Hydrogel-based therapeutic strategies for spinal cord injury repair: Recent advances and future prospects.

Spinal cord injury (SCI) is a debilitating condition that can result in significant functional impairment and loss of quality of life. There is a growing interest in developing new therapies for SCI, and hydrogel-based multimodal therapeutic strategies have emerged as a promising approach. They offer several advantages for SCI repair, including biocompatibility, tunable mechanical properties, low immunogenicity, and the ability to deliver therapeutic agents. This article provides an overview of the recent advances in hydrogel-based therapy strategies for SCI repair, particularly within the past three years. We summarize the SCI hydrogels with varied characteristics such as phase-change hydrogels, self-healing hydrogel, oriented fibers hydrogel, and self-assembled microspheres hydrogel, as well as different functional hydrogels such as conductive hydrogels, stimuli-responsive hydrogels, adhesive hydrogel, antioxidant hydrogel, sustained-release hydrogel, etc. The composition, preparation, and therapeutic effect of these hydrogels are briefly discussed and comprehensively evaluated. In the end, the future development of hydrogels in SCI repair is prospected to inspire more researchers to invest in this promising field.

Improved brachial skin hydration and appearance with hyperdiluted calcium hydroxylapatite.

INTRODUCTION: The search for minimally invasive treatments for areas not covered by clothing, such as the arms, has increased, particularly to combat flaccidity resulting from factors such as aging and weight loss. This study evaluated the efficacy of calcium hydroxyapatite (CaHA), an injectable biostimulator, in improving flaccidity and hydration of the skin of the arms. MATERIALS AND METHODS: Six women between 40 and 50 years old with visible signs of brachial flaccidity were selected. Calcium hydroxyapatite was injected into the arms in a 1:4 dilution (1.5 mL per side), with subjective evaluation based on the GAIS score and objective hydration analysis using corneometry. RESULTS: After a single application of CaHA, there was a significant increase in skin hydration (12.2%), objectively assessed by corneometry. Patient and physician satisfaction was high, evidenced by visible improvements in photographs and by the GAIS score. No significant adverse events were reported, demonstrating the safety of the procedure. DISCUSSION: Our clinical observations confirm the ability of CaHA to visibly improve arm flaccidity. In addition, hydration measures support previous histological studies demonstrating increases in dermal proteoglycans. Compared to other studies, the increase in skin hydration with CaHA was similar to those obtained with hyaluronic acid, suggesting comparable results with a more comfortable and less invasive technique. CONCLUSION: This study demonstrates the efficacy of CaHA in improving hydration of brachial skin after a single treatment. Despite the limitations of the sample size, the research contributes to the medical literature, highlighting the utility of the 3 mL CaHA presentation for brachial treatment with objective results in skin hydration.

Recent advances in in vitro models simulating the female genital tract toward more effective intravaginal therapeutic delivery.

INTRODUCTION: Intravaginal drug delivery has emerged as a promising avenue for treating a spectrum of systemic and local female genital tract (FGT) conditions, using biomaterials as carriers or scaffolds for targeted and efficient administration. Much effort has been made to understand the natural barriers of this route and improve the delivery system to achieve an efficient therapeutic response. AREAS COVERED: In this review, we conducted a comprehensive literature search using multiple databases (PubMed Scopus Web of Science Google Scholar), to discuss the potential of intravaginal therapeutic delivery, as well as the obstacles unique to this route. The in vitro cell models of the FGT and how they can be applied to probing intravaginal drug delivery are then analyzed. We further explore the limitations of the existing models and the possibilities to make them more promising for delivery studies or biomaterial validation. Complementary information is provided by in vitro acellular techniques that may shed light on mucus-drug interaction. EXPERT OPINION: Advances in 3D models and cell cultures have enhanced our understanding of the FGT, but they still fail to replicate all variables. Future research should aim to use complementary methods, ensure stability, and develop consistent protocols to improve therapy evaluation and create better predictive in vitro models for women's health.

Affinity-based drug delivery systems for the central nervous system: exploiting molecular interactions for local, precise targeting.

Objective: The effective treatment of central nervous system (CNS) disorders remains a significant challenge, primarily due to its molecular and structural complexity. Clinical translation of promising therapeutic agents is limited by the lack of optimal drug delivery systems capable of targeted, localized release of drugs to the brain and spinal cord.Approach: This review provides an overview of the potential of affinity-based drug delivery systems, which leverage molecular interactions to enhance the delivery and efficacy of therapeutic agents within the CNS.Main results: Various approaches, including hydrogels, micro- and nanoparticles, and functionalized biomaterials, are examined for their ability to provide local, sustained release of proteins, growth factors and other drugs.Significance: Furthermore, we present a detailed analysis of design considerations for developing effective affinity-based systems, incorporating insights from both existing literature and our group's research. These considerations include the biochemical modification of delivery vehicles and the optimization of physical and chemical properties to improve therapeutic outcomes.

Clinical and Histological Effects of Calcium Hydroxyapatite Filler in the Orofacial Region: A Study in Rats.

BACKGROUND: Calcium hydroxyapatite (CaHA) dermal filler has been increasingly used in facial aesthetic procedures. OBJECTIVE: To investigate clinical and histological changes associated with calcium hydroxyapatite (CaHA) dermal filler in the orofacial region. MATERIALS AND METHODS: Forty-eight female Wistar rats were divided into CaHA and control groups. The material was applied in the ventral tongue and the submandibular region; the animals were euthanized after 7, 30, and 90 days. RESULTS: After 7 days, yellowish nodules with a firm consistency were observed on the tongue. In 2 animals, the material migrated to the base of the tongue. Histopathological examination revealed CaHA spheres surrounded by an infiltrate, predominantly composed of macrophages. In the CaHA group, the percentage of collagen in the tongue and dermis was higher compared with the control group ( p < .05) at both 30 and 90 days. The thickness of the epidermis/dermis was also higher in the CaHA group ( p < .05). In 5 submandibular glands containing material, areas of edema and hyperemia were observed, along with infiltrates of neutrophils, lymphocytes, and plasma cells. Changes in the morphology of ducts and acini in adjacent regions were evident. CONCLUSION: CaHA exhibits satisfactory properties for filling and collagen biostimulation in the tested regions. Further studies are required to explore the potential for migration and the glandular alterations.

The Extended Utilization of Bulking Agents in Pediatric Urology.

PURPOSE OF REVIEW: Traditional surgical management for urinary incontinence and vesicoureteral reflux often requires complex reconstructive surgery and extended hospitalizations. Since the introduction of endoscopic bulking agents in 1973, there has been increasing interest in the use of endoscopic injection (EI) and bulking for the treatment of a variety of pediatric urologic disorders. The purpose of this review is to summarize the most recent literature addressing the use of bulking agents in pediatric urology. RECENT FINDINGS: The most recent literature has focused primarily on the use of EI of bulking agents at the bladder neck for the treatment of urinary incontinence. Other uses of EI of bulking agents has focused on the treatment of vesicoureteral reflux (VUR) in patients with anatomic abnormalities or treatment of incontinence catheterizable channels. The development of advanced techniques for endoscopic injection along with safe, stable bulking agents has allowed for the treatment of a variety of urologic conditions. This minimally invasive procedure offers an additional tool for the pediatric urologist's armamentarium in the treatment of urinary incontinence and VUR.

A bioactive and biodegradable vitamin C stearate-based injectable hydrogel alleviates experimental inflammatory arthritis.

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory joint disorder affecting nearly 1% of the global population. In RA, synovial joints are infiltrated by inflammatory mediators and enzymes, leading to articular cartilage deterioration, joint damage, and bone erosion. Herein, the 9-aminoacridine-6-O-stearoyl-L-ascorbic acid hydrogel (9AA-SAA hydrogel) was formulated by the heat-cool method and further characterized for surface charge, surface morphology, rheology, and cytocompatibility. Furthermore, we evaluated the therapeutic efficacy of the 9AA-SAA hydrogel, an enzyme-responsive drug delivery system with on-and-off switching capabilities based on disease severity against collagen-induced experimental arthritis in Wistar rats. The anti-inflammatory action of the US FDA-approved drug 9-aminoacridine (9AA) was revealed which acted through nuclear receptor subfamily 4 group A member 1 (NR4A1), an anti-inflammatory orphan nuclear receptor that inhibits nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB). Furthermore, we have explored the role of ascorbic acid, an active moiety of 6-O-stearoyl-L-ascorbic acid (SAA), in promoting the production of collagen production through ten-eleven translocation-2 (TET2) upregulation. Targeting through NR4A1 and TET2 could be the probable mechanism for the treatment of experimental arthritis. The combination of 9AA and ascorbic acid demonstrated enhanced therapeutic efficacy in the 9AA-SAA hydrogel, significantly reducing the severity of experimental arthritis. This approach, in contrast to existing treatments with limited effectiveness, presents a promising and more effective strategy for RA treatment by mitigating inflammation in experimental arthritis.

Injectable conductive hydrogel remodeling microenvironment and mimicking neuroelectric signal transmission after spinal cord injury.

Severe spinal cord injury (SCI) leads to dysregulated neuroinflammation and cell apoptosis, resulting in axonal die-back and the loss of neuroelectric signal transmission. While biocompatible hydrogels are commonly used in SCI repair, they lack the capacity to support neuroelectric transmission. To overcome this limitation, we developed an injectable silk fibroin/ionic liquid (SFMA@IL) conductive hydrogel to assist neuroelectric signal transmission after SCI in this study. The hydrogel can form rapidly in situ under ultraviolet (UV) light. The mechanical supporting and neuro-regenerating properties are provided by silk fibroin (SF), while the conductive capability is provided by the designed ionic liquid (IL). SFMA@IL showed attractive features for SCI repair, such as anti-swelling, conductivity, and injectability. In vivo, SFMA@IL hydrogel used in rats with complete transection injuries was found to remodel the microenvironment, reduce inflammation, and facilitate neuro-fiber outgrowth. The hydrogel also led to a notable decrease in cell apoptosis and the achievement of scar-free wound healing, which saved 45.6 ± 10.8 % of spinal cord tissue in SFMA@IL grafting. Electrophysiological studies in rats with complete transection SCI confirmed SFMA@IL's ability to support sensory neuroelectric transmission, providing strong evidence for its signal transmission function. These findings provide new insights for the development of effective SCI treatments.

Insights of biopolymeric blended formulations for diabetic wound healing.

Diabetic wounds (DWs) pose a significant health burden worldwide, with their management presenting numerous challenges. Biopolymeric formulations have recently gained attention as promising therapeutic approaches for diabetic wound healing. These formulations, composed of biocompatible and biodegradable polymers, offer unique properties such as controlled drug release, enhanced wound closure, and reduced scarring. In this review, we aim to provide a comprehensive overview of the current state of research and future prospects regarding the application of biopolymeric formulations for diabetic wound healing. The review begins by highlighting the underlying pathophysiology of DWs, including impaired angiogenesis, chronic inflammation, and compromised extracellular matrix (ECM) formation. It further explores the key characteristics of biopolymeric materials, such as their biocompatibility, biodegradability, and tunable physicochemical properties, which make them suitable for diabetic wound healing applications. The discussion further delves into the types of biopolymeric formulations utilized in the treatment of DWs. These include hydrogels, nanoparticles (NP), scaffolds, films, and dressings. Furthermore, the review addresses the challenges associated with biopolymeric formulations for diabetic wound healing. In conclusion, biopolymeric formulations present a promising avenue for diabetic wound healing. Their unique properties and versatility allow for tailored approaches to address the specific challenges associated with DWs. However, further research and developments are required to optimize their therapeutic efficacy, stability, manufacturing processes, and regulatory considerations. With continued advancements in biopolymeric formulations, the future holds great promise for improving the management and outcomes of DWs.

Advancing immunotherapy using biomaterials to control tissue, cellular, and molecular level immune signaling in skin.

Immunotherapies have been transformative in many areas, including cancer treatments, allergies, and autoimmune diseases. However, significant challenges persist in extending the reach of these technologies to new indications and patients. Some of the major hurdles include narrow applicability to patient groups, transient efficacy, high cost burdens, poor immunogenicity, and side effects or off-target toxicity that results from lack of disease-specificity and inefficient delivery. Thus, there is a significant need for strategies that control immune responses generated by immunotherapies while targeting infection, cancer, allergy, and autoimmunity. Being the outermost barrier of the body and the first line of host defense, the skin presents a unique immunological interface to achieve these goals. The skin contains a high concentration of specialized immune cells, such as antigen-presenting cells and tissue-resident memory T cells. These cells feature diverse and potent combinations of immune receptors, providing access to cellular and molecular level control to modulate immune responses. Thus, skin provides accessible tissue, cellular, and molecular level controls that can be harnessed to improve immunotherapies. Biomaterial platforms - microneedles, nano- and micro-particles, scaffolds, and other technologies - are uniquely capable of modulating the specialized immunological niche in skin by targeting these distinct biological levels of control. This review highlights recent pre-clinical and clinical advances in biomaterial-based approaches to target and modulate immune signaling in the skin at the tissue, cellular, and molecular levels for immunotherapeutic applications. We begin by discussing skin cytoarchitecture and resident immune cells to establish the biological rationale for skin-targeting immunotherapies. This is followed by a critical presentation of biomaterial-based pre-clinical and clinical studies aimed at controlling the immune response in the skin for immunotherapy and therapeutic vaccine applications in cancer, allergy, and autoimmunity.

Dissolvable microneedles in the skin: Determination the impact of barrier disruption and dry skin on dissolution.

Dissolvable microneedles (DMNs), fabricated from biocompatible materials that dissolve in both water and skin have gained popularity in dermatology. However, limited research exists on their application in compromised skin conditions. This study compares the hyaluronic acid-based DMNs penetration, formation of microchannels, dissolution, and diffusion kinetics in intact, barrier-disrupted (tape stripped), and dry (acetone-treated) porcine ear skin ex vivo. After DMNs application, comprehensive investigations including dermoscopy, stereomicroscope, skin hydration, transepidermal water loss (TEWL), optical coherence tomography (OCT), reflectance confocal laser scanning microscopy (RCLSM), confocal Raman micro-spectroscopy (CRM), two-photon tomography combined with fluorescence lifetime imaging (TPT-FLIM), histology, and scanning electron microscopy (SEM) were conducted. The 400 µm long DMNs successfully penetrated the skin to depths of ≈200 µm for dry skin and ≈200-290 µm for barrier-disrupted skin. Although DMNs fully inserted into all skin conditions, their dissolution rates were high in barrier-disrupted and low in dry skin, as observed through stereomicroscopy and TPT-FLIM. The dissolved polymer exhibited a more significant expansion in barrier-disrupted skin compared to intact skin, with the smallest increase observed in dry skin. Elevated TEWL and reduced skin hydration levels were evident in barrier-disrupted and dry skins compared to intact skin. OCT and RCLSM revealed noticeable skin indentation and pronounced microchannel areas, particularly in barrier-disrupted and dry skin. Additional confirmation of DMN effects on the skin and substance dissolution was obtained through histology, SEM, and CRM techniques. This study highlights the impact of skin condition on DMN effectiveness, emphasizing the importance of considering dissolvability and dissolution rates of needle materials, primarily composed of hyaluronic acid, for optimizing DMN-based drug delivery.

Drug delivery systems for wound healing treatment of upper airway injury.

INTRODUCTION: Endotracheal intubation is a common procedure to maintain an open airway with risks for traumatic injury. Pathological changes resulting from intubation can cause upper airway complications, including vocal fold scarring, laryngotracheal stenosis, and granulomas and present with symptoms such as dysphonia, dysphagia, and dyspnea. Current intubation-related laryngotracheal injury treatment approaches lack standardized guidelines, relying on individual clinician experience, and surgical and medical interventions have limitations and carry risks. AREAS COVERED: The clinical and preclinical therapeutics for wound healing in the upper airway are described. This review discusses the current developments on local drug delivery systems in the upper airway utilizing particle-based delivery systems, including nanoparticles and microparticles, and bulk-based delivery systems, encompassing hydrogels and polymer-based approaches. EXPERT OPINION: Complex laryngotracheal diseases pose challenges for effective treatment, struggling due to the intricate anatomy, limited access, and recurrence. Symptomatic management often requires invasive surgical procedures or medications that are unable to achieve lasting effects. Recent advances in nanotechnology and biocompatible materials provide potential solutions, enabling precise drug delivery, personalization, and extended treatment efficacy. Combining these technologies could lead to groundbreaking treatments for upper airways diseases, significantly improving patients' quality of life. Research and innovation in this field are crucial for further advancements.

A novel biodegradable magnesium skin staple: A safety and functional evaluation.

BACKGROUND: The potential of biodegradable magnesium (Mg) skin staple has recently garnered widespread attention due to their biodegradability and biocompatibility rather than traditional stainless steel staples, the most commonly used in current clinical practice. The aim of this study is to evaluate the safety and mechanical properties of a novel biodegradable Mg skin staple. METHODS: A prototype of Mg skin staple was designed using a novel ZK60 Mg alloy. The mechanical properties of the staple were evaluated using a universal testing machine. The cytotoxicity of the staple was examined in vitro and the efficacy of the staple in wound closure was assessed in New Zealand rabbits for one and three weeks, respectively. RESULTS: The tensile strength of this Mg alloy is 258.4 MPa with 6.9% elongation. The treatment of HaCaT and L929 cells with the staple extract resulted in over 95% cell viability, indicating no cytotoxicity. In vivo, no tissue irritation was observed. No difference was found in wound healing between the Mg skin staple and the stainless steel staple after one and three weeks in the cutting wound on the back of rabbits. Some Mg skin staples spontaneously dislodged from the skin within three weeks, while others were easily removed. CONCLUSION: Our results confirm the safety, biocompatibility, and functionality of the novel Mg skin staple in wound closure. The efficacy of the staple in wound closure was demonstrated to be as effectively as conventional staples, with the added benefit of decreased long-term retention of skin staples in the wounds.

A Structured Approach for Treating Calcium Hydroxylapatite Focal Accumulations.

BACKGROUND: Radiesse, a widely utilized calcium hydroxylapatite (CaHA) dermal filler, has shown effectiveness in soft tissue augmentation and regeneration. As with all dermal fillers, the potential for nodules may arise. Understanding the pathogenesis of these nodules and exploring effective treatment methodologies are crucial for optimizing patient outcomes. OBJECTIVES: A literature search was carried out to identify published literature documenting reversal of CaHA nodules. After identification, a consensus panel developed a structured approach, denoted by levels, for applying such reversal methods. METHODS: This concise review presents an algorithmic approach to addressing CaHA focal accumulations (noninflammatory nodules) based on invasiveness, cost, and potential risks based on published literature. RESULTS: Level 0 involves no intervention, relying on natural degradation for asymptomatic nodules. Level 1 interventions utilize mechanical dispersion techniques, including massage and in situ dispersion, which have demonstrated high success rates, cost effectiveness, and minimal invasiveness. Level 2 introduces alternative modalities such as pharmacological treatments with 5-fluorouracil and corticosteroids, lasers, and experimental approaches. Level 3 represents last-resort options, including calcium-chelating agents, manual removal, and surgical excision. CONCLUSIONS: The article offers a structured approach to managing CaHA focal accumulations.

Dilutional rheology of Radiesse: Implications for regeneration and vascular safety.

BACKGROUND: Calcium hydroxylapatite-carboxymethylcellulose (CaHA-CMC) injectables have emerged as dual-purpose fillers with bioregenerative and direct filling capabilities. AIMS: This study investigates the rheological properties of CaHA-CMC and its CMC carrier gel at various dilutions. METHODS: The storage modulus (G'), loss modulus (G″), complex viscosity (η*), loss factor (tan δ), cohesivity, and extrusion force were evaluated for a range of CaHA-CMC aqueous dilutions with an oscillatory rheometer, drop weight testing, and force analysis, respectively. RESULTS: Results revealed a significant decrease in G', η*, and increase in tan(δ) with increasing dilution, indicating a decline in the product's direct filling capabilities. Cohesivity decreased dramatically with dilution, potentially enhancing tissue biointegration and the product's biostimulatory effects. The CMC gel carrier displayed inelastic and non-resilient properties, with rheological changes differing from CaHA-CMC. Dilutional rheology was also correlated with previously published dilution-dependent biostimulatory data where hyperdiluted CaHA-CMC (>1:2) demonstrated a regenerative profile and diluted or hypodiluted mixtures retained meaningful filling properties and increased regeneration. CONCLUSIONS: These findings offer a continuum for tailoring the product's rheological profile to match specific tissue requirements. Customizable rheology allows CaHA-CMC to be tuned for either filling and contouring or optimal regenerative effects. Importantly, safety implications related to vascular occlusion suggest that dilutional rheomodulation decreases the risk of vascular events. In conclusion, this study highlights the significant impact of aqueous dilution on the rheological properties of CaHA-CMC and its carrier gel. The findings support the clinical application of tailored dilutions to achieve desired outcomes, providing versatility and safety for aesthetic applications.

Mechanical and biological properties of poly-ε-caprolactone membrane for pleurodesis: A preclinical study in pigs.

BACKGROUND/PURPOSE: Biomaterial implants are emerging as a treatment choice for pleurodesis; however, the optimal biomaterial and form for managing spontaneous pneumothorax, particularly post-video-assisted thoracic surgery, remain under investigation. This study evaluated the mechanical and biological properties of the poly-ε-caprolactone (PCL) membrane as a sclerosing agent for pleurodesis in Landrace pigs. METHODS: Twenty-four Landrace pigs were split into two groups for mechanical abrasion and PCL membrane pleurodesis, with the latter group's PCL meshes inserted using video-assisted thoracic surgery. The mechanical and biological properties of the PCL membrane were assessed in pigs at three, six, and 12 months after the procedure. This assessment involved a range of techniques, such as the T-Peel test, macroscopic evaluation with a scoring scale, microscopic examination, and biomechanical and molecular weight analysis. RESULTS: The PCL membrane group outperformed the traditional abrasion group, with stronger adhesions seen over longer implantation durations. This group also showed superior and more consistent results in both macroscopic and microscopic evaluations compared to the control group. The membrane-based method was easier and faster to perform than the control group's method, and importantly, no mortality occurred following membrane implantation. CONCLUSION: This study is the pioneering effort to present long-term findings regarding the mechanical and biological properties of the PCL membrane in an in vivo animal model. The membrane demonstrated better adhesion ability than that of traditional abrasion and showed reassuring biocompatibility in both the pig model, suggesting its potential as treatment for patients with primary spontaneous pneumothorax. Further clinical studies are needed to support these observations.

Injectable tissue prosthesis for instantaneous closed-loop rehabilitation.

To construct tissue-like prosthetic materials, soft electroactive hydrogels are the best candidate owing to their physiological mechanical modulus, low electrical resistance and bidirectional stimulating and recording capability of electrophysiological signals from biological tissues1,2. Nevertheless, until now, bioelectronic devices for such prostheses have been patch type, which cannot be applied onto rough, narrow or deep tissue surfaces3-5. Here we present an injectable tissue prosthesis with instantaneous bidirectional electrical conduction in the neuromuscular system. The soft and injectable prosthesis is composed of a biocompatible hydrogel with unique phenylborate-mediated multiple crosslinking, such as irreversible yet freely rearrangeable biphenyl bonds and reversible coordinate bonds with conductive gold nanoparticles formed in situ by cross-coupling. Closed-loop robot-assisted rehabilitation by injecting this prosthetic material is successfully demonstrated in the early stage of severe muscle injury in rats, and accelerated tissue repair is achieved in the later stage.

Agentes de abultamiento en incontinencia de orina de esfuerzo femenina: una alternativa a las mallas suburetrales / Bulking agents in female stress urinary incontinence: an alternative to suburethral mesh

OBJETIVO: Presentar una serie de casos de agentes de abultamiento (AA) de nuestro centro. MATERIAL Y MÉTODOS: Estudio retrospectivo. Se evaluaron todos los casos operados con AA entre 2017 y 2022. La inyección de AA se realizó en quirófano, bajo sedación con anestesia local periuretral o raquídea. La inyección se realizó con uretroscopia, 0,5 cc en 4 puntos periuretrales (horas 2, 5, 7 y 10). Se analizaron datos demográficos, quirúrgicos y de seguimiento. RESULTADOS: 15 casos. 13/15 presentaron incontinencia urinaria mixta. Solo dos casos tenían incontinencia de orina de esfuerzo pura. El procedimiento fue ambulatorio. La mediana del tiempo operatorio fue 15 minutos (15-20). La mediana de seguimiento fue 5 meses (1-9). El índice de severidad preoperatorio promedio fue 10,6 y en el seguimiento fue 2,79. La Escala de Mejoría Global mostró mejoría en 12/15, y 12/15 estaban satisfechas con la cirugía con mejoría en la calidad de vida. CONCLUSIÓN: Los AA son una opción quirúrgica efectiva, con una tasa de éxito del 80% en otros reportes, siendo similar con nuestra casuística. Ofrecer esta opción es posible a la hora de hablar de terapias alternativas.

OBJECTIVE: To present a case series of bulking agents (BA) from our center. MATERIAL AND METHODS: Retrospective study. All cases operated with BA between 2017 and 2022 were evaluated. A BA injection was performed in the operating room, under periurethral local anesthesia sedation or spinal anesthesia. The injection was performed with urethroscopy, 0.5 cc in 4 periurethral points (hours 2, 5, 7 and 10). Demographic, surgical, and follow-up data were analyzed. RESULTS: 15 cases were reported. 13/15 patients presented with mixed urinary incontinence. Only 2 cases had pure stress urinary incontinence. The procedure was ambulatory. Median operative time was 15 minutes (15-20). Median follow-up was 5 months (1-9). The average preoperative Sandvik Severity Index was 10.6 and in follow-up was 2.79. The PGI showed improvement in 12/15, and 12/15 were satisfied with the surgery with quality-of-life improvement. CONCLUSION: BA are an effective surgical option, with a success rate of 80%, according to other reports, being similar with our casuistry. Offer this option is possible at the moment of discussing alternative therapies.

Introducing aesthetic regenerative scaffolds: An immunological perspective.

BACKGROUND: Skin aging arises from immunological responses to tissue deterioration and damage. Tissue repair processes encompass the regeneration of original tissue and 'scarless' wound healing seen in foetuses, and the extreme fibrotic responses and scarring seen in adults. Anti-aging aesthetic medicine uses interventions like biomaterial-based fillers to influence these immunological responses and renew aged tissue structure and function. At filler injection sites, an inflammatory response occurs that causes a spectrum of outcomes, ranging from tissue regeneration to fibrosis and filler encapsulation. Importantly, the resulting inflammatory pathway can be predetermined by the biomaterial injected. AIMS: By understanding this immunological process, we can develop Aesthetic Regenerative Scaffolds (ARS) - aesthetic injectable biomaterials - to direct inflammatory wound healing away from chronic, fibrotic responses, and towards physiological tissue regeneration. MATERIALS AND METHODS: We identified and reviewed literature on the immunological and cellular responses to injected dermal fillers, whereby the wound healing response to the injection was moderated under the influence of an injected biomaterial. RESULTS: We described the mechanisms of dermal wound healing and the use of ARS to direct healing towards tissue regeneration instead of scarring. We also summarised studies on extracellular matrix remodeling by calcium hydroxylapatite. We found that Calcium hydroxylapatite fillers produce collagen as they gradually degrade and their spherical structures serve as a scaffold for tissue regeneration. Furthermore, CaHA improved fibroblast contractility, collagen type III and elastin production, proliferation and angiogenesis with less inflammation than hyaluronic acid fillers. DISCUSSION: Regneration pathways can be influenced at specific points between a facial filler biomaterial and the wound healingmechanisms at its site of implantaion. CONCLUSION: Physicians can select scaffolds that direct the immune response away from a fibrotic chronic inflammatory pathway and towards regeneration to enable true repair of the aging skin.