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Biomedical subjects

W Stolz

Publications and source records attributed to W Stolz.

At least 199 records · Page 11Linked to original sources
PubMed1988

[Transvaginal echography. An application in the diagnosis of cervical incompetence].

It has already been demonstrated that abdominal ultrasound is an adequate method for measuring the cervix in pregnancy. The use of the vaginal route for such measurement is new. We have been using for the vaginal approach an ultrasound transducer of 5 mHZ with an angle of sweep of 240 degrees. The study was carried out on 23 pregnant women at the 28th week of pregnancy who had been admitted because of threatened premature labour with possible cervical incompetence; and on 20 cases of normal pregnancy also at the 28th week, which is the time when we do glucose estimations normally in our antenatal clinics. The result of our work shows that this ultrasonic method through the vagina gives us much more accurate measurements of the cervix than digital vaginal examination does. A mean difference of 12.3 mm in the length of the cervix was found in normal pregnancies (46.3 mm) and in cases where there was a question of cervical incompetence (34 mm). Furthermore the phenomena of shortening, dilatation of the cervix and a funnel-shape of the internal os are ultrasound signs of value in diagnosing incompetent cervix. Further advantages of the transvaginal approach are that there is no need for the bladder to be filled previously, and that the organs are nearer which improves the ultrasound picture. All the same, it is to be emphasized that transvaginal ultrasound can only be a factor to be added to clinical examination in the diagnosis of the incompetent cervix.

Cervix Uteri↗
PubMed1988

[Congenital poikiloderma with verrucous hyperkeratosis. An unusual form of Thomson's syndrome?].

A 50 year old male patient suffered from poikilodermatous skin since his 14th year of life. During the past 5 years hyperkeratotic plaques and squamous cell carcinomas developed, leading to metastases into lymph nodes and the lung and fatal outcome. To our knowledge, up to now 6 cases of congenital poikiloderma (Thomson-syndrome, Rothmund-Thomson-syndrome) in conjunction with verrucous hyperkeratosis and squamous cell carcinoma have been reported in the literature.

Carcinoma, Squamous Cell↗
PubMed1987

Morphometric and ultrastructural analyses of melanocytes, nevus cells, and melanoma cells.

Cytological atypia, revealed in the course of routine light microscopy, is considered a valuable indicator of malignancy in melanocytic lesions. A clear definition of the term cytological atypia, however, is lacking. Therefore, by morphometric analysis of ultrathin sections of 11 malignant melanomas (7 invasive, 3 in situ, and 1 lentigo maligna melanoma) and 10 compound nevi, we evaluated the discriminating power of the various facets of cytological atypia, i.e., nuclear area, area of the nucleolus, area of the total cell, and nuclear irregularity. In each case, at least 50 intraepidermal melanocytic cells were examined. The two-sided U-test showed significant differences between intraepidermal nevus and melanoma cells, with regard to the mean values (mean) and standard deviations (s) of the nuclear area (mean and s, p = 0.00011), area of the nucleolus (mean, p = 0.00043; s, p = 0.00011), and area of the total cell (mean, p = 0.00011; s, p = 0.00093). However, only the mean values and standard deviations of the nuclear area allowed a clear distinction in each individual case. The area of the nucleus can be estimated in the course of routine histology. We therefore think that the size and variation of the nuclear area should be considered in the histological differential diagnosis between malignant melanomas and benign nevi.

Cell Nucleolus↗
PubMed1986

Natural killer cells in leukemogenesis.

In order to relate a reduced natural killer (NK) cell function to leukemogenesis, NK cells in the spleen and peritoneal exudate cells, with and without stimulation by Corynebacterium parvum, were tested in mice of various strains after split dose irradiation and after leukemogenic treatment with butyl- and methylnitrosourea. The investigations included also mice submitted to non-leukemogenic irradiation (1 X 1.5 and 1 X 4.5 Gy) and mice submitted to an additional treatment with hydrocortisone, which delays leukemia development after methylnitrosourea. There was, indeed, a NK-cell depression, but no major differences were seen between mice prone to leukemia development and those after cytotoxic, but nonleukemogenic, treatment.

Animals↗
PubMed1984

Studies on natural killer cell activity and the influence of Corynebacterium parvum on murine T-cell leukemogenesis induced by butylnitrosourea.

Butylnitrosourea (BNU) was used to induce thymic lymphomas in BDF1 mice. During and after the 12-week BNU exposure the spontaneous NK cell activity against YAC-1 cells and that arising 4 days after stimulation with Corynebacterium parvum (CP) were measured, as were the mitogen responses of splenic T and B cells. In addition to BNU, groups of mice received multiple injections of the interferon inducer CP during or after the BNU exposure period. The results show a slight impairment of the NK cell activity by BNU and also after the injections of CP depending heavily on the treatment protocol. After the multiple injections of CP, either into BNU-treated mice or into controls, no further stimulation by CP was possible. The mitogen responses, reduced after BNU, were further reduced after the additional treatment. Both effects can be explained by the known induction of suppressor cells by CP. Although these treatments had pronounced effects on the parameters tested in vitro there was no significant influence on the development of thymic lymphomas in vivo.

Animals↗
PubMed1983

Circulating Sézary cells in the diagnosis of Sézary syndrome (quantitative and morphometric analyses).

Plastic-embedded circulating Sézary cells were examined in semithin and thin sections (assisted by the nuclear contour index-NCI). Eight cases of Sézary syndrome were analyzed as well as 11 controls (3 cases of widespread eczemas and 8 cases of erythroderma), 7 cases of mycosis fungoides, and 3 healthy individuals. Discriminating criteria between Sézary syndrome and benign diseases were sought: in addition to Sézary cells (NCI greater than 6.5) intermediate lymphocytes (5.0 less than NCI less than or equal to 6.5) proved to be helpful. Cases with Sézary syndrome were clearly differentiated when the following 3 ultrastructural criteria were fulfilled: (1) Sézary cells (SC) greater than 9%; (2) intermediate lymphocytes (IL) greater than 20%; (3) the sum of SC and IL greater than 37%. A good correlation between thin and semithin sections was obtained (correlation coefficient for Sézary cells r = 0.82). Usually the values of SC were slightly higher on thin sections. The diagnosis of SS can be made on semithin sections when the ultrastructural criteria are fulfilled. In this way 8 of 12 samples of Sézary syndrome were correctly classified. Therefore, semithin sections (studied by light microscopy) are recommended as a routine method in the diagnosis of cases suspected of Sézary syndrome, whereas thin sections (studied by electron microscopy) appeared to be necessary in problem cases only.

Adult↗
PubMed1982

Cutaneous immunoblastic T-cell lymphoma.

The case of a 69-year-old male patient with an unusual type of malignant lymphoma is presented. Clinically, it was at first characterized by follicular papules and erythematous patches, later, by the development of cutaneous tumors and enlarged lymph nodes, and by a severe, finally excruciating pruritus. Treatment with PUVA (psoralen-ultraviolet-A) combined with 40--80 mg prednisolone and then with chemotherapy [COPP regimen (cyclophosphamide, vincristine, procarbacine, prednisone), high-dosage methotrexate followed by citrovorum factor rescue] was not successful. The patient died of pneumonia 2.5 years after the onset of the first clinical symptoms. An immunoblastic infiltrate was observed histologically and electromicroscopically in the initial lesions of the skin. Therefore, the diagnosis of a cutaneous immunoblastic T-cell lymphoma was tentatively made at the beginning, which was later confirmed in numerous biopsies and laboratory investigations. Immunocytologically and enzymecytochemically, the infiltrating cells were shown to be immature T cells; in the lymph nodes, numerous immunoblasts and large Sézary cells was observed in the peripheral blood, though there were no very large Sézary cells or blast cells. In the autopsy, a systemic involvement with an atypical lymphoid infiltration was found in numerous internal organs. The special nature of this case justifies its classification as high-grade malignant lymphoma and its differentiation from normal cases of mycosis fungoides. In contrast, mycosis fungoides generally fulfils criteria typical of low-grade malignant lymphomas.

Aged↗
PubMed1982

Autoradiographic studies of the diurnal rhythm of the cell proliferation in the adrenal cortex of the rat.

With the aid of the autoradiographic technique we examined the question of diurnal or circadian rhythm of the cell proliferation as well as the mitotic rate in the three zones of the adrenal cortex of the rat. To evaluate the diurnal rhythm it is necessary to run experiments within 24-hour intervals. In order to examine observed variations as to their reproducibility we prolonged our investigations over a period of 72 hours. The proliferation activity as well as the mitotic rate in the zona glomerulosa show no diurnal rhythm. This is not so in the zona fasciculata. Here we find a correlated circadian rhythm for both parameters.

Adrenal Cortex↗
PubMed1975

Incidence of laterality effects in mandibular and manual performance of dichoptic visual pursuit tracking.

In dichotic pursuit auditory tracking tasks (PAT) subjects match a continuously varying pure tone presented to one ear with a second tone presented to the other ear and controlled by unidimensional movements of part of their motor system. In previous studies in which tonal frequency was varied, performance was significantly better when the tone controlled by a speech articulator (tongue, jaw) was presented to the right ear, rather than the left, but not if the tone was hand controlled. This study examined a visual analog of the PAT in which subjects matched the vertical position of a continually moving horizontal line (target) presented on one side of their point of fixation, with a second line (cursor) presented on the other side of their fixation point. Two predictions were confirmed for 12 right handed subjects: that there would be no significant laterality effect for articulatory (jaw) tracking because previous auditory tracking findings were speech related; and, that there would be a significant laterality effect (cursor right field-left hemisphere) for right hand tracking because of the development of a specialized sensorimotor integration mechanism for eye-right hand coordination in the left hemisphere. Alternative explanations for the right hand tracking results, and for the nonsignificant trend towards a laterality effect (cursor left field-right hemisphere) for left hand tracking, were discussed.

Adult↗
PubMedDate not supplied

Increase in telomerase activity during progression of melanocytic cells from melanocytic naevi to malignant melanomas.

During successive cell divisions of mortal cells the length of the telomeres (TTAGGG repeats in vertebrates) at the end of chromosomes decreases. It has been suggested that this process is responsible for cellular senescence. Expression of the ribonucleoprotein telomerase appears to prevent shortening of telomeres in germ-line cells and cancer cells. The purpose of this study was to investigate telomerase activity in melanocytic lesions and its possible role in the multi-step tumor progression model of malignant melanoma. To quantify the level of telomerase activity both in cultured cells and in fresh tissue samples the TRAP (telomeric repeat amplification protocol) ELISA was used. Eight cell lines of malignant melanoma, 3 primary cultures of fibroblasts, 36 melanocytic naevi, 5 atypical melanocytic naevi, 3 Spitz's naevi, 31 primary malignant melanomas and 13 metastases of malignant melanomas were investigated. Also 34 samples of skin (22 samples of perilesional skin and 12 samples of normal skin) were analysed. In our experiments all melanoma cell lines were strongly positive, whereas in fibroblasts telomerase activity could not be detected. Of the primary melanomas and metastatic melanomas, 90.3% and 92.3%, respectively, were strongly positive, and of the atypical melanocytic naevi, 80% were positive. Of the 36 common melanocytic naevi only 10 (27.7%) expressed weak telomerase activity and of the 34 samples of human skin, 4 (11.7%) expressed very weak telomerase activity. Our results indicate that telomerase activity increases from benign melanocytic naevi to atypical naevi and further to malignant melanoma and metastatic melanoma cells, and therefore may play a role in tumour initiation and progression.

Adolescent↗