The ascorbic acid in plasma was determined on the basis of reduction of ferric to ferrous ion and its formation of a colored complex with batho-phenanthroline. This method was highly correlated to Roe's dinitrophe-nylhydrazine method in the determination of plasma ascorbic acid of 16 normal adults and the correlation coefficient was 0.90. By animal experiment the new method may be used to discriminate different levels of plasma ascorbic acid. It is rather simple and water bath is not required. Only 0.25ml of plasma is needed for each determination. So this method is useful in assessing the ascorbic acid nutriture in tield survey.

Objective To investigate CT and MRI imaging of Warthin tumor of parotid gland.Methods CT and MRI character-istics of 5 1 patients confirmed as Warthin tumor by operation and pathology were analyzed retrospectively.Results Among 5 1 cases, 43 patients were males,and 8 patients were females.A total of 84 lesions were found in all cases,20 cases had at least 2 lesions.The margins of lesions were well-defined.68 lesions were round or elliptical.45 lesions located in the posterior and inferior quadrant of the parotid gland completely or premodinantly.The density and signal of most lesions were homogeneous.The parenchymal area of most lesions showed an early moderate-remarkable enhancement.Small blood vessels surrounded the lesions in 1 9 cases.Conclusion CT and MRI are important and valuable for the diagnosis of Warthin tumor.

Objective To discuss bilateral percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP) using inside and outside intravertebral vacuum cleft (IVC) respectively with bone cement injection for the treatment of Kümmell disease.Methods From January 2008 to October 2015,16 cases of Kümmell disease patients were treated with bilateral PVP or PKP with inside and outside IVC perfusion of bone cement respectively.Of 16 cases,6 were male and 10 were female,aged from 63 to 94 years,with a disease duration from 2 to 15 months.The bone mineral density of every patient was measured by dual-energy X-rayabsorptiometry.The T value ranged from-4.3 to-2.6.Fractures located from T10 to L4,including 2 cases of multiple fractures.Postoperative X-ray was used to observe the vertebral bone cement leakage and anterior height changes of affected vertebrae.Visual analogue scale (VAS) and Oswestry disability index (ODI) were used to evaluate pain status and functional activity.Results All cases were followed up for 12-96 months.Cement leakage occurred in 4 patients without nerve complications.The anterior height of affected vertebrae before operation,2 d after operation and at the last follow-up was (50.3 ± 8.3)％,(67.1 ± 8.1)％ and (65.2 ± 6.4)％.The anterior height of affected vertebrae 2 d after operation and at the last follow-up were significantly improved compared with those before operation (P ＜ 0.05),but there were no significant differences between 2 d after operation and at the last follow-up (P ＞ 0.05).The scores of VAS before operation,2 d after operation and at the last followup was (8.63-± 1.23),(2.56 ± 3.48) and (1.38 ± 0.92) scores,and the scores of ODI was (82.1 ± 6.7)％,(28.5 ± 7.3)％ and (22.1 ± 8.2)％.The scores of VAS and ODI 2 d after operation and at the last follow-up were significantly decreased compared with those before operation (P ＜ 0.05),but there were no significant difference between 2 d after operation and at the last follow-up (P ＞ 0.05).There was no postoperative in situ or adjacent vertebral fracture.Conclusions Using internal and external IVC bone cement injection for treatment of Kümmell disease has a good clinical curative effect.It can effectively relieve back pain symptoms,reduce intraoperative and postoperative bone cement leakage and recurrent adjacent or in situ vertebral fracture.

Objective To explore the neuroprotective effects ofβ-aescinate on brain edema in rats of traumatic brain injury (TBI). Methods A total of 78 male SD (Sprague Dawley) rats were randomly divided into three groups: sham-operation group (Sham), traumatic brain injury group (TBI) andβ-aescinate group, with 26 rats in each group. Rats of Sham group were anesthetized and surgically prepared only, but were not induced by cortical contusion. Electronic brain cortical damage impactor (eCCI) was used for establishing TBI model in TBI group and β-aescinate group after opening the bone window. TBI group was only established TBI model, but no intervention. After establishment of TBI model in β-aescinate group, β-aescinate (5 mg/kg body weight) was intraperitoneally injected, once every 24 hours. The modified neurological severity scores (mNSS) was used for evaluating changes of neurological function. After 48 hours, SD rats were sacrificed for hematoxylin and eosin (H&E) staining (n=6). Additionally, water content of the brain tissue was evaluated using the wet-to-dry weight ratio (n=10). Evans blue assay was performed to investigate the blood-brain barrier (BBB) permeability (n=4). The expression of aquaporin 4 (AQP4) was measured by Western blot assay (n=6). Results Compared with the Sham group, neurologic deficit, increased brain water content and the expression of AQP4 were found in TBI group (all P<0.05). Moreover, BBB permeability was destroyed. However, β-aescinate can improve the neurological function, reduce the brain water content and significantly decrease the expression of AQP4 in TBI rats. The BBB permeability was significantly improved in treatment group (all P<0.05). Conclusion These findings suggest that β-aescinate can reduce cerebral edema and improve neurological outcome in SD rats after TBI. This neuroprotection may be related with the down-regulation of AQP4 protein.

Objective:To investigate the stress distribution in peri-implant bone with All-on-4 implant with various parameters by three-dimensional finite element method.Methods:An edentulous mandibular specimen was scanned by CT Mimcs.Geomagic,Uni-graphics,HyperMesh modeling software were used to establish All-on-4 implant finite element models with different inclination angles and corresponding cantilever lengths.1 50 N vertical static load was applied at the right end of the cantilever,peri-implant bone stress was analysed using Abaqus software.Results:When the distal implant inclined 0°with cantilever length of 1 9.5 mm,the peak stress in peri-implant cortical bone at the mesial and distal side was 25.526 MPa and 83.026 MPa respectively.When the distal implant in-clined 1 5°,30°and 45°with the cantilever length of 1 7.2 mm,1 3.3 mm and 9.8 mm,the stress in perio-implant cortical bone at distal side of the implant reduced by 1 2.4%,35.6% and 53.1 %,that at mesial side of the implant reduced by 1 3.6%,36.3% and 40.2%,respectively.Conclusion:From the perspective of the stress analysis,the design of All-on-4 distal implant with large incli-nation angle and short cantilever is superior to that with small inclination angle and long cantilever.

Objective To investigate the relationship between mismatch repair (MMR) protein expression and microsatellite instability (MSI) and tumor TNM staging in colorectal cancer. Methods The clinical data of 1351 patients who underwent radical resection of colorectal cancer at the Xijing Digestive Hospital of Air Force Military Medical University from January 2008 to December 2017 were retrospectively analyzed. The MMR and MSI status in patients with different gender, age and TNM staging were analyzed. Results Of the 1351 specimens, 291 (22％) didn't express MMR protein. Univariate analysis showed that there were significant differences in the deletion rates of MSH2, MSH6 and PMS2 between patients ≥60 years old and<60 years old (all P<0.05);there were significant differences in the deletion rates of MSH2 between stage T3 and the other stages (P<0.05); the deletion rates of MLH1, PMS2 among different N stages, and the deletion rates of MSH2 and MSH6 between stage N0 or N1 and the other N stages were significantly different (all P< 0.05); the deletion rates of PMS2 among different M stages were significantly different (P< 0.05). There were significant differences in PMS2 deletion rates among different TNM stages and MLH1, MSH2 and MSH6 deletion rates between stage Ⅱ or Ⅲ and the other stages (all P< 0.05). There was significant difference in MSI positive rates between patients ≥60 years old and<60 years old (P<0.05); there were significant differences in MSI positive rates between stage T3 or T4 and the other T stages, among different N or M stages, and between TNM stage Ⅱ, ⅢorⅣand the other TNM stages (all P<0.05). Conclusions The MMR protein expression and MSI in colorectal cancer patients are closely related to tumor TNM staging. Detection of MMR protein expression and MSI in colorectal cancer patients has certain reference value for judging TNM staging of colorectal cancer. To a certain extent, it can guide the diagnosis and treatment of patients with colorectal cancer and judge the prognosis.

Objective:To investigate the risk factors of lymph node metastasis for patients with colorectal cancer in T 3 and T 4, and to provide a reference for clinical diagnosis and treatment. Methods:The clinicopathological data of 1 112 patients with colorectal cancer in T 3 and T 4 who underwent radical resection of colorectal cancer in Xijing Digestive Disease Hospital from January 2008 to December 2017 were retrospectively analyzed. The correlation between lymph node metastasis status and the clinicopathological factors as well as tumor markers was analyzed. The related risk factors of lymph node metastasis were analyzed by using logistic multivariate regression analysis. Results:Univariate analysis showed that there was no statistically significant difference in the incidence of lymph node metastasis among colorectal cancer patients stratified by gender, age and tumor location (all P > 0.05). The different tumor diameter [<5 cm and ≥5 cm: 37.75% (211/559), 52.26% (289/553), χ2 = 23.666, P < 0.01], general type [infiltration, ulcer, parasol, bulge: 37.04% (20/54), 47.52% (432/909), 34.33% (23/67), 69.51% (57/82), χ2 = 13.787, P = 0.003], degree of differentiation [highly-differentiated, moderately-differentiated, poorly-differentiated: 34.11% (102/299), 49.00% (317/647), 48.80% (81/166), χ2 = 19.771, P < 0.01], mismatch repair deficiency (dMMR) [yes and no: 26.34% (64/243), 50.17% (436/869), χ2 = 43.996, P < 0.01], neurological invasion [yes and no: 48.17% (421/874), 33.20% (79/238), χ2 = 16.954, P < 0.01], vascular invasion [yes and no: 79.16% (338/427), 23.65% (162/685), χ2 = 327.493, P < 0.01] and preoperative carcino-embryonic antigen (CEA) [positive (≥5 mg/ml) and negative (<5 mg/ml): 52.87% (249/471), 39.16% (251/641), χ2 = 20.162, P < 0.01] and CA199 [positive (≥35 U/ml) and negative (<35 U/ml): 59.33% (124/209), 41.64% (376/903), χ2 = 21.465, P < 0.01] had statistically significant differences in the incidence of lymph node metastasis for above stratified patients. Logistic multivariate regression analysis showed that vascular invasion and preoperative CA199-positive were independent risk factors for lymph node metastasis in patients with colorectal cancer in T 3 and T 4 ( OR = 13.006, 95% CI 9.329-17.276, P < 0.01; OR = 2.194, 95% CI 1.513-3.181, P < 0.01), and dMMR-positive was a protective factor for lymph node metastasis ( OR = 0.279, 95% CI 0.190-0.411, P < 0.01). Conclusions:Vascular invasion is the main risk affecting factor for the lymph node metastasis of patients with colorectal cancer in T 3 and T 4. The detection of preoperative tumor marker CA199 can be used as an index to predict the lymph node metastasis of patients with colorectal cancer in T 3 and T 4. To a certain extent, it can provide a reference for the diagnosis and treatment of patients with colorectal cancer in T 3 and T 4.

Objective To evaluate the relationship betweenα2 adrenergic receptors and expression of Nav1. 8 in dorsal root ganglion (DRG) neurons, and to illuminate the mechanism of dexmedetomidine-induced reduction of acute visceral pain in rats. Methods Thirty-two clean-grade healthy adult male Spra-gue-Dawley rats, aged 6-8 weeks, weighing 180-220 g, were divided into 4 groups ( n=8 each) using a random number table method: control group ( group C ) , acute visceral pain group ( group VP ) , dexmedetomidine group (group D), and dexmedetomidine plus atipamezole group (group DA). In VP, D and DA groups, 10-3 mmol∕L capsaicin 1. 3 ml was injected into the rectum at a dose of 10-3 mmol∕L to establish the acute visceral pain model, while the equal volume of normal saline was given instead in group C. Atipamezole 1 mg∕kg was subcutaneously injected through the back of the neck at 20 min before establishing the model in group DA. Dexmedetomidine 10μg∕kg was injected through the tail vein at 15 min before establishing the model in D and DA groups, while the equal volume of normal saline was given instead at the correspording time points in C and VP groups. The visceral pain behavior score was recorded at 1 h after establishing the model. The animals were then sacrificed, and DRGs of the lumbar segment (L3-6) were removed for determination of the number of Nav1. 8 positive DRG neurons (by immunohisto-chemistry) and expression of Nav1. 8 mRNA (by quantitative real-time polymerase chain reaction). Results Compared with group C, the visceral behavior scores and the number of Nav 1. 8 positive DRG neurons were significantly increased, and the expression of Nav 1. 8 mRNA was up-regulated in VP, D and DA groups (P<0. 05). Compared with group VP, the visceral behavior score and the number of Nav1. 8 positive DRG neurons were significantly decreased, and the expression of Nav 1. 8 mRNA was down-regulated in D and DA groups (P<0. 05). Compared with group D, the visceral behavior scores and the number of Nav1. 8 positive DRG neurons were significantly increased, and the expression of Nav1. 8 mRNA was up-regulated in group DA ( P<0. 05) . Conclusion The mechanism by which dexmedetomidine reduces acute visceral pain is related to activatingα2 adrenergic receptors and to down-regulating the expression of Nav1. 8 in DRG neu-rons of rats.

Objective To investigate the effect of dexmedetomidine pretreatment on inflammatory visceral pain in rats. Methods Forty healthy male Wistar rats, weighing 200-300 g, aged 6-8 weeks, were divided into 5 groups ( n=8 each) using a random number table method: control group ( group C) , visceral pain group ( group VP ) , dexmedetomidine 1 μg∕kg group ( group Dex1 ) , dexmedetomidine 5μg∕kg group ( group Dex2) and dexmedetomidine 10μg∕kg group ( group Dex3) . The model of inflammato-ry visceral pain was established by intraperitoneally injecting 0. 9％ acetic acid 10 ml∕kg in VP, Dex1, Dex2 and Dex3 groups, and the equal volume of normal saline was given instead in group C. At 15 min be-fore intraperitoneal injection, dexmedetomidine 1, 5 and 10μg∕kg were injected via the tail vein in Dex1, Dex2 and Dex3 groups, respectively, and the equal volume of normal saline was given instead in C and VP groups. Behavioral changes of rats were observed within 60 min after the model was established, and viscer-al pain index ( VPI) was calculated. Blood samples were collected from the hearts at 180 min after establis-hing the model for determination of tumor necrosis factor-alpha ( TNF-α) concentrations in serum. The ani-mals were then sacrificed, and colons were obtained for examination of pathological changes with a light mi-croscope. Results Compared with group C, the VPI and serum TNF-α concentrations were significantly increased in VP and Dex1-2 groups, and the serum TNF-αconcentrations were significantly increased ( P<0. 05), and no significant change was found in VPI in group Dex3 (P>0. 05). Compared with group VP, the VPI and serum TNF-α concentrations were significantly decreased (P<0. 05), and the pathological changes of colon tissues were significantly attenuated in group Dex1-3. Compared with group Dex1, the VPI and serum TNF-α concentrations were significantly decreased ( P<0. 01) , and the pathological changes of colon tissues were significantly attenuated in Dex2-3 groups. Compared with group Dex2, the VPI and ser-um TNF-α concentrations were significantly decreased (P<0. 01), and the pathological changes of colon tissues were significantly attenuated in group Dex3. Conclusion Dexmedetomidine pretreatment can miti-gate inflammatory visceral pain in rats.

Objective To evaluate the effect of intrathecal dexmedetomidine on expression of sub-stance P (SP) and c-fos in the spinal dorsal horns of rats with visceral pain. Methods Thirty-two clean-grade healthy adult male Sprague-Dawley rats, weighing 250-300 g, were divided into 4 groups ( n=8 each) using a random number table method: control group (C group), visceral pain group (VP group), dexmedetomidine group (D group) and dexmedetomidine plus atipamezole group (DA group). VP, D and DA groups received intraperitoneal injection of 0. 9％ acetic acid 10 ml∕kg to establish the model of visceral pain, while group C received the equal volume of normal saline instead. At 10 min before the model was es-tablished, dexmedetomidine 20 μl (1μg∕kg) and dexmedetomidine 1μg∕kg plus atipamezole 1μg∕kg (20μl) were intrathecally injected in D and DA groups, respectively, and the equal volume of normal saline 20μl was given instead in C and VP groups. Visceral pain index ( VPI) was recorded at 1 h after intraperito-neal injection, and then rats were sacrificed, and the dorsal horns of the spinal cord ( L4-6 ) were removed for determination of the expression of SP and c-fos by immunohistochemistry. Results Compared with group C, VPI was significantly increased, and the expression of SP and c-fos was up-regulated in VP, D and DA groups (P<0. 05). Compared with group VP, VPI was significantly decreased, and the expression of SP and c-fos was down-regulated in D and DA groups (P<0. 05). Compared with group D, VPI was signifi-cantly increased, and the expression of SP and c-fos was up-regulated in group DA ( P<0. 05) . Conclusion Intrathecal dexmedetomidine reduces the visceral pain through inhibiting the expression of SP and c-fos in the spinal dorsal horns, which is related to the α2-adrenergic receptor in spinal dorsal horns of rats.