Isolation and Identification of Four Strains of Bacteria with Potential to Biodegrade Polyethylene and Polypropylene from Mangrove.

With the rapid growth of global plastic production, the degradation of microplastics (MPs) has received widespread attention, and the search for efficient biodegradation pathways has become a hot topic. The aim of this study was to screen mangrove sediment and surface water for bacteria capable of degrading polyethylene (PE) and polypropylene (PP) MPs. In this study, two strains of PE-degrading bacteria and two strains of PP-degrading candidate bacteria were obtained from mangrove, named Pseudomonas sp. strain GIA7, Bacillus cereus strain GIA17, Acinetobacter sp. strain GIB8, and Bacillus cereus strain GIB10. The results showed that the degradation rate of the bacteria increased gradually with the increase in degradation time for 60 days. Most of the MP-degrading bacteria had higher degradation rates in the presence of weak acid. The appropriate addition of Mg2+ and K+ was favorable to improve the degradation rate of MPs. Interestingly, high salt concentration inhibited the biodegradation of MPs. Results of scanning electron microscopy (SEM), atomic force microscopy (AFM), and Fourier-transform infrared spectroscopy (FTIR) indicated the degradation and surface changes of PP and PE MPs caused by candidate bacteria, which may depend on the biodegradation-related enzymes laccase and lipase. Our results indicated that these four bacterial strains may contribute to the biodegradation of MPs in the mangrove environment.

Clinical efficacy of Femoral Neck System for treatment of unstable femoral neck fractures in young adults.

OBJECTIVE: This study was performed to evaluate the mid-term clinical efficacy of the Femoral Neck System (FNS) (DePuy Synthes, Zuchwil, Switzerland) in treating young patients with unstable Pauwels type III femoral neck fractures. METHODS: We performed a retrospective observational analysis of 21 young adults treated with the FNS. Clinical outcomes were assessed based on fracture reduction quality, Harris hip scores, and postoperative complication rates. RESULTS: The study comprised 21 patients with a mean age of 35 years (range, 20-50 years) who were followed for a mean duration of 22.8 months (range, 16-30 months). Closed reduction was unfeasible in three (14.3%) patients, each of whom required open reduction. Notable postoperative complications were avascular necrosis in two (9.5%) patients, nonunion in one (4.7%), and implant failure in one (4.7%). Each of these complications led to the requirement for total hip arthroplasty. CONCLUSION: The favorable mid-term clinical outcomes of this study indicate that the FNS is a potentially effective treatment modality for young individuals with unstable Pauwels type III femoral neck fractures.

Mangrove plants are promising bioindicator of coastal atmospheric microplastics pollution.

Plastics are commonly used by society and their break down into millimeter-sized bits known as microplastics (MPs). Due to the possibility of exposure, reports of them in atmospheric deposition, indoor, and outdoor air have sparked worry for public health. In tropical and subtropical regions all throughout the world, mangroves constitute a distinctive and significant type of coastal wetlands. Mangrove plants are considered to have the effect of accumulating sediment MPs, but the sedimentation of atmospheric MPs has not been reported. In this study, we illustrated the characteristics, abundance and spatial distribution of MPs in different species of mangrove leaves along the Seagull Island in Guangzhou. MPs samples from leaves in five species showed various shapes, colors, compositions, sizes and abundance. Acanthus ilicifolius had an average fallout rate of 1223 items/m2/day which has the highest abundance of MPs in all samples. Four shapes of MPs were found in all leaves surfaces including fiber, fragment, pellet, and film, with fiber is the most. The dominant types of MPs in all leaves were cellulose and rayon. Most of the total MPs size were smaller than 2 mm. Clearly, the microstructures of each species leaf surfaces had an impact on its ability to retain MPs. The plants rough blade surfaces and big folds or gullies caused more particles to accumulate and had a higher MPs retention capacity. Overall, our study contributes to a better knowledge of the condition of MPs pollution in atmosphere and the connection between leaves structure and the retention of MPs, which indicates that mangrove plants are promising bioindicator of coastal atmospheric MPs pollution.

Combined effects of microplastics and antibiotic-resistant bacteria on Daphnia magna growth and expression of functional genes.

Microplastics could act as vectors for the transport of harmful bacteria, such as pathogens and antibiotic resistance bacteria (ARB), but their combined effects have not been reported yet. Here, ARB Shigella flexneri with sulfonamides resistance and micro-polystyrene (micro-PS) were used to investigate their possible combined effects on the growth and expression of functional genes in Daphnia magna. Results showed that micro-PS colonized with S. flexneri were ingested by D. magna and blocked in their intestine after 24 h exposure. Changes were observed in the life history and morphology of D. magna, as well as the expression of functional genes in all treatments, but with no difference in the survival rate. We also determined the expression of six functional genes involved in energy and metabolism (arginine kinase, AK) and oxidative stress response (thioredoxin reductase, TRxR, catalase, CAT, and glutathione S-transferases, GSTs), as well as in growth, development and reproduction (vitellogenin, Vtg1 and ecdysone receptor, EcR). AK and Vtg1 did not show significant differences, however, EcR was down-regulated and the other three genes (TRxR, CAT, GSTs) were up-regulated in the combined-treated group. Antibiotic resistance gene (ARGs) sul1 was detected when exposed to micro-PS colonized with S. flexneri., suggesting that D. magna could acquire resistance genes through microplastic biofilms. These results indicated that MPs could act as a carrier of ARB to transfer ARGs into D. magna, and affect the life history, morphology, and the expression of related functional genes of D. magna, to adapt to the stress caused by MPs and ARB.

Biological Degradation of Plastics and Microplastics: A Recent Perspective on Associated Mechanisms and Influencing Factors.

Plastic and microplastic pollution has caused a great deal of ecological problems because of its persistence and potential adverse effects on human health. The degradation of plastics through biological processes is of great significance for ecological health, therefore, the feasibility of plastic degradation by microorganisms has attracted a lot of attention. This study comprises a preliminary discussion on the biodegradation mechanism and the advantages and roles of different bacterial enzymes, such as PET hydrolase and PCL-cutinase, in the degradation of different polymers, such as PET and PCL, respectively. With a particular focus on their modes of action and potential enzymatic mechanisms, this review sums up studies on the biological degradation of plastics and microplastics related to mechanisms and influencing factors, along with their enzymes in enhancing the degradation of synthetic plastics in the process. In addition, biodegradation of plastic is also affected by plastic additives and plasticizers. Plasticizers and additives in the composition of plastics can cause harmful impacts. To further improve the degradation efficiency of polymers, various pretreatments to improve the efficiency of biodegradation, which can cause a significant reduction in toxic plastic pollution, were also preliminarily discussed here. The existing research and data show a large number of microorganisms involved in plastic biodegradation, though their specific mechanisms have not been thoroughly explored yet. Therefore, there is a significant potential for employing various bacterial strains for efficient degradation of plastics to improve human health and safety.

Characteristics of microplastic pollution and analysis of colonized-microbiota in a freshwater aquaculture system.

The microbial communities associated with microplastics (MPs) and their ambient environments have received wide attention. Although previous studies have reported the differences of microbial communities between MPs and natural environment or substrates, the effects of MPs on microbial balance and functions in ambient water remain unclear, particularly for aquaculture water. Here, we investigated the MPs pollution in farm ponds of grass carp located in the Foshan City of Guangdong Province and reported the distinction of bacterial structures, functions, and complexity between microbiota on MPs and in water. MPs with an average abundance of 288.53 ± 74.27 items/L in pond water were mostly fibers and cellulose, mainly transparent and in size of 0.5-1 mm. Structures and functions of bacterial communities on MPs significantly differed from that in pond water. A large number of enriched or depleted OTUs on MPs compared with water belong to the phylum Proteobacteria, the predominant phylum in microbial communities on MPs and in water. Some species included in the phylum Proteobacteria have been shown to be cellulose-degrading and pathogenic. Microbiota on MPs exhibited higher species richness and diversity as well as a more complex network than that in water, illustrating MPs as a distinct habitat in the aquaculture system.

Microplastics as an aquatic pollutant affect gut microbiota within aquatic animals.

The adverse impact of microplastics (MPs) on gut microbiota within aquatic animals depends on the overall effect of chemicals and biofilm of MPs. Thus, it is ideal to fully understand the influences that arise from each or even all of these characteristics, which should give us a whole picture of consequences that are brought by MPs. Harmful effects of MPs on gut microbiota within aquatic organisms start from the ingestion of MPs by aquatic organisms. According to this, the present review will discuss the ingestion of MPs and its following results on gut microbial communities within aquatic animals, in which chemical components, such as plastic polymers, heavy metals and POPs, and the biofilm of MPs would be involved. This review firstly analyzed the impacts of MPs on aquatic organisms in detail about its chemical components and biofilm based on previous relevant studies. At last, the significance of field studies, functional studies and complex dynamics of gut microbial ecology in the future research of MPs affecting gut microbiota is discussed.

Regulation of SOX10 stability via ubiquitination-mediated degradation by Fbxw7α modulates melanoma cell migration.

Dysregulation of SOX10 was reported to be correlated with the progression of multiple cancer types, including melanocytic tumors and tumors of the nervous system. However, the mechanisms by which SOX10 is dysregulated in these tumors are poorly understood. In this study, we report that SOX10 is a direct substrate of Fbxw7α E3 ubiquitin ligase, a tumor suppressor in multiple cancers. Fbxw7α promotes SOX10 ubiquitination-mediated turnover through CPD domain of SOX10. Besides, GSK3ß phosphorylates SOX10 at CPD domain and facilitates Fbxw7α-mediated SOX10 degradation. Moreover, SOX10 protein levels were inversely correlated with Fbxw7α in melanoma cells, and modulation of Fbxw7α levels regulated the expression of SOX10 and its downstream gene MIA. More importantly, SOX10 reversed Fbxw7α-mediated suppression of melanoma cell migration. This study provides evidence that the tumor suppressor Fbxw7α is the E3 ubiquitin ligase responsible for the degradation of SOX10, and suggests that reduced Fbxw7α might contribute to the upregulation of SOX10 in melanoma cells.

Early stage alopecia areata is associated with inflammation in the upper dermis and damage to the hair follicle infundibulum.

BACKGROUND/OBJECTIVES: Alopecia areata (AA) is a non-scarring inflammatory hair loss disease. We investigated the early pathological changes of AA to identify possible factors participating in its pathogenesis. METHODS: Clinical, laboratory and pathological features of 87 AA patients were investigated. RESULTS: Anti-nuclear antibody was found in 11 of 85 patients tested (13%), with a higher percentage in women (21%) than men (5%) (P = 0.026). In early AA lesions, inflammatory infiltration in the upper dermis and epithelial cell damage of the hair follicle infundibulum, just above the sebaceous gland, was observed. Liquefaction and disarrangement of peripheral infundibular epithelial cells coexisted with T-lymphocytic invasion and regression of the lower follicle. The latter findings positively correlated with the presence of eosinophils and perivascular mononuclear cell infiltration in the upper dermis. Eosinophilic infiltration was found in 35 patients (40%) and was positively correlated to elevated serum IgE levels (r = 0.21, P = 0.044), a more severe perivascular lymphocytic inflammation in the upper dermis (r = 0.24, P = 0.026), as well as a prominent swarm of bees-like peri-follicular infiltration (r = 0.41, P < 0.001). Mast cells were abundant in the upper dermis, especially around blood vessels, and positively correlated with eosinophil presence (r = 0.30, P = 0.027). CONCLUSION: Damage to the hair follicle infundibulum in the upper dermis might be an important component of early changes in AA lesions, possibly caused by lymphocyte cell infiltration in the same area. AA may involve damage of the upper hair follicle as well as the bulb, possibly involving hypersensitivity and autoimmunity.

Female pattern hair loss: clinico-laboratory findings and trichoscopy depending on disease severity.

BACKGROUND: Female pattern hair loss (FPHL) is a progressive hair loss disorder with unclear triggering and supporting factors. Trichoscopic features of each stage of FPHL have not been specifically elaborated previously. AIMS: To analyze characteristics and investigate associations of clinico-laboratory and trichoscopic features of female patients in regard to the severity of hair loss in FPHL and to facilitate its diagnosis using noninvasive scalp dermoscopy (trichoscopy) in Fitzpatrick skin type III patients. MATERIALS AND METHODS: Clinico-laboratory and trichoscopic data from 60 patients with FPHL were analyzed using Spearman's correlation test. RESULTS: Patients had mean age of 34.4±10.6 years and mean duration of hair loss of 4.49±3.76 years. Of all, 45% (27/60) had a family history of pattern hair loss (PHL) and had an earlier onset of hair loss. Stage of hair loss positively correlated with duration and age at presentation. No association was found between the severity of FPHL and laboratory values including anemic and gonadal hormone profiles. Characteristic trichoscopic features (at 10-fold magnification) of FPHL were peripilar signs (PPS) (brown, BPPS and white, WPPS), white dots, scalp pigmentation, and focal atrichia. WPPS, scalp pigmentation, and focal atrichia positively correlated with the stage and duration of hair loss. CONCLUSIONS: Family history of PHL causes an earlier onset of hair loss but does not influence its course or severity. The latter is also not affected by abnormal anemic profile or hormonal levels. PPS, scalp pigmentation, focal atrichia, and white dots are characteristic of PHL. WPPS, scalp pigmentation, and focal atrichia reflect advanced PHL.