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IBaCC was also potent in vivo against human hookworm infections in hamsters. IBaCC production was successfully scaled to 350 liters at a contract manufacturing facility. A simple fit-for-purpose formulation to protect against stomach digestion and powdered IBaCC were successfully made and used against GINs in hamsters and mice. A pilot histopathology study and blood chemistry workup showed that five daily consecutive doses of 200 mg/kg body weight Cry5B IBaCC (the curative single dose is 40 mg/kg) was nontoxic to hamsters and completely safe. IBaCC is a safe, inexpensive, highly effective, easy-to-manufacture, and scalable anthelmintic that is practical for MDA and represents a new paradigm for treating human GINs.Ganciclovir is indicated for curative or preventive treatment of cytomegalovirus (CMV) infections. This study aimed to characterize ganciclovir pharmacokinetics, following intravenous ganciclovir and oral valganciclovir administration, to optimize dosing schemes. All children aged less then 18 years receiving ganciclovir or valganciclovir were included in this study. Pharmacokinetics were described using nonlinear mixed-effect modeling. Monte Carlo simulations were used to optimize the dosing regimen to maintain the area under the concentration-time curve (AUC) in the preventive or therapeutic target. Among the 105 children (374 concentration-time observations) included, 78 received intravenous (i.v.) ganciclovir, 19 received oral valganciclovir, and 6 received both drugs. A two-compartment model with first-order absorption for valganciclovir and first-order elimination best described the data. An allometric model was used to describe the bodyweight (BW) effect. Estimated glomerular filtration rate (eGFR) and medical status of critically ill children were significantly associated with ganciclovir elimination. Recommended doses were adapted for prophylactic treatment. To obtain a therapeutic exposure, doses should be increased to 40 mg/kg of body weight/day oral or 15 to 20 mg/kg/day i.v. in children with normal eGFR and to 56 mg/kg/day oral or 20 to 25 mg/kg/day i.v. in children with augmented eGFR. These doses should be prospectively confirmed, and therapeutic drug monitoring could be used to refine them individually. (This study has been registered at ClinicalTrials.gov under identifier NCT02539407.).Burkholderia ubonensis, a nonpathogenic soil bacterium belonging to the Burkholderia cepacia complex (Bcc), is highly resistant to some clinically significant antibiotics. The concern is that B. ubonensis may serve as a resistance reservoir for Bcc or B. pseudomallei complex (Bpc) organisms that are opportunistic human pathogens. Using a B. ubonensis strain highly resistant to tetracycline (MIC, ≥256 µg/ml), we identified and characterized tetA(64) that encodes a novel tetracycline-specific efflux pump of the major facilitator superfamily. TetA(64) and associated TetR(64) regulator expression are induced by tetracyclines. Although TetA(64) is the primary tetracycline and doxycycline resistance determinant, maximum tetracycline and doxycycline resistance requires synergy between TetA(64) and the nonspecific AmrAB-OprA resistance nodulation cell division efflux pump. TetA(64) does not efflux minocycline, tigecycline, and eravacycline. Comprehensive screening of genome sequences showed that TetA(64) is unequally distributed in the Bcc and absent from the Bpc. It is present in some major cystic fibrosis pathogens, like Burkholderia cenocepacia, but absent from others like Burkholderia multivorans The tetR(64)-tetA(64) genes are located in a region of chromosome 1 that is highly conserved in Burkholderia sp. Because there is no evidence for transposition, the tetR(64)-tetA(64) genes may have been acquired by homologous recombination after horizontal gene transfer. Although Burkholderia species contain a resident multicomponent efflux pump that allows them to respond to tetracyclines up to a certain concentration, the acquisition of the single-component TetA(64) by some species likely provides the synergy that these bacteria need to defend against high tetracycline concentrations in niche environments.Previously, we reported the potent activity of a novel spiropyrimidinetrione, zoliflodacin, against Neisseria gonorrhoeae isolates collected in 2013 from symptomatic men in Nanjing, China. Here, we investigated trends of susceptibilities to zoliflodacin in 986 isolates collected from men between 2014 and 2018. N. gonorrhoeae isolates were tested for susceptibility to zoliflodacin and seven other antibiotics. Mutations in the gyrA, gyrB, parC, parE, and mtrR genes were determined by PCR and sequencing. The MICs of zoliflodacin ranged from ≤0.002 to 0.25 mg/liter; the overall MIC50 and MIC90 were 0.06 mg/liter and 0.125 mg/liter, respectively, in 2018, increasing 2-fold from 2014. However, the percentage of isolates with lower zoliflodacin MICs declined in each year sequentially, while the percentage with higher MICs increased yearly (P ≤ 0.00001). read more All isolates were susceptible to spectinomycin but resistant to ciprofloxacin (MIC ≥ 1 mg/liter); 21.2% (209/986) were resistant to azithromycin (≥1 mg/liter), 43.4% (428/986) were penicillinase-producing N. gonorrhoeae (PPNG), 26.9% (265/986) were tetracycline-resistant N. gonorrhoeae (TRNG), and 19.4% (191/986) were multidrug-resistant (MDR) isolates. 202 isolates with the lowest (≤0.002 to 0.015 mg/liter) and highest (0.125 to 0.25 mg/liter) zoliflodacin MICs were quinolone resistant with double or triple mutations in gyrA; 193/202 (95.5%) also had mutations in parC There were no D429N/A and/or K450T mutations in GyrB identified in the 143 isolates with higher zoliflodacin MICs; an S467N mutation in GyrB was identified in one isolate. We report that zoliflodacin continues to have excellent in vitro activity against clinical gonococcal isolates, including those with high-level resistance to ciprofloxacin, azithromycin, and extended-spectrum cephalosporins.Vancomycin is a synthetic antibiotic effective against Gram-positive pathogens. Although the clinical applicability of vancomycin for infants has been increasing, the pharmacokinetic data for vancomycin in extremely low-birth-weight infants are limited. The aim of this study was to construct a population pharmacokinetics model for vancomycin in extremely-low-birth-weight infants and establish an optimal dosage regimen. We enrolled children aged less than 1 year with a birth weight of less than 1,000 g and body weight at vancomycin prescription of less than 1,500 g. Pharmacokinetic data from 19 patients were analyzed, and a population pharmacokinetics model was developed using nonlinear mixed-effects modeling software. Goodness-of-fit plots, a nonparametric bootstrap analysis, and a prediction-corrected visual predictive check were employed to evaluate the final model. link2 The dosage regimen was optimized based on the final model. The pharmacokinetic data fit a one-compartment model with first-order elimination, and body weight and estimated serum creatinine level were used as significant covariates. In a simulation using the final model, the optimal dosage regimen, especially when the serum creatinine level (>0.6 mg/dl) was high, was 5.0 to 7.5 mg/kg of body weight twice a day every 12 h; this was required to reduce the dosage compared with that in previous studies. The recommended doses based on the current target time course concentration curves may not be appropriate for extremely-low-birth-weight infants.Mycobacterium abscessus exhibits Arr (ADP-ribosyltransferase)-dependent rifampin resistance. In apparent contrast, rifabutin (RBT) has demonstrated promising activity in M. abscessus infection models, implying that RBT might not be inactivated by Arr. RBT susceptibility testing of M. abscessusΔarr revealed a strongly decreased MIC. Our findings suggest that the efficacy of RBT might be enhanced by rendering RBT resilient to Arr-dependent modification or by blocking M. abscessus Arr activity.The approval of aztreonam lysine for inhalation solution (AZLI) raised concerns that additional antibiotic exposure would potentially affect the susceptibility profiles of Pseudomonas aeruginosa isolates from cystic fibrosis (CF) patients. This 5-year, prospective, observational study tracked susceptibility changes and clinical outcomes in CF patients in the United States with chronic P. aeruginosa infection. Sputum cultures were collected annually (2011 to 2016). The primary study endpoint was the proportion of subjects whose least susceptible P. aeruginosa isolate had an aztreonam MIC that was >8 μg/ml (parenteral breakpoint) and increased ≥4-fold compared with the least susceptible isolate from the previous year. Annualized data for pulmonary exacerbations, hospitalizations, and percent of predicted forced expiratory volume in 1 s (FEV1% predicted) were obtained from the CF Foundation Patient Registry and compared between subjects meeting and those not meeting the primary endpoint. A total of 510 subjects were enrolled; 334 (65%) completed the study. A consistent proportion of evaluable subjects (13 to 22%) met the primary endpoint each year, and AZLI use during the previous 12 months was not associated with meeting the primary endpoint. While the annual declines in lung function were comparable for subjects meeting and those not meeting the primary endpoint, more pulmonary exacerbations and hospitalizations were experienced by those who met it. The aztreonam susceptibility of P. aeruginosa remained consistent during the 5-year study. The relationship between P. aeruginosa isolate susceptibilities and clinical outcomes is complex; reduced susceptibility was not associated with an accelerated decline in lung function but was associated with more exacerbations and hospitalizations, likely reflecting increased overall antibiotic exposure. (This study has been registered at ClinicalTrials.gov under identifier NCT01375036.).Acinetobacter baumannii is recognized as an urgent public health threat by the Centers for Disease Control and Prevention (CDC). Current treatment options are scarce, particularly against carbapenem-resistant Acinetobacter baumannii (CRAB). We simulated the impact of minocycline standard (200 mg load + 100 mg Q12h) and high (700 mg load + 350 mg Q12h) doses, polymyxin B (2.5 mg/kg Q12h), sulbactam (1 g Q6h and 9 g/24 h as continuous infusion), and meropenem (intermittent 1 or 2 g Q8h and 6 g/24 h as continuous infusion) alone or in combination against CRAB and non-CRAB isolates by simulating human therapeutic dosing regimens in a 72-h, in vitro pharmacodynamic (IVPD) model. link3 There were no monotherapy regimens that demonstrated bactericidal activity against the tested non-CRAB and CRAB strains. Resistance development was common in monotherapy regimens. Against the CRAB isolate, the triple combination of high-dose minocycline (fAUC/MIC 21.2), polymyxin B (fAUC/MIC 15.6), and continuous-infusion sulbactam (67% T>MIC) was the most consistently active regimen. Against non-CRAB, the triple therapy regimen of high-dose minocycline (fAUC/MIC 84.8) with continuous-infusion meropenem (100% T>MIC) and continuous-infusion sulbactam (83% T>MIC), as well as the double therapy of high-dose minocycline (fAUC/MIC 84.8) with continuous-infusion meropenem (100% T>MIC), resulted in persistently bactericidal activity. In conclusion, triple therapy with high-dose minocycline, continuous-infusion sulbactam, and polymyxin B produced the most significant kill against the carbapenem-resistant Acinetobacter baumannii, with no regrowth and minimal resistance development.

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