Sub-satisfactory stenting recanalization of severe vascular stenosis of the posterior circulation can significantly improve cerebral hemodynamic perfusion

PURPOSE

To investigate the effect of sub-satisfactory stenting recanalization of severe vascular stenosis of the posterior circulation on cerebral hemodynamic perfusion.

MATERIALS AND METHODS

Patients with severe vascular stenosis of the posterior circulation who had undergone three-dimensional cerebral angiography before and after stenting were retrospectively enrolled. Computational fluid dynamic (CFD) analysis of hemodynamic parameters at the stenosis, perforating branch, and normal arterial segments proximal and distal to the stenosis were performed.

RESULTS

Sixty-two patients with basilar artery stenosis aged 60.9 ± 9.6 years were enrolled, and stent angioplasty resulted in the reduction of stenosis degree from 85.3 ± 7.2% before to 18.6 ± 6.4% after stenting. After stenting, at the proximal normal artery, the total pressures had significantly (P < 0.05) decreased, whereas all the other parameters (WSS, cell Reynolds number, velocity, vorticity, turbulence intensity, turbulence kinetic energy and dissipation rate) had significantly (P < 0.05) increased. At the stenosis, all hemodynamic parameters had significantly decreased. At the stenosis perforating branch, the WSS, cell Reynolds number, velocity, and vorticity were all significantly decreased, and the total pressure, turbulence intensity, kinetic energy, and dissipation rate were all significantly increased. At the distal normal artery, the total flow pressure (perfusion pressure) and velocity were both significantly (P < 0.05) increased, and the total pressure, WSS, cell Reynolds number, vorticity, turbulence intensity, kinetic energy, and dissipation rate were all significantly (P < 0.05) decreased. The hemodynamic parameters after stenting were closer to those after virtual stenosis repair at all measurements.

CONCLUSION

Sub-satisfactory recanalization has significantly restored the stenosis and improved the hemodynamic parameters near the stenosis and at the root of the perforating branch, thus significantly improving the cerebral perfusion, similar to the changes of hemodynamic status and cerebral perfusion after virtual removal of the vascular stenosis. This may indicate the good effect of sub-satisfactory stenting recanalization of the vascular stenosis at the posterior circulation.

Safety and efficacy of enterprise stenting for symptomatic atherosclerotic severe posterior circulation stenosis

PURPOSE

To investigate the safety and efficacy of Enterprise stent angioplasty and risk factors for the prognoses in treating symptomatic severe posterior circulation atherosclerotic stenosis (SSPCAS).

MATERIALS AND METHODS

Patients with SSPCAS who were treated with the Enterprise stent angioplasty were retrospectively enrolled. The clinical data, peri-procedural complications, postoperative residual stenosis, in-stent restenosis and recurrent stroke at follow-up were analyzed.

RESULTS

262 patients with 275 stenotic lesions treated with the Enterprise stent angioplasty were enrolled. The stenosis degree was reduced from 86.3 ± 6.2% before to 19.3 ± 5.4% after stenting. Complications occurred in 14 (5.3%) patients. Clinical follow-up was performed in 245 (93.51%) patients for 16.5 ± 7.3 months. During 1 year follow-up, 7 patients (2.9%) had recurrent symptoms, including 4 patients with stenting in the intracranial vertebral artery and 3 in the basilar artery. Imaging follow-up was conducted in 223 (85.11%) patients. In-stent restenosis was present in 35 patients (15.7%), with the restenosis rate of 26.4% (n = 23) in the intracranial vertebral artery, which was significantly (P < 0.001) greater than in the basilar artery (8.8%). Six patients (17.1%) with in-stent restenosis were symptomatic. The stenotic length was the only significant (P = 0.026 and 0.024, respectively) independent risk factor for 1 year stroke or death events and in-stent restenosis.

CONCLUSION

The Enterprise stent can be safely and efficaciously applied in the treatment of symptomatic severe posterior circulation atherosclerotic stenosis, with a relatively low rate of in-stent restenosis and recurrent stroke within 1 year. The stenotic length was the only significant independent risk factor for 1 year stroke or death events and in-stent restenosis.

Back focal plane imaging for light emission from a tunneling junction in a low-temperature ultrahigh-vacuum scanning tunneling microscope

We report the design and realization of the back focal plane (BFP) imaging for the light emission from a tunnel junction in a low-temperature ultrahigh-vacuum (UHV) scanning tunneling microscope (STM). To achieve the BFP imaging in a UHV environment, a compact "all-in-one" sample holder is designed and fabricated, which allows us to integrate the sample substrate with the photon collection units that include a hemisphere solid immersion lens and an aspherical collecting lens. Such a specially designed holder enables the characterization of light emission both within and beyond the critical angle and also facilitates the optical alignment inside a UHV chamber. To test the performance of the BFP imaging system, we first measure the photoluminescence from dye-doped polystyrene beads on a thin Ag film. A double-ring pattern is observed in the BFP image, arising from two kinds of emission channels: strong surface plasmon coupled emissions around the surface plasmon resonance angle and weak transmitted fluorescence maximized at the critical angle, respectively. Such an observation also helps to determine the emission angle for each image pixel in the BFP image and, more importantly, proves the feasibility of our BFP imaging system. Furthermore, as a proof-of-principle experiment, electrically driven plasmon emissions are used to demonstrate the capability of the constructed BFP imaging system for STM induced electroluminescence measurements. A single-ring pattern is obtained in the BFP image, which reveals the generation and detection of the leakage radiation from the surface plasmon propagating on the Ag surface. Further analyses of the BFP image provide valuable information on the emission angle of the leakage radiation, the orientation of the radiating dipole, and the plasmon wavevector. The UHV-BFP imaging technique demonstrated here opens new routes for future studies on the angular distributed emission and dipole orientation of individual quantum emitters in UHV.

Endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery

Purpose

The study aimed to investigate the safety, effect, and risk factors of endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery (SNOVA).

Materials and methods

Patients with SNOVA were retrospectively enrolled and treated with endovascular recanalization. The clinical data, endovascular treatment, peri-procedural complications, and follow-up outcomes were analyzed.

Results

A total of 88 patients were enrolled, with an interval to recanalization of 2-89 days (median 23) and an mRS of 2-5 (median 3 and IQR 1). Occlusion was in the intracranial vertebral artery in 68 (77.27%) patients and basilar artery in 20 (22.73%), with an occlusion length of 4.5-43.7 mm (mean 18.3 ± 8.8). Endovascular recanalization was successful in 81 (92.0%) patients. Post-dilatation was performed in 23 (28.4%) patients. After stenting, the residual stenosis was 10%-40% (mean 20.2% ± 7.6%). Peri-procedural complications occurred in 17 (19.3%) patients, with a mortality rate of 5.7%. In total, 79 (95.18%) patients underwent follow-up 5-29 (mean 16.9 ± 5.5) months later, with an mRS score of 0-6 (median 1 and IQR 1) at follow-up, being significantly (p < 0.0001) better than that at discharge. Stroke occurred in 9 patients (11.4%) in 1 year. In-stent restenosis occurred in 19 (25.33%) patients. Significant (p < 0.05) independent risk factors were blunt occlusion for successful recanalization, duration to recanalization and blunt occlusion for peri-procedural complications, and post-dilatation for both in-stent restenosis and 1-year stroke or death events.

Conclusion

Endovascular recanalization of symptomatic non-acute occlusion of the vertebrobasilar artery is feasible even for a long occlusion segment, with a high recanalization rate, a low complication rate, and a good prognosis. Blunt occlusion and duration from the onset to recanalization may affect successful recanalization and peri-procedural complications while post-dilatation may affect in-stent restenosis and prognosis.

Effects of carotid artery stenting on cognitive impairment in patients with severe symptomatic carotid artery stenosis

The effect of carotid artery stenting and medication on improvement of cognitive function in patients with severe symptomatic carotid artery stenosis is unknown. To investigate the effect of stenting compared with medication alone for severe carotid atherosclerotic stenosis on cognitive impairment. Patients with carotid stenosis and cognitive impairment were prospectively randomly divided into 2 groups of stenting or medication alone. Cognitive function was evaluated with the Montreal cognitive assessment (MoCA), Mini-Mental State Examination, and Barthel Index of Activities of Daily Living (BI). Continuous data in normal distribution were tested with the t-test but with the Mann-Whitney U test if not in normal distribution. Categorical data were presented as frequency and percentages and tested with the Fisher exact test. A P value < .05 was regarded as statistical significant. Carotid artery stenting was successfully performed in all patients (100%) in the stenting group. Compared with before treatment, the Mini-Mental State Examination, MoCA and BI scores at 6 months in the medication alone group and at 1, 3, and 6 months in the stenting group were significantly (P < .005) improved. The stenting group had significantly (P < .05) better scores than the medication alone group at the same time. At 6-month follow-up, the visuospatial/executive functions (3.69 ± 1.42 vs 2.42 ± 1.23), attention (5.24 ± 1.52 vs 3.63 ± 1.47), and language (2.64 ± 0.71 vs 1.96 ± 0.69) were significantly (P < .05) improved in the stenting group compared with the medication alone group. Carotid artery stenting may significantly improve cognitive impairment and neurological function compared with medication alone in patients with severe carotid atherosclerotic stenosis concurrent with cognitive impairment.

Endovascular recanalization of extensively-thrombosed cerebral venous sinuses in early pregnancy: A case report

RATIONALE

The incidence of pregnancy-related cerebral venous sinus thrombosis (CVST) is rare, and cerebral hemorrhage caused by CVST in the early pregnancy period is even rarer. Only 3 cases of cerebral hemorrhage caused by CVST had been reported in the early pregnancy period in the literature. In this study, we reported successful endovascular treatment of such a case.

PATIENT CONCERNS

A 27-year-old woman presented with rapidly progressive neurologic decline in her second pregnancy for 8 weeks. She was afebrile and completely conscious, without neurological deficits. She did not have any previous history of venous thrombosis, hematologic, or autoimmune diseases.

DIAGNOSIS

Urgent brain computed tomography demonstrated parietal-occipital hemorrhage surrounded by a large hypodense area and full brain swelling. Magnetic resonance venography showed complete occlusion of the right sigmoid sinus, transverse sinus, and two-thirds of the superior sagittal sinus. Transvaginal sonography demonstrated early intrauterine pregnancy, with the size of gestation sac being 6 × 7 × 6 mm and the fetal heart not being detected. CVST-related cerebral hemorrhage was confirmed based on the clinical and imaging data.

INTERVENTIONS

The CVST in this pregnant woman was treated endovascularly with a 6 Fr Navien catheter for aspiration, thrombolysis, and anticoagulation.

OUTCOMES

Ten days after treatment, the cerebral hemorrhage had gradually been absorbed. Follow-up angiography performed 2 weeks later demonstrated complete recanalization of her cortical veins and sinuses. Two months later, the patient was completely recovered without cognitive or neurological dysfunction.

LESSONS

Pregnancy-related CVST can be successfully treated with a combined endovascular approach of aspiration, thrombolysis, and anticoagulation to complete recovery.

Small Unruptured Intracranial Aneurysms Can Be Effectively Treated With Flow-Diverting Devices

Purpose

To investigate the effect and safety of flow diverters in the management of small (<10 mm in diameter) unruptured intracranial aneurysms.

Materials and Methods

One hundred and ten patients with 145 small intracranial aneurysms treated with flow diverters were retrospectively enrolled. The clinical, endovascular, and follow-up data were analyzed.

Results

One hundred twenty-one flow diverters were deployed for the treatment of 145 small intracranial aneurysms in 110 patients, and the stenting success rate was 99.1%. In 133 (91.7%) aneurysms, only flow-diverting devices were deployed, and in the rest 12 (8.3%) of aneurysms, coils were used to loosely pack the aneurysm after deployment of a flow-diverting device. Five patients (4.5%) experienced ischemic complications, but no hemorrhagic complications were occurred. All patients had clinical follow-up 6-18 (median 12) after the procedure, with the modified Rankin scale score (mRS) 0 in 101 patients, 1 in four patients, 2 in three patients, 4 in one patient, and 5 in one patient. Digital subtraction angiography was performed at follow-up in 90 (81.8%) patients with 118 (81.4%) aneurysms 6-18 months (median 12) after the procedure, with the Raymond grade I in 90 (76.2%) aneurysms and Raymond grade III in 28 (23.7%). Eighteen patients with 22 partially occluded aneurysms at the first angiographic follow-up experienced the second digital subtraction angiography 12-36 months (median 26) after the procedure, and 21 (95.5%) aneurysms were completely occluded. Two patients had asymptomatic in-stent stenosis.

Conclusion

Treatment of small unruptured intracranial aneurysms with flow diverters can be performed safely and effectively with satisfactory outcomes.

[Detection rate and clinical significance of regions of homozygosity in prenatal genetic diagnosis]

Objective: To detect the incidence and analyze the clinical significance of regions of homozygosity (ROH) through the single nucleotide polymorphism array (SNP array). Methods: The SNP array detection results of 5 116 pregnant women in the Third Affiliated Hospital of Guangzhou Medical University from January 2016 to December 2020 were retrospectively analyzed. The pregnant women with ROH (5 Mb as the threshold) were followed up to analyze the relationship between ROH and abnormal fetal phenotype. Whole exon sequencing was performed in 4 cases of consanguineous marriage to detect potential recessive causative genes in the ROH region. Results: (1) A total of 39 cases of ROH were detected, with a positive rate of 0.76% (39/5 116). Among them, 25 cases (64%, 25/39) were detected only on single chromosome, and chromosome 11 had the highest detection rate, suggesting the risk of uniparental disomy; fourteen cases (36%,14/39) were detected on multiple chromosomes, most commonly on chromosomes 11, 1, 3, 4 and 8. (2) The number of cases and detection rate of ROH detected by different prenatal diagnosis indicators were as follows: 12 cases (1.78%, 12/676) in pregnant women with abnormal non-invasive prenatal testing result, 12 cases (0.37%, 12/3 284) in pregnant women with ultrasound abnormality, 4 cases (4/4) in pregnant women with consanguineous marriage, 3 cases (0.92%, 3/326) in pregnant women with previous adverse pregnancy, 2 cases (1.15%, 2/174) in pregnant women with high risk of serology in screening, 2 cases (4.00%, 2/50) in pregnant women with abnormal fetal chromosomal karyotype, 2 cases (0.79%, 2/253) in pregnant women with advanced maternal age, 1 case (0.56%, 1/178) in pregnant women with related parental genetic factors and 1 case (0.58%, 1/171) in pregnant women with the other factors. (3) The follow-up results of 39 cases of prenatal ROH showed that there were 16 cases of term birth, 15 cases of termination of pregnancy, 2 cases of preterm births, 1 case of fetal death and 5 cases lost to follow-up. Conclusions: Chromosomal ROH phenomenon is not rare. By analyzing the detection rate of ROH in prenatal diagnosis, combined with the results of fetal phenotype and postpartum follow-up, the clinical characteristics of ROH are discussed, so as to better understand the relationship between ROH and its phenotype.

Endovascular Management of Intracranial Atherosclerosis-Related Large Vessel Occlusion With the A Direct Aspiration First-Pass Thrombectomy Compared With Solumbra Technique

Background: To investigate the effect of the A Direct Aspiration First-Pass Thrombectomy (ADAPT) vs. Solumbra technique in the treatment of acute intracranial atherosclerosis-related large vessel occlusion (LVO).

Methods: Patients with acute atherosclerosis-related LVO who had undergone endovascular treatment were retrospectively enrolled into two groups: The Solumbra and ADAPT groups. The clinical data were analyzed.

Results: Patients (104) were enrolled with 48 in the Solumbra and 56 in the ADAPT group. The mean time from femoral access to recanalization was significantly (P < 0.05) shorter in the ADAPT than in the Solumbra group. The recanalization time at the first line was significantly shorter in the ADAPT group than in the Solumbra group (17 ± 10.21 vs. 26 ± 15.55 min, P = 0.02). However, the rate of switching to the alternative was significantly higher in the ADAPT group than that in the Solumbra group (46.42 vs. 33.33%, P = 0.01). Eighty-two patients had eventual recanalization, resulting in a final recanalization rate of 78.85%. At 3-month clinical follow-up for all patients, the good prognosis rate reached 51.92% with good prognosis in 24 patients (50%) in the Solumbra and 30 (53.57%) in the ADAPT group. The rate of symptomatic intracranial hemorrhage was 18.75% (n = 9) in the Solumbra and 19.64% (n = 11) in the ADAPT group. The mortality rate was 21.15% (22/104). Among 80 (76.92%) patients who had angiographic follow-up (3–30 months), five (6.25%) patients experienced in-stent stenosis, and two (2.5%) experienced asymptomatic stent occlusion.

Conclusion: In patients with acute intracranial atherosclerosis-related LVO, clinical outcomes treated using the ADAPT technique are comparable with those using the Solumbra technique, and more patients need additional remedial measures if treated with the ADAPT technique.

Application of retrievable Solitaire AB stents in the endovascular treatment of acute ischemic stroke

Purpose: Retrievable stents are widely used in acute ischemic stroke (AIS); however, the results remain unclear in Chinese patients. This study aimed to explore the usefulness of Solitaire AB stents in AIS. Materials and Methods: Seventy-three AIS patients treated with Solitaire AB stents for thrombectomy of large artery occlusion of anterior circulation in January 2014-June 2015 were retrospectively evaluated. Recanalization was assessed with the Thrombolysis In Cerebral Ischemia (TICI) scale. Clinical outcomes were assessed according to the National Institute of Health Stroke Scale (NIHSS) and the modified Rankin Scale (mRS). Operation-related complications were recorded. The main factors affecting successful recanalization with Solitaire AB were analyzed. Results: The 73 patients enrolled included 39 males and 34 females (median age of 59 [31-78] years); 77 Solitaire AB stents were used. The initial recanalization rate with Solitaire AB as the first thrombectomy method was 53.42% (39/73; recanalization group). Among the 34 patients with failed stent retrieval, 32 underwent other treatments; the final arterial recanalization rate was 89.04% (65/73). Perioperative embolization events and symptomatic intracranial hemorrhage (sICH) occurred in 5 and 8 patients, respectively. The mean NIHSS score was 9.12±3.86 one week after thrombectomy, significantly lower compared with admission values. In 31 patients (42.47%), NIHSS score decreased by >8. Good functional independence (mRS score≤2) was achieved in 39 patients (53.42%) at 90 days; 12 patients (16.44%) died. Compared with the recanalization group, the remaining patients showed lower AF and higher LAA percentages. Conclusion: Solitaire AB stents are useful in the endovascular treatment of AIS.

[Clinical applications of intelligent pressure control flexible ureteroscope for the treatment of renal calculi ≤2 cm]

Objective: To evaluate the effectiveness and safety of intelligent pressure control flexible ureteroscope for management of renal stones ≤2 cm. Methods: The clinical data of 267 cases of renal calculi treated with flexible ureteroscope lithotripsy at Department of Urology, Ganzhou People's Hospital from June 2015 to December 2017 were analyzed retrospectively. There were 129 male and 138 female patients, with a mean age of 51.2 years (ranging from 19 to 76 years). Among them, 145 patients underwent intelligent pressure control flexible ureteroscope (intelligent control group) and 122 patients underwent flexible ureteroscope ordinary (ordinary group). The t test, χ² test or Fisher exact test were used for statistical analysis. The success rate of stone seeking, the stone free rates, the incidence of complications, the average operation time, the average hospital stay after operation were compared between the two groups. Results: The average mean operative time of the patients with intelligent control group was (26.17 ± 8.64) minutes, significantly shorter than (47.23±18.35) minutes of the ordinary group (t=1.968, P=0.000). The stone free rate of the patients with intelligent control group was 97.2%, it was higher than 86.0% of ordinary group (χ²=0.069, P=0.004). The complication rate of the patients with intelligent control group was 2.7%, which was significantly shorter than 18.0% of the ordinary group (χ²=17.586, P=0.000). However, there was no significant difference between the two groups in the success rate of stone seeking and postoperative hospital stay (P>0.05). Conclusion: Intelligent controlled pressure ureteral flexible ureteroscope has the advantages of short operation time, high stone free rate and less complications in the treatment of renal calculi ≤2 cm compared with flexible ureteroscope ordinary.

Characteristics and Endovascular Management of the Posterior Cerebral Artery Anterior Temporal Branch Aneurysms

PURPOSE

To investigate characteristics of the posterior cerebral artery anterior temporal branch aneurysm and the safety and efficacy of endovascular management.

MATERIALS AND METHODS

A total of 6 patients with anterior temporal branch aneurysms were enrolled. All 6 patients had concurrent occlusion of the ipsilateral anterior circulating arteries. The aneurysms ranged from 2.5 to 5.0 mm. All patients were treated and followed up.

RESULTS

Four unruptured aneurysms were treated with coil embolization of the aneurysm sac only, with the parent artery maintained in 2 patients, slow flow in the parent artery in one and thrombosis at the aneurysm neck leading to parent artery occlusion in the last one. One patient with subarachnoid hemorrhage was treated with coil embolization of both the aneurysm and the parent artery, and the last patient with subarachnoid hemorrhage was treated with the Glubran 2 glue to embolize both the aneurysm and the parent artery. One patient with subarachnoid hemorrhage died of lung complication after embolization. Followed up for 3 months to 1 year, the 4 patients with unruptured aneurysms had no symptoms, including 1 patient with slow flow in the anterior temporal artery and 1 patient with thrombosis and parent artery occlusion. The remaining patient with parent artery occlusion had a good recovery.

CONCLUSIONS

The anterior temporal artery aneurysm is a special subtype of aneurysm and can be readily misdiagnosed as on the posterior cerebral artery trunk or the superior cerebellar artery. Endovascular management has a greater success rate, good effect, and fewer complications but with greater difficulties.

Severe symptomatic intracranial internal carotid artery stenosis treated with intracranial stenting: a single center study with 58 patients

PURPOSE

We aimed to investigate the safety and effectiveness of intracranial stenting in a population with severe (≥ 70%) symptomatic intracranial internal carotid artery (ICA) atherosclerotic stenosis.

METHODS

Fifty-eight patients with severe intracranial ICA atherosclerotic stenosis were prospectively enrolled. The baseline data, cerebral angiography, success rate, perioperative complications, clinical and imaging follow-up were prospectively analyzed.

RESULTS

All patients had successful intracranial stenting (100%), and the mean degree of stenosis was improved from 84.3% ± 7.5% to 23.5% ± 5.1% after the stent procedure. During the 30-day perioperative period, only one patient (1.7%) had ischemic stroke. Seven patients (12.1%) had headache and dysphoria. Thirty-six patients (62.1%) had clinical follow-up for 6-68 months after stenting. Five female patients (13.9%) had ipsilateral stroke including one death, but no disabling stroke, while three other patients (8.3%) had ipsilateral temporary ischemic attack (TIA). The recurrent stroke rate was higher in patients presenting with stroke (4/17, 23.5%) than in patients presenting with TIA (1/19, 5.3%), with no statistical significance (P = 0.33). Thirteen patients (22.4%) had imaging follow-up of 5-12 months following stenting, five of whom (38.5%) had in-stent restenosis.

CONCLUSION

Intracranial stenting for patients with intracranial ICA atherosclerotic stenosis has a low perioperative stroke rate and decent outcome on long-term follow-up, despite a relatively high in-stent restenosis rate.

Wingspan stenting can effectively prevent long-term strokes for patients with severe symptomatic atherosclerotic basilar stenosis

OBJECTIVE

To investigate the safety and long-term effect of using the Wingspan stent for severe symptomatic atherosclerotic basilar artery stenosis (≥70%).

MATERIALS AND METHODS

Between July 2007 and April 2013, we had 91 consecutive patients (age range 41-82 years old) with symptomatic severe basilar stenosis (70-99%) who underwent Wingspan stenting at our center. All patients had stenosis-related temporary ischemic attack or strokes. We analyzed the demographic data, pre- and post-procedural cerebral angiography, technical success rate, peri-procedural complications, and clinical and imaging follow-ups.

RESULTS

The Wingspan stenting procedure was successful in all patients: The stenosis was reduced from 82.2% ± 5.8% pre-stenting to 15.9% ± 5.7% post-stenting. The 30-day peri-operative rate for stroke or death was 14.3%, which included ischemic stroke in 12 cases (12/91 = 13.2%) and subarachnoid hemorrhage in one case (1/91 = 1.1%), with a fatal or disabling stroke rate of 2.2%. Among the 77 patients with clinical follow-up assessment within 7-60 months (mean 31.3 ± 15.1 months) after stenting, four patients (5.2%) had posterior ischemia, including one patient with disabling ischemic stroke (1.3%) and three patients (3.9%) with temporary ischemic attack. The 2-year cumulative stroke rate was 16% (95% CI: 8.2-23.8%). Among 46 patients with imaging assessments at 3-45 months (mean, 9.5 ± 8.3) post-stenting, six (13.0%) patients had restenosis, including two (2/46 = 4.3%) with symptomatic restenosis.

CONCLUSIONS

The benefit of stenting for patients with severe basilar artery stenosis (> 70%) may lie in lowering the long-term fatal and disabling stroke rate; and as long as the peri-operative stroke rate can be kept at a relatively lower level, patients with severe basilar stenosis can benefit from basilar artery stenting.

Outcomes of middle cerebral artery angioplasty and stenting with Wingspan at a high-volume center

INTRODUCTION

This study was to investigate the periprocedural stroke rates, safety, and long-term effect of Wingspan stenting for symptomatic severe stenosis of the middle cerebral artery (MCA) at a high-volume center.

METHODS

Between July 2007 and April 2013, 196 consecutive patients with severe MCA atherosclerotic stenosis (≥70%) who were treated with Wingspan stenting were retrospectively studied. All patients had arterial stenosis-related temporary ischemic attack or strokes. The demographic data, cerebral angiography, technical success rate, periprocedural complications, and clinical and imaging follow-up were analyzed.

RESULTS

The successful stenting rate was 98.0%, and the stenosis rate was improved from pre-stenting (80.6 ± 8.3 %) to post-stenting (15.5 ± 6.8%). The 30-day periprocedural stroke or death rate was 7.1%, with a disabling or fatal rate of 2.6%. The perioprocedural stroke rate was significantly (P < 0.01) greater in the early learning stage (16.0%) than in the later technical maturation stage (4.1%). The total periprocedural ischemic and perforator stroke rates were greater in patients with the most stenosis in the distal MCA 1/3 segment (6.8 and 5.7%, respectively) than in the proximal and middle 2/3 segments (0.9 and 0%, respectively). The ipsilateral stroke or death rate beyond 30 days (6-69 months, mean 30 ± 16) was 4.8%, with the 1- and 2-year cumulative stroke rates of 9.6 and 12.1%, respectively. Imaging follow-up 6-69 months (mean 10.9 ± 8.5) revealed restenosis in 21 cases (20.4 %).

CONCLUSION

Intracranial stenting of MCA stenoses may have the potential of better clinical outcomes if patients are properly selected and treated by an experienced operator at a high-volume center.

Wingspan Stenting for Severe Symptomatic Intracranial Atherosclerotic Stenosis in 433 Patients Treated at a Single Medical Center

Purpose

To investigate the safety and outcome of intracranial stenting for intracranial atherosclerotic stenosis (IAS).

Materials and Methods

Between July 2007 and April 2013, 433 consecutive patients with IAS >70% underwent intracranial Wingspan stenting, and the data were prospectively analyzed.

Results

Intracranial stenting was successful in 429 patients (99.1%), and the mean stenosis rate was improved from prestenting (82.3± 7.6)% to poststenting (16.6 ± 6.6)%. During the 30-day perioperative period, 29 patients (6.7%) developed stroke. The total perioperative stroke rate was significantly (P <0.01) higher in the basilar artery area than in others, whereas the hemorrhagic stroke rate was significantly (P <0.05) greater in the middle cerebral artery area than in others. The experience accumulation stage (13%) had a significantly (P <0.05) higher stroke rate than the technical maturation stage (4.8%). Clinical follow-up 6–69 months poststenting revealed ipsilateral stroke in 20 patients (5.5%). The one- and two-year cumulative stroke rates were 9.5% and 11.5%, respectively; the two-year cumulative stroke rate was significantly (P <0.05) greater in the experience accumulation stage (18.8%) than in the technical maturation stage (9.1%).

Conclusion

Wingspan stenting for intracranial atherosclerotic stenosis is safe and the long-term stroke rate after stenting is low in a Chinese subpopulation.

Symptomatic intracranial vertebral artery atherosclerotic stenosis (≥70%) with concurrent contralateral vertebral atherosclerotic diseases in 88 patients treated with the intracranial stenting

PURPOSE

To investigate the safety, effect and instent restenosis rate of Wingspan stenting in treating patients with intracranial vertebral artery atherosclerotic stenosis (70-99%) concurrent with contralateral vertebral artery atherosclerotic diseases.

MATERIALS AND METHODS

Eighty-eight patients with severe symptomatic intracranial vertebral artery atherosclerotic stenosis (≥70%) combined with contralateral vertebral artery atherosclerotic diseases were treated with the Wingpsan stent. All the baseline, cerebral angiography, success rate, perioperative complications, clinical and imaging follow-up data were prospectively analyzed.

RESULTS

The success rate of stenting was 100%, and the mean stenotic rate was reduced from prestenting (84.9±6.8)% to poststenting (17.2±5.9)%. The perioperative stroke rate was 1.1%. Among eighty patients (90.9%) with clinical follow-up 8-62 months (mean 29.3±17.2) poststenting, five (6.3%) had posterior circulation TIA only, three (3.8%) had mild stroke in the posterior circulation but recovered completely, and another five patients greater than 70 years old died of non-ischemic stroke. Imaging follow-up in 46 patients (52.3%) 5-54 months (mean 9.9±9.9) following stenting revealed instent restenosis in 12 patients (26.1%) including 7 (58.3%) symptomatic restenosis. Age and residual stenosis were the two factors to significantly (P<0.05) affect instent restenosis.

CONCLUSION

Wingspan stenting in the intracranial vertebral artery atherosclerotic stenosis combined with contralateral vertebral artery atherosclerotic diseases has a low perioperative stroke rate and a good preventive effect on long-term ischemic stroke, but the instent restenosis rate is a little high.

The biological characteristics of dendritic cells derived in vitro from myelogeneous leukemia cells and healthy donor cells

Successful adoptive immunotherapy for leukemia depends on the generation of T cells that can specifically react with malignant cells. Dendritic cells (DCs) are important antigen-presenting cells in the development of antileukemia T-cell responses. Mononuclear cells (MNC) were isolated from peripheral blood or bone marrow of patients with chronic myelogenous leukemia (CML), and acute myelogenous leukemia (AML). After incubation with granulocyte-macrophage colony-stimulating factor, interleukin (IL)-4, and tumor necrosis factor-alpha, MNC developed morphological characteristics of DCs in vitro, which were confirmed by phenotypic assay. Fluorescence in situ hybridization demonstrated the presence of fusion gene in the nuclei of representative CML or AML-M3 samples, indicating that the cells were leukemic in origin. IL-12 levels were significantly higher in AML-DCs and CML-DCs prestimulated with phorbol 12-myristate 13-acetate than in the corresponding leukemic cells, but were lower than that of healthy donors. These cells were potent stimulators of lymphocyte proliferation in specific in vitro assays for DC function. However, the stimulatory abilities of allogeneic T cells in a mixed lymphocyte reaction were impaired compared with those of mature DCs derived from healthy donors, although T-cell stimulatory effects were significantly increased in these differentiated leukemia-DCs. These results suggest that functional DCs may be derived from leukemic (AML, CML) blasts in a significant number of patients and may be capable of inducing leukemia-specific immune responses with potentially clinically beneficial effects.

Macrophage activation by polysaccharide biological response modifier isolated from Aloe vera L. var. chinensis (Haw.) Berg

A mannose-rich polysaccharide biological response modifier (BRM), derived from Aloe vera L. var. chinensis (Haw.) Berg., was demonstrated to be a potent murine B- and T-cell stimulator in our previous study. We here report the stimulatory activity of PAC-I on murine peritoneal macrophage. The polysaccharide when injected into mice enhanced the migration of macrophages to the peritoneal cavity. Peritoneal macrophage when treated by PAC-I in vitro had increased expression of MHC-II and FcgammaR, and enhanced endocytosis, phagocytosis, nitric oxide production, TNF-alpha secretion and tumor cell cytotoxicity. The administration of PAC-I into allogeneic ICR mice stimulated systemic TNF-alpha production in a dose-dependent manner and prolonged the survival of tumor-bearing mice. PAC-I is thus a potent stimulator of murine macrophage and the in vitro observed tumoricidal properties of activated macrophage might account for the in vivo antitumor properties of PAC-I. Our research findings may have therapeutic implications in tumor immunotherapy.

Combination therapy with anti-ICOS and cyclosporine enhances cardiac but not islet allograft survival

The blockade of costimulatory signals is a powerful strategy to prevent allograft rejection and facilitate transplantation tolerance. In recent years, a series of novel costimulatory molecules have been identified, including an inducible costimulatory molecule (ICOS). To date, little has been uncovered regarding the therapeutic potential of blocking ICOS signaling in the setting of transplantation. In a fully MHC-mismatched mouse model, we studied the effect of blocking ICOS signaling using a specific monoclonal antibody (anti-ICOS mAb) in combination with cyclosporine on cardiac and islet allograft survival. We demonstrated that combined treatment with anti-ICOS mAb and cyclosporine can induce long-term graft acceptance in cardiac but not islet allografts, suggesting that the type of transplanted tissue significantly influences the immunologic patterns of graft acceptance or rejection in this model.

Chemical and biological characterization of a polysaccharide biological response modifier from Aloe vera L. var. chinensis (Haw.) Berg

Three purified polysaccharide fractions designated as PAC-I, PAC-II, and PAC-III were prepared from Aloe vera L. var. chinensis (Haw.) Berg. by membrane fractionation and gel filtration HPLC. The polysaccharide fractions had molecular weights of 10,000 kDa, 1300 kDa, and 470 kDa, respectively. The major sugar residue in the polysaccharide fractions is mannose, which was found to be 91.5% in PAC-I, 87.9% in PAC-II, and 53.7% in PAC-III. The protein contents in the polysaccharide fractions was undetectable. NMR study of PAC-I and PAC-II demonstrated the polysaccharides shared the same structure. The main skeletons of PAC-I and PAC-II are beta-(1-->4)-D linked mannose with acetylation at C-6 of manopyranosyl. The polysaccharide fractions stimulated peritoneal macrophages, splenic T and B cell proliferation, and activated these cells to secrete TNF-alpha, IL-1 beta, INF-gamma, IL-2, and IL-6. The polysaccharides were nontoxic and exhibited potent indirect antitumor response in murine model. PAC-I, which had the highest mannose content and molecular weight, was found to be the most potent biological response modifier of the three fractions. Our results suggested that the potency of aloe polysaccharide fraction increases as mannose content and molecular weight of the polysaccharide fraction increase.

The role of the class II transactivator (CIITA) in MHC class I and II regulation and graft rejection in kidney

Class II transactivator (CIITA) induces transcription of MHC class II genes, and induces class I in some cell lines. We examined the effect of CIITA deficiency on class I and II expression in mouse kidney. In CIITA knockout (CIITAKO) mice, basal class II was absent, but class I levels were mildly but significantly increased. Allogeneic stimulation or ischemic injury increased class I and II expression in kidneys of control (wild-type, WT) mice but induced only class I in CIITAKO mice. Thus, in kidney, all basal and induced class II expression was CIITA-dependent, but neither basal nor induced class I was CIITA-dependent. Rejecting kidney allografts from CIITAKO mice in CBA hosts manifested intense induction of donor class I but no donor class II expression. Rejecting kidneys from both WT and CIITAKO donors showed predominantly CD8 T-cell infiltration at days 7 and 21, with increasing tubulitis and arteritis at day 21. CIITAKO kidneys showed fewer infiltrating cells than WT kidneys at day 21. Thus CIITA-deficient kidneys have no basal and induced class II expression but display intense induction of class I expression, and evoke typical rejection lesions, although some indices of infiltration are reduced at day 21.

IFN-gamma alters the pathology of graft rejection: protection from early necrosis

We studied the effect of host IFN-gamma on the pathology of acute rejection of vascularized mouse heart and kidney allografts. Organs from CBA donors (H-2k) were transplanted into BALB/c (H-2d) hosts with wild-type (WT) or disrupted (GKO, BALB/c mice with disrupted IFN-gamma genes) IFN-gamma genes. In WT hosts, rejecting hearts and kidneys showed mononuclear cell infiltration, intense induction of donor MHC products, but little parenchymal necrosis at day 7. Rejecting allografts in GKO recipients showed infiltrate but little or no induction of donor MHC and developed extensive necrosis despite patent large vessels. The necrosis was immunologically mediated, since it developed during rejection, was absent in isografts, and was prevented by immunosuppressing the recipient with cyclosporine or mycophenolate mofetil. Rejecting kidneys in GKO hosts showed increased mRNA for heme oxygenase 1, and decreased mRNA for NO synthase 2 and monokine inducible by IFN-gamma (MIG). The mRNA levels for CTL genes (perforin, granzyme B, and Fas ligand) were similar in rejecting kidneys in WT and GKO hosts, and the host Ab responses were similar. The administration of recombinant IFN-gamma to GKO hosts reduced but did not fully prevent the effects of IFN-gamma deficiency: MHC was induced, but the prevention of necrosis and induction of MIG were incomplete compared with WT hosts. Thus, IFN-gamma has unique effects in vascularized allografts, including induction of MHC and MIG, and protection against parenchymal necrosis, probably at the level of the microcirculation. This is probably a local action of IFN-gamma produced in large quantities in the allograft.

Interferon-gamma acts directly on rejecting renal allografts to prevent graft necrosis

In transplant rejection interferon (IFN)-gamma regulates the recipient immune response but also acts directly on IFN-gamma receptors in the graft. We investigated these direct actions by comparing rejecting kidneys from donors lacking IFN-gamma receptors (GRKO mice) or control donors (129Sv/J) in CBA recipients. Beginning day 5, 129Sv/J kidneys displayed high major histocompatibility complex (MHC) expression, progressive infiltration by inflammatory cells, but no thrombosis and little necrosis, even at day 21. GRKO kidneys showed increasing fibrin thrombi in small veins, peritubular capillary congestion, hyaline casts, and patchy parenchymal necrosis, progressing to near total necrosis at day 10. Terminal dUTP nick-end labeling assays were positive only in the interstitial infiltrate, confirming that massive cell death in GRKO transplants was not apoptotic. Paradoxically, GRKO kidneys showed little donor MHC induction and less inflammatory infiltration. Both GRKO and 129Sv/J allografts evoked vigorous host immune responses including alloantibody and mRNA for cytotoxic T cell genes (perforin, granzyme B, Fas ligand), and displayed similar expression of complement inhibitors (CD46, CD55, CD59). GRKO kidneys displayed less mRNA for inducible nitric oxide synthase and monokine inducible by IFN-gamma but increased heme oxygenase-1 mRNA. Thus IFN-gamma acting on IFN-gamma receptors in allografts promotes infiltration and MHC induction but prevents early thrombosis, congestion, and necrosis.

Interferon-gamma acts directly on rejecting renal allografts to prevent graft necrosis

In transplant rejection interferon (IFN)-gamma regulates the recipient immune response but also acts directly on IFN-gamma receptors in the graft. We investigated these direct actions by comparing rejecting kidneys from donors lacking IFN-gamma receptors (GRKO mice) or control donors (129Sv/J) in CBA recipients. Beginning day 5, 129Sv/J kidneys displayed high major histocompatibility complex (MHC) expression, progressive infiltration by inflammatory cells, but no thrombosis and little necrosis, even at day 21. GRKO kidneys showed increasing fibrin thrombi in small veins, peritubular capillary congestion, hyaline casts, and patchy parenchymal necrosis, progressing to near total necrosis at day 10. Terminal dUTP nick-end labeling assays were positive only in the interstitial infiltrate, confirming that massive cell death in GRKO transplants was not apoptotic. Paradoxically, GRKO kidneys showed little donor MHC induction and less inflammatory infiltration. Both GRKO and 129Sv/J allografts evoked vigorous host immune responses including alloantibody and mRNA for cytotoxic T cell genes (perforin, granzyme B, Fas ligand), and displayed similar expression of complement inhibitors (CD46, CD55, CD59). GRKO kidneys displayed less mRNA for inducible nitric oxide synthase and monokine inducible by IFN-gamma but increased heme oxygenase-1 mRNA. Thus IFN-gamma acting on IFN-gamma receptors in allografts promotes infiltration and MHC induction but prevents early thrombosis, congestion, and necrosis.

[Comparative studies on gene expression of isozymes in 4 types of various ploidy crucian carp during embryogenesis]

Isozyme zymograms of esterase (EST), lactate dehydrogenase (LDH), malate dehydrogenase (MDH) and superoxide dismutase (SOD) were analysed by polyacrylamide gradient gel electrophoresis at different developmental stages of embryogenesis in 4 types of various ploidy crucian carp embryos, including haploids, diploids, natural triploids, and multiple tetraploids, and 2 types of haploid and diploid common carp embryos. Haploid embryos of crucian carp (Carassius auratus) and common carp (Cyprinus carpio) were produced by treating eggs with UV-irradiated milt from blunt snout bream (Megalobrama amblycephala). Natural triploid embryos were obtained from the eggs of gynogenetic silver crucian carp (Carassius auratus gibelio) inseminated with milt from red common carp. Multiple tetraploid embryos were also produced by gynogenesis from eggs of the newly discovered multiple tetraploid females inseminated with milt from red common carp. Gradient gel electrophoresis indicated that the band types and staining intensity of 4 isozymes expressed in haploid embryos of crucian carp and red common carp were similar to that in the correlative diploid embryos. In natural triploid silver crucian carp embryos, the zymograms of MDH and SOD isozymes were identical with that of diploid crucian carp embryos, but the EST and LDH isozymes manifested more new enzyme bands in comparison with diploid embryos. The corresponding expressed products of some bands in the triploid embryos, such as EST5 and EST6, could be observed also in red common carp embryos, which provided evidence for hybrid origin about the gynogenetic fish. The multiple tetraploids incorporated one foreign genome of red common carp, therefore, the effects of genes from the foreign genome could be observed in the multiple tetraploid embryos. Gene expression of the isozymes in the tetraploid embryos was somewhat similar to that in hybrids. Owing to interaction of triploid silver crucian carp genomes and common carp haploid genome, some isozyme bands, such as EST5 and EST6, changed in quantity, and some bands increased, such as s-SOD1, s-SOD2, s-SOD3 and s-SOD4 in the tetraploid embryos. Moreover, the heterogeneity was revealed among embryos developed from gynogenetic eggs of 3 different multiple tetraploid individuals.

Antioxidant flavonoid glycosides from Daphniphyllum calycinum

A novel flavonoid diglycoside, 5,6,7,4'-tetrahydroxyflavonol 3-O-rutinoside (1), and a previously known compound, kaempferol 3-O-neohesperidoside (2), were isolated from an ethyl acetate extract of Daphniphyllum calycinum leaves that showed significant activity in a 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical assay. The structure of 1 was elucidated by a combination of spectroscopic methods, and compounds 1 and 2 were found to be moderately active as antioxidants in the DPPH assay.

Liver transplantation induces cytochrome P450 1A1 dependent monooxygenase activity in rat lung and kidney

Although liver transplantation has been the subject of intensive investigation, comparatively little is known regarding the effects of this procedure on the metabolism of xenobiotics. The objective of the present study was to examine the effect of orthotopic liver transplantation on rat hepatic, pulmonary, and renal microsomal cytochrome P450 (P450) monooxygenase activity through the use of isozyme-selective substrates. Pulmonary microsomal P450 1A1 dependent 7-ethoxyresorufin O-deethylation (ERFD) activity increased over time in recipient rats, with maximal induction (750% of donor) observed after 21 days. Similarly, ERFD activity in renal microsomes was increased (200% of donor) after 21 days. Both pulmonary and renal microsomal P450 2B dependent 7-pentoxyresorufin O-depentylation (PRFD) activity was decreased (50 and 75% of donor) 1 day after transplantation but was essentially unchanged 3, 7, and 21 days after transplantation. Pulmonary and renal microsomal heme oxygenase activities were not significantly affected by liver transplantation. In contrast, total hepatic microsomal P450 concentrations were decreased maximally (to 45% of donor concentration) 7 days after transplantation and remained low (55% of donor) up to 21 days. Similarly, hepatic P450 1A dependent ERFD and P450 2B dependent PRFD activities were maximally depressed (20 and 25% of donor activities) after 7 days and remained low (75 and 30% of donor) up to 21 days after transplantation. The decreases in rates of hepatic P450 monooxygenation were accompanied by significant increases in microsomal heme oxygenase activity. The data presented in this study suggest the existence of generalized stress responses to inflammation that result in tissue- and isozyme-selective modulation of P450 monooxygenase activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Nephrotoxicity in rats following liver transplantation from cadmium-exposed rats

Although kidney is considered as the critical organ for cadmium (Cd) toxicity, little is known about the transport of Cd to kidney after chronic exposure. In order to study this transfer, male Lewis rats (150-200 g) were given eight injections (sc) of CdCl2 (3 mg Cd/kg) over 2 weeks which resulted in increases of tissue Cd and metallothionein (MT) concentrations (223 and 1850 micrograms/g, respectively, in the liver and 118 and 873 micrograms/g, respectively, in the kidney). Livers from Cd-injected rats were transplanted to age-matched control healthy Lewis rats and the recipient rats were killed at 2 to 47 days after transplantation. The levels of Cd and MT in the liver of recipient rats were decreased (106 and 1503 micrograms/g, respectively) with time after surgery. On the other hand, renal Cd and MT levels were markedly increased (195 and 1468 micrograms/g, respectively) and most of the Cd in the kidney was bound to MT. About 100 ng/ml of Cd and MT were detected in the plasma of recipient rats by ELISA. There was some periportal fibrosis in the liver due to transplant procedure which did not anastomose hepatic arteries. There was an increase in blood urea nitrogen levels in rats transplanted with Cd-containing liver. In addition, both necrosis and inflammation were observed in the epithelial cells in the proximal tubules in the kidney which typically occurs in chronic Cd toxicity. These results suggest that the major source of renal Cd in chronic Cd exposure may be derived from hepatic Cd which is transported in the form of Cd-MT in blood plasma.

Genotoxicity of heated cooking oil vapors

Epidemiological studies of lung cancer in Chinese women indicated that factors other than cigarette smoking are related to lung cancer risk. A case-control study suggested that indoor air pollution, particularly from cooking oil emissions, may be involved. Condensates of volatile emissions from rapeseed and soybean cooking oils were prepared and found to be genotoxic in short-term tests including the Salmonella mutation assay, SV50 forward-mutation assay, and sister-chromatid exchange assay, as well as the micronucleus assay in mouse bone marrow. In contrast, condensates from rapeseed oil with butylated hydroxyanisole or hydrogenated rapeseed oil were not mutagenic, implicating oxidation products as the cause for mutagenicity. Peanut oil and lard condensates were not mutagenic in any assay. The association of exposure to Chinese rapeseed cooking-oil emissions and lung-cancer risk may be related to the mutagenic component of these condensates.