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H Walter

Publications and source records attributed to H Walter.

At least 145 records · Page 8Linked to original sources
PubMed1992

Investigations on the variability of blood group polymorphisms among sixteen tribal populations from Orissa, Madhya Pradesh and Maharashtra, India.

Sixteen tribal populations from Orissa, Madhya Pradesh and Maharashtra have been typed for the polymorphic blood group systems A1A2B0, MNSs, Rhesus, Kell, Duffy and Diego. The heterogeneity in the distribution of haplotype and allele frequencies, respectively, is partly considerable. It is supposed that this is due to the operation of several microevolutionary factors, such as genetic drift, social and geographic isolation and gene flow. This is discussed in detail.

Alleles↗
PubMed1992

Investigations on the variability of four genetic serum protein markers in Poland.

198 unrelated male and female Poles from Ostrów Wielkopolski (Central Poland) and 228 unrelated male and female Kashubes from Kościerzyna (Northern Poland) have been typed for four polymorphic serum protein systems: HP, TF, GC, and PI. Phenotype and allele frequencies of all these four polymorphic systems are quite different between Poles and Kashubes. Comparisons with some other Central and East European population samples (Slovaks, Hungarians, Matyos, Gypsies) revealed a considerable genetic heterogeneity among them. Genetic distance analysis showed that Hungarians and Matyos as well as Poles and Slovaks are found in two subclusters, which are linked up to one cluster. Gypsies and especially Kashubes exhibit a distinct position from this cluster. This genetic distance pattern can be explained satisfactorily considering the ethnohistory of the population groups under study.

Blood Proteins↗
PubMed1992

Investigations on the variability of four genetic serum protein markers (HP; TF, GC and PI subtypes) in Italy.

14 population samples from various Italian regions with a total of 2.577 unrelated male and female individuals were typed for four polymorphic serum protein polymorphisms: HP, and TF, GC and PI subtypes. The regional distribution of the allele frequencies of these four polymorphisms shows a considerable heterogeneity, which is for the most part statistically significant, thus indicating an obvious genetic variability of the population of the Italian Peninsula.

Alleles↗
PubMed1991

Partitioning of cells in dextran-poly(ethylene glycol) aqueous phase systems. A study of settling time, vessel geometry and sedimentation effects on the efficiency of separation.

The effect of prolonged settling times (up to 2 h), in high- and low-phase columns, on the cell partition ratios measured and on the separability of cell populations was examined. With closely related cell populations, modelled by rat erythrocytes in which subpopulations of red blood cells of distinct age were labeled isotopically, it was found that partitioning proceeds over the entire time period examined as evidenced by the continuous change in relative specific activity of cells in the top phase as the partition ratio falls. In control cell sedimentation experiments in top phase there was almost no change in the quantity of cells present when vertical settling (i.e., high-phase columns) was used and no separation of specific subpopulations was found. In the horizontal settling mode the initially higher cell partition ratio, as compared to vertical settling, decreased to a greater extent with longer time intervals; a given purity of cells only being obtained at a lower partition ratio than in the vertical settling mode. Cell sedimentation in top phase was appreciable with time in the horizontal settling mode but did not result in a separation of cell subpopulations. The effect of relative cell partition ratios and sizes in high- and low-phase columns on the efficiency of separation was examined by use of rat or sheep 51Cr-labeled red cells mixed with an excess of human unlabeled erythrocytes. Rat and sheep red cells are appreciably smaller than human erythrocytes. Rat red cells have higher, and sheep red cells lower partition ratios than human erythrocytes. With vertical settling, over a 2-h period, there is no appreciable contribution to the change in relative specific activities by cell sedimentation. However, the more rapid sedimentation of the larger human red cells has, with time, a measurable effect on the relative specific activities obtained during cell partitioning when run in the horizontal mode: enhancing the rat-human and diminishing the sheep-human cell separations. Partitioning cells in high-phase columns is of advantage with respect to increasing separation efficiency and virtually eliminating the influence of other physical parameters (e.g., cell size). Since the cell partitioning process continues for long periods of time, yielding ever-lower partition ratios with increasing proportions of cells with higher P values, a time may be selected which balances desired relative cell purity and yield.

Animals↗
PubMed1991

Gm and Km allotypes in four Sardinian population samples.

Serum samples of 683 unrelated male and female individuals of four Sardinian population samples (Sassari, Nuoro, Oristano and Cagliari) were typed for G 1 m (1,2,3,17), G 3 m (5,6,10,11,13,14,15,16,21,26), and Km (1). Phenotype, haplotype (Gm), and allele frequencies (Km), respectively, show a remarkable variability between these four population samples. Comparisons with other Italian populations reveal the considerable genetic difference of the Sardinians, which is in particular caused by the presence of the haplotype Gm1,3;5,10,11,13,14,26 in them. This haplotype is quite uncommon in Europeans and may reflect gene flow from Eastern populations (Phoenicians?) who came to this island in ancient-history times.

Alleles↗
PubMed1991

Evaluation of the extent of the early Maillard-reaction in milk products by direct measurement of the Amadori-product lactuloselysine.

A new method for the evaluation of the extent of lysine modification caused by the Maillard reaction is presented, based on the direct determination of the Amadori product lactuloselysine plus unmodified lysine after complete enzymatic hydrolysis by ion-exchange chromatography. Using a simple mathematical relation, the amount of modified lysine in milk products can be estimated without knowledge of the initial lysine value before heating or storage.

Animals↗
PubMed1991

Induction of vascular injury by Pseudomonas aeruginosa cytotoxin in rabbit lungs is associated with the generation of different leukotrienes and hydroxyeicosatetraenoic acids.

Pseudomonas aeruginosa cytotoxin, a transmembrane pore-forming protein, causes an increase in pulmonary microvascular permeability with subsequent lung edema formation, possibly related to the induction of arachidonic acid (AA) lipoxygenase products. To investigate this, isolated rabbit lungs were perfused with cytotoxin-containing buffer (6.5 and 13 micrograms of toxin/ml). A severalfold increase in the capillary filtration coefficient was induced, both preceded and accompanied by a marked time- (15-60 min) and dose-dependent release of cysteinyl leukotrienes (LT), LTB4, and 5-, 12-, and 15-hydroxyeicosatetraenoic acids (HETEs) into the lung perfusate. In the bronchoalveolar lavage fluid, corresponding AA-derived products were detected; the total sum of HETEs surpassed that of cysteinyl LTs in this compartment. The lipoxygenase inhibitors AA861 (10 microM) and nordihydroguaiaretic acid (100 microM) and EGTA (5 mM) suppressed the intravascular and alveolar liberation of all 5-lipoxygenase-derived AA metabolites, paralleled by a marked reduction and retardation of microvascular permeability increase (AA861). It thus seems that Pseudomonas cytotoxin induces generation of LTs and HETEs in rabbit lungs that may contribute to the development of pulmonary microvascular injury evoked by this bacterial agent.

Animals↗
PubMed1991

Investigations on the ethnic variability of the ABO blood group polymorphism in Iran.

112 Iranian population samples with a total of 600954 individuals are analyzed concerning the ethnic variability of ABO allele frequencies. The genetic heterogeneity within and between these population samples is considerable. This heterogeneity is discussed with regard to the ethnohistory of Iran. The most striking ABO allele frequencies are observed in Assyrians, Armenians and Zoroastrians, which differ extremely from that of all the other hitherto studied ethnic groups of Iran. Obviously varying ABO allele frequencies are seen also in Yazdis as well as in Turkomans and Arabs living in Iran. And finally the Iranian Jews reveal clear frequency differences in comparison with all the other Iranian population groups. It can be assumed that the specific ABO allele frequencies found in the above mentioned ethnic groups are connected with their different geographical origin as well as with their marked endogamy.

ABO Blood-Group System↗
PubMed1990

On the relation between surface area and partitioning of particulates in two-polymer aqueous phase systems.

Partitioning in dextran-poly(ethylene glycol) aqueous two-phase systems is an established method for the separation of biomaterials. Size and surface properties are generally regarded as parameters which contribute to the determination of the materials' partition coefficients, K. While molecular weight or surface area can be one of the determinants of the K value of biomaterials in the size range of macromolecules to very small particulates (e.g. some viruses), partitioning liposomes of identical surface properties and different but distinct sizes indicate that surface areas greater than about 0.2 microns 2 do not affect the K value obtained. Analysis of available partitioning data of much larger particulates (i.e. cells) reveals that surface properties per unit area outweight surface area per se in determining the K value in non-charge-sensitive, charge-sensitive and biospecific affinity phase systems.

Animals↗
PubMed1990

Differential effect of pH on the density and volume of rat reticulocytes and erythrocytes. Relevance to their fractionation by centrifugation.

Rats were injected with 59Fe-ferrous citrate and bled thereafter at different times (16 h to 49 d). This gave rise to red cell populations in which cells corresponding in age to the time elapsed between injection and bleeding were labeled. The anticoagulant used was either acid-citrate-dextrose (ACD) with a pH adjusted to 7.3 or ACD (pH 5.1). Final pH of the collected blood was about 7.2-7.4 in the former case and 6.4-6.7 in the latter. Red cells were then centrifuged (5) and approximately 7-10% of the packed cells from the top and 7-10% from the bottom of the cell column collected. When reticulocytes are the predominant labeled red cell population, as in blood obtained for about 24 h after isotope injection, a fractionation of these cells and mature erythrocytes is in evidence only when blood is collected at the higher pH. Thus, at pH 7.2-7.4 ratios of specific radioactivities of cells in top fraction/cells in an unfractionated sample are about 3, whereas at pH 6.4-6.7, the analogous ratios are 1 or less. These differences in specific activity ratios, as a function of pH at collection, virtually disappear after about 4 d following isotope injection. The lower pH is known to increase the volume and decrease the density of mature red blood cells. The marked effect of pH on cellular fractionation could be correlated with the smaller change in rat reticulocyte density and volume in acid medium. At pH 6.4-6.7, the densities of mature erythrocytes and reticulocytes are so close that their physical separation by centrifugation is not feasible.

Animals↗
PubMed1990

Red-cell enzyme polymorphisms in the Reggio Calabria province (Italy).

Acid phosphatase (ACP1), adenosine deaminase (ADA), esterase D (ESD), glyoxalase 1 (GLO1), phosphogluconate dehydrogenase (PGD) and phosphoglucomutase 1 and 2 (PGM1 and PGM2) polymorphisms have been studied in the Reggio Calabria province (Southern Italy). The ACP1*A allele and ADA, GLO1, PGD and PGM1 systems have frequencies similar to those reported for Sicily and Southern Italy.

Acid Phosphatase↗
PubMed1990

A contribution to classification of hallucinations.

Proceeding from the hypothesis that auditory hallucinations in psychotic patients have another biological basis than hallucinations provoked by hypnotic suggestion in healthy persons, we performed a symptom-comparative study by means of 99mTc-HMPAO single photon emission computed tomography. The results confirm the importance of pathogenesis in symptom-oriented psychiatric research.

Adult↗
PubMed1990

[Population genetics of HLA polymorphism in blood donors of Bremen and Hannover].

501 blood donors from Bremen have been typed for HLA-ABC and -DR. The results are compared with HLA data obtained on 474 blood donors from Hannover. The gene frequencies do not differ significantly between these two population samples. Comparisons with population samples from Kiel, Hamburg, Essen, Frankfurt/M., Mainz, Mannheim, Freiburg/Br., Munich and Vienna did also not reveal any remarkable differences concerning the gene frequencies. Analysis of linkage disequilibrium of two-factor and three-factor haplotypes could show that the typical Caucasoid allele combination A1/B8 is not a constituent part of three-factor haplotype combinations. Between the population samples from Bremen and Hannover no marked differences in the distribution of two-factor and three-factor haplotype frequencies could be found.

Adult↗
PubMed1989

[Ketoacidosis in long-term therapy with insulin pumps. Incidence, causes, circumstances].

110 type I diabetic patients were treated with CSII from 1980 to the end of 1988 on a routine basis over a total of 337 patient years and a mean of 36.7 months per patient. 14 cases of severe diabetic ketoacidosis (DKA) were seen in 14 patients representing an accumulated incidence of one episode of DKA per 209 patients months. DKA occurred on an average of 25 months after start of CSII therapy. The main causes of DKA were undetected leakage of the infusion system in nine, infection in three and mismanagement of the pump in two cases. Technical or electronic failures could be excluded in each case. The lack of checking urine for ketones, the wrong feeling of safety after long-term successful pump treatment, and a concomitant psychological stress situation favoured the misjudgement of the clinical symptoms of ketosis and the delay of hospital admission.

Adolescent↗
PubMed1989

Analysis of density-fractionated rat red blood cells of different ages by partitioning in two-polymer aqueous phase systems.

Rats were injected with radioactive iron and bled at different times thereafter. This gave rise to cell populations in which the bulk of labeled cells corresponded in age to the time elapsed between injection and bleeding. Such cell populations were centrifuged and the 7-10% least dense and the 7-10% most dense cells subjected to counter-current distribution in a charge-sensitive two-polymer aqueous phase system which fractionates cells on the basis of surface properties. While it is known that there is a tendency for cell density to increase with cell age and that rat red cells of different ages have characteristic partition ratios, we were able, by applying partitioning analysis to density-separated cells, to gather data not obtainable by use of either method alone. These include: (1) the demonstration of two very young cell populations having different surface properties in the most dense fraction; (2) the finding that in the least dense layer labeled mature erythrocytes (at least those labeled 18 days and beyond) and unlabeled red cells have overlapping distribution curves which indicate that the label in the top fraction can represent young or early middle-aged but never old cells; and (3) the presence, as judged by surface properties, of some middle-aged red cells, in addition to old cells, in the most dense cell layer.

Animals↗
PubMed1989

[Drug therapy of delusional parasitosis. The importance of differential diagnosis for psychopharmacologic treatment of patients with delusional parasitosis].

In 34 patients suffering from delusional parasitosis the relevance of an accurate differential diagnosis with respect to pharmacological treatment was investigated. Under a psychopharmacological therapy of the delusion's additional psychiatric symptomatology in 17 patients (50%) a full remission and in other 5 patients an improvement of the delusional symptoms was observed. The unexpected high recovery-rate is explained by the fact that all of the patients with additional depression showed a reduction also of the delusional symptomatology after a treatment with antidepressants. In contrast to that, patients with organic brain syndromes underlying the delusions had a significant worse outcome, which seems to be caused by the considerable lack of effective psychopharmacological treatment of such states. The results indicate that an accurate psychiatric differential diagnosis is of great importance for the psychopharmacological therapy of patients suffering from delusional parasitosis. In this context the Viennese decision-tree for delusional syndromes is discussed.

Adult↗