[Operative strategy and clinical results of complex four part distal radius fractures by combined palmar and dorsal internal fixation].

Objective: To explore a standard procedure for the treatment of combined dorsal and palmar internal fixation for complex four part distal radius fractures and assess its clinical results. Methods: From May 2009 to October 2016, 38 patients(39 sides)who suffered from complex four part distal radius fractures were performed operatively with open reduction and internal fixation via combined dorsal and palmar approach in Department of Orthopaedic Trauma, Qilu Hospital of Shandong University(Qingdao). The series included 22 males(22 sides) and 16 females(17 sides). Age of the patients was 53.5 years ranging from 25 to 79 years.According to Melone classification, there were 34 sides of type of Ⅳ, 5 of type Ⅴ.According to Frykman classification, there were 15 sides of type Ⅶ, 24 sides of type Ⅷ, and all the cases were type C3 according to AO/OTA classification.Preoperatively, the key articular fragments in four part distal radius fractures were identified and the individual fracture patterns from conventional X-ray and CT-scan were analyzed. All the patients were performed combined volar and dorsal fixation.Firstly, a palmar approach which gave access to and fix the palmar-ulnar fragment and the radial styloid fragment was performed.Then a limited dorsal approach across the third extensor compartment which gave access to the dorso-ulnar fragment and a limited dorsal arthrotomy to visualize the radiocarpal joint when necessary were performed.Through dorsal approach, we can address the dorso-ulnar fragment, free intra-articular fragment and direct visualize the joint.Use of a retinacular flap was routinely advocated to help prevent against tendon irritation and rupture.The follow-up control included conventional X-ray, range of motion(ROM), grip strength, and the disabilities of the arm, shoulder and hand index(DASH), as well as the patient-rated wrist evaluation(PRWE) score for functional outcome at 6 and 12 months. Results: Thirty-three patients(34 sides) were followed up for at least 12 months.The would healed well in all cases 2 weeks postoperatively, and no soft tissue infections, necrosis or neurovascular complications occurred.All the fractures of 38 cases(39 sides)healed averaged 3.6 months(ranging from 2.5-5.7 months), and no loss of reduction occurred postoperatively.Anatomic reconstruction with a step or gap of <1 mm was achieved in 37 cases(38 sides), Whereas 5 patients were lost to follow-up at 12 months postoperatively.ROM and grip strength were all recovered to over 85% of the unaffected side(exception of the bilateral patient). Median DASH-index and PRWE were 6.5(0-17) and 9.3(0-20)respectively. Conclusion: Combined volar and dorsal approaches allow achieving anatomic reconstruction in complex four part intra-articular distal radius fractures and reveal good functional outcomes at intermediate follow-up.

Highly efficient and compact cavity oscillator for high-power, optically pumped gas terahertz laser.

We demonstrate a highly efficient and compact terahertz cavity oscillator that is based on z-cut crystal quartz used as the dichroic beam splitter, for the first time to the best of our knowledge. With D(2)O gas as the active medium, pumped with a multitransverse mode TEACO(2) laser, experimental verification was also presented to demonstrate the advantages of this cavity oscillator. With the cavity length of 120 cm, 7.4 mJ pulse energy at pulse repetition frequency of 6 Hz, pulse width of 90 ns, and peak power of 82.2 kW were achieved at a wavelength of 385 µm. Photon conversion efficiency (PCE) of 44% was obtained at the maximum output level from this terahertz cavity oscillator. Furthermore, to our knowledge, this PCE is the highest efficiency ever reported in D(2)O gas, 385 µm terahertz cavity laser systems. The beam quality or M(2) factor was found to be about 1.77.

Expression and bioactivity analysis of recombinant beta-CPP dimer.

Beta-casein phosphopeptide (beta-CPP) is a bioactive peptide that carries different minerals, especially calcium. To investigate more effects of beta-CPP, eukaryotic expression vector of beta-CPP dimer was constructed and transfected into Chinese hamster ovary (CHO) cells. After selection, the cell lines stably expressing beta-CPP dimer were obtained, and the recombinant product was identified and purified. Activity assay of recombinant protein indicated that the recombinant beta-CPP dimer could improve Ca(2+) uptake of sperm, stimulate the proliferation of spleen cells, and induce apoptosis of some malignant tumor cells.