Atsuhito Uneda

A protein transduction method using oligo-arginine (3R) for the delivery of transcription factors into cell nuclei

Protein transduction with cell-penetrating peptides such as poly-arginine and HIV TAT peptides is widely used to deliver proteins, peptides, siRNA and biologically active compounds. It has been thought that poly-arginine peptides transduce proteins in a manner dependent on the number of arginine residues and oligo-peptides such as three arginines (3R) are ineffective. Here we showed that 3R-fused proteins were effectively delivered and functioned in cells co-treated with pyrenebutyrate, a counteranion bearing an aromatic hydrophobic moiety. Little 3R was transduced in glioma cells without pyrenebutyrate whereas the oligo-arginine was effectively delivered with pyrenebutyrate. Enhanced green fluorescence protein (eGFP) fused with 3R was effectively delivered into various kinds of cells including primary cultured cells and suspended cells in the presence of pyrenebutyrate. p53 fused with 3R (3R-p53) was delivered into glioma cells without pyrenebutyrate but could not be translocated into the nucleus. In contrast, 3R-p53 was observed in nuclei of glioma cells when co-applied with pyrenebutyrate. Although 3R-p53 was delivered less effectively than 11R-p53 with pyrenebutyrate, its transcriptional activity was higher than that of 11R-p53. Moreover, a single administration of 3R-p53 with pyrenebutyrate significantly inhibited the growth of cancer cells. These results suggest protein transduction using an oligo-arginine (3R) with pyrenebutyrate to be a good tool for the delivery of functional transcription factors and a promising method of treating cancer.

Combining poly-arginine with the hydrophobic counter-anion 4-(1-pyrenyl)-butyric acid for protein transduction in transdermal delivery.

Topical therapy is the most favored form of treatment for whitening against hyperpigmentation and sunburn because it lends itself to self-administration, patient compliance, and absence of systemic adverse effects. However, transdermal delivery of hydrophilic chemicals is difficult. The main purpose of this study is to develop a delivering system of hydrophilic drugs and proteins across the skin. Hydroquinone (HQ), a well-known tyrosinase inhibitor and antimelanogenesis compound, and enhanced green fluorescent protein (EGFP) were fused with eleven poly-arginine (11R). Both HQ-11R and EGFP-11R were efficiently delivered in B16 cells, a mouse melanoma cell line. HQ-11R was as effective as HQ alone at inhibiting melanin synthesis in B16 cells. EGFP-11R was efficiently delivered into cells of the epidermis with 4-(1-pyrenyl)-butyric acid (PB), a counteranion bearing an aromatic hydrophobic moiety, in vivo, but EGFP alone or EGFP-11R without PB was not. Finally, topical application of HQ-11R with PB significantly inhibited UV irradiation-induced pigmentation in guinea pigs compared with HQ alone. These results suggest that topical therapy using poly-arginine in combination with PB is useful for the delivery of hydrophilic drugs and proteins by the transdermal route.

Neurofibromatosis type 1-associated extracranial vertebral artery aneurysm complicated by vertebral arteriovenous fistula after rupture: Case report and literature review.

BACKGROUND Extracranial vertebral artery aneurysm related to neurofibromatosis type 1 (NF1) is rare. Aneurysmal rupture typically induces such symptoms as cervical hematoma, hemothorax, and hypotension. Here we report a case of ruptured extracranial vertebral artery aneurysm in a patient with NF1 who, rather than cervical hematoma, hemothorax, or hypotension, developed a vertebral arteriovenous fistula (AVF) after aneurysm rupture. CASE DESCRIPTION A 35-year-old woman with a family history of NF1 presented with sudden-onset right neck and shoulder pain. Computed tomography angiography showed a right extracranial vertebral artery aneurysm. She had neither a cervical hematoma nor hypotension; however, angiography showed an AVF secondary to aneurysmal rupture. The patient was treated with endovascular coil embolization to prevent re-rupture. Postoperatively, her right neck and shoulder pain improved, and she was discharged without further neurologic deficits. CONCLUSIONS This patients clinical course suggests that if there is minimal bleeding from an NF1-associated ruptured extracranial vertebral artery aneurysm, then typical symptoms, such as cervical hematoma, hemothorax, and hypotension, may be absent. Thus, ruptured extracranial vertebral artery aneurysm should be considered in the differential diagnosis of patients with NF1 with sudden-onset radiculopathy, even in the absence of typical symptoms. The detection of a vertebral AVF provides a useful clue to the diagnosis of aneurysm rupture in such cases.

A case of dumbbell-shaped epidural cavernous angioma in the lumbar spine.

Background: Most spinal cavernous haemangiomas occur in the vertebral body and purely extradural cavernous hemangiomas without any vertebral body involvement is rare and account for only 4% of all extradural spinal tumors. Dumbbell-shaped spinal cavernous angioma is extremely rare, only 10 cases have been reported in the literature. Case Description: A 77-year-old female presented with a one-year history of lumbago and right-sided L3 dermatomal hypoesthesia. A dumbbell mass at the L2/3 vertebral level was identified on lumbar MRI. The lesion was irregularly shaped and isointense on T1W and hyperintense on T2W and DWI images with homogenous contrast enhancement. A presumptive diagnosis was schwannoma, but other malignant neoplasms were also considered because of its irregular shape, minimally dilated neural foramen and the involvement of the non-enhanced L3 nerve root. The patient underwent surgery with a lateral extracavitary approach. A histopathological examination revealed cavernous hemangioma. Conclusion: Cavernous hemangioma should be included in the differential diagnosis of dumbbell-shaped spinal tumors when the intervertebral foramina is not highly dilated and non-enhanced nerve root is identified in the tumor.

Fibroblast growth factor 13 regulates glioma cell invasion and is important for bevacizumab-induced glioma invasion

Glioblastoma has the poorest prognosis, and is characterized by excessive invasion and angiogenesis. To determine the invasive mechanisms, we previously used two glioma cell lines (J3T-1 and J3T-2) with different invasive phenotypes. The J3T-1 showed abundant angiogenesis and tumor cell invasion around neovasculature, while J3T-2 showed diffuse cell infiltration into surrounding healthy parenchyma. Microarray analyses were used to identify invasion-related genes in J3T-2 cells, and the expressed genes and their intracellular and intratumoral distribution patterns were evaluated in J3T-2 cell lines, human glioma cell lines, human glioblastoma stem cells and human glioblastoma specimens. To determine the role of the invasion-related genes, invasive activities were evaluated in vitro and in vivo. Fibroblast growth factor 13 (FGF13) was overexpressed in J3T-2 cells compared to J3T-1 cells, and in human glioma cell lines, human glioblastoma stem cells and human glioblastoma specimens, when compared to that of normal human astrocytes. Immunohistochemical staining and the RNA-seq (sequencing) data from the IVY Glioblastoma Atlas Project showed FGF13 expression in glioma cells in the invasive edges of tumor specimens. Also, the intracellular distribution was mainly in the cytoplasm of tumor cells and colocalized with tubulin. Overexpression of FGF13 stabilized tubulin dynamics in vitro and knockdown of FGF13 decreased glioma invasion both in vitro and in vivo and prolonged overall survival of several xenograft models. FGF13 was negatively regulated by hypoxic condition. Silencing of FGF13 also decreased in vivo bevacizumab-induced glioma invasion. In conclusion, FGF13 regulated glioma cell invasion and bevacizumab-induced glioma invasion, and could be a novel target for glioma treatment.

Importance of Recognizing Carpal Tunnel Syndrome for Neurosurgeons: A Review

Idiopathic carpal tunnel syndrome (CTS) is a common complaint, reflecting entrapment neuropathy of the upper extremity. CTS produces symptoms similar to those of other conditions, such as cervical spondylosis or ischemic or neoplastic intracranial disease. Because of these overlaps, patients with CTS are often referred to a neurosurgeon. Surgical treatment of CTS was started recently in our department. Through this experience, we realized that neurosurgeons should have an increased awareness of this condition so they can knowledgeably assess patients with a differential diagnosis that includes CTS and cervical spinal and cerebral disease. We conducted a literature review to gain the information needed to summarize current knowledge on the clinical, pathogenetic, and therapeutic aspects of CTS. Because the optimal diagnostic criteria for this disease are still undetermined, its diagnosis is based on the patient’s history and physical examination, which should be confirmed by nerve conduction studies and imaging modalities such as magnetic resonance imaging and ultrasonography. Treatment methods include observation, medication, splinting, steroid injections, and surgical intervention. Understanding the clinical features and pathogenesis of CTS, as well as the therapeutic options available to treat it, is important for neurosurgeons if they are to provide the correct management of patients with this disease.

Brain abscess caused by Nocardia asiatica.

Background: Nocardia infection of the central nervous system leading to brain abscess is a rare condition but has a high mortality rate. Among the species of Nocardia, only three cases of brain abscess due to Nocardia asiatica infection have been reported. Case Description: A 65-year-old man with a history of autoimmune hemolytic anemia treated with prednisolone presented to our hospital because of occipital headache. Brain magnetic resonance imaging showed bilateral occipital lesions. The patient underwent craniotomy and resection of the left occipital lobe lesion. N. asiatica was identified by 16S rRNA sequencing of the resected specimen. Treatment with trimethoprim/sulfamethoxazole led to a complete resolution of the brain lesion. Conclusion: Because of the different antimicrobial sensitivity patterns among Nocardia species, both appropriate subtyping and susceptibility testing of uncommon species such as N. asiatica are required for the successful treatment of nocardial infections.

Tandem cervical/intracranial internal carotid artery occlusion due to cardiac myxoma treated successfully with mechanical endovascular thrombectomy.

Dear Editor, Ischemic stroke due to cardiac myxomas is a rare condition without established therapeutic strategies. Acute cervical internal carotid artery (ICA) occlusion due to cardiac myxoma has a poor prognosis, especially when there are tandem lesions caused by intracranial migration of tumorous emboli [3, 8]. Here, we describe the first reported case of a patient with tandem cervical ICA/ICA terminus occlusion subsequent to cardiac myxoma that was successfully treated with mechanical endovascular thrombectomy. A 70-year-old right-handedman who reported sudden right hemiparesis and speech disturbance was transported to our hospital 46 min after symptom onset. His National Institute of Health Stroke Scale (NIHSS) score was 11. Brain magnetic resonance imaging (MRI) using diffusion-weighted imaging demonstrated bilateral multiple small increased-signal lesions due tomultiple small emboli (Fig. 1a). Onmagnetic resonance angiography (MRA) of the head and neck, there was a lack of signal corresponding to the left common carotid artery (CCA) and to the ICA (Fig. 1b, c). Intravenous recombinant tissue plasminogen inhibitor (rtPA) was administered 2 h and 55min after symptom onset but did not achieve neurological improvement. Emergent cerebral angiography was performed via the right femoral artery. Immediately after the start of angiography, the patient’s level of consciousness decreased. Although MRA before rtPA showed collateral flow to the left MCA through the anterior communicating artery, angiography of the right CCA now showed a left carotid T-occlusion (Fig. 1d). Angiography of the left CCA showed left cervical ICA occlusion (Fig. 1e). Together, these results suggested the migration of a large emboli distally into the left ICA terminus, resulting in neurological deterioration. A balloon guide catheter was placed in the left cervical ICA. Three passes with a Penumbra 5MAX ACE catheter (Penumbra, Alameda, CA, USA) resulted in revascularization of the left ICA and the left M1 segment, but the left inferiorM2-branch remained occluded. A single pass with a Trevo retriever (Stryker Neurovascular, Mountain View, CA, USA) resulted in successful recanalization, thrombolysis in cerebral infarction (TICI) grade 2B (Fig. 1f) [5], 6 h and 20 min after symptom onset. The retrieved emboli were whitish-to-reddish, gelatinous, and friable, with a total length >10 cm (Fig. 1g). A postoperative brain MRI showed new symptomatic ischemic lesions in the left MCA territory, but those were limited to the frontal lobe (Fig. 1h). Recanalization of the left ICA and the MCA was observed on MRA (Fig. 1i, j). A pathological examination showed that the retrieved emboli consisted of tumorous tissue from a myxoma (Fig. 1k). Transesophageal echocardiography results confirmed a mass in the left atrium (Fig. 1l). The cardiac mass was resected by open-heart surgery 6 days after the stroke. Three months after the stroke, the patient’s NIHSS score was 1, because of mild aphasia and the modified Rankin Scale score was 2. Although cardiac myxoma is responsible for <1 % of all cases of ischemic stroke [1], it should be considered in the differential diagnosis. The cerebral artery most commonly affected by ischemic stroke due to cardiac myxoma is the MCA (65 %) [12]. ICA involvement by embolic occlusion due to cardiac myxoma is relatively rare (11 %) [12], and cervical ICA occlusion due to cardiac myxoma even rarer. To our knowledge, there are only three reported cases of cervical ICA occlusion subsequent to cardiac myxoma including our * Atsuhito Uneda uneda-oka@umin.ac.jp

Olfactory neuroblastoma followed by emergency surgery for symptomatic intradural spinal metastasis: A case report

Background: Olfactory neuroblastoma (ONB) is a rare, aggressive tumor of the nasal cavity. It may invade the paranasal cavities and anterior skull base locally but may also metastasize to the cervical lymph nodes, lungs, or distant central nervous system. Case Description: Here, we report a case of ONB in which emergency surgery was performed for intradural spinal metastasis (ISM). The patient was a 52-year-old male who underwent surgery for ONB. The tumor extended from the nasal cavity to the intracranial space and was resected completely. After radiotherapy (60 Gy), the patient was discharged without any neurological deficit except anosmia. Seven months after the surgery, he consulted our department because of progressive tetraparesis. Cervical magnetic resonance imaging demonstrated an intradural spinal mass involving C5–T2 and necessitating emergency surgery. The tumor was resected subtotally followed by 58 Gy whole-spine irradiation. The patients neurological symptoms improved, however, paralysis of the right upper and both the lower limbs remained. During the 4 months between the spinal surgery and his death, there was no further motor deterioration in any of his four extremities. Conclusion: This case demonstrates the need to be aware of potential ISM in the follow-up of patients with ONB. The early detection of ISM by spinal MRI is crucial to ensuring good palliative care.

The Importance of Recognizing Diffuse Idiopathic Skeletal Hyperostosis for Neurosurgeons: A Review

Diffuse idiopathic skeletal hyperostosis (DISH) is characterized by calcification and ossification of the soft tissues, mainly ligaments and entheses. The spines of patients with DISH generally become increasingly rigid and osteoporotic, and fractures may occur after even a relatively minor traumatic event such as a ground-level fall. Moreover, the prevalence of DISH may be rapidly increasing in affluent societies. Thus, awareness of this condition is becoming more important for neurosurgeons when assessing trauma patients. For the present article, a literature review was conducted to summarize the current clinical, pathogenetic, and therapeutic knowledge of this disease. Furthermore, current treatment strategies for DISH-related spine injuries are also reviewed. Although the recommended treatment for spinal injuries in DISH patients is surgical, mainly through long-segment posterior fusion, rather than conservative options, stable fractures without any associated neurologic deficits have often been successfully managed with immobilization alone. Percutaneous instrumentation and the use of teriparatide may be useful depending on the surgical risks and patient neurological status.