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W Schnedl

Publications and source records attributed to W Schnedl.

At least 19 recordsLinked to original sources
PubMed1997

Comparative evaluation of three assay systems for automated determination of hemoglobin A1c.

We evaluated three newly introduced systems for automated determinations of hemoglobin (Hb) A1c, which allow the processing of large amounts of samples in a routine clinical laboratory. We compared these methods--the Variant HPLC, the Hi-Auto A1c analyzer system, and the Roche immunoassay--with the Diamat HPLC system. All showed good precision and good concordance with the Diamat HPLC. The reference range for Hb A1c has to be determined by the laboratory for each assay system. Interference study showed no statistically significant influence of anemia, polycythemia, rheumatoid factor, or chronic hemodialysis, although individual Hb A1c values can be influenced by polycythemia (when measured with the Hi-Auto A1c analyzer) and by chronic hemodialysis (when measured with the Variant HPLC). HPLC was not suitable for measuring Hb A1c in the examined cases of hemoglobin variants; assaying fructosamine seems to be better for monitoring these patients.

Anemia↗
PubMed1996

Sonographically-guided extracorporeal shockwave lithotripsy for pancreatic stones in patients with chronic pancreatitis.

Over a 2 year period, 10 patients with pancreatic stones due to alcohol induced chronic pancreatitis (proven by endoscopic retrograde pancreatography) underwent extracorporeal shockwave lithotripsy. Prior to shockwave therapy, all patients underwent endoscopic sphincterotomy. Targeting of shockwave lithotripsy was exclusively performed under sonographic control. All patients were treated with a second generation electrohydraulic spark gap lithotriptor and fragmentation of concrements could be achieved in all cases. Complete duct clearance was confirmed in seven patients by endoscopic retrograde pancreatography in one session, with endoscopic fragment extraction by basket and/or balloon catheter. In three patients, balloon dilation of concomitant strictures located in the head of the pancreas was performed prior to fragment extraction. All stone-free patients showed no further symptoms over the follow-up period of 12 months. Three patients in whom complete extraction of fragments was not successful experienced minor symptoms over the 12 month follow-up period.

Adult↗
PubMed1993

A simple scintigraphic method for continuous monitoring of gastric emptying.

A new and simple scintigraphic method for the measurement of gastric emptying was developed and validated. The test meal consists of 200 g potato mash mixed with 0.5 g Dowex 2X8 particles (mesh 20-50) labelled with 37 MBq (1 mCi) technetium-99m. After ingestion of the meal, sequential dynamic 15-s anteroposterior exposures in the supine position are obtained for 90 min. A second recording sequence of 20 min is added after a 30-min interval. The results can be displayed as immediate cine-replay, as time-activity diagrams and/or as activity retention values. Complicated mathematical fittings are not necessary. The method lends itself equally to the testing of in- and outpatients.

Anion Exchange Resins↗
PubMed1992

Hb Graz or alpha 2 beta 2(2)(NA2)His-->Leu; a new beta chain variant observed in four families from southern Austria.

Two abnormal hemoglobins were accidentally detected by cation exchange high performance liquid chromatography with the Diamat system of Bio-Rad Laboratories; the variants eluted together with the fast-moving Hb A1c. Structural analysis of isolated beta chains and sequence analysis of amplified DNA identified a new variant, i.e. Hb Graz that has a His-->Leu replacement at position 2 of the beta chain, in four healthy, apparently unrelated, adults. The second variant was identical to Hb Sherwood Forest or alpha 2 beta 2(104)(G6)Arg-->Thr; it is believed that this may be the second observation of this abnormal hemoglobin.

Amino Acid Sequence↗
PubMed1991

[The diagnostic potential of amniocentesis in the first 12 weeks of pregnancy].

Prenatal diagnosis of chromosomal and biochemical defects is accepted as a routine in high-risk patients. To eliminate the disadvantages of traditional amniocentesis (late diagnosis) and of chorion villus sampling (placentar mosaics, higher fetal loss rate) we evaluated the facts on amniocentesis during the first 12 weeks of pregnancy. 42 samples were analysed. 21 amniotic fluid samples were from pregnancies before the 13th week of gestation, 21 further punctures were performed between the 13th to 15th week and served as comparative figures. Of 21 samples, diagnosis was possible in 16 cases. Four cultures did not show any growth of cells; in one case, amniotic fluid could not be aspirated. In the comparison group chromosomal diagnosis could be done in every case. An average of 12.3 ml of amniotic fluid were taken. Chromosomal disorders found, included a translocation in chromosome 13/14 as well as a trisomy of chromosome 18. Biochemical defects such as Gaucher's disease and Niemann-Pick disease were excluded. 30 pregnancies without pathological symptoms were seen (mean birth weight 3200 g, mean duration of pregnancy 39 weeks). One case of abortion following amniocentesis was found in the 16th week of gestation. One case of premature delivery occurred in the 34th week and the pregnancy of a 40-year old women was complicated by EPH gestosis while 9 pregnancies were terminated by interruption following the patients' wish. Because chromosomal diagnosis could not be performed in five of 21 cases, amniocentesis during the 13th week of gestation cannot be recommended as a routine method. Early amniocentesis, however, is an alternative to the traditional amniocentesis at the 16th week of gestation.

Abortion, Spontaneous↗
PubMed1991

[DNA analysis and prenatal diagnosis in cystic fibrosis].

Cystic fibrosis (CF) is the most common autosomal recessive lethal genetic disorder in man, affecting 1 in 2,000 live births. The carrier frequency in Caucasians is 1 in 20. Approximately 70 per cent of the mutations correspond to a specific deletion on chromosome 7 (region 7q31). This delta F 508 mutation of the CF gene results in the loss of phenylalanine at position 508 in the gene product. About 50 per cent of the individuals with CF are homozygous for this deletion and suffer from pancreatic insufficiency. The remaining half are mostly compound heterozygotes between this deletion and another mutation. They exhibit less severe symptoms. Several simple polymerase chain reaction (PCR) tests are available to detect the delta F 508 mutation, allowing rapid prenatal diagnosis of the disease. In those families where other mutations of the CF gene are involved prenatal diagnosis is performed by means of tightly linked restriction fragment length polymorphisms (RFLPs). PCR tests are available for RFLP analysis too. Testing for the delta F 508 deletion, present in about 3 per cent of the normal population, may prove invaluable for extensive carrier screening. Thus, half of the couples at risk could be recognized before the first affected child is born.

Amino Acid Sequence↗
PubMed1988

Abortion risk in chorionic villus sampling. Evaluation in elective termination of pregnancy.

100 patients were examined to evaluate the risk of abortion of chorionic villus sampling. In the 8th-10th week of pregnancy a catheter with a mandrin was introduced into the chorion frondosum under ultrasound guidance. The mandrin was then removed and trophoblast tissue obtained by aspiration. The patients agreed to postpone elective termination of pregnancy for 2 weeks. Another ultrasound was performed before suction curettage. With increasing experience, the abortion rate dropped to 4%, whereas the rate of successful biopsies and analyses rose to more than 90%. Based on these results, chorionic villi sampling was made available at the 1st Department of Obstetrics and Gynecology, University of Vienna, as an alternative method to amniocentesis. Out of 38 biopsies, 25 karyotypes were normal, two biopsies revealed pathological results (trisomy 21, 22), 11 samples showed no results (insufficient tissue or no mitoses). One patient had a spontaneous abortion (trisomy 22) and one an abortion due to infection. Chorionic villus sampling could replace amniocentesis because chromosomal anomalies may be detected already in the 1st trimester of pregnancy.

Abortion, Induced↗
PubMed1986

[Value of chorionic biopsy in routine clinical diagnosis].

To test the advantages and risks of chorionic villi sampling, a method still new in prenatal diagnosis, 100 patients were examined. Most of the biopsies were taken in the 8th week of pregnancy. A soft catheter with a flexible mandrin was introduced transcervically to the chorion frondosum guided by ultrasound. The mandrin was then removed and trophoblastic tissue obtained by aspiration. The risk of abortion within 10-14 days after biopsy could be reduced to 4%. In the last series of chorionic villi samplings 92% of these could be evaluated cytogenetically. The use of quinacrine fluorescence technique showed that female mitoses were never found in male tissue. Because of the relatively low risk of abortion and the high diagnostic accuracy achieved in a very short period of time chorionic villi sampling can be considered as an alternative to amniocentesis.

Abortion, Spontaneous↗
PubMed1985

Gene localisation of the PGM1 enzyme system and the Duffy blood groups on chromosome No. 1 by means of a new fragile site at 1p31.

During routine paternity testing an apparent maternal exclusion was suggested by the PGM1 enzyme system (mother PGM1 1, child PGM1 2) and by the Duffy system (mother Fy(a-b+), child Fy(a+b-]. To clarify these findings chromosomal analyses and anthropological investigations were carried out. The possibility that the child had been mistakenly identified after birth could be eliminated. Chromosome analysis of the child showed a fragile site on one chromosome No. 1 at 1p31, a position supposed to carry the PGM1 and the Duffy loci. Although the father of the child is unknown, paternal origin of the fragile site is unlikely on account of the coincidence of the structural aberration with the missing expression of the maternal PGM1 and Duffy alleles thought to be located at the chromosome region involved. Thus localisation of the PGM1 and Duffy loci on 1p31 seems to have been achieved in an unusual way. The two loci appear to be closely linked.

Alleles↗
PubMed1984

Malignant histiocytosis with unusual features. Disseminated intravascular coagulation with severe hyperfibrinolysis, acute polyneuroradiculitis Guillain-Barré, and a unique chromosome abnormality.

The case of a 25-year-old man with the characteristic features of malignant histiocytosis (proliferation of abnormal histiocytic cells with erythrophagocytosis, hepatosplenomegaly, increased serum acid phosphatase, hypercalcemia, and bone pain) is reported. Chromosome studies revealed a near tetraploid karyotype with a pair of marker chromosomes. A few hours after initiation of chemotherapy with cyclophosphamide, Adriamycin (doxorubicin), vincristine, and prednisolone (CHOP regimen), the patient developed an acute ascending paralysis. Cerebrospinal fluid (CSF) findings were consistent with a diagnosis of Guillain-Barré Syndrome. On the next day, disseminated intravascular coagulation (DIC) with severe hyperfibrinolysis occurred. After intensive chemotherapy, complete remission could be achieved.

Adult↗
PubMed1982

[New staining methods for chromosome analysis (author's transl)].

The new fluorescent dye D 287/170 selectively stains human heterochromatin in chromosomes 9, 15 and Y. By using the DA-DAPI method the secondary constrictions of chromosomes 1 and 16 are additionally brilliantly stained. Various AT-specific dyes, such as quinacrine mustard or DAPI, show different staining behaviour in these heterochromatic segments. The most likely cause for these diverse results may be found not only in differences in DNA base frequency, but also in base sequence binding of fluorochrome to DNA. The D 287/170 method may prove useful in a variety of investigations such as, for instance, chromosome studies in malignant cells, hybridomas, evolutionary studies and in patients with problematic chromosome aberrations.

Fluorescent Dyes↗
PubMed1982

Chromosome abnormalities in 150 couples with multiple spontaneous abortions.

One hundred fifty consecutive couples with recurrent abortions with or without fetal deaths, malformations, or healthy infants were evaluated cytogenetically with a G-band method. Seven couples (4.7%) showed a chromosome aberration in one partner (5 translocations, 1 inversion, and 1 gonosomal mosaicism). Of the couples with a pure abortion history, 2.9% had a chromosomal abnormality. A high incidence of chromosomal rearrangements in the groups of couples with abortions plus fetal deaths or malformations was found. In contrast to other reports, a high incidence of cytogenetic abnormalities was also found in couples with abortions and healthy infants. Chromosome analysis is advocated as a primary tool in the evaluation of couples with repetitive fetal wastage.

Abortion, Habitual↗