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Biomedical subjects

K Richter

Publications and source records attributed to K Richter.

At least 253 records · Page 14Linked to original sources
PubMed1988

Establishment of a typing system for group D streptococci.

Group D streptococci (n = 971, 4037 samples, 139 patients) were isolated from two intensive care units. Differentiation and typing revealed 6 species, 25 phage types, and 85 enterococcinotypes. Distribution of species showed strong differences especially concerning Enterococcus faecium which was rarely isolated from extraintestinal sites (5.9%). Phage typing was species specific and discriminated Enterococcus faecalis (n = 703 typable isolates, 19 phage types) and the other group D streptococci (n = 63 typable isolates, 6 phage types). Based on the production of enterococcines (15 indicator strains used) the isolates could be classified into 6 groups, one of which was further subdivided into 3 subgroups. Enterococcus faecalis ssp. liquefaciens (n = 618), phage type V6b (n = 596), and enterococcine group IVc (n = 568) were most common. The combined use of markers resulted in 187 combinations, which demonstrated the valuable properties of the system.

Bacteriocins↗
PubMed1988

[Surgical anatomy of the bladder neck sphincter and its significance for vaginal surgery of stress incontinence].

The bladder closure mechanism works under the influence of a hydro-aerodynamic force that presses downward ("stress"). This "stress" is caused by the relative weakness of the pelvic floor. The structures running through the urogenital hiatus are compressed by the rectococcygeal and pubo-coccygeal muscles, which close the hiatus. The urogenital diaphragm bridges the slit in the levator ani muscles. It is made of the perineal membrane, the superior fascia, and the smooth and striated muscle lying between the two (M. sphincter urethrovaginalis, M. compressor urethrae). The superior fascia is an extension of the intraabdominal interior parietal fascia. The intraabdominal pressure stabilises the position of the urethrovesical region by pressing the intraabdominal contents and the subperitoneal connective tissue etc. closely together. The visceral fascia, the pubourethral ligaments, and above all, the connection to the superior fascia of the pelvis diaphragm anchor and regulate the paraurethro-vaginal region. The decompensation of this stress mechanism, usually caused by previous birth injury, leads to varied degrees of prolapse and incontinence. A rational therapy is the reconstruction of the damaged structures of the pelvis floor (diaphragma urogenitale, diaphragma pelvis, perineum etc.) in a complete individualised vaginal surgical reconstruction ("diaphragm repair"). This procedure makes a direct visualisation of the local situation and a control of the indication for surgery possible. If the suspensory apparatus is well anchored to the pelvis wall, reconstruction can be achieved. If this is not the case, a more sophisticated repair is necessary. If the indication is not correct and the limits of this method are ignored, or, if surgery is technically inadequate, this method will fall into disrepute.

Female↗
PubMed1988

[Rare vascular findings in CT of the upper mediastinum].

The CT findings of malformation of major veins near the heart are described (one case of persistent left superior vena cava and two cases of partial anomalous pulmonary veins) as well as one malformation of the pulmonary artery (vascular sling). These findings demonstrate the vascular character of the lesion and the procedure permits detailed clarification of the abnormality.

Adult↗
PubMed1988

Gene expression in the embryonic nervous system of Xenopus laevis.

Development of the nervous system in the amphibian embryo is initiated during gastrulation by an inductive interaction between chordamesoderm and dorsal ectoderm. The induced ectoderm forms the neural plate while uninduced ectoderm generates epidermis. We screened for genes activated during gastrulation and expressed specifically in the nervous system of Xenopus laevis in the expectation that clones representing such genes will constitute useful markers for the study of early neurogenesis. Probes were prepared from adult brain RNA by subtraction with RNA from ovary and from different combinations of adult kidney, muscle, and skin; cDNA libraries prepared from early to late neurula embryo RNA were screened with these probes. Six clones were chosen for further study. Three of these clones are not represented in the maternal RNA population but are activated at the late gastrula stage; the other three increase from a maternal base. Expression of five of the genes is restricted to the neural plate during embryogenesis, and all six are restricted to the central nervous system in premetamorphic tadpoles and adults. One of the clones encodes an apparently neurospecific isoform of beta-tubulin; the identity of the other clones is unknown. Expression of all six genes is suppressed in axis-deficient embryos that lack dorsal structures including the brain.

Animals↗
PubMed1988

Xenopus endo B is a keratin preferentially expressed in the embryonic notochord.

Screening of a cDNA library from neurula stage Xenopus laevis for notochord-specific sequences led to the isolation of a cDNA clone, XK endo B (Xenopus keratin endo B), which encodes a nonepidermal type I keratin. In situ and Northern blot hybridizations indicate that expression of XK endo B RNA is concentrated in the notochord, whereas expression in the endoderm is 5-10 times lower. XK endo B mRNA is present in the oocyte and increases from late gastrula. Accumulation peaks by late neurula and is greatly reduced by the tadpole stage; in the adult, a low level of XK endo B RNA is present in the liver. XK endo B shows sequence homology to mouse endo B; genomic Southern blots show that XK endo B is the most similar sequence to mouse endo B in the Xenopus genome, and vice versa, indicating that XK endo B and mouse endo B are homologs. The use of endo B as a marker and the germ layer derivation of the notochord are discussed in light of these results.

Amino Acid Sequence↗
PubMed1988

Effect of voluntary intake of iodinated salt on prevalence of goitre in children.

The availability of iodinated salt containing 20 mg of iodine as iodate/kg salt consumed on a voluntary basis enabled us to investigate its effect on goitre prevalence and iodine excretion in urine in a longitudinal, prospective, randomized study over 4 years. With this salt, under the assumption of a consumption of 5 g salt per day and person, an additional intake of 100 micrograms of iodine can be achieved. The study was performed on initially 334 children (168 boys, 166 girls) at the age of 10 years living in an area of iodine deficiency. After 4 years, 286 children still participated in the study. Initially, goitre prevalence as assessed by palpation was found to be 30.5% (37.4% in girls and 23.8% in boys). Neck circumference was found to be significantly higher in children with goitre compared with those without (30.2 +/- 1.4 vs 29.4 +/- 1.4 cm; P less than 0.001). Iodine excretion in the urine was significantly lower in children with goitre compared with those without (40.4 +/- 16.7 micrograms/g creatinine vs 46.1 +/- 24.9 micrograms/g creatinine; x +/- SD; P less than 0.05). The children were randomly assigned to two different groups: group A (N = 146) was asked to use iodinated salt, group B (N = 188) non-iodinated salt. Over the 4 years, a continuous increase in iodine excretion in urine could be demonstrated in group A.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1988

Union patterns and children's living arrangements in Latin America.

This article analyzes how union patterns in Mexico and Colombia affect the lives of children. The proportion of children affected by a disruption by the age of 15 is estimated by using life table methods. The factors that contribute to a child's risk of experiencing a disruption are investigated by using proportional hazard models. Finally, the living arrangements of children by the mother's marital status, the urban status, and the mother's educational attainment are explored. The findings indicate that about one-fifth of Mexican children and one-third of Colombian children spend some time with an unmarried mother by the age of 15. In addition, those who experience a disruption or are born outside of a union spend a considerable length of time in the single-parent state. Most children of an unmarried mother live in an extended-family household, often with a grandparent.

Adolescent↗
PubMed1988

[Reduction of cerebral hemorrhage and respiratory distress syndrome in premature infants by avoiding perinatal asphyxia].

Intra- and periventricular haemorrhage (IVH/PVH) and, under certain conditions, the respiratory distress syndrome (RDS) seem to be typical sequelae of perinatal asphyxia in preterm born infants. Therefore, an association of IVH/PVH and RDS can be expected. We have retrospectively analyzed the data of 118 premature infants born between 1982 and 1986, weighing between 750 and 1499 g. 11 of these had experienced a severe IVH/PVH and a severe RDS at the same time, whereas 75 infants did not develop either of those. (2 of the 118 showed a severe IVH/PVH without evidence of severe RDS whereas 29 developed severe RDS without signs of serious IVH/PVH. 1 could not be evaluated due to missing data). This association of severe intracerebral haemorrhage and severe respiratory distress syndrome was statistically significant (p less than 0.005). The number of severe IVH/PVH has decreased during 1984-1986 in comparison to 1982/83 (4/76 vs. 9/42; p less than 0.05); the incidence of severe RDS has slightly declined. Comparing the perinatal conditions we found that the infants of the years 1984-1986 were more rarely delivered after an interval exceeding 24 h after premature rupture of the membranes (p less than 0.05), were more often delivered by caesarean section (p less than 0.005), and were nearly always primarily cared for by an experienced paediatrician (p less than 0.01). There were no significant differences between these two groups as far as dexamethasone-prophylaxis, mean birth weight, percentage of small-for-gestational-age infants and mean Apgar scores were concerned.(ABSTRACT TRUNCATED AT 250 WORDS)

Asphyxia Neonatorum↗
PubMed1987

[Correlation of pathologic laboratory values in patients with cardiovascular diseases--consequences for diagnosis in general practice].

Coincident pathological parameters were selected from 24 laboratory-diagnostic parameters of a second stage of diagnostics after x-rays screening concerning heart and vessel diseases tested by a check representative constellation in the shape of relative frequency was determined. For the parameters cholesterol, uric acid and glucose, belonging to the metabolic syndrome, it was possible to demonstrate relations to the erythrocyte sedimentation rate. The transaminases ASAT and ALAT especially showed correlations of pathological values among one another. There were found out one-sided relations for instance concerning the proportion of transaminases, thymol turbidity test as well as creatinine to the erythrocyte sedimentation rate. The connections as has been proved appeared in female cardiac patients in a more distinct way. The results, which were interpreted in the context of a further mathematic-statistical analysis, allow the conclusions for an efficient indicational application of clinical chemical research methods in chronic heart and vessel diseases in practice.

Adolescent↗
PubMed1987

Conserved exon-intron organization in two different caerulein precursor genes of Xenopus laevis. Additional detection of an exon potentially coding for a new peptide.

From a genomic library of Xenopus laevis, two genes coding for different preprocaeruleins have been isolated and sequenced. These correspond to the type I and type III precursors analyzed previously at the cDNA level [Richter, K., Egger, R. and Kreil, G. (1986) J. Biol. Chem. 261, 3676-3680]. The type III gene comprises eight exons; the type I apparently contains eight exons as well, of which six have been sequenced. The genetic information for the dekapeptide caerulein is present on small exons of 45 base pairs. The two genes are highly homologous in their 5'-flanking region, the exon/intron boundaries, and long stretches of intron sequences. A possible scheme for the evolution of this small family of genes through exon and gene duplications is presented. In the type I gene, in place of one of the caerulein exons, a potential exon with conserved splice sites was discovered. If expressed in some frog cells, this exon would code for a new peptide 60% homologous to caerulein.

Animals↗
PubMed1987

D-alanine in the frog skin peptide dermorphin is derived from L-alanine in the precursor.

A D-alanine-containing peptide termed dermorphin, with potent opiate-like activity, has been isolated from skin of the frog Phyllomedusa sauvagei. Complementary DNA (cDNA) libraries were constructed from frog skin messenger RNA and screened with a mixture of oligonucleotides that contained the codons complementary to five amino acids of dermorphin. Clones were detected with inserts coding for different dermorphin precursors. The predicted amino acid sequences of these precursors contained homologous repeats of 35 amino acids that included one copy of the heptapeptide dermorphin. In these cloned cDNAs, the alanine codon GCG occurred at the position where D-alanine is present in the end product. This suggests the existence of a novel post-translational reaction for the conversion of an L-amino acid to its D-isomer.

Alanine↗
PubMed1987

[Problem-specific grading in disease course assessment and calculation of the likelihood of transition of chronic cardiovascular diseases].

For the course rating of cardiovascular caused drop in efficiency a problem-specific grading is introduced, the characterization of which is composed of simple, non-invasive parameters. The grading is specified for 4 clinical diagnostic classes (hypertension, coronary heart diseases, pulmonary heart, "other heart and vessel diseases") and takes into consideration the frequent coincidence or connection of several diagnoses of heart and vessel diseases with each other. The choice of parameter and connection have to fulfil the demand, which is essential for the course rating of heart and vessel diseases, like practicability proportionate with the frequency of heart and vessel diseases, adequate registration of changes in severe degrees, statement about the patient and not about several parameters. Furthermore it has to make it possible to calculate provisional probabilities under variable conditions as well as to make possible a valuation of prognosis. For that purpose the construction of suitable matrixes is shown and an integral projection is represented, which is used for the interpretation of courses dependent on severe degrees. The conception of grading has the function to modify necessary parameters for inclusion in the hierarchy according to medical starting position (for instance primary mode of registration). The model which is applicable to level of population makes possible an electronic data - processing - based evaluation including algorithmic classification.

Cardiovascular Diseases↗