ObjectiveTo investigate the role of intraoperative ultrasound (IOUS) in the surgical treatment of cerebral gliomas.MethodsThirty patients with primary supratentorial gliomas underwent microsurgery guided by intraoperative real-time ultrasound, IOUS was utilized for localization and delineation of the tumor as well as determination of the extent of resection.ResultsAll of 30 lesions were accurately defined by IOUS due to the distinct echogenicity compared with the normal brain. Solid low grade gliomas tended to be well circumscribed with regular sulcus, while central necrosis was most commonly present with malignant gliomas. Complete tumor extirpation was achieved by IOUS guidance in this group. Two patients exhibited mild neurological deficit following the surgery.ConclusionIOUS may provide valuable real-time information and facilitate effectual surgery with accuracy for the cerebral gliomas.

Racemases have been applied for the synthesis of enantiomerically pure compounds through the deracemization methods. Mandelate racemase from Pseudomonas putida was the only enzyme that catalyzes the interconversion of mandelate enantiomers. Using genome mining approaches, we identified 9 mandelate racemases (MRs). A novel racemase named ArMR with higher activity and better soluble protein expression, was isolated from Agrobacterium radiobacter. ArMR displayed the optimum catalytic activity at 50 ℃, pH 7.8 in Tris-HCl buffer. The half-life of ArMR at 50, 40 and 30 ℃ was 0.17, 27.2 and 70.7 h, respectively. KM parameter of ArMR towards (R)- and (S)-mandelic acid was 1.44 and 0.81 mmol/L, respectively; the corresponding kcat value was 410 s⁻¹ and 218 s⁻¹. In addition, KM of ArMR towards (R)- and (S)-2-chloro mandelic acid was 6.48 and 6.37 mmol/L, and the corresponding kcat value 0.22 s⁻¹ and 0.23 s⁻¹, respectively. Meanwhile, Mg²⁺ and Mn²⁺ could activate the enzyme whereas Zn²⁺ inactivated the enzyme completely. Discovery of more novel MRs provides supports further research and development of these racemases.