Construction of a laser combiner for dual fluorescent single molecule imaging of pRNA of phi29 DNA packaging motor

A customized laser combiner was designed and constructed for dual channel single molecule imaging. The feasibility of a combiner-incorporated imaging system was demonstrated in studies of single molecule FRET. Distance rulers made of dual-labeled dsDNA were used to evaluate the system by determining the distance between one FRET pair. The results showed that the system is sensitive enough to distinguish between distances differing by two base pair and the distances calculated from FRET efficiencies are close to those documented in the literature. The single molecule FRET with the dual-color imaging system was also applied to reconstructed phi29 motor pRNA monomers. Finally, techniques for dual laser alignment and tuning of laser power for dual-color excitation are discussed

Instrumentation and Metrology for Single RNA Counting in Biological Complexes or Nanoparticles by a Single-Molecule Dual-View System

Limited by the spatial resolution of optical microscopy, direct detection or counting of single components in biological complexes or nanoparticles is challenging, especially for RNA, which is conformationally versatile and structurally flexible. We report here the assembly of a customized single-molecule dual-viewing total internal reflection fluorescence imaging system for direct counting of RNA building blocks. The RNA molecules were labeled with a single fluorophore by in vitro transcription in the presence of a fluorescent AMP. Precise calculation of identical or mixed pRNA building blocks of one, two, three, or six copies within the bacteriophage phi29 DNA packaging motor or other complexes was demonstrated by applying a photobleaching assay and evaluated by binomial distribution. The dual-viewing system for excitation and recording at different wavelengths simultaneously will enable the differentiation of different complexes with different labels or relative motion of each labeled component in motion machines

Programmable folding of fusion RNA \u3cem\u3ein vivo\u3c/em\u3e and \u3cem\u3ein vitro\u3c/em\u3e driven by pRNA 3WJ motif of phi29 DNA packaging motor

Misfolding and associated loss of function are common problems in constructing fusion RNA complexes due to changes in energy landscape and the nearest-neighbor principle. Here we report the incorporation and application of the pRNA-3WJ motif of the phi29 DNA packaging motor into fusion RNA with controllable and predictable folding. The motif included three discontinuous ∼18 nucleotide (nt) fragments, displayed a distinct low folding energy (Shu D et al., Nature Nanotechnology, 2011, 6:658–667), and folded spontaneously into a leading core that enabled the correct folding of other functionalities fused to the RNA complex. Three individual fragments dispersed at any location within the sequence allowed the other RNA functional modules to fold into their original structures with authentic functions, as tested by Hepatitis B virus ribozyme, siRNA, and aptamers for malachite green (MG), spinach, and streptavidin (STV). Only nine complementary nucleotides were present for any two of the three ∼18-nt fragments, but the three 9 bp branches were so powerful that they disrupted other double strands with more than 15 bp within the fusion RNA. This system enabled the production of fusion complexes harboring multiple RNA functionalities with correct folding for potential applications in biotechnology, nanomedicine and nanotechnology. We also applied this system to investigate the principles governing the folding of RNA in vivo and in vitro. Temporal production of RNA sequences during in vivo transcription caused RNA to fold into different conformations that could not be predicted with routine principles derived from in vitro studies

RNA Nanoparticle for Treatment of Gastric Cancer

The presently-disclosed subject matter relates to RNA-based composition and method to treat gastric cancer in a subject. More particularly, the presently disclosed subject matter relates to a RNA nanostructure and composition containing a multiple branched RNA nanoparticle, a gastric cancer targeting module, and an effective amount of a therapeutic agent. Further, the presently disclosed subject matter relates to a method of using the RNA nanoparticle composition to treat gastric cancer in a subject having or at risk of having gastric cancer

New Approach to Develop Ultra-High Inhibitory Drug Using the Power Function of the Stoichiometry of the Targeted Nanomachine or Biocomplex

AIMS: To find methods for potent drug development by targeting to biocomplex with high copy number. METHODS: Phi29 DNA packaging motor components with different stoichiometries were used as model to assay virion assembly with Yang Hui\u27s Triangle [Formula: see text], where Z = stoichiometry, M = drugged subunits per biocomplex, p and q are the fraction of drugged and undrugged subunits in the population. RESULTS: Inhibition efficiency follows a power function. When number of drugged subunits to block the function of the complex K = 1, the uninhibited biocomplex equals q(z), demonstrating the multiplicative effect of stoichiometry on inhibition with stoichiometry 1000 \u3e 6 \u3e 1. Complete inhibition of virus replication was found when Z = 6. CONCLUSION: Drug inhibition potency depends on the stoichiometry of the targeted components of the biocomplex or nanomachine. The inhibition effect follows a power function of the stoichiometry of the target biocomplex

L-CAD: Language-based Colorization with Any-level Descriptions using Diffusion Priors

Language-based colorization produces plausible and visually pleasing colors under the guidance of user-friendly natural language descriptions. Previous methods implicitly assume that users provide comprehensive color descriptions for most of the objects in the image, which leads to suboptimal performance. In this paper, we propose a unified model to perform language-based colorization with any-level descriptions. We leverage the pretrained cross-modality generative model for its robust language understanding and rich color priors to handle the inherent ambiguity of any-level descriptions. We further design modules to align with input conditions to preserve local spatial structures and prevent the ghosting effect. With the proposed novel sampling strategy, our model achieves instance-aware colorization in diverse and complex scenarios. Extensive experimental results demonstrate our advantages of effectively handling any-level descriptions and outperforming both language-based and automatic colorization methods. The code and pretrained models are available at: https://github.com/changzheng123/L-CAD

Blood biomarkers for new-onset hypertension in midlife women:a nested case-control study

Objective Midlife in women is associated with an increase in prevalence of hypertension. Little is known on the risk factors of new-onset hypertension among middle-aged women. Methods In this nested case-control study, 1,430 women aged 40 to 60 years with repeated physical examinations between 2009 and 2019 were recruited. Data included age, body mass index, blood pressure (BP), and a series of blood biomarkers. Participants with hypertension were divided into two case-control samples: 388 cases with episodic new-onset hypertension (ie, one normal BP at the first visit and one abnormal BP during follow-up) each with two age-matched controls (n = 776) and 151 cases with regular new-onset hypertension (ie, normal BP at the first two visits and abnormal BP at two or more follow-up visits) each with three age-matched controls (n = 453). Multivariable-adjusted logistic regression was used to analyze the data. Results Our data showed very consistent results for episodic and regular new-onset hypertension, respectively, and verified known associations (odds ratio [95% confidence interval], per SD increase) with obesity (body mass index, 1.72 [1.49-1.98] and 1.81 [1.45-2.26]), inflammation (white blood cell count, 1.39 [1.23-1.58] and 1.38 [1.13-1.69]), and metabolic dysregulation (triglycerides, 1.25 [1.09-1.44] and 1.31 [1.08-1.58]; glucose, 1.46 [1.23-1.73] and 1.27 [1.05-1.54]) but, more surprisingly, also revealed positive associations with red blood cell count (1.27 [1.11-1.44] and 1.38 [1.14-1.68]), hemoglobin (1.18 [1.03-1.35] and 1.31 [1.05-1.64]), and platelet count (1.39 [1.20-1.61] and 1.33 [1.09-1.63]). Conclusions In addition to obesity and metabolic dysregulation, increased hemoglobin and counts of platelets, and red and white blood cells are associated with hypertension in this period. Future study may verify whether these associations are causal in nature and whether these variables are useful in risk stratification.</p

Advances in the Study of Magnesium Alloys and Their Use in Bone Implant Material

Magnesium and magnesium alloys have great application potential in the field of orthopaedics. Compared with traditional inorganic nonmetallic materials and medical polymer materials, magnesium alloys have many advantages, such as better strength, toughness, fatigue resistance, and easy processing. Its mechanical properties are suitable and controllable. It can meet the same elastic modulus, cell compatibility, and biodegradability as human cortical bone. There are also some drawbacks for biodegradability, as magnesium and its alloys, with their high degradation rate, can cause insufficient integrity of the mechanical properties. This paper summarises the research on magnesium and its magnesium alloy materials in the field of bone implantation, looking at what magnesium and its magnesium alloys are, the history of magnesium alloys in bone implant materials, the manufacturing of magnesium alloys, the mechanical properties of magnesium alloys, the bio-compatibility and clinical applications of magnesium alloys, the shortcomings, and the progress of research in recent years