Biomedical Technology最新文献

Flexible electronics are attracting considerable attention due to their promising performance including conductivity, stain- or pressure-sensing performance, skin-affinity, flexibility, etc. In particular, the structural design has promoted their properties and brought advanced functions, which make them valuable in biomedical applications including health monitoring, therapeutic applications and implantable devices. Herein, a review on the recent progress of flexible electronics with micro-/nano-structures is provided, involving the manufacturing technologies and applications in biomedical fields. Following these two sections, remaining challenges and the perspectives on future directions are also proposed.

The traditional membrane with single structure cannot satisfy complex clinical applications. Inspired by lotus leaf, a novel structure Janus membrane has achieved more attention recently. Janus membrane is a membrane structure which has two faces with opposite properties. This special structure endows it with asymmetric surface wettability, which can provide an intrinsic driving force to transport along a specified direction, thus achieve unidirectional liquid transport and selective liquid separation. Janus membrane has a promising future, and has been widely used in chemical fields such as self-cleaning, oil/water separation, mist collection, and desalination, while less studied in biomedical field. In this review, the biomedical applications especially in different stages of wound healing process, current challenges in fabrication process and future perspectives of Janus membranes in practical applications under different Janus models, such as hemostasis, bone regeneration, blood cell isolation and gastric mycosal defect will be discussed. It is expected that this unique structure can provide a good therapy prospect in biomedical fields.

Background

Liver fibrosis is recognized as a consequence of persistent liver damage. Hence, understanding the mechanisms of liver fibrosis could help patients reverse this process. Aggrephagy is a selective type of autophagy which is under study in various diseases. However, the investigation of aggrephagy in liver fibrosis has not been reported yet.

Methods

Five GEO databases were first batched into an integrated dataset by PCA analysis and facilitated for exploration of the aggrephagy-related genes. In addition, the diagnostic model under the aggrephagy-related genes was constructed by random forest. Then Western blot and immunofluorescence were employed in cells treated by autophagy-inhibitor Bafilomycin A1 to analyze whether the aggrephagy induced by liver fibrosis is necessary for aggregates degradation. Furthermore, the single cell data from GEO database and AUCell analysis functioned to detect the aggrephagy score. CellChat analysis compared the interaction strength and underlying receptor ligands between the different aggrephagy score groups. Furthermore, we used the monocle function to display the dynamic process from low aggrephagy score to high aggrephagy score groups. Finally, we used the consensus cluster to compare the clinical characteristics and underlying drug compounds under aggrephagy-score.

Results

First, we observed that aggrephagy score was much higher in the liver fibrosis group than in the normal group. Then our results showed that aggrephagy score was positively correlated with several metabolism pathways. In addition, aggrephagy related diagnostic model showed higher efficiency than other markers of liver fibrosis. Further experiments revealed that the removal of aggregates in liver fibrosis was depended on aggrephagy. We then observed that aggrephagy score and CFTR levels were dominantly located in hepatocytes from single-cell data. Moreover, the high aggrephagy-score group showed increased cell interaction strength, intercellular receptor-ligand signaling, and the transcription factor activity of HNF1B than the low aggrephagy-score groups. Hence, aggrephagy might be a promising target for liver fibrosis.

Conclusions

Our results showed that the aggrephagy score is a promising index for diagnosing liver fibrosis.

Background

Extracellular matrix (ECM) acts as a physical barrier to tumors, resulting in the lysis or delay of drug delivery. Integrins (ITGs) are essential for tumor cell-ECM interactions. Thus, we established a novel prognostic model to predict overall survival, immunotherapy benefits, and therapeutic agents in gastric cancer (GC) based on ITGs-related ECM landscape.

Methods

Using the TCGA-STAD dataset, we studied the genetic and transcriptional changes of ITGs. We used a merged cohort for ITGs survival analysis and determined molecular pattern clusters using consensus unsupervised clustering methodology. We confirmed the distinct ECM landscape between constructed clusters by performing gene set variation and Kaplan-Meier analysis. We utilized prognostic differentially expressed genes between clusters to develop a prognostic model utilizing logistic least absolute shrinkage and selection operator cox regression analysis, followed by stepwise multivariate Cox analysis in the training dataset. The model was validated by receiver operating characteristic curves and Kaplan-Meier analysis in the testing dataset and seven validation datasets. We compared our model to 35 previously published models. To analyze immune infiltration, we used multiple algorithms, which were further confirmed by single-cell RNA-sequencing and fluorescent multiplex immunohistochemistry. We explored tumor mutation burden (TMB), microsatellite instability-high (MSI-H) grade, immunotherapy response, chemotherapy sensitivity, and clinical significance between the low-risk and high-risk groups. Finally, we assessed the risk score in five reported molecular subtypes.

Results

The two ITGs-related clusters were identified, and their ECM landscapes were distinct. The prognostic model was constructed and had shown stable performance in internal and external validation. In addition, our model outperformed 35 previously published models. High-risk patients had a bad prognostic ECM landscape, high stromal cell inflammation, a lower TMB, a lower MSI-H grade, a worse tumor stage, a worse response to immunotherapy, and less sensitivity to chemotherapy. In five reported molecular subtypes, the worse subtypes showed a higher risk score.

Conclusions

The prognostic model could be an effective and promising tool for predicting prognosis and therapy response in GC patients.

As an emerging technology relevant to materials science, 3D printing technology simplifies material production process, shortens the preparation cycle, and provides a broader space for disease treatment. This review introduces the latest development in 3D printing, the goal is showing summary of the preparation and the utilization of this technology. We first describe the familiar biological ink for 3d printing. Then, we focus on different applications, including drug delivery, tumor modeling, and organ printing. Later, we described the application of this technology in some disciplines, including neurosurgery, gastrointestinal surgery, and orthopedics. Finally, the recent challenges and prospects of 3D printing are presented.

Nucleic acid amplification techniques are broadly employed in nucleic acid testing due to their efficient accumulation of nucleic acid sequences. With the development of biotechnology, they are further applied to proteins, living cells, extracellular vesicles (EVs) and even small molecule detection to amplify detection signals for ultra-sensitive bioanalysis. As important amplification techniques, isothermal amplification techniques, CRISPR/Cas system, DNA Walker and DNAzymes are playing an increasingly important role in signal magnification. Cooperating with functional nanomaterials, they present a wide availability in biosensing and bioimaging. This review gives a comprehensive summary of the four main signal amplification techniques mentioned above and their applications in biosensing and bioimaging. Finally, some of the challenges and further opportunities of nucleic acid amplification strategy in the current biomedical technology field are discussed.

Monoclonal antibodies targeting CTLA-4, PD-1/PD-L1 axis, and LAG-3, have shown unprecedented clinical success in melanoma. However, such immune checkpoint blockade (ICB) therapies failed to initiate primary immune responses or with limited durability. Here, we reviewed the mechanisms eliciting intrinsic resistance and adaptive resistance in melanoma patients. Furthermore, we introduced emerging nano-strategies to overcome the ICB by either enhancing tumour cell phagocytosis through checkpoint-mediated internalization or devising nano-immunomodulators for ICB combination therapy. These strategies may lead to clinical translations in the future.

Recently, scientists at Pohang University of Science and Technology in South Korea constructed a smart theranostic contact lens. The highly integrated smart contact lens is composed of an intraocular pressure (IOP) biosensor, a drug delivery system (DDS), a wireless communication system, as well as a circuit chip for IOP regulation. This design provides a new opportunity for wearable medical treatment in the individualized treatment of glaucoma and other ocular diseases.

Systemic lupus erythematosus (SLE) is a complex autoimmune disease that affects multiple organs and tissues. However, only a handful of new drugs have been FDA-approved for SLE since the 1950s. Therefore, novel treatments for SLE are urgently needed to be developed. In recent years, various engineering technologies such as tissue engineering, organs-on-chips, and intelligent delivery systems have been rapidly developed in the field of biomedicine. Notably, engineered nanocarriers and cell-based therapies can address the problems faced by traditional drug delivery and cell transplantation. They have proven effective in the treatment of many areas of disease, including autoimmune diseases. This is an important opportunity to break through the limited treatment options for SLE. In this review, we summarize the application progresses of engineering technologies and also propose their challenges in SLE treatment. This paper aims to help readers to understand the perspective of engineering technologies on the direction of SLE treatments in forthcoming years.

Coronavirus disease 2019 (COVID-19), a severely spreading pandemic, has dramatically brought physiological and economical burdens to people. Although the injectable vaccines have some achievements for coronavirus defense, they still generate accompanied pain, untoward reaction and cannot take part in mucosal immunity. Inhalable vaccines, as a safe, facile and efficient strategy, have been presented to protect body from virus by inducing robust mucosal immunity. Here, we give a perspective of an inhalable COVID-19 vaccine composed of lung-derived exosomes (a type of virus-like particle) conjugated with viral receptor-binding domain. The lung-derived exosomes act as carriers, such inhalable particles successfully reach at lung and reveal wider distribution and longer retention on respiratory mucosa. In addition, such vaccines induce the high production of specific antibodies and T cells in lung, significantly protecting host against coronavirus invasion. It is conceived that inhalable virus-like particles with long-term stability wound open a new avenue for vaccines delivery and further achieve vaccine popularization to against with COVID-19 pandemic.