Confinement in Dual-Chain-Locked DNA Origami Nanocages Programs Marker-Responsive Delivery of CRISPR/Cas9 Ribonucleoproteins.

Delivery of CRISPR/Cas9 ribonucleoproteins (RNPs) offers a powerful tool for therapeutic genome editing. However, precise manipulation of CRISPR/Cas9 RNPs to switch the machinery on and off according to diverse disease microenvironments remains challenging. Here, we present dual-chain-locked DNA origami nanocages (DL-DONCs) that can confine Cas9 RNPs in the inner cavity for efficient cargo delivery and dual-marker-responsive genome editing in the specified pathological states. By engineering of ATP or miRNA-21-responsive dsDNAs as chain locks on the DONCs, the permeability of nanocages and accessibility of encapsulated Cas9 RNPs can be finely regulated. The resulting DL-DONCs enabled steric protection of bioactive Cas9 RNPs from premature release and deactivation during transportation while dismounting the dual chain locks in response to molecular triggers after internalization into tumor cells, facilitating the escape of Cas9 RNPs from the confinement for gene editing. Due to the dual-marker-dominated uncaging mechanism, the gene editing efficiency could be exclusively determined by the combined level of ATP and miRNA-21 in the target cellular environment. By targeting the tumor-associated PLK-1 gene, the DL-DONCs-enveloped Cas9 RNPs have demonstrated superior inhibitory effects on the proliferation of tumor cells in vitro and in vivo. The developed DL-DONCs provide a custom-made platform for the precise manipulation of Cas9 RNPs, which can be potentially applied to on-demand gene editing for classified therapy in response to arbitrary disease-associated biomolecules.

DNA-Mediated Assembly of Carbon Nanomaterials.

Carbon nanomaterials (CNMs) have attracted extensive attentions on account of their superior electrical, mechanical, optical, and biological properties. However, the dimensional limit and irregular arrangement have hampered their further application. It is necessary to find an easy, efficient and controllable way to assemble CNMs into well-ordered array. DNA nanotechnology, owning to the advantages of precise programmability, highly structural predictability and spatial addressability, has been widely applied in the assembly of CNMs. Summarizing the progress and achievements in this field will be of great value to related studies. Herein, based on the different dimensions of CNMs containing 0-dimensional (0D) carbon dots (CDs), fullerenes, 1-dimensional (1D) carbon nanotubes (CNTs) and 2-dimensional (2D) graphene, we introduced the conjugation strategies between DNA and CNMs, their different assembly methods and their applications. In addition, we also discuss the existing challenges and future opportunities in the field.

DNA Origami-Based Protein Manipulation Systems: From Function Regulation to Biological Application.

Proteins directly participate in tremendous physiological processes and mediate a variety of cellular functions. However, precise manipulation of proteins with predefined relative position and stoichiometry for understanding protein-protein interactions and guiding cellular behaviors is still challenging. With superior programmability of DNA molecules, DNA origami technology is able to construct arbitrary nanostructures that can accurately control the arrangement of proteins with various functionalities to solve these problems. Herein, starting from the classification of DNA origami nanostructures and the category of assembled proteins, we summarize the existing DNA origami-based protein manipulation systems (PMSs), review the advances on the regulation of their functions, and discuss their applications in cellular behavior modulation and disease therapy. Moreover, the limitations and potential directions of DNA origami-based PMSs are also presented, which may offer guidance for rational construction and ingenious application.

An incomplete form of anti-ganglioside antibody-positive Miller Fisher syndrome after an Epstein-Barr virus infection: A case report.

RATIONALE: The Miller Fisher syndrome (MFS) is an acute polyradiculoneuritis regarded as an uncommon clinical variant of the Guillain-Barre syndrome (GBS). It is characterized by the clinical triad of ophthalmoplegia, ataxia, and areflexia. The diagnosis of MFS is based on clinical presentation, presence of albuminocytologic dissociation in the cerebrospinal fluid (CSF), and normal brain imaging results. The presence of anti-ganglioside antibodies (GQlb) in the serum is helpful for the diagnosis. A history of upper respiratory tract infection or diarrhea 3 days to 6 weeks before the onset of MFS is common. However, there are some patients with atypical manifestations who are difficult to diagnose. Here, we present an incomplete form of MFS where antibodies against GQ1b were detected in the serum following an Epstein Barr virus (EBV) infection. PATIENT CONCERNS: A 77-year-old Chinese woman was admitted to the hospital with acute diplopia and right blepharoptosis. She had a history of mild upper respiratory tract infection 2 weeks ago. In 1 week, the symptoms rapidly progressed into bilateral ophthalmoplegia and hyporeflexia of the limbs without ataxia. CSF analysis on the third day after onset was normal, without albuminocytologic dissociation. EBV immunoglobulin G (IgG) antibodies were detected in the CSF. GQ1b and GD1b IgG antibodies were positive in the serum and negative in the CSF. No responsible lesion was found on brain imaging examination. DIAGNOSES: In accordance with the progressive bilateral ophthalmoplegia and hyporeflexia, the history of upper respiratory tract infection, the detection of EBV and GQ1b antibodies, and the negative brain imaging examination, the diagnosis of MFS was confirmed. INTERVENTIONS: The patient was administered intravenous immunoglobulin for 5 days. OUTCOMES: She had a favorable outcome after treatment. At the 6-week follow-up, bilateral ocular movement limitation and tendon reflexes had recovered. LESSONS: The diagnosis of MFS can be challenging, especially when encountered with incomplete symptoms and normal CSF results. Attention should be paid to the presence of anti-GQ1b IgG antibodies when the clinical manifestations are incomplete. Furthermore, EBV primary infection could be associated with MFS and considered a potential causative agent.

[Voxel-based analysis of cerebral blood flow changes in Parkinson disease using arterial spin labeling technique].

OBJECTIVE: To explore the imaging biomarker for early diagnosis and disease course monitoring of Parkinson disease (PD) in arterial spin labeling (ASL) technique. METHODS: Between July, 2014 and May, 2017, 23 patients with PD underwent magnetic resonance imaging (MRI) and ASL examinations in our hospital, including 13 in the early stage and 10 in advanced stages. Voxel-based analysis (VBA) was used to observe the regional cerebral blood flow (rCBF) characteristics in PD patients in different stages and three-dimensional continuous arterial spin labeling (3D CASL) was used to analyze the mean cerebral blood flow (mCBF). RESULTS: No significant difference was found in mCBF among PD patients in the early stage, patients in advanced stages and normal control subjects (P=0.30). Compared with the normal control group, the patients with early-stage PD had decreased rCBF in resting state mainly in the right superior occipital gyrus and the right superior frontal gyrus as revealed by VBA (P < 0.001); the patients with advanced PD showed decreased rCBF mainly in the left precentral gyrus and the postcentral gyrus (P < 0.001). The patients with advanced PD exhibited lowered rCBF in the right substantia nigra and the bilateral corpus callosum as compared with the early-stage patients (P < 0.001). CONCLUSIONS: VBA of ASL reveals rCBF alterations in association with the disease progression in PD patients, suggesting that this technique might provide assistance in identification of potential markers for early PD diagnosis and for monitoring the disease course.