On the way to the azygos vein: a road of return rather than ruined

Abstract Background The malposition of central venous catheters (CVCs) may lead to vascular damage, perforation, and even mediastinal injury. The malposition of CVC from the right subclavian vein into the azygos vein is extremely rare. Here, we report a patient with CVC malposition into the azygos vein via the right subclavian vein. We conduct a comprehensive review of the anatomical structure of the azygos vein and the manifestations associated with azygos vein malposition. Additionally, we explore the resolution of repositioning the catheter into the superior vena cava by carefully withdrawing a specific length of the catheter. Case presentation A 79-year-old female presented to our department with symptoms of complete intestinal obstruction. A double-lumen CVC was inserted via the right subclavian vein to facilitate total parenteral nutrition. Due to the slow onset of sedative medications during surgery, the anesthetist erroneously believed that the CVC had penetrated the superior vena cava, leading to the premature removal of the CVC. Postoperative contrast-enhanced computed tomography of the chest confirmed that the central venous catheter had not penetrated the superior vena cava but malpositioned into the azygos vein. The patient was discharged 15 days after surgery without any complications. Conclusions CVC malposition into the azygos vein is extremely rare. Clinical practitioners should be vigilant regarding this form of catheter misplacement. Ensuring the accurate positioning of the CVC before each infusion is crucial. Utilizing chest X-rays in both frontal and lateral views, as well as chest computed tomography, can aid in confirming the presence of catheter misplacement

Development of PLGA-PEG-PLGA Hydrogel Delivery System for Enhanced Immunoreaction and Efficacy of Newcastle Disease Virus DNA Vaccine

The highly contagious Newcastle disease virus (NDV) continues to threaten poultry all over the world. The NDV DNA vaccine is a promising solution to the current Newcastle disease (ND) challenges, and thus an efficient delivery system should be developed to facilitate the efficacy of DNA vaccines. In this study, we developed a DNA vaccine delivery system consisting of a triblock copolymer of poly(lactide co-glycolide acid) and polyethylene glycol (PLGA-PEG-PLGA) hydrogel in which the recombinant NDV hemagglutinin-neuraminidase (HN) plasmid was encapsulated. Its characteristics, security, immune responses, and efficacy against highly virulent NDV were detected. The results showed that the plasmids were gradually released in a sustained manner from the hydrogel, which improved the biological stability of the plasmids and demonstrated a high biocompatibility. The plasmids, when they were incorporated into the hydrogel delivery system, enhanced immune activation and provided 100% protection against the highly virulent NDV strain. Furthermore, we proved that this NDV DNA hydrogel vaccine could improve the lymphocyte proliferation and increase the immunological cytokine production via the PI3K/Akt pathway. These results indicate that the PLGA-PEG-PLGA thermosensitive hydrogel could be a promising delivery system for the NDV DNA vaccine in order to achieve a sustained supply of plasmids and induce potent immune responses

Development and Validation of an Ultra-Performance Liquid Chromatography–Tandem Mass Spectrometry Method to Determine Maduramicin in Crayfish (<i>Procambarus clarkii</i>) and Evaluate Food Safety

Maduramicin (MAD) is widely introduced into aquatic environments and results in the contamination of fish products. Worryingly, the consumption of MAD-contaminated crayfish (Procambarus clarkii) may induce symptoms of Haff disease. In this study, to monitor this potential contamination and to understand the residue and elimination characteristics of MAD in edible tissues of crayfish, a sensitive and efficient ultra-performance liquid chromatography–tandem mass spectrometry method was developed, validated, and applied. After extraction with acetonitrile and purification by solid-phase extraction column, multiple-reaction monitoring mass spectrometry with positive ionization mode was used to determine MAD’s residues. The limits of detection and of quantification were 6 μg·kg−1 and 20 μg·kg−1, respectively. The fortified recoveries ranged from 74.2% to 110.4%, with relative standard deviation of 1.2% to 10.1%. Furthermore, MAD was completely eliminated after 3 and 5 days from abdominal muscle and hepatopancreas tissues of crayfish, respectively. The maximum residue limits (MRLs) of MAD respectively was 200 μg·kg−1 in muscle and 600 μg·kg−1 in the hepatopancreas, and its withdrawal time in both edible tissues was 25.8 °C·d. Collectively, the results of this study indicate the proposed method is an efficient tool to evaluate the public health risk associated with crayfish consumption

Maduramicin Inhibits Proliferation and Induces Apoptosis in Myoblast Cells

<div><p>Maduramicin, a polyether ionophore antibiotic derived from the bacterium <i>Actinomadura yumaensis</i>, is currently used as a feed additive against coccidiosis in poultry worldwide. It has been clinically observed that maduramicin can cause skeletal muscle and heart cell damage, resulting in skeletal muscle degeneration, heart failure, and even death in animals and humans, if improperly used. However, the mechanism of its toxic action in myoblasts is not well understood. Using mouse myoblasts (C2C12) and human rhabdomyosarcoma (RD and Rh30) cells as an experimental model for myoblasts, here we found that maduramicin inhibited cell proliferation and induced cell death in a concentration-dependent manner. Further studies revealed that maduramicin induced accumulation of the cells at G₀/G₁ phase of the cell cycle, and induced apoptosis in the cells. Concurrently, maduramicin downregulated protein expression of cyclin D1, cyclin-dependent kinases (CDK4 and CDK6), and CDC25A, and upregulated expression of the CDK inhibitors (p21^Cip1 and p27^Kip1), resulting in decreased phosphorylation of Rb. Maduramicin also induced expression of BAK, BAD, DR4, TRADD and TRAIL, leading to activation of caspases 8, 9 and 3 as well as cleavage of poly ADP ribose polymerase (PARP). Taken together, our results suggest that maduramicin executes its toxicity in myoblasts at least by inhibiting cell proliferation and inducing apoptotic cell death.</p></div

Synthesis of Tilmicosin Nanostructured Lipid Carriers for Improved Oral Delivery in Broilers: Physiochemical Characterization and Cellular Permeation

This study aimed to develop nanostructured lipid carriers (NLCs) for improved oral absorption of tilmicosin (TMS) in broilers. Thus, palmitic acid, lauric acid, and stearic acid were selected as solid lipids to formulate TMS-pNLCs, TMS-lNLCs, and TMS-sNLCs, respectively. They showed similar physicochemical properties and meanwhile possessed excellent storage and gastrointestinal stability. The TMS interacted with the lipid matrix and was encapsulated efficiently in NLCs in an amorphous structure. NLCs could enhance oral absorption of TMS compared to 10% tilmicosin phosphate solution in broilers, among which the TMS-sNLCs were the most efficient drug delivery carriers, with a relative oral bioavailability of 203.55%. NLCs could inhibit the efflux of P-glycoprotein (P-pg) toward TMS, which may be involved with improved oral absorption. Taken together, these types of solid lipids influenced the enhanced level of NLCs toward oral bioavailability of TMS, and the sNLCs proved to be the most promising oral delivery carriers of TMS

Maduramicin upregulates expression of DR4, TRADD, TRAIL, BAK and BAD, leading to activation of caspases 8, 9 and 3 as well as cleavage of PARP in C2C12 cells.

<p>C2C12 cells were treated with maduramicin for 24 h at indicated concentrations, followed by Western blotting with indicated antibodies. β-Tubulin was used for loading control. Representative blots are shown (A, C and E). Blots for indicated proteins were semi-quantified using NIH image J (B, D and F). Results are presented as means ± SE (n = 3, corresponding to three independent experiments). *<i>P</i><0.05, **<i>P</i><0.01, difference with the control group.</p

Maduramicin arrests C2C12 cells at G₀/G₁ phase of the cell cycle.

<p>C2C12 cells were treated with maduramicin for 24 h at indicated concentrations (A), or for indicated time at 0.5 µg/ml (B, C), followed by staining with PI and flow cytometry. (A, B) Results are presented as means ± SE (n = 3, corresponding to three independent experiments). *<i>P</i><0.05, **<i>P</i><0.01, difference with the control group. (C) Histograms from a representative experiment show the time-course effect of maduramicin on cell cycle profile in C2C12 cells. Note: Maduramicin increased sub-G₁ in a time-dependent manner.</p