Bacterial Susceptibility to Ceria Nanoparticles: The Critical Role of Surrounding Molecules.

Investigating the ternary relationship among nanoparticles (NPs), their immediate molecular environment, and test organisms rather than the direct interaction between pristine NPs and test organisms has been thrust into the mainstream of nanotoxicological research. Diverging from previous work that predominantly centered on surrounding molecules affecting the toxicity of NPs by modulating their nanoproperties, this study has unveiled a novel dimension: surrounding molecules altering bacterial susceptibility to NPs, consequently impacting the outcomes of nanobio interaction. The study found that adding nitrate as the surrounding molecules could alter bacterial respiratory pathways, resulting in an enhanced reduction of ceria NPs (nanoceria) on the bacterial surfaces. This, in turn, increased the ion-specific toxicity originating from the release of Ce3+ ions at the nanobio interface. Further transcriptome analysis revealed more mechanistic details underlying the nitrate-induced changes in the bacterial energy metabolism and subsequent toxicity patterns. These findings offer a new perspective for the deconstruction of nanobio interactions and contribute to a more comprehensive understanding of NPs' environmental fate and ecotoxicity.

Antimicrobials administration, treatment outcome and bacterial susceptibility in canine pyometra cases subjected to ovariohysterectomy.

Pyometra is a bacterial uterine infection that frequently affects intact older bitches. The treatment of choice is ovariohysterectomy, often associated with perioperative antimicrobial therapy. The aim of this retrospective investigation was to evaluate the antibiotic choice at different administration times (pre-surgery, at surgery/during hospitalization, and post-surgery) against complications and outcomes, considering the susceptibility profile of bacteria. The medical records of 51 bitches referred to the Veterinary Teaching Hospital of the University of Turin (January 2021-November 2023) and subjected to ovariohysterectomy and bacteriological examination (bacterial culture and susceptibility tests) of the uterine exudate, were analysed. All animals had a positive outcome without surgical site infections, with a longer hospitalization time in case of peritonitis or sepsis; antimicrobials were administered for an average of 7 days. Comparing the susceptibility of the isolated bacteria towards the antimicrobials administered before, during and after surgery, complete efficacy was observed in 42 %, 46 % and 50 % of cases, respectively. In addition, 5/16 peritonitis cases were treated with an in vitro ineffective antimicrobial, and 30 % of the bitches never received a fully effective antibiotic, according to susceptibility tests using the minimum inhibitory concentration method (MIC). Cephazolin resulted the best option for Escherichia coli, the most frequently isolated bacterium. Our study confirms that pyometra has a good prognosis following ovariohysterectomy and antibiotic administration. Monitoring the clinical evolution without changing the antibiotic according to bacterial susceptibility could represent the right choice in uncomplicated cases. Evaluation of outcomes without postoperative antibacterial treatment or with a shorter course would be another topic worth investigating, with the aim to judiciously reduce the use of antibiotics.

Highly efficient hydrophobic nanocomposite in the decontamination of micropollutants and bacteria from aqueous wastes: A sustainable approach.

Micro-pollutants (specifically antibiotics and personal care products) and potential bacterial contamination pose a severe threat to human health and marine life. The study derives indigenous novel fibrous hydrophobic nanocomposite, efficient in decontaminating the micro-pollutants (tetracycline (TC) and bisphenol A (BPA)) and potential pathogens (S. pyogenes and E. coli) from aqueous wastes. A facile method synthesizes the fibrous attapulgite (ATP)- poly(4-vinylpyridine-co-styrene) (PVP) framework decorated in situ with the Ag0 nanoparticles (ATP@PVP/Ag0). A greener method using the Artocarpus heterophyllus leaf extract derives the Ag0(NPs). Various analytical methods extensively characterize the materials. A comprehensive study that includes pH, concentration, background electrolytes, and ionic strength reveals the sorptive removal insights of TC and BPA utilizing the ATP@PVP solid. The elimination of tetracycline (TC) and bisphenol A (BPA) agrees well with the pseudo-second-order kinetics. The pH 3.07 and 6.06 favor removing TC and BPA with the capacity of 10.86 mg/g and 17.36 mg/g at 25 °C. The hydrogen bonding and hydrophobic interactions predominate the sorption mechanism, and the material shows remarkable stability and reusability in repeated sorption/desorption operations. Similarly, the natural water implications and flow-bed system show fair applicability of solid in decontaminating the TC and BPA in an aqueous medium. Further, the material ATP@PVP/Ag0 exhibits very high inhibition of potential pathogens S. pyogenes and E. coli and optimizes the solid dose and solution pH.

A Comparative Analysis of Bacterial Adhesion on Different Long-Term Provisional Fixed Prostheses Fabricated by CAD/CAM Milling, 3D Printing, and Heat Cure Technique: An In Vivo Study.

Objectives: This study compares the bacterial susceptibility to three different provisional restorations manufactured with different laboratory techniques, i.e., heat cure, CAD/CAM, and 3D printing. Materials and Methods: Totally, 45 health patients with age group of 30-60 years undergoing complete veneer crown treatment were selected for the study and divided into three groups with 15 samples in each as Group I: the crowns were made from polymethyl methacrylate polymer fabricated by the conventional heat cure method, Group 2: the crowns were made from polymethyl methacrylate fabricated by subtractive manufacturing CAD/CAM method, and Group 3: the crowns were made from oligomers fabricated by additive manufacturing 3D printing. The samples were examined for bacterial adherence at scanning electron microscope. The colony-forming units (CFUs) were calculated, and statistically analyzed. Results: It has been determined that the digitally fabricated provisional restorations prove to be superior in terms of surface topography than to the conventionally fabricated provisional restorations. Conclusion: The study concludes that 3D-printed provisional restorations are more precise with reduced bacterial susceptibility than milled ones.

Comparison of In Vitro Bacterial Susceptibility to Common and Novel Equine Wound Care Dressings.

Antimicrobial resistance is becoming a problem of concern in the veterinary field, necessitating the use of effective topical treatments to aid the healing of wounds. Honey has been used for thousands of years for its medicinal properties, but in recent years medical-grade Manuka honey has been used to treat infected wounds. The goal of this study was to determine the relative susceptibility of four common equine wound pathogens to ten different types of antimicrobial agents based on the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The pathogens studied include ATCC lab-acclimated Pseudomonas aeruginosa, Escherichia coli, and methicillin-resistant Staphylococcus aureus and one from an equine sample submitted to the Colorado State Veterinary Diagnostic Laboratory (Streptococcus equi ssp. zooepidemicus (Streptococcus zooepidemicus)). An additional goal of the study was to describe the comparison of bactericidal activity of medical-grade Manuka honey, local honey, and commercial, food-grade honey to other commonly used wound dressings (20% hypertonic saline, silver sulfadiazine cream, PHMB gauze, and PHMB foam). The objective is to provide veterinary practitioners with comparative data on the use of a variety of antimicrobial dressings for inhibiting the growth of common wound bacteria. MIC and MBC for Manuka, store, and local honeys were comparable to those of sterile gauze, sugar, and hypertonic saline. Across bacterial species, local honey proved to have more bactericidal activity when compared to Manuka honey and commercial, food-grade honey. The MIC and MBC for PHMB gauze and foam was consistently at a higher dilution compared to the other antimicrobials. The majority of antimicrobials exhibited stronger inhibitory and bactericidal activity against a Streptococcus zooepidemicus isolate obtained from a wound compared to other bacteria that were ATCC lab-acclimated. Additional research for in vivo applications needs to be done to see whether differences exist in effective wound management.

Iron supplementation in the diets of hybrid catfish (Ictalurus punctatus × I. furcatus) juveniles affected haematocrit levels and potentially decreased disease resistance to Edwardsiella ictaluri.

To prevent catfish idiopathic anaemia, diets fortified with iron have been adopted as a regular practice on commercial catfish farms to promote erythropoiesis. However, the effects of prolonged exposure of excess dietary iron on production performance and disease resistance for hybrid catfish (Ictalurus punctatus × I. furcatus) remains unknown. Four experimental diets were supplemented with ferrous monosulphate to provide 0, 500, 1000, and 1500 mg of iron per kg of diet. Groups of 16 hybrid catfish juveniles (~22.4 g) were stocked in each of 20, 110-L aquaria (n = 5), and experimental diets were offered to the fish to apparent satiation for 12 weeks. At the end of the study, production performance, survival, condition indices, as well as protein and iron retention were unaffected by the dietary treatments. Blood haematocrit and the iron concentration in the whole-body presented a linear increase with the increasing the dietary iron. The remaining fish from the feeding trial was challenged with Edwardsiella ictaluri. Mortality was mainly observed for the dietary groups treated with iron supplemented diets. The results for this study suggest that iron supplementation beyond the required levels does affect the blood production, and it may increase their susceptibility to E. ictaluri infection.

Erlotinib-containing benzenesulfonamides as anti-Helicobacter pylori agents through carbonic anhydrase inhibition.

Aim: Development of dual-acting antibacterial agents containing Erlotinib, a recognized EGFR inhibitor used as an anticancer agent, with differently spaced benzenesulfonamide moieties known to bind and inhibit Helicobacter pylori carbonic anhydrase (HpCA) or the antiviral Zidovudine. Methods & materials: Through rational design, ten derivatives were obtained via a straightforward synthesis including a click chemistry reaction. Inhibitory activity against a panel of pathogenic carbonic anhydrases and antibacterial susceptibility of H. pylori ATCC 43504 were assessed. Docking studies on α-carbonic anhydrase enzymes and EGFR were conducted to gain insight into the binding mode of these compounds. Results & conclusion: Some compounds proved to be strong inhibitors of HpCA and showed good anti-H. pylori activity. Computational studies on the targeted enzymes shed light on the interaction hotspots.

Functional characterization of Labeo rohita muscle cell line for in vitro research.

BACKGROUND: Labeo rohita represents the most dominant fish species in Indian aquaculture and the fish cell lines have been used as an excellent in vitro platform for performing various biological research. METHODS AND RESULTS: The LRM cell culture developed from the muscle tissue of L. rohita was used to study the in vitro applications. The developed muscle cells were maintained in a Leibovitz's-15 (L-15) supplemented with 10% FBS (Fetal Bovine Serum) and 10 ng/ml bFGF at 28 oC temperature. The LRM cells showed fibroblastic-like morphology and was authenticated by sequencing mitochondrial gene 16S rRNA. The expression of myogenic regulatory factors (MRFs) was studied in different stages of LRM cells; however, the expression patterns varied at different passages. The MEF2A, Mrf-4, and Myogenin expressions were higher in passage 25, while the expression of MyoD was maximum in passage 15, and the expression of Myf-5 was highest in passage 1. The transfection efficiency of LRM cells revealed 14 % of the GFP expression with a pmaxGFP vector DNA. The LRM cells were susceptible to the extracellular products prepared from Aeromonas hydrophilla and Edwardsiella tarda. The acute cytotoxicity of six heavy metals (Hg, Cd, Zn, Cu, Pb, Ni) was assessed in LRM cells by a dose-dependent manner in comparison to IC50 values obtained from MTT and NR assays. A revival rate of 70-75% was achieved when the LRM cells were cryopreserved at - 196 °C using liquid nitrogen. CONCLUSION: The developed muscle cells serve as an functional in vitro tool for toxicological and biotechnological studies.

Revealing the Second and the Third Causes of AgNPs Property to Restore the Bacterial Susceptibility to Antibiotics.

The increase in bacterial resistance to antibiotics is a global problem for public health. In our previous works, it was shown that the application of AgNPs in cow mastitis treatment increased S. aureus and S. dysgalactiae susceptibility to 31 antibiotics due to a decrease in the bacterial efflux effect. The aim of the present work was to shed light on whether the change in adhesive and anti-lysozyme activities caused by AgNPs also contribute to the restoration of bacterial susceptibility to antibiotics. In vivo sampling was performed before and after cow mastitis treatments with antibiotics or AgNPs. The isolates were identified, and the adhesive and anti-lysozyme activities were assessed. These data were compared with the results obtained for in vitro pre-treatment of reference bacteria with AgNPs or antibiotics. The present study revealed that bacterial treatments in vitro and in vivo with AgNPs: (1) decrease the bacterial ability to adhere to cells to start an infection and (2) decrease bacterial anti-lysozyme activity, thereby enhancing the activity of lysozyme, a natural "antibiotic" present in living organisms. The obtained data contribute to the perspective of the future application of AgNPs for recovering the activity of antibiotics rapidly disappearing from the market.

Neutrophil defect and lung pathogen selection in cystic fibrosis.

Cystic fibrosis is a life-threatening genetic disorder caused by mutations in the CFTR chloride channel. Clinically, over 90% of patients with cystic fibrosis succumb to pulmonary complications precipitated by chronic bacterial infections, predominantly by Pseudomonas aeruginosa and Staphylococcus aureus. Despite the well-characterized gene defect and clearly defined clinical sequelae of cystic fibrosis, the critical link between the chloride channel defect and the host defense failure against these specific pathogens has not been established. Previous research from us and others has uncovered that neutrophils from patients with cystic fibrosis are defective in phagosomal production of hypochlorous acid, a potent microbicidal oxidant. Here we report our studies to investigate if this defect in hypochlorous acid production provides P. aeruginosa and S. aureus with a selective advantage in cystic fibrosis lungs. A polymicrobial mixture of cystic fibrosis pathogens (P. aeruginosa and S. aureus) and non-cystic fibrosis pathogens (Streptococcus pneumoniae, Klebsiella pneumoniae, and Escherichia coli) was exposed to varied concentrations of hypochlorous acid. The cystic fibrosis pathogens withstood higher concentrations of hypochlorous acid than did the non-cystic fibrosis pathogens. Neutrophils derived from F508del-CFTR HL-60 cells killed P. aeruginosa less efficiently than did the wild-type counterparts in the polymicrobial setting. After intratracheal challenge in wild-type and cystic fibrosis mice, the cystic fibrosis pathogens outcompeted the non-cystic fibrosis pathogens and exhibited greater survival in the cystic fibrosis lungs. Taken together, these data indicate that reduced hypochlorous acid production due to the absence of CFTR function creates an environment in cystic fibrosis neutrophils that provides a survival advantage to specific microbes-namely, S. aureus and P. aeruginosa-in the cystic fibrosis lungs.

Update on Therapeutic Drug Monitoring of Beta-Lactam Antibiotics in Critically Ill Patients-A Narrative Review.

Beta-lactam antibiotics remain one of the most preferred groups of antibiotics in critical care due to their excellent safety profiles and their activity against a wide spectrum of pathogens. The cornerstone of appropriate therapy with beta-lactams is to achieve an adequate plasmatic concentration of a given antibiotic, which is derived primarily from the minimum inhibitory concentration (MIC) of the specific pathogen. In a critically ill patient, the plasmatic levels of drugs could be affected by many significant changes in the patient's physiology, such as hypoalbuminemia, endothelial dysfunction with the leakage of intravascular fluid into interstitial space and acute kidney injury. Predicting antibiotic concentration from models based on non-critically ill populations may be misleading. Therapeutic drug monitoring (TDM) has been shown to be effective in achieving adequate concentrations of many drugs, including beta-lactam antibiotics. Reliable methods, such as high-performance liquid chromatography, provide the accurate testing of a wide range of beta-lactam antibiotics. Long turnaround times remain the main drawback limiting their widespread use, although progress has been made recently in the implementation of different novel methods of antibiotic testing. However, whether the TDM approach can effectively improve clinically relevant patient outcomes must be proved in future clinical trials.

Optimizing Helicobacter pylori Treatment: An Updated Review of Empirical and Susceptibility Test-Based Treatments.

As the rate of discovery of drug-resistant Helicobacter pylori cases increases worldwide, the relevant societies have updated their guidelines for primary eradication regimens. A promising strategy against drug-resistant H. pylori is tailored therapy based on the results of an antibiotic susceptibility test; however, it is difficult to apply this strategy to all cases. Although culture-based antibiotic susceptibility tests can assess resistance to any antimicrobial agent, their greatest disadvantage is the time required to draw a conclusion. In contrast, molecular-based methods, such as polymerase chain reaction, can rapidly determine the presence of resistance, although a single test can only test for one type of antimicrobial agent. Additionally, the limited availability of facilities for molecular-based methods has hindered their widespread use. Therefore, low-cost, minimally invasive, simple, and effective primary regimens are needed. Several studies have compared the efficacy of the latest primary eradication regimens against that of tailored therapies, and their results have shaped guidelines. This article reviews the latest research on empirical and tailored treatments for H. pylori infections. Evidence for the superiority of tailored therapy over empirical therapy is still limited and varies by region and treatment regimen. A network meta-analysis comparing different empirical treatment regimens showed that vonoprazan triple therapy provides a superior eradication effect. Recently, favorable results towards vonoprazan dual therapy have been reported, as it reached eradication levels similar to those of vonoprazan triple therapy. Both vonoprazan dual therapy and tailored therapy based on antibiotic susceptibility tests could contribute to future treatment strategies.

Fast identification and susceptibility determination of E. coli isolated directly from patients' urine using infrared-spectroscopy and machine learning.

For effective treatment, it is crucial to identify the infecting bacterium at the species level and to determine its antimicrobial susceptibility. This is especially true now, when numerous bacteria have developed multidrug resistance to most commonly used antibiotics. Currently used methods need âˆ¼ 48 h to identify a bacterium and determine its susceptibility to specific antibiotics. This study reports the potential of using infrared spectroscopy with machine learning algorithms to identify E. coli isolated directly from patients' urine while simultaneously determining its susceptibility to antibiotics within âˆ¼ 40 min after receiving the patient's urine sample. For this goal, 1,765 E. coli isolates purified directly from urine samples were collected from patients with urinary tract infections (UTIs). After collection, the samples were tested by infrared microscopy and analyzed by machine learning. We achieved success rates of âˆ¼ 96% in isolate level identification and âˆ¼ 84% in susceptibility determination.

Antibiogram at a Rural Hospital Against the Background of COVID-19: A Five-Year Retrospective Review.

Background and objective The role of the antibiogram in reducing hospital length of stay (LOS), mortality rate, health care costs, and, by extension, patients' social, physical, and emotional wellness has a significant impact on the medical community. Hospitals in large cities serve a dynamic population of diverse ethnic groups. Many scholarly works and publications have shown that the antimicrobial pattern in rural settings has significant variability annually. Over the last two years, the spread of coronavirus disease 2019 (COVID-19) has brought about many unknowns in the sphere of healthcare. The pattern of pathology accompanying COVID-19 has affected hospital policies and direct patient management, leading to a paradigm shift in approaches, policies, and resource utilization. The years 2019 to 2021 were marked by many admissions due to COVID-19, and the effects of COVID-19 are still being studied. In light of this, this study examined the changes in sensitivity patterns, new trends, and nature of bacteria isolates, antimicrobial rates, and susceptibility based on a rural hospital's annual antibiogram pertaining to its central departments: the intensive care unit (ICU), patient care unit (PCU), the outpatient unit, and emergency department (ED). Methods This five-year retrospective antibiogram review compared antibiogram patterns two years before the first case of COVID-19 was reported in the hospital and those two years after the initial outbreak. Results The organism comparative susceptibility tests for Escherichia coli (E. coli) were not significant except for increased susceptibility toward nitrofurantoin (p=0.003); Klebsiella pneumoniae (K. pneumoniae) was also not significant except for the increased susceptibility to ciprofloxacin (p=0.003). Pseudomonas aeruginosa (P. aeruginosa) had no changes in susceptibility patterns, while Proteus mirabilis (P. mirabilis) had increased susceptibility to imipenem (p=0.05), aztreonam (p=0.00), and meropenem (p=0.004), with reduced susceptibility to gentamicin (97.47% vs. 88.24%, p=0.006). There was a whopping decrease in the sensitivity of methicillin-resistant Staphylococcus aureus (MRSA) to clindamycin (75.93% vs. 50.7%, p=0.000), linezolid (99.54% vs. 88.73, p=0.004), trimethoprim/sulfamethoxazole (92.59% vs. 74.65%, p=0.001), and vancomycin (99.54% vs. 88.73%, p=0.004). Staphylococcus aureus (S. aureus) had no significant variation except an increase in susceptibility to nitrofurantoin (p=0.023), and perhaps ironically, Streptococcus pneumoniae (S. pneumoniae) had no significant changes in susceptibility pattern. Conclusion Our data demonstrate that the susceptibility of different drugs against different bacterial pathogens varied. However, some antibiotic drugs were found to have high susceptibility against different isolated organisms, and these drugs include amikacin, levofloxacin, vancomycin, cefotaxime, nitrofurantoin, and ceftriaxone. Some organisms showed a significantly declined antibiotic susceptibility, while others showed a significant improvement. The role of COVID-19 regarding these changes is unknown. COVID-19 may not be the cause of the observed differences. We believe that further research on antibiotic legislation and prescribing trends is required. Other non-significant study findings may be attributed to the limited data available to us.

External Ear Canal Evaluation in Dogs with Chronic Suppurative Otitis Externa: Comparison of Direct Cytology, Bacterial Culture and 16S Amplicon Profiling.

A discrepancy between cytology and bacterial culture methods is sometimes observed in canine otitis externa. The objective of this study was to compare results from cytology, bacterial culture and 16S amplicon profiling. Twenty samples from 16 dogs with chronic suppurative otitis externa were collected. A direct cytological evaluation was carried out during the consultations. Aerobic bacterial culture and susceptibility were performed by an external laboratory used in routine practice. For 16S amplicon profiling, DNA was extracted and the hypervariable segment V1−V3 of the 16S rDNA was amplified and then sequenced with a MiSeq Illumina sequence carried out by the Mothur software using the SILVA database. A good correlation between cytology and bacterial culture was observed in 60% of the samples. Some bacterial species revealed by bacterial culture were present with low relative abundance (<10%) in 16S amplicon profiling. Some bacterial species revealed by the 16S amplicon profiling analysis were not identified with culture; most of the time, the offending species was a Corynebacterium. To conclude, a careful interpretation of the results of bacterial culture should be made and always be in agreement with the cytology. The 16S amplicon profiling method appears to be a more sensitive method for detecting strains present in suppurative otitis but does not provide information on bacterial susceptibility.

An established kidney cell line from humpback grouper (Cromileptes altivelis) and its susceptibility to bacteria and heavy metals.

Humpback grouper (Cromileptes altivelis), one kind of commercial fish with considerable economic value, has been recognized as a promising candidate for mariculture. In the wake of the development of aquaculture industry, the breeding density of C. altivelis has increased gradually, which gave rise to the occurrence of various pathogenic diseases. In our research, we established a new kidney cell line (designated as CAK) from humpback grouper and evaluated its susceptibility to bacteria and heavy metals. The results of our study showed that the optimal growth temperature was 26 °C, and optimal medium was L-15 supplemented with 20% fetal bovine serum (FBS). The sequencing of 18S rRNA gene indicated that CAK cell line was derived from C. altivelis. Chromosome analysis showed that the number of chromosome in CAK was 48. After being transfected of pEGFP-N3 plasmid, high transfection efficiency of CAK was observed, suggesting the potential to be used for the study of foreign functional genes. Moreover, the bacterial susceptibility results revealed that CAK cells were sensitive to Vibrio harveyi and Edwardsiella tarda, especially V. harveyi. Meanwhile, three heavy metals (Hg, Cu, and Cd) had toxic effects on the CAK cells with a dose-dependent manner. To sum up, the CAK cell line might be an ideal tool in vitro for analyzing the function of exogenous genes, bacterial susceptibility, and toxicity assay of heavy metals.

Infra-red spectroscopy combined with machine learning algorithms enables early determination of Pseudomonas aeruginosa's susceptibility to antibiotics.

Pseudomonas (P.) aeruginosa is a bacterium responsible for severe infections that have become a real concern in hospital environments. Nosocomial infections caused by P. aeruginosa are often hard to treat because of its intrinsic resistance and remarkable ability to acquire further resistance mechanisms to multiple groups of antimicrobial agents. Thus, rapid determination of the susceptibility of P. aeruginosa isolates to antibiotics is crucial for effective treatment. The current methods used for susceptibility determination are time-consuming; hence the importance of developing a new method. Fourier-transform infra-red (FTIR) spectroscopy is known as a rapid and sensitive diagnostic tool, with the ability to detect minor abnormal molecular changes including those associated with the development of antibiotic- resistant bacteria. The main goal of this study is to evaluate the potential of FTIR spectroscopy together with machine learning algorithms, to determine the susceptibility of P. aeruginosa to different antibiotics in a time span of ∼20 min after the first culture. For this goal, 590 isolates of P. aeruginosa, obtained from different infection sites of various patients, were measured by FTIR spectroscopy and analyzed by machine learning algorithms. We have successfully determined the susceptibility of P. aeruginosa to various antibiotics with an accuracy of 82-90%.

Establishment of a new fish cell line from the brain of humpback grouper (Cromileptes altivelis) and its application in toxicology and bacterial susceptibility.

Cromileptes altivelis, humpback grouper, belongs to the family Epinephelidae and is one popular farmed fish species because of its high economic value and ornamental value. However, more and more diseases outbreaks have been reported with C. altivelis aquaculture. Today, a new brain cell line of C. altivelis (named CAB) was established and characterized. Our results showed that CAB cells were suitable for growth at 26 °C in L-15 medium supplemented with 15% fetal bovine serum (FBS). The results of 18S rRNA gene sequencing confirmed that CAB cell line was derived from C. altivelis. Moreover, chromosomal aneuploidy was observed in CAB cells, and the modal chromosome number of CAB cells was 48 by chromosome analysis. In addition, CAB cells could transfect pEGFP-N3 plasmid with high transfection efficiency, indicating that CAB cell line has the potential to investigate the function of exogenous genes in vitro. Furthermore, the bacterial susceptibility results suggested that CAB cells were susceptive to Vibrio harveyi and Edwardsiella tarda. And, heavy metals (Hg, Cd, and Cu) were toxic to the CAB cells, and the toxic effect was dose-dependent. In summary, the CAB cell line could be a powerful tool in vitro to study functional genes and has the potential application in bacterial susceptibility and toxicology.

Risk and clinical impact of bacterial resistance/susceptibility to silver-based wound dressings: a systematic review.

OBJECTIVE: To perform a systematic review of the literature on bacterial resistance, tolerance and susceptibility of silver within the context of wound therapy using silver-based dressings. METHODS: A literature search was carried out using PubMed, Embase and Cochrane Library databases, the focus was whether results from microbiological experimental in vitro tests with reference strains and clinical wound isolates are reflected in clinical practice with regards to their 'resistance' profiles, comparable with those observed for antibiotics. The search results were allocated to six categories: resistance and resistance mechanism, in vitro tests with standard strains and wound isolates, prevalence and incidence, impact on clinical practice and impact on antibiotic therapy as well as reviews, expert opinions and consensus. RESULTS: Based on all findings of the literature, it cannot be confirmed that a related clinical resistance to silver-ions in silver-based dressings has clinical impact, although endogenous and exogenous genetic resistance patterns have been described and intensively investigated. A translation of these genetic resistance-expression structures to phenotypic appearances, similar to those known for antibiotics, has not been demonstrated for silver in the literature. CONCLUSION: It can be concluded that there is no definitive evidence available and further studies should be conducted.

In Vitro and Intracellular Activities of Omadacycline against Legionella pneumophila.

Omadacycline is an aminomethylcycline antibiotic with in vitro activity against pathogens causing community-acquired bacterial pneumonia (CABP). This study investigated the activity of omadacycline against Legionella pneumophila strains isolated between 1995 and 2014 from nosocomial or community-acquired respiratory infections. Omadacycline exhibited extracellular activity similar to comparator antibiotics; intracellular penetrance was found by day 3 of omadacycline exposure. These results support the utility of omadacycline as an effective antibiotic for the treatment of CABP caused by L. pneumophila.