Group B Streptococcus(GBS;Streptococcus agalactiae)is a gram-positive coccus that colonizes the gastrointestinal and genital tracts in adults,as well as the upper respiratory tract in infants.While it has been thought...Group B Streptococcus(GBS;Streptococcus agalactiae)is a gram-positive coccus that colonizes the gastrointestinal and genital tracts in adults,as well as the upper respiratory tract in infants.While it has been thought that GBS only results in invasive disease in pregnant females and neonates,recent literature has suggested an increasing incidence of invasive GBS among non-pregnant individuals within the United States.展开更多
BACKGROUND Pericarditis is the inflammation of the pericardial sac due to a variety of stimuli that ultimately trigger a stereotyped immune response.This condition accounts for up to 5%of emergency department visits f...BACKGROUND Pericarditis is the inflammation of the pericardial sac due to a variety of stimuli that ultimately trigger a stereotyped immune response.This condition accounts for up to 5%of emergency department visits for nonischemic chest pain in Western Europe and North America.The most common symptoms of clinical presentation are chest pain and shortness of breath with associated unique electrocardiographic changes.Acute pericarditis is generally self-limited.However,some cases may be complicated by either tamponade or a large pericardial effusion,which carries a significant risk of recurrence.Risk factors for acute pericarditis include viral infections,cardiac surgery,and autoimmune disorders.A rarer cause of pericardial inflammation includes pneumonia,which can induce purulent pericarditis that has been increasingly rare since the advent of antibiotics.Purulent pericarditis carries a high fatality rate,especially in the setting of tamponade,and is invariably deadly without the administration of antibiotics.Bedside transthoracic echocardiogram is a quick and helpful method that can aid in the diagnosis and management.CASE SUMMARY We present the case of a 62-year-old woman who sought medical attention at the emergency department(ED)due to a 5-day history of chest pain,shortness of breath,and subjective fevers.Laboratory findings in the ED were significant for leukocytosis and elevated erythrocyte sedimentation rate and C-reactive protein.A chest X-ray revealed a new focal density within the left lower lung base,and a bedside point-of-care ultrasound showed a pericardial fluid collection.The patient was subsequently admitted,where she underwent pericardiocentesis.Fluid cultures from drainage grew streptococcus pneumoniae.She was started on broadspectrum antibiotics immediately after the procedure.The patient was ultimately discharged in stable condition with cardiology and infectious disease follow-up.CONCLUSION This case report emphasizes a unique complication of community-acquired pneumonia.Purulent pericarditis due to streptococcus pneumonia occurs via intrathoracic spread of the organism to the pericardium.This condition is virtually fatal without the administration of antibiotics.Therefore,in the context of suspected pneumonia and a new pericardial fluid collection on imaging,clinicians should suspect purulent pericarditis until proven otherwise,which requires emergent intervention.展开更多
In the realm of medical rarity,the convergence of infective endocarditis with the development of an aortic root abscess stands as a formidable challenge,often bearing a grim prognosis.Recognizing this perilous conditi...In the realm of medical rarity,the convergence of infective endocarditis with the development of an aortic root abscess stands as a formidable challenge,often bearing a grim prognosis.Recognizing this perilous condition requires a vigilant eye.Embolic events stemming from infective endocarditis can precipitate acute coronary syndrome,adding another layer of complexity to diagnosis and treatment.展开更多
Toxin–antitoxin(TA)systems,which are prevalent in bacteria and archaea,play diverse roles in bacterial physiology and have been proposed to be significant in stress adaptation.Despite the extensive characterization o...Toxin–antitoxin(TA)systems,which are prevalent in bacteria and archaea,play diverse roles in bacterial physiology and have been proposed to be significant in stress adaptation.Despite the extensive characterization of numerous TA systems in various bacteria,the investigation of these systems within Streptococcus suis is still limited.Here,we systematically analyzed the type Ⅱ TA systems of 95 S.suis genomes available in the GenBank database using TAfinder.A total of 612 putative type Ⅱ TA systems were retrieved and classified into 10 categories by phylogenetic analysis.Notably,an elevated occurrence of these TA systems was observed among the important prevalent serotypes 2,4,5,9,14,Chz,NCL1,and NCL3 strains.The following study identified the activities of TA systems using 2 strategies and confirmed the regulatory effect of HigBA on the type Ⅶ secretion system in S.suis by measuringβ-galactosidase activity and transcriptional changes.Moreover,we unveiled a hitherto uncharacterized,highly prevalent novel TA system,with the composition of antitoxin–toxin–antitoxin(SS-ATA),which regulates the downstream two-component signaling system.Altogether,this study systematically analyzed the type Ⅱ TA systems within S.suis,highlighting the widespread distribution of Hig BA and SS-ATA as important regulatory elements in S.suis.展开更多
BACKGROUND The Streptococcus salivarius(S.salivarius)group,which produces the enzyme urease has been identified as a potential contributor to ammonia production in the gut.Researchers have reported that patients with ...BACKGROUND The Streptococcus salivarius(S.salivarius)group,which produces the enzyme urease has been identified as a potential contributor to ammonia production in the gut.Researchers have reported that patients with minimal HE had an increased abundance of the S.salivarius group,which is a specific change in the gut microbiota that distinguishes them from healthy individuals.The correlation between the aggregation of specific bacterial species and fibrosis progression in chronic liver disease(CLD)is yet to be fully elucidated.AIM To quantify S.salivarius using digital PCR(dPCR)as a liver fibrosis marker of CLD.METHODS This study retrospectively analysed 52 patients with CLD.To quantify S.salivarius in patients with CLD using dPCR,we evaluated the specificity and sensitivity of S.salivarius bacterial load using dPCR for a type strain.Next,we evaluated the clinical usefulness of dPCR for S.salivarius load quantification for detecting liver fibrosis in patients with CLD.The liver fibrosis stage was categorized into mild and advanced fibrosis based on pathological findings.RESULTS The dPCR assay revealed that S.salivarius was highly positive for the tnpA gene.The lower limit of quantification for dPCR using the tnpA gene with a 1μL template comprising 1.28×102 CFU/mL was 4.3 copies.After considering the detection range in dPCR,we adjusted the extracted DNA concentration to 5.0×10-4 ng/μL from 200 mg stool samples.The median bacterial loads of S.salivarius in stool sample from patients with mild and advanced fibrosis were 1.9 and 7.4 copies/μL,respectively.The quantification of S.salivarius load was observed more frequently in patients with advanced fibrosis than in those with mild fibrosis(P=0.032).CONCLUSION Quantifying of S.salivarius load using digital PCR is a useful biomarker for liver fibrosis in patients with CLD.展开更多
Streptococcus (S.) pyogenes is usually associated with mild infections of the pharynx and skin.However,in some cases,this microorganism can cause potentially lethal invasive infections,such as bacteremic pneumonia,ski...Streptococcus (S.) pyogenes is usually associated with mild infections of the pharynx and skin.However,in some cases,this microorganism can cause potentially lethal invasive infections,such as bacteremic pneumonia,skin and soft-tissue infections,sepsis,meningitis,necrotizing fasciitis,and streptococcal toxic shock syndrome.^([1,2])Although S.pyogenes is currently considered a rare cause of pneumonia,with most cases occurring in patients following influenza,the mortality rate for invasive infections is high.^([3,4])We present a case of S.pyogenes bacteremic pneumonia in a woman with no severe comorbidities,which led to a fatal outcome 9h after admission to the hospital on the third day of the disease onset.展开更多
Streptococcus thermophilus is one of the most prevalent species in stool samples of westernized populations due to continuous exposure to fermented dairy products.However,few studies have explored the effect on host p...Streptococcus thermophilus is one of the most prevalent species in stool samples of westernized populations due to continuous exposure to fermented dairy products.However,few studies have explored the effect on host physiology by multiple S.thermophilus strains and considered the inter-strain differences in regulating host.In the present study,we investigated how four S.thermophilus strains influenced the gut microbiota,mucin changes,and host metabolism after 28 days of intervention in conventional mice.The results indicated that the consumption of S.thermophilus affected the host with strain specificity.Among four S.thermophilus strains,DYNDL13-4 and DQHXNQ38M61,especially DQHXNQ38M61,had more effect on host physiology by modulating gut microbiota and host metabolism than LMD9 and 4M6.Ingestion of strains DYNDL13-4 and DQHXNQ38M61 resulted in more remarkable changes in amino acid metabolism and lipid metabolism than that of strains LMD9 and 4M6,which may be related to the elevation of intestinal Bifidobacterium by DYNDL13-4 and DQHXNQ38M61.The enriched Coriobacteriaceae UCG-002,Rikenellaceae RC9 gut group,and Lactobacillus only in the DQHXNQ38M61 group,had a close relationship with the prominent effect of DQHXNQ38M61 on regulating amino acid and lipid metabolism.In addition,DQHXNQ38M61 had a strong influence on degrading colonic mucin fucose by decreasedα-fucosidase activity in feces,and improving mucin sulfation by upregulated Gal3ST2 expression.Comparative genomic analysis revealed that the four S.thermophilus strains belonged to different branches in the phylogenetic tree,and DYNDL13-4 and DQHXNQ38M61 had more genes involved in carbohydrate metabolism,amino acid metabolism,membrane transport,and signal transduction,which may confer the capacity of nutrient utilization and gastrointestinal adaptation of the strains and be associated with their strong regulation in host.Our study provides valuable information for understanding the regulation of host metabolism after consuming different S.thermophilus strains and could facilitate potential personalized applications of S.thermophilus based on strain varieties.展开更多
The microbiota is strongly association with cancer.Studies have shown significant differences in the gastric microbiota between patients with gastric cancer(GC)patients and noncancer patients,suggesting that the micro...The microbiota is strongly association with cancer.Studies have shown significant differences in the gastric microbiota between patients with gastric cancer(GC)patients and noncancer patients,suggesting that the microbiota may play a role in the development of GC.Although Helicobacter pylori(H.pylori)infection is widely recognized as a primary risk factor for GC,recent studies based on microbiota sequencing technology have revealed that non-H.pylori microbes also have a significant impact on GC.A recent study discovered that Streptococcus anginosus(S.anginosus)is more prevalent in the gastric mucosa of patients with GC than in that of those without GC.S.anginosus infection can spontaneously induce chronic gastritis,mural cell atrophy,mucoid chemotaxis,and heterotrophic hyperplasia,which promote the development of precancerous lesions of GC(PLGC).S.anginosus also disrupts the gastric barrier function,promotes the proliferation of GC cells,and inhibits apoptosis.However,S.anginosus is underrepresented in the literature.Recent reports suggest that it may cause precancerous lesions,indicating its emerging pathogenicity.Modern novel molecular diagnostic techniques,such as polymerase chain reaction,genetic testing,and Ultrasensitive Chromosomal Aneuploidy Detection,can be used to gastric precancerous lesions via microbial markers.Therefore,we present a concise summary of the relationship between S.anginosus and PLGC.Our aim was to further investigate new methods of preventing and treating PLGC by exploring the pathogenicity of S.anginosus on PLGC.展开更多
Streptococcus suis serotype 2(S.suis 2)is a zoonotic pathogen that clinically causes severe swine and human infections(such as meningitis,endocarditis,and septicemia).In order to cause widespread diseases in different...Streptococcus suis serotype 2(S.suis 2)is a zoonotic pathogen that clinically causes severe swine and human infections(such as meningitis,endocarditis,and septicemia).In order to cause widespread diseases in different organs,S.suis 2 must colonize the host,break the blood barrier,and cause exaggerated inflammation.In the last few years,most studies have focused on a single virulence factor and its influences on the host.Membrane vesicles(MVs)can be actively secreted into the extracellular environment contributing to bacteria-host interactions.Gram-negative bacteria-derived outer membrane vesicles(OMVs)were recently shown to activate host Caspase-11-mediated non-canonical inflammasome pathway via deliverance of OMV-bound lipopolysaccharide(LPS),causing host cell pyroptosis.However,little is known about the effect of the MVs from S.suis 2(Gram-positive bacteria without LPS)on cell pyroptosis.Thus,we investigated the molecular mechanism by which S.suis 2 MVs participate in endothelial cell pyroptosis.In this study,we used proteomics,electron scanning microscopy,fluorescence microscope,Western blotting,and bioassays,to investigate the MVs secreted by S.suis 2.First,we demonstrated that S.suis 2 secreted MVs with an average diameter of 72.04 nm,and 200 proteins in MVs were identified.Then,we showed that MVs were transported to cells via mainly dynamin-dependent endocytosis.The S.suis 2 MVs activated NLRP3/Caspase-1/GSDMD canonical inflammasome signaling pathway,resulting in cell pyroptosis,but it did not activate the Caspase-4/-5 pathway.More importantly,endothelial cells produce large amounts of reactive oxygen species(ROS)and lost their mitochondrial membrane potential under induction by S.suis 2 MVs.The results in this study suggest for the first time that MVs from S.suis 2 were internalized by endothelial cells via mainly dynamin-dependent endocytosis and might promote NLRP3/Caspase-1/GSDMD pathway by mitochondrial damage,which produced mtDNA and ROS under induction,leading to the pyroptosis of endothelial cells.展开更多
Objective:To address the lack of research on invasive group B Streptococcus(GBS)infections in Malaysia and Southeast Asia through a comprehensive analysis of GBS isolates obtained from hospitals.Methods:Medical record...Objective:To address the lack of research on invasive group B Streptococcus(GBS)infections in Malaysia and Southeast Asia through a comprehensive analysis of GBS isolates obtained from hospitals.Methods:Medical records from patients with GBS infection isolated from the sterile site,such as blood and cerebrospinal fluid from 14 July 2019 to 15 December 2020,were reviewed from six major hospitals in Peninsular Malaysia.Inclusion criteria were invasive GBS,sterile sites and non-repeated GBS isolated from the same patients in the same admission.Viable isolates were re-identified for GBS and serotyped.Results:A total of 118 patients were eligible,with a majority of non-pregnant adults(76.3%).Over half of the patients(62.7%)had underlying medical conditions,with diabetes as the most common disease,followed by respiratory disease,renal disease,cardiovascular disease and skin and soft tissue disease.The most common manifestations were sepsis,followed by soft tissue abscess,diabetic foot ulcer,wet gangrene and cellulitis.The overall mortality was 7.6%.The most common serotype was serotype桋.Conclusions:Invasive GBS infection among non-pregnant adults showed a rising trend,particularly among diabetic individuals.The study underscores the importance of reducing risk factors and highlights the necessity of developing GBS vaccination as a preventive strategy for both infants and adults.展开更多
BACKGROUND:Streptococcus pneumoniae(S.pneumoniae)is a common pathogen that causes bacterial pneumonia.However,with increasing bacterial resistance,there is an urgent need to develop new drugs to treat S.pneumoniae inf...BACKGROUND:Streptococcus pneumoniae(S.pneumoniae)is a common pathogen that causes bacterial pneumonia.However,with increasing bacterial resistance,there is an urgent need to develop new drugs to treat S.pneumoniae infections.Nanodefensin with a 14-carbon saturated fatty acid(ND-C14)is a novel nanoantimicrobial peptide designed by modifying myristic acid at the C-terminus of humanα-defensin 5(HD5)via an amide bond.However,it is unclear whether ND-C14 is effective against lung infections caused by S.pneumoniae.METHODS:In vitro,three groups were established,including the control group,and the HD5 and ND-C14 treatment groups.A virtual colony-count assay was used to evaluate the antibacterial activity of HD5 and ND-C14 against S.pneumoniae.The morphological changes of S.pneumoniae treated with HD5 or ND-C14 were observed by scanning electron microscopy.In vivo,mice were divided into sham,vehicle,and ND-C14 treatment groups.Mice in the sham group were treated with 25μL of phosphate-buffered saline(PBS).Mice in the vehicle and ND-C14 treatment groups were treated with intratracheal instillation of 25μL of bacterial suspension with 2×108 CFU/mL(total bacterial count:5×10^(6) CFU),and then the mice were given 25μL PBS or intratracheally injected with 25μL of ND-C14(including 20μg or 50μg),respectively.Survival rates were evaluated in the vehicle and ND-C14 treatment groups.Bacterial burden in the blood and bronchoalveolar lavage fluid were counted.The lung histology of the mice was assessed.A propidium iodide uptake assay was used to clarify the destructive eff ect of ND-C14 against S.pneumoniae.RESULTS:Compared with HD5,ND-C14 had a better bactericidal eff ect against S.pneumoniae because of its stronger ability to destroy the membrane structure of S.pneumoniae in vitro.In vivo,ND-C14 significantly delayed the death time and improved the survival rate of mice infected with S.pneumoniae.ND-C14 reduced bacterial burden and lung tissue injury.Moreover,ND-C14 had a membrane permeation eff ect on S.pneumoniae,and its destructive ability increased with increasing ND-C14 concentration.CONCLUSION:The ND-C14 may improve bactericidal eff ects on S.pneumoniae both in vitro and in vivo.展开更多
BACKGROUND Streptococcus gallolyticus subspecies pasteurianus(SGSP)is a rare pathogen responsible for infant sepsis and meningitis and is potentially overlooked because it is not included in routine group B streptococ...BACKGROUND Streptococcus gallolyticus subspecies pasteurianus(SGSP)is a rare pathogen responsible for infant sepsis and meningitis and is potentially overlooked because it is not included in routine group B streptococcal screenings.Hence,we present a case of SGSP-induced infant meningitis and sepsis,accompanied by bronchopneumonia induced by multidrug-resistant Staphylococcus aureus(MRSA),providing insights into the identification,management,and prognosis of this bacterial infection.CASE SUMMARY A 45-day-old female infant presented with two episodes of high fever(maximum temperature:39.5°C)and two generalized grand mal seizure episodes that lasted over ten seconds and self-resolved without concomitant symptoms.Postadmission,the patient’s C-reactive protein level was 40.73 mg/L,white blood cell count was 13.42×10^(9)/L,neutrophil ratio was 78.4%,procalcitonin level was 7.89μg/L,cerebrospinal fluid(CSF)white cell count was 36×10^(6)/L,multinucleated cell ratio was 95.2%,and protein concentration was 0.41 g/L.Blood and CSF culture revealed that the pathogen was SGSP.The bacterium was sensitive to ampicillin,furazolidone,penicillin,lincomycin,moxifloxacin,rifampicin,vancomycin,and levofloxacin but resistant to clindamycin and tetracycline.Sputum culture revealed the presence of MRSA,which was sensitive to vancomycin.The patient was diagnosed with meningitis and sepsis caused by SGSP,accompanied by bronchopneumonia induced by MRSA.Ceftriaxone(100 mg/kg/d)combined with vancomycin(10 mg/kg/dose,q6h)was given as an anti-infective treatment postadmission.After 12 days of treatment,the infant was discharged from the hospital with normal CSF,blood culture,and routine blood test results,and no complications,such as subdural effusion,were observed on cranial computed tomography.No growth retardation or neurological sequelae occurred during follow-up.CONCLUSION SGPSP-induced infant bacterial meningitis and sepsis should be treated with prompt blood and CSF cultures,and a sensitive antibiotic therapy to ensure a favorable prognosis.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
Rationale:Acute otitis media is a common disease in early childhood,and is usually caused by Streptococcus pneumoniae(S.pneumoniae).Acute mastoiditis is a complication of acute otitis media and can involve not only th...Rationale:Acute otitis media is a common disease in early childhood,and is usually caused by Streptococcus pneumoniae(S.pneumoniae).Acute mastoiditis is a complication of acute otitis media and can involve not only the mucoperiosteum of the middle ear but can also spread to the periosteum by destroying the mastoid bone(acute coalescent mastoiditis).In addition,the infection can extend through the surrounding bones or the emissary veins beyond the mastoid’s air cells,leading to subperiosteal abscesses.Patient’s Concern:A 16-month-old female patient was hospitalized due to the purulent discharge of the left ear and the symptoms of right mastoiditis(swelling and redness of the skin).Diagnosis:Bilateral acute coalescent mastoiditis caused by S.pneumoniae infection.The computer tomography revealed bilateral bone destruction of the mastoid and abscesses found behind the auricle on both sides.Interventions:The patient underwent intravenous antibiotic therapy and surgical treatment.Outcomes:The patient was discharged 14 days after hospitalization with an improved condition.Lessons:Improperly treated acute coalescent mastoiditis can lead to extracranial and intracranial complications,sometimes serious and even life-threatening.Complications are prevalent in children under 2 years,in whom the disease progresses more rapidly and severely.The vaccination with a 13-valent vaccine may not result in sufficient immunity against S.pneumoniae,a predominant pathogen in children affected by acute coalescent mastoiditis.展开更多
BACKGROUND Lung abscess found on chest X-ray and computed tomography examinations is rare in infants and young children.Several pathogens can cause lung abscesses,with the most common pathogens being anaerobes,Strepto...BACKGROUND Lung abscess found on chest X-ray and computed tomography examinations is rare in infants and young children.Several pathogens can cause lung abscesses,with the most common pathogens being anaerobes,Streptococci and Staphylococcus aureus.Streptococcus pseudopneumoniae(S.pseudopneumoniae)is a member of the Streptococcaceae family,and is mainly isolated from respiratory tract specimens.There are currently no cases of lung abscess caused by S.pseudopneumoniae in the literature.CASE SUMMARY A 2-year-old boy was admitted to hospital due to persistent cough and fever.Lung computed tomography examination suggested the formation of a lung abscess.His diagnosis was not confirmed by testing for serum respiratory pathogens(6 items),respiratory pathogen nucleic acid(27 items),and laboratory culture.Finally,metagenomic next-generation sequencing of bronchoalveolar lavage fluid revealed the presence of S.pseudopneumoniae,confirming its role in causing the lung abscess.After receiving antibiotic treatment,reexamination with lung computed tomography showed that the abscess was resorbed and the patient’s outcome was good.CONCLUSION This is the first report of a lung abscess in a child caused by S.pseudopneumoniae infection.Metagenomic next-generation sequencing of bronchoalveolar lavage fluid is helpful in achieving rapid and accurate pathogen identification.展开更多
BACKGROUND The oral cavity harbors more than 700 species of bacteria,which play crucial roles in the development of various oral diseases including caries,endodontic infection,periodontal infection,and diverse oral di...BACKGROUND The oral cavity harbors more than 700 species of bacteria,which play crucial roles in the development of various oral diseases including caries,endodontic infection,periodontal infection,and diverse oral diseases.AIM To investigate the antimicrobial action of Cymbopogon Schoenanthus and Pelargonium graveolens essential oils against Streptococcus mutans,Staphylococcus aureus,Candida albicans,Ca.dubliniensis,and Ca.krusei.METHODS Minimum microbicidal concentration was determined following Clinical and Laboratory Standards Institute documents.The synergistic antimicrobial activity was evaluated using the Broth microdilution checkerboard method,and the antibiofilm activity was evaluated with the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay.Data were analyzed by one-way analysis of variance followed by the Tukey post-hoc test(P≤0.05).RESULTS C.schoenanthus and P.graveolens essential oils were as effective as 0.12%chlorhexidine against S.mutans and St.aureus monotypic biofilms after 24 h.After 24 h P.graveolens essential oil at 0.25%was more effective than the nystatin group,and C.schoenanthus essential oil at 0.25%was as effective as the nystatin group.CONCLUSION C.schoenanthus and P.graveolens essential oils are effective against S.mutans,St.aureus,Ca.albicans,Ca.dubliniensis,and Ca.krusei at different concentrations after 5 min and 24 h.展开更多
Goals: The aim of this study was to determine the antibiotic resistance profile of serotypes of Streptococcus pneumoniae strains circulating in Bangui. Methodology: A prospective and analytical analysis was carried ou...Goals: The aim of this study was to determine the antibiotic resistance profile of serotypes of Streptococcus pneumoniae strains circulating in Bangui. Methodology: A prospective and analytical analysis was carried out at the National Laboratory of Clinical Biology and Public Health from 2017 to 2022. The strains came from our study on the contribution to the study of antibiotic sensitivity of Streptococcus pneumoniae strains. The multiplex PCR test was used for its cost-effectiveness in terms of amplifiers which can be purified in order to be sequenced. It also makes it possible to detect several germs as well as their serotypes. For a PCR reaction, several elements are involved in the reaction medium or Master Mix. These are the desoxyribonucleotides (dNTPs), the magnesium ions (MgCl2) and the primers. A set of 14 primers divided into 3 classes were used. Class 1 primers served as an internal control by targeting the cpsA gene. It is a highly conserved gene found in capsular loci characterized to date. The primers of the second class were used to target specific serotypes by specific reactions (out of six possibilities). The group reaction was carried out using the primers of the third class in order to carry out an initial screening of the samples and to classify the pneumococcal isolates. Related serotypes were grouped based on the amplification of common genes. Using the technique of electrophoresis on agarose gel and an ultraviolet radiation device, the migration bands are then visualized and analyzed. The data collected had been entered into Excel 2010 and analyzed with Epi info 7. The exact Fischer chi2 test at the 5% threshold, the relative risk and its 95% confidence interval were used to compare the proportions and determine the associations. Results: 187 antibiotic-resistant strains of Streptococcus pneumoniae were collected. The average frequency of serotypes 1, 9A, 4 and untypeable identified were 43.59%, 18.18%, 18.27% and 39.57% respectively. The frequency of serotype 1 was predominant for the age group over five years old with 56.88%. The male sex was predominant with 55.08% for serotype 1. Resistance to penicillin and gentamicin for serotype 1 during this study, for the age group under 5 years old, was 77%. For serotypes 19A and 4, tetracycline resistance was predominant with 20% for the age group under 5 years. The resistance to penicillin and gentamicin of non-typeable serotypes was 33% for the age group under 5 years old. For the age group over 5 years old, resistance to erythromycin predominated at 37%. The distribution of serotypes by sex depending on antibiotic resistance was variable. There was a statistically significant association between identified serotypes and antibiotic resistance (p Conclusion: The study determined serotypes 1, serotypes 19A, serotypes 4 and non-typeable serotypes. These results would be due to the quality of vaccination or poor protection of vaccines.展开更多
【背景】酪蛋白水解蛋白酶L(caseinolytic protease L,ClpL)是热休克蛋白100(heat shock protein 100,HSP100)家族成员,参与多种细胞内生物学过程包括应激耐受反应、长期存活、毒力和抗生素抗性等,在病原菌的致病过程中发挥重要作用。...【背景】酪蛋白水解蛋白酶L(caseinolytic protease L,ClpL)是热休克蛋白100(heat shock protein 100,HSP100)家族成员,参与多种细胞内生物学过程包括应激耐受反应、长期存活、毒力和抗生素抗性等,在病原菌的致病过程中发挥重要作用。【目的】阐明HSP100/ClpL对猪链球菌2型(Streptococcus suis type 2)强毒株的应激耐受和毒力的影响。【方法】利用温敏自杀质粒pSET4s构建了SsClpL基因缺失株ΔclpL;利用大肠杆菌-猪链球菌穿梭质粒pSET2构建了互补株CΔclpL;比较亲本株SS2-1、ΔclpL和CΔclpL在各种应激环境(高温、氧化性应激和酸应激)和血液中的生存能力;利用小鼠感染模型和体内竞争试验评价clpL缺失前后细菌的毒力变化。【结果】clpL缺失后,SS2在各种应激环境中的生存能力明显减弱;同时在猪全血中的存活能力也显著降低;对BALB/c小鼠的致病力有所降低,在体内的定殖能力明显降低。【结论】SsClpL与猪链球菌的应激耐受和致病性密切相关。展开更多
文摘Group B Streptococcus(GBS;Streptococcus agalactiae)is a gram-positive coccus that colonizes the gastrointestinal and genital tracts in adults,as well as the upper respiratory tract in infants.While it has been thought that GBS only results in invasive disease in pregnant females and neonates,recent literature has suggested an increasing incidence of invasive GBS among non-pregnant individuals within the United States.
文摘BACKGROUND Pericarditis is the inflammation of the pericardial sac due to a variety of stimuli that ultimately trigger a stereotyped immune response.This condition accounts for up to 5%of emergency department visits for nonischemic chest pain in Western Europe and North America.The most common symptoms of clinical presentation are chest pain and shortness of breath with associated unique electrocardiographic changes.Acute pericarditis is generally self-limited.However,some cases may be complicated by either tamponade or a large pericardial effusion,which carries a significant risk of recurrence.Risk factors for acute pericarditis include viral infections,cardiac surgery,and autoimmune disorders.A rarer cause of pericardial inflammation includes pneumonia,which can induce purulent pericarditis that has been increasingly rare since the advent of antibiotics.Purulent pericarditis carries a high fatality rate,especially in the setting of tamponade,and is invariably deadly without the administration of antibiotics.Bedside transthoracic echocardiogram is a quick and helpful method that can aid in the diagnosis and management.CASE SUMMARY We present the case of a 62-year-old woman who sought medical attention at the emergency department(ED)due to a 5-day history of chest pain,shortness of breath,and subjective fevers.Laboratory findings in the ED were significant for leukocytosis and elevated erythrocyte sedimentation rate and C-reactive protein.A chest X-ray revealed a new focal density within the left lower lung base,and a bedside point-of-care ultrasound showed a pericardial fluid collection.The patient was subsequently admitted,where she underwent pericardiocentesis.Fluid cultures from drainage grew streptococcus pneumoniae.She was started on broadspectrum antibiotics immediately after the procedure.The patient was ultimately discharged in stable condition with cardiology and infectious disease follow-up.CONCLUSION This case report emphasizes a unique complication of community-acquired pneumonia.Purulent pericarditis due to streptococcus pneumonia occurs via intrathoracic spread of the organism to the pericardium.This condition is virtually fatal without the administration of antibiotics.Therefore,in the context of suspected pneumonia and a new pericardial fluid collection on imaging,clinicians should suspect purulent pericarditis until proven otherwise,which requires emergent intervention.
文摘In the realm of medical rarity,the convergence of infective endocarditis with the development of an aortic root abscess stands as a formidable challenge,often bearing a grim prognosis.Recognizing this perilous condition requires a vigilant eye.Embolic events stemming from infective endocarditis can precipitate acute coronary syndrome,adding another layer of complexity to diagnosis and treatment.
基金supported by the National Key Research and Development Program of China(2022YFD1800904)the National Natural Science Foundation of China(31972650 and 32102673)+1 种基金the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(KYCX22_0780)the China Postdoctoral Science Foundation(2020M682297)。
文摘Toxin–antitoxin(TA)systems,which are prevalent in bacteria and archaea,play diverse roles in bacterial physiology and have been proposed to be significant in stress adaptation.Despite the extensive characterization of numerous TA systems in various bacteria,the investigation of these systems within Streptococcus suis is still limited.Here,we systematically analyzed the type Ⅱ TA systems of 95 S.suis genomes available in the GenBank database using TAfinder.A total of 612 putative type Ⅱ TA systems were retrieved and classified into 10 categories by phylogenetic analysis.Notably,an elevated occurrence of these TA systems was observed among the important prevalent serotypes 2,4,5,9,14,Chz,NCL1,and NCL3 strains.The following study identified the activities of TA systems using 2 strategies and confirmed the regulatory effect of HigBA on the type Ⅶ secretion system in S.suis by measuringβ-galactosidase activity and transcriptional changes.Moreover,we unveiled a hitherto uncharacterized,highly prevalent novel TA system,with the composition of antitoxin–toxin–antitoxin(SS-ATA),which regulates the downstream two-component signaling system.Altogether,this study systematically analyzed the type Ⅱ TA systems within S.suis,highlighting the widespread distribution of Hig BA and SS-ATA as important regulatory elements in S.suis.
文摘BACKGROUND The Streptococcus salivarius(S.salivarius)group,which produces the enzyme urease has been identified as a potential contributor to ammonia production in the gut.Researchers have reported that patients with minimal HE had an increased abundance of the S.salivarius group,which is a specific change in the gut microbiota that distinguishes them from healthy individuals.The correlation between the aggregation of specific bacterial species and fibrosis progression in chronic liver disease(CLD)is yet to be fully elucidated.AIM To quantify S.salivarius using digital PCR(dPCR)as a liver fibrosis marker of CLD.METHODS This study retrospectively analysed 52 patients with CLD.To quantify S.salivarius in patients with CLD using dPCR,we evaluated the specificity and sensitivity of S.salivarius bacterial load using dPCR for a type strain.Next,we evaluated the clinical usefulness of dPCR for S.salivarius load quantification for detecting liver fibrosis in patients with CLD.The liver fibrosis stage was categorized into mild and advanced fibrosis based on pathological findings.RESULTS The dPCR assay revealed that S.salivarius was highly positive for the tnpA gene.The lower limit of quantification for dPCR using the tnpA gene with a 1μL template comprising 1.28×102 CFU/mL was 4.3 copies.After considering the detection range in dPCR,we adjusted the extracted DNA concentration to 5.0×10-4 ng/μL from 200 mg stool samples.The median bacterial loads of S.salivarius in stool sample from patients with mild and advanced fibrosis were 1.9 and 7.4 copies/μL,respectively.The quantification of S.salivarius load was observed more frequently in patients with advanced fibrosis than in those with mild fibrosis(P=0.032).CONCLUSION Quantifying of S.salivarius load using digital PCR is a useful biomarker for liver fibrosis in patients with CLD.
文摘Streptococcus (S.) pyogenes is usually associated with mild infections of the pharynx and skin.However,in some cases,this microorganism can cause potentially lethal invasive infections,such as bacteremic pneumonia,skin and soft-tissue infections,sepsis,meningitis,necrotizing fasciitis,and streptococcal toxic shock syndrome.^([1,2])Although S.pyogenes is currently considered a rare cause of pneumonia,with most cases occurring in patients following influenza,the mortality rate for invasive infections is high.^([3,4])We present a case of S.pyogenes bacteremic pneumonia in a woman with no severe comorbidities,which led to a fatal outcome 9h after admission to the hospital on the third day of the disease onset.
基金supported by the National Natural Science Foundation of China(31871829,31820103010,and 32021005)the Collaborative Innovation Centre of Food Safety and Quality Control in Jiangsu Province(Jiangsu,China).
文摘Streptococcus thermophilus is one of the most prevalent species in stool samples of westernized populations due to continuous exposure to fermented dairy products.However,few studies have explored the effect on host physiology by multiple S.thermophilus strains and considered the inter-strain differences in regulating host.In the present study,we investigated how four S.thermophilus strains influenced the gut microbiota,mucin changes,and host metabolism after 28 days of intervention in conventional mice.The results indicated that the consumption of S.thermophilus affected the host with strain specificity.Among four S.thermophilus strains,DYNDL13-4 and DQHXNQ38M61,especially DQHXNQ38M61,had more effect on host physiology by modulating gut microbiota and host metabolism than LMD9 and 4M6.Ingestion of strains DYNDL13-4 and DQHXNQ38M61 resulted in more remarkable changes in amino acid metabolism and lipid metabolism than that of strains LMD9 and 4M6,which may be related to the elevation of intestinal Bifidobacterium by DYNDL13-4 and DQHXNQ38M61.The enriched Coriobacteriaceae UCG-002,Rikenellaceae RC9 gut group,and Lactobacillus only in the DQHXNQ38M61 group,had a close relationship with the prominent effect of DQHXNQ38M61 on regulating amino acid and lipid metabolism.In addition,DQHXNQ38M61 had a strong influence on degrading colonic mucin fucose by decreasedα-fucosidase activity in feces,and improving mucin sulfation by upregulated Gal3ST2 expression.Comparative genomic analysis revealed that the four S.thermophilus strains belonged to different branches in the phylogenetic tree,and DYNDL13-4 and DQHXNQ38M61 had more genes involved in carbohydrate metabolism,amino acid metabolism,membrane transport,and signal transduction,which may confer the capacity of nutrient utilization and gastrointestinal adaptation of the strains and be associated with their strong regulation in host.Our study provides valuable information for understanding the regulation of host metabolism after consuming different S.thermophilus strains and could facilitate potential personalized applications of S.thermophilus based on strain varieties.
文摘The microbiota is strongly association with cancer.Studies have shown significant differences in the gastric microbiota between patients with gastric cancer(GC)patients and noncancer patients,suggesting that the microbiota may play a role in the development of GC.Although Helicobacter pylori(H.pylori)infection is widely recognized as a primary risk factor for GC,recent studies based on microbiota sequencing technology have revealed that non-H.pylori microbes also have a significant impact on GC.A recent study discovered that Streptococcus anginosus(S.anginosus)is more prevalent in the gastric mucosa of patients with GC than in that of those without GC.S.anginosus infection can spontaneously induce chronic gastritis,mural cell atrophy,mucoid chemotaxis,and heterotrophic hyperplasia,which promote the development of precancerous lesions of GC(PLGC).S.anginosus also disrupts the gastric barrier function,promotes the proliferation of GC cells,and inhibits apoptosis.However,S.anginosus is underrepresented in the literature.Recent reports suggest that it may cause precancerous lesions,indicating its emerging pathogenicity.Modern novel molecular diagnostic techniques,such as polymerase chain reaction,genetic testing,and Ultrasensitive Chromosomal Aneuploidy Detection,can be used to gastric precancerous lesions via microbial markers.Therefore,we present a concise summary of the relationship between S.anginosus and PLGC.Our aim was to further investigate new methods of preventing and treating PLGC by exploring the pathogenicity of S.anginosus on PLGC.
基金supported by the National Natural Science Foundation of China(U22A20520)the Innovation Team Project of Modern Agricultural Industrial Technology System of Guangdong Province,China(2023KJ119)the Natural Science Foundation Program of Guangdong Province,China(2023A1515012206)。
文摘Streptococcus suis serotype 2(S.suis 2)is a zoonotic pathogen that clinically causes severe swine and human infections(such as meningitis,endocarditis,and septicemia).In order to cause widespread diseases in different organs,S.suis 2 must colonize the host,break the blood barrier,and cause exaggerated inflammation.In the last few years,most studies have focused on a single virulence factor and its influences on the host.Membrane vesicles(MVs)can be actively secreted into the extracellular environment contributing to bacteria-host interactions.Gram-negative bacteria-derived outer membrane vesicles(OMVs)were recently shown to activate host Caspase-11-mediated non-canonical inflammasome pathway via deliverance of OMV-bound lipopolysaccharide(LPS),causing host cell pyroptosis.However,little is known about the effect of the MVs from S.suis 2(Gram-positive bacteria without LPS)on cell pyroptosis.Thus,we investigated the molecular mechanism by which S.suis 2 MVs participate in endothelial cell pyroptosis.In this study,we used proteomics,electron scanning microscopy,fluorescence microscope,Western blotting,and bioassays,to investigate the MVs secreted by S.suis 2.First,we demonstrated that S.suis 2 secreted MVs with an average diameter of 72.04 nm,and 200 proteins in MVs were identified.Then,we showed that MVs were transported to cells via mainly dynamin-dependent endocytosis.The S.suis 2 MVs activated NLRP3/Caspase-1/GSDMD canonical inflammasome signaling pathway,resulting in cell pyroptosis,but it did not activate the Caspase-4/-5 pathway.More importantly,endothelial cells produce large amounts of reactive oxygen species(ROS)and lost their mitochondrial membrane potential under induction by S.suis 2 MVs.The results in this study suggest for the first time that MVs from S.suis 2 were internalized by endothelial cells via mainly dynamin-dependent endocytosis and might promote NLRP3/Caspase-1/GSDMD pathway by mitochondrial damage,which produced mtDNA and ROS under induction,leading to the pyroptosis of endothelial cells.
基金the Research Grants from Universiti Putra Malaysia(UPM/800-3/3/1/GPB/2020/9683800)Ministry of Higher Education under the Fundamental Research Grant Scheme(FRGS/1/2023/WAB04/UPM/01/4).
文摘Objective:To address the lack of research on invasive group B Streptococcus(GBS)infections in Malaysia and Southeast Asia through a comprehensive analysis of GBS isolates obtained from hospitals.Methods:Medical records from patients with GBS infection isolated from the sterile site,such as blood and cerebrospinal fluid from 14 July 2019 to 15 December 2020,were reviewed from six major hospitals in Peninsular Malaysia.Inclusion criteria were invasive GBS,sterile sites and non-repeated GBS isolated from the same patients in the same admission.Viable isolates were re-identified for GBS and serotyped.Results:A total of 118 patients were eligible,with a majority of non-pregnant adults(76.3%).Over half of the patients(62.7%)had underlying medical conditions,with diabetes as the most common disease,followed by respiratory disease,renal disease,cardiovascular disease and skin and soft tissue disease.The most common manifestations were sepsis,followed by soft tissue abscess,diabetic foot ulcer,wet gangrene and cellulitis.The overall mortality was 7.6%.The most common serotype was serotype桋.Conclusions:Invasive GBS infection among non-pregnant adults showed a rising trend,particularly among diabetic individuals.The study underscores the importance of reducing risk factors and highlights the necessity of developing GBS vaccination as a preventive strategy for both infants and adults.
基金supported by the National Natural Science Foundation of China(82072148)Zhejiang Provincial Basic Public Welfare Research Program of Zhejiang Province(LGF21H150002)+1 种基金Zhejiang Medicine and Health Science and Technology Project(2022RC245&2023KY255)Ningbo Municipal Natural Science Foundation(2023J134).
文摘BACKGROUND:Streptococcus pneumoniae(S.pneumoniae)is a common pathogen that causes bacterial pneumonia.However,with increasing bacterial resistance,there is an urgent need to develop new drugs to treat S.pneumoniae infections.Nanodefensin with a 14-carbon saturated fatty acid(ND-C14)is a novel nanoantimicrobial peptide designed by modifying myristic acid at the C-terminus of humanα-defensin 5(HD5)via an amide bond.However,it is unclear whether ND-C14 is effective against lung infections caused by S.pneumoniae.METHODS:In vitro,three groups were established,including the control group,and the HD5 and ND-C14 treatment groups.A virtual colony-count assay was used to evaluate the antibacterial activity of HD5 and ND-C14 against S.pneumoniae.The morphological changes of S.pneumoniae treated with HD5 or ND-C14 were observed by scanning electron microscopy.In vivo,mice were divided into sham,vehicle,and ND-C14 treatment groups.Mice in the sham group were treated with 25μL of phosphate-buffered saline(PBS).Mice in the vehicle and ND-C14 treatment groups were treated with intratracheal instillation of 25μL of bacterial suspension with 2×108 CFU/mL(total bacterial count:5×10^(6) CFU),and then the mice were given 25μL PBS or intratracheally injected with 25μL of ND-C14(including 20μg or 50μg),respectively.Survival rates were evaluated in the vehicle and ND-C14 treatment groups.Bacterial burden in the blood and bronchoalveolar lavage fluid were counted.The lung histology of the mice was assessed.A propidium iodide uptake assay was used to clarify the destructive eff ect of ND-C14 against S.pneumoniae.RESULTS:Compared with HD5,ND-C14 had a better bactericidal eff ect against S.pneumoniae because of its stronger ability to destroy the membrane structure of S.pneumoniae in vitro.In vivo,ND-C14 significantly delayed the death time and improved the survival rate of mice infected with S.pneumoniae.ND-C14 reduced bacterial burden and lung tissue injury.Moreover,ND-C14 had a membrane permeation eff ect on S.pneumoniae,and its destructive ability increased with increasing ND-C14 concentration.CONCLUSION:The ND-C14 may improve bactericidal eff ects on S.pneumoniae both in vitro and in vivo.
基金Supported by the Scientific Research Project from the Health Commission of Mianyang City,No.201903.
文摘BACKGROUND Streptococcus gallolyticus subspecies pasteurianus(SGSP)is a rare pathogen responsible for infant sepsis and meningitis and is potentially overlooked because it is not included in routine group B streptococcal screenings.Hence,we present a case of SGSP-induced infant meningitis and sepsis,accompanied by bronchopneumonia induced by multidrug-resistant Staphylococcus aureus(MRSA),providing insights into the identification,management,and prognosis of this bacterial infection.CASE SUMMARY A 45-day-old female infant presented with two episodes of high fever(maximum temperature:39.5°C)and two generalized grand mal seizure episodes that lasted over ten seconds and self-resolved without concomitant symptoms.Postadmission,the patient’s C-reactive protein level was 40.73 mg/L,white blood cell count was 13.42×10^(9)/L,neutrophil ratio was 78.4%,procalcitonin level was 7.89μg/L,cerebrospinal fluid(CSF)white cell count was 36×10^(6)/L,multinucleated cell ratio was 95.2%,and protein concentration was 0.41 g/L.Blood and CSF culture revealed that the pathogen was SGSP.The bacterium was sensitive to ampicillin,furazolidone,penicillin,lincomycin,moxifloxacin,rifampicin,vancomycin,and levofloxacin but resistant to clindamycin and tetracycline.Sputum culture revealed the presence of MRSA,which was sensitive to vancomycin.The patient was diagnosed with meningitis and sepsis caused by SGSP,accompanied by bronchopneumonia induced by MRSA.Ceftriaxone(100 mg/kg/d)combined with vancomycin(10 mg/kg/dose,q6h)was given as an anti-infective treatment postadmission.After 12 days of treatment,the infant was discharged from the hospital with normal CSF,blood culture,and routine blood test results,and no complications,such as subdural effusion,were observed on cranial computed tomography.No growth retardation or neurological sequelae occurred during follow-up.CONCLUSION SGPSP-induced infant bacterial meningitis and sepsis should be treated with prompt blood and CSF cultures,and a sensitive antibiotic therapy to ensure a favorable prognosis.
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.
文摘Rationale:Acute otitis media is a common disease in early childhood,and is usually caused by Streptococcus pneumoniae(S.pneumoniae).Acute mastoiditis is a complication of acute otitis media and can involve not only the mucoperiosteum of the middle ear but can also spread to the periosteum by destroying the mastoid bone(acute coalescent mastoiditis).In addition,the infection can extend through the surrounding bones or the emissary veins beyond the mastoid’s air cells,leading to subperiosteal abscesses.Patient’s Concern:A 16-month-old female patient was hospitalized due to the purulent discharge of the left ear and the symptoms of right mastoiditis(swelling and redness of the skin).Diagnosis:Bilateral acute coalescent mastoiditis caused by S.pneumoniae infection.The computer tomography revealed bilateral bone destruction of the mastoid and abscesses found behind the auricle on both sides.Interventions:The patient underwent intravenous antibiotic therapy and surgical treatment.Outcomes:The patient was discharged 14 days after hospitalization with an improved condition.Lessons:Improperly treated acute coalescent mastoiditis can lead to extracranial and intracranial complications,sometimes serious and even life-threatening.Complications are prevalent in children under 2 years,in whom the disease progresses more rapidly and severely.The vaccination with a 13-valent vaccine may not result in sufficient immunity against S.pneumoniae,a predominant pathogen in children affected by acute coalescent mastoiditis.
基金Supported by Corps Guiding Plan Project of Xinjiang Uygur Autonomous Region,China,No.2022ZD031Financial Science and Technology Plan Project of Shihezi,Xinjiang Uygur Autonomous Region of China,No.2022NY01Research Project of Shihezi University of Shihezi,Xinjiang Uygur Autonomous Region of China,No.ZZZC202072A.
文摘BACKGROUND Lung abscess found on chest X-ray and computed tomography examinations is rare in infants and young children.Several pathogens can cause lung abscesses,with the most common pathogens being anaerobes,Streptococci and Staphylococcus aureus.Streptococcus pseudopneumoniae(S.pseudopneumoniae)is a member of the Streptococcaceae family,and is mainly isolated from respiratory tract specimens.There are currently no cases of lung abscess caused by S.pseudopneumoniae in the literature.CASE SUMMARY A 2-year-old boy was admitted to hospital due to persistent cough and fever.Lung computed tomography examination suggested the formation of a lung abscess.His diagnosis was not confirmed by testing for serum respiratory pathogens(6 items),respiratory pathogen nucleic acid(27 items),and laboratory culture.Finally,metagenomic next-generation sequencing of bronchoalveolar lavage fluid revealed the presence of S.pseudopneumoniae,confirming its role in causing the lung abscess.After receiving antibiotic treatment,reexamination with lung computed tomography showed that the abscess was resorbed and the patient’s outcome was good.CONCLUSION This is the first report of a lung abscess in a child caused by S.pseudopneumoniae infection.Metagenomic next-generation sequencing of bronchoalveolar lavage fluid is helpful in achieving rapid and accurate pathogen identification.
文摘BACKGROUND The oral cavity harbors more than 700 species of bacteria,which play crucial roles in the development of various oral diseases including caries,endodontic infection,periodontal infection,and diverse oral diseases.AIM To investigate the antimicrobial action of Cymbopogon Schoenanthus and Pelargonium graveolens essential oils against Streptococcus mutans,Staphylococcus aureus,Candida albicans,Ca.dubliniensis,and Ca.krusei.METHODS Minimum microbicidal concentration was determined following Clinical and Laboratory Standards Institute documents.The synergistic antimicrobial activity was evaluated using the Broth microdilution checkerboard method,and the antibiofilm activity was evaluated with the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay.Data were analyzed by one-way analysis of variance followed by the Tukey post-hoc test(P≤0.05).RESULTS C.schoenanthus and P.graveolens essential oils were as effective as 0.12%chlorhexidine against S.mutans and St.aureus monotypic biofilms after 24 h.After 24 h P.graveolens essential oil at 0.25%was more effective than the nystatin group,and C.schoenanthus essential oil at 0.25%was as effective as the nystatin group.CONCLUSION C.schoenanthus and P.graveolens essential oils are effective against S.mutans,St.aureus,Ca.albicans,Ca.dubliniensis,and Ca.krusei at different concentrations after 5 min and 24 h.
文摘Goals: The aim of this study was to determine the antibiotic resistance profile of serotypes of Streptococcus pneumoniae strains circulating in Bangui. Methodology: A prospective and analytical analysis was carried out at the National Laboratory of Clinical Biology and Public Health from 2017 to 2022. The strains came from our study on the contribution to the study of antibiotic sensitivity of Streptococcus pneumoniae strains. The multiplex PCR test was used for its cost-effectiveness in terms of amplifiers which can be purified in order to be sequenced. It also makes it possible to detect several germs as well as their serotypes. For a PCR reaction, several elements are involved in the reaction medium or Master Mix. These are the desoxyribonucleotides (dNTPs), the magnesium ions (MgCl2) and the primers. A set of 14 primers divided into 3 classes were used. Class 1 primers served as an internal control by targeting the cpsA gene. It is a highly conserved gene found in capsular loci characterized to date. The primers of the second class were used to target specific serotypes by specific reactions (out of six possibilities). The group reaction was carried out using the primers of the third class in order to carry out an initial screening of the samples and to classify the pneumococcal isolates. Related serotypes were grouped based on the amplification of common genes. Using the technique of electrophoresis on agarose gel and an ultraviolet radiation device, the migration bands are then visualized and analyzed. The data collected had been entered into Excel 2010 and analyzed with Epi info 7. The exact Fischer chi2 test at the 5% threshold, the relative risk and its 95% confidence interval were used to compare the proportions and determine the associations. Results: 187 antibiotic-resistant strains of Streptococcus pneumoniae were collected. The average frequency of serotypes 1, 9A, 4 and untypeable identified were 43.59%, 18.18%, 18.27% and 39.57% respectively. The frequency of serotype 1 was predominant for the age group over five years old with 56.88%. The male sex was predominant with 55.08% for serotype 1. Resistance to penicillin and gentamicin for serotype 1 during this study, for the age group under 5 years old, was 77%. For serotypes 19A and 4, tetracycline resistance was predominant with 20% for the age group under 5 years. The resistance to penicillin and gentamicin of non-typeable serotypes was 33% for the age group under 5 years old. For the age group over 5 years old, resistance to erythromycin predominated at 37%. The distribution of serotypes by sex depending on antibiotic resistance was variable. There was a statistically significant association between identified serotypes and antibiotic resistance (p Conclusion: The study determined serotypes 1, serotypes 19A, serotypes 4 and non-typeable serotypes. These results would be due to the quality of vaccination or poor protection of vaccines.
文摘【背景】酪蛋白水解蛋白酶L(caseinolytic protease L,ClpL)是热休克蛋白100(heat shock protein 100,HSP100)家族成员,参与多种细胞内生物学过程包括应激耐受反应、长期存活、毒力和抗生素抗性等,在病原菌的致病过程中发挥重要作用。【目的】阐明HSP100/ClpL对猪链球菌2型(Streptococcus suis type 2)强毒株的应激耐受和毒力的影响。【方法】利用温敏自杀质粒pSET4s构建了SsClpL基因缺失株ΔclpL;利用大肠杆菌-猪链球菌穿梭质粒pSET2构建了互补株CΔclpL;比较亲本株SS2-1、ΔclpL和CΔclpL在各种应激环境(高温、氧化性应激和酸应激)和血液中的生存能力;利用小鼠感染模型和体内竞争试验评价clpL缺失前后细菌的毒力变化。【结果】clpL缺失后,SS2在各种应激环境中的生存能力明显减弱;同时在猪全血中的存活能力也显著降低;对BALB/c小鼠的致病力有所降低,在体内的定殖能力明显降低。【结论】SsClpL与猪链球菌的应激耐受和致病性密切相关。
