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A Rodewald

Publications and source records attributed to A Rodewald.

At least 19 recordsLinked to original sources

[Reliability of quantifying vascular white matter brain lesions -- a contribution to reproducible quantitative diagnosis].

PURPOSE: Microangiopathic lesions of the brain tissue correlate with the clinical diagnosis of vascular subcortical dementia. The "experience-based" evaluation is insufficient. Rating scales may contribute to reproducible quantification. MATERIALS AND METHODS: In MRI studies of 10 patients, 9 neuroradiologists quantified vascular white matter lesions (WMLs) at two different points in time for 12 anatomically defined regions with respect to number, size and localization (score). For 9 observers and 10 studies, 90 intra-observer differences were obtained for each of the 12 WML scores. To calculate the inter-observer reliability, rating pairs were formed. Furthermore, 360 differences were computed for each score and rating for 12 anatomically defined WML scores, and the intraclass correlation (ICC) was calculated as a measure of agreement (reliability). RESULTS: As to the intra-observer reliability, the median of the differences was 1.5 for the entire brain as opposed to 0 for defined brain regions. The corresponding values for the inter-observer reliability were 3 and 1, respectively. The mean intra-class correlation coefficient for the 10 studies was 0.88, whereas the mean interclass correlation concerning the inter-observer reliability was 0.70, with the first and second rating being averaged. The rating of each study took about 6 minutes. CONCLUSION: The rating scale with high intra- and inter-observer reliability can dependably quantify WMLs and correlates with the clinical diagnosis of vascular dementia. Using a reliable rating scale, the diagnostic distinction of age-associated physiological vs. pathological size of the WML can make a contribution to the reproducible quantifiable diagnostic evaluation of vascular brain tissue lesions within the framework of dementia diagnostics.

Aged↗

Maternal uniparental disomy (UPD) for chromosome 2 discovered by exclusion of paternity.

Serological and molecular (DNA-STR) analysis of a paternity case demonstrated exclusion of paternity of the presumptive father in two markers (ACP and Apo B, both localized on chromosome 2, region 2p25.2 and 2p23/24, respectively) in a phenotypically normal girl with a normal karyotype 46,XX (by GT-banding). The index of paternity calculated for other serological (seven erythrocyte antigens, six serum protein systems, and seven isozymes, as well as the A- and B-HLA loci) and nine DNA markers, excluding ACP and Apo B, gives a very high (virtually certain) degree of paternity for the presumptive father. Maternal uniparental disomy (UPD) for chromosome 2 was suspected. Evaluation of polymorphic DNA markers (STRs) spanning chromosome 2 of the child, mother, and presumptive father demonstrated that the girl had inherited two maternal chromosome 2 homologues, whereas alleles for markers from other chromosomes were inherited from the father in a Mendelian fashion. The girl was homoallelic for informative markers mapping to the chromosomal regions 2p23-25, but she was heteroallelic for informative markers on the long arm of chromosome 2, establishing that the maternal UPD with partial isodisomy of the short arm was caused by a meiosis I nondisjunction event with genetic recombination (chiasmata in this region 2p23-25) during oogenesis.

Blood Group Antigens↗

Genetic structure of a Sakha population from Siberia and ethnic affinities.

The red cell enzymes ACP1, ESD, GLO1, PGM1 and RDS and the serum proteins GC, HP, PI, and TF were determined for samples of 150 and 144 Sakha, respectively. The Sakha, a Turkic-speaking population, inhabit the Sakha-Yakutia Republic in northeastern Siberia. High gene frequencies were found for ACP1*A, GLO1*1 and GC*1F, whereas no P1*S or P1*Z alleles were found. In addition, 1 heterozygous phenotype with ACP1*C and 2 heterozygous phenotypes with ESD*7 were found. The genetic distance measures show close affinities of the Sakha population to Buryats (especially Western Buryats), Mongols, and Evenks, whereas the genetic distance to Turkic-speaking Altay and Tuvan populations is great.

Blood Proteins↗

Genetic study of African populations: polymorphisms of the plasma proteins TF, PL, F13B, and AHSG in populations of Namibia and Mozambique.

Genetic variations of four highly polymorphic serum proteins, TF, PI, F13B, and AHSG, were tested to distinguish one black African and one Khoisan population of southwest Africa. The results show that indeed the systems TF, PI, and AHSG are of high value for anthropological genetics: The allele frequencies for these systems enable clear identification of and distinction between black African and Khoisan populations. The F13B locus, on the other hand, reveals for both the black African and the Khoisan populations specific and unique African variants: a high frequency of F13B*2 and the lowest frequency of F13B*3 so far worldwide. The new data are compared with results for TF and PI in another black African population of Mozambique, which Rodewald et al. (1988) had studied previously. The dendrogram, based on genetic distance data D and average linkage cluster analysis, shows minimal distance between both black African populations of Namibia and Mozambique and marked distance between those and the Khoisan population of Namibia.

Alleles↗

Serological analysis of the Abbad Tribe of Jordan.

The Abbad are one of the largest tribes in Jordan with a complex structure dictated by historical and cultural factors. To study the genetic variability within the tribe, we examined four samples representing different levels of tribal structure for the polymorphisms of five blood groups, five erythrocyte enzymes, and seven serum proteins. The obtained allele distributions indicate a wide range of genetic variability within the tribe. An allelic heterogeneity test revealed significant differences between the examined samples, yet a gene diversity analysis revealed no significant substructuring. The observed genetic relationships among the four samples appear to agree with the tribal organization. Endogamous mating within the tribe and inbreeding within the subunits are believed to be the main factors that influenced the observed variability. This was confirmed by the results of the R matrix analysis, which summarized the genetic relationships in concordance with intertribal admixture, when affiliation and historical and maternal links were considered. The study is also an example of gene diffusion and of a negative relationship between the FY A-B- phenotype and endemicity of malaria.

Adolescent↗

The distribution of plasminogen (PLG) polymorphism in the Namibian !Kung San and Kavango populations.

Genetic polymorphism of the PLG serum protein was examined in the Namibian !Kung San and Kavango (Bantu) populations by means of IEF technique. The two samples revealed very similar allele frequencies (!Kung San: PLG*A = 0.8351, PLG*B = 0.1649; Kavango: PLG*A = 0.8228, PLG*B = 0.1732 and PLG*M4 = 0.004). The Namibian distributions were within previously observed African PLG ranges. The effects of natural selection were also discussed.

Adult↗

Microevolution and genetic affinities among six Amerindian tribes of lower Central America: comparative genetic study of serum proteins.

We evaluate the pattern of genetic variation among native Mesoamerican Amerindians by the construction of a gene frequency map that reflects the past action of evolutionary forces. The analysis is based on the theory that genes of modern human populations carry the encoded history even of humans' remote past and their early wanderings around the globe. We examined the serum proteins TF, PI, F13B and AHSG on 491 samples of 6 Mesoamerican Amerindian tribes (Guaymi, Bribri, Cabecar, Teribe, Guatuso, and Huetar) and 2 tribal mixed samples (Teribe x Guaymi and Bribri x Cabecar). We find a distinct genetic pattern in the examined tribes that clearly separates the Mesoamerican Amerindians from other living Amerindian groups. The proteins, TF, PI, and AHSG proved to be especially rich in special genetically fixed variants and polymorphisms, and F13B proved to be a powerful genetic marker to distinguish human groups. Using Nei's distance D and Mahalanobis's D2, we compared the polymorphisms and allele frequencies at the four serum protein loci to discern degrees of similarity between the samples. These data are presented in the dendrograms computed by average linkage cluster analyses and in two kinds of unrooted phylogenetic trees, neighbor-joining trees and split decompositions. Estimations are made on Hardy-Weinberg equilibrium and on genetic diversity and average heterozygosity index.

Blood Proteins↗

HP and GC subtype distribution in the !Kung San and Kavango in Namibia.

The distribution of the HP and GC serum protein polymorphisms in the !Kung San and Kavango (Bantu) populations in Namibia were examined. The obtained allele frequencies of GC marker system were very similar in both populations (GC*1F approximately equal to 0.80, GC*2 approximately equal to 0.10), while the distributions of the HP subtypes in the !Kung San sample (HP*1F = 0.0967, HP*1S = -.1452, HP*2FS = 0.7581) differed markedly from those in the Kavango one (HP*1F = 0.3791, HP*1S = 0.2375, HP*2S = 0.375). These results confirm previously reported allelic distributions in ethnically similar populations.

Adult↗

Dermatoglyphic peculiarities in patients with Williams-Beuren syndrome.

The dermatoglyphic patterns of fingertips and palms of 115 patients with Williams-Beuren syndrome (WBS) were analysed and compared with the data from 199 control individuals from Germany. The following combination of dermatoglyphic patterns appears to be characteristic to WBS: an excess of whorls on all fingertips; high termination values of the main lines D, B, and A; frequent absence of C triradius (C0); high frequencies of ulnar loops on the hypothenar and distal loops on the 2nd, 3rd, and 4th interdigital areas, of distal axial triradii t", and of abnormal palmar creases such as simian crease and Sydney lines. The combination of fingertip and palmar patterns expressed by a "Log.Score-Index," provides a high degree of discrimination between the WBS patients (92%) and the control group (88%). A "phantom picture" for WBS was constructed, which can be used for its diagnosis.

Abnormalities, Multiple↗

Cytogenetic survey of 32 cancers of the prostate.

Cytogenetic studies after short-term culture were performed on 32 adenocarcinomas of the prostate from patients without prior treatment. The tumor specimens, ranging from stage B1 to D1, were obtained by radical prostatectomy or diagnostic biopsies. Fourteen tumors showed a normal diploid chromosome complement in all metaphases examined. Clonal chromosomal alterations were detected in 16 tumor samples and the remaining two cases contained double minute (dmin) chromosomes in some cells. The most frequent numerical changes included loss the Y chromosome and trisomy 7, both found in four cases. The only recurrent structural aberration was del(10)(q24), seen in three cases both as a sole anomaly and within multiple rearrangements. Six patients showed cytogenetically unrelated clones. The occurrence of the chromosomal changes found in this study shows no relationship to certain histopathologic characteristics of the tumors. The recurrent finding of del(10)(q24) as sole anomaly and the evidence for clonal evolution in one patient demonstrates that this change is an early karyotypic event which may be important for the pathogenesis in at least a subset of prostatic cancers.

Chromosome Aberrations↗

Dermatoglyphics in type 1 diabetes mellitus.

Although fingerprints and handprints are widely used in criminology, it is only recently that this approach has been applied to the field of medical and genetic diagnoses. In order to investigate dermatoglyphics in Type 1 diabetes mellitus, quantitative characteristics of fingers and palms (ridge count and main line indices) as well as qualitative parameters such as digital and interdigital patterns, the position of the palmar axial triradii and main line courses were analysed in 88 male and 108 female Type 1 diabetic patients and compared with data from 100 male and 99 female normal controls. Type 1 diabetic patients show a lower third finger ridge count (p < 0.05) and a-b ridge count (p < 0.001) and higher transversality of the main lines as indicated by the main line index value (p < 0.001) or the ending of the main line A in a specific sector 5, 5', and 5" (p < 0.001) compared with controls. In addition, diabetic patients show higher frequency of palmar axial t' and t" triradii (p < 0.001) and a lower frequency of 'true' patterns in the fourth interdigital and thenar area (p < 0.001) than controls. By multivariate analysis of quantitative and qualitative variables a predictive value of 78.6% and 77.3%, respectively, for male, and 81.4% and 82.2%, respectively, for female Type 1 diabetic patients was found. In conclusion, dermatoglyphics seem to be an interesting tool for genetic studies related to Type 1 diabetes.

Dermatoglyphics↗

[Quantitative dermatoglyphic markers in fra-X-syndrome].

Quantitative dermatoglyphic characters of fingers and palms of 61 male patients with fra-X-syndrome and 20 female heterozygote carriers were analysed and compared with the data from 84 male and 90 female normal individuals. Univariate and multivariate analysis of the data led to the following conclusions: 1. The fra-X-syndrome patients show higher ridge count and higher MLI value (increased transversality of the main lines), and lower a-b ridge counts than the controls. In addition to this, differences are observed also for the diversity and asymmetry measures. 2. Discriminant analysis as applied to the sexes separately, showed that 75% of males can be correctly classified in their group. However, the percent of correctly classified females is lower than the males; it is 70% (fra-X female) ad 64.4% (control female). 3. D2-matrix and the comparison of TFR C values support the hypothesis of X-chromosomal doses effect on the dermatoglyphics.

Adult↗

Genetic transferrin types and iron-binding: a comparative study of a European and an African population sample.

Two population samples, one from Europe and one from Africa, were analyzed for the distribution of genetic transferrin (TF) types, serum concentrations of TF, serum iron concentrations and free iron-binding capacities. In Europeans the distribution of the TF alleles was C1 = 0.816, C2 = 0.143, C3 = 0.037, and B2 = 0.004. In black Africans the allele frequencies were: C1, 0.823; C2, 0.104; and D1 = 0.073; TFC3 was absent. The mean serum concentrations were 362 +/- 88 mg/dl in Europeans and 528 +/- 176 mg/dl in Africans; this difference was statistically significant. The concentration of serum immunoglobulins was also elevated in black Africans although their health was reported to be normal. The serum iron concentrations in Africans were decreased; the free iron-binding capacity of TF was, thus, increased. In both population samples there was a tendency for slightly higher TF concentrations in the TF C1 subtype than the TF C2 subtype. This correlation was not statistically significant. Analysis of a larger sample is required to establish this relationship.

Alleles↗

Dermatoglyphic peculiarities in families with X-linked mental retardation and fragile site Xq27: a collaborative study.

The dermatoglyphic patterns of fingertips, palms and soles of 75 male patients with X-linked mental retardation and fra-Xq27 and of 28 obligate female heterozygotes were analyzed and compared with the data from 200 male and 200 female control individuals. The results show that there is a strong association between the fra-X-syndrome and dermatoglyphic peculiarities observed in male patients and also in female heterozygotes. The characteristic dermatoglyphic features of the fra-X-syndrome are: increased frequencies of radial loops, whorls and arches on the fingertips, a pronounced transversal course of palmar ridges, lower a-b RC, absence of c-triradii on the palms, abnormal palmar and plantar creases, dysplasia of the papillary ridges and low frequencies of true patterns on the soles. Some of these patterns were found in the female carriers of fra-Xq27 also. The combination of palmar and plantar patterns, expressed by a "log. score-Index", provides a high degree of discrimination between the male patients with fra-X-syndrome and the control group. A preliminary log. score-Index was developed also for the female heterozygotes. A "phantom picture" of the dermatoglyphic stigmata is constructed. We suggest that dermatoglyphic examination of the members of families suspected for fra-Xq27-syndrome can be useful for predicting this state and for diagnosing male hemizygotes and carrier females.

Adolescent↗

Interstitial de novo deletion of the long arm of chromosome 5: mapping of 5q bands associated with particular malformations.

A new case of interstitial deletion of the long arm of one chromosome No. 5 (q13 leads to q22) is described. The girl shows mental retardation, severe hypotonia, dysmorphic facies and peculiar dermatoglyphics. The relationship between partial trisomies and partial monosomies of 5q chromosomal segments and associated clinical features is discussed. It seems possible to draw a rough phenotypic map of the long arm of chromosome 5 (5q), correlating observed malformations and phenotypic features with specific chromosomal regions.

Abnormalities, Multiple↗