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W Schmidt

Publications and source records attributed to W Schmidt.

At least 361 records · Page 20Linked to original sources
PubMed1992

[Use of computer-assisted image analysis for the detection of immunohistochemical receptor status in breast cancer. Immunohistochemical densitometry receptor analysis--IRDA].

A method for the evaluation of the immunohistochemical staining score of steroid receptors in breast cancer using computer-based image analysis is presented. The optical density of tumour cell nuclei was measured using kryostat sections and, using a control section as reference, an objective threshold for specific staining was defined. In intensively stained sections, a good correlation with visual scoring was achieved, but in 9 out of 16 sections, which were regarded as receptor-negative by visual scoring, a specific receptor-positive staining was demonstrated by image analysis. Next to the percentage of positive cells (PP) and the mean staining intensity (SI), a histogram of the receptor concentration in positive nuclei was calculated. The method allows, besides an objective evaluation and documentation, an exact definition of a threshold for specific receptor measurement and furthermore shows the pattern of receptor concentration in the tumour cell nuclei. Hence, the method could contribute towards a more widespread use of immunohistochemical receptor analysis.

Breast↗
PubMed1992

[Noninvasive function tests in the evaluation of vascular reactivity in pregnancy and pregnancy-induced hypertension].

At present, there is an increasing discussion regarding the change of the prostacyclin/thromboxane ratio as an aetiological factor of pregnancy-induced hypertension (PIH). By means of videophotometric capillaroscopy in the capillaries of the nailfold, it is possible to visualise the resulting changes in the microcirculation. This method employs a special illumination microscope (magnification of the optical system x 560). Red blood cell velocity is measured under test conditions and microcirculatorical reaction capacity on ischaemic stress. Studies were conducted on healthy non-pregnant women and on healthy pregnant women as well as on patients suffering from pregnancy-induced hypertension. A markedly reduced velocity of red blood cells in patients with pregnancy-induced hypertension was seen as a sign of vasoconstriction, namely, 0.53 mm/sec. versus 0.74 mm/sec. Furthermore, these patients have a higher reactivity to ischaemic stress, probably also as a result of the already existing vasoconstriction; however, the duration of the hyperaemic phases is reduced in pregnancy-induced hypertension. By this method, an insight can be gained into microcirculation in pregnancy and in pregnancy-induced hypertension. In addition, as preliminary studies have already shown, the influence exercised by different medications on microcirculation can be assessed.

Blood Flow Velocity↗
PubMed1992

[Experiences up to now with the ultrasound dissection instrument in gynecologic oncology].

The energy of high frequency ultrasound is used to disrupt cellular structures. Since the water content of each individual cell is of utmost importance for the physical destruction of the cell, there may be a tissue-selective effect in respect of tissues such as epithelium (high water content) and mesenchyma (low water content). The various therapeutic modalities are described in the following four cases. Ultrasonic tumor destruction was highly effective with regard to maximum reduction of tumor masses, especially for tumor sites which could not be removed by conventional tumor surgery. Blood vessels and nerves surrounded by tumor could be carefully and completely dissected--even in advanced stages. Peritoneal metastases from an ovarian carcinoma could be removed entirely, as well as the metastases within a tumor bulk (e.g. ureter within tumor mass); also the layers of tissue which were lost could be visualized again. So far, no increase in complications during and after surgery has been observed.

Adult↗
PubMed1992

[Recurrence of vulvar cancer--treatment, experiences and results].

At the University Hospitals of Heidelberg (1970-1988) and Homburg/Saar (1988-1990), 182 patients with vulvar carcinoma were treated. 51 patients had a recurrence of vulvar carcinoma and 21 patients showed a persistence of this tumour. 19 women had a second recurrence of vulvar disease. In these cases, therapy ranged from local surgery to exenteration, depending on the site and tumour extension. 18 patients underwent successful reconstructive surgery. Prognosis was better in cases with local recurrence in comparison to distant sites of metastatic progression (i.e. inguinal nodes or disseminated disease) (p less than 0.001). The five-year survival (after diagnosis of recurrent disease) for patients with early onset of recurrence (less than 20 months after initial therapy) was 28% compared to 68% for patients with late onset of recurrent disease (p less than 0.01).

Female↗
PubMed1992

[Results of treatment in vulvar cancer from 1970 to 1990].

From 1970-1990, 159 patients with invasive malignant tumours of the vulva (150 squamous cell carcinomas) underwent surgery at the University Hospitals, department of gynaecology. Heidelberg (1970-1988) and Homburg/Saar (1988-1990). 73% of the patients were more than 60 years old and 3% were less than 40 years old. The mean age was 69 years. 30% of the patients had diabetes mellitus. As a standard therapy, 101 patients had radical vulvectomy with bilateral inguinal node removal in accordance with S. Way. If nodes were found to be positive, the inguinal/pelvic region was irradiated postsurgically with 40-50 Gy. The 5 years survival rate for all patients with vulvar carcinoma was 69%. For early stage carcinomas (pT1, depth of invasion < or = 1 mm) a restricted radical therapy should be considered. 9 patients with early stage carcinomas survived disease-free for a period of 70 months. Significant prognostic differences were noticed if node histology was N- as opposed to N+ (p < 0.001), if depth of invasion was < or = 1 mm as opposed to > 10 mm (p < 0.001), if stage was pT1 as opposed to pT2 to pT4 (p < 0.001) or if lymphangiosis carcinomatosa (p < 0.01) was present or not. Prognostic differences were also noticed, if cytological grading was done in accordance with Broders (p < 0.09). 27 patients had successful reconstructive surgery with local cutaneous or myocutaneous flaps at the time of initial surgery. The median recovery period after radical vulvectomy with bilateral inguinal lymph node excision was 22 days. The median recovery period after radical vulvectomy with bilateral node removal and reconstructive surgery was 25 days. Early recurrence of carcinoma (< or = 6 months after initial therapy) was 5.9%, late recurrence was 12%.

Aged↗
PubMed1992

Bioavailability of vinpocetine and interference of the time of application with food intake.

In a pilot study based on an open cross-over design involving four phases, the relative bioavailability of the eburnamenine derivative vinpocetine (CAS 42971-09-5) was investigated in 8 healthy volunteers in relation to different times of drug administration relative to food intake. The substance was applied orally as 10 mg film tablets. The areas under the plasma concentration-time curves (AUC) amounted to 27.3 +/- 18.1 ng.h/ml (fasting) and 42.8 +/- 27.4 up to 54.3 +/- 38.4 ng.h/ml (non-fasting, intake before and after meal, resp.). The relative bioavailability under non-fasting conditions was found to be approx. 60 to 100% higher than under fasting conditions.

Adult↗
PubMed1992

[A clinical evaluation of MAb BW 835/6 in breast and ovarian cancer].

Studies with the 99mTc-labeled murine monoclonal antibody BW 835/6 in patients suspected of breast (n = 7) or ovarian cancer (n = 8) showed insufficient depiction of primary tumors and metastases of breast cancer, but promising results in the detection of primary tumors in ovarian cancer without metastases. The small number of patients does not allow statistical analysis.

Adult↗
PubMed1992

Pharmacokinetics of isometronidazole. Basic model and estimation of the kinetic parameters from experimental data.

For the optimal timing of application of radiosensitizers in a course of radiotherapy it is important to know the sensitizer concentration at the time of irradiation. We have studied the pharmacokinetics of the hypoxic cell sensitizer isometronidazole in man and mouse and analyzed the data on the basis of an open two-compartment model after extravasal application. The parameter estimation is performed directly to avoid estimation biasing and data points from blood and tissue compartments are approximated simultaneously. The values obtained differ significantly from the estimations calculated by other authors for the same data.

Animals↗
PubMed1991

Immunocytochemical analysis of the cytoskeleton of the human amniotic epithelium.

The amniotic epithelium constitutes a diffusion barrier controlling the passage of solutes and water between the amniotic cavity and maternal circulation. With the present immunocytochemical approach, we have shown that several major components of the cyto-skeleton, i.e., actin, alpha-actinin, spectrin and ezrin, are preferentially associated with the apical and lateral cell surfaces of the human amniotic epithelium. Keratins are distributed throughout the entire cytoplasm, whereas vimentin mainly forms a perinuclear scaffold. These findings indicate a role of the various components of the cytoskeleton in the structural integrity and modulation of cell shape and junctional permeability.

Actinin↗
PubMed1991

[Doppler ultrasound in obstetrics--contribution to understanding reverse flow in the umbilical artery].

"Reverse Flow" as a Doppler sonographic finding indicates the appearance of retrograde blood flow in the diastolic part of the cardiac cycle. It has so far not been observed in uncomplicated pregnancies and seems to be an indicator of severe deterioration of the foetal condition. Several pathophysiological hypotheses are discussed in this paper on the basis of own results and the findings of other investigators.

Blood Flow Velocity↗
PubMed1991

[Discolored amniotic fluid--results of prenatal diagnosis and clinical significance].

7000 pregnancies were analysed after genetic amniocentesis in respect of the further course and results of prenatal diagnosis (observation period 1975-1988). In 3.1% (217 cases) samples of amniotic fluid were discoloured. Vaginal haemorrhages prior to amniocentesis were recorded with significantly higher incidence (18%) in patients with discoloured amniotic fluid than in a control group (n = 217) with normal colour of the amniotic fluid (4.6%) (p less than 0.001). Miscarriages and chromosome anomalies occurred more often in the study group (3.7%/2.8%, control group: 0.9%/1.8%, n.s.). The risk of miscarriages was increased in cases with sanguineous amniotic fluid if the amniotic fluid alpha-fetoprotein values were enhanced at the same time. Significant differences were observed in respect of the incidence of foetal malformations in patients with discoloured amniotic fluid (7.8%) and in the control group (2.3%) (p less than 0.01). Borderline or definitely pathological amniotic fluid AFP concentrations were found often if the amniotic fluid was discoloured (6.9%, control group 3.2%). If discoloured amniotic fluid was sampled, foetal malformations should be excluded sonographically. In 82% of all cases with discoloured amniotic fluid and foetal malformations pathological sonographic findings and/or enhanced MS-AFP values were recorded even prior to amniocentesis.

Amniocentesis↗
PubMed1991

[Value of vaginal ultrasonography in noninvasive assessment of the endometrium of the postmenopausal uterus].

The endometrial carcinoma shows an increasing incidence and represents today the most frequent malignoma of the female pelvis. Until now all techniques of detection of this carcinoma or its precursors are invasive and thus are not suitable for screening investigations. Vaginosonography, as the first non-invasive diagnostic method, now supplies knowledge about the state of the endometrium. At the Gynaecological Department of the University of Homburg/Saar, West Germany, 221 patients had been preoperatively subjected to vaginosonography before they underwent surgery. Sonographical and histological findings corresponded in atrophic endometrium in 82%, in regular, perimenopausal endometrium in 91%, in endometrial polyps and hyperplasia of the endometrium in 56%, and in endometrial carcinoma in 79%. With regard to the detection of endometrial cancer, a specificity of 96%, a sensitivity of 93%, a positive predictive value of 79% and an accuracy of 96% were established. Thus, according to our experience, vaginosonography represents a valid, non-invasive diagnostical method as a suitable instrument for screening the endometrium.

Adult↗
PubMed1991

Effects of maximal and submaximal exercise under normoxic and hypoxic conditions on serum erythropoietin level.

This study was carried out to investigate the influence of different exercise regimens on serum immunoreactive erythropoietin concentration (EPO). The same untrained male subjects performed bouts of maximal and submaximal exercise (60 min at 60% of maximal performance) under normoxia (n = 10) and normobaric hypoxia (PIO2 92 mmHg, n = 9). Five of them were exposed to hypoxia for 90 min under resting conditions (RTH). [EPO] was unchanged up to five hours after maximal (MEN) and submaximal (SEN) exercise under normoxia. After RTH, [EPO] increased after 3 hours by 5.0 mU/ml (p less than 0.01). Submaximal exercise under hypoxia (SEH) led to a similar increase in [EPO] (after 3 hours: + 5.5 mU/ml), which remained elevated the following days (after 24 h: + 6.1 mU/ml, 48 h: + 5.3 mU/ml; ANOVA p less than 0.001). Maximal exercise under hypoxia (MEH) had no significant effect. The results indicate that exercise has no immediate effect on serum [EPO], whereas the higher EPO level one and two days after SEH could result from the occurring hemodilution as is indicated by a slight negative correlation between [EPO] and Hct (r = 0.59, p less than 0.001). The number of reticulocytes increased after all hypoxic experiments and after MEN without any correlation to [EPO].

Adult↗
PubMed1991

[Comparison of perineal sonography and abdominal ultrasound examination in placenta praevia].

This study describes a comparison between two different ultrasound methods used to localize a low-lying placenta or a placenta previa. The methods implemented were the abdominal ultrasound and the so-called "perineal scan", an ultrasound examination of the female urogenital tract, which is performed by using the perineum as an acoustic window. Between 1985 and 1988, 84 patients, suspected of having a low-lying placenta, were examined by perineal scanning. In all these cases it was possible to compare the results with those of abdominal ultrasound examinations documented in the patient's records. The "perineal scan"-examinations were performed "blind", i.e., without knowledge of the results of prior abdominal ultrasound. Abdominal sonography was performed by a different examiner using the full-bladder-technique. Perineal scanning was done a short time after voiding. The results showed considerable and significant (p less than 0.001) discrepancies between the two methods; perineal scanning more often demonstrated higher grade diagnoses (27 patients, 32%) than vice versa (9 patients, 11%). These differences may be at least partially explained by the influence of bladder distension. Probably a full bladder produces false negative results more often than previously suspected. An analysis of pregnancy outcome yielded positive predictive values of 78% (abdominal ultrasound) and 86% (perineal scanning). Perineal scanning therefore seems to provide an uncomplicated and reliable means to verify an abdominal placenta localisation.

Cesarean Section↗
PubMed1991

[Slit drainage versus Redon drainage in a clinical comparison--initial experiences with a new kind of wound drainage system].

In a prospective, randomised study we compared the clinical properties of the established Redon drain with a new type of drain called "slit drain". Both types of drains were examined regarding the amount of drained fluid, the time elapsing until removal of the drain, the frequency of occlusion of the lumen as well as the patient's pain and the required force at extraction of the drain. The statistical analysis showed both drains to have equal abilities in draining of fluid if they were used under vacuum conditions. If used as nonsuction drains, the new device was able to drain more fluid than the established type of drain (p less than 0.05). Statistically relevant advantages of the slit drain were seen in a lower rate of obstruction of the lumen, a higher amount of drained fluid (as non-suction device) as well as an easier and less painful extraction.

Breast Neoplasms↗
PubMed1991

[The kinetocardiotocogram--initial clinical experiences using the kinetocardiotocogram].

160 woman patients in whom the course of pregnancy was uneventful or pathological (intrauterine growth retardation, percentile less than 5) were investigated at the Department of Obstetrics and Gynaecology of the University of Homburg/Saar between the 28th and 42nd week of pregnancy, using a newly developed cardiotocograph (HP M1350A Hewlett-Packard, Böblingen, FRG). By means of the kinetocardiotocogram (KCTG), fetal mobility (fetal movements of the whole body or of the extremities) was recorded simultaneously with the conventional recording of the fetal heart rate and uterine contractions. One of the aims in developing the KCTG was to record as far as possible all fetal movements synchronous to the recordings of heart rate and uterine contractions. To this end, the recording algorithm of the KCTG was adapted to the examination results obtained by two simultaneously operating ultrasound investigators. After the 28th week of pregnancy it was possible to record by the KCTG fetal "movement clusters" (combined body and limb movements) independent of the weight of the fetus and of amniotic fluid volume or positional anomalies, reliably and with good correlation with the results of the sonographic control investigations (r = 0.88-0.97). In cases of intrauterine growth retardation (percentile less than 5) a significantly reduced motility was observed on average as early as 13 days before delivery (p less than 0.005). It must be emphasized that, at this stage, most of the antenatal CTGs were normal. These findings indicate that KCTG can contribute to improved monitoring in high-risk pregnancies.

Cardiotocography↗
PubMed1991

[Pathologic Doppler flow findings and cardiotocography results].

Of 1950 pregnant patients (2870 Doppler ultrasound measurements) we observed, in a study group with highly abnormal Doppler-flow findings (n = 66, Feb. 1990), a correlation of Doppler flow and FHR-recordings. Among these 66 patients we retained 60 (91%) in the hospital. They had at least 2 FHR-recordings a day. The results of Doppler flow measurements in the fetal aorta and umbilical artery correlated well with diagnosis of IUGR. The comparison of the overall results of both fetal vessels did not indicate any significant difference. In 21% of all patients with highly abnormal Doppler flow findings, was no abnormal FHR record until delivery. 26% already showed an abnormal non-stress test before the first pathological Doppler assessment, in 44% abnormal FHR-recordings were observed later than the first abnormal Doppler flow finding in the course of pregnancy. The median interval was 13.5 days in cases with increased Doppler flow parameters but with detectable end-diastolic blood flow and was reduced to 8 days in cases with absent end-diastolic blood flow. In 9% of all cases, abnormal results were found with both methods on the same day. In 32% we observed a reproducible notch in Doppler flow velocimetry of uteroplacental vessels. The rate of congenital malformations was 14%. Thus abnormal Doppler flow signals can be estimated as "early" prognostic criterias for a compromised fetus at risk.

Birth Weight↗