Evaluation of serum-associated embryotoxicity/mutagenicity in females with reproductive dysfunctions using preimplantation mouse embryos in vitro

Reproductive failures may be caused by chromosomal anomalies, complex interactions of maternal/fetal genotype and environmental factors. Some of them have also been attributed to undefined maternal serum factor(s). We have developed an assay to evaluate maternal-serum associated embryotoxicity/mutagenicity using the preimplantation mouse embryo. It is based on in vitro culture of 8-cell mouse embryos for 48 h in the presence of 10% sera from females with reproductive dysfunction along with suitable controls. The human sera were obtained from three groups of females: (i) with normal reproductive histories (negative controls), (ii) undergoing cancer chemotherapy (positive controls), and (iii) with a history of failing to achieve or maintain pregnancy (test group). The preimplantation mouse embryos were cultured in the three types of human sera and female rat serum (as an internal control for each experiment) and evaluated for toxicity (embryo survival) and mutagenicity (as measured by SCE). Embryos cultured in serum from women with normal reproductive histories and female rats had survival rates of 70.8 +/- 4.3 and 78.9 +/- 0.9%, respectively. The SCE frequencies for these two sera types were similar: 15.7 +/- 0.2 SCEs/cell (rat) and 16.3 +/- 0.3 SCEs/cell (human). Mouse embryos cultured in medium supplemented with serum from females undergoing chemotherapy had significantly (P less than 0.01) reduced survival (33.7 +/- 5.2%) and significantly (P less than 0.01) increased SCEs/cell (26.5 +/- 0.6). The effect of sera from women with histories of reproductive failures on preimplantation mouse embryos was variable and individual specific. Approximately 40% of the test group female sera yielded survival and SCEs/cell comparable to the sera from patients undergoing chemotherapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Synthesis and secretion of immunoglobulin G by lymphocytes from cultured mouse spleen cells is not affected by heat shock

Short-term hyperthermic episodes (in vivo and in vitro) alter gene expression in mammalian lymphocytes, resulting in the enhanced synthesis of a select group of polypeptides--the heat-shock proteins--and the depressed synthesis of many normally synthesized polypeptides. Such alterations could have profound implications to an individual if the appropriate functioning of lymphocytes within the immune response was compromised by a depression in immunoglobulin synthesis during naturally occurring periods of hyperthermia, such as fever. In the present study we asked if heat-shock affects the facultative synthesis and secretion of immunoglobulin G by cultured mouse lymphocytes. We found that the quantity of immunoglobulin G synthesized and secreted by these cells is not affected by heat-shock treatments sufficient to induce the synthesis of heat-shock proteins.

The synergistic effect of hyperthermia and ethanol on changing gene expression of mouse lymphocytes

Cultured mouse lymphocytes respond to a brief incubation at an elevated temperature (41-43 degrees C) with the new and (or) enhanced synthesis of a select group of polypeptides (known as heat-shock proteins, HSPs) having relative molecular masses of 110, 100, 90, 70, and 65 kilodaltons (kDa). Expression of these HSPs is dependent on new RNA synthesis. Because the synthesis of any particular HSP is dependent on the temperature and the length of time cells remain at a particular elevated temperature, synthesis of each HSP is not necessarily coordinated with the synthesis of the other HSPs. Cultured mouse lymphocytes treated with arsenite or ethanol exhibit new and (or) enhanced synthesis of HSPs with molecular masses of 110, 90, 70, and 65 kDa but do not exhibit enhanced synthesis of the 100-kDa HSP. Short-term concurrent exposure of mouse lymphocytes to an elevated temperature and a level of ethanol, which individually do not induce detectable HSP synthesis, results in the pronounced synthesis of HSPs similar to those seen following exposure to higher levels of either stress applied separately. Thus, in this study we demonstrate that hyperthermia and ethanol stress can act synergistically to affect a dramatic change in the gene expression of mouse lymphocytes.

Mammalian lymphocytes: stress-induced synthesis of heat-shock proteins in vitro and in vivo

Mammalian (human, mouse, and rabbit) white blood cells (lymphocytes) maintained in culture respond to a brief incubation at an elevated temperature (at or above 41 degrees C) by (i) the new and (or) enhanced synthesis of a small number of proteins (the so-called heat-shock proteins; HSPs) having molecular masses of approximately 110 000, 100 000, 90 000, 70 000, 65 000, and 26 000 daltons and (ii) the depressed synthesis of proteins normally made at 37 degrees C. The HSPs synthesized in culture by human, rabbit, and mouse (peripheral and splenic) lymphocytes are similar in number, molecular mass, and distribution on two-dimensional (isoelectric focusing and sodium dodecyl sulfate--polyacrylamide) electrophoretic gels to those synthesized in vivo by lymphocytes in hyperthermic mice. Since the level of hyperthermia used to induce HSP synthesis in mouse lymphocytes in vitro and in vivo is of a magnitude (41 degrees C) also used to promote thermotolerance in mice and is similar to temperatures attained during febrile episodes in rabbits and in humans, we suggest that the in vitro and in vivo synthesis of HSPs by mouse lymphocytes, demonstrated in this study, represents a relevant, physiological response which mammalian lymphocytes may normally use to survive periods of thermal stress.

Partial trisomy 9q resulting from a familial translocation t(9;16)(q32;q24)

Partial Trisomy- 9q was observed in an infant with a multiple malformation syndrome who survived to 18 months. Cytogenetic investigations stimulated by the family history of similarly affected individuals revealed a translocation, t(9;16)(q32;q24), identifiable in four generations of the proband's family. A review of our cases with those reported in the literature reveals clinical similarities. This report sets forth a clinical description of the characteristic phenotype of the 9q partial Trisomy syndrome, including findings at post-mortem, documents multigeneration transmission and discusses this syndrome's clinical overlap with other malformation syndromes.

Congenital hydranencephaly/porencephaly due to vascular disruption in monozygotic twins

Monozygotic twinning has been associated with a variety of vascular disruptive defects including congenital hydranencephaly/porencephaly. Data involving 24 cases of congenital hydranencephaly/porencephaly associated with twinning are reported. In these cases, the finding of a preponderance of monozygotic twins and the common association of a deceased co-twin support the hypothesis of a vascular disruptive etiology. These defects are presumed to be secondary to embolic phenomena or thromboplastin release from the deceased co-twin to the survivor via the vascular interconnections of a conjoined monochorionic placenta. In all cases of hydranencephaly/porencephaly, a careful examination of the placenta and membranes for evidence of a deceased co-twin is warranted prior to providing recurrence risk counseling.

[Aspects of surgical management of choanal atresia (author's transl)]

The indication for surgery of choanal atresia appears not uniform. In newborns the bilateral choanal atresia should be operated in the first days or weeks on account of threatening life complications. Unilateral atresia can be managed between the 3rd to 5th year; until this time the topographic conditions are enlarged nearly twice, which means much better conditions for operation. In the checked up cases (27 patients) the rate of relapse of the different surgical methods are explained. On account of a better view over the operating area and optimal plastic-surgical supply the transpalatinal approach is preferred especially in newborns and infants under microsurgical conditions and a description of the technique is given.

Identification of a complex chromosome rearrangement in Neurospora crassa

A complex chromosome rearrangement has been identified using predominantly genetic, but some cytological criteria, in crosses heterozyous for the rearrangement. The rearrangement involves the insertion of a segment of LG I into LG IV in an inverted position with respect to centromere, and a segment of LG IV reciprocally inserted into LG I, possibly in inverted sequence, T (I → IV, I ← IV). Some of the properties of such a rearrangement are considered, including absence of single exchanges in inverted segments, high incidence of even-numbered exchanges, inter-linkage group linkages, and ascospore abortion and genotype patterns; a good fit of the model to the data is demonstrated.