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M Dobosz

Publications and source records attributed to M Dobosz.

At least 37 records · Page 2Linked to original sources
PubMed1994

Genetic variation at the ApoB 3'HVR, D2S44, and D7S21 loci in the Ewondo Ethnic Group of Cameroon.

A sample of the Ewondo population (a Bantu-speaking group of Southern Cameroon) was analyzed for the polymorphism at three tandem repeated DNA loci (ApoB 3' HVR, D2S44, and D7S21). We observed a greater number of ApoB 3' HVR alleles (17) and a significantly higher estimated heterozygosity (.879 +/- .011) than in previously surveyed populations, with the exception of U.S. Blacks. The higher genetic variability of Ewondo and U.S. Blacks was also shown by the ApoB 3' HVR allele-frequency spectra. A method for measuring population distances, based on cumulative fragment-size distribution, is described. Interpopulation comparisons for ApoB 3' HVR were carried out by this method and were compared with those obtained by a genetic distance measurement. The two sets of results showed a consistent pattern of population differentiation: the Ewondos and the U.S. Blacks clustered together and were well apart from both a Caucasian cluster (Swedes, U.S. Whites, Italians, and Germans) and other well-defined populations (Sikhs of India and Pehuence Indians of Chile). Profile distances were then computed from D2S44 and D7S21 bined data. This analysis indicated a genetic affinity between Ewondos, U.S. Blacks, and Afro-Caribbean Blacks and outlined the genetic diversity between Ewondos, Caucasians, and Asian Indians.

Africa South of the Sahara↗
PubMed1993

Distribution of alleles and genotypes from three hypervariable DNA loci in individuals from central and southern Italy.

Three hypervariable locus-specific DNA probes (D2S44, alpha globin 3'HVR, D12S11) used in the routine typing activities of our laboratory have been studied using a representative sample of individuals from central and southern Italy. We report allele and genotype distribution of these systems, and discuss several problems met when typing quasi-continuous arrays of restriction fragments.

Alleles↗
PubMed1993

The role of endoscopic thrombin injections in the treatment of gastroduodenal bleeding.

One hundred and ninety-one patients who had emergency endoscopy performed for acute gastroduodenal haemorrhage and were found to be bleeding actively (N = 141) or to have an ulcer containing a non-bleeding visible vessel (N = 50) were studied. Patients with active bleeding were divided into two groups: group I included 47 patients in whom diagnostic endoscopy was performed and conventional management applied; and group II contained 94 patients in whom, apart from conventional treatment, endoscopic thrombin injections could also be offered. Fifty patients with non-bleeding visible vessels were admitted to a prospective randomised trial and assigned to either endoscopic injections (group A, N = 25), or no primary endoscopic treatment (group B, N = 25). The introduction of the injection therapy in patients who were actively bleeding resulted in a significant reduction of the emergency operation rate (70.2% v. 12.8%; P < 0.001), mortality rate (21.3% v. 8.5%; P < 0.05 and blood transfusion requirements (4,220 +/- 1,840 ml v. 1,980 +/- 980 ml; P < 0.05). Endoscopic thrombin injections of non-bleeding visible vessels reduced the rebleeding rate (40% v. 4%; P < 0.01) and blood transfusions (2,939 +/- 1070 ml v. 1,390 +/- 552 ml; P < 0.05).

Female↗
PubMed1992

Errors in sizing bands of hypervariable DNA profiles on autoradiograms: are they Gaussian?

The accuracy of procedures for sizing hypervariable restriction fragments by Southern blot analysis (SBA) has been tested under three different experimental conditions: (i) intrablot serial analyses: three heterozygous DNA profiles were tested 14 times each in the same gel electrophoresis; (ii) intralaboratory analyses: we replicated three profiles (six autoradiographic bands) in over 100 SBA experiments; (iii) interlaboratory analyses: 15 serial measurements produced in a recent collaborative study (Forensic Sci. Int. 1991, 49, 1-15) were taken into account. In these three cases, a typical U-shaped correlation curve between molecular size and coefficient of variation was found. We explain decrease of accuracy at both extremities of the gels in terms of: (i) enlarged shapes of bands and mean electrophoretic resolution at the cathode; (ii) diffusion and blurring of bands at the anodal edge. The three populations of data were subjected to a chi 2 test and to the Kolmogorov-Smirnov test in order to verify their compliance with normal distribution. Twenty-three out of 27 tests indicated no significant deviation from the assumption of Gaussian distribution. We recommend the adoption of tests for normality to validate the use of symmetric confidence intervals for calculating gene frequencies and asserting a match between adjacent bands.

Analysis of Variance↗
PubMed1992

[Synthesis of 4,4-substituted-5,5-mercapto-3,3'-bi-1,2,4-triazole and 2,2'-amino-substituted-5,5-bi-1,3,4-thiodiazole].

In reaction of oxalic acid dihydrazide with isothiocyanates were obtained the respective thiosemicarbaside derivatives (Ia-IXa). Their cyclization in alkaline media have given the corresponding 4,4'-substituted-5,5'-mercapto-3,3'-bi-1,2,4-triazole (Ib-IXb), in acidic media however were formed the 2,2'-amino-substituted-5,5'-bi-1,3,4-thiodiazole (Ic-VIIIc).

Chemical Phenomena↗
PubMed1992

Studies on the products of conversion of 4-ethoxycarbonylmethyl-1,2,4-triazoline-5-thione. VII. Synthesis of 4-beta-acetylaminoethyl derivatives of 1,2,4-triazoline-5-thione.

In the reaction of 4-ethoxycarbonylmethyl-1,2,4-triazoline-5-thione derivatives (Ia,b) with the primary amines the corresponding amides (IIa,b-IVa,b) have been formed. These amides were then undergone to reduction with LiAlH4 leading to the formation of corresponding amines (Va,b-VIIa,b). Then by means of the reaction with acetic anhydride these amines were transformed into corresponding acetylamine derivatives of 1,2,4-triazoline-5-thione (VIIIa,b-Xa,b).

Acetic Anhydrides↗
PubMed1992

Synthetic antiproteases in acute pancreatitis: an experimental study.

Acute pancreatitis was induced in 19 anesthetized dogs by retrograde injection of bile mixed with trypsin into the pancreatic duct. Two groups, of six animals each, were treated with intravenous infusion of synthetic antiproteases: gabexate mesilate and nafamostat mesilate in doses of 1 mg/kg per hr. One group of seven animals remained untreated. Two untreated dogs died during the experiment. All the treated dogs survived. Hemodynamic data were monitored hourly during a 6-hr observation period. In the untreated animals, cardiac output, mean arterial pressure, and left ventricular stroke volume decreased rapidly; an increase of pulmonary vascular resistance and systemic vascular resistance was observed. Synthetic antiproteases, given as a therapy, improved the hemodynamic parameters significantly and prevented the animals from developing shock. Gabexate mesilate and nafamostat mesilate seem to be of value in the treatment of experimentally produced acute pancreatitis in dogs.

Acute Disease↗
PubMed1991

Efficient, small scale electroelution of high molecular weight DNA from agarose gels by a miniature vertical electrophoresis cell.

A miniature, vertical electrophoretic system is described that allows quick elution and efficient harvesting of double-stranded, high molecular weight DNA fragments from agarose gels. A gel slice containing the band of interest is excised from the agarose gel after submarine electrophoresis and placed into an electrophoresis cell, assembled by inserting a truncated micropipette tip into a 2.0 mL polypropylene tube. The tip supports the agarose slice and is connected to dialysis tubing. Platinum wire electrodes are placed over the tip and at the bottom of the test tube. DNA molecules are quickly eluted into the dialysis bag (60 s to 10 min for bands ranging from 2 to 23 kb) and then easily recovered. The method is highly efficient and allows considerable time saving. Of special interest is its applicability to small starting amounts of DNA (less than 0.5 micrograms per band). Purity of the DNA is comparable, if higher, to that obtainable by conventional electroelution on dialysis bags and DEAE-cellulose membrane electrophoresis. The system is simple enough to be used as a routine method for eluting multiple bands in short times.

Bacteriophage lambda↗
PubMed1991

Estimating allele frequencies of hypervariable DNA systems.

Several polymorphisms of human DNA have been shown to be hypervariable due to the recurrence of a variable number of tandem repeats (VNTRs) in the lengths of allelic restriction fragments. The recurrence of allelic variants in this novel class of polymorphisms seems to comply well with a model of continuous random variables. Based on this assumption, we have compiled some simple algorithms for classification of continuous data and estimation of classes of relative frequencies and have implemented these routines for the management of databases storing hypervariable single locus DNA genetic systems. The algorithms are compiled in BASIC language and can be incorporated in task-oriented computer programs. Three procedures are discussed, based in turn on: (a) using predetermined, arbitrary classes; (b) point estimations of frequencies for single fragments using error measurements associated with the kilobase value assignment; (c) estimates of phenotype frequencies according to error measurements. Error measurements are obtained from a statistic of values pertaining to several restriction fragments (genomic controls) repeatedly tested in different experiments. Problems related to these approaches are discussed.

Algorithms↗
PubMed1991

Beneficial effect of therapeutic infusion of nafamostat mesilate (FUT-175) on hemodynamics in experimental acute pancreatitis.

Acute pancreatitis was induced in 13 anesthetized dogs by retrograde injection of bile mixed with trypsin into the pancreatic duct. Six animals were treated with intravenous infusion of new synthetic antiprotease. Nafamostat Mesilate, at a dose of 1 mg/kg/h. Four out of seven untreated animals died during the experiment. All the treated dogs survived. Hemodynamic data were regularly monitored during a ten-hour observation period. Cardiac output, mean arterial pressure and left ventricular stroke volume decreased rapidly in the untreated animals. An increase in systemic vascular resistance and pulmonary vascular resistance was observed in dogs without treatment. Nafamostat Mesilate given as therapy significantly improved the hemodynamic parameters, and prevented the animals from developing shock. The study demonstrates an advantageous influence of synthetic antiprotease Nafamostat Mesilate on the course of acute experimental pancreatitis.

Acute Disease↗
PubMed1989

Effect on hemodynamics of therapeutic infusion of gabexate mesilate (FOY) in experimental acute pancreatitis.

Acute pancreatitis was induced in ten anesthetized dogs by retrograde injection for bile mixed with trypsin into the pancreatic duct. Five animals were treated with i.v. infusion of gabexate mesilate in a dose of 1 mg/kg per hour. Hemodynamic data were regulary monitored during a 10-h observation period. Cardiac output (CO), mean arterial pressure (MAP), and left ventricular stroke volume (LVSV) decreased rapidly in untreated animals. An increase of systemic vascular resistance (SVR) and pulmonary vascular resistance (PVR) was observed in dogs without treatment. Gabexate mesilate given as a therapy significantly improved the hemodynamic parameters. The study demonstrates an advantageous influence of synthetic antiprotease gabexate mesilate on the course of acute experimental pancreatitis.

Acute Disease↗
PubMed1988

Characterization of genetic variants of human serum transferrin by isoelectric focusing: comparison between conventional and immobilized pH gradients, and application to a protocol for paternity testing.

The polymorphism of transferrin (Tf) is currently being studied by isoelectric focusing in carrier ampholyte-generated pH gradients, carrier ampholyte-separator pH gradients or in immobilized pH gradients. Details for obtaining reproducible results with each of the three procedures are outlined. The effectiveness of pretreatment of serum samples with ferrous/ferric salts is discussed, and incubation times optimized after spectrophotometric measurement of the monoferric Tf conversion. Most of the presently available commercial batches of carrier ampholytes do not reliably discriminate the six common TfC subtypes. Resolution of C1, C3 and C2 was achieved by adding 20 to 90 mM HEPES slab gels prepared with various carrier ampholytes. Isoelectric focusing in carrier ampholyte-separator pH gradients cannot be recommended as a standard typing procedure because the results strongly depend on the batch of carrier ampholytes. Tf subtype resolution was only achieved by using isoelectric focusing in immobilized pH gradients with pH slopes reliably reproducible from one experiment to another. Two major shortcomings of immobilized pH gradients are a marked tendency to protein precipitation at the application site and an interaction of proteins with the charged matrix. A protocol for Tf subtyping in immobilized pH gradients is described, based on prior desialylation of samples instead of pretreatment with iron. Sample entry into the matrix was optimized by addition of 5 mM Tris to the gels, and initially running them at low voltage. Recommendations are provided for the application of Tf typing for paternity testing.

Genetic Variation↗
PubMed1988

Immobilized pH gradients in ultrathin-layer (100 micron) gels: avoiding capillarity by a 'squeezing-sealing mold' technique.

Several procedures for casting 100 microns ultrathin immobilized pH gradients are described. When acrylate/glass molding cassettes (Pascali et al., Electrophoresis 1987, 8, 371-373) are used two main problems are encountered: (i) a tendency of polymerization solutions, at the beginning of delivery, to spread across the glass surfaces with troublesome effects on the gradient stratification, and (ii) the raising of steep menisci at both extremities of the pH intervals, originating from capillarity phenomena and resulting in nonuniform gradients with bowed electrophoretic patterns. The first shortcoming was acceptably solved by increasing the density of sucrose gradients, and pouring them into prewarmed molding cassettes. The detrimental effect of menisci could be overcome by using a 'squeezing-sealing mold' technique. A molding cassette was endowed with a continuous, squared spacer frame, the upper side being open by inserting a wedged clip. A slight excess of polymerization solution was first dispensed into the cassette and squeezed away on removal of the clip. By completely excluding air from the molding cassette, uniform and well reproducible ultrathin gels could be cast. A major advantage of ultrathin immobilized pH gradient gels is the drastically shorter focusing time.

Blood Proteins↗
PubMed1988

Determination of neutral haemoglobin variants by immobilized pH gradient, reversed-phase high-performance liquid chromatography and fast-atom bombardment mass spectrometry: the case of a Hb Torino alpha 43 (CE1) Phe----Val.

A neutral haemoglobin variant was identified by the combined use of different analytical methods. Isoelectric focusing on immobilized pH gradients (under denaturing conditions) allowed to detect and alpha chain variant. HPLC of tryptic digest showed that its amino-acid variation resided on T alpha 6 peptide (position 41-56). In the fast-atom bombardment (FAB) positive mass spectrum of the tryptic digest, the protonated molecular ion of the T alpha 6 peptide occurred 48 mass units lower than the normal T alpha 6 fragment, corresponding to a Phe----Val substitution. To a partial sequence determination (aminopeptidase digestion of the T alpha 6 peptide, followed by amino acid determination and FAB-MS analysis of the digestion-generated mixture) the substitution appeared to be on Phe43 (CE1). This variant is already known as Hb Torino. The procedure here described proved to be fast and simple, and feasible whenever neutral variants are supposed to occur.

Child, Preschool↗
PubMed1987

Unusual transferrin TF*D mutants in some Congo populations.

Transferrin allele (TF) distribution was investigated in three Bantu and one Babenga Pygmy groups of Congo, by isoelectric focusing on polyacrylamide (PIEF). In comparison with other Black populations, the four groups had a twofold higher TF*D frequency. Three different TF*D mutants were observed, the commonest type of which was identical by PIEF to a *D1 Caucasian allele. The classification of the other two is discussed. The homozygous TF D1 pattern was present in Babenga. The polymorphism of transferrin confirmed the uniqueness of anthropological traits in such Congo populations.

Alleles↗