Search PubMed⌕ Search

Biomedical subjects

W Schmidt

Publications and source records attributed to W Schmidt.

At least 91 records · Page 5Linked to original sources
PubMed2001

Hygroma colli cysticum: prenatal diagnosis and prognosis.

The objective of this study is to analyze the prenatal management and prognostic factors of hygroma colli cysticum by using cytogenetic tests and sonographic morphological features. All cases with hygroma colli cysticum diagnosed and managed at our Prenatal Diagnostics Unit between January 96 and September 2000 were analyzed. Sonographic morphological features were divided in two groups; nonseptated (n = 18) and septated (n = 12) hygroma colli cysticum lesions were compared with fetal karyotype results and pregnancy outcome data. Statistical analysis was performed by Chi-square test and statistical significance was defined as p <0.05. In 5 years, 30 cases with hygroma colli cysticum were identified. Cytogenetic results were obtained from 23 (76.7%) cases (four chorionic villus sampling and 19 amniocentesis). Chromosomal abnormalities were present in 13 cases (56.5%). The most common chromosomal abnormality was Turner Syndrome (four cases, 17.4%) and Trisomy 18 (four cases, 17.4%). Pregnancy outcome data were available for 29 patients. Those fetuses with septated hygroma colli cysticum tended to have a worse fetal outcome, without statistical significance (p >0.05), compared with the nonseptated hygroma colli cysticum cases (75 vs. 61.1%, respectively). Fetal hygroma colli cysticum, either septated or not, carries high risks of aneuploidies and adverse fetal outcome. Recommended management includes karyotyping and if parents decide to continue the pregnancy ultrasound scan at 20 to 22 weeks' gestation is necessary, for excluding associated anomalies. At birth, if the cystic hygroma persists, it should be noted that a respiratory difficulty can happen and a pediatrician should standby as a precaution.

Adult↗
PubMed2001

Prenatal diagnosis of translocation and a single pericentric inversion 9: the value of fetal ultrasound.

A total of 2741 high-risk pregnant mothers underwent invasive prenatal procedures, and in 94 of them (3.4%), fetal chromosomal or genetic anomalies were detected. In this study, we report on single pericentric inversions of chromosome 9 as well as translocations, which constituted 32% (30 of 94) and 16% (15 of 94) of all identified chromosomal or genetic abnormalities, respectively. In six fetuses of the 30 with an inversion of chromosome 9, ultrasound findings were abnormal and consisted of hydramnios, anhydramnios, hydroureter, hydronephrosis, encephalocele and prune belly syndrome, occurring singly or in combination. Among the 15 fetuses with chromosomal translocations, five had sonographic abnormalities. In conclusion, we found detailed ultrasound survey of fetuses with either translocations or inversions of chromosome 9 to be an additional source of useful information concerning fetal status that could be of value in genetic counselling of affected parents.

Journal Article↗
PubMed2001

Effects of dobutamine and dopexamine on hepatic micro- and macrocirculation during experimental endotoxemia: an intravital microscopic study in the rat.

OBJECTIVE: To test the effects of dobutamine and dopexamine on hepatic portal and sinusoidal blood flow in a model of normodynamic endotoxemia. DESIGN: Randomized, controlled trial. SETTING: Experimental laboratory. SUBJECTS: Male Wistar rats (250-350 g). INTERVENTIONS: A total of 40 male Wistar rats were randomized into four groups: a control group, which only received Ringer's solution; an endotoxin group, which received a continuous infusion of 2 mg/kg body weight (bw)/hr of endotoxin; a dobutamine group, which received endotoxin and a continuous infusion of dobutamine (3 microg/kg bw/min); and a dopexamine group, which received endotoxin and dopexamine (2 microg/kg bw/min). The experimental period was 120 min. MEASUREMENTS AND MAIN RESULTS: Mean arterial blood pressure (MAP), heart rate (HR), and cardiac output (CO) were detected. Portal blood flow was measured using an ultrasonic flow probe positioned around the portal vein, and sinusoidal blood flow was detected in the left liver lobe using intravital microscopy. All detected variables remained stable in the control group. In the endotoxin group, HR increased significantly and MAP decreased significantly from 111 +/- 10 mm Hg to 95 +/- 8 mm Hg at 120 mins, whereas CO remained unchanged. Both in the dobutamine and the dopexamine group HR increased and MAP decreased more than in the endotoxin group. CO increased in both groups significantly. Portal blood flow (23 +/- 4 mL/min to 16 +/- 3 mL/min) and sinusoidal blood flow (38.6 +/- 2.5 to 22.8 +/- 1.2 10(3) microm(3)/sec) decreased significantly in the endotoxin group. In the dobutamine and the dopexamine group portal and sinusoidal blood flow remained at baseline values. CONCLUSIONS: In our model of endotoxemia, dobutamine and dopexamine preserved systemic and hepatic blood flow. These preservations of hepatic blood flow during endotoxemia could portend beneficial effects but need to be studied further.

Adrenergic beta-Agonists↗
PubMed2001

Iron stress-induced changes in root epidermal cell fate are regulated independently from physiological responses to low iron availability.

Iron-overaccumulating mutants were investigated with respect to changes in epidermal cell patterning and root reductase activity in response to iron starvation. In all mutants under investigation, ferric chelate reductase activity was up-regulated both in the presence and absence of iron in the growth medium. The induction of transfer cells in the rhizodermis appeared to be iron regulated in the pea (Pisum sativum L. cv Dippes Gelbe Viktoria and cv Sparkle) mutants bronze and degenerated leaflets, but not in roots of the tomato (Lycopersicon esculentum Mill. cv Bonner Beste) mutant chloronerva, suggesting that in chloronerva iron cannot be recognized by putative sensor proteins. Experiments with split-root plants supports the hypothesis that Fe(III) chelate reductase is regulated by a shoot-borne signal molecule, communicating the iron status of the shoot to the roots. In contrast, the formation of transfer cells was dependent on the local concentration of iron, implying that this shoot signal does not affect their formation. Different repression curves of the two responses imply that the induction of transfer cells occurs after the enhancement of electron transfer across the plasma membrane rather than being causally linked. Similar to transfer cells, the formation of extra root hairs in the Arabidopsis mutant man1 was regulated by the iron concentration of the growth medium and was unaffected by interorgan signaling.

FMN Reductase↗
PubMed2001

Different pathways are involved in phosphate and iron stress-induced alterations of root epidermal cell development.

Low bioavailability of phosphorus (P) and iron (Fe) induces morphogenetic changes in roots that lead to a higher surface-to-volume ratio. In Arabidopsis, an enlargement in the absorptive surface area is achieved by an increase in the length and frequency of hairs in roots of Fe- and P-deficient plants. The extra root hairs are often located in positions that are occupied with non-hair cells under normal conditions, i.e. over a tangential wall of underlying cortical cells. An involvement of auxin and ethylene in root epidermis cell development of Fe- and P-deficient plants was inferred from phenotypical analysis of hormone-related Arabidopsis mutants and from the application of substances that interfere with either synthesis, transport, or perception of the hormones. Application of the ethylene precursor 1-aminocyclopropane-1-carboxylic acid or the auxin analog 2,4-D caused a marked increase in root hair density in plants of all growth types and confers a phenotype characteristic of ethylene-overproducing mutants. Hormone insensitivity and application of hormone antagonists inhibited the initiation of extranumerary root hairs induced by Fe deficiency, but did not counteract the formation of extra hairs in response to P deprivation. A model is presented summarizing putative pathways for alterations in root epidermal cell patterning induced by environmental stress.

2,4-Dichlorophenoxyacetic Acid↗
PubMed2001

Association between interleukin concentration in follicular fluid and intracytoplasmic sperm injection (ICSI) outcome.

PROBLEM: The aim of this study was to determine the presence and concentration of interleukin IL-6, IL-8, and granulocyte-macrophage-colony-stimulating factor (GM-CSF) in pre-ovulatory ovarian follicular fluid (FF) of patients undergoing controlled ovarian hyperstimulation for intracytoplasmic sperm injection (ICSI) therapy on one hand, and to find out whether these cytotokine concentrations could be used as a predictive parameter for ICSI outcome. DESIGN: The levels of IL-6, IL-8, and GM-CSF were measured from women that underwent ICSI therapy and the results were compared between the patients who became pregnant after IC

Adult↗
PubMed2001

Transient bilateral osteoporosis of the hip in pregnancy. A case report and review of the literature.

Osteoporosis of the hip is a rare complication of pregnancy, the diagnosis of which can only be determined by radiologic means. Differentiation between osteonecrosis and osteoporosis remains problematic in some cases. Magnetic resonance imaging was reported as useful for the diagnosis of osteoporosis. Treatment of osteoporosis of the hip in pregnancy should be conservative including physical therapy, restricted weight bearing and analgetic therapy. We report an unusual case of bilateral transient osteoporosis of the hip in pregnancy.

Adult↗
PubMed2001

Ligand-mediated protection against phage lysis as a positive selection strategy for the enrichment of epitopes displayed on the surface of E. coli cells.

We present a novel strategy, termed CISTEM, which allows direct in vivo screening of polypeptides displayed on the surface of E. coli cells by a combination of ligand-mediated protection and phage-mediated selection. The effectiveness of this new approach was demonstrated by displaying the T7.tag on the surface of E. coli as a fusion with the outer membrane protein A, the receptor for bacteriophage K3. A monoclonal T7.tag antibody was used as protective ligand for T7.tag-displaying cells and phage K3 for the elimination of unprotected cells. When populations of bacteria, containing between 6 to 10,000 cells displaying the T7.tag and approximately 10(8) cells displaying an unrelated OmpA fusion protein, were infected with phage K3, specific and antibody-dependent survival of T7.tag displaying cells was observed, yielding an enrichment factor of up to 10(7)-fold. The CISTEM technology was used to select sequences from a T7.tag-based, randomised library and the results were compared to those obtained from selection by MACS with the same library. Together, these results reveal a novel in vivo screening strategy in which an E. coli phage receptor is used as display plafform and selection is performed in suspension upon addition of a protective ligand and a bacteriophage. Extentions and modifications of the basic strategy should lead to novel applications for the identification of protein-ligand interactions.

Amino Acid Sequence↗
PubMed2001

Neonatal nucleated red blood cell counts: relationship to abnormal fetoplacental circulation detected by Doppler studies.

Increased neonatal nucleated red blood cell counts are thought to be related to intrauterine hypoxemia. We sought to determine the effect of increasing circulatory impairment in fetuses on the neonatal nucleated red blood cell count. One hundred thirty-four singleton pregnancies were included in the study and were allocated to 4 study groups according to Doppler findings. The systolic-to-diastolic ratios of the umbilical artery, fetal aorta, middle cerebral artery, and uterine arteries were recorded. Fetuses were assigned to the following groups on the basis of the last Doppler examination before delivery: group 1, normal systolic-to-diastolic ratios in the examined vessels; group 2, a systolic-to-diastolic ratio greater than 2 SD above the mean for gestational age in the umbilical artery or fetal aorta and no abnormal Doppler findings in the uterine arteries; group 3, systolic-to-diastolic ratios greater than 2 SD above the mean for gestational age in all examined vessels; and group 4, absence of end-diastolic velocity in the umbilical artery or fetal aorta and systolic-to-diastolic ratios greater than 2 SD above the mean for gestational age in the uterine arteries. A blood sample from the umbilical artery was obtained within 1 minute after birth, and nucleated red blood cells per 100 white blood cells were counted by light microscopy. Nucleated red blood cell counts were higher in fetuses in group 4 (median, 72.0; range, 9-720; P < .001) and group 3 (median, 38.4; range, 7-201; P < .001) than in fetuses in group 1 (median, 5.1; range, 0-20). Neonates in group 4 had significantly lower birth weights (P < .001), lower arterial and venous pH values (P < .05), and lower Apgar scores after 5 minutes (P < .01) as well as an increased likelihood of cesarean delivery because of fetal distress (P < .001). The number of fetuses in group 4 with a cord blood base deficit of less than -8 mmol/L was increased. Nucleated red blood cell counts were comparable in fetuses in group 2 (median, 5.4; range, 0-37) and group 1. In groups 1 to 3 no brain-sparing effect occurred, whereas in 15 of 21 cases in group 4 a brain-sparing effect was present. Multivariate analysis revealed that Doppler results of the umbilical artery, fetal aorta, and uterine arteries were independent determinants of neonatal nucleated red blood cell count. Increasing abnormalities seen on fetoplacental Doppler studies are associated with increasing numbers of nucleated red blood cells at birth. Given the known relationship between abnormal Doppler flow and intrauterine hypoxemia, the neonatal nucleated red blood cell count might become an additional valuable tool in the surveillance of growth-restricted fetuses.

Aorta↗
PubMed2001

The clinical significance of antenatal pathological Doppler findings in the fetal middle cerebral artery in cases with peripheral reduced diastolic doppler flow but no absence of end-diastolic flow in the umbilical artery or fetal aorta.

PURPOSE: The effects of antepartum pathological Doppler findings in the fetal middle cerebral artery in cases with simultaneously peripheral reduced diastolic Doppler flow on perinatal outcome and the odds ratio of perinatal risks were studied. METHODS: 214 patients were examined by color Doppler ultrasound in relationship to complications in gestation and labor and fetal outcome. One thousand and seventy Doppler flow measurements of the middle cerebral artery, the umbilical artery and the fetal aorta between 28 and 40 weeks of gestation were performed. Sensitivity and odds ratio of synchronous cerebral pathological and peripheral pathological Doppler blood flow with regard to the prediction of intrauterine growth retardation, rate of cesarean section, preterm delivery and newborn depression was calculated. In all Doppler measurements there were no cases with absence of end-diastolic flow. RESULTS: Preterm delivery rate and intrauterine growth retardation rate were significantly higher in cases of synchronous cerebral pathological and peripheral pathological Doppler blood flow as in cases of isolated reduced peripheral blood flow (p<0.001; odds ratio 13.2 and 16.6). CONCLUSION: Pregnancies with no absence of end-diastolic flow in the fetal aorta or umbilical artery, but with reduced diastolic flow in these vessels and simultaneous pathological Doppler findings in the fetal middle cerebral artery are high risk pregnancies, above all in respect to intrauterine growth retardation, preterm delivery and newborn depression. Surveillance of pregnant women should be performed in a perinatal centre.

Aorta↗
PubMed2001

Comparison between the quality and function of sperm after semen processing with two different methods.

AIM: To compare the recovery rate of morphologically normal and chromatin condensed spermatozoa from native semen samples using the SpermPrep filtration columns and Percoll gradient centrifugation and to determine the influence of the two processing techniques on fertilization and pregnancy rates in an IVF-ET program. METHODS: Sixteen semen samples obtained from patient's husband were included in this study. Each was divided into two aliquots. The first aliquot was processed with SpermPrep filtration columns and the second, Percoll gradient centrifugation. Smears were made before and after semen processing with both methods for the evaluation of chromatin condensation (chromomycine CMA3) as well as morphology (strict criteria) of spermatozoa. One hundred and seventy oocytes were retrieved from the patients and the oocytes from each patient were subdivided into two sets: one set was inseminated using spermatozoa processed with SpermPrep and the other inseminated after semen processing with Percoll gradient centrifugation. RESULTS: The Percoll method yielded a significantly higher percentage of chromatin condensed (90.8 +/- 6.5% vs 82.3 +/- 8.8%, P = 0.017) and morphologically normal spermatozoa (12.9 +/- 7.4% vs 6.9 +/- 4.8%, P = 0.001) in comparison to SpermPrep. Whereas, sperm count recovery rate was significantly higher after the use of SpermPrep than after the Percoll gradient centrifugation. The fertilization rate was similar between the two methods. CONCLUSION: Semen processing with Percoll should be recommended for intracytoplasmic sperm injection as the natural selection is bypassed and the SpermPrep technique could be recommended for IVF and IUI programs as the sperm concentration plays a more significant role in these procedures.

Centrifugation, Density Gradient↗
PubMed2001

Peripheral microcirculation during pregnancy and in women with pregnancy induced hypertension.

During pregnancy the cardiovascular system undergoes several changes so as to adapt the maternal organism to the strains of pregnancy. These adaptations can assume a pathological development in persons with a previous history of cardiovascular problems. On the other hand the absence of these adaptations may lead to a pathological course of pregnancy. Pregnancy induced hypertension (PIH) may be such a pathological development due to maladaptation. The causes are for the most part unknown. For some time it has been assumed that it is due to microcirculatory disorders. Using periungual capillary microscopy the present study prospectively investigated the changes in peripheral microcirculation during pregnancy focussing on pregnancy induced hypertension. Sixty-seven women with a normal course of pregnancy and 28 women with pregnancy induced hypertension were evaluated. Throughout the prospective study 3 examinations were performed during pregnancy and one during childbed. The women who developed a PIH were registered during the third trimester. Erythrocyte velocity at rest and vascular reagibility of capillaries following a 3 minute ischaemia were evaluated. In the course of pregnancy a significant increase of approximately 30% in erythrocyte velocity could be observed. Interpolation to obtain the best strait line result demonstrates that it is a continuous increase. Erythrocyte velocity returns to normal in the course of 14 weeks post partum. Due to a physiological vasodilatation during pregnancy, vascular reaction to ischaemic stress significantly decreases. During childbed these changes return to normal. Examinations on women with pregnancy induced hypertension not only showed a significant reduction of microcirculation under resting conditions but also a different pattern of reaction to ischaemic stress. Erythrocyte velocity under resting conditions lies 36% below normal values. Furthermore the distinctly shortened hyperaemic period indicates a hightened sensitivity to vasoconstrictive substances in women with PIH. While taking into account the clinical data a positive correlation with the severity of the illness was able to be established.

Adult↗
PubMed2001

The immunolocalization of Bcl-2 in human term placenta.

PURPOSE: To study the immunolocalization of the Bcl-2 protein in formalin-fixed placental tissue collected from uncomplicated term pregnancies. METHODS: A total of 19 human term placentas of 38-41 weeks' gestation, 11 obtained from spontaneous deliveries and eight from elective caesarean sections prior to labour were included. Sections were incubated with an antibody to the Bcl-2 protein and light microscopy was used to evaluate Bcl-2 staining. RESULTS: The anti-apoptotic Bcl-2 protein was expressed diffusely throughout the cytoplasm of the syncytiotrophoblast with much less intensive staining in cytotrophoblast and mesenchymal cells. Bcl-2 expression was reduced or lost in areas of syncytial sprouts. No differences in Bcl-2 staining were observed between placentas obtained after spontaneous deliveries and those collected before the onset of labour after elective caesarean section. CONCLUSION: Expression of the anti-apoptotic Bcl-2 protein in human term placenta does not seem to be influenced by parturition. Additionally, Bcl-2 expression might be an important factor in the regulation of apoptosis in the human trophoblast and thus in maintaining placental function during gestation.

Female↗
PubMed2001

Blood pressure stability in a normotensive population during intake of a monophasic oral contraceptive containing 20 microg ethinylestradiol and 75 g gestodene.

OBJECTIVES: Evaluation of the impact of a monophasic gestodene-based oral contraceptive on blood pressure in a population that was normotensive at baseline. METHODS: Data on blood pressure were retrospectively analyzed from four large prospective clinical phase III trials with an oral contraceptive containing 20 microg ethinylestradiol and 75 microg gestodene. A total of 1342 young fertile women were evaluated after 12 treatment cycles. RESULTS: The mean systolic and diastolic blood pressure did not change during treatment. Approximately 89% of women were normotensive at baseline and 93% at the end of the treatment period. Only a few women (< or = 1%) were hypertensive at baseline; an increase in this prevalence was not found after 12 cycles of oral contraceptive use. The number of women who experienced a blood pressure increase was almost identical to the number who experienced a decrease. Approximately 90% of women had either a negligible blood pressure change of maximal +/- 10 mmHg or a decrease. CONCLUSIONS: The findings of this retrospective analysis confirm that monophasic gestodene has a negligible effect on blood pressure in users who were normotensive before treatment began.

Adolescent↗
PubMed2001

[Kinetics and dosimetry of monoclonal antibody MAb-170: evaluation of possibilities for intraperitoneal radioimmunotherapy].

UNLABELLED: The monoclonal antibody MAb-170 is directed against adenocarcinomas of different origin. Recent experience in radioimmunoscintigraphy revealed a positive uptake of this MAb in peritoneal metastases of ovarian carcinoma (FIGO III/IV). AIM: The present investigation should clarify the question whether this antibody could be of use in an adjuvant intraperitoneal radioimmunotherapy (RIT) in patients with minimal residual disease after first-look surgery. METHODS: Four patients underwent intraperitoneal application of Tc-99m MAb-170. Subsequent quantitative whole-body scintigraphy, serum and urine sampling were performed for a 48 h period. In one case tumour tissue specimen were sampled during the first surgical procedure 15 h p.i.. RESULTS: The quantitative evaluation revealed no relevant accumulation in liver, spleen and bone marrow never exceeding 5% of the whole-body activity. The critical organs are the kidneys that showed 8 to 11% uptake at 24 h p.i.. The effective serum curve had a maximum at 24 h p.i., the second phase gave a elimination half-time of 53 h. Assuming the worst case, the mean dose to red bone marrow was 0.3 Gy/370 MBq injected dose (ID). CONCLUSION: These results confirm that a RIT with Re-186 MAb-170 is feasible with activities of up to 3.7 GBq. A kit for labelling MAb-170 with Perrhenate is under investigation.

Adenocarcinoma↗