Effects of Ginkgo biloba extract EGb761 on neural differentiation of stem cells offer new hope for neurological disease treatment

Stem cell transplantation has brought new hope for the treatment of neurological diseases.The key to stem cell therapy lies in inducing the specific differentiation of stem cells into nerve cells.Because the differentiation of stem cells in vitro and in vivo is affected by multiple factors,the final differentiation outcome is strongly associated with the microenvironment in which the stem cells are located.Accordingly,the optimal microenvironment for inducing stem cell differentiation is a hot topic.EGb761 is extracted from the leaves of the Ginkgo biloba tree.It is used worldwide and is becoming one of the focuses of stem cell research.Studies have shown that EGb761 can antagonize oxygen free radicals,stabilize cell membranes,promote neurogenesis and synaptogenesis,increase the level of brain-derived neurotrophic factors,and replicate the environment required during the differentiation of stem cells into nerve cells.This offers the possibility of using EGb761 to induce the differentiation of stem cells,facilitating stem cell transplantation.To provide a comprehensive reference for the future application of EGb761 in stem cell therapy,we reviewed studies investigating the influence of EGb761 on stem cells.These started with the composition and neuropharmacology of EGb761,and eventually led to the finding that EGb761 and some of its important components play important roles in the differentiation of stem cells and the protection of a beneficial microenvironment for stem cell transplantation.

Malignant meningioma of the cerebellopontine angle in a 2-year-old girl:a case report and literature review

Meningioma is a common intracranial tumor in adults.Pediatric cases account for approximately 1.5% of all intracranial meningiomas,and very few cases show malignant histological features.Primary pediatric malignant meningioma in the cerebellopontine angle is extremely uncommon.Herein,we report a 2-yearold girl with malignant meningioma in the cerebellopontine angle.The clinical features,diagnosis,and treatment protocol are discussed.

Inflammatory Myofibroblastic Tumor Mimicking Malignant Meningioma in the Middle Cranial Fossa:a Case Report

INFLAMMATORY myofibroblastic tumor（IMT）,alsoknown as inflammatory pseudotumor or plasma cellgranulomas,is an uncommon fibro-inflammatorylesion which is composed of inflammatory cells andmyofibroblastic spindle cells.1Its pathogenesis is still un-known.The tumor commonly occurs in the lung,upperrespiratory tract,live,orbit,abdominal membrane,retro-peritoneum,and genitourinary tract.2-4It rarely involvesthe central nerve system,5,

Inflammatory myofibroblastic tumor of the central nervous system:A case report

BACKGROUND An inflammatory myofibroblastic tumor(IMT)occurring in the central nervous system is very rare,and thus its pathogenesis is unknown.This case report and literature review aimed to explore the pathogenesis,clinical features,imaging findings,pathological characteristics,immunohistochemical characteristics,diagnoses,treatments,and risks of postoperative recurrence of IMT in the central nervous system.CASE SUMMARY A 67-year-old woman was admitted to the hospital with an exophthalmic protrusion and double vision in the left eye that had persisted for 3 mo.Magnetic resonance imaging(MRI)showed a 2.4 cm×1.3 cm heterogeneous large mass in the bottom of the left anterior cranial fossa,which was closely related to the dura mater.Before surgery,we suspected the mass to be meningioma.The entire mass was successfully removed under neuronavigation and electrophysiological monitoring,and postoperative pathology indicated an IMT with extensive infiltration of chronic inflammatory cells and scattered multinucleated giant cells.Head MRI at the 3-mo follow-up showed that the tumor at the bottom of left anterior cranial fossa had been completely resected without recurrence.CONCLUSION From the histological,immunohistochemical,and genetic analyses,the present case suggests that the pathogenesis of IMT-CNS is related to autoimmunity.

tRNA cleavage: a new insight

Over the past decades,tRNA was found to be a rich hub of RNA modifications such as 1-methyladenosine and 5-methycytosine modifications and others,holding more than half of all modifications occurring in RNA molecules.Moreover,tRNA was discovered to be a source of various small noncoding RNA species,such as the stress induced angiogenin cleaved tRNA halves(tiRNA)or the miRNA like tRNA derived fragments.tRNA cleavage under stress was fist discovered in bacteria and later was found to be conserved across different species,including mammals.Under cellular stress conditions,tRNA undergoes conformational changes and angiogenin cleaves it into 3′and 5′halves.5′tiRNA halves were shown to repress protein translations.tRNA cleavage is thought of to be a cytoprotective mechanism by which cells evade apoptosis,however some data hints to the opposite;that tiRNA are cytotoxic or at least related to apoptosis initiation.tRNA cleavage also was shown to be affected by tRNA modifications via different enzymes in the cytosol and mitochondria.In this review,we will highlight the biology of tRNA cleavage,show the evidence of it being cytoprotective or a marker of cell death and shed a light on its role in disease models and human diseases as well as possible future directions in this field of RNA research.

Merging non-covalent and covalent crosslinking:En route to single chain nanoparticles

Single-chain nanoparticles represent an emerging class of nanomaterials designed to mimic protein's folding paradigm.Intrachain covalent crosslinking toward the formation of single-chain nanoparticles encounters complex energy landscapes,leading to the potential occurrence of misfolding issues.While noncovalent crosslinking can circumvent this issue,the resulting single-chain nanoparticles exhibit lower structural stability compared to their covalently crosslinked counterparts.In this study,we present a novel approach for the synthesis of single-chain nanoparticles,achieved through the combination of non-covalent and covalent intramolecular crosslinking.Cyanostilbenes grafted onto the linear polymer form intrachain non-covalent stacks aided by hydrogen bonds,leading to the formation of non-covalently crosslinked single-chain nanoparticles.These nanoparticles undergo conversion to covalently crosslinked nanostructures through subsequent photo-irradiation using[2+2]photocycloaddition,a process facilitated by the supramolecular confinement effect.Consequently,the resulting single-chain nanoparticles demonstrate both intrachain folding efficiency and substantial stability,offering significant potential for advancing applications across diverse fields.

Surgical treatment of symptomatic Rathke＇s cleft cysts： clinical features, therapy considerations and outcomes

Background Rathke＇s cleft cyst （RCC） is one of the most common incidentally discovered sellar lesions, while symptomatic cases are relatively rare. Surgical treatment is recommended for symptomatic patients to drain the cyst content and to remove the capsule safely. The aim of this study was to clarify the clinical features, surgery considerations and therapy outcomes of symptomatic RCCs. Methods Totally 42 patients （19 males and 23 females） were retrospectively reviewed with the diagnosis of RCCs under surgery resection at the Affiliated Hospital of Medical College, Qingdao University between January 2005 and December 2010. Results Patients＇ age ranged from 6 to 67 years （mean of 41.6 years）. The duration of symptoms ranged from 4 days to 10 years. Headache （69%）, visual impairment （36%）, and pituitary dysfunction （10%） were the most common presenting symptoms. The maximum diameter of cysts ranged from 6.0 to 46.7 mm （mean of 20.07 mm）. Of the 42 patients, 36 underwent endonasal transsphenoidal approach and the others underwent transcranial approach. Thirty patients had a subtotal resection and decompression, while 12 patients had a total cyst resection. Cysts of 28 patients were lined by simple cubical or columnar epithelium, and cysts of 34 patients were filled by amorphous colloid material, that was the characteristic of RCCs. The majority of patients presented with a simple headache, and 93% of this group experienced a complete improvement after surgery. Twelve of 15 patients （80%） with preoperative visual deficits experienced an improvement in their vision after surgery. All of those patients with pituitary dysfunction experienced an improved endocrine status. The endocrinological complication usually was diabetes insipidus, and postoperative transient diabetes insipidus occurred in 13 （31%） patients without any permanent diabetes insipidus. The overall recurrence rate was 7% at a mean follow-up of 22 months （range 12-60 months）. Conclusions Surgical treatment is to drain the contents of the cyst and to remove the capsule as much as possible under the precondition that does not increase the complications. Biopsy and decompression procedures are recommended for most cases.

Ultra-small nanodots coated with oligopeptides providing highly negative charges to enhance osteogenic differentiation of hBMSCs better than osteogenic induction medium

For bone regenerative engineering,it is a promising method to form skeletal tissues differentiating from human bone morrow mesenchyme stem cells(hBMSCs).However,it is still a critical challenge to efficiently control ostogenesis and clearly reveal the influence factor.To this end,the fluorescent gold nanodots(Au NDs) with highly negative charges as osteogenic induction reagent are successfully synthesized,which display better than commercial osteogenic induction medium through the investigations of ALP activity(2.5 folds) and cytoskeleton staining(1.5 folds).Two kinds of oligopeptides with different bio-structures(cysteine,Cys and glutathione,GSH) are selected for providing surficial charges on Au NDs.It is revealed that Au-Cys with more negative charges(-51 mV) play better role than Au-GSH(-19 mV) in osteogenic differentiation,when both of them have same size(~2 nm),sphere shape and show similar cell uptake amount.To explore deeply,osteogenesis related signaling pathways are monitored,revealing that the enhancement of osteogenic differentiation was through autophagy signaling pathway triggered by Au-Cys.And the promotion of highly negative charges in osteogenic diffe rentiation was further proved via sliver nanodots(Ag NDs,Ag-Cys and Ag-GSH) and carbon nanodots(CDs,Cys-CDs and GSH-CDs).This work indicates part of insights during hBMSCs differentiation and provides a novel strategy in osteogenic differentiation process.

Imaging Gliomas with Nanoparticle-Labeled Stem Cells

Objective： Gliomas are the most common neoplasm of the central nervous system （CNS）; however, traditional imaging techniques do not show the boundaries of tumors well. Some researchers have found a new therapeutic mode to combine nanoparticles, which are nanosized particles with various properties for specific therapeutic purposes, and stern cells for tracing gliomas. This review provides an introduction of the basic understanding and clinical applications of the combination of stem cells and nanoparticles as a contrast agent for glioma imaging. Data Sources： Studies published in English up to and including 2017 were extracted from the PubMed database with the selected key words of＂stem cell,＂ ＂glioma,＂ ＂nanoparticles,＂ ＂MRI,＂ ＂＇nuclear imaging,＂ and ＂Fluorescence imaging.＂ Study Selection： The selection of studies focused on both preclinical studies and basic studies of tracking glioma with nanoparticle-labeled stem cells. Results： Studies have demonstrated successful labeling of stem cells with multiple types of nanoparticles. These labeled stein cells efficiently migrated to gliomas of varies models and produced signals sensitively captured by different imaging modalities. Conclusion： The use of nanoparticle-labeled stem cells is a promising imaging platform for the tracking and treatment of gliomas.