Marine biological injuries and their medical management: A narrative review

The marine environment can be extremely dangerous, and the harm caused by marine organisms when they contact the human body can be especially harmful, even deadly. Contact includes stings, bites, wounds, and consumption as food. In this article, the characteristics of the common marine biological injuries are summarized, the major marine organisms causing damage in China’s marine waters are described, and injury prevention and treatment methods are discussed.     

Structural insights into the specific interaction between Geobacillus stearothermophilus tryptophanyl-tRNA synthetase and antimicrobial Chuangxinmycin

The potential antimicrobial compound Chuangxinmycin (CXM) targets the tryptophanyl-tRNA synthetase (TrpRS) of both Gram-negative and Gram-positive bacteria. However, the specific steric recognition mode and interaction mechanism between CXM and TrpRS is unclear. Here, we studied this interaction using recombinant GsTrpRS from Geobacillus stearothermophilus by X-ray crystallography and molecular dynamics (MD) simulations. The crystal structure of the recombinant GsTrpRS in complex with CXM was experimentally determined to a resolution at 2.06 Å. After analysis using a complex-structure probe, MD simulations, and site-directed mutation verification through isothermal titration calorimetry, the interaction between CXM and GsTrpRS was determined to involve the key residues M129, D132, I133, and V141 of GsTrpRS. We further evaluated binding affinities between GsTrpRS WT/mutants and CXM; GsTrpRS was found to bind CXM through hydrogen bonds with D132 and hydrophobic interactions between the lipophilic tricyclic ring of CXM and M129, I133, and V141 in the substrate-binding pockets. This study elucidates the precise interaction mechanism between CXM and its target GsTrpRS at the molecular level and provides a theoretical foundation and guidance for the screening and rational design of more effective CXM analogs against both Gram-negative and Gram-positive bacteria.     

Reduced M2 macrophages and adventitia collagen dampen the structural integrity of blood blister–like aneurysms and induce preoperative rerupture

ObjectiveBlood blister–like aneurysms (BBAs) are extremely rare aneurysms. They are predisposed to preoperative rerupture with a high case‐fatality rate. Here, we attempt to interrogate the distinct clinicopathology and the histological basis underlying its clinical rerupture.MethodsThree middle meningeal arteries, 11 BBA (5 reruptured, 6 non‐rerupture) and 19 saccular aneurysm samples were obtained for histopathological investigation. Three reruptured BBAs, 3 non‐reruptured BBAs and 6 saccular (3 ruptured, 3 unruptured) aneurysms were obtained for quantitative flow cytometry analysis.ResultsCompared with true saccular aneurysms, the BBA aneurysm wall lacks arterial stroma cells including CD31+ endothelial cells and α‐SMA + smooth muscle cells. Only fibroblasts and adventitial collagen were observed in the BBA aneurysm wall. Meanwhile, BBAs were enriched with infiltrated inflammatory cells, especially polarized macrophages. Based on the rerupture status, those reruptured BBAs showed drastically reduced fibroblasts and adventitia collagen. Moreover, M2‐polarized macrophages were observed dominant in BBAs and exhibit repairing cellular functions based on their interplays with arterial fibroblasts. Reduced M2 macrophages and arterial tissue repairing modulation may be responsible for the decreasing collagen synthesis and fibrosis repairment, which potentially dampens the aneurysm integrity and induces BBA aneurysm reruputre.ConclusionsBBAs poses histopathological features of occult pseudoaneurysms or dissecting aneurysms. Reduced M2 macrophages and adventitia collagen may dampen the structural integrity of BBAs and induce preoperative rerupture.     

The anti-tumor effects of the combination of microwave hyperthermia and lobaplatin against breast cancer cells in vitro and in vivo

Background: Breast cancer is the main lethal disease among females. The combination of lobaplatin and microwave hyperthermia plays a crucial role in several kinds of cancer in the clinic, but its possible mechanism in breast cancer has remained indistinct.Methods: Mouse models were used to detect breast cancer progression. Cell growth was explored with MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphonyl)-2H-tetrazolium) and colony formation assays. Cell migration and invasion were investigated with a transwell assay. Cell apoptosis was probed with flow cytometry. The expression of apoptosis-associated proteins was examined with Western blots.Result: Combination treatment decreased breast cancer cell viability, colony formation, cell invasion and metastasis. In addition, the treatment-induced breast cancer cell apoptosis and autophagy, activated the c-Jun N-terminal kinase (JNK) signaling pathway, suppressed the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway, and down-regulated IAP and Bcl-2 family protein expression.Conclusion: These results indicate that lobaplatin is an effective breast cancer anti-tumor agent. Microwave hyperthermia was a useful adjunctive treatment. Combination treatment was more efficient than any single therapy. The possible mechanism for this effect was mainly associated with activation of the JNK signaling pathway, inactivation of the AKT/mTOR signaling pathway and down-regulation of the Bcl-2 and IAP families.