ABSTRACT
Sepsis is a common disease with high morbidity and mortality among newborns in intensive care units world-wide. Gram-negative bacillary bacteria are the major source of infection in neonates. Gentamicin is the most widely used aminoglycoside antibiotic in empiric therapy against early-onset sepsis. However, therapy failure may result due to various factors. The purpose of this study was to identify predictors of gentamicin therapy failure in neonates with sepsis. This was a prospective cross-sectional study at the Neonatal Intensive Care Unit at Windhoek Central Hospital over a period of 5 months in 2019. Neonates received intravenous gentamicin 5 mg/kg/24 h in combination with either benzylpenicillin 100 000 IU/kg/12 h or ampicillin 50 mg/kg/8 h. Logistic regression modeling was performed to determine the predictors of treatment outcomes. 36% of the 50 neonates were classified as having gentamicin treatment failure. Increasing treatment duration by 1 day resulted in odds of treatment failure increasing from 1.0 to 2.41. Similarly, one unit increase in CRP increases odds of gentamicin treatment failure by 49%. The 1 kg increase in birthweight reduces the log odds of treatment failure by 6.848, resulting in 99.9% decrease in the odds of treatment failure. One unit increase in WBC reduces odds of gentamicin treatment failure by 27%. Estimates of significant predictors of treatment failure were precise, yielding odds ratios that were within 95% confidence interval. This study identified the following as predictors of gentamicin therapy failure in neonates: prolonged duration of treatment, elevated C-reactive protein, low birthweight, and low white blood cell count.
Subject(s)
Anti-Bacterial Agents , Gentamicins , Intensive Care Units, Neonatal , Treatment Failure , Humans , Gentamicins/therapeutic use , Gentamicins/administration & dosage , Infant, Newborn , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/administration & dosage , Cross-Sectional Studies , Prospective Studies , Female , Male , Intensive Care Units, Neonatal/statistics & numerical data , Neonatal Sepsis/drug therapy , C-Reactive Protein/analysis , Sepsis/drug therapy , Sepsis/mortality , Birth Weight , Ampicillin/therapeutic use , Ampicillin/administration & dosageABSTRACT
A smartphone-assisted portable dual-mode immunoassay was constructed based on curcumin nanoparticles (CNPs) and carbon dots (CDs) for gentamicin (GEN) detection. CNPs were labeled with goat anti-mouse IgG (Ab2) to create a conjugation that coupled dual signals to concentrations of GEN antigens. CNPs were introduced to pH 7.4 water and showed insignificant color and optical responses. When exposed to the high pH environment, the structure of CNPs changed and color and optical properties were restored. Because of the inner filter effect (IFE) between CNPs and CDs, the fluorescence of CNPs at 550 nm quenched the fluorescence of CDs at 450 nm. Colorimetry and ratiometric fluorescence (F550 nm/F450 nm) dual-mode immunoassay linearly correlated with GEN ranged from 10-4 to 100 µg/mL with a detection limit (LOD) of 8.98 × 10-5 µg/mL and 4.66 × 10-5 µg/mL, respectively. This work supplied a portable, sensitive, and specific platform to detect GEN.
Subject(s)
Carbon , Curcumin , Gentamicins , Limit of Detection , Nanoparticles , Quantum Dots , Smartphone , Curcumin/chemistry , Immunoassay/methods , Carbon/chemistry , Gentamicins/analysis , Gentamicins/immunology , Gentamicins/chemistry , Quantum Dots/chemistry , Nanoparticles/chemistry , Animals , MiceABSTRACT
Bacteria often evolve antibiotic resistance through mutagenesis. However, the processes causing the mutagenesis have not been fully resolved. Here, we find that a broad range of ribosome-targeting antibiotics cause mutations through an underexplored pathway. Focusing on the clinically important aminoglycoside gentamicin, we find that the translation inhibitor causes genome-wide premature stalling of RNA polymerase (RNAP) in a loci-dependent manner. Further analysis shows that the stalling is caused by the disruption of transcription-translation coupling. Anti-intuitively, the stalled RNAPs subsequently induce lesions to the DNA via transcription-coupled repair. While most of the bacteria are killed by genotoxicity, a small subpopulation acquires mutations via SOS-induced mutagenesis. Given that these processes are triggered shortly after antibiotic addition, resistance rapidly emerges in the population. Our work reveals a mechanism of action of ribosomal antibiotics, illustrates the importance of dissecting the complex interplay between multiple molecular processes in understanding antibiotic efficacy, and suggests new strategies for countering the development of resistance.
Subject(s)
Anti-Bacterial Agents , DNA-Directed RNA Polymerases , Drug Resistance, Bacterial , Genomic Instability , Gentamicins , Ribosomes , Anti-Bacterial Agents/pharmacology , DNA-Directed RNA Polymerases/metabolism , DNA-Directed RNA Polymerases/genetics , Ribosomes/metabolism , Ribosomes/drug effects , Gentamicins/pharmacology , Drug Resistance, Bacterial/genetics , Escherichia coli/genetics , Escherichia coli/drug effects , Escherichia coli/metabolism , Mutation , Mutagenesis , Transcription, Genetic/drug effects , Protein Biosynthesis/drug effectsABSTRACT
CONTEXT: Meningitis is associated with high mortality risk in young infants, yet the optimal treatment regimen is unclear. OBJECTIVES: To systematically evaluate the efficacy of antibiotic regimens to treat meningitis in young infants aged 0 to 59 days on critical clinical outcomes. DATA SOURCES: MEDLINE, Embase, CINAHL, WHO Global Index Medicus, and Cochrane Central Registry of Trials. STUDY SELECTION: We included randomized controlled trials (RCTs) of young infants with meningitis (population) comparing the efficacy of antibiotic regimens (interventions) with alternate regimens (control) on clinical outcomes. DATA EXTRACTION: We extracted data on study characteristics and assessed risk of bias in duplicate. Grading of Recommendations Assessment, Development, and Evaluation was used to assess certainty of evidence. RESULTS: Of 1088 studies screened, only 2 RCTs were identified. They included 168 infants from 5 countries and were conducted between 1976 and 2015. Neither study compared current World Health Organization-recommended regimens. One multisite trial from 4 countries compared intrathecal gentamicin plus systemic ampicillin/gentamicin to systemic ampicillin/gentamicin and found no difference in mortality (relative risk, 0.88; 95% confidence interval, 0.41-1.53; 1 trial, n = 98, very low certainty of evidence) or adverse events (no events in either trial arm). Another trial in India compared a 10-day versus 14-day course of antibiotics and found no difference in mortality (relative risk, 0.88; 95% confidence interval, 0.41-1.53; 1 trial, n = 98, very low certainty of evidence) or other outcomes. CONCLUSIONS: Trial data on the efficacy of antibiotic regimens in young infant meningitis are scarce. Rigorous RCTs are needed to inform recommendations for optimal antibiotic regimens for meningitis treatment in this vulnerable population, particularly within the context of changing epidemiology and increasing antimicrobial resistance.
Subject(s)
Anti-Bacterial Agents , Meningitis, Bacterial , Humans , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/administration & dosage , Infant , Infant, Newborn , Meningitis, Bacterial/drug therapy , Meningitis, Bacterial/mortality , Randomized Controlled Trials as Topic , Treatment Outcome , Gentamicins/therapeutic use , Gentamicins/administration & dosageABSTRACT
Gentamicin is an aminoglycoside antibiotic with a rapid bactericidal effect on the treatment of many infections. However, its use at high concentrations for more than 7 days causes nephrotoxic side effects. This study investigated the potential of Resatorvid and alpha lipoic acid (ALA) in mitigating gentamicin-induced nephrotoxicity in rats, considering biochemical, histopathological, and molecular parameters. This study randomly distributed 34 Wistar albino rats into four groups: healthy control (n = 6), Gentamicin (80 mg/kg, n = 7), Gentamicin + Sham (%10 hydroalcoholic solution, n = 7), Gentamicin + Resatorvid (5 mg/kg, n = 7), and Gentamicin + ALA (100 mg/kg, n = 7). Resatorvid treatment led to a statistically significant decrease in urinary IL-18, KIM-1, and NGAL levels, whereas ALA treatment significantly reduced KIM-1 levels compared to the gentamicin-only group. Both Resatorvid and ALA showed partial reductions in urine creatinine levels. Moreover, treatments with Resatorvid and ALA resulted in statistically significant decreases in NRF-2, CAS-3, and NR4A2 expressions. However, only Resatorvid demonstrated a statistically significant decrease in NF-B expression. These findings highlight the potential of Resatorvid in ameliorating gentamicin-induced nephrotoxicity, thereby expanding the therapeutic utility of gentamicin and enhancing its efficacy against infections.
Subject(s)
Anti-Bacterial Agents , Gentamicins , Rats, Wistar , Thioctic Acid , Gentamicins/toxicity , Gentamicins/adverse effects , Animals , Thioctic Acid/pharmacology , Thioctic Acid/therapeutic use , Rats , Anti-Bacterial Agents/adverse effects , Anti-Bacterial Agents/pharmacology , Male , Kidney/drug effects , Kidney/pathology , Kidney/metabolism , Creatinine/blood , Creatinine/urine , Kidney Diseases/chemically induced , Kidney Diseases/drug therapy , Kidney Diseases/pathology , Antioxidants/pharmacology , Antioxidants/therapeutic use , Cell Adhesion MoleculesABSTRACT
Titanium-based implants have long been studied and used for applications in bone tissue engineering, thanks to their outstanding mechanical properties and appropriate biocompatibility. However, many implants struggle with osseointegration and attachment and can be vulnerable to the development of infections. In this work, we have developed a composite coating via electrophoretic deposition, which is both bioactive and antibacterial. Mesoporous bioactive glass particles with gentamicin were electrophoretically deposited onto a titanium substrate. In order to validate the hypothesis that the quantity of particles in the coatings is sufficiently high and uniform in each deposition process, an easy-to-use image processing algorithm was designed to minimize human dependence and ensure reproducible results. The addition of loaded mesoporous particles did not affect the good adhesion of the coating to the substrate although roughness was clearly enhanced. After 7 days of immersion, the composite coatings were almost dissolved and released, but phosphate-related compounds started to nucleate at the surface. With a simple and low-cost technique like electrophoretic deposition, and optimized stir and suspension times, we were able to synthesize a hemocompatible coating that significantly improves the antibacterial activity when compared to the bare substrate for both Gram-positive and Gram-negative bacteria.
Subject(s)
Anti-Bacterial Agents , Chitosan , Electrophoresis , Gentamicins , Glass , Materials Testing , Nanoparticles , Particle Size , Surface Properties , Titanium , Gentamicins/pharmacology , Gentamicins/chemistry , Titanium/chemistry , Titanium/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Glass/chemistry , Nanoparticles/chemistry , Chitosan/chemistry , Chitosan/pharmacology , Porosity , Microbial Sensitivity Tests , Humans , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Prostheses and Implants , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacologyABSTRACT
Vertigo, an unexpected feeling of self-motion, is no longer characterized simply by symptom quality but by using triggers and timing. Evaluating vertigo by triggers and timing not only distinguishes serious central causes from benign peripheral causes, but also narrows the differential diagnosis by further classifying vertigo as spontaneous episodic vestibular syndrome, triggered episodic vestibular syndrome, or acute vestibular syndrome. A targeted physical examination can then be used to further delineate the cause within each of these three vestibular categories. Neuroimaging and vestibular testing are not routinely recommended. In the management of vertigo, vestibular hypofunction can be treated with vestibular rehabilitation, which can be self-administered or directed by a physical therapist. Pharmacotherapy sometimes is indicated for vertigo based on triggers, timing, and the specific condition, but it is not always beneficial and is used more often for symptom reduction than as a cure. Transtympanic corticosteroid or gentamicin injections are recommended for patients who do not benefit from nonablative therapy. Surgical ablative therapy is reserved for patients who have not benefited from less definitive therapy and have nonusable hearing.
Subject(s)
Vertigo , Humans , Vertigo/therapy , Vertigo/diagnosis , Vertigo/etiology , Diagnosis, Differential , Physical Examination/methods , Family Practice/methods , Gentamicins/therapeutic use , Anti-Bacterial Agents/therapeutic use , Vestibular Function Tests/methodsABSTRACT
BACKGROUND: The study aims to investigate the effect of combining silver nanoparticles (AGNPs) with different antibiotics on multi-drug resistant (MDR) and extensively drug resistant (XDR) isolates of Pseudomonas aeruginosa (P. aeruginosa) and to investigate the mechanism of action of AGNPs. METHODS: AGNPs were prepared by reduction of silver nitrate using trisodium citrate and were characterized by transmission electron microscope (TEM) in addition to an assessment of cytotoxicity. Clinical isolates of P. aeruginosa were collected, and antimicrobial susceptibility was conducted. Multiple Antibiotic Resistance (MAR) index was calculated, and bacteria were categorized as MDR or XDR. Minimum inhibitory concentration (MIC) of gentamicin, ciprofloxacin, ceftazidime, and AGNPs were determined. The mechanism of action of AGNPs was researched by evaluating their effect on biofilm formation, swarming motility, protease, gelatinase, and pyocyanin production. Real-time PCR was performed to investigate the effect on the expression of genes encoding various virulence factors. RESULTS: TEM revealed the spherical shape of AGNPs with an average particle size of 10.84 ± 4.64 nm. AGNPS were safe, as indicated by IC50 (42.5 µg /ml). The greatest incidence of resistance was shown against ciprofloxacin which accounted for 43% of the bacterial isolates. Heterogonous resistance patterns were shown in 63 isolates out of the tested 107. The MAR indices ranged from 0.077 to 0.84. Out of 63 P. aeruginosa isolates, 12 and 13 were MDR and XDR, respectively. The MIC values of AGNPs ranged from 2.65 to 21.25 µg /ml. Combination of AGNPs with antibiotics reduced their MIC by 5-9, 2-9, and 3-10Fold in the case of gentamicin, ceftazidime, and ciprofloxacin, respectively, with synergism being evident. AGNPs produced significant inhibition of biofilm formation and decreased swarming motility, protease, gelatinase and pyocyanin production. PCR confirmed the finding, as shown by decreased expression of genes encoding various virulence factors. CONCLUSION: AGNPs augment gentamicin, ceftazidime, and ciprofloxacin against MDR and XDR Pseudomonas isolates. The efficacy of AGNPs can be attributed to their effect on the virulence factors of P. aeruginosa. The combination of AGNPs with antibiotics is a promising strategy to attack resistant isolates of P. aeruginosa.
Subject(s)
Anti-Bacterial Agents , Biofilms , Drug Resistance, Multiple, Bacterial , Metal Nanoparticles , Microbial Sensitivity Tests , Pseudomonas Infections , Pseudomonas aeruginosa , Silver , Pseudomonas aeruginosa/drug effects , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/physiology , Biofilms/drug effects , Silver/pharmacology , Silver/chemistry , Drug Resistance, Multiple, Bacterial/drug effects , Metal Nanoparticles/chemistry , Anti-Bacterial Agents/pharmacology , Humans , Pseudomonas Infections/microbiology , Pseudomonas Infections/drug therapy , Ciprofloxacin/pharmacology , Virulence Factors/genetics , Gentamicins/pharmacology , Microscopy, Electron, Transmission , Ceftazidime/pharmacologyABSTRACT
PURPOSE: The aim of this study was to quantify the prophylactic effect of high-dose gentamicin and clindamycin antibiotic-loaded bone cement (ALBC) during revision total hip (rTHA) or knee (rTKA) arthroplasty for aseptic reasons. The hypothesis was that the raw surgical site infection (SSI) rate is lower when this particular cement is used in comparison with cement loaded with standard-dose gentamicin during rTHA or rTKA for aseptic reasons. METHODS: This retrospective study included 290 consecutive patients undergoing aseptic rTHA or rTKA. Two consecutive cohorts were defined: the first (control group) involved 145 patients where ALBC with gentamicin only was used; the second (study group) involved 145 patients where ALBC with high-dose gentamicin and clindamycin was used. The primary endpoint was the raw SSI rate after 24 months. RESULTS: The raw SSI rate was 8/145 (6%) in the control group and 13/145 (9%) in the study group (odds ratio 0.62, p = 0.26). There was a significant impact of the presence of any risk factor on the SSI rate (15/100 versus 6/169, odds ratio = 4.25, p = 0.002), but no significant impact of any individual risk factor. No complication or side effect related to ALBC was observed in either group. CONCLUSION: These results do not support the routine use of gentamicin and clindamycin ALBC for fixation of revision implants after rTHA and rTKA for aseptic reasons.
Subject(s)
Anti-Bacterial Agents , Arthroplasty, Replacement, Hip , Arthroplasty, Replacement, Knee , Bone Cements , Clindamycin , Gentamicins , Prosthesis-Related Infections , Reoperation , Surgical Wound Infection , Humans , Gentamicins/administration & dosage , Clindamycin/administration & dosage , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Hip/methods , Retrospective Studies , Male , Female , Arthroplasty, Replacement, Knee/adverse effects , Aged , Anti-Bacterial Agents/administration & dosage , Middle Aged , Surgical Wound Infection/prevention & control , Prosthesis-Related Infections/prevention & control , Prosthesis-Related Infections/etiology , Risk FactorsABSTRACT
PURPOSE: Listeria monocytogenes causes severe bacterial infections with the highest mortality rate among foodborne pathogens in Europe. Combination treatment with ampicillin and gentamicin is recommended for invasive manifestations. However, evidence to support this treatment approach remains limited due to a lack of randomised controlled trials. To explore this critical issue further, we conducted this retrospective, single-center study. METHODS: We identified all patients hospitalized with invasive listeriosis at the University Medical Center Hamburg-Eppendorf between 2009 and 2020 and analyzed the effect of gentamicin combination treatment versus monotherapy on 90-day mortality. RESULTS: In total, 36 patients with invasive listeriosis were included, of which 21 patients received gentamicin combination treatment and 15 received monotherapy. The mean age-adjusted Charlson Comorbidity Index (aaCCI) value was lower in the gentamicin combination treatment group (5.4 vs. 7.4). Neurolisteriosis was more common in the gentamicin group (81% vs. 20%). The 90-day mortality was with significantly lower in the gentamicin combination treatment group (10%) compared to the monotherapy group (60%). Multivariable cox regression analysis, adjusted for a propensity score computed based on neurolisteriosis, aaCCI and sex, revealed a significantly reduced hazard ratio of 0.07 (95% CI: 0.01-0.53, p = 0.01) for 90-day mortality for the gentamicin combination treatment. CONCLUSION: This retrospective study highlights the benefit of gentamicin combination treatment in reducing the 90-day mortality rate among patients with invasive listeriosis. The high prevalence of monotherapy in this study cohort raises concerns about the adequacy of antibiotic therapy in clinical practice.
Subject(s)
Anti-Bacterial Agents , Drug Therapy, Combination , Gentamicins , Listeriosis , Humans , Gentamicins/therapeutic use , Retrospective Studies , Male , Female , Aged , Anti-Bacterial Agents/therapeutic use , Listeriosis/drug therapy , Listeriosis/mortality , Middle Aged , Aged, 80 and over , Listeria monocytogenes/drug effectsABSTRACT
Carbapenem-resistant Klebsiella pneumoniae (CPKP) infections seriously threaten global public health. The main objective of this study was to assess the in-vitro synergistic activity of ceftazidime-avibactam (CZA) in combination with colistin (COL), amikacin (AK), gentamicin (GEN), and fosfomycin (FOS) against CPKP isolates. The secondary goal was to determine the antibiotic susceptibility performance of BD Phoenix. OXA-48 (49.1%) was the predominant carbapenemase, followed by KPC (29.1%). We used the broth microdilution (BMD) method to determine the minimum inhibitory concentrations (MICs) of CZA, COL, AK, and GEN. Meanwhile, the MICs of FOS were determined by the agar dilution (AD) method. To examine the antibacterial activity of CZA, we conducted a checkerboard assay (CBA) with COL, AK, GEN, and FOS against CRKP isolates. We randomly selected three strains and performed synergy testing via time-kill assay (TKA). CRKP isolates were 89.1% susceptible to CZA, 16.4% to COL, 21.8% to GEN, and 29.1% to AK using BMD, 47.3% to FOS by AD. The most synergistic effects were observed in the combination of CZA-COL (78.2%) and CZA-FOS (63.6%). Given the limited therapeutic options for treating severe CRKP infections, combining CZA with COL and FOS may enhance in-vitro activity against clinical CRKP isolates.
Subject(s)
Amikacin , Anti-Bacterial Agents , Azabicyclo Compounds , Ceftazidime , Colistin , Drug Combinations , Drug Synergism , Fosfomycin , Gentamicins , Klebsiella pneumoniae , Microbial Sensitivity Tests , Ceftazidime/pharmacology , Klebsiella pneumoniae/drug effects , Azabicyclo Compounds/pharmacology , Fosfomycin/pharmacology , Anti-Bacterial Agents/pharmacology , Amikacin/pharmacology , Gentamicins/pharmacology , Colistin/pharmacology , Humans , Carbapenem-Resistant Enterobacteriaceae/drug effects , Klebsiella Infections/drug therapy , Klebsiella Infections/microbiologyABSTRACT
Containing information molecules from their parent cells and inclining to fuse with targeted cells, bone marrow mesenchymal stromal cells-derived extracellular vesicles (MSCs- EV) are valuable in nanomedicine. BACKGROUND: The effects of aging on the paracrine mechanism and in the production and action of MSCs-EV and their cargos of miR-26a and siRNA-26a for the treatment of tubular renal cells under nephrotoxicity injury remain unelucidated. OBJECTIVE: The purpose of this study was to evaluate MSCs-EV of different ages and their ability to deliver the cargos of miR-26a and siRNA-26a to target renal tubular cells affected by nephrotoxicity injury. METHODS: In a model of gentamicin-induced nephrotoxicity, renal tubular cells treated with MSCs-EV expressing or not expressing microRNA-26a were analyzed. Western blotting was utilized to evaluate cell cycle markers, and MTT assay was utilized to evaluate auto-renovation capacity. RESULTS: Tubular cells under nephrotoxicity injury showed decreased proliferative capacity, but the treatment in the tubular renal cells under nephrotoxicity injury with MSCs-EV expressing microRNA-26a showed nephroprotective effects, regardless of EV age. While the treatment with EV-mediated siRNA-26a failed to preserve the nephroprotective effects equally, regardless of age. CONCLUSION: Mesenchymal stromal cell nanovesicles carry microRNA with nephroprotective proprieties regardless of aging.
Subject(s)
Cell Proliferation , Kidney Tubules , Mesenchymal Stem Cells , MicroRNAs , Mesenchymal Stem Cells/metabolism , MicroRNAs/metabolism , MicroRNAs/genetics , Animals , Kidney Tubules/pathology , Kidney Tubules/metabolism , Aging/metabolism , Aging/pathology , Aging/genetics , Gentamicins/toxicity , Gentamicins/adverse effects , Extracellular Vesicles/metabolism , Extracellular Vesicles/genetics , Age Factors , RNA, Small Interfering/metabolism , RNA, Small Interfering/genetics , Cell Line , Cells, Cultured , Paracrine Communication , Disease Models, Animal , HumansABSTRACT
Given the significant impact of biofilms on human health and material corrosion, research in this field urgently needs more accessible techniques to facilitate the testing of new control agents and general understanding of biofilm biology. Microtiter plates offer a convenient format for standardized evaluations, including high-throughput assays of alternative treatments and molecular modulators. This study introduces a novel Biofilm Analysis Software (BAS) for quantifying biofilms from microtiter plate images. We focused on early biofilm growth stages and compared BAS quantification to common techniques: direct turbidity measurement, intrinsic fluorescence detection linked to pyoverdine production, and standard crystal violet staining which enables image analysis and optical density measurement. We also assessed their sensitivity for detecting subtle growth effects caused by cyclic AMP and gentamicin. Our results show that BAS image analysis is at least as sensitive as the standard method of spectrophotometrically quantifying the crystal violet retained by biofilms. Furthermore, we demonstrated that bacteria adhered after short incubations (from 10 min to 4 h), isolated from planktonic populations by a simple rinse, can be monitored until their growth is detectable by intrinsic fluorescence, BAS analysis, or resolubilized crystal violet. These procedures are widely accessible for many laboratories, including those with limited resources, as they do not require a spectrophotometer or other specialized equipment.
Subject(s)
Biofilms , Image Processing, Computer-Assisted , Software , Biofilms/growth & development , Image Processing, Computer-Assisted/methods , Gentian Violet , Bacteria/growth & development , Bacterial Adhesion , Gentamicins/pharmacologyABSTRACT
To reveal the protective effect on the nephrotoxicity of Quercus salicina Blume(QS), a traditional medicine for the treatment of urolithiasis, the 50 % ethanol extract from the branches and leaves of QS was chemically studied by systematic solvent extraction and HPLC chromatography. Two phenolic acids and three flavonoids were identified by nuclear magnetic resonance spectroscopy, namely Ferulic acid (1), p-Hydroxycinnamic acid (2), Hesperidin (3), Formononetin (4), and Quercetin (5). At the same time, the gentamicin-induced nephrotoxicity of zebrafish was used as a model for the first time. The antioxidant activity of these derivatives with good antioxidant activity screened from free radical scavenging experiments in vitro (DPPH and ABTS) was evaluated in vivo, including protein levels (LPO, NO, GSH, and SOD), kidney injury factor (KIM-1), zebrafish kidney pathology and real-time PCR. The results showed that metabolites 1, 3, and 5 had strong antioxidant activity, and oxidative stress in renal tissue was significantly reduced; KIM-1, TNF-α, and IL-6 mRNA expression in a dose-dependent manner, which preliminarily revealed the protective effect of the secondary metabolites of QS on nephrotoxicity, and preliminarily discussed the structure-activity relationship. This study provides an experimental basis for further exploring the mechanism of QS in the kidney.
Subject(s)
Antioxidants , Gentamicins , Kidney Diseases , Kidney , Oxidative Stress , Plant Extracts , Quercus , Zebrafish , Animals , Gentamicins/toxicity , Plant Extracts/pharmacology , Plant Extracts/chemistry , Quercus/chemistry , Antioxidants/pharmacology , Antioxidants/metabolism , Kidney/drug effects , Kidney/metabolism , Kidney/pathology , Kidney Diseases/chemically induced , Kidney Diseases/prevention & control , Kidney Diseases/metabolism , Kidney Diseases/pathology , Oxidative Stress/drug effects , Secondary Metabolism , Disease Models, AnimalABSTRACT
We studied the effect of antibiotic gentamicin at concentrations of 0.05, 0.1, 0.2, 0.4, and 1 mg/ml on the maintenance of sperm motility of the common toad Bufo bufo during cold storage of spermic urine samples at 4°C. Parameters of sperm motility during storage of samples with gentamicin at concentrations of 0.05-0.4 mg/ml did not differ significantly, but were higher (p<0.0001) than in the control (storage without antibiotic). Gentamicin at a concentration of 1 mg/ml had a negative effect on sperm motility. After 2 weeks of storage of toad spermic urine samples with gentamicin, the largest number of sperm was preserved when using antibiotic at a concentration of 0.4 mg/ml.
Subject(s)
Anti-Bacterial Agents , Bufo bufo , Gentamicins , Semen Preservation , Sperm Motility , Spermatozoa , Animals , Gentamicins/pharmacology , Male , Sperm Motility/drug effects , Spermatozoa/drug effects , Semen Preservation/methods , Semen Preservation/veterinary , Anti-Bacterial Agents/pharmacologyABSTRACT
Although recent propagation of carbapenemase-producing Enterobacterales (CPE) has become a problem worldwide, the picture of CPE infection in Japan has not fully been elucidated. In this study, we examined clinical and microbiological characteristics of invasive CPE infection occurring at 8 hospitals in Minami Ibaraki Area between July 2001 to June 2017. Of 7294 Enterobacterales strains isolated from independent cases of bacteremia and/or meningitis, 10 (0.14%) were CPE (8 Enterobacter cloacae-complex, 1 Escherichia coli, and 1 Edwardsiella tardaï¼, all of which had the blaIMP-1 gene and susceptible to gentamicin and trimethoprim/sulfamethoxazole. These strains were isolated from 7 adult and 2 infant bacteremia (1 infant patient developed CPE bacteremia twice) after 2007. The most common portal of entry was intravenous catheters. All of the adult patients were recovered, while the infant patients eventually died. Genomic analyses showed that the 8 E. cloacae-complex strains were classified into 5 groups, each of which was exclusively detected in specific facilities at intervals of up to 3 years, suggesting persistent colonization in the facilities. This study showed that invasive CPE infection in the area was rare, caused by IMP-1-type CPE having susceptibility to various antibiotics, and nonfatal among adult patients.
Subject(s)
Anti-Bacterial Agents , Bacteremia , Bacterial Proteins , Enterobacteriaceae Infections , Microbial Sensitivity Tests , beta-Lactamases , Humans , Japan/epidemiology , Bacteremia/microbiology , Bacteremia/drug therapy , Bacteremia/epidemiology , Enterobacteriaceae Infections/microbiology , Enterobacteriaceae Infections/epidemiology , Enterobacteriaceae Infections/drug therapy , beta-Lactamases/genetics , beta-Lactamases/metabolism , Male , Female , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Infant , Middle Aged , Adult , Aged , Enterobacter cloacae/genetics , Enterobacter cloacae/drug effects , Enterobacter cloacae/isolation & purification , Gentamicins/pharmacology , Gentamicins/therapeutic use , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use , Trimethoprim, Sulfamethoxazole Drug Combination/pharmacology , Aged, 80 and over , Carbapenem-Resistant Enterobacteriaceae/genetics , Carbapenem-Resistant Enterobacteriaceae/isolation & purificationABSTRACT
Metabolic reprogramming mediates antibiotic efficacy. However, metabolic adaptation of microbes evolving from antibiotic sensitivity to resistance remains undefined. Therefore, untargeted metabolomics was conducted to unveil relevant metabolic reprogramming and potential intervention targets involved in gentamicin resistance. In total, 61 metabolites and 52 metabolic pathways were significantly altered in gentamicin-resistant E. coli. Notably, the metabolic reprogramming was characterized by decreases in most metabolites involved in carbohydrate and amino acid metabolism, and accumulation of building blocks for nucleotide synthesis in gentamicin-resistant E. coli. Meanwhile, fatty acid metabolism and glycerolipid metabolism were also significantly altered in gentamicin-resistant E. coli. Additionally, glycerol, glycerol-3-phosphate, palmitoleate, and oleate were separately defined as the potential biomarkers for identifying gentamicin resistance in E. coli. Moreover, palmitoleate and oleate could attenuate or even abolished killing effects of gentamicin on E. coli, and separately increased the minimum inhibitory concentration of gentamicin against E. coli by 2 and 4 times. Furthermore, palmitoleate and oleate separately decreased intracellular gentamicin contents, and abolished gentamicin-induced accumulation of reactive oxygen species, indicating involvement of gentamicin metabolism and redox homeostasis in palmitoleate/oleate-promoted gentamicin resistance in E. coli. This study identifies the metabolic reprogramming, potential biomarkers and intervention targets related to gentamicin resistance in bacteria.
Subject(s)
Anti-Bacterial Agents , Drug Resistance, Bacterial , Escherichia coli , Fatty Acids, Monounsaturated , Gentamicins , Oleic Acid , Gentamicins/pharmacology , Gentamicins/metabolism , Escherichia coli/metabolism , Escherichia coli/drug effects , Escherichia coli/genetics , Oleic Acid/metabolism , Oleic Acid/pharmacology , Drug Resistance, Bacterial/drug effects , Anti-Bacterial Agents/pharmacology , Fatty Acids, Monounsaturated/metabolism , Fatty Acids, Monounsaturated/pharmacology , Microbial Sensitivity Tests , Metabolomics/methods , Metabolic Networks and Pathways/drug effects , Reactive Oxygen Species/metabolism , Up-Regulation/drug effectsABSTRACT
BACKGROUND: Antimicrobial resistance (AMR) is nowadays a major emerging challenge for public health worldwide. The over- and misuse of antibiotics, including those for cell culture, are promoting AMR while also encouraging the research and employment of alternative drugs. The addition of antibiotics to the cell media is strongly recommended in sperm preservation, being gentamicin the most used for boar semen. Because of its continued use, several bacterial strains present in boar semen have developed resistance to this antibiotic. Antimicrobial peptides and proteins (AMPPs) are promising candidates as alternative antibiotics because their mechanism of action is less likely to promote AMR. In the present study, we tested two AMPPs (lysozyme and nisin; 50 and 500 µg/mL) as possible substitutes of gentamicin for boar semen preservation up to 48 h of storage. RESULTS: We found that both AMPPs improved sperm plasma membrane and acrosome integrity during semen storage. The highest concentration tested for lysozyme also kept the remaining sperm parameters unaltered, at 48 h of semen storage, and reduced the bacterial load at comparable levels of the samples supplemented with gentamicin (p > 0.05). On the other hand, while nisin (500 µg/mL) reduced the total Enterobacteriaceae counts, it also decreased the rapid and progressive sperm population and the seminal oxidation-reduction potential (p < 0.05). CONCLUSIONS: The protective effect of lysozyme on sperm function together with its antimicrobial activity and inborn presence in body fluids, including semen and cervical mucus, makes this enzyme a promising antimicrobial agent for boar semen preservation.
Subject(s)
Anti-Bacterial Agents , Muramidase , Nisin , Semen Preservation , Animals , Semen Preservation/veterinary , Semen Preservation/methods , Male , Anti-Bacterial Agents/pharmacology , Swine , Muramidase/pharmacology , Nisin/pharmacology , Semen/drug effects , Spermatozoa/drug effects , Antimicrobial Peptides/pharmacology , Cell Membrane/drug effects , Gentamicins/pharmacology , Acrosome/drug effectsABSTRACT
Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is a serious clinical challenge with high mortality rates. Antibiotic combination therapy is currently used in cases of persistent infection; however, the limited development of new antibiotics will likely increase the need for combination therapy, and better methods are needed for identifying effective combinations for treating persistent bacteremia. To identify pairwise combinations with the most consistent potential for benefit compared to monotherapy with a primary anti-MRSA agent, we conducted a systematic study with an in vitro high-throughput methodology. We tested daptomycin and vancomycin each in combination with gentamicin, rifampicin, cefazolin, and oxacillin, and ceftaroline with daptomycin, gentamicin, and rifampicin. Combining cefazolin with daptomycin lowered the daptomycin concentration required to reach 95% growth inhibition (IC95) for all isolates tested and lowered daptomycin IC95 below the sensitivity breakpoint for five out of six isolates that had daptomycin minimum inhibitory concentrations at or above the sensitivity breakpoint. Similarly, vancomycin IC95s were decreased when vancomycin was combined with cefazolin for 86.7% of the isolates tested. This was a higher percentage than was achieved by adding any other secondary antibiotic to vancomycin. Adding rifampicin to daptomycin or vancomycin did not always reduce IC95s and failed to produce synergistic interaction in any of the isolates tested; the addition of rifampicin to ceftaroline was frequently synergistic and always lowered the amount of ceftaroline required to reach the IC95. These analyses rationalize further in vivo evaluation of three drug pairs for MRSA bacteremia: daptomycin+cefazolin, vancomycin+cefazolin, and ceftaroline+rifampicin.IMPORTANCEBloodstream infections caused by methicillin-resistant Staphylococcus aureus (MRSA) have a high mortality rate despite the availability of vancomycin, daptomycin, and newer antibiotics including ceftaroline. With the slow output of the antibiotic pipeline and the serious clinical challenge posed by persistent MRSA infections, better strategies for utilizing combination therapy are becoming increasingly necessary. We demonstrated the value of a systematic high-throughput approach, adapted from prior work testing antibiotic combinations against tuberculosis and other mycobacteria, by using this approach to test antibiotic pairs against a panel of MRSA isolates with diverse patterns of antibiotic susceptibility. We identified three antibiotic pairs-daptomycin+cefazolin, vancomycin+cefazolin, and ceftaroline+rifampicin-where the addition of the second antibiotic improved the potency of the first antibiotic across all or most isolates tested. Our results indicate that these pairs warrant further evaluation in the clinical setting.
Subject(s)
Anti-Bacterial Agents , Bacteremia , Daptomycin , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Rifampin , Staphylococcal Infections , Vancomycin , beta-Lactams , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Bacteremia/drug therapy , Bacteremia/microbiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Humans , Staphylococcal Infections/drug therapy , Staphylococcal Infections/microbiology , Daptomycin/pharmacology , Daptomycin/therapeutic use , Vancomycin/pharmacology , beta-Lactams/pharmacology , beta-Lactams/therapeutic use , Rifampin/pharmacology , Rifampin/therapeutic use , Ceftaroline , Cephalosporins/pharmacology , Cephalosporins/therapeutic use , Cefazolin/pharmacology , Cefazolin/therapeutic use , Drug Therapy, Combination , Drug Synergism , Oxacillin/pharmacology , Gentamicins/pharmacology , Gentamicins/therapeutic useABSTRACT
In recent years, the evolution of antibiotic resistance has led to the inefficacy of several antibiotics, and the reverse of resistance was a novel method to solve this problem. We previously demonstrated that matrine (Mat) and berberine hydrochloride (Ber) had a synergistic effect against multidrug-resistant Escherichia coli (MDREC). This study aimed to demonstrate the effect of Mat combined with Ber in reversing the resistance of MDREC. The MDREC was sequenced passaged in the presence of Mat, Ber, and a combination of Mat and Ber, which did not affect its growth. The reverse rate was up to 39.67% after MDREC exposed to Mat + Ber for 15 days. The strain that reversed resistance was named drug resistance reversed E. coli (DRREC) and its resistance to ampicillin, streptomycin, gentamicin, and tetracycline was reversed. The MIC of Gentamicin Sulfate (GS) against DRREC decreased 128-fold to 0.63 µg/mL, and it was stable within 20 generations. Furthermore, the susceptible phenotype of DRREC remained stable within 20 generations, as well. The LD50 of DRREC for chickens was 8.69 × 109 CFU/mL. qRT-PCR assays revealed that the transcript levels of antibiotic-resistant genes and virulence genes in the DRREC strain were significantly lower than that in the MDREC strain (P < 0.05). In addition, GS decreased the death, decreased the bacterial loading in organs, alleviated the injury of the spleen and liver, and decreased the cytokine levels in the chickens infected by the DRREC strain. In contrast, the therapeutic effect of GS in chickens infected with MDREC was not as evident. These findings suggest that the combination of Mat and Ber has potential for reversing resistance to MDREC.