Trisomy 8 as the sole chromosomal aberration in myelocytic malignancies: a multicolor and locus-specific fluorescence in situ hybridization study

Trisomy 8 is the most common chromosomal aberration in myelocytic malignancies, occurring both as a sole change as well as in addition to other abnormalities. In spite of this, next to nothing is known about its pathogenetic importance or its molecular genetic consequences. Possible mechanisms involved in the transformation process include dosage effects of genes mapping to chromosome 8 and presence of specific mutations or cryptic fusion genes on the duplicated chromosome. In the latter case, +8 would be secondary to a cryptic primary rearrangement and not involved in leukemogenesis as such, but rather in tumor evolution. Although hidden genetic changes have been found in some trisomies, for example, mutations in KIT in acute myelocytic leukemia (AML) with +4 and in MET in hereditary papillary kidney carcinoma with trisomy 7, none associated with +8 have so far been discovered. To address this issue, we have investigated a total of 13 cases of AML, myelodysplastic syndromes, and chronic myeloproliferative disorders with trisomy 8 as the sole chromosomal anomaly. All cases were studied by combined binary ratio multicolor fluorescence in situ hybridization (FISH) and with FISH using locus-specific probes for both arms of chromosome 8, the subtelomeric regions of 8p and 8q, and the leukemia-associated genes FGFR1, MOZ, ETO, and MYC. No cryptic changes were detected, thus excluding the possibility of gross genetic rearrangements or aberrations involving these loci on chromosome 8.     

Particle agglutination assays for rapid detection of fibronectin, fibrinogen, and collagen receptors on Staphylococcus aureus.

Latex beads (0.8-micron diameter; Difco Laboratories) were coated with fibronectin, fibrinogen, collagen type I, or denatured collagen (gelatin) and evaluated in a particle agglutination assay (PAA) for the rapid detection of fibronectin, fibrinogen, or collagen binding to Staphylococcus aureus. These assays were compared with a commercial test for detecting the binding of fibrinogen and immunoglobulin G (Staphaurex). Bacterial cells (approximately 10(10) cells per ml) suspended in 0.02 M potassium phosphate buffer (pH 6.8) caused the clumping of standard fibronectin, collagen, gelatin, and fibrinogen latex suspensions within 2 min on glass slides. The test results were scored semiquantitatively from strongly positive ( ) to weakly positive (+) and negative (-) reactions. The negative PAA reactions corresponded to a median value of 11.5% relative to the binding of 125I-labeled protein to strain Cowan 1, indicating the high sensitivity of the test. The reactions with fibronectin and fibrinogen latex suspensions and with Staphaurex were optimal for cells grown on tryptic soy and brain heart infusion broth media. Blood agar was optimal for reactions with collagen and gelatin latex suspensions. Media containing high salts (mannitol salt agar and staphylococcus medium 110) enhanced the tendency of cells to autoaggregate. These assays were also clinically evaluated on 187 S. aureus isolates. The PAA reagents were stable, and the assays were highly specific, sensitive, and reproducible, thus making PAA suitable for the rapid screening of the binding of various bacterial pathogens to serum and connective-tissue proteins.     

Episodic variations of prolactin, thyroid-stimulating hormone, luteinizing hormone, melatonin and cortisol in infertile women with subclinical hypothyroidism

Preliminary data have suggested that female infertility due to corpus luteum insufficiency may be caused by subclinical hypothyroidism [exaggerated thyroid-stimulating hormone (TSH) response to thyrotrophin- releasing hormone (TRH) stimulation]. L-Thyroxine supplementation has been recommended to achieve pregnancies in subclinical hypothyroid women. This controlled study was carried out in order to investigate the biochemical diagnosis of subclinical hypothyroidism as a possible infertility factor. Five infertile patients (aged 25-36 years) with subclinical hypothyroidism (n = 4, stimulated TSH >20 microU/ml) or primary hypothyroidism (n = 1) and five healthy controls (aged 22-39 years) with normal thyroid function (stimulated TSH <15 microU/ml), regular cycles and no history of infertility were studied in the early follicular phase. In the pre-study evaluation, eight of 23 volunteers (34.8%) had to be excluded because of subclinical hypothyroidism with stimulated TSH values (TSHs) >15 microU/ml. Cycle function of patients and controls was compared by the method of LH pulse pattern analysis. Therefore blood samples were drawn every 10 min during a 24 h period. Sleep was recorded from midnight to 7 a.m. Repetition of the TRH tests at the end of the 24 h blood sampling period confirmed the difference in stimulated TSH values of the two study groups. Pulse analysis for luteinizing hormone (LH), TSH and prolactin showed no differences between patients and controls for pulse frequency, amplitude, height, length, area under curve (AUC) and the 24 h mean. Even the hypothyroid patient had a normal LH pulse pattern. Additional measurement of melatonin in pooled sera every 30 min gave the well-documented diurnal profiles during day and night for both groups. Patients had significantly higher melatonin values at seven time points during the night. Peaks for LH, TSH, prolactin and cortisol were correlated with the sleep stages wake, rapid eye movement, 1 + 2 and 3 + 4. We concluded that corpus luteum insufficiency in female infertility cannot be explained by subclinical hypothyroidism and thus should not be treated with L-thyroxine for fertility reasons.