A highly distorted ultraelastic chemically complex Elinvar alloy.

The development of high-performance ultraelastic metals with superb strength, a large elastic strain limit and temperature-insensitive elastic modulus (Elinvar effect) are important for various industrial applications, from actuators and medical devices to high-precision instruments1,2. The elastic strain limit of bulk crystalline metals is usually less than 1 per cent, owing to dislocation easy gliding. Shape memory alloys3-including gum metals4,5 and strain glass alloys6,7-may attain an elastic strain limit up to several per cent, although this is the result of pseudo-elasticity and is accompanied by large energy dissipation3. Recently, chemically complex alloys, such as 'high-entropy' alloys8, have attracted tremendous research interest owing to their promising properties9-15. In this work we report on a chemically complex alloy with a large atomic size misfit usually unaffordable in conventional alloys. The alloy exhibits a high elastic strain limit (approximately 2 per cent) and a very low internal friction (less than 2 × 10-4) at room temperature. More interestingly, this alloy exhibits an extraordinary Elinvar effect, maintaining near-constant elastic modulus between room temperature and 627 degrees Celsius (900 kelvin), which is, to our knowledge, unmatched by the existing alloys hitherto reported.

[Application of Rotarex catheter system in femoropopliteal artery stenosis accompanied with thrombosis].

OBJECTIVE: To evaluate the effectiveness and safety of Rotarex catheter system in treating femoropopliteal artery stenosis accompanied with thrombosis. METHODS: From Jun. 2017 to Dec. 2019, the clinical data of 32 femoropopliteal artery stenosis accompanied with thrombosis cases treated with Rotarex catheter system were retrospectively analyzed. There were 23 males and 9 females aged from 50 to 89 years and the mean age was (70.7±10.3) years. Six cases had acute course of disease (≤2 weeks), 17 cases had subacute course of disease (>2 weeks, ≤3 months), and 9 cases had chronic course of disease (>3 months). Mean lesion length was (23.4±13.7) cm, mean occlusion length was (19.9±13.3) cm, and in-stent occlusion 7 cases. The superficial femoral artery (SFA) was involved in 13 cases, the popliteal artery (PA) was involved in 8 cases, and both SFA and PA were involved in the other 11 cases. All the cases were treated with Rotarex catheter system. When necessary, suction with large lumen catheter was enabled. Residual stenosis was treated with percutaneous transluminal angioplasty (PTA). Drug-coated balloon (DCB) was only used in patients with financial status, and stent was used only when it was necessary. Heparin was used for 24 h after procedures, and after that, antiplatelet agents were used. Doppler ultrasonography was taken during the followed-up. RESULTS: Technical success was 100%, and mean procedure time was (107.4±21.5) min. 8F (1F≈0.33 mm) and 6F Rotarex catheter were used in 27 and 5 cases respectively. In 27 cases, forward flow was obtained immediately after debulking with Rotarex catheter, and in the other 5 cases, suction with large lumen catheters were used. PTA was used in all 32 cases. DCB were used in 8 cases, of which 4 were used in in-stent stenosis. Twelve cases were implanted stents. There were no perioperative deaths. The only one procedure related complication was distal embolism. We took out the thrombus with guiding catheter. In all cases, mean hospital stay were (4.6±1.5) d. The ankle brachial index increased from 0.32±0.15 to 0.86±0.10 after treatment (t=-16.847, P < 0.001). The Rutherford stages decreased significantly (Z=-4.518, P < 0.001). All the patients were followed up for 6.0-36.0 months, and the median time was 16.0 months. 2 cases stopped antiplatelet agents, which resulted in acute thrombosis. Another percutaneous mechanical thrombectomy and PTA were taken in one of them. Two cases died of cardiovascular disease during the follow-up, and no amputation was observed. Target lesion restenosis occurred in 7 cases during the follow-up, and target lesion revascularization (TLR) was taken in two of them. CONCLUSION: In treating femoropopliteal artery stenosis accompanied with thrombosis, Rotarex catheter can remove thrombus effectively, and that can expose underlying lesions and reduce stent use and complications rates. It is a safe and effective method.

[Clinical application of Neuroform Atlas stent-assisted coiling in the treatment of unruptured wide-neck intracranial aneurysms].

OBJECTIVE: To assess the safety and efficacy of Neuroform Atlas stent used in treatment of unruptured wide-neck intracranial aneurysms. METHODS: Clinical data of 62 patients with unruptured wide-neck intracranial aneurysms undergoing Neuroform Atlas stent-assisted coiling from August 2020 to September 2021 were retrospectively analyzed. There were 64 aneurysms in those 62 patients. Among them, 25 aneurysms were located at the bifurcation of M1 segment on middle cerebral artery, 16 at the anterior communicating artery, 10 at the C7 segment of internal carotid artery, 5 at the C6 segment of internal carotid artery, 4 at the apex of basilar artery, 3 at the A3 segment of anterior cerebral artery, and 1 at the M2 segment of middle cerebral artery. All the patients underwent Neuroform Atlas stent-assisted coiling, including 49 patients with single stent assisted coiling and 15 patients with dual stents assisted coiling (14"Y"style and 1"X"style). After the procedure, the immediate DSA was performed to evaluate the status of aneurysm occlusion and the parent artery patency. The clinical follow-up was performed 3 months after the operation and evaluated based on the modified Rankin Scale(mRS).DSA image was reviewed at 6 months after operation and Raymond grading scale was used to assess the status of aneurysm occlusion and the parent artery patency. RESULTS: A total of 62 patients with 64 aneurysms were all achieved technical success(100%).The immediate post-procedural Raymond scale was assessed, including Raymond Ⅰ in 57 aneurysms(89.1%, 57/64), Raymond Ⅱ in 6 aneurysms(9.3%, 6/64) and Raymond Ⅲ in 1 aneurysm(1.6%, 1/64). The peri-procedural complications rate was 4.8%(3/62), 2 patients developed intraoperative thrombosis and 1 patient suffered from local subarachnoid hemorrhage. Among them, 55 patients obtained 3 months clinical follow-up after operation and all the patients had good outcomes (mRS≤2), 50 patients with 52 aneurysms were followed up with DSA 6 months after operation, including Raymond Ⅰ in 45 aneurysms(86.5%, 45/52), Raymond Ⅱ in 4 aneurysms(7.7%, 4/52) and Raymond Ⅲ in 3 aneurysms(5.8%, 3/52). CONCLUSION: Neuroform Atlas stent for the treatment of unruptured wide-neck intracranial aneurysms has high safety and good efficacy, and has its advantages over other traditional stents.

[Analysis of the therapeutic efficacy and factors influencing sequential combination of nucleos(t)ide analogues with pegylated interferon alpha for 48~96 weeks in the treatment of patients with chronic hepatitis B].

Objective: To explore the therapeutic efficacy and factors influencing the sequential combination of nucleos(t)ide analogues (NAs) with pegylated interferon alpha (Peg-IFN-α) in the treatment of patients with chronic hepatitis B (CHB). Methods: 144 CHB cases with NAs treatment for more than 1 year, HBV DNA < 20 IU/ml, hepatitis B surface antigen (HBsAg) quantification < 3 000 IU/ml, treated with a sequential combination of Peg-IFN-α treatment for 48 to 96 weeks, and followed up were selected from the Fifth Medical Center of the PLA General Hospital between May 2018 and May 2020. Intention-to-treat analysis was used to measure the HBsAg clearance rate at 96 weeks. The Kaplan-Meier method was used to compute the cumulative HBsAg clearance rate at 96 weeks. Univariate and multivariate logistic regression were used to analyze the factors influencing HBsAg clearance at 48 weeks of sequential combination therapy. Univariate and multifactorial COX proportional hazard models were used to analyze the factors influencing HBsAg clearance following 96 weeks of prolonged PEG-IFN-α treatment. The receiver operating characteristic curve was used to assess the predictive value of factors influencing HBsAg clearance. A Mann-Whitney U test was used to compare the measurement data between groups. The count data was compared using the χ(2) test between groups. Results: 41 (28.47%) cases achieved HBsAg clearance at 48 weeks of sequential combination therapy. The HBsAg clearance rate at 96 weeks was 40.28% (58/144) by intention-to-treat analysis. The Kaplan-Meier method computed that the cumulative HBsAg clearance rate at 96 weeks was 68.90%. Multivariate logistic regression analysis showed that HBsAg quantification at baseline (OR = 0.090, 95%CI: 0.034-0.240, P < 0.001) and a 24-week drop in HBsAg level (OR = 7.788, 95%CI: 3.408-17.798, P < 0.001) were independent predictors of HBsAg clearance in CHB patients treated sequentially in combination with NAs and Peg-IFN-α for 48 weeks. Receiver operating characteristic curve analysis showed that the baseline HBsAg quantification [area under the receiver operating characteristic curve (AUC), 0.911, 95% CI: 0.852-0.952)] and 24-week drop in HBsAg level (AUC = 0.881, 95%CI: 0.814-0.930) had equally good predictive value for 48-week HBsAg clearance, but there was no statistically significant difference between the two (Z = 0.638, P = 0.523). The value of the combination of baseline HBsAg quantification and 24-week drop in HBsAg level (AUC = 0.981, 95%CI: 0.941-0.997) was superior to that of single baseline HBsAg quantification (Z = 3.017, P = 0.003) and 24-week drop in HBsAg level (Z = 3.214, P = 0.001) in predicting HBsAg clearance rate at 48 weeks. Multivariate COX proportional hazards model analysis showed that HBsAg quantification at 48 weeks (HR = 0.364, 95%CI: 0.176-0.752, P = 0.006) was an independent predictor of HBsAg clearance with a prolonged course to 96 weeks of Peg-IFN-α treatment. Conclusion: The HBsAg clearance rate can be accurately predicted with baseline HBsAg quantification combined with a 24-week drop in HBsAg level in patients with CHB who are treated with a sequential combination of NAs and Peg-IFN-α therapy for 48 weeks. Prolonging the course of Peg-IFN-α treatment can enhance the HBsAg clearance rate's capability. An independent predictor of HBsAg clearance is HBsAg quantification at 48 weeks of sequential combination therapy with a prolonged course of 96 weeks of Peg-IFN-α treatment.

[Application of mechanical debulking in arteriosclerosis occlusive disease of lower extremity].

Objective: To evaluate the effect of mechanical debulking in treating arteriosclerosis occlusive disease of lower extremity. Methods: The clinical data of 52 arteriosclerosis occlusive disease of lower extremity cases treated with Rotarex mechanical debulking system from June 2017 to June 2020 at Department of Intervention Vascular Surgery,Peking University Third Hospital were retrospectively analyzed. There were 37 males and 15 females,aged(69.4±10.1)years(range:47 to 89 years).Lesion length was (21.6±12.9)cm(range:4 to 45 cm),occlusion length was (18.5±11.8)cm(range:4 to 45 cm).The lesion was located in iliac artery(IA) in 6 cases,femoral-popliteal artery(FPA) in 42 cases,and both IA and FPA in 4 cases. All the cases were treated with Rotarex mechanical debulking system. Residual stenosis more than 50% were treated with percutaneous transluminal angioplasty(PTA).Drug coated balloon was used in part of them,and stent was used only when it was necessary. The patient's operation, complications, postoperative target vessel restenosis and reoperation were collected. The paired sample t test and rank sum test was used for data comparison and the postoperative target vessel patency rate was analyzed by Kaplan-Meier survival curve. Results: All the 52 cases obtained technical success. Percutaneous transluminal angioplasty was used in all cases,and drug coated balloon were used in 11 cases. Twenty-six stents were implanted in 24 cases (2 cases implanted 2 stents).Nine stents were implanted in IA and 15 in FPA. The length of stents was (11.3±3.3)cm(range:6 to 23 cm).There were 3 procedure related complications: one of them was acute occlusion in an iliac lesion,and thrombectomy was applied urgently,and the result was good. And the other two were distal embolism. The thrombus were took out with guiding catheter. The hospital stay was (4.8±1.9)days. The ankle brachial index increased from 0.34±0.16 to 0.81±0.16 after treatment(t=-25.160,P<0.01).The Rutherford stages decreased from (M(IQR)) 3(1) to 1(1(Z=-6.825,P<0.01).The median followed up time was 19 months(range:6 to 42 months).Two cases stopped antiplatelet agents during follow-up and which result in acute thrombosis 2 weeks and 2 months later respectively. One of them was treated with percutaneous mechanical thrombectomy and the other one was not for gastrointestinal hemorrhage. Four cases died during follow-up,one case died of lung cancer,one died of abdominal infection,and the other 2 cases died of cardiovascular disease,and no amputation was observed. Target lesion restenosis(TLR) more than 50% occurred in 13 cases during the follow-up. All TLR were observed in FPA,and target lesion revascularization was taken in 3 of them. According to Kaplan-Meier survival curve analysis,half-year,1-year and 2-year cumulative patency rates of target vessels in this group was 94.2%,87.4% and 51.4%, respectively. And half-year and 1-year cumulative patency rates just in FPA cases was 92.9% and 84.3%, respectively. Conclusions: Percutaneous mechanical debulking using Rotarex catheter combining PTA can reduce the use of stents in femoral-popliteal artery. It is safe and effective in treating with arteriosclerosis obliterans of lower extremity.

[Radiofrequency obliteration of varicose veins of lower extremity guided by combined venography and ultrasonography].

OBJECTIVE: To explore the technical details and short-term effects of radiofrequency obliteration of varicose veins of lower extremities guided by combined venography and ultrasound. METHODS: Thirty-seven patients with varicose veins of lower extremities were treated with radiofrequency obliteration using Olympus Celon RFiTT® under combined guidance of venography and ultrasound. The indications included varicose veins of lower extremities and reflux of the great saphenous vein confirmed by ultrasound. The contraindications included deep vein thrombosis, cardiac pacemaker, severe cardio- and cerebrovascular diseases or coagulation disorders. Under ultrasound guidance, the saphenous vein around knee level was punctured using a 21G needle, and a 7F sheath was introduced. Through the sheath a venography was made, and an Olympus Celon ProCurve radiofrequency catheter was inserted and advanced to the great saphenous vein under road map, and the catheter tip was positioned at the point 2 cm below the sapheno-femoral junction. The swelling anesthesia was made under ultrasound guidance. Then the radiofrequency obliteration was performed with pressing of the treatment section. The venography was repeated to ensure optimal outcomes. If necessary the radiofrequency obliteration could be repeated once to twice. After that the superficial varicose veins were stripping by small incisions under local anesthesia. After operation, medical decompression stocking was utilized immediately and sustained for three months. The clinical data, intraoperative radiation dose, exposure time and short-term effects were retrospectively analyzed. RESULTS: After the operation, all the patients walked out of the operating room by themselves. The success rate of operation was 100%. The intraoperative radiation dose was 1.78-10.12 mGy (mean 6.56 mGy), and the exposure time was 61-448 s (mean 161 s). By 3 months follow-up, the symptoms were alleviated in all the 37 patients, and the occlusion rate was 100%. No complications such as skin burns, ecchymosis and deep venous thrombosis were found. CONCLUSION: The short-term effects of radiofrequency obliteration using Olympus Celon RFiTT® system in a manner of twice fixed point followed by once reciprocating radiofrequency were satisfactory. Radiofrequency obliteration of great saphenous veins guided by venography and ultrasound has not only the advantages of minimal trauma and rapid recovery, but also the advantages of accurate location, exact effect and avoidance of complications.

[Application of Rotarex mechanical thrombectomy system in acute lower limb ischemia].

OBJECTIVE: To evaluate the effectiveness and safety of Rotarex mechanical thrombectomy system in treating acute lower limb ischemia. METHODS: From December 2017 to December 2019, the clinical data of 23 acute lower limb ischemia cases treated with Rotarex mechanical thrombectomy system were retrospectively analyzed. There were 14 males and 9 females from 53- to 84-year-old patients and the mean age was (69.1±9.1) years. Duration of symptoms was 6 hours to 14 days (median time 7 days). In the study, 8 acute thromboembolism cases and 15 acute thrombosis cases were included (In which, there was one thromboangiitis obliterans case and two in-stent restenosis cases). In 5 cases, the lesions were located above the groin; in 16 cases, the lesions were located below the groin, and in the other 2 cases, the lesions were located both above and below the groin. All the cases were treated with Rotarex mechanical thrombectomy system. When residual stenosis was greater than 50%, percutaneous transluminal angioplasty (PTA) was used, and stent was used only when it was necessary. Heparin was used 24 h after the procedure, and after that, antiplatelet agents were used in acute thrombosis cases, and oral anti-coagulants were used in acute thromboembolism cases. Doppler ultrasonography was taken during the follow-up. RESULTS: In all the 23 cases, there were 22 successful cases and 1 unsuccessful case, the mean procedure time was (68.2±15.6) min. Percutaneous transluminal angioplasty was used in 18 cases, 7 of which were implanted stents (3 stents were implanted in iliac artery and 4 in superficial femoral artery). There were 3 procedure related complications. The first one was arterial wall injury which resulted in contrast medium extravazation, and in this case, we solved it with prolonged balloon inflation. The second one was distal embolism. We took out the thrombus with guiding catheter. The last one was acute occlusion in a stent, and thrombectomy was applied urgently, and the result was good. Mean hospital stay were (3.6±1.7) days. The ankle brachial index (ABI) increased from 0.25±0.10 to 0.85±0.16 after treatment (t=12.901, P < 0.001). All the patients were followed up for 4.0-28.0 months, and the median time was 12.0 months. One patient stopped antiplatelet agents, which resulted in acute thrombosis 2 months later. Another percutaneous mechanical thrombectomy and PTA were taken. In the failed case, the patient suffered amputation above the knee 3 months later and in another case, the patient died of heart failure 8 months after the procedure. Two target lesion restenosis occurred during the follow-up. Because the patients' symptom was not sever, no procedure was taken. CONCLUSION: Percutaneous mechanical thrombectomy using Rotarex catheter is safe and effective in treating acute lower limb ischemia. For one side, it can restore blood flow to the affected limbs quickly, and for the other, it has the characteristics of minimally invasive and good repeatability. So it should be considered that this me-thod can be widely used for acute lower limb ischemia.

[Application of Rotarex mechanical thrombectomy system in treating in-stent restenosis of lower extremity arteriosclerosis obliterans].

OBJECTIVE: To evaluate the role of Rotarex mechanical thrombectomy system in treating instent restenosis of peripheral artery disease (PAD). METHODS: The clinical data of 7 in-stent restenosis (ISR) cases of lower extremity PAD from June 2017 to Dec 2018 were retrospectively analyzed. There were 5 males and 2 females and the mean age was (70.0±7.6) years from 59.0 to 76.0 years. All the cases were treated by Rotarex mechanical thrombectomy system. In the 7 cases, time interval from the previous stent implantation to ischemia recurrence was 1.0 to 72.0 months, and the median time was 6.0 months. The period from ischemia recurrence to endovascular therapy was 3 days to 2 years, and the median time was 62 days. Rotarex mechanical debulking catheter and percutaneous transluminal angioplasty (PTA) were used in all the cases, and the stent was used only when it was necessary. Anticoagulation was used for 24 hours after procedures and then antiplatelet agents were used as usual. Doppler ultrasonography was taken during the followed-up. RESULTS: All the 7 cases were successful in technology, 3 of which were implanted with new stents for the fracture of the old ones. while for the other four cases, no new stent was implanted. The ankle-brachial index (ABI) increased from 0.31±0.08 to 0.86±0.08 after treatment (t=-12.84, P < 0.001). Thrombectomy was applied urgently in one case because of acute thrombosis in the stent, and the result was good. There was no other complications in hospital. All the patients were followed up for 5.0-22.0 months, and the median time was 14.0 months. No death and amputation occurred during the follow-up. One patient stopped antiplatelet agents because of gastrointestinal bleeding, which resulted in acute thrombosis. in-stent restenosis reappeared in 3 cases. CONCLUSION: Debulking using Rotarex catheter is safe and effective in treating in-stent restenosis of PAD, especially in reducing stents implantation, but is not good at dealing with old thrombus and proliferating intima, and can do nothing about fractured stents and hyperplasia of intima, so it needs to be combined with stents and drug coated balloons.

[Early reduction of serum RANTES can predict HBsAg clearance in patients with chronic hepatitis B treated with nucleos(t)ide analogues combined with peginterferon alpha].

Objective: To observe the dynamic changes of serum RANTES during the treatment with nucleos(t)ide analogues combined with pegylated interferon alpha (peginterferon-α), and further analyze the predictive effect of RANTES on HBsAg clearance in patients with chronic hepatitis B. Methods: 98 cases of chronic hepatitis B with quantitative HBsAg < 3 000 IU/ml and HBV DNA < 20 IU/ml after≥1 year NAs treatment were enrolled. Among them, 26 cases continued to receive NAs monotherapy, 72 cases received NAs combined with pegylated interferon alpha therapy. The changes in RANTES during treatment were observed. The receiver operating characteristic curve was used to analyze the early changes of RANTES to predict the HBsAg clearance during 48 weeks. Results: During 48 weeks, 15 cases (20.83%) had achieved HBsAg clearance in combination group, while no patient had achieved HBsAg clearance in NAs group. The overall serum RANTES level had decreased from baseline in NAs and combination group. At week 48, in the combination group, the serum RANTES level was decreased more significantly in patients with HBsAg clearance than patients without. Further analysis showed that, in combination group, HBsAg clearance rate of patients with serum RANTES decreased at week 12 and 24 was higher than patients with elevated (29.17% vs. 4.17%, P = 0.014; 28.00% vs. 4.55%, P = 0.052), and quantitative HBsAg reduction was larger significantly [(1.49 ± 1.26) log(10)IU/ml vs. (0.73 ± 0.81) log(10)IU/ml, P = 0.017; (1.54 ± 1.27) log(10)IU/ml vs. (0.57 ± 0.56) log(10)IU/ml, P = 0.004]. Receiver operating characteristic curve analysis showed that the baseline quantitative HBsAg and the reduction in quantitative HBsAg and serum RANTES during the early period were predictors of HBsAg clearance after 48-week combination therapy. Furthermore, the combination of baseline quantitative HBsAg and 12 - or 24-week reduction of serum RANTES were better predictors of HBsAg clearance than that of baseline quantitative HBsAg combined with HBsAg decrease at week 12 or 24. The area under the receiver operating characteristic curve of the former was 0.925 and 0.939, while that of the latter was 0.909 and 0.929, respectively. Conclusion: Early reduction of serum RANTES at week 12 and 24 can predict HBsAg loss in CHB patients receiving addition of peginterferon-α to ongoing NAs Therapy, so serum RANTES could be one of the key immunological markers for predicting HBsAg clearance.

[Effects of programmed death receptor-1 antibody in patients with hepatitis B-associated liver cancer].

Objective: To investigate the effect of programmed death receptor (PD)-1 antibody therapy in patients with hepatitis B-associated liver cancer. Methods: Data of 29 chronically infected HBV patients with liver cancer who received PD-1 antibody combined with tyrosine kinase inhibitor in the Department of Infectious Diseases of the Fifth Medical Center of PLA General Hospital from March 2020 to January 2021 were selected. At the same time, all of the above-mentioned hepatitis B virus (HBV) patients were treated with nucleos(t)ide analogues. Patients clinical diagnostic data, laboratory test results, tumor response and the incidence of adverse reactions were collected retrospectively to understand the overall safety, therapeutic anti-tumor effect, HBV changes condition and the correlation between HBV changes and anti-tumor PD-1 antibody efficacy, high viral load treatment condition, and HBV reactivation safety issues. Statistical analysis was performed by non-parametric rank sum test. Results: Therapeutic anti-tumor effect and safety profile were good in patients. The complete remission rate was reached 27.6%. Adverse reactions were mostly mild, and the incidence of serious adverse reactions was low. After 12 weeks of follow-up, HBV DNA and hepatitis B surface antigen (HBsAg) was quantitatively decreased (P < 0.05). HBV DNA and HBsAg were decreased more significantly in patients with progressive disease (PD), stable disease (SD) and partial response (PR) (P < 0.05). Five patients with HBV DNA ≥ 10(4) IU/ml had responded well to the tumor treatment without serious adverse reactions. One patient had a slight increase in HBV DNA and alanine aminotransferase, while there was no HBV reactivation and correlated liver damage. Conclusion: Patients with HBV-associated liver cancer who received combined therapy have good anti-tumor efficacy and safety profile. PD-1 treatment has a certain effect on HBV. Compared with non-responders, patients with tumor response have better antiviral treatment efficacy. The safety of treatment in patients with high viral load is manageable, and there are no safety issues related to HBV reactivation.

[Hybrid treatment for symptomatic long-segment chronic internal carotid artery occlusion without stump].

OBJECTIVE: To summarize the preliminary experience of hybrid operation for the treatment of symptomatic long-segment chronic internal carotid artery occlusion (CICAO) without stump. METHODS: Clinical data of 12 patients of symptomatic long-segment CICAO without stump undergoing hybrid operation treatment from July 2015 to December 2017 were retrospectively analyzed. The safety and efficacy of hybrid operation for the treatment of symptomatic long-segment CICAO without stump were preliminarily assessed. CICAO was defined as occlusion time being more than 4 weeks. The primary outcome was defined as any stroke (including ischemic or hemorrhagic) or deaths from any cause after hybrid operation within 30 days. The secondary outcome was defined as successful revascularization and occurrence of >50% in-stent restenosis during the follow-up period. RESULTS: In this group, the symptomatic long-segment CICAO of 11 patients were successfully recanalized. Technical success rate was 91.7% (11/12). The main complication rate was 8.3% (1/12). This patient encountered iatrogenic internal carotid artery cavernous sinus fistula caused by micro-guide wire in the midway of the hybrid operation, the proximal segment of this internal carotid artery was ligated and the iatrogenic internal carotid artery cavernous sinus fistula disappeared in the following digital subtraction angiography image. No patient encountered hemorrhagic stroke and ischemic stroke. No death complications occurred. In this group 10 patients of them were followed up. The follow-up period ranged from 10 to 32 months [mean, (19±9) months]. During the follow-up period, 1 patients developed in-stent restenosis and improved after reoperation of percutaneous transluminal angioplasty by the right size balloon without stenting treatment. CONCLUSION: Hybrid operation for the treatment of highly screened patients with symptomatic long-segment CICAO without stump is safe and effective, could reduce the incidence of complications and improve procedural success rate.

[Effect of liraglutide on glucagon secretion in obese type 2 diabetic patients].

Objective: To investigate the effect of liraglutide on glucagon release in obese type 2 diabetes (T2DM). Methods: A multi-center, prospective, and self-comparison study was conducted in four hospitals in Qingdao. Twenty-four patients with T2DM were selected and treated with liraglutide for 12 weeks. Glucagon levels before and after treatment were detected before and 30 min, 60 min and 120 min after meals. Results: After 12 weeks of treatment, the overall level of glucagon decreased, in which the differences in glucagon levels at 30 min [(220±79) ng/L vs. (203±77) ng/L, P<0.05] and 60 min [(248±119) ng/L vs. (203±82)ng/L, P<0.05] reached significance, respectively, comparing to those before treatment. The area under the curve of glucagon after treatment was significantly lower than that before treatment (438±190 vs. 389±153, P<0.05). In contrast, after treatment, the overall level of C-peptide increased, especially the levels at 30 min [(1.53±1.02) nmol/L vs.(2.03±1.29) nmol/L], 60 min [(1.93±1.19) nmol/L vs. (2.48±1.75) nmol/L] and 120 min [(2.36±1.47) nmol/L vs. (2.96±1.84) nmol/L], all P<0.05. The area under C-peptide curve increased significantly (3.6±2.2 vs. 4.6±2.9, P<0.05). Fasting plasma glucose, postprandial 2 h plasma glucose and glycosylated hemoglobin A1c were all lower than before, and the differences were statistically significant (P<0.05). Waist circumference and body mass index were significantly lower than before (P<0.05). The amount of insulin used for the treatment decreased by approximately 55.1% compared with that before liraglutide, and the difference was statistically significant (P<0.05). Conclusions: Liraglutide inhibits glucagon secretion and lowers blood glucose. It can also reduce body weight, improve islet cell function and reduce insulin use in T2DM.

[Cerebral hyper perfusion syndrome after carotid artery stenting].

OBJECTIVE: To explore the risk factors, clinical characteristics, precaution and treatment of hyper perfusion syndrome (HPS) after carotid artery stenting (CAS). METHODS: From September 2014 to March 2018, the clinical data of 226 patients with severe carotid stenosis (70%-99%) treated with carotid artery stenting (CAS)at Department of Interventional Radiology and Vascular Surgery, Peking University Third Hospital, were analyzed retrospectively．Five of them developed HPS after CAS．The relationship between the clinical baseline data, imaging characteristics, perioperative management and HPS were assessed. RESULTS: In this group, 5 patients of them (2.21%, 5/226) developed HPS after CAS, and 2 patients of them (0.88%, 2/226) were hyper perfusion induced intracranial hemorrhage (HICH). The 5 patients consisted of 4 men and 1 woman whose age ranged from 58 to 74 years. The symptoms of HPS occurred within 4 hours to 3 days after CAS. Among the 5 cases, the clinical manifestations were that 2 cases with headache, 1 case with delirium,1 case with hemiparesis of left limbs, and 1 case with coma(died ultimately).The main manifestations of case 1 and case 2 were headache in the frontal parietal temporal region of the operative side, accompanied by nausea and vomiting. The symptoms were relieved after blood pressure lowering treatment and mannitol dehydration. The main manifestations of case 3 were excitement and delirium. The symptoms were relieved by a small dose of sedatives, also with blood pressure lowering treatment and mannitol dehydration. The initial symptoms of case 4 were excitement and delirium, accompanied by mild headache of the operative side, and hemiplegia of the contralateral limb occurred within a short time. The main manifestation of case 5 was severe headache and went into deep coma within a short time. This patient died of massive cerebral hemorrhage ultimately. CONCLUSION: HPS is an uncommon but serious complication after CAS. Improving our understanding and heightening vigilance of HPS is necessary. The earlier diagnosis, the earlier treatment.

[Mechanical thrombectomy treatment in patients with acute ischemic stroke: a single center study].

OBJECTIVE: To evaluate the effectiveness and safety of mechanical thrombectomy treatment in patients with acute ischemic stroke (AIS),and to explore influential factors of the clinical prognosis preliminarily. METHODS: Clinical data of 26 patients with acute cerebral arterial occlusion treated with mechanical thrombectomy in Peking University Third Hospital from January 2014 to June 2017 were retrospectively collected. The immediate effects of the 26 patients in this group after mechanical thrombectomy treatment were analyzed,The national institutes of health stroke scale (NIHSS) scores between preoperative and at discharge of the 26 patients in this group were compared,and modified Rankin scale (mRS) scores of 90 days post operation were analyzed to assess the prognosis of the 26 patients in this group. RESULTS: (1)In this group, 23 patients (88.5%) achieved vascular recanalization evaluated by thrombolysis in cerebral ischemia scale scores [thrombolysis in cerebral ischemia scale (TICI) scores, 3/2b grades were recognized as vascular recanalization], 19 patients of them reached TICI grade 3 and 4 atients reached TICI grade 2b. In this group 3 patients (11.5%) encountered symptomatic intracranial hemorrhage, 2 patients of them recovered after cerebral hemorrhage absorbed and 1 patient died of massive cerebral hemorrhage. In this group 4 patients (15.4%) died after mechanical thrombectomy treatment,2 patients died of hernia of the brain caused by severe cerebral edema, 1 patient died of symptomatic intracranial hemorrhage and 1 patient died of extensive subarachnoid hemorrhage. (2)The assessment of NIHSS scores at discharge(5.3±2.1)showed significantly lower than those preoperatively(12.6±4.2), P<0.01,and in this group 12 patients (46.2%) achieved favourable prognosis (defined as mRS scores 0-2), 6 patients of them reached mRS 0 score,4 patients reached mRS 1 score and 2 patients reached mRS 2 scores. CONCLUSION: Mechanical thrombectomy with stent retriever contributed to a high rate of vascular recanalization and favourable prognosis,but some patients had poor prognosis, suggesting that we should screen the enrolled patients strictly.

[Application of Neuroform EZ stent in the treatment of severe intracranial arterial stenosis with complex symptomatic].

OBJECTIVE: To assess the safety and efficacy of Neuroform EZ stent used in treatment of symptomatic complex severe intracranial atherosclerotic stenosis (ICAS). METHODS: Clinical data of 18 patients with symptomatic complex severe ICAS undergoing Neuroform EZ stent angioplasty from January 2016 to December 2017 were retrospectively analyzed. All the lesions of the patients in this group were considered as complex ICAS, i.e. with severe tortuous access, long (>10 mm) or occlusive or bifurcation lesions, with concurrent aneurysms near the stenotic lesion. The primary outcome was defined as any stroke (including ischemic or hemorrhagic) or deaths from any cause after stenting procedure within 30 days. The secondary outcome was defined as successful revascularization and occurrence of >50% in-stent restenosis during the follow-up period. RESULTS: All the 18 patients achieved technical success (100%) and mean stenosis rate was reduced from 85%±7% to 18%±6%. Of the 18 patients included, the 30-day stroke or death was 5.6% (1/18), which presented as basal ganglia region infarction in a patient with tandem lesions on the left vertebral artery. There was no hemorrhagic and death complications that occurred in the patients of this group. One concurrent aneurysm was embolized with micro coil (stent assisted) by stages after 1 month. In this group 12 patients were followed up with digital subtraction angiography (DSA) after hospital discharge. The follow-up period ranged from 8 months to 26 months [mean: (16±8) months]．During the follow-up period 2 patients in the 12 patients (2/12, 16.7%) developed in-stent restenosis (ISR) confirmed by DSA, and one of them was symptomatic restenosis and restored unobstructed blood flow after balloon angioplasty. CONCLUSION: Neuroform EZ stent for the treatment of highly screened symptomatic complex severe ICAS is safe and effective. It has its advantages over traditional stent.

[Downregulation of large conductance calcium-activated potassium channels in paraventricular nucleus contributes to sympathoexcitation in rats with chronic heart failure].

Objective: To elucidate the association between large conductance calcium-activated potassium channels (BKCa) in the paraventricular hypothalamic nucleus (PVN) and sympathetic outflow in rats with chronic heart failure (CHF) . Methods: Male Wistar rats (6-7 weeks old) were randomized to sham operated group and CHF group (coronary artery ligation) . Two weeks after operation, BKCa inhibitor Iberiotoxin (IBTX) was infused into PVN by osmotic minipumps, rats were divided into following groups: sham+aCSF, CHF+aCSF, sham+low dose IBTX (0.125 nmol/nl) , CHF+low dose IBTX, sham+moderate dose IBTX (1.25 nmol/nl) , CHF+moderate dose IBTX, sham+ high dose IBTX (12.5 nmol/nl) , and CHF+high dose IBTX (n=6 each) . Additional rats were grouped as follows: sham+vehicle, sham+KCNMB4 knockdown (by rAAV2-KCNMB4 shRNA virus injection in PVN) , CHF+vehicle, CHF+ KCNMB4 knockdown group (n=6 each) . The cardiac function was determined by echocardiography, left ventricular hemodynamics were measured invasively, renal sympathetic nerve activity (RSNA) was recorded at 6 weeks after coronary artery ligation or sham operation. The contents of norepinephrine (NE) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) in plasma were determined by enzyme-linked immunosorbent assay. The protein and mRNA expression of KCNMB4 in PVN were measured by immunofluorescence staining, Western blot, and real-time PCR, mRNA expression of BKCa in PVN was detected by real-time PCR. Results: Compared with the sham operation group, the cardiac function of the heart failure group was significantly reduced (P<0.05) , and the plasma NE and the serum NT-proBNP were significantly elevated (P<0.05) . The protein and mRNA expression of KCNMB4 in PVN were obviously down-regulated in CHF rats (P<0.05) . After perfusion of IBTX or KCNMB4 knockdown by microinjection of rAAV2-KCNMB4 shRNA virus,right ventricular weight/body weight and lung weight/body weight ratio as well as left ventricular end-diastolic diameter were increased and left ventricular ejection fraction was decreased (all P<0.05) , the sympathetic driving indexes was increased in sham rats, changes of these parameters further aggravated in CHF rats (P<0.05) . KCNMB4 knockdown further downregulated protein expression in PVN of CHF rats. Conclusion: Downregulation and blunted function of BKCa in PVN may contribute to sympathoexcitation and deterioration of cardiac function in rats with chronic heart failure.

Directed evolution of an ultrastable carbonic anhydrase for highly efficient carbon capture from flue gas.

Carbonic anhydrase (CA) is one of nature's fastest enzymes and can dramatically improve the economics of carbon capture under demanding environments such as coal-fired power plants. The use of CA to accelerate carbon capture is limited by the enzyme's sensitivity to the harsh process conditions. Using directed evolution, the properties of a ß-class CA from Desulfovibrio vulgaris were dramatically enhanced. Iterative rounds of library design, library generation, and high-throughput screening identified highly stable CA variants that tolerate temperatures of up to 107 °C in the presence of 4.2 M alkaline amine solvent at pH >10.0. This increase in thermostability and alkali tolerance translates to a 4,000,000-fold improvement over the natural enzyme. At pilot scale, the evolved catalyst enhanced the rate of CO2 absorption 25-fold compared with the noncatalyzed reaction.

[Significance of renal filtration fraction evaluation of renal artery stenting for atherosclerotic renal artery stenosis treatment].

OBJECTIVE: To investigate the significance of filtration fraction (FF) and renal artery stenting in the treatment of atherosclerotic renal artery stenosis. METHODS: In the study, 42 cases of renal artery stenosis were treated with 52 renal artery stent implantation. Percutaneous transluminal renal angioplasty and stent (PTRAS) of the patients' health side kidney, ipsilateral kidney (renal) glomerular filtration rate (GFR), renal effective renal plasma flow effective renal plasma flow (ERPF), kidney filtration fraction changes of preoperative and postoperative serum creatinine (SCR) and the changes in the patients with blood pressure (SBP) and the changes after taking antihypertensive drugs were observed and analyzed. RESULTS: The 52 cases of renal artery stent implantation were all successful. Preoperative ipsilateral GFR was significantly lower than that of normal side (t=-3.989, P=0.000); preoperative ipsilateral ERPF was significantly lower than the contralateral side (t=-4.926, P=0.000). On both sides, the overall FF values were equal (t=1.273, P=0.207). Postoperative ipsilateral renal GFR was increased, but there was no statistical difference (t=-1.411, P=0.164). Postoperative ipsilateral renal ERPF was increased significantly (t=-4.954, P=0.000), and FF lower (closer to the normal value (t=3.274, P=0.002). Postoperative side GFR was significantly reduced (t=2.569, P=0.000), the contralateral ERPF was significantly reduced (t=3.889, P=0.001), and FF had no significant change (t=-0.758, P=0.454). Postoperative side GFR was lower than that of the contralateral (t=-3.283, P=0.002) and postoperative side ERPF was still lower than that of the contralateral (t=-3.351, P=0.001), but on both sides, the FF values were equal (t=-0.361, P=0.719). Preoperative FF was relatively normal in the patients with kidney, and the postoperative FF value change was small (t=0.799, P=0.430); preoperative FF was significantly higher in the patients with kidney, and the postoperative FF value was lower than the preoperative (normal value, t=5.299, P=0.000). Postoperative overall serum creatinine was significantly decreased (t=2.505, P=0.016); but for the patients with unilateral renal artery stenosis, the changes in serum creatinine had no statistical difference (t=1.228, P=0.299); and for the patients with bilateral renal artery stenosis and serum creatinine compared with the preoperative, the changes were decreased significantly (t=2.518, P=0.030); postoperative blood pressure (SBP) was significantly decreased compared with that before operation (t=8.945, P=0.000); antihypertensive drugs taken were decreased significantly compared with the preoperative (t=5.280, P=0.000). CONCLUSION: For the patients with renal artery stenosis, FF is a useful index to understand the pathophysiological process of renal ischemia. Whether preoperative FF is significantly increased or FF is relatively normal, should be regarded as the indications of renal artery stent implantation.

[Randomized controlled trial to superficial femoral artery recanalization for lower extremity arteriosclerosis obliterans].

OBJECTIVE: To evaluate the safety and effectiveness of neglecting superficial femoral artery (SFA) recanalization for chronic lower extremity arteriosclerosis obliterans (ASO). METHODS: Thirty-six cases treated for severe stenosis or occlusion of superficial femoral artery resulted from ASO were randomly divided into 2 groups. Twenty of them were treated by endovascular reconstruction of superficial femoral artery and the other 16 cases were not treated with their superficial femoral artery, but were only treated with the accompanied iliac and/or profunda femoral artery lesion. RESULTS: There was no significant difference between the two groups on mean age, gender, ABI before treatment, accompanied diseases, Rutherford classification and trans-atlantic inter-society consensus (TASC) classification (P>0.05).One week after operation, the reconstruction group had better marked effect and total effective rate [75.0% vs.12.5%(P<0.001); 90.0% vs. 37.5%(P=0.001)] and lower no effective rate [10.0% vs. 62.5%(P=0.001)], There was no significant difference between the two groups on effective rate [15.0% vs. 25.0%(P=0.675)]. The deteriorate cases in both groups were zero, and there was no morbidity of complications and death in both groups during the perioperative period. In the 3-month follow up, the reconstruction group had a better marked effect rate [65.0% vs.25.0%(P=0.017)];There was no significant difference between the two groups on the effective rate, no effective rate and total effective rate [20.0% vs.43.8%(P=0.124); 15.0% vs.31.3%(P=0.422); 85.0% vs.68.8%(P=0.422)]. The deteriorate cases and morbidity of complications and death in both groups during the perioperative period were still zero. In the 6- and 12-month follow ups, there were no significant differences between the two groups on marked effect and total effective rate [60.0% vs.37.5%(P=0.180), 80.0% vs.87.5%(P=0.672); 60.0% vs.43.8%(P=0.332), 85.0% vs.87.5% (P=1.000)]. The deteriorate case was zero in both groups, and there was no morbidity of complications and death in both groups. The limb salvage rate in both groups was 100% during the whole follow up period. The reconstruction group had a higher cost[(53 367.4±24 518.3) yuan vs.(30 397.5±15 354.4) yuan(P=0.011)]. There were 8 cases of SFA restenosis/ reocclusion during the follow up,three of which accepted another endovascular treatment, and the reoperation rate was 15.0%. while in the nonreconstruction group, there was no case that needed another endovascular therapy, and the reoperation rate was zero. CONCLUSION: Only dealing with accompanied iliac and profunda artery lesion and neglecting superficial femoral artery reconstruction is a safe, effective and inexpensive therapy for chronic lower extremity arteriosclerosis obliterans, and should be the preferred alternative for some patients.