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Structured light have made deep impacts on modern biotechnology and clinical practice, with numerous optical systems and lasers currently being used in medicine to treat disease. We demonstrate a new concept of fiber‐based optical hook scalpel. The subwavelength photonic hook is obtained in the vicinity of a shaped fiber tip with asymmetric radiation. A 1550 nm continuous‐wave source, commonly used for medical imaging, has been required. Photonic hook with a lateral feature size less than the half‐wavelength is achieved using a hemispherical shaped fiber tip with metallic mask. This breakthrough is carried out in ambient air by using a 4‐μm‐diameter fiber with a shaped tip. A good correlation is observed between the computed intensity distribution of photonic hook and the tip sizes. Photonic hook generated with a shaped fiber tip, easier to manipulate, shows far‐reaching benefits for potential applications such as ophthalmic laser surgery, super‐resolution microscopy, photolithography and material processing. [ABSTRACT FROM AUTHOR]

The article presents a study on H5 and H7 subtype influenza virus DNA vaccine's experimental and construction immunity.

Trapping and manipulating mesoscopic biological cells with high precision and flexibility are very important for numerous biomedical applications. In particular, a photonic nanojet based on a non-resonance focusing phenomenon can serve as a powerful tool for manipulating red blood cells and tumor cells in blood. In this study, we demonstrate an approach to trap and drive cells using a high-quality photonic nanojet which is produced by a specific microcone-shaped optical-fiber tip. The dynamic chemical etching method is used to fabricate optical-fiber probes with a microcone-shaped tip. Optical forces and potentials exerted on a red blood cell by a microcone-shaped fiber tips are analyzed based on finite-difference time-domain calculations. Optical trapping and driving experiments are done using breast cancer cells and red blood cells. Furthermore, a cell chain is formed by adjusting the magnitude of the optical force. The real-time backscattering intensities of multiple cells are detected, and highly sensitive trapping is achieved. This microcone-shaped optical fiber probe is potentially a powerful device for dynamic cell assembly, optical sorting, and the precise diagnosis of vascular diseases.

The residential regions of Yunnan province, canton of Jing Hong, in China were surveyed for Japanese encephalitis virus (JEV) infection in mosquito and swine vectors to determine the frequency of JEV-carrying zoonotic vectors in 2009-2010. A total of 21,500 mosquitoes were collected and divided by species, and brain tissue was collected from 108 stillborn piglets. The infection rates for the different JEV species were 13.2% for Culex tritaeniorhynchus, 2.7% for Anopheles sinensis, 0.7% for Armigeres subalbatus, and 18.5% for stillborn piglets. The complete genomes of two JEV samples that were collected in different seasons and different regions, Yunnan 0901 and Yunnan 0902, were sequenced from a pool of Culex mosquitoes and stillborn piglets that had been collected randomly from several piggeries. Multiple sequence alignment with 24 fully-sequenced genes and 93 complete sequences of the JEV-encoded E gene revealed nucleotide homologies ranging from 97.2-99.6% and 94.5-99.7% in mosquitoes and piglets, respectively, and deduced amino acid homologies ranging from 97.4-98.1% and 96.0-98.2%, respectively. Phylogenetic analyses of the Yunnan 0901 and Yunnan 0902 strains' full-length genomes and E gene sequences indicated that these strains are most closely related to six Chinese SA14-derived viruses, and distantly related to the Australian FU, vellore P20778, and Japanese Ishikawa strains, and the previously isolated YN86-B8639 strains. The phylogenetic relationships based on the full-length genome were similar to those found for the E gene, indicating that phylogenetic analysis of the E gene will be a useful approach for genotyping of JEV, but not to better understand the potential changes in the biological characteristics and genetic relationship of JEV isolates.

Japanese encephalitis (JE) can infect many agriculturally important animals and humans, and has a high incidence in Asia. One of the natural hosts of the mosquito-borne JE virus (JEV) is domestic pigs, which act as amplifier hosts. Porcine infection results in fatal encephalitis, abortion, and stillbirth in pregnant sows, and hypospermia in boars. In this study, a rapid JEV detection method for swine and mosquitoes was developed based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) targeting the nucleocapsid (E) genes of JEV genotype I (lineage K94PO5), and genotype III (lineage SA14-14-2). Fifty-six swine blood samples and 20,000 mosquitoes were used to evaluate the method, compared to conventional RT-polymerase chain reaction (PCR) and real-time RT-PCR. RT-LAMP had detection limits of 2.57 and 2.34 copies/μL for JEV I and III, respectively. Assay sensitivity was similar to real-time RT-PCR, but was 10-fold higher than conventional RT-PCR. Assay specificity was high, showing no cross-reactivity to other flaviviruses. The results of virus isolation and identification of swine blood samples and mosquito samples were fully consistent with RT-LAMP. Finally, the JEV RT-LAMP assay was simpler and less time consuming than conventional RT-PCR or real-time RT-PCR, since the amplification step could be completed in a single tube within 50 min at 63°C. In conclusion, the newly-developed RT-LAMP assay is an accurate and convenient method for rapid and sensitive diagnosis of JEV in swine and mosquitoes, and may prove to be a practical molecular tool for surveillance and epidemiological investigations.

Objective: To investigate characteristics of circadian rhythm in intracerebral hemorrhage before death., Methods: This retrospective study was carried out from September 2002 to February 2009. One hundred and twenty-two dead cases with intracerebral hemorrhage(ICH) were collected. The study was carried out in the Department of Neurosurgery in The Second Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China. Blood pressure (BP) and heart rate (HR) were recorded every half-hour during the 72 hours before death. Data of BP and HR before deaths were divided into 3 time periods, namely, period A (72-48 hours to death), period B (48-24 hours to death), and period C (24 hours to death). Data from the 3 periods were analyzed using the Cosinor method to determine whether circadian rhythm was present or absent. The cases were divided into a present and absent group after Cosinor analysis. Prognostic factors in the 2 groups were analyzed by Student`s t-test and Pearson`s chi-squared test., Results: Significant differences in prognostic factors between the 2 groups were not found. When circadian midline-estimating statistic of rhythms over the 3 periods were compared, there were no significant differences. However, when circadian amplitudes over the 3 periods were compared, the amplitudes during period C were significantly lower than period A or B (p<0.001). The percentage of cases in the absent and present groups was significantly different (p<0.001) over the 3 periods., Conclusion: As an independent factor, circadian variation could predict death in patients with ICH.

Objective: To study the influence of different surgery on heart rate's circadian rhythm in postoperation of intracerebral hemorrhage., Methods: One hundren cases of hypertensive intracerebral hemorrhage at basal ganglia had been collected. According to methods of operation, cases were divided into two groups. Forty-three cases and 57 cases were treated respectively by standard craniotomy (Craniotomy group) and microinvasion of puncturation (Microinvasion group) to remove hematoma. Value of heart rate (HR) was recorded by monitor every 1 hour for 9 days. Circadian rhythm of every day was analyzed by single cosinor and population mean-cosinor., Results: Circadian rhythm of postoperative HR appeared (P < 0.001) in microinvasion group after operation. Circadian rhythm of postoperative HR had not been appearing (P < 0.001) in craniotomy group until to the 8th day. All amplitudes in microinvasion group are higher than that in craniotomy group. Both of amplitudes in two groups begin to be low during 4-7 d after operation and recover the level till the 8th day., Conclusion: Influence of circadian rhythm in craniotomy was more severe than microinvasion puncturation. There would be a intimate relationship between encephaledema and recovery of circadian rhythm after neurosurgery.