Combined surface display and reformatting for the three-dimensional analysis of tomographic data

Radiologic examinations increasingly are based on sequences of cross-sectional images. In current clinical applications, the three-dimensional (3D) relationships contained in these examinations must be inferred by the observer through analysis of multiple two-dimensional (2D) images. In this article, methods for the direct display of 3D gray-level data are investigated. In the chosen approach, the 3D presentation of bone and skin surface serves to orient the viewer, while planar reformation and/or transparent projections can be applied for the assessment of soft-tissue structures in regions of interest. The resulting images represent the original image data in a way that is more suitable for observation of 3D relationships than the conventional cross-sectional viewing mode. This may facilitate the diagnostic process and enhance the interpretability of the images. Routine clinical application of this technique requires special computer hardware. Research applications, however, can be performed within tolerable times (10-30 sec/view) with computers found in radiologic research environments.

Fanconi anemia: another disease of unusually high prevalence in the Afrikaans population of South Africa

We have investigated the prevalence of homozygous and heterozygous Fanconi anemia (FA) in the Afrikaans community of the southern Transvaal Province. The minimum birth incidence of FA in white, Afrikaans-speaking South Africans was estimated to be 1 in 22,000, with the calculated heterozygote prevalence being approximately 1 in 77. Alternatively, based on a point prevalence of 1 in 26,000, the carrier rate may be estimated as 1 in 83. It is postulated that this unusually high frequency of the gene for FA is attributable to founder effect.

A unique dicentric X;Y translocation with Xq and Yp breakpoints: cytogenetic and molecular studies

A 32-year-old woman presented with secondary amenorrhea and infertility. She was of normal height and her breasts were well developed, but she had streak gonads; there were no signs of virilization, and she showed no somatic stigmata of Turner syndrome. Chromosome analysis revealed a dicentric X;Y translocation with Xq and Yp breakpoints. Centromeric banding demonstrated a Y centromere and a "suppressed" X centromere. The karyotype of the patient was interpreted as 46,X,t(X;Y)(q22;p11). The Yp breakpoint was confirmed by DNA-hybridization studies with six probes detecting Y-specific sequences. These DNA-hybridization studies were consistent with the presence of the long arm, centromere, and much of the proximal short arm of the Y. The Y-DNA studies of this female also revealed the absence of the distal short arm of the Y chromosome, to which the testis-determining factor has previously been localized.

Cytogenetic and molecular studies on a recombinant human X chromosome: implications for the spreading of X chromosome inactivation

A pericentric inversion of a human X chromosome and a recombinant X chromosome [rec(X)] derived from crossing-over within the inversion was identified in a family. The rec(X) had a duplication of the segment Xq26.3----Xqter and a deletion of Xp22.3----Xpter and was interpreted to be Xqter----Xq26.3::Xp22.3----Xqter. To characterize the rec(X) chromosome, dosage blots were done on genomic DNA from carriers of this rearranged X chromosome using a number of X chromosome probes. Results showed that anonymous sequences from the distal end of the long arm to which probes 4D8, Hx120A, DX13, and St14 bind as well as the locus for glucose-6-phosphate dehydrogenase (G6PD) were duplicated on the rec(X). Mouse-human cell hybrids were constructed that retained the rec(X) in the active or inactive state. Analyses of these hybrid clones for markers from the distal short arm of the X chromosome showed that the rec(X) retained the loci for steroid sulfatase (STS) and the cell surface antigen 12E7 (MIC2); but not the pseudoautosomal sequence 113D. These molecular studies confirm that the rec(X) is a duplication-deficiency chromosome as expected. In the inactive state in cell hybrids, STS and MIC2 (which usually escape X chromosome inactivation) were expressed from the rec(X), whereas G6PD was not. Therefore, in the rec(X) X chromosome inactivation has spread through STS and MIC2 leaving these loci unaffected and has inactivated G6PD in the absence of an inactivation center in the q26.3----qter region of the human X chromosome. The mechanism of spreading of inactivation appears to operate in a sequence-specific fashion. Alternatively, STS and MIC2 may have undergone inactivation initially but could not be maintained in an inactive state.

Acute mixed-lineage leukaemia involving myeloid and T-cell phenotypes. A case report

Among the rare acute mixed-lineage leukaemias, a myeloid T-cell phenotype has recently been recognised. An additional case characterised by myeloid cytochemistry, development of Auer rods in culture and Tdt, WT1 and T11 phenotypes on cell-marker analysis is reported. The patient died from disseminated non-reactive tuberculosis after chemotherapy.

B-cell chronic lymphatic leukemia in Hodgkin's disease. A report of two patients with unusual chromosome features

The development of B-cell chronic lymphatic leukemia in two patients who had previously been treated for Hodgkin's disease is described. In both cases aneuploidy and multiple chromosome aberrations of hemopoietic cells were evident. In one patient these changes included a clonal 14q + abnormality in association with other complex rearrangements, interpreted as translocation abnormalities involving t(6;14), 5(1;15), and t(17;19). Although the chromosome abnormalities in the other patient were nonclonal, a 14q abnormality also was detected, namely t(14q+;18q-). Other chromosome abnormalities (all nonclonal) in the two patients included translocations involving chromosome 5 and deletion of 7q in one patient and trisomy of chromosome 8 in the other. Although these abnormalities have been associated with the presence or development of non-Hodgkin's lymphoma, acute nonlymphoblastic anemia, or myelodysplastic disorders, the findings in these patients suggest that the detection of clones and potential clones with these abnormalities may be only one stage in the development of secondary malignancy.

A unique 8;16 translocation in two infants with poorly differentiated monoblastic leukemia

Acute monoblastic leukemia is nonrandomly associated with abnormalities involving 11q. Two infants, one a neonate and the other 19 months of age, had the same hitherto undescribed karyotypic abnormality, t(8;16)(p11;p13), associated with acute nonlymphocytic leukemia M5a. The older child had an additional translocation, t(10;11)(q11;p15), but the chromosome arms affected were the opposite to those described in acute nonlymphocytic leukemia M5a of childhood. Therefore, it is postulated that genes involved in monocytic differentiation may be situated on 8p11 or 16p13, as well as on 11q.

Localization of the human c-mos gene by in situ hybridization in two cases of acute nonlymphocytic leukemia type M2

The t(8;21)(q22.1;q22.3) is specific for the FAB-M2 subtype of acute nonlymphocytic leukemia (ANLL). The human c-mos protooncogene is located near the site of rearrangement on chromosome #8, at a position corresponding to band 8q22. The present in situ hybridization studies were performed in order to establish if c-mos is transposed from chromosome #8 to chromosome #21, in two cases of M2-ANLL showing the typical t(8;21). A statistical analysis of the results revealed that the c-mos oncogene was definitely not translocated from chromosome #8 to #21 in one of these patients, and was inconclusive in the other patient. The findings in the former patient suggest that either c-mos is not involved in the etiology of M2-ANLL or, alternatively, if c-mos is important in the pathogenesis of this disease, it must be activated by some mechanism other than transposition of this oncogene to an aberrant position.

Acute promyelocytic transformation of chronic myeloid leukaemia with an isochromosome 17q

Transformation to an acute promyelocytic leukaemia occurred in a patient approximately 2 years after having been diagnosed as suffering from chronic myeloid leukaemia (CML). At this time, in addition to the Ph1 chromosomal aberration, an isochromosome 17q [i(17q)] was noted. The t(15:17) was absent. The implications of this are discussed.

Inverted Y chromosome polymorphism in the Gujerati Muslim Indian population of South Africa

An inverted Y chromosome has been found at a very high frequency in a Muslim Indian community living in the Johannesburg-Witwatersrand area of the Transvaal Province of South Africa: 8 of 141 (5.7%) retrospectively identified Indian males had an inv(Y)(p11.2q11.23) and all were of the Muslim faith. The inversion was found in 22 of 72 (30.5%) prospectively studied normal Muslim Indian males. All the carriers of the inversion were Gujarati-speakers whose families migrated to the Transvaal from the Gujerat Province of India during the first half of this century. The origins of the ancestors of the individuals with inv(Y) were traced to a small village, Kholvad, near the city of Surat, and some neighbouring villages. The polymorphic frequency of the inv(Y) has probably been produced through random genetic drift in a reproductively isolated community, maintained by strict endogamous marriage customs based on religious and linguistic affiliations. There was no indication that the inverted Y was associated with any reproductive disadvantages.

Chromosome 3q21 abnormalities associated with hyperactive thrombopoiesis in acute blastic transformation of chronic myeloid leukemia

Two patients with acute blastic transformation of chronic myeloid leukemia (CML) associated with strikingly elevated platelet counts showed abnormalities of chromosome 3q in addition to the standard Philadelphia (Ph1) chromosome translocation. The first patient had an inversion of chromosome 3 (q21q26) cytologically identical to an inversion 3 previously reported in de novo acute megakaryoblastic leukemia, and the second patient showed a translocation between chromosome 3q and the chromosome 9 homologue not involved in the Ph1 translocation, [t(3;9)(q21;q34)]. Previous studies had incriminated either 3q21 or 3q26 as the locus for a regulatory thrombopoietic gene, but the current study suggests that 3q21 is the relevant site.

Hibernoma. A case report and discussion of a rare tumor

A case report is presented of a large retroperitoneal hibernoma along with the clinical, radiographic, and pathologic findings. Despite the unusual size and location of this hibernoma, the case illustrates the salient features of these rare tumors of brown fat origin. Pitfalls in preoperative diagnosis are discussed. To date, there has been no convincing evidence of malignant potential of this tumor, and total excision remains the treatment of choice.

Hibernoma. A case report and discussion of a rare tumor

A case report is presented of a large retroperitoneal hibernoma along with the clinical, radiographic, and pathologic findings. Despite the unusual size and location of this hibernoma, the case illustrates the salient features of these rare tumors of brown fat origin. Pitfalls in preoperative diagnosis are discussed. To date, there has been no convincing evidence of malignant potential of this tumor, and total excision remains the treatment of choice.

Interscalene brachial plexus block anesthesia for upper extremity surgery

Use of the interscalene brachial plexus block for upper extremity anesthesia in a primarily rheumatoid population is reviewed in 88 cases. The interscalene approach described by Winnie was used. Anesthesia was effective in 93% of the cases. Failure to achieve anesthesia was more likely to occur in surgical procedures on the distal upper extremities. The technique allowed effective and reliable anesthesia throughout the upper extremity, including the shoulder. Problems associated with other forms of upper extremity regional anesthesia, such as tourniquet pain, pneumothorax, systemic anesthetic toxicity, and inadequate duration of anesthesia, were not encountered. Difficulties with more distally based block administration due to decreased shoulder motion were obviated.

Shading 3D-Images from CT Using Gray-Level Gradients

For the 3D-reconstruction of organ surfaces from tomograms, a shading method based on the partial volume effect is presented. In contrast to methods based on the depth and/or the angle of the voxel surface, here the gray-level gradient along the surface is used for shading. It is shown, that at least for bone and soft tissue surfaces, the results are superior to conventional shading. This is due to the high dynamic range of the gray levels within a small spatial neighborhood.

Acute childhood leukemia in Johannesburg. Ethnic differences in incidence, cell type, and survival

Acute childhood leukemia was found to be less common in black children than in white children in the Johannesburg area of South Africa. Of 195 consecutive patients, 78 were black and 117 white. The annual incidence was 0.8/100,000 black children and 3.3/100,000 white. The low incidence in black children was due to the very low incidence of acute lymphoblastic leukemia (ALL), which was 0.41/100,000 black children compared with 2.73/100,000 white children. The incidence of acute nonlymphoblastic leukemia (ANLL) was approximately the same for both ethnic groups; 0.38/100,000 black children and 0.57/100,000 white children. Remission rates for black children with ALL were lower than for white children and the cumulative proportion of black patients surviving at 60 months was only 32% compared with 72% of white patients (p = 0.0001). The most significant poor prognostic factors in ALL were ethnic group and age (p = 0.0006), CNS disease at onset (p = 0.006), FAB L2 and L3 morphology (p = 0.05), and irregular clinic attendance during maintenance therapy (p = 0.05). In ANLL, remission and survival rates were less favorable than in ALL but there were no significant differences between black and white patients. Black patients exhibited certain clinical features rarely seen in white patients, including chloromata, oropharyngeal lesions, and CNS involvement at onset. Karyotypic abnormalities were common. The most significant poor prognostic factors in ANLL were CNS disease at onset (p = 0.03), generalized lymphadenopathy (p = 0.0001), and FAB morphology classification M3-M6 (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute megakaryoblastic leukaemia with 3q inversion and elevated thrombopoietin (TSF): an autocrine role for TSF?

A patient with acute megakaryoblastic leukaemia is described in whom exactly the same paracentric inversion of 3q was detected as in three previously documented cases. The patient's serum thrombopoietin (TSF) was significantly raised. Based on these findings we postulate a role for a gene (? oncogene) on chromosome 3q in thrombopoietin production. Abnormalities of 3q may assist in delineating a subgroup of acute nonlymphocytic leukaemia, namely acute megakaryoblastic leukaemia.

Segregation patterns and phenotypes of unbalanced offspring in a large family with (10;18) chromosome translocation

We describe a large family in whom a balanced 10;18 chromosome translocation is segregating through five generations. Six severely mentally retarded relatives and an abnormal fetus further define the phenotypic expression of dup (18q21----qter). Other segregants detected prenatally included a fetus with deletion 18q21----qter and two fetuses with dup(18pter----q21) owing to tertiary trisomy. One of the latter also had an extra X chromosome; this might be another example of possible nonhomologous pairing in man.

Chorionic villus sampling for first trimester diagnosis of beta-thalassaemia. Report of the first South African case

The first South African report of chorionic villus sampling for molecular diagnosis of beta-thalassaemia in a 10-weeks' pregnant Indian Muslim woman is presented. The sampling procedure and molecular techniques for sexing the fetus and establishing whether it was affected by beta-thalassaemia are described. From the sample of villi obtained a male fetus was identified, using an X-Y-specific DNA probe. A preliminary family study on both parents, the affected proband and his 4 phenotypically normal siblings, revealed two informative restriction fragment length polymorphisms in the mother, but none in the father. It was therefore not possible to differentiate between the two beta-globin gene alleles of the father. The fetus thus had a 50% chance of being a heterozygote or a 50% risk of being affected. Synthetic oligonucleotide hybridization of parental and fetal DNA was attempted by the Genetics Unit of Johns Hopkins Hospital, Baltimore, but the fetal hybridization was unsuccessful. Results on the parents were obtained too late to be of assistance in the present pregnancy as the parents requested termination of the pregnancy before 16 weeks' gestation for religious reasons.

The PLC/PRF/5 human hepatoma cell line. I. Reevaluation of the karyotype

The karyotype of the PLC/PRF/5 (Alexander) human hepatoma cell line was identified at passage +/- 110, prior to attempting in situ hybridization studies to determine the chromosomal localization of the hepatitis B virus (HBV) DNA integration sites. The karyotype was established by means of G-, Q-, and sequential C-banding techniques. Multiple consistent numerical and structural abnormalities were detected. These were compared with the original published unbanded karyotype of this cell line (at passage less than 25) and also with a previously published banded karyotype (at passages 60-90). Despite minor differences in the compared banded karyotypes (which are probably interpretational), the concordance in modal number and morphological karyotypic similarities over the course of 10 years indicate that this cell line is stable in vitro.

The PLC/PRF/5 human hepatoma cell line. II. Chromosomal assignment of hepatitis B virus integration sites

The chromosomal sites at which hepatitis B virus (HBV) DNA is integrated into the genome of the hepatocellular carcinoma (HCC) cell line, PLC/PRF/5 were investigated in an attempt to understand the mechanisms by which hepatitis B virus may induce malignant transformation. In situ hybridization of an HBV DNA probe to metaphase chromosomes of the PLC/PRF/5 cell line, followed by statistical analysis, identified three integration sites; these were 15q22-q23, 11q22, and 18q12. In particular, hybridization to chromosome #15, which is present in four copies in complete metaphases of this cell line, was highly significant (p much less than 0.0005).