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Biochemical and Biophysical Research... Mar 2022L-enantiomers of antimicrobial peptides (AMPs) are sensitive to proteolytic degradation; however, D-enantiomers of AMPs are expected to provide improved proteolytic... (Comparative Study)
Comparative Study
L-enantiomers of antimicrobial peptides (AMPs) are sensitive to proteolytic degradation; however, D-enantiomers of AMPs are expected to provide improved proteolytic resistance. The present study aimed to comparatively investigate the in vitro antibacterial activity, trypsin and serum stability, toxicity, and in vivo antibacterial activity of L-enantiomeric bovine NK2A (L-NK2A) and its D-enantiomeric NK2A (D-NK2A). Circular dichroism spectroscopy of D-NK2A and L-NK2A in anionic liposomes showed α-helical structures and the α-helical conformation of D-NK2A was a mirror image of L-NK2A. Both D-NK2A and L-NK2A displayed minimal in vitro and in vivo toxicities. RP-HPLC and mass spectrometry analyses revealed that D-NK2A, but not L-NK2A, was resistant to trypsin digestion. D-NK2A and L-NK2A showed similar in vitro bacterial killing activities against Histophilus somni. Slightly reduced antibacterial activity was observed when D-NK2A and L-NK2A were pre-incubated with serum. Confocal and transmission electron microscopic findings confirmed that both peptides induced disruption of bacterial inner- and outer-membranes. Improved survivals with D-NK2A treatment were observed when compared to L-NK2A in a murine model of acute H. somni septicemia. We conclude that antibacterial activity and mode of action of NK2A are not chiral specific. With further optimization, D-NK2A may be a viable AMP candidate to combat bacterial infections.
Topics: Animals; Anti-Bacterial Agents; Antimicrobial Peptides; Cattle; Circular Dichroism; Kaplan-Meier Estimate; Mice; Microscopy, Electron, Transmission; Pasteurellaceae; Pasteurellaceae Infections; Protein Stability; Protein Structure, Secondary; Proteolipids; Stereoisomerism
PubMed: 35101666
DOI: 10.1016/j.bbrc.2022.01.071 -
FEBS Open Bio Dec 2022Nontypeable Haemophilus influenzae (NTHi) has emerged as a dominant mucosal pathogen causing acute otitis media (AOM) in children, acute sinusitis in children and...
Nontypeable Haemophilus influenzae (NTHi) has emerged as a dominant mucosal pathogen causing acute otitis media (AOM) in children, acute sinusitis in children and adults, and acute exacerbations of chronic bronchitis in adults. Consequently, there is an urgent need to develop a vaccine to protect against NTHi infection. A multi-component vaccine will be desirable to avoid emergence of strains expressing modified proteins allowing vaccine escape. Protein D (PD), outer membrane protein (OMP) 26, and Protein 6 (P6) are leading protein vaccine candidates against NTHi. In pre-clinical research using mouse models, we found that recombinantly expressed PD, OMP26, and P6 induce robust antibody responses after vaccination as individual vaccines, but when PD and OMP26 were combined into a single vaccine formulation, PD antibody levels were significantly lower. We postulated that PD and OMP26 physiochemically interacted to mask PD antigenic epitopes resulting in the observed effect on antibody response. However, column chromatography and mass spectrometry analysis did not support our hypothesis. We postulated that the effect might be in vivo through the mechanism of protein vaccine immunologic antigenic competition. We found when PD and OMP26 were injected into the same leg or separate legs of mice, so that antigens were immunologically processed at the same or different regional lymph nodes, respectively, antibody levels to PD were significantly lower with same leg vaccination. Different leg vaccination produced PD antibody levels quantitatively similar to vaccination with PD alone. We conclude that mixing PD and OMP26 into a single vaccine formulation requires further formulation studies.
Topics: Mice; Animals; Haemophilus Vaccines; Bacterial Outer Membrane Proteins; Antibodies, Bacterial; Immunoglobulin G; Haemophilus influenzae
PubMed: 36263849
DOI: 10.1002/2211-5463.13498 -
Journal of Periodontology Nov 2020The 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions grouped the diseases previously recognized as chronic (CP) or... (Review)
Review
BACKGROUND
The 2017 World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions grouped the diseases previously recognized as chronic (CP) or aggressive (AgP) periodontitis under a single category named periodontitis. The rationale for this decision was the lack of specific patterns of immune-inflammatory response or microbial profiles associated with CP or AgP. However, no previous studies have compiled the results of all studies comparing subgingival microbial data between these clinical conditions. Thus, this systematic review aimed to answer the following focused question: "Do patients with AgP periodontitis present differences in the subgingival microbiota when compared with patients with CP?"
METHODS
A systematic review was conducted according to the PRISMA statement. The MEDLINE, EMBASE, and Cochrane databases were searched up to June 2019 for studies of any design (except case reports, case series, and reviews) comparing subgingival microbial data from patients with CP and AgP.
RESULTS
A total of 488 articles were identified and 56 were included. Thirteen studies found Aggregatibacter actinomycetemcomitans elevated in AgP in comparison with CP, while Fusobacterium nucleatum, Parvimonas micra, and Campylobacter rectus were elevated in AgP in a few studies. None of these species were elevated in CP. However, the number of studies not showing statistically significant differences between CP and AgP was always higher than that of studies showing differences.
CONCLUSION
These results suggested an association of A. actinomycetemcomitans with AgP, but neither this species nor the other species studied to date were unique to or could differentiate between CP and AgP (PROSPERO #CRD42016039385).
Topics: Aggregatibacter actinomycetemcomitans; Aggressive Periodontitis; Chronic Periodontitis; Dental Plaque; Firmicutes; Humans; Porphyromonas gingivalis
PubMed: 32233092
DOI: 10.1002/JPER.19-0586 -
Clinical Infectious Diseases : An... Nov 2021Since the introduction of Haemophilus influenzae serotype b (Hib) conjugate vaccines in the United States, invasive H. influenzae disease epidemiology has changed, and...
BACKGROUND
Since the introduction of Haemophilus influenzae serotype b (Hib) conjugate vaccines in the United States, invasive H. influenzae disease epidemiology has changed, and racial disparities have not been recently described.
METHODS
Active population- and laboratory-based surveillance for H. influenzae was conducted through Active Bacterial Core surveillance at 10 US sites. Data from 2008-2017 were used to estimate projected nationwide annual incidence, as cases per 100 000.
RESULTS
During 2008-2017, Active Bacterial Core surveillance identified 7379 H. influenzae cases. Of 6705 patients (90.9%) with reported race, 76.2% were White, 18.6% were Black, 2.8% were Asian/Pacific Islander, and 2.4% were American Indian or Alaska Native (AI/AN). The nationwide annual incidence was 1.8 cases/100 000. By race, incidence was highest among AI/AN populations (3.1) and lowest among Asian/Pacific Islander populations (0.8). Nontypeable H. influenzae caused the largest incidence within all races (1.3), with no striking disparities identified. Among AI/AN children aged <5 years, incidence of H. influenzae serotype a (Hia) was 16.7 times higher and Hib incidence was 22.4 times higher than among White children. Although Hia incidence was lower among White and Black populations than among AI/AN populations, Hia incidence increased 13.6% annually among White children and 40.4% annually among Black children aged <5 years.
CONCLUSIONS
While nontypeable H. influenzae causes the largest H. influenzae burden overall, AI/AN populations experience disproportionately high rates of Hia and Hib, with the greatest disparity among AI/AN children aged <5 years. Prevention tools are needed to reduce disparities affecting AI/AN children and address increasing Hia incidence in other communities.
Topics: Child; Haemophilus Infections; Haemophilus Vaccines; Haemophilus influenzae; Haemophilus influenzae type b; Humans; Incidence; Infant; Serogroup; United States
PubMed: 33993217
DOI: 10.1093/cid/ciab449 -
Infectious Diseases Now Jun 2022We report for the first time the association of Haemophilus pittmaniae and Haemophilus sputorum with urethritis in men who have sex with men and who engage in...
BACKGROUND
We report for the first time the association of Haemophilus pittmaniae and Haemophilus sputorum with urethritis in men who have sex with men and who engage in unprotected intercourse.
PATIENTS AND METHODS
A search for genital pathogens was conducted using urethral exudate cultures and PCR tests for Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Mycoplasma spp., and Ureaplasma spp. Recovered microorganisms were identified by MALDI-TOF mass spectrometry, and their susceptibility was evaluated by diffusion gradient test.
RESULTS
H. pittmaniae and H. sputorum were isolated. They both proved susceptible to ampicillin, cefixime, and trimethoprim/sulfamethoxazole. H. pittmaniae was also susceptible to tetracycline and H. sputorum to moxifloxacin.
CONCLUSION
The increased frequency of potentially resistant Haemophilus spp. isolates in genital exudates highlights the need for greater surveillance of these microorganisms and for their consideration in the differential diagnosis of genital system infections.
Topics: Genitalia; Haemophilus; Homosexuality, Male; Humans; Male; Sexual and Gender Minorities; Urinary Tract Infections
PubMed: 35483632
DOI: 10.1016/j.idnow.2022.04.003 -
TheScientificWorldJournal 2024species are frequently encountered as serious diseases in small ruminants. It is the main cause of respiratory pasteurellosis in sheep and goats of all age groups.
BACKGROUND
species are frequently encountered as serious diseases in small ruminants. It is the main cause of respiratory pasteurellosis in sheep and goats of all age groups.
METHODS
The cross-sectional study was conducted from December 2022 to April 2023 in Haramaya district, eastern Ethiopia, to isolate and identify and and estimate their prevalence, associated risk factors, and antimicrobial sensitivity of isolates in small ruminants using a purposive sampling method. A total of 384 samples (156 nasal swabs from clinic cases and 228 lung swabs from abattoir cases) were collected. STATA 14 software was used to analyze the data. In addition, multivariable logistic regression analysis was performed to assess an association of risk factors.
RESULTS
Out of the 384 samples examined, 164 were positive for pasteurellosis, resulting in a 42.70% prevalence. Similarly, 63 (38.4%) of the 164 positive results were from nasal swabs, while 101 (61.6%) came from lung samples. accounted for 126 (76.82%) of the isolates, while accounted for 38 (23.17%). Of the 63 nasal swab isolates, 33 (37%) were from goats and 30 (42.8%) were from sheep. And 17 (10.89%) and 46 (29.58%), respectively, were and . Of the 46 (40%) of the 101 (44.3%) isolates of the pneumonic lung, samples were from goats, while 55 (48.47%) were from sheep. In this study, the risk factors (species, age, and body condition score) were found to be significant ( < 0.05). isolates evaluated for antibiotic susceptibility were highly resistant to oxacillin (90.90%), followed by gentamycin (72.72%), and penicillin (63.63%). However, the isolates were highly sensitive to chloramphenicol (90.90%), followed by tetracycline (63.63%), and ampicillin (54.54%).
CONCLUSION
This study showed that and are the common causes of mannheimiosis and pasteurellosis in small ruminants, respectively, and isolates were resistant to commonly used antibiotics in the study area. Thus, an integrated vaccination strategy, antimicrobial resistance monitoring, and avoidance of stress-inducing factors are recommended.
Topics: Animals; Pasteurella multocida; Mannheimia haemolytica; Ethiopia; Sheep; Goats; Anti-Bacterial Agents; Cross-Sectional Studies; Microbial Sensitivity Tests; Sheep Diseases; Goat Diseases; Prevalence; Risk Factors; Pasteurella Infections
PubMed: 38655561
DOI: 10.1155/2024/5605552 -
Sultan Qaboos University Medical Journal Aug 2023Empyema can rarely complicate pneumonia in neonates; it has a high morbidity and mortality in this population. We report a two-month-old healthy term male neonate who...
Empyema can rarely complicate pneumonia in neonates; it has a high morbidity and mortality in this population. We report a two-month-old healthy term male neonate who presented with fever, mild shortness of breath and reduced feeding to a tertiary care hospital in Muscat, Oman, in 2021. Investigations revealed the presence of Haemophilus influenzae empyema. He was managed with video-assisted thoracoscopic surgery and prolonged course of antibiotics. A follow-up at the end of the antibiotic course revealed complete symptom resolution with a repeated chest x-ray showing significant right chest opacity improvement. A baseline immune work-up was done and was reported to be within normal ranges.
Topics: Infant, Newborn; Humans; Infant; Male; Anti-Bacterial Agents; Empyema; Fever; Haemophilus influenzae; Oman
PubMed: 37655094
DOI: 10.18295/squmj.5.2022.041 -
Journal of Global Antimicrobial... Dec 2023The aim of this study was to characterize the floR-carrying plasmids originating from Glaesserella parasuis and Actinobacillus indolicus isolated from pigs with...
OBJECTIVES
The aim of this study was to characterize the floR-carrying plasmids originating from Glaesserella parasuis and Actinobacillus indolicus isolated from pigs with respiratory disease in China.
METHODS
A total of 125 G. parasuis and 28 A. indolicus strains collected between 2009 and 2022 were screened for florfenicol resistance. Characterization of floR-positive isolates and plasmids were determined by antimicrobial susceptibility testing, serotyping, multilocus sequence typing (MLST), conjugation and transformation assays, whole-genome sequencing (WGS), and phylogenetic analysis.
RESULTS
One A. indolicus and six G. parasuis were identified as positive for floR. The six G. parasuis were assigned to four different serovars, including serovars 6, 7, 9, and unknown. In addition to strain XP11, six floR genes were located on plasmids. The six floR-bearing plasmids could be transformed into Pasteurella multocida and divided into two different types, including ∼5000 bp and ∼6000 bp plasmids. The ∼5000 bp plasmids consisting of rep, lysR, mobB, and floR genes, exhibited high similarity among Pasteurellaceae bacteria. Furthermore, the ∼6000 bp plasmids, consisting of rep, lysR, mobC, mobA/L, and floR genes, showed high similarity between G. parasuis and Actinobacillus Spp. Notably, WGS results showed that the floR modules of the two types of plasmids could be transferred and integrated into the diverse Pasteurellaceae- origined plasmids.
CONCLUSION
This study firstly reported the characterization of floR-carrying plasmids from A. indolicus and a non-virulent serovar of G. parasuis in pigs in China and elucidated the transmission mechanism of the floR resistance gene among the Pasteurellaceae family.
Topics: Animals; Swine; Anti-Bacterial Agents; Multilocus Sequence Typing; Phylogeny; Plasmids; Actinobacillus
PubMed: 37726088
DOI: 10.1016/j.jgar.2023.09.009 -
American Journal of Orthodontics and... Mar 2022Patients with dental crowding, even with good oral hygiene, may show increased bacterial presence in the crowded area. This study aimed to determine the microbial...
INTRODUCTION
Patients with dental crowding, even with good oral hygiene, may show increased bacterial presence in the crowded area. This study aimed to determine the microbial composition of subgingival plaque in crowded and noncrowded dental regions.
METHODS
Forty dental students with anterior dental crowding, who were aware of correct brushing techniques and oral hygiene, were enrolled in this study. After orthodontic records were taken and the periodontal examination was performed, subgingival plaque samples were collected from the crowded (experimental) and noncrowded regions (control) of each patient. Colony counting was performed for Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and streptococcus species.
RESULTS
The mean amount of Aa and Pg colonies was significantly higher in crowded areas (P <0.0001), but there was no significant difference between streptococcus species colonization and crowding. Aa and Pg colonization had a significant direct relation with the amount of crowding. (P <0.0001).
CONCLUSIONS
Crowded dental areas, even with good oral hygiene, are more suitable environments for Aa and Pg colonization.
Topics: Aggregatibacter actinomycetemcomitans; Dental Plaque; Humans; Malocclusion; Porphyromonas gingivalis; Toothbrushing
PubMed: 34688519
DOI: 10.1016/j.ajodo.2020.09.029 -
Georgian Medical News Jun 2021The study is aimd at detection the pathogenic markers: Aggregatibacter actinomycetemcomit, Porphyromonas Gingivalis, Prevotella Intermedia, Tannerella Forsythia and...
The study is aimd at detection the pathogenic markers: Aggregatibacter actinomycetemcomit, Porphyromonas Gingivalis, Prevotella Intermedia, Tannerella Forsythia and Treponema Denticola, identify their types, qualitative content and encounter frequency in periodontal pockets of the patients with generalized periodontitis, stage II (A or B level), before and after treatment with mechanical forms of therapy - Ultrasound, Vector or Laser Therapy . The material has been studied by using Micro-Ident biological method based on DNA-Strip technology. The surveyed 25 patients (women - 75% and men - 25%), 20 to 60 years of age, were divided into the three groups: group I treatment with Ultrasound scaler (n=9), group II treatment with Ultrasound Scaler and Diode laser (n=8), group III treatment with Ultrasound Scaler and Vector Sistem (n=8). All five strain before treatment were detected in 3 (12.5%) cases, none of the strain were detected in 1 patient (4%); among the rest 21 patients (87.5%) the following associations of different microorganisms were detected: P.G., P.I, T.F., T.D. - in 20.8% of patients, P.G., T.F., T.D. - 12.5%; A.A., P.G., P.I., T.F. - 4.16%; P.G., P.I., T.F.-33.28%; P.I., T.F., T.D. - 4.16%; A.A., P.G., T.F., T.D. - 12.5%; P.I., T.F. - 4.16%; P.G., P.I., T.D. - 4.16%. After evaluating the effectiveness of the treatment, based on Ultrasound system, Vector system, Diode laser and the complex picture of clinical and laboratory examinations in patients with generalized periodontitis, stage II, A or B level, a significant improvement in clinical conditions was observed. The microbiological study of Aggregatibacter Actinomycetemcomit (AA), Porphyromonas Gingivalis (PG), Prevotella Intermidia (PI), Tannerella Forsythia (BF), Treponema Denticola (TD) showed a complete elimination of qualitative and quantitative data after Vector therapy, but no reliable elimination of bacteria was observed after ultrasound and laser therapies. After treatment all five strain were detected in 1 (4%) case, 4 strain A.A., P.G., T.F., T.D. in 1 (4%) case, P.G.,P.I.,T.F.,T.D. - 2 (8%) case, 3 strain P.G., P.I., T.F in 3 (12.5%) case, 2 strain P.G., T.F - 1 strain (4%) and 1 T.F in 2 (8%).
Topics: Aggregatibacter actinomycetemcomitans; Bacteroides; Female; Humans; Male; Periodontal Pocket; Prevotella intermedia; Treponema denticola
PubMed: 34365426
DOI: No ID Found