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Chronic wounds are susceptible to bacterial infections and at high risk of developing antibiotic-resistant bacterial infections. Silver is an antimicrobial by targeting almost all types of bacteria in chronic wounds to reduce the bacterial load in the infected area and further facilitate the healing process. This study focused on exploring whether silver-based dressings were superior to non-silver dressings in the treatment of chronic wounds. PubMed, Web of Science and Embase were comprehensively searched from inception to March 2024 for randomized clinical trials and observational studies. The endpoints in terms of wound healing rate, complete healing time, reduction on wound surface area and wound infection rate were analysed using Review Manager 5.4 software. A total of 15 studies involving 5046 patients were eventually included. The results showed that compared with patients provided with non-silver dressings, patients provided with silver-based dressings had higher wound healing rate (OR: 1.43, 95% CI: 1.10-1.85, p = 0.008), shorter complete healing time (MD: -0.96, 95% CI: -1.08 ~ -0.85, p < 0.00001) and lower wound infection rate (OR: 0.56, 95% CI: 0.40-0.79, p = 0.001); no significant difference in the reduction on wound surface area (MD: 12.41, 95% CI: -19.59-44.40, p = 0.45) was found. These findings suggested that the silver-based dressings were able to enhance chronic wound healing rate, shorten the complete healing time and reduce wound infection rate, but had no significant improvement in the reduction on wound surface area. Large-scale and rigorous studies are required to confirm the beneficial effects of silver-based dressings on chronic wound healing.
Assuntos
Bandagens , Prata , Cicatrização , Humanos , Cicatrização/efeitos dos fármacos , Prata/uso terapêutico , Prata/farmacologia , Doença Crônica , Infecção dos Ferimentos/tratamento farmacológico , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Adulto , Compostos de Prata/uso terapêutico , Compostos de Prata/farmacologiaRESUMO
The repair of infected wounds is a complex physiopathologic process. Current studies on infected wound treatment have predominantly focused on infection treatment, while the factors related to delayed healing caused by vascular damage and immune imbalance are commonly overlooked. In this study, an extracellular matrix (ECM)-like dynamic and multifunctional hyaluronic acid (HA) hydrogel with antimicrobial, immunomodulatory, and angiogenic capabilities was designed as wound dressing for the treatment of infected skin wounds. The dynamic network in the hydrogel dressing was based on reversible metal-ligand coordination formed between sulfhydryl groups and bioactive metal ions. In our design, antibacterial silver and immunomodulatory zinc ions were employed to coordinate with sulfhydrylated HA and a vasculogenic peptide. In addition to the desired bioactivities for infected wounds, the hydrogel could also exhibit self-healing and injectable abilities. Animal experiments with infected skin wound models indicated that the hydrogel dressings enabled minimally invasive injection and seamless skin wound covering and then facilitated wound healing by efficient bacterial killing, continuous inflammation inhibition, and improved blood vessel formation. In conclusion, the metal ion-coordinated hydrogels with wound-infection-desired bioactivities and ECM-like dynamic structures represent a class of tissue bionic wound dressings for the treatment of infected and chronic inflammation wounds.
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Dermatite , Infecções , Ligantes , Hidrogéis/química , Zinco/química , Zinco/uso terapêutico , Cátions/química , Prata/química , Prata/uso terapêutico , Cicatrização , Dermatite/tratamento farmacológico , Infecções/tratamento farmacológico , Neovascularização Patológica , Fatores Imunológicos/uso terapêutico , Antibacterianos/uso terapêutico , Animais , Camundongos , Ratos , Linhagem CelularRESUMO
Due to the limitations of single-model tumor therapeutic strategies, multimodal combination therapy have become a more favorable option to enhance efficacy by compensating for its deficiencies. However, in nanomaterial-based multimodal therapeutics for tumors, exploiting synergistic interactions and cascade relationships of materials to achieve more effective treatments is still a great challenge. Based on this, we constructed a nanoplatform with a "triple-linkage" effect by cleverly integrating polydopamine (PDA), silver nanoparticles (AgNPs), and glucose oxidase (GOx) to realize enhanced photothermal therapy (PTT) and activatable metal ion therapy (MIT) for hepatocellular carcinoma (HCC) treatment. First, the non-radiative conversion of PDA under light conditions was enhanced by AgNPs, which directly enhanced the photothermal conversion efficiency of PDA. In addition, GOx reduced the synthesis of cellular heat shock proteins by interfering with cellular energy metabolism, thereby enhancing cellular sensitivity to PTT. On the other hand, H2O2, a by-product of GOx-catalyzed glucose, could be used as an activation source to activate non-toxic AgNPs to release cytotoxic Ag+, achieving activatable Ag+-mediated MIT. In conclusion, this nanosystem achieved efficient PTT and MIT for HCC by exploiting the cascade effect among PDA, AgNPs, and GOx, providing a novel idea for the design of multimodal tumor therapeutic systems with cascade regulation.
Assuntos
Carcinoma Hepatocelular , Glucose Oxidase , Indóis , Neoplasias Hepáticas , Nanopartículas Metálicas , Terapia Fototérmica , Polímeros , Prata , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Prata/química , Prata/farmacologia , Prata/uso terapêutico , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Humanos , Glucose Oxidase/metabolismo , Indóis/química , Indóis/farmacologia , Indóis/uso terapêutico , Animais , Terapia Fototérmica/métodos , Camundongos , Polímeros/química , Linhagem Celular Tumoral , Fototerapia/métodos , Camundongos Endogâmicos BALB C , Peróxido de Hidrogênio , Sobrevivência Celular/efeitos dos fármacos , Camundongos NusRESUMO
Conventional wound approximation devices, including sutures, staples, and glues, are widely used but risk of wound dehiscence, local infection, and scarring can be exacerbated in these approaches, including in diabetic and obese individuals. This study reports the efficacy and quality of tissue repair upon photothermal sealing of full-thickness incisional skin wounds using silk fibroin-based laser-activated sealants (LASEs) containing copper chloride salt (Cu-LASE) or silver nanoprisms (AgNPr-LASE), which absorb and convert near-infrared (NIR) laser energy to heat. LASE application results in rapid and effective skin sealing in healthy, immunodeficient, as well as diabetic and obese mice. Although lower recovery of epidermal structure and function was seen with AgNPr-LASE sealing, likely because of the hyperthermia induced by laser and presence of this material in the wound space, this approach resulted in higher enhancement in recovery of skin biomechanical strength compared to sutures and Cu-LASEs in diabetic, obese mice. Histological and immunohistochemical analyses revealed that AgNPr-LASEs resulted in significantly lower neutrophil migration to the wound compared to Cu-LASEs and sutures, indicating a more muted inflammatory response. Cu-LASEs resulted in local tissue toxicity likely because of effects of copper ions as manifested in the form of a significant epidermal gap and a 'depletion zone', which was a region devoid of viable cells proximal to the wound. Compared to sutures, LASE-mediated sealing, in later stages of healing, resulted in increased angiogenesis and diminished myofibroblast activation, which can be indicative of lower scarring. AgNPr-LASE loaded with vancomycin, an antibiotic drug, significantly lowered methicillin-resistant Staphylococcus aureus (MRSA) load in a pathogen challenge model in diabetic and obese mice and also reduced post-infection inflammation of tissue compared to antibacterial sutures. Taken together, these attributes indicate that AgNPr-LASE demonstrated a more balanced quality of tissue sealing and repair in diabetic and obese mice and can be used for combating local infections, that can result in poor healing in these individuals.
Assuntos
Diabetes Mellitus Experimental , Pele , Cicatrização , Animais , Cicatrização/efeitos dos fármacos , Diabetes Mellitus Experimental/complicações , Camundongos , Pele/efeitos dos fármacos , Pele/patologia , Camundongos Obesos , Lasers , Obesidade/complicações , Camundongos Endogâmicos C57BL , Adesivos Teciduais/farmacologia , Adesivos Teciduais/uso terapêutico , Cobre/química , Prata/química , Prata/farmacologia , Prata/uso terapêutico , Fibroínas/química , Fibroínas/farmacologia , MasculinoRESUMO
Burn is a debilitating and devastating emergency with many physical and psychological sequelae. Essential steps in burn wound management include cleansing/wound debridement, application of topical antimicrobial and dressing of affected body areas. Objective of this study is comparison in effectiveness of Hydro-fiber Silver dressing and 1% silver sulfadiazine dressing in management of pediatric burn patients in terms of wound healing. After ethical approval, 264 patients were enrolled and divided into two groups. Patients were managed with hydro-fiber silver dressing in group A and 1% silver sulfadiazine dressing in group B. An experienced pediatric surgeon examined the wounds for re epithelialization and efficacy was labeled after 15 days. Out of 264 enrolled patients 148(56.06%) were males and 116(43.94%) were females. Mean age of patients was 3.73±2.34 years. Type of burn was Scald in 215(81.4%) patients and flame in 49(18.6%). Depth of burn was 2nd degree in 185(70.08%) patients and 3rd degree in 79(29.92%) patients. Mean TBSA was 19.93±9.62%. In group A the efficacy was achieved in 91(68.9%) patients whereas in group B the efficacy was achieved in 73(55.3%) patients (p-value<0.05). Hydro-fiber Silver dressing is significantly more efficacious as compared to 1% silver sulfadiazine dressing for treatment of pediatric burn.
Assuntos
Bandagens , Queimaduras , Sulfadiazina de Prata , Humanos , Sulfadiazina de Prata/uso terapêutico , Sulfadiazina de Prata/administração & dosagem , Queimaduras/terapia , Queimaduras/tratamento farmacológico , Feminino , Masculino , Pré-Escolar , Criança , Cicatrização/efeitos dos fármacos , Resultado do Tratamento , Lactente , Anti-Infecciosos Locais/uso terapêutico , Anti-Infecciosos Locais/administração & dosagem , Prata/uso terapêuticoRESUMO
OBJECTIVES: This study aimed to measure the distribution of silver ion (Ag+), mineral recovery, and nanohardness in carious lesions and comprehensively evaluate the degree of dentin restoration. METHODS: Sixty human teeth with root caries were randomly assigned to the control, silver diammine fluoride (SDF) [Safo], and SDF+Glass ionomer cement (GIC) treatment [Safo+Fuji] groups. Micro-computed tomography (micro-CT) was performed at five time points for each sample before/after treatment to evaluate mineral density within and around carious lesions. Three months following treatment, 12 samples were selected for synchrotron radiation X-ray fluorescence analysis to evaluate Ag+ distribution, while 15 samples were selected for nanoindentation. Data were analyzed using Dunnett's T3 test for micro-CT and Wilcoxon rank sum test with Bonferroni correction (p = 0.017) for nanoindentation. The correlation between hardness and mineral change was analyzed using the Spearman rank correlation coefficient. RESULTS: The Safo and Safo+Fuji groups showed significantly higher mineral recovery rates than did the control group (p < 0.001). In the Safo group, Ag+ accumulated in the deeper layers rather than the superficial layer of caries. In the Safo+Fuji group, Ag+ was found evenly distributed throughout caries, with only a few Ag+ detected in the GIC layer. Hardness in the Safo+Fuji group was significantly higher compared with the Safo group at depths in the range of 10-50 µm. CONCLUSION: In the presence of GICs, SDF exhibited high remineralization capacity when diffusing throughout carious lesions over time. Combined treatment with SDF and GIC could strengthen root dentin even in the presence of caries. CLINICAL SIGNIFICANCE: We found that combination treatment with SDF and GIC could increase mineral density in caries and improve the hardness of the tooth structure compared with fluoride-based agents alone. These findings might pave the way for future clinical trials to determine the therapeutic potential of nanotechnology-based restorative materials.
Assuntos
Cariostáticos , Dentina , Cimentos de Ionômeros de Vidro , Dureza , Compostos de Amônio Quaternário , Cárie Radicular , Compostos de Prata , Prata , Microtomografia por Raio-X , Humanos , Cárie Radicular/tratamento farmacológico , Cimentos de Ionômeros de Vidro/química , Cimentos de Ionômeros de Vidro/uso terapêutico , Compostos de Prata/uso terapêutico , Microtomografia por Raio-X/métodos , Dentina/efeitos dos fármacos , Dentina/diagnóstico por imagem , Prata/uso terapêutico , Prata/química , Compostos de Amônio Quaternário/uso terapêutico , Cariostáticos/uso terapêutico , Fluoretos Tópicos/uso terapêutico , Remineralização Dentária/métodos , Restauração Dentária Permanente/métodos , Espectrometria por Raios XRESUMO
AIMS: To assess the impact of various cavity disinfectants PC-PDT (Phycocyanin activated by Photodynamic therapy), PC@AgNPs-PDT (Phycocyanin and silver nanoparticles activated by PDT), and Nd: YAG laser on the survival rate of S.mutans and the bond integrity of composite restoration METHODS: Sixty human mandibular molars that scored 4 and 5 based on ICDAS criteria were included. The infected dentin was removed while the CAD was preserved based on visual, tactile, and staining assessment. S.mutans were cultured on the CAD of twenty samples. All the specimens were indiscriminately distributed into four groups based on cavity disinfection (n=20 each includes n = 5 each group incubated with S.mutans) Group 1: CHX, Group 2: Nd:YAG laser, Group 3: PC-PDT and Group 4: PC@AgNPs-PDT. S.mutans survival rate was assessed for each group(n = 5). Forty samples underwent composite bonding for SBS and failure mode assessment using universal testing machine (UTM) and stereomicroscope. The calculations for the mean and standard deviation (SD) and their comparison among different groups were performed using a one-way analysis of variance (ANOVA) and the Tukey post hoc test (p ≤ 0.05) RESULTS: CAD surface treated disinfected with PC@AgNPs-PDT yielded the lowest survival rates (0.13 ± 0.05 CFU/ml) and highest SBS (17.23 ± 1.45 MPa). Group 1 (CHX) unveiled the highest survival rate of S.mutans (0.33 ± 0.12 CFU/ml). However, Group 2 (Nd:YAG Laser) (11.87 ± 0.67 MPa) presented the lowest SBS CONCLUSION: The combination of Phycocyanin loaded with silver nanoparticles and activated with Photodynamic therapy demonstrates the highest antimicrobial potential and bond strength of composite restorations.
Assuntos
Cárie Dentária , Dentina , Lasers de Estado Sólido , Nanopartículas Metálicas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Ficocianina , Prata , Streptococcus mutans , Fotoquimioterapia/métodos , Prata/farmacologia , Prata/uso terapêutico , Humanos , Streptococcus mutans/efeitos dos fármacos , Nanopartículas Metálicas/uso terapêutico , Ficocianina/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Lasers de Estado Sólido/uso terapêutico , Cárie Dentária/microbiologia , Cárie Dentária/tratamento farmacológico , Dentina/efeitos dos fármacos , Dentina/microbiologia , Desinfecção/métodos , Resistência ao Cisalhamento , Dente MolarRESUMO
The production of nanoparticles enhances the bioactivity of biological molecules for drug delivery to diseased sites. This study explains how silver nanoparticle (AgNP) coating enhanced the protection effects of vanillic acid in male diabetic rats with streptozotocin- (STZ-) induced diabetes. Twenty-four rats were divided into four groups (n = 6) for this investigation. The first group (G1) is untreated, whereas diabetes was induced in the other three groups through STZ injection. Diabetic rats that were not getting therapy were included in the second group (G2, STZ-positive), whereas the other diabetic rats were divided into the third group (G3, vanillic acid-treated) and the fourth group (G4, vanillic acid-coated AgNPs treated). The treatment lasted four weeks. In G2, the induction of diabetes significantly (at P = 0.05) increased in serum glucose, glycated proteins, renal indices, interleukin-6 (IL-6), K+, immunoglobulins, and lipid peroxidation, while decreased Ca++, Na+, and other antioxidants in the kidney tissue homogenate. In addition, pathological altered signs were present in the pancreas and kidneys of diabetic rats. The renal and pancreatic tissues were effectively enhanced by vanillic acid or vanillic acid-coated AgNPs, bringing them very close to their prediabetic conditions. Vanillic acid-coated AgNPs offered a stronger defense against STZ-induced diabetes and lessened the effects of hyperglycemia compared to ordinary vanillic acid. Additionally, using vanillic acid coated with silver nanoparticles greatly increased the antioxidant and antidiabetic activity and reduced inflammation when compared to using vanillic acid alone.
Assuntos
Diabetes Mellitus Experimental , Nanopartículas Metálicas , Ratos , Masculino , Animais , Estreptozocina/farmacologia , Ácido Vanílico/farmacologia , Ácido Vanílico/uso terapêutico , Prata/farmacologia , Prata/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Antioxidantes/uso terapêutico , Estresse OxidativoRESUMO
OBJECTIVE: Activated carbon cloth (ACC), known as Zorflex dressing, has emerged as an innovative approach in managing bacterial infection in diabetic foot ulcer (DFU) treatment. This pilot study was undertaken to determine the efficacy of Zorflex ACC dressing (Chemviron Carbon Cloth Division, UK) compared to standard silver-based dressing on DFUs. METHOD: An open label, comparative, randomised controlled trial enrolling patients who attended the diabetic foot clinic was conducted between August 2022 and August 2023. The primary endpoint was a difference of 20% in wound area reduction with the ACC dressing compared to silver-based dressing within eight weeks. The secondary endpoints were proportion of complete healing, time to healing and adverse events. RESULTS: The cohort comprised 40 patients. The mean wound reduction percentage at 8 weeks for patients in the ACC arm was 85.40±16.00% compared with 65.08±16.36% in the silver-based dressing arm. Complete healing was observed in six of 20 patients in the ACC arm compared to two of 20 in the silver-based dressing arm. CONCLUSION: These data suggest that the ACC dressing promotes better ulcer healing in DFU patients than the silver-based dressing.
Assuntos
Bandagens , Pé Diabético , Cicatrização , Humanos , Pé Diabético/terapia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Projetos Piloto , Prata/uso terapêutico , Carvão Vegetal/uso terapêutico , Carvão Vegetal/administração & dosagemRESUMO
Silver nanoparticle dressings have gained popularity recently as a way to treat challenging wounds. Notwithstanding the properties of Ag-NPS (silver nanoparticles) described by several articles, there is a lack of clinical studies that guide healthcare professionals to specific and conscious use. In this case series, Ag-NPS dressing was tested on a randomized group of 10 patients with complex wounds requiring conservative treatment. Each case was analysed, recording the patient's history, the peculiar characteristics and the progressive changes in the wound. The wound bed and the quality of the peri-wound skin improved and a decrease in signs of infection was observed. The application of the dressing was simple and comfortable for the patient and it was appreciated for its sealing ability. A few capacity restrictions showed up: those should be read as elements to improve the indications for this peculiar dressing. The thin tissue matrix of the Ag-NPS dressing does not allow for massive absorption and also performs poorly in reducing little exudate. The reduction in wound width is also limited: reconstructive surgery was required in half of the enrolled patients to achieve wound healing.
Assuntos
Queimaduras , Nanopartículas Metálicas , Prata , Humanos , Bandagens , Queimaduras/tratamento farmacológico , Nanopartículas Metálicas/uso terapêutico , Prata/uso terapêutico , CicatrizaçãoRESUMO
Introduction: Silver-releasing dressings are used in the treatment of infected wounds. Despite their widespread use, neither the amount of silver released nor the potential in vivo toxicity is known. The aim of this study was to evaluate the cytotoxic effects and the amount of silver released from commercially available dressings with infected wounds. Methods: The review was conducted according to the PRISMA statement. The Web of Science, PubMed, Embase, Scopus, and CINAHL databases were searched for studies from 2002 through December 2022. The criteria were as follows: population (human patients with infected wounds); intervention (commercial dressings with clinical silver authorized for use in humans); and outcomes (concentrations of silver ions released into tissues and plasma). Any study based on silver-free dressings, experimental dressings, or dressings not for clinical use in humans should be excluded. According to the type of study, systematic reviews, experimental, quasi-experimental, and observational studies in English, Spanish, or Portuguese were considered. The quality of the selected studies was assessed using the JBI critical appraisal tools. Studies that assessed at least 65% of the included items were included. Data were extracted independently by two reviewers. Results: 740 articles were found and five were finally selected (all of them quasi-experimental). Heterogeneity was found in terms of study design, application of silver dressings, and methods of assessment, which limited the comparability between studies. Conclusion: In vivo comparative studies of clinical dressings for control of infection lack a standardized methodology that allows observation of all the variables of silver performance at local and systemic levels, as well as evaluation of its cytotoxicity. It cannot be concluded whether the assessed concentrations of released silver in commercial dressings for the topical treatment of infected wounds are cytotoxic to skin cells. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022351041, PROSPERO [CRD42022351041].
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Prata , Infecção dos Ferimentos , Humanos , Bandagens , Bases de Dados Factuais , Íons , Prata/uso terapêutico , Prata/toxicidade , Infecção dos Ferimentos/terapiaRESUMO
Globally, cardiovascular diseases (CVDs) constitute the leading cause of death at the moment. More effective treatments to combat CVDs are urgently required. Recent advances in nanotechnology have opened the door to new avenues for cardiovascular health treatment. Silver nanotechnology's inherent therapeutic powers and wide-ranging applications have made it the center of focus in recent years. This review aims to analyze the chemical, physical, and biological processes ofproducing AgNPs and determine their potential utility as theranostics. Despite significant advances, the precise mechanism by which AgNPs function in numerous biological systems remains a mystery. We hope that at the end of this review, you will better understand how AgNPs affect the cardiovascular system from the research done thus far. This endeavor thoroughly investigates the possible toxicological effects and risks associated with exposure to AgNPs. The findings shed light on novel applications of these versatile nanomaterials and point the way toward future research directions. Due to a shortage of relevant research, we will limit our attention to AgNPs as they pertain to CVDs. Future research can use this opportunity to investigate the many medical uses of AgNPs. Given their global prevalence, we fully endorse academics' efforts to prioritize nanotechnological techniques in pursuing risk factor targeting for cardiovascular diseases. The critical need for innovative solutions to this widespread health problem is underscored by the fact that this technique may help with the early diagnosis and treatment of CVDs.
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Doenças Cardiovasculares , Nanopartículas Metálicas , Prata , Humanos , Prata/uso terapêutico , Fenômenos Fisiológicos Cardiovasculares/efeitos dos fármacos , AnimaisRESUMO
Trichinellosis is a worldwide zoonotic disease. The majority of currently available anti-trichinellosis medications exhibit inadequate efficacy. The efficacy of a natively prepared new formulation of silver nanoparticles (Ag-NPs) was evaluated in the treatment of Trichinella spiralis (T. spiralis) infection in mice alone and combined with multivitamin-mineral (MM). After investigating the product's biological and pharmacological characteristics, its therapeutic dose was estimated to be Ag-NPs at 21.5 mg/kg B.W. This dose was orally inoculated to experimentally infected mice at 3-5 days post-inoculation (dpi) against the mature worms, at 8-10 dpi against the newborn larvae, and at 33-35th dpi against the encapsulated larvae. Each treatment's efficacy was assessed by scarifying control and treated mice 3 days post-treatment. The drug alone or in supplement form has a high trichinocidal effect exceeding that of the reference drug. Early treatment (3-5 dpi) by Ag-NPs or Ag-NPs + MM and albendazole revealed high efficacy against the intestinal stage, reaching 93.3%, 94.7%, and 90.6% for the three treatments, respectively. The materials causing a significant (P-value < 0.001) decrease in the mean encapsulated larvae reached 86.61%, 89.07%, and 88.84%/gm of muscles using the three treatments, respectively. Moreover, all larvae extracted from Ag-NPs-treated groups failed to induce infection post-inoculation in new mice. Additionally, combining the material with MM proved to overcome the reversible adverse effects of silver material on the estimated redox parameters and liver and kidney biomarkers, denoting its ability to alleviate Ag-NP toxicity. In conclusion, the high trichinocidal effect of Ag-NPs against the adult and encapsulated larvae during a short inoculation period introduced Ag-NPs as an alternative to other nematicidal drugs.
Assuntos
Nanopartículas Metálicas , Trichinella spiralis , Triquinelose , Camundongos , Animais , Prata/farmacologia , Prata/uso terapêutico , Albendazol/uso terapêutico , Larva , Vitaminas/uso terapêuticoRESUMO
Pseudomonas aeruginosa (P. aeruginosa), a drug-resistant Gram-negative pathogen, is listed among the "critical" group of pathogens by the World Health Organization urgently needing efficacious antibiotics in the clinics. Nanomaterials especially silver nanoparticles (AgNPs) due to the broad-spectrum antimicrobial activity are tested in antimicrobial therapeutic applications. Pathogens rapidly develop resistance to AgNPs; however, the health threat from antibiotic-resistant pathogens remains challenging. Here we present a strategy to prevent bacterial resistance to silver nanomaterials through imparting chirality to silver nanoclusters (AgNCs). Nonchiral AgNCs with high efficacy against P. aeruginosa causes heritable resistance, as indicated by a 5.4-fold increase in the minimum inhibitory concentration (MIC) after 9 repeated passages. Whole-genome sequencing identifies a Rhs mutation related to the wall of Gram-negative bacteria that possibly causes morphology changes in resistance compared to susceptible P. aeruginosa. Nevertheless, AgNCs with laevorotary chirality (l-AgNCs) induce negligible resistance even after 40 repeated passages and maintain a superior antibacterial efficiency at the MIC. l-AgNCs also show high cytocompatibility; negligible cytotoxicity to mammalian cells including JB6, H460, HEK293, and RAW264.7 is observed even at 30-fold MIC. l-AgNCs thus are examined as an alternative to levofloxacin in vivo, healing wound infections of P. aeruginosa efficaciously. This work provides a potential opportunity to confront the rising threat of antimicrobial resistance by developing chiral nanoclusters.
Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Animais , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Prata/farmacologia , Prata/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Células HEK293 , Pseudomonas aeruginosa , Testes de Sensibilidade Microbiana , MamíferosRESUMO
Medical dressings, as a cover for wounds, can replace damaged skin in the wound healing process to play a temporary barrier role, avoid or control wound infection, and provide a favorable environment for wound healing. Therefore, there is an urgent need for medical antimicrobial dressings for the treatment of chronic wounds. Although traditional polyurethane foam has been widely used in medical dressings, conventional polyurethane foams are primarily prepared using nonbiocompatible isocyanate-based compounds, which are potentially hazardous for both operators and applications in the medical field. Here, we propose nonisocyanate polyurethane foams naturally derived from lignin by enzymatic lignin alkylation, cyclic carbonation modification, and polymerization with diamine and the addition of a blowing agent. Silver nanoparticle solution was added during foaming to confer antimicrobial properties. This lignin-based nonisocyanate polyurethane/silver composite foam (named NIPU foam-silver) using a green synthesis method has good mechanical properties, which can be used to manufacture polyurethane/silver foams, and thermal and antimicrobial properties. Notably, NIPU foam-Ag showed more than 95% bactericidal efficacy against both Escherichia coli and Staphylococcus aureus within 4 h. Evaluation of in vitro wounds in mice showed that this antimicrobial composite foam rapidly promotes wound healing and repairs damaged tissue. This suggests that this biobased biodegradable antimicrobial foam has significant scope for clinical applications in wound management.
Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Animais , Camundongos , Poliuretanos/farmacologia , Lignina/farmacologia , Prata/farmacologia , Prata/uso terapêutico , Anti-Infecciosos/farmacologia , CicatrizaçãoRESUMO
BACKGROUND: Chitosan is known to inhibit the growth of many bacteria and fungi. Tissue conditioners are commonly used to prevent bone destruction under dentures. However, over time, these materials can become a suitable substrate for microbial growth. One approach to improving dental materials is the use of nanoparticles. This study examined the antifungal properties of chitosan and green technique-synthesized silver nanoparticles in combination with tissue conditioners. METHODS: Tissue conditioner materials were mixed with chitosan and silver nanoparticles at concentrations of 0.097%, 0.19%, and 0.37%, along with 1.25 ppm Nystatin, and their antimicrobial properties against Candida albicans were investigated. The growth rate was measured after 24 h of incubation at 37 °C. Non-parametric tests, such as the Kruskal-Wallis H test and Mann-Whitney U test with Bonferroni correction, were used for data analysis after verifying that the groups did not have a normal distribution. RESULTS: Compared with the control and Nystatin groups, the Chitosan-silver groups showed a significant decrease in the number of CFUs of Candida albicans. CONCLUSIONS: The combination of chitosan and silver nanoparticles with tissue conditioner materials is a promising alternative for preventing and treating denture stomatitis. These findings suggest that using very small amounts of nanoparticles in dental materials could effectively prevent microbial growth, which could improve the longevity and efficacy of dental prosthetics and materials.
Assuntos
Anti-Infecciosos , Quitosana , Nanopartículas Metálicas , Estomatite sob Prótese , Humanos , Nistatina/farmacologia , Nistatina/uso terapêutico , Quitosana/farmacologia , Quitosana/uso terapêutico , Prata/farmacologia , Prata/uso terapêutico , Estomatite sob Prótese/tratamento farmacológico , Nanopartículas Metálicas/uso terapêutico , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida albicans , Materiais DentáriosRESUMO
INTRODUCTION: Chemodynamic therapy (CDT) holds great promise in achieving cancer therapy through Fenton and Fenton-like reactions, which generate highly toxic reactive species. However, CDT is limited by the lower amount of catalyst ions that can decompose already existing intracellular H2O2 and produce reactive oxygen species (ROS) to attain a therapeutic outcome. OBJECTIVES: To overcome these limitations, a tailored approach, which utilizes dual metals cations (Ag+, Fe2+) based silver pentacyanonitrosylferrate or silver nitroprusside (AgNP) were developed for Fenton like reactions that can specifically kill cancer cells by taking advantage of tumor acidic environment without used of any external stimuli. METHODS: A simple solution mixing procedure was used to synthesize AgNP as CDT agent. AgNP were structurally and morphologically characterized, and it was observed that a minimal dose of AgNP is required to destroy cancer cells with limited effects on normal cells. Moreover, comprehensive in vitro studies were conducted to evaluate antitumoral mechanism. RESULTS: AgNP have an effective ability to decompose endogenous H2O2 in cells. The decomposed endogenous H2O2 generates several different types of reactive species (â¢OH, O2â¢-) including peroxynitrite (ONOO-) species as apoptotic inducers that kill cancer cells, specifically. Cellular internalization data demonstrated that in short time, AgNP enters in lysosomes, avoid degradation and due to the acidic pH of lysosomes significantly generate high ROS levels. These data are further confirmed by the activation of different oxidative genes. Additionally, we demonstrated the biocompatibility of AgNP on mouse liver and ovarian organoids as an ex vivo model while AgNP showed the therapeutic efficacy on patient derived tumor organoids (PDTO). CONCLUSION: This work demonstrates the therapeutic application of silver nitroprusside as a multiple ROS generator utilizing Fenton like reaction. Thereby, our study exhibits a potential application of CDT against HGSOC (High Grade Serous Ovarian Cancer), a deadly cancer through altering the redox homeostasis.
Assuntos
Neoplasias , Prata , Camundongos , Animais , Humanos , Espécies Reativas de Oxigênio/metabolismo , Prata/química , Prata/farmacologia , Prata/uso terapêutico , Nitroprussiato/farmacologia , Nitroprussiato/uso terapêutico , Ácido Peroxinitroso/uso terapêutico , Peróxido de Hidrogênio/química , Neoplasias/tratamento farmacológicoRESUMO
BACKGROUND: Increased Staphylococcus aureus (SA) colonization is considered an important factor in the pathogenesis of atopic dermatitis (AD). Antibacterial therapeutic clothing aims to reduce SA colonization and AD inflammation; however, its role in the management of AD remains poorly understood. OBJECTIVES: To investigate the effectiveness of antibacterial therapeutic clothing + standard topical treatment in patients with moderate-to-severe AD vs. standard therapeutic clothing + standard topical treatment; and, if effectiveness was demonstrated, to demonstrate its cost-effectiveness. METHODS: A pragmatic double-blinded multicentre randomized controlled trial (NCT04297215) was conducted in patients of all ages with moderate-to-severe AD. Patients were centrally randomized 1 : 1 : 1 to receive standard therapeutic clothing or antibacterial clothing based on chitosan or silver. The primary outcome was the between-group difference in Eczema Area and Severity Index (EASI) measured over 52 weeks. Secondary outcomes included patient-reported outcomes (PROs), topical corticosteroid (TCS) use, SA colonization, safety and cost-effectiveness. Outcomes were assessed by means of (generalized) linear mixed-model analyses. RESULTS: Between 16 March 2020 and 20 December 2021, 171 patients were enrolled. In total, 159 patients were included (54 in the standard therapeutic clothing group, 50 in the chitosan group and 55 in the silver group). Adherence was high [median 7 nights a week wear (interquartile range 3-7)]. Median EASI scores at baseline and at 4, 12, 26 and 52 weeks were 11.8, 4.3, 4.6, 4.2 and 3.6, respectively, in the standard therapeutic clothing group vs. 11.3, 5.0, 3.0, 3.0 and 4.4, respectively, in the chitosan group, and 11.6, 5.0, 5.4, 4.6 and 5.8, respectively, in the silver group. No differences in EASI over 52 weeks between the standard therapeutic clothing group, the chitosan group [-0.1, 95% confidence interval (CI) -0.3 to 0.2; P = 0.53] or the silver group (-0.1, 95% CI -0.3 to 0.2; P = 0.58) were found. However, a small significant group × time interaction effect between the standard and silver groups was found (P = 0.03), in which the silver group performed worse after 26 weeks. No differences between groups were found in PROs, TCS use, SA skin colonization and healthcare utilization. No severe adverse events or silver absorption were observed. CONCLUSIONS: The results of this study suggest no additional benefits of antibacterial agents in therapeutic clothing in patients with moderate-to-severe AD.
Assuntos
Quitosana , Dermatite Atópica , Fármacos Dermatológicos , Infecções Estafilocócicas , Humanos , Corticosteroides/uso terapêutico , Antibacterianos/efeitos adversos , Quitosana/uso terapêutico , Vestuário , Dermatite Atópica/tratamento farmacológico , Fármacos Dermatológicos/uso terapêutico , Método Duplo-Cego , Glucocorticoides/uso terapêutico , Índice de Gravidade de Doença , Prata/uso terapêutico , Resultado do TratamentoRESUMO
Microbial biofilms are a major hindrance in the wound healing process, prolonging the inflammatory response phase, thus making them a target in treatment. The aim of this study is to assess the antibacterial properties of commercially available wound dressings, of various material composition and antibacterial agents, towards multiple in vitro microbial and biofilm models. A variety of in vitro microbial and biofilm models were utilised to evaluate the ability of wound dressing materials to sequester microbes, prevent dissemination and manage bioburden. Sequestering and dissemination models were used to evaluate the ability of wound dressing materials to prevent the biofilm-forming bacterium, Pseudomonas aeruginosa, from migrating through dressing materials over a 24-72 h challenge period. Additionally, Centre for Disease Control (CDC) Bioreactor and Drip Flow models were used to evaluate antibacterial killing efficacy towards established P. aeruginosa and Staphylococcus aureus biofilms using more challenging, wound-like models. Controlled-release iodine foam and silver-impregnated carboxymethylcellulose (CMC) wound dressing materials demonstrated potent biofilm management properties in comparison to a methylene blue and gentian violet-containing foam dressing. Both the iodine-containing foam and silver-impregnated CMC materials effectively prevented viable P. aeruginosa dissemination for up to 72 h. In addition, the controlled-release iodine foam and silver-impregnated CMC materials reduced P. aeruginosa bioburden in the Drip Flow model. The controlled-release iodine foam demonstrated superiority in the CDC Bioreactor model, as both the silver- and iodine-containing materials reduced S. aureus to the limit of detection, but P. aeruginosa growth was only completely reduced by controlled-release iodine foam dressing materials. The data generated within the in vitro biofilm models supports the clinical data available in the public domain for the implementation of iodine foam dressings for effective biofilm management and control in wound care.
Assuntos
Iodo , Infecção dos Ferimentos , Humanos , Staphylococcus aureus , Prata/uso terapêutico , Iodo/farmacologia , Iodo/uso terapêutico , Preparações de Ação Retardada/uso terapêutico , Bandagens , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Cicatrização , Biofilmes , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/prevenção & controle , Pseudomonas aeruginosa/fisiologiaRESUMO
BACKGROUND: Silver nanoparticle was developed to overcome the drawback of silver diamine fluoride. However, evidence is limited, especially in root caries. The aim of this study was to evaluate the remineralization effect of silver nanoparticles on root caries. MATERIALS AND METHODS: Fifty-five root human dentin slices size 5 × 5 mm2 from patients aged over 60 years old were immersed in demineralized solution to create artificial caries. Specimens were allocated into five groups according to the remineralizing agents: silver diamine fluoride (SDF), silver nanoparticles solution (AgNPs), silver nanoparticle solution followed by sodium fluoride varnish (AgNPs+NaF), sodium fluoride varnish (NaF), and tap water. After 8 days of pH-cycling challenge, the microhardness test, lesion depth evaluation, dentin surface morphology, and elemental analysis were performed. Data was analysed using F-test One-way ANOVA followed by Tukey's post hoc test and paired T-test. RESULTS: All test groups demonstrated a significantly higher microhardness value and lower lesion depth compared with the control group. AgNPs+NaF and NaF-treated groups showed lower efficacy than SDF. Crystal precipitation was presented in all groups composed of silver. CONCLUSION: Addition of fluoride varnish did not benefit for silver nanoparticles in preventing further demineralization. SDF provides the highest effectiveness in elderly root carious dentin.