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Biomedical subjects

B Erdtmann

Publications and source records attributed to B Erdtmann.

36 records · Page 2Linked to original sources
PubMed1994

Intravascular ultrasound: value of electronic and mechanical devices for quantifying mild to moderate atherosclerosis.

To define the accuracy of electronic and mechanical ultrasound (US) devices for determining the thickness of intima and media, 32 fresh normal and atherosclerotic human femoral arteries were obtained at necropsy. The samples were imaged with a 64-element array and a mechanically rotating US transducer at 20 MHz. The mean thickness of the intimal and medial layer was measured with electronic calipers followed by histopathologic and micromorphometric analysis. Morphometric correlation for intima showed r = 0.64 for the electronic and r = 0.58 for the mechanical US device. The correlation between ultrasonic and histologic measurement of medial thickness in normal and diseased specimens was r = 0.79 for the multielement and r = 0.76 for the mechanical transducer. In conclusion, multielement array transducers are equivalent to mechanically driven probes in the quantitative assessment of peripheral arterial wall layers. Both systems lack sufficient accuracy in the determination of mild to moderate intimal thickening.

Arteriosclerosis↗
PubMed1992

Analysis of clastogenic effect of Porto Alegre drinking water supplies on mouse bone marrow cells.

Studies were conducted to evaluate the clastogenic activity of drinking water from Porto Alegre and Guaíba (Rio Grande do Sul, Brazil) estuarine waters. Mouse bone marrow was the target organ. C57B1/6 male and female mice received the water samples as their only liquid supply. Bone marrow cells were collected on the 16th day after the beginning of treatment. The analysis of metaphases demonstrated that the water supplies did not increase the structural chromosome aberration frequencies compared to the control groups. Concerning numerical alterations, only one treated female group showed a significant difference (loss of one chromosome) when compared to the control group, but this result is not considered relevant.

Animals↗
PubMed1990

The effect of the pyrrolizidine alkaloid integerrimine on the chromosomes of mouse bone marrow cells.

In an investigation of the action of integerrimine on chromosomes, the bone marrow was taken as target organ. Male and female mice of the C57Bl/6 strain received a single acute dose of this pyrrolizidine alkaloid, in 2 concentrations: 18.75 and 37.50 mg/kg. Bone marrow cells were collected 6, 12 and 24 h after treatment. The analysis of metaphasic chromosomes demonstrated that chromosomal damage occurs, correlated with drug concentration. The greatest frequency of chromosomal aberrations was detected 12 h after treatment.

Animals↗
PubMed1989

Densitometric measurements of C bands of chromosomes 1, 9, 16, and Y in leukemic and preleukemic disorders.

Fifty-six patients with blood disorders (23 with chronic myeloid leukemia, 14 with acute myeloblastic leukemia, seven with acute lymphoblastic leukemia, one with chronic lymphocytic leukemia, and 11 with preleukemia states) were studied. A quantitative and objective method of C band length analysis with well-matched controls was used. The C bands of chromosome pairs 1, 9, and 16 presented a normal distribution that was similar in patients and controls, whereas the Y chromosome presented an abnormal distribution. Smaller C bands in 1qh and higher indexes of intrapair heteromorphism in pairs 1 and 9 were detected in the CML group; the group of acute leukemias (myeloblastic and lymphoblastic) presented a smaller index only in pair 1qh. No other differences in length, heteromorphism, inversion frequency, or sex were detected.

Adult↗
PubMed1985

Equivalence of the total constitutive heterochromatin content by an interchromosomal compensation in the C band sizes of chromosomes 1, 9, 16, and Y in Caucasian and Japanese individuals.

A quantitative analysis of C bands by densitometric measurements in chromosomes 1, 9, 16, and Y was conducted in Caucasians and Japanese living in Brazil. Sixty normal unrelated subjects (30 males and 30 females) were studied in each racial group. Caucasians presented C bands of chromosomes 1, 9, and 16 larger than Japanese, but, on average, only the difference for C bands of chromosome 9 was statistically significant. In the Japanese, the C band sizes of chromosomes Y were, on average, significantly larger than in the Caucasians. The mean C band size of chromosome 9 and the sum of the three pairs were significantly larger in Caucasian than in Japanese males. The total values of constitutive heterochromatin, sigma (1qh,9qh,16qh,Yq12), did not show significant difference between Caucasian and Japanese males. The relative C band sizes of chromosomes 1, 9, and 16 were, on average, similar in Caucasians and Japanese. No sex difference was found in both racial groups. As regards the heteromorphism, only the values of C bands of chromosome 9 were, on average, significantly larger in Caucasians than in Japanese. Partial inversions were detected only among the Caucasians.

Adult↗
PubMed1984

Quantitative analysis of C bands in chromosomes 1, 9, 16 and Y in Caucasian and Japanese males.

A comparative analysis of the C bands of chromosomes 1, 9, 16 and Y of 27 Caucasian and 27 Japanese males is reported. The mean of the total centromeric heterochromatin of the three pairs (sigma h1, 9, 16) is larger in Caucasian than in Japanese subjects, but Caucasians showed a lower mean of C band size of chromosome Y. Heritability of the C band of the Y chromosome was studied in 26 families.

Asian People↗
PubMed1982

Aspects of evaluation, significance, and evolution of human C-band heteromorphism.

The C-band heteromorphism may be evaluated in different forms. The results obtained from classification are easily influenced by subjective factors, and the conclusions of such types of data are acceptable only if they are well matched with a control. The length measurement is simple to obtain, and a quantitative presentation of the data, with correction for the contraction stage of the chromosomes, is considered the most efficient method to evaluate the C-band size heteromorphism. Excluding the acrocentrics, whose short arms present a complex heteromorphism, and the chromosome Y, whose variable C band is terminal, all others present C-band location heteromorphism except pair 16. It is possible to multiply the detectable heteromorphisms in some bands by using diverse staining methods. The present state of knowledge about the role of heterochromatin in the cell is analyzed, as is the effect of C-band variability on the phenotype, the reproductive fitness, and the individual viability. Although a great amount of data is available, no result can be considered definitive as yet. Aspects in which the use of C-band heteromorphisms are profitable are considered.

Adult↗
PubMed1982

Quantitative analysis of C-band size in human chromosomes.

The C-bands of chromosomes 1, 9, 16 and Y of 434 individuals were measured using densitometry. The regression coefficients observed between the length of these regions and that of lq-h varied between 0.046 and 0.189, showing a clear size effect (the larger the band, the higher the contraction per unit size). Negative regressions between the band sizes of the autosomes and the time that elapsed between fixation and band induction were also observed as well as an effect of the treatment (in average, the CBG-bands were 17% larger than the CNG ones). Appropriate methods were developed to correct for these factors. Despite that, correlations between the heterochromatic regions of chromosomes 1, 9 and 16 remained significantly positive (0.15-0.24). The y distal heterochromatin showed the same rate of contraction as the others. But it was not influenced by the slide's age or the different methods of band induction. It showed no relationship, after correction, with the C-bands of chromosomes 1 and 9, but the correlation with those of chromosomes 16 remained positive (0.25 and 0.26).

Brazil↗
PubMed1981

Quantitative analysis of C bands in chromosomes 1, 9, and 16 of Brazilian Indians and Caucasoids.

Densitometric C-band measurements in chromosomes 1, 9, and 16 of 394 Indians and 40 Caucasoids living in Brazil are reported. No significant intratribal variability in the average length of these regions was observed, and the intertribal variation showed no consistent patterns. But the Caucasoids always presented lower means. The relative C-band sizes of these three chromosomes, however, were very similar in Indians and Caucasoids. The indices of heteromorphism displayed analogous results; only in chromosome 16 are they dissimilar in these two ethnic groups. An unexpected sex difference was observed in the C-band sizes of this chromosome, females uniformly presenting higher averages than males. Centromeric heterochromatin appeared in 6% and 9% respectively of the short arms of chromosomes 1 and 9 among the Caucasoids, while among the Indians its prevalence was 2% in both chromosomes.

Brazil↗
PubMed1981

Familial pericentric inversion of chromosome 2.

A pericentric inversion of chromosome 2 was detected in eight members of a family ascertained via a proband with congenital jejunal atresia born of consanguineous parents. The latter affection was also present in one of his sibs. Microdensitometric analysis of the patterns of G bands of the inverted segment revealed a balanced rearrangement with unusual break points in p12 and q36; the association with the disease is apparently coincidental.

Abnormalities, Multiple↗
PubMed1979

Epidemiologic studies among Amerindian populations of Amazonia. II. Prepvalence of Mansonella ozzardi.

The prevalence of microfilaremia among Indians in 13 Amazon Indian villages was determined by examining Giemsa-stained peripheral blood smears and preparations from peripheral blood lymphocyte cultures. Mansonella ozzardi was the only species found in the 601 persons tested. Prevalence was highly village-specific, ranging from 0% in four villages to as high as 93% among persons aged 10 years and older in others. Comparisons of the two methods showed that the concentration effect of the peripheral blood lymphocyte culture preparations allowed the detection of a greater number of microfilaria-positive persons, especially women and children with lower levels of parasitemia.

Adolescent↗
PubMed1975

Chromosome studies in patients with congenital malformations and mental retardation.

16 (41%) out of 39 individuals referred by physicians because of sexual anomalies showed abnormal karyotypes; the corresponding figure for those investigated due to suspected autosomal aberrations was 37 out of 104 (36%). A special survey was also conducted among 51 mentally defective children with at least 3 malformations; 5 individuals (10%) were observed with chromosome abnormalities plus 3(6%) with rare variants. These results were compared with those presented in 26 other surveys reported in the literature.

Abnormalities, Multiple↗
PubMedDate not supplied

Size variability of the Y chromosome distal C-band in Brazilian Indians and Caucasoids.

Densitometric measurements of the Y chromosome distal heterochromatin were performed on 183 Indians and 21 Caucasoids living in Brazil. No significant intratribal intervillage variation was observed, but the tribal averages were different, ranging from 0.81 to 1.32 mu. The Caucasoid mean presented an intermediate value. Wide intrapopulation variability occurs, as well as a suggestion of bimodality in the measurements obtained among the Indians of the Amazon region. Surprisingly a positive correlation was found between this variable and the C-band size of chromosome 16, as well as between it and the heteromorphism index of chromosome 1.

Adult↗
PubMedDate not supplied

A cytogenetic survey of five breeds of cattle from Brazil.

One-hundred-and-thirty-nine animals from five breeds of cattle were studied cytogenetically. Three types of karyotype abnormalities were detected, two of them structural, t(1; 29) and ins(16), and one numerical (60,XY/61,XY + F). The first two, found in the Charolais race, presented familial recurrences; the last one, observed in the Norman breed, was sporadic. Pedigree studies showed that ins(16), an aberration not previously described in cattle, segregated in the ratio of 5 carriers to 10 normals. t(1; 29) occurred in mother and daughter. A variant of constitutive heterochromatin also presented familial recurrence in the Charolais breed.

Animals↗