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Wen-Han Hu, Chao Zhang, Kai Zhang, Fan-Gang Meng, Ning Chen and Jian-Guo Zhang

Object

Whether selective amygdalohippocampectomy (SelAH) has similar seizure outcomes and better neuropsychological outcomes compared with anterior temporal lobectomy (ATL) is a matter of debate. The aim of this study was to compare the 2 types of surgery with respect to seizure outcomes and changes in IQ scores.

Methods

PubMed, Embase, and the Cochrane Library were searched for relevant studies published between January 1990 and September 2012. Studies comparing SelAH and ATL with respect to seizure and intelligence outcomes were included. Two reviewers assessed the quality of the included studies and independently extracted the data. Odds ratios and standardized mean deviations with 95% confidence intervals were used to compare pooled proportions of freedom from seizures and changes in IQ scores between the SelAH and ATL groups.

Results

Three prospective and 10 retrospective studies were identified involving 745 and 766 patients who underwent SelAH and ATL, respectively. The meta-analysis demonstrated a statistically significant reduction in the odds of seizure freedom for patients who underwent SelAH compared with those who underwent ATL (OR 0.65 [95% CI 0.51–0.82], p = 0.0005). The differences between the changes in all IQ scores after the 2 types of surgery were not statistically significant, regardless of the side of resection.

Conclusions

Selective amygdalohippocampectomy statistically reduced the odds of being seizure free compared with ATL, but the clinical significance of this reduction needs to be further validated by well-designed randomized trials. Selective amygdalohippocampectomy did not have better outcomes than ATL with respect to intelligence.

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Liang-Hua Ma, Guang Li, Hong-Wei Zhang, Zhi-Yu Wang, Jun Dang, Shuo Zhang, Lei Yao and Xiao-Meng Zhang

Object

This study was undertaken to analyze outcomes in patients with newly diagnosed brain metastases from non–small cell lung cancer (NSCLC) who were treated with hypofractionated stereotactic radiotherapy (HSRT) with or without whole-brain radiotherapy (WBRT).

Methods

One hundred seventy-one patients comprised the study population. Fifty-four patients received HSRT alone, and 117 patients received both HSRT and WBRT. The median survival time (MST) was determined using the Kaplan-Meier method. Recursive Partitioning Analysis (RPA) and Graded Prognostic Assessment (GPA) were also used to evaluate the results. Univariate and multivariate analyses were performed to determine significant prognostic factors for overall survival. Tumor control, radiation toxicity, and cause of death in the HSRT and HSRT+WBRT groups were evaluated.

Results

The MST for all patients was 13 months. According to the Kaplan-Meier method, the probability of survival at 1, 2, and 3 years was 51.2%, 21.7%, and 10.1%. The MSTs for RPA Classes I, II, and III were 19, 12, and 5 months, respectively; and the MSTs for GPA Scores 4, 3, 2, and 1 were 24, 14, 12, and 6 months, respectively. The MSTs in the HSRT+WBRT and HSRT groups were 13 and 9 months (p = 0.044), respectively, for all patients, 13 and 8 months (p = 0.031), respectively, for patients with multiple brain metastases, and 16 and 15 months (p = 0.261), respectively, for patients with a single brain metastasis. The multivariate analysis showed that HSRT+WBRT was a significant factor only for patients with multiple brain metastases (p = 0.010). The Kaplan-Meier–estimated tumor control rates at 3, 6, 9, and 12 months were 92.2%, 82.7%, 79.5%, and 68.3% in the HSRT+WBRT group and 73.5%, 58.4%, 51.0%, and 43.3% in the HSRT group, respectively, in all 165 patients (p = 0.001). The estimated tumor control rates at 3, 6, 9, and 12 months were 94.3%, 81.9%, 79.6%, and 76.7%, respectively, in the HSRT+WBRT group and 77.8%, 61.4%, 52.6%, and 48.2%, respectively, in the HSRT group in the 80 patients harboring a single metastasis (p = 0.009). The estimated tumor control rates at 3, 6, 9, and 12 months were 90.5%, 83.5%, 79.5%, and 60.9%, respectively, in the HSRT+WBRT group and 68.2%, 54.5%, 48.5%, and 36.4%, respectively, in the HSRT group in the 85 patients with multiple metastases (p = 0.010). The toxicity incidences of Grade 3 or worse were 6.0% (7 of 117 patients) in the HSRT+WBRT group and 1.9% (1 of 54 patients) in the HSRT group (p = 0.438). The differences in neurological death rates between the HSRT+WBRT group and the HSRT group were not statistically significant (34.4% vs 44.7%, p = 0.125, in all patients; 30.0% vs 52.0%, p = 0.114, in patients with a single metastasis; and 38.0% vs 36.4%, p = 0.397, in patients with multiple metastases).

Conclusions

The overall survival results in the present study were similar to those in other studies. Hypofractionated stereotactic radiotherapy provides an alternative method to traditional stereotactic radiosurgery. We suggest that WBRT should be combined with HSRT in patients with single or multiple newly diagnosed brain metastases from NSCLC.

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Yanlu Zhang, Zheng Gang Zhang, Michael Chopp, Yuling Meng, Li Zhang, Asim Mahmood and Ye Xiong

OBJECTIVE

The authors' previous studies have suggested that thymosin beta 4 (Tβ4), a major actin-sequestering protein, improves functional recovery after neural injury. N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) is an active peptide fragment of Tβ4. Its effect as a treatment of traumatic brain injury (TBI) has not been investigated. Thus, this study was designed to determine whether AcSDKP treatment improves functional recovery in rats after TBI.

METHODS

Young adult male Wistar rats were randomly divided into the following groups: 1) sham group (no injury); 2) TBI + vehicle group (0.01 N acetic acid); and 3) TBI + AcSDKP (0.8 mg/kg/day). TBI was induced by controlled cortical impact over the left parietal cortex. AcSDKP or vehicle was administered subcutaneously starting 1 hour postinjury and continuously for 3 days using an osmotic minipump. Sensorimotor function and spatial learning were assessed using a modified Neurological Severity Score and Morris water maze tests, respectively. Some of the animals were euthanized 1 day after injury, and their brains were processed for measurement of fibrin accumulation and neuroinflammation signaling pathways. The remaining animals were euthanized 35 days after injury, and brain sections were processed for measurement of lesion volume, hippocampal cell loss, angiogenesis, neurogenesis, and dendritic spine remodeling.

RESULTS

Compared with vehicle treatment, AcSDKP treatment initiated 1 hour postinjury significantly improved sensorimotor functional recovery (Days 7–35, p < 0.05) and spatial learning (Days 33–35, p < 0.05), reduced cortical lesion volume, and hippocampal neuronal cell loss, reduced fibrin accumulation and activation of microglia/macrophages, enhanced angiogenesis and neurogenesis, and increased the number of dendritic spines in the injured brain (p < 0.05). AcSDKP treatment also significantly inhibited the transforming growth factor–β1/nuclear factor–κB signaling pathway.

CONCLUSIONS

AcSDKP treatment initiated 1 hour postinjury provides neuroprotection and neurorestoration after TBI, indicating that this small tetrapeptide has promising therapeutic potential for treatment of TBI. Further investigation of the optimal dose and therapeutic window of AcSDKP treatment for TBI and the associated underlying mechanisms is therefore warranted.

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Xinru Xiao, Zhen Wu, Liwei Zhang, Guijun Jia, Jie Tang, Guolu Meng and Junting Zhang

Object

In this paper the authors describe a modified far-lateral transcondylar approach to remove hypoglossal neurilemmomas (HGNs).

Methods

Between September 2008 and June 2011, 11 consecutive patients with HGNs underwent tumor removal via a modified far-lateral transcondylar approach. The average age at presentation, tumor characteristics, cranial nerve (CN) deficits, and outcomes were assessed. The modified far-lateral transcondylar approach comprises several important steps. The first step is to remove the limited posterior aspect of the condylar facet to open the hypoglossal canal. The second step is to expose the posterior arch and the transverse process of C-1. A fat layer covers the venous plexus of the vertebral artery, and careful dissection along this surface of the fat layer is important to protect the vertebral artery from damage. The neck muscles are dissected caudally to expose the extracranial component of the tumor, which is located in front of the transverse process of C-1.

Results

Eleven cases of HGNs were treated during the study period. The mean patient age was 47.4 ± 8.9 years (range 31–59 years); there were 3 men and 8 women. The mean follow-up period was 14.1 ± 9 months. All patients presented with hypoglossal nerve deficits; other commonly observed deficits included glossopharyngeal and vestibular/cochlear nerve deficits. Gross-total resection of the tumor was achieved in 10 patients. A subtotal resection of the tumor was achieved in the remaining patient. Two patients had transient postoperative facial nerve palsies, 1 patient developed a new CN XI palsy postoperatively, and 5 patients experienced transient hoarseness and difficulty swallowing. Two patients required a tracheotomy because they demonstrated dysfunction of the caudal CNs and subsequently developed postoperative pneumonia. Postoperatively, 5 patients required the temporary placement of a nasogastric feeding tube. There were no surgery-related deaths in this series.

Conclusions

The modified far-lateral transcondylar approach is an effective treatment for HGNs, yielding a high total tumor removal rate with an acceptable rate of morbidity.

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Ye Xiong, Yanlu Zhang, Asim Mahmood, Yuling Meng, Zheng Gang Zhang, Daniel C. Morris and Michael Chopp

Object

Thymosin β4 (Tβ4) is a regenerative multifunctional peptide. The aim of this study was to test the hypothesis that Tβ4 treatment initiated 6 hours postinjury reduces brain damage and improves functional recovery in rats subjected to traumatic brain injury (TBI).

Methods

Traumatic brain injury was induced by controlled cortical impact over the left parietal cortex in young adult male Wistar rats. The rats were randomly divided into the following groups: 1) saline group (n = 7); 2) 6 mg/kg Tβ4 group (n = 8); and 3) 30 mg/kg Tβ4 group (n = 8). Thymosin β4 or saline was administered intraperitoneally starting at 6 hours postinjury and again at 24 and 48 hours. An additional group of 6 animals underwent surgery without TBI (sham-injury group). Sensorimotor function and spatial learning were assessed using the modified Neurological Severity Score and the Morris water maze test, respectively. Animals were euthanized 35 days after injury, and brain sections were processed to assess lesion volume, hippocampal cell loss, cell proliferation, and neurogenesis after Tβ4 treatment.

Results

Compared with saline administration, Tβ4 treatment initiated 6 hours postinjury significantly improved sensorimotor functional recovery and spatial learning, reduced cortical lesion volume and hippocampal cell loss, and enhanced cell proliferation and neurogenesis in the injured hippocampus. The high dose of Tβ4 showed better beneficial effects compared with the low-dose treatment.

Conclusions

Thymosin β4 treatment initiated 6 hours postinjury provides both neuroprotection and neurorestoration after TBI, indicating that Tβ4 has promising therapeutic potential in patients with TBI. These data warrant further investigation of the optimal dose and therapeutic window of Tβ4 treatment for TBI and the associated underlying mechanisms.

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Yanlu Zhang, Michael Chopp, Yuling Meng, Zheng Gang Zhang, Edith Doppler, Asim Mahmood and Ye Xiong

Object

Cerebrolysin is a unique peptide preparation that mimics the action of neurotrophic factors. This study was designed to investigate the effects of acute treatment of experimental closed head injury (CHI) in rats with Cerebrolysin on neurological function.

Methods

Adult male Wistar rats (n = 60) were subjected to impact acceleration–induced CHI. Closed head injured rats received intraperitoneal injection of saline (n = 30) or Cerebrolysin (2.5 ml/kg, n = 30) starting 1 hour postinjury and administered once daily until they were killed (2 or 14 days after CHI). To evaluate functional outcome, the modified neurological severity score (mNSS), foot fault, adhesive removal, and Morris water maze (MWM) tests were performed. Animals were killed on Day 14 (n = 20) after injury, and their brains were removed and processed for measurement of neuronal cells, axonal damage, apoptosis, and neuroblasts. The remaining rats (n = 40) were killed 2 days postinjury to evaluate cerebral microvascular patency by fluorescein isothiocyanate (FITC)–dextran perfusion (n = 16) and to measure the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinase–9 (MMP-9) by using real-time reverse transcriptase-polymerase chain reaction (RT-PCR, n = 8) and by immunohistochemical analysis (n = 16).

Results

At 14 days post-CHI, the Cerebrolysin treatment group exhibited significant improvements in functional outcomes (the adhesive removal, mNSS, foot-fault, and MWM tests), and significantly more neurons and neuroblasts were present in the dentate gyrus (DG) (p < 0.05) compared with the saline-treated group (p < 0.05). At 2 days post-CHI, the Cerebrolysin group exhibited a significantly higher percentage of phosphorylated neurofilament H (pNF-H)–positive staining area in the striatum (p < 0.05), a significant increase in the percentage of FITC-dextran perfused vessels in the brain cortex (p < 0.05), a significant increase in the number of VEGF-positive cells (p < 0.05), and a significant reduction in the MMP-9 staining area (p < 0.05) compared with the saline-treated group. There was no significant difference in mRNA levels of MMP-9 and VEGF in the hippocampus and cortex 48 hours postinjury between Cerebrolysin- and saline-treated rats that sustained CHI.

Conclusions

Acute Cerebrolysin treatment improves functional recovery in rats after CHI. Cerebrolysin is neuroprotective for CHI (increased neurons in the dentate gyrus and the CA3 regions of the hippocampus and increased neuroblasts in the dentate gyrus) and may preserve axonal integrity in the striatum (significantly increased percentage of pNF-H–positive tissue in the striatum). Reduction of MMP-9 and elevation of VEGF likely contribute to enhancement of vascular patency and integrity as well as neuronal survival induced by Cerebrolysin. These promising results suggest that Cerebrolysin may be a useful treatment in improving the recovery of patients with CHI.

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Jie Cao, Hang Lin, Min Lin, Kaifu Ke, Yunfeng Zhang, Yong Zhang, Weihong Zheng, Xingyu Chen, Wei Wang, Meng Zhang, Jinggang Xuan, Ya Peng and for the REDIRECT Trial Investigators

OBJECTIVE

The RECO flow restoration (FR) device is a new stent retriever designed for rapid flow restoration in acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). Here, the authors compared the efficacy and safety of the RECO device with the predicate Solitaire FR stent retriever.

METHODS

The RECO Flow Restoration Device Versus Solitaire FR With the Intention for Thrombectomy Study (REDIRECT) was a multicenter, prospective, open randomized controlled trial. Patients with acute LVO at 7 Chinese stroke centers participated in the study. The primary efficacy endpoint was defined as a modified thrombolysis in cerebral infarction (mTICI) reperfusion grade ≥ 2 within three passes. The primary safety endpoint comprised any serious adverse device effect, symptomatic intracerebral hemorrhage (sICH), and any serious adverse event (SAE; defined as cerebral palsy or death) within 24 hours after the procedure. The secondary efficacy endpoints consisted of functional independence (modified Rankin Scale score 0–2), procedure duration, and 90-day all-cause mortality.

RESULTS

Between January 2014 and August 2016, 67 patients were randomly allocated to the RECO group and 69 patients to the Solitaire FR group. The primary efficacy endpoint (mTICI grade ≥ 2 within three passes) was similar in the two treatment groups (91% vs 87%, respectively, p = 0.5861), and the rate of reperfusion with an mTICI grade 2b/3 was 87% versus 75% (p = 0.1272). There were no serious adverse device effects in any patient. The rates of sICH (1.5% vs 7.2%, p = 0.1027) and SAEs (6.0% vs 1.4%, p = 0.2050) within 24 hours after the procedure were similar in the two treatment groups. There was no significant difference in the rate of functional independence (63% vs 46%, p = 0.0609) or 90-day all-cause mortality (13% vs 23%, p = 0.1848) or in procedure duration (85.39 ± 47.01 vs 89.94 ± 53.34 minutes, p = 0.5986) between the two groups.

CONCLUSIONS

The RECO stent retriever is effective and safe as a mechanical thrombectomy device for AIS due to LVO.

Clinical trial registration no.: NCT01983644 (clinicaltrials.gov)

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Yanlu Zhang, Michael Chopp, Yuling Meng, Mark Katakowski, Hongqi Xin, Asim Mahmood and Ye Xiong

OBJECT

Transplanted multipotent mesenchymal stromal cells (MSCs) improve functional recovery in rats after traumatic brain injury (TBI). In this study the authors tested a novel hypothesis that systemic administration of cell-free exosomes generated from MSCs promotes functional recovery and neurovascular remodeling in rats after TBI.

METHODS

Two groups of 8 Wistar rats were subjected to TBI, followed 24 hours later by tail vein injection of 100 μg protein of exosomes derived from MSCs or an equal volume of vehicle (phosphate-buffered saline). A third group of 8 rats was used as sham-injured, sham-treated controls. To evaluate cognitive and sensorimotor functional recovery, the modified Morris water maze, modified Neurological Severity Score, and foot-fault tests were performed. Animals were killed at 35 days after TBI. Histopathological and immunohistochemical analyses were performed for measurements of lesion volume, neurovascular remodeling (angiogenesis and neurogenesis), and neuroinflammation.

RESULTS

Compared with the saline-treated group, exosome-treated rats with TBI showed significant improvement in spatial learning at 34–35 days as measured by the modified Morris water maze test (p < 0.05), and sensorimotor functional recovery (i.e., reduced neurological deficits and foot-fault frequency) was observed at 14–35 days postinjury (p < 0.05). Exosome treatment significantly increased the number of newly generated endothelial cells in the lesion boundary zone and dentate gyrus and significantly increased the number of newly formed immature and mature neurons in the dentate gyrus as well as reducing neuroinflammation.

CONCLUSIONS

The authors demonstrate for the first time that MSC-generated exosomes effectively improve functional recovery, at least in part, by promoting endogenous angiogenesis and neurogenesis and by reducing inflammation in rats after TBI. Thus, MSC-generated exosomes may provide a novel cell-free therapy for TBI and possibly for other neurological diseases.

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Yuling Meng, Ye Xiong, Asim Mahmood, Yanlu Zhang, Changsheng Qu and Michael Chopp

Object

Delayed (24 hours postinjury) treatment with erythropoietin (EPO) improves functional recovery following experimental traumatic brain injury (TBI). In this study, the authors tested whether therapeutic effects of delayed EPO treatment for TBI are dose dependent in an attempt to establish an optimal dose paradigm for the delayed EPO treatment.

Methods

Experimental TBI was performed in anesthetized young adult male Wistar rats using a controlled cortical impact device. Sham animals underwent the same surgical procedure without injury. The animals (8 rats/group) received 3 intraperitoneal injections of EPO (0, 1000, 3000, 5000, or 7000 U/kg body weight, at 24, 48, and 72 hours) after TBI. Sensorimotor and cognitive functions were assessed using a modified neurological severity score and foot fault test, and Morris water maze tests, respectively. Animals were killed 35 days after injury, and the brain sections were stained for immunohistochemical analyses.

Results

Compared with the saline treatment, EPO treatment at doses from 1000 to 7000 U/kg did not alter lesion volume but significantly reduced hippocampal neuron loss, enhanced angiogenesis and neurogenesis in the injured cortex and hippocampus, and significantly improved sensorimotor function and spatial learning. The animals receiving the medium dose of 5000 U/kg exhibited a significant improvement in histological and functional outcomes compared with the lower or higher EPO dose groups.

Conclusions

These data demonstrate that delayed (24 hours postinjury) treatment with EPO provides dose-dependent neurorestoration, which may contribute to improved functional recovery after TBI, implying that application of an optimal dose of EPO is likely to increase successful preclinical and clinical trials for treatment of TBI.

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Ye Xiong, Asim Mahmood, Yuling Meng, Yanlu Zhang, Changsheng Qu, Timothy Schallert and Michael Chopp

Object

This efficacy study was designed to investigate traumatic brain injury (TBI) in rats treated with delayed erythropoietin (EPO) administered in a single dose compared with a triple dose.

Methods

Young adult male Wistar rats were randomly divided into the following groups: 1) sham group (6 animals); 2) TBI/saline group (6 animals); 3) TBI/EPO×1 group (6 animals); and 4) TBI/EPO×3 group (7 animals). Traumatic brain injury was induced by controlled cortical impact over the left parietal cortex. Erythropoietin (5000 U/kg) or saline was administered intraperitoneally on Day 1 (EPO×1 group) or on Days 1, 2, and 3 (EPO×3 group) postinjury. Neurological function was assessed using a modified neurological severity score, foot-fault, and Morris water maze tests. Animals were killed 35 days after injury and brain sections were stained for immunohistochemistry.

Results

Compared with the saline treatment, EPO treatment in both the EPO×1 and EPO×3 groups significantly reduced hippocampal cell loss, enhanced angiogenesis and neurogenesis in the injured cortex and hippocampus, and significantly improved neurological functional outcome. The EPO×3 group exhibited significantly improved functional and histological outcomes compared with the EPO×1 group.

Conclusions

These data demonstrate that delayed posttraumatic administration of EPO significantly improved histological and long-term functional outcomes in rats after TBI. The triple doses of delayed EPO treatment produced better histological and functional outcomes in rats, although a single dose provided substantial benefits compared with saline treatment.