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Objective:To investigate the effect of magnetic resonance angiography (MRA) in evaluating the mouse model of vertebrobasilar dolichoectasia (VBD) induced by injection of elastase into cerebellomedullary cistern.Methods:Twenty-four male C57/BL6 mice were selected. The mice in the elastase group ( n=12) were injected in the cerebellomedullary cistern with 2.5 μl of phosphate buffer containing 25 mU elastase, and the mice in the saline control group ( n=12) were injected with the same volume of normal saline. MRA examination of the brains of living mice was performed 2 weeks after modeling. Successful modeling was defined as the basilar artery bending angle ≤170°, or the basilar artery bending length accounts for ≥10%, or the basilar artery deviated from the midline by more than 1 grade, or the percentage increase in artery diameter was ≥25%. Results:In the elastase group and the saline control group, 2 mice and 1 mouse did not wake up normally or died, respectively. The 11 surviving mice in the saline control group had no obvious vertebral artery and basilar artery abnormalities. The success rate of modeling in the 10 surviving mice in the elastase group was 80%, and the difference in the success rate between the two groups was statistically significant ( P<0.05). There were significant differences in mean basilar artery diameter (0.30 mm vs. 0.22 mm; P<0.05), mean basilar artery bending angle (115° vs. 170°; P<0.05), and proportion of mean basilar artery bending length (31% vs. 5%; P<0.05) of the surviving mice between the elastase group and the saline control group. Conclusion:MRA can better evaluate the mouse VBD model induced by elastase injection in the cerebellomedullary cistern.
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Intracranial arterial dolichoectasia (IADE), also known as dilatative arteriopathy of the brain vessels, refers to an increase in the length and diameter of at least one intracranial artery, and accounts for approximately 12% of all patients with stroke. However, the association of IADE with stroke is usually unclear. Cerebral small vessel disease (CSVD) is characterized by pathological changes in the small vessels. Clinically, patients with CSVD can be asymptomatic or present with stroke or cognitive decline. In the past 20 years, a series of studies have strongly promoted an understanding of the association between IADE and CSVD from clinical and pathological perspectives. It has been proposed that IADE and CSVD may be attributed to abnormal vascular remodeling driven by an abnormal matrix metalloproteinase/tissue inhibitor of metalloproteinase pathway. Also, IADErelated hemodynamic changes may result in initiation or progression of CSVD. Additionally, genetic factors are implicated in the pathogenesis of IADE and CSVD. Patients with Fabry’s disease and late-onset Pompe’s disease are prone to developing concomitant IADE and CSVD, and patients with collagen IV alpha 1 or 2 gene (COL4A1/COL4A2) and forkhead box C1 (FOXC1) variants present with IADE and CSVD. Race, strain, familial status, and vascular risk factors may be involved in the pathogenesis of IADE and CSVD. As well, experiments in mice have pointed to genetic strain as a predisposing factor for IADE and CSVD. However, there have been few direct genetic studies aimed towards determining the association between IADE and CSVD. In the future, more clinical and basic research studies are needed to elucidate the causal relationship between IADE and CSVD and the related molecular and genetic mechanisms.
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Objective To explore the effects of vertebral artery hypoplasia (VAH)on falsenegative rates with MRI in isolated acute vestibular syndrome (AIVS) patients with small posterior circulation small infarcts (infarct diameter ≤ 10 mm by DWI).Methods A total of 224 AIVS patients with at least one stroke risk factor (defined as high-risk AIVS)were consecutively recruited.Head impulse,nystagmus and test-of-skew(HINTS),brainstem auditory evoked potential (BAEP),and blink reflex(BR)were performed as soon as possible ahead of MRI.Another MRI was carried out in those with negative findings on the first imaging but suspected of a central lesion based on HINTS + BAEP + BR.Patients were divided into a VAH group and a non-VAH group.Results Of the 98 cases with posterior circulation infarcts,37 cases were small infarcts,including 16 in the VAH group(16/61,26.2％)and 21 in the non VAH group(21/163,12.9％),with a significant difference between the groups(x2 =4.58,P ＜ 0.05).Nine VAH patients (9/16,56.3 ％)and 4 non-VAH patients(4/21,19.0％)presented false negative results on cranial MRI-DWI,and the difference was also statistically significant(x2 =6.23,P＜0.001).HINTS + BAEP + BR showed a higher sensitivity than early MRI in identifying small infarcts(VAH group:100.0％ vs.44.0％ or 7/16,U=6.41,P＜0.001;non-VAH group:100.0％ vs.81.0％ or 17/21,U=4.46,P＜0.0S).V wave peak latency,Ⅲ-Ⅴ and Ⅰ-Ⅴ wave interpeak latency,and the latency of R1,R2,and R2' in the VAH group were longer than in the non-VAH group(each P＜0.05).Conclusions When VAH is present in high-risk AIVS patients,small infarcts are common,with high false-negative rates on MRI-DWI.HINTS + BAEP + BR may help identify small infarcts and thus improve diagnostic sensitivity.
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Purpose To analyze the hemodynamic characteristics of brain stem in patients with basilar artery hypoplasia (BAH) by magnetic resonance perfusion-weighted imaging (PWI).Materials and Methods According to the inclusion and exclusion criteria,51 patients with BAH were selected as the BAH group,and 79 patients without BAH were selected as the non BAH group.All patients were examined by MRI,3D-TOF and PWI,and magnetic resonance angiography was acquired after the three examinations.The regional cerebral blood flow (rCBF),regional cerebral blood volume (rCBV),regional mean transit time (rMTT) and time to peak (TTP) values of pontine area were measured.Results The rCBF value of the BAH group [(17.10±6.52) ml/(100 g · min)] was significantly lower than that of the non BAH group [(29.06± 13.32) ml/(100 g · min)] (P＜0.05);the rCBV value of the BAH group [(1.41 ±0.26) ml] was significantly lower than that of the non BAH group [(2.62± 0.82) ml] (P＜0.05);the TTP value of the BAH group [(6.14± 1.31) s] was significantly higher than that of the non BAH group [(5.39 ± 1.08) s] (P＜0.05);the rMTT value of the BAH group [(20.78±3.48) s] was significantly higher than that of the non BAH group [(19.01 ±2.39) s] (P＜0.05).TTP was the most sensitive index of cerebral perfusion injury,and the incidence of TTP extension was 41.18％ in the BAH group.Conclusion PWI can detect the abnormal cerebral hemodynamics in patients with BAH,which provides the basis for the timely treatment and prevention of irreversible injury in the ischemic area of the brain.
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Vertebrobasilar dolichoectasia(VBD ) can increase the risk of stroke. Significant expansion, elongation and tortuosity of the vertebrobasilar arteries are the main morphology manifestations of VBD. However, there is no consensus on the quantitative imaging assessment of VBD. Many studies showed that some quantitative parameters, such as basilar artery length and bending length, basilar angulation, vertebral tortuosity index can be used for the quantitative imaging assessment of VBD.
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Objective To study the clinical characteristics and to summarize our experience in the diagnosis and treatment of ectopic splenic autotransplantation (ESAP) many years after splenic rupture and splenectomy.Methods The clinical data of 15 patients with ESAP who were treated in the People's Hospital of Zhengzhou from January 1998 to January 2013 were retrospectively analyzed.Results Of the 15 patients,2 patients presented with intestinal obstruction due to the ectopic splenic tissues and required partial resection of small intestine.In 5 patients,the ectopic splenic tissues were in the greater omentum which required resection of part or the whole of the greater omentum.In 4 patients,the ectopic splenic tissues were in the mesentery which required partial or total resection of the tissues.The ectopic tissues were in the pelvis in 3 patients and resection of the left fallopian tube was carried out in 2 patients and resection of the pelvic tissues in 1 patient.In 1 patient the diagnosis was made under laparoscopic biopsy,thus avoiding open surgery.Three patients had multiple implanted sites for these ectopic splenic tissues.Conclusions ESAP is an uncommon disease and it has no clinical characteristics.It is easy to confuse the condition with metastatic deposits.A diagnosis could be made only by combining the history with magnetic resonance imaging,or 99mTc study of red blood cells,or laparoscopic exploration and biopsy.
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<p><b>OBJECTIVE</b>To study whether As(2)O(3) has an apoptotic effect on human solid tumor cells, and the possible cellular and molecular mechanisms of this treatment using human esophageal squamous carcinoma cells (EC8712) as a model.</p><p><b>METHODS</b>DNA microarray, biochemical and cytological analyses were used.</p><p><b>RESULTS</b>The growth and survival of EC8712 cells were markedly inhibited by As(2)O(3) treatment at a concentration of 1, 2 and 4 micromol/L. EC8712 cells were obviously arrested at G2/M phase with As(2)O(3) treatment and apoptosis induced at micromolar As(2)O(3) concentrations, as shown by morphology, histogram related nuclear DNA contents, and DNA gel electrophoresis. As(2)O(3) activated caspase-3, which might be involved in the process of As(2)O(3), induced apoptosis in EC8712 cells.</p><p><b>CONCLUSIONS</b>As(2)O(3) changes the expression of many genes at transcription level. The regulation of expression of many genes might be involved in the process of As(2)O(3) inducing apoptosis. These results suggest that As(2)O(3) can be clinically useful for solid tumor treatment.</p>