ABSTRACT
L-homophenylalanine (L-HPA) is an important non-natural amino acid that has been used as a key intermediate for the synthesis of Puli drugs for the treatment of hypertension. At present, L-HPA is synthesized using chemical methods, which has the disadvantages of expensive raw materials, tedious steps and serious pollution. Therefore, researchers have conducted in-depth research on the enzymatic production of L-HPA. This review summarizes the research progress on the enzymatic synthesis of L-HPA, including the dehydrogenase process, the transaminase process, the hydantoinase process, and the decarboxylase process, with the hope to facilitate the industrial production of L-HPA.
Subject(s)
Amino Acids , Environmental Pollution , Industry , Protein BiosynthesisABSTRACT
Objective Introduce a technique for creating 3-dimensional (3D) brain models of subdural electrodes , ideal for demonstrating the space-relationship of seizure localization and eloquent cortices , and discuss its usefulness for presurgical evaluation of epileptic patients. Methods Patients with medically intractable epilepsy were underwent a thorough preoperative MR brain scan including a T1-weighted high-resolution 3D sequence. Intraoperative photographs were taken with the digital camera. After the surgical implantation of subdural electrodes for epileptic zone localization , the thin-slice CT scan of the electrodes were taken and coregistered to preoperative brain 3D MR images in the Medtronic StealthMerge software environment. After the iEEG monitoring , multiple habitual seizures were recorded , eloquent areas were also identified by electrical stimulation of the cortex. The epileptic zone and the eloquent areas were marked on the subdural electrodes respectively. Then, 3D tessellations of the epileptic zone and the eloquent areas were rendered. Results Six patients (4 male, 2 female) were enrolled in this study. The mean time of iEEG monitoring was 13.7 days. After the coregistration of postoperative CT with preoperative 3D MRI , the 3D stereoscopic reconstruction provided an accurate representation of the implanted electrodes with highly detailed visualization of the underlying anatomy. The visual comparison between 3D reconstructions and intraoperative photographs indicated a good correspondence. The patients were followed for 3 to 6 months after the secondary operation , and had continuing improvement in seizure control. Conclusions The results indicate that the 3D reconstruction of subdural electrodes can reveal the precise localization of subdural electrodes , and can be useful for the presurgical evaluation of epileptic patients.
ABSTRACT
Objective To assess the clinical effect of lumboperitoneal shunting (LPS) on communicating hydrocephalus.Methods An retrospectively study was conducted on communicating hydrocephalus patients who were hospitalized from Sep.2009 and Dec.2013 at the No.174th Hospital of Chinese People's Liberation Army.All patients were underwent the LPS.All patients were with difference degrees of coma,and lumbar punctured for continued cerebrospinal fluid extended drainage before LPS.The change of disturbance of consciousness and the complications of LPS were assessed.Results There were 12 patients with communicating hydrocephalus.Of them,7 cases were underwent routine lumboperitoneal shunts,and 5 cases were experienced adjustment valve.After the LPS operation,3 patients were awakened from the coma,and 8 patients were improved in terms of consciousness and the decompression pressure of skull window as well as decreased enlarged lateral ventricles in pre-operation by CT.As for another 1 patient,the lumboperitoneal catheter had been slipped into the peritoneal cavity after 2 months of operation.There were no complications of infection,intracranial hemorrhages,obstruction of catheter and epilepsy.Conclusion The LPS should be the first selection of those patients who suffered from communicating hydrocephalus without trouble in spine and abdomen.A positive response to pre-operative continuing cerebrospinal fluid extend drainage is good prediction factor for surgical results of LPS.