Gender stress: a preliminary survey with specific reference to female physicians

Practicing female physicians in Trinidad and Tobago were studied to identify major causal factors of negative stress. Results indicated that major stressors were as follows: job (36%), finance (32%), children (20%), relationships (20%). The minor stressors identified were: children (48%), finance (36%), relationships (36%), job (32%), and health (20%). The physicians showed the ability to cope with the stress and this was attributed to, inter alia, self-sufficiency, empowerment, self-fulfillment and gender.

Human somatostatin receptor genes: localization of SSTR5 to human chromosome 20p11.2

The gene encoding the somatostatin receptor subtype designated as SSTR5 was mapped to human chromosome 20p11.2 by using fluorescence in situ hybridization to metaphase chromosomes. Fluorescence in situ hybridization using a probe for SSTR5 in combination with probes for neuroendocrine convertase-2 (NEC2), thrombomodulin (THBD), and brain glycogen phosphorylase (PYGB) established a physical order for these loci of 20pter-NEC2-SSTR5-THBD-PYGB-cen.

Variability of 11q23 rearrangements in hematopoietic cell lines identified with fluorescence in situ hybridization

We mapped and ordered 17 cosmid, phage, and plasmid clones to chromosome 11, bands q22-q24, using fluorescence in situ hybridization (FISH). We then analyzed four hematopoietic cell lines with 11q23 rearrangements, Karpas 45, SUP-T13, RC-K8, and Karpas 422, using these probes. The studies showed that the translocation breakpoints of the Karpas 45 and SUP-T13 cell lines, which were derived from T-cell malignancies, were located in the same breakpoint cluster region of the MLL gene as the RS4; 11 cell line and patients with the t(9;11), t(11;19), and t(6;11) described previously. We confirmed that the translocation breakpoint of the RC-K8 cell line was located telomeric to the MLL gene, and found that the derivative 11 chromosome of the Karpas 422 cell line, which had been thought to contain a t(4;11) (q21;q23), was in fact formed through a deletion and an inverted tandem repeat of part of 11q.

Fluorescence in situ hybridization: a sensitive method for trisomy 8 detection in bone marrow specimens

Trisomy 8 is a common anomaly in bone marrow (BM) cells of patients with myeloproliferative disorders (MPD), myelodysplastic syndromes (MDS), or acute nonlymphocytic leukemia (ANLL). We studied the efficacy of fluorescence in situ hybridization (FISH) detection of trisomy 8 in patients with MPD, MDS, or ANLL using directly labeled fluorescent alpha-satellite and whole chromosome paint (WCP) DNA probes specific for chromosome 8. Using FISH, we analyzed interphase nuclei and metaphase spreads from randomized series of BM specimens from normal individuals and patients with varying proportions of trisomy 8 as determined by conventional cytogenetic analysis. The BM of all normal donors contained less than or equal to 2.0% nuclei with 3 interphase FISH signals and less than or equal to 1 metaphase with 3 WCP FISH signals. Ninety-five percent and 98% of BM specimens with at least two metaphase cells with trisomy 8 by cytogenetic analysis contained greater than 2.0% nuclei with 3 interphase FISH and greater than 2 metaphases with 3 WCP FISH signals, respectively. Thirteen patients had 1 in 20 or 1 in 30 metaphase cells with trisomy 8 by conventional cytogenetic studies. Of these patients, four had greater than 2.0% nuclei with 3 interphase FISH signals. The BM of all four patients contained positive metaphase FISH results. We then studied the usefulness of FISH analysis to detect occult trisomy 8 by analyzing BM nuclei from 144 patients who had MPD, MDS, or ANLL and either 20 normal metaphase cells or an abnormal karyotype without trisomy 8. Seven patients had greater than 2.0% nuclei with 3 interphase FISH signals (range, 2.10% to 3.40%) and six patients had 2 or more cells with trisomy 8 upon metaphase FISH or extensive conventional cytogenetic analysis. Our results show that interphase and metaphase FISH analyses are useful methods to detect trisomy 8 cells in BM specimens, especially for specimens with normal or uncertain conventional cytogenetic results.

Der(5)t(5;7)(q11.2;p11.2): a new recurring abnormality in malignant myeloid disorders

Complete or partial monosomy for the long arm of chromosomes 5 and/or 7 is frequently observed in malignant cells from patients with a therapy-related myelodysplastic syndrome (t-MDS) or therapy-related acute nonlymphocytic leukemia (t-ANLL). Partial monosomy is usually the result of a chromosomal deletion; however, unbalanced translocations have also been observed. We have identified one such translocation in three patients who had either t-ANLL or a primary MDS. The genetic consequences of this translocation [-5,-7,+der(5)t(5;7)(q11.2;p11.2)] are partial monosomy for the long arm of chromosome 5 and complete monosomy for the long arm of chromosome 7. Thus, this rearrangement may represent a new, recurring abnormality that is associated with malignant myeloid disorders.

Variant translocations (9;11): identification of the critical genetic rearrangement

The t(9;11)(p22;q23) is a recurring abnormality in acute nonlymphocytic leukemia. The analysis of complex 9;11 translocations will aid in the identification of the conserved chromosomal junction or the critical genetic alteration created by the rearrangement; however, variant translocations involving chromosomes #9 and #11 have not been reported. We have identified such variants in two patients who had acute myelomonocytic leukemia and acute monocytic leukemia, characterized by a t(9;11;18)(p22;q23;q12) and a t(9;11;13)(p22;q23;q34), respectively. The conserved junction resulting from these rearrangements is created by the translocation of chromosomal material from 9p to 11q.

Clinical and cytogenetic correlations in 63 patients with therapy-related myelodysplastic syndromes and acute nonlymphocytic leukemia: further evidence for characteristic abnormalities of chromosomes no. 5 and 7

Clinical, histologic, and cytogenetic features in 63 patients with a therapy-related myelodysplastic syndrome (t-MDS) or acute nonlymphocytic leukemia (t-ANLL) following cytotoxic chemotherapy or radiotherapy for a previous disease were analyzed. Eleven patients had received only radiotherapy for the primary disorder. In most cases, high doses had been administered to treatment ports that included the pelvic or spinal bone marrow. Twenty-one patients had received only chemotherapy for their primary disease, all for more than 1 year and all but one with an alkylating agent, either alone or in combination with other drugs. Thirty-one patients had received both radiotherapy and chemotherapy, either concurrently or sequentially. A clonal chromosomal abnormality was observed in marrow or blood cells from 61 of the 63 patients (97%). Fifty-five patients (87%) had a clonal abnormality of chromosomes no. 5 and/or 7 consisting of loss of all or part of the long arm of the chromosome. The critical chromosome region that was consistently deleted in all 17 patients with del(5q) comprised bands q23 to q32. In addition to nos. 5 and 7, five other chromosomes (no. 1, 4, 12, 14, and 18) were found to be nonrandomly involved. Both t-MDS and t-ANLL are late complications of cytotoxic therapies that have distinctive clinical and histologic features and are associated with characteristic aberrations of chromosomes no. 5 and 7. It seems likely that these two chromosomes contain genes involved in the pathogenesis of these hematopoietic neoplasms.

Urinary 3-methylhistidine/creatinine ratio as a clinical tool: correlation between 3-methylhistidine excretion and metabolic and clinical states in healthy and stressed premature infants

We have investigated the role of the urinary 3-methylhistidine (3MH) excretion, a measure of protein catabolism, in the evaluation of the metabolic state of premature infants. Two-hundred and twenty-two 24 hr urine collections and 3MH/Cr ratio determinations (expressed as mumoles of 3MH per mg creatinine) were carried out in 36 infants (average gestational age 32.7 +/- 0.7 wk, weight 1640 +/- 120 grams) and the relationship between the 3MH/Cr ratios and the metabolic and clinical state has been investigated. Five or more 3MH/Cr measurements were carried out on each of 19 infants and serial determinations on four of those babies are presented. The urinary 3MH/Cr ratio of healthy infants with adequate caloric intake and normal growth curve was .148 +/- .039 (S.D.) mumol/mg, about 35% higher than the 3MH/Cr ratio in healthy adults. As long as the premature infants were healthy the degree of prematurity had no effect on the 3MH/Cr ratio. The relationship between 3MH/Cr ratio and nitrogen balance was highly significant (p less than .001). 3MH/Cr ratio also correlates very well with the metabolic status of the infants: in the group with normal 3MH/Cr ratios less than or equal to .175 (.148 + 1 S.D., n = 90) there were four clinically stressed infants (4.4% false negative rate) while in the group with elevated 3MH/Cr ratios greater than .225 (.148 + 2 S.D.; n = 79) there were only three clinically well infants (3.8% false positive rate). In comparing the clinical status and 3MH/Cr ratios, we found that in the group of infants who could not be clearly defined as clinically well or stressed (n = 108) the 3MH/Cr ratio was more useful than clinical judgment in the prediction of metabolic status. It can be concluded that 3MH/Cr ratio is a potentially useful clinical tool which describes with high accuracy the clinical and metabolic status of premature infants. This conclusion is further supported by the data of serial 3MH/Cr determinations.

Significance of cell-to cell contacts for the directional movement of neural crest cells within a hydrated collagen lattice

Neural tubes whose neural crest had just begun migration were isolated from stage-14 chick embryos, cleaned with 0.1% trypsin, and cultured in transparent hydrated collagen lattices (HCL) in an effect to stimulate in part the three-dimensional environment through which neural crest cells migrate in situ, in the embryo. The concentration of collagen in the lattices varied from 50 microgram/ml to 390 microgram/ml. The mode of movement and contact behaviour of neural crest cells migrating from the neural tube under these conditions were recorded directly with time-lapse cinemicrography. Both their shape and their rate of translocation were dependent on the concentration of collagen in the HCL. In low concentrations (50 microgram/ml to 105 microgram/ml), neural crest cells have elongate spindle shapes and translocate at an average rate of 1 micrometer/min, whereas in high concentrations (190 microgram/ml to 390 microgram/ml), their shape is rounded, and they translocate at an average rate of only 0-5 micrometer/min. Neural crest cells migrate from neural tubes in these preparations principally in loose clusters, with a few single cells in the lead. The cells in these groups display leading-to-trailing edge adhesions and form tongues or streams of cells directed away from the neural tube. The paths of migration of both individual cells and groups of cells are aligned with the collagen fibrils of the HCL, which radiate from the neural tube. The classical visible characteristic of contact inhibition of movement, change in direction of cell movement after contact with other cells, was not observed; neither the rate of translocation nor the time spent migrating away from the tube is dependent on the number of contacts between cells. It is concluded that the directional movement of neural crest cells in HCL cultures does not depend on contact inhibition of movement.

Urinary 3-methylhistidine excretion and nitrogen balance in healthy and stressed premature infants

Conventional methods of assessing adequate nutrition in children may be inaccurate or change too slowly to be helpful during acute illness. Techniques to measure protein synthesis or breakdown provide more accurate information. Three-methylhistidine (3MH), an unusual amino acid found in actin and myosin, is not further metabolized and is quantitatively excreted following muscle degradation. Urinary excretion of 3MH has, therefore, been proposed as a marker of protein catabolism. The ratio of 3MH to creatinine in 24-hr urine collectons was studied in 14 healthy or stressed premature infants, and compared to nitrogen balance (N bal), caloric intake and clinical course. There is a significant inverse correlation between 3MH/Cr ratio and N Bal (R = -.507). The mean 3MH/Cr ratio was 0.140 +/- 0.037 mu mole/mg (n = 37) in healthy growing premature infants and 0.296 +/- 0.160 (n = 26) in infants who were stressed and/or had inadequate nutrient intake. Healthy growing infants almost invariably had a ratio below 0.200. Serial determinations in three infants consistently showed a rise in the ratio to above 0.200 during periods of stress or decreased intake. The 3MH/Cr ratio may be a more sensitive indicator of metabolic status and may be useful clinically, especially in infants receiving total parenteral nutrition.

Translocation of neural crest cells within a hydrated collagen lattice

Chick neural tubes were cultured either on planar substrata of collagen-coated Falcon plastic in growth medium with serum or within a hydrated collagen lattice (HCL) in growth medium either with or without serum. Using time-lapse cinemicrography, neural crest cells were observed emigrating from neural tubes over the collagen substrata. Once separated from the neural tube, they seldom reunite with it. Though the average rate at which the neural crest cells translocate was the same in the different culture conditions, approximately 1.0 micron/min, distinct differences in morphology and mode of translocation were observed. Neural crest cells on collagen-coated culture dishes have a flattened fibroblastic morphology and mode of translocation; in an HCl with serum, they have a bipolar shape and translocate by advancing a long, narrow leading protrusion and by periodically retracting the attenuated trailing portion of the cell; and in a serum-free HCL, they have a unipolar shape and translocate by advancing a long, narrow, branched leading protrusion and by periodically transferring the cytoplasm of the large, rounded trailing cell body forward, past a bulbous structure, and into the leading protrusion.

Myxosoma cerebralis: Detection of Circulating Antibodies in Infected Rainbow Trout (Salmo gairdneri)

Circulating antibody against spores of Myxosoma cerebralis has been detected for the first time in rainbow trout (Salmo gairdneri) affected with whirling disease. An indirect fluorescent antibody test (IFAT) was employed for detection of trout immunoglobulin. Most sera of fish from an infected experimental group were found to give a positive reaction in the IFAT, while the majority of specific-pathogen-free control sera gave no reaction. Reagent preparation as well as staining and evaluation procedures are given. These results provide additional information for understanding the host/parasite relationship and offer a potential for development of a nondestructive serological test for whirling disease. Key words: indirect fluorescent antibody test, immune response, whirling disease