Journal:

Article Title: Genetic and Molecular Characterization of ?-Lactamase-Negative Ampicillin-Resistant Haemophilus influenzae with Unusually High Resistance to Ampicillin

doi: 10.1128/AAC.48.5.1630-1639.2004

Figure Lengend Snippet: Distribution of deduced amino acid substitutions in the transpeptidase region of PBP3 in BLNAR isolates of H. influenzae compared to the sequence of strain Rd

Article Snippet: Based on scanning electron microscopy, all of the BLNAR strains examined displayed the characteristic filamentous phenotype ( 6 ) of ftsI mutants (data not shown). table ft1 table-wrap mode="anchored" t5 TABLE 3. caption a7 Strain AA273 (Ser→Ala) AA350 (Asp→Asn) AA357 (Ser→Asn) AA377 (Met→Iso) AA436 (Val→Ala) AA443 (Thr→Ala) AA449 (Iso→Val) AA490 (Gly→Glu) AA502 (Ala→Val) AA511 (Val→Ala) AA517 (Arg→His) AA526 (Asn→Lys) {"type":"entrez-nucleotide","attrs":{"text":"A51907","term_id":"2304654"}} A51907 a 1311 * 1312 * * * 1316 * 1318 * * * 1360 * * 1365 * * 1368 * 1369 * * * * 1370 * * * * 1371 * * 1373 * * 49247 b * * 1176 c * * Open in a separate window a ATCC control strain Rd. b Strain 49247 designates the ATCC BLNAR control. c Clinical isolate 1176 is a beta-lactamase-positive amoxicillin-clavulanate-resistant strain.

Techniques: Sequencing

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Multiplex droplet digital PCR for the detection and quantitation of Streptococcus pneumoniae , Mycoplasma pneumoniae , and Haemophilus influenzae

doi: 10.3389/fcimb.2025.1548492

Figure Lengend Snippet: Establishment and optimization of the multiplex ddPCR assay for S. pneumoniae, M. pneumoniae and H. influenzae detection. (a) Schematic of the multiplex ddPCR assay. The detection procedure consists of a two-step method: nucleic acid extraction followed by ddPCR detection. After extracting nucleic acids from the samples, the process continues with droplet preparation, PCR amplification. Finally, the results were analyzed by observing the fluorescence droplet plot in the FAM, VIC and CY5 channels via a QX200 reader. The droplets that were positive are indicated in green ( S. pneumoniae ), pink ( M. pneumoniae ) and blue ( H. influenzae ), the negative droplets appeared gray. (b, c) Optimal concentrations of primers and probes were determined by the results of detection of mixing positive samples. Screening Principle: The optimal probe and primer concentrations were selected according to whether the positive droplets were distributed centrally and whether they could be differentiated from the negative droplets efficiently. The experiment was repeated three times for each concentration (means ± SD).

Article Snippet: Haemophilus influenzae , Reference strain (ATCC 49247) , Chui Yang Liu Hospital , 1 , P.

Techniques: Multiplex Assay, Extraction, Amplification, Fluorescence, Concentration Assay

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Multiplex droplet digital PCR for the detection and quantitation of Streptococcus pneumoniae , Mycoplasma pneumoniae , and Haemophilus influenzae

doi: 10.3389/fcimb.2025.1548492

Figure Lengend Snippet: The dynamic range of the ddPCR assay to detect S. pneumoniae, M. pneumoniae and H. influenzae DNA. (a, e, i) The 10-fold serial dilution of S. pneumoniae gDNA, M. pneumoniae DNA, H. influenzae gDNA were detected by the ddPCR; the green points, the pink points and the blue points represent the positive signal; Correlation analysis to determine the dynamic detection range. (b, f, j) The expected values (converted to log10) of S. pneumoniae gDNA, M. pneumoniae DNA, H. influenzae gDNA were plotted on the Y axis and ddPCR detected values (converted to log10) on the X axis to perform linear analysis. Data are representative of at least three repeated experiments for different concentrations of template DNA. (c, g, k) The 10-fold serial dilution of S. pneumoniae gDNA, M. pneumoniae DNA, H. influenzae gDNA were detected by the qPCR; (d, h, l) The expected values (converted to log10) of S. pneumoniae gDNA, M. pneumoniae DNA, H. influenzae gDNA were plotted on the Y axis and qPCR detected values (converted to log10) on the X axis to perform linear analysis. DNase/RNase-free water was used as the negative control. The experiment was repeated three times (means ± SD). **P < 0.01, ***P < 0.001, ****P < 0.0001. "n.s." indicates no statistically significant difference.

Article Snippet: Haemophilus influenzae , Reference strain (ATCC 49247) , Chui Yang Liu Hospital , 1 , P.

Techniques: Serial Dilution, Negative Control

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Multiplex droplet digital PCR for the detection and quantitation of Streptococcus pneumoniae , Mycoplasma pneumoniae , and Haemophilus influenzae

doi: 10.3389/fcimb.2025.1548492

Figure Lengend Snippet: Determining the LoD of the ddPCR assay. (a) The LoD for S. pneumoniae , M. pneumoniae , and H . influenzae in the multiplex qPCR assay was determined using probit analysis of sigmoid curves. Repeated ddPCR assays with different concentrations of S. pneumoniae , M. pneumoniae and H . influenzae DNA were performed near the detection limits determined in the pre-experiment. The X-axis represents the expected concentration, and the Y-axis represents the proportion of positive results in the same experiment. The blue line is the probit curve, and the red dashed line are 95% confidence interval (95% CI), the experiment was repeated six times for each concentration in the same parallel reactions. (b) The probit analysis sigmoid curve was used to determine the LoD of the multiplex qPCR for S. pneumoniae , M. pneumoniae and H . influenzae detection. The analytical method was the same as in (a) .

Article Snippet: Haemophilus influenzae , Reference strain (ATCC 49247) , Chui Yang Liu Hospital , 1 , P.

Techniques: Multiplex Assay, Concentration Assay

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Multiplex droplet digital PCR for the detection and quantitation of Streptococcus pneumoniae , Mycoplasma pneumoniae , and Haemophilus influenzae

doi: 10.3389/fcimb.2025.1548492

Figure Lengend Snippet: Specificity of the ddPCR assay to detect S. pneumoniae , M. pneumoniae and H . influenzae . 26 pathogenic bacteria were used to determine the specificity of the multiplex ddPCR. (a) VIC channel detection results. (b) CY5 channel detection results. (c) FAM channel detection results. S. pneumoniae (ATCC 49619), M. pneumoniae positive sample and H , influenzae (ATCC 49247) were used as the positive control strain. DNase-free water was used as negative control. The droplets that were positive were indicated in green ( S. pneumonia ), pink ( M. pneumoniae ) and blue ( H. influenzae ), the negative droplets appeared gray.

Article Snippet: Haemophilus influenzae , Reference strain (ATCC 49247) , Chui Yang Liu Hospital , 1 , P.

Techniques: Bacteria, Multiplex Assay, Positive Control, Negative Control

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Multiplex droplet digital PCR for the detection and quantitation of Streptococcus pneumoniae , Mycoplasma pneumoniae , and Haemophilus influenzae

doi: 10.3389/fcimb.2025.1548492

Figure Lengend Snippet: Comparison of the detection efficiency of qPCR, ddPCR and chip inspection in detection of S. pneumoniae , M. pneumoniae , H. influenzae in clinical samples. (a) The detection results of qPCR, ddPCR, bacterial culture or chip inspection in detection of S. pneumoniae , M. pneumoniae , H. influenzae in 167 clinical samples. (b) Correlation between qPCR and ddPCR. Samples that were detectable by both ddPCR and qPCR were analyzed. Event numbers for ddPCR are plotted on the x axis and the threshold cycle for qPCR on the y axis.

Article Snippet: Haemophilus influenzae , Reference strain (ATCC 49247) , Chui Yang Liu Hospital , 1 , P.

Techniques: Comparison

Journal: Frontiers in Cellular and Infection Microbiology

Article Title: Multiplex droplet digital PCR for the detection and quantitation of Streptococcus pneumoniae , Mycoplasma pneumoniae , and Haemophilus influenzae

doi: 10.3389/fcimb.2025.1548492

Figure Lengend Snippet: Evaluation of the interference resistance capability in ddPCR assay. (a) Evaluation of respiratory specimen extracts’ impact on quantitative detection of S. pneumoniae , M. pneumoniae and H. influenzae DNA by ddPCR and qPCR. Equal amounts of plasmid DNA were added to samples containing different amounts (2μL to 8μL) of extract of respiratory specimen to prepare spiked samples. Simultaneously prepare control samples (2μL to 8μL of DNase-free water and plasmid at the same concentration). Calculate and compare the inhibition rates using the ddPCR and qPCR results (CT values converted to copy numbers) and the control sample results (copy numbers). Inhibition rate (%) calculation formula: [(Control copy number – ddPCR/qPCR copy number)/Control copy number×100]. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001. (b) To observe the influence of a single high concentration pathogen on the detection of the other two pathogens in the co-infection detection. Sequentially: high-concentration samples of SP, MP, and HI. The droplets that were positive were indicated in green (SP), pink (MP) and blue (HI), the negative droplets appeared gray. SP, S. pneumoniae , MP, M. pneumoniae , HI, H. influenzae . "n.s." indicates no statistically significant difference.

Article Snippet: Haemophilus influenzae , Reference strain (ATCC 49247) , Chui Yang Liu Hospital , 1 , P.

Techniques: Plasmid Preparation, Control, Concentration Assay, Inhibition, Infection

Journal:

Article Title: Use of the National Committee for Clinical Laboratory Standards Guidelines for Disk Diffusion Susceptibility Testing in New York State Laboratories

doi:

Figure Lengend Snippet: Key to analysis of compliance with 1993 or 1997 NCCLS guidelines a for disk diffusion susceptibility testing

Article Snippet: Both ATCC 49247 and ATCC 49766 , , , , 29.2.

Techniques: Diffusion-based Assay, Incubation, Control

Journal:

Article Title: Use of the National Committee for Clinical Laboratory Standards Guidelines for Disk Diffusion Susceptibility Testing in New York State Laboratories

doi:

Figure Lengend Snippet: Responses and summary data for five key questions regarding specific protocols used by participating laboratories

Article Snippet: Both ATCC 49247 and ATCC 49766 , , , , 29.2.

Techniques: Suspension, Chocolate, Incubation, Control