Sulfapyridine 250mg capsules

Sulfasalazine has been identified as a candidate molecule to be investigated as an intervention to treat preterm pre-eclampsia during pregnancy. However, placental exposure of sulfasalazine and its systemically absorbed metabolite, sulfapyridine, is unknown. A robust liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to simultaneously quantitate these analytes in human placenta with an application to a pilot clinical trial. The placental tissue was homogenised using a water:methanol (1:1, v/v) mixture, followed by sample extraction using both protein precipitation and solid phase extraction. Sulfasalazine-d4 and sulfapyridine-d4 were used as internal standards. An Agilent Poroshell EC-C18 (3.0 ×100 mm, 2.7 µm) column was used for chromatographic separation, with gradient elution employed at a flow rate of 0.450 mL/min over a total run time of seven minutes. The mobile phases consisted of water with 0.1% formic acid (mobile phase A) and acetonitrile:methanol (90:10, v/v) with 0.1% formic acid (mobile phase B). A Shimadzu-8040 mass spectrometer was operated in multiple reaction monitoring (MRM) mode using positive electrospray ionisation (ESI). For both analytes, the assay was validated over the range 30-30,000 ng/mL, or 150-150,000 ng/g. During inter-day validations (n = 18), the average accuracies of quality controls ranged from 101.6% to 112.7% with corresponding precisions of 4.4-6.7% for sulfasalazine, and from 97.4% to 108.4%, with corresponding precisions of 3.7-10.0% for sulfapyridine. No significant matrix effects were observed, and the method proved to be sensitive and specific for both analytes. This study presents the first validated analytical method for quantifying sulfasalazine and sulfapyridine in human placenta as part of a pilot clinical trial to generate preliminary data on its pharmacokinetics and efficacy as in intervention for preterm pre-eclampsia.

Abstract licence: CC BY

Abstract Pharmaceutical antibiotics are frequently used in the livestock and poultry industries to control infectious diseases. Due to the lack of proper guidance for use, the majority of administrated antibiotics and their metabolites are excreted to the soil environment through urine and feces. In the present study, we used chlortetracycline and sulfapyridine antibiotics to screen out their effects on dehydrogenase, alkaline phosphatase and urease activity. Factorial experiments were conducted with different concentrations of antibiotic (0, 10, 25 and 100 mg kg −1 of soil) mixed with soil samples, and the enzyme activity was measured at intervals of 1, 4 and 21 days. The results show that the chlortetracycline and sulfapyridine antibiotics negatively affect the dehydrogenase activity, but the effect of sulfapyridine decreases with time of incubation. Indeed, sulfapyridine antibiotic significantly affect the alkaline phosphatase activity for the entire three-time interval, while chlortetracycline seems to inhibit its activity within 1 and 4 days of incubation. The effects of chlortetracycline and sulfapyridine antibiotics on urease activity appear similar, as they both significantly affect the urease activity on day 1 of incubation. The present study concludes that chlortetracycline and sulfapyridine antibiotics have harmful effects on soil microbes, with the extent of effects varying with the duration of incubation and the type of antibiotics used.

Abstract licence: CC BY

Monitoring antimicrobial resistance genes (ARGs) in wastewater influents (pre-treatment) and effluents (post-treatment) provides insights into community-level circulation, potential amplification during treatment, and risks associated with gene release into surface waters. Pollutants such as antibiotic residues and microplastics (MPs) may influence ARG dynamics, highlighting the need to assess their dynamics across wastewater environments. In this study, we analyzed ARGs and bacterial communities using Oxford Nanopore (ONP) metagenomics and qPCR in wastewater samples from Mekjarvik (Norway), Reykjavik (Iceland), and Mariehamn (Åland, Finland). Antibiotic residues were quantified via High-Performance Liquid Chromatography (HPLC), and MPs were characterized using Micro-Fourier Transform Infrared Spectroscopy (μ-FTIR) in Mekjarvik and Reykjavik. Metagenomic analysis identified 193 unique ARGs, with the highest average (±SD) in Reykjavik (66.3 ± 4.1), followed by Mekjarvik (61.3 ± 14.1) and Mariehamn (18.0 ± 2.2). ONP sequencing revealed that many ARGs were plasmid-associated, co-occurring with metal stress genes. Common plasmids were Col440I , IncQ2 , and ColRNAI . Mercury-related genes dominated metal stress genes (64.9%), followed by multimetal (23.7%) and copper (6.4%). Of 45 antibiotics screened, only sulfamethoxazole and sulfapyridine were consistently detected. Polyethylene (∼60%) was the dominant MP type; Reykjavik influent had the highest MP load (8200 MPs/m 3 ). While treatment reduced ARGs, antibiotic residues, and larger MPs, it was less effective against fine particles and key ARGs, including carbapenemase- and ESBL-associated genes. Clinically relevant ARGs and potential pathogens (e.g., Acinetobacter baumannii , Pseudomonas aeruginosa ) persisted in effluents, highlighting risks to downstream ecosystems. These findings underscore the need for regular monitoring of both influents and effluents to assess treatment performance and safeguard environmental health. • Wastewater influent and effluent from Norway, Iceland, and Finland were analyzed • ARG dynamics varied across treatment plants and did not align with antibiotic residue detection • Only sulfamethoxazole and sulfapyridine were consistently detected • Treatment removed larger microplastics but was less efficient for smaller ones

Abstract licence: CC BY

The evolution of teleost coloration is strongly linked with the fish-specific genome duplication (FSGD). Sepiapterin reductase (Spr) is commonly required in pteridine pigment synthesis and two paralogs are found in teleosts. However, the functions of spra and sprb in pigmentation have not been completely elucidated. Here we found that spra was intensively expressed in skin, fins and scales of koi carp, while sprb was ubiquitously expressed in all tissues. Then, the Spr enzyme activity inhibitor, sulfapyridine (SFD), was used to explore the phenotype and genes variation after spr inhibition. Following the administration of SFD, spra was significantly suppressed but sprb was up-regulated in skin. Additionally, the color phenotypes shifted from red to yellow due to a reduction in carotenoid concentration and the number of xanthophores/erythrophores in scales. Furthermore, the genes involved in carotenoid metabolism were influenced. However, pteridine metabolism-related genes rarely exhibited obvious changes. The results indicate that spra inhibition resulted in the dysregulation of carotenoid metabolism and pigment cells reduction, whereas sprb was likely to maintain the conserved functions in pteridine synthesis for metabolic homoeostasis. This study provided evidences for the different functions of spr paralogs in carotenoid and pteridine metabolism and for better understanding of the relationship between genome duplication and color pattern diversification.

Abstract licence: CC BY-NC-ND

Conventional wastewater treatment processes struggle to effectively degrade antibiotics due to their low concentration, high toxicity and poor degradability. Significant concentration of antibiotic drugs and intermediates persist in discharged effluent, posing serious threats to human health and aquatic ecosystem safety. Manganese-based activated carbon (MnOx-GAC) and molecular imprinting (MIP) were synthesized in 70°C to form MnOx-GAC/MIP at 2 mmol methacrylic acid, 3.35 mmol sulfapyridine(SPY) and 10 mmol EDGMA, promoting selectively recognize and target catalytic degradation of SPY. Compared with non-targeted catalysts, the targeted catalytic ability of the MnOx-GAC/MIP by the hydrothermal method for SPY was enhanced by 2.7 times at 0.24 g/L MnOx-GAC/MIP, 6 mg/L PDS and initial pH 3. In the MnOx-GAC/MIP-PDS system, the SPY degradation mainly proceeds via the chemical bond breakage, followed by its methylation. The second-order rates of • OH (4.75×10 10 M -1 s -1 ) and SO 4 •- (1.30×10 10 M -1 s -1 ) reacting with SPY clarified • OH reacted with SPY faster than SO 4 •- . The proposal of targeted degradation methods would facilitate the efficient degradation of trace antibiotics.

Abstract licence: CC BY-NC-ND