Search

BACKGROUND: The obligate intracellular bacterial family Chlamydiaceae comprises a number of different species that cause disease in various vertebrate hosts including humans. Chlamydia suis, primarily found in the gastrointestinal tract of pigs, is the only species of the Chlamydiaceae family to have naturally gained tetracycline resistance (TetR), through a genomic island (Tet-island), integrated into the middle of chromosomal invasin-like gene inv. Previous studies have hypothesised that the uptake of the Tet-island from a host outside the Chlamydiaceae family was a unique event, followed by spread among C. suis through homologous recombination. In vitro recombination studies have shown that Tet-island exchange between C. suis strains is possible. Our aim in this study was to gain a deeper understanding of the interclade recombination of the Tet-island, among currently circulating C. suis field strains compared to in vitro-generated recombinants, using published whole genome sequences of C. suis field strains (n = 35) and in vitro-generated recombinants (n = 63). RESULTS: We found that the phylogeny of inv better reflected the phylogeny of the Tet-island than that of the whole genome, supporting recombination rather than site-specific insertion as the means of transfer. There were considerable differences between the distribution of recombinations within in vitro-generated strains compared to that within the field strains. These differences are likely because in vitro-generated recombinants were selected for a tetracycline and rifamycin/rifampicin resistant background, leading to the largest peak of recombination across the Tet-island. Finally, we found that interclade recombinations across the Tet-island were more variable in length downstream of the Tet-island than upstream. CONCLUSIONS: Our study supports the hypothesis that the occurrence of TetR strains in both clades of C. suis came about through interclade recombination after a single ancestral horizontal gene transfer event.

Purpose: To analyze the effectiveness of coating of abutments with antimicrobial agents and their influence on the physicochemical and biologic properties of the coated materials. Materials and Methods: This work was registered in Open Science Framework (osf.io/6tkcp) and followed the PRISMA protocols. A search of two independent reviewers of articles published up to October 29, 2021, was performed in the Embase, PubMed, Science Direct, and Scopus databases. Results: The databases found a total of 1,474 references. After excluding the duplicates, 1,050 remained. After reading the titles and abstracts and applying the inclusion criteria, 13 articles remained and were read in full. A total of 8 articles were included in this systematic review. Different antimicrobial agents have been used to coat abutments, including graphene oxide, polydopamine, titanium and zirconium nitride, lactoferrin, tetracycline, silver, and doxycycline with varied release times. Titanium-coated silver showed a better antimicrobial agent release time of up to 28 days. Chemical analysis confirmed the presence of antimicrobials on the surface after coating. Different pathogenic microorganisms, such as Streptococcus sanguinis, Streptococcus oralis, and Staphylococcus aureus, were inhibited when in contact with the coated surface. Conclusions: This review showed that there is still no consensus on which is the better antimicrobial agent and which coated materials have the better performance. However, the association of surface coating of abutments with antimicrobials is feasible and can benefit many patients, which can support their clinical use to favor the healing process and prevent infections that can lead to treatment failure with dental implants. [ABSTRACT FROM AUTHOR]

Bovine respiratory disease (BRD) is the leading cause of mortality and antimicrobial drug (AMD) use in weaned dairy heifers. Limited information is available regarding antimicrobial resistance (AMR) in respiratory bacteria in this population. This study determined AMR gene presence in 326 respiratory isolates (Pasteurella multocida, Mannheimia haemolytica, and Histophilus somni) from weaned dairy heifers using whole genome sequencing. Concordance between AMR genotype and phenotype was determined. Twenty-six AMR genes for 8 broad classes of AMD were identified. The most prevalent, medically important AMD classes used in calf rearing, to which these genes predict AMR among study isolates were tetracycline (95%), aminoglycoside (94%), sulfonamide (94%), beta-lactam (77%), phenicol (50%), and macrolide (44%). The co-occurrence of AMR genes within an isolate was common; the largest cluster of gene co-occurrence encodes AMR to phenicol, macrolide, elfamycin, β-lactam (cephalosporin, penam cephamycin), aminoglycoside, tetracycline, and sulfonamide class AMD. Concordance between genotype and phenotype varied (Matthews Correlation Coefficient ranged from -0.57 to 1) by bacterial species, gene, and AMD tested, and was particularly poor for fluoroquinolones (no AMR genes detected) and ceftiofur (no phenotypic AMR classified while AMR genes present). These findings suggest a high genetic potential for AMR in weaned dairy heifers; preventing BRD and decreasing AMD reliance may be important in this population.

Genetic screening of pools of mutants can reveal genetic determinants involved in complex biological interactions, processes, and systems. We previously constructed two single-gene deletion resources for Salmonella enterica serovar Typhimurium 14028s in which kanamycin (KanR) and chloramphenicol (CamR) cassettes were used to replace non-essential genes. We have now used lambda-red recombination to convert the antibiotic cassettes in these resources into a tetracycline-resistant (TetR) version where each mutant contains a different 21-base barcode flanked by Illumina Read1 and Read2 primer sequences. A motility assay of a pool of the entire library, followed by a single-tube processing of the bacterial pellet, PCR, and sequencing, was used to verify the performance of the barcoded TetR collection. The new resource is useful for experiments with defined subsets of barcoded mutant strains where biological bottlenecks preclude high numbers of founder bacteria, such as in animal infections. The TetR version of the library will also facilitate the construction of triple mutants by transduction. The resource of 6197 mutants covering 3490 genes is deposited at Biological and Emerging Infections Resources (beiresources.org).

BACKGROUND: Comprehensive descriptions of equids with granulocytic anaplasmosis (EGA) with neurologic or muscle disease and other atypical presentations are scarce in the literature. OBJECTIVE: Describe the clinical signs, laboratory findings, treatment, and outcome of equids with EGA with emphasis on neurologic and muscle disease. ANIMALS: Thirty-eight horses, 1 donkey. METHODS: Retrospective study. Equids with EGA were included. The electronic data base was searched from January 2000 to December 2022 using the words anaplasmosis, ehrlichiosis, granulocytic, and rickettsia. Signalment and clinical data were reviewed. Data were evaluated for normality using Shapiro-Wilk test. Parametric and nonparametric statistics were used for normally and non-normally distributed data. RESULTS: Common (41%) and other (59%) presentations were seen in horses ≥ 4 years of age (median, 14 years) with an overrepresentation of males (77%). Neurologic disease was common (41%), mainly presenting as diffuse symmetrical proprioceptive ataxia. Brain disease was less common manifesting as obtundation and cranial nerve deficits. Muscle disease was less common, with QH breeds with the variant causing myosin heavy chain myopathy (MYHM) having severe disease. Cavitary effusion, cardiomyopathy and disseminated intravascular coagulation (DIC) were uncommon. Clinical laboratory results varied depending on disease stage. Muscle enzyme activities were significantly higher in horses with muscle disease. Outcome was favorable with prompt tetracycline treatment. Death and long-term sequelae were not reported. CONCLUSIONS AND CLINICAL IMPORTANCE: Common and atypical presentations of EGA have a favorable outcome with prompt tetracycline treatment. Quarter horse breeds with muscle disease should be genotyped for MYHM.

This study investigated the prevalence and antimicrobial resistance (AMR) of Escherichia coli (E. coli) in Nile tilapia from fresh markets and supermarkets. A total of samples (n = 828) were collected from Nile tilapia including fish flesh (n = 276), liver and kidney (n = 276), and intestine (n = 276). Overall prevalence of fecal coliforms (61.6%) and E. coli (53.0%) were observed. High prevalence of E. coli was found in the intestine (71.4%), followed by the liver and kidney (45.7%). The highest prevalence of resistance was commonly found against tetracycline (78.5%), ampicillin (72.8%), and sulfamethoxazole (45.6%) with resistance to only tetracycline (15.2%) as the most common antibiogram. The prevalence of multidrug resistance (MDR) (54.4%) and Extended-spectrum beta-lactamases (ESBLs) (5.7%) were examined. The predominant virulence genes (n = 158) were st (14.6%), followed by eaeA (0.6%). The blaTEM (73.4%), tetA (65.2%), and qnrS (57.6%). There is statistical significance between Nile tilapia from fresh markets and supermarkets. Based on logistic regression analysis, ampicillin-resistant E. coli was statistically associated with the phenotypic resistance to tetracycline and trimethoprim, and the presence of blaTEM and tetA (p < 0.05). Further investigation of AMR transference and their mechanisms is needed for AMR control.

Recently, metal–organic framework (MOF)/peroxymonosulfate (PMS) systems have shown great potential in the treatment of antibiotic-containing wastewater. Herein, a Co–Ti-400 Fenton-like catalyst was synthesized by calcining Co-doped MIL-125(Ti) (Co–Ti) at 400 °C. Co–Ti-400 revealed an excellent catalytic performance for tetracycline hydrochloride (TCH) removal by activating PMS in a wide pH range (pH = 2–11). Significantly, 96.2% of TCH was removed in 1 hour over the catalyst (70 mg L−1 of TCH, 0.2 g L−1 of catalyst, 1 mM PMS, and pH = 4). Furthermore, Co–Ti-400 exhibited enhanced catalytic activity and stability in four cycles compared to the uncalcined sample (Co–Ti). Radicals (·OH, O2˙−, and SO4˙−) and 1O2 were proved to be the main active species during TCH degradation. Notably, Co–Ti-400/PMS showed good anti-interference towards inorganic salts in water. A reasonable degradation mechanism was proposed based on LC-MS analysis. With its exceptional catalytic performance and broad pH adaptability, Co–Ti-400 can be considered a potential catalyst for antibiotic removal. [ABSTRACT FROM AUTHOR]

N‐S co‐doped magnetic biochar (NSMBC) was synthesized by a two‐step pyrolysis technique and used for the degradation of tetracycline (TC) by activated persulfate (peroxomonosulfate [PMS]). Batch experiments showed that the pyrolysis temperature and doping ratio affected the catalytic performance of NSMBC. The degradation rate of TC in the NSMBC/PMS system prepared at 350°C with a doping ratio of 33% was up to 94.50%, and the system exhibited strong pH adaptability and resistance to environmental interference. The results of free radical burst and electron paramagnetic resonance (EPR) spectroscopy experiments indicated the free radical pathway (SO4•−) for TC degradation. In addition, NSMBC has good stability and excellent magnetic properties favorable for separation and recovery. This study not only provides a new idea for the synthesis of efficient and stable catalysts but also provides a green pathway for the resourceization of pomelo peel waste. [ABSTRACT FROM AUTHOR]

• Earthworms and LAB synergistically enhance TC degradation efficiency. • LAB alleviate the biological stress of TC on earthworms. • Various TC doses significantly affect earthworm body bacterial communities. • High TC doses can elevate pathogenic bacteria dominance. Tetracycline is an antibiotic with extensive veterinary use in the livestock industry. However, their widespread application poses risks to soil health as residue in livestock feces, and their removal is crucial for sustainable soil-ecosystem development. Physical and chemical approaches to extract tetracycline may have adverse effects on soil ecosystems, but no studies have thus far examined the potential for biological methods, such as collective degradation action of soil fauna. Thus, this study aimed to investigate the synergistic effects of lactic acid bacteria (LAB) and earthworms (Eisenia fetida) on biodegradation of tetracycline residues in sheep manure. We assessed earthworm biomass, tetracycline residue, and bacterial communities in both earthworm intestines and vermicompost. Earthworm biomass and tetracycline degradation efficiency increased significantly with LAB addition, with a degradation rate of up to 80.16%. This increase may be attributable to LAB acting as electron donors to spur tetracycline degradation. Additionally, we noted that tetracycline presence significantly influenced bacterial communities in earthworm intestines and vermicompost, elevating the abundance of potential pathogenic bacteria (e.g., Flavobacterium , Gammaproteobacteria , and Enterobacteriaceae). This finding suggests that heightened environmental stress from antibiotics could actually facilitate the growth of less prevalent bacteria, including potential pathogens. In conclusion, our study provides evidence supporting the effectiveness of LAB and earthworms in degrading tetracycline residues. In particular, LAB appears to mitigate stress from tetracycline exposure in earthworms, thus increasing their vermicomposting efficacy. Our work has important implications for soil management, with the potential to enhance pollution clean-up rates while minimizing negative side-effects to soil microbial communities. [ABSTRACT FROM AUTHOR]

Photocatalysis is regarded as a potent alternative to conventional treatment methods with low removal efficiency (e.g., activated sludge process) against refractory/recalcitrant antibiotics in wastewater. Here, the potential utility of bismuth oxyiodide (BiOI)-based materials has been evaluated as visible-light–driven photocatalysts (bandgap energy < 2.0 eV) with unique optical structure for the enhanced treatment of tetracyclines (TCs) as a representative antibiotic product. The effects of key modification strategies (e.g., elemental doping and heterojunction formation) on the photocatalytic activity of BiOI-based photocatalysts are assessed against TCs in terms of the key performance metrics such as quantum efficiency (QE) and space-time yield (STY). This review also highlights the challenges and promising opportunities for the photocatalytic application of BiO-based materials against TCs in real effluents. Accordingly, zinc-doped BiOI is recognized to have the maximum efficiency with QE of 2.95 × 10−5 molecules photon−1 and STY of 2.95 × 10−7 molecules photon−1 mg−1. This review is expected to help deepen the exploration path to the construction of efficient BiOI-based systems based on their performance evaluation along with the discussions on their perspectives. [ABSTRACT FROM AUTHOR]

An electrochemical aptasensor was established for the fast and sensitive determination of tetracycline based on the synergistic effect of MoS2-thionine nanocomposite and aptamer. The glassy carbon electrode was coated with MoS2 nanosheets of thionine to immobilize the tetracycline aptamer. In the absence of tetracycline, large quantities of thionin were loaded on the surface of the MoS2 nanosheet to serve as the electrochemical probe. After tetracycline was added to the surface of the electrode, an aptamer analyte complex was produced on the modified electrode. Through intercalation and electrostatic interactions, the complex was substantially adsorbed onto thionine, and the peak currents of the redox signal of thionine decreased. Therefore, the concentration of tetracycline was monitored by the change in signal intensity. Under optimized conditions, the developed electrochemical strategy with MoS2-thionine composite and aptamer exhibited an excellent linear detection range of 1.0 nM–1.0 μΜ and a low detection limit of 0.6 nM with suitable selectivity and stability. Therefore, the fabricated platform offers great potential for food safety, medical detection, and drug analysis. [ABSTRACT FROM AUTHOR]

The overuse of antibiotics has led to severe environmental pollution, thereby making it increasingly important to efficiently degrade them. To address this, a unique S-scheme heterojunction of the In2S3/In2O3 nanocomposite was successfully constructed using hydrothermal coupled with in situ formation in this work. The optimized In2S3/In2O3 nanocomposite exhibited a significant photocatalytic degradation of tetracycline (TC), achieving an 83% removal rate within 60 min, with enhancements of 1.78 times for In2S3 and 1.66 times for In2O3. Characterization, experimental results, and density functional theory (DFT) calculation collectively prove the efficient transfer of photoexcited carriers between In2O3 and In2S3, coupled with the successful construction of the S-scheme heterojunction with a well-arranged band structure. A potential pathway for developing photocatalysts with exceptional antibiotic removal capabilities has been provided by enhancing their reduction and oxidation capabilities of the S-scheme heterojunction through rational structural configuration. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) constitute an assorted class of multi-dimensional materials that offer the potential to serve as luminescent sensors for the sensitive and selective detection of antibiotics in wastewater. Herein, a new Zn(II)-based MOF with the formula [Zn(PMA)0.5(bbp)·H2O·DMA] (1) (bbp = 3,5-bis(benzoimidazo-1-ly)pyridine; PMA = pyromellitic acid) was synthesized by a solvothermal method and characterized. Crystallographic analysis reveals that MOF 1 possesses a 4,4-connected net with the Schläfli symbol {32·4·52·6}2{32·42·52}. The fabricated MOF exhibited luminescent property and was employed as a luminescent sensor to sensitively and selectively detect tetracycline (TCY) antibiotic amongst thiamphenicol (THI), 2-methyl-4-chlorophenoxyacetic acid (MCPA), tetracycline (TCY), sulfamethoxazole (SMT), thiabendazole (TBZ), tinidazole (TDZ), sulfadiazine (SDZ), chloramphenicol (CAP), metamitron (MMT), and dinotefuran (DTF). Further, restoration of the emissive response of TCY@1 was achieved by adding salicylic acid with a concomitant bathochromic shift in the emissive response. The possible sensing mechanism and restoration of emissive response were assessed with the aid of theoretical calculations. [ABSTRACT FROM AUTHOR]

A process for photocatalytically synthesizing hydrogen peroxide while simultaneously degrading organic pollutants is of interest. In this study, a dendritic nanopolymer was synthesized and utilized as a photocatalyst for the production of hydrogen peroxide, which was then used in tandem with the degradation of Tetracycline (TC) and Rhodamine B (Rh B) organic pollutants under a 36 W incandescent bulb. The yield of H2O2 was measured at 8.4 mg g−1 h−1, with photocatalytic degradation rates of 93.90 % for Rh B and 72.92 % for TC. The degradation kinetics of TC and Rh B by the dendritic polymer were found to follow pseudo‐first‐order kinetics, and a higher affinity for degradation was observed for Rh B. The photocatalytic degradation mechanism of TC in a Fenton‐like system was attributed to an oxidation system involving hydrogen peroxide and ferrous ions. [ABSTRACT FROM AUTHOR]

Tetracycline (TC) has been widely used in clinical medicine and animal growth promotion due to its broad-spectrum antibacterial properties and affordable prices. Unfortunately, the high toxicity and difficult degradation rate of TC molecules make them easy to accumulate in the environment, which breaks the ecological balance and seriously threatens human health. Rapid and accurate detection of TC residue levels is important for ensuring water quality and food safety. Recently, fluorescence detection technology of TC residues has developed rapidly. Lanthanide nanomaterials, based on the high luminescence properties of lanthanide ions and the high matching with TC energy levels, are favored in the real-time trace detection of TC due to their advantages of high sensitivity, rapidity, and high selectivity. Therefore, they are considered potential substitutes for traditional detection methods. This review summarizes the synthesis strategy, TC response mechanism, removal mechanism, and applications in intelligent sensing. Finally, the development of lanthanide nanomaterials for TC fluorescence detection and removal is reasonably summarized and prospected. This review provides a reference for the establishment of a method for the accurate determination of TC content in complex food matrices. [ABSTRACT FROM AUTHOR]

Functional materials with organic/inorganic composites as the main matrix and rare earth ion complexes as the guest have shown a very broad application prospect for antibiotic sensors. However, Eu3+-complex often relies on a single fluorescence response signal, which is susceptible to changes in the detection environment and cannot simultaneously detect and remove tetracycline (TC). Herein, green fluorescent covalent two-dimensional organic framework (COF-TD) is synthesized, followed by modification of Eu3+ to synthesize COF-TD@Eu3+. In the ratiometric sensor, Eu3+ serves as the recognition site and specific response probe for TC, while COF-TD is the fluorescence reference and carrier for Eu3+. Due to the antenna effect, TC enhances the red fluorescence of Eu3+, while the green fluorescence of COF-TD remains almost stable. Based on the change of fluorescence intensity and fluorescence color from green to red, the efficient ratiometric sensing can be finished in 1 min. The developed method shows high sensitivity with a detection limit of 0.3 μM and high selectivity to TC which makes the method applicable to detect TC in traditional Chinese medicine preparations. In addition, due to the high specific surface area of COFs and specific adsorption sites, COF-TD@Eu3+ also shows good performance for TC removal. The findings show that the maximum adsorption capacity is 137.3 mg g−1 and the adsorption equilibrium is reached in 30 min. Smartphone assisted COF-TD@Eu3+ for both ratiometric fluorescence detection and detecting the absorption of TC is proposed for the first time. The molecular cryptosteganography that transforms the selective response of COF-TD@Eu3+ to binary strings is anticipated to advance utilization of nanomaterials in logic sensing and information safety. [ABSTRACT FROM AUTHOR]

Catalytic performance decline is a general issue when shaping fine powder into macroscale catalysts (e.g., beads, fiber, pellets). To address this challenge, a phenolic resin-assisted strategy was proposed to prepare porous Co/N carbon beads (ZACBs) at millimeter scale via the phase inversion method followed by confined pyrolysis. Specially, p-aminophenol–formaldehyde (AF) resin-coated zeolitic imidazolate framework (ZIF-67) nanoparticles were introduced to polyacrylonitrile (PAN) solution before pyrolysis. The thermosetting of the coated AF improved the interface compatibility between the ZIF-67 and PAN matrix, inhibiting the shrinkage of ZIF-67 particles, thus significantly improving the void structure of ZIF-67 and the dispersion of active species. The obtained ZACBs exhibited a 99.9% removal rate of tetracycline (TC) within 120 min, with a rate constant of 0.069 min−1 (2.3 times of ZIF-67/PAN carbon beads). The quenching experiments and electron paramagnetic resonance (EPR) tests showed that radicals dominated the reaction. This work provides new insight into the fabrication of high-performance MOF catalysts with outstanding recycling properties, which may promote the use of MOF powder in more practical applications. [ABSTRACT FROM AUTHOR]

Zinc cobalt oxide-zinc hydroxide (ZnCo2O4-Zn(OH)2) microspheres were successfully fabricated on carbon cloth via a sample hydrothermal method. The surface morphology of these microspheres and their efficacy in degrading methyl violet were further modulated by varying the thermal annealing temperatures. Adjusting the thermal annealing temperatures was crucial for controlling the porosity of the ZnCo₂O₄-Zn(OH)₂ microspheres, enhancing their photocatalytic performance. Various analytical techniques were utilized to evaluate the physical and chemical properties of the ZnCo2O4-Zn(OH)2 microspheres, including field-emission scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, field-emission transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis spectroscopy. Compared to untreated ZnCo2O4-Zn(OH)2 microspheres, those subjected to thermal annealing exhibited increased specific surface area and light absorption capacity, rendering them highly effective photocatalysts under UVC light exposure. Subsequent studies have confirmed the superior performance of ZnCo2O4-Zn(OH)2 microspheres as a reusable photocatalyst for degrading methyl violet and tetracycline. Furthermore, trapping experiments during the photodegradation process using ZnCo₂O₄-Zn(OH)₂ microspheres identified hydroxyl radicals (·OH) and superoxide radicals (·O₂⁻) as the primary reactive species. [ABSTRACT FROM AUTHOR]

Background The AnticFast® Beta-lactams & Tetracyclines Combo Test Kit is a qualitative two-step (2 min + 5 min) rapid lateral flow assay to detect β-lactam (penicillins and cefalosporins) and tetracycline antibiotic residues in raw commingled cows' milk. Objective The method performance was evaluated according to Commission Implementing Regulation 2021/808 and Community Reference Laboratories Residues Guidelines for the Validation of Screening Methods for Residues of Veterinary Medicines and submitted for AOAC Performance Tested Methods SM certification. Methods The AnticFast Beta-lactams & Tetracyclines Combo Test Kit was evaluated for detection capability (CCβ), selectivity, false-positive results, repeatability, robustness, suitability for various milk types and milk compositions, milks from various species, and test kit consistency and stability. Samples included milks spiked at concentrations bracketing the EU maximum residue limits (MRLs) for β-lactams and tetracyclines as well as bulk farm and tanker milks. Results The AnticFast Beta-lactams & Tetracyclines Combo Test Kit is specific for the detection of residues of β-lactams and tetracyclines in milk and does not detect residues from other antibiotic families. Interference was seen with clavulanic acid, a β-lactamase inhibitor, which was expected. The test can detect (minimum a 95% detection) all residues of β-lactams (penicillins and cepfalosporins) and tetracyclines (parent drugs and their 4-epimers) present on the EU-MRL list for milk at their respective MRL except for desfuroylceftiofur and cefalexin, with a 95% detection only above the MRL. No false positives were detected in 599 blank samples (out of 305 farm and 301 tanker load samples) tested on both channels. Five real positives were detected and confirmed on the tetracycline channel for the farm milk samples, and two positives were detected and confirmed on the β-lactam channel for the tanker samples. Robustness testing indicated that the detection in high-protein raw cows' milk and heat-treated milk types (UHT, sterilized, and reconstituted milk powder) may be slightly hampered. For substances with a detection capability well below the MRL, this interference does not cause problems since detection at MRL remains guaranteed, but care should be taken for substances with a CCβ at or near their MRL. Diminished sample flow was seen for high-fat raw cows' milk and for all other cows' milk types other than raw milk and blank ewes' milk, so sample flow should always be verified for these milk types. Conclusions Results of this validation show that the AnticFast Beta-lactams & Tetracyclines Combo Test Kit is a reliable test for rapid screening of raw cows' milk for residues of β-lactam and tetracycline antibiotics. Highlights The AnticFast Beta-lactams & Tetracyclines Combo Test Kit is an easy, reliable, robust, and highly specific test for screening of β-lactam (penicillins and cefalosporins) and tetracycline antibiotic residues in milk with incubation at room temperature. In raw cows' milk, all tetracyclines are detected below 10 µg/kg. [ABSTRACT FROM AUTHOR]

The disposal and treatment of antibiotic residues is a recognized challenge due to the huge production, high moisture content, high processing costs, and residual antibiotics, which caused environmental pollution. Antibiotic residues contained valuable components and could be recycled. Using a one-step controllable pyrolysis technique in a tubular furnace, biochar (OSOBs) was produced without the preliminary carbonization step, which was innovative and time- and cost-saving compared to traditional methods. The main aim of this study was to explore the adsorption and removal efficiency of tetracycline (TC) in water using porous biochar prepared from oxytetracycline fermentation residues in one step. A series of characterizations were conducted on the prepared biochar materials, and the effects of biochar dosage, initial tetracycline concentration, reaction time, and reaction temperature on the adsorption capacity were studied. The experimental results showed that at 298 K, the maximum adsorption capacity of OSOB-3-700 calculated by the Langmuir model reached 1096.871 mg/g. The adsorption kinetics fitting results indicated that the adsorption of tetracycline on biochar was more consistent with the pseudo-second-order kinetic model, which was a chemical adsorption. The adsorption isotherm fitting results showed that the Langmuir model better described the adsorption process of tetracycline on biochar, indicating that tetracycline was adsorbed in a monolayer on specific homogeneous active sites through chemical adsorption, consistent with the kinetic conclusions. The adsorption process occurred on the surface of the biochar containing rich active sites, and the chemical actions such as electron exchange promoted the adsorption process. [ABSTRACT FROM AUTHOR]

In this paper, we developed a paper-based fluorescent sensor using functional composite materials composed of graphene quantum dots (GQDs) coated with molecularly imprinted polymers (MIPs) for the selective detection of tetracycline (TC) in water. GQDs, as eco-friendly fluorophores, were chemically grafted onto the surface of paper fibers. MIPs, serving as the recognition element, were then wrapped around the GQDs via precipitation polymerization using 3-aminopropyltriethoxysilane (APTES) as the functional monomer. Optimal parameters such as quantum dot concentration, grafting time, and elution time were examined to assess the sensor's detection performance. The results revealed that the sensor exhibited a linear response to TC concentrations in the range of 1 to 40 µmol/L, with a limit of detection (LOD) of 0.87 µmol/L. When applied to spiked detection in actual water samples, recoveries ranged from 103.3% to 109.4%. Overall, this paper-based fluorescent sensor (MIPs@GQDs@PAD) shows great potential for portable, multi-channel, and rapid detection of TC in water samples in the future. [ABSTRACT FROM AUTHOR]

Background With the increasing prevalence of antibiotic resistance, real-world data on the optimal empirical second-line therapy for Helicobacter pylori are still limited. Objectives To evaluate the real-world efficacy of various second-line therapies for H. pylori. Patients and methods This was a retrospective population-based cohort study of all H. pylori -infected patients who had received the second-line treatment after the failure of primary clarithromycin triple therapy in Hong Kong between 2003 and 2018. The retreatment success rates of different second-line therapies were evaluated. Results A total of 7591 patients who received second-line treatment were included. Notably, the most commonly prescribed regimen was still clarithromycin triple therapy, but the frequency of use had decreased from 59.5% in 2003–06 to 28.7% in 2015–18. Concomitant non-bismuth quadruple therapy had emerged as the commonest regimen (from 3.3% to 43.9%). In a validation analysis, the sensitivity and specificity of retreatment-inferred second-line treatment failure were 88.3% and 97.1%, respectively. The overall success rate of second-line therapies was 73.6%. Bismuth quadruple therapy had the highest success rate of 85.6%, while clarithromycin triple therapy had the lowest success rate of 63.5%. Specifically, bismuth/metronidazole/tetracycline quadruple, metronidazole/tetracycline triple, levofloxacin/metronidazole/tetracycline quadruple, rifabutin/amoxicillin triple and amoxicillin/levofloxacin triple therapies had relatively higher success rates over 80%. Age, treatment duration, baseline conditions and first-line treatment used were associated with success rate. Conclusions Bismuth quadruple therapy was the most effective second-line regimen for H. pylori in this real-world study. Despite a very low success rate, clarithromycin-containing triple therapies were still commonly used as second-line regimens. [ABSTRACT FROM AUTHOR]

[Display omitted] In this study, metal-free PO 4 3− enriched g-C 3 N 4 /g-C 3 N 4 (PGCN) homojunction alginate 3D beads were developed for in-situ H 2 O 2 production under visible light. Later, the photocatalytic-self-Fenton system was integrated with peroxymonosulfate for tetracycline degradation. Initially, the PO 4 3− enriched g-C 3 N 4 (PCN) and a homojunction composed of PCN and g-C 3 N 4 (GCN) were prepared via the wet-impregnation method. Later, PGCN homojunction was formulated into 3D alginate beads through the blend-crosslinking method. The comprehensive characterization of the homojunction beads affirmed the closer contact between the semiconductors, alteration of the bandgap, faster channelization of electron-hole pairs, and improved separation of charge carriers that attributed to higher catalytic efficacy. The PGCN beads exhibited a maximum H 2 O 2 production of 535 ± 12 µM under visible light irradiation for 60 min. The homojunction hydrogels displayed 99 ± 0.25 % tetracycline degradation in 20 min in the photocatalytic-self-Fenton-PMS system. The experimental studies also claimed a maximum chemical oxygen demand removal of 81 ± 3.6 % in 20 min with maximum reusability of beads up to 20 cycles. The Z-scheme electron migration mechanism is proposed based on the results aided by scavenger and electron spin resonance analysis. Overall, the as-synthesized alginate-supported homojunction-based photocatalytic-self-Fenton-peroxymonosulfate system is highly versatile and reusable for energy and environmental remediation. [ABSTRACT FROM AUTHOR]

In this study, Z-type ZnIn 2 S 4 @CuO composites with a core–shell structure were synthesized. Under visible light irradiation, ZnIn 2 S 4 @CuO generates electron-hole pairs, and the presence of an internal electric field (IEF) improves the charge transfer mechanism of the composites and promotes the separation of charge carriers. The electrons on the conduction band of ZnIn 2 S 4 combine with dissolved oxygen in water to generate •O 2 –, and the holes on the valence band of CuO combine with OH– and H 2 O in water to generate •OH, and the generated reactive substances attack atoms on the TC to cause its ring-opening degradation, and ultimately mineralize the TC into CO 2 and H 2 O. [Display omitted] • A novel method for efficient construction of binary composites is proposed. • Z-type heterostructure reduces the photogenerated carrier complexation efficiency. • Verification of the Z-structure charge transfer mechanism. • TC degradation pathways proposed in combination with HR-MC and FEDs. In this study, copper oxide (CuO) was prepared by the microwave-assisted hydrothermal technique subsequently, CuO was grown in situ onto different rare metal compounds to prepare Z-scheme heterojunctions to improve the degradation efficiency of tetracycline (TC) in water environments. Various characterization proved the successful synthesis of all composite materials, and the formation of tight heterojunction interfaces, among which, the core–shell structure ZnIn 2 S 4 @CuO exhibited excellent photocatalytic degradation capability. Research results indicated that the degradation efficiency of ZnIn 2 S 4 @CuO for TC (50 mg/L) in the water environment reached 95.8 %, and the degradation rate is 2.41 times and 12.93 times that of CuO and ZnIn 2 S 4 alone, respectively, the reason is because of the introduction of ZnIn 2 S 4 , Z-scheme heterojunction structures and internal electric field (IEF) is constructed and formed to extend the visible light response range of photocatalysts to improve electron-hole separation efficiency, and enhance charge transfer. In addition, ZnIn 2 S 4 @CuO-2 exhibited good stability and reproducibility, with no significant loss of activity after five cycles. Finally, the precise locations of free radical attack on TC were investigated by the combined use of high-resolution mass spectrometry (HR-MC) and frontier electron densities (FEDs), and a reasonable degradation pathway was provided. The results of this research provide a new and viable approach to overcome the limitations of conventional photocatalytic materials in terms of limited visible light absorption range and fast carrier recombination rates, which offers promising prospects for a wide range of applications in the field of wastewater purification. [ABSTRACT FROM AUTHOR]

Novel NiAl 2 O 4 (NAO)/high entropy alloy (HEA) (Ti), NAO/HEA (Mn) and NAO/HEA (Mo) heterojunction photocatalysts with high photocatalytic activity for the degradation of tetracycline hydrochloride (TC) under simulated sunlight irradiation were synthesized by the polyacrylamide gel method combined with a low temperature sintering technique. The effects of environmental parameters, including drug concentration, catalyst content and pH value, on the photocatalytic activity of NAO/HEA photocatalysts were investigated in detail on the basis of the response surface methodology (RSM) and experimental results. The optimal initial TC concentration, catalyst content, and pH were 100 mg/L, 1 g/L, and 5, respectively. The photocatalytic activity of NAO/HEA photocatalyst (84.6 %) was significantly improved compared to the degradation percentage of HEA (Ti) photocatalyst (36.5 %). The roles of active free radicals including h+, •O 2 −, •OH and oxygen vacancy in photocatalysis were verified using multiple characterization methods. In-depth analysis was conducted on the degradation pathway of TC, the safety of degradation intermediates, and the photocatalytic mechanism of NAO/HEA (Ti) photocatalyst. The Z - scheme heterojunction can significantly improve the transport efficiency of photogenerated carriers and inhibit the recombination rate of electron hole pairs in the system, which provides a new idea for exploring the application of new HEA - based heterojunction photocatalysts in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

Using rapeseed straw as a raw material and potassium bicarbonate (KHCO3) and urea (CO(NH2)2) as modification reagents, the pyrolysis raw materials were mixed in a certain proportion, and the unmodified biochar GBC800, KHCO3-modified biochar KGBC800, and (KHCO3)/(CO(NH2)2) co-modified biochar N-KGBC800 were, respectively, prepared using the one-pot method at 800 °C. The physicochemical properties, such as surface morphology, pore characteristics, functional group distribution, and elemental composition of the three biochars, were characterized, and the adsorption performance and mechanism of the typical antibiotic tetracycline (TC) in water were studied. The results showed that the surface of GBC800 was smooth and dense, with no obvious pore structure, and both the specific surface area and total pore volume were small; the surface of KGBC800 showed an obvious coral-like three-dimensional carbon skeleton, the number of micropores and the specific surface area were significantly improved, and the degree of carbonization and aromatization was enhanced; N-KGBC800 had a coral-like three-dimensional carbon skeleton similar to KGBC800, and there were also many clustered carbon groups. The carbon layer changed significantly with interlayer gaps, presenting a multi-level porous structure. After N doping, the content of N increased, and new nitrogen-containing functional groups were formed. When the initial TC concentration was 100 mg/L, pH ≈ 3.4, the temperature was 25 °C, and the dosage of the three biochars was 0.15 g/L, the adsorption equilibrium was reached before 720 min. The adsorption capacities of GBC800, KGBC800, and N-KGBC800 for TC were 16.97 mg/g, 294.86 mg/g, and 604.71 mg/g, respectively. Fitting the kinetic model to the experimental data, the adsorption of TC by the three biochars was more in line with the pseudo-second-order adsorption kinetic model, and the adsorption isotherm was more in line with the Langmuir model. This adsorption process was a spontaneous endothermic reaction, mainly chemical adsorption, specifically involving multiple adsorption mechanisms such as pore filling, electrostatic attraction, hydrogen bonds, n−π interaction, Lewis acid–base interaction, π−π stacking, or cation −π interaction between the aromatic ring structure of the carbon itself and TC. A biochar-adsorption column was built to investigate the dynamic adsorption process of tetracycline using the three biochars against the background of laboratory pure water and salt water. The adsorption results show that the Thomas model and the Yoon–Nelson model both provide better predictions for dynamic adsorption processes. The modified biochars KGBC800 and N-KGBC800 can be used as preferred materials for the efficient adsorption of TC in water. [ABSTRACT FROM AUTHOR]

Fourth-degree calvarial burns are complex in management with regard to determining bone vitality and subsequent choice of defect coverage. Distinguishing viable and nonviable bone can be challenging. Tetracycline bone fluorescence is well described and in common use in maxillofacial patients with bisphosphonate osteonecrosis and has been reported in septic orthopedic surgery specifically periprosthetic joint infection. On the basis of viable bone fluoresces, the concept of polychrome fluorescence was extrapolated as a diagnostic tool for calvarial burns. Bone fluorescence presents an efficient, non-invasive, and cost-effective diagnostic tool delineating exact necrotic margins in fourth-degree burns ensuring targeted bone-sparing debridement. This report describes the use of polychrome bone fluorescence as an intraoperative tool including a single-center case report with fourth-degree calvarial burns. [ABSTRACT FROM AUTHOR]

In this study, magnetic granular activated carbon (MGAC) system based on persulfate (PS) for organic pollutant removal and its regeneration performance were comprehensively evaluated. Iron was successfully loaded onto the granular activated carbon (GAC) in the form of Fe3O4 through XRD patterns and SEM images. GAC and MGAC could activate PS for degrading tetracycline (TC). Compared with GAC, the adsorption and degradation of TC was significantly increased by 28% using MGAC. The optimized removal conditions were obtained: MGAC dosage of 1.5 g/L, PS concentration of 10 mM, and pH of 4.6. TC could be removed in a relatively wide pH from 3~9 using MGAC/PS system. The degradation mechanism was mainly ascribed to SO4•-, O2•-, and •OH radicals, according to the results of radical scavengers' studies. Moreover, MGAC had good recycling and reusability through peroxymonosulfate regeneration. Finally, a fixed bed reactor using MGAC was carried out to simulate practical application. This work not only provided insight into the antibiotics degradation using MGAC but also laid a foundation for the practical application of this composite. [ABSTRACT FROM AUTHOR]

Here, we present a retrospective study on honey bee brood diseases in the USA. The Bee Disease Diagnostic Laboratory (BDDL) in the USDA-ARS Beltsville Bee Research Laboratory received a total of 4790 brood samples between 2015 and 2022 from U.S. State Apiary Inspectors and beekeepers. Samples from 49 states were analyzed by microscopy for the presence and prevalence of two bacteria, Melissococcus plutonius and Paenibacillus larvae, causing European foulbrood (EFB) and American foulbrood (AFB) diseases, respectively. Samples that tested positive for AFB were cultured and subjected to antibiotic susceptibility tests via the agar disc diffusion method to determine their resistance to tetracycline (Terramycin®) and tylosin (Tylan®) antibiotics. A comprehensive data analysis was conducted at multiple levels, including state, month, year, nationwide, and climate region. Among the 49 states examined, EFB was identified in 44 states, while AFB was found in 31 states. Infection levels vary across states, ranging from 0% to 63.6% for EFB and from 0% to 54.8% for AFB. The national average of EFB (19.2%) was significantly (p < 0.001) higher than AFB (8.6%). Contrary to AFB, significant yearly increases (p < 0.001) were identified for EFB from 2015 to 2022. Furthermore, significant monthly variations were recorded for both brood diseases, with the highest occurrence of EFB observed from April to July. States with the lowest infection rates of both diseases were NV, ND, MS, AK, and AZ. The South U.S. climate region, which comprises six states, had the highest and lowest EFB and ABF infections, respectively. On a nationwide scale, the AFB resistance to tetracycline (38%) was significantly (p < 0.001) higher than the resistance to tylosin (27%). [ABSTRACT FROM AUTHOR]

Antibiotics are extensively employed in the treatment of human and animal ailments. However, their excessive use and poor biodegradability have led to a notable accumulation of antibiotics in the environment, presenting potential health hazards to humans. In this study, tetracycline (TC) was selected as a representative antibiotic, and a recyclable material, Mn-ZIF-67, was synthesized to degrade TC through adsorption and peroxidase-like activity. Mn-ZIF-67 significantly enhances the peroxidase-like activity of ZIF-67. The removal efficiency of TC was boosted by 300% compared to ZIF-67 within a 10-min timeframe. With its high catalytic activity and stability, Mn-ZIF-67 exhibits significant promise for the swift degradation and elimination of antibiotics from the environment. [ABSTRACT FROM AUTHOR]

ABSTRACT The BixOyIz and CoFe2O4 combination enhances photocatalytic degradation of tetracyclines (TCs). Three TC antibiotics including TC, oxytetracycline (OTC), and chlortetracycline (CTC) with high concentration (50 mg L−1) were utilized as target pollutant. Bi5O7I/Bi4O5I2, with its Z‐scheme, improves removal efficiency to 1.6 times that of Bi5O7I and 1.4 times that of Bi4O5I2. Ternary Bi5O7I/Bi4O5I2/CoFe2O4 (I/I/Co) composites further increase efficiency, with I/I/Co‐2 achieving 1.6 times that of I/I‐2. The improved performance is due to an optimized microstructure, which promotes light absorption and carrier transfer. CoFe2O4 nanoparticles on nanosheets create a double‐Z band structure, enhancing redox activity. Radical trapping experiments indicated the major active species (•O2−, OH−, and h+) in photocatalytic process of I/I/Co‐2. Based on their enhanced removal efficiencies for high‐concentration TCs, proper magnetic separation capacity, and recycling performance, the practical applications of I/I/Co composites to treat real TC wastewater might be implemented. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTY STATEMENTThe peel of Hylocereus undatus was employed in the preparation of biochar and firstly applied for tetracycline removal from aqueous solution. Based on different characterization techniques, the material was found to possess a variety of surface functional groups on a porous structure and a pH point of zero charge (pHpzc) of 9.3. Adsorption of tetracycline (TC) was conducted under varying conditions, revealing significant effects of carbonization temperature, solution pH, adsorbent dose, ionic strength, contact time and initial concentration of TC on the biochar adsorption capacity. Kinetic data on TC adsorption were best described using the Elovich kinetic model, with an initial adsorption rate of 167.3 mg g−1 min−1. Isotherm data on adsorption of the desired biochar showed the best fit with the Temkin isotherm model, followed by the Langmuir model, displaying maximum adsorption capacity at 12.4 mg g−1. The electrostatic interactions between the charged biochar surfaces and certain fractions of TC were proposed as the major mechanism, together with H-bonding, pore-filling effect and π–π interaction. This study demonstrates great potential of H. undatus peel as a starting material to prepare an effective and reusable adsorbent in the removal of TC.Literature is available on a large number of plant-based biochar adsorbents for the removal of antibiotics. However, to the best of our knowledge, no report has been published on applying biochar derived from Hylocereus undatus peel for antibiotics removal. This type of fruit peel is available in massive amounts in Vietnam and is considered as an agricultural solid waste. Therefore, to fill the gap in the literature and to converse this leftover waste into a value-added byproduct, we chose this study to prepare H. undatus peel-derived biochar for the elimination of TC in an aqueous solution. [ABSTRACT FROM AUTHOR]

Antibiotics with significant environmental toxicity, e.g., tetracyclines (TCs), are often used in large quantities worldwide, with 50–80% of the applied dose ending up in the environment. This study aimed to investigate the effects of exposure to tetracycline hydrochloride (TC) and minocycline hydrochloride (MIN) on L. minor. Our research evaluated the phytotoxicity of the TCs by analyzing plant growth and biomass and evaluating assimilation pigment levels and fluorescence. The research was extended with the ability potential of duckweed as a tool for removing TCs from water/wastewater. The results demonstrated that both TCs influenced Ir, Iy, biomass, and photosynthetic efficiency. The uptake of TC and MIN by duckweed was proportional to the concentration in the growth medium. The TC was absorbed more readily, reaching up to 8.09 mg × g−1 of dry weight (DW) at the highest concentration (19.2 mg × L−1), while MIN reached 6.01 mg × g−1 of DW. As indicated, the consequences of the influence of TC on plants were slightly smaller, in comparison to MIN, while the plants could biosorb this drug, even at the lowest tested concentration. This study has shown that using plants for drug biosorption can be an effective standalone or complementary method for water and wastewater treatment. [ABSTRACT FROM AUTHOR]

Tetracycline (TC) contamination in water is one of the key issues in global environmental protection, and traditional water treatment methods are difficult to remove antibiotic pollutants.Therefore, efficient and environmentally friendly treatment technologies are urgently needed. In this study, activated persulfate (PS) using a biochar-loaded nano zero-valent iron (BC-nZVI) advanced oxidation system was used to investigate the degradation effect, influencing factors, and mechanism of TC. BC-nZVI was prepared using the liquid-phase reduction method, and its structure and properties were analyzed by various characterization means. The results showed that nZVI was uniformly distributed on the surface or in the pores of BC, forming a stable complex. Degradation experiments showed that the BC-nZVI/PS system could degrade TC up to 99.57% under optimal conditions. The experiments under different conditions revealed that the iron-carbon ratio, dosing amount, PS concentration, and pH value all affected the degradation efficiency. Free radical burst and electron paramagnetic resonance (EPR) experiments confirmed the dominant roles of hydroxyl and sulfate radicals in the degradation process, and LC–MS experiments revealed the multi-step reaction process of TC degradation. This study provides a scientific basis for the efficient treatment of TC pollution in water. [ABSTRACT FROM AUTHOR]

Electro-Fenton (EF) technology has shown great potential in environmental remediation. However, developing efficient heterogeneous EF catalysts and understanding the relevant reaction mechanisms for pollutant degradation remain challenging. We propose a new system that combines aluminum–air battery electrocoagulation (EC) with EF. The system utilizes dual electron reduction of O2 to generate H2O2 in situ on the air cathodes of aluminum–air batteries and the formation of primary cells to produce electricity. Tetracycline (TC) is degraded by ·OH produced by the Fenton reaction. Under optimal conditions, the system exhibits excellent TC degradation efficiency and higher H2O2 production. The TC removal rate by the reaction system using a graphite cathode reached nearly 100% within 4 h, whereas the H2O2 yield reached 127.07 mg/L within 24 h. The experimental results show that the novel EF and EC composite system of aluminum–air batteries, through the electroflocculation mechanism and ·OH and EF reactions, with EC as the main factor, generates multiple •OH radicals that interact to efficiently remove TC. This work provides novel and important insights into EF technology, as well as new strategies for TC removal. [ABSTRACT FROM AUTHOR]

Background Growing evidence indicates antimicrobial resistance disproportionately affects individuals living in socially vulnerable areas. This study evaluated the association between the CDC/ATSDR Social Vulnerability Index (SVI) and Streptococcus pneumoniae (SP) antimicrobial resistance (AMR) in the United States. Methods Adult patients ≥18 years with 30-day nonduplicate SP isolates from ambulatory/hospital settings from January 2011 to December 2022 with zip codes of residence were evaluated across 177 facilities in the BD Insights Research Database. Isolates were identified as SP AMR if they were non-susceptible to ≥1 antibiotic class (macrolide, tetracycline, extended-spectrum cephalosporins, or penicillin). Associations between SP AMR and SVI score (overall and themes) were evaluated using generalized estimating equations with repeated measurements within county to account for within-cluster correlations. Results Of 8008 unique SP isolates from 574 US counties across 39 states, the overall proportion of AMR was 49.9%. A significant association between socioeconomic status (SES) theme and SP AMR was detected with higher SES theme SVI score (indicating greater social vulnerability) associated with greater risk of AMR. On average, a decile increase of SES, indicating greater vulnerability, was associated with a 1.28% increased risk of AMR (95% confidence interval [CI],.61%, 1.95%; P =.0002). A decile increase of household characteristic score was associated with a 0.81% increased risk in SP AMR (95% CI,.13%, 1.49%; P =.0197). There was no association between racial/ethnic minority status, housing type and transportation theme, or overall SVI score and SP AMR. Conclusions SES and household characteristics were the SVI themes most associated with SP AMR. [ABSTRACT FROM AUTHOR]

Constructing an S-scheme system with highly active catalysts is a significant approach for improving the separation of photoinduced carriers to solve the related environmental aggravation. In this study, a well-designed S-scheme AgVO3/CaIn2S4 photocatalyst was synthesized for water purification by in situ growing CaIn2S4 nanocrystals on AgVO3 nanorod surfaces. The optimized AgVO3/CaIn2S4 heterostructure demonstrates an enhanced photocatalytic efficiency (94.1%) toward tetracycline hydrochloride (TCH) degradation compared with bare AgVO3 (42.6%) and CaIn2S4 (81.6%). The significant enhancement of photocatalytic activity is attributed to the S-scheme charge transfer mechanism in the AgVO3/CaIn2S4 heterostructure, which effectively directs photogenerated charge migration, boosts charge transfer, and preserves the high redox capacity of photoexcited electrons and holes on different active sites. This study is expected to offer insights into strategically designing and preparing S-scheme heterojunction photocatalysts to improve water purification. [ABSTRACT FROM AUTHOR]

Objectives Methods Results Conclusions A 6‐week course of tetracycline eye ointment is an alternative to single ‐dose oral azithromycin in annual mass drug administration for trachoma control. Compliance with the recommended tetracycline eye ointment regimen has not been well characterised when administered as part of a trachoma control program.A routine mass drug administration for trachoma was carried out in 40 communities in the Amhara region of Ethiopia. Two tubes of tetracycline eye ointment, to be administered twice daily for 6 weeks, was offered to all children under 6 months of age, to pregnant women who declined to take azithromycin, and to all individuals with a macrolide allergy. Seven weeks following the mass drug administration, a treatment compliance survey was performed for all community members documented to have received tetracycline eye ointment during the mass drug administration.Of the 491 individuals documented as having received tetracycline eye ointment from the treatment records, 367 completed the survey, of which 214 recalled being offered tetracycline eye ointment. A total of 105 (49%) respondents reported taking ≥1 daily dose of tetracycline eye ointment on most days of the week for at least the first week. Only 20 (9%) respondents reported taking at least 1 tetracycline eye ointment dose per week for 6 weeks. The most common reasons for low compliance included ‘saving it for a future infection’ and ‘stopped because I (or my child) seemed healthy’. The odds of low compliance were greater for those who reported not having adequate counselling (e.g., odds ratio [OR] 5.3, 95% CI 2.5–28.9 when low compliance was defined as not taking a tetracycline eye ointment dose for most days of at least the first week).Compliance with tetracycline eye ointment was low when administered by a trachoma program during a routine mass drug administration, especially for those reporting inadequate counselling. Further research with a larger sample size and varied settings is warranted to better understand and improve compliance. [ABSTRACT FROM AUTHOR]

In this study, an adsorbent based on waste peanut husks was synthesized. To facilitate the easy removal and efficiency of these peanut husks, it was first endowed with magnetic properties via the coprecipitation method after which NH2-MIL-101 (Fe) was loaded onto the magnetized peanut husks. This magnetic biomass-MOF composite (MPN@NH2-MIL-101 (Fe)) was used for the removal of 2,4-dichlorophenoxyacetic acid (2,4-D) and tetracycline (TC) in single and binary systems. MPN@NH2-MIL-101 (Fe) was found to be a crystalline magnetic adsorbent with a mesoporous structure with a surface area of 70.5 m2 g−1, pH point of zero charge of about 4.05, and possesses oxygen and nitrogen atoms containing functional groups which promoted its interactions with the studied pollutants leading to their uptake. Owing to the nature of these contaminants, the interactions that occurred in these adsorption processes were found to be dominated by both chemisorption and physisorption mechanisms. The monolayer adsorption capacity of MPN@NH2-MIL-101 (Fe) towards 2,4-D and TC was found to be 79.2 ± 8.3 and 109 ± 3.76 mg g−1 according to the Langmuir model, respectively. In binary systems, MPN@NH2-MIL-101 (Fe) had a higher selectivity towards 2,4-D which could be due to its smaller size in comparison with TC signifying the role of intraparticle diffusion. These excellent features of MPN@NH2-MIL-101 (Fe) coupled with its stability in aqueous solution and ease associated with its removal may enhance its prospects as an alternative adsorbent for practical applications. [ABSTRACT FROM AUTHOR]

The new water-soluble di-anionic bi-sodium salt of tetracycline (TC), an antibiotic in clinical use, with the formula {[TC]2−[Na+(MeOH)(H2O)] [Na+]·(H2O)}n (TCNa) was synthesized. The compound was characterized by m.p., attenuated total reflectance-Fourier transform infra-red (ATR-FTIR) spectroscopy, and ultraviolet (UV) and proton nuclear magnetic resonance (1H NMR) spectroscopy in the solid state and in solution. The molecular weight (MW) was determined by cryoscopy. The crystal structure of TCNa was also determined by X-ray crystallography. The antibacterial activity of TCNa was evaluated against the bacterial species Pseudomonas aeruginosa (P. aeruginosa), Escherichia coli (E. coli), Staphylococcus epidermidis (S. epidermidis) and Staphylococcus aureus (S. aureus) by means of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and inhibition zones (IZs). Moreover, the ability of the compound to eradicate biofilm formation was also evaluated. The results are compared with those obtained for the commercially available drug TCH2. The in vitro and in vivo toxicities of TCNa were tested against human corneal epithelial cells (HCECs) and Artemia salina. [ABSTRACT FROM AUTHOR]

Tetracyclines (TCs) constitute a group of antibiotics that are commonly used to treat bacterial diseases, in veterinary medicine and as an additive in animal feed. This broad application has led to their accumulation in food products and the environment because sewage treatment plants cannot completely remove them. Therefore, the aim of this study was to synthesize graphene oxide (GO) and evaluate its TC adsorption properties in aqueous media. The effects of pH (between 2.5 and 11) and Ca2+ concentration (between 0 and 1 M) were thoroughly investigated. Structural, textural, and electrokinetic properties of the prepared GO were determined by N2 adsorption/desorption, XRD, TEM, UV–vis, FTIR, XPS, thermogravimetry and electrophoretic mobility measurements. TC adsorption on GO is an interplay between the two main roles played by Ca2+: competitor or bridging cation. At low pH, there is cation exchange, and Ca2+ behaves as a competitor of the positively charged TC species, decreasing adsorption as calcium concentration increases. At high, the formation of Ca bridges between the surface and TC (GO-Ca2+-TC) is favored, increasing the adsorption of the antibiotic by increasing calcium concentration. Different combinations of Ca2+ and pH effects are important to improve the use of GO either as a pH-dependent and reversible TC adsorbent for decontamination or as pH-independent adsorbent for TC quantification with electrochemical sensors. [ABSTRACT FROM AUTHOR]

Utilizing solar energy to decompose tetracycline (TC) is a green strategy to treat wastewater. Herein, a heterogeneous hollow structured TiO 2 decorated Pt nanoparticles were successfully designed and synthesized via hard-template approach and photo-deposition process toward TC photodegradation. The Pt nanoparticles loaded on the surface of hollow structured TiO 2 can increase the visible light absorption due to the local surface plasmon resonance (LSPR) effect. Furthermore, owing to the tough electron oscillation of the LSPR excitation, the plasmonic hot holes on the surface of Pt nanoparticles can capture the electrons of TiO 2 , effectively facilitating the separation of photo-excited charge carriers because of the formation of Schottky junction constructed between Pt and TiO 2. Combined the natural merits of shorten conveying path of charge carriers and physical structural stability for hollow structure, the optimal Pt/TiO 2 hetero-junction hybrid showed superior photocatalytic activity and durability for TC photodegradation with the degradation efficiency of 93.8 ​% after 30 ​min and the rate constant of 0.09196 min−1 under 300 ​W Xe lamp irradiation. This work displays a heterogeneous hybrids catalyst based on eco-friendly metal and semiconductor materials which can be used in the fields including without limitation TC photodegradation. [ABSTRACT FROM AUTHOR]