Single-cell multi-omics in the study of digestive system cancers

Digestive system cancers are prevalent diseases with a high mortality rate, posing a significant threat to public health and economic burden. The diagnosis and treatment of digestive system cancer confront conventional cancer problems, such as tumor heterogeneity and drug resistance. Single-cell sequencing (SCS) emerged at times required and has developed from single-cell RNA-seq (scRNA-seq) to the single-cell multi-omics era represented by single-cell spatial transcriptomics (ST). This article comprehensively reviews the advances of single-cell omics technology in the study of digestive system tumors. While analyzing and summarizing the research cases, vital details on the sequencing platform, sample information, sampling method, and key findings are provided. Meanwhile, we summarize the commonly used SCS platforms and their features, as well as the advantages of multi-omics technologies in combination. Finally, the development trends and prospects of the application of single-cell multi-omics technology in digestive system cancer research are prospected.

Multifunctional polymeric nanofibrous scaffolds enriched with azilsartan medoxomil for enhanced wound healing

A prolonged and compromised wound healing process poses a significant clinical challenge, necessitating innovative solutions. This research investigates the potential application of nanotechnology-based formulations, specifically nanofiber (NF) scaffolds, in addressing this issue. The study focuses on the development and characterization of multifunctional nanofibrous scaffolds (AZL-CS/PVA-NF) composed of azilsartan medoxomil (AZL) enriched chitosan/polyvinyl alcohol (CS/PVA) through electrospinning. The scaffolds underwent comprehensive characterization both in vitro and in vivo. The mean diameter and tensile strength of AZL-CS/PVA-NF were determined to be 240.42 ± 3.55 nm and 18.05 ± 1.18 MPa, respectively. A notable drug release rate of 93.86 ± 2.04%, was observed from AZL-CS/PVA-NF over 48 h at pH 7.4. Moreover, AZL-CS/PVA-NF exhibited potent antimicrobial efficacy for Staphylococcus aureus and Pseudomonas aeruginosa. The expression levels of Akt and CD31 were significantly elevated, while Stat3 showed a decrease, indicating a heightened tissue regeneration rate with AZL-CS/PVA-NF compared to other treatment groups. In vivo ELISA findings revealed reduced inflammatory markers (IL-6, IL-1β, TNF-α) within treated skin tissue, implying a beneficial effect on injury repair. The comprehensive findings of the present endeavour underscore the superior wound healing activity of the developed AZL-CS/PVA-NF scaffolds in a Wistar rat full-thickness excision wound model. This indicates their potential as novel carriers for drugs and dressings in the field of wound care.

Pluronic F127 hydrogel-loaded extracellular vesicles from adipose-derived mesenchymal stem cells promote tracheal cartilage regeneration via SCNN1B delivery

Extracellular vesicles (EVs) derived from adipose-derived mesenchymal stem cells (AMSC-EVs) have been highlighted as a cell-free therapy due to their regenerative capability to enhance tissue and organ regeneration. Herein, we aimed to examine the mechanism of PF127-hydrogel@AMSC-EVs in promoting tracheal cartilage defect repair. Based on bioinformatics methods, SCNN1B was identified as a key gene for the osteogenic differentiation of AMSCs induced by AMSC-EVs. EVs were isolated from rat AMSCs and then loaded onto thermo-sensitive PF-127 hydrogel to develop PF127-hydrogel@AMSC-EVs. It was established that PF127-hydrogel@AMSC-EVs could effectively deliver SCNN1B into AMSCs, where SCNN1B promoted AMSC osteogenic differentiation. The promotive effect was evidenced by enhanced ALP activity, extracellular matrix mineralization, and expression of s-glycosaminoglycan, RUNX2, OCN, collagen II, PERK, and ATF4. Furthermore, the in vivo experiments revealed that PF127-hydrogel@AMSC-SCNN1B-EVs stimulated tracheal cartilage regeneration in rats through PERK/ATF4 signaling axis activation. Therefore, PF127-hydrogel@AMSC-SCNN1B-EVs may be a novel cell-free biomaterial to facilitate tracheal cartilage regeneration and cartilage injury repair.

Ferroptosis is involved in trophoblast cells cytotoxicity induced by black phosphorus nanoparticles

Black phosphorus (BP) is a new type of nanomaterial, which has been widely used in many biomedical fields due to its superior properties, but there are few studies on the toxicity of BP, especially in the reproductive system. To explore the effects of BP exposure on reproduction and reveal its molecular mechanism, we firstly investigated the potential toxicity of black phosphorus nanoparticles (BPNPs) in vivo. The results showed that BP exposure in pregnant mice can reduce the weight of fetal mice and placenta. H&E staining further indicated the changes of placental cross-section and vascular remodeling after BP treatment. Then, human exvillous trophoblast HTR8/SVneo was treated with different concentrations of BPNPs. We found that BPNPs induced significant cytotoxicity, including dose-dependent reduction of cell viability and proliferation. Trophoblast cell migration and invasion were also impaired by BPNPs exposure. Moreover, pretreatment with Cytochalasin D (Cyto-D), a classical phagocytic inhibitor, alleviated the decline of cell viability induced by BPNPs. Transcriptome sequencing showed that BPNPs exposure led to ferroptosis. Subsequently, the related indexes of ferroptosis were detected, including increase of iron ion concentration, decrease of the ferroptosis marker, GPX4 (Glutathione Peroxidase 4), increase of FTL (Ferritin Light Chain), and increase of lipid peroxidation indexes (MDA level and decrease of GSH level). In addition, ferroptosis inhibitors (Fer-1 and DFO) pretreatment can alleviate both the cytotoxic effects and functional impairment induced by BPNPs. In summary, our study confirmed the reproductive toxicity of BPNPs for the first time, and constructed BPNPs injury model in vitro using human villus trophoblast cells and revealed the role of ferroptosis in this process, which deepened our understanding of the biosafety of black phosphorus nanomaterials.

Advances in nano-immunotherapy for hematological malignancies

Hematological malignancies (HMs) encompass a diverse group of blood neoplasms with significant morbidity and mortality. Immunotherapy has emerged as a validated and crucial treatment modality for patients with HMs. Despite notable advancements having been made in understanding and implementing immunotherapy for HMs over the past decade, several challenges persist. These challenges include immune-related adverse effects, the precise biodistribution and elimination of therapeutic antigens in vivo, immune tolerance of tumors, and immune evasion by tumor cells within the tumor microenvironment (TME). Nanotechnology, with its capacity to manipulate material properties at the nanometer scale, has the potential to tackle these obstacles and revolutionize treatment outcomes by improving various aspects such as drug targeting and stability. The convergence of nanotechnology and immunotherapy has given rise to nano-immunotherapy, a specialized branch of anti-tumor therapy. Nanotechnology has found applications in chimeric antigen receptor T cell (CAR-T) therapy, cancer vaccines, immune checkpoint inhibitors, and other immunotherapeutic strategies for HMs. In this review, we delineate recent developments and discuss current challenges in the field of nano-immunotherapy for HMs, offering novel insights into the potential of nanotechnology-based therapeutic approaches for these diseases.

Exploring Biosensors' Scientific Production and Research Patterns: A Bibliometric Analysis

More sustainable biosensor production is growing in importance, allowing for the development of technological solutions for several industries, such as those in the health, chemical, and food sectors. Tracking the latest advancements in biosensors' scientific production is fundamental to determining the opportunities for the future of the biosensing field. This article aims to map scientific production in the biosensors field by running a bibliometric analysis of journal articles registered in the Web of Science database under biosensor-related vital concepts. The key concepts were selected by researchers and biosensor technology developers working on the BioAssembler Horizon project. The findings lead to identifying the scientific and technological knowledge base on biosensing devices and tracking the main scientific organisations developing this technology throughout the COVID-19 period (2019-2023). The institutional origin of the publications characterised the global distribution of related knowledge competencies and research partnerships. These results are discussed, shedding light on the scientific, economic, political, and structural factors that contribute to the formation of a scientific knowledge-based focus on the performance and design of these sensors. Moreover, the lack of scientific ties between the three axes of organisations producing expertise in this area (China, USA, and Russia) points towards the need to find synergies through new mechanisms of co-authorship and collaboration.

Antibacterial wound dressing with cross-linked electrospun surface from reduced graphene oxide doped polyvinyl alcohol/sodium caseinate blends

In this study, a new biomaterial with polyvinyl alcohol (PVA)/sodium caseinate (SodCa)/reduced graphene oxide (rGO) structure was developed. Antibacterial effective nanofibers were successfully produced by electrospinning method from 1%, 3%, 5%, and 7% rGO added PVA/SodCa (60:40, w:w) solution mixtures prepared for use as modern wound dressings. To create a usage area, especially in exuding wounds, hydrophilic PVA/SodCa/rGO electrospun mats were cross-linked by dipping them in a glutaraldehyde (GLA) bath. The surface micrographs of all nanofibers were homogeneous and smooth. rGO-doped biomaterials were obtained as thin nanofibers in the range of 301-348 nm. Nanofibers, which were completely soluble in water, after cross-linking preserved their existence in the range of 87%-81% at the end of the 24th hour in distilled water. It was reported that these biomaterials that persist in an aqueous environment show swelling behavior in the range of 275%-608%. The porosity of uncross-linked pure PVA/SodCa nanofibers increased by 46.75% after cross-linking. Moreover, the tensile strength of cross-linked PVA/SodCa electrospun mats increased in the presence of rGO. Provided that wound dressing is done every 24 h with 3% rGO-doped PVA/SodCa nanofiber and provided that wound dressing is done every 48 h with 5% rGO-doped PVA/SodCa nanofiber showed antibacterial activity against S. aureus as 99.38% and 99.55%, respectively.

MSC-Based Cell Therapy in Neurological Diseases: A Concise Review of the Literature in Pre-Clinical and Clinical Research

Mesenchymal stem cells (MSCs) are multipotent stromal cells with the ability to self-renew and multi-directional differentiation potential. Exogenously administered MSCs can migrate to damaged tissue sites and participate in the repair of damaged tissues. A large number of pre-clinical studies and clinical trials have demonstrated that MSCs have the potential to treat the abnormalities of congenital nervous system and neurodegenerative diseases. Therefore, MSCs hold great promise in the treatment of neurological diseases. Here, we summarize and highlight current progress in the understanding of the underlying mechanisms and strategies of MSC application in neurological diseases.

Recent Advances in Aptamer-Based Biosensors for Bacterial Detection

The rapid and sensitive detection of pathogenic bacteria is becoming increasingly important for the timely prevention of contamination and the treatment of infections. Biosensors based on nucleic acid aptamers, integrated with optical, electrochemical, and mass-sensitive analytical techniques, have garnered intense interest because of their versatility, cost-efficiency, and ability to exhibit high affinity and specificity in binding bacterial biomarkers, toxins, and whole cells. This review highlights the development of aptamers, their structural characterization, and the chemical modifications enabling optimized recognition properties and enhanced stability in complex biological matrices. Furthermore, recent examples of aptasensors for the detection of bacterial cells, biomarkers, and toxins are discussed. Finally, we explore the barriers to and discuss perspectives on the application of aptamer-based bacterial detection.

Engineered two-dimensional nanomaterials based diagnostics integrated with internet of medical things (IoMT) for COVID-19

More than four years have passed since an inimitable coronavirus disease (COVID-19) pandemic hit the globe in 2019 after an uncontrolled transmission of the severe acute respiratory syndrome (SARS-CoV-2) infection. The occurrence of this highly contagious respiratory infectious disease led to chaos and mortality all over the world. The peak paradigm shift of the researchers was inclined towards the accurate and rapid detection of diseases. Since 2019, there has been a boost in the diagnostics of COVID-19 via numerous conventional diagnostic tools like RT-PCR, ELISA, etc., and advanced biosensing kits like LFIA, etc. For the same reason, the use of nanotechnology and two-dimensional nanomaterials (2DNMs) has aided in the fabrication of efficient diagnostic tools to combat COVID-19. This article discusses the engineering techniques utilized for fabricating chemically active E2DNMs that are exceptionally thin and irregular. The techniques encompass the introduction of heteroatoms, intercalation of ions, and the design of strain and defects. E2DNMs possess unique characteristics, including a substantial surface area and controllable electrical, optical, and bioactive properties. These characteristics enable the development of sophisticated diagnostic platforms for real-time biosensors with exceptional sensitivity in detecting SARS-CoV-2. Integrating the Internet of Medical Things (IoMT) with these E2DNMs-based advanced diagnostics has led to the development of portable, real-time, scalable, more accurate, and cost-effective SARS-CoV-2 diagnostic platforms. These diagnostic platforms have the potential to revolutionize SARS-CoV-2 diagnosis by making it faster, easier, and more accessible to people worldwide, thus making them ideal for resource-limited settings. These advanced IoMT diagnostic platforms may help with combating SARS-CoV-2 as well as tracking and predicting the spread of future pandemics, ultimately saving lives and mitigating their impact on global health systems.

Quantum enhanced efficiency and spectral performance of paper-based flexible photodetectors functionalized with two dimensional materials

Flexible photodetectors (PDs) have exotic significance in recent years due to their enchanting potential in future optoelectronics. Moreover, paper-based fabricated PDs with outstanding flexibility unlock new avenues for future wearable electronics. Such PD has captured scientific interest for its efficient photoresponse properties due to the extraordinary assets like significant absorptive efficiency, surface morphology, material composition, affordability, bendability, and biodegradability. Quantum-confined materials harness the unique quantum-enhanced properties and hold immense promise for advancing both fundamental scientific understanding and practical implication. Two-dimensional (2D) materials as quantum materials have been one of the most extensively researched materials owing to their significant light absorption efficiency, increased carrier mobility, and tunable band gaps. In addition, 2D heterostructures can trap charge carriers at their interfaces, leading increase in photocurrent and photoconductivity. This review represents comprehensive discussion on recent developments in such PDs functionalized by 2D materials, highlighting charge transfer mechanism at their interface. This review thoroughly explains the mechanism behind the enhanced performance of quantum materials across a spectrum of figure of merits including external quantum efficiency, detectivity, spectral responsivity, optical gain, response time, and noise equivalent power. The present review studies the intricate mechanisms that reinforce these improvements, shedding light on the intricacies of quantum materials and their significant capabilities. Moreover, a detailed analysis of the technical applicability of paper-based PDs has been discussed with challenges and future trends, providing comprehensive insights into their practical usage in the field of future wearable and portable electronic technologies.

An overview of electrochemical biosensors used for COVID-19 detection

This short review presents the latest advances in the field of electrochemical biosensors, focusing particularly on impedimetric biosensors for the direct measurement of analytes. As a source of study we have chosen to describe these advances in the latest global health crisis originated from the COVID-19 pandemic, initiated by the SARS-CoV-2 virus. In this period, the necessity for swift and precise detection methods has grown rapidly due to an imminent need for the development of an analytical method to identify and isolate infected patients as an attempt to control the spreading of the disease. Traditional approaches such as the enzyme-linked immunosorbent assay (ELISA), were extensively used during the SARS-CoV-2 pandemic, but their drawbacks, including slow response time, became evident. In this context, the potential of electrochemical biosensors as an alternative for COVID-19 detection was emphasized. These biosensors merge electrochemical technology with bioreceptors, offering benefits such as rapidity, accuracy, portability, and real-time result provision. Additionally, we present instances of electrochemical biosensors modified with conductive polymers, eliminating the necessity for an electrochemical probe. The adaptability of the developed materials and devices facilitated the prompt production of electrochemical biosensors during the pandemic, creating opportunities for broader applications in infectious disease diagnosis.

Sonochemically synthesized black phosphorus nanoparticles: a promising candidate for piezocatalytic antibacterial activity with enhanced dielectric properties

The drawbacks inherent to traditional antibacterial therapies, coupled with the escalating prevalence of multi-drug resistant (MDR) microorganisms, have prompted the imperative need for novel antibacterial strategies. Accordingly, the emerging field of piezocatalysis in semiconductors harnesses mechanical stress to drive chemical reactions by utilizing piezo-generated free charge carriers, presenting a promising technology. To the best of our knowledge, this study is the first to provide a comprehensive overview of the eradication of pathogenic S. aureus bacteria using few-layer black phosphorus (SCBP) piezo catalyst under mechanical stimuli, along with the exploration of temperature dependent dielectric properties. The synthesis of the piezo catalysts involved a one-step cost-effective sonochemical method, and its structural, morphological, elemental, optical, and overall polarization properties were thoroughly characterized and compared with the traditional method-derived product (TABP). The synthesis-introduced defects, reduced crystalline diameters, modified bandgap (1.76 eV), nanoparticle aggregation, photoluminescence quenching, along with interfacial polarization, synergistically contribute to SCBP's exceptional dielectric response (4.596 × 107 @40 Hz), which in turn enhanced the piezocatalytic activity. When subjected to soft ultrasound stimulation at 15 kHz, the piezo catalyst SCBP demonstrated significant ROS-mediated antibacterial activity, resulting in a ∼94.7% mortality rate within 40 minutes. The impact of this study extends to cost-effective energy storage devices and advances in antibacterial therapy, opening new dimensions in both fields.

Cell Type- and Age-Specific Expression of lncRNAs across Kidney Cell Types

Key Points

Background

Accumulated evidence demonstrates that long noncoding RNAs (lncRNAs) regulate cell differentiation and homeostasis, influencing kidney aging and disease. Despite their versatility, the function of lncRNA remains poorly understood because of the lack of a reference map of lncRNA transcriptome in various cell types.

Methods

In this study, we used a targeted single-cell RNA sequencing method to enrich and characterize lncRNAs in individual cells. We applied this method to various mouse tissues, including normal and aged kidneys.

Results

Through tissue-specific clustering analysis, we identified cell type–specific lncRNAs that showed a high correlation with known cell-type marker genes. Furthermore, we constructed gene regulatory networks to explore the functional roles of differentially expressed lncRNAs in each cell type. In the kidney, we observed dynamic expression changes of lncRNAs during aging, with specific changes in glomerular cells. These cell type– and age-specific expression patterns of lncRNAs suggest that lncRNAs may have a potential role in regulating cellular processes, such as immune response and energy metabolism, during kidney aging.

Conclusions

Our study sheds light on the comprehensive landscape of lncRNA expression and function and provides a valuable resource for future analysis of lncRNAs (https://gist-fgl.github.io/sc-lncrna-atlas/).

Nanoscale Evaluation of the Degradation Stability of Black Phosphorus Nanosheets Functionalized with PEG and Glutathione-Stabilized Doxorubicin Drug-Loaded Gold Nanoparticles in Real Functionalized System

Two-dimensional black phosphorus (2D BP) has attracted significant research interest in the field of biomedical applications due to its unique characteristics, including high biocompatibility, impressive drug-loading efficiency, phototherapeutic ability, and minimal side effects. However, its puckered honeycomb lattice structure with lone-pair electrons of BP leads to higher sensitivity and chemical reactivity towards H2O and O2 molecules, resulting in the degradation of the structure with physical and chemical changes. In our study, we synthesize polyethylene glycol (PEG) and glutathione-stabilized doxorubicin drug-assembled Au nanoparticle (Au-GSH-DOX)-functionalized BP nanosheets (BP-PEG@Au-GSH-DOX) with improved degradation stability, biocompatibility, and tumor-targeting ability. Transmission electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy indicate the nanoscale degradation behavior of synthesized nanoconjugates in three different environmental exposure conditions, and the results demonstrate the remarkable nanoscale stability of BP-PEG@Au-GSH-DOX against the degradation of BP, which provides significant interest in employing 2D BP-based nanotherapeutic agents for tumor-targeted cancer phototherapy.

Mesenchymal stem cells for cartilage regeneration: Insights into molecular mechanism and therapeutic strategies

The use of mesenchymal stem cells (MSCs) in cartilage regeneration has gained significant attention in regenerative medicine. This paper reviews the molecular mechanisms underlying MSC-based cartilage regeneration and explores various therapeutic strategies to enhance the efficacy of MSCs in this context. MSCs exhibit multipotent capabilities and can differentiate into various cell lineages under specific microenvironmental cues. Chondrogenic differentiation, a complex process involving signaling pathways, transcription factors, and growth factors, plays a pivotal role in the successful regeneration of cartilage tissue. The chondrogenic differentiation of MSCs is tightly regulated by growth factors and signaling pathways such as TGF-β, BMP, Wnt/β-catenin, RhoA/ROCK, NOTCH, and IHH (Indian hedgehog). Understanding the intricate balance between these pathways is crucial for directing lineage-specific differentiation and preventing undesirable chondrocyte hypertrophy. Additionally, paracrine effects of MSCs, mediated by the secretion of bioactive factors, contribute significantly to immunomodulation, recruitment of endogenous stem cells, and maintenance of chondrocyte phenotype. Pre-treatment strategies utilized to potentiate MSCs, such as hypoxic conditions, low-intensity ultrasound, kartogenin treatment, and gene editing, are also discussed for their potential to enhance MSC survival, differentiation, and paracrine effects. In conclusion, this paper provides a comprehensive overview of the molecular mechanisms involved in MSC-based cartilage regeneration and outlines promising therapeutic strategies. The insights presented contribute to the ongoing efforts in optimizing MSC-based therapies for effective cartilage repair.

Preclinical evaluation of an 18F-labeled Tenascin-C aptamer for PET imaging of atherosclerotic plaque in mouse models of atherosclerosis

Tenascin-C is an extracellular matrix glycoprotein strongly expressed in coronary atherosclerotic plaque. Aptamers are single-stranded oligonucleotides that bind to specific target molecules with high affinity. This study hypothesized that tenascin-C expression at atherosclerotic plaque in vivo could be detected by tenascin-C specific aptamers using positron emission tomography (PET). This paper reports the radiosynthesis of a fluorine-18 (18F)-labeled tenascin-C aptamer for the biodistribution and PET imaging of the tenascin-C expression in apolipoprotein E-deficient (ApoE-/-) mice. The aortas ApoE-/- mice showed significantly increased positive areas of Oil red O staining than control C57BL/6 mice, and tenascin-C expression was detected in foam cells accumulated in the subendothelial lesions of ApoE-/- mice. The ex vivo biodistribution of the 18F-labeled tenascin-C aptamer showed significantly increased uptake at the aorta of ApoE-/- mice, and ex vivo autoradiography of aorta revealed the high accumulation of the 18F-labeled tenascin-C aptamer in the atherosclerotic lesions of ApoE-/- mice, which was consistent with the location of the atherosclerotic plaques detected by Oil red O staining. PET imaging of the 18F-labeled tenascin-C aptamer revealed a significantly higher mean standardized uptake in the aorta of the ApoE-/- mice than the control C57BL/6 mice. These data highlight the potential use of tenascin-C aptamer to diagnose atherosclerotic lesions in vivo.

Injectable, Electroconductive, Free Radical Scavenging Silk Fibroin/Black Phosphorus/Glycyrrhizic Acid Nanocomposite Hydrogel for Enhancing Spinal Cord Repair

Spinal cord injury (SCI) often leads to a severe permanent disability. A poor inflammatory microenvironment and nerve electric signal conduction block are the main reasons for difficulty in spinal cord nerve regeneration. In this study, black phosphorus (BP) and glycyrrhizic acid (GA) are integrated into methacrylate-modified silk fibroin (SF) to construct a bifunctional injectable hydrogel (SF/BP/GA) with appropriate conductivity and the ability to inhibit inflammation to promote neuronal regeneration after SCI. This work discovers that the SF/BP/GA hydrogel can reduce the oxidative damage mediated by oxygen free radicals, promote the polarization of macrophages toward the anti-inflammatory M2 phenotype, reduce the expression of inflammatory factors, and improve the inflammatory microenvironment. Moreover, it induces neural stem cell (NSC) differentiation and neurosphere formation, restores signal conduction at the SCI site in vivo, and ameliorates motor function in mice with spinal cord hemisection, revealing a significant neural repair effect. An injectable, electroconductive, free-radical-scavenging hydrogel is a promising therapeutic strategy for SCI repair.

Linker-free Functionalization of Phosphorene Nanosheets by Sialic Acid Biomolecules

The importance of sialic acid on cell functions has been recently unveiled, and consequently, great attention has been paid to its interaction with tumor cells. In this line of research, we have realized phosphorene nanosheets functionalized with sialic acid molecules for biological applications with no need for another linker molecule. The formation of phosphorene sheets is feasible by using hydrogen plasma treatment and conversion of amorphous phosphorus on silicon substrates into highly crystalline nanosheets. Through immersion of these freshly prepared nanosheets into an aqueous solution containing sialic acid molecules, the formation of chemical binding between biomolecules and P atoms is initiated to form a carpet-like coverage. We have studied these structures by using Raman spectroscopy, electron microscopy, FTIR-ATR spectroscopy, and X-ray photoelectron spectroscopy. While XPS supports the passivation of sialic-activated phosphorene nanosheets (SAP) against oxidation in air or aqueous solutions, the FTIR analysis corroborates the evolution of P-O-C and P-C bonds between such biomolecules and the sheet surface. Moreover, the high-resolution TEM images demonstrate a considerable reduction in the lattice spacing from 0.32 nm for pristine phosphorene to 0.30 nm. Similarly, Raman spectroscopy depicts a shift in A2g in-plane vibrations, owing to the evolution of stress in the passivated sheets. To investigate their biocompatibility, we examined the toxicity of these bioactivated structures and observed no or little sign of toxicity. For the latter evaluation, we exploited MTT, flow cytometry, and animal models for in vivo investigations.

Glucose Oxidase Activity Colorimetric Assay Using Redox-Sensitive Electrochromic Nanoparticle-Functionalized Paper Sensors

Glucose oxidase (GOx) activity assays are vital for various applications, including glucose metabolism estimation and fungal testing. However, conventional methods involve time-consuming and complex procedures. In this study, we present a colorimetric platform for in situ GOx activity measurement utilizing redox-sensitive electrochromic nanoparticles based on polyaniline (PAni). The glucose-adsorbed colorimetric paper sensor, herein termed Glu@CPS, is created by immobilizing ferrocene and glucose onto paper substrates that have been functionalized with PAni nanoparticles. Glu@CPS not only demonstrated rapid detection (within 5 min) but also exhibited remarkable selectivity for GOx and a limit of detection as low as 1.25 μM. Moreover, Glu@CPS demonstrated consistent accuracy in the measurement of GOx activity, exhibiting no deviations even after being stored at ambient temperature for a duration of one month. To further corroborate the effectiveness of this method, we applied Glu@CPS in the detection of GOx activity in a moldy red wine. The results highlight the promising potential of Glu@CPS as a convenient and precise platform for GOx activity measurement in diverse applications including food quality control, environmental monitoring, and early detection of fungal contamination.

Graphene transistor-based biosensors for rapid detection of SARS-CoV-2

Field-effect transistor (FET) biosensors use FETs to detect changes in the amount of electrical charge caused by biomolecules like antigens and antibodies. COVID-19 can be detected by employing these biosensors by immobilising bio-receptor molecules that bind to the SARS-CoV-2 virus on the FET channel surface and subsequent monitoring of the changes in the current triggered by the virus. Graphene Field-effect Transistor (GFET)-based biosensors utilise graphene, a two-dimensional material with high electrical conductivity, as the sensing element. These biosensors can rapidly detect several biomolecules including the SARS-CoV-2 virus, which is responsible for COVID-19. GFETs are ideal for real-time infectious illness diagnosis due to their great sensitivity and specificity. These graphene transistor-based biosensors could revolutionise clinical diagnostics by generating fast, accurate data that could aid pandemic management. GFETs can also be integrated into point-of-care (POC) diagnostic equipment. Recent advances in GFET-type biosensors for SARS-CoV-2 detection are discussed here, along with their associated challenges and future scope.

Exploring the current landscape of single-cell RNA sequencing applications in gastric cancer research

Gastric cancer (GC) represents a major global health burden and is responsible for a significant number of cancer-related fatalities. Its complex nature, characterized by heterogeneity and aggressive behaviour, poses considerable challenges for effective diagnosis and treatment. Single-cell RNA sequencing (scRNA-seq) has emerged as an important technique, offering unprecedented precision and depth in gene expression profiling at the cellular level. By facilitating the identification of distinct cell populations, rare cells and dynamic transcriptional changes within GC, scRNA-seq has yielded valuable insights into tumour progression and potential therapeutic targets. Moreover, this technology has significantly improved our comprehension of the tumour microenvironment (TME) and its intricate interplay with immune cells, thereby opening avenues for targeted therapeutic strategies. Nonetheless, certain obstacles, including tumour heterogeneity and technical limitations, persist in the field. Current endeavours are dedicated to refining protocols and computational tools to surmount these challenges. In this narrative review, we explore the significance of scRNA-seq in GC, emphasizing its advantages, challenges and potential applications in unravelling tumour heterogeneity and identifying promising therapeutic targets. Additionally, we discuss recent developments, ongoing efforts to overcome these challenges, and future prospects. Although further enhancements are required, scRNA-seq has already provided valuable insights into GC and holds promise for advancing biomedical research and clinical practice.

Improving osseointegration and antimicrobial properties of titanium implants with black phosphorus nanosheets-hydroxyapatite composite coatings for vascularized bone regeneration

For decades, titanium implants have shown impressive advantages in bone repair. However, the preparation of implants with excellent antimicrobial properties as well as better osseointegration ability remains difficult for clinical application. In this study, black phosphorus nanosheets (BPNSs) were doped into hydroxyapatite (HA) coatings using electrophoretic deposition. The coatings' surface morphology, roughness, water contact angle, photothermal properties, and antibacterial properties were investigated. The BP/HA coating exhibited a surface roughness of 59.1 nm, providing an ideal substrate for cell attachment and growth. The water contact angle on the BP/HA coating was measured to be approximately 8.55°, indicating its hydrophilic nature. The BPNSs demonstrated efficient photothermal conversion, with a temperature increase of 42.2°C under laser irradiation. The BP/HA composite coating exhibited a significant reduction in bacterial growth, with inhibition rates of 95.6% and 96.1% against Staphylococcus aureus and Escherichia coli. In addition, the cytocompatibility of the composite coating was evaluated by cell adhesion, CCK8 and AM/PI staining; the effect of the composite coating in promoting angiogenesis was assessed by scratch assay, transwell assay, and protein blotting; and the osteoinductivity of the composite coating was evaluated by alkaline phosphatase assay, alizarin red staining, and Western blot. The results showed that the BP/HA composite coating exhibited superior performance in promoting biological functions such as cell proliferation and adhesion, antibacterial activity, osteogenic differentiation, and angiogenesis, and had potential applications in vascularized bone regeneration.

Mesenchymal stem cell therapy in diabetic foot ulcer: An updated comprehensive review

Background

Diabetes has evolved into a worldwide public health issue. One of the most serious complications of diabetes is diabetic foot ulcer (DFU), which frequently creates a significant financial strain on patients and lowers their quality of life. Up until now, there has been no curative therapy for DFU, only symptomatic relief or an interruption in the disease's progression. Recent studies have focused attention on mesenchymal stem cells (MSCs), which provide innovative and potential treatment candidates for several illnesses as they can differentiate into various cell types. They are mostly extracted from the placenta, adipose tissue, umbilical cord (UC), and bone marrow (BM). Regardless of their origin, they show comparable features and small deviations. Our goal is to investigate MSCs' therapeutic effects, application obstacles, and patient benefit strategies for DFU therapy.

Methodology

A comprehensive search was conducted using specific keywords relating to DFU, MSCs, and connected topics in the databases of Medline, Scopus, Web of Science, and PubMed. The main focus of the selection criteria was on English-language literature that explored the relationship between DFU, MSCs, and related factors.

Results and Discussion

Numerous studies are being conducted and have demonstrated that MSCs can induce re-epithelialization and angiogenesis, decrease inflammation, contribute to immunological modulation, and subsequently promote DFU healing, making them a promising approach to treating DFU. This review article provides a general snapshot of DFU (including clinical presentation, risk factors and etiopathogenesis, and conventional treatment) and discusses the clinical progress of MSCs in the management of DFU, taking into consideration the side effects and challenges during the application of MSCs and how to overcome these challenges to achieve maximum benefits.

Conclusion

The incorporation of MSCs in the management of DFU highlights their potential as a feasible therapeutic strategy. Establishing a comprehensive understanding of the complex relationship between DFU pathophysiology, MSC therapies, and related obstacles is essential for optimizing therapy outcomes and maximizing patient benefits.

Self-delivery photothermal-boosted-nanobike multi-overcoming immune escape by photothermal/chemical/immune synergistic therapy against HCC

Immune checkpoint inhibitors (ICIs) combined with antiangiogenic therapy have shown encouraging clinical benefits for the treatment of unresectable or metastatic hepatocellular carcinoma (HCC). Nevertheless, therapeutic efficacy and wide clinical applicability remain a challenge due to "cold" tumors' immunological characteristics. Tumor immunosuppressive microenvironment (TIME) continuously natural force for immune escape by extracellular matrix (ECM) infiltration, tumor angiogenesis, and tumor cell proliferation. Herein, we proposed a novel concept by multi-overcoming immune escape to maximize the ICIs combined with antiangiogenic therapy efficacy against HCC. A self-delivery photothermal-boosted-NanoBike (BPSP) composed of black phosphorus (BP) tandem-augmented anti-PD-L1 mAb plus sorafenib (SF) is meticulously constructed as a triple combination therapy strategy. The simplicity of BPSP's composition, with no additional ingredients added, makes it easy to prepare and presents promising marketing opportunities. (1) NIR-II-activated BPSP performs photothermal therapy (PTT) and remodels ECM by depleting collagen I, promoting deep penetration of therapeutics and immune cells. (2) PTT promotes SF release and SF exerts anti-vascular effects and down-regulates PD-L1 via RAS/RAF/ERK pathway inhibition, enhancing the efficacy of anti-PD-L1 mAb in overcoming immune evasion. (3) Anti-PD-L1 mAb block PD1/PD-L1 recognition and PTT-induced ICD initiates effector T cells and increases response rates of PD-L1 mAb. Highly-encapsulated BPSP converted 'cold' tumors into 'hot' ones, improved CTL/Treg ratio, and cured orthotopic HCC tumors in mice. Thus, multi-overcoming immune escape offers new possibilities for advancing immunotherapies, and photothermal/chemical/immune synergistic therapy shows promise in the clinical development of HCC.

Smartphone-based device for point-of-care diagnostics of pulmonary inflammation using convolutional neural networks (CNNs)

In pulmonary inflammation diseases, like COVID-19, lung involvement and inflammation determine the treatment regime. Respiratory inflammation is typically arisen due to the cytokine storm and the leakage of the vessels for immune cells recruitment. Currently, such a situation is detected by the clinical judgment of a specialist or precisely by a chest CT scan. However, the lack of accessibility to the CT machines in many poor medical centers as well as its expensive service, demands more accessible methods for fast and cheap detection of lung inflammation. Here, we have introduced a novel method for tracing the inflammation and lung involvement in patients with pulmonary inflammation, such as COVID-19, by a simple electrolyte detection in their sputum samples. The presence of the electrolyte in the sputum sample results in the fern-like structures after air-drying. These fern patterns are different in the CT positive and negative cases that are detected by an AI application on a smartphone and using a low-cost and portable mini-microscope. Evaluating 160 patient-derived sputum sample images, this method demonstrated an interesting accuracy of 95%, as confirmed by CT-scan results. This finding suggests that the method has the potential to serve as a promising and reliable approach for recognizing lung inflammatory diseases, such as COVID-19.

Current advances in engineering meniscal tissues: insights into 3D printing, injectable hydrogels and physical stimulation based strategies

The knee meniscus is the cushioning fibro-cartilage tissue present in between the femoral condyles and tibial plateau of the knee joint. It is largely avascular in nature and suffers from a wide range of tears and injuries caused by accidents, trauma, active lifestyle of the populace and old age of individuals. Healing of the meniscus is especially difficult due to its avascularity and hence requires invasive arthroscopic approaches such as surgical resection, suturing or implantation. Though various tissue engineering approaches are proposed for the treatment of meniscus tears, three-dimensional (3D) printing/bioprinting, injectable hydrogels and physical stimulation involving modalities are gaining forefront in the past decade. A plethora of new printing approaches such as direct light photopolymerization and volumetric printing, injectable biomaterials loaded with growth factors and physical stimulation such as low-intensity ultrasound approaches are being added to the treatment portfolio along with the contemporary tear mitigation measures. This review discusses on the necessary design considerations, approaches for 3D modeling and design practices for meniscal tear treatments within the scope of tissue engineering and regeneration. Also, the suitable materials, cell sources, growth factors, fixation and lubrication strategies, mechanical stimulation approaches, 3D printing strategies and injectable hydrogels for meniscal tear management have been elaborated. We have also summarized potential technologies and the potential framework that could be the herald of the future of meniscus tissue engineering and repair approaches.

Development of Super-Paramagnetic Iron Oxide Nanoparticle-Coated Melt Electrowritten Scaffolds for Biomedical Applications

Polycaprolactone (PCL) is usually the material chosen for melt electrowriting (MEW) due to its biocompatibility, mechanical strength, and melt processability. This work first investigates the effect of different processing parameters to obtain optimum PCL-MEW scaffolds. Secondly, to increase PCL`s hydrophilicity and cell affinity, and to enable coating with superparamagnetic iron oxide nanoparticles (SPIONs) and silica-coated-SPIONs (Si-SPIONs), the scaffolds are modified with alkaline surface treatment. Finally, SPIONs and Si-SPIONs are successfully coated on MEW scaffolds. Results show that reproducible scaffolds are fabricated. Additionally, the alkaline treatment does not change the three-dimensional morphology of scaffolds while reducing fiber diameter. Furthermore, SEM images and ATR-FTIR results confirmed that SPIONs and Si-SPIONs-were coated on scaffolds. A cytocompatibility assay showed a non-toxic effect on MG-63 osteoblast-like cells in all scaffolds. Additionally, higher MC3T3-E1 pre-osteoblastic cell adhesion efficiency and proliferation are achieved for the alkaline-treated scaffolds and SPIONs/Si-SPIONs-coated scaffolds. All samples demonstrated the ability to generate heat, useful for hyperthermia-treatment, when subjected to an alternating magnetic field. Overall, the findings suggest that the strategy of coating PCL-MEW scaffolds with SPIONs/Si-SPIONs has the potential to improve scaffold performance for biomedical applications, especially for producing magnetically responsive MEW scaffolds.

Hydrophilic/Hydrophobic Janus Nanofibers Containing Compound K for Cartilage Regeneration

Introduction

Cartilage regeneration is a challenging issue due to poor regenerative properties of tissues. Electrospun nanofibers hold enormous potentials for treatments of cartilage defects. However, nanofibrous materials used for the treatment of cartilage defects often require physical and/or chemical modifications to promote the adhesion, proliferation, and differentiation of cells. Thus, it is highly desirable to improve their surface properties with functionality. We aim to design hydrophilic, adhesive, and compound K-loaded nanofibers for treatments of cartilage defects.

Methods

Hydrophilic and adhesive compound K-containing polycaprolactone nanofibers (CK/PCL NFs) were prepared by coatings of gallic acid-conjugated chitosan (CHI-GA). Therapeutic effects of CHI-GA/CK/PCL NFs were assessed by the expression level of genes involved in the cartilage matrix degradation, inflammatory response, and lipid accumulations in the chondrocytes. In addition, Cartilage damage was evaluated by safranin O staining and immunohistochemistry of interleukin-1β (IL-1β) using OA animal models. To explore the pathway associated with therapeutic effects of CHI-GA/CK/PCL NFs, cell adhesion, phalloidin staining, and the expression level of integrins and peroxisome proliferator-activated receptor (PPARs) were evaluated.

Results

CHI-GA-coated side of the PCL NFs showed hydrophilic and adhesive properties, whereas the unmodified opposite side remained hydrophobic. The expression levels of genes involved in the degradation of the cartilage matrix, inflammation, and lipogenesis were decreased in CHI-GA/CK/PCL NFs owing to the release of CK. In vivo implantation of CHI-GA/CK/PCL NFs into the cartilage reduced cartilage degradation induced by destabilization of the medial meniscus (DMM) surgery. Furthermore, the accumulation of lipid deposition and expression levels of IL-1β was reduced through the upregulation of PPAR.

Conclusion

CHI-GA/CK/PCL NFs were effective in the treatments of cartilage defects by inhibiting the expression levels of genes involved in cartilage degradation, inflammation, and lipogenesis as well as reducing lipid accumulation and the expression level of IL-1β via increasing PPAR.

Combination-Lock SlipChip Integrating Nucleic Acid Sample Preparation and Isothermal LAMP Amplification for the Detection of SARS-CoV-2

Nucleic acid analysis with an easy-to-use workflow, high specificity and sensitivity, independence of sophisticated instruments, and accessibility outside of the laboratory is highly desirable for the detection and monitoring of infectious diseases. Integration of laboratory-quality sample preparation on a hand-held system is critical for performance. A SlipChip device inspired by the combination lock can perform magnetic bead-based nucleic acid extraction with several clockwise and counterclockwise rotations. A palm-sized base station was developed to assist sample preparation and provide thermal control of isothermal nucleic acid amplification without plug-in power. The loop-mediated isothermal amplification reaction can be performed with a colorimetric method and directly analyzed by the naked eye or with a mobile phone app. This system achieves good bead recovery during the sample preparation workflow and has minimal residue carryover from the lysis and elution buffers. Its performance is comparable to that of the standard laboratory protocol with real-time qPCR amplification methods. The entire workflow is completed in less than 35 min and the device can achieve 500 copies/mL sensitivity. Thirty clinical nasal swab samples were collected and tested with a sensitivity of 95% and a specificity of 100% for SARS-CoV-2. This combination-lock SlipChip provides a promising fast, easy-to-use nucleic acid test with bead-based sample preparation that produces laboratory-quality results for point-of-care settings, especially in home use applications.

DNA and Nanomaterials: A Functional Combination for DNA Sensing

Recent decades have experienced tough situations due to the lack of reliable diagnostic facilities. The most recent cases occurred during the pandemic, where researchers observed the lack of diagnostic facilities with precision. Microorganisms and viral disease's ability to escape diagnosis has been a global challenge. DNA always has been a unique moiety with a strong and precise base-paired structure. DNA in human and foreign particles makes identification possible through base pairing. Since then, researchers have focused heavily on designing diagnostic assays targeting DNA in particular. Moreover, DNA nanotechnology has contributed vastly to designing composite nanomaterials by combining DNA/nucleic acids with functional nanomaterials and inorganic nanoparticles exploiting their physicochemical properties. These nanomaterials often exhibit unique or enhanced properties due to the synergistic activity of the many components. The capabilities of DNA and additional nanomaterials have shown the combination of robust and advanced tailoring of biosensors. Preceding findings state that the conventional strategies have exhibited certain limitations such as a low range of target detection, less biodegradability, subordinate half-life, and high susceptibility to microenvironments; however, a DNA-nanomaterial-based biosensor has overcome these limitations meaningfully. Additionally, the unique properties of nucleic acids have been studied extensively due to their high signal conduction abilities. Here, we review recent studies on DNA-nanomaterial-based biosensors, their mechanism of action, and improved/updated strategies in vivo and in situ. Furthermore, this review highlights the recent methodologies on DNA utilization to exploit the interfacial properties of nanomaterials in DNA sensing. Lastly, the review concludes with the limitations/challenges and future directions.

Silver Nanoparticles In Situ Synthesized and Incorporated in Uniaxial and Core-Shell Electrospun Nanofibers to Inhibit Coronavirus

In the present study, we sought to develop materials applicable to personal and collective protection equipment to mitigate SARS-CoV-2. For this purpose, AgNPs were synthesized and stabilized into electrospinning nanofiber matrices (NMs) consisting of poly(vinyl alcohol) (PVA), chitosan (CHT), and poly-ε-caprolactone (PCL). Uniaxial nanofibers of PVA and PVA/CHT were developed, as well as coaxial nanofibers of PCL[PVA/CHT], in which the PCL works as a shell and the blend as a core. A crucial aspect of the present study is the in situ synthesis of AgNPs using PVA as a reducing and stabilizing agent. This process presents few steps, no additional toxic reducing agents, and avoids the postloading of drugs or the posttreatment of NM use. In general, the in situ synthesized AgNPs had an average size of 11.6 nm, and the incorporated nanofibers had a diameter in the range of 300 nm, with high uniformity and low polydispersity. The NM's spectroscopic, thermal, and mechanical properties were appropriate for the intended application. Uniaxial (PVA/AgNPs and PVA/CHT/AgNPs) and coaxial (PCL[PVA/CHT/AgNPs]) NMs presented virucidal activity (log's reduction ≥ 5) against mouse hepatitis virus (MHV-3) genus Betacoronavirus strains. In addition to that, the NMs did not present cytotoxicity against fibroblast cells (L929 ATCC® CCL-1TM lineage).

Advances in the Application of Black Phosphorus-Based Composite Biomedical Materials in the Field of Tissue Engineering

Black Phosphorus (BP) is a new semiconductor material with excellent biocompatibility, degradability, and optical and electrophysical properties. A growing number of studies show that BP has high potential applications in the biomedical field. This article aims to systematically review the research progress of BP composite medical materials in the field of tissue engineering, mining BP in bone regeneration, skin repair, nerve repair, inflammation, treatment methods, and the application mechanism. Furthermore, the paper discusses the shortcomings and future recommendations related to the development of BP. These shortcomings include stability, photothermal conversion capacity, preparation process, and other related issues. However, despite these challenges, the utilization of BP-based medical materials holds immense promise in revolutionizing the field of tissue repair.

Mesenchymal stromal cells derived from various tissues: Biological, clinical and cryopreservation aspects: Update from 2015 review

Mesenchymal stromal cells (MSCs) have become one of the most investigated and applied cells for cellular therapy and regenerative medicine. In this update of our review published in 2015, we show that studies continue to abound regarding the characterization of MSCs to distinguish them from other similar cell types, the discovery of new tissue sources of MSCs, and the confirmation of their properties and functions that render them suitable as a therapeutic. Because cryopreservation is widely recognized as the only technology that would enable the on-demand availability of MSCs, here we show that although the traditional method of cryopreserving cells by slow cooling in the presence of 10% dimethyl sulfoxide (Me2SO) continues to be used by many, several novel MSC cryopreservation approaches have emerged. As in our previous review, we conclude from these recent reports that viable and functional MSCs from diverse tissues can be recovered after cryopreservation using a variety of cryoprotectants, freezing protocols, storage temperatures, and periods of storage. We also show that for logistical reasons there are now more studies devoted to the cryopreservation of tissues from which MSCs are derived. A new topic included in this review covers the application in COVID-19 of MSCs arising from their immunomodulatory and antiviral properties. Due to the inherent heterogeneity in MSC populations from different sources there is still no standardized procedure for their isolation, identification, functional characterization, cryopreservation, and route of administration, and not likely to be a "one-size-fits-all" approach in their applications in cell-based therapy and regenerative medicine.

Phytic Acid-Promoted Exfoliation of Black Phosphorus Nanosheets for the Fabrication of Photothermal Antibacterial Coatings

Medical device-associated infections (MDAI) caused by planktonic pathogens are of serious concern worldwide due to the emergence of drug resistance resulting from continuous overuse or misuse of antibiotics. Therefore, the design of non-antibiotics-based treatment for MDAI is of crucial importance. Black phosphorus (BP), a novel 2D material, has recently received much attention owing to its remarkable physical, chemical, mechanical, and functional features. However, the intricacy of the fabrication process has severely hampered the development of BP in prospective applications. In this study, a simple and eco-friendly liquid-phase exfoliation method of phytic acid (PA)-promoted exfoliation of BP nanosheets (PA@BP NSs) is developed for their potential application in antibacterial photothermal therapy. To impart the antimicrobial effects, the polydimethylsiloxane surfaces are functionalized with quaternized polymer (polyquaternium-2 or PQ) and PA@BP NSs, leading to the formation of PA-BP-PQ composite coatings. In addition to the contact-killing antibacterial effect of the cationic PQ, the PA-BP-PQ coating exhibits remarkable near-infrared irradiation-triggered bactericidal effects with low cytotoxicity both in vitro and in vivo. This study proposes a simple liquid-phase exfoliation technique for the fabrication of BP NSs and a one-step approach for the construction of PA-BP-PQ composite coatings for bi-modal (contact-killing and photothermal) antimicrobial therapy.

Nanotechnology-based theranostic and prophylactic approaches against SARS-CoV-2

SARS-CoV-2 (COVID-19) pandemic has been an unpredicted burden on global healthcare system by infecting over 700 million individuals, with approximately 6 million deaths worldwide. COVID-19 significantly impacted all sectors, but it very adversely affected the healthcare system. These effects were much more evident in the resource limited part of the world. Individuals with acute conditions were also severely impacted. Although classical COVID-19 diagnostics such as RT-PCR and rapid antibody testing have played a crucial role in reducing the spread of infection, these diagnostic techniques are associated with certain limitations. For instance, drawback of RT-PCR diagnostics is that due to degradation of viral RNA during shipping, it can give false negative results. Also, rapid antibody testing majorly depends on the phase of infection and cannot be performed on immune compromised individuals. These limitations in current diagnostic tools require the development of nanodiagnostic tools for early detection of COVID-19 infection. Therefore, the SARS-CoV-2 outbreak has necessitated the development of specific, responsive, accurate, rapid, low-cost, and simple-to-use diagnostic tools at point of care. In recent years, early detection has been a challenge for several health diseases that require prompt attention and treatment. Disease identification at an early stage, increased imaging of inner health issues, and ease of diagnostic processes have all been established using a new discipline of laboratory medicine called nanodiagnostics, even before symptoms have appeared. Nanodiagnostics refers to the application of nanoparticles (material with size equal to or less than 100 nm) for medical diagnostic purposes. The special property of nanomaterials compared to their macroscopic counterparts is a lesser signal loss and an enhanced electromagnetic field. Nanosize of the detection material also enhances its sensitivity and increases the signal to noise ratio. Microchips, nanorobots, biosensors, nanoidentification of single-celled structures, and microelectromechanical systems are some of the most modern nanodiagnostics technologies now in development. Here, we have highlighted the important roles of nanotechnology in healthcare sector, with a detailed focus on the management of the COVID-19 pandemic. We outline the different types of nanotechnology-based diagnostic devices for SARS-CoV-2 and the possible applications of nanomaterials in COVID-19 treatment. We also discuss the utility of nanomaterials in formulating preventive strategies against SARS-CoV-2 including their use in manufacture of protective equipment, formulation of vaccines, and strategies for directly hindering viral infection. We further discuss the factors hindering the large-scale accessibility of nanotechnology-based healthcare applications and suggestions for overcoming them.

Single-cell RNA sequencing to understand host-virus interactions

Single-cell RNA sequencing (scRNA-seq) has allowed for the profiling of host and virus transcripts and host-virus interactions at single-cell resolution. This review summarizes the existing scRNA-seq technologies together with their strengths and weaknesses. The applications of scRNA-seq in various virological studies are discussed in depth, which broaden the understanding of the immune atlas, host-virus interactions, and immune repertoire. scRNA-seq can be widely used for virology in the near future to better understand the pathogenic mechanisms and discover more effective therapeutic strategies.

2D/2D heterostructure Ni-Fe LDH/black phosphorus nanosheets with AuNP for noxious substance diphenylamine detection in food samples

In this study, gold nanoparticles decorated on nickel-iron layered double hydroxide with black phosphorus nanosheets (AuNP/Ni-Fe LDH/BPNSs) composite were prepared using a stirring method. Analyte tracing is required for developing viable sensors. The AuNP/Ni-Fe LDH/BPNSs composite exhibited a large specific surface area, high conductivity, high electrocatalytic activity, and rapid electron transfer. These properties play a vital role in monitoring diphenylamine (DPA) in food samples. The formation of the AuNP/Ni-Fe LDH/BPNSs composite was confirmed using various structural and morphological characterization techniques. The electroanalytical character of the AuNP/Ni-Fe LDH/BPNSs composite was evaluated using voltammetry. Interestingly, the AuNP/Ni-Fe LDH/BPNSs showed a wide linear range of 0.0125-1003.82 μM and a detection limit of 4.63 nM with a sensitivity of 0.399 µA µM-1 cm-2. The constructed sensor shows considerable selectivity, stability, repeatability, and reproducibility, and the practicability of DPA was monitored in the apples, sweet tomatoes, pears, and grapes with satisfactory recoveries.

Biomaterials for Drug Delivery and Human Applications

Biomaterials embody a groundbreaking paradigm shift in the field of drug delivery and human applications. Their versatility and adaptability have not only enriched therapeutic outcomes but also significantly reduced the burden of adverse effects. This work serves as a comprehensive overview of biomaterials, with a particular emphasis on their pivotal role in drug delivery, classifying them in terms of their biobased, biodegradable, and biocompatible nature, and highlighting their characteristics and advantages. The examination also delves into the extensive array of applications for biomaterials in drug delivery, encompassing diverse medical fields such as cancer therapy, cardiovascular diseases, neurological disorders, and vaccination. This work also explores the actual challenges within this domain, including potential toxicity and the complexity of manufacturing processes. These challenges emphasize the necessity for thorough research and the continuous development of regulatory frameworks. The second aim of this review is to navigate through the compelling terrain of recent advances and prospects in biomaterials, envisioning a healthcare landscape where they empower precise, targeted, and personalized drug delivery. The potential for biomaterials to transform healthcare is staggering, as they promise treatments tailored to individual patient needs, offering hope for improved therapeutic efficacy, fewer side effects, and a brighter future for medical practice.

Innovation and Patenting Activities During COVID-19 and Advancement of Biochemical and Molecular Diagnosis in the Post- COVID-19 Era

The COVID-19 pandemic is to escalate globally and acquire new mutations quickly, so accurate diagnostic technologies play a vital role in controlling and understanding the epidemiology of the disease. A plethora of technologies acquires diagnosis of individuals and informs clinical management of COVID. Some important biochemical parameters for COVID diagnosis are the elevation of liver enzymes, creatinine, and nonspecific inflammatory markers such as C-reactive protein (CRP) and Interleukin 6 (IL-6). The main progression predictors are lymphopenia, elevated D-dimer, and hyperferritinemia, although it is also necessary to consider LDH, CPK, and troponin in the marker panel of diagnosis. Owing to the greater sensitivity and accuracy, molecular technologies such as conventional polymerase chain reaction (PCR), reverse transcription (RT)-PCR, nested PCR, loop-mediated isothermal amplification (LAMP), and xMAP technology have been extensively used for COVID diagnosis for some time now. To make so many diagnostics accessible to general people, many techniques may be exploited, including point of care (POC), also called bedside testing, which is developing as a portable promising tool in pathogen identification. Some other lateral flow assay (LFA)-centered techniques like SHERLOCK, CRISPR-Cas12a (AIOD-CRISPR), and FNCAS9 editor limited uniform detection assay (FELUDA), etc. have shown auspicious results in the rapid detection of pathogens. More recently, low-cost sequencing and advancements in big data management have resulted in a slow but steady rise of next-generation sequencing (NGS)-based approaches for diagnosis that have potential relevance for clinical purposes and may pave the way toward a better future. Due to the COVID-19 pandemic, various institutions provided free, specialized websites and tools to promote research and access to critically needed advanced solutions by alleviating research and analysis of data within a substantial body of scientific and patent literature regarding biochemical and molecular diagnosis published since January 2020. This circumstance is unquestionably unique and difficult for anyone using patent information to find pertinent disclosures at a specific date in a trustworthy manner.

Development of biosensors for detection of fibrinogen: a review

Fibrinogen as a major inflammation marker and blood coagulation factor has a direct impact on the health of humanity. The variations in fibrinogen content lead to risky conditions such as bleeding and cardiovascular diseases. So, accurate methods for monitoring of this glycoprotein are of high importance. The conventional methods, such as the Clauss method, are time consuming and require highly specialized expert analysts. The development of fast, simple, easy to use, and inexpensive methods is highly desired. In this way, biosensors have gained outstanding attention since they offer means for performing analyses at the points-of-care using self-testing devices, which can be applied outside of clinical laboratories or hospital. This review indicates that different electrochemical and optical sensors have been successfully implemented for the detection of fibrinogen under normal levels of fibrinogen in plasma. The biosensors for the detection of fibrinogen have been designed based on the quartz crystal microbalance, field-effect transistor, electrochemical impedance spectroscopy, amperometry, surface plasmon resonance, localized surface plasmon resonance, and colorimetric techniques. Also, this review demonstrates the utility of the application of nanoparticles in different detection techniques.

Recent Advances in Phosphorene: Structure, Synthesis, and Properties

Phosphorene is a 2D phosphorus atomic layer arranged in a honeycomb lattice like graphene but with a buckled structure. Since its exfoliation from black phosphorus in 2014, phosphorene has attracted tremendous research interest both in terms of synthesis and fundamental research, as well as in potential applications. Recently, significant attention in phosphorene is motivated not only by research on its fundamental physical properties as a novel 2D semiconductor material, such as tunable bandgap, strong in-plane anisotropy, and high carrier mobility, but also by the study of its wide range of potential applications, such as electronic, optoelectronic, and spintronic devices, energy conversion and storage devices. However, a lot of avenues remain to be explored including the fundamental properties of phosphorene and its device applications. This review recalls the current state of the art of phosphorene and its derivatives, touching upon topics on structure, synthesis, characterization, properties, stability, and applications. The current needs and future opportunities for phosphorene are also discussed.

Advances in Stem Cell-Based Therapies in the Treatment of Osteoarthritis

Osteoarthritis (OA) is a chronic, degenerative joint disease presenting a significant global health threat. While current therapeutic approaches primarily target symptom relief, their efficacy in repairing joint damage remains limited. Recent research has highlighted mesenchymal stem cells (MSCs) as potential contributors to cartilage repair, anti-inflammatory modulation, and immune regulation in OA patients. Notably, MSCs from different sources and their derivatives exhibit variations in their effectiveness in treating OA. Moreover, pretreatment and gene editing techniques of MSCs can enhance their therapeutic outcomes in OA. Additionally, the combination of novel biomaterials with MSCs has shown promise in facilitating the repair of damaged cartilage. This review summarizes recent studies on the role of MSCs in the treatment of OA, delving into their advantages and exploring potential directions for development, with the aim of providing fresh insights for future research in this critical field.

Ceria-Based Nanozymes in Point-of-Care Diagnosis: An Emerging Futuristic Approach for Biosensing

In recent years, there has been a notable increase in interest surrounding nanozymes due to their ability to imitate the functions and address the limitations of natural enzymes. The scientific community has been greatly intrigued by the study of nanoceria, primarily because of their distinctive physicochemical characteristics, which include a variety of enzyme-like activities, affordability, exceptional stability, and the ability to easily modify their surfaces. Consequently, nanoceria have found extensive use in various biosensing applications. However, the impact of its redox activity on the enzymatic catalytic mechanism remains a subject of debate, as conflicting findings in the literature have presented both pro-oxidant and antioxidant effects. Herein, we creatively propose a seesaw model to clarify the regulatory mechanism on redox balance and survey possible mechanisms of multienzyme mimetic properties of nanoceria. In addition, this review aims to showcase the latest advancements in this field by systematically discussing over 180 research articles elucidating the significance of ceria-based nanozymes in enhancing, downsizing, and enhancing the efficacy of point-of-care (POC) diagnostics. These advancements align with the ASSURED criteria established by the World Health Organization (WHO). Furthermore, this review also examines potential constraints in order to offer readers a concise overview of the emerging role of nanoceria in the advancement of POC diagnostic systems for future biosensing applications.

Faradaic Impedimetric Immunosensor for Label-Free Point-of-Care Detection of COVID-19 Antibodies Using Gold-Interdigitated Electrode Array

Label-free electrochemical biosensors have many desirable characteristics in terms of miniaturization, scalability, digitization, and other attributes associated with point-of-care (POC) applications. In the era of COVID-19 and pandemic preparedness, further development of such biosensors will be immensely beneficial for rapid testing and disease management. Label-free electrochemical biosensors often employ [Fe(CN)6]-3/4 redox probes to detect low-concentration target analytes as they dramatically enhance sensitivity. However, such Faradaic-based sensors are reported to experience baseline signal drift, which compromises the performance of these devices. Here, we describe the use of a mecaptohexanoic (MHA) self-assembled monolayer (SAM) modified Au-interdigitated electrode arrays (IDA) to investigate the origin of the baseline signal drift, developed a protocol to resolve the issue, and presented insights into the underlying mechanism on the working of label-free electrochemical biosensors. Using this protocol, we demonstrate the application of MHA SAM-modified Au-IDA for POC analysis of human serum samples. We describe the use of a label-free electrochemical biosensor based on covalently conjugated SARS-CoV-2 spike protein for POC detection of COVID-19 antibodies. The test requires a short incubation time (10 min), and has a sensitivity of 35.4/decade (35.4%/10 ng mL-1) and LOD of 21 ng/mL. Negligible cross reactivity to seasonal human coronavirus or other endogenous antibodies was observed. Our studies also show that Faradaic biosensors are ~17 times more sensitive than non-Faradaic biosensors. We believe the work presented here contributes to the fundamental understanding of the underlying mechanisms of baseline signal drift and will be applicable to future development of electrochemical biosensors for POC applications.

Biodegradable nano black phosphorus based SDF1-α delivery system ameliorates Erectile Dysfunction in a cavernous nerve injury rat model by recruiting endogenous stem/progenitor cells

Stem cell (SC) therapy has been shown high prospects in erectile dysfunction (ED) treatment. Without ethical issues and risks of immune rejection and tumorigenesis of exogenous SC therapy, endogenous stem/progenitor cells (S/PCs) have a better potential for ED management, and their homing and redistribution are controlled by SDF1-α/CXCR4 axis. Considering black phosphorus nanosheet (BPNS) has emerged as an efficient and safe drug vehicle due to its large surface area, biodegradability, and the ability to retain and slowly release its loaded drugs, BPNS is utilized to load SDF1-α, a chemokine for S/PCs, to construct the BP@SDF1-α complex to efficiently recruit stem cells (SCs) by injury-site injection and thus ameliorate ED within the bilateral cavernous nerve injury (BCNI) rat models. We find that BP@SDF1-α can efficiently recruit exogenous SCs and endogenous S/PCs to corpus cavernosum and main pelvic ganglion (MPG) by local administration. Of note, ascribing to endogenous S/PCs recruitment, it also successfully alleviates ED in BCNI rat models by enhancing the protein expression levels of α-SMA, CD31, and nNOs, and eliciting less collagen deposition in the penis after its combined injection at corpus cavernosum and MPG. Thus, this study provides a new insight into the treatment of ED with endogenous S/PCs. BIODEGRADABLE NANO BLACK PHOSPHORUS BASED SDF1-α DELIVERY SYSTEM AMELIORATES ERECTILE DYSFUNCTION IN A CAVERNOUS NERVE INJURY RAT MODEL BY RECRUITING ENDOGENOUS STEM/PROGENITOR CELLS.

Enhanced Osteocyte Differentiation: Cathepsin D and L Secretion by Human Adipose-Derived Mesenchymal Stem Cells

Adipose-derived mesenchymal stem cells (ASCs) have the potential to differentiate into bone, cartilage, fat, and neural cells and promote tissue regeneration and healing. It is known that they can have variable responses to hypoxic conditions. In the present study, we aimed to explore diverse changes in the cells and secretome of ASCs under a hypoxic environment over time and to present the possibility of ASCs as therapeutic agents from a different perspective. The expression differences of proteins between normoxic and hypoxic conditions (6, 12, or 24 h) were specifically investigated in human ASCs using 2-DE combined with MALDI-TOF MS analysis, and secreted proteins in ASC-derived conditioned media (ASC-derived CM) were examined by an adipokine array. In addition, genetic and/or proteomic interactions were assessed using a DAVID and miRNet functional annotation bioinformatics analysis. We found that 64 and 5 proteins were differentially expressed in hypoxic ASCs and in hypoxic ASC-derived CM, respectively. Moreover, 7 proteins among the 64 markedly changed spots in hypoxic ASCs were associated with bone-related diseases. We found that two proteins, cathepsin D (CTSD) and cathepsin L (CTSL), identified through an adipokine array independently exhibited significant efficacy in promoting osteocyte differentiation in bone-marrow-derived mesenchymal stem cells (BM-MSCs). This finding introduces a promising avenue for utilizing hypoxia-preconditioned ASC-derived CM as a potential therapeutic approach for bone-related diseases.

Through the looking glass: attempting to predict future opportunities and challenges in experimental biology

To celebrate its centenary year, Journal of Experimental Biology (JEB) commissioned a collection of articles examining the past, present and future of experimental biology. This Commentary closes the collection by considering the important research opportunities and challenges that await us in the future. We expect that researchers will harness the power of technological advances, such as '-omics' and gene editing, to probe resistance and resilience to environmental change as well as other organismal responses. The capacity to handle large data sets will allow high-resolution data to be collected for individual animals and to understand population, species and community responses. The availability of large data sets will also place greater emphasis on approaches such as modeling and simulations. Finally, the increasing sophistication of biologgers will allow more comprehensive data to be collected for individual animals in the wild. Collectively, these approaches will provide an unprecedented understanding of 'how animals work' as well as keys to safeguarding animals at a time when anthropogenic activities are degrading the natural environment.

Innovative Phosphorene Nanoplatform for Light Antimicrobial Therapy

Over the past few years, antibiotic resistance has reached global dimensions as a major threat to public health. Consequently, there is a pressing need to find effective alternative therapies and therapeutic agents to combat drug-resistant pathogens. Photodynamic therapy (PDT), largely employed as a clinical treatment for several malignant pathologies, has also gained importance as a promising antimicrobial approach. Antimicrobial PDT (aPDT) relies on the application of a photosensitizer able to produce singlet oxygen (1O2) or other cytotoxic reactive oxygen species (ROS) upon exposure to appropriate light, which leads to cell death after the induced photodamage. Among different types of 2D nanomaterials with antimicrobial properties, phosphorene, the exfoliated form of black phosphorus (bP), has the unique property intrinsic photoactivity exploitable for photothermal therapy (PTT) as well as for PDT against pathogenic bacteria.

Positive effects of hypoxic preconditioning of the extracellular matrix and stromal vascular fraction from adipose tissue

Background

Numerous approaches have been developed to decelerate the aging process of facial skin. Synthetic fillers and cell-enriched fat grafts are the main procedures employed to fill wrinkles.

Objective

The aim of this study was to evaluate the in vitro and in vivo safety and efficiency of a new process developed by SYMBIOKEN: the AmeaCell, which facilitates the extraction of the stromal vascular fraction (SVF) and the associated hypoxia pre-conditioned matrix to promote fat graft survival.

Methods

The AmeaCell device allows the extraction from adipose tissue of SVF and pre-conditioned MatriCS and promotes a hypoxic environment. Experiments were carried out on human cells and then in mice.

Results

Characterization of cells and MatriCS showed that after their extraction using the new process developed by SYMBIOKEN, the extracted cells expressed stem-cell markers. The presence of characteristic proteins and lipid fractions found in the adipose matrix were confirmed in MatriCS. Cobalt chloride treatment of the matrix using the AmeaCell device induced modifications in the matrix composition with a decrease in laminin and without collagen modification, both of which promote adhesion and differentiation of SVF or adipose-derived stromal cells. The combination of MatriCS and SVF (1 × 106 and 5 × 106, respectively) is safe and efficient to fill winkles induced by UVB irradiation. The cross-talk between MatriCS and SVF can act a durable filler compared to the filling performed using cells or matrix or fat alone, which need to be replaced frequently.

Conclusion

These results indicate that the combination of MatriCS and SVF is safe and effective as a biological filler for achieving skin rejuvenation and wrinkle filling.