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1.
Mikrochim Acta ; 191(6): 330, 2024 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-38744738

RESUMO

In view of a large number of people infected with Helicobacter pylori (H. pylori) with great harm followed, there is an urgent need to develop a non-invasive, easy-to-operate, and rapid detection method, and to identify effective sterilization strategies. In this study, highly specific nanoprobes with nanozyme activity, Ag@Pt nanoparticles (NPs) with the antibody, were utilized as a novel lateral flow immunoassay (LFIA). The optical label (Ag@Pt NPs) was enhanced by the introduction of the chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) and compared with a gold nanoparticles (Au NPs) optical label. Under the optimal condition, Ag@Pt-LFIA and TMB-enhanced Ag@Pt-LFIA for H. pylori were successfully established, two of which were over twofold and 100-fold more sensitive than conventional visual Au NP-based LFIA, respectively. Furthermore, Ag@Pt NPs with the antibody irradiated with NIR laser (808 nm) at a power intensity of 550 mW/cm2 for 5 min exhibited a remarkable antibacterial effect. The nanoprobes could close to bacteria through effective interactions between antibodies and bacteria, thereby benefiting photothermal sterilization. Overall, Ag@Pt NPs provide promising applications in pathogen detection and therapeutic applications.


Assuntos
Ligas , Helicobacter pylori , Nanopartículas Metálicas , Platina , Prata , Helicobacter pylori/efeitos da radiação , Helicobacter pylori/efeitos dos fármacos , Prata/química , Nanopartículas Metálicas/química , Platina/química , Ligas/química , Antibacterianos/farmacologia , Antibacterianos/química , Imunoensaio/métodos , Benzidinas/química , Ouro/química , Humanos , Esterilização/métodos , Limite de Detecção
3.
Biomacromolecules ; 25(5): 3178-3189, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38632677

RESUMO

Bioadhesives with all-inclusive properties for simultaneous strong and robust adhesion, cohesion, tracking, drug delivery, self-sterilization, and nontoxicity are still farfetched. Herein, a carbon dot (CD) is made to infuse each of the above-desired aspects with gelatin, an inexpensive edible protein. The CD derived through controlled hydrothermal pyrolysis of dopamine and terephthaldehyde retained -NH2, -OH, -COOH, and, most importantly, -CHO functionality on the CD surface for efficient skin adhesion and cross-linking. Facile fabrication of CD-gelatin bioadhesive through covalent conjugation of -CHO of the CD with -NH2 of gelatin through Schiff base formation was accomplished. This imparts remarkable self-healing attributes as well as excellent adhesion and cohesion evident from physicomechanical analysis in a porcine skin model. Improved porosity of the bioadhesive allows loading hemin as a model drug whose disembarkment is tracked with intrinsic CD photoluminescence. In a significant achievement, antibiotic-free self-sterilization of bioadhesive is demonstrated through visible light (white LED, 23 W)-irradiated photosensitization of the CD to produce reactive oxygen species for annihilation of both Gram-positive and Gram-negative bacteria with exceptional efficacy (99.9%). Thus, a comprehensive CD-gelatin bioadhesive for superficial and localized wound management is reported as a promising step for the transformation of the bioadhesive domain through controlled nanotization for futuristic clinical translations.


Assuntos
Carbono , Sistemas de Liberação de Medicamentos , Gelatina , Gelatina/química , Carbono/química , Animais , Suínos , Sistemas de Liberação de Medicamentos/métodos , Esterilização/métodos , Adesivos Teciduais/química , Adesivos Teciduais/farmacologia , Pele/metabolismo , Pele/efeitos dos fármacos
4.
J Hazard Mater ; 471: 134372, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38669933

RESUMO

Bioaerosol is one of the main ways to spread respiratory infectious diseases. In order to further improve the sterilization efficiency of copper-manganese-cerium oxide (CuMnCeOx), the post-treatment method based on acid etching was adopted. The results showed that sterilization efficiency of the treated CuMnCeOx could reach 99% in aerosol with space velocity of 1400 h-1. L(+)-ascorbic acid successfully promoted the formation of Cu+, oxygen vacancies and the generation of reactive oxygen species (ROS) on the surface of the treated CuMnCeOx. During sterilization in liquid system, the transcriptome identified 316 differentially expressed genes, including 270 up-regulated genes and 46 down-regulated genes. Differentially expressed genes were significantly enriched in cell wall (GO:0005618) and external encapsulating structure (GO:0030312). Up-regulated genes were shown in regulation of reactive oxygen species biosynthetic processes (GO:1903409, GO:1903426, GO:1903428) and positive regulation all of reactive oxygen species metabolic process (GO:2000379), indicating that ROS induced cell death by destroying cell wall.


Assuntos
Aerossóis , Cobre , Manganês , Espécies Reativas de Oxigênio , Esterilização , Cobre/química , Espécies Reativas de Oxigênio/metabolismo , Esterilização/métodos , Manganês/química , Óxidos/química , Transcriptoma/efeitos dos fármacos
5.
Chemosphere ; 357: 141915, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582162

RESUMO

Standard OECD tests are used to generate data on biodegradation (OECD 307) and sorption (OECD 106) of test chemicals in soil. In such tests, data on abiotic degradation using sterile samples are utilised to investigate any losses due to abiotic processes. The data from sterile samples are also used to interpret results and findings of non-sterile samples, especially in the context of sorption and non-extractable residue (NER) formation. However, to ensure the comparability of the data obtained from sterile and non-sterile experiments, effects of sterilisation on the soil matrix should be minimal. The objective of this study was to investigate the efficiencies of different sterilisation techniques and the impact of the sterilisation on sorption and NER formation in soil. In this study, experiments in accordance with OECD 307 and OECD 106 guidelines were performed with two soils covering wide range of soil characteristics and treated with the three sterilisation techniques autoclaving, gamma(γ)-radiation and adding 1% (w/w) sodium azide. As a test item, 14C-labelled phenanthrene and bromoxynil was used for OECD 307 test, whereas non-labelled phenanthrene and atrazine was used for OECD 106. The sterilisation efficiencies were investigated using traditional viable plate count and molecular approaches (RNA extraction method). The results suggest that none of the tested techniques resulted in completely sterilised soil with autoclaving being the most efficient technique. Adding sodium azide led to most inefficient sterilisation and a significant increase (0.56 units) in soil pH. OECD 307 results showed differences in NER formation of the test chemicals, especially for soil poisoning and γ-radiation, which could be due to inefficient sterilisation and/or change in soil physico-chemical properties. OECD 106 results suggest that none of the sterilisation techniques considerably affected sorption behaviour of the test chemicals. Based on our results, we recommend autoclaving as most suitable sterilisation technique.


Assuntos
Biodegradação Ambiental , Poluentes do Solo , Solo , Esterilização , Poluentes do Solo/química , Poluentes do Solo/análise , Esterilização/métodos , Solo/química , Adsorção , Raios gama , Fenantrenos/química
6.
Klin Monbl Augenheilkd ; 241(4): 392-397, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38653293

RESUMO

PURPOSE: To introduce a novel technique of the aseptic manufacture of autologous serum eye drops (ASEDs) with a prefiltered closed system and to analyze the sterility of the produced ophtioles between 2018 and 2022. METHODS: This is a prospective single-center study conducted at the Department of Ophthalmology at a Swiss University Hospital between 2018 and 2022. For regulatory reasons, closed systems for manufacturing ASEDs are strongly recommended. We attached an upstream sterile filter (Sterivex PES0.22 µm Burlington, USA) to a commercially available closed system (COL System Modena, Italy) for manufacturing ASEDs. The goal of this novel approach was to reduce the microbiological contamination of the donated autologous blood. Using the presented manufacturing method, we are able to produce, on average, 56 ophtioles per batch, containing either 1.45 mL or 2.5 mL of autologous serum per ophtiole. For each batch of ASEDs, we performed a microbiological analysis by automated blood culture testing (BACTEC). This system examines the presence of bacteria and fungi. RESULTS: We analyzed all manufactured batches between 2018 and 2022. None of the 2297 batches and the resulting 129 060 ophtioles showed bacterial or mycotic contamination. During the analyzed period, two batches were discarded: one due to fibrin-lipid aggregations, further microbiological and histological work-up excluded any contamination; another due to false-positive HIV in serological testing. Overall, the contamination rate was 0%, and the batch discharge rate was 0.09%. CONCLUSIONS: The combination of upstream sterile filtration with a commercial closed system for manufacturing ASEDs proved to be effective in ensuring sterility without any contamination over the past 4 years. This is becoming crucial, as the demand for autologous blood products for treating ocular surface disorders, such as refractory dry eyes or nonhealing defects of the corneal epithelium, is on the rise.


Assuntos
Contaminação de Medicamentos , Soluções Oftálmicas , Soro , Humanos , Contaminação de Medicamentos/prevenção & controle , Estudos Prospectivos , Esterilização/métodos , Assepsia/métodos
7.
Int J Mol Sci ; 25(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38673921

RESUMO

In this present study, the material science background of crosslinked gelatin (GEL) was investigated. The aim was to assess the optimal reaction parameters for the production of a water-insoluble crosslinked gelatin matrix suitable for heat sterilization. Matrices were subjected to enzymatic degradation assessments, and their ability to withstand heat sterilization was evaluated. The impact of different crosslinkers on matrix properties was analyzed. It was found that matrices crosslinked with butanediol diglycidyl ether (BDDE) and poly(ethylene glycol) diglycidyl ether (PEGDE) were resistant to enzymatic degradation and heat sterilization. Additionally, at 1 v/v % crosslinker concentration, the crosslinked weight was lower than the starting weight, suggesting simultaneous degradation and crosslinking. The crosslinked weight and swelling ratio were optimal in the case of the matrices that were crosslinked with 3% and 5% v/v BDDE and PEGDE. FTIR analysis confirmed crosslinking, and the reduction of free primary amino groups indicated effective crosslinking even at a 1% v/v crosslinker concentration. Moreover, stress-strain and compression characteristics of the 5% v/v BDDE crosslinked matrix were comparable to native gelatin. Based on material science measurements, the crosslinked matrices may be promising candidates for scaffold development, including properties such as resistance to enzymatic degradation and heat sterilization.


Assuntos
Reagentes de Ligações Cruzadas , Resinas Epóxi , Gelatina , Água , Gelatina/química , Reagentes de Ligações Cruzadas/química , Água/química , Polietilenoglicóis/química , Temperatura Alta , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Teste de Materiais , Espectroscopia de Infravermelho com Transformada de Fourier , Solubilidade , Esterilização/métodos
8.
Int J Biol Macromol ; 266(Pt 2): 131395, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582460

RESUMO

Diabetic wounds are a significant clinical challenge. Developing effective antibacterial dressings is crucial for preventing wound ulcers caused by bacterial infections. In this study, a self-healing antibacterial hydrogel (polyvinyl alcohol (PVA)-polylysine-gum arabic, PLG hydrogels) with near-infrared photothermal response was prepared by linking PVA and a novel polysaccharide-amino acid compound (PG) through borate bonding combined with freeze-thaw cycling. Subsequently, the hydrogel was modified by incorporating inorganic nanoparticles (modified graphene oxide (GM)). The experimental results showed that the PLGM3 hydrogels (PLG@GM hydrogels, 3.0 wt%) could effectively kill bacteria and promote diabetic wound tissue healing under 808-nm near-infrared laser irradiation. Therefore, this hydrogel system provides a new idea for developing novel dressings for treating diabetic wounds.


Assuntos
Goma Arábica , Hidrogéis , Polilisina , Álcool de Polivinil , Cicatrização , Cicatrização/efeitos dos fármacos , Álcool de Polivinil/química , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Polilisina/química , Polilisina/farmacologia , Goma Arábica/química , Goma Arábica/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Diabetes Mellitus Experimental , Ratos , Esterilização/métodos , Masculino , Camundongos , Grafite/química , Grafite/farmacologia
9.
Med Sci Monit ; 30: e942601, 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38493296

RESUMO

BACKGROUND Central sterile supply departments (CSSDs) play a vital role in hospital infection control. We investigate the factors associated with wet pack occurrence after steam sterilization. MATERIAL AND METHODS We designed a log sheet to record information concerning sterilized packs. The data included the type of sterilized pack; outside weather (sunny, overcast, or rainy); the item in the sterilized pack; packaging material; whether the item had been packaged in compliance with guidelines; whether the pack had been laid flat, upright, or leaning at an acute angle; which sterilizer was used for sterilization of the pack; whether the pack had been placed on the top or bottom shelf inside the sterilizer chamber; whether the pack had been loaded in compliance with guidelines; the drying time following sterilization; and cooling time after sterilization. The sterilized packs in our study were selected from all of the packs that were sterilized in the CSSD of the authors' institution during June to December 2021. RESULTS Factors associated with wet pack occurrence after steam sterilization include: outside weather on the day of sterilization; the item in the sterilized pack; packaging material; whether the item had been packaged in compliance with guidelines; whether the pack had been placed on the top or bottom shelf; and cooling time after sterilization. Statistically significant differences (P<0.05) in wet pack incidence were identified for all of these factors. CONCLUSIONS Various factors are associated with wet pack occurrence after steam sterilization. Recommendations for reducing the risk of wet packs include regular maintenance of the steam pipeline, regular replacement of thermal insulation materials for the steam pipeline, and extension of the drying time.


Assuntos
Vapor , Esterilização , Incidência , Esterilização/métodos , Hospitais , China/epidemiologia
10.
Orthopadie (Heidelb) ; 53(5): 341-347, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38498205

RESUMO

BACKGROUND: The use of allografts and autografts has been met with mixed views on whether allografts are a suitable alternative to autografts. QUESTION: We aimed to investigate if chemically sterilized allografts show similar rerupture rates to those reported in the literature for allografts and autografts in anterior (ACL) and posterior cruciate ligaments (PCL) and complex knee surgery. MATERIALS AND METHODS: Retrospective data on knee reconstructions performed between 2011 and 2015 with tendon/ligamnet allografts sterilized with peracetic acid were collected in the form of a questionnaire. The inclusion criteria of 2 years for each patient were met by 38 patients, representing 22 ACL reconstructions, 5 PCL reconstructions, 3 OTHER surgeries, including the Larson technique and medial patellofemoral ligament (MPFL) reconstruction and 8 COMPLEX surgeries. The main endpoints were rerupture and complication rate. Secondary endpoints included stability of the knee (Lachman test, Pivot shift test) and the range of motion. RESULTS: The rerupture rate was 7.9% (3 grafts). Reruptures only occurred in the ACL group. No reruptures were observed in the PCL, OTHER and COMPLEX surgery groups. Stability improved significantly after surgery and the range of motion returned to values similar to that of healthy knees. CONCLUSIONS: Tendon allografts sterilized with peracetic acid show promising low rerupture rates and good clinical scores and the results are comparable to the literature on autografts and other allografts.


Assuntos
Aloenxertos , Ácido Peracético , Esterilização , Tendões , Humanos , Masculino , Feminino , Estudos Retrospectivos , Adulto , Tendões/transplante , Pessoa de Meia-Idade , Esterilização/métodos , Reconstrução do Ligamento Cruzado Anterior/métodos , Reconstrução do Ligamento Cruzado Posterior/métodos , Ligamento Cruzado Posterior/cirurgia , Transplante Homólogo/métodos
11.
AORN J ; 119(4): P4-P6, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38536412
12.
Int J Prosthodont ; 37(1): 109, 2024 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381989

RESUMO

PURPOSE: To determine and compare the frequency of contamination on different sites of healing abutments (HAs) after sterilization with Phloxine B dye on unused and used HAs after sterilization. MATERIALS AND METHODS: A total of 60 HAs were divided into two test groups: (1) used and sterilized and (2) a control group (unused). The test group was evaluated for contamination after sterilization; the control group did not undergo any procedure. Data were analyzed using SPSS version 22 (IBM). Descriptive statistics were used to determine the frequency of contamination in the different groups and at the different HA sites. Chi-square test was used to evaluate the association of frequency of contamination with the HA site and design. The level of significance was kept at P ≤ .01. RESULTS: The test group showed more contamination compared to the control group. The most contaminated sites were the screw thread and the screwdriver engagement location. CONCLUSIONS: HA reuse is cost-effective, but cleaning and sterilization was not effective for these components; thus, HAs need to be reused with caution because they were heavily contaminated when compared to new HAs. Among the different sites, the screw thread and screwdriver engagement sites were more prone to contamination. HA type did not influence the frequency of contamination.


Assuntos
Dente Suporte , Implantes Dentários , Propriedades de Superfície , Reutilização de Equipamento , Esterilização/métodos , Contaminação de Equipamentos
13.
Food Chem ; 445: 138670, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38422866

RESUMO

Heat sterilization enhances the safety and shelf-life of braised chicken, but its impact on protein digestibility and the release of metabolites remains unclear. Here, braised chicken was sterilized at 80 °C (LS), 100 °C (MS), and 121 °C (HS) for 30 min. Protein digestibility was assessed by in vitro digestion, whereas the release of metabolites was analysed by UPLC-QTOF-MS spectroscopy. Results revealed that LS had higher gastrointestinal digestibility (88.86 %) than MS (81.79 %) and HS (78.13 %). Increased carbonyl content, turbidity, particle size, and hydrophobicity, along with decreased sulfhydryl content and solubility, indicated rising protein oxidation aggregation with higher sterilization temperatures, explaining reduced digestibility. 96 metabolites were identified. Compared to the control group, LS exhibited a statistically significant variation in the biosynthesis of unsaturated fatty acids, MS displayed a significant difference in purine metabolism, and HS showed a significant difference in primary bile acid biosynthesis. Thus, LS is a promising sterilization method.


Assuntos
Galinhas , Temperatura Alta , Animais , Esterilização/métodos , Interações Hidrofóbicas e Hidrofílicas , Digestão
14.
Sci Rep ; 14(1): 3764, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355779

RESUMO

This study aimed to reduce instrument packaging defects in the Central Sterile Supply Department (CSSD) using action research. Data of the instrument packs packaged by the packaging personnel at the CSSD of the authors' institution during March to May 2023 were collected and analyzed. After identifying the problems, 2 rounds of cyclic process of "plan-action-observe-reflect" were implemented to standardize the packaging procedures and develop and improve the applicable check of standard operating procedures for the CSSD. After strictly implementing the packaging operation standards and checklists, the number of packaging defect cases dropped from 274 to 41. A significant difference was identified between the number of packaging personnel who achieved a "pass" in the assessment of 3 items for maintenance. Also, 1 item for assembly had significant differences compared with the baseline number after the first cycle (P ≤ 0.001). A significant difference was identified between the number of packaging personnel who achieved a "pass" in the assessment of 20 items for 6 components after the second cycle compared with that after the first cycle (P ≤ 0.05). Through action research methodology, strict implementation of standardized packaging procedures in the CSSD can reduce packaging defects, thereby decreasing clinical complaints and ensuring patient safety.


Assuntos
Melhoria de Qualidade , Esterilização , Humanos , Esterilização/métodos , Embalagem de Produtos , Embalagem de Medicamentos , Instalações de Saúde
15.
Sci Rep ; 14(1): 1253, 2024 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-38218988

RESUMO

The introduction of fish skin as a biological dressing for treating burns and wounds holds great promise, offering an alternative to existing management strategies. However, the risk of disease transmission is a significant concern. Therefore, this study aimed to examine how established sterilization and preservation procedures affected fish skin grafts' microbiological and histological properties for long-term usage. Lyophilization of the fish skin graft followed by rehydration in normal saline for 15 min did not change the collagen content. Furthermore, gamma irradiation of the lyophilized fish skin graft at different lengths 5, 10, and 25 KGy showed a significant reduction in microbial growth (aerobic bacteria, aerobic yeasts, and fungi) at 15- and 30 days after the irradiation. However, exposure to 10 KGy was found to be the most effective intensity among the different gamma irradiation lengths since it preserved the collagen fiber content and intensity in the lyophilized fish skin grafts at 15- and 30 days after the irradiation. These findings provide efficient preservation and sterilization methods for long-term usage of the fresh Tilapia skin grafts used for biological dressings.


Assuntos
Ictiose Lamelar , Transplante de Pele , Animais , Preservação Biológica , Liofilização , Colágeno , Peixes , Esterilização/métodos
16.
Am J Infect Control ; 52(3): 324-330, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37741293

RESUMO

BACKGROUND: The purpose of this process and quality improvement activity was to address opportunities identified with cleaning, disinfection, and sterilization requirements for eye devices, and implement a robust and sustainable processing system to support safe patient care. METHODS: Through the lean 6 Sigma methodology, the evaluation of noncritical, semicritical and critical device processing was conducted. A hierarchal approach to law, regulation, manufacturer's instructions for use, evidence-based guidelines, consensus documents, facility risk assessments, policy, and procedure was conducted. Over 15 diverse clinical areas within a large health care network were assessed for utilization of ophthalmic and optometric devices, with the review of inventory for manufacturer-instructed cleaning, disinfection and sterilization compliance. RESULTS: An interdepartmental multidisciplinary team with oversight of over 10 service lines led the implementation of point-of-use treatment, transport, high-level disinfection, sterilization, storage, and documentation based on intended use. CONCLUSIONS: During this experience, infection Preventionists performed a vital role in supporting a highly reliable cleaning, disinfection, and sterilization process. This undertaking required a team approach to apply instructions for uses and evidence-based practice that promoted sustainability and ultimately led to supporting the prevention of health care-associated infections and patient harm.


Assuntos
Infecção Hospitalar , Ilusões Ópticas , Humanos , Esterilização/métodos , Desinfecção/métodos , Infecção Hospitalar/prevenção & controle , Instalações de Saúde , Políticas
17.
J Biomater Appl ; 38(6): 721-732, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38031885

RESUMO

A commercial bacterial cellulose-monolaurin wound dressing was investigated for changes in the chemical structure, mechanical strength, thermal degradation, morphology, and functional swelling properties after exposure to gamma and electron beam radiations at doses 15-50 kGy. Radiation-induced oxidation occurred as seen in the FT-IR peaks at 1720-1750 cm-1. Degradation of the cellulosic network was observed in tensile strength reduction and shift in degradation temperature to lower values. The SEM cross-section images of the irradiated dressings revealed a less dense nanostructure network compared to the non-irradiated samples while the XRD diffractograms indicated a change in lattice direction/plane. Despite these changes, irradiation caused no significant effect on the functional properties especially at 15-25 kGy doses where most biomedical devices are sterilized. All irradiated wound dressings exhibited physical integrity, increased exudate absorption, and water vapor transmission rate - properties beneficial to wound-healing functionality. The pre-selected sterilization dose of 15 kGy for each ionizing radiation was successfully verified and substantiated following ISO 11137-2:2016, hence ionizing radiation is a suitable sterilization modality for the product.


Assuntos
Bactérias , Bandagens , Espectroscopia de Infravermelho com Transformada de Fourier , Esterilização/métodos
18.
J Biomed Mater Res A ; 112(6): 825-840, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38158889

RESUMO

Acellular porcine cornea (APC) has been used in corneal transplantation and treatment of the corneal diseases. Sterilization is a key step before the application of graft, and irradiation is one of the most commonly used methods. In this paper, APC was prepared by the physical freeze-thawing combined with biological enzymes, and the effects of the electron beam (E-beam) and cobalt 60 (60Co-γ) at the dose of 15 kGy on the physicochemical properties, structure, immunogenicity, and biocompatibility of the APC were investigated. After decellularization, the residual DNA was 20.86 ± 1.02 ng/mg, and the α-Gal clearance rate was more than 99%. Irradiation, especially the 60Co-γ, reduced the cornea's transmittance, elastic modulus, enzymatic hydrolysis rate, swelling ratio, and cross-linking degree. Meanwhile, the diameter and spacing of the collagen fibers increased. In the rat subcutaneous implantation, many inflammatory cells appeared in the unirradiated APC, while the irradiated had good histocompatibility, but the degradation was faster. The lamellar keratoplasty in rabbits indicated that compared to the E-beam, the 60Co-γ damaged the chemical bond of collagen to a larger extent, reduced the content of GAGs, and prolonged the complete epithelization of the grafts. The corneal edema was more serious within 1 month after the surgery. After 2 months, the thickness of the APC with the two irradiation methods tended to be stable, but that in the 60Co-γ group became thinner. The pathological results showed that the collagen structure was looser and the pores were larger, indicating the 60Co-γ had a more extensive effect on the APC than the E-beam at 15 kGy.


Assuntos
Transplante de Córnea , Elétrons , Suínos , Coelhos , Animais , Ratos , Córnea , Transplante de Córnea/métodos , Esterilização/métodos , Colágeno/análise
19.
J Biomech ; 162: 111904, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38134466

RESUMO

The role of donor-derived tendons, also known as allografts, in anterior cruciate ligament replacement surgeries is steadily increasing. Before surgery, temporary storage and, in most cases, sterilization are essential. It is, thus, crucial to determine how these procedures alter the grafts' biomechanical properties. The purpose of this research was to analyze the effect of different sterilization methods (native, frozen, frozen + 21 kGy gamma irradiation, frozen + 21 kGy electron beam irradiation) and storage durations (0 to 4 months) on the deformation and creep of two tendon types (tibialis anterior, peroneus longus). 80 tibialis anterior and 83 peroneus longus tendons from 51 human cadavers were included. The samples were removed, placed in a radio-cryoprotectant solution, then slowly cooled, sterilized and stored at -80 °C. All groups were subject to 60 s static creep test with 250 N load. Deformation during the loading phase, creep during static loading, and the ratio of these two were evaluated. Deformation at the end of the loading phase and creep consistently exhibited significantly smaller values in the tibialis anterior compared to the peroneus longus type, as well as in electron beam-sterilized grafts as opposed to gamma beam-sterilized ones. Prolonged storage periods (within 0 to 4 months) resulted in a notable increase in these values, particularly in deformation. Based on the experimental data, the tibialis anterior tendon type and sterilization by gamma beam irradiation are better choices for anterior cruciate ligament reconstruction than the peroneus longus and sterilization by electron beam. Increased storage time affects negatively the evaluated mechanical properties.


Assuntos
Lesões do Ligamento Cruzado Anterior , Tendões , Humanos , Fenômenos Biomecânicos , Transplante Homólogo/métodos , Tendões/transplante , Esterilização/métodos , Aloenxertos/efeitos da radiação
20.
Appl Environ Microbiol ; 90(1): e0132923, 2024 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-38112445

RESUMO

Common sterilization techniques for labile and sensitive materials have far-reaching applications in medical, pharmaceutical, and industrial fields. Heat inactivation, chemical treatment, and radiation are established methods to inactivate microorganisms, but pose a threat to humans and the environment and can damage susceptible materials or products. Recent studies have demonstrated that cold low-pressure plasma (LPP) treatment is an efficient alternative to common sterilization methods, as LPP's levels of radicals, ions, (V)UV-radiation, and exposure to an electromagnetic field can be modulated using different process gases, such as oxygen, nitrogen, argon, or synthetic (ambient) air. To further investigate the effects of LPP, spores of the Gram-positive model organism Bacillus subtilis were tested for their LPP susceptibility including wild-type spores and isogenic spores lacking DNA-repair mechanisms such as non-homologous end-joining (NHEJ) or abasic endonucleases, and protective proteins like α/ß-type small acid-soluble spore proteins (SASP), coat proteins, and catalase. These studies aimed to learn how spores resist LPP damage by examining the roles of key spore proteins and DNA-repair mechanisms. As expected, LPP treatment decreased spore survival, and survival after potential DNA damage generated by LPP involved efficient DNA repair following spore germination, spore DNA protection by α/ß-type SASP, and catalase breakdown of hydrogen peroxide that can generate oxygen radicals. Depending on the LPP composition and treatment time, LPP treatment offers another method to efficiently inactivate spore-forming bacteria.IMPORTANCESurface-associated contamination by endospore-forming bacteria poses a major challenge in sterilization, since the omnipresence of these highly resistant spores throughout nature makes contamination unavoidable, especially in unprocessed foods. Common bactericidal agents such as heat, UV and γ radiation, and toxic chemicals such as strong oxidizers: (i) are often not sufficient to completely inactivate spores; (ii) can pose risks to the applicant; or (iii) can cause unintended damage to the materials to be sterilized. Cold low-pressure plasma (LPP) has been proposed as an additional method for spore eradication. However, efficient use of LPP in decontamination requires understanding of spores' mechanisms of resistance to and protection against LPP.


Assuntos
Bacillus subtilis , Esporos Bacterianos , Humanos , Bacillus subtilis/genética , Catalase/metabolismo , Esporos Bacterianos/fisiologia , Esterilização/métodos , Proteínas/metabolismo , Temperatura Alta , DNA/metabolismo
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