Plantation forests play a pivotal role in carbon sequestration in terrestrial ecosystems, but enhanced nitrogen(N) deposition in these forests may affect plantation productivity by altering soil N cycling. Hence,under...Plantation forests play a pivotal role in carbon sequestration in terrestrial ecosystems, but enhanced nitrogen(N) deposition in these forests may affect plantation productivity by altering soil N cycling. Hence,understanding how simulated N deposition affects the rate and direction of soil N transformation is critically important in predicting responses of plantation productivity in the context of N loading. This study reports the effects of N addition rate(0, 40, and 120 kg N ha^(-1) a^(-1)) and form(NH_4Cl vs. NaNO_3) on net N mineralization and nitrification estimated by in situ soil core incubation and on-soil microbial biomass determined by the phospholipid fatty acid(PLFA) method in a subtropical pine plantation. N additions had no influences on net N mineralization throughout the year. Net nitrification rate was significantly reduced by additions of both NH_4Cl(71.5) and NaNO_3(47.1%) during the active growing season, with the stronger inhibitory effect at high N rates. Soil pH was markedly decreased by 0.16 units by NH_4Cl additions. N inputs significantly decreased the ratio of fungal-to-bacterial PLFAs on average by 0.28(49.1%) in November. Under NH_4Cl additions, nitrification was positively related with fungal biomass and soil pH. Under NaNO_3 additions,nitrification was positively related with all microbial groups except for bacterial biomass. We conclude that simulated N deposition inhibited net nitrification in the acidic soils of a subtropical plantation forest in China,primarily due to accelerated soil acidification and compositional shifts in microbial functional groups. These findings may facilitate a better mechanistic understanding of soil N cycling in the context of N loading.展开更多
Understanding the vertical distribution patterns of soil microbial community and its driving factors in alpine grasslands in the humid regions of the Tibet Plateau might be of great significance for predicting the soi...Understanding the vertical distribution patterns of soil microbial community and its driving factors in alpine grasslands in the humid regions of the Tibet Plateau might be of great significance for predicting the soil microbial community of this type of vegetation in response to environmental change. Using phospholipid fatty acids （PLFA）, we investigated soil microbial community composition along an elevational gradient （3094-4131 m above sea level） on Mount Yajiageng, and we explored the impact of plant functional groups and soil chemistry on the soil microbial community. Except for Arbuscular Mycorrhizal fungi （AM fungi） biomarker 18：2ω6,9 increasing significantly, other biomarkers did not show a consistent trend with the elevational gradient. Microbial biomass quantified by total PLFAs did not show the elevational trend and had mean values ranging from 1.64 to 4.09 ktmol per g organic carbon （OC）, which had the maximum value at the highest site. Bacterial PLFAs exhibited a similar trend with total PLFAs, and its mean values ranged from 0.82 to 1.81 μmol （g OC）-1. The bacterial to fungal biomass ratios had the minimum value at the highest site, which might be related to temperature and soil total nitrogen （TN）. The ratios of Gram-negative to Gram-positive bacteria had a significantly negative correlation with soil TN and had the maximum value at the highest site. Leguminous plant coverage and soil TN explained 58% of the total variation in the soil microbial community and could achieve the same interpretation as the whole model. Other factors may influence the soil microbial community through interaction with leguminous plant coverage and soil TN. Soil chemistry and plant functional group composition in substantial amounts explained different parts of the variation within the soil microbial community, and the interaction between them had no impact on the soil microbial community maybe beeause long-term grazing greatly reduces litter. In sum, although there were obvious differences in soil microbial communities along the elevation gradient, there were no clear elevational trends found in general. Plant functional groups and soil chemistry respectively affect the different aspects of soil microbial community. Leguminous plant coverage and soil TN had important effects in shaping soil microbial community.展开更多
The functional groups of planktonic protist communities and their responses to the changes of environmental conditions were investigated in a semi-enclosed shrimp-farming pond in Qingdao,Shandong Province,China,during...The functional groups of planktonic protist communities and their responses to the changes of environmental conditions were investigated in a semi-enclosed shrimp-farming pond in Qingdao,Shandong Province,China,during a six-month study period （a complete shrimp-culture cycle） from May to October 2002.The results reveal that： （1） the protist communities represented five trophic and functional groups of the species identified,about 60% were photoautotrophs,20% algivores,12% bacterivores,5% raptors and about 3% non-selectives;（2） the photoautotrophs,algivores and bacterivores were the primary contributors to the changes in the protist communities in short temporal scales,the succession of dominance typically being bacterivores→photoautotrophs→algivores,with the raptors dominating the protist communities in a single sample （early June）;（3） the photoautotrophs and non-selectives were the primary contributors to the peak of protist abundance in early October whereas the photoautotrophs,bacterivores,raptors and non-selectives mainly gave rise to two bimodal peaks of biomass in July and October respectively;（4） five functional groups of protist communities represented significant correlations with water nutrients （i.e.,NH 3-N,NO 3-N,and PO 4 ）,either alone or in combination with temperature,of which algivores and raptors were strongly correlated with phosphate and the concentration of Chl a,while bacterivores were strongly related to nitrogen and the concentration of bacteria.These findings confirm that planktonic protists are potentially useful bioindicators of water quality in the semi-enclosed mariculture system.展开更多
The objective of this study was to investigate the sulfonation of （1→6）-β-D-glucan （lasiodiplodan） as a potentiating mechanism for biological functionalities. Lasiodiplodan was sulfonated by the chlorosulfonic a...The objective of this study was to investigate the sulfonation of （1→6）-β-D-glucan （lasiodiplodan） as a potentiating mechanism for biological functionalities. Lasiodiplodan was sulfonated by the chlorosulfonic acid-pyridine method. The modified exopolysaccharide was characterized by FT-IR and 13C NMR spectroscopy, X-ray diffraction and SEM. Antioxidant activity was assessed by the methods of H2O2 and OH radical removal and reducing power. Antimicrobial potential was evaluated by the broth-microdilution method. Sulfonation resulted in a derivative with DS of 0.24. FT-IR analysis indicated the introduction of sulfonyl groups in the macromolecule structure through specific bands in the regions of 1,240 cm-1 and 810 cm-1. 13C NMR analysis suggested that sulfonation occurred at carbon 2 of the glucose residue. Sulfonation led to morphological changes in the structure of the biopolymer resulting in a heterogeneous structure with the presence of fibrils. Derivatization promoted an increase in the antioxidant ability of the macromolecule, with a high OH removal potential （74.32%）. Bacteriostatic activity against E. coli （Escherichia coli） and S. enterica （Salmonella enterica） typhimurium and fungicidal activity against C. albicans （Candida albicans） and C. tropicalis （Candida tropicalis） were found in the sulfonated sample. Sulfonation potentiated the antioxidant and antimicrobial activities of the biomacromolecule, suggesting that it is a potentiating mechanism of biological functions.展开更多
Introduction: Maternal asymptomatic colonization with GBS (Group-B Streptococcus) has become a major cause of sepsis, meningitis and encephalopathy in neonates alongside premature births, stillbirths and post-natal in...Introduction: Maternal asymptomatic colonization with GBS (Group-B Streptococcus) has become a major cause of sepsis, meningitis and encephalopathy in neonates alongside premature births, stillbirths and post-natal infections. Routine screening of pregnant women for GBS carriage and antimicrobial susceptibility are therefore necessary. This study was aimed at evaluating the prevalence, antimicrobial susceptibility pattern and factors associated with GBS colonization in pregnant women at the Regional Hospital Bamenda (RHB). Materials and Methods: Vaginal and rectal swab samples were collected from 121 pregnant women in the 3<sup>rd</sup> trimester at the RHB from December 2017 to May 2018. Sociodemographic, obstetric and neonatal history and some clinical parameters were obtained through a questionnaire approach. Cultures for the isolation and identification of GBS from the samples were done and grouping as well as susceptibility testing of GBS isolates was done. Results: The colonisation rates were 5.8% (7), 1.7% (2) and 5.8% (7) for rectal, vaginal and concomitant recto-vaginal carriage. GBS was isolated in the vagina/rectum of 16 participants (13.2% prevalence). Of the 16 GBS strains used for in vitro susceptibility test, no resistance to ampicillin, oxacillin, amoxicillin-clavulanate, ceftriaxone, erythromycin, imipenem, aztreonam and clindamycin was recorded. 6.3% (1) of the strains had intermediate susceptibility to ampicillin and amoxicillin-clavulanic acid. Of the isolates examined, 37.5% (6), and 12.5% (2) were respectively sensitive to gentamycin and levofloxacin. Maternal overweight, HIV positive status, history of PROM and spontaneous abortion, presence of Gardnerella vaginalis and Candida albicans had a high rate of GBS colonization but only HIV positive status had a statistical significance (p = 0.01). Other microbes isolated were Gardnerella vaginalis (55.4%, 67), Candida albicans (40.5%, 49), and Candida spp (12.4%, 15). Conclusion: GBS prevalence was 13.2%. GBS had decreased susceptibility to some antibiotics. Only HIV positive status was significantly associated with GBS colonization.展开更多
BACKGROUND This case series investigated the clinical manifestations,diagnoses,and treatment of cerebral abscesses caused by Streptococcus anginosus.We retrospectively analyzed the clinical characteristics and outcome...BACKGROUND This case series investigated the clinical manifestations,diagnoses,and treatment of cerebral abscesses caused by Streptococcus anginosus.We retrospectively analyzed the clinical characteristics and outcomes of three cases of cerebral abscesses caused by Streptococcus anginosus and conducted a comprehensive review of relevant literature.CASE SUMMARY Case 1 presented with a history of left otitis media and exhibited high fever,confusion,and vomiting as primary symptoms.Postoperative pus culture indicated a brain abscess caused by Streptococcus constellatus infection.Case 2 experienced dizziness for two days as the primary symptom.Postoperative pus culture suggested an intermediate streptococcal brain abscess.Case 3:Enhanced head magnetic resonance imaging(MRI)and diffusion-weighted imaging revealed occupancy of the left temporal lobe,initially suspected to be a metastatic tumor.However,a postoperative pus culture confirmed the presence of a brain abscess caused by Streptococcus anginosus infection.The three cases presented in this case series were all patients with community-acquired brain abscesses resulting from angina caused by Streptococcus group infection.All three patients demonstrated sensitivity to penicillin,ceftriaxone,vancomycin,linezolid,chloramphenicol,and levofloxacin.Successful treatment was achieved through stereotaxic puncture,drainage,and ceftriaxone administration with a six-week course of antibiotics.CONCLUSION Preoperative enhanced head MRI plays a critical role in distinguishing brain tumors from abscesses.Selecting the correct early diagnostic methods for brain abscesses and providing timely intervention are very important.This case series was in accordance with the CARE guidelines.展开更多
Pure culture and pot culture experiments were carried out to study the effect of lanthanum (La) on bacteria, actinomyces and fungus, and some microbial physiological groups , nitrifier, azotobacter and phos- phobacter...Pure culture and pot culture experiments were carried out to study the effect of lanthanum (La) on bacteria, actinomyces and fungus, and some microbial physiological groups , nitrifier, azotobacter and phos- phobacteria, in a red soil taken form the Ecological Experimental Station of Red Soil, the Chinese Academy of Sciences, Jiangxi Province. LaCl3 was added into media at levels of 0, 25, 50, 100, 150, 200, 250 and 500 mg L-1 in the pure culture experiment, and into soil samples in porcelain pots before rice growing at levels of 0, 6, 30, 150, 300, 600 and 900 mg kg-1 dry soil in the pot culture experiment. The populations of the three soil microbes in the pure culture experiment decreased with the addition level of La, indicating that La was toxic to the soil microbes in pure culture, and the sensitivity of the 3 major microbial types to La was in a decreasing order of actinomyces > bacteria > fungus. In the pot experiment, La had slightly stimulative effect on soil bacteria and actinomyces when applied at low concentrations while had inhibitory effect on soil bacteria, actinomyces and fungus at high concentrations. When the concentration of La was low, soil azotobacter was stimulated slightly while soil nitrifier was stimulated strongly and the maximum increase was up to 50%. When the concentration of La was high, both soil azotobacter and nitrifier were inhibited, and the inhibition of La to the nitrifier increased with La concentration. La added at all the levels had stimulative effect on soil inorganic and organic phosphobatteria. Among the 4 physiological groups, soil nitrifier was most sensitive to La, so , it might be reasonable to assume that soil nitrifier was a sensitive indicator for evaluating the biological and environmental effects of rare earths.展开更多
Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway ...Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway network in cluster of orthologous groups(COG)and Kyoto Encyclopedia of Genes and Genomes(KEGG),and carbohydrate-active enzymes(CAZymes)were explored in metagenomic analysis.DNA extraction from gametophytes of P.haitanensis was performed first,followed by library construction,sequencing,preprocessing of sequencing data,taxonomy assignment,gene prediction,and functional annotation.The results show that the predominant microorganisms of P.haitanensis were bacteria(98.98%),and the phylum with the highest abundance was Proteobacteria(54.64%),followed by Bacteroidetes(37.92%).Erythrobacter(3.98%)and Hyunsoonleella jejuensis(1.56%)were the genera and species with the highest abundance of bacteria,respectively.The COG annotation demonstrated that genes associated with microbial metabolism was the predominant category.The results of metabolic pathway annotation show that the ABC transport system and two-component system were the main pathways in the microbial community.Plant growth hormone biosynthesis pathway and multi-vitamin biosynthesis functional units(modules)were the other important pathways.The CAZyme annotation revealed that the starch might be an important carbon source for microorganisms.Glycosyl transferase family 2(GT2)and glycosyl transferase family 3(GT3)were the highly abundant families in glucoside transferase superfamily.Six metagenome-assembled genomes containing enzymes involved in the biosynthesis of cobalamin(vitamin B 12)and indole-3-acetic acid were obtained by binning method.They were confirmed to belong to Rhodobacterales and Rhizobiales,respectively.Our findings provide comprehensive insights into the microorganism community of Pyropia.展开更多
On basis of aquatic and riverside-aquatic plants collection of O.V. fomina botanical garden is conducted research of ontogenesis, ecology, phenology, carpogenesis, biomorphology, life forms, adaptatations, of this gr...On basis of aquatic and riverside-aquatic plants collection of O.V. fomina botanical garden is conducted research of ontogenesis, ecology, phenology, carpogenesis, biomorphology, life forms, adaptatations, of this group＇s plants, peculiarities of their cultivation and application in conditions of temperate zone of Ukraine. Special values in research have ancient genera and species, which include representatives ofNymphaeaceae salisb, and trapaceae Dumort. families, 22 species, 6 varieties, 1 hybrid, 30 cultivars of which are presented in collection of garden in open and covered soil. For the first time in covered soil of two conservatories ecological modeling was conducted. Placement of plants is done in form of 5 models of artificial ecotopes, in 155 abatises. Four ecobiomorphological groups based on rhizome system were determined for Nymphaeaceae, among which conditionally-rhizome and conditionally-stolone are provided for the first time.展开更多
基金financially supported by the Grants from the National Key Research and Development Plan(No.2016YFD06000202)the National Natural Science Foundation of China(Nos.31570443,31130009)
文摘Plantation forests play a pivotal role in carbon sequestration in terrestrial ecosystems, but enhanced nitrogen(N) deposition in these forests may affect plantation productivity by altering soil N cycling. Hence,understanding how simulated N deposition affects the rate and direction of soil N transformation is critically important in predicting responses of plantation productivity in the context of N loading. This study reports the effects of N addition rate(0, 40, and 120 kg N ha^(-1) a^(-1)) and form(NH_4Cl vs. NaNO_3) on net N mineralization and nitrification estimated by in situ soil core incubation and on-soil microbial biomass determined by the phospholipid fatty acid(PLFA) method in a subtropical pine plantation. N additions had no influences on net N mineralization throughout the year. Net nitrification rate was significantly reduced by additions of both NH_4Cl(71.5) and NaNO_3(47.1%) during the active growing season, with the stronger inhibitory effect at high N rates. Soil pH was markedly decreased by 0.16 units by NH_4Cl additions. N inputs significantly decreased the ratio of fungal-to-bacterial PLFAs on average by 0.28(49.1%) in November. Under NH_4Cl additions, nitrification was positively related with fungal biomass and soil pH. Under NaNO_3 additions,nitrification was positively related with all microbial groups except for bacterial biomass. We conclude that simulated N deposition inhibited net nitrification in the acidic soils of a subtropical plantation forest in China,primarily due to accelerated soil acidification and compositional shifts in microbial functional groups. These findings may facilitate a better mechanistic understanding of soil N cycling in the context of N loading.
基金supported by the CAS/SAFEA International Partnership Program for Creative Research Teams (KZZD-EW-TZ-06)
文摘Understanding the vertical distribution patterns of soil microbial community and its driving factors in alpine grasslands in the humid regions of the Tibet Plateau might be of great significance for predicting the soil microbial community of this type of vegetation in response to environmental change. Using phospholipid fatty acids （PLFA）, we investigated soil microbial community composition along an elevational gradient （3094-4131 m above sea level） on Mount Yajiageng, and we explored the impact of plant functional groups and soil chemistry on the soil microbial community. Except for Arbuscular Mycorrhizal fungi （AM fungi） biomarker 18：2ω6,9 increasing significantly, other biomarkers did not show a consistent trend with the elevational gradient. Microbial biomass quantified by total PLFAs did not show the elevational trend and had mean values ranging from 1.64 to 4.09 ktmol per g organic carbon （OC）, which had the maximum value at the highest site. Bacterial PLFAs exhibited a similar trend with total PLFAs, and its mean values ranged from 0.82 to 1.81 μmol （g OC）-1. The bacterial to fungal biomass ratios had the minimum value at the highest site, which might be related to temperature and soil total nitrogen （TN）. The ratios of Gram-negative to Gram-positive bacteria had a significantly negative correlation with soil TN and had the maximum value at the highest site. Leguminous plant coverage and soil TN explained 58% of the total variation in the soil microbial community and could achieve the same interpretation as the whole model. Other factors may influence the soil microbial community through interaction with leguminous plant coverage and soil TN. Soil chemistry and plant functional group composition in substantial amounts explained different parts of the variation within the soil microbial community, and the interaction between them had no impact on the soil microbial community maybe beeause long-term grazing greatly reduces litter. In sum, although there were obvious differences in soil microbial communities along the elevation gradient, there were no clear elevational trends found in general. Plant functional groups and soil chemistry respectively affect the different aspects of soil microbial community. Leguminous plant coverage and soil TN had important effects in shaping soil microbial community.
基金The National Natural Science Foundation of China under contract Nos 40676076 and 30700069the Darwin Initiative Programme under contract No.14-015a grant from the Center of Excellence in Biodiversity Research,King Saud University
文摘The functional groups of planktonic protist communities and their responses to the changes of environmental conditions were investigated in a semi-enclosed shrimp-farming pond in Qingdao,Shandong Province,China,during a six-month study period （a complete shrimp-culture cycle） from May to October 2002.The results reveal that： （1） the protist communities represented five trophic and functional groups of the species identified,about 60% were photoautotrophs,20% algivores,12% bacterivores,5% raptors and about 3% non-selectives;（2） the photoautotrophs,algivores and bacterivores were the primary contributors to the changes in the protist communities in short temporal scales,the succession of dominance typically being bacterivores→photoautotrophs→algivores,with the raptors dominating the protist communities in a single sample （early June）;（3） the photoautotrophs and non-selectives were the primary contributors to the peak of protist abundance in early October whereas the photoautotrophs,bacterivores,raptors and non-selectives mainly gave rise to two bimodal peaks of biomass in July and October respectively;（4） five functional groups of protist communities represented significant correlations with water nutrients （i.e.,NH 3-N,NO 3-N,and PO 4 ）,either alone or in combination with temperature,of which algivores and raptors were strongly correlated with phosphate and the concentration of Chl a,while bacterivores were strongly related to nitrogen and the concentration of bacteria.These findings confirm that planktonic protists are potentially useful bioindicators of water quality in the semi-enclosed mariculture system.
文摘The objective of this study was to investigate the sulfonation of （1→6）-β-D-glucan （lasiodiplodan） as a potentiating mechanism for biological functionalities. Lasiodiplodan was sulfonated by the chlorosulfonic acid-pyridine method. The modified exopolysaccharide was characterized by FT-IR and 13C NMR spectroscopy, X-ray diffraction and SEM. Antioxidant activity was assessed by the methods of H2O2 and OH radical removal and reducing power. Antimicrobial potential was evaluated by the broth-microdilution method. Sulfonation resulted in a derivative with DS of 0.24. FT-IR analysis indicated the introduction of sulfonyl groups in the macromolecule structure through specific bands in the regions of 1,240 cm-1 and 810 cm-1. 13C NMR analysis suggested that sulfonation occurred at carbon 2 of the glucose residue. Sulfonation led to morphological changes in the structure of the biopolymer resulting in a heterogeneous structure with the presence of fibrils. Derivatization promoted an increase in the antioxidant ability of the macromolecule, with a high OH removal potential （74.32%）. Bacteriostatic activity against E. coli （Escherichia coli） and S. enterica （Salmonella enterica） typhimurium and fungicidal activity against C. albicans （Candida albicans） and C. tropicalis （Candida tropicalis） were found in the sulfonated sample. Sulfonation potentiated the antioxidant and antimicrobial activities of the biomacromolecule, suggesting that it is a potentiating mechanism of biological functions.
文摘Introduction: Maternal asymptomatic colonization with GBS (Group-B Streptococcus) has become a major cause of sepsis, meningitis and encephalopathy in neonates alongside premature births, stillbirths and post-natal infections. Routine screening of pregnant women for GBS carriage and antimicrobial susceptibility are therefore necessary. This study was aimed at evaluating the prevalence, antimicrobial susceptibility pattern and factors associated with GBS colonization in pregnant women at the Regional Hospital Bamenda (RHB). Materials and Methods: Vaginal and rectal swab samples were collected from 121 pregnant women in the 3<sup>rd</sup> trimester at the RHB from December 2017 to May 2018. Sociodemographic, obstetric and neonatal history and some clinical parameters were obtained through a questionnaire approach. Cultures for the isolation and identification of GBS from the samples were done and grouping as well as susceptibility testing of GBS isolates was done. Results: The colonisation rates were 5.8% (7), 1.7% (2) and 5.8% (7) for rectal, vaginal and concomitant recto-vaginal carriage. GBS was isolated in the vagina/rectum of 16 participants (13.2% prevalence). Of the 16 GBS strains used for in vitro susceptibility test, no resistance to ampicillin, oxacillin, amoxicillin-clavulanate, ceftriaxone, erythromycin, imipenem, aztreonam and clindamycin was recorded. 6.3% (1) of the strains had intermediate susceptibility to ampicillin and amoxicillin-clavulanic acid. Of the isolates examined, 37.5% (6), and 12.5% (2) were respectively sensitive to gentamycin and levofloxacin. Maternal overweight, HIV positive status, history of PROM and spontaneous abortion, presence of Gardnerella vaginalis and Candida albicans had a high rate of GBS colonization but only HIV positive status had a statistical significance (p = 0.01). Other microbes isolated were Gardnerella vaginalis (55.4%, 67), Candida albicans (40.5%, 49), and Candida spp (12.4%, 15). Conclusion: GBS prevalence was 13.2%. GBS had decreased susceptibility to some antibiotics. Only HIV positive status was significantly associated with GBS colonization.
基金Supported by 2024 Zhejiang Province Traditional Chinese Medicine Science and Technology Plan,No.2024ZL1129,No.2024ZL1130.
文摘BACKGROUND This case series investigated the clinical manifestations,diagnoses,and treatment of cerebral abscesses caused by Streptococcus anginosus.We retrospectively analyzed the clinical characteristics and outcomes of three cases of cerebral abscesses caused by Streptococcus anginosus and conducted a comprehensive review of relevant literature.CASE SUMMARY Case 1 presented with a history of left otitis media and exhibited high fever,confusion,and vomiting as primary symptoms.Postoperative pus culture indicated a brain abscess caused by Streptococcus constellatus infection.Case 2 experienced dizziness for two days as the primary symptom.Postoperative pus culture suggested an intermediate streptococcal brain abscess.Case 3:Enhanced head magnetic resonance imaging(MRI)and diffusion-weighted imaging revealed occupancy of the left temporal lobe,initially suspected to be a metastatic tumor.However,a postoperative pus culture confirmed the presence of a brain abscess caused by Streptococcus anginosus infection.The three cases presented in this case series were all patients with community-acquired brain abscesses resulting from angina caused by Streptococcus group infection.All three patients demonstrated sensitivity to penicillin,ceftriaxone,vancomycin,linezolid,chloramphenicol,and levofloxacin.Successful treatment was achieved through stereotaxic puncture,drainage,and ceftriaxone administration with a six-week course of antibiotics.CONCLUSION Preoperative enhanced head MRI plays a critical role in distinguishing brain tumors from abscesses.Selecting the correct early diagnostic methods for brain abscesses and providing timely intervention are very important.This case series was in accordance with the CARE guidelines.
基金Project (No. 29890282) supported by the National Natural Science Foundation of China.
文摘Pure culture and pot culture experiments were carried out to study the effect of lanthanum (La) on bacteria, actinomyces and fungus, and some microbial physiological groups , nitrifier, azotobacter and phos- phobacteria, in a red soil taken form the Ecological Experimental Station of Red Soil, the Chinese Academy of Sciences, Jiangxi Province. LaCl3 was added into media at levels of 0, 25, 50, 100, 150, 200, 250 and 500 mg L-1 in the pure culture experiment, and into soil samples in porcelain pots before rice growing at levels of 0, 6, 30, 150, 300, 600 and 900 mg kg-1 dry soil in the pot culture experiment. The populations of the three soil microbes in the pure culture experiment decreased with the addition level of La, indicating that La was toxic to the soil microbes in pure culture, and the sensitivity of the 3 major microbial types to La was in a decreasing order of actinomyces > bacteria > fungus. In the pot experiment, La had slightly stimulative effect on soil bacteria and actinomyces when applied at low concentrations while had inhibitory effect on soil bacteria, actinomyces and fungus at high concentrations. When the concentration of La was low, soil azotobacter was stimulated slightly while soil nitrifier was stimulated strongly and the maximum increase was up to 50%. When the concentration of La was high, both soil azotobacter and nitrifier were inhibited, and the inhibition of La to the nitrifier increased with La concentration. La added at all the levels had stimulative effect on soil inorganic and organic phosphobatteria. Among the 4 physiological groups, soil nitrifier was most sensitive to La, so , it might be reasonable to assume that soil nitrifier was a sensitive indicator for evaluating the biological and environmental effects of rare earths.
基金Supported by the National Key R&D Program of China(Nos.2018YFC1406704,2018YFD0900106,2018YFC1406700)the Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.2018SDKJ0302-4)the MOA Modern Agricultural Talents Support Project。
文摘Microorganisms plays an important role in the growth of Pyropia haitanensis.To understand the structural and functional diversity of the microorganism community of P.haitanensis(PH40),the associated metabolic pathway network in cluster of orthologous groups(COG)and Kyoto Encyclopedia of Genes and Genomes(KEGG),and carbohydrate-active enzymes(CAZymes)were explored in metagenomic analysis.DNA extraction from gametophytes of P.haitanensis was performed first,followed by library construction,sequencing,preprocessing of sequencing data,taxonomy assignment,gene prediction,and functional annotation.The results show that the predominant microorganisms of P.haitanensis were bacteria(98.98%),and the phylum with the highest abundance was Proteobacteria(54.64%),followed by Bacteroidetes(37.92%).Erythrobacter(3.98%)and Hyunsoonleella jejuensis(1.56%)were the genera and species with the highest abundance of bacteria,respectively.The COG annotation demonstrated that genes associated with microbial metabolism was the predominant category.The results of metabolic pathway annotation show that the ABC transport system and two-component system were the main pathways in the microbial community.Plant growth hormone biosynthesis pathway and multi-vitamin biosynthesis functional units(modules)were the other important pathways.The CAZyme annotation revealed that the starch might be an important carbon source for microorganisms.Glycosyl transferase family 2(GT2)and glycosyl transferase family 3(GT3)were the highly abundant families in glucoside transferase superfamily.Six metagenome-assembled genomes containing enzymes involved in the biosynthesis of cobalamin(vitamin B 12)and indole-3-acetic acid were obtained by binning method.They were confirmed to belong to Rhodobacterales and Rhizobiales,respectively.Our findings provide comprehensive insights into the microorganism community of Pyropia.
文摘On basis of aquatic and riverside-aquatic plants collection of O.V. fomina botanical garden is conducted research of ontogenesis, ecology, phenology, carpogenesis, biomorphology, life forms, adaptatations, of this group＇s plants, peculiarities of their cultivation and application in conditions of temperate zone of Ukraine. Special values in research have ancient genera and species, which include representatives ofNymphaeaceae salisb, and trapaceae Dumort. families, 22 species, 6 varieties, 1 hybrid, 30 cultivars of which are presented in collection of garden in open and covered soil. For the first time in covered soil of two conservatories ecological modeling was conducted. Placement of plants is done in form of 5 models of artificial ecotopes, in 155 abatises. Four ecobiomorphological groups based on rhizome system were determined for Nymphaeaceae, among which conditionally-rhizome and conditionally-stolone are provided for the first time.
