[Correlation between postoperative microstructural changes in cerebral white matter and early postoperative cognitive function in patients undergoing meningioma resection]

Objective: To analyze the correlation between microstructure changes in cerebral white matter before and after surgery and early postoperative cognitive function in patients undergoing meningioma resection. Methods: A total of 17 patients who underwent their first meningioma resection at Xuanwu Hospital of Capital Medical University from April 2022 to April 2023 were prospectively included as observation group, with 5 males and 12 females, aged (56.4±7.3) years. Another 15 age- and education-matched patients with cerebral benign tumor were recruited as control group during the same period, with 5 males and 10 females, aged (55.2±8.0) years. Neuropsychological tests (NST), mainly including auditory verbal learning test of Huashan version (AVLT-H), the Montreal cognitive assessment-basic (MoCA-B), clock drawing task-30 (CDT-30), shape trails test-B (STT-B) and animal fluence test (AFT), were conducted at 1 day before surgery, 1 day and within 3-4 days after surgery in the observation group. Simultaneously, magnetic resonance imaging (MRI) scans were performed to collect diffusion tensor imaging (DTI) images at 1 day before surgery and within 3-4 days after surgery. The same NST were conducted at 1 day, 3 days and 6 days after admission in the control group to adjust for learning effects from repeated tests. The microstructure changes of the whole brain white matter were evaluated at the group level by using tract-based spatial statistics (TBSS) technology, including changes of fractional anisotropy (FA), mean diffusion (MD), axial diffusion (AD), and radial diffusion (RD). Then, correlation was performed between DTI indicators with statistically significant and cognitive function. Results: After adjusting for the learning effects, the AVLT-H (R), MoCA-B, and CDT-30 scores decreased, and the evaluation time of STT-B prolonged after surgery in patients with meningioma. And their perioperative decreased values were -0.78 (95%CI:-3.28--0.28) points, -2.22 (95%CI:-4.22--0.72) points, -2.74 (95%CI:-5.29--0.19) points, and 61.49 (95%CI: 5.71-117.27) seconds, respectively, with statistically significant differences (all P<0.05). Group level analysis of TBSS based on DTI images showed decreased FA mainly in the right superior cerebellar peduncle, left posterior limb of internal capsule and genu of corpus callosum, and increased RD mainly in the left anterior corona radiata in patients undergoing meningioma resection, with statistically significant differences (all PFWE<0.05). Linear correlation showed that the perioperative decreased values of FA in genu of corpus callosum and right superior cerebellar peduncle were positively correlated with the perioperative decreased values of AVLT-H (L) after adjusting for learning effects (r=0.72, 0.52, all PFWE<0.05). Conclusions: Patients undergoing meningioma resection are at risk of postoperative cognitive decline. Perioperative decreased values of FA in genu of corpus callosum and right superior cerebellar peduncle based on DTI images are positively correlated with the perioperative decreased values of AVLT-H (L) after adjusting for learning effects.

[Clinical efficacy of enhanced recovery after surgery in atrial caval shunting for type Ⅱ Budd-Chiari syndrome]

Objective: To investigate the clinical efficacy of enhanced recovery after surgery(ERAS) in atrial caval shunting (ACS) for type Ⅱ Budd-Chiari syndrome(BCS). Methods: The clinical data of patients underwent ACS for type Ⅱ BCS in the Henan Province People's Hospital from January 2014 to June 2016 were prospectively analyzed.Randomized and single-blind, controlled study was performed among the patients, and all of them underwent ACS and were divided into control group (patients underwent traditional perioperative management) and ERAS group (patients underwent ERAS perioperative management) based on a random number table.Operational and postoperative data, levels of inflammatory cytokines, stress state evaluation and postoperative complications were observed.The comparison between the two groups was evaluated with an independent sample t test.The trend analyses for variables were done using repeated measures ANOVA.The count data were analyzed using the chi-square test or Fisher exact. Results: Eighty-two patients were screened for eligibility, and allocated into the control group (40 patients) and the ERAS group (42 patients). All patients underwent ACS successfully with no death.Comparison of intraoperative status: operation time, volume of intraoperative blood and number of patients receiving blood transfusion were (211.0±12.9) minutes vs. (207.7±10.7) minutes, (167.5±28.3) ml vs. (165.0±28.4) ml and 3 cases vs. 1 case between the control group and the ERAS group, respectively, showing no difference between the two groups (t=0.90, 0.29, χ²=0.32, all P>0.05). Comparison of postoperative status: time of gastric tube removal, time of catheter removal, time of chest tube, time to flatus, time of food intake, duration of postoperative infusion, duration of postoperative hospital stay and numeric rating scale were (3.7±0.5)days vs. (0.0±0.0)days, (2.3±0.7)days vs. (1.4±0.5)days, (3.7±0.7)days vs. (2.3±0.5)days, (75.2±3.8)hours vs. (46.6±4.2)hours, (75.7±4.7)hours vs. (21.4±2.1)hours, (10.0±1.0)days vs. (5.8±0.9)days, (11.4±1.0)days vs. (7.8±0.6)days, 2.9±0.4 vs. 1.9±0.6 between the control group and the ERAS group, respectively, with statistically differences (t=35.03, 4.36, 8.10, 22.89, 47.78, 14.75, 14.22, 6.13, all P<0.05). Stress state evaluation: the levels of IR were (2.7±0.1) vs.(2.7±0.1), (8.8±0.7) vs. (5.2±0.3), (11.0±0.5) vs. (7.3±0.5), (4.9±0.2) vs. (3.9±0.1), and the levels of C-reaction protein were (14.6±1.3)mg/L vs.(14.6±1.1) mg/L, (101.2±13.6) mg/L vs. (89.5±6.9) mg/L, (62.7±8.6) mg/L vs. (56.4±8.4) mg/L, (46.4±6.7) mg/L vs. (40.0±5.6) mg/L from pre-operation to postoperative day 1, 3 and 5 between the control group and the ERAS group, respectively, with statistically significant differences in changing trends(F=136.61, 4.97, both P<0.05). Comparisons of levels of inflammatory cytokines: the levels of IL-6 were (43.1±2.7) ng/L vs. (43.6±3.6) ng/L, (135.1±6.4) ng/L vs. (117.4±5.7) ng/L, (145.4±6.7) ng/L vs. (128.5±5.5) ng/L, (93.3±3.7) ng/L vs. (88.0±3.9) ng/L, and the levels of TNF-α were (10.4±0.3)mmol/L vs. (10.4±0.3) mmol/L, (14.4±0.4) mmol/L vs. (12.6±0.4) mmol/L, (15.6±0.4) mmol/L vs. (13.8±0.4) mmol/L, (12.3±0.7) mmol/L vs. (11.4±0.6) mmol/L from pre-operation to postoperative day 1, 3 and 5 between the control group and the ERAS group, respectively, with statistically significant differences in changing trends (F=15.15, 21.45, both P<0.05). Comparison of postoperative complications: incidence of complications was 30.0%(12/40) in the control group and 11.9%(5/42) in the ERAS group, and the numbers of patients with nausea and vomiting, respiratory complications and cardiovascular complications were 4, 3, 5 cases in the control group and 3, 1, 1 case in the ERAS group, respectively, showing statistically differences in the incidence of complications(χ²=4.08, P<0.05). All the 82 patients were followed up for 2 to 22 months (median time, 12 months), no patients received reoperation or re-admitted to the hospital duo to complications. Conclusion: ERAS management in the perioperative period of ACS for BCS is beneficial to postoperative recovery of patients, and can relieve postoperative stress state and inflammatory response, reduce the duration of hospital stay, and incidence of postoperative complications.

Association of the IGF-1 rs35767 and rs972936 polymorphisms with the risk of osteoporosis in a Chinese postmenopausal female population

The aim of our study was to conduct a case-control study in a Chinese postmenopausal population to evaluate the roles of the IGF-1 rs35767 and rs972936 polymorphisms on bone mineral density (BMD) levels and osteoporosis risk. A total of 272 consecutive postmenopausal women with a primary diagnosis of osteoporosis and 272 controls were enrolled in the study between 2012 and 2014. The polymerase chain reaction-restriction fragment length polymorphism method was used to genotype the rs35767 and rs972936 IGF-1 polymorphisms. By comparing the demographic characteristics between patients and controls, patients with osteoporosis were found to be more likely to have a habit of alcohol drinking (P = 0.023). Furthermore, the BMD levels of the L1-L4 vertebrae, femoral necks, total hips, and trochanters in patients with osteoporosis were significantly lower than those in controls. By conditional regression analysis, we found that the IGF-1 rs2288377 and rs972936 gene polymorphisms were not associated with the risk of osteoporosis (P < 0.05). However, the CT+TT genotype of rs35767 and the AG+GG genotype of rs972936 were significantly associated with lower BMD levels in the femoral neck. Overall, our study suggests that IGF-1 rs2288377 and rs972936 gene polymorphisms do not influence the risk osteoporosis.

Green Strength in Emulsion SBR

The present study and that published previously show that crosslinks based on quaternary ammonium halide salts introduced into emulsion SBR-type polymers confer green strength on blends with other compatible rubbers. The crosslink density employed did not exceed 1 link per 3000 combined monomer groups, equivalent to two links per weight-average polymer chain. Judging by the positive slopes of stress-strain curves, green strength obtained in this manner will persist up to at least 50°C. The crosslinks can be broken by mechanical shear and will re-form under resting conditions during times ranging from days at room temperature to minutes at 150°C. Prolonged mechanical shear in laboratory mixing equipment causes progressive loss of modulus and reduction in the slope of the stress-strain curves of compounds containing these labile crosslinks. Similar effects are observed in corresponding control compounds containing no labile crosslinks, but the initial advantage of the crosslinked compounds is progressively reduced and may be lost if shearing is sufficiently prolonged. Available evidence suggests that the principal cause of loss of modulus through shear is selective breakdown of the high molecular weight fraction of the base polymer. The breakdown of the longer chains, which are those most likely initially to carry three or more crosslinks, eliminates most of the network structure responsible for enhanced modulus. Whether chemical effects contribute to loss of modulus remains to be determined, but the evidence suggests that any such effects will be of lesser importance. Because the shear encountered in small laboratory mixing devices differs from that in full-scale factory equipment and stress-strain curves may not reliably predict green-stock behavior, the significance of the present findings can only be determined by factory trials. It is evident, however, that for the most efficient utilization of high green-strength SBR, exposure of the crosslinked SBR component to mechanical shear during mixing should be held to a minimum. On the other hand, to achieve smooth sheets or profiles at the forming stage, the final compound should be subjected briefly to a high degree of shear at as low a temperature as practicable, to break the labile crosslinks in the stock. Green strength will be recovered during subsequent rest periods. The present study suggests that these conditions should be readily achieved in a calendering operation, such as normally used for preparing carcass plies. However, to a greater extent than in most polymer developments, the final proving ground for applications for this new modification of SBR must be full-scale factory trials.

A STUDY OF THE VAPOR PHASE REACTION OF OZONE WITH OLEFINS IN THE PRESENCE AND ABSENCE OF MOLECULAR OXYGEN

Relative rates of reaction of ozone with a number of olefins in the vapor phase have been determined at room temperature in the presence and absence of molecular oxygen. In the absence of oxygen the rates appear to follow more closely an electrophilic trend, although some of the deviations observed previously in the presence of oxygen still persist to some extent. The ratio of olefin to ozone consumed is unity in the absence of oxygen and varies from about 1.4 to 2 in its presence. In the presence of molecular oxygen, therefore, a secondary attack on the olefins takes place as well. The yields of products are similarly affected.