Shape- and Size-Dependent Refractive Index Sensing and SERS Performance of Gold Nanoplates.

Plasmonic sensors are promising for ultrasensitive chemical and biological analysis. Gold nanoplates (Au NPLs) show unique geometrical structures with high ratios of surface to bulk atoms, which display fascinating plasmonic properties but require optimization. This study presented a systematic investigation of the influence of different parameters (shape, aspect ratio, and resonance mode) on localized surface plasmon resonance properties, refractive index (RI, n) sensitivities, and surface-enhanced Raman scattering (SERS) enhancement ability of different types of Au NPLs through finite-difference time-domain (FDTD) simulations. As a proof of concept, triangular, circular, and hexagonal Au NPLs with varying aspect ratios were fabricated via a three-step seed-mediated growth method by the experiment. Both FDTD-simulated and measured experimental results confirm that the RI sensitivities increase with the aspect ratio. Furthermore, choosing a lower order resonance mode of Au NPLs benefits higher RI sensitivities. The SERS enhancement abilities of Au NPLs also predicted to be highly dependent on the shape and aspect ratio. The triangular Au NPLs showed the highest SERS enhancement ability, while it drastically decreased for circular Au NPLs after the rounding process. The SERS enhancement ability gradually became more intense as the hexagonal Au NPLs overgrown on circular Au NPLs with increasing volumes of HAuCl4 solution. The results are expected to help develop effective biosensors.

Tetratrichomonas in pyopneumothorax.

Pleural trichomonosis is clinically rare, and very few cases of trichomonal empyema have been reported so far. A rare case of an 81-year-old woman with pyopeumothorax presenting with recurrent fever and macroscopic pyuria was present. Microscopic examination of the pleural effusion showed mobile flagellated protozoa which molecular methods identified as Tetratrichomonas. In addition, Streptococcus anginosus was discovered in pleural fluid cultures. Treatment with imipenem/cilastatin and metronidazole successfully eliminated the pathogens and led to relief of clinical symptoms. In the context of a review of the relevant literature, the clinical application of molecular methods in the diagnosis of pleural trichomonosis is underlined.

[Surgical treatment and effect observation of cervical intraspinal benign neoplasms].

OBJECTIVE: To investigate the diagnosis, surgical procedure and clinical outcome of cervical intraspinal benign neoplasm. METHODS: Twenty-two cases confirmed pathologically were reviewed included 16 males and 6 females with an average age of 43.8 years old ranging from 18 to 56 years. Symptoms mainly included neck pain, numbness and weakness of the extremities, urinary and fecal incontinence, pyramid signs, etc. All underwent X-ray, CT and MRI, 11 cases were diagnosed as neurilemomas, 4 neurofibromas, 3 spinal meningiomas, 2 intraspinal cysts and 2 lipomas. The tumors were removed completely in 18 cases, above 60% in 3 cases and 25% with biopsy in 1 case. Cervical stability in 11 cases was restored after removal of tumors. RESULTS: All were followed-up for from 6 to 84 months(means 12.5 months). Symptoms improved in 20 cases and stable in 1 case and worsened in 1 case postoperatively according to JOA scoring system. Two patients recurred and were treated with second surgery. JOA scoring was (6.52 +/- 1.10) before operation, (11.42 +/- 0.79) after operation, there was statically significance (t = 21.38, P < 0.001). The average recover ratio of total was (46.7 +/- 2.46)%, cervical stability was (62.37 +/- 3.58)%, the other methods was (41.21 +/- 4.63)%. The results of JOA were excellent in 18 cases, good in 2, fair in 1 and poor in 1. CONCLUSION: The surgical exairesis for cervical intraspinal benign neoplasm has low post-operative recurrence. The main reason of recurrence is not removed the tumor completely. MRI is regarded the effective method which is helpful in differential diagnosis and surgery guidance.