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Scientific Reports Jun 2024The COVID-19 pandemic has altered the infection landscape for many pathogens. This retrospective study aimed to compare Haemophilus influenzae (H. influenzae) infections...
The COVID-19 pandemic has altered the infection landscape for many pathogens. This retrospective study aimed to compare Haemophilus influenzae (H. influenzae) infections in pediatric CAP patients hospitalized before (2018-2019) and during (2020-2022) the COVID-19 pandemic. We analyzed the clinical epidemiology and antimicrobial resistance (AMR) patterns of H. influenzae from a tertiary hospital in southwest China. A total of 986 pediatric CAP patients with H. influenzae-associated infections were included. Compared to 2018, the positivity rate increased in 2019 but dropped significantly in 2020. Although it rose in the following 2 years, the rate in 2022 remained significantly lower than in 2019. Patients' age during the pandemic was significantly higher than in 2018 and 2019, while gender composition remained similar across both periods. Notably, there were significant changes in co-infections with several respiratory pathogens during the pandemic. Resistance rates of H. influenzae isolates to antibiotics varied, with the highest resistance observed for ampicillin (85.9%) and the lowest for cefotaxime (0.0%). Resistance profiles to various antibiotics underwent dramatic changes during the COVID-19 pandemic. Resistance to amoxicillin-clavulanate, cefaclor, cefuroxime, trimethoprim-sulfamethoxazole, and the proportion of multi-drug resistant (MDR) isolates significantly decreased. Additionally, MDR isolates, alongside isolates resistant to specific drugs, were notably prevalent in ampicillin-resistant and β-lactamase-positive isolates. The number of pediatric CAP patients, H. influenzae infections, and isolates resistant to certain antibiotics exhibited seasonal patterns, peaking in the winter of 2018 and 2019. During the COVID-19 pandemic, sharp decreases were observed in February 2020, and there was no resurgence in December 2022. These findings indicate that the COVID-19 pandemic has significantly altered the infection spectrum of H. influenzae in pediatric CAP patients, as evidenced by shifts in positivity rate, demographic characteristics, respiratory co-infections, AMR patterns, and seasonal trends.
Topics: Humans; COVID-19; Male; Female; Haemophilus influenzae; Child; Child, Preschool; Haemophilus Infections; Retrospective Studies; Community-Acquired Infections; Infant; China; Anti-Bacterial Agents; Hospitalization; Adolescent; Pandemics; Coinfection; SARS-CoV-2; Drug Resistance, Bacterial
PubMed: 38830922
DOI: 10.1038/s41598-024-62728-2 -
The Canadian Veterinary Journal = La... Jun 2024
Topics: Animals; Swine Diseases; Swine; Quebec; Streptococcus suis; Serogroup; Streptococcal Infections; Actinobacillus pleuropneumoniae; Actinobacillus Infections
PubMed: 38827588
DOI: No ID Found -
PLoS Neglected Tropical Diseases May 2024Haemophilus ducreyi was historically known as the causative agent of chancroid, a sexually-transmitted disease causing painful genital ulcers endemic in many...
Haemophilus ducreyi was historically known as the causative agent of chancroid, a sexually-transmitted disease causing painful genital ulcers endemic in many low/middle-income nations. In recent years the species has been implicated as the causative agent of nongenital cutaneous ulcers affecting children of the South Pacific Islands and West African countries. Much is still unknown about the mechanism of H. ducreyi transmission in these areas, and recent studies have identified local insect species, namely flies, as potential transmission vectors. H. ducreyi DNA has been detected on the surface and in homogenates of fly species sampled from Lihir Island, Papua New Guinea. The current study develops a model system using Musca domestica, the common house fly, as a model organism to demonstrate proof of concept that flies are a potential vector for the transmission of viable H. ducreyi. Utilizing a green fluorescent protein (GFP)-tagged strain of H. ducreyi and three separate exposure methods, we detected the transmission of viable H. ducreyi by 86.11% ± 22.53% of flies sampled. Additionally, the duration of H. ducreyi viability was found to be directly related to the bacterial concentration, and transmission of H. ducreyi was largely undetectable within one hour of initial exposure. Push testing, Gram staining, and PCR were used to confirm the identity and presence of GFP colonies as H. ducreyi. This study confirms that flies are capable of mechanically transmitting viable H. ducreyi, illuminating the importance of investigating insects as vectors of cutaneous ulcerative diseases.
Topics: Animals; Houseflies; Haemophilus ducreyi; Chancroid; Papua New Guinea; Insect Vectors; Female; Male
PubMed: 38814945
DOI: 10.1371/journal.pntd.0012194 -
Virulence Dec 2024() is a bacterial pathogen responsible for a range of infections in humans and various animal hosts, causing significant economic losses in farming. Integrative and...
() is a bacterial pathogen responsible for a range of infections in humans and various animal hosts, causing significant economic losses in farming. Integrative and conjugative elements (ICEs) are important horizontal gene transfer elements, potentially enabling host bacteria to enhance adaptability by acquiring multiple functional genes. However, the understanding of ICEs in and their impact on the transmission of this pathogen remains limited. In this study, 42 poultry-sourced genomes obtained by high-throughput sequencing together with 393 publicly available genomes were used to analyse the horizontal transfer of ICEs. Eighty-two ICEs were identified in , including SXT/R391 and Tn916 subtypes, as well as three subtypes of ICE1056 family, with the latter being widely prevalent in and carrying multiple resistance genes. The correlations between insertion sequences and resistant genes in ICEs were also identified, and some ICEs introduced the carbapenem gene and the bleomycin gene to . Phylogenetic and collinearity analyses of these bioinformatics found that ICEs in were transmitted vertically and horizontally and have evolved with host specialization. These findings provide insight into the transmission and evolution mode of ICEs in and highlight the importance of understanding these elements for controlling the spread of antibiotic resistance.
Topics: Pasteurella multocida; Gene Transfer, Horizontal; Animals; Phylogeny; Pasteurella Infections; Genome, Bacterial; DNA Transposable Elements; Conjugation, Genetic; Evolution, Molecular; Poultry; Prevalence; High-Throughput Nucleotide Sequencing
PubMed: 38808732
DOI: 10.1080/21505594.2024.2359467 -
Veterinary Microbiology Jul 2024Glaesserella parasuis (G. parasuis) is a common Gram-negative commensal bacterium in the upper respiratory tract of swine that can cause Glässer's disease under stress...
Glaesserella parasuis (G. parasuis) is a common Gram-negative commensal bacterium in the upper respiratory tract of swine that can cause Glässer's disease under stress conditions. Pyroptosis is an important immune defence mechanism of the body that plays a crucial role in clearing pathogen infections and endogenous danger signals. This study aimed to investigate the mechanism of G. parasuis serotype 5 SQ (GPS5-SQ)-induced pyroptosis in swine tracheal epithelial cells (STECs). The results of the present study demonstrated that GPS5-SQ infection induces pyroptosis in STECs by enhancing the protein level of the N-terminal domain of gasdermin D (GSDMD-N) and activating the NOD-like receptor protein 3 (NLRP3) inflammasome. Furthermore, the levels of pyroptosis-related proteins, including GSDMD-N and cleaved caspase-1 were considerably decreased in STECs after the knockdown of retinoic acid inducible gene-I (RIG-I) and mitochondrial antiviral signaling protein (MAVS). These results indicated that GPS5-SQ might trigger pyroptosis through the activation of the RIG-I/MAVS/NLRP3 signaling pathway. More importantly, the reactive oxygen species (ROS) scavenger N-acetylcysteine (NAC) repressed the activation of the RIG-I/MAVS/NLRP3 signaling and rescued the decrease in Occludin and zonula occludens-1 (ZO-1) after GPS5-SQ infection. Overall, our findings show that GPS5-SQ can activate RIG-I/MAVS/NLRP3 signaling and destroy the integrity of the epithelial barrier by inducing ROS generation in STECs, shedding new light on G. parasuis pathogenesis.
Topics: Animals; Pyroptosis; Epithelial Cells; NLR Family, Pyrin Domain-Containing 3 Protein; Swine; Signal Transduction; Haemophilus parasuis; Trachea; Swine Diseases; Serogroup; Adaptor Proteins, Signal Transducing; Inflammasomes; DEAD Box Protein 58; Haemophilus Infections
PubMed: 38797057
DOI: 10.1016/j.vetmic.2024.110127 -
International Journal of Molecular... May 2024, a zoonotic pathogen that produces a 146-kDa modular toxin (PMT), causes progressive atrophic rhinitis with severe turbinate bone degradation in pigs. However, its...
, a zoonotic pathogen that produces a 146-kDa modular toxin (PMT), causes progressive atrophic rhinitis with severe turbinate bone degradation in pigs. However, its mechanism of cytotoxicity remains unclear. In this study, we expressed PMT, purified it in a prokaryotic expression system, and found that it killed PK15 cells. The host factor CXCL8 was significantly upregulated among the differentially expressed genes in a transcriptome sequencing analysis and qPCR verification. We constructed a CXCL8-knockout cell line with a CRISPR/Cas9 system and found that CXCL8 knockout significantly increased resistance to PMT-induced cell apoptosis. CXCL8 knockout impaired the cleavage efficiency of apoptosis-related proteins, including Caspase3, Caspase8, and PARP1, as demonstrated with Western blot. In conclusion, these findings establish that CXCL8 facilitates PMT-induced PK15 cell death, which involves apoptotic pathways; this observation documents that CXCL8 plays a key role in PMT-induced PK15 cell death.
Topics: Interleukin-8; Animals; Pasteurella multocida; Bacterial Toxins; Apoptosis; Swine; Bacterial Proteins; Cell Line; Caspase 8; Gene Knockout Techniques; CRISPR-Cas Systems
PubMed: 38791369
DOI: 10.3390/ijms25105330 -
International Journal of Molecular... May 2024The most common type of periodontal disease is chronic periodontitis, an inflammatory condition caused by pathogenic bacteria in subgingival plaque. The aim of our study...
The most common type of periodontal disease is chronic periodontitis, an inflammatory condition caused by pathogenic bacteria in subgingival plaque. The aim of our study was the development of a real-time PCR test as a diagnostic tool for the detection and differentiation of five periodontopathogenic bacteria, , , , , and , in patients with periodontitis. We compared the results of our in-house method with the micro-IDent semiquantitative commercially available test based on the PCR hybridization method. DNA was isolated from subgingival plaque samples taken from 50 patients and then analyzed by both methods. Comparing the results of the two methods, they show a specificity of 100% for all bacteria. The sensitivity for was 97.5%, for 96.88%, and for 95.24%. The sensitivity for and was 100%. The Spearman correlation factor of two different measurements was 0.976 for , 0.967 for , 0.949 for , 0.966 for , and 0.917 for . In conclusion, the in-house real-time PCR method developed in our laboratory can provide information about relative amount of five bacterial species present in subgingival plaque in patients with periodontitis. It is likely that such a test could be used in dental diagnostics in assessing the efficacy of any treatment to reduce the bacterial burden.
Topics: Humans; Real-Time Polymerase Chain Reaction; Periodontitis; Porphyromonas gingivalis; Aggregatibacter actinomycetemcomitans; Treponema denticola; Male; Female; Tannerella forsythia; Sensitivity and Specificity; Prevotella intermedia; Middle Aged; Adult; DNA, Bacterial; Dental Plaque; Bacteria
PubMed: 38791137
DOI: 10.3390/ijms25105097 -
BMJ Case Reports May 2024is a gram-negative coccobacillus that is commonly transmitted through animal bites including cats and dogs. The degree of infection can be worrisome in the...
is a gram-negative coccobacillus that is commonly transmitted through animal bites including cats and dogs. The degree of infection can be worrisome in the immunosuppressed population with a stark correlation in patients with cirrhosis. However, taking that population into account, only 13 cases of bacteraemia have been recorded with the majority of those cases having cirrhotic liver disease along with multiple comorbidities. Here, we present an elderly patient with only pertinent medical history of mixed hyperlipidaemia who presents after a mechanical fall with acute renal failure and septic shock secondary to bacteraemia.
Topics: Humans; Pasteurella Infections; Bacteremia; Pasteurella multocida; Male; Aged; Anti-Bacterial Agents; Shock, Septic; Acute Kidney Injury
PubMed: 38789270
DOI: 10.1136/bcr-2024-259681 -
Colloids and Surfaces. B, Biointerfaces Aug 2024Dental Implants are expected to possess both excellent osteointegration and antibacterial activity because poor osseointegration and infection are two major causes of...
Dental Implants are expected to possess both excellent osteointegration and antibacterial activity because poor osseointegration and infection are two major causes of titanium implant failure. In this study, we constructed layer-by-layer self-assembly films consisting of anionic casein phosphopeptides-amorphous calcium phosphate (CPP-ACP) and cationic poly (L-lysine) (PLL) on sandblasted and acid etched (SLA) titanium surfaces and evaluated their osseointegration and antibacterial performance in vitro and in vivo. The surface properties were examined, including microstructure, elemental composition, wettability, and Ca ion release. The impact the surfaces had on the adhesion, proliferation and differentiation abilities of MC3T3-E1 cells were investigated, as well as the material's antibacterial performance after exposure to the oral microorganisms such as Porphyromonas gingivalis (P. g) and Actinobacillus actinomycetemcomitans (A. a). For the in vivo studies, SLA and Ti (PLL/CA-3.0) implants were inserted into the extraction socket immediately after extracting the rabbit mandibular anterior teeth with or without exposure to mixed bacteria solution (P. g & A. a). Three rabbits in each group were sacrificed to collect samples at 2, 4, and 6 weeks of post-implantation, respectively. Radiographic and histomorphometry examinations were performed to evaluate the implant osseointegration. The modified titanium surfaces were successfully prepared and appeared as a compact nano-structure with high hydrophilicity. In particular, the Ti (PLL/CA-3.0) surface was able to continuously release Ca ions. From the in vitro and in vivo studies, the modified titanium surfaces expressed enhanced osteogenic and antibacterial properties. Hence, the PLL/CPP-ACP multilayer coating on titanium surfaces was constructed via a layer-by-layer self-assembly technology, possibly improving the biofunctionalization of Ti-based dental implants.
Topics: Titanium; Osseointegration; Animals; Polylysine; Surface Properties; Anti-Bacterial Agents; Mice; Dental Implants; Rabbits; Porphyromonas gingivalis; Caseins; Cell Proliferation; Aggregatibacter actinomycetemcomitans; Microbial Sensitivity Tests; Cell Adhesion; Cell Differentiation; Calcium Phosphates
PubMed: 38781846
DOI: 10.1016/j.colsurfb.2024.113966 -
Infection and Immunity Jun 2024causes the genital ulcer disease chancroid and painful cutaneous ulcers in children who live in the tropics. To acquire heme from the host, expresses a TonB-dependent...
causes the genital ulcer disease chancroid and painful cutaneous ulcers in children who live in the tropics. To acquire heme from the host, expresses a TonB-dependent hemoglobin receptor, HgbA, which is necessary and sufficient for to progress to the pustular stage of disease in a controlled human infection model. HgbA transports hemoglobin across the outer membrane; how heme is transported across the cytoplasmic membrane is unclear. In previous studies, transcripts encoding the YfeABCD heme transporter were upregulated in experimental lesions caused by in human volunteers, suggesting the latter may have a role in virulence. Here we constructed a double deletion mutant, 35000HPΔΔ, which exhibited growth defects relative to its parent 35000HP in media containing human hemoglobin as an iron source. Five human volunteers were inoculated at three sites on the skin overlying the deltoid with each strain. The results of the trial showed that papules formed at 100% (95% CI, 71.5, 100) at both 35000HP and 35000HPΔΔ-inoculated sites ( = 1.0). Pustules formed at 60% (95% CI, 25.9, 94.1) at parent-inoculated sites and 53% (95% CI, 18.3, 88.4) at mutant-inoculated sites ( = 0.79). Thus, the ABC transporter encoded by and was dispensable for virulence in humans. In the absence of YfeABCD, likely utilizes other periplasmic binding proteins and ABC-transporters such as HbpA, SapABCDF, and DppBCDF to shuttle heme from the periplasm into the cytoplasm, underscoring the importance of redundancy of such systems in gram-negative pathogens.
Topics: Haemophilus ducreyi; Humans; Chancroid; Bacterial Proteins; Virulence; Iron; Male; Adult; Heme
PubMed: 38780215
DOI: 10.1128/iai.00058-24