All Stories

  1. Combinatorial action of regulatory systems generates colistin heteroresistance
  2. A multivalent subunit vaccine augments pre-existing immunity to protect against T3SS-positive Pseudomonas aeruginosa but reveals immunological interference against ExlA-positive strains
  3. Phosphoethanolamine-modified lipid A enables antimicrobial resistance and atypical signaling properties in the marine pathogen P. damselae subsp. damselae
  4. Acquired mutations in transcriptional regulator hns and lipopolysaccharide biosynthesis and modification genes impact colistin resistance and fitness of mcr -...
  5. Genomic, proteolytic, and phenotypic characterization of Pseudomonas aeruginosa isolates causing infective endocarditis
  6. Ethnicity-specific microbiome in early childhood caries: a functional perspective of oral biofilm
  7. Characterization of Borrelia-Derived Extracellular Vesicles: Implications for Pathogenesis and Diagnostics
  8. Helicobacter pylori allelic variation in cell surface genes influences human exoproteome binding and stomach tissue adherence
  9. MetaTracer: A nucleotide alignment-based framework for high-resolution taxonomic and transcript assignment in metatranscriptomic data
  10. Draft genomes of three cultured members of a psychrophilic Francisella species cultivated from the Chesapeake Bay in winter
  11. Sex-dependent changes in insular cortex connectivity in a rat model of comorbid pain
  12. L-PaF/E/ME/BECC438b Primes Interferon-Mediated Immune-Stromal Lung Networks against Pseudomonas Aeruginosa in Mice
  13. Integrated immunological and metabolic analysis reveals dose-dependent divergence in protective responses to a Pseudomonas aeruginosa vaccine
  14. Multi-omic comparative analysis of members of the Akkermansia genus reveals species-specific adaptations to growth in mucin.
  15. Polyphosphazene-Mediated Assembly of TLR4 and TLR7/8 Agonists Enables a Potent Nano-Adjuvant Delivery System for Hepatitis C Virus Vaccine Antigens
  16. Exploring the complex interplay of polymyxin resistance mechanisms, lipid A variations, and virulence factors in Escherichia coli and Klebsiella pneumoniae
  17. Polyphosphazene-Mediated Assembly of TLR4 and TLR7/8 Agonists Enables a Potent Nano-Adjuvant Delivery System for Hepatitis C Virus Vaccine Antigens
  18. A critical role for Vibrio parahaemolyticus LPS to mediate evasion of host immune response during infection
  19. Combinatorial action of regulatory systems generates colistin heteroresistance
  20. Mutational signature analysis predicts bacterial hypermutation and multidrug resistance
  21. Draft genome sequences of evolutionary distant Yersinia species representatives
  22. Magnesium depletion unleashes two unusual modes of colistin resistance with different fitness costs
  23. A lipidomics-based method to eliminate negative urine culture in general population
  24. A pH-sensitive motif in an outer membrane protein activates bacterial membrane vesicle production
  25. Mutational signature analysis predicts bacterial hypermutation and multidrug resistance
  26. BECC-engineered live-attenuated Shigella vaccine candidates display reduced endotoxicity with robust immunogenicity in mice
  27. Vaccination with a Protective Ipa Protein-Containing Nanoemulsion Differentially Alters the Transcriptomic Profiles of Young and Elderly Mice following Shigella Infection
  28. Lipid A modification of colistin-resistant Klebsiella pneumoniae does not alter innate immune response in a mouse model of pneumonia
  29. A Lipidomics-Based Method to Eliminate Negative Urine Culture in General Population
  30. The lipid-mediated mechanism of mechanosensitive channel MscS inactivation
  31. Structural determination of Rickettsia lipid A without chemical extraction confirms shorter acyl chains in later-evolving spotted fever group pathogens
  32. Divergent Pseudomonas aeruginosa LpxO enzymes perform site-specific lipid A 2-hydroxylation
  33. Comparison of three rapid diagnostic tests for bloodstream infections using Benefit-risk Evaluation Framework (BED-FRAME)
  34. Characterization of spatial lipidomic signatures in tick-bitten guinea pig skin as a model for host-vector-pathogen interaction profiling
  35. Mouse Lung Inflation Protocol for Mass Spectrometry Imaging (DMS22) v1
  36. Physicochemical characterization of biological and synthetic forms of two lipid A-based TLR4 agonists
  37. Genomic and Functional Characterization of Longitudinal Pseudomonas aeruginosa Isolates from Young Patients with Cystic Fibrosis
  38. Interpretable dimensionality reduction and classification of mass spectrometry imaging data in a visceral pain model via non-negative matrix factorization
  39. A protein subunit vaccine elicits a balanced immune response that protects against Pseudomonas pulmonary infection
  40. Benchmarking tools for detecting longitudinal differential expression in proteomics data allows establishing a robust reproducibility optimization regression approach
  41. A Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Direct-from-Urine-Specimen Diagnostic for Gram-Negative Pathogens
  42. Enhancing the Protection of Influenza Virus Vaccines with BECC TLR4 Adjuvant in Aged Mice
  43. Lipid A Variants Activate Human TLR4 and the Noncanonical Inflammasome Differently and Require the Core Oligosaccharide for Inflammasome Activation
  44. Position-Specific Secondary Acylation Determines Detection of Lipid A by Murine TLR4 and Caspase-11
  45. MgrB-Dependent Colistin Resistance in Klebsiella pneumoniae Is Associated with an Increase in Host-to-Host Transmission
  46. Remodeling of Lipid A in Pseudomonas syringae pv. phaseolicola In Vitro
  47. A Novel Lipid-Based MALDI-TOF Assay for the Rapid Detection of Colistin-Resistant Enterobacter Species
  48. Position-specific secondary acylation determines detection of lipid A by murine TLR4 and caspase-11
  49. Rapid identification of mcr-1-positive Escherichia coli from patient urine using a novel lipid-based MALDI-TOF-MS assay
  50. Human TLR4 and noncanonical inflammasome differ in their ability to respond to distinct lipid A variants
  51. MgrB dependent colistin resistance in Klebsiella pneumoniae is associated with an increase in host-to-host transmission
  52. Species-Specific Endotoxin Stimulus Determines Toll-Like Receptor 4- and Caspase 11-Mediated Pathway Activation Characteristics
  53. Loss of RND-type multidrug efflux pumps triggers iron starvation and lipid A modifications in Pseudomonas aeruginosa
  54. Bacterial factors drive the differential targeting of Guanylate Binding Proteins to Francisella and Shigella
  55. Lipid A Structural Divergence in Rickettsia Pathogens
  56. Inactivation of AdeABC and AdeIJK efflux pumps elicits specific nonoverlapping transcriptional and phenotypic responses in Acinetobacter baumannii
  57. Early evolutionary loss of the lipid A modifying enzyme PagP resulting in innate immune evasion in Yersinia pestis
  58. Scnn1b-Transgenic BALB/c Mice as a Model of Pseudomonas aeruginosa Infections of the Cystic Fibrosis Lung
  59. Synergistic Biophysical Techniques Reveal Structural Mechanisms of Engineered Cationic Antimicrobial Peptides in Lipid Model Membranes
  60. Toll-like Receptor 4-Independent Effects of Lipopolysaccharide Identified Using Longitudinal Serum Proteomics
  61. Maintenance of Deep Lung Architecture and Automated Airway Segmentation for 3D Mass Spectrometry Imaging
  62. The UDP‐GalNAcA biosynthesis genes gna ‐ gne2 are required to maintain cell envelope integrity and in vivo fitness in multi‐drug resistant Acinetobacter baumannii
  63. Lipopolysaccharides from Different Burkholderia Species with Different Lipid A Structures Induce Toll-Like Receptor 4 Activation and React with Melioidosis Patient Sera
  64. Repurposing Eukaryotic Kinase Inhibitors as Colistin Adjuvants in Gram-Negative Bacteria
  65. Efflux Pumps of Burkholderia thailandensis Control the Permeability Barrier of the Outer Membrane
  66. Model-Based Spectral Library Approach for Bacterial Identification via Membrane Glycolipids
  67. Tryptamine derivatives disarm colistin resistance in polymyxin-resistant gram-negative bacteria
  68. Small Molecule Potentiation of Gram-Positive Selective Antibiotics against Acinetobacter baumannii
  69. Bacterial medium-chain 3-hydroxy fatty acid metabolites trigger immunity in Arabidopsis plants
  70. Analysis of Pseudomonas aeruginosa biofilm membrane vesicles supports multiple mechanisms of biogenesis
  71. Temporal proteomic profiling reveals changes that support Burkholderia biofilms
  72. Elastic behavior of model membranes with antimicrobial peptides depends on lipid specificity andd-enantiomers
  73. Rapid Microbial Identification and Antibiotic Resistance Detection by Mass Spectrometric Analysis of Membrane Lipids
  74. A Prospective Study of Acinetobacter baumannii Complex Isolates and Colistin Susceptibility Monitoring by Mass Spectrometry of Microbial Membrane Glycolipids
  75. Genomic and Phenotypic Diversity among Ten Laboratory Isolates of Pseudomonas aeruginosa PAO1
  76. Pathogen Identification Direct From Polymicrobial Specimens Using Membrane Glycolipids
  77. Phylogenomics of colistin-susceptible and resistant XDR Acinetobacter baumannii
  78. Mass Spectrometry-based Structural Analysis and Systems Immunoproteomics Strategies for Deciphering the Host Response to Endotoxin
  79. RickettsiaLipid A Biosynthesis Utilizes the Late Acyltransferase LpxJ for Secondary Fatty Acid Addition
  80. In Vivo Intradermal Delivery of Bacteria by Using Microneedle Arrays
  81. A lipid A-based TLR4 mimetic effectively adjuvants a Yersinia pestis rF-V1 subunit vaccine in a murine challenge model
  82. Correction to: Top Down Tandem Mass Spectrometric Analysis of a Chemically Modified Rough-Type Lipopolysaccharide Vaccine Candidate
  83. Optimized surface acoustic wave nebulization facilitates bacterial phenotyping
  84. Comprehensive analysis of clinical Burkholderia pseudomallei isolates demonstrates conservation of unique lipid A structure and TLR4-dependent innate immune activation
  85. Top Down Tandem Mass Spectrometric Analysis of a Chemically Modified Rough-Type Lipopolysaccharide Vaccine Candidate
  86. CXC Chemokines Exhibit Bactericidal Activity against Multidrug-Resistant Gram-Negative Pathogens
  87. Host-based lipid inflammation drives pathogenesis in Francisella infection
  88. Probing the sRNA regulatory landscape of P. aeruginosa : post-transcriptional control of determinants of pathogenicity and antibiotic susceptibility
  89. Lipid A structural modifications in extreme conditions and identification of unique modifying enzymes to define the Toll-like receptor 4 structure-activity relationship
  90. Expression level of human TLR4 rather than sequence is the key determinant of LPS responsiveness
  91. Mass spectrometry analysis of intact Francisella bacteria identifies lipid A structure remodeling in response to acidic pH stress
  92. Small molecule adjuvants that suppress both chromosomal and mcr-1 encoded colistin-resistance and amplify colistin efficacy in polymyxin-susceptible bacteria
  93. Structural basis of MsbA-mediated lipopolysaccharide transport
  94. Structural modification of LPS in colistin-resistant, KPC-producing Klebsiella pneumoniae
  95. Bacterial lipids: powerful modifiers of the innate immune response
  96. Identification of the ESKAPE pathogens by mass spectrometric analysis of microbial membrane glycolipids
  97. Rationally Designed TLR4 Ligands for Vaccine Adjuvant Discovery
  98. Structural Modification of Lipopolysaccharide Conferred by mcr-1 in Gram-Negative ESKAPE Pathogens
  99. Infection-derived lipids elicit an immune deficiency circuit in arthropods
  100. Monophosphoryl Lipid A Enhances Efficacy of a Francisella tularensis LVS-Catanionic Nanoparticle Subunit Vaccine against F. tularensis Schu S4 Challenge by Augmenting both Humoral and Cellular Immunity
  101. In Vivo Fitness Adaptations of Colistin-Resistant Acinetobacter baumannii Isolates to Oxidative Stress
  102. Global Analysis and Comparison of the Transcriptomes and Proteomes of Group A Streptococcus Biofilms
  103. Autopiquer - a Robust and Reliable Peak Detection Algorithm for Mass Spectrometry
  104. 1,2,4-Triazolidine-3-thiones Have Specific Activity against Acinetobacter baumannii among Common Nosocomial Pathogens
  105. Rapid lipid a structure determination via surface acoustic wave nebulization and hierarchical tandem mass spectrometry algorithm
  106. Norharmane matrix enhances detection of endotoxin by MALDI-MS for simultaneous profiling of pathogen, host and vector systems
  107. Structural derivation of lipid A fromCronobacter sakazakiiusing tandem mass spectrometry
  108. A Pseudomonas aeruginosa hepta-acylated lipid A variant associated with cystic fibrosis selectively activates human neutrophils
  109. Type IV pili promote early biofilm formation byClostridium difficile
  110. Second generation modifiers of colistin resistance show enhanced activity and lower inherent toxicity
  111. Potentiation of Francisella resistance to conventional antibiotics through small molecule adjuvants
  112. Modification of the 1-Phosphate Group during Biosynthesis of Capnocytophaga canimorsus Lipid A
  113. Genotypic and phenotypic analyses of a Pseudomonas aeruginosa chronic bronchiectasis isolate reveal differences from cystic fibrosis and laboratory strains
  114. A PmrB-Regulated Deacetylase Required for Lipid A Modification and Polymyxin Resistance in Acinetobacter baumannii
  115. Site-specific activity of the acyltransferases HtrB1 and HtrB2 inPseudomonas aeruginosalipid A biosynthesis
  116. Colistin-Resistant Acinetobacter baumannii: Beyond Carbapenem Resistance
  117. TheprrF-Encoded Small Regulatory RNAs Are Required for Iron Homeostasis and Virulence of Pseudomonas aeruginosa
  118. Bordetella parapertussis PagP Mediates the Addition of Two Palmitates to the Lipopolysaccharide Lipid A
  119. Characterization of BPSS1521 (bprD), a Regulator of Burkholderia pseudomallei Virulence Gene Expression in the Mouse Model
  120. Noncanonical Inflammasome Activation of Caspase-4/Caspase-11 Mediates Epithelial Defenses against Enteric Bacterial Pathogens
  121. Guanylate binding proteins promote caspase-11–dependent pyroptosis in response to cytoplasmic LPS
  122. Identification and Quantitation of Biomarkers for Radiation-induced Injury via Mass Spectrometry
  123. Mass Spectrometry Imaging Enriches Biomarker Discovery Approaches with Candidate Mapping
  124. Novel Catanionic Surfactant Vesicle Vaccines Protect against Francisella tularensis LVS and Confer Significant Partial Protection against F. tularensis Schu S4 Strain
  125. A divergent Pseudomonas aeruginosa palmitoyltransferase essential for cystic fibrosis‐specific lipid A
  126. Survey of Innate Immune Responses to Burkholderia pseudomallei in Human Blood Identifies a Central Role for Lipopolysaccharide
  127. Small Molecule Downregulation of PmrAB Reverses Lipid A Modification and Breaks Colistin Resistance
  128. Enzymatic Modification of Lipid A by ArnT Protects Bordetella bronchiseptica against Cationic Peptides and Is Required for Transmission
  129. Cytoplasmic LPS Activates Caspase-11: Implications in TLR4-Independent Endotoxic Shock
  130. Influence of Lipid A Acylation Pattern on Membrane Permeability and Innate Immune Stimulation
  131. Unique Structural Modifications Are Present in the Lipopolysaccharide from Colistin-Resistant Strains of Acinetobacter baumannii
  132. Increased Long Chain acyl-Coa Synthetase Activity and Fatty Acid Import Is Linked to Membrane Synthesis for Development of Picornavirus Replication Organelles
  133. The TLR4 antagonist Eritoran protects mice from lethal influenza infection
  134. Induction of the Yersinia pestis PhoP-PhoQ Regulatory System in the Flea and Its Role in Producing a Transmissible Infection
  135. Activities of Vancomycin-Containing Regimens against Colistin-Resistant Acinetobacter baumannii Clinical Strains
  136. Turning up Francisella pathogenesis
  137. Characterization of the AggR Regulon in Enteroaggregative Escherichia coli
  138. Humanized TLR4/MD-2 Mice Reveal LPS Recognition Differentially Impacts Susceptibility to Yersinia pestis and Salmonella enterica
  139. Correction for Li et al., LPS remodeling is an evolved survival strategy for bacteria
  140. Surface Acoustic Wave Nebulization Facilitating Lipid Mass Spectrometric Analysis
  141. LPS remodeling is an evolved survival strategy for bacteria
  142. Role of Francisella Lipid A Phosphate Modification in Virulence and Long-Term Protective Immune Responses
  143. A Transposon Site Hybridization Screen Identifies galU and wecBC as Important for Survival of Yersinia pestis in Murine Macrophages
  144. Salmonellaexpressing detoxified lipopolysaccharide is immunogenic and protective both as an attenuated vaccine and for delivery of foreign antigens
  145. A rapid one-step method for the characterization of membrane lipid remodeling in Francisella using matrix-assisted laser desorption ionization time-of-flight tandem mass spectrometry
  146. Evaluation of the Ability of LL-37 to Neutralise LPS In Vitro and Ex Vivo
  147. A rapid one-step method for the characterization of membrane lipid remodeling inFrancisellausing matrix-assisted laser desorption ionization time-of-flight tandem mass spectrometry
  148. Salmonella enterica Serovar Enteritidis Core O Polysaccharide Conjugated to H:g,m Flagellin as a Candidate Vaccine for Protection against Invasive Infection withS.Enteritidis
  149. Role of pagL and lpxO in Bordetella bronchiseptica Lipid A Biosynthesis
  150. Vanadate and triclosan synergistically induce alginate production by Pseudomonas aeruginosa strain PAO1
  151. Automated Lipid A Structure Assignment from Hierarchical Tandem Mass Spectrometry Data
  152. In VitroSusceptibility of Burkholderia vietnamiensis to Aminoglycosides
  153. Mutations of Francisella novicida that Alter the Mechanism of Its Phagocytosis by Murine Macrophages
  154. Comprehensive structure characterization of lipid a extracted from Yersinia pestis for determination of its phosphorylation configuration
  155. Francisella Tularensis Blue–Gray Phase Variation Involves Structural Modifications of Lipopolysaccharide O-Antigen, Core and Lipid A and Affects Intramacrophage Survival and Vaccine Efficacy
  156. The Role of Pseudomonas Lipopolysaccharide in Cystic Fibrosis Airway Infection
  157. Human Toll-like receptor 4 responses toP. gingivalisare regulated by lipid A 1- and 4′-phosphatase activities
  158. A Protein Important for Antimicrobial Peptide Resistance, YdeI/OmdA, Is in the Periplasm and Interacts with OmpD/NmpC
  159. The structurally similar, penta-acylated lipopolysaccharides of Porphyromonas gingivalis and Bacteroides elicit strikingly different innate immune responses
  160. Role of CFTR, Pseudomonas aeruginosa and Toll-like receptors in cystic fibrosis lung inflammation
  161. A Straight Path to Circular Proteins
  162. A sensitive liquid chromatography/mass spectrometry-based assay for quantitation of amino-containing moieties in lipid A
  163. Determination of pyrophosphorylated forms of lipid A in Gram-negative bacteria using a multivaried mass spectrometric approach
  164. Acyl Chain Specificity of the Acyltransferases LpxA and LpxD and Substrate Availability Contribute to Lipid A Fatty Acid Heterogeneity in Porphyromonas gingivalis
  165. Pseudomonas aeruginosa activates caspase 1 through Ipaf
  166. A Francisella Mutant in Lipid A Carbohydrate Modification Elicits Protective Immunity
  167. Activation of Toll-like receptors by Burkholderia pseudomallei
  168. Unique Lipid A Modifications inPseudomonas aeruginosaIsolated from the Airways of Patients with Cystic Fibrosis
  169. Structural heterogeneity and environmentally regulated remodeling of Francisella tularensis subspecies novicida lipid a characterized by tandem mass spectrometry
  170. Identification of an Orphan Response Regulator Required for the Virulence of Francisella spp. and Transcription of Pathogenicity Island Genes
  171. PmrA(Con) Confers pmrHFIJKL-Dependent EGTA and Polymyxin Resistance on msbB Salmonella by Decorating Lipid A with Phosphoethanolamine
  172. Growth phenotypes of Pseudomonas aeruginosa lasR mutants adapted to the airways of cystic fibrosis patients
  173. The Structure and Function of Francisella Lipopolysaccharide
  174. Immunostimulatory Properties of the Emerging Pathogen Stenotrophomonas maltophilia
  175. Comparison of Francisella tularensis genomes reveals evolutionary events associated with the emergence of human pathogenic strains
  176. Differentiation and Distribution of Colistin- and Sodium Dodecyl Sulfate-Tolerant Cells in Pseudomonas aeruginosa Biofilms
  177. Lack of In Vitro and In Vivo Recognition of Francisella tularensis Subspecies Lipopolysaccharide by Toll-Like Receptors
  178. Characterization of Late Acyltransferase Genes of Yersinia pestis and Their Role in Temperature-Dependent Lipid A Variation
  179. The Pseudomonas aeruginosa Lipid A Deacylase: Selection for Expression and Loss within the Cystic Fibrosis Airway
  180. Exopolysaccharides fromBurkholderia cenocepaciaInhibit Neutrophil Chemotaxis and Scavenge Reactive Oxygen Species
  181. Mouse Paneth Cell Secretory Responses to Cell Surface Glycolipids of Virulent and Attenuated Pathogenic Bacteria
  182. Inhibition of Salmonella enterica Serovar Typhimurium Lipopolysaccharide Deacylation by Aminoarabinose Membrane Modification
  183. Purification and characterization of deacylated and/or palmitoylated lipid A species unique to Salmonella enterica serovar Typhimurium
  184. Use of Phage Display To Identify Potential Pseudomonas aeruginosa Gene Products Relevant to Early Cystic Fibrosis Airway Infections
  185. LPS, TLR4 and infectious disease diversity
  186. Deacylation and palmitoylation of lipid A by Salmonellae outer membrane enzymes modulate host signaling through Toll-like receptor 4
  187. Factors affecting the escape of Francisella tularensis from the phagolysosome
  188. Respiratory epithelial cells regulate lung inflammation in response to inhaled endotoxin
  189. Variation in lipid A structure in the pathogenic yersiniae
  190. 3- O -Deacylation of Lipid A by PagL, a PhoP/PhoQ-regulated Deacylase of Salmonella typhimurium , Modulates Signaling through Toll-like Receptor 4
  191. PmrAB, a Two-Component Regulatory System of Pseudomonas aeruginosa That Modulates Resistance to Cationic Antimicrobial Peptides and Addition of Aminoarabinose to Lipid A
  192. Pseudomonas aeruginosa lipid A diversity and its recognition by Toll-like receptor 4
  193. Genome mosaicism is conserved but not unique inPseudomonas aeruginosaisolates from the airways of young children with cystic fibrosis
  194. Proteomic analysis of Pseudomonas aeruginosa grown under magnesium limitation
  195. Macrophages from High-Risk HLA-DQB1*0201/*0302 Type 1 Diabetes Mellitus Patients are Hypersensitive to Lipopolysaccharide Stimulation
  196. mig-14 Is a Salmonella Gene That Plays a Role in Bacterial Resistance to Antimicrobial Peptides
  197. Salmonella typhimurium outer membrane remodeling: role in resistance to host innate immunity
  198. Carrier-mediated enhancement of cognate T cell help: the basis for enhanced immunogenicity of meningococcal outer membrane protein polysaccharide conjugate vaccine
  199. Genetic and Functional Analysis of a PmrA-PmrB-Regulated Locus Necessary for Lipopolysaccharide Modification, Antimicrobial Peptide Resistance, and Oral Virulence of Salmonella entericaSerovar Typhimurium
  200. Salmonella enterica Serovar TyphimuriumwaaP Mutants Show Increased Susceptibility to Polymyxin and Loss of Virulence In Vivo
  201. Constitutive Mutations of the Salmonella entericaSerovar Typhimurium Transcriptional Virulence RegulatorphoP
  202. Peptides, Pseudomonas aeruginosa, polysaccharides and lipopolysaccharides – players in the predicament of cystic fibrosis patients: Response
  203. Specific Lipopolysaccharide Found in Cystic Fibrosis Airway Pseudomonas aeruginosa
  204. How Intracellular Bacteria Survive: Surface Modifications That Promote Resistance to Host Innate Immune Responses
  205. The constitutive transport element (CTE) of Mason-Pfizer monkey virus (MPMV) accesses a cellular mRNA export pathway
  206. A structured retroviral RNA element that mediates nucleocytoplasmic export of intron-containing RNA.
  207. Concanavalin A Promotes Adherence of Salmonella typhimurium to Small Intestinal Mucosa of Rats