Imaging Analysis of Primary Malignant Intracranial Lymphoma

OBJECTIVE To investigate the images characteristics of primarymalignant intracranial lymphoma .METHODS Retrospective study was conducted on CT/MRIimaging characteristics of 9 cases with primary malignantintracranial lymphoma.RESULTS The patients had lesions mostly in the supratentorialregion, including the parts of deep white matter, para-ependymalregions, and corpus callosum. The shapes of the lesions wereround or irregular. CT scan showed equal or slightly high densityof the tumor images, compared with the normal tissue in the brain.The T1 WI of MRI scan on the tumor showed low signal and theT2WI showed equal or slightly high signal. The MRI signals werehomogenous. Cystic lesion, calcification, and hemorrhage wererarely seen in MRI. Edema around tumor and its occupationaleffect was lessened. Edema around tumor shown in MRI was notin accordance with the true volume of the tumor mass. Enhancedscan on the lesions showed homogenous enhancement, and thepia mater invaded and/or the spread along ependyma.CONCLUSION Images of primary malignant intracraniallymphoma have specific characteristics that are useful in itsdiagnosis and differential diagnosis.

The Microscopic Surgical Treatment for Tumor of Posterior Cranial Fossa in Children

OBJECTIVE To analyze and discuss about the clinicalcharacteristics, pathological types, surgical modalities andtechniques, and postoperative complications in children withtumor of posterior cranial fossa .METHODS Retrospective study was conducted on 102 cases ofpediatric tumor of posterior cranial fossa, admitted and treated inour hospital during the period of January 1996 to January 2007.All patients underwent microscopic surgical treatment. Fifty-eight were male and 44 cases were female. The age ranged from 9months to 14 years old, with an average of 6.1 ± 0.5 of age. CranialCT or MRI examination was conducted before and after thesurgery on all patients.RESULTS The primary manifestations for this group of patientswere increased intracranial pressure and/or ataxia. Postoperativepathological diagnoses showed: 46 cases of medulloblastoma, 43cases of astrocytoma, 11 cases of ependymoma (including 1 caseof degenerative ependymoma), 1 case of dermoid cyst, and 1 caseof teratoma. In this group of the patients, radical surgery wasused in 68 cases and subtotal surgical removal used in 31 cases,while surgical removal of large section was performed on 3 cases.There were no deaths from surgery reported. Ninety-one casesshowed significant symptomatic improvement when comparedwith preoperative conditions, while 11 cases showed either noimprovement or more severely affected afterward. For 6 cases,postoperative ventriculoperitoneal shunt was performed within7 days to 2 months after the surgery. Sixty-three patients gainedfollow-up for 3 to 60 months in duration. Thirty-nine patientsregained normal life and were able to learn well, while there were7 patients who could not live normally on their own. During thefollow-up period, there were 17 cases of recurrence and 7 casesof death. In 23 cases of medulloblastoma in children with age of3 years old or above, 2 cases who underwent surgical removal ofintracranial ependymoma received small dosage of postoperativeX-ray radiotherapy on the the brain and spinal cord. Nine casesof medulloblastoma in children under age of 3 and 17 cases ofastrocytoma diagnosed after the surgery received chemotherapyof Carmustine.CONCLUSION Medulloblastomas and astrocytomas werethe most common types of pediatric tumor of posterior cranialfossa, right followed by ependymoma, and dermoid cysts andteratomas were rare. Early correct diagnosis, proper selection ofappropriate surgical modality and the surgical margin, propertreatment of postoperative complications, and the selecting rightradiotherapy or chemotherapy were the key factors in influencingthe prognostic outcome of children with tumor of posterior cranialfossa.

MicroRNA-670 aggravates cerebral ischemia/reperfusion injury via the Yap pathway

Apoptosis is an important programmed cell death process involved in ischemia/reperfusion injury.MicroRNAs are considered to play an important role in the molecular mechanism underlying the regulation of cerebral ischemia and reperfusion injury.However,whether miR-670 can regulate cell growth and death in cerebral ischemia/reperfusion and the underlying mechanism are poorly understood.In this study,we established mouse models of transient middle artery occlusion and Neuro 2a cell models of oxygen-glucose deprivation and reoxygenation to investigate the potential molecular mechanism by which miR-670 exhibits its effects during cerebral ischemia/reperfusion injury both in vitro and in vivo.Our results showed that after ischemia/reperfusion injury,miR-670 expression was obviously increased.After miR-670 expression was inhibited with an miR-670 antagomir,cerebral ischemia/reperfusion injury-induced neuronal death was obviously reduced.When miR-670 overexpression was induced by an miR-670 agomir,neuronal apoptosis was increased.In addition,we also found that miR-670 could promote Yap degradation via phosphorylation and worsen neuronal apoptosis and neurological deficits.Inhibition of miR-670 reduced neurological impairments after cerebral ischemia/reperfusion injury.These results suggest that microRNA-670 aggravates cerebral ischemia/reperfusion injury through the Yap pathway,which may be a potential target for treatment of cerebral ischemia/reperfusion injury.The present study was approved by the Institutional Animal Care and Use Committee of China Medical University on February 27,2017(IRB No.2017PS035K).

Ghrelin alleviates 6-hydroxydopamine-induced neurotoxicity in SH-SY5Y cells

Ghrelin is a neuropeptide that has various physiological functions and has been demonstrated to be neuroprotective in a number of neurological disease models.However,the underlying mechanisms of ghrelin in Parkinson’s disease remain largely unexplored.The current study aimed to study the effects of ghrelin in a 6-hydroxydopamine(6-OHDA)-induced Parkinson’s disease model and evaluate the potential underlying mechanisms.In the present study,we treated an SH-SY5 Y cell model with 6-OHDA,and observed that pretreatment with different concentrations of ghrelin(1,10,and 100 nM)for 30 minutes relieved the neurotoxic effects of 6-OHDA,as revealed by Cell Counting Kit-8 and Annexin V/propidium iodide(PI)apoptosis assays.Reverse transcription quantitative polymerase chain reaction and western blot assay results demonstrated that 6-OHDA treatment upregulatedα-synuclein and lincRNA-p21 and downregulated TG-interacting factor 1(TGIF1),which was predicted as a potential transcription regulator of the gene encodingα-synuclein(SNCA).Ghrelin pretreatment was able to reverse the trends caused by 6-OHDA.The Annexin V/PI apoptosis assay results revealed that inhibiting eitherα-synuclein or lincRNA-p21 expression with small interfering RNA(siRNA)relieved 6-OHDA-induced cell apoptosis.Furthermore,inhibiting lincRNA-p21 also partially upregulated TGIF1.By retrieving information from a bioinformatics database and performing both double luciferase and RNA immunoprecipitation assays,we found that lincRNA-p21 and TGIF1 were able to form a double-stranded RNA-binding protein Staufen homolog 1(STAU1)binding site and further activate the STAU1-mediated mRNA decay pathway.In addition,TGIF1 was able to transcriptionally regulateα-synuclein expression by binding to the promoter of SNCA.The Annexin V/PI apoptosis assay results showed that either knockdown of TGIF1 or overexpression of lincRNA-p21 notably abolished the neuroprotective effects of ghrelin against 6-OHDA-induced neurotoxicity.Collectively,these findings suggest that ghrelin exerts neuroprotective effects against 6-OHDA-induced neurotoxicity via the lincRNA-p21/TGIF1/α-synuclein pathway.