Down-regulating microRNA-20a regulates CDH1 to protect against cerebral ischemia/reperfusion injury in rats.

Studies have extensively focused on the involvement of microRNAs (miRNAs) in cerebral ischemia/reperfusion (I/R) injury but not much on the specific role of miR-20a. Hence, this study is purposed to decipher whether miR-20a could regulate cadherin 1 (CDH1) to affect cerebral I/R injury in rats. Rat transient middle cerebral artery occlusion model (MCAO) was established. Rats were injected with lentiviral solution containing miR-20a inhibitor, or overexpressed CDH1 or combined depleted miR-20a and CDH1 to explore their roles in cerebral I/R injury. Oxidative stress-related factors, miR-20a, CDH1, nuclear factor-kappaB (NF-κB) and Nestin expression in brain tissues were detected by RT-qPCR and western blot assay. The target relation between miR-20a and CDH1 was predicted by online website and further confirmed by luciferase activity assay. In rats with cerebral I/R injury, increased miR-20a and decreased CDH1 were found in brain tissues. Reduction of miR-20a or elevation of CDH1 attenuated behavior function in MCAO rats. Inhibiting miR-20a or restoring CDH1 restrained oxidative stress, attenuated pathological damage of neurons, promoted neuron survival, and down-regulated NF-κB and Nestin expression in brain tissues of MCAO rats. CDH1 was determined to a target gene of miR-20a. This study elucidates that down-regulating miR-20a elevates CDH1 to protect neurons from cerebral I/R injury, which paves a new way for treatment of cerebral I/R injury.

Neuroprotection mediated by the Wnt/Frizzled signaling pathway in early brain injury induced by subarachnoid hemorrhage.

The Wnt/Frizzled signaling pathway participates in many inflammation-linked diseases. However, the inflammatory response mediated by the Wnt/Frizzled signaling pathway in experimental subarachnoid hemorrhage has not been thoroughly investigated. Consequently, in this study, we examined the potential role of the Wnt/Frizzled signaling pathway in early brain injury in rat models of subarachnoid hemorrhage. Simultaneously, possible neuroprotective mechanisms were also investigated. Experimental subarachnoid hemorrhage rat models were induced by injecting autologous blood into the prechiasmatic cistern. Experiment 1 was designed to examine expression of the Wnt/Frizzled signaling pathway in early brain injury induced by subarachnoid hemorrhage. In total, 42 adult rats were divided into sham (injection of equivalent volume of saline), 6-, 12-, 24-, 48-, 72-hour, and 1-week subarachnoid hemorrhage groups. Experiment 2 was designed to examine neuroprotective mechanisms of the Wnt/Frizzled signaling pathway in early brain injury induced by subarachnoid hemorrhage. Rats were treated with recombinant human Wnt1 (rhwnt1), small interfering Wnt1 (siwnt1) RNA, and monoclonal antibody of Frizzled1 (anti-Frizzled1) at 48 hours after subarachnoid hemorrhage. Expression levels of Wnt1, Frizzled1, ß-catenin, peroxisome proliferator-activated receptor-γ, CD36, and active nuclear factor-κB were examined by western blot assay and immunofluorescence staining. Microglia type conversion and inflammatory cytokine levels in brain tissue were examined by immunofluorescence staining and enzyme-linked immunosorbent assay. Our results show that compared with the sham group, expression levels of Wnt1, Frizzled1, and ß-catenin were low and reduced to a minimum at 48 hours, gradually returning to baseline at 1 week after subarachnoid hemorrhage. rhwnt1 treatment markedly increased Wnt1 expression and alleviated subarachnoid hemorrhage-induced early brain injury (within 72 hours), including cortical cell apoptosis, brain edema, and neurobehavioral deficits, accompanied by increasing protein levels of ß-catenin, CD36, and peroxisome proliferator-activated receptor-γ and decreasing protein levels of nuclear factor-κB. Of note, rhwnt1 promoted M2-type microglia conversion and inhibited release of inflammatory cytokines (interleukin-1ß, interleukin-6, and tumor necrosis factor-α). In contrast, siwnt1 RNA and anti-Frizzled1 treatment both resulted in an opposite effect. In conclusion, the Wnt/Frizzled1 signaling pathway may participate in subarachnoid hemorrhage-induced early brain injury via inhibiting the inflammatory response, including regulating microglia type conversion and decreasing inflammatory cytokine release. The study was approved by the Animal Ethics Committee of Anhui Medical University and First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China (approval No. LLSC-20180202) in May 2017.

Free perforating branch flap for primary repairing the huge soft-tissue defects on the scalp and face.

OBJECTIVE: This study aimed to explore the effect of free perforating branch flap on the reconstruction of huge soft-tissue defects on the scalp and face. METHODS: Sixteen cases of huge soft-tissue defects on the scalp and face were reconstructed by nine latissimus dorsi-free perforator flaps and seven anterolateral thigh-free perforator flaps. The defects area was from 12 cm× 7 cm to 20 cm × 11 cm, while the flaps area was from 14 cm × 8 cm to 23 cm × 12 cm. The survival, planeness, chromatic aberration, radiotherapy toleration of flap and the function, scar of donor site were observed postoperatively. RESULT: All of the flaps were survived completely, and 15 cases presented for primary reconstruction; one underwent secondary reconstruction. One of the patients died one-year postoperatively due to intracranial tumor recurrence and the others had no recurrence. All of the flaps showed perfect shape and appropriate thickness. No roentgen ulcer was observed except for some extent of chromatic aberration. The donor-site scar was larvaceous and the function was good. CONCLUSION: This study indicated that the latissimus dorsi-free perforator flap or anterolateral thigh-free perforator flap was an ideal choice for the reconstruction of defects on the scalp and face.

Safety and efficacy of frameless stereotactic brain biopsy techniques.

OBJECTIVE: To explore the safety and efficacy of frameless stereotactic brain biopsy. METHODS: Diagnostic accuracy was calculated by comparing biopsy diagnosis with definitive pathology in 62 patients who underwent frameless stereotactic brain biopsy between January 2008 and December 2010 in Xiamen University Southeast Hospital. Preoperative characteristics and histological diagnosis were reviewed and then information was analysed to identify factors associated with the biopsy not yielding a diagnosis and complications. RESULTS: Diagnostic yield was 93.5%. No differences were found between pathological diagnosis and frozen pathological diagnosis. The most common lesions were astrocytic lesions, included 16 cases of low-grade glioma and 12 cases of malignant glioma. Remote hemorrhage, metastasis, and lymphoma were following in incidence. Multiple brain lesions were found in 17 cases (27.4%). Eleven cases were frontal lesions (17.7%), 8 were frontotemporal (12.9%), 6 were frontoparietal (9.7%), and 5 each were temporal, parietal, and parietotemporal lesions (8.1%). Postoperative complications occurred in 21.0% of the patients after biopsies, including 10 haemorrhages (16.1%) and 3 temporary neurological deficits (1 epilepsy, 1 headache, and 1 partial hemiparesis). No patient required operation for hematoma evacuation. CONCLUSION: Frameless stereotactic biopsy is an effective and safe technique for histologic diagnosis of brain lesions, particularly for multifocal and frontal lesions.

[Impulsive decision-making behaviors in heroin addicts: a study of functional magnetic resonance imaging].

OBJECTIVE: To explore the brain regions associated with impulsive decision-making behaviors and interpret the nervous mechanism for addiction and relapse in heroin abusers. METHODS: Using the paradigms of psychological experiment, the subjects in both heroin addiction group (HA group) and normal control group (HC group) performed Iowa gambling task (IGT) and simultaneously underwent functional magnetic resonance imaging (fMRI) scan. All the above data were gathered and then analyzed by SPM5 software to explore both the brain regions and their functional changes correlated with impulsive decision-making. RESULTS: Evidence by IGT behavioral consequences demonstrated that the net scores in HC group increased with numbers of decision-making whereas no increment (fluctuating between-1 and 0) was observed in HA group. Based on the results of fMRI analysis, right orbitofrontal cortex (OFC), dorsolateral prefrontal cortex (DLPFC), left ventromedial prefrontal cortex (MPFC) and anterior cingulate cortex (ACC) were activated in both groups. But the right OFC was more active while the right DLPFC and left MPFC were weaker in HA group versus the HC group. Meanwhile, activation of right lenticular nucleus, right thalamus, right insula, hippocampus and left caudate nucleus were observed in HA group. CONCLUSION: Heroin abusers are incapable of impulsive decision-making in behavioral studies. Such a brain region as prefrontal cortex participates in the decision-making performance and control of impulsiveness. Functionally abnormal brain regions correlated with impulsive decision-making may be one cause of genesis, maintenance and relapse of heroin addiction.