The abuse and irrational use of tetracyclines (TCs) in human medicine and animal husbandry has become a serious concern, affecting the ecological environment and human health. The aim of this study was to develop a sensitive and selective method using fully automatic solid-phase extraction coupled with ultra-performance liquid chromatography-tandem mass spectrometry for the determination of twelve TCs in water. Four isotope-labeled internal standards for TCs were used to correct matrix effects. Several parameters affecting extraction efficiency were systematically optimized, and the optimum experimental conditions found were 1.0 L water sample with 0.5 g/L Na2EDTA (pH 3.0) extracted and enriched by CNW HLB cartridge and eluted by 4 mL of acetone:methanol (v/v, 1:1). The enrichment factors were up to 798-1059 but only requiring about 60 min per six samples. Under the optimized conditions, the linearity of the method ranged from 0.2 to 100 μg/L for 12 TCs, the detection limits were as low as 0.01-0.15 ng/L, and the recoveries were in the range of 70%-118%, with relative standard deviations less than 15%. The developed method can be successfully utilized for the determination of 12 TCs in pure water, tap water, river water, and mariculture seawater. In summary, three and six TCs were detected in river water and mariculture seawater, respectively, with total concentrations of 0.074-0.520 ng/L (mean 0.248 ng/L) and 0.792-58.369 ng/L (12.629 ng/L), respectively. Tetracycline (TC) and oxytetracycline (OTC) were the dominant TCs in river water, while doxytetracycline (DXC) and OTC were dominant in mariculture seawater.

Biochar, a sustainable sorbent derived from pyrolyzed biomass, has garnered attention for its efficacy in solid-phase extraction (SPE) of antibiotics, with a particular focus on tetracyclines (TCs). Despite its recognized potential, the intricate separation mechanisms operative in biochar-based SPE systems have not been fully deciphered. This investigation contrasts chlorella biochar against commercial bamboo biochar, harnessing an array of analytical methodologies-microstructure characterization, adsorption thermodynamics, competitive adsorption kinetics, H+ back titration, and selectivity adsorption studies-complemented by a Box-Behnken design for the optimization of chlorella/bamboo-SPE and subsequent application in the analysis of animal-derived foodstuffs. The study unveils that a hybrid sorbent, integrating nitrogen-doped microporous chlorella biochar with mesoporous bamboo biochar in a 95/5 mass ratio, markedly diminishes irreversible adsorption while enhancing selectivity, surpassing the performance of single biochar SPE systems. The elucidated separation mechanisms implicate a partition model, propelled by oxygen-rich functional groups on chlorella biochar and the rapid adsorption kinetics of bamboo biochar, all orchestrated by electrostatic interactions within the mixed biochar framework. Moreover, the synergy of mixed biochar-SPE with high-performance liquid chromatography (HPLC) demonstrates exceptional proficiency in detecting TCs in animal viscera, evidenced by recovery rates spanning 80.80 % to 106.98 % and RSDs ranging from 0.24 % to 14.69 %. In essence, this research not only sheds light on the multifaceted factors influencing SPE efficiency but also propels the use of biochar towards new horizons in environmental monitoring and food safety assurance.

Antibiotics are commonly released into paddy fields as mixtures via human activities. However, the simultaneous extraction and detection of these chemicals from multiple media are technically challenging due to their different physicochemical properties, resulting in unclear patterns of their transport in the soil-rice system. In this study, a \"quick, easy, cheap, effective, rugged, and safe\" (QuEChERS) method was developed for the simultaneous analysis of 4 tetracyclines (TCs) and 4 fluoroquinolones (FQs) in the soil and rice tissues from a local poultry farm, and thereby the distribution patterns of the target antibiotics in the soil-rice system and their risk levels to the soil were analyzed. After parameter optimization, the calibration range used for the target antibiotics was 0.1-50 μg/L and each calibration curve was linear with a coefficient of determination (R2 > 0.995); The QuEChERS method achieved satisfactory recovery rates (70.3-124.6%) along with sensitive detection limits (0.005-0.21 ng/g) for TCs and FQs in the soil, root, stem, leaf, and grain. Among the 8 antibiotics, enrofloxacin (ENX), ciprofloxacin (CIP), oxytetracycline (OTC), and doxycycline (DOX) were detected around a poultry farm. The four antibiotics in the collected paddy soils around the poultry farm ranged from 7.1 ng/g to 395.5 ng/g. Notably, ENX and DOX had higher ecological risks (risk quotient values >1) than CIP and OTC in soil. ENX, CIP, and DOX were highly enriched in rice roots with concentrations up to 471.9, 857.3, and 547.4 ng/g, respectively, which were also detected in rice aboveground tissues. The findings may provide both technical and practical guidance for the understanding of antibiotic environmental behavior and risks.

Legionella, one of the main pathogens that causes community-acquired pneumonia, can lead to Legionella pneumonia, a condition characterized predominantly by severe pneumonia. This disease, caused by the bacterium Legionella pneumophila, can quickly progress to critical pneumonia and is often associated with damage to multiple organs. As a result, it requires close attention in terms of clinical diagnosis and treatment. Omadacycline, a new type of tetracycline derivative belonging to the aminomethylcycline class of antibiotics, is a semi-synthetic compound derived from minocycline. Its key structural feature, the aminomethyl modification, allows omadacycline to overcome bacterial resistance and broadens its range of effectiveness against bacteria. Clinical studies have demonstrated that omadacycline is not metabolized in the body, and patients with hepatic and renal dysfunction do not need to adjust their dosage. This paper reports a case of successful treatment of Legionella pneumonia with omadacycline in a patient who initially did not respond to empirical treatment with moxifloxacin. The patient also experienced electrolyte disturbance, as well as dysfunction in the liver and kidneys, delirium, and other related psychiatric symptoms.

The escalating global consumption of tetracyclines (TCs) as broad-spectrum antibiotics necessitates innovative approaches to mitigate their pervasive environmental persistence and associated risks. While initiatives such as China\'s antimicrobial reduction efforts highlight the urgency of responsible TC usage, the need for efficient degradation methods remains paramount. Microbial degradation emerges as a promising solution, offering novel insights into degradation pathways and mechanisms. Despite challenges, including the optimization of microbial activity conditions and the risk of antibiotic resistance development, microbial degradation showcases significant innovation in its cost-effectiveness, environmental friendliness, and simplicity of implementation compared to traditional degradation methods. While the published reviews have summarized some aspects of biodegradation of TCs, a systematic and comprehensive summary of all the TC biodegradation pathways, reactions, intermediates, and final products including ring-opening products involved with enzymes and mechanisms of each bacterium and fungus reported is necessary. This review aims to fill the current gap in the literature by offering a thorough and systematic overview of the structure, bioactivity mechanism, detection methods, microbial degradation pathways, and molecular mechanisms of all tetracycline antibiotics in various microorganisms. It comprehensively collects and analyzes data on the microbial degradation pathways, including bacteria and fungi, intermediate and final products, ring-opening products, product toxicity, and the degradation mechanisms for all tetracyclines. Additionally, it points out future directions for the discovery of degradation-related genes/enzymes and microbial resources that can effectively degrade tetracyclines. This review is expected to contribute to advancing knowledge in this field and promoting the development of sustainable remediation strategies for contaminated environments.

The overuse and misuse of tetracycline (TCs) antibiotics, including tetracycline (TTC), oxytetracycline (OTC), doxycycline (DC), and chlortetracycline (CTC), pose a serious threat to human health. However, current rapid sensing platforms for tetracyclines can only quantify the total amount of TCs mixture, lacking real-time identification of individual components. To address this challenge, we integrated a deep learning strategy with fluorescence and colorimetry-based multi-mode logic gates in our self-designed smartphone-integrated toolbox for the real-time identification of natural TCs. Our ratiometric fluorescent probe (CD-Au NCs@ZIF-8) encapsulated carbon dots and Au NCs in ZIF-8 to prevent false negative or positive results. Additionally, our independently developed WeChat app enabled linear quantification of the four natural TCs using the fluorescence channels. The colorimetric channels were also utilized as outputs of logic gates to achieve real-time identification of the four individual natural tetracyclines. We anticipate this strategy could provide a new perspective for effective control of antibiotics.

Tetracyclines are widely used in Chinese apiculture. However, limited information is available on the presence of tetracycline residues in honey and the sources, degradation patterns, and associated health risks of these compounds. In this study, the presence of tetracyclines in honey samples across China was investigated over a four-year period. Additionally, the risks of dietary intake, as well as the sources and degradation patterns of tetracyclines in honey, were assessed. The three-dimensional spatial distributions (floral region, geographical region and entomological origin) of tetracyclines contamination varied significantly. Tetracycline residues in honey posed a moderate risk to children aged 3-10 years in Northwest China. Source analysis indicated that colony migration serves as the primary source of tetracyclines in honey. Based on the degradation patterns of tetracyclines in honey within colonies and during storage, oxytetracycline is more readily degraded than other tetracyclines. The main degradation products of tetracyclines are epimers and dehydration products, and the effects of these products on human health and the environment should be further evaluated in future studies. This comprehensive investigation provides valuable insights into the safe use and regulation of tetracyclines in Chinese apiculture.

UNASSIGNED: The study aims to obtain the real-world safety profile of tetracyclines in children younger than 8 years old and provide reference for clinical drug applications.
UNASSIGNED: We made a disproportionality analysis of the FDA Adverse Event Reporting System (FAERS) database through OpenVigil 2 and conducted a review of case reports regarding adverse drug reactions (ADRs) of tetracyclines in children younger than 8-year-old.
UNASSIGNED: FAERS analysis identified 32 ADRs of tetracyclines in children younger than 8-year-old. Respiratory, thoracic, and mediastinal disorders contained the most frequent ADRs among all system organ classes (SOCs). The top three positive signals with the highest proportional reporting ratio (PRR) were laryngeal injury, Horner\'s syndrome and methaemoglobinaemia. Sixteen published tetracyclines-associated cases in children younger than 8-year-old were identified in the literature, concentrating in three SOCs. Gastrointestinal disorders were the most commonly reported cases (n = 12).
UNASSIGNED: Several ADRs were newly reported only in children younger than 8-year-old in our research, including Horner\'s syndrome and methemoglobinemia. We recommended that the clinical practitioners should pay attention to the ADRs both in instruction and beyond the label. Take close care of children and timely intervene when the treatment is inevitable.

Novel metal-organic framework MIL-101(Cr)-NH2 functionalised hydrophilic polydopamine-modified Fe3O4 magnetic nanoparticles (Fe3O4@PDA@MIL-101(Cr)-NH2) were synthesised and used as magnetic solid-phase extraction (MSPE) adsorbents for extracting tetracyclines (TCs) from milk samples. The integrated Fe3O4@PDA@MIL-101(Cr)-NH2 exhibited convenient magnetic separation and exceptional multi-target binding capabilities. Furthermore, the PDA coating significantly enhanced the hydrophilicity and extraction efficiency of the material, thereby facilitating the extraction of trace TCs. Various factors affecting MSPE, such as adsorbent dosage, extraction time, pH value, and desorption conditions, were optimised. The developed MSPE method coupled with high-performance liquid chromatography demonstrated good linearity (R2 ≥ 0.9989), acceptable accuracy (82.2%-106.1%), good repeatability (intra-day precision of 0.8%-4.7% and inter-day precision of 1.1%-4.5%), low limits of detection (2.18-6.25 μg L-1), and low limits of quantification (6.54-18.75 μg L-1) in TCs detection. The approach was successfully used for the quantification of trace TCs in real milk samples.

Tetracycline antibiotics (TCs) are extensively used in clinical medicine, animal husbandry, and aquaculture because of their cost-effectiveness and high antibacterial efficacy. However, the presence of TCs residues in the environment poses risks to humans. In this study, an inner filter effect (IFE) fluorescent probe, 2,2\'-(ethane-1,2-diylbis((2-((2-methylquinolin-8-yl)amino)-2-oxoethyl)azanediyl))diacetic acid (MQDA), was developed for the rapid detection of Eu3+ within 30 s. And its complex [MQDA-Eu3+] was successfully used for the detection of TCs. Upon coordination of a carboxyl of MQDA with Eu3+ to form a [MQDA-Eu3+] complex, the carboxyl served as an antenna ligand for the effective detection of Eu3+ to intensify the emission intensity of MQDA via \"antenna effect\", the process was the energy absorbed by TCs via UV excitation was effectively transferred to Eu3+. Fluorescence quenching of the [MQDA-Eu3+] complex was caused by the IFE in multicolor fluorescence systems. The limits of detection of [MQDA-Eu3+] for oxytetracycline, chlorotetracycline hydrochloride, and tetracycline were 0.80, 0.93, and 1.7 μM in DMSO/HEPES (7:3, v/v, pH = 7.0), respectively. [MQDA-Eu3+] demonstrated sensitive detection of TCs in environmental and food samples with satisfactory recoveries and exhibited excellent imaging capabilities for TCs in living cells and zebrafish with low cytotoxicity. The proposed approach demonstrated considerable potential for the quantitative detection of TCs.