Prevention Of Bacterial Infections Research Articles

Hepcidin agonists grape seed proanthocyanidins and berberine hydrochloride improve immunity and prevention against bacterial infection in grass carp (Ctenopharyngodon idella)

Hepcidin is an antimicrobial peptide and iron-regulating factor that has been shown to play a crucial role in combating bacterial diseases, making it a viable alternative to antibiotics. However, its widespread application is limited due to its susceptibility to degradation in vivo and high production costs. Certain extracts from traditional Chinese medicinal plants exhibit significant potential in treating iron overload conditions. This study aims to identify an effective and practical herbal agent as a hepcidin agonist. The results indicated that grape seed proanthocyanidins (GSP) and berberine hydrochloride (BBR) significantly upregulate the expression levels of hepcidin and ferritin genes in L8824 cells. Additionally, both compounds exhibited excellent in vitro antibacterial activity. Interestingly, the combined application of these two substances yields unexpectedly favorable results. Oral administration of GSP + BBR effectively promoted growth in grass carp, enhanced survival rates, and significantly increased serum innate immunity indicators. Furthermore, it reduced bacterial loads in the head kidney, spleen, hepatopancreas, and intestinal of grass carp following infection. Additionally, it elevated the expression levels of immune genes IL-1β, IL-6, and TNF-α in the head kidney after infection, and markedly alleviated pathological damage in intestinal tissues. These results demonstrated that GSP and BBR act as hepcidin agonists to enhance the expression of endogenous hepcidin, providing a novel approach for the prevention of bacterial infections in aquaculture.

Three hepcidins from the spotted knifejaw (Oplegnathus punctatus) promote antimicrobial activity via TLR/NFκB pathway

Hepcidin belongs to a class of small cationic antimicrobial peptides rich in cysteine. It is synthesized by liver and is widely involved in host antimicrobial, antiviral and other immune responses. We identified and characterized three hepcidin genes (OpHep1, OpHep2 and OpHep3) in spotted knifejaw. All the OpHeps shared high identities with hepcidins in other teleost, containing alpha helix and β-sheets. Three OpHeps were all detected in healthy tissues, with the abundant expression in liver. They were significantly increased after Vibrio harveyi infection in the six immune-relevant tissues (liver, kidney, spleen, gill, skin and intestine). OpHeps knockdown in spotted knifejaw liver cells affected the mRNA levels of inflammation-related genes, including il1β, il6, il8, and nfκb. Further, the recombinant hepcidin proteins were effective in suppressing the growth of both Gram-negative and Gram-positive bacteria. To identify the function of OpHeps in vivo, we performed the overexpression of three OpHeps in zebrafish, and found OpHeps could significantly induce immune-related genes expression in transgenic zebrafish, including myd88, il10, il21, il16, tlr1, tlr3 and lysozyme. When infected with V. harveyi, OpHeps transgenic zebrafishes had a higher survival rate than wild-type zebrafishes. The expression of myd88, il10, il8, il1β, nfκb and lysozyme were all significantly up-regulated in transgenic fishes during bacterial infection. In summary, these results indicated that hepcidin could protect fish fight against pathogen through TLR/NFκB signaling cascade and Lysozyme. Three OpHeps would be potential targets for prevention of bacterial infections in aquaculture industry of spotted knifejaw, which provided a new idea for the molecular breeding of fish disease resistance.

Management of Necrotic Transmetatarsal Amputation with <i>Argania</i> Honey Dressing: A Case Report

Chronic wounds represent a significant global health concern, accounting for a considerable proportion of amputations. Recent advances in healthcare have highlighted the importance of effective wound healing and the prevention of bacterial infections, as these factors are crucial contributors to elevated morbidity rates. Selecting an appropriate wound dressing has presented a significant challenge for healthcare professionals, particularly in developing countries. Honey, a traditional remedy with a long history of use, has been employed in wound care for centuries. This report presents a case study of effective management in a 74-year-old patient with a 28-year history of type II diabetes. This individual experienced a complication related to diabetic foot issues, necessitating toe amputation. This procedure subsequently resulted in difficulties involving necrosis. The treatment protocol included the application of a dressing based on pure Argania honey (Argania spinosa, an endemic tree of southwestern Morocco), without additives, pasteurisation or manipulation. A sharp debridement procedure was previously performed to facilitate the impregnation of honey in the affected area of necrosis. At the end of the treatment all symptoms, including pain, exudates, odour, burning sensation and itching, were fully alleviated. Moreover, a considerable decrease in swelling and wound size was evident, suggesting significant healing in the injured area. The administration of natural remedies for the treatment of this kind of injury may prove an efficacious strategy for the enhancement of quality of life for diabetic patients.

Studying the application of a microbiological complex in sterbel growing

Abstract The main goal of the research is to establish the effect of the Bonaka-APK microbiological complex, which is a metabiotic for the management of fish autoflora and the comprehensive prevention of bacterial infections for fingerling sturgeon (sterbel). To achieve the goal, the following tasks were set: to establish the effect of Bonac-APK on fingerling sturgeon; establish the economic efficiency of its use for aquaculture. The study of the effect of the additive for growing aquaculture for yearling sturgeon fish (sterbel) was carried out with a fish weight of 130 g. The study showed that in an experiment on Sterbel the weight of fish at the end of rearing increased in experimental groups by 3.5-15.6%. The body length of fish in experimental groups increased by 1.1-2.2%. The survival rate of fish in all groups was 100%. Biochemical blood parameters of fish were within normal limits in both the control and experimental groups, which indicates that the probiotic feed additive Bonaka-APK does not have a harmful effect on the fish body. The level of lipid peroxidation increased, which indicates an increase in the antioxidant defense of the Sterbel body. The decrease in feed costs per 1 kg of weight gain compared to the control was 8.0-12.0% in experimental groups. It is recommended to use the microbiological complex Bonaka-APK in an amount of 0.4% by weight of the feed, which is a metabiotic for managing fish autoflora and complex prevention of bacterial infections for sturgeon fingerlings of the BONAKA Company.

NIR-driven intense UV upconversion films for non-contact high-efficiency prevention of bacterial infections

Bacterial infections on wounds imposes a significant limitation to the wound healing. Although the conventional drug antibacterial dressing is employed for hindering bacterial infection, the inevitable microbial resistance and secondary damage severely limit the quality and speed of wound healing. Herein, the NIR-driven intense UV upconversion (UC) BaLu2F8:80%Yb3+/0.5%Tm3+ microcrystals are, for the first time, designed and fabricated into solid sterilization film to protect the wounds from infections. Equipped with excessive Yb3+ sensitizers, the emission of Yb3+/Tm3+ co-doped monoclinic BaLu2F8 matrix achieve a 175-fold enhancement at the UV band. The UV UC microcrystals was further fabricated into a NIR-to-UV sterilization film with a diameter of 1.5 cm and a thickness of 150 μm using solution casting method, which can efficiently destroy 97 % of E. coli with a NIR irradiation of 5 minutes. Due to the outstanding penetrability of NIR irradiation, the sterilization film under 4 layers gauze dressing can be activated to produce UV photons. The in-vivo mouse tests demonstrate the well-designed NIR-to-UV sterilization film can speed up the wound healing by high-efficient inhibiting E. coli infection under the irradiation of 980 nm NIR laser. The non-contact NIR-driven UV sterilization film require no more drugs and dressing exchange, thus entirely eliminating the effect of microbial resistance and secondary damage from conventional drug dressing. Our work provides a new alternative for constructing highly-efficiency sterilization dressing through the utilization of NIR-to-UV optical conversion materials.

Casein phosphopeptide/antimicrobial peptide co-modified SrTiO3 nanotubes for prevention of bacterial infections and repair of bone defects

Endowing titanium surfaces with multifunctional properties can reduce implant-related infections and enhance osseointegration. In this study, titanium dioxide nanotubes with strontium doping (STN) were first created on the titanium surface using anodic oxidation and hydrothermal synthesis techniques. Next, casein phosphopeptide (CCP) and an antimicrobial peptide (HHC36) were loaded into the STN with the aid of vacuum physical adsorption (STN-CP-H), giving the titanium surface a dual function of "antimicrobial-osteogenic". The surface of STN-CP-H has a suitable roughness and good hydrophilicity, which is conducive to osteoblasts. STN-CP-H had a 99 % antibacterial rate against S. aureus and E. coli and effectively prevented the growth of bacterial biofilm. Meanwhile, the antibacterial mechanism of STN-CP-H was initially explored with the help of transcriptome sequencing technology. STN-CP-H could greatly increase osteoblast adhesion, proliferation, and expression of osteogenic markers (alkaline phosphatase, runt-related transcription) when CCP and Sr worked together synergistically. In vivo, the STN-CP-H coating could effectively promote new osteogenesis around titanium implant bone and had no toxic effects on heart, liver, spleen, lung and kidney tissues. A potential anti-infection bone healing material, STN-CP-H bifunctional coating developed in this work efficiently inhibited bacterial infection of titanium implants and encouraged early osseointegration.

Изучение эффективности использования кормовой добавки «Файбрамакс Плюс» в рационе стербела

A study of the feed additive “Faybramax Plus”, which is a metabiotic for the management of fish autoflora and comprehensive prevention of bacterial infections, was conducted on sterbel yearlings with an initial weight of 130 g. The experience takes place in swimming pools. The water supply in the pools was carried out from a well. The conditions of detention corresponded to the technology of fish farming. The duration of the experiment was 60 days. The number of fish in the group was 150. The control group 1 received a full-fledged combo feed; group 2 was given a full-fledged compound feed + 0.3% of the feed additive “Faybramax Plus”; Group 3 consumed full-fledged compound feed + 0.6% of the feed additive “Faybramax Plus”; group 4 was fed full-fledged compound feed + 1.0% of the feed additive “Faybramax Plus”. It was found that when using the studied feed additive, the live weight of fish in the experimental groups increased by 1.9–6.0% at the end of cultivation. The protein content in the body of sterbel was higher compared to the control by 1.8–7.5%. The cost of the resulting products (increase) compared with the control, it decreased by 4.87–13.78% per group. Profit when using the feed additive “Faybramax Plus” increased by 345.11–1,068.23 rubles per group. The level of profitability increased by 2.71–7.66% per group compared to the control. As a result of the conducted research, it was found that the use of the feed additive “Faybramax Plus” produced by the company SYMBIO is most effective in a percentage ratio of 0.6% by weight of feed, as a result of which the level of profitability increases by 7.66%.

Metagenomic profiling uncovers microbiota and antibiotic resistance patterns across human, chicken, pig fecal, and soil environments

The ongoing and progressive evolution of antibiotic resistance presents escalating challenges for the clinical management and prevention of bacterial infections. Understanding the makeup of resistance genomes and accurately quantifying the current abundance of antibiotic resistance genes (ARGs) are crucial for assessing the threat of antimicrobial resistance (AMR) to public health. This comprehensive study investigated the distribution and diversity of bacterial community composition, ARGs, and virulence factors (VFs) across human, chicken, pig fecal, and soil microbiomes in various provinces of China. As a result, multidrug resistance was identified across all samples. Core ARGs primarily related to multidrug, MLS (Macrolides-Lincosamide-Streptogramins), and tetracycline resistance were characterized. A significant correlation between ARGs and bacterial taxa was observed, especially in soil samples. Probiotic strains such as Lactobacillus harbored ARGs, potentially contributing to the dissemination of antibiotic resistance. We screened subsets of ARGs from samples from different sources as indicators to assess the level of ARGs contamination in samples, with high accuracy. These results underline the complex relationship between microbial communities, resistance mechanisms, and environmental factors, emphasizing the importance of continued research and monitoring to better understand these dynamics.

The synergic effect of nanosecond fiber laser and drug-loaded electrospun PVA coating on metallurgical and biological characteristics of Ti-6Al-4 V alloy

Nowadays, titanium-based implants are widely used to replace damaged or missing body organs. Poor chemical bonding with the bone and infection caused by formation of biofilm on the implant surface are the most common problems with them. So, antibacterial properties and osteoblast adhesion improvement have been intended to address these issues. The aim of this research is cell adhesion improvement and prevention of bacterial infection using surface roughness and in-situ antibiotic drug release. Here, micromachining (nanoseconds) laser with a groove distance of 10, 30, and 50 µm, was used to surface modification. X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), hardness, roughness, and wettability tests were used for physical and metallurgical characterization of surface-modified samples to find the optimum laser processing conditions. Roughness has increased as a result of laser surface modification and surface characteristics of alloy exhibit sensitivity to the groove distance. The lower groove distance indicated the higher roughness and wettability. Martensite phase, α phase, and, Ti3Al were observed in the fusion zone. Also, the dissolution of the beta phase has occurred in the fusion and the heat-affected zones. No oxidation was observed. All these occurred without any change in bulk. Then optimized sample surfaces were coated by the vancomycin-loaded polyvinyl alcohol solution using electrospinning process, and toxicity, cell adhesion, and drug release rate were evaluated. The results showed laser surface modification and coating did not hurt cell viability. Modified samples demonstrated high cell adhesion and improvement in drug release compared to the unmodified samples. The drug release rate was extended from 4 h to 25 h for modified samples. So, the modified implants could indicate a sustained release of antibiotics as well.

Oral Vaccines for Prevention of Bacterial Infections: Development Strategies and Prospects

Oral Vaccines for Prevention of Bacterial Infections: Development Strategies and Prospects

Multi-dynamic-bond cross-linked antibacterial and adhesive hydrogel based on boronated chitosan derivative and loaded with peptides from Periplaneta americana with on-demand removability

The design and development of a bio-adhesive hydrogel with on-demand removability and excellent antibacterial activities are meaningful to achieve high wound closure effectiveness and post-wound-closure care, which is desirable in clinical applications. In this work, a series of adhesive antioxidant antibacterial hydrogels containing peptides from Periplaneta americana (PAP) were prepared through multi-dynamic-bond cross-linking among 3,4-dihydroxybenzaldehyde (DBA) containing catechol and aldehyde groups and chitosan grafted with 3-carboxy-4-fluorophenylboronic acid (CS-FPBA) to enable the effective adhesion of skin tissues and prevention of bacterial infection of wound. PAP was derived from alcohol-extracted residues generated during the pharmaceutical process, aiming to minimize resource wastage and achieve the high-value development of such a medicinal insect. The hydrogel was prepared by freezing-thawing with no toxic crosslinkers. The multi-dynamic-bond cross-linking of dynamic borate ester bonds and dynamic Schiff base bonds can achieve reversible breakage and re-formation and the adhesive strength of CS-FPBA-DBA-P-gel treated with a 20 % glucose solution dramatically decreased from 3.79 kPa to 0.35 kPa within 10 s. Additionally, the newly developed hydrogel presents ideal biocompatibility, hemostasis and antibacterial activity against Staphylococcus aureus and Escherichia coli compared to commercial chitosan gel (approximately 50 % higher inhibition rate), demonstrating its great potential in dealing with infected full-thickness skin wounds.

A New Capillary-Channel Agarose Sponge Assembled with Deep Eutectic Solvent Based Magnetic Fluid for Rapid Hemostasis and Prevention of Bacterial Infection.

A new composite sponge assisted by magnetic field-mediated guidance was developed for effective hemostasis. It was based on polydopamine capillary-channel agarose (PDA-CAGA) sponge as matrix; meanwhile, the combination of deep eutectic solvent (DES, choline chloride:glycerol = 1:1, M/M)-dispersed Fe3O4 nanoparticles after fabrication by tannic acid (DES-Fe3O4@TA) was applied as hemostatic magnetic fluid. This sponge had oriented and aligned capillary channels realized by a 3D printed pattern, which endowed them with obvious shape memory and liquid absorption performance. Computational simulation was performed to describe the fluid status in channels; DES-Fe3O4@TA exhibited good magnetic properties, fluidity, and stability. In addition, the sponge driven to react rapidly with the bleeding site under the effect of a magnetic field presented a shorter hemostasis time (reduced by 85.02% in the tail and 81.07% in the liver of rats) and less blood loss (reduced by 97.08% in the tail and 91.50% in the liver) than those of medical gelatin sponge (GS). Meanwhile, the multifunctional material also exhibited better biocompatibility, procoagulant performance, and significant inhibition on S. aureus and E. coli than GS. As a whole, this work proposed a new strategy for rapid hemostasis by designing a magnetic field assisted composite bacteriostatic material, which also expanded the applications of green solvents in the clinical management field.

The Preventive Effect of Levofloxacin Combined with G-CSF or Only G-CSF Supportive Therapy on Infection in Autologous Hematopoietic Stem Cell Transplantation

To investigate the role of levofloxacin combined with recombinant human granulocyte colony-stimulating factor (G-CSF) or only G-CSF supportive therapy in preventing infection in autologous hematopoietic stem cell transplantation(ASCT), and to analyze the length of hospital stay, hospitalization cost and post-transplant survival of the patients. A retrospective analysis was performed in the patients with hematological malignancies who accepted ASCT at our hospital from January 2012 to July 2022, the febrile neutropenia, the incidence of bacterial infection and the use rate of intravenous antibiotics in the levofloxacin+G-CSF group and only G-CSF support group during ASCT were observed. The length of hospital stay, total cost during hospitalization and survival after 90 days of transplantation between the two groups were compared. A total of 102 cases were included in this study, including 57 cases of multiple myeloma, 36 cases of acute leukaemia, 7 cases of lymphoma, 3 cases of myelodysplastic syndrome, 1 case of light chain amyloidosis, and 1 case of POEMS syndrome. 47 patients received levofloxacin+ G-CSF antibacterial prophylaxis, and 55 patients received G-CSF supportive therapy. In the levofloxacin+ G-CSF group, 40 cases (85.11%) developed febrile neutropenia, and 13 cases (27.66%) were confirmed as bacterial infection. In the G-CSF group, 44 cases (80.00%) developed febrile neutropenia, and 16 cases (29.09%) were bacterial infection. There was no statistically significant difference in the incidence of febrile neutropenia and bacterial infection between the two groups (χ2=0.46，P =0.50; χ2=0.03，P =0.87). The use rate of intravenous antibiotics in the levofloxacin+ G-CSF group was 85.11% (40/47), which was not statistically different from 85.45% (47/55) in the G-CSF group (χ2=0.04，P =0.84). The detection rates of levofloxacin-resistant bacteria in the levofloxacin+ G-CSF group and G-CSF group were 8.57% (3/35) and 21.43% (6/28), respectively, with no statistical difference (χ2=0.65, P >0.05). The median length and median cost of hospitalization in the levofloxacin+ G-CSF group and G-CSF group were 25 d vs 22 d and 78 216.24 yuan vs 80 724.38 yuan, with no statistically significant differences ( t =3.00，P =0.09; t =0.94，P =0.09). Within 90 days after transplantation, two cases (4.26%) died in the levofloxacin+ G-CSF group and one case (1.82%) died in the G-CSF group, with no statistically significant difference between the two groups (χ2=0.53，P =0.47). Application of levofloxacin+ G-CSF showed no significant benefit compared to G-CSF support for the prevention of bacterial infections during ASCT.

Green Synthesis and Characterization of Ginger-Derived Silver Nanoparticles and Evaluation of Their Antioxidant, Antibacterial, and Anticancer Activities.

The efficacy, targeting ability, and biocompatibility of plant-based nanoparticles can be exploited in fields such as agriculture and medicine. This study highlights the use of plant-based ginger nanoparticles as an effective and promising strategy against cancer and for the treatment and prevention of bacterial infections and related disorders. Ginger is a well-known spice with significant medicinal value due to its phytochemical constituents including gingerols, shogaols, zingerones, and paradols. The silver nanoparticles (AgNPs) derived from ginger extracts could be an important non-toxic and eco-friendly nanomaterial for widespread use in medicine. In this study, AgNPs were biosynthesized using an ethanolic extract of ginger rhizome and their phytochemical, antioxidant, antibacterial, and cytotoxic properties were evaluated. UV-visible spectral analysis confirmed the formation of spherical AgNPs. FTIR analysis revealed that the NPs were associated with various functional biomolecules that were associated with the NPs during stabilization. The particle size and SEM analyses revealed that the AgNPs were in the size range of 80-100 nm, with a polydispersity index (PDI) of 0.510, and a zeta potential of -17.1 mV. The purity and crystalline nature of the AgNPs were confirmed by X-ray diffraction analysis. The simple and repeatable phyto-fabrication method reported here may be used for scaling up for large-scale production of ginger-derived NPs. A phytochemical analysis of the ginger extract revealed the presence of alkaloids, glycosides, flavonoids, phenolics, tannins, saponins, and terpenoids, which can serve as active biocatalysts and natural stabilizers of metallic NPs. The ginger extracts at low concentrations demonstrated promising cytotoxicity against Vero cell lines with a 50% reduction in cell viability at 0.6-6 μg/mL. When evaluated for biological activity, the AgNPs exhibited significant antioxidant and antibacterial activity on several Gram-positive and Gram-negative bacterial species, including Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Staphylococcus aureus. This suggests that the AgNPs may be used against multi-drug-resistant bacteria. Ginger-derived AgNPs have a considerable potential for use in the development of broad-spectrum antimicrobial and anticancer medications, and an optimistic perspective for their use in medicine and pharmaceutical industry.

Design, optimization and pharmaceutical characterization of wound healing film dressings with chloramphenicol and ibuprofen

Objective The aim of the present study was to develop and optimize a wound dressing film loaded with chloramphenicol (CAM) and ibuprofen (IBU) using a Quality by Design (QbD) approach. Significance The two drugs have been combined in the same dressing as they address two critical aspects of the wound healing process, namely prevention of bacterial infection and reduction of inflammation and pain related to injury. Methods Three critical formulation variables were identified, namely the ratios of Kollicoat SR 30D, polyethylene glycol 400 and polyvinyl alcohol. These variables were further considered as factors of an experimental design, and 17 formulations loaded with CAM and IBU were prepared via solvent casting. The films were characterized in terms of dimensions, mechanical properties and bioadhesion. Additionally, the optimal formulation was characterized regarding tensile properties, swelling behavior, water vapor transmission rate, surface morphology, thermal behavior, goniometry, in vitro drug release, cell viability, and antibacterial activity. Results The film was optimized by setting minimal values for the folding endurance, adhesive force and hardness. The optimally formulated film showed good fluid handling properties in terms of swelling behavior and water vapor transmission rate. IBU and CAM were released from the film up to 80.9% and 82.5% for 8 h. The film was nontoxic, and the antibacterial activity was prominent against Micrococcus spp. and Streptococcus pyogenes. Conclusions The QbD approach was successfully implemented to develop and optimize a novel film dressing promising for the treatment of low-exuding acute wounds prone to infection and inflammation.

Isolation of cultures of microorganisms from pathological material from cows

Rapidly developing antibiotic resistance limits the capabilities of veterinary specialists and doctors in the fight against infectious diseases. Effective diagnosis and continuous improvement in the field of antimicrobial therapy is the main approach in the treatment and prevention of bacterial infections. According to available data, bacteria are able to develop resistance in 2-3 years, while it takes an average of 5 years to develop and test a new antimicrobial drug. In our study, bacteriological examination of samples of pathological material from cows from 10 livestock farms in different districts of the Leningrad region was carried out, followed by determination of the sensitivity of isolated crops to antibiotics. In this study, 84 samples from cows were selected and examined and 115 cultures of microorganisms were isolated. As a result of the bacteriological study of the pathological material from cows, 9 groups and types of pathogenic and opportunistic microorganisms were identified. The main proportion is detected on staphylococci – 35.7%, mainly Staphylococcus aureus, epidermal staphylococcus and citrus staphylococcus. Escherichia coli (23.5%) and Proteus vulgaris (20.9%) were among the microorganisms in terms of frequency of occurrence. Most of the isolated cultures had average sensitivity to gentamicin, enrofloxacin, ciprofloxacin, ceftriaxone, cefepim, cefotaxime, neomecin; resistant to doxycycline, amoxicillin, levofloxacin, colistin, doxycycline, streptomycin, tylosin, tetracycline.

Comparison of antimicrobial properties of inorganic peroxide polymer composites

AbstractWound healing and prevention of bacterial infections are critical aspects of modern medical care. In this work, antibacterial films were produced by creating composites of polycaprolactone with inorganic peroxides. Calcium, magnesium, and zinc peroxide were incorporated in a biocompatible polymeric film. Iron oxide, sodium bicarbonate, and calcium phosphate were added to reduce hydrogen peroxide and to maintain pH in a less alkaline range, allowing for optimization of the material's antibacterial efficacy while minimizing cytotoxicity toward human fibroblasts. Experiments with common wound pathogens, Staphylococcus aureus and Pseudomonas aerugonisa, confirmed significant and prolonged antibacterial effects of peroxide‐doped films. Findings showed that the addition of CaO2 and MgO2 within the film increased cytotoxicity toward human fibroblasts after 48 h (30%–40% decrease compared to control), whereas ZnO2‐based films exhibited a minimal cytotoxicity consistently maintaining over 70% cell viability throughout the course of the experiment. We examined the materials’ sustained release of reactive oxygen species and oxygen, and pH variation correlated with antibacterial activity. Given the unique combination of antibacterial efficacy and mammalian biocompatibility, these peroxides have value as components to sustain hydrogen peroxide release when appropriately compounded to reduce pH variation and avoid excessive hydrogen peroxide levels.

TiO2/Polystyrene Nanocomposite Antibacterial Material as a Hemoperfusion Adsorbent for Efficient Bilirubin Removal and Prevention of Bacterial Infection.

The use of hemoperfusion adsorbents for the removal of bilirubin in patients with liver failure has become a critical treatment. However, the insufficient clearance of bilirubin and the possibility of bacterial infection during hemoperfusion limit the application. In this work, we designed a novel antibacterial bilirubin adsorbent (PSVT) through the suspension polymerization reaction between double-bond functionalized TiO2 nanoparticles and styrene. PSVT showed an excellent bilirubin adsorption ability and antibacterial performance, ensuring efficient clearance of bilirubin in liver failure patients during hemoperfusion and preventing bacterial infection. The experimental results indicated that TiO2 was uniformly dispersed in the microspheres, which improved the mesoporous structure and increased the specific surface area. Composite adsorbent PSVT showed an exceptional bilirubin adsorption capacity, with the maximum adsorption capacity reaching 24.3 mg/g. In addition, the introduction of TiO2 endowed PSVT with excellent antibacterial ability; the ultimate antibacterial rates against Escherichia coli and Staphylococcus aureus reached 97.31 and 96.47%, respectively. In summary, PSVT served as a novel antibacterial bilirubin adsorbent with excellent bilirubin clearance capacity and antibacterial performance, providing excellent application prospects for treating liver failure patients.

Research Progress on Strategies for Improving the Enzyme Properties of Bacteriophage Endolysins.

Bacterial resistance to commonly used antibiotics is one of the major challenges to be solved today. Bacteriophage endolysins (Lysins) have become a hot research topic as a new class of antibacterial agents. They have promising applications in bacterial infection prevention and control in multiple fields, such as livestock and poultry farming, food safety, clinical medicine and pathogen detection. However, many phage endolysins display low bactericidal activities, short half-life and narrow lytic spectrums. Therefore, some methods have been used to improve the enzyme properties (bactericidal activity, lysis spectrum, stability and targeting the substrate, etc) of bacteriophage endolysins, including deletion or addition of domains, DNA mutagenesis, chimerization of domains, fusion to the membrane-penetrating peptides, fusion with domains targeting outer membrane transport systems, encapsulation, the usage of outer membrane permeabilizers. In this review, research progress on the strategies for improving their enzyme properties are systematically presented, with a view to provide references for the development of lysins with excellent performances.

Berberine-styrene-co-maleic acid nanomicelles: unlocking opportunities for the treatment and prevention of bacterial infections.

The global spread of multi-drug-resistant (MDR) bacteria is rapidly increasing due to antibiotic overuse, posing a major public health threat and causing millions of deaths annually. The present study explored the potential of nanocarriers for delivering novel and alternative antibacterial agents using nanotechnology-based approaches to address the challenge of MDR bacteria. The purpose was to enhance the solubility, stability, and targeted delivery of berberine (BER) and its synthetic derivative NR16 using Styrene-co-Maleic Acid (SMA) nanoparticles. Characterization of the nanoparticles, including dynamic light scattering (DLS) analysis, TEM, and UV/Vis absorption spectroscopy, confirmed their suitability and high stability for passive drug delivery. Antibacterial and antifungal activities were evaluated against a panel of pathogens, revealing significant inhibitory effects on Gram-positive strains; particularly BER, SMA-BER, and NR16 were active against MRSA, MSSA, VR, and VS E. faecalis, and S. epidermidis. Additionally, SMA-BER and SMA-NR16 showed promising activity against biofilm formation of S. epidermidis; while the two free drugs contributed to S. epidermidis biofilm disruption activity. Hemolysis tests and in vitro studies on human embryonic kidney cells (HEK-293) confirmed the safety profiles of the nanoparticles and free drugs. Overall, this research highlighted the potential of nanotechnology in developing effective antibacterial agents with reduced toxicity, addressing the growing threat of MDR bacterial infections.