[Analysis of cervical cancer screening results in women aged 50 and older in Beijing and Guizhou].

Objective: To analyze the screening results of cervical cancer in elderly women in Beijing and Guizhou. To compare the screening effectiveness of cervical cancer in elderly women in different areas. Methods: A retrospective analysis was performed on the screening data of elderly women (≥50 years) who had examination at cervical lesion clinic in Peking University People's Hospital and Affiliated Hospital of Guizhou Medical University from January 2013 to January 2014, with histopathology as the gold standard, to compare screening effectiveness of cervical cytology or HPV detection for elderly women in cervical cancer screening in the two regions. Results: Among the patients with cervical intraepithelial neoplasia grade 2 and above (CIN2 + ) detected by colposcopy in Peking University People's Hospital and Affiliated Hospital of Guizhou Medical University, 44.1% (82/186) and 57.0% (98/172) were women aged 50 and older. In Beijing group 39.0% (32/82) of CIN2 + patients had clinical symptoms, which in Guizhou group was 31.6% (31/98). In Beijing group and Guizhou group, 50.0% (19/38) and 73.2% (30/41) patients with cervical cancer had never been screened, respectively. In Beijing group and Guizhou group, 5.4% (4/74) and 19.2% (10/52) of the patients with CIN2 + had cervical cytology negative for intraepithelial lesion or malignancy (NILM), respectively (P=0.015). The cervical cytology showed atypical squamous cells of undetermined significance (ASC-US) in 10.2% (13/127) and 24.6% (14/57), respectively, with significant difference (P=0.01). The cervical cytology showed low-grade squamous intraepithelial lesions (LSIL) in 14.9% (11/74) and 37.5% (6/16) with no significant difference (P=0.08). Atypical squamous cells cannot exclude high-grade squamous intraepithelial lesions (ASC-H) were 41.7% (5/12) and 71.4% (20/28) with no statistically significant difference (P=0.15). High-grade squamous intraepithelial lesions (HSIL) were 78.9% (15/19) and 86.4% (19/22) with no significant difference (P=0.83). In cases with HPV detection information, the sensitivity of CIN2+ diagnosis by high-risk HPV detection in Beijing group and Guizhou group was 95.2% (40/42) and 73.6% (39/53) that was statistically significant (P<0.05). Conclusions: In both Beijing and Guizhou, the incidence of CIN2+ in elderly women is at a relatively high level. There were differences in the detection of CIN2+ by cervical cytology or HPV detection in Beijing and Guizhou.

Molecular identification of the first local dengue fever outbreak in Shenzhen city, China: a potential imported vertical transmission from Southeast Asia?

A suspected dengue fever outbreak occurred in 2010 at a solitary construction site in Shenzhen city, China. To investigate this epidemic, we used serological, molecular biological, and bioinformatics techniques. Of nine serum samples from suspected patients, we detected seven positive for dengue virus (DENV) antibodies, eight for DENV-1 RNA, and three containing live viruses. The isolated virus, SZ1029 strain, was sequenced and confirmed as DENV-1, showing the highest E-gene homology to D1/Malaysia/36000/05 and SG(EHI)DED142808 strains recently reported in Southeast Asia. Further phylogenetic tree analysis confirmed their close relationship. At the epidemic site, we also detected 14 asymptomatic co-workers (out of 291) positive for DENV antibody, and DENV-1-positive mosquitoes. Thus, we concluded that DENV-1 caused the first local dengue fever outbreak in Shenzhen. Because no imported case was identified, the molecular fingerprints of the SZ1029 strain suggest this outbreak may be due to vertical transmission imported from Southeast Asia.

Effects of SN-38 (an active metabolite of CPT-11) on responses of human and rodent cells to irradiation.

PURPOSE: Modulators of the DNA-unwinding enzyme, topoisomerase I (Topo I), inhibit DNA repair and have been reported to increase the lethal effects of X rays, which create breaks in DNA. CPT-11 is a derivative of camptothecin, a Topo I inhibitor, and is clinically available. In this study, we tested the in vitro combination effects of SN-38, an active form of CPT-11, and irradiation on several cell lines. MATERIALS AND METHODS: Exponentially growing or confluent cultures of CHO cells were treated with SN-38 for 30 min. Cells were then irradiated. Thereafter, the cells were further incubated with the drug for 0 to 3 h. Exponentially growing other cell lines were exposed to 200 nM SN-38 for 30 min before, during, and 3 h after irradiation. The cell survival rate was determined using a conventional clonogenic assay. RESULTS: SN-38 (200 nM to 4 microM) alone showed slight toxicity to CHO cells in the confluent culture after a 3.5-h incubation. When the cells were treated with the lower doses of SN-38 (50 to 800 nM) during the exponentially growing phase, the cell survival rates were much lower. In combination with irradiation, SN-38 showed only additive effects to irradiation when cells were treated in confluent cultures. However, higher combination effects of SN-38 and irradiation were observed in the cells treated in the exponentially growing phase. When cells were irradiated during the exponentially growing phase, a significant combination effect of 200 nM SN-38 and irradiation was also observed in some cell lines, but not in others. CONCLUSION: SN-38 and irradiation showed supraadditive effects in some cell lines, when treated in the exponentially growing phase, but not in other cell lines or when cells were treated in the confluent phase.

A significant correlation between clonogenic radiosensitivity and the simultaneous assessment of micronucleus and apoptotic cell frequencies.

PURPOSE: To study the relationship between clonogenic radiosensitivity and a simultaneous assessment of the percentages of radiation-induced micronuclei (MN) and apoptotic cells. MATERIALS AND METHODS: Five mammalian cell lines were studied. Following irradiation, measurements were made of the percentages of MN, apoptotic cells and floating cells. Each factor was compared, both alone and as the simple sum of the factors, with cell survival. The factors were also evaluated using a multiple linear regression analysis. RESULTS: The simple sum of the MN and apoptotic cell percentages, the sum of the MN and floating cell percentages, and the sum of all three factors correlated with cell survival. However, the multiple linear regression analysis was the best method of predicting cell survival. CONCLUSIONS: These results suggest the usefulness of the simultaneous assessment of the MN frequency and the detection of floating cells in culture medium or apoptotic cells among attached cells to predict cellular intrinsic radiosensitivity. In order to predict cell survival after irradiation from these factors, the use of multivariate analyses is more useful than simple summation.

Simultaneous evaluation of radiation-induced apoptosis and micronuclei in five cell lines.

PURPOSE: This study was conducted to clarify the relationship among the frequencies of micronuclei (MN) and apoptosis, and clonogenic cell survival after irradiation. MATERIALS AND METHODS: The frequencies of MN and apoptosis were compared in the surviving fraction in three human tumour cell lines and two rodent cell lines at various irradiation doses. RESULTS: The SHIN-3, DU-145 and CHO-K1 cells showed dose-dependent increases of MN per binucleate cell and an excellent correlation between the MN frequency and surviving fraction after irradiation. The F9 and COLO 320DM cells did not show this correlation. The number of apoptotic cells increased according to the increase in radiation dose in the F9 and COLO 320DM cells, but not in the SHIN-3, DU-145 or CHO-K1 cells. CONCLUSIONS: The detection of the MN frequency alone is insufficient to measure cellular intrinsic radiosensitivity. The simultaneous use of the MN assay and the detection of apoptotic cells would be more reliable as a method for predicting cell survival after radiation.

Effect of Electromagnetic Pulses (EMP) on associative learning in mice and a preliminary study of mechanism.

PURPOSE: To investigate the effects of electromagnetic pulses (EMP) on associative learning in mice and test a preliminary mechanism for these effects. MATERIALS AND METHODS: A tapered parallel plate gigahertz transverse electromagnetic (GTEM) cell with a flared rectangular coaxial transmission line was used to expose male BALB/c mice to EMP (peak-intensity 400 kV/m, rise-time 10 ns, pulse-width 350 ns, 0.5 Hz and total 200 pulses). Concurrent sham-exposed mice were used as a control. Associative learning, oxidative stress in the brain, serum chemistry and the protective action of tocopherol monoglucoside (TMG) in mice were measured, respectively. RESULTS: (1) Twelve hour and 1 day post EMP exposure associative learning was reduced significantly compared with sham control (p<0.05) but recovered at 2 d post EMP exposure. (2) Compared with the sham control, lipid peroxidation of brain tissue and chemiluminescence (CL) intensity increased significantly (p<0.05), while the activity of the antioxidant enzymes Superoxide Dismutase [SOD], Glutathione [GSH], Glutathione Peroxidase [GSH-Px], Catalase [CAT]) decreased significantly (p<0.05) at 3 h, 6 h, 12 h and 1 d post EMP exposure. All these parameters recovered at 2 d post EMP exposure. (3) No significant differences between the sham control group and EMP exposed group were observed in serum cholesterol and triglycerides. (4) Pretreatment of mice with TMG showed protective effects to EMP exposure. CONCLUSIONS: EMP exposure significantly decreased associative learning in mice and TMG acted as an effective protective agent from EMP exposure. This mechanism could involve an increase of oxidative stress in brain by EMP exposure.

The effects of electromagnetic pulses (EMP) on the bioactivity of insulin and a preliminary study of mechanism.

PURPOSE: To investigate the effects of electromagnetic pulse (EMP) exposure on the bioactivity of insulin and a preliminary mechanism for these effects. MATERIALS AND METHODS: A tapered parallel plate Gigahertz Transverse Electromagnetic (GTEM) cell with a flared rectangular coaxial transmission line was used to expose the insulin solution to EMP. Concurrent sham-exposed insulin solutions were used as a control. The effect of EMP-exposed insulin on fasting blood glucose levels of type I diabetes model mice, the effect of EMP on binding affinity between insulin and its receptor and the effect of EMP on insulin's fluorescence intensity were detected, respectively. RESULTS: (i) After EMP exposure, compared with sham-exposed insulin, the bioactivity of insulin in decreasing fasting blood glucose levels in type I diabetes model mice was reduced significantly (p = 0.023). (ii) Compared with sham-exposed insulin group, the percentage fluorescein isothiocyannate (FITC) labelling of HL-7702 cells was significantly reduced in the EMP-exposed insulin group (22.7-13.8%, respectively). (iii) Compared with sham-exposed insulin, the fluorescence intensity was significantly reduced in EMP-exposed insulin (p < 0.001). CONCLUSIONS: EMP exposure significantly decreased the bioactivity of insulin to reduce the blood glucose levels in type I diabetic mice. This could be due to a decreased binding affinity between insulin and its receptor. This mechanism could involve an alteration of insulin's' conformation caused by EMP exposure.