Disposal of the pollutants arising from farming cattle and other livestock threatens the environment and public safety in diverse ways.Herein,we report on the synthesis of engineered biochars using cow dung as raw mat...Disposal of the pollutants arising from farming cattle and other livestock threatens the environment and public safety in diverse ways.Herein,we report on the synthesis of engineered biochars using cow dung as raw material,and investigating these biochars as antibacterial agents for water decontamination.By coating the biochars with N-halamine polymer and loading them with active chlorine (i.e.,Cl+),we were able to regulate them on demand by tuning the polymer coating and bleaching conditions.The obtained N-halamine-modified biochars were found to be extremely potent against Escherichia coli and Staphylococcus aureus.We also investigated the possibility of using these N-halamine-modified biochars for bacterial decontamination in real-world applications.Our findings indicated that a homemade filter column packed with N-halamine-modified biochars removed pathogenic bacteria from mining sewage,dairy sewage,domestic sewage,and artificial seawater.This proposed strategy could indicate a new way for utilizing livestock pollutants to create on-demand decontaminants.展开更多
The efficient adsorption of radioactive iodine(^(129)I and^(131)I)as nuclear waste is of great importance.Polymer nanocomposites consist of metal-organic frameworks(MOFs)developing for various pollutions sorption and ...The efficient adsorption of radioactive iodine(^(129)I and^(131)I)as nuclear waste is of great importance.Polymer nanocomposites consist of metal-organic frameworks(MOFs)developing for various pollutions sorption and separation have attracted much attention.This study reports the fabrication of magnetic polyacrylonitrile(PAN)/zeolitic imidazolate frameworks(ZIF-8)nanocomposites,PAN/ZIF-8(x%)/Fe_(3)O_(4),x=30 and 50,as iodine capture adsorbents.The PAN/ZIF-8(x%)/Fe_(3)O_(4)nanocomposite beads were fabricated via the phase inversion method,and their potential for iodine capture and separation in solution and vapor was investigated through UV-vis and weighing methods,respectively.Also,antibacterial activity of the as-prepared beads was assessed against E.coil and S.aureus.The as-fabricated compounds were studied by various techniques such as Fourier-transform infrared,X-ray diffraction,scanning electron microscope,energy-dispersive X-ray spectroscopy mapping,transmission electron microscope,N_(2)adsorption isotherm,and vibrating sample magnetometer.The iodine capture results showed that the efficiency of nanocomposites is remarkably higher than the pure PAN beads.Additionally,the asprepared nanocomposite adsorbents displayed higher capture capacities for iodine vapor(1524-4345mg·g^(-1))than iodine solution(187-295 mg·g^(-1)).The as-obtained magnetic nanocomposites can be successfully separated from polluted media by simple filtration or an external magnet,regenerated through washing with ethanol,and reused.Fast capturing,high sorption capacity,rapid separation,and good reusability make the PAN/ZIF-8(x%)/Fe_(3)O_(4)nanocomposites highly effective adsorbents for the separation of iodine from wastewater.Additionally,PAN/ZIF-8(50%)/Fe_(3)O_(4)bead can be considered as a potential new antibacterial agent for water and wastewater treatment.展开更多
Remarkable antibacterial activity of BPA analogues especially for tetrabromobi-sphenol A against Staphylococcus aureus 25923(Sa25923)and methicillin-resistant Staphylococcus aureus(MRSA)has been reported in our previo...Remarkable antibacterial activity of BPA analogues especially for tetrabromobi-sphenol A against Staphylococcus aureus 25923(Sa25923)and methicillin-resistant Staphylococcus aureus(MRSA)has been reported in our previous studies.However,the toxic effects of the compounds as environmental contaminants on the endocrine system limited their applications in the field of medicine and health.Given the abuse of antibiotics has led to the emergence of multiple super-resistant bacteria,we considered that structural modifications based on the BPA structure will be available for molecular designing of potential antimicrobial agents without drug resistance.In this study,to further improve the antibacterial activity and reduce the biological toxicity,we performed the computational models to evaluate the binding affinities of BPA analogues to the potential target DltA protein in the biosynthesis of cell wall.A series of synthesized achiral analogues ofα,α,α′-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene(α,α,α′-TEIB)exhibited low minimum inhibitory concentration against Sa25923 and MRSA(2 or 1μg mL−1).Especially,the analogue A4 did not induce the drug-resistant mutants for all tested Gram-positive bacterial strains and exhibited relatively lower cytotoxicity in HepG2 cells.The developed classification model based on the light gradient boosting algorithm showed the superior performances on the internal robustness and generalization ability for the ligand-based virtual screening of bisphenol and polyphenol antimicrobial substances.Collectively,our findings suggest that the molecular structure ofα,α,α′-TEIB is promising as a scaffold,which is expected to achieve a breakthrough in the development of antibiotics which can prevent the invasion of MRSA and other super bacteria.展开更多
Lack of antibacterial properties in resin-based composites (RBCs) is one of the flaws that cause the failure of filling clinically. Several agents have been incorporated to endow RBCs with antibacterial properties. In...Lack of antibacterial properties in resin-based composites (RBCs) is one of the flaws that cause the failure of filling clinically. Several agents have been incorporated to endow RBCs with antibacterial properties. In this review, we summarize the recent antibacterial agents between 2015 and 2020 using keywords of antibacterial or antimicrobial dental resin composites by PubMed databases. The most effective strategies are concerned with polymerizable monomers (50%), followed by filler particles (39%) and leachable agents (11%). A recent modification of the antibacterial agent is either by combining two agents from the same category or mixing agents from different categories in one. More than two methods were used in one study to assess antibacterial efficacy. The most common method was biofilm colony-forming units (CFUs) counting method (40%), followed by live/dead bacteria staining assay of biofilms (25%), metabolic activity assay of biofilms using MTT assay (16%), lactic acid production assay of biofilms (8%), agar diffusion test (8%), and other methods (3%) such as minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC).展开更多
Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is p...Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is proposed to construct copper sulfides-loaded dual-mesoporous silica nanospheres(Cux-Sy@DMSNs)with various crystal phases for reactive oxygen species(ROS)-mediated and photothermal antibacterial application.With the pore confinement of DMSNs,the crystal phases of copper sulfides including CuS,Cu_(9)S_(5)and Cui.96S can be easily controlled by changing the vulcanization temperature.The relationships between the crystal phases and photothermal properties as well as peroxidase-like activity of copper sulfides were systematically investigated.Results show that the obtained CuS@DMSNs exhibited higher photothermal ability with remarkable photothermal conversion efficiency of 36.86%in the second near-infrared region(NIR-II)and better peroxidase-like activity,compared to those of Cu_(9)S_(5)@DMSNs and Cu_(1.96)S@DMSNs.As a result,the in vitro experiments showed the good antibacterial effect against both gram-negative E.coli and gram-positive S.aureus under 1064 nm laser irradiation and the presence of H_(2)O_(2).Besides,the CCK-8 assay indicated that CuS@p-DMSNs have minimal cytotoxicity against normal human umbilical vein endothelial cells at the ranged concentrations.Therefore,the resultant CuS@p-DMSNs could act as a promising antibacterial agent for deep wound bacterial infection treatment.展开更多
Spinal epidural abscess (SEA) is a rare condition, and a delay in its diagnosis causes paralysis. In this study, we report two rare cases of delayed diagnosis of SEA whose conditions improved after a state of complete...Spinal epidural abscess (SEA) is a rare condition, and a delay in its diagnosis causes paralysis. In this study, we report two rare cases of delayed diagnosis of SEA whose conditions improved after a state of complete paralysis. The first case was a 71-year-old diabetic man who received a corticosteroid injection for shoulder pain that caused intensified pain. Thereafter, the patient developed paralysis of both legs in stage IV according to Heusner staging. Subsequently, he was diagnosed with multiple abscesses and sepsis. He was in a poor state of health. Therefore, we treated his epidural abscess conservatively. After a month, his muscle strength had improved to Heusner stage III-A, and he was transferred to another hospital. The second case was a 64-year-old diabetic man who received an epidural corticosteroid injection for lower back pain. However, the pain intensified and was admitted to the hospital for pyelonephritis. He developed paralysis in both of his arms and legs presenting as a Heusner stage IV, caused by a cervical epidural abscess. A laminoplasty was performed and paralysis was improved. However, the patient subsequently developed a left subcortical hemorrhage. He underwent surgery. However, his right hemiplegia persisted, and on Day 21, he was transferred back to the previous hospital with a Heusner III-A. We could improve the patients’ paralysis by cooperating closely with infectious disease specialists and spine surgeons, taking intensive care, applying antibacterial agents appropriately, and operating quickly.展开更多
Antibacterial Ag-agents are intensively applied as broad spectrum, high-stability, high-efficiency and high-safety inorganic antibacterial agents. We have developed a new kind of antibacterial Ag-agent, namely Ag_2-x(...Antibacterial Ag-agents are intensively applied as broad spectrum, high-stability, high-efficiency and high-safety inorganic antibacterial agents. We have developed a new kind of antibacterial Ag-agent, namely Ag_2-x(NH_4)xMo_3O_(10) ·3H_2O nanowires(NWs). Carrying Ag atoms in the lattice and Ag-rich nanoparticles on the surface, the Ag-doped NWs show strong antibacterial effects for a variety of bacteria including E.coli, Staphylococcus aureus, Candida albicans and Aspergil lus niger. By performing systematic comparison experiments, we have proven that the main antibacterial effects are neither resulted from the tiny amount of Ag+ions released from the Ag-doped NWs in aqueous solutions, nor resulted from Ag-rich nanoparticles of fragments of the NWs when they are slowly dissolved in the Martin broth. Instead, the effects are mainly resulted from a contact mechanism, under which, the Ag-doped NWs need to be physically in contact with the bacteria to be eliminated. This is a novel phenomenon observed in the interactions between nanomaterials and live cells, which is worthy of further investigation at the molecular scale. As the Ag-doped NWs are not dissolved in pure water or weak acids, one may find practical antibacterial applications in textile industry and food storage industry for these unique nanomaterials.展开更多
Ultrasmall silver nanoclusters(Ag NCs)with rich surface chemistry and good biocompatibility are promising in antibacterial application,however,further development of Ag NCs for practical settings has been constrained ...Ultrasmall silver nanoclusters(Ag NCs)with rich surface chemistry and good biocompatibility are promising in antibacterial application,however,further development of Ag NCs for practical settings has been constrained by their relatively weak antibacterial activity.Using the nutritionally-rich medium for bacteria(e.g.,Luria-Bertani(LB)medium)to coat active Ag NCs could further improve their antibacterial activity.Here,we provide a delicate design of a highly efficient Ag NCs@ELB antibacterial agent(ELB denotes the extract of LB medium)by anchoring Ag NCs inside the ELB species via light irradiation.The as-designed Ag NCs with bacterium-favored nutrients on the surface can be easily swallowed by the bacteria,boosting the production of the intracellular reactive oxygen species(ROS,about 2-fold of that in the pristine Ag NCs).Subsequently,a higher concentration of ROS generated in Ag NCs@ELB leads to enhanced antibacterial activity,and enables to reduce the colony forming units(CFU)of both gram-positive and gram-negative bacteria with 3–4 orders of magnitude less than that treated with the pristine Ag NCs.In addition,the Ag NCs@ELB also shows good biocompatibility.This study suggests that surface engineering of active species(e.g.,Ag NCs)with nutritionally-rich medium of the bacteria is an efficient way to improve their antibacterial activity.展开更多
We report a rapid method for synthesis of zeolitic imidazolate framework 8(ZIF-8)-decorated graphene oxide(GO)composites(ZGO)with good antibacterial properties.The ZGO composites were synthesized at room temperature w...We report a rapid method for synthesis of zeolitic imidazolate framework 8(ZIF-8)-decorated graphene oxide(GO)composites(ZGO)with good antibacterial properties.The ZGO composites were synthesized at room temperature with low GO to metal salt ratios.The samples were characterized by X-ray diffraction,transmission electron microscopy,Fourier transform infrared spectroscopy,thermal gravimetric analysis,and surface area analysis.The characterization results show that ZIF-8 with a size of approximately 120 nm is successfully decorated on the surface of GO sheets with the host ZIF-8 framework maintained in the synthesized composite,but there is a significant reduction in the Brunauer-Emmett-Teller surface area.The antibacterial activities of the samples against Escherichia coli ATCC 11229 and Staphylococcus aureus ATCC 6538 as model strains of gram-negative and-positive bacteria,respectively,were determined by disc diffusion and minimum inhibitory concentration(MIC)tests.ZGO-1.0(1 wt%of ratio of GO to metal salt)shows the highest antibacterial activity with MIC values required to inhibit bacterial growth of E.coli and S.aureus of 5 times lower than those of pristine ZIF-8.Different antibacterial mechanisms are proposed based on field-emission scanning electron microscope images of the two bacteria after contact with the synthesized composite.Overall,owing to the simple synthesis,good stability,low chemical usage,and excellent antibacterial activity of the ZGO composites,they show great potential for application in the field of microbial contamination control.展开更多
The abuse of antibiotics causes severe bacterial resistance, and the shortage of antibiotics has created a global public health crisis. This situation has prompted people to develop new antibacterial agents independen...The abuse of antibiotics causes severe bacterial resistance, and the shortage of antibiotics has created a global public health crisis. This situation has prompted people to develop new antibacterial agents independent of traditional antibiotics. Here, we created a series of photosensitive azobenzene-quaternary ammonium salt smart antibacterial agents by connecting azobenzene with amines with different chain lengths to improve the antibacterial selectivity of quaternary ammonium salt(QAS) and prevent the accumulation of active QAS in the environment. After trans-cis isomerization, the solubility of the title compound(compound 4) increased and the antibacterial property enhanced. The experimental results suggested that the antibacterial effect of compound 4 was significantly enhanced after 365 nm light irradiation, and it had photosensitive intelligent antibacterial activity and could be reused. Notably, we did not obtain any mutants of Staphylococcus aureus or Escherichia coli resistant to compound 4. In general,compound 4 has the advantages of high yield, photo-controllable antibacterial properties, reusability, and does not induce bacterial resistance. This photosensitive antibacterial compound provides a new idea for the construction of intelligent disinfectants and is expected to be a candidate for disinfectants in public facilities and medical architecture.展开更多
The uniqueness of Zn is that, it is the second most abundant trace element in the animal body but can't be stored in the body, thus regular dietary intake is required. Zinc oxide(ZnO) nanoparticles(NP) particles a...The uniqueness of Zn is that, it is the second most abundant trace element in the animal body but can't be stored in the body, thus regular dietary intake is required. Zinc oxide(ZnO) nanoparticles(NP) particles are being extensively used in paints, skin lotions pigments, food, electronics appliances, biological and pharmaceutical applications and many more. Zinc oxide nanoparticles are the specially prepared mineral salt having particle size of 1 to 100 nm. It promotes growth can act as antibacterial agent,modulates the immunity and reproduction of the animals. Both in lower and higher doses of specifications it has exhibited a variety of effects on animal performances. Apart from being highly bioavailable, reports have already pointed out the growth promoting, antibacterial, immuno-modulatory and many more effects of nano zinc(nZn). These can be used at lower doses and can provide better result than the conventional Zn sources and indirectly prevents environmental contamination also. The toxicological studies provide mixed results in animal models. Studies been undertaken in diversified animal species and encouraging effects have been reported with nZn supplementation. However, there is a need to optimize the dose and duration of ZnO NP supplementation for human and livestock,depending on its biological effects. Actual bioavailability of ZnO NP in livestock is still to be worked out.In this review we have attempted to summarize, conclude the beneficial effects of nZnO and its possible usage as mineral supplement to different categories of human and livestock.展开更多
Introduction Antibiotic use for acute otitis media(AOM)is one of the major sources of antimicrobial resistance.However,the effective minimal antibiotic duration for AOM remains unclear.Moreover,guidelines often recomm...Introduction Antibiotic use for acute otitis media(AOM)is one of the major sources of antimicrobial resistance.However,the effective minimal antibiotic duration for AOM remains unclear.Moreover,guidelines often recommend broad ranges(5-10 days)of antibiotic use,yet the clinical impact of such a wide window has not been assessed.Methods We systematically searched PubMed/MEDLINE,Embase,Scopus,Web of Science,and Cochrane Library from database inception to 6 October 2021.Network meta-analysis was conducted on randomized controlled trials that assessed antibiotic treatment for AOM in children(PROSPERO CRD42020196107).Results For amoxicillin and amoxicillin-clavulanate,7-day regimens were noninferior to 10-day regimens in clinical responses[amoxicillin:risk ratio(RR)0.919(95%CI 0.820-1.031),amoxicillin-clavulanate:RR 1.108(0.957-1.282)],except for≤2 years.For the third-generation cephalosporins,7-day and 10-day regimens had similar clinical responses compared to placebo[7-day:RR 1.420(1.190-1.694),10-day:RR 1.238(1.125-1.362)compared to placebo].However,5-day regimens of amoxicillin-clavulanate and third-generation cephalosporins were inferior to 10-day regimens.Compared to amoxicillin,a shorter treatment duration was tolerable with amoxicillin-clavulanate.Conclusions Our findings indicated that 1O days of antibiotic use may be unnecessarily long,while the treatment duration should be longer than 5 days.Otherwise,5-day regimens would be sufficient for a modest treatment goal.Our findings revealed that the current wide range of recommended antibiotic durations may have influenced the clinical outcome of AOM,and a narrower antibiotic duration window should be re-established.展开更多
基金supported by the National Natural Science Foundation of China(No.51663019)the Natural Science Foundation of the Inner Mongolia Autonomous Region(No.2019JQ03)the Program for National Undergraduate Innovation and Entrepreneurship Training(Nos.201911709005 and 201911709006).
文摘Disposal of the pollutants arising from farming cattle and other livestock threatens the environment and public safety in diverse ways.Herein,we report on the synthesis of engineered biochars using cow dung as raw material,and investigating these biochars as antibacterial agents for water decontamination.By coating the biochars with N-halamine polymer and loading them with active chlorine (i.e.,Cl+),we were able to regulate them on demand by tuning the polymer coating and bleaching conditions.The obtained N-halamine-modified biochars were found to be extremely potent against Escherichia coli and Staphylococcus aureus.We also investigated the possibility of using these N-halamine-modified biochars for bacterial decontamination in real-world applications.Our findings indicated that a homemade filter column packed with N-halamine-modified biochars removed pathogenic bacteria from mining sewage,dairy sewage,domestic sewage,and artificial seawater.This proposed strategy could indicate a new way for utilizing livestock pollutants to create on-demand decontaminants.
基金financial support(SCU.SC1400.29011)from the Shahid Chamran University of Ahvaz。
文摘The efficient adsorption of radioactive iodine(^(129)I and^(131)I)as nuclear waste is of great importance.Polymer nanocomposites consist of metal-organic frameworks(MOFs)developing for various pollutions sorption and separation have attracted much attention.This study reports the fabrication of magnetic polyacrylonitrile(PAN)/zeolitic imidazolate frameworks(ZIF-8)nanocomposites,PAN/ZIF-8(x%)/Fe_(3)O_(4),x=30 and 50,as iodine capture adsorbents.The PAN/ZIF-8(x%)/Fe_(3)O_(4)nanocomposite beads were fabricated via the phase inversion method,and their potential for iodine capture and separation in solution and vapor was investigated through UV-vis and weighing methods,respectively.Also,antibacterial activity of the as-prepared beads was assessed against E.coil and S.aureus.The as-fabricated compounds were studied by various techniques such as Fourier-transform infrared,X-ray diffraction,scanning electron microscope,energy-dispersive X-ray spectroscopy mapping,transmission electron microscope,N_(2)adsorption isotherm,and vibrating sample magnetometer.The iodine capture results showed that the efficiency of nanocomposites is remarkably higher than the pure PAN beads.Additionally,the asprepared nanocomposite adsorbents displayed higher capture capacities for iodine vapor(1524-4345mg·g^(-1))than iodine solution(187-295 mg·g^(-1)).The as-obtained magnetic nanocomposites can be successfully separated from polluted media by simple filtration or an external magnet,regenerated through washing with ethanol,and reused.Fast capturing,high sorption capacity,rapid separation,and good reusability make the PAN/ZIF-8(x%)/Fe_(3)O_(4)nanocomposites highly effective adsorbents for the separation of iodine from wastewater.Additionally,PAN/ZIF-8(50%)/Fe_(3)O_(4)bead can be considered as a potential new antibacterial agent for water and wastewater treatment.
基金supported by grants from the National Key Research and Development Program of China(2020YFA0907500)the National Natural Science Foundation of China(22193051,21277062,21806058)+1 种基金the Excellent Discipline Cultivation Project by JHUN(2023XKZ029)the PLA Logistics Research Project of China(2023).
文摘Remarkable antibacterial activity of BPA analogues especially for tetrabromobi-sphenol A against Staphylococcus aureus 25923(Sa25923)and methicillin-resistant Staphylococcus aureus(MRSA)has been reported in our previous studies.However,the toxic effects of the compounds as environmental contaminants on the endocrine system limited their applications in the field of medicine and health.Given the abuse of antibiotics has led to the emergence of multiple super-resistant bacteria,we considered that structural modifications based on the BPA structure will be available for molecular designing of potential antimicrobial agents without drug resistance.In this study,to further improve the antibacterial activity and reduce the biological toxicity,we performed the computational models to evaluate the binding affinities of BPA analogues to the potential target DltA protein in the biosynthesis of cell wall.A series of synthesized achiral analogues ofα,α,α′-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene(α,α,α′-TEIB)exhibited low minimum inhibitory concentration against Sa25923 and MRSA(2 or 1μg mL−1).Especially,the analogue A4 did not induce the drug-resistant mutants for all tested Gram-positive bacterial strains and exhibited relatively lower cytotoxicity in HepG2 cells.The developed classification model based on the light gradient boosting algorithm showed the superior performances on the internal robustness and generalization ability for the ligand-based virtual screening of bisphenol and polyphenol antimicrobial substances.Collectively,our findings suggest that the molecular structure ofα,α,α′-TEIB is promising as a scaffold,which is expected to achieve a breakthrough in the development of antibiotics which can prevent the invasion of MRSA and other super bacteria.
文摘Lack of antibacterial properties in resin-based composites (RBCs) is one of the flaws that cause the failure of filling clinically. Several agents have been incorporated to endow RBCs with antibacterial properties. In this review, we summarize the recent antibacterial agents between 2015 and 2020 using keywords of antibacterial or antimicrobial dental resin composites by PubMed databases. The most effective strategies are concerned with polymerizable monomers (50%), followed by filler particles (39%) and leachable agents (11%). A recent modification of the antibacterial agent is either by combining two agents from the same category or mixing agents from different categories in one. More than two methods were used in one study to assess antibacterial efficacy. The most common method was biofilm colony-forming units (CFUs) counting method (40%), followed by live/dead bacteria staining assay of biofilms (25%), metabolic activity assay of biofilms using MTT assay (16%), lactic acid production assay of biofilms (8%), agar diffusion test (8%), and other methods (3%) such as minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC).
基金supported by the National Natural Science Foundation of China(grant No.52072124 and 51972112)Natural Science Foundation of Shanghai(grant No.20zR1414900)+1 种基金Program of Shanghai Academic/Technology Research Leader(grant No.22XD1421100)The Fundamental Research Funds for the Central Universities,and the 111 project(grant No.B14018).
文摘Bacteria-caused wound infection greatly threatens human health,thus developing an efficient and safe antibacterial agent without drug resistance is still a great challenge.Herein,a confined vulcanization strategy is proposed to construct copper sulfides-loaded dual-mesoporous silica nanospheres(Cux-Sy@DMSNs)with various crystal phases for reactive oxygen species(ROS)-mediated and photothermal antibacterial application.With the pore confinement of DMSNs,the crystal phases of copper sulfides including CuS,Cu_(9)S_(5)and Cui.96S can be easily controlled by changing the vulcanization temperature.The relationships between the crystal phases and photothermal properties as well as peroxidase-like activity of copper sulfides were systematically investigated.Results show that the obtained CuS@DMSNs exhibited higher photothermal ability with remarkable photothermal conversion efficiency of 36.86%in the second near-infrared region(NIR-II)and better peroxidase-like activity,compared to those of Cu_(9)S_(5)@DMSNs and Cu_(1.96)S@DMSNs.As a result,the in vitro experiments showed the good antibacterial effect against both gram-negative E.coli and gram-positive S.aureus under 1064 nm laser irradiation and the presence of H_(2)O_(2).Besides,the CCK-8 assay indicated that CuS@p-DMSNs have minimal cytotoxicity against normal human umbilical vein endothelial cells at the ranged concentrations.Therefore,the resultant CuS@p-DMSNs could act as a promising antibacterial agent for deep wound bacterial infection treatment.
文摘Spinal epidural abscess (SEA) is a rare condition, and a delay in its diagnosis causes paralysis. In this study, we report two rare cases of delayed diagnosis of SEA whose conditions improved after a state of complete paralysis. The first case was a 71-year-old diabetic man who received a corticosteroid injection for shoulder pain that caused intensified pain. Thereafter, the patient developed paralysis of both legs in stage IV according to Heusner staging. Subsequently, he was diagnosed with multiple abscesses and sepsis. He was in a poor state of health. Therefore, we treated his epidural abscess conservatively. After a month, his muscle strength had improved to Heusner stage III-A, and he was transferred to another hospital. The second case was a 64-year-old diabetic man who received an epidural corticosteroid injection for lower back pain. However, the pain intensified and was admitted to the hospital for pyelonephritis. He developed paralysis in both of his arms and legs presenting as a Heusner stage IV, caused by a cervical epidural abscess. A laminoplasty was performed and paralysis was improved. However, the patient subsequently developed a left subcortical hemorrhage. He underwent surgery. However, his right hemiplegia persisted, and on Day 21, he was transferred back to the previous hospital with a Heusner III-A. We could improve the patients’ paralysis by cooperating closely with infectious disease specialists and spine surgeons, taking intensive care, applying antibacterial agents appropriately, and operating quickly.
基金the NSF of China(Grant No.11074010)the MOST of China(Grant No.2011DFA51450)for financial support
文摘Antibacterial Ag-agents are intensively applied as broad spectrum, high-stability, high-efficiency and high-safety inorganic antibacterial agents. We have developed a new kind of antibacterial Ag-agent, namely Ag_2-x(NH_4)xMo_3O_(10) ·3H_2O nanowires(NWs). Carrying Ag atoms in the lattice and Ag-rich nanoparticles on the surface, the Ag-doped NWs show strong antibacterial effects for a variety of bacteria including E.coli, Staphylococcus aureus, Candida albicans and Aspergil lus niger. By performing systematic comparison experiments, we have proven that the main antibacterial effects are neither resulted from the tiny amount of Ag+ions released from the Ag-doped NWs in aqueous solutions, nor resulted from Ag-rich nanoparticles of fragments of the NWs when they are slowly dissolved in the Martin broth. Instead, the effects are mainly resulted from a contact mechanism, under which, the Ag-doped NWs need to be physically in contact with the bacteria to be eliminated. This is a novel phenomenon observed in the interactions between nanomaterials and live cells, which is worthy of further investigation at the molecular scale. As the Ag-doped NWs are not dissolved in pure water or weak acids, one may find practical antibacterial applications in textile industry and food storage industry for these unique nanomaterials.
基金supported by the Taishan Scholar Foundation(No.tsqn201812074)the Young Talents Joint Fund of Shandong Province(No.ZR2019YQ07)+2 种基金the Original Innovation Project of Qingdao City(No.18-2-2-58-jch)the Open Fund of Shandong Key Laboratory of Biochemical Analysis(No.QUSTHX201901)the Ministry of Education,Singapore,Academic Research Grant R-279-000-538-114.
文摘Ultrasmall silver nanoclusters(Ag NCs)with rich surface chemistry and good biocompatibility are promising in antibacterial application,however,further development of Ag NCs for practical settings has been constrained by their relatively weak antibacterial activity.Using the nutritionally-rich medium for bacteria(e.g.,Luria-Bertani(LB)medium)to coat active Ag NCs could further improve their antibacterial activity.Here,we provide a delicate design of a highly efficient Ag NCs@ELB antibacterial agent(ELB denotes the extract of LB medium)by anchoring Ag NCs inside the ELB species via light irradiation.The as-designed Ag NCs with bacterium-favored nutrients on the surface can be easily swallowed by the bacteria,boosting the production of the intracellular reactive oxygen species(ROS,about 2-fold of that in the pristine Ag NCs).Subsequently,a higher concentration of ROS generated in Ag NCs@ELB leads to enhanced antibacterial activity,and enables to reduce the colony forming units(CFU)of both gram-positive and gram-negative bacteria with 3–4 orders of magnitude less than that treated with the pristine Ag NCs.In addition,the Ag NCs@ELB also shows good biocompatibility.This study suggests that surface engineering of active species(e.g.,Ag NCs)with nutritionally-rich medium of the bacteria is an efficient way to improve their antibacterial activity.
基金The authors gratefully acknowledge funding from the Post-Doctoral Fellowship Scheme for the projects"Development of Metal-Organic Framework/Graphene Oxide(MOF/GO)Composite Mixed Matrix Membrane for Gas Separation"(grant number PY/2015/05319)"Durable Hollow Fiber Composite Membrane with Bactericidal Properties for Wastewater Treatment"(grant number R.J090301.7809.4J181)through the Universiti Teknologi Malaysia(UTM)and HiCOE.
文摘We report a rapid method for synthesis of zeolitic imidazolate framework 8(ZIF-8)-decorated graphene oxide(GO)composites(ZGO)with good antibacterial properties.The ZGO composites were synthesized at room temperature with low GO to metal salt ratios.The samples were characterized by X-ray diffraction,transmission electron microscopy,Fourier transform infrared spectroscopy,thermal gravimetric analysis,and surface area analysis.The characterization results show that ZIF-8 with a size of approximately 120 nm is successfully decorated on the surface of GO sheets with the host ZIF-8 framework maintained in the synthesized composite,but there is a significant reduction in the Brunauer-Emmett-Teller surface area.The antibacterial activities of the samples against Escherichia coli ATCC 11229 and Staphylococcus aureus ATCC 6538 as model strains of gram-negative and-positive bacteria,respectively,were determined by disc diffusion and minimum inhibitory concentration(MIC)tests.ZGO-1.0(1 wt%of ratio of GO to metal salt)shows the highest antibacterial activity with MIC values required to inhibit bacterial growth of E.coli and S.aureus of 5 times lower than those of pristine ZIF-8.Different antibacterial mechanisms are proposed based on field-emission scanning electron microscope images of the two bacteria after contact with the synthesized composite.Overall,owing to the simple synthesis,good stability,low chemical usage,and excellent antibacterial activity of the ZGO composites,they show great potential for application in the field of microbial contamination control.
基金supported by grants from the National Natural Science Foundation of China (No. 21975165)Innovative Research Team Program of Sichuan Province (No. 2021JDTD0015)China Postdoctoral Science Foundation (No. 2021TQ0228)。
文摘The abuse of antibiotics causes severe bacterial resistance, and the shortage of antibiotics has created a global public health crisis. This situation has prompted people to develop new antibacterial agents independent of traditional antibiotics. Here, we created a series of photosensitive azobenzene-quaternary ammonium salt smart antibacterial agents by connecting azobenzene with amines with different chain lengths to improve the antibacterial selectivity of quaternary ammonium salt(QAS) and prevent the accumulation of active QAS in the environment. After trans-cis isomerization, the solubility of the title compound(compound 4) increased and the antibacterial property enhanced. The experimental results suggested that the antibacterial effect of compound 4 was significantly enhanced after 365 nm light irradiation, and it had photosensitive intelligent antibacterial activity and could be reused. Notably, we did not obtain any mutants of Staphylococcus aureus or Escherichia coli resistant to compound 4. In general,compound 4 has the advantages of high yield, photo-controllable antibacterial properties, reusability, and does not induce bacterial resistance. This photosensitive antibacterial compound provides a new idea for the construction of intelligent disinfectants and is expected to be a candidate for disinfectants in public facilities and medical architecture.
文摘The uniqueness of Zn is that, it is the second most abundant trace element in the animal body but can't be stored in the body, thus regular dietary intake is required. Zinc oxide(ZnO) nanoparticles(NP) particles are being extensively used in paints, skin lotions pigments, food, electronics appliances, biological and pharmaceutical applications and many more. Zinc oxide nanoparticles are the specially prepared mineral salt having particle size of 1 to 100 nm. It promotes growth can act as antibacterial agent,modulates the immunity and reproduction of the animals. Both in lower and higher doses of specifications it has exhibited a variety of effects on animal performances. Apart from being highly bioavailable, reports have already pointed out the growth promoting, antibacterial, immuno-modulatory and many more effects of nano zinc(nZn). These can be used at lower doses and can provide better result than the conventional Zn sources and indirectly prevents environmental contamination also. The toxicological studies provide mixed results in animal models. Studies been undertaken in diversified animal species and encouraging effects have been reported with nZn supplementation. However, there is a need to optimize the dose and duration of ZnO NP supplementation for human and livestock,depending on its biological effects. Actual bioavailability of ZnO NP in livestock is still to be worked out.In this review we have attempted to summarize, conclude the beneficial effects of nZnO and its possible usage as mineral supplement to different categories of human and livestock.
文摘Introduction Antibiotic use for acute otitis media(AOM)is one of the major sources of antimicrobial resistance.However,the effective minimal antibiotic duration for AOM remains unclear.Moreover,guidelines often recommend broad ranges(5-10 days)of antibiotic use,yet the clinical impact of such a wide window has not been assessed.Methods We systematically searched PubMed/MEDLINE,Embase,Scopus,Web of Science,and Cochrane Library from database inception to 6 October 2021.Network meta-analysis was conducted on randomized controlled trials that assessed antibiotic treatment for AOM in children(PROSPERO CRD42020196107).Results For amoxicillin and amoxicillin-clavulanate,7-day regimens were noninferior to 10-day regimens in clinical responses[amoxicillin:risk ratio(RR)0.919(95%CI 0.820-1.031),amoxicillin-clavulanate:RR 1.108(0.957-1.282)],except for≤2 years.For the third-generation cephalosporins,7-day and 10-day regimens had similar clinical responses compared to placebo[7-day:RR 1.420(1.190-1.694),10-day:RR 1.238(1.125-1.362)compared to placebo].However,5-day regimens of amoxicillin-clavulanate and third-generation cephalosporins were inferior to 10-day regimens.Compared to amoxicillin,a shorter treatment duration was tolerable with amoxicillin-clavulanate.Conclusions Our findings indicated that 1O days of antibiotic use may be unnecessarily long,while the treatment duration should be longer than 5 days.Otherwise,5-day regimens would be sufficient for a modest treatment goal.Our findings revealed that the current wide range of recommended antibiotic durations may have influenced the clinical outcome of AOM,and a narrower antibiotic duration window should be re-established.
