Microphthalmic and anophthalmic eyes of 16-day rat fetuses were utilized from dams exposed to a teratogenic dose of trypan blue. Retinal and lenticular anlagen were specifically examined for architectural and cellular changes. Nearly all severely abnormal eyes showed no evidence of retina development: Of 41 such eyes, only two retinal rudiments were observed. Those eyes with mild microphthalmia always demonstrated retinae although architectural changes were present. In every abnormal eye, some degree of lenticular morphogenesis was always present. Lenses were small, displaced in the eye field, and arrested at the lens vesicle stage. Lens cells were markedly undifferentiated and thus lacked most of the cytological features normally present at this developmental stage. Neither retinal nor lenticular rudiments were necrotic despite major architectural and cytological disturbances. The data offer three conclusions: First, the absence of necrosis suggests that trypan blue causes developmental arrest in this eye model; second, absence of retinae is most likely due to primary failure of optic vesicle development; third, lack of lens differentiation is attributed to absence of the retina, the primary lens inducer.

Abnormalities, Drug-Induced↗
PubMed1982

The vasculature of the human penis: a reexamination of the morphological basis for the polster theory of erection.

The morphology of human penile blood vessels has been studied to characterize columns of smooth muscle found in the intima. Although previous workers (Kiss, 1921; Conti, 1952) termed these intimal pads or polsters and concluded that they were actively responsible for the production of erection, more recent work has questioned these conclusions (Benson et al., 1980; Newman and Tchertkoff, 1980). Serial sections were taken throughout the length of the penis from 11 cadavers and stained with various histopathological stains. Numerous polster-like structures were found, but all could be identified as either branch points in vessels, intimal cushions located at branch points, or arteriosclerotic lesions at various stages of development. None of these structures seem capable of functioning in the manner attributed to them by Conti (1952) and others. Furthermore, comparison of the structures found in the present study to illustrations of polsters in Conti's paper suggest that these are identical. The present study refutes the polster theory of erection and leaves open to further question the mechanisms involved in the control of blood flow into and within the penis.

Adult↗
PubMed1981

Metastasizing malignant juxtaovarian tumor with terminal hypercalcemia: a case report.

A juxtaovarian tumor of probable mesonephric origin in an 18-year-old white woman recurred six years later with a pelvic mass and widespread peritoneal metastases. Chemotherapy with cyclophosphamide, Doxorubicin, and cis-platinum induced a partial response of approximately one year duration. The terminal disease course was associated with hypercalcemia and disseminated intravascular coagulation. At autopsy, there were extensive abdominopelvic tumor masses with pleural deposits.

Adult↗
PubMed1981

Coronavirus-associated antibodies in nasopharyngeal carcinoma and infectious mononucleosis.

Coronavirus-like particles are found within the cytoplasm of NPC tumor cells, within the cytoplasm of the tumor cells of the regional metastases, and within tumor cells grown on nude mice. For the immunologic identification of the coronaviruses, the cultures of human tracheal epithelium (MRC-C) were used and inoculated with a known coronavirus strain. Whereas blood sera from NPC patients (n = 73) contain significantly elevated antibody titers against corona viruses, unselected sera from patients without NPC showed a low antibody titer (n = 83). Only patients suffering from infectious mononucleosis (n = 40) showed a titer pattern similar to that of NPC patients. For demonstration of antigen-antibody reaction within the NPC tumor cell cytoplasm, sera with a high antibody content against coronaviruses deriving from other than NPC patients or anticoronavirus sera from rabbits were used. By indirect immunofluorescence, the NPC tumor cells showed a bright cytoplasmic fluorescence. No fluorescence was seen when tumor cells were exposed to human sera with known low or absent corona antibody titer or to normal rabbit sera. The results indicate that next to a DNA virus infection (EBV), an RNA virus infection (coronavirus) may play a role in NPC as well as in infectious mononucleosis.

Antibodies, Viral↗
PubMed1981

Penile polsters: functional structures or atherosclerotic changes?

The distribution of blood flow within the penis during erection and detumescence is thought to be controlled by polsters, columns of smooth muscle cells within the intima of penile arteries and veins. We have examined penile tissue from 4 men and 2 children, and have been unable to find incontrovertible evidence of polsters as classically described. Occasional structures superficially resembling polsters were encountered not only in penile tissue but also in vessels in the spermatic cord in patients undergoing vasectomy. In each instance these structures were recognizable as either branching points of vessels, intimal smooth muscle cell cushions or atherosclerotic lesions at various stages of development. Our findings strongly refute the hypothesis that polsters contribute to the normal physiology of erection.

Arteries↗
PubMed1981

Massive postpartum corpus luteum cyst: a case report.

A young woman presented with an asymptomatic unilateral adnexal mass at six weeks postpartum. Her abdomen and pelvis had been considered unremarkable upon examination at parturition, at which time no adnexal masses were palpated. At laparotomy a 20 cm. right ovarian cyst was found, which was shown microscopically to be of corpus luteum origin. Each of the features--size, rapid development, and presentation in the postpartum state--is most unusual.

Adult↗
PubMed1981

[The latex-IgM-test in virus diagnostic: determination of cytomegalovirus antibodies (author's transl)].

We examined the practical value of the Latex-IgM-test in diagnostic virology. Sera of patients suspected to have a cytomegalic infection were used for serological investigation. Cytomegalovirus produced in cell cultures was incubated with serum from patients. The resulting virus-antibody complex was removed by centrifugation and sensibilized Latex particles were added (anti IgG and anti IgM). The quantity and type of the bound antibody could be determined in this way. The sera were checked by parallel determination by another reliable method, the neutralization test. Immunoglobulins G and M separated and tested for antibodies. The usefulness of the Latex-IgM test for the routine diagnostics could be evaluated in the present study.

Antibodies, Viral↗
PubMed1981

Three-dimensional subgross morphology of the human endometrium.

A method is described for subgross, structural assessment of endometrial configuration. Human uteri from autopsy and surgical pathology were preserved in formalin and sectioned at 1-mm intervals. A procedure for staining, dehydration, and clearing was developed to achieve three-dimensional resolution of endometrial morphology. Processed specimens were sealed in translucent heavy plastic bags for the purpose of storage, easy manipulation under the dissecting microscope, and for photographic documentation. For simultaneous comparison with standard histological preparations, selected areas of sealed specimens were punched-out and paraffin sections made. This simple method can easily be applied to the future investigation and classification of focal premalignant, dysplastic, anaplastic, and atypical changes in the endometrium. The significance of this approach and its possible application to specimens obtained at dilatation and curettage is discussed.

Endometrium↗
PubMed1981

Primary ovarian nongestational choriocarcinoma. Report of a case in a young woman of childbearing age.

Nongestational, pure ovarian choriocarcinoma is decidedly rare; the unequivocal diagnosis is rarely established in women of childbearing age. Differentiation of nongestational from gestational trophoblastic neoplasia is crucial, the prognosis and therapy being distinct in each type. We report a case of primary ovarian, nongestational, pure choriocarcinoma in a 27-year-old woman treated with surgery and aggressive chemotherapy. The distinction of nongestational from gestational choriocarcinoma and its variants, including latent choriocarcinoma, is discussed.

Adult↗
PubMed1981

Verruciform xanthoma of the penis.

We describe herein a patient with a verruciform xanthoma of the penis. This histologically distinctive lesion is usually confined to the oral mucosa, although two cases occurring on the vulva have recently been reported. To our knowledge, this lesion has not been previously described in other sites. Biopsy for histopathologic examination is required to aid in the identification of this unusual entity. Verruciform xanthomas have been benign, although a squamous cell carcinoma subsequently developed in one patient whose oral lesions were associated with leukoplakia.

Adult↗
PubMed1980

Aortopulmonary septal defect and longevity.

A patient with a large congenital aortopulmonary septal defect lived for 46 years. Such lesions are usually fatal in early life unless corrected. Because the anatomic and physiologic adjustments were evident and relatively stable, the case calls for examination of the practice of prognostication.

Adolescent↗