Zhao Chen

Conventional wound dressings present inherent limitations in the therapeutic management of cutaneous wounds. Given the pivotal role of endogenous bioelectric fields in tissue repair, piezoelectric materials have emerged as a novel class of stimulus responsive biomaterials capable of transforming mechanical energy into biocompatible electrical signals, offering innovative solutions to address the bottlenecks of conventional interventions. Distinct from existing literature, this review demonstrates significant uniqueness by integrating the dual dimensions of breadth and depth. In terms of breadth, this review comprehensively covers and systematically categorizes a wide variety of piezoelectric dressing systems alongside their diverse stimulus responsive behaviors. In terms of depth, it not only profoundly elucidates the physical and chemical mechanisms underlying the piezoelectric effect and piezocatalysis, but also meticulously explores the key biological mechanisms through which they modulate multidimensional cellular behaviors and exert antibacterial effects. Building upon this foundation, the review systematically summarizes the current frontier application achievements of utilizing piezoelectric technologies for wound management. Finally, this review summarizes the major technical challenges and clinical translation bottlenecks facing piezoelectric dressings, and proposes highly promising future research directions, aiming to establish a solid theoretical framework and practical guidance for the development of piezoelectric wound management systems.

Background: Wound management is a critical component of clinical practice. Promoting timely healing of wounds is essential for patient recovery. Traditional treatments have limited efficacy due to prolonged healing times, excessive inflammatory responses, and susceptibility to infection. Methods: In this research, we created an injectable hydrogel wound dressing formulated from gelatin methacryloyl (GelMA) that encapsulates quercetin-loaded zeolitic imidazolate framework-8 (Qu@ZIF-8) nanoparticles. Next, its ability to promote skin wound healing was validated through in vitro experiments and animal studies. Results: Research conducted both in vitro and in vivo indicated that this hydrogel dressing effectively mitigates inflammation, inhibits bacterial growth, and promotes angiogenesis and collagen synthesis, thus facilitating a safe and efficient healing process for wounds. Conclusions: This cutting-edge scaffold system provides a novel strategy for wound repair and demonstrates significant potential for clinical applications.

By tuning the surface properties, biomaterials can precisely manipulate the osteoimmune environment favoring bone regeneration.

Cell-based tissue engineering is one of the optimistic approaches to replace current treatments for bone defects. Urine-derived stem cells (USCs) are obtained non-invasively and become one of the promising seed cells for bone regeneration. An injectable BMP2-releasing chitosan microspheres/type I collagen hydrogel (BMP2-CSM/Col I hydrogel) was fabricated. USCs proliferated in a time-dependent fashion, spread with good extension and interconnected with each other in different hydrogels both for 2D and 3D models. BMP2 was released in a sustained mode for more than 28 days. Sustained-released BMP2 increased the ALP activities and mineral depositions of USCs in 2D culture, and enhanced the expression of osteogenic genes and proteins in 3D culture. In vivo, the mixture of USCs and BMP2-CSM/Col I hydrogels effectively enhanced bone regeneration, and the ratio of new bone volume to total bone volume was 38% after 8 weeks of implantation. Our results suggested that BMP2-CSM/Col I hydrogels promoted osteogenic differentiation of USCs in 2D and 3D culture in vitro and USCs provided a promising cell source for bone tissue engineering in vivo. As such, USCs-seeded hydrogel scaffolds are regarded as an alternative approach in the repair of bone defects.

Background: To systematically review the literature and provide a comprehensive understanding of the preemptive effects of oral pregabalin on perioperative pain management in lower limb orthopedic surgery. Method: We searched three electronic databases for randomized controlled trials comparing the results of preoperative pregabalin and placebo in patients undergoing lower limb orthopedic surgery. Data analyses were conducted using RevMan 5.4. Results: Twenty-one randomized controlled trials met our inclusion criteria. The cumulative opioid consumption within 24 and 48 h postoperatively in the pregabalin group was significantly less than that in the placebo group. The pooled static pain intensity at all time points within the first day was significantly lower in the pregabalin group than in the placebo group. Lower dynamic pain intensity at 48 h was detected in the pregabalin group than in the placebo group. Meanwhile, pregabalin led to a lower incidence of nausea but appeared to be associated with a higher incidence of dizziness and sedation. Subgroup analyses showed that no difference was detected between subgroups stratified by dosing regimen or pregabalin dose in the results of opioid consumption, pain intensity and incidence of complications. Conclusion: This meta-analysis supports the use of pregabalin preoperatively in patients undergoing lower limb orthopedic surgery. However, it was wary of the resulting increase in dizziness and sedation. There is no evidence to support the continued use of pregabalin postoperatively or using more than 150 mg of pregabalin per day. Trial registration: This study was registered on 09 November 2021 with INPLASY (registration number: INPLASY2021110031).

Purpose To estimate the prevalence of depression in degenerative spine disease (DSD) patients. Methods The PubMed, EMBASE, and PsycINFO were systematically searched, the relevant studies that reported the depression prevalence of in DSD patients were identified. Data were extracted independently by 2 reviewers. Subgroup analysis and sensitivity analysis were also performed. Results 24 articles met the inclusion criteria and were selected for the current study. The pooled prevalence estimate of depression in DSD patients before operative treatment was 30.8% [95% CI 24.0–38.5%]. Nine articles reported the prevalence rate in DSD patients after operative treatment, and the pooled prevalence estimate was 27.0% [95% CI 19.9–35.4%]. There were significant differences for prevalence estimates before operative treatment in types of disorders (Q = 4.56, P = 0.10), spine surgery history (Q = 5.55, P = 0.02), representativeness of sample (Q = 11.00, P = 0.00), and validity of assessment method (Q = 3.32, P = 0.07). The prevalence estimates in patients with lumbar spine stenosis, lumbar disc herniation and cervical spondylotic myelopathy were 24.0%, 40.9% and 37.3%, respectively. Studies that included patients with a history of spine surgery yielded a more extreme prevalence estimate than studies excluding those (36.9% vs 24.3%). For results of patients after operative treatment, significant differences for prevalence estimates were showed in different degrees of pain (Q = 4.72, P = 0.03), screening instruments (Q = 4.83, P = 0.09), and representativeness of sample (Q = 15.70, P = 0.00). Conclusion The systematic review indicated increased prevalence of depression in DSD patients. In consideration of the relationship between depression and poor surgical outcome, we should pay more attention to identifying strategies for preventing and treating depression in DSD patients.

Cervical spondylotic myelopathy (CSM) is a common disease of the elderly that is characterized by gait instability, sensorimotor deficits, etc. Recurrent symptoms including memory loss, poor attention, etc. have also been reported in recent studies. However, these have been rarely investigated in CSM patients. To investigate the cognitive deficits and their correlation with brain functional alterations, we conducted resting-state fMRI (rs-fMRI) signal variability. This is a novel indicator in the neuroimaging field for assessing the regional neural activity in CSM patients. Further, to explore the network changes in patients, functional connectivity (FC) and graph theory analyses were performed. Compared with the controls, the signal variabilities were significantly lower in the widespread brain regions especially at the default mode network (DMN), visual network, and somatosensory network. The altered inferior parietal lobule signal variability positively correlated with the cognitive function level. Moreover, the FC and the global efficiency of DMN increased in patients with CSM and positively correlated with the cognitive function level. According to the study results, (1) the cervical spondylotic myelopathy patients exhibited regional neural impairments, which correlated with the severity of cognitive deficits in the DMN brain regions, and (2) the increased FC and global efficiency of DMN can compensate for the regional impairment.

Study Design.: Cross-sectional study. Objective: To analyze altered functional connectivity (FC) in the visual cortex of cervical spondylotic myelopathy (CSM) patients using resting-state functional magnetic resonance imaging (fMRI). Summary of Background Data.: We previously showed changes in visual cortex neural activity in CSM patients. Methods.: Thirty CSM patients and 20 healthy controls were recruited. MR data were collected using a 3.0 T MR. FC of the regions of interest (ROI) (Brodmann areas [BA] 17/18/19/7) were calculated in a voxel-wise manner and compared between groups. Correlation analyses were performed between preoperative Japanese Orthopaedic Association (JOA) scores and altered FC, as well as between preoperative best corrected visual acuity (BCVA) and altered FC. Furthermore, the FC where was compared between the preoperative and the postoperative CSM patients in an ROI-wise manner. Results.: Increased FC was found between BA19 and the cerebellum inferior lobe; between the left BA7 and bilateral calcarine, right lingual, right fusiform gyrus, and left precuneus (BA17); between the left BA7 and right fusiform gyrus and right inferior occipital gyrus (right BA19); and between the right BA7 and right superior lobe of cerebellum (right BA19) in CSM patients (P < 0.05). A negative correlation was found between JOA score and FC of the left and right BA19, and a positive correlation was found between the BCVA and FC of the left and right BA7 (P < 0.05). ROI analysis demonstrated statistically significant FC differences in between the preoperative and the postoperative CSM patients (P < 0.05). Conclusion.: FC changes were present in the visual cortex of CSM patients, which negatively correlated with preoperative JOA scores and positively correlated with preoperative BCVA. Significant recovery of FC in the visual cortex was detected in CSM patients postoperatively. Level of Evidence: 4