Unscheduled CDK1 activity in G1 phase of the cell cycle triggers apoptosis in X-irradiated lymphocytic leukemia cells

Cyclin-dependent kinase 1 (CDK1) is a major component of the cell cycle progression engine. Recently, several investigations provided evidence demonstrating that unscheduled CDK1 activation may also be involved in apoptosis in cancerous cells. In this article, we demonstrate that X-ray irradiation induced G1 arrest in MOLT-4 lymphocytic leukemia cells, the arrest being accompanied by reduction in the activity of CDK2, but increased CDK1 activity and cell apoptosis in the G1 phase. Interestingly, this increase in CDK1 and apoptosis by ionizing radiation was prevented by pretreatment with the CDK1 inhibitor, roscovitine, suggesting that CDK1 kinase activity is required for radiation-induced apoptotic cell death in this model system. Furthermore, cyclin B1 and CDK1 were detected co-localizing and associating in G1 phase MOLT-4 cells, with the cellular lysates from these cells revealing a genotoxic stress-induced increase in CDK1 phosphorylation (Thr-161) and dephosphorylation (Tyr-15), as analyzed by postsorting immunoprecipitation and immunoblotting. Finally, X-irradiation was found to increase Bcl-2 phosphorylation in G1 phase cells. Taken together, these novel findings suggest that CDK1 is activated by unscheduled accumulation of cyclin B1 in G1 phase cells exposed to X-ray, and that CDK1 activation, at the wrong time and in the wrong phase, may directly or indirectly trigger a Bcl-2-dependent signaling pathway leading to apoptotic cell death in MOLT-4 cells.

Expression of adherent molecule and cyclin by ligustrazine in bone marrow of mice with immune-induced aplastic anemia

Mice with immune-induced aplastic anemia (AA) were given 5 mg ligustrazine intraperitoneally twice a day. On the 14th day, the expression of CD49d, CD49c, cyclinD2 in bone marrow mononuclear cells (MNC) was examined by flow cytometry, and VCAM-1 on stromal cells was immunohistochemically measured by Strept Avidin-Biotin Complex (SABC). The expression of CD49d, CD49c, VCAM-1 and cyclinD2 in ligustrazine-treated group was significantly higher than that in AA group (P < 0.01), but the ratio of G0 + G1 phase cells was significantly lower than that in AA group (P < 0.01). The results showed that ligustrazine could improve the expression of adherent molecule and cyclin D2 in the bone marrow of mice with immune-induced aplastic anemia, thereby promoting the growth of hematopoietic cells.

[A contour map segmentation for laser scanning confocal microscopic biomedical images]

We propose a contour map segmentation method for laser scanning confocal microscopic (LSCM) biomedical images. In this method, an image is first segmented into sub-regions by contour map. Then the sub-regions are merged from top to bottom or from bottom to top, according to a segmentation criterion of intensity homogeneity. The merging procedures continue until no region needs to be merged. The advantage of this method is that the objects with wide intensity ranges and different intensity homogeneity can be segmented properly. In this paper, the region segmentation by contour map is first addressed. Next a region merging according to a segmentation criterion of intensity homogeneity is presented, and then the design of a linear intensity homogeneity segmentation criterion is introduced. Two examples of image segmentation by this method are given at the end of this paper.

Cell cycle analysis by cyclin E + A/DNA multiparameter flow cytometry in exponential growth MOLT-4 cells

OBJECTIVE

To establish a new method for analyzing the cell cycle in tumor which is a kind of cell cycle disease.

METHODS

Mixtures of cyclin E and cyclin A antibodies were incubated with fixed MOLT-4 cells, and measured by flow cytometry.

RESULTS

We developed a cyclin E + A/DNA flow cytometry analysis method, which may distinguish G0, early G1, late G1, S, G2 and M phase cells, rather than three phases in the DNA content histogram.

CONCLUSION

Cyclin E + A/DNA multiparameter flow cytometry can simultaneously differentiate in the same sample six cell groups: G0, early G1, late G1, S, G2 and M phase cells. It performed better than any other cell cycle analysis methods that we have used and has a definite cell biology foundation.

[Green electroluminescence generated from a new rare earth complex: Tb(asprin)3phen]

Pure Green and narrow bandwidth emission from organic electroluminescent device was presented by using a new rare earth complex Tb(asprin)3phen as emissive layer. The structure of the device was ITO/PVK:Tb(asprin)3phen/Al, where PVK was used to improve the film-forming ability and conductivity of Tb(asprin)3phen. The electroluminescent property of the device was studied. It proved that this new kind of rare earth complex has excellent optoluminescent and electroluminescent properties. The electroluminescent mechanism of the device was proposed by measuring and analyzing the emission and excitation spectra of the emissive layer. The excitation spectrum of Tb(asprin)3phen-dispersed PVK film was very similar to that of the PVK. We proposed that the excited carriers of PVK and Tb(asprin)3phen were captured by Tb3+ and light was emitted when the electrons and holes recombined at Tb3+.

[Research and development of standard (DICOM) interface for digital color ultrasound system]

In this paper, the authors, who have the experience in developing DICOM interface for a digital color Doppler ultrasound system, analyze the requirements for a digital ultrasound system DICOM interface, set forth it's design and implementation using object oriented and hierarchy method. Finally, conclusion is given.

[Edge-detection and its application in medical image processing]

Edge-detection is all the time a major problem in the computer early vision, and it plays an important role in image processing. This paper reviews classical and new methods of edge-detection and discusses its application in medical image processing.

[Time for extubation and sequential noninvasive mechanical ventilation in COPD patients with exacerbated respiratory failure who received invasive ventilation]

OBJECTIVE

To discuss the optimal time for extubation and sequential non-invasive mechanical ventilation in COPD patients with exacerbated respiratory failure who received invasive ventilation.

METHODS

24 patients received invasive ventilation for 3 days were randomly assigned to receive noninvasive ventilation (study group) or to continue the weaning process with invasive ventilation (control group). The incidence of ventilator-associated pneumonia (VAP), the incidence of death, the duration of ventilation, the hospitalization were analyzed in two groups.

RESULTS

Between study group and control group, the incidence of VAP was 0/12 vs 7/12, P = 0.027; the incidence of death was 0/12 vs 3/12, P = 0.217; the continued duration of ventilation after invasive ventilation for 3 days was (7 +/- 5) days vs (15 +/- 12) days, P < 0.05; the hospitalization was (16 +/- 6) days vs (25 +/- 12) days, P < 0.05, respectively.

CONCLUSIONS

In COPD patients with exacerbated respiratory failure who received invasive ventilation, invasive ventilation for 3 days followed by noninvasive ventilation may decrease the incidence of VAP, shorten the duration of ventilation and hospitalization.

Immunophenotyping of lymphocyte T and B in the peripheral blood of systemic lupus erythematosus

The immunophenotyping expression levels of lymphocyte in the peripheral blood from 21 patients with active systemic lupus erythematosus (SLE) were analyzed by using the immunofluorescence labeling-flow cytometry technique to investigate the immunophenotyping expression of lymphocytes T and B in the peripheral blood of active SLE patients and its clinical value. It was showed that, compared with normal controls, the expression of CD3+, CD4+ and the ratio of CD4+/CD8+ in the peripheral blood of these patients were decreased (P < 0.01), while the expression of CD8+, CD20+ was significantly increased (P < 0.01). It was suggested that both T and B cells in patients with active SLE involved in immunoregulation, were activated. The abnormal expression of lymphocyte immunophenotyping could influence the immune reaction in SLE patients, which might be one of the important pathogenesis factors in SLE.

The application of CD71 and Hoechst33258 to staining method for sorting fetal nucleated red blood cells in the peripheral blood of pregnant women

OBJECTIVE

To compare mononuclear cells labeled by CD71 single-staining method with CD71 and Hoechst33258(HO258) double-staining one, and sort nucleated red blood cells (NRBCs) in peripheral blood in pregnant women by use of the latter method.

METHODS

Mononuclear cells in umbilical blood and peripheral blood in normal pregnant women and patients with mild or moderate pregnant hypertension syndrome were labeled by erythrocyte specific antibody CD71 and nuclear dye HO258. Furthermore, NRBCs were sorted in combination with the use of flow cytometry.

RESULTS

Labeled by CD71 and Hoechst33258 double-staining method, the positive labeling rate of mononuclear cells in umbilical blood and peripheral blood in normal pregnant women and patients with pregnant hypertension syndrome was remarkably lower than that labeled by CD71 single-staining method (t-test, P<0.01). Meanwhile, CD71 and Hoechst33258 double-staining method was successfully used in sorting NRBCs in peripheral blood in pregnant women by flow cytometry.

CONCLUSION

CD71 and HO258 double-staining method could exclude mature erythrocytes, thrombocytes and reticulocytes and this improve NRBCs' specific label and sorting purity.

[FTIR and fluorescence studies on the europium complexes of multiple ligands]

A series of EuA(m).nB complexes with different molar ratio of ligands and various concentrations of protecting agent were synthesized (A is thenoyltrifluoroacetone, B is a kind of P = O group compound). The properties of these complexes were investigated by FTIR and fluorescence spectroscopy. The fluorescent intensity of complex is related to the reaction condition, the components of complexes.

Effect of ligustrazine on expression of adherent molecule CD49d and cyclin D2 in hematopoietic cells in acute radiation injured mice

After irradiation by 8.0 Gy gamma-ray, each mouse was stomach-fed by 4 mg ligustrazine injection twice a day. On the 7th day after irradiation, CD49d expression in ligustrazine-treated group was significantly higher than that in control group (P < 0.01), and showed no difference from that in normal group (P > 0.05). On the 14th day after irradiation. CD49d expression was increased in control group, but decreased significantly in ligustrazine-treated group (P < 0.01). The expression of Cyclin D2 in spleen mononuclear cells (MNC) in ligustrazine-treated group was significantly higher than that in control group, but the ratio of G0 + G1 phase cells was significantly lower in ligustrazine-treated group (P < 0.01). This finding indicated that ligustrazine could increase the expression of adherent molecule on bone marrow hematopoietic cells and Cyclin D2 in spleen MNC, thereby promoting the growth of hematopoietic cells.

Study on the relationship between cytogenetics and phenotypic effect in Turner's syndrome

The cytogenetics and clinical stigmata in 5 cases of Turner's syndrome were studied. Three of them were non-mosaic 1(Xq) and two with partial monosome of a X chromosome short are (Xp21), whose DNA replication patterns of inactive X chromosome were analyzed by RBG technique. Results showed that differences between the replication patterns in cases of X chromosome deletion (Xp21) and normal females existed; that the behavior of abnormal X expressed nonrandom inactivation. It was suggested that the phenotype may be closely related with both X chromosome replication pattern and its inactivation behavior, which might be useful in genetic counselling.

[Clinical evaluation of enantone in the treatment of prostate cancer]

OBJECTIVE

In order to improve the effect of hormone treatment for prostate cancer, a total of 17 such patients were treated with Enantone(chemical castration) from July 1990 to July 1992.

METHODS

In the control group, 16 evaluable patients who were followed for 3 to 5 years, PSA was determined with ELISA. Commercial kit was used for determination of T, LH and FSH. Prostate lesion and metastasis and patient's status was eximination in the follow-up.

RESULTS

Enantone was ableto suppress plasma testosterone concentration to the condition of castration during treatment (P < 0.01). PSA and other markers also responded well. Significant improvement in performance status, micturition problems and general well-being was reported.

CONCLUSION

The once a-month administration of Enantone combined with flutamide is effective in the management of advanced prostate cancer with acceptable side-effects.

Molecular cloning of cDNA encoding the phenol/aryl form of sulfotransferase (mSTp1) from mouse liver

The cDNA sequence of the mouse liver phenol/aryl form of sulfotransferase (mSTp1) has been determined. The cloned cDNA consists of 1269 base pairs (bp) and contains an 897 nucleotide open reading frame (ORF) beginning at nucleotide 65, which encodes a 298 amino acid polypeptide of 34.7 kDa. Alignment of mSTp1 to other sulfotransferases shows overall identities of 87% to r-STp, 37% to r-STa, 48% to r-STe, 51% to b-STe, and 37% to h-STa, at the deduced amino acid level.

Molecular cloning of the alcohol/hydroxysteroid form (hSTa) of sulfotransferase from human liver

A cDNA encoding the human alcohol/hydroxysteroid sulfotransferase (h-ST-a), which catalyzes the sulfo-conjugation of many drugs and hormones, was isolated from a human liver cDNA library using a rat STa (rSTa) cDNA probe. The cDNA, designated as hSTa, consists of 1069 base pairs (bp) and contains an 855-nucleotide open reading frame beginning at nucleotide 65, which encodes a 285 amino acid polypeptide of 33.76 kDa. A second cDNA clone (1563 bp) was truncated 5' at nucleotide 231 (lacking the first 15 amino acids) with identical coding region, however, it had a much longer 3' untranslated region (UTR). Both clones contained a short segment of poly(A)+ tail. Northern blot analysis of an adult human liver showed that there are at least 2 mature mRNA with sizes ranging from approximately 1.1 kb to 1.7 kb, verifying the authenticity of the obtained cDNA clones. From the sequence alignment, the hSTa shares 62%/74%, 39%/59%, 35%/48%, 36%/54% identity with rSTa, rSTp (phenol), rSTe (estrogen), and bovine STe (bSTe) at the deduced amino acid and DNA levels, respectively, indicating that there are at least three subfamilies (alcohol, phenol and estrogen) of genes that encode for sulfotransferases in mammals.

[Studies on the mutagenicity of vesnarinone]

The mutagenicity of domestic Vesnarinone (OPC-8212) was studied by Ames test, micronucleus test of NIH mouse bone marrow and chromosome aberration assay in CHL cells. Negative results were obtained, which suggested that OPC-8212 did not induce prokaryotic cell gene mutation or chromosome damage both in vitro and in vivo.