Detection and characterization of microplastics in the human testis and semen.

The health risk of microplastics (MPs) is a growing global concern. Evidence of reproductive health damage caused by the accumulation of MPs in males is still lacking. In the present study, 6 testis and 30 semen samples were collected, and MPs were detected using both pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and laser direct infrared spectroscopy (LD-IR). The results showed that MPs were detected in both testis and semen, with an average abundance of 0.23 ± 0.45 particles/mL in semen and 11.60 ± 15.52 particles/g in testis. Microplastics in the testis were composed of polystyrene (PS) with 67.7 %, while polyethylene (PE) and polyvinyl chloride (PVC) were the predominant polymers in semen. Compared to fragments, fiber, and film detected in semen, the fragment was the main shape the in testis. The sizes of these microplastics ranged from 21.76 µm to 286.71 µm, and most (67 % and 80.6 %) were 20-100 µm in semen and testis. In summary, this study revealed for the first time that MPs pollute the human male reproductive system and that various MP characteristics appear in different regions, which provides critical information and basic data for the risk assessment of MPs to human health.

Novel casein antimicrobial peptides for the inhibition of oral pathogenic bacteria.

Milk casein is a rich source of antimicrobial peptides (AMPs) and the most common way to produce AMPs is enzymatic hydrolysis in vitro. In this study, active casein antimicrobial peptide (CAMPs) mixtures were generated by optimized proteolytic cleavage of milk casein. These natural-safe CAMPs mixtures exhibited high activity in the inhibition of Streptococcus mutans and Porphyromonas gingivalis. Morphological characterization suggested the pathogenic bacteria presented incomplete or irregular collapsed membrane surface after the treatment with active CAMPs mixtures. The CAMPs inhibition activity was also effective in the attachment and development of microbial biofilm. Potential CAMPs sequences were unambiguously determined by unbiased proteomic analysis and 301 potential CAMPs were obtained. The activity of 4 novel CAMPs was successfully confirmed by using synthetic standards. This study provides a promising milk CAMPs resource for the development of safe agents in oral bacteria inhibition and functional foods.

High-performance micro/nanoplastics characterization by MALDI-FTICR mass spectrometry.

Micro/nanoplastics (MNPs) are widespread environmental pollutants that cause high health risks. However, high heterogeneity in particle sizes and chemical compositions of MNPs make their accurate characterization extremely challenging. Herein, we established a matrix-assisted laser desorption ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) strategy for the unambiguous characterization of different types of MNPs with high performance, including polystyrene, polyethylene glycol terephthalate, polyamide, polymethyl methacrylate, acrylonitrile butadiene styrene copolymer, and polycarbonate. The MNP sample preparation and detection conditions were systematically optimized by using response surface methodology, and the MS detection signal-to-noise ratios were improved 1.5 times on average. The ultrahigh mass resolution of FTICR MS is crucial to the unambiguous elucidation of MNP structures. We demonstrate that this MS strategy is highly efficient in the characterization of polymer constitutions of environmental MNPs derived from foam, bottles, cable ties, and compact discs, providing a promising tool for MNP detection and safety evaluation.

Posterior wedge osteotomy assisted by O-arm navigation for treating ankylosing spondylitis with thoracolumbar fractures: an early clinical evaluation.

BACKGROUND: To explore the feasibility and efficiency of posterior wedge osteotomy assisted by O-arm navigation treatment of ankylosing spondylitis (AS) patients with thoracolumbar fracture. METHODS: This is a case series study. A total of 16 cases of AS accompanied by thoracolumbar fractures from January 2012 to July 2015 were retrospectively analyzed. All patients underwent "posterior wedge osteotomy assisted by O-arm navigation". The operation time, blood loss volume, preoperative and postoperative visual analogue scale (VAS), American Spinal Injury Association (ASIA) classification, and spinal imaging parameters [Cobb angle, C7 plumb line (C7PL), and jaw-brow angle] were collected and analyzed. RESULTS: The operative time consumption was 120-350 mins and the intra-operative blood loss volume was 200-800 mL. No obvious postoperative complications occurred in any participants. The back pain of all participants was relieved, and the neurological functions of eight participants with spinal cord injury (SCI) were recovered in varying degrees except for one patient with severe SCI. The spinal deformities of the participants were corrected to varying degrees. The fracture sites of 16 participants were all healed, and there was no loosening or detachment of internal fixation during the 6-month follow-up period. CONCLUSIONS: Posterior wedge osteotomy assisted by O-arm navigation was shown to be a safe and effective method to treat AS accompanied by thoracolumbar fractures. This treatment strategy can accurately decompress and reduce the fracture and significantly correct the kyphosis, with good surgical effect.