Effect of respiratory muscle training in patients with stable chronic obstructive pulmonary disease: A systematic review and meta-analysis.

Objectives: Chronic obstructive pulmonary disease (COPD) is a prevalent respiratory disorder characterized by progressive airflow limitation. This meta-analysis aims to evaluate the effectiveness of respiratory muscle training (RMT) on key pulmonary function parameters, inspiratory muscle strength and quality of life in patients with stable COPD. Methods: A comprehensive search was conducted in the databases including PubMed, Cochrane, Web of Science, Embase, and ClinicalTrials.gov, from their inception to June 12, 2023. Randomized controlled trials (RCTs) evaluating the impact of RMT on stable COPD were included for meta-analysis. Results: In total, 12 RCTs involving 453 participants were included in the meta-analysis. RMT demonstrated a significant increase in maximal inspiratory pressure (PImax, MD, 95% CI: 14.34, 8.17 to 20.51, P < 0.001) but not on maximal expiratory pressure (PEmax). No significant improvement was observed in 6-Min walk test (6MWT), dyspnea, forced expiratory volume in 1 s (FEV1), forced vital capacity ratio (FVC) and quality of life between RMT and control groups. However, subgroup analysis revealed a significant negative effect of RMT alone on FEV1/FVC (MD, 95% CI: 2.59, -5.11 to -0.06, P = 0.04). When RMT was combined with other interventions, improvements in FEV1/FVC and FEV1 were found, although not statistically significant. Conclusion: RMT can effectively improve maximal inspiratory pressure in stable COPD patients, but the effect is slight in improving lung function, dyspnea and quality of life. It is recommended to combine with other treatment strategies to comprehensively improve the prognosis of COPD patients.

Chemical Patterning on Nanocarbons: Functionality Typewriting.

Nanocarbon materials have become extraordinarily compelling for their significant potential in the cutting-edge science and technology. These materials exhibit exceptional physicochemical properties due to their distinctive low-dimensional structures and tailored surface characteristics. An attractive direction at the forefront of this field involves the spatially resolved chemical functionalization of a diverse range of nanocarbons, encompassing carbon nanotubes, graphene, and a myriad of derivative structures. In tandem with the technological leaps in lithography, these endeavors have fostered the creation of a novel class of nanocarbon materials with finely tunable physical and chemical attributes, and programmable multi-functionalities, paving the way for new applications in fields such as nanoelectronics, sensing, photonics, and quantum technologies. Our review examines the swift and dynamic advancements in nanocarbon chemical patterning. Key breakthroughs and future opportunities are highlighted. This review not only provides an in-depth understanding of this fast-paced field but also helps to catalyze the rational design of advanced next-generation nanocarbon-based materials and devices.

Functional PDMS Elastomers: Bulk Composites, Surface Engineering, and Precision Fabrication.

Polydimethylsiloxane (PDMS)-the simplest and most common silicone compound-exemplifies the central characteristics of its class and has attracted tremendous research attention. The development of PDMS-based materials is a vivid reflection of the modern industry. In recent years, PDMS has stood out as the material of choice for various emerging technologies. The rapid improvement in bulk modification strategies and multifunctional surfaces has enabled a whole new generation of PDMS-based materials and devices, facilitating, and even transforming enormous applications, including flexible electronics, superwetting surfaces, soft actuators, wearable and implantable sensors, biomedicals, and autonomous robotics. This paper reviews the latest advances in the field of PDMS-based functional materials, with a focus on the added functionality and their use as programmable materials for smart devices. Recent breakthroughs regarding instant crosslinking and additive manufacturing are featured, and exciting opportunities for future research are highlighted. This review provides a quick entrance to this rapidly evolving field and will help guide the rational design of next-generation soft materials and devices.

Superparamagnetic Nanocrystals Clustered Using Poly(ethylene glycol)-Crosslinked Amphiphilic Copolymers for the Diagnosis of Liver Cancer.

Superparamagnetic iron oxide (SPIO) nanocrystals have been extensively studied as theranostic nanoparticles to increase transverse (T2) relaxivity and enhance contrast in magnetic resonance imaging (MRI). To improve the blood circulation time and enhance the diagnostic sensitivity of MRI contrast agents, we developed an amphiphilic copolymer, PCPZL, to effectively encapsulate SPIO nanocrystals. PCPZL was synthesized by crosslinking a polyethylene glycol (PEG)-based homobifunctional linker with a hydrophobic star-like poly(ε-benzyloxycarbonyl-L-lysine) segment. Consequently, it could self-assemble into shell-crosslinked micelles with enhanced colloidal stability in bloodstream circulation. Notably, PCPZL could effectively load SPIO nanocrystals with a high loading capacity of 66.0 ± 0.9%, forming SPIO nanoclusters with a diameter of approximately 100 nm, a high cluster density, and an impressive T2 relaxivity value 5.5 times higher than that of Resovist®. In vivo MRI measurements highlighted the rapid accumulation and contrast effects of SPIO-loaded PCPZL micelles in the livers of both healthy mice and nude mice with an orthotopic hepatocellular carcinoma tumor model. Moreover, the magnetic micelles remarkably enhanced the relative MRI signal difference between the tumor and normal liver tissues. Overall, our findings demonstrate that PCPZL significantly improves the stability and magnetic properties of SPIO nanocrystals, making SPIO-loaded PCPZL micelles promising MRI contrast agents for diagnosing liver diseases and cancers.

Rational Structural Design of Polymer Pens for Energy-Efficient Photoactuation.

Photoactuated pens have emerged as promising tools for expedient, mask-free, and versatile nanomanufacturing. However, the challenge of effectively controlling individual pens in large arrays for high-throughput patterning has been a significant hurdle. In this study, we introduce novel generations of photoactuated pens and explore the impact of pen architecture on photoactuation efficiency and crosstalk through simulations and experiments. By introducing a thermal insulating layer and incorporating an air ap in the architecture design, we have achieved the separation of pens into independent units. This new design allowed for improved control over the actuation behavior of individual pens, markedly reducing the influence of neighboring pens. The results of our research suggest novel applications of photoactive composite films as advanced actuators across diverse fields, including lithography, adaptive optics, and soft robotics.

Role of ferroptosis in fibrosis diseases.

Ferroptosis is a pervasive non-apoptotic mode of cell death that is different from autophagy or necrosis. It is mainly caused by an imbalance between the production and degradation of lipid reactive oxygen species in cells. Several metabolic pathways and biochemical processes, such as amino acid and lipid metabolism, iron handling, and mitochondrial respiration, affect and regulate cell sensitivity to peroxidation and ferroptosis. Organ fibrosis, a pathological manifestation of several etiological conditions, leads to chronic tissue injury and is characterized by excessive deposition of extracellular matrix components. Excessive tissue fibrosis can have diverse pathophysiological effects on several organ systems, eventually causing organ dysfunction and failure. The current manuscript provides a review that illustrates the link between ferroptosis and organ fibrosis and to better understand the underlying mechanisms. It provides novel potential therapeutic approaches and targets for fibrosis diseases.

The alcohol extracts of Sceptridium ternatum (Thunb.) Lyon exert anti-pulmonary fibrosis effect through targeting SETDB1/STAT3/p-STAT3 signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: Pulmonary fibrosis (PF) is a pathological process of irreversible scarring of lung tissues, with limited treatment means. Sceptridium ternatum (Thunb.) Lyon (STE) is a traditional Chinese herbal medicine that has a traditional use in relieving cough and asthma, resolving phlegm, clearing heat, and detoxicating in China. However, its role in PF has not been reported. AIM OF THE STUDY: This study aims to investigate the protective role of STE in PF and the underlying mechanisms. MATERIALS AND METHODS: Sprague-Dawley (SD) rats were divided into control group, PF model group, positive drug (pirfenidone) group and STE group. After 28 days of STE administration in bleomycin (BLM)-induced PF rats, living Nuclear Magnetic Resonance Imaging (NMRI) was used to observe the structural changes of lung tissues. H&E and Masson's trichrome staining were used to observe PF-associated pathological alteration, and immunohistochemistry (IHC) staining, western blotting, and qRT-PCR were used to detect the expression of PF-related marker proteins in the lung tissues. ELISA was used to detect PF-associated biochemical criteria in the lung tissue homogenates. The proteomics technology was used to screen the different proteins. Co-immunoprecipitation, western blotting, and IHC staining were used to confirm the underlying targets of STE as well as its downstream signaling. UPLC-Triple-TOF/MS assay was used to explore the effective components in the alcohol extracts of STE. Autodock vina was used to detect the potential binding between the above effective components and SETDB1. RESULTS: STE prevented PF by inhibiting the activation of lung fibroblasts and ECM deposition in BLM-induced PF rats. Mechanism analyses demonstrated that STE could inhibit the up-regulation of SETDB1 induced by BLM and TGF-ß1, which further blocked the binding of SETDB1 and STAT3 as well as the phosphorylation of STAT3, ultimately preventing the activation and proliferation of lung fibroblasts. CONCLUSION: STE played a preventive role in PF by targeting the SETBD1/STAT3/p-STAT3 pathway, which may be a potential therapeutic agent for PF.

SOX17 is a Critical Factor in Maintaining Endothelial Function in Pulmonary Hypertension by an Exosome-Mediated Autocrine Manner.

Endothelial dysfunction is considered a predominant driver for pulmonary vascular remodeling in pulmonary hypertension (PH). SOX17, a key regulator of vascular homoeostasis, has been found to harbor mutations in PH patients, which are associated with PH susceptibility. Here, this study explores whether SOX17 mediates the autocrine activity of pulmonary artery ECs to maintain endothelial function and vascular homeostasis in PH and its underlying mechanism. It is found that SOX17 expression is downregulated in the endothelium of remodeled pulmonary arteries in IPH patients and SU5416/hypoxia (Su/hypo)-induced PH mice as well as dysfunctional HPAECs. Endothelial knockdown of SOX17 accelerates the progression of Su/hypo-induced PH in mice. SOX17 overexpression in the pulmonary endothelium of mice attenuates Su/hypo-induced PH. SOX17-associated exosomes block the proliferation, apoptosis, and inflammation of HPAECs, preventing pulmonary arterial remodeling and Su/hypo-induced PH. Mechanistic analyses demonstrates that overexpressing SOX17 promotes the exosome-mediated release of miR-224-5p and miR-361-3p, which are internalized by injured HPAECs in an autocrine manner, ultimately repressing the upregulation of NR4A3 and PCSK9 genes and improving endothelial function. These results suggest that SOX17 is a key gene in maintaining endothelial function and vascular homeostasis in PH through regulating exosomal miRNAs in an autocrine manner.

Localized Photoactuation of Polymer Pens for Nanolithography.

Localized actuation is an important goal of nanotechnology broadly impacting applications such as programmable materials, soft robotics, and nanolithography. Despite significant recent advances, actuation with high temporal and spatial resolution remains challenging to achieve. Herein, we demonstrate strongly localized photoactuation of polymer pens made of polydimethylsiloxane (PDMS) and surface-functionalized short carbon nanotubes based on a fundamental understanding of the nanocomposite chemistry and device innovations in directing intense light with digital micromirrors to microscale domains. We show that local illumination can drive a small group of pens (3 × 3 over 170 µm × 170 µm) within a massively two-dimensional array to attain an out-of-plane motion by more than 7 µm for active molecular printing. The observed effect marks a striking three-order-of-magnitude improvement over the state of the art and suggests new opportunities for active actuation.

Hippocampal atrophy in neurofunctional subfields in insomnia individuals.

Objective: The aim of this study was to investigate the pattern of volume changes in neurofunctional hippocampal subfields in patients with insomnia and their associations with risk of development of insomnia. Methods: A total of 120 patients with insomnia (78 females, 42 males; mean age ± standard deviation, 43.74 ± 13.02 years) and 120 good sleepers (67 females, 53 males; mean age, 42.69 ± 12.24 years) were recruited. The left hippocampus was segmented into anterior (L1), middle (L2), and posterior (L3) subregions. The right hippocampus was segmented into top anterior (R1), second top anterior (R2), middle (R3), posterior (R4), and last posterior (R5) subregions. Multivariate logistic regression was used to evaluate the associations of hippocampal volume (HV) of each subfield with the risk of the development of insomnia. Mediation analyses were performed to evaluate mediated associations among post-insomnia negative emotion, insomnia severity, and HV atrophy. A visual easy-to-deploy risk nomogram was used for individual prediction of risk of development of insomnia. Results: Hippocampal volume atrophy was identified in the L1, R1, and R2 subregions. L1 and R2 volume atrophy each predisposed to an ~3-fold higher risk of insomnia (L1, odds ratio: 2.90, 95% confidence intervals: [1.24, 6.76], p = 0.014; R2, 2.72 [1.19, 6.20], p = 0.018). Anxiety fully mediates the causal path of insomnia severity leading to R1 volume atrophy with a positive effect. We developed a practical and visual competing risk-nomogram tool for individual prediction of insomnia risk, which stratifies individuals into different levels of insomnia risk with the highest prediction accuracy of 97.4% and an average C-statistic of 0.83. Conclusion: Hippocampal atrophy in specific neurofunctional subfields was not only found to be associated with insomnia but also a significant risk factor predicting development of insomnia.

Gentiopicroside alleviates cardiac inflammation and fibrosis in T2DM rats through targeting Smad3 phosphorylation.

BACKGROUND: Cardiac fibrosis is a major structural change observed in the heart of patients with type 2 diabetes mellitus (T2DM), ultimately resulting in heart failure (HF). Suppression of inflammation is an effective therapeutic strategy for treating cardiac fibrosis and HF. Gentiopicroside (GPS), the primary component of Gentiana manshurica Kitagawa, possess potent anti-inflammatory activity. However, its cardioprotective role remains elusive. PURPOSE: We explored the potential cardioprotective role of GPS in T2DM rats and its underlying mechanisms. METHODS: T2DM rats built by high-fat diet and streptozotocin were orally administered 25, 50, or 100 mg/kg GPS, daily for 8 weeks. The positive control drug was Metformin (200 mg/kg/day). Primary cardiac fibroblasts (CFs) were induced by high glucose (30 mM) and subsequently treated with GPS (100 µM). Cardiac function and pathological changes were analyzed using echocardiography and histological staining. Potential targets of GPS were predicted using Molecular docking. Real-time PCR as well as western blotting were applied to verify the expression of objective genes. RESULTS: All three doses reduced fasting blood glucose levels, but only 50 and 100 mg/kg GPS improved cardiac function and alleviated inflammation and fibrosis in T2DM rats. GPS (100 mg/kg) exhibited a better effect, similar to that of metformin. Mechanistically, binding between GPS and the MH2 domain of Smad3 blocked high glucose-induced Smad3 phosphorylation, thus attenuating inflammation, oxidative stress, and activation in CFs. CONCLUSION: We, for the first time, demonstrated that GPS improved cardiac function in T2DM rats and elucidated the underlying mechanism through which GPS targeted Smad3 phosphorylation to suppress inflammation and activation in CFs, thereby revealing the potential application of GPS in HF therapy.

Heterogeneous microenvironment analysis to explore the potential regulatory role of endothelial-mesenchymal transition in idiopathic pulmonary fibrosis.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease mainly caused by excessive proliferation of fibroblasts and activation of myofibroblasts. The cellular microenvironment is mainly composed of different types of cellular components and extracellular matrix (ECM), whose changes directly affect cellular heterogeneity, resulting in immensely complex cellular interactions. However, microenvironment study is mainly focused on the pathological process of tumors, and the microenvironment changes during IPF development remain unclear. Methods: The current study intends to employ IPF-related single-cell sequencing and gene expression profile data to analyze the scores of different cell clusters in the IPF microenvironment, and exploit the underlying interaction between cells to illustrate the fundamental mechanism causing IPF. Results: Our analysis revealed that the amount of endothelial cells was obviously decreased, and the amount of fibroblasts and myofibroblasts was increased during the development of IPF, suggesting a possible endothelial-mesenchymal transition (EndMT) process. Furthermore, we found that the hub genes obtained through IPF-related gene expression profile analysis may play a regulative role in the number and function of endothelial cells and fibroblasts/myofibroblasts during IPF. Conclusions: Our research represents a valuable analysis of the cellular microenvironment, and provides a novel mechanistic insight into the pathobiology of not only EndMT in IPF, but also other traumatic fibrotic disease disorders.

A Critical Review of Resistance and Oxidation Mechanisms of Sb-Oxidizing Bacteria for the Bioremediation of Sb(III) Pollution.

Antimony (Sb) is a priority pollutant in many countries and regions due to its chronic toxicity and potential carcinogenicity. Elevated concentrations of Sb in the environmental originating from mining and other anthropogenic sources are of particular global concern, so the prevention and control of the source of pollution and environment remediation are urgent. It is widely accepted that indigenous microbes play an important role in Sb speciation, mobility, bioavailability, and fate in the natural environment. Especially, antimony-oxidizing bacteria can promote the release of antimony from ore deposits to the wider environment. However, it can also oxidize the more toxic antimonite [Sb(III)] to the less-toxic antimonate [Sb(V)], which is considered as a potentially environmentally friendly and efficient remediation technology for Sb pollution. Therefore, understanding its biological oxidation mechanism has great practical significance to protect environment and human health. This paper reviews studies of the isolation, identification, diversity, Sb(III) resistance mechanisms, Sb(III) oxidation characteristics and mechanism and potential application of Sb-oxidizing bacteria. The aim is to provide a theoretical basis and reference for the diversity and metabolic mechanism of Sb-oxidizing bacteria, the prevention and control of Sb pollution sources, and the application of environment treatment for Sb pollution.

Beyond Color: The New Carbon Ink.

For thousands of years, carbon ink has been used as a black color pigment for writing and painting purposes. However, recent discoveries of nanocarbon materials, including fullerenes, carbon nanotubes, graphene, and their various derivative forms, together with the advances in large-scale synthesis, are enabling a whole new generation of carbon inks that can serve as an intrinsically programmable materials platform for developing advanced functionalities far beyond color. The marriage between these multifunctional nanocarbon inks with modern printing technologies is facilitating and even transforming many applications, including flexible electronics, wearable and implantable sensors, actuators, and autonomous robotics. This review examines recent progress in the reborn field of carbon inks, highlighting their programmability and multifunctionality for applications in flexible electronics and stimuli-responsive devices. Current challenges and opportunities will also be discussed from a materials science perspective towards the advancement of carbon ink for new applications beyond color.

Massively parallel cantilever-free atomic force microscopy.

Resolution and field-of-view often represent a fundamental tradeoff in microscopy. Atomic force microscopy (AFM), in which a cantilevered probe deflects under the influence of local forces as it scans across a substrate, is a key example of this tradeoff with high resolution imaging being largely limited to small areas. Despite the tremendous impact of AFM in fields including materials science, biology, and surface science, the limitation in imaging area has remained a key barrier to studying samples with intricate hierarchical structure. Here, we show that massively parallel AFM with >1000 probes is possible through the combination of a cantilever-free probe architecture and a scalable optical method for detecting probe-sample contact. Specifically, optically reflective conical probes on a comparatively compliant film are found to comprise a distributed optical lever that translates probe motion into an optical signal that provides sub-10 nm vertical precision. The scalability of this approach makes it well suited for imaging applications that require high resolution over large areas.

The effects and safety of omega-3 fatty for acute lung injury: a systematic review and meta-analysis.

BACKGROUND: Several randomized controlled trials (RCTs) have compared the treatment of acute lung injury (ALI) with omega-3 fatty, yet the results remained inconsistent. Therefore, we attempted this meta-analysis to analyze the role of omega-3 fatty in the treatment of ALI patients. METHODS: We searched PubMed databases from inception date to October 31, 2019, for RCTs that compared the treatment of ALI with or without omega-3 fatty. Two authors independently screened the studies and extracted data from the published articles. Summary mean differences (MD) with 95% confidence intervals (CI) were calculated for each outcome by fixed- or random-effects model. RESULTS: Six RCTs with a total of 277 patients were identified, of whom 142 patients with omega-3 fatty acid treatment and 135 patients without omega-3 fatty treatment. Omega-3 fatty treatments significantly improve the PaO2 (MD = 13.82, 95% CI 8.55-19.09), PaO2/FiO2 (MD = 33.47, 95% CI 24.22-42.72), total protein (MD = 2.02, 95% CI 0.43-3.62) in ALI patients, and omega-3 fatty acid treatments reduced the duration of mechanical ventilation (MD = - 1.72, 95% CI - 2.84 to - 0.60) and intensive care unit stay (MD = - 1.29, 95% CI - 2.14 to - 0.43) in ALI patients. CONCLUSIONS: Omega-3 fatty can effectively improve the respiratory function and promote the recovery of ALI patients. Future studies focused on the long-term efficacy and safety of omega-3 fatty use for ALI are needed.

Photolithographic Patterning of Organic Color-Centers.

Organic color-centers (OCCs) have emerged as promising single-photon emitters for solid-state quantum technologies, chemically specific sensing, and near-infrared bioimaging. However, these quantum light sources are currently synthesized in bulk solution, lacking the spatial control required for on-chip integration. The ability to pattern OCCs on solid substrates with high spatial precision and molecularly defined structure is essential to interface electronics and advance their quantum applications. Herein, a lithographic generation of OCCs on solid-state semiconducting single-walled carbon nanotube films at spatially defined locations is presented. By using light-driven diazoether chemistry, it is possible to directly pattern p-nitroaryl OCCs, which demonstrate chemically specific spectral signatures at programmed positions as confirmed by Raman mapping and hyperspectral photoluminescence imaging. This light-driven technique enables the fabrication of OCC arrays on solid films that fluoresce in the shortwave infrared and presents an important step toward the direct writing of quantum emitters and other functionalities at the molecular level.

Design of Elastomer-CNT Film Photoactuators for Nanolithography.

Polymer pen lithography (PPL) is an approach to multiplexing scanning probe lithography, in which an array of probes on a compliant film-coated rigid substrate are used to write patterns on a surface. Recently, it was shown that these nominally passive pen arrays can be rendered photo-active by making them out of a polydimethylsiloxane (PDMS)⁻carbon nanotube (CNT) composite. While such photoactuated pens in principle represent a rapid, maskless, and versatile nanomanufacturing strategy, a key challenge that remains is learning how to effectively control the writing of each pen, individually. In this research, we studied the design of PDMS⁻CNT thin-film photoactuators and experimentally explored the role of illumination radius, film thickness, and CNT concentration. Additionally, we have proposed a model that predicts actuation efficiency, actuation time, and the crosstalk between pens. Based upon these results, we have generated a map of working efficiency to elucidate the ideal choice for specific actuation requirements. This work lays the foundation for studying further photoactuatable composite films as actuators in applications beyond lithography including soft robotics and adaptive optics.

A time-domain method for prediction of noise radiated from supersonic rotating sources in a moving medium.

This paper presents a time-domain method for noise prediction of supersonic rotating sources in a moving medium. The proposed approach can be interpreted as an extensive time-domain solution for the convected permeable Ffowcs Williams and Hawkings equation, which is capable of avoiding the Doppler singularity. The solution requires special treatment for construction of the emission surface. The derived formula can explicitly and efficiently account for subsonic uniform constant flow effects on radiated noise. Implementation of the methodology is realized through the Isom thickness noise case and high-speed impulsive noise prediction from helicopter rotors.

Gadolinium-conjugated star-block copolymer polylysine-modified polyethylenimine as high-performance T 1 MR imaging blood pool contrast agents.

Core-shell copolymers have received widespread attention because of their unique properties, such as suitable for surface modification and increasing the functionality. Thus, they have been increasingly used in many fields including biomedical, pharmaceutical, electronics and optics. Here, a new core-shell copolymer system was developed to synthesize potential blood pool contrast agent (CA) for magnetic resonance imaging (MRI). The novel CA with high T 1 relaxivity was synthesized by conjugating gadolinium (Gd) chelators onto star-block copolymer polyethylenimine-grafted poly(l-lysine) (PEI-PLL) nanoparticles (NPs). The T 1 relaxivity of PEI-PLL-DTPA-Gd NPs measured on a 7.0 T small animal MRI scanner was 8.289 mM-1 s-1, higher than that of T 1 contrast agents widely used in the clinic, such as Gd-DTPA (also known as Magnevist, r 1 = 4.273 mM-1 s-1). These results show that PEI-PLL-DTPA-Gd exhibits more efficient T 1 MR contrast enhancement compared to Gd-DTPA. More importantly, the PEI-PLL-DTPA-Gd core-shell NPs exhibited extremely low toxicity when measured against the HepG2 cell line over a similar concentration rang of Magnevist. In in vivo experiments, PEI-PLL-DTPA-Gd not only displayed good T 1 contrast enhancement for the abdominal aorta, but also showed prolonged blood circulation time compared with Gd-DTPA, which should enable longer acquisition time, for MR and MR angiographic images, with high resolution in clinical practice. PEI-PLL-DTPA-Gd NPs have potential to serve as high T 1 relaxivity blood pool MRI CA in the clinic.