This study examined effects of dietary protein sources and levels on intestinal health of 21 to 35 d-old weaned piglets fed antibiotics-free diets. A total of 150 weaned piglets(21 d of age) were allotted to 5 dietary...This study examined effects of dietary protein sources and levels on intestinal health of 21 to 35 d-old weaned piglets fed antibiotics-free diets. A total of 150 weaned piglets(21 d of age) were allotted to 5 dietary treatment groups. Diets were formulated, based on corn-soybean meal, with different protein sources(fish meal and soy protein concentrate) to provide different dietary CP levels. Piglets within 5 dietary treatments were fed diets as follows, respectively: 1) control diet of 17% CP(control); 2) 19% CP diets formulated with more soy protein concentrate(SPC19); 3) fish meal(FM19); 4) 23.7% CP diets formulated with more soy protein concentrate(SPC23); 5) fish meal(FM23). The results showed that piglets from control group had higher ADG and lower incidence of diarrhea compared with those of other groups(P < 0.05). The incidence of diarrhea of piglets in FM19 group was lower than those from SPC23 group and FM23 group(P < 0.05). With the higher CP levels, villous height and villous height to crypt depth ratio of piglets in the duodenum and jejunum were decreased(P < 0.05), but crypt depth was increased(P < 0.05). Comparing control group and other groups, we found the expression of inflammatory cytokines interleukin-1β(IL-1β) and interferon-γ(IFN-γ) were increased(P < 0.05) in the jejunum and colon of piglets, as did cystic fibrosis transmembrane conductance regulators(CFTR) in the distal colon. The relative transcript abundance of Zonula occludens-1(ZO-1) in the jejunum, and occludin in the jejunum and ileum of piglets fed 23.7% CP diets were reduced compared with those fed control diet(P < 0.05). In conclusion, the 17% CP diet without in-feed antibiotics helped improve growth performance and relief of diarrhea of 21 to 35 d-old weaned piglets. Dietary CP level, rather than its source(either fish meal or soy protein concentrate), has more significant impacts on the growth performance and intestinal health of 21 to 35 d-old weaned piglets when fed antibiotics-free diets.展开更多
This study examined the impacts of different fiber sources on growth,immune status and gut health in weaned piglets fed antibiotic-free diets.Sixty piglets(BW=8.18±1.35 kg)were assigned to 3 dietary treatments ba...This study examined the impacts of different fiber sources on growth,immune status and gut health in weaned piglets fed antibiotic-free diets.Sixty piglets(BW=8.18±1.35 kg)were assigned to 3 dietary treatments based on BW and gender in a randomized complete block design(5 replicates/treatment and 4 piglets[2 barrows and 2 gilts]/replicate):(1)an antibiotic-free diet(control,CON);(2)CON+6%wheat bran(WB);(3)CON+4%sugar beet pulp(SBP).Dietary WB supplementation tended to increase ADG compared with CON from d 1 to 14(P-0.051)and from d 1 to 28(P-0.099).Supplementation of WB increased(P<0.05)G∶F compared with CON and SBP from d 1 to 14 and from d 1 to 28.Compared with CON,the addition of WB reduced(P<0.05)diarrhea rate from d 1 to 14 and tended(P=0.054)to reduce diarrhea rate from d 1 to 28.The addition of WB decreased(P<0.05)serum diamine oxidase activity on d 14,and up-regulated(P<0.05)ileal mRNA levels of occludin on d 28 when compared with CON.Piglets fed WB showed decreased(P<0.05)serum interleukin-6 levels compared to those fed SBP and decreased(P<0.05)ileal interleukin-8 levels compared to those fed CON and SBP on d 28.Supple-mentation of WB increased(P<0.05)serum levels of immunoglobulin A(IgA),IgG and IgM compared with SBP on d 14,and increased(P<0.05)the levels of serum IgA and ileal sIgA compared with CON and SBP on d 28.Piglets fed WB showed an enhanced(P<0.05)α-diversity of cecal microbiota than those fed SBP,while piglets fed SBP showed reduced(P<0.05)α-diversity of cecal microbiota than those fed CON.Compared with CON,the addition of WB elevated(P<0.05)the abundance of Lachnospira and cecal butyric acid level.Piglets fed WB also showed increased(P<0.05)abundances of Lachnospira and unclassified_f_Lachnospiraceae compared with those fed SBP.Collectively,the supplementation of WB to antibiotic-free diets improved performance,immune responses,gut barrier function and microbiota compared with the CON and SBP fed piglets.Therefore,supplementing weaned piglets with WB was more effective than SBP.展开更多
Based on the theory of planned behavior( TPB),Taking 399 livestock and poultry farms and households in Shandong Province as samples,risk cognitive variables were introduced. Besides,with the aid of the structural equa...Based on the theory of planned behavior( TPB),Taking 399 livestock and poultry farms and households in Shandong Province as samples,risk cognitive variables were introduced. Besides,with the aid of the structural equation model( SEM) and partial least squares method( PLS),through an empirical analysis on antibiotic prophylactic behavior of livestock and poultry breeding farms and households in the context of " antibiotic free" production,the response mechanism of " antibiotic free" production was explored. Results indicated that the use of antibiotic prophylaxis by livestock and poultry farms and households is still very common. In the observation samples,61. 4% clearly expressed they would use antibiotic prophylaxis; the understanding of hazard of improper antibiotic prophylaxis was inadequate,only 32. 3% breeding households believed that the overuse of antibiotic prophylaxis is the main reason leading to excessive drug residue in animal products. This study was in line with the process of deduction of TPB. The breeding households' reduction of antibiotic prophylaxis is influenced by their intentions,while the intention is influenced by the attitude,subjective norms and perceptual behavior control; different risks have different influences,but most risks have greater influence on perceptual behavior control,because the perceptual behavior control determines whether breeding households have the ability of implementing the corresponding behavior.展开更多
Helicobacter pylori(H.pylori)infection remains the leading cause of gastric adenocarcinoma,and its eradication primarily relies on the prolonged and intensive use of two antibiotics.However,antibiotic resistance has b...Helicobacter pylori(H.pylori)infection remains the leading cause of gastric adenocarcinoma,and its eradication primarily relies on the prolonged and intensive use of two antibiotics.However,antibiotic resistance has become a compelling health issue,leading to H.pylori eradication treatment failure worldwide.Additionally,the powerlessness of antibiotics against biofilms,as well as intracellular H.pylori and the long-term damage of antibiotics to the intestinal microbiota,have also created an urgent demand for antibiotic-free approaches.Herein,we describe an antibiotic-free,multifunctional copperorganic framework(HKUST-1)platform encased in a lipid layer comprising phosphatidic acid(PA),rhamnolipid(RHL),and cholesterol(CHOL),enveloped in chitosan(CS),and loaded in an ascorbyl palmitate(AP)hydrogel:AP@CS@Lip@HKUST-1.This platform targets inflammatory sites where H.pylori aggregates through electrostatic attraction.Then,hydrolysis by matrix metalloproteinases(MMPs)releases CS-encased nanoparticles,disrupting bacterial urease activity and membrane integrity.Additionally,RHL disperses biofilms,while PA promotes lysosomal acidification and activates host autophagy,enabling clearance of intracellular H.pylori.Furthermore,AP@CS@Lip@HKUST-1 alleviates inflammation and enhances mucosal repair through delayed Cu^(2+) release while preserving the intestinal microbiota.Collectively,this platform presents an advanced therapeutic strategy for eradicating persistent H.pylori infection without inducing drug resistance.展开更多
Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poult...Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poultry producers,despite substantial efforts in prevention and control.Antibiotics have been used not only for the treatment and prevention of such diseases,but also for growth promotion.Consequently,these practices have been linked to the selection and spread of antimicrobial resistant bacteria which constitute a significant global threat to humans,ani-mals,and the environment.To break down the antimicrobial resistance(AMR),poultry producers are restricting the antimicrobial use(AMU)while adopting the antibiotic-free(ABF)and organic production practices to satisfy consum-ers’demands.However,it is not well understood how ABF and organic poultry production practices influence AMR profiles in the poultry gut microbiome.Various Gram-negative(Salmonella enterica serovars,Campylobacter jejuni/coli,E.coli)and Gram-positive(Enterococcus spp.,Staphylococcus spp.and C.perfringens)bacteria harboring multiple AMR determinants have been reported in poultry including organically-and ABF-raised chickens.In this review,we discussed major poultry production systems(conventional,ABF and organic)and their impacts on AMR in some potential pathogenic Gram-negative and Gram-positive bacteria which could allow identifying issues and opportuni-ties to develop efficient and safe production practices in controlling pathogens.展开更多
The emergence of antibiotic resistance in bacteria is a major public-health issue.Synthesis of efficient antibiotic-free material is very important for fighting bacterial infection-related diseases.Herein,red-carbon d...The emergence of antibiotic resistance in bacteria is a major public-health issue.Synthesis of efficient antibiotic-free material is very important for fighting bacterial infection-related diseases.Herein,red-carbon dots(R-CDs)with a broad range of spectral absorption(350–700 nm)from organic bactericides or intermediates were synthesized through a solvothermal route.The prepared R-CDs not only had intrinsic antibacterial activities,but also could kill multidrug-resistant bacteria(multidrug-resistant Acinetobacter baumannii(MRAB)and multidrug-resistant Staphylococcus aureus(MRSA))effectively by generating reactive oxygen species.Furthermore,R-CDs could eliminate and inhibit the formation of MRAB biofilms,while conferring few side effects on normal cells.A unique property of R-CDs was demonstrated upon in vivo treatment of antibiotic-sensitive MRABinduced infected wounds.These data suggested that this novel R-CDs-based strategy might enable the design of nextgeneration agents to fight drug-resistant bacteria.展开更多
Prosthetic joint infection(PJI)is the most serious complication following total joint arthroplasty,this being because it is associated with,among other things,high morbidity and low quality of life,is difficult to pre...Prosthetic joint infection(PJI)is the most serious complication following total joint arthroplasty,this being because it is associated with,among other things,high morbidity and low quality of life,is difficult to prevent,and is very challenging to treat/manage.The many shortcomings of antibiotic-loaded poly(methyl methacrylate)(PMMA)bone cement(ALBC)as an agent for preventing and treating/managing PJI are well-known.One is that microorganisms responsible for most PJI cases,such as methicillin-resistant S.aureus,have developed or are developing resistance to gentamicin sulfate,which is the antibiotic in the vast majority of approved ALBC brands.This has led to many research efforts to develop cements that do not contain gentamicin(or,for that matter,any antibiotic)but demonstrate excellent antimicrobial efficacy.There is a sizeable body of literature on these socalled“antibiotic-free antimicrobial”PMMA bone cements(AFAMBCs).The present work is a comprehensive and critical review of this body.In addition to summaries of key trends in results of characterization studies of AFAMBCs,the attractive features and shortcomings of the literature are highlighted.Shortcomings provide motivation for future work,with some ideas being formulation of a new generation of AFAMBCs by,example,adding a nanostructured material and/or an extract from a natural product to the powder and/or liquid of the basis cement,respectively.展开更多
The present study was conducted to evaluate the effect of dietary folic acid on the growth performance,intestinal morphology,and intestinal epithelial cells renewal in post-weaning piglets.Twenty-eight piglets(weaned ...The present study was conducted to evaluate the effect of dietary folic acid on the growth performance,intestinal morphology,and intestinal epithelial cells renewal in post-weaning piglets.Twenty-eight piglets(weaned at day 21,initial body weight of 6.73±0.62 kg)were randomly allotted to 4 treat-ments with 7 pens per diet and 1 piglet per pen.The piglets were fed the same antibiotic-free and zinc oxide-free basal diets supplemented with folic acid at 0,3,9,and 18 mg/kg for 14 days.The results showed that dietary supplementation with folic acid increased villus height(VH)(P=0.003;linear,P=0.001),VH-to-crypt depth(VH:CD)ratio(P=0.002;linear,P=0.001),villus surface area(VSA)(P=0.026;linear,P=0.010).The analyzed parameters ADG,serum urea nitrogen(BUN)content,VH,VSA,and serum folate(SF)concentration responded linearly to the dietary folic acid concentration when the dietary folic acid concentration was below 4.42,5.26,4.79,3.47,and 3.53 mg/kg respectively(R2=0.995,0.995,0.999,0.999,0.872,P=0.09,0.07,0.09,0.09,0.36,respectively),as assessed by a two-linear broken-line regression.Above these breakpoints,the response of ADG,VH,VSA,and SF plateaued in response to changes in dietary folic acid concentration.Moreover,dietary supplementation with folic acid significantly increased the lactase(P=0.001;linear,P=0.001)and sucrase activities(P=0.021;linear,P=0.010)in the jejunal mucosa of weaned piglets.The mRNA expression of solute carrier family 6 member 19(SLC6a19),solute carrier family 1 member 1(SLC7a1),tumor necrosis factor-α(TNF-α),the number of Ki67 positive cells,and cell shedding rate had a significant linear contrast(P=0.023,0.021,0.038,0.049,and 0.008,respectively)in dietary folic acid groups.In conclusion,our results indicate that folic acid supplementation can improve the growth performance and intestinal morphology of weaned piglets by maintaining the balance of epithelial cell renewal.展开更多
Effective management of hard-to-close skin wounds is a challenging issue due to several co-morbidities in affected patients.Particularly,infections represent a major obstacle in wound healing.The design of efficient w...Effective management of hard-to-close skin wounds is a challenging issue due to several co-morbidities in affected patients.Particularly,infections represent a major obstacle in wound healing.The design of efficient wound treatments thus represents an urgent need.Injectable drug delivery hydrogels with intrinsic antimicrobial and antifungal properties were herein designed for perspective application in the mini-invasive treatment of hard-to-close wounds.First,an amphiphilic polyurethane was synthesized from Poloxamer■407 macrodiol and N-Boc diethanolamine chain extender(DHP407,M_(w)=33 kDa).Chain-extension reaction step was optimized to maximize the formation of-NH groups along the polymer chains(4.5×10^(20)±1.8×10^(19)-NH groups/g polymer),after Boc-caging group removal(D-DHP407).DHP407 and D-DHP407 water-based solutions were thermosensitive with slightly different Critical Micellar Concentration(17.5μg/mL vs.19.7μg/mL)and cluster hydrodynamic diameter(235.6±19.9 nm vs.260.1±20.5 nm),and similar Critical Micellar Temperature(22.5℃ vs.23.1℃).A polyurethane solution concentration(15%w/V)was selected by tube-inverting test and rheological analysis showing injectability,as evidenced by sol-to-gel transition at 27.7±0.6℃ for DHP407 and 29.7±0.6℃ for D-DHP407,within few minutes,at similar gelation kinetics.DHP407 and D-DHP407 hydrogels showed controlled release of Bovine Serum Albumin(BSA)model protein(1 mg/mL),with no burst phenomena.BSA released from DHP407 and D-DHP407 hydrogels at 24 h was 33.7±5.0% and 24.6±1.2%,respectively.D-DHP407 hydrogel was biocompatible and able to support NIH-3T3 cell proliferation.Furthermore,D-DHP407 hydrogel showed intrinsic antifungal and antibacterial activity against C.albicans and Gram-positive S.aureus and Gram-negative E.coli bacteria,injectability and capability to retain shape post-injection,making it promising for future use in the management of hard-to-close skin wounds.展开更多
基金financially supported by China Agriculture Research System (CARS-36) (2013B060400039 to 2011A020102009)National Basic Research Program of China (2013CB127301, and 2013CB127304)+1 种基金Science and Technology Planning Project of Guangdong Province (2013B060400039,2013A061401020)Special Program for Guangdong Research Institutions' Innovation and Construction(2012B060600005)
文摘This study examined effects of dietary protein sources and levels on intestinal health of 21 to 35 d-old weaned piglets fed antibiotics-free diets. A total of 150 weaned piglets(21 d of age) were allotted to 5 dietary treatment groups. Diets were formulated, based on corn-soybean meal, with different protein sources(fish meal and soy protein concentrate) to provide different dietary CP levels. Piglets within 5 dietary treatments were fed diets as follows, respectively: 1) control diet of 17% CP(control); 2) 19% CP diets formulated with more soy protein concentrate(SPC19); 3) fish meal(FM19); 4) 23.7% CP diets formulated with more soy protein concentrate(SPC23); 5) fish meal(FM23). The results showed that piglets from control group had higher ADG and lower incidence of diarrhea compared with those of other groups(P < 0.05). The incidence of diarrhea of piglets in FM19 group was lower than those from SPC23 group and FM23 group(P < 0.05). With the higher CP levels, villous height and villous height to crypt depth ratio of piglets in the duodenum and jejunum were decreased(P < 0.05), but crypt depth was increased(P < 0.05). Comparing control group and other groups, we found the expression of inflammatory cytokines interleukin-1β(IL-1β) and interferon-γ(IFN-γ) were increased(P < 0.05) in the jejunum and colon of piglets, as did cystic fibrosis transmembrane conductance regulators(CFTR) in the distal colon. The relative transcript abundance of Zonula occludens-1(ZO-1) in the jejunum, and occludin in the jejunum and ileum of piglets fed 23.7% CP diets were reduced compared with those fed control diet(P < 0.05). In conclusion, the 17% CP diet without in-feed antibiotics helped improve growth performance and relief of diarrhea of 21 to 35 d-old weaned piglets. Dietary CP level, rather than its source(either fish meal or soy protein concentrate), has more significant impacts on the growth performance and intestinal health of 21 to 35 d-old weaned piglets when fed antibiotics-free diets.
基金the National Natural Science Foundation of China(31772612)the Beijing Municipal Natural Science Foundation(6202019).
文摘This study examined the impacts of different fiber sources on growth,immune status and gut health in weaned piglets fed antibiotic-free diets.Sixty piglets(BW=8.18±1.35 kg)were assigned to 3 dietary treatments based on BW and gender in a randomized complete block design(5 replicates/treatment and 4 piglets[2 barrows and 2 gilts]/replicate):(1)an antibiotic-free diet(control,CON);(2)CON+6%wheat bran(WB);(3)CON+4%sugar beet pulp(SBP).Dietary WB supplementation tended to increase ADG compared with CON from d 1 to 14(P-0.051)and from d 1 to 28(P-0.099).Supplementation of WB increased(P<0.05)G∶F compared with CON and SBP from d 1 to 14 and from d 1 to 28.Compared with CON,the addition of WB reduced(P<0.05)diarrhea rate from d 1 to 14 and tended(P=0.054)to reduce diarrhea rate from d 1 to 28.The addition of WB decreased(P<0.05)serum diamine oxidase activity on d 14,and up-regulated(P<0.05)ileal mRNA levels of occludin on d 28 when compared with CON.Piglets fed WB showed decreased(P<0.05)serum interleukin-6 levels compared to those fed SBP and decreased(P<0.05)ileal interleukin-8 levels compared to those fed CON and SBP on d 28.Supple-mentation of WB increased(P<0.05)serum levels of immunoglobulin A(IgA),IgG and IgM compared with SBP on d 14,and increased(P<0.05)the levels of serum IgA and ileal sIgA compared with CON and SBP on d 28.Piglets fed WB showed an enhanced(P<0.05)α-diversity of cecal microbiota than those fed SBP,while piglets fed SBP showed reduced(P<0.05)α-diversity of cecal microbiota than those fed CON.Compared with CON,the addition of WB elevated(P<0.05)the abundance of Lachnospira and cecal butyric acid level.Piglets fed WB also showed increased(P<0.05)abundances of Lachnospira and unclassified_f_Lachnospiraceae compared with those fed SBP.Collectively,the supplementation of WB to antibiotic-free diets improved performance,immune responses,gut barrier function and microbiota compared with the CON and SBP fed piglets.Therefore,supplementing weaned piglets with WB was more effective than SBP.
文摘Based on the theory of planned behavior( TPB),Taking 399 livestock and poultry farms and households in Shandong Province as samples,risk cognitive variables were introduced. Besides,with the aid of the structural equation model( SEM) and partial least squares method( PLS),through an empirical analysis on antibiotic prophylactic behavior of livestock and poultry breeding farms and households in the context of " antibiotic free" production,the response mechanism of " antibiotic free" production was explored. Results indicated that the use of antibiotic prophylaxis by livestock and poultry farms and households is still very common. In the observation samples,61. 4% clearly expressed they would use antibiotic prophylaxis; the understanding of hazard of improper antibiotic prophylaxis was inadequate,only 32. 3% breeding households believed that the overuse of antibiotic prophylaxis is the main reason leading to excessive drug residue in animal products. This study was in line with the process of deduction of TPB. The breeding households' reduction of antibiotic prophylaxis is influenced by their intentions,while the intention is influenced by the attitude,subjective norms and perceptual behavior control; different risks have different influences,but most risks have greater influence on perceptual behavior control,because the perceptual behavior control determines whether breeding households have the ability of implementing the corresponding behavior.
基金supported by the National Natural Science Foundation of China(No.82072051)the Strategic Consulting Research Project of the Chinese Academy of Engineering(No.2021-ZX-12,China)+3 种基金the Project of the Shanghai Municipal Health Commission(No.2019SY001,China)the Shanghai Clinical Medical Research Center for Digestive Diseases Project(No.19MC1910200,China)the Shanghai Outstanding Academic Leaders Program(No.21XD14049,China)the Nanchang University Graduate Student Innovation Fund(No.YC2023-B102,China).
文摘Helicobacter pylori(H.pylori)infection remains the leading cause of gastric adenocarcinoma,and its eradication primarily relies on the prolonged and intensive use of two antibiotics.However,antibiotic resistance has become a compelling health issue,leading to H.pylori eradication treatment failure worldwide.Additionally,the powerlessness of antibiotics against biofilms,as well as intracellular H.pylori and the long-term damage of antibiotics to the intestinal microbiota,have also created an urgent demand for antibiotic-free approaches.Herein,we describe an antibiotic-free,multifunctional copperorganic framework(HKUST-1)platform encased in a lipid layer comprising phosphatidic acid(PA),rhamnolipid(RHL),and cholesterol(CHOL),enveloped in chitosan(CS),and loaded in an ascorbyl palmitate(AP)hydrogel:AP@CS@Lip@HKUST-1.This platform targets inflammatory sites where H.pylori aggregates through electrostatic attraction.Then,hydrolysis by matrix metalloproteinases(MMPs)releases CS-encased nanoparticles,disrupting bacterial urease activity and membrane integrity.Additionally,RHL disperses biofilms,while PA promotes lysosomal acidification and activates host autophagy,enabling clearance of intracellular H.pylori.Furthermore,AP@CS@Lip@HKUST-1 alleviates inflammation and enhances mucosal repair through delayed Cu^(2+) release while preserving the intestinal microbiota.Collectively,this platform presents an advanced therapeutic strategy for eradicating persistent H.pylori infection without inducing drug resistance.
基金supported by Agriculture and Agri-Food Canada to M.S.Diarra through the Genomics Research and Development Initiative (PSS#1858 J-001262) and A-Base (PSS#3441,J-002363) projects on “Mitigating Antimicrobial Resistance”.
文摘Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poultry producers,despite substantial efforts in prevention and control.Antibiotics have been used not only for the treatment and prevention of such diseases,but also for growth promotion.Consequently,these practices have been linked to the selection and spread of antimicrobial resistant bacteria which constitute a significant global threat to humans,ani-mals,and the environment.To break down the antimicrobial resistance(AMR),poultry producers are restricting the antimicrobial use(AMU)while adopting the antibiotic-free(ABF)and organic production practices to satisfy consum-ers’demands.However,it is not well understood how ABF and organic poultry production practices influence AMR profiles in the poultry gut microbiome.Various Gram-negative(Salmonella enterica serovars,Campylobacter jejuni/coli,E.coli)and Gram-positive(Enterococcus spp.,Staphylococcus spp.and C.perfringens)bacteria harboring multiple AMR determinants have been reported in poultry including organically-and ABF-raised chickens.In this review,we discussed major poultry production systems(conventional,ABF and organic)and their impacts on AMR in some potential pathogenic Gram-negative and Gram-positive bacteria which could allow identifying issues and opportuni-ties to develop efficient and safe production practices in controlling pathogens.
基金supported by the National Natural Science Foundation of China(NSFC,21925802,21878039,21808028,22022803 and 22078046)the NSFC-Liaoning United Fund(U1908202)the National Key Research and Development Plan(2018AAA0100301)。
文摘The emergence of antibiotic resistance in bacteria is a major public-health issue.Synthesis of efficient antibiotic-free material is very important for fighting bacterial infection-related diseases.Herein,red-carbon dots(R-CDs)with a broad range of spectral absorption(350–700 nm)from organic bactericides or intermediates were synthesized through a solvothermal route.The prepared R-CDs not only had intrinsic antibacterial activities,but also could kill multidrug-resistant bacteria(multidrug-resistant Acinetobacter baumannii(MRAB)and multidrug-resistant Staphylococcus aureus(MRSA))effectively by generating reactive oxygen species.Furthermore,R-CDs could eliminate and inhibit the formation of MRAB biofilms,while conferring few side effects on normal cells.A unique property of R-CDs was demonstrated upon in vivo treatment of antibiotic-sensitive MRABinduced infected wounds.These data suggested that this novel R-CDs-based strategy might enable the design of nextgeneration agents to fight drug-resistant bacteria.
文摘Prosthetic joint infection(PJI)is the most serious complication following total joint arthroplasty,this being because it is associated with,among other things,high morbidity and low quality of life,is difficult to prevent,and is very challenging to treat/manage.The many shortcomings of antibiotic-loaded poly(methyl methacrylate)(PMMA)bone cement(ALBC)as an agent for preventing and treating/managing PJI are well-known.One is that microorganisms responsible for most PJI cases,such as methicillin-resistant S.aureus,have developed or are developing resistance to gentamicin sulfate,which is the antibiotic in the vast majority of approved ALBC brands.This has led to many research efforts to develop cements that do not contain gentamicin(or,for that matter,any antibiotic)but demonstrate excellent antimicrobial efficacy.There is a sizeable body of literature on these socalled“antibiotic-free antimicrobial”PMMA bone cements(AFAMBCs).The present work is a comprehensive and critical review of this body.In addition to summaries of key trends in results of characterization studies of AFAMBCs,the attractive features and shortcomings of the literature are highlighted.Shortcomings provide motivation for future work,with some ideas being formulation of a new generation of AFAMBCs by,example,adding a nanostructured material and/or an extract from a natural product to the powder and/or liquid of the basis cement,respectively.
基金Key Programs of frontier scientific research of the Chinese Academy of Sciences(Grant No.QYZDY-SSW-SMC008)National Key R&D Program(Grant No.2016YFD0501201)Natural Science Foundation of Hunan Province(Grant No.2017JJ1020).
文摘The present study was conducted to evaluate the effect of dietary folic acid on the growth performance,intestinal morphology,and intestinal epithelial cells renewal in post-weaning piglets.Twenty-eight piglets(weaned at day 21,initial body weight of 6.73±0.62 kg)were randomly allotted to 4 treat-ments with 7 pens per diet and 1 piglet per pen.The piglets were fed the same antibiotic-free and zinc oxide-free basal diets supplemented with folic acid at 0,3,9,and 18 mg/kg for 14 days.The results showed that dietary supplementation with folic acid increased villus height(VH)(P=0.003;linear,P=0.001),VH-to-crypt depth(VH:CD)ratio(P=0.002;linear,P=0.001),villus surface area(VSA)(P=0.026;linear,P=0.010).The analyzed parameters ADG,serum urea nitrogen(BUN)content,VH,VSA,and serum folate(SF)concentration responded linearly to the dietary folic acid concentration when the dietary folic acid concentration was below 4.42,5.26,4.79,3.47,and 3.53 mg/kg respectively(R2=0.995,0.995,0.999,0.999,0.872,P=0.09,0.07,0.09,0.09,0.36,respectively),as assessed by a two-linear broken-line regression.Above these breakpoints,the response of ADG,VH,VSA,and SF plateaued in response to changes in dietary folic acid concentration.Moreover,dietary supplementation with folic acid significantly increased the lactase(P=0.001;linear,P=0.001)and sucrase activities(P=0.021;linear,P=0.010)in the jejunal mucosa of weaned piglets.The mRNA expression of solute carrier family 6 member 19(SLC6a19),solute carrier family 1 member 1(SLC7a1),tumor necrosis factor-α(TNF-α),the number of Ki67 positive cells,and cell shedding rate had a significant linear contrast(P=0.023,0.021,0.038,0.049,and 0.008,respectively)in dietary folic acid groups.In conclusion,our results indicate that folic acid supplementation can improve the growth performance and intestinal morphology of weaned piglets by maintaining the balance of epithelial cell renewal.
文摘Effective management of hard-to-close skin wounds is a challenging issue due to several co-morbidities in affected patients.Particularly,infections represent a major obstacle in wound healing.The design of efficient wound treatments thus represents an urgent need.Injectable drug delivery hydrogels with intrinsic antimicrobial and antifungal properties were herein designed for perspective application in the mini-invasive treatment of hard-to-close wounds.First,an amphiphilic polyurethane was synthesized from Poloxamer■407 macrodiol and N-Boc diethanolamine chain extender(DHP407,M_(w)=33 kDa).Chain-extension reaction step was optimized to maximize the formation of-NH groups along the polymer chains(4.5×10^(20)±1.8×10^(19)-NH groups/g polymer),after Boc-caging group removal(D-DHP407).DHP407 and D-DHP407 water-based solutions were thermosensitive with slightly different Critical Micellar Concentration(17.5μg/mL vs.19.7μg/mL)and cluster hydrodynamic diameter(235.6±19.9 nm vs.260.1±20.5 nm),and similar Critical Micellar Temperature(22.5℃ vs.23.1℃).A polyurethane solution concentration(15%w/V)was selected by tube-inverting test and rheological analysis showing injectability,as evidenced by sol-to-gel transition at 27.7±0.6℃ for DHP407 and 29.7±0.6℃ for D-DHP407,within few minutes,at similar gelation kinetics.DHP407 and D-DHP407 hydrogels showed controlled release of Bovine Serum Albumin(BSA)model protein(1 mg/mL),with no burst phenomena.BSA released from DHP407 and D-DHP407 hydrogels at 24 h was 33.7±5.0% and 24.6±1.2%,respectively.D-DHP407 hydrogel was biocompatible and able to support NIH-3T3 cell proliferation.Furthermore,D-DHP407 hydrogel showed intrinsic antifungal and antibacterial activity against C.albicans and Gram-positive S.aureus and Gram-negative E.coli bacteria,injectability and capability to retain shape post-injection,making it promising for future use in the management of hard-to-close skin wounds.
