Dental implants have restored masticatory function to over 100000000 individuals,yet almost 1000000 implants fail each year due to peri-implantitis,a disease triggered by peri-implant microbial dysbiosis.Our ability t...Dental implants have restored masticatory function to over 100000000 individuals,yet almost 1000000 implants fail each year due to peri-implantitis,a disease triggered by peri-implant microbial dysbiosis.Our ability to prevent and treat peri-implantitis is hampered by a paucity of knowledge of how these biomes are acquired and the factors that engender normobiosis.Therefore,we combined a 3-month interventional study of 15 systemically and periodontally healthy adults with whole genome sequencing,finescale enumeration and graph theoretics to interrogate colonization dynamics in the pristine peri-implant sulcus.We discovered that colonization trajectories of implants differ substantially from adjoining teeth in acquisition of new members and development of functional synergies.Source-tracking algorithms revealed that this niche is initially seeded by bacteria trapped within the coverscrew chamber during implant placement.These pioneer species stably colonize the microbiome and exert a sustained influence on the ecosystem by serving as anchors of influential hubs and by providing functions that enable cell replication and biofilm maturation.Unlike the periodontal microbiome,recruitment of new members to the peri-implant community occurs on nepotistic principles.Maturation is accompanied by a progressive increase in anaerobiosis,however,the predominant functionalities are oxygen-dependent over the 12-weeks.The peri-implant community is easily perturbed following crown placement,but demonstrates remarkable resilience;returning to pre-perturbation states within three weeks.This study highlights important differences in the development of the periodontal and peri-implant ecosystems,and signposts the importance of placing implants in periodontally healthy individuals or following the successful resolution of periodontal disease.展开更多
Saline-alkali soil severely reduces the productivity of crops,including maize(Zea mays).Although several genes associated with saline-alkali tolerance have been identified in maize,the underlying regulatory mechanism ...Saline-alkali soil severely reduces the productivity of crops,including maize(Zea mays).Although several genes associated with saline-alkali tolerance have been identified in maize,the underlying regulatory mechanism remains elusive.Here,we report a direct link between colonization by arbuscular mycorrhizal fungi(AMF)and saline-alkali tolerance in maize.We identify s75,a natural maize mutant that cannot survive under moderate saline-alkali soil conditions or establish AM symbioses.The saline-alkali hypersensitive phenotype of s75 is caused by a 1340-bp deletion in Zm00001d033915,designated as ZmL75.This gene encodes a glycerol-3-phosphate acyltransferase localized in the endoplasmic reticulum,and is responsible for AMF colonization.ZmL75 expression levels in roots correspond with the root length colonization(RLC)rate during early vegetative development.Notably,the s75 mutant line shows a complete loss of AMF colonization,along with alterations in the diversity and structure of its root fungal microbiota.Conversely,overexpression of ZmL75 increases the RLC rate and enhances tolerance to saline-alkali soil conditions.These results suggest that ZmL75 is required for symbiosis with AMF,which directly improves saline-alkali tolerance.Our findings provide insights into maize-AMF interactions and offer a potential strategy for maize improvement.展开更多
In the early years of the 20th century,Britain sought to compete with Russia for dominance in East Asia,and set its sights on the strategic location of Xizang.Smallpox virus epidemics have been documented in Xizang si...In the early years of the 20th century,Britain sought to compete with Russia for dominance in East Asia,and set its sights on the strategic location of Xizang.Smallpox virus epidemics have been documented in Xizang since the 7th century,and smallpox remained a major public health issue in Xizang until the early 20th century.The British colonizers learned from their experience of passing on biological science and technology in India and carried out a series of medical activities in Xizang,the most influential of which was the smallpox vaccination for the people of Gyantse and other places.This paper examines the history of the fight against smallpox in Xizang from 1900 to 1907,and studies the historical process of British colonial expansion in Xizang,as well as the interaction between the Qing government and the British invaders in medical and healthcare events such as vaccination in Xizang.展开更多
Plasmid pVK1001 which carried the gfp gene of GFPmut2, a mutant of GFP, was introduced into Azospirillum brasilense Yu62 by electroporation. Maize seedlings were inoculated with the GFP-labelled baeteria and grown gno...Plasmid pVK1001 which carried the gfp gene of GFPmut2, a mutant of GFP, was introduced into Azospirillum brasilense Yu62 by electroporation. Maize seedlings were inoculated with the GFP-labelled baeteria and grown gnotobiotically in flask with semi-solid agar medium. Observations were performed with confocal laser scanning microscopy (CLSM) and electron microscopy, respectively, at 8 d and 12 d after inoculation. Confocal laser scanning microscopy showed that A. brasilense Yu62 could penetrate into the cortex tissue, colonizing in the intercellular spaces of the parenchyma cells of the cortex tissue. Transmission and scanning electron microscopy (TEM) showed that the majority of the bacteria colonized on the root surface and only a minority of them resided in the root interior.展开更多
Background Weaning-induced diarrhoea and growth retardation in piglets are associated with impaired intestinal barrier function and decreased levels of colonic short-chain fatty acids(SCFAs).Although SCFA supplementat...Background Weaning-induced diarrhoea and growth retardation in piglets are associated with impaired intestinal barrier function and decreased levels of colonic short-chain fatty acids(SCFAs).Although SCFA supplementation has been proposed to mitigate these issues,the efficacy and optimal dosage of sodium isobutyrate remain unclear.Results We investigated the effects of sodium isobutyrate supplementation(500,1,000,2,000,and 4,000 mg/kg diet)on weaned piglets(Duroc×Landrace×Yorkshire,28 d of age;n=8).After a 28-d feeding trial,supplementation at 500–2,000 mg/kg significantly improved average daily gain and feed efficiency and reduced diarrhoea frequency,with maximal benefits observed at 1,000 mg/kg(P<0.0001).Additionally,500–1,000 mg/kg sodium isobutyrate supplementation increased the apparent digestibility of crude protein,organic matter,and crude fibre(P<0.05).Serum biochemical parameters were unaffected,although secretory immunoglobulin A(SIgA)levels significantly increased upon supplementation with 500–1,000 mg/kg(P<0.05).16S rRNA gene sequencing indicated that sodium isobutyrate increased the abundance of beneficial colonic microbiota.The 1,000 mg/kg group presented the most pronounced effect,with a significant increase of the relative abundance of Prevotella and the greatest improvement in SCFA concentrations(P<0.05).Metabolomics revealed elevated levels of colonic indole-3-lactic acid and 3-hydroxybutyrate upon supplementation with 1,000 mg/kg(P<0.05).Transcriptomic analyses indicated activation of protein digestion and absorption pathways,and PI3K-Akt signalling,marked by TSG-6 upregulation and the suppression of ISG15 and DDIT4 expression(P<0.05).Supplementation with 1,000 mg/kg was associated with improved intestinal barrier-related markers,including reduced serum D-lactate,diamine oxidase,and lipopolysaccharide levels,increased tight junction protein expression;activation of G protein-coupled receptors;and inhibition of TLR4/MyD88/NF-κB signalling(P<0.05),suggesting enhanced barrier function.Conclusions In conclusion,dietary supplementation with 1,000 mg/kg sodium isobutyrate was associated with improved intestinal morphology,reduced serum permeability,increased expression of tight junction proteins,and enhanced immune function in weaned piglets,suggesting enhanced colonic barrier function and providing dosage guidance and mechanistic insights for future applications.展开更多
The objective of this study was to evaluate the effect of a novel feed additive on chicken intestinal colonization and carcass contamination by Campylobacterjejuni. The feed additive was composed of microencapsulated ...The objective of this study was to evaluate the effect of a novel feed additive on chicken intestinal colonization and carcass contamination by Campylobacterjejuni. The feed additive was composed of microencapsulated organic acids and essential oils （OA/EO）. The feed additive tested was provided by Jefo Nutrition Inc., St-Hyacinthe, Quebec, Canada. Day-old birds were separated into two rooms and subdivided into two groups. Chicken were fed with OA/EO or not fed with OA/EO until they reached 35 d of age. At 14 d of age, chickens received an oral suspension of two well characterized C. jejuni strains, depending on the room they were housed in. The levels of C. jejuni were periodically monitored in the caecum and on the carcasses. C. jejuni colonization was further characterized by the use of high-resolution melt analysis of the C. jejuniflaA gene （HRM-flaA）. The effect of the feed additive was strain-dependent. In room two, the feed additive had no effect on the caecal counts. In room one, at 35 d of age, caecal C. jejuni counts were higher with OA/EO, as opposed to carcasses counts which were lower in the treated group. The HRM-flaA analysis showed that an amplification profile was predominant in birds fed with OA/EO at 35 d of age in room one, suggesting the selection of a C. jejuni strain. In conclusion, the OA/EO seemed to be effective to reduce C. jejuni levels but this effect appeared strain dependent.展开更多
BACKGROUND Repeated application of the Pringle maneuver is a key obstacle to safe minimally invasive repeat liver resection(MISRLR).However,limited technical guidance is available.AIM To study the utility of newly dev...BACKGROUND Repeated application of the Pringle maneuver is a key obstacle to safe minimally invasive repeat liver resection(MISRLR).However,limited technical guidance is available.AIM To study the utility of newly developed Pringle taping method guided by liver surface in MISRLR.METHODS We retrospectively reviewed 72 cases of MISRLR performed by a single surgeon at two centers from August 2015 to July 2024.Beginning in October 2019,a liver surface-guided encirclement of hepatoduodenal ligament(LSEH)was used for repeat Pringle taping.Perioperative outcomes including Pringle taping success,operative time,blood loss,conversion rate,morbidity,and mortality were assessed.RESULTS Laparoscopic and robotic approaches were used in 63 patients and 9 patients,respectively.The median operative time,blood loss,and hospital stay were 331.5 minutes,70 mL,and 8 days,respectively.Open conversion occurred in two cases(2.8%)due to severe adhesions and right renal vein injury.Clavien-Dindo grade≥III complications occurred in 5.6%of cases with no mortality.Anti-adhesion barriers were used in 54 patients(75.0%).LSEH was attempted in 57 cases,improving Pringle taping success from 33.0%to 91.4%(P<0.001).LSEH succeeded in all patients with prior open liver resection(n=11).Among 6 patients in whom LSEH failed,3 patients(50.0%)had undergone a third liver resection,and 1 patient had a history of distal gastrectomy with choledochoduodenostomy.CONCLUSION The newly developed LSEH technique for Pringle taping in MISRLR was feasible,enhancing safety and reproducibility even in patients with a history of open liver resection.展开更多
In recent years, an increase in opportunistic fungal colonization in the oral cavity in immunocompetent patients （IC） has been observed. In the bibliography, the most observable genre is Candida and less frequently ...In recent years, an increase in opportunistic fungal colonization in the oral cavity in immunocompetent patients （IC） has been observed. In the bibliography, the most observable genre is Candida and less frequently found are other opportunistic such as Aspergillus, Rhizopus, Cryptococcus, and others. The authors determined the presence of fungi in the oral cavity of IC students, and their relationship with the concentration of secretory IgA in saliva. To this end, we collected 50 samples of oral cavity swabs, which underwent direct examination and culture in Sabouraud dextrose agar with chloramphenicol. For its identification, CHROMagar Candida and API Candida （BioMerieux） were used. We obtained nine positive cultures （7 Candida albicans and 2 Saccharomyses cerevisiae）, which represented 18% of the studied population. Throughout radial immunodiffusion （RID plates-PLATE）, we determined the concentration of secretory IgA. No relationship was observed between the colonized group and group that was not colinized. The colonization rate found is below the one described in the bibliography （30% to 50%）. However, these opportunistic fungi cause transitory colonization with no clinical relevance in IC patients and, its percentage can vary according to the studied population.展开更多
基金supported by National Institutes of Health R03DE027492 to Shareef Dabdoubsupported by National Institutes of Health,project number 7R01DE027857-06supported by National Institutes of Health R56DE033913 awarded to Purnima Kumar.
文摘Dental implants have restored masticatory function to over 100000000 individuals,yet almost 1000000 implants fail each year due to peri-implantitis,a disease triggered by peri-implant microbial dysbiosis.Our ability to prevent and treat peri-implantitis is hampered by a paucity of knowledge of how these biomes are acquired and the factors that engender normobiosis.Therefore,we combined a 3-month interventional study of 15 systemically and periodontally healthy adults with whole genome sequencing,finescale enumeration and graph theoretics to interrogate colonization dynamics in the pristine peri-implant sulcus.We discovered that colonization trajectories of implants differ substantially from adjoining teeth in acquisition of new members and development of functional synergies.Source-tracking algorithms revealed that this niche is initially seeded by bacteria trapped within the coverscrew chamber during implant placement.These pioneer species stably colonize the microbiome and exert a sustained influence on the ecosystem by serving as anchors of influential hubs and by providing functions that enable cell replication and biofilm maturation.Unlike the periodontal microbiome,recruitment of new members to the peri-implant community occurs on nepotistic principles.Maturation is accompanied by a progressive increase in anaerobiosis,however,the predominant functionalities are oxygen-dependent over the 12-weeks.The peri-implant community is easily perturbed following crown placement,but demonstrates remarkable resilience;returning to pre-perturbation states within three weeks.This study highlights important differences in the development of the periodontal and peri-implant ecosystems,and signposts the importance of placing implants in periodontally healthy individuals or following the successful resolution of periodontal disease.
基金National Natural Science Foundation of China(No.32171947 and No.31671699)which supported this research.
文摘Saline-alkali soil severely reduces the productivity of crops,including maize(Zea mays).Although several genes associated with saline-alkali tolerance have been identified in maize,the underlying regulatory mechanism remains elusive.Here,we report a direct link between colonization by arbuscular mycorrhizal fungi(AMF)and saline-alkali tolerance in maize.We identify s75,a natural maize mutant that cannot survive under moderate saline-alkali soil conditions or establish AM symbioses.The saline-alkali hypersensitive phenotype of s75 is caused by a 1340-bp deletion in Zm00001d033915,designated as ZmL75.This gene encodes a glycerol-3-phosphate acyltransferase localized in the endoplasmic reticulum,and is responsible for AMF colonization.ZmL75 expression levels in roots correspond with the root length colonization(RLC)rate during early vegetative development.Notably,the s75 mutant line shows a complete loss of AMF colonization,along with alterations in the diversity and structure of its root fungal microbiota.Conversely,overexpression of ZmL75 increases the RLC rate and enhances tolerance to saline-alkali soil conditions.These results suggest that ZmL75 is required for symbiosis with AMF,which directly improves saline-alkali tolerance.Our findings provide insights into maize-AMF interactions and offer a potential strategy for maize improvement.
文摘In the early years of the 20th century,Britain sought to compete with Russia for dominance in East Asia,and set its sights on the strategic location of Xizang.Smallpox virus epidemics have been documented in Xizang since the 7th century,and smallpox remained a major public health issue in Xizang until the early 20th century.The British colonizers learned from their experience of passing on biological science and technology in India and carried out a series of medical activities in Xizang,the most influential of which was the smallpox vaccination for the people of Gyantse and other places.This paper examines the history of the fight against smallpox in Xizang from 1900 to 1907,and studies the historical process of British colonial expansion in Xizang,as well as the interaction between the Qing government and the British invaders in medical and healthcare events such as vaccination in Xizang.
文摘Plasmid pVK1001 which carried the gfp gene of GFPmut2, a mutant of GFP, was introduced into Azospirillum brasilense Yu62 by electroporation. Maize seedlings were inoculated with the GFP-labelled baeteria and grown gnotobiotically in flask with semi-solid agar medium. Observations were performed with confocal laser scanning microscopy (CLSM) and electron microscopy, respectively, at 8 d and 12 d after inoculation. Confocal laser scanning microscopy showed that A. brasilense Yu62 could penetrate into the cortex tissue, colonizing in the intercellular spaces of the parenchyma cells of the cortex tissue. Transmission and scanning electron microscopy (TEM) showed that the majority of the bacteria colonized on the root surface and only a minority of them resided in the root interior.
基金The National Natural Science Foundation of China(32302759,32372924)the CAST Youth Talent Support Project-Special Program for Doctoral Students(156-O-230-0000375-5)。
文摘Background Weaning-induced diarrhoea and growth retardation in piglets are associated with impaired intestinal barrier function and decreased levels of colonic short-chain fatty acids(SCFAs).Although SCFA supplementation has been proposed to mitigate these issues,the efficacy and optimal dosage of sodium isobutyrate remain unclear.Results We investigated the effects of sodium isobutyrate supplementation(500,1,000,2,000,and 4,000 mg/kg diet)on weaned piglets(Duroc×Landrace×Yorkshire,28 d of age;n=8).After a 28-d feeding trial,supplementation at 500–2,000 mg/kg significantly improved average daily gain and feed efficiency and reduced diarrhoea frequency,with maximal benefits observed at 1,000 mg/kg(P<0.0001).Additionally,500–1,000 mg/kg sodium isobutyrate supplementation increased the apparent digestibility of crude protein,organic matter,and crude fibre(P<0.05).Serum biochemical parameters were unaffected,although secretory immunoglobulin A(SIgA)levels significantly increased upon supplementation with 500–1,000 mg/kg(P<0.05).16S rRNA gene sequencing indicated that sodium isobutyrate increased the abundance of beneficial colonic microbiota.The 1,000 mg/kg group presented the most pronounced effect,with a significant increase of the relative abundance of Prevotella and the greatest improvement in SCFA concentrations(P<0.05).Metabolomics revealed elevated levels of colonic indole-3-lactic acid and 3-hydroxybutyrate upon supplementation with 1,000 mg/kg(P<0.05).Transcriptomic analyses indicated activation of protein digestion and absorption pathways,and PI3K-Akt signalling,marked by TSG-6 upregulation and the suppression of ISG15 and DDIT4 expression(P<0.05).Supplementation with 1,000 mg/kg was associated with improved intestinal barrier-related markers,including reduced serum D-lactate,diamine oxidase,and lipopolysaccharide levels,increased tight junction protein expression;activation of G protein-coupled receptors;and inhibition of TLR4/MyD88/NF-κB signalling(P<0.05),suggesting enhanced barrier function.Conclusions In conclusion,dietary supplementation with 1,000 mg/kg sodium isobutyrate was associated with improved intestinal morphology,reduced serum permeability,increased expression of tight junction proteins,and enhanced immune function in weaned piglets,suggesting enhanced colonic barrier function and providing dosage guidance and mechanistic insights for future applications.
文摘The objective of this study was to evaluate the effect of a novel feed additive on chicken intestinal colonization and carcass contamination by Campylobacterjejuni. The feed additive was composed of microencapsulated organic acids and essential oils （OA/EO）. The feed additive tested was provided by Jefo Nutrition Inc., St-Hyacinthe, Quebec, Canada. Day-old birds were separated into two rooms and subdivided into two groups. Chicken were fed with OA/EO or not fed with OA/EO until they reached 35 d of age. At 14 d of age, chickens received an oral suspension of two well characterized C. jejuni strains, depending on the room they were housed in. The levels of C. jejuni were periodically monitored in the caecum and on the carcasses. C. jejuni colonization was further characterized by the use of high-resolution melt analysis of the C. jejuniflaA gene （HRM-flaA）. The effect of the feed additive was strain-dependent. In room two, the feed additive had no effect on the caecal counts. In room one, at 35 d of age, caecal C. jejuni counts were higher with OA/EO, as opposed to carcasses counts which were lower in the treated group. The HRM-flaA analysis showed that an amplification profile was predominant in birds fed with OA/EO at 35 d of age in room one, suggesting the selection of a C. jejuni strain. In conclusion, the OA/EO seemed to be effective to reduce C. jejuni levels but this effect appeared strain dependent.
文摘BACKGROUND Repeated application of the Pringle maneuver is a key obstacle to safe minimally invasive repeat liver resection(MISRLR).However,limited technical guidance is available.AIM To study the utility of newly developed Pringle taping method guided by liver surface in MISRLR.METHODS We retrospectively reviewed 72 cases of MISRLR performed by a single surgeon at two centers from August 2015 to July 2024.Beginning in October 2019,a liver surface-guided encirclement of hepatoduodenal ligament(LSEH)was used for repeat Pringle taping.Perioperative outcomes including Pringle taping success,operative time,blood loss,conversion rate,morbidity,and mortality were assessed.RESULTS Laparoscopic and robotic approaches were used in 63 patients and 9 patients,respectively.The median operative time,blood loss,and hospital stay were 331.5 minutes,70 mL,and 8 days,respectively.Open conversion occurred in two cases(2.8%)due to severe adhesions and right renal vein injury.Clavien-Dindo grade≥III complications occurred in 5.6%of cases with no mortality.Anti-adhesion barriers were used in 54 patients(75.0%).LSEH was attempted in 57 cases,improving Pringle taping success from 33.0%to 91.4%(P<0.001).LSEH succeeded in all patients with prior open liver resection(n=11).Among 6 patients in whom LSEH failed,3 patients(50.0%)had undergone a third liver resection,and 1 patient had a history of distal gastrectomy with choledochoduodenostomy.CONCLUSION The newly developed LSEH technique for Pringle taping in MISRLR was feasible,enhancing safety and reproducibility even in patients with a history of open liver resection.
文摘In recent years, an increase in opportunistic fungal colonization in the oral cavity in immunocompetent patients （IC） has been observed. In the bibliography, the most observable genre is Candida and less frequently found are other opportunistic such as Aspergillus, Rhizopus, Cryptococcus, and others. The authors determined the presence of fungi in the oral cavity of IC students, and their relationship with the concentration of secretory IgA in saliva. To this end, we collected 50 samples of oral cavity swabs, which underwent direct examination and culture in Sabouraud dextrose agar with chloramphenicol. For its identification, CHROMagar Candida and API Candida （BioMerieux） were used. We obtained nine positive cultures （7 Candida albicans and 2 Saccharomyses cerevisiae）, which represented 18% of the studied population. Throughout radial immunodiffusion （RID plates-PLATE）, we determined the concentration of secretory IgA. No relationship was observed between the colonized group and group that was not colinized. The colonization rate found is below the one described in the bibliography （30% to 50%）. However, these opportunistic fungi cause transitory colonization with no clinical relevance in IC patients and, its percentage can vary according to the studied population.
