Quantifying chromosome changes and lineage involvement in myelodysplastic syndrome (MDS) using fluorescent in situ hybridization (FISH)

A simplified technique for fluorescent in situ hybridization (FISH) was used to investigate the prevalence of chromosomally abnormal clones in 13 cases of myelodysplastic syndrome (MDS). Biotinylated centromeric probes for chromosomes 7, 8, 12 and X, as well as painting probes for chromosomes 7 and 11, were applied to air-dried bone marrow smears stored from 6 to 23 months. Nine of the cases had been previously karyotyped, and five of these demonstrated normal karyotypes which were confirmed by FISH. The remaining four cases showed different chromosome changes. One case of sideroblastic anemia with chronic lymphocytic leukemia showed minor clones with either monosomy 12 (12% of cells) or tetraploidy (15% of cells) by FISH, whereas metaphase cytogenetics had demonstrated trisomy 12 in 20% of cells, with no evidence of tetraploidy. Another case which had been previously karyotyped was found to have a t(7;11) in 90% of cells while only 10% of cells were shown by FISH to contain this translocation. Monosomy 7 was demonstrated by FISH in a case of refractory anemia (RA), while trisomy 8 was found in a case of RA with excess blasts in transformation (RAEB-T), and in both of these cases the aneuploid clone was present in eosinophils as well as in erythroid and granulocytic precursors but not in lymphocytes or histiocytes, thereby demonstrating the value of FISH for identifying the affected cell lineage.

Laminin adhesion-selected primary human colon-cancer cells are more tumorigenic than the parenteral and nonadherent cells

Laminin has been shown to promote the malignant phenotype and the level of the 32/67 Kd laminin receptor has been found to correlate with Dukes' staging of colon cancer. A biopsy of a Dukes' stage B2 human colon carcinoma formed a tumor in a nude mouse after coinjection with Matrigel. The parental tumor and the murine tumor appeared identical at the histological level. A cell line LCC-C1 was established from the murine tumor. The cell line appeared moderately differentiated although it did not produce mucin in vitro; however, the xenograft in vivo did produce low levels of mucin. Laminin adherent and non-adherent cell lines were selected. The parental and the laminin-selected cell subclones adhered equally well to plastic and to fibronectin and showed similar growth rates on plastic. When injected subcutaneously into nude mice, the laminin-adherent cells formed relatively undifferentiated tumors that were twice as large as the parental cell tumors whereas the laminin non adherent cells formed very small, but highly differentiated tumors. These data demonstrate that subpopulations of tumor cells which differ in their tumorigenic properties can be selected based on their adhesion to laminin and thus provide models for studying the mechanisms of tumor growth.

Intestinal and pelvic endometriosis presenting as a tumor and associated with tamoxifen therapy: report of a case

BACKGROUND

Tamoxifen has been used in the adjuvant treatment of breast cancer because of its antiestrogenic effects. However, recent reports have shown it to have estrogenic effects as well. The purpose of this report is to describe a potential association between tamoxifen therapy and endometriosis.

CASE

A 50-year-old postmenopausal woman who had received 2 years of adjuvant tamoxifen therapy for breast carcinoma developed extensive tumor-like endometriosis necessitating extensive pelvic and intestinal surgery.

CONCLUSION

This case report highlights the need for obstetricians and gynecologists to be familiar with the actions of tamoxifen and its potential complications.

Injectable alginate seeded with chondrocytes as a potential treatment for vesicoureteral reflux

Injection of polytetrafluoroethylene (Teflon) or collagen has been used in the endoscopic treatment of vesicoureteral reflux. Although the principle of an endoscopic treatment is valid, there are concerns regarding the long-term safety and effectiveness of these substances. The goal of several investigators has been to find alternate implant materials that would be safe for human use. Toward this goal we conducted a study to determine the effect of chondrocytes using a biodegradable polymer solution as a template. Hyaline cartilage was obtained from the articular surfaces of calf shoulders and chondrocytes were harvested. Chondrocyte suspensions were concentrated to 20, 30 and 40 x 10(6) cells per cc and mixed with dry alginate powder (a biodegradable polymer) to form a gel. Twelve athymic mice were injected subcutaneously with a chondrocyte-alginate solution. Each mouse had 4 injection sites, consisting of control, 10, 15 and 20 x 10(6) chondrocyte cells (48 injection sites). Mice were sacrificed at 2, 4, 6 and 12 weeks after injection. Histological examination of the injection sites demonstrated evidence of cartilage formation in 34 of the 36 experimental injection sites. Gross examination of the injection sites with increasing time showed that the polymer gels were progressively replaced by cartilage. The ultimate size of the cartilage formed was related to the initial chondrocyte concentration injected, and appeared to be uniform and stable within each category. There was no evidence of cartilage formation in the 12 controls. Histological analyses of distant organs showed no evidence of cartilage or alginate gel migration, or granuloma formation. In conclusion, chondrocyte-alginate gel suspensions are injectable, appear to be nonmigratory and are able to conserve their volume. In addition, the use of autologous cartilage cells would preclude an immunological reaction. These preliminary studies indicate that autologous cartilage-polymer gel solutions may be potentially useful in the endoscopic treatment of reflux.

Antidromic sensory nerve conduction studies of medial and lateral plantar nerves in normals

A reliable sensory nerve conduction study for the most distal lower extremities is needed in routine clinical electromyography. This paper reports a study of 150 medial and lateral plantar nerves in the foot in normals. An antidromic technique was used with stimulation at the ankle and recording from the small and large toes. Recordable responses were obtained in 149 instances. Conduction velocity in the medial branch distal to the tarsal tunnel was 40.5 +/- 4.0 m/sec and significantly slower than conduction in the lateral branch by 4.3 m/sec. The amplitude of the evoked response from the big toe was 3.46 +/- 2.2 microV and significantly larger than that in the small toe by 1.34 microV. Evoked response amplitude in the medial branch was greater in younger subjects.

Distribution of HLA class I alleles and haplotypes in Korean

The antigen (phenotype), gene (allele) and haplotype frequencies of HLA class I were analysed in 4,622 Koreans. With allele frequencies of over 0.05, the most frequent HLA-A,-B and -C antigens were A2, A24, A33, A11, A26, A31; B62, B51, B44, B54, B61, B35, B58, B60; Cw3, Cw1, Cw4, Cw7. Of these A2, A24, Cw1 and Cw3 were present in very high frequencies, respectively (0.3211, 0.2200, 0.2204, and 0.3737). The most common haplotypes with frequencies larger than 0.02 were A2-Blank, A33-B44, A33-B58, A11-B62, A24-B51, A24-B54, A2-B27, B54-Cw1, B58-Cw3, B51-Blank, B61-Cw3, B62-Cw4, B35-Cw3, B44-Blank, B60-Cw3, B27-Cw1, A2-Cw3, A2-Cw1, A24-Cw1, A33-Cw3, A26-Cw3, and A11-Cw4. A significant negative linkage disequilibrium was found for the haplotypes of A2-B7, A2-B44, A2-B58, A24-B13, A24-B27, A33-B54 and A33-B62, of which frequencies were larger than 0.003. The B-C and A-C haplotypes which showed the significant negative linkage disequilibrium were B44-Cw1, B51-Cw1, B44-Cw3,B62-Blank, A2-Cw4, A2-Blank, A11-Cw3, A11-Blank and A33-Cw1 and had frequencies higher than 0.01. The findings presented here could be used per se to estimate the populational relationships or as the control data for HLA-disease investigation. Furthermore they could provide the scope for the definition of new antigens.

Reproducibility of random amplified polymorphic DNA (RAPD) analysis among laboratories

Random amplified polymorphic DNA (RAPD) analysis appears to offer a cost- and time-effective alternative to restriction fragment-length polymorphism (RFLP) analysis. However, concerns about the ability to compare RAPD results from one laboratory to another have not been addressed effectively. DNA fragments that were amplified by five primers and shown to be reproducibly polymorphic between two oat cultivars (within the Ottawa laboratory) were tested in six other laboratories in North America. Four of the six participants amplified very few or no fragments using the Ottawa protocol. These same participants were able to generate a considerable number of amplified fragments by using their own protocols. The reproducibility of results among laboratories was affected by two factors. First, different laboratories amplified different size ranges of DNA fragments, and, consequently, small and large polymorphic fragments were not always reproduced. Second, although reproducible results were obtained with four of the primers, reproducible results were not obtained with the fifth primer, using the same reaction conditions. It is suggested that if the overall temperature profiles (especially the annealing temperature) inside the tubes are identical among the laboratories, then RAPD fragments are likely to be reproducible.

Measurement of the impulsive bone motion by skin-mounted accelerometers

A measurement system was designed to investigate longitudinal wave propagation through the lower extremity generated from foot strikes. The principal goal of the design was to eliminate measurement time lag and amplitude reduction, such that the acceleration measured by Skin Mounted Accelerometer--SMA is equal to the actual acceleration of the bone measured by Bone Mounted Accelerometer--BMA. For accurate dynamic measurement, it is important that the gain and phase of the measurement system are as close as possible to a constant and zero, respectively, for the frequency range being covered. An in vitro experiment was carried out to simultaneously measure skin and bone accelerations. The obtained information was used for identification of a linear spring/damper model representing the interface between the BMA and the SMA. The present work showed that the SMA overestimated the BMA by 12 percent in the signals between 15-30 Hz.

Vasculitis in Klinefelter's syndrome

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Contact of Rubber Wedges with a Flat Rigid Surface

Contact widths have been measured for long rubber wedges, with wedge angles ranging from 60° to 115°, pressed against a smooth, flat, rigid surface. The contact width grew rapidly at first to about 50 µm, and then more slowly, in proportion to the applied load. Thus, the mean contact pressure in the early stages of contact was small, about 5 to 10% of Young's modulus, E. It then became substantially constant at about 65% of E for a wide range of applied loads, up to about 300 N/m. Approximately the same results were obtained from FEM calculations for incompressible linearly elastic wedges with slightly rounded tips. The contact width at a given load increased slightly when the wedge was held at an angle to the vertical, up to a tilt angle of about 20°. Above this tilt angle, only one side of the wedge came into contact, and the contact width increased significantly; the mean contact pressure falling to about 0.2 E at a tilt angle of 30°.