Tissue repair and regeneration have long been a focus of research, with growing evidence highlighting the role played by immunomodulation. The repair of tissue cells can be significantly promoted through the localized immunomodulation of tissues. Hydrogels are increasingly used in this field due to their biocompatibility, versatility, and relative ease of fabrication. This Review highlights the critical role of inflammation and immune development in the complex process of tissue repair after injury, highlighting the dynamic interactions between immune cells that ultimately influence the outcome of tissue healing. We also summarize the precise functions of immune cells and their responses in various tissue injury scenarios, which are critical for harnessing the full potential of immunomodulatory strategies to promote tissue repair. We discuss recent advances in drug-carrying hydrogels, which offer promising avenues for tissue regeneration with precise control of the immune environment for constructive tissue repair. Further advances in our understanding of the mechanisms driving inflammation and immune cell behavior during tissue injury are expected to foster the development of increasingly effective hydrogel-based immunomodulatory strategies to promote tissue repair and regeneration.
The ultrasound guidance of cryotherapy could be improved if changes of tissue characterization parameters during freezing could be used to monitor freezing patterns and estimate the postoperative effects after surgery.The ultrasonic integrated backscatter analysis holds promise as an effective method for signal analysis and characterization of thawed tissues.The ultrasonic integrated backscatter has been found to be an important parameter for describing the ultrasonic scattering and characterization of biological tissues. However, its potential values in the evaluation of cryosurgical effects of tissues reserved unclear so far. Here, we investigated the power spectrum of acoustic signal to estimate the ultrasound integrated backscatter in normal and freeze-thawed tissues on porcine livers in vitro.The experimental results carried out at 10 MHz using weakly focused pulse-echo signal element transducer indicated that the ultrasonic integrated backscatter in normal liver tissues is 31.3±4.6 whereas it is 44.2±6.5 in several pre-frozen and then thawed tissues.These results disclosed the good correlation between the ultrasonic integrated backscatter and microstructures of the normal or thawed tissues, and hence demonstrated that the power spectrum holds promise to be used as an effective method for the characterization of thawed tissues ultrasonic integrated backscatter, which might offer a potential pragmatic prospect for the practice of monitoring transition zone between frozen and unfrozen tissues during the surgical therapy, and evaluating postoperative effects.
Abstract Background Cardiac conduction disease (CCD) and sick sinus syndrome (SSS) may be related to a degenerative process. Leukocyte telomere length (LTL) is associated with the aging process and age-related degenerative diseases. We aimed to investigate the association between LTL and the risks of CCD/SS, and to explore whether LTL is related with cardiovascular imaging and electrocardiographic (ECG) changes. Methods This is a population-based cross-sectional study of UK Biobank participants without history of CCD/SSS recruited from 2006 to 2010. LTL was measured using a quantitative polymerase chain reaction method. Cardiovascular measurements were derived from cardiovascular magnetic resonance using machine learning. The median (IQR) duration of follow-up was 12.0 (11.3-12.7) years. The associations of LTL with imaging and ECG measurements and incident CCD/SSS were evaluated by multivariable regression models. Results Among the 412,452 white participants, 188,891 (45.8%) were male, with a mean age of 57.3 years. Longer LTL was independently associated with positive cardiac remodeling, including higher left ventricular mass, larger atrial volume, and increased atrial stroke volumes. However, no significant associations were observed with ECG findings including PR interval and P-wave duration. 11991 (2.6%) participants developed CCD and 984 (0.2%) developed SSS. Longer LTL was not associated with younger age. However, longer LTL was not associated with a lower risk of incident CCD (LTL fourth quartile vs. first quartile: hazard ratio, 0.98; 95% CI, 0.97-1.0; P = 0.057) or SSS (LTL fourth quartile vs. first quartile: hazard ratio, 0.98; 95% CI, 0.92-1.05; P = 0.554). Conclusions In this cross-sectional study, longer LTL was associated with a larger atrial size with better atrial function in middle age, but not with ECG changes. However, longer LTL was not associated with a lower risk of incident CCD and SSS.
Abstract Background Sick sinus syndrome (SSS) and atrial fibrillation (AF) often coexist, demonstrating a bidirectional relationship. The polygenic risk score (PRS) represents the cumulative risk of disease onset based on variations at multiple genetic loci and is known as a predictor for disease incidence. However, the PRS for SSS remains under-investigated. This study aims to evaluate whether the PRS for AF can predict the incidence of SSS in the general population. Methods The UK biobank, comprising of about 500,000 participants aged 40 to 70, was established across 22 centres in the UK between 2006 and 2010. After excluding missing values, prior AF history, and valvular heart disease, a total of 101,654 participants without AF (median age, 56.0 [interquartile range (IQR), 49.0–63.0] years; 44,851 [44.1%] male) were analyzed. Participants were divided into quartiles according to a validated PRS for AF. Throughout the observation period, the incidence of SSS event was documented. Results During a follow-up period of 11.7 (IQR 11.0-12.5) years, a total of 157 cases of Sick sinus syndrome were identified. In the new-onset SSS group, age, PRS for AF, BMI, and waist measurements were significantly higher. Additionally, there was a statistically significant increase in the proportions of male sex, hypertension, previous MI, hypothyroidism, dyslipidemia, and ESRD/CKD. The Kaplan-Meier analysis demonstrated an association between the highest quartile and an increased incidence of SSS compared to the other quartiles. (Log-rank P < 0.001) The Cox regression model revealed that a PRS for AF was associated with an increased risk of incidence of sick sinus syndrome (aHR 1.29, 95% CI 1.10-1.51, p-value 0.002). Notably, the discriminative power of our model was substantial, yielding a C-index of 0.746. Conclusion In our study, the PRS for AF effectively predicted the incidence of SSS. In the absence of a dedicated PRS for SSS, the AF PRS may offer insights into developing one for SSS.
Abstract This paper describes an on-chip configurable Digital to Analog Converter (DAC) module for monolithic active pixel sensor. The DAC module consists of four 10-bit voltage DACs, seven 8-bit current DACs, a bandgap circuit, and a configure interface. The voltage DAC is implemented with an R-2R resistor ladder network, and each LSB corresponds to 3 mV. The current DAC is in the current-steering type with a thermometer code. Each LSB of the current DAC corresponds to 10 nA. The bandgap circuit provides a stable, temperature-independent reference voltage of 1.25 V to the DACs. All the DACs can be accessed and configured with the configure interface. The DAC module covers 3074 µm × 400 µm, and the total power consumption is 46.2 mW. This paper will discuss the design and performance of this DAC module.
The field of infected wound management continues to face challenges, and traditional methods used to cope with wounds include debridement, gauze coverage, medication, and others. Currently, synthetic and natural biomaterials are readily available today, enabling the creation of new wound dressings that substantially enhance wound healing. Considerable attention is being paid to hydrogels based on natural materials, which have good biocompatibility and degradability properties, while exhibiting higher similarity to natural extracellular matrix as compared to synthetic materials. In this study, we extracted the active ingredients of oxidized konjac glucomannan (OKGM) and fresh egg white (EW) from 2 foods, konjac, and egg, respectively, and formed a self-repairing hydrogel based on the cross-linking of a Schiff base. Subsequently, a natural active peptide, glycyl-l-histidyl-l-lysine-Cu (GHK-Cu), was loaded, and an all-natural composite hydrogel dressing, EW/OKGM@GHK-Cu (GEK), was developed. The GEK hydrogel, exhibiting both antibacterial and anti-inflammatory properties, plays a hemostatic role by adhering to tissues and promoting neovascularization and serves as an optimal dressing for skin regeneration. Taken together, GEK hydrogel dressings derived from natural food sources therefore constitute an efficient and cost-effective strategy for managing infected wound healing and have significant potential for clinical application and transformation.
Deoxyribonucleotide (DNA) is uniquely programmable and biocompatible, and exhibits unique appeal as a biomaterial as it can be precisely designed and programmed to construct arbitrary shapes. DNA hydrogels are polymer networks comprising cross-linked DNA strands. As DNA hydrogels present programmability, biocompatibility, and stimulus responsiveness, they are extensively explored in the field of biomedicine. In this study, we provide an overview of recent advancements in DNA hydrogel technology. We outline the different design philosophies and methods of DNA hydrogel preparation, discuss its special physicochemical characteristics, and highlight the various uses of DNA hydrogels in biomedical domains, such as drug delivery, biosensing, tissue engineering, and cell culture. Finally, we discuss the current difficulties facing DNA hydrogels and their potential future development.