Frontiers in medical technology最新文献

The extracellular matrix (ECM) serves as a dynamic biological framework that orchestrates cellular behavior through biomechanical and biochemical cues, playing a pivotal role in tissue homeostasis and repair. Despite significant advancements in biomaterial design, current regenerative strategies often fail to fully replicate the ECM's complexity, leading to suboptimal healing outcomes. This review comprehensively examines ECM biology and its application in biomaterial engineering, highlighting structural-functional relationships, integrin-mediated signaling, and ECM remodeling mechanisms in wound healing. We analyze diverse biomaterial classes-including ECM-based scaffolds, synthetic polymers, natural biomaterials, bioceramics, and composites-focusing on their design principles, fabrication techniques, degradation profiles, and clinical applications. Key challenges such as immunogenicity, vascularization, mechanical mismatch, and regulatory hurdles are critically evaluated. Innovations in decellularization, biofunctionalization, and advanced manufacturing (e.g., 3D bioprinting, electrospinning) are discussed as promising avenues to enhance biomimicry and therapeutic efficacy. Furthermore, we explore clinically approved ECM-derived products and underscore the need for standardized protocols to bridge translational gaps. By integrating emerging research with clinical perspectives, this review provides a roadmap for developing next-generation ECM-inspired biomaterials that address unmet needs in regenerative medicine, emphasizing interdisciplinary collaboration to optimize safety, functionality, and patient outcomes.

Medical science is striving to find new solutions to treat various diseases. Tissue engineering with a great potential to develop tissues and even organs from synthetic and biological materials, open a new gate toward absolute treatments. Although in tissue engineering as a subtype of regenerative medicine, decellularized tissues are new, promising way to fill the previous methods gaps. Outside of the biological aspects, artificial intelligence (AI) and machine learning (ML) are applied to tissue engineering. Decellularization is a very important area where AI supports protocols and ensures the process is repeated identically each time. It also greatly assists in monitoring the extracellular matrix (ECM) to ensure it remains intact. Nonetheless, the use of AI in tissue engineering is not fully discussed in scientific articles. Although based on the tissue used for decellularization these features could vary, to optimize decellularization we need new method to reach high accuracy. In these current days, Pericardium, a double-layered membrane around the heart of mammalians, as a natural ECM has been utilized in cardiac surgery for many years. However, the use of decellularized pericardium as a scaffold for tissue engineering has gained significant attention in recent times, due to its retention strength, flexibility, supports for cell growth and differentiation, etc. That altogether put it among the top choices for tissue engineering and regenerative medicine. In this review we aim to cover the different decellularization methods, application of decellularized pericardium, commercial products that are available and challenges and future direction of this potent therapy.

Introduction: Warm ischemia during kidney transplantation contributes to graft dysfunction. External cooling devices have been developed to preserve graft during anastomosis, with promising results in experimental models. A systematic review and meta-analysis were conducted to evaluate the effectiveness of renal cooling devices.

Methods: A comprehensive search of seven databases was performed from inception to January 6, 2023. Eligible studies were randomized, prospective, and included a control group. Four studies met the inclusion criteria. The protocol was registered in PROSPERO (CRD42023409480).

Results: All studies reported significantly lower reperfusion temperatures in kidneys treated with cooling devices compared to controls. Histological graft injury, showed no statistically significant difference (SMD -0.95; 95% CI -10.74 to 8.83). However, post-transplant urinary output was significantly higher in the cooling device groups (SMD 0.49; 95% CI 0.10 to 0.88).

Discussion: The overall risk of bias across included studies was high. Cooling devices effectively lower graft temperature and may improve early functional outcomes. However, evidence of histological benefit remains inconclusive. Further clinical trials are needed to confirm efficacy and standardize device implementation in human transplantation.

Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD42023409480, PROSPERO CRD42023409480.

Introduction: Preterm infants' growth is typically monitored through weight, body length (BL) and head circumference (HC). However, 3D cranial volume (CrV) is considered a more accurate indicator of brain growth than 2D HC. The PreemieScanner is a novel 3D measuring device that simultaneously measures BL, HC and CrV. Its clinical usability was tested in a simulated NICU setting.

Materials and methods: Three extremely low birth weight (ELBW; BW < 1,000 gram) dolls with Optiflow breathing systems, (tubes positioned either at the front or back of the head) were used. Nurses conducted scan sessions and marked anatomical landmarks on 3D PreemieScanner images. As control, nurses measured HC manually with a standard measuring tape. Key outcomes were: (1) Measurement success rate, (2) Precision-percentage within clinically allowed limits, ±0.4 cm for BL, ±0.3 cm for HC, ±12 ml for CrV, and 3) accuracy-mean or median measurement error (MME) relative to the ground truth.

Results: Thirty-five scan sessions resulted in 100% successful measurements for BL and HC; 80% for CrV. BL MME -3.3% (p < 0.001); 40% (42/105) within precision limits. HC MME (Optiflow-front) 0.0% (p = 0.63); 89% (51/57) within limits. HC MME (Optiflow-back) -0.4% (p = 0.91). 93% (43/46) within limits. MME HC measuring tape, (Optiflow-front) -0.8% (p < 0.001), 88% (50/57) within limits, and MME (Optiflow-back) -1.1% (p < 0.001), 83% (40/48) within limits. MME CrV (Optiflow-front) -1.8% (p = 0.01), 86% (31/36) within limits, MME CrV (Optiflow-back) -1.3% (p < 0.001), 98% (45/46) within limits.

Conclusions: The PreemieScanner is a reliable, comprehensive device for measuring BL, HC and CrV in ELBW infants. It integrates smoothly into routine care with minimal disturbance. HC measurements demonstrated higher accuracy and precision than traditional tape method. CrV measurements, with 93% within precision limits, can be regarded as acceptable, enabling development of CrV growth reference charts, enhancing clinical growth monitoring.

Background: Identification of coronary ischemia in suspected coronary artery disease (CAD) remains challenging. Magnetocardiography (MCG) demonstrated comparably high diagnostic efficiency for detecting coronary ischemia in previous studies. However, limited evidence exists comparing MCG vs. computed tomography angiography-derived fractional flow reserve (CTFFR) in suspected CAD patients.

Methods: A total of 291 patients with CTA-confirmed diameter stenosis ranging from 30% to 90% were included and divided into two groups based on the CTFFR values, the stable coronary artery disease (SCAD) group (≤0.8) and the non-SCAD group (>0.8). Magnetic field map (MFM) parameters were employed to construct a diagnostic model. The performance of the models was evaluated using receiver operating characteristic (ROC) curves, accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

Results: Patients with SCAD showed a mean MCG score of 5.6 ± 2.9, while the non-SCAD group demonstrated a mean score of 2.0 ± 1.9 (P < 0.001). The area under the curve (AUC) for ROC analysis was 0.824 (95% CI: 0.772-0.877). Point 5 was selected as the operational cutoff value providing a favorable balance of sensitivity and specificity. Ultimately, MCG score yielded a sensitivity of 69.6%, specificity of 87.9%, PPV of 72.7%, NPV of 86.2%, and accuracy of 82.1%.

Conclusions: Compared to CTFFR, MCG demonstrated superior specificity and moderate sensitivity for detecting CAD in patients with diameter stenosis CTA ranging from 30% to 90%. It may provide an alternative to functional evaluation prior to invasive or radiation exposure methods.

Purpose: This study evaluates the primary hypothesis of red cell mass (RCM) dependent amplitude of homeostatically acceptable limits of fluctuation in plasma dilution by exploring the correlation between RCM-specific equilibrated hematocrit (EQ_Hct) and amplitude of plasma dilution during perioperative mini Volume Loading Test (mVLT).

Materials and methods: We retrospectively analyzed data from our previous RCTs, including 1,651 invasive arterial plasma dilution (aPD), 1,645 noninvasive "capillary" plasma dilution (cPD) and 236 estimates of EQ_Hct from 236 perioperative mVLT sessions. The cPD was estimated using noninvasive hemoglobin (SpHb, Masimo Radical 7, Irvine, CA) measurement. Fixed number of crystalloid boluses was used in 36 and 48 elective total knee arthroplasty (TKA) patients, and individualized number of boluses in 34 total hip arthroplasty (THA) patients for whom the number of boluses depended on the advices by our prototype automated clinical decision support system (ACDSS).

Results: The primary hypothesis was confirmed-aPD decreased as EQ_Hct decreased when EQ_Hct <40%, and a very weak positive correlation was found between EQ_Hct and absolute aPD (Spearman's correlation coefficient 0.1025, p < 0.001). It was also confirmed when non-invasive data sets were used. A very weak negative correlation between HctEQ values and absolute cPD values (Spearman's correlation coefficient 0.0640, p = 0.0149).

Conclusion: This study points to the feasibility of Photoplethysmography (PPG) based estimates of hemoglobin concentration for continuous noninvasive monitoring of fluid accumulation and detecting imminent edema using the Homeostatic Blood States (HBS) theory and transcapillary reflux model. The ACDSS-guided fluid loading has a potential to minimise unnecessary fluid accumulation. Further research is needed to explore and improve these techniques.

Introduction: As paradigmatically shown by SARS-CoV-2 vaccines, nucleic acids-based vaccines represent powerful tools to rapidly tackle fast emerging pathogens limiting their spread in human populations and/or reducing the health impact in affected patients. Compared with RNA vaccines, DNA vaccines offer higher stability and amenability to fast development due to tailor-made design of several candidates at a time for (pre)clinical settings. However, their scarce immunogenicity represents an important drawback, requiring technological strategies to enhance cellular uptake, protein expression and increase the ability to induce an immune response.

Methods: We investigated the effects of combining a plant secretory signal sequence of the PolyGalacturonase-Inhibiting Protein (PGIP) from Phaseolus vulgaris with electro-gene transfer (EGT), a technology that increases DNA delivery, on the immune response induced by different SARS-CoV2 experimental DNA vaccines based on domains and peptides of the spike (S), membrane (M) and nucleocapsid (N) proteins.

Results and discussion: All the DNA constructs resulted in protein expression in vitro and in the induction of both antibody and CD4 and CD8T cell responses in mice. EGT significantly increased DNA constructs immunogenicity, especially for the induction of antibody response, confirming its potential in DNA vaccination. Remarkably, constructs including the plant secretory signal sequence resulted to be highly expressed and triggered higher antibody and CD4T cell responses, highlighting that the combination of this sequence and EGT can be used to boost the immunogenicity of DNA-vaccine coded proteins, ultimately helping in their design.

Background: Sustained Acoustic Medicine (SAM) is a non-invasive long-term wearable device that delivers localized long duration high-frequency continuous ultrasound. SAM's biomechanical and diathermic stimuli enhance local circulation and oxygenation, accelerate tissue healing, and alleviate pain. The sonophoresis effects of SAM further improve transdermal drug delivery. Diclofenac is a topical Nonsteroidal anti-inflammatory drug for treating localized musculoskeletal (MSK) pain. Its efficacy is significantly dependent on skin porosity. This study aims to determine the diathermic effects of SAM and diclofenac on localized blood circulation.

Methods: Sixty-four healthy participants were randomly assigned to four groups (Active SAM group: n = 32, Placebo SAM group: n = 32): (A) Coupling gel + placebo SAM), (B) Coupling gel + active SAM, (C) 2.5% Diclofenac gel + placebo SAM, and (D) 2.5% Diclofenac gel + active SAM. Both forearms were treated with a placebo and active SAM devices for 1 h. The blood flux (perfusion units, PU) and temperature (degrees centigrade) change were recorded at 10 min intervals for 60 min using high-laser-power Doppler flowmetry. Blood circulation and temperature were recorded and reported (Clinical trial Identifier: NCT06510062).

Results: SAM increased blood flow significantly over 60 min by 19.2 PU (p < 0.0001) with coupling patch and 18.6 PU with 2.5% diclofenac patch (p < 0.0001) vs. placebo. Surface level tissue temperature increased by Δ2.4°C (p < 0.0001) with gel coupling patch and Δ2.2°C (p < 0.0001) with 2.5% diclofenac patch vs. placebo ultrasound treatment (p < 0.0001). There was no significant difference between standard coupling ultrasound gel and 2.5% diclofenac gel in blood flow and temperature. SAM provided a significant temperature increase at 20 min and a circulation increase at 10 min, which remained for the duration of the 60 min. All participants completed the study with no adverse events.

Conclusion: SAM treatment significantly increases local blood circulation after 10 min, increases temperature after 20 min, and sustains the effects of SAM's stimulation. The 2.5% diclofenac gel does not affect SAM's biological effects to increase local circulation. The study concludes that the application of diclofenac does not affect the diathermic properties of SAM exposure while enhancing the efficacy of diclofenac delivery through sonophoresis.

Clinical trial registration: identifier NCT06510062.