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Antibiotics (Basel, Switzerland) Nov 2023A total of seventy VanA-type vancomycin-resistant enterococci (VRE) isolates obtained in Taiwan in the early 2000s were retrospectively characterized. Forty isolates...
A total of seventy VanA-type vancomycin-resistant enterococci (VRE) isolates obtained in Taiwan in the early 2000s were retrospectively characterized. Forty isolates were obtained from human patients and thirty from livestock. Of these VRE isolates, twenty-three (57.5%) of the human VRE and thirty (100%) of the livestock VRE were , and the remaining seventeen (42.5%) of the human VRE were . Of the 53 isolates, twenty-two (96%) of the human VRE and thirty (100%) of the livestock VRE exhibited a high level of resistance to vancomycin and sensitivity to teicoplanin. They also had three amino acid substitutions in the N-terminal region of the deduced VanS sequence. The vancomycin resistance of all of the 22 human isolates, and 20 of the 30 livestock isolates, transferred to FA2-2 at a frequency of 10 to 10 per donor cell in broth. Each of the transconjugants responded to pheromone (i.e., FA2-2 culture filtrate), indicating that the conjugative plasmids were pheromone-responsive plasmids. Three of the conjugative plasmids originated from human isolates, and five plasmids from livestock isolates were corresponded and classified as type A plasmid. Two plasmids originated from human isolates and six plasmids from livestock isolates were corresponded and classified as type B plasmid. FA2-2 containing either the type A or type B plasmid responded to the synthetic pheromone cAD1. The type A and type B plasmids transferred between FA2-2 and JH2SS at a frequency of about 10 per donor cell and conferred vancomycin, bacitracin, and erythromycin resistances. The complete DNA sequence of the representative type A plasmid pTW9 (85,068 bp) showed that the plasmid carried a Tn-like element encoding -type resistance, erythromycin resistance (), and bacitracin resistance (). The plasmid contained the regulatory region found in the pheromone-responsive plasmid and encoded the genes , and , which are the key negative regulatory elements, and , a key positive regulator of plasmid pAD1, indicating that plasmid pTW9 was pAD1-type pheromone-responsive plasmid. PFGE analysis of SmaI-digested chromosomal DNAs showed that several strains harboring an identical type A pheromone-responsive plasmid were indistinguishable, and that these were identified both in human and livestock isolates, indicating the transmissions of the VRE strains between livestock and humans. These data showed that the multiple-drug-resistant pheromone-responsive conjugative plasmids have been widely spread in both human and livestock VRE, and there was high potential for transfers of VRE from food animals to humans in Taiwan in the early 2000s.
PubMed: 38136702
DOI: 10.3390/antibiotics12121668 -
Frontiers in Microbiology 2023Many research studies focus on intestinal microbiota-related depression induced by the usage of antibiotics, but the use of antibiotics is fairly different. To construct...
Many research studies focus on intestinal microbiota-related depression induced by the usage of antibiotics, but the use of antibiotics is fairly different. To construct an effective antibiotic-induced depression mice model and explore the effect of intestinal microbiota in antibiotic-induced depression, we used several kinds of antibiotic mixtures to induce mice depression and used depression-related behavioral tests and neurobiological factors to evaluate the construction of the antibiotic-induced depression mice model. SPSS statistical software was used to analyze the above data, and the optimal model was selected according to the stability of the results and the simplicity of the modeling methods. Metagenomic analysis and fecal microbiota transplantation (FMT) of intestinal microbiota from antibiotic-induced depression mice were performed to analyze the effect of intestinal microbiota. The results showed that antibiotic mixture A (1.25 μg/mL natamycin, 5 mg/mL neomycin sulfate, and 5 mg/mL bacitracin), antibiotic mixture B (24 mg/mL bacitracin, 24 mg/mL neomycin sulfate, 9.6 mg/mL ampicillin, 4.8 mg/mL meropenem, and 1.47 mg/mL vancomycin), and antibiotic solution D (only containing 5 mg/mL neomycin sulfate) could induce depression-like behavior in mice. By using these antibiotics, the concentrations of norepinephrine (NE), 5-hydroxytryptamine (5-HT), and brain-derived neurotrophic factor (BDNF) in mice hippocampus and prefrontal cortex tissues were significantly decreased. All the above results were consistent with those of chronic unpredictable mild stress (CUMS) depression mice. The FMT results showed that fecal microbiota from antibiotic-induced depressed mice transplanted into normal mice (8 weeks-old male C57BL/6J SPF mice) also could induce depression-like behavior and cause similar changes in neurobiological factors. Metagenomic analysis showed that the community structure of microbiota in the intestinal tract of antibiotic-induced depression mice was significantly different from that in control mice, the intestinal microbiota species diversity in antibiotic-induced depression mice was lower, the lipoic acid metabolism pathway was significantly activated, and the abundance of functional gene was explicitly increased. Quantitative real-time PCR (qPCR) further verified the abundance of enriched bacteria in the intestinal microbiota of antibiotic-induced depression mice. In summary, the specific antibiotic mixtures can induce depression by causing changes in intestinal microbiota in mice. Antibiotic-induced depressed mice show differences in intestinal microbiota abundance, high enrichment of the unique metabolic pathway, and the functional gene.
PubMed: 38088959
DOI: 10.3389/fmicb.2023.1093486 -
International Journal of Clinical... Sep 2023Full-coverage restorations are commonly employed choice of treatment in treating multisurface carious lesions in primary teeth.
BACKGROUND
Full-coverage restorations are commonly employed choice of treatment in treating multisurface carious lesions in primary teeth.
AIM
To assess the amount of colonization and oral hygiene status in deciduous molars restored with preformed zirconia and stainless steel crowns (SSC).
MATERIALS AND METHODS
A total of 21 children aged between 4 and 7 years with bilateral carious primary molars were randomly divided into two groups of zirconia and SSC. Plaque collection was done using sterile swabs at baseline and 1-month intervals. was cultured on mitis salivariusbacitracin agar (MSBA). The microorganisms were then counted and expressed as colony-forming units. The plaque and gingival indices were recorded during the follow-up visits. All data were tabulated and subjected to statistical analysis, with the level of significance set at 5%.
RESULTS
A total of 21 children with 42 teeth were randomized into group I-SSC and group II-zirconia crowns using the split-mouth technique, respectively. The zirconia group showed a statistically significant reduction in the adhesion of ( < 0.001). On comparing the plaque and gingival indices between the groups, plaque index (PI) and gingival index (GI) scores were significantly low in the zirconia group as compared with the SSC, with a mean difference of 0.08 at 3 months in group II ( < 0.001).
CONCLUSION
adhesion to zirconia crowns was significantly less when compared with SSC, with better gingival health and oral hygiene.
HOW TO CITE THIS ARTICLE
Elizabeth JAA, Ramkumar H, Paulindraraj S, Evaluation of Colonization and Oral Hygiene Status in Primary Molars Restored with Two Different Crowns: A Randomized Clinical Trial. Int J Clin Pediatr Dent 2023;16(S-2):S183-S189.
PubMed: 38078038
DOI: 10.5005/jp-journals-10005-2650 -
Journal of Oral and Maxillofacial... 2023Worldwide, dental caries is an endemic infection and a significant public health problem. Fluoride reduces caries by helping to prevent demineralisation, by...
BACKGROUND AND OBJECTIVE
Worldwide, dental caries is an endemic infection and a significant public health problem. Fluoride reduces caries by helping to prevent demineralisation, by remineralising early carious lesions, and by decreasing the activity and growth of . Fluoride intake above the optimal levels leads to a condition known as dental fluorosis, which causes hypo-mineralisation of the tooth. Some studies have revealed that the severity of fluorosis is directly proportional to caries, but some showed opposite results. Hence, with these contradicting results, this study was undertaken to identify the relationship between different grades of dental fluorosis, dental caries and the most common cariogenic bacteria . in saliva.
MATERIALS AND METHODS
A total of 90 subjects within 14- to 16-year age range were selected and categorised depending on the severity of fluorosis into three groups: group I (mild), group II (moderate) and group III (severe) based on modified Dean's fluorosis index criteria (1942). Unstimulated whole saliva samples were collected using the oral rinse technique and processed for quantification of . using Mitis Salivarius Bacitracin Agar medium. The number of colony-forming units (CFUs) was determined using a colony counter and expressed as ≥10, ≥10, ≥10 and ≥10 CFUs per ml of the sample, in accordance with the scale recommended by the manufacturer (HiMedia Laboratories). The severity of the caries was measured using decayed, missing or filled teeth (DMFT).
RESULTS
Observations revealed that the overall DMFT was directly proportional to the level of titres. It was observed that 67 to 73% of participants showed fewer colony counts (10 and 10) with minimal DMFT scores and 27 to 33% showed higher counts (10 and 10) with higher DMFT scores in all the groups. 10 CFUs of group III showed the highest mean DMFT scores (2.9) with an increased number of involved subjects than group II (2.3) and group I (1.5). In all, male participants had higher bacterial titres and DMFT scores than females.
CONCLUSION
Fluoride in the drinking water served as anticariogenic agent regardless of the severity of fluorosis. Severe fluorosis with a higher incidence of caries and increased CFUs of S. clearly indicates the importance of preventive measures and early treatment to reduce the severity of fluorosis and prevalence of dental caries.
PubMed: 38033974
DOI: 10.4103/jomfp.jomfp_59_23 -
Veterinaria Italiana Nov 2023Bovine mastitis is a multifactorial disease, caused mainly by bacteria, whose most traditional method of treatment is the use of antibiotics. However, incorrect...
Bovine mastitis is a multifactorial disease, caused mainly by bacteria, whose most traditional method of treatment is the use of antibiotics. However, incorrect administration of these drugs may lead to the emergence of resistant strains. The objective of this study was to identify the most common pathogens causing subclinical mastitis in the northwest State of Paraná, Brazil and establish their antimicrobial susceptibility profiles. A total of 507 foremilk samples were collected in 13 municipalities. Bacteria were identified and their profile of antimicrobial susceptibility were tested. The distribution of positive samples was not homogeneous among the cities. Streptococci were the most frequently genus observed (61%), followed by staphylococci (28%) and other genera (11%). Among streptococci and staphylococci, Streptococcus uberis and Staphylococcus aureus were the most frequently identified species, respectively. Overall, 40% of the isolates showed resistance to at least one of the antibiotics used in this study. A high proportion of cefoperazone resistant Staphylococcus spp. and bacitracin resistant Streptococcus were observed. The isolated microorganisms showed little resistance to enrofloxaxin. The results obtained show the importance of isolating the microorganism causing mastitis and testing its resistance to antibiotics before performing the treatment of the disease.
Topics: Female; Animals; Cattle; Milk; Brazil; Mastitis, Bovine; Methicillin-Resistant Staphylococcus aureus; Anti-Bacterial Agents; Staphylococcus; Cattle Diseases
PubMed: 38032282
DOI: 10.12834/VetIt.2606.16215.1 -
Frontiers in Veterinary Science 2023Intramammary infections (IMI) in animals reared for milk production can result in large economic losses and distress to the animals. is an important causative agent of...
Intramammary infections (IMI) in animals reared for milk production can result in large economic losses and distress to the animals. is an important causative agent of IMI in dairy cows, but its prevalence in water buffaloes has not been determined. Therefore, the current study was conducted to investigate the prevalence of subclinical mastitis in water buffaloes and the antimicrobial susceptibility, virulence genes and biofilm formation abilities of isolates recovered from water buffaloes in Guangdong, China. strains were isolated from milk samples of water buffaloes with subclinical mastitis, and twofold microdilution, PCR and crystal violet staining methods were used to determine antimicrobial susceptibility, distributions of virulence and antimicrobial resistance genes and biofilm formation ability, respectively. Our results indicated that 29.44% of water buffaloes were diagnosed with subclinical mastitis, and the most prevalent pathogens were (96.17%), coagulase-negative staphylococci (CoNS) (67.60%) and (28.57%). Most isolates showed resistance to bacitracin, doxycycline, penicillin, florfenicol, and tetracycline but were susceptible to ciprofloxacin, ceftizoxime, cefoquinoxime, and ofloxacin. Moreover, 63.72% of isolates were positive for and the prevalence of , , , , and ranged from 21.24 to 6.19%. All isolates harbored and genes, and the virulence genes (93.8%), (91.15%), (90.27%), (86.73%), and (83.19%), and , , , , , and showed a varied prevalence ranging from 3.5 to 65.49%. All isolates possessed the ability to form biofilms, and 30.09% of isolates showed strong biofilm formation abilities, while 19.47% of isolates were weak biofilm producers. Our results indicated that subclinical mastitis is prevalent in water buffaloes in Guangdong, China, and is prevalent in samples from water buffaloes with subclinical mastitis. Most isolates were susceptible to cephalosporins and fluoroquinolones; thus, ceftizoxime and cefoquinoxime can be used to treat subclinical mastitis in water buffaloes.
PubMed: 38026659
DOI: 10.3389/fvets.2023.1177302 -
Microbiology Spectrum Dec 2023Ceftriaxone-based antimicrobial therapies for gonorrhea are threatened by waning ceftriaxone susceptibility levels and the global dissemination of the high-level...
Ceftriaxone-based antimicrobial therapies for gonorrhea are threatened by waning ceftriaxone susceptibility levels and the global dissemination of the high-level ceftriaxone-resistant gonococcal FC428 clone. Combination therapy can be an effective strategy to restrain the development of ceftriaxone resistance, and for that purpose, it is important to find an alternative antimicrobial to replace azithromycin, which has recently been removed in some countries from the recommended ceftriaxone plus azithromycin dual-antimicrobial therapy. Ideally, the second antimicrobial should display synergistic activity with ceftriaxone. We hypothesized that bacitracin might display synergistic activity with ceftriaxone because of their distinct mechanisms targeting bacterial cell wall synthesis. In this study, we showed that bacitracin indeed displays synergistic activity with ceftriaxone against . Importantly, strains associated with the FC428 clone appeared to be particularly susceptible to the bacitracin plus ceftriaxone combination, which might therefore be an interesting dual therapy for further testing.
Topics: Humans; Ceftriaxone; Gonorrhea; Anti-Bacterial Agents; Azithromycin; Bacitracin; Microbial Sensitivity Tests; Neisseria gonorrhoeae; Drug Resistance, Bacterial
PubMed: 37982635
DOI: 10.1128/spectrum.02449-23 -
Frontiers in Microbiology 2023The operon encodes proteins responsible for the esterification of positively charged D-alanine on the wall teichoic acids and lipoteichoic acids of Gram-positive...
INTRODUCTION
The operon encodes proteins responsible for the esterification of positively charged D-alanine on the wall teichoic acids and lipoteichoic acids of Gram-positive bacteria. This structural modification of the bacterial anionic surface in several species has been described to alter the physicochemical properties of the cell-wall. In addition, it has been linked to reduced sensibilities to cationic antimicrobial peptides and antibiotics.
METHODS
We studied the D-alanylation of polysaccharides with a complete deletion of the operon in the 630 strain. To look for D-alanylation location, surface polysaccharides were purified and analyzed by NMR. Properties of the mutant and the parental strains, were determined for bacterial surface's hydrophobicity, motility, adhesion, antibiotic resistance.
RESULTS
We first confirmed the role of the operon in D-alanylation. Then, we established the exclusive esterification of D-alanine on lipoteichoic acid. Our data also suggest that D-alanylation modifies the cell-wall's properties, affecting the bacterial surface's hydrophobicity, motility, adhesion to biotic and abiotic surfaces,and biofilm formation. In addition, our mutant exhibitedincreased sensibilities to antibiotics linked to the membrane, especially bacitracin. A specific inhibitor DLT-1 of DltA reduces the D-alanylation rate in but the inhibition was not sufficient to decrease the antibiotic resistance against bacitracin and vancomycin.
CONCLUSION
Our results suggest the D-alanylation of as an interesting target to tackle infections.
PubMed: 37965542
DOI: 10.3389/fmicb.2023.1267662 -
Kansas Journal of Medicine 2023Intra-articular antibiotics have been proposed as a treatment for septic arthritis to allow for high local concentrations without subjecting a patient to the... (Review)
Review
INTRODUCTION
Intra-articular antibiotics have been proposed as a treatment for septic arthritis to allow for high local concentrations without subjecting a patient to the toxicity/side effects of systemic therapy. However, there is concern for chondrotoxicity with intra-articular use of these solutions in high concentrations. The purpose of this systematic review was to evaluate the intra-articular use of antibiotics and antiseptic solutions, and to determine their association with chondrolysis following or administration.
METHODS
A systematic review was conducted following PRISMA guidelines through PubMed, Clinical Key, OVID, and Google Scholar. Studies in English were included if they evaluated for chondrotoxicity following antibiotic exposure.
RESULTS
The initial search resulted in 228 studies, with 36 studies meeting criteria. These 36 studies included manuscripts that studied 24 different agents. Overall, 7 of the 24 (29%) agents were non-chondrotoxic: minocycline, tetracycline, chloramphenicol, teicoplanin, pefloxacin, linezolid, polymyxin-bacitracin. Eight (33%) agents had inconsistent results: doxycycline, ceftriaxone, gentamicin, vancomycin, ciprofloxacin, ofloxacin, chlorhexidine, and povidone iodine. Chondrotoxicity was evident with 9 (38%) agents, all of which were also dose-dependent chondrotoxic based on reported estimated half maximal inhibitory concentrations (est. IC50): amikacin (est. IC50 = 0.31-2.74 mg/mL), neomycin (0.82), cefazolin (1.67-3.95), ceftazidime (3.16-3.59), ampicillin-sulbactam (8.64 - >25), penicillin (11.61), amoxicillin (14.01), imipenem (>25), and tobramycin (>25). Additionally, chondroprotective effects of doxycycline and minocycline were reported.
CONCLUSIONS
This systematic review identified agents that may be used in the treatment of septic arthritis. Nine agents should be avoided due to their dose-dependent chondrotoxic effects. Further studies are needed to clarify the safety of these medications for human intra-articular use.
PubMed: 37954883
DOI: 10.17161/kjm.vol16.20357 -
Translational Animal Science 2023Tightening global regulations on the use of subclinical dietary antibiotics to enhance broiler growth are in response to increasing concern about the risk of resistance...
Tightening global regulations on the use of subclinical dietary antibiotics to enhance broiler growth are in response to increasing concern about the risk of resistance and their residues in animal products. The study evaluated the potential of apple cider vinegar (ACV) and garlic extract (GAE) as safer, phytogenic alternatives. A batch of 390 mixed-sex Ross 308-d-old broiler chicks was received into an open, deep litter house, and feather sexed in the second week into 30 experimental units of 13 birds per 2.03 m pen. From days 1 to 22, all chicks were on a 200 g/kg crude protein, coccidiostat-treated commercial starter diet. During the grower (16 to 28 days) and finisher (29 to 42 days) phases, chick pens were assigned treatments in a 2 (sex) × 5 (additives) factorial experiment replicated three times. The GAE was a pure extract, while ACV was produced by fermenting 1,000 g fresh apple and 80 g supplementary brown cane sugar in 1.3 liters of water for 4 wk. The five treatments comprised antibiotic (15% granular zinc bacitracin and 12% valinomycin sodium, each at 500 g/tonne) grower (190 g/kg crude protein, 13.0 MJ ME/kg) and finisher (165 g/kg crude protein, 13.2 MJ ME/kg) commercial diets with untreated drinking water as positive controls (PC), antibiotic-free duplicates of the PC diets with untreated drinking water as the negative controls (NC), with 3 mL/L filtered ACV in drinking water (T1), 2 mL/L filtered GAE-treated drinking water (T2), or mixed (3 mL/L ACV + 2mL/L GAE) additive drinking water (T3). Males had higher ( < 0.05) feed intake than females in both growth phases. Birds on the PC gained more ( < 0.05) weight than others. Birds on the PC consumed more feed ( < 0.05) during the finisher phase than T1, T2, and the NC. Birds on the PC had a lower ( < 0.05) grower-phase feed convesion (feed:gain) ratio (FCR) than others, and lower ( < 0.05) FCR during the finisher phase than birds on T1 and T3. Birds on the PC had higher ( < 0.05) percent spleen weight than birds on T1, with smaller proventriculi ( < 0.05) than on NC, T1, T2, and T3, and smaller gizzard weight than birds on the T2 and T3. Birds on the NC exhibited less dressing percentage ( < 0.05) than all other treatments. Meat pH was higher ( < 0.05) in males. In conclusion, in contrast to dietary antibiotics, except for improved dressing percentage, the ACV and GAE did not express phytogenic benefit at the experimental dosage.
PubMed: 37901203
DOI: 10.1093/tas/txad109