Apoptotic Effect of 1800 MHz Electromagnetic Radiation on NIH/3T3 Cells.

To investigate the effect of 1800 MHz electromagnetic radiation (EMR) on apoptosis, we exposed NIH/3T3 cells at 1800 MHz with a specific absorption rate (SAR) of 2 W/kg intermittently for 12, 24, 36, and 48 h. After exposure, Cell Counting Kit-8 (CCK-8) and flow cytometry were used to detect cell viability and apoptosis; the expression of p53, a molecule with the key role in apoptosis, was measured by real-time qPCR, western blot, and immunofluorescence; and images of the structure of the mitochondria, directly reflecting apoptosis, were captured by electron microscopy. The results showed that the viability of cells in the 12, 36, and 48 h exposure groups significantly decreased compared with the sham groups; after 48 h of exposure, the percentage of late apoptotic cells in the exposure group was significantly higher. Real-time qPCR results showed that p53 mRNA in the 48 h exposure group was 1.4-fold of that in the sham group; significant differences of p53 protein fluorescence expression were observed between the exposure groups and the sham groups after 24 h and 48 h. The mitochondrial swelling and vesicular morphology were found in the electron microscopy images after 48 h exposure. These findings demonstrated 1800 MHz, SAR 2 W/kg EMR for 48 h may cause apoptosis in NIH/3T3 cells and that this apoptosis might be attributed to mitochondrial damage and upregulation of p53 expression.

Recombinant DENV 2 NS5: An effective antigen for diagnosis of DENV infection.

Dengue fever is a mosquito-borne viral disease with dramatically increasing morbidity rate worldwide in decades. Since there is no specific treatment to date, early diagnosis is important for providing proper timely medical care to minimize mortality, and for the prompt initiation of public health control measures. NS5 is a potential biomarker for dengue virus infection due to its highly conserved and immunogenic properties. In this study, the DENV 2 NS5 full-length and the DENV 2 NS5 C-terminus RNA-dependent RNA polymerase domain fragment (NS5-C70) expression plasmids were constructed, and the 104 kDa full-length NS5 and the 70 kDa NS5-C70 were respectively expressed in Escherichia coli. These two purified recombinant products were found to react with the sera of patients infected with dengue virus when analyzed by an enzyme-linked immunosorbent assay (ELISA), which resulted in significantly higher absorption values than those of control sera. The recombinant DENV 2 NS5 exhibited strong reactivity to each of the four types of sera, whereas the NS5-C70 showed strong reactivity only to DENV 2 and 4. In comparison, the positive agreement value of recombinant NS5-based assay with either MyBioSource or Panbio assay was higher than that of the two commercially available IgG indirect ELISA kits. These results suggest that the recombinant DENV 2 NS5 be an effective antigen for detection of dengue virus infection. The recombinant NS5-C70 may also be used as an auxiliary antigen for diagnostic purposes.

Protective effect of hydrogen-rich saline on ischemia/reperfusion injury in rat skin flap.

OBJECTIVE: Skin damage induced by ischemia/reperfusion (I/R) is a multifactorial process that often occurs in plastic surgery. The mechanisms of I/R injury include hypoxia, inflammation, and oxidative damage. Hydrogen gas has been reported to alleviate cerebral I/R injury by acting as a free radical scavenger. Here, we assessed the protective effect of hydrogen-rich saline (HRS) on skin flap I/R injury. METHODS: Abdominal skin flaps of rats were elevated and ischemia was induced for 3 h; subsequently, HRS or physiological saline was administered intraperitoneally 10 min before reperfusion. On postoperative Day 5, flap survival, blood perfusion, the accumulation of reactive oxygen species (ROS), and levels of cytokines were evaluated. Histological examinations were performed to assess inflammatory cell infiltration. RESULTS: Skin flap survival and blood flow perfusion were improved by HRS relative to the controls. The production of malondialdehyde (MDA), an indicator of lipid peroxidation, was markedly reduced. A multiplex cytokine assay revealed that HRS reduced the elevation in the levels of inflammatory cytokines, chemokines and growth factors, with the exception of RANTES (regulated on activation, normal T-cell expressed and secreted) growth factor. HRS treatment also reduced inflammatory cell infiltration induced by I/R injury. CONCLUSIONS: Our findings suggest that HRS mitigates I/R injury by decreasing inflammation and, therefore, has the potential for application as a therapy for improving skin flap survival.

[Detection of SARS-CoV and RNA on aerosol samples from SARS-patients admitted to hospital].

OBJECTIVE: To assess the risk of aerosol transmission in severe acute respiratory syndrome (SARS) patients admitted to Hospital through testing the air samples. METHODS: Air samples were collected from 7 wards and 1 balcony of the Hospital, 3 times a day for 3 continuous days, using bioaerosol sampler type FA-2. Bioaerosol particles were then washed down from the samples by serum-free Dulbecco's Modified Eagle Medium (DMEM) culture medium. Nested-reverse transcription-polymerase chain reaction (RT-PCR) was used to amplify the N protein gene of the SARS associated coronavirus (SARS-CoV) from these washing solutions. The residual solutions were inoculated into prepared cell cultures to isolate live virus. The positive samples were then identified by indirect immunofluorescence assay and sequence analysis of the PCR products. RESULTS: Positive rates of RT-PCR test on air samples were 29.03% in the wards and 20.0% in balcony respectively. Results from sequential analysis showed that the homology of amplified cDNA fragments to previously known SARS-CoV stains was 98%. A strain of live pathogen was isolated from one of the 36 samples. The isolate could cause typical cytopathic effects, similar to those SARS-CoV on Vero-E6 cells and the effects could be stably passed. Indirect immunofluorescence assay showed positive from serum of a SARS patient. CONCLUSION: SARS-CoV existed in the air hospital, where SARS patients were admitted to, but the activity of SARS-CoV in air samples was rather low. SARS patients could still shed SARS-CoV even during the recovery phase. Potential possibility of aerosol transmission might exist within 1 meter square area around SARS patients.