High-Performance Flexible Sensor with Sensitive Strain/Magnetic Dual-Mode Sensing Characteristics Based on Sodium Alginate and Carboxymethyl Cellulose.

Flexible sensors can measure various stimuli owing to their exceptional flexibility, stretchability, and electrical properties. However, the integration of multiple stimuli into a single sensor for measurement is challenging. To address this issue, the sensor developed in this study utilizes the natural biopolymers sodium alginate and carboxymethyl cellulose to construct a dual interpenetrating network, This results in a flexible porous sponge that exhibits a dual-modal response to strain and magnetic stimulation. The dual-mode flexible sensor achieved a maximum tensile strength of 429 kPa and elongation at break of 24.7%. It also exhibited rapid response times and reliable stability under both strain and magnetic stimuli. The porous foam sensor is intended for use as a wearable electronic device for monitoring joint movements of the body. It provides a swift and stable sensing response to mechanical stimuli arising from joint activities, such as stretching, compression, and bending. Furthermore, the sensor generates opposing response signals to strain and magnetic stimulation, enabling real-time decoupling of different stimuli. This study employed a simple and environmentally friendly manufacturing method for the dual-modal flexible sensor. Because of its remarkable performance, it has significant potential for application in smart wearable electronics and artificial electroskins.

Chemical and biological prospection of marine sponges belonging to the class Demospongiae: a review.

Marine sponges belonging to the class Demospongiae have been shown to be promising sources of bioactive compounds, investigated from the perspective of potential medical applications. This review aimed to collect studies on biological activities of clinical importance and the chemical composition of sponge species from that class, highlighting the structure/activity relationship. To carry out this work, collections were carried out in the Science Direct, Pubmed, Scielo and Google Scholar databases, using the following descriptors: antimicrobial marine sponges, antioxidant marine sponges and marine sponges biological activity. The inclusion criteria were considered: (1) publications from the year 2022 onwards; (2) written in English or Portuguesen and (3) with information on biological assays of extracts, fractions or isolated compounds. The following were excluded: (1) duplicate works; (2) works whose content was not within the scope of the study and (3) studies that did not evaluate biological activities. Results demonstrate that 274 compounds were isolated from different metabolic classes, being evaluated in several biological assays. From the analysis of the data, it is concluded that the compounds studied demonstrate promise for the development of medicines for the control of microorganisms and the treatment of tumors, acting through different mechanisms of action.

Chemical Profile, Antioxidant and Antimicrobial Activity of Marine Sponge Species Combined with Multivariate Statistical Analyses: Desmapsamma anchorata, Dysidea etheria and Echinodictyum dendroides.

Marine sponges are sources of bioactive compounds, sparking pharmacological interest. This study aimed to evaluate the chemical profile, antioxidant, and antibacterial activities of the species Desmapsamma anchorata, Dysidea etheria, and Echinodictyum dendroides. The chemical profile was characterized by the identification and quantification of polyphenols. Antioxidant activity was assessed using different methods. Antibacterial and modulatory activities were evaluated through microdilution against pathogenic strains. The polyphenols were found in low abundance in the extracts. In the antioxidant assays, the EACDa and EMDa extracts exhibited better inhibitory results. In the antibacterial evaluation, extracts presented MIC ≥ 1024 µg mL-1. The modulation of the extracts in combination with antibiotics showed significant effects against the multiresistant bacterium Pseudomonas aeruginosa. This study contributes to the deepening of chemical and biological knowledge of sponge species, indicating that their extracts can act as good modulators of bacterial resistance to aminoglycoside antibiotics, warranting further investigation into their mechanisms of action.

Efficacy and safety of intraoperative injection of mitomycin C during trabeculectomy: a systematic review and meta-analysis.

PURPOSE: Trabeculectomy, a primary surgical treatment for glaucoma, often employs mitomycin C (MMC) to reduce scar formation and improve surgical outcomes. However, the optimal application method of MMC, whether by injection or sponge, remains a subject of debate. This meta-analysis aims to compare injectable and sponge-based MMC application in terms of efficacy and safety, focusing on various clinical outcomes in glaucoma patients. METHODS: A comprehensive literature search of Scopus, MEDLINE, EMBASE, Ovid, Chinese biomedical literature database, China National Knowledge Infrastructure, and Cochrane Library was done for eligible studies that report data of glaucoma patients who were administered MMC by injection or sponge application during trabeculectomy. Outcomes of interest included intraocular pressure (IOP) reduction, bleb appearance grading (height, extent, vascularity), use of anti-glaucoma medications, and rates of complete success, qualified success, and failure. Data were reported as weighted mean differences (WMD) or odds ratios (OR) with confidence intervals (CI). The random-effects inverse-variance model with DerSimonian-Laird estimate of tau2 was employed, with continuity correction applied where necessary. RESULTS: A total of 15 studies with 1276 participants were included. The meta-analysis revealed no significant difference in IOP reduction between patients treated by MMC injection and sponge application (WMD = - 0.434). Significant differences were observed in bleb appearance grading scores for height (WMD = - 0.170) and extent (WMD = 0.174), with substantial heterogeneity. The use of anti-glaucoma medications was significantly lower in the injection group (WMD = - 0.274). However, there were no significant differences in the rates of complete success, qualified success, and failure. The study demonstrated moderate to high heterogeneity across various outcomes. CONCLUSION: This meta-analysis indicated that while both injection and sponge methods of MMC application during trabeculectomy were equally effective for IOP reduction, they differ in their impact on bleb morphology and postoperative medication requirement. The findings highlight the need for individualized treatment approaches in glaucoma surgery, taking into account the specific needs and characteristics of each patient.

A facile way to fabricate a thrombin immobilized composite sponge with dual hemostatic effects for acute hemorrhage control.

Uncontrolled bleeding and excessive blood loss stand as the leading causes of death in complex surgeries, civilian traumas, and military operations. Sponges have been used for developing efficiency hemostats, but most commonly used hemostatic sponges possess only one single coagulation mechanism or lack inherent blood clotting ability. Herein, we proposed simple yet innovative approaches for creating novel hemostatic composite sponges with dual hemostatic effects. Bacterial cellulose (BC) was first introduced into polyvinyl alcohol (PVA) matrix to develop a BC/PVA (CP) sponge featuring a unique cellulose-embedded porous network structure and desirable properties. Subsequently, thrombin was immobilized on CP through an easy method that combines physical adsorption and covalent binding to fabricate thrombin-carrying CP (TCP) composite sponges. The resulting composites boasted a highly porous structure, outstanding liquid-absorption capacity, low hemolysis rate, and superior biocompatibility. In vitro clotting tests revealed that TCP displayed potent coagulation capabilities, a rapid blood absorption rate, and the ability to stimulate and activate blood components along with the coagulation cascade. In vivo hemostatic assessments further confirmed that TCP offered high hemostatic efficiency and multifaceted hemostatic effects, making it suitable for the management of acute and severe bleeding.

Unraveling the Enigma of Gossypiboma: A Series of 14 Cases Highlighting the Prevalence, Root Causes, and Outcomes in Resource-Limited Settings.

BACKGROUND: Gossypiboma or textiloma is the unintentional retention of textile material in a patient's body, often occurring during abdominal surgery and involving surgical sponges. The body may respond to this foreign body with an exudative inflammatory reaction or an aseptic fibrotic reaction, encapsulating the cotton material and forming a mass. This rare but dramatic event can lead to life-threatening complications, and due to legal and ethical concerns, few publications exist. There were no published papers regarding this issue in our nation (Yemen). This study aims to report the retained surgical sponges' cases and their associated factors in a resource-limited setting to improve prevention. MATERIALS AND METHODS: A retrospective case series study was conducted at hospitals affiliated with Ibb University, Ibb, Yemen, between March 22, 2018, and May 12, 2024. The study included 14 cases of diagnosed and surgically confirmed retained surgical sponges. Data on demographic characteristics, type of operation, and risk factors were gathered and analyzed. RESULT: Among 15,120 surgical procedures, there were 14 cases of retained surgical sponges with a prevalence rate of 0.09%. The mean age was 32.5±17.0 years, with 10 (71.4%) females and 4 (28.6%) males. Gynecological surgery was the most common causal procedure (n=7, 50.0%). The most common clinical presenting features were abdominal pain in 12 (85.7%), followed by infections and a systemic reaction in 9 (64.3%). The median symptom incubation time was 37 days. 11 (78.5%) patients underwent abdominal X-rays, and 13 (92.8%) had abdominal ultrasounds, with 4 (28.6%) X-rays and 5 (35.7%) abdominal ultrasounds being deemed non-diagnostic. An abdominal-pelvic CT scan was done on 11 (78.5%) individuals, with the results being diagnostic in 10 (71.4%) and non-diagnostic in one (7.1%). The leading causes for gossypiboma occurrence were prolonged surgical procedures > one hour and emergency in 7 (50.0%) cases, followed by multiple surgical team involvement and change in nursing staff during procedures in 5 (35.7%) cases. CONCLUSION: A gossypiboma or retained foreign body diagnosis can be achieved through comprehensive patient history, radiologist-surgeon interaction, understanding of risk factors, and familiarity with imaging patterns. Safety procedures should be robust and straightforward, and effective communication among surgical professionals can help minimize medical negligence and protect patients in chaotic situations. Furthermore, the surgeon should adhere to the standard prescribed method and report cases of retained surgical sponges.

Anterioposterior Views Coupled With Lateral Views Are the Best for the Intraoperative Radiographic Detection of Retained Surgical Sponges.

INTRODUCTION: A retained sponge after spine surgery can cause serious medical complications and medicolegal problems. Intraoperative radiographs are commonly used to detect it. This study evaluated intraoperative radiographs under routine clinical conditions that most spine surgeons experience to detect retained sponges. METHODS: In this prospective randomized clinical trial, two patient groups undergoing open posterior lumbar surgery were studied. In one, a sponge was intentionally present; in the other, none was present. Standard intraoperative lateral (LAT) and anteroposterior (AP) radiographs were acquired before closing. Radiographs were analyzed for sensitivity, specificity, inter- and intraobserver reliability for three viewing conditions: one LAT radiograph versus one AP radiograph versus one LAT and one AP X-ray (LAT+AP). RESULTS: A total of 111 patients were included. Accuracy, interobserver reliability, and intraobserver reliability were best for LAT+AP (80%, 96%, and 96%, respectively). Sensitivity was best for LAT+AP (87%) and specificity was best for LAT (95%). Positive predictive value was best for LAT (94%); negative predictive value was best for LAT+AP (88%). The probability of being right is better for female sex (odds ratio 1.6), younger age (odds ratio 1.02), and higher BMI (odds ratio 1.06). CONCLUSIONS: We recommend AP with LAT images rather than either an AP or a LAT image alone.

Genomics of Terpene Biosynthesis in Dictyoceratid Sponges (Porifera) - What Do We (Not) Know?

Sponges are recognized as promising sources for novel bioactive metabolites. Among them are terpenoid metabolites that constitute key biochemical defense mechanisms in several sponge taxa. Despite their significance, the genetic basis for terpenoid biosynthesis in sponges remains poorly understood. Dictyoceratida comprise demosponges well-known for their bioactive terpenoids. In this study, we explored the currently available genomic data for insights into the metabolic pathways of dictyoceratid terpenoids. We first identified prenyltransferase (PT) and terpene cyclase (TC) enzymes essential for the terpenoid biosynthetic processes in the terrestrial realm by analyzing available transcriptomic and genomic data of Dictyoceratida sponges and 10 other sponge species. All Dictyoceratida sponges displayed various PTs involved in either sesqui- or diterpene, steroid and carotenoid production. Additionally, it was possible to identify a potential candidate for a dictyoceratid sesterterpene PT. However, analogs of common terrestrial TCs were absent, suggesting the existence of a distinct or convergently evolved sponge-specific TC. Our study aims to contribute to the foundational understanding of terpene biosynthesis in sponges, unveiling the currently evident genetic components for terpenoid production in species not previously studied. Simultaneously, it aims to identify the known and unknown factors, as a starting point for biochemical and genetic investigations in sponge terpenoid production.

In Vivo Effects of Biosilica and Spongin-Like Collagen Scaffolds on the Healing Process in Osteoporotic Rats.

Due to bioactive properties, introducing spongin-like collagen (SPG) into the biosilica (BS) extracted from marine sponges would present an enhanced biological material for improving osteoporotic fracture healing by increasing bone formation rate. Our aim was to characterize the morphology of the BS/SPG scaffolds by scanning electron microscopy (SEM), the chemical bonds of the material by Fourier transform infrared spectroscopy (FTIR), and evaluating the orthotopic in vivo response of BS/SPG scaffolds in tibial defects of osteoporotic fractures in rats (histology, histomorphometry, and immunohistochemistry) in two experimental periods (15 and 30 days). SEM showed that scaffolds were porous, showing the spicules of BS and fibrous aspect of SPG. FTIR showed characteristic peaks of BS and SPG. For the in vivo studies, after 30 days, BS and BS/SPG showed a higher amount of newly formed bone compared to the first experimental period, observed both in the periphery and in the central region of the bone defect. For histomorphometry, BS/SPG presented higher %BV/TV compared to the other experimental groups. After 15 days, BS presented higher volumes of collagen type I. After 30 days, all groups demonstrated higher volumes of collagen type III compared to volumes at 15 days. After 30 days, BS/SPG presented higher immunostaining of osteoprotegerin compared to the other experimental groups at the same experimental period. The results showed that BS and BS/SPG scaffolds were able to improve bone healing. Future research should focus on the effects of BS/SPG on longer periods in vivo studies.

Silactins and Structural Diversity of Biosilica in Sponges.

Sponges (phylum Porifera) were among the first metazoans on Earth, and represent a unique global source of highly structured and diverse biosilica that has been formed and tested over more than 800 million years of evolution. Poriferans are recognized as a unique archive of siliceous multiscaled skeletal constructs with superficial micro-ornamentation patterned by biopolymers. In the present study, spicules and skeletal frameworks of selected representatives of sponges in such classes as Demospongiae, Homoscleromorpha, and Hexactinellida were desilicified using 10% HF with the aim of isolating axial filaments, which resemble the shape and size of the original structures. These filaments were unambiguously identified in all specimens under study as F-actin, using the highly specific indicators iFluor™ 594-Phalloidin, iFluor™ 488-Phalloidin, and iFluor™ 350-Phalloidin. The identification of this kind of F-actins, termed for the first time as silactins, as specific pattern drivers in skeletal constructs of sponges opens the way to the fundamental understanding of their skeletogenesis. Examples illustrating the biomimetic potential of sophisticated poriferan biosilica patterned by silactins are presented and discussed.

Transcriptomic responses of Mediterranean sponges upon encounter with symbiont microbial consortia.

BACKGROUND: Sponges (phylum Porifera) constantly interact with microbes. They graze on microbes from the water column by filter-feeding and they harbor symbiotic partners within their bodies. In experimental setups, sponges take up symbionts at lower rates compared with seawater microbes. This suggests that sponges have the capacity to differentiate between microbes and preferentially graze in non-symbiotic microbes, although the underlying mechanisms of discrimination are still poorly understood. Genomic studies showed that, compared to other animal groups, sponges present an extended repertoire of immune receptors, in particular NLRs, SRCRs, and GPCRs, and a handful of experiments showed that sponges regulate the expression of these receptors upon encounter with microbial elicitors. We hypothesize that sponges may rely on differential expression of their diverse repertoire of poriferan immune receptors to sense different microbial consortia while filter-feeding. To test this, we characterized the transcriptomic response of two sponge species, Aplysina aerophoba and Dysidea avara, upon incubation with microbial consortia extracted from A. aerophoba in comparison with incubation with seawater microbes. The sponges were sampled after 1 h, 3 h, and 5 h for RNA-Seq differential gene expression analysis. RESULTS: D. avara incubated with A. aerophoba-symbionts regulated the expression of genes related to immunity, ubiquitination, and signaling. Within the set of differentially-expressed immune genes we identified different families of Nucleotide Oligomerization Domain (NOD)-Like Receptors (NLRs). These results represent the first experimental evidence that different types of NLRs are involved in microbial discrimination in a sponge. In contrast, the transcriptomic response of A. aerophoba to its own symbionts involved comparatively fewer genes and lacked genes encoding for immune receptors. CONCLUSION: Our work suggests that: (i) the transcriptomic response of sponges upon microbial exposure may imply "fine-tuning" of baseline gene expression as a result of their interaction with microbes, (ii) the differential response of sponges to microbial encounters varied between the species, probably due to species-specific characteristics or related to host's traits, and (iii) immune receptors belonging to different families of NLR-like genes played a role in the differential response to microbes, whether symbionts or food bacteria. The regulation of these receptors in sponges provides further evidence of the potential role of NLRs in invertebrate host-microbe interactions. The study of sponge responses to microbes exemplifies how investigating different animal groups broadens our knowledge of the evolution of immune specificity and symbiosis.

Pharmacokinetic study of local and systemic gentamicin concentrations after subcutaneous implantation of a gentamicin-impregnated collagen sponge in dogs.

This study evaluated the pharmacokinetics of commercial gentamicin-impregnated collagen sponges (GICS) applied subcutaneously in dogs. In six healthy beagles, an 11 ×6 cm subcutaneous pocket was created, a folded 10×10 cm GICS was inserted, and saline was injected to mimic a seroma. Wound fluid samples were aspirated, and the gentamicin concentration was determined. Simultaneously, blood samples were collected to evaluate the corresponding systemic gentamicin concentration. All samples were collected before and 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 18, 24, 36, 48, 72, 96, 120, and 168 hours after GICS placement. The local Cmax of gentamicin was reached after 0.5 hours (range, 0.5-1.0 hours) post-implantation in 5/6 dogs at a median concentration of 2053.3 µg/mL (range, 918.0-2791.9 µg/mL). Whitin 24 hours, the local concentration dropped below the MIC for Staphylococcus sp. (4 µg/mL) in 5/6 dogs. Plasma Cmax was achieved at a median of 1.2 hours post-implantation (range, 1.0-2.0 hours) and reached a median concentration of 10.3 µg/mL (range, 8.8-18.03 µg/mL). After 6 hours, the gentamicin concentration in the plasma was below 4 µg/mL in all dogs. The GICS provided a high local concentration of gentamicin in a short time with a local Cmax:MIC ratio of 513:1, largely sufficient to eliminate susceptible bacteria, including methicillin-resistant Staphylococcus pseudintermedius (MRSP) and Pseudomonas sp., in a clinical setting. The repeated administration of saline in the present study seemed to have induced a quicker gentamicin release from the GICS than described in previous studies that typically dealt with "drier" wounds.

Appraisal terpenoids rich Boswellia carterri ethyl acetate extract in binary cyclodextrin oligomer nano complex for improving respiratory distress.

Boswellia carterii (BC) resins plants have a long historical background as a treatment for inflammation, as indicated by information originating from multiple countries. Twenty-seven diterpenoids have been identified in ethyl acetate and total methanol BC, comprising seventeen boscartins of the cembrane-type diterpenoids and ten boscartols of the prenylaromadendrane-type diterpenoids. Moreover, twenty-one known triterpenoids have also been found, encompassing nine tirucallane-type, six ursane-type, four oleanane-type, and two lupane-type. The cembrane-type diterpenoids hold a significant position in pharmaceutical chemistry and related industries due to their captivating biological characteristics and promising pharmacological potentials. Extraction of BC, creation and assessment of nano sponges loaded with either B. carterii plant extract or DEX, are the subjects of our current investigation. With the use of ultrasound-assisted synthesis, nano sponges were produced. The entrapment efficiency (EE%) of medications in nano sponges was examined using spectrophotometry. Nano sponges were characterized using a number of methods. Within nano sponges, the EE% of medicines varied between 98.52 ± 0.07 and 99.64 ± 1.40%. The nano sponges' particle sizes varied from 105.9 ± 15.9 to 166.8 ± 26.3 nm. Drugs released from nano sponges using the Korsmeyer-Peppas concept. In respiratory distressed rats, the effects of BC plant extract, DEX salt and their nano formulations (D1, D5, P1 and P1), were tested. Treatment significantly reduced ICAM-1, LTB4, and ILß 4 levels and improved histopathologic profiles, when compared to the positive control group. Boswellia extract and its nano sponge formulation P1 showed promising therapeutic effects. The effect of P1 may be due to synergism between both the extract and the formulation. This effect was achieved by blocking both ICAM-1 and LTB4 pathways, therefore counteracting the effects of talc powder.

Streamlining large-scale oceanic biomonitoring using passive eDNA samplers integrated into vessel's continuous pump underway seawater systems.

Passive samplers are enabling the scaling of environmental DNA (eDNA) biomonitoring in our oceans, by circumventing the time-consuming process of water filtration. Designing a novel passive sampler that does not require extensive sample handling time and can be connected to ocean-going vessels without impeding normal underway activities has potential to rapidly upscale global biomonitoring efforts onboard the world's oceanic fleet. Here, we demonstrate the utility of an artificial sponge sampler connected to the continuous pump underway seawater system as a means to enable oceanic biomonitoring. We compared the performance of this passive sampling protocol with standard water filtration at six locations during a research voyage from New Zealand to Antarctica in early 2023. Eukaryote metabarcoding of the mitochondrial COI gene revealed no significant difference in phylogenetic α-diversity between sampling methods and both methods delineated a progressive reduction in number of Zero-Radius Operational Taxonomic Units (ZOTUs) with increased latitudes. While both sampling methods revealed comparable trends in geographical community compositions, distinct clusters were identified for passive samplers and water filtration at each location. Additionally, greater variability between replicates was observed for passive samplers, resulting in an increased estimated level of replication needed to recover 90 % of the biodiversity. Furthermore, traditional water filtration failed to detect three phyla observed by passive samplers and extrapolation analysis estimated passive samplers recover a larger number of ZOTUs compared to water filtration for all six locations. Our results demonstrate the potential of this passive eDNA sampler protocol and highlight areas where this emerging technology could be improved, thereby enabling large-scale offshore marine eDNA biomonitoring by leveraging the world's oceanic fleet without interfering with onboard activities.

Methanolic Extract and Brominated Compound from the Brazilian Marine Sponge Aplysina fulva Are Neuroprotective and Modulate Inflammatory Profile of Microglia.

Neurodegenerative diseases involve neuroinflammation and a loss of neurons, leading to disability and death. Hence, the research into new therapies has been focused on the modulation of the inflammatory response mainly by microglia/macrophages. The extracts and metabolites of marine sponges have been presented as anti-inflammatory. This study evaluated the toxicity of an extract and purified compound from the Brazilian marine sponge Aplysina fulva as well as its neuroprotection against inflammatory damage associated with the modulation of microglia response. PC12 neuronal cells and neonatal rat microglia were treated with the methanolic extract of A. fulva (AF-MeOH, 0.1-200 µg/mL) or with its purified dimethyl ketal of 3,5-dibromoverongiaquinol (AF-H1, 0.1-100 µM). Cytotoxicity was determined by MTT tetrazolium, Trypan blue, and propidium iodide; microglia were also treated with the conditioned medium (CM) from PC12 cells in different conditions. The microglia phenotype was determined by the expression of Iba-1 and CD68. AF-MeOH and AF-H1 were not toxic to PC12 or the microglia. Inflammatory damage with Escherichia coli lipopolysaccharide (LPS, 5 µg/mL) was not observed in the PC12 cells treated with AF-MeOH (1-10 µg/mL) or AF-H1 (1-10 µM). Microglia subjected to the CM from PC12 cells treated with LPS and AF-MeOH or AF-H1 showed the control phenotype-like (multipolar, low-CD68), highlighting the anti-neuroinflammatory and neuroprotective effect of components of this marine sponge.

Engineered phalangeal grafts for children with symbrachydactyly: A proof of concept.

Tissue engineering approaches hold great promise in the field of regenerative medicine, especially in the context of pediatric applications, where ideal grafts need to restore the function of the targeted tissue and consider growth. In the present study, we aimed to develop a protocol to engineer autologous phalangeal grafts of relevant size for children suffering from symbrachydactyly. This condition results in hands with short fingers and missing bones. A previously-described, developmentally-inspired strategy based on endochondral ossification (ECO)-the main pathway leading to bone and bone marrow development-and adipose derived-stromal cells (ASCs) as the source of chondroprogenitor was used. First, we demonstrated that pediatric ASCs associated with collagen sponges can generate hypertrophic cartilage tissues (HCTs) in vitro that remodel into bone tissue in vivo via ECO. Second, we developed and optimized an in vitro protocol to generate HCTs in the shape of small phalangeal bones (108-390 mm3) using freshly isolated adult cells from the stromal vascular fraction (SVF) of adipose tissue, associated with two commercially available large collagen scaffolds (Zimmer Plug® and Optimaix 3D®). We showed that after 12 weeks of in vivo implantation in an immunocompromised mouse model such upscaled grafts remodeled into bone organs (including bone marrow tissues) retaining the defined shape and size. Finally, we replicated similar outcome (albeit with a slight reduction in cartilage and bone formation) by using minimally expanded pediatric ASCs (3 × 106 cells per grafts) in the same in vitro and in vivo settings, thereby validating the compatibility of our pediatric phalanx engineering strategy with a clinically relevant scenario. Taken together, these results represent a proof of concept of an autologous approach to generate osteogenic phalangeal grafts of pertinent clinical size, using ASCs in children born with symbrachydactyly, despite a limited amount of tissue available from pediatric patients.

Mild preparation of hyaluronic acid/silk fibroin sponges by modified crosslinking method.

The composites composed of hyaluronic acid (HA) and silk fibroin (SF) exhibit great potential in diverse biomedical applications. However, the utilization of commercial crosslinkers such as 1,4-butanediol diglycidyl ether (BDDE) for crosslinking HA typically necessitates harsh conditions involving strong alkaline, which greatly limits its potential applications. In this study, a mild modified approach was developed to fabricate HA/SF blend sponges crosslinked by BDDE without alkaline conditions. The blend solutions were cryo-concentrated to induce crosslinking reactions. The mechanism of freezing crosslinking was elucidated by investigating the effects of ice crystal growth and HA molecular weight on the degree of crosslinking. The results revealed that HA achieved efficient crosslinking when its molecular weight exceeds 1000 kDa and freezing temperatures ranged from -40 °C to -20 °C. After introducing SF, multiple crosslinks were formed between SF and HA chains, producing water-stable porous sponges. The SEM results demonstrated that the introduction of SF effectively enhanced the interconnectivity between macropores through creating subordinate holes onto the pores wall. Raising the SF content significantly enhanced compression strength, resistance to enzymatic degradation and cell viability of blend sponges. This study provides a novel strategy for designing bioactive HA/SF blend sponges as substitutes for tissue repair and wound dressing.

Mechanochemical Formation of Poly(melamine-formaldehyde) Microplastic Fibers During Abrasion of Cleaning Sponges.

The abrasion of synthetic textile fibers is a significant factor in the generation of environmental microplastic fibers (MPFs). The extent to which polymer sponges designed specifically for surface cleaning have a tendency to release MPFs during normal use remains unknown. Here, the tribological behaviors of melamine cleaning sponges (also known as "magic erasers") with different strut densities against metal surfaces of different roughness were investigated using a reciprocating abrader. The MPFs formed by sponge wear under various conditions were characterized in terms of their morphology, composition, and quantity. They were mainly composed of poly(melamine-formaldehyde) polymer with linear or branched fiber morphologies (10-405 µm in length), which were formed through deformation and fracture of the struts within open cells of the sponges, facilitated by friction-induced polymer decomposition. The rate and capability of MPF production generally increased with increasing roughness of the metal surface and density of the struts, respectively. The sponge wear could release 6.5 million MPFs/g, which could suggest a global overall emission of 4.9 trillion MPFs due to sponge consumption. Our study reveals a hitherto unrecognized source of the environmental MPF contamination and highlights the need to evaluate exposure risks associated with these new forms of MPFs.

Wound Dressing Based on Cassava Silk-Chitosan.

The application prospects of composite sponges with antibacterial and drug-carrying functions in the field of medical tissue engineering are extensive. A solution of cassava silk fibroin (CSF) was prepared with Ca(NO3)2 as a solvent, which was then combined with chitosan (CS) to create a sponge-porous material by freeze-drying. The CSF-CS composite sponge with a mesh structure was successfully fabricated through hydrogen bonding. Scanning electron microscopy (SEM), Fourier transform infrared absorption (FTIR) and X-ray diffraction (XRD) were employed to investigate the appearance and structure of the cassava silk's fibroin materials, specifically examining the impact of different mass percentages of CS on the sponge's structure. The swelling rate and mechanical properties of the CSF-CS sponge were analyzed, along with its antibacterial properties. Furthermore, by incorporating ibuprofen as a model drug into these loaded sponges, their potential efficacy as efficient drug delivery systems was demonstrated. The results indicate that the CSF-CS sponge possesses a three-dimensional porous structure with over 70% porosity and an expansion rate exceeding 400% while also exhibiting good resistance against pressure. Moreover, it exhibits excellent drug-carrying ability and exerts significant bacteriostatic effects on Escherichia coli. Overall, these findings support considering the CSF-CS composite sponge as a viable candidate for use in drug delivery systems or wound dressings.