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Abstract Chronic ulcers significantly affect the quality of life of patients and impose a high cost on the healthcare system. The therapeutic management should be comprehensive, taking into consideration the etiological diagnosis of the wound and the characteristics of the wound bed when deciding on a therapeutic proposal appropriate to the healing phase, correcting factors that delay healing. During the epithelialization phase, repair techniques with grafts are recommended to shorten re-epithelialization time, improve the quality of scar tissue, and achieve adequate pain management. Currently, due to the reported benefits of skin appendages, the technique of follicular unit auto-grafting obtained with a scalp punch is among the chosen strategies for wound repair. This is a minimally invasive, outpatient practice, whose technique has advantages over the donor site, patients recovery and well-being.

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BACKGROUND: Ischemic cardiomyopathy (ICM) accounts for more than 60% of congestive heart failure cases and is associated with high morbidity and mortality rates. Myocardial revascularization in patients with left ventricular dysfunction (LVD) and a left ventricular ejection fraction (LVEF) ≤35% aims to improve survival and quality of life and reduce complications associated with heart failure and coronary artery disease. The majority of randomized clinical trials have consistently excluded those patients, resulting in evidence primarily derived from observational studies. MAIN BODY: We performed a scoping review using the Arksey and O'Malley methodology in five stages: 1) formulating the research question; 2) locating relevant studies; 3) choosing studies; 4) organizing and extracting data; and 5) compiling, summarizing, and presenting the findings. This literature review covers primary studies and systematic reviews focusing on surgical revascularization strategies in adult patients with ischemic left ventricular dysfunction (LVD) and a left ventricular ejection fraction (LVEF) of 35% or lower. Through an extensive search of Medline and the Cochrane Library, a systematic review was conducted to address three questions regarding myocardial revascularization in these patients. These questions outline the current knowledge on this topic, current surgical strategies (off-pump vs. on-pump), and graft options (including hybrid techniques) utilized for revascularization. Three independent reviewers (MAE, DP, and AM) applied the inclusion criteria to all the included studies, obtaining the full texts of the most relevant studies. The reviewers subsequently assessed these articles to make the final decision on their inclusion in the review. Out of the initial 385 references, 156 were chosen for a detailed review. After examining the full articles were examined, 134 were found suitable for scoping review. CONCLUSION: The literature notes the scarcity of surgical revascularization in LVD patients in randomized studies, with observational data supporting coronary revascularization's benefits. ONCABG is recommended for multivessel disease in LVD with LVEF < 35%, while OPCAB is proposed for older, high-risk patients. Strategies like internal thoracic artery skeletonization harvesting and postoperative glycemic control mitigate risks with BITA in uncontrolled diabetes. Total arterial revascularization maximizes long-term survival, and hybrid revascularization offers advantages like shorter hospital stays and reduced costs for significant LAD lesions.

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Rubber tree (Hevea brasiliensis) is reproduced by bud grafting for commercial planting, but significant intraclonal variations exist in bud-grafted clones. DNA methylation changes related to grafting may be partly responsible for intraclonal variations. In the current study, whole-genome DNA methylation profiles of grafted rubber tree plants (GPs) and their donor plants (DPs) were evaluated by whole-genome bisulfite sequencing. Data showed that DNA methylation was downregulated and DNA methylations in CG, CHG, and CHH sequences were reprogrammed in GPs, suggesting that grafting induced the reprogramming of DNA methylation. A total of 5,939 differentially methylated genes (DMGs) were identified by comparing fractional methylation levels between GPs and DPs. Transcriptional analysis revealed that there were 9,798 differentially expressed genes (DEGs) in the DP and GP comparison. A total of 1,698 overlapping genes between DEGs and DMGs were identified. These overlapping genes were markedly enriched in the metabolic pathway and biosynthesis of secondary metabolites by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Global DNA methylation and transcriptional analyses revealed that reprogramming of DNA methylation is correlated with gene expression in grafted rubber trees. The study provides a whole-genome methylome of rubber trees and an insight into the molecular mechanisms underlying the intraclonal variations existing in the commercial planting of grafted rubber trees.

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Introduction Facial trauma can cause damage to the facial nerve, which can have negative effects on function, aesthetics, and quality of life if left untreated. Objective To evaluate the effectiveness of peripheral facial nerve direct end-to-end anastomosis and/or nerve grafting surgery for patients with facial nerve injury after facial trauma. Methods Fifty-nine patients with peripheral facial nerve paralysis after facial injuries underwent facial nerve rehabilitation surgery from November 2017 to December 2021 at Ho Chi Minh City National Hospital of Odontology. Results All 59 cases of facial trauma with damage to the peripheral facial nerve underwent facial nerve reconstruction surgery within 8 weeks of the injury. Of these cases, 25/59 (42.3%) had end-to-end anastomosis, 22/59 (37.3%) had nerve grafting, and 12/59 (20.4%) had a combination of nerve grafting and end-to-end anastomosis. After surgery, the rates of moderate and good recovery were 78.4% and 11.8%, respectively. All facial paralysis measurements showed statistically significant improvement after surgery, including the Facial Nerve Grading Scale 2.0 (FNGS 2.0) score, the Facial Clinimetric Evaluation (FaCE) scale, and electroneurography. The rate of synkinesis after surgery was 34%. Patient follow-up postoperatively ranged from 6 to > 36 months; 51 out of 59 patients (86.4%) were followed-up for at least 12 months or longer. Conclusion Nerve rehabilitation surgery including direct end-to-end anastomosis and nerve grafting is effective in cases of peripheral facial nerve injury following facial trauma. The surgery helps restore nerve conduction and improve facial paralysis.

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Macular holes (MHs), including atraumatic idiopathic and refractory MHs, affect central vision acuity due to full-thickness defects in the retinal tissue. The existing controversy regarding the pathophysiology and management of MHs has significantly improved with the implementation of internal limiting membrane (ILM) surgical techniques and improved MH closure rates. Thus, to determine the effect of ILM techniques on large idiopathic and refractory MH management, the present study systematically reviewed 5910 original research articles extracted from online literature databases, including PubMed, Cochrane, Google Scholar, and Embase, following the PRISMA guidelines. The primary outcome measures were MH closure rate and postoperative visual acuity. A total of 23 randomized controlled trials (RCTs) with adequate patient information and information on the effect of ILM peeling, inverted ILM flaps, autologous retinal transplantation (ART), and ILM insertion techniques on large idiopathic and refractory MH patients were retrieved and analyzed using RevMan software (version 5.3) provided by the Cochrane Collaboration. Statistical risk of bias analysis was also conducted on the selected sources using RoB2, which showed a low risk of bias in the included studies. A meta-analysis indicated that the inverted ILM flap technique had a significantly greater MH closure rate for primary MH than the other treatment methods (OR = 3. 22, 95% CI 1.34-7.43; p = 0.01). Furthermore, the findings showed that the inverted ILM flap group had significantly better postoperative visual acuity than did the other treatment options for patients with idiopathic MH (WMD = - 0.13; 95% CI = 0.22-0.09; p = 0.0002). The ILM peeling technique had the second highest statistical significance for MH closure rates in patients with idiopathic MH (OR = 2. 72, 95% CI: 1.26-6.32; p = 0.016). In refractory MHs, autologous retinal transplant (ART) and multilayer ILM plug (MIP) techniques improve the closure rate and visual function; human amniotic membrane grafting (hAMG) provides a high degree of anatomical outcomes but disappointing visual results. This study demonstrated the reliability and effectiveness of ILM techniques in improving the functional and anatomical outcomes of large idiopathic and refractory MH surgery. These findings will help clinicians choose the appropriate treatment technique for patients with idiopathic and refractory MH.

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Nosocomial infections or healthcare-associated infections, normally develops after the healthcare treatment in the hospital. Most of them are caused by infected medical devices. Plastics are the most common materials for manufacturing these devices because of their good processability, sterilization efficacy, ease of handling and harmlessness, however, it usually do not display antimicrobial properties. Here, in order to infer antimicrobial activity to poly(lactic acid), it was modified by maleation, followed by l-lysine grafting to its structure. The chemical modifications were confirmed by FTIR and 1H NMR analysis, indicating the success of the reactions. The antimicrobial activity was tested using Escherichia coli and Staphylococcus aureus and the results showed that the sample was capable of inhibiting about 99 % of the S. aureus growth by contact. The samples cytotoxicity was also tested using the L929 mouse cells and the results indicated no cytotoxic effect. These results indicated the sample antimicrobial potential, without affect the normal eukaryotic cells. In addition, the processability of the modified PLA (PLA-g-Lys) was improved without compromising its mechanical properties, as shown by thermal analysis and tensile tests. Thus, this novel PLA derivative can be seen as a promising material for future applications in the manufacturing of biomedical devices.

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The aim of this research was to graft gallic acid (GA) onto high methoxyl pectin (HMP) through the redox-pair of ascorbic acid (Aa) and hydrogen peroxide (H2O2) with one- and two-pot procedures. The effectiveness of the both procedures and the chemical, physical and antioxidant properties of the obtained HMP-GA were evaluated. HMP-GAone-pot (23.3 ± 0.21 mg GA Equivalent (GAE)/g) and HMP-GAtwo-pot (32.3 ± 0.52 mg GAE/g) were best obtained at H2O2/Aa molar ratio-HMP/GA weight ratio of 9.0-0.5 and 16.0-0.5, respectively. The UV-Vis and FT-IR spectra and along with their derivative and thermal gravimetric analyses, revealed differences between HMP-GAone-pot and HMP-GAtwo-pot. The latter exhibited a greater antioxidant capacity than the former in single electron transfer (ET), hydrogen atom transfer (HAT), and ET-HAT mixed assays. The chemical differences can be attributed to side reactions that may have interfered with the grafting reaction. Consequently, HMP-GA, possessing unique antioxidant and prebiotic properties, can be synthesized through redox-pair procedures.

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Background: Autologous fat transfer (AFT) is gaining popularity in breast surgery, offering a natural-looking and minimally invasive approach for augmentation, reconstruction, and contouring. However, concerns about its impact on breast cancer necessitate an understanding of the interplay between transplanted adipose-derived stem cells (ADSCs) and the breast tissue microenvironment. Renowned for regeneration, ADSCs raise questions about their role in cancer promotion. This systematic review delves into the complex relationship between AFT and breast cancer, exploring how ADSCs may influence development, growth, and metastasis. Methods: A systematic search of electronic databases, including PubMed, Embase, and BVS was conducted to identify relevant studies. The search strategy employed a combination of keywords, including "breast augmentation", "fat grafting", "breast enhancement", "mammoplasty", "cancer", "neoplasm" and related terms. Two reviewers independently screened titles and abstracts. Full-text articles were then retrieved for further evaluation based on their potential contribution to the review objectives. Results: Two hundred and forty records were identified. Among these, 104 duplicates were removed, resulting in 136 reports available for title and abstract screening. Subsequently, 54 papers were deemed potentially eligible for inclusion, and all reports were retrieved. Conclusions: In vitro studies reveal ADSCs dual role in breast cancer, influencing proliferation, migration, and drug resistance through complex signaling pathways. Animal studies highlight distinct ADSC subpopulations impacting tumor growth via direct interactions and extracellular vesicle cargo. In vivo, ADSC-enriched fat grafting is generally safe, showing no increased cancer recurrence risk compared to other methods. Notably, cases of invasive breast carcinoma warrant special attention. ADSC-enriched fat grafts exhibit potential benefits in graft retention and survival rates. Despite promising evidence, further studies are needed to comprehensively understand the intricate relationship between ADSCs and breast cancer for optimized clinical applications and potential therapeutic innovations.

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The purpose of this study was to evaluate the repair process in rat calvaria filled with synthetic biphasic bioceramics (Plenum® Osshp-70:30, HA:ßTCP) or autogenous bone, covered with a polydioxanone membrane (PDO). A total of 48 rats were divided into two groups (n = 24): particulate autogenous bone + Plenum® Guide (AUTOPT+PG) or Plenum® Osshp + Plenum® Guide (PO+PG). A defect was created in the calvaria, filled with the grafts, and covered with a PDO membrane, and euthanasia took place at 7, 30, and 60 days. Micro-CT showed no statistical difference between the groups, but there was an increase in bone volume (56.26%), the number of trabeculae (2.76 mm), and intersection surface (26.76 mm2) and a decrease in total porosity (43.79%) in the PO+PG group, as well as higher values for the daily mineral apposition rate (7.16 µm/day). Histometric analysis presented material replacement and increased bone formation at 30 days compared to 7 days in both groups. Immunostaining showed a similar pattern between the groups, with an increase in proteins related to bone remodeling and formation. In conclusion, Plenum® Osshp + Plenum® Guide showed similar and sometimes superior results when compared to autogenous bone, making it a competent option as a bone substitute.

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We evaluated the effect of periosteal-releasing incisions on flap displacement in anterior maxillary sites following implant placement and simultaneously guided bone regeneration. Thirty patients, each requiring a single dental implant and guided bone regeneration in the maxillary esthetic zone, were recruited. After full-thickness flap elevation, the displacement of the flap was measured under a standardized tension of 1 Ncm. Then, a 2-step periosteal releasing incision was placed in the internal aspect of the flap, and the displacement was remeasured using the same standardized tension. Keratinized tissue width and mucosal thickness at the surgical site were recorded. Patient-reported outcomes were assessed at the 7- and 14-day recall visits. Flap displacement (primary outcome) was calculated before and after periosteal-releasing incisions. Multivariable linear regression models were used to evaluate the influence of mucosal thickness on flap displacement and adjusted for Keratinized tissue width. Primary wound closure was achieved in all patients. The mean difference in flap coronal displacement before and after the periosteal-releasing incisions was 8.2 mm (p < .0001). Adjusted regression models showed no association between mucosal thickness and keratinized tissue width with the amount of flap displacement (p = .770). Patient-reported outcome measures for pain, swelling, and bleeding amounted to 1.28 ± 1.93, 1.36 ± 1.87, and 0.0 ± 0.0 at 7 days and 0.11 ± 0.57, 0.56 ± 1.03, and 0.0 ± 0.0 at 14 days, respectively. Periosteal-releasing incisions using the 2-step procedure described here are a predictable technique to obtain coronal flap displacements >8 mm without increased surgical complications.

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A polyethylene (PE) film surface modification method is proposed via benzoic acid (BA) alkylation grafting to improve the surface affinity to polar substances. The procedure involves sequentially spraying AlCl3 and BA onto the heat-softened PE surface. The occurrence of the alkylation reaction was evaluated through comparative chemical, morphological, and thermal analyses. It was demonstrated that the grafting reaction of BA onto the PE film surface took place, limited to the surface layer, while preserving the bulk properties of PE. The reaction resulted in the formation of aluminum benzoate complexes, which improved the surface affinity to polar compounds. The impact of grafting on the surface properties of PE was further assessed by comparing the behavior of PE films treated with BA and untreated PE films when painted with watercolors. The PE film grafted with BA exhibited increased affinity towards watercolors, providing strong evidence of a change in surface polarity from hydrophobic to hydrophilic. These findings indicate that the proposed methodology effectively renders the PE surface paintable, even with non-toxic water-based inks, making it suitable for applications such as packaging.

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OBJECTIVES: Coronary artery disease (CAD) and abdominal aortic aneurysm (AAA) are common arterial pathologies that might occur simultaneously; however, there is not enough evidence about the optimal strategy for patients with concomitant indications of coronary artery bypass grafting (CABG) and open repair of the AAA (AAOR). This study aims to present the outcomes in low and moderate cardiac surgical risk patients who underwent one-stage or two-stage elective CABG and AAOR in a middle-income country. METHODS: An observational, retrospective case series study was conducted. Patients who had low and moderate cardiac surgical risk (less than 8% mortality risk on the STS score) and had the concomitant indication for CABG and AAOR between December 2005 and August 2021 were included. Patients were assigned to one of three strategies: Group 1 underwent one-stage surgery for CABG and AAOR, Group 2 underwent two-stage surgery within the same in-patient stay, and Group 3 underwent two-stage surgery in a new in-patient stay within 6 months. RESULTS: Twenty seven, patients with simultaneous requirements of CABG and AAOR were identified, with a mean age of 69.5 ± 6.1 years and 92.6% were male. The most common comorbidities were hypertension at 77.8% and dyslipidemia at 55.6%. The average mortality risk calculated by the STS score was 2.09% ± 1.53%. In Group 1 (n = 9), 1/9 had in-hospital mortality and no reinterventions were needed. In Group 2 (n = 10), 1/10 had in-hospital mortality, and the most common postoperative complication was acute kidney injury 2/10. Furthermore, 2/10 required a reintervention. In Group 3 (n = 8), no in-hospital mortality was present, however, complications such as sepsis, atrial fibrillation, and acute kidney injury occurred in 2/8 patients each, and 2/8 required a reintervention. CONCLUSION: Patients with CAD and AAA that need a concomitant surgical correction with CABG and an AAOR are uncommon in contemporary practice, given the advances in endovascular therapy. When indicated, one-stage surgery can be performed in patients with low cardiac surgical risk, proper patient selection plays a fundamental role and might be performed in experienced centers. However, two-staged surgeries at the same or different inpatient stay may be considered for asymptomatic AAA with close monitoring during the postoperative period. These findings can hold significance for addressing sociodemographic barriers in low and middle-income countries. More robust and extensive studies are needed to make clear comparisons between the different strategies.

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Embolism resistance of xylem tissue varies among species and is an important trait related to drought resistance, with anatomical attributes like pit membrane thickness playing an important role in avoiding embolism spread. Grafted Citrus trees are commonly grown in orchards, with the rootstock being able to affect the drought resistance of the whole plant. Here, we evaluated how rootstocks affect the vulnerability to embolism resistance of the scion using several rootstock/scion combinations. Scions of 'Tahiti' acid lime, 'Hamlin', 'Pera' and 'Valencia' oranges grafted on a 'Rangpur' lime rootstock exhibit similar vulnerability to embolism. In field-grown trees, measurements of leaf water potential did not suggest significant embolism formation during the dry season, while stomata of Citrus trees presented an isohydric response to declining water availability. When 'Valencia' orange scions were grafted on 'Rangpur' lime, 'IAC 1710' citrandarin, 'Sunki Tropical' mandarin or 'Swingle' citrumelo rootstocks, variation in intervessel pit membrane thickness of the scion was found. The 'Rangpur' lime rootstock, which is known for its drought resistance, induced thicker pit membranes in the scion, resulting in higher embolism resistance than the other rootstocks. Similarly, the rootstock 'IAC 1710' citrandarin generated increased embolism resistance of the scion, which is highly relevant for citriculture.

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BACKGROUND/AIM: The epidermal growth factor receptor (EGFR) is over-expressed in several types of cancer, and monoclonal antibody therapy has been the strategy that has shown the best results. This study focused on the construction of a humanized single chain antibody (huscFv) directed against EGFR (HER1). MATERIALS AND METHODS: The CDR grafting method was used to incorporate murine complementarity determining regions (CDRs) of cetuximab into human sequences. A dot blot assay was used to examine the affinity of the huscFv secreted by HEK293T for EGFR. The inhibitory effect on the viability of A549 cells was evaluated using the WST-1 assay. RESULTS: The incorporation of murine CDRs of cetuximab into human sequences increased the degree of humanness by 16.4%. The increase in the humanization of scFv did not affect the affinity for EGFR. Metformin had a dose-dependent effect, with an IC50 of 46 mM, and in combination with huscFv, the cell viability decreased by 45% compared to the 15% demonstrated by huscFv alone. CONCLUSION: The CDR grafting technique is efficient for the humanization of scFv, maintaining its affinity for EGFR and demonstrating its inhibitory effect when combined with metformin in A549 cells.

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Chronic ulcers significantly affect the quality of life of patients and impose a high cost on the healthcare system. The therapeutic management should be comprehensive, taking into consideration the etiological diagnosis of the wound and the characteristics of the wound bed when deciding on a therapeutic proposal appropriate to the healing phase, correcting factors that delay healing. During the epithelialization phase, repair techniques with grafts are recommended to shorten re-epithelialization time, improve the quality of scar tissue, and achieve adequate pain management. Currently, due to the reported benefits of skin appendages, the technique of follicular unit auto-grafting obtained with a scalp punch is among the chosen strategies for wound repair. This is a minimally invasive, outpatient practice, whose technique has advantages over the donor site, patients recovery and well-being.

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Los quistes de los maxilares son las lesiones óseas más comunes en la región maxilofacial. La enucleación de las lesiones y el cierre primario de los defectos, son en conjunto, el tratamiento óptimo hoy en día. En algunas ocasiones el defecto óseo resultante puede ser de un tamaño tan grande que afecta la estabilidad de dientes vecinos, comprometa la indemnidad del hueso o produce un retraso cicatrizal que incluso puede impedir una regeneración ósea completa. Se considera que esta falta de regeneración expone al paciente a riesgos de infección tardía, retraso de los tratamientos rehabilitadores en zonas de alta demanda estética y pérdida de vitalidad dentaria. Para disminuir el riesgo de alteraciones en la regeneración ósea completa de cavidades quísticas, se ha propuesto la posibilidad de que tras la enucleación del quiste se rellenen estos defectos con injertos óseos u otras técnicas de preservación alveolar para favorecer la cicatrización. Teóricamente el uso de estos injertos mejora la calidad y disminuye el tiempo de cicatrización ósea, permitiendo que el paciente recupere rápidamente las funciones habituales del componente dentoalveolar, acortando el periodo de cuidados postoperatorios que restringen la alimentación, los deportes o la rehabilitación oral. El actual trabajo tiene como objetivo realizar una revisión de la literatura respecto a los beneficios del uso de injertos óseos en el tratamiento quirúrgico de los quistes maxilares y presentar un caso clínico con los detalles quirúrgicos de esta técnica.

Jaw cysts are the most common bone lesions in the maxillofacial region. Enucleation of the lesions along with the primary closure of the defects are the optimal treatment nowadays. On some occasions, the resulting bone defect can be so large that it affects the stability of neighboring teeth, compromises the integrity of the bone, or produces a delayed healing that can even prevent complete bone regeneration. It is considered that the lack of regeneration exposes the patient to risk of infection, delay of rehabilitation treatments in areas of high aesthetic demand and loss of dental vitality. To reduce the risk of alterations in complete bone regeneration of cystic cavities, the possibility of filling these defects with bone grafts or other alveolar preservation techniques to promote healing, has been proposed after cyst enucleation. Theoretically, the use of these grafts improves the quality and decreases the bone healing time, allowing the patient to quickly recover the usual functions of the dentoalveolar component, limiting the period of postoperative care that restricts eating, sports or oral rehabilitation. The present work aims to carry out a review of the literature regarding the benefits of the use of bone grafts in the surgical treatment of maxillary cysts and to present a clinical case with the surgical details of this technique.

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OBJECTIVES: Unexpected coronary artery bypass grafting (CABG) is occasionally required during aortic root replacement (ARR). However, the impact of unplanned CABG remains unknown. DESIGN: A single-center, retrospective observational study. SETTING: At university-affiliated tertiary hospital. PARTICIPANTS: All patients who underwent ARR from 2011 through 2022. INTERVENTIONS: Aortic root replacement with or without unplanned CABG. MEASUREMENTS AND MAIN RESULTS: A total of 795 patients underwent ARR. Among them, 131 (16.5%) underwent planned concomitant CABG, and 34 (4.3%) required unplanned CABG. The most common indication of unplanned CABG was ventricular dysfunction (33.3%), followed by disease pathology (25.6%), anatomy (15.4%), and surgical complications (10.3%). A vein graft to the right coronary artery was the most commonly performed bypass. Infective endocarditis and aortic dissection were observed in 27.8% and 12.8%, respectively. Prior cardiac surgery was seen in 40.3%. The median follow-up period was 4.3 years. Unplanned CABG was not associated with operative mortality (odds ratio [OR] 1.54, 95% CI 0.33-7.16, p = 0.58) or long-term mortality (hazard ratio 0.91, 95% CI 0.44-1.89, p = 0.81). Body surface area smaller than 1.7 was independently associated with an increased risk of unplanned CABG (OR 4.51, 95% CI 1.85-11.0, p < 0.001). CONCLUSIONS: Unplanned CABG occurred in 4.3% of patients during ARR, but was not associated with operative mortality or long-term mortality. A small body surface area was a factor associated with unplanned CABG.

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Radiation chemistry presents a unique avenue for developing innovative polymeric materials with desirable properties, eliminating the need for chemical initiators, which can be potentially detrimental, especially in sensitive sectors like medicine. In this investigation, we employed a radiation-induced graft polymerization process with N-vinylcaprolactam (NVCL) to modify lignocellulosic membranes derived from Agave salmiana, commonly known as maguey. The membranes underwent thorough characterization employing diverse techniques, including contact angle measurement, degree of swelling, scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier-transform infrared-attenuated total reflectance spectroscopy (FTIR-ATR), nuclear magnetic resonance (CP-MAS 13C-NMR), X-ray photoelectron spectroscopy (XPS), and uniaxial tensile mechanical tests. The membranes' ability to load and release an antimicrobial glycopeptide drug was assessed, revealing significant enhancements in both drug loading and sustained release. The grafting of PNVCL contributed to prolonged sustained release by decreasing the drug release rate at temperatures above the LCST. The release profiles were analyzed using the Higuchi, Peppas-Sahlin, and Korsmeyer-Peppas models, suggesting a Fickian transport mechanism as indicated by the Korsmeyer-Peppas model.

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Many feline species are currently threatened with extinction. Therefore, germplasm bank establishment has become imperative. However, cryoinjury and ischemia-reperfusion injury pose significant obstacles to both cryopreservation and xenotransplantation. In this regard, erythropoietin (Epo) represents a potential alternative strategy due to its properties. This study aimed to assess the incubation of domestic cat ovarian tissue in Epo, both before and after cryopreservation, and investigate its effectiveness in promoting revascularization following xenotransplantation. Sixteen ovaries from 8 healthy cats were sliced following elective bilateral ovariohysterectomy (OHE). Subsequently, 8 fragments measuring 3 mm³ each were obtained from the cortical region of each ovary. The fragments were allocated into 3 treatment groups: Cryo group, fragments were cryopreserved, thawed and immediately transplanted; Cryo + Epo group, fragments were first cryopreserved in nitrogen, thawed, incubated in Epo (100 IU) for 2h and transplanted; and the Epo + Cryo group, in which fragments were first incubated in Epo (100 IU) for 2h, cryopreserved, thawed and immediately transplanted. The fragments were then xenotransplanted into the dorsal subcutaneous region of ovariectomized female nude mice and retrieved at 7, 14, 21, and 28 days post-transplantation. The results indicated that Epo effectively enhanced follicular survival, preservation of viability, and tissue revascularization. The Epo + Cryo group displayed better revascularization rates on D14 and D21 post-transplantation and an increase in primordial and growing follicles on D28, the Cryo + Epo group exhibited significantly more follicles on D14 and D21, with fewer degenerated follicles.

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