[Determination of 8-oxo-2'-deoxyguanosine and Cotinine in Urine by Hydrophilic Chromatography-tandem Mass Spectrometry with Isotope Dilution].

OBJECTIVE: To develop an assay for determination of 8-oxo-2'-deoxyguanosine and cotinine in human urine by hydrophilic chromatography tandem mass spectrometry (HILIC-MS/MS) with isotope dilution. METHODS: The urine supernatant was 1∶5 diluted with 3 mmol/L ammonium formate aqueous solution containing 15N 5-8-OHdG and D 3-cotinine as internal standard. After being filtered through a 0.22 µm water filter, the sample solution was injected into ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for analysis. Separation was performed on ACQUITY UPLC® BEH HILIC column (50 mm×3.0 mm, 1.7 µm) with isocratic elution (A∶B=10∶90) at 40 ℃. The mobile phase was composed with acetonitrile (B) and 3 mmol/L ammonium formate water soulution (A). The flow rate was 0.3 mL/min. Positive ion scan-multiple reaction monitoring (MRM) mode were used for monitoring and internal standard curves were applied for quantification. RESULTS: Good linearity was obtained under the optimal conditions. Detection limits for 8-OHdG and cotinine were 0.064 µg/L and 0.035 µg/L respectively, the quantitation limits were 0.21 µg/L and 0.12 µg/L respectively, and the recoveries of the spiked urine samples were 92.6%-102% and 102%-106% respectively. Statistical analysis of 40 urine sample determination results obtained by using the above assay showed that there were significant differences in tobacco smoke exposure and tobacco-specific nitrosamine intake between active and passive smoker ( P<0.05). The concentration of NNAL and cotinine were higher in urine samples of active smoker. Tobacco smoke exposure was positively correlated with tobacco specific nitrosamine intake in both active and passive smokers (the correlation coefficients were 0.487 and 0.786 respectively, P<0.05). CONCLUSION: We successfully established a simple and fast assay for simultaneously detecting 8-oxo-2'-deoxyguanosine and cotinine in human urine. It was sensitive and accurate for quntification via the calibration by the isotope internal standards, and can meet the needs of batch analysis.

[Detecting Nicotine and Cortinine in Hair by Hydrophilic Interaction Liquid Chromatography Tandem Mass Spectrometry].

OBJECTIVE: To develop a method for detecting nicotine and cotinine in hair by hydrophilic interaction chromatography tandem mass spectrometry. METHODS: Hair samples were hydrolyzed in sodium hydroxide solution before extraction with dichloromethane. The samples were blown to dry with nitrogen and dissolved with mobile phase. The filtrate of the samples was injected into a chromatographic-mass spectrometry system for analysis. The separation was performed by a hydrophilic column, with which methanol-0.1% ammonia was used as the mobile phase. The quantitative detection of Nicotine and Cortinine was carried out with electron spray ionization-triple quadrupole mass spectrometry. The established method was used for detecting nicotine and cotinine in 602 hair samples of pregnant women and 31 hair and urine samples of volunteers. RESULTS: A standard curve was drawn for the established method of hydrophilic liquid chromatography tandem mass spectrometry. Good linearity was obtained for detecting nicotine and cotinine in the range of 0.030-100.000 µg/L, with a detection limit (MDL) of 0.007 6 µg/g and 0.004 4 µg/g, respectively. The inter-day and intra-day precisions reached a level of less than 10%. The recoveries of the spiked samples ranged from 81.0% to 102.0%. About 0.020-0.260 µg/g nicotine and 0.004 8-0.069 0 µg/g cotinine were detected in the pregnant women without exposure to secondhand smoking (SHS), compared with 0.029-0.350 µg/g nicotine and 0.005 6-0.085 0 µg/g cotinine in those exposed to SHS. Nicotine and cotinine were also found in the hair and urine samples of volunteers, which were correlated with smoking (P < 0.05). A dose-response relationship were found between smoking and hair nicotine. CONCLUSIONS: The proposed method is accurate and sensitive for detecting nicotine and cotinine in hair samples. Hair nicotine can be a specific biomarker for assessing exposure to tobacco smoking.

[The application of functional magnetic resonance imaging integrated neuronavigation in localization and lingual function protection].

OBJECTIVE: To evaluate the clinical practicability of integration of functional magnetic resonance imaging (fMRI) data into neuronavigation as a tool to localize the language area and their relationship with the lesion for the preoperative planning, intraoperative guidance and postoperative follow-up study of brain functions during minimally invasive surgeries in or adjacent to functional areas. METHODS: Eighty eight patients with intracranial lesions located in or adjacent to the functional language area underwent fMRI (including examinations of lingual and visual function, and motor functions of the limbs and tongue). fMRI data was entered into a neuronavigation system for image fusion and preoperative registration and correction; minimally invasive neurosurgery was performed with fMRI navigation. RESULTS: The shortest distance between the lesion and the functional cortex was less than 5 mm in 6 patients and was more than 5 mm but less than 10 mm in another 10 patients, respectively. 10 patients were recovered and improved in another 6 between 3 - 6 months after surgery, The follow-up time was between 3 months and 1 year. The morbidity rate was 6.8% (6/88). There was no postoperative mortality. Various brain areas were widely activated when the patients were reading and understanding the Chinese words. The unilateral speech functional maps were located in left Brodmann's 9, 46, 17, 18 and 19 areas. CONCLUSION: fMRI-integrated neuronavigation can locate functional language areas and played an important role in intraoperative protection of functional lingual areas, execution of individualized therapeutic regimens, minimization of surgical complications and determination of prognosis. Total surgical resection was safe for lesions > 10 mm from functional lingual areas.

[Diagnosis and management of intracranial aneurysm in children].

OBJECTIVE: To describe the clinical manifestations of intracranial aneurysm in children and to evaluate the efficacy and safety of different therapeutic approaches for children with intracranial aneurysms. METHODS: Clinical data of 23 pediatric patients with intracranial aneurysms diagnosed and treated at our hospital over the past 18 years were retrospectively reviewed. Follow-up data were also collected and analyzed. RESULTS: Two patients received no further treatment. Surgery was performed in 16 patients. Among them, 15 achieved an excellent recovery and 1 died. 5 patients were treated with Guglielmi detachable coil (GDC). Aneurysm was successfully sealed off in one case and an excellent recovery achieved; remnant aneurysm was detected in two cases. One received trapping while another underwent aneurysmectomy. The patient died postoperatively. Another received neck clipping and resection. And the patient recovered well; two cases experienced aneurysm recanalization after interventional therapy. Among them, one received a second embolotherapy but it became recanalized again. And it was finally cured by aneurysmectomy. CONCLUSION: Aneurysm surgery is proved to be a safe and effective treatment for children with intracranial aneurysm. Endovascular treatment of intracranial aneurysms with GDC is also shown to be effective and safe for pediatric patient with acute SAH. But a long-term follow-up study is required to determine the clinical outcome. Once a aneurysm remnant or recanalization occurs, a microsurgical management is recommended.

[Effects of surgical microscope-based indocyanine green videoangiography during aneurysm surgery].

OBJECTIVE: To evaluate the effects of surgical microscope-based indocyanine green videoangiography (ICGA) in aneurysm surgery and compare the values of ICGA and postoperative digital subtraction angiography (DSA). METHODS: 101 patients with intracranial aneurysm underwent clipping of 113 aneurysms. A microscope-integrated light source containing infrared excitation light illuminated the operating field. The dye ICG was injected intravenously, and the intravascular fluorescence was recorded by a video camera attached to the microscope with optical filtering to block ambient and laser light for collection of only ICG-induced fluorescence. All patients underwent DSA 6-13 days post-operatively. The results of patency of parent, branching, and perforating arteries and documentation of aneurysm obliteration shown by ICGA and DSA were compared. RESULT: 219 times of ICGA was performed in these 101 patients with excellent image quality and resolution, allowing intra-operative real-time assessment of the cerebral circulation. The ICG angiographic results could be divided into arterial, capillary, and venous phases, comparable to those observed with DSA. In all cases, the postoperative angiographic results corresponded to the intraoperative ICG video angiographic findings. In 3 cases, the information provided by intraoperative ICGA significantly changed the surgical procedure. CONCLUSION: Simple and repeatable, microscope-based ICGA provides real-time information about vessels and aneurysm sac. This technique may be useful during routine aneurysm surgery as an adjunct to intraoperative microvascular Doppler ultrasonography and DSA.

[Advances in the expression and regulation of MnSOD gene].

MnSOD, which is an important oxygen free radical scavenger in organisms, has an effect to resist oxidative stress and tumor. The expression and regulation of MnSOD gene is a complicated process, which includes many kinds of transcription factors, cell signal molecules and cell signal pathways. It refers to three aspects including transcription regulation, post-transcription regulation and translation regulation. Transcription regulation is the primary step for MnSOD gene expression and plays a key role during the expression of MnSOD gene. The activity of transcription factors, which controls MnSOD gene expression, such as SP-1, AP-2, AP-1, NF-kB and so on, can be changed in the course of transcription regulation. Drugs and metalions can also affect those transcription factors' activity. Furthermore some genes mutation and depletion also have an influence on the activity of those transcription factors. Post-transcription regulation is in a way of changing the stability of mRNA and its translation. Translation regulation is a process to regulate edition, modification, binding to metalion and site-specific of MnSOD polypeptide. Recently a kind of manganese trafficking factor for mitochondrial MnSOD called MTMl which is very important for activation of MnSOD has been discovered. Here, we review the advances in this field with an emphasis on transcription regulation and translation regulation of MnSOD gene. And at last, we discussed the prospect of MnSOD gene expression and regulation.

Postoperative recovery from posterior communicating aneurysm complicated by oculomotor palsy.

BACKGROUND: Oculomotor palsy is a common complication in patients with posterior communicating aneurysm. This study was conducted to investigate the postoperative recovery of patients with posterior communicating aneurysm complicated with oculomotor palsy and to analyze the factors influencing length of recovery. METHODS: From 2000 to 2006, 148 patients with posterior communicating aneurysm were treated at our hospital, with 74 of them having concurrent unilateral oculomotor palsy. All of the patients underwent craniotomy after the diagnosis by means of whole-brain digital subtraction angiography (DSA). The patients were divided into two groups for observation of postoperative recovery during the follow-up period. Patients in group A were treated with simple pedicle clipping of the aneurysm while patients in group B were treated with pedicle clipping of the aneurysm and decompression of the oculomotor nerve. RESULTS: Of the 40 patients in group A, 20 underwent surgery within 14 days and completely recovered from oculomotor palsy in 10 - 40 days. Fourteen patients underwent surgery within 14 - 30 days, of whom 12 completely recovered within 30 - 90 days and 2 cases recovered incompletely. The remaining six patients underwent surgery after more than 30 days; of these, four patients recovered completely and two recovered incompletely. Of the 34 cases in group B, 15 underwent surgery within 14 days and completely recovered from oculomotor palsy in 10 - 40 days. Sixteen patients underwent surgery in 14 - 30 days, of whom 14 completely recovered in 30 - 90 days and 2 recovered incompletely. The remaining three patients underwent surgery after more than 30 days, of whom two patients recovered completely and one recovered incompletely. CONCLUSIONS: Early diagnosis and surgical treatment of patients with unilateral oculomotor palsy induced by posterior communicating aneurysm are important to full postoperative recovery of the oculomotor nerve. No correlation was found, however, between decompression of the oculomotor nerve, such as excision or puncture of the aneurysm, and postoperative recovery time.

[Functional magnetic resonance imaging-integrated neuronavigation and protection of brain function].

OBJECTIVE: To investigate the reliability and clinical value of functional magnetic resonance imaging (fMRI)-integrated neuronavigation in minimally invasive neurosurgery and protection of brain function. We demonstrate the correlation between the lesion-to-fMRI activation distance and occurrence of new postoperative deficit. METHODS: fMRI-integrated neuronavigation was used for minimally invasive neurosurgery in 20 patients with intracranial lesions located in or near eloquent brain areas. During standardized paradigms for hand, foot, and tongue movement, language and visual activation, echo-planar imaging T2 blood oxygen level dependent sequences were acquired by Siemens Medical Systems Trio 3.0 T and processed with SPM2. Neuronavigation was performed with Stealth station. RESULTS: fMRI data was integrated into neuronavigation successfully in all cases, functional neuronavigation with integration of fMRI allowed easy and precise identification of the eloquent brain areas and lesions except for 1 case for brain shift because of tumor stroke just before the operation. The localization of the tumor was corrected by intraoperative ultrasonography. Gross total resection was achieved in 18 patients, 2 patients had a subtotal resection. Neurological deterioration was seen in 4 patients, tumors all located in eloquent brain areas, 2 patients were recovered in 3 months the morbidity was 10.0%. The distance of a lesion to fMRI activation was more than 10 mm in 14 cases. The functional maps were located in left Brodmann's 9, 46, 17, 18 and 19 areas in 11 cases when the patients reading and understanding the Chinese words. CONCLUSIONS: Functional neuronavigation with integration of fMRI allows precise identification of the eloquent brain areas protects the brain function and decreases the morbidity especially for Chinese patients because of our special functional area of language. Our data suggest that the distance of a lesion to fMRI activation was more than 10 mm, complete resection can be achieved safely.

[Postoperative recovery of aneurysm of posterior communicating artery-induced oculomotor palsy: clinical observation of 52 cases].

OBJECTIVE: To explore the prognosis of aneurysm of posterior communicating artery-induced oculomotor palsy after surgery. METHODS: Fifty-two patients with aneurysm of posterior communicating artery-induced oculomotor palsy, 12 males and 40 females, aged 57, diagnosed by CT, MRI, and digital subtraction angiography, were divided into 2 groups: group A (n = 20, receiving simple clipping of the aneurysmal neck) and group B (n = 32, undergoing clipping of the aneurysmal neck followed by nerve decompression such as resection or puncture of the aneurysmal sac), and were followed up for 12 months (2-48 months). RESULTS: In the group A 10 patients were operated on within 14 days after the onset of oculomotor palsy showed complete recovery of the oculomotor nerve function within 40 days after operation; 8 patients were operated on within 14-30 days after the onset of oculomotor palsy showed complete recovery within 30-90 days after operation in 7 patients and incomplete recovery in 1 patient; and 2 patients were operated on 30 days after the onset of oculomotor palsy showed complete recovery within 6 months after operation in 1 patient and incomplete recovery in the other patient. In the group B 15 patients were operated on within 14 days after the onset of oculomotor palsy all showed complete recovery within 40 days after operation; 14 patients were operated on within 14-30 days after the onset of oculomotor palsy showed complete recovery within 30-90 days after operation in 12 patients and incomplete recovery in 2 patients; and 3 patients were operated on 30 days after the onset of oculomotor palsy showed complete recovery within 6 months after operation in 2 patients and incomplete recovery in the other one patient. There was no significant difference in the recovery rate between these 2 groups. Recovery of the oculomotor nerve function was remarkably correlated with the time of operation after the onset. CONCLUSION: Early diagnosis and treatment help recover the oculomotor nerve function. The recovery of the oculomotor nerve function is not related to the operation protocols.