Two-color FISH characterization of i(1q) and der(1;16) in human breast cancer cells

Two-color fluorescent in situ hybridizations using probes for alphoid (α) and classical satellite (CS) DNAs from chromosomes 1 and 16 were performed to characterize i(1q), der(1;16), and complex rearrangements observed in breast cancer cells from fresh tumors and established cell lines. Six of seven i(1q) occurred after breakage in the α1 containing region and one of seven was dicentric, with breakage in 1p11.2. The five der(1;16)(q10;p10) studied appeared to result from a variety of breakpoints involving α1, α16, CS1, and CS16 DNAs. All had conserved α16 DNA, suggesting a segregation of the der(1;16) leading to a loss of 16q and a gain of 1q in most cases. One complex rearrangement of chromosome 1 also appeared to involve chromosome 16, suggesting that a der(1;16) occurred first, followed by another rearrangement. Both the apparent preferential involvement of constitutive heterochromatin harboring α and CS DNAs and the variety of breakpoints spanning along heterochromatin suggest that the important consequence of the rearrangement is not the breakage per se but the resulting imbalance. © 1993 Wiley-Liss, Inc.     

Tissue zinc levels in precancerous tissue in the gastrointestinal tract of azoxymethane (AOM)-treated rats

Alterations in tissue zinc levels have been documented in patients with gastrointestinal tract malignancies and more frequently, in those with colonic cancer. However, the precise role of tissue zinc in carcinogenesis is not well elucidated. This study, using a well-established colon cancer model in rats, was designed to investigate the relationship of tissue zinc to the carcinogenic process. The aim was to examine tissue zinc levels in the preneoplastic tissues and to study the changes that occur during transition of mucosa from normal to preneoplastic state. Six-week old rats were given a single dose subcutaneous injection of azoxymethane (AOM) (30mg/kg body weight) and sacrificed after 1, 2, 5, and 9 months of the treatment. Plasma zinc levels showed a significant decrease (p<0.05) at 9 months compared with controls. Tissue zinc levels showed a significant decrease in the large intestine at 1 and 2 months (p<0.05) and at 5 and 9 months (p<0.01), in the small intestine at 2, 5, and 9 months (p<0.05), and in the stomach at 5 and 9 months (p<0.05). The maximum percent decrease (45%) in tissue zinc was observed in the large intestine at 9 months. Tissue copper zinc super oxide dismutase (CuZnSOD) activity was assessed in the body of the stomach, small intestine, and large intestine and compared with the control group. There was a significant fall in CuZnSOD levels in the small intestine at 9 months (p<0.05) and in the large intestine at 5 and 9 months (p<0.01). Two of these six rats showed histological evidence of precancerous lesions in the mucosa of the colon. This study suggests that the decrease in plasma zinc, tissue zinc and activity of CuZnSOD is associated with development of preneoplastic lesions in the colonic mucosa.     

Involvement of MMPs in delayed neuronal death after global ischemia

Spatial and temporal relations between metalloproteinase (MMP-2 and MMP-9) activation and laminin degradation in gerbil hippocampus after transient cerebral ischemia has been studied. Activity of MMPs was determined by gelatin zymography in homogenates from dorsal (DP, an equivalent of CA1 sector) and abdominal (AbP, containing CA2-4 and gyrus dentatus) parts of hippocampus. A significant activation of both investigated metalloproteinases was found at 72 h of recovery. Whereas MMP-2 up-regulation did not show any spatial preferences, the increase of MMP-9 activity was observed exclusively in DP. Activation of MMP-9 at this time point correlated spatially with degradation of laminin-protein of extracellular matrix. These results show that MMP pathway may function as a component of delayed neuronal death cascade in the apoptogenic CA1 sector after transient global ischemia.     

Morphometric study of the ductus arteriosus during human development

During prenatal life, the ductus arteriosus connects the left pulmonary artery and the descending aorta. Morphometric features (length, external diameter, volume) of the ductus arteriosus in 131 human fetuses (65 males, 66 females) were studied by means of anatomical, digital and statistical methods. Regression analysis was used to investigate the growth of the ductus arteriosus during gestation. The values of the length of the ductus arteriosus ranged from 3.95 mm for the 15 week gestational group to 12.20 mm for the 34th week of gestation. The length of the ductus arteriosus related to fetal age (x) increased according to the linear function y = -3.0726 + 0.4381x. The mean values of the diameter of the ductus arteriosus ranged from 1.34 to 3.49mm for the 15 and 34 week gestational groups, respectively. The growth of the ductus arteriosus diameter followed in accordance with the linear function y = 0.2072 + 0.0935x. The mean values of the ductus arteriosus volume ranged from 5.08 mm3 for the 15 week group to 117.30 mm3 of the 34 week gestation group. The volume growth increased according to the function y = 0.0007x3.3782. Positive correlation coefficients between arterial parameters and fetal age were statistically significant (P < or = 0.01) and reached the following values: r1 = 0.98 for Length, r2 = 0.90 for diameter and r3 = 0.94 for volume. Despite the increase in absolute diameter, the relative diameter of the ductus arteriosus (ductus arteriosus-to-aortic bulb diameter ratio) decreased from 0.80 to 0.48.     

Autoimmunity to Polymorphonuclears: Functional Consequences of the Binding of Antibodies to Membrane and Cytoplasmic Target Antigens of Polymorphonuclear Leukocytes

Antineutrophil autoantibodies reacting with cytoplasmic antigens are associated with various types of vasculitides, whereas antibodies reacting with neutrophil membrane antigens are mostly related to autoimmune neutropenias. The aim of this study was the investigation of the effect of monoclonal antibodies (MoAbs) reacting with surface and cytoplasmic antigens of polymorphonuclear leukocytes (PMN) known to be targets for autoantibodies in human diseases. Blood of healthy volunteers was tested for several phagocytic functions in the presence of MoAbs against surface (CD16, GD11b, CD18, NB1) and cytoplasmic (proteinase 3; PR3) molecules. Candidacidal activity was significantly inhibited in the presence of all MoAbs but isotypic control. Phagocytic activity was inhibited by anti-CD11b and/or anti-CD18 MoAbs. Zymosan-induced chemiluminescence was reduced by MoAbs anti-CD16, CD18, and NB1, enhanced by anti-PR3 MoAb, and less enhanced by anti-CD11b. In conclusion, antimembrane antibodies diminished phagocytic functions at multiple steps; in contrast, anticytoplasmic MoAb promoted activation of oxidative burst in addition to impairment of microbicidal activity. This fact may be related to different pathogenic aspects of diseases associated with antimembrane and anticytoplasmic antibodies.     

Immunocytotherapy. A new trend in fetal tissue transplantation

The clinical applications of theoretical immunology are not numerous. The authors demonstrate present-day immunocytotherapeutic approaches to fetal tissue transplantation widely used in medicine. Results of therapy by injections of lymphokine-activated killer cells in combination with interleukin-2, T-cell vaccines, and genetically transformed T cells are presented. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 4, pp. 412–415, April, 1994     

Synthesis and characterization of new siloxane-modified addition polyimides

A new series of polyimides was synthesized by addition polymerization of 4,4′-(bismaleimido)-diphenylmethane, 1,4-piperazine and an amino-terminated polydimethylsiloxane. The synthesis was carried out in m-cresol solution following a two-step procedure. Copolymers containing 15 and 20 wt.-% of the polydimethylsiloxane elastomer were prepared, together with the unmodified base copolymer. Infrared spectroscopy, ¹³C and ¹H NMR, thermal and thermogravimetric analyses were used to characterize the copolymers. The DSC curves of all the samples showed an exotherm in the temperature range 230–280°C, attributable to curing and addition reactions involving the chain-end groups. Different glass transition temperatures (T_g) were observed, depending on the elastomer content. Thermogravimetric analysis indicated that no significant changes occur in the thermal stability of rubber-modified copolymers.     

Pathophysiological mechanisms of torsion dystonia

Sixty-three patients were subjected to clinico-electrophysiological examination for precise definition of the features of pathogenesis of the tonic and clonic forms of generalized torsion dystonia. Stimulation electromyography was conducted by the generally accepted method with determination of the composition of motor neurons involved in the reflex response. Torsion dystonia was found to be a pathogenetically heterogeneous disease. Registration of the motor neurons involved in the reflex response yielded additional information on the pathogenetic features of this disease.