Programming Intracellular Clustering of Spiky Nanoparticles via Liposome Encapsulation

The intracellular clustering of anisotropic nanoparticles is crucial to the improvement of the localized surface plasmon resonance (LSPR) for phototherapy applications. Herein, we programmed the intracellular clustering process of spiky nanoparticles (SNPs) by encapsulating them into an anionic liposome via a frame-guided self-assembly approach. The liposome-encapsulated SNPs (lipo-SNPs) exhibited distinct and enhanced lysosome-triggered aggregation behavior while maintaining excellent monodispersity, even in acidic or protein-rich environments. We explored the enhancement of the photothermal therapy performance for SNPs as a proof of concept. The photothermal conversion efficiency of lipo-SNPs clusters significantly increased 15 times compared to that of single lipo-SNPs. Upon accumulation in lysosomes with a 2.4-fold increase in clustering, lipo-SNPs resulted in an increase in cell-killing efficiency to 45% from 12% at 24 μg/mL. These findings indicated that liposome encapsulation provides a promising approach to programing nanoparticle clustering at the target site, which facilitates advances in the development of smart nanomedicine with programmable enhancement in LSPR.

Immediate application of frozen-thawed embryo transfer cycle in month following COVID-19 infection does not impair subsequent pregnancy outcomes

OBJECTIVES

To investigate whether immediate frozen embryo transfer (FET) in the next month following COVID-19 recovery affects the subsequent pregnancy outcomes.

METHODS

A retrospective cohort study was carried out at a university-affiliated reproductive medicine center. The study group (post-COVID-19 group) consisted of women who were afflicted with COVID-19 in December 2022 and immediately invested in FET in January 2023 after recovery, with embryos transferred and not exposed to the infection. The control group was composed of women treated during the pre-COVID-19 period (January 2019). Multivariable logistic regression analyses as well as a propensity score matching (PSM) approach were introduced to control for the potential confounders and selection bias.

RESULTS

A total of 200 patients were included in the post-COVID-19 group while a total of 641 women were enrolled in the control group. The rate of ongoing pregnancy was comparable between the study cohorts in both the unadjusted and confounder-adjusted logistic regression models. The other reproductive outcomes, including the odds of the positive pregnancy test, implantation, clinical pregnancy, and early pregnancy loss were all similar between the comparison groups. Results from PSM models further confirmed the lack of significant differences in pregnancy outcomes between the post-COVID-19 group versus the control group.

CONCLUSION

Our findings suggested that for patients who get infected with COVID-19, the immediate investment in a FET cycle in the next month after recovery did not seem to compromise the ongoing pregnancy outcomes in cases of transferred embryos resulting from the pre-infection stage. Thus, women who had frozen embryos from the pre-infection cycles should be counseled and encouraged to invest in IVF as soon as possible after recovering from COVID-19 infection. This article is protected by copyright. All rights reserved.

Reconstruction of Vesicle Assemblies with DNA Nanorulers for Resolving Heterogeneity of Vesicles in Live Cells

Nanoscale vesicles such as synaptic vesicles play a pivotal role in efficient interneuronal communications in vivo. However, the coexistence of single vesicle and vesicle clusters in living cells increases the heterogeneity of vesicle populations, which largely complicates the quantitative analysis of the vesicles. The high spatiotemporal monitoring of vesicle assemblies is currently incompletely resolved. Here, this work uses synthetic vesicles and DNA nanorulers to reconstruct in vitro the vesicle assemblies that mimic vesicle clusters in living cells. DNA nanorulers program the lateral distance of vesicle assemblies from 3 to 10 nm. This work uses the carbon fiber nanoelectrode (CFNE) to amperometric monitor artificial vesicle assemblies with sub-10 nm interspaces, and obtain a larger proportion of complex events. This work resolves the heterogeneity of individual vesicle release kinetics in PC12 cells with the temporal resolution down to ≈0.1 ms. This work further analyzes the aggregation state of intracellular vesicles and the exocytosis of living cells with electrochemical vesicle cytometry. The results indicate that the exocytosis of vesicle clusters is critically dependent on the size of clusters. This technology has the potential as a tool to shed light on the heterogeneity analysis of vesicle populations.

Construction of Double-enzyme Complexes with DNA Framework Nanorulers for Improving Enzyme Cascade Catalytic Efficiency

Efficient biocatalytic cascade reactions play a crucial role in guiding intricate, specific and selective intracellular transformation processes. However, the catalytic activity of the enzyme cascade reaction in bulk solution was greatly impacted by the spatial morphology and inter-enzyme distance. The programmability and addressability nature of framework nucleic acid (FNA) allows to be used as scaffold for immobilization and to direct the spatial arrangement of enzyme cascade molecules. Here, we used tetrahedral DNA framework (TDF) as nanorulers to assemble two enzymes for constructing a double-enzyme complex, which significantly enhance the catalytic efficiency of sarcosine oxidase (SOx)/horseradish peroxidase (HRP) cascade system. We synthesized four types of TDF nanorulers capable of programming the lateral distance between enzymes from 5.67 nm to 12.33 nm. Enzymes were chemical modified by ssDNA while preserving most catalytic activity. Polyacrylamide gel electrophoresis (PAGE), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were used to verify the formation of double-enzyme complex. Four types of double-enzyme complexes with different enzyme distance were constructed, in which TDF26 (SOx+HRP) exhibited the highest relative enzyme cascade catalytic activity, ~3.11-fold of free-state enzyme. Importantly, all the double-enzyme complexes demonstrate a substantial improvement in enzyme cascade catalytic activity compared to free enzymes.

Data Storage Using DNA

The exponential growth of global data has outpaced the storage capacities of current technologies, necessitating innovative storage strategies. DNA, as a natural medium for preserving genetic information, has emerged as a highly promising candidate for next-generation storage medium. Storing data in DNA offers several advantages, including ultrahigh physical density and exceptional durability. Facilitated by significant advancements in various technologies, such as DNA synthesis, DNA sequencing, and DNA nanotechnology, remarkable progress has been made in the field of DNA data storage over the past decade. However, several challenges still need to be addressed to realize practical applications of DNA data storage. In this review, the processes and strategies of in vitro DNA data storage are first introduced, highlighting recent advancements. Next, a brief overview of in vivo DNA data storage is provided, with a focus on the various writing strategies developed to date. At last, the challenges encountered in each step of DNA data storage are summarized and promising techniques are discussed that hold great promise in overcoming these obstacles.

GTV Based Automatic Delineation of Clinical Target Volume for Cervical Cancer

PURPOSE/OBJECTIVE(S)

The delineation of gross tumor volume (GTV) and clinical target volume (CTV) are two critical steps in the radiotherapy planning for cervical cancer. GTV defines the primary treatment region for the gross tumor, while CTV is the area surrounding GTV that includes a certain probability (5% to 10%) of subclinical lesions. In contrast to GTV, CTV delineation relies on predefined and judgment-based boundaries, and the high variability among users makes this task particularly challenging. In this study, we evaluated the potential relationship between GTV and CTV and developed an automatic CTV delineation algorithm for cervical cancer based on the fusion of GTV information. We introduced position and shape constraints of GTV to improve the accuracy of CTV delineation.

MATERIALS/METHODS

The GTV-Net deep learning method was used to segment the CTV images of cervical cancer. The method aimed to use the delineation results of the GTV region for one-hot coding and add human anatomy experience in the clinical field to guide the CTV segmentation. This retrospective study included 545 cervical cancer patients who received radiation therapy from June 2017 to May 2019, including postoperative and radical treatment groups. The CTV and GTV regions were manually delineated by human experts. Numerous experiments were conducted to evaluate the performance of the network. First, compared with different network architectures, the Dice similarity coefficient (DSC) and 95% Hausdorff distance (95HD) of GTV-Net were both improved. Then, we compared the GTV-Net method with two resident physicians. Our GTV-Net method outperformed both resident physicians.

RESULTS

In the postoperative group, our method improved the DSC by 4% compared to 3D-UNet, reaching 76.55%, and increased by about 2.57% compared to V-Net's 73.98%, with an improvement of approximately 1.23% compared to the two resident physicians. In the radical treatment group, compared to 3D-UNet's 78.76%, our method increased the DSC by about 3.25%, reaching 82%, and increased by approximately 2.08% compared to V-Net's 79.92%, with an improvement of about 1.35% compared to the two resident physicians. Compared with 3D-UNet, the average 95HD in the postoperative group decreased from 1.489 to 1.457, and in the radical treatment group, it decreased from 1.454 to 1.433. The results of 95HD also showed some improvement compared to V-Net.

CONCLUSION

This study is the first to introduce GTV information for automatic segmentation of the clinical target area for cervical cancer. In this experiment, we observed a positive gain in CTV target automatic delineation guided by GTV information compared to solely performing CTV segmentation, with an improvement in Dice similarity of more than 4% and Hausdorff distance of more than 6% in the experimental dataset. In addition, GTV-guided CTV automatic delineation has also shown promising results on multicenter data, which will better serve the clinical field.

A Multicenter Study on Deep Learning for Glioblastoma Auto-Segmentation with Prior Knowledge in Multimodal Imaging

PURPOSE/OBJECTIVE(S)

A precise radiotherapy plan is required to ensure accurate delineation of gross tumor volumes (GTV) and clinical target volumes (CTV1 and CTV2) of glioblastomas (GBMs). However, traditional manual delineation is labor intensive and highly dependent on oncologists' experience. To construct and evaluate a deep learning-based automatic delineation method using prior knowledge in multimodal medical imaging to automate precise GTV, CTV1 and CTV2 contouring in GBM patients.

MATERIALS/METHODS

We retrospectively collected the CT and MRI scans of 55 eligible patients with histologically proven high-grade glioma (HGG) from an institute, these scans were performed with non-enhanced CT (CT), contrast-enhanced T1-weighted (T1C) and T2-FLAIR (T2F) sequences. We proposed a two-stage automatic segmentation framework (PKMI-Net) for GTV, CTV1 and CTV2 based on deep learning using prior knowledge in multimodal medical imaging, and its segmentation performance was evaluated with dice similarity coefficient (DSC), 95% Harsdorff distance (HD95), average surface distance (ASD) and relative volume difference (RVD). To further investigate the generalizability of our method, we designed and conducted two evaluation strategies (Mix and Cross) on four multicenter datasets (including 55 patients, 37 patients, 21 patients and 35 patients).

RESULTS

The evaluation results with an 11-patient test set from the single institute were summarized in Table 1, the proposed method demonstrated the best accuracy in segmenting, respectively, GTV, CTV1 and CTV, achieving a DSC of 0.94, 0.95 and 0.92; HD95 of 2.07 mm, 1.18 mm and 3.80 mm; ASD of 0.69 mm, 0.39 mm and 1.13 mm and RVE of 5.50%, 3.97% and 9.68%. In the multicenter evaluation, the segmentation performance of our method implemented with the Cross strategy was comparable to that with the Mix strategy, demonstrating that our method had high and stable generalizability across multicenter datasets in automatically segmenting GTV, CTV1 and CTV2.

CONCLUSION

Our proposed method achieved promising results in automatically segmenting gliomas across various datasets, which could improve the quality and efficiency of glioblastoma radiotherapy.

Reproductive history does not compromise subsequent live birth and perinatal outcome following in-vitro fertilization: analysis of 25 329 first frozen-thawed embryo transfer cycles without preimplantation genetic testing for aneuploidy

OBJECTIVE

To investigate the effect of women's reproductive history on live-birth rate and perinatal outcome after first frozen-thawed embryo transfer (FET) without preimplantation genetic testing for aneuploidy.

METHODS

This was a retrospective cohort study of women who had undergone their first FET cycle between January 2014 and December 2020 at a university-affiliated fertility center. No transferred embryo underwent preimplantation genetic testing for aneuploidy. The women were categorized into five groups based on their reproductive history: no previous pregnancy; previous termination of pregnancy (TOP); previous pregnancy loss; previous ectopic pregnancy (EP); and previous live birth. The women with no previous pregnancy were considered as the reference group. The primary outcome was the live-birth rate and secondary endpoints included rates of positive pregnancy test, clinical pregnancy, pregnancy loss and EP as well as perinatal outcomes such as birth weight and preterm birth. Multivariable logistic regression analyses were used to control for a number of potential confounders, including age, body mass index, education level, duration and cause of infertility, insemination method, type of endometrial preparation, number of embryos transferred, embryo developmental stage, quality of the embryos transferred, year of treatment and endometrial thickness. Additionally, propensity score matching (PSM) was used to check the robustness of the main findings.

RESULTS

In total, 25 329 women were included in the final analysis. On univariate analysis, each reproductive-history type except for previous EP was significantly associated with worse pregnancy outcome following in-vitro fertilization (IVF), including rates of positive pregnancy test, clinical pregnancy, pregnancy loss and live birth, when compared with the group of women with no previous pregnancy. However, after correcting for several potential confounders, the differences in rates of live birth, pregnancy loss, positive pregnancy test and clinical pregnancy were no longer significant between the study and control groups on multivariable regression models, while the risk of EP after embryo transfer was elevated among women with a previous TOP or EP. There was no increased risk of adverse perinatal outcome associated with reproductive history compared with the control group. Notably, similar results were obtained from the PSM models, confirming the robustness of the main findings.

CONCLUSION

Relative to women without a previous pregnancy, those with a prior TOP, pregnancy loss, EP or live birth did not have compromised live-birth rate or perinatal outcomes following FET without preimplantation genetic testing for aneuploidy, with the exception of an increased risk of EP in those with prior TOP or EP. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Choroid Plexus Calcification Correlates with Cortical Microglial Activation in Humans: A Multimodal PET, CT, MRI Study

BACKGROUND AND PURPOSE

The choroid plexus (CP) within the brain ventricles is well-known to produce cerebrospinal fluid (CSF). Recently, the CP has been recognized as critical in modulating inflammation. MRI-measured CP enlargement has been reported in neuroinflammatory disorders like MS as well as with aging and neurodegeneration. The basis of MRI-measured CP enlargement is unknown. On the basis of tissue studies demonstrating CP calcification as a common pathology associated with aging and disease, we hypothesized that previously unmeasured CP calcification contributes to MRI-measured CP volume and may be more specifically associated with neuroinflammation.

MATERIALS AND METHODS

We analyzed 60 subjects (43 healthy controls and 17 subjects with Parkinson's disease) who underwent PET/CT using 11C-PK11195, a radiotracer sensitive to the translocator protein expressed by activated microglia. Cortical inflammation was quantified as nondisplaceable binding potential. Choroid plexus calcium was measured via manual tracing on low-dose CT acquired with PET and automatically using a new CT/MRI method. Linear regression assessed the contribution of choroid plexus calcium, age, diagnosis, sex, overall volume of the choroid plexus, and ventricle volume to cortical inflammation.

RESULTS

Fully automated choroid plexus calcium quantification was accurate (intraclass correlation coefficient with manual tracing = .98). Subject age and choroid plexus calcium were the only significant predictors of neuroinflammation.

CONCLUSIONS

Choroid plexus calcification can be accurately and automatically quantified using low-dose CT and MRI. Choroid plexus calcification-but not choroid plexus volume-predicted cortical inflammation. Previously unmeasured choroid plexus calcium may explain recent reports of choroid plexus enlargement in human inflammatory and other diseases. Choroid plexus calcification may be a specific and relatively easily acquired biomarker for neuroinflammation and choroid plexus pathology in humans.

DNA-framework-based multidimensional molecular classifiers for cancer diagnosis

A molecular classification of diseases that accurately reflects clinical behaviour lays the foundation of precision medicine. The development of in silico classifiers coupled with molecular implementation based on DNA reactions marks a key advance in more powerful molecular classification, but it nevertheless remains a challenge to process multiple molecular datatypes. Here we introduce a DNA-encoded molecular classifier that can physically implement the computational classification of multidimensional molecular clinical data. To produce unified electrochemical sensing signals across heterogeneous molecular binding events, we exploit DNA-framework-based programmable atom-like nanoparticles with n valence to develop valence-encoded signal reporters that enable linearity in translating virtually any biomolecular binding events to signal gains. Multidimensional molecular information in computational classification is thus precisely assigned weights for bioanalysis. We demonstrate the implementation of a molecular classifier based on programmable atom-like nanoparticles to perform biomarker panel screening and analyse a panel of six biomarkers across three-dimensional datatypes for a near-deterministic molecular taxonomy of prostate cancer patients.

Nanoparticle Spikes Enhance Cellular Uptake via Regulating Myosin IIA Recruitment

Spike-like nanostructures are omnipresent in natural and artificial systems. Although biorecognition of nanostructures to cellular receptors has been indicated as the primary factor for virus infection pathways, how the spiky morphology of DNA-modified nanoparticles affects their cellular uptake and intracellular fate remains to be explored. Here, we design dually emissive gold nanoparticles with varied spikiness (from 0 to 2) to probe the interactions of spiky nanoparticles with cells. We discovered that nanospikes at the nanoparticle regulated myosin IIA recruitment at the cell membrane during cellular uptake, thereby enhancing cellular uptake efficiency, as revealed by dual-modality (plasmonic and fluorescence) imaging. Furthermore, the spiky nanoparticles also exhibited facilitated endocytosis dynamics, as revealed by real-time dark-field microscopy (DFM) imaging and colorimetry-based classification algorithms. These findings highlight the crucial role of the spiky morphology in regulating the intracellular fate of nanoparticles, which may shed light on engineering theranostic nanocarriers.

Framework Nucleic Acids as Blood-Retinal-Barrier-Penetrable Nanocarrier for Periocular Administration

Designing an ocular drugs delivery system that can permeate the outer blood-retinal barrier (oBRB) is crucial for the microinvasive or noninvasive treatment of ocular fundus diseases. However, due to the lack of a nanocarrier that can maintain structure and composition at the oBRB, only intravitreal injection at the eyeball can deliver therapeutics directly to the ocular fundus via paracellular and intercellular routes, despite the intraocular operations risks. Here, we demonstrated tetrahedral framework nucleic acids (tFNAs) can penetrate the oBRB and deliver therapeutic nucleic acids to the retina of the rat eye in vivo following subconjunctival injection. We also discovered that tFNAs were transported via a paracellular route across the intercellular tight junctions at the oBRB. The histology analysis for ocular layers indicated that individual and aptamer/doxorubicin-loaded tFNAs penetrated all layers of the posterior segment of the eyeball to reach the innermost retina and persisted for over 3 days with minimal systemic biodistribution. We expect that the programmability and penetrability of tFNAs will provide a promising method for drug delivery across oBRB and long-term sustenance at the target site via periocular administration to various tissues.

Mechano-fluorescence actuation in single synaptic vesicles with a DNA framework nanomachine

Biomimetic machines that can convert mechanical actuation to adaptive coloration in a manner analogous to cephalopods have found widespread applications at various length scales. At the nanoscale, a transmutable nanomachine with adaptive colors that can sense and mediate cellular or intracellular interactions is highly desirable. Here, we report the design of a DNA framework nanomachine (DFN) that can autonomously change shape in response to pH variations in single synaptic vesicles, which, in turn, displays adaptive fluorescent colors with a mechano-fluorescence actuation mechanism. To construct a DFN, we used a tetrahedral DNA nanostructure as the framework to incorporate an embedded pH-responsive, i-motif sequence tagged with a Förster resonance energy transfer pair and an affinity cholesterol moiety targeting vesicular membranes. We found that endocytosed DFNs are individually trapped in single endocytic vesicles in living synaptic cells due to the size-exclusion effect. The adaptive fluorescence coloration of DFNs enabled single-vesicle quantification of resting pH values in a processive manner, allowing long-term tracking of the exocytosis and fusion dynamics in intracellular processes and cell-cell communications.

DNA-Based Molecular Machines

Artificial molecular machines have found widespread applications ranging from fundamental studies to biomedicine. More recent advances in exploiting unique physical and chemical properties of DNA have led to the development of DNA-based artificial molecular machines. The unprecedented programmability of DNA provides a powerful means to design complex and sophisticated DNA-based molecular machines that can exert mechanical force or motion to realize complex tasks in a controllable, modular fashion. This Perspective highlights the potential and strategies to construct artificial molecular machines using double-stranded DNA, functional nucleic acids, and DNA frameworks, which enable improved control over reaction pathways and motion behaviors. We also outline the challenges and opportunities of using DNA-based molecular machines for biophysics, biosensing, and biocomputing.

Current diagnosis and potential obstacles for post-neurosurgical bacterial meningitis

Despite the guidance of aseptic technology applied, bacterial meningitis seems to be an unavoidable obstacle in the process of neurosurgery, with high rates of disability and mortality. The diagnosis of post-neurosurgical bacterial meningitis (PNBM) mainly depends both on clinical symptoms and laboratory outcomes. Due to the excessive neuro-inflammatory reactions which are evoked by the primary brain disease or the craniotomy operation, the symptoms derived from the infection and aseptic may not be easily distinguished. On the other hand, the low positive rate and time-consuming character restrict the clinical practical values of bacterial culture. Therefore, it is always difficult to make a definite diagnosis of post-neurosurgical bacterial meningitis. Here, we reviewed the established literature about the diagnostic biomarkers for the PNBM and analyzed the potential obstacles in both clinical and scientific studies. Given the obstacle which has negative impacts on further investigation about the biology of PNBM, we only find relatively small numbers of study on PNBM. In this review, we summarize the established diagnostic methods and biomarkers for PNBM. Meanwhile, we also propose some potential investigation prospects. This review may help to better understand the character of PNBM in both clinical diagnosis and scientific investigations.

Sensitive and high-accuracy detection of Salmonella based on CRISPR/Cas12a combined with recombinase polymerase amplification

Salmonella is a crucial food-borne pathogen causing food poisoning, leading to severe public health events. Here, we developed a technique by integrating recombinase polymerase amplification with CRISPR-LbCas12a and employing two targets with engineered crRNA for detection of Salmonella (RPA-LbCas12a-TTECDS). Our findings revealed that this novel method rapidly detects trace Salmonella in food through fluorescence intensity and provides a template for other food-borne pathogen detection methods. Further, crRNA was optimized to increase detection sensitivity. Double targets were used to enhance the detection accuracy, reaching the level of qPCR, which was superior to fluorescent RPA. The RPA-LbCas12a-TTECDS system specifically detected Salmonella levels as low as 50 CFU per ml at 37°C in 1 h. In summary, a simple, rapid, sensitive and high accuracy detection technique based on CRISPR-Cas12a was created for Salmonella detection without complicated equipment.

DNA origami nanocalipers for pH sensing at the nanoscale

A DNA origami nanocaliper is employed as a shape-resolved nanomechanical device, with pH-responsive triplex DNA integrated into the two arms. The shape transition of the nanocaliper results in a subtle difference depending on the local pH that is visible via TEM imaging, demonstrating the potential of these nanocalipers to act as a universal platform for pH sensing at the nanoscale.

Reconstructing Soma-Soma Synapse-like Vesicular Exocytosis with DNA Origami

Cell-cell communications exhibit distinct physiological functions in immune responses and neurotransmitter signaling. Nevertheless, the ability to reconstruct a soma-soma synapse-like junction for probing intercellular communications remains difficult. In this work, we develop a DNA origami nanostructure-based method for establishing cell conjugation, which consequently facilitates the reconstruction of a soma-soma synapse-like junction. We demonstrate that intercellular communications including small molecule and membrane vesicle exchange between cells are maintained in the artificially designed synapse-like junction. By inserting the carbon fiber nanometric electrodes into the soma-soma synapse-like junction, we accomplish the real-time monitoring of individual vesicular exocytotic events and obtain the information on vesicular exocytosis kinetics via analyzing the parameters of current spikes. This strategy provides a versatile platform to study synaptic communications.

Nucleic Acid Tests for Clinical Translation

Nucleic acids, including deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), are natural biopolymers composed of nucleotides that store, transmit, and express genetic information. Overexpressed or underexpressed as well as mutated nucleic acids have been implicated in many diseases. Therefore, nucleic acid tests (NATs) are extremely important. Inspired by intracellular DNA replication and RNA transcription, in vitro NATs have been extensively developed to improve the detection specificity, sensitivity, and simplicity. The principles of NATs can be in general classified into three categories: nucleic acid hybridization, thermal-cycle or isothermal amplification, and signal amplification. Driven by pressing needs in clinical diagnosis and prevention of infectious diseases, NATs have evolved to be a rapidly advancing field. During the past ten years, an explosive increase of research interest in both basic research and clinical translation has been witnessed. In this review, we aim to provide comprehensive coverage of the progress to analyze nucleic acids, use nucleic acids as recognition probes, construct detection devices based on nucleic acids, and utilize nucleic acids in clinical diagnosis and other important fields. We also discuss the new frontiers in the field and the challenges to be addressed.

Dupilumab reduces systemic corticosteroid use and sinonasal surgery rate in CRSwNP

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a type 2 inflammatory disease with a high symptom burden and poor quality of life. Treatment options include recurrent surgeries and/or frequent systemic corticosteroids (SCS). Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin-4 and interleukin-13, key drivers of type 2-mediated inflammation. We report results of pooled analyses from 2 randomised, double-blind, placebo-controlled phase 3 studies (SINUS 24 [NCT02912468]; SINUS-52 [NCT02898454]) to evaluate dupilumab effect versus placebo in adults with CRSwNP with/without SCS use and sinonasal surgery.

METHODOLOGY

SINUS-24 patients were randomised 1:1 to subcutaneous dupilumab 300 mg (n=143) or placebo (n=133) every 2 weeks (q2w) for 24 weeks. SINUS-52 patients were randomised 1:1:1 to 52 weeks of subcutaneous dupilumab 300 mg q2w (n=150), 24 weeks q2w followed by 28 weeks of dupilumab 300 mg every 4 weeks (n=145) or 52 weeks of placebo q2w (n=153).

RESULTS

Dupilumab reduced the number of patients undergoing sinonasal surgery (82.6%), the need for in-study SCS use (73.9%), and SCS courses (75.3%). Significant improvements were observed with dupilumab vs placebo regardless of prior sinonasal surgery or SCS use in nasal polyp, nasal congestion, Lund-MacKay, and Sinonasal Outcome Test (22-items) scores, and the University of Pennsylvania Smell Identification Test.

CONCLUSIONS

Dupilumab demonstrated significant improvements in disease signs and symptoms and reduced the need for sino-nasal surgery and SCS use versus placebo in patients with severe CRSwNP, regardless of SCS use in the previous 2 years, or prior sinonasal surgery.

Programming folding cooperativity of the dimeric i-motif with DNA frameworks for sensing small pH variations

The response sensitivity of a molecular sensor is determined by the folding cooperativity of its responsive module. Using an H⁺-responsive dimeric DNA i-motif as a model, we demonstrate the enhancement of its folding cooperativity through preorganization by a DNA framework, and with it we fabricate robust intracellular pH sensors with high response sensitivity.

[Effects of vestibular spontaneous nystagmus on visual smooth pursuit function]

Objective: The aim of the study is to analyze the effects of vestibular spontaneous nystagmus(SN) on the smooth pursuit function of visual ocularmotor system. Methods: A total of 46 patients with acute unilateral peripheral vestibular syndrome with SN (26 cases of vestibular neuritis, 6 cases of Ramsay Hunt Syndrome (RHS) with vertigo, 14 cases of sudden deafness with vertigo) were included in this work. In the study group, the results of SPT and SN test with videonystagmography(VNG) were also reviewed. Taking SPT parameters, the influence of SN intensity on SPT gain, asymmetry and waveform and their correlation were analyzed.SPSS19.0 software was used for statistical analysis. Results: Among the 46 patients, there were 36 cases of SN pointing to the healthy side(SN intensity range of 2.68°/s-32.53°/s), and 10 cases of SN pointing to the affected side (SN intensity range of 2.66°/s-16.54°/s). SN intensity was divided into 3 groups, including light(0.50°/s-5.00°/s), medium(5.01°/s-10.00°/s) and strong(>10.01°/s), accounting for 14 cases(30.4%), 18 cases(39.1%) and 14 cases(30.4%), respectively. The differences of the gain of SPT to the fast phase and slow phase direction in the overall groups and light, medium and strong groups of SN intensity respectively were statistically significant(t_total=13.338, t_light=6.184, t_medium=8.436, t_strong=8.477, all of P<0.001). The difference of SPT gain in SN fast phase direction between groups with different SN intensity was statistically significant(F=9.639, P<0.001),there was no statistically significant difference in SPT gain between the groups on the SN slow phase direction(F=1.137, P=0.330).The SN intensity significantly negatively correlated with the SPT gain of the fast phase direction of SN (r=-0.433, P=0.003), that was, the SPT gain on the fast phase direction of SN decreased with the increase of SN intensity. There was no significant correlation between SN intensity and the gain of SPT on the slow phase direction of SN (r=-0.061, P=0.687). SPT waveform analysis showed that type I, type II and type III accounted for 8 cases(17.4%), 21 cases(45.6%) and 17 cases(37.0%), respectively. The corresponding mean values of SN intensity were (3.71±0.69)°/s, (7.44±1.88)°/s, (20.04±5.53)°/s, respectively, without type IV wave. The intensity of SN was positively correlated with the asymmetric value of the gain of SPT left and right(r=0.450,P=0.002). That was, with the increase of SN strength, the asymmetric value also increased, and the worse the asymmetry of the gain of SPT left and right pursuit was, the worse the SPT waveform was. Conclusion: SPT gain, asymmetry and SPT waveforms are all affected by SN, and the greater the intensity of SN, the greater the influence on the three. When SN is strong, type III waves may occur, suggesting that acute peripheral vestibular syndrome can also affect the visual ocularmotor systems.

Tracking endocytosis and intracellular distribution of spherical nucleic acids with correlative single-cell imaging

A comprehensive understanding of interactions between nanoparticles (NPs) and biological components is critical to the clinical application of NPs and nanomedicine. Here we provide a step-by-step correlative imaging approach to investigate plasmonic NPs of different aggregation states at the single-cell level. Traceable spherical nucleic acids (SNAs) are fabricated by decorating 50-nm spherical gold NPs with fluorophore-labeled DNA, serving as dually emissive (fluorescent and plasmonic) NPs. The in situ correlative imaging with dark-field microscopy (DFM) and fluorescence microscopy (FM) reveals intracellular distribution of SNAs, whereas DFM combined with scanning electron microscopy (SEM) allows semi-quantification of SNA clustering states in solution. The imaging data are analyzed by ImageJ and a colorimetry-based algorithm written in Python. The clustering states of SNAs in a single cell can be efficiently distinguished within 20 s. This method can be readily installed to monitor real-time endocytosis and cellular distribution of plasmonic NPs of different aggregation states and to quantitatively image targets of interest (e.g., specific DNA, messenger RNA, peptides or proteins) in living cells. The entire procedure can be completed in 3-5 d and requires standard DFM, FM and SEM imaging and data analysis skills and equipment.

Nucleic Acids Analysis

Nucleic acids are natural biopolymers of nucleotides that store, encode, transmit and express genetic information, which play central roles in diverse cellular events and diseases in living things. The analysis of nucleic acids and nucleic acids-based analysis have been widely applied in biological studies, clinical diagnosis, environmental analysis, food safety and forensic analysis. During the past decades, the field of nucleic acids analysis has been rapidly advancing with many technological breakthroughs. In this review, we focus on the methods developed for analyzing nucleic acids, nucleic acids-based analysis, device for nucleic acids analysis, and applications of nucleic acids analysis. The representative strategies for the development of new nucleic acids analysis in this field are summarized, and key advantages and possible limitations are discussed. Finally, a brief perspective on existing challenges and further research development is provided.

Novel variants and uncommon cases among southern Chinese children with X-linked hypophosphatemia

PURPOSE

X-linked hypophosphatemia (XLH) is the most common inherited renal phosphate wasting disorder and is often misdiagnosed as vitamin D deficiency. This study aims to provide clinical and mutational characteristics of 65 XLH pediatric patients in southern China.

METHODS

In this work, a combination of DNA sequencing and qPCR analysis was used to study the PHEX gene in 80 pediatric patients diagnosed with hypophosphatemia. The clinical and laboratory data of confirmed 65 XLH patients were assessed and analyzed retrospectively.

RESULTS

In 65 XLH patients from 61 families, 51 different variants in the PHEX gene were identified, including 23 previously reported variants and 28 novel variants. In this cohort of XLH patients, the c.1601C>T(p.Pro534Leu) variant appears more frequently. Fourteen uncommon XLH cases were described, including four boys with de novo mosaic variants, eight patients with large deletions and a pair of monozygotic twins. The clinical manifestations in this cohort are very similar to those previously reported.

CONCLUSION

This study extends the mutational spectrum of the PHEX gene, which will contribute to accurate diagnosis. This study also suggests a supplementary qPCR or MLPA assay may be performed along with classical sequencing to confirm the gross insertion/deletion.

Effect of bradykinin on rats with thromboangiitis obliterans through PI3K/Akt signaling pathway

OBJECTIVE

To explore the effect of bradykinin on rats with thromboangiitis obliterans (TAO) through the phosphatidylinositol 3-hydroxy kinase/protein kinase B (PI3K/Akt) signaling pathway.

MATERIALS AND METHODS

The female Wistar rats were injected with lauric acid via the femoral artery to establish the TAO model, and they were randomly divided into control group (healthy rats), model group (TAO rats) and bradykinin group (TAO rats injected with bradykinin B2 receptor-specific inhibitor). The control was set in each group before the operation. The level of serum bradykinin in each group was detected via enzyme-linked immunosorbent assay (ELISA), and the reactive oxygen species (ROS) level, Caspase-3 activity and PI3K/Akt protein concentration in vascular tissues were measured via ELISA, Western blotting, ROS assay, and Caspase-3 activity assay, respectively. Moreover, the specific therapeutic mechanism of bradykinin was analyzed.

RESULTS

In control group, the intima of the lower extremity venous tissues was smooth, the extima had no evident changes, and there was no inflammatory cell invasion around the arteries and veins. In model group, there was massive inflammatory cell invasion into the lower extremity venous tissues. In bradykinin group, fibrosis and atrophy occurred in venous tissues, the extima was thickened without fibrosis, and there was phagocytosis of neutrophils and mononuclear macrophages around the arteries and veins, as well as massive inflammatory infiltration. The PI3K/Akt protein concentration in lower extremity venous tissues was the highest in control group and the lowest in bradykinin group, and there were statistically significant differences (p<0.01). At 24 h after administration of doxorubicin (DOX), the level of ROS in lower extremity venous tissues was higher in bradykinin group than that in model group (p<0.05), and it was also higher in model group than that in control group (p<0.05). Besides, the activity of Caspase-3 in lower extremity venous tissues was significantly increased in bradykinin group compared with that in model group and control group, while it was slightly higher in model group than that in control group (p<0.05).

CONCLUSIONS

The low expression of bradykinin can promote TAO in rats by the mechanism that it inhibits the PI3K/Akt signaling pathway to raise the oxidative stress level, thereby aggravating TAO.

Programming Biomimetically Confined Aptamers with DNA Frameworks

Active sites of proteins are generally encapsulated within three-dimensional peptide scaffolds that provide the molecular-scale confinement microenvironment. Nevertheless, the ability to tune thermodynamic stability in biomimetic molecular confinement relies on the macromolecular crowding effect of lack of stoichiometry and reconfigurability. Here, we report a framework nucleic acid (FNA)-based strategy to increase thermodynamic stability of aptamers. We demonstrate that the molecular-scale confinement increases the thermodynamic stability of aptamers via facilitated folding kinetics, which is confirmed by the single-molecule FRET (smFRET). Unfavorable conformations of aptamers are restricted as revealed by the Monte Carlo simulation. The binding affinity of the DNA framework-confined aptamer is improved by ∼3-fold. With a similar strategy we improve the catalytic activity of hemin-binding aptamer. Our approach thus shows high potential for designing protein-mimicking DNA nanostructures with enhanced binding affinity and catalytic activity for biosensing and biomedical engineering.

Encapsulation and release of living tumor cells using hydrogels with the hybridization chain reaction

Circulating tumor cells (CTCs) enable noninvasive liquid biopsy and identification of cancer. Various approaches exist for the capture and release of CTCs, including microfluidic methods and those involving magnetic beads or nanostructured solid interfaces. However, the concomitant cell damage and fragmentation that often occur during capture make it difficult to extensively characterize and analyze living CTCs. Here, we describe an aptamer-trigger-clamped hybridization chain reaction (atcHCR) method for the capture of CTCs by porous 3D DNA hydrogels. The 3D environment of the DNA networks minimizes cell damage, and the CTCs can subsequently be released for live-cell analysis. In this protocol, initiator DNAs with aptamer-toehold biblocks specifically bind to the epithelial cell adhesion molecule (EpCAM) on the surface of CTCs, which triggers the atcHCR and the formation of a DNA hydrogel. The DNA hydrogel cloaks the CTCs, facilitating quantification with minimal cell damage. This method can be used to quantitively identify as few as 10 MCF-7 cells in a 2-µL blood sample. Decloaking of tumor cells via gentle chemical stimulus (ATP) is used to release living tumor cells for subsequent cell culture and live-cell analysis. We also describe how to use the protocol to encapsulate and release cells of cancer cell lines, which can be used in preliminary experiments to model CTCs. The whole protocol takes ~2.5 d to complete, including downstream cell culture and analysis.

Ultrafast DNA Sensors with DNA Framework-Bridged Hybridization Reactions

Intracellular DNA-based hybridization reactions generally occur under tension rather than in free states, which are spatiotemporally controlled in physiological conditions. However, how nanomechanical forces affect DNA hybridization efficiencies in in-vitro DNA assays, for example, biosensors or biochips, remains largely elusive. Here, we design DNA framework-based nanomechanical handles that can control the stretching states of DNA molecules. Using a pair of tetrahedral DNA framework (TDF) nanostructured handles, we develop bridge DNA sensors that can capture target DNA with ultrafast speed and high efficiency. We find that the rigid TDF handles bind two ends of a single-stranded DNA (ssDNA) and hold it in a stretched state, with an apparent stretching length comparable to its counterpart of double-stranded DNA (dsDNA) via atomic force microscopy measurement. The DNA stretching effect of ssDNA is then monitored using single-molecule fluorescence energy transfer (FRET), resulting in decreased FRET efficiency in the stretched ssDNA. By controlling the stretching state of ssDNA, we obtained significantly improved hybridization kinetics (within 1 min) and hybridization efficiency (∼98%) under the target concentration of 500 nM. The bridge DNA sensors demonstrated high sensitivity (1 fM), high specificity (single mismatch mutation discrimination), and high selectivity (suitable for the detection in serum and blood) under the target concentration of 10 nM. Controlling the stretching state of ssDNA shows great potential in biosensors, bioimaging, and biochips applications.

Deformation-Resistant, Double-Layer DNA Self-Assembled Nanoraft with High Positioning Precision

The precise control and localization of a single entity on a stiff and rigid interface are crucial for exploring interentity interactions. A critical challenge for the precise positioning of a single entity on a substrate lies in how to construct a solid and flat interface with high positioning precision. Herein, we developed a solid DNA self-assembled nanoraft with high conformational stability by constructing a double-layer DNA origami. Compared with conventional single-layer DNA origami, the double-layer nanoraft showed higher deformation resistance capability with the nanorafts possessing higher structural integrity. Further, we analyzed the deformability of these two DNA origamis by structural reconstruction simulation, the results of which were significantly consistent with transmission electron microscopy experimental results. Using the deformation-resistant DNA self-assembled nanoraft, we achieved the precise positioning of single-stranded DNA probes on the DNA nanointerface by visualizing the AuNPs captured by the probes. Compared with the interface constructed by single-layer DNA origami, the distance between AuNPs on the two-layer DNA origami was more approximate to the theoretical value that we designed. The rigid nanointerface with high deformation resistance capability thus provides a powerful means for facilitating the self-assembly of heterogeneous elements with precisely controlled spacing and position.

DNA Framework-Based Topological Cell Sorters

Molecular recognition in cell biological process is characterized with specific locks-and-keys interactions between ligands and receptors, which are ubiquitously distributed on cell membrane with topological clustering. Few topologically-engineered ligand systems enable the exploration of the binding strength between ligand-receptor topological organization. Herein, we generate topologically controlled ligands by developing a family of tetrahedral DNA frameworks (TDFs), so the multiple ligands are stoichiometrically and topologically arranged. This topological control of multiple ligands changes the nature of the molecular recognition by inducing the receptor clustering, so the binding strength is significantly improved (ca. 10-fold). The precise engineering of topological complexes formed by the TDFs are readily translated into effective binding control for cell patterning and binding strength control of cells for cell sorting. This work paves the way for the development of versatile design of topological ligands.

The solar nebula origin of (486958) Arrokoth, a primordial contact binary in the Kuiper Belt

The New Horizons spacecraft's encounter with the cold classical Kuiper Belt object (486958) Arrokoth (provisional designation 2014 MU₆₉) revealed a contact-binary planetesimal. We investigated how Arrokoth formed and found that it is the product of a gentle, low-speed merger in the early Solar System. Its two lenticular lobes suggest low-velocity accumulation of numerous smaller planetesimals within a gravitationally collapsing cloud of solid particles. The geometric alignment of the lobes indicates that they were a co-orbiting binary that experienced angular momentum loss and subsequent merger, possibly because of dynamical friction and collisions within the cloud or later gas drag. Arrokoth's contact-binary shape was preserved by the benign dynamical and collisional environment of the cold classical Kuiper Belt and therefore informs the accretion processes that operated in the early Solar System.

Automated Nanoplasmonic Analysis of Spherical Nucleic Acids Clusters in Single Cells

Spherical nucleic acids (SNAs) have been extensively used in the field of biosensing, drug delivery, and theranostics. Precise engineering of SNAs and their clinical application require better understanding of their cellular internalization process. We demonstrate a colorimetry-based algorithm that can analyze the aggregation states of SNAs clusters on the basis of the changes of plasmonic colors of SNAs. The dark-field microscopy (DFM) images of cytoplasmic region of single cells are imported as raw data. All the image spots are analyzed in the interference reduction process, and the clustering states of target image spots are assigned on the basis of the distribution of coordinates of all the pixels in the CIE map. This method provides faster analysis on clustering states of extracellular and intracellular SNAs with good accuracy. Moreover, the clustering states of SNAs in 20 single cells (generally >1000) can be efficiently distinguished within 200 s. Therefore, our method provides an automatic, quantitative, objective, and repeatable way to analyze SNAs aggregations, and shows good application potential in robust and quantitative nanoplasmonic analysis in single cells.

FeSe quantum dots for in vivo multiphoton biomedical imaging

An immense demand in biomedical imaging is to develop efficient photoluminescent probes with high biocompatibility and quantum yield, as well as multiphoton absorption performance to improve penetration depth and spatial resolution. Here, iron selenide (FeSe) quantum dots (QDs) are reported to meet these criteria. The synthesized QDs exhibit two- and three-photon excitation property at 800- and 1080-nm wavelengths and high quantum yield (ca. 40%), which are suitable for second-window imaging. To verify their biosuitability, poly(ethylene glycol)-conjugated QDs were linked with human epidermal growth factor receptor 2 (HER2) antibodies for in vitro/in vivo two-photon imaging in HER2-overexpressed MCF7 cells and a xenograft breast tumor model in mice. Imaging was successfully carried out at a depth of up to 500 μm from the skin using a nonlinear femtosecond laser at an excitation wavelength of 800 nm. These findings may open up a way to apply biocompatible FeSe QDs to multiphoton cancer imaging.

DNA Framework-Programmed Cell Capture via Topology-Engineered Receptor-Ligand Interactions

Receptor-ligand interactions (RLIs) that play pivotal roles in living organisms are often depicted with the classic keys-and-locks model. Nevertheless, RLIs on the cell surface are generally highly complex and nonlinear, partially due to the noncontinuous and dynamic distribution of receptors on extracellular membranes. Here, we develop a tetrahedral DNA framework (TDF)-programmed approach to topologically engineer RLIs on the cell membrane, which enables active recruitment-binding of clustered receptors for high-affinity capture of circulating tumor cells (CTCs). The four vertices of a TDF afford orthogonal anchoring of ligands with spatial organization, based on which we synthesized n-simplexes harboring 1-3 aptamers targeting epithelial cell adhesion molecule (EpCAM) that are overexpressed on the membrane of tumor cells. The 2-simplex with three aptamers not only shows increased binding affinity (∼19-fold) but prevents endocytosis by cells. By using 2-simplex as the capture probe, we demonstrate the high-efficiency CTC capture, which is challenged in real clinical breast cancer patient samples. This TDF-programmed platform thus provides a powerful means for studying RLIs in physiological settings and for cancer diagnosis.