A Systematic Overview of Android Malware Detection

Due to the completely open-source nature of Android, the exploitable vulnerability of malware attacks is increasing. To stay ahead of other similar review work attempting to deal with the serious security problem of the Android environment, this work not only summarizes the approaches in the malware classification phase but also lays emphasis on the Android feature selection algorithm and presents some areas neglected in previous works in the field of Android malware detection, like limitations and commonly applied datasets in machine learning-based models. In this paper, the Android OS environment, feature selection, classification models, and confronted challenges of machine learning detection are described in detail. Based on the brief introduction to Android background knowledge, feature selection methods are elaborated from key perspectives as feature extraction, raw data preprocessing, valid feature subsets selection, and machine learning-based selection models. For the algorithms of the malware classification, machine learning methods are categorized according to different standards to present an all-around view. Furthermore, this paper focuses on the study of deterioration problems and evasion attacks in machine learning detectors

Two Laminaria japonica Fermentation Broths Alleviate Oxidative Stress and Inflammatory Response Caused by UVB Damage: Photoprotective and Reparative Effects

UVB radiation can induce oxidative stress and inflammatory response in human epidermal cells. We establish a UVB-induced damage model of human immortalized epidermal keratinocytes (HaCaT) to explore the protective and reparative effects of Laminaria japonica on UVB-damaged epidermal inflammation after fermentation by white Ganoderma lucidum (Curtis) P. Karst and Saccharomyces cerevisiae. Compared with unfermented Laminaria japonica, fermented Laminaria japonica possesses stronger in vitro free radical scavenging ability. Laminaria japonica white Ganoderma lucidum fermentation broth (LJ-G) and Laminaria japonica rice wine yeast fermentation broth (LJ-Y) can more effectively remove excess reactive oxygen species (ROS) in cells and increase the content of the intracellular antioxidant enzymes heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO-1). In addition, fermented Laminaria japonica effectively reduces the content of pro-inflammatory factors ILs, TNF-α and MMP-9 secreted by cells. The molecular research results show that fermented Laminaria japonica activates the Nrf2 signaling pathway, increases the synthesis of antioxidant enzymes, inhibits the gene expression levels of pro-inflammatory factors, and alleviates cellular oxidative stress and inflammatory response caused by UVB radiation. Based on the above results, we conclude that fermented Laminaria japonica has stronger antioxidant and anti-inflammatory activity than unfermented Laminaria japonica, possesses good safety, and can be developed and used as a functional inflammation reliever. Fermented Laminaria japonica polysaccharide has a more slender morphological structure and more rockulose, with better moisturizing and rheological properties

Inhibition of LPS-Induced Skin Inflammatory Response and Barrier Damage via MAPK/NF-κB Signaling Pathway by <i>Houttuynia cordata</i> Thunb Fermentation Broth

Houttuynia cordata Thunb is rich in active substances and has excellent antioxidant and anti-inflammatory activity. Scanning electron microscopy and gel permeation chromatography were used to analyze the molecular characteristics of the fermentation broth of Houttuynia cordata Thunb obtained through fermentation with Clavispora lusitaniae (HCT-f). The molecular weight of HCT-f was 2.64265 × 105 Da, and the polydispersity coefficient was 183.10, which were higher than that of unfermented broth of Houttuynia cordata Thunb (HCT). By investigating the active substance content and in vitro antioxidant activity of HCT-f and HCT, the results indicated that HCT-f had a higher active substance content and exhibited a superior scavenging effect on 2,2-diphenyl-1-picrylhydrazyl radicals and hydroxyl radicals, with IC50 values of 11.85% and 9.01%, respectively. Our results showed that HCT-f could effectively alleviate the increase in the secretion of inflammatory factors and apoptotic factors caused by lipopolysaccharide (LPS) stimulation, and had a certain effect on repairing skin barrier damage. HCT-f could exert an anti-inflammatory effect by down-regulating signaling in the MAPK/NF-κB pathway. The results of erythrocyte hemolysis and chicken embryo experiments showed that HCT-f had a high safety profile. Therefore, this study provides a theoretical basis for the application of HCT-f as an effective ingredient in food and cosmetics

Lactobacillus plantarum fermented Laminaria japonica alleviates UVB-induced epidermal photoinflammation via the Keap-1/Nrf2 pathway

UVB-induced human immortal keratinocyte (HaCaT) cell damage model was established to investigate the mitigating effect of Laminaria japonica Lactobacillus plantarum subsp. plantarum fermentation broth (LJf) on epidermal photoinflammation and barrier function impairment. Compared to unfermented Laminaria japonica (LJ), LJf contains higher levels of potent substances, as well as stronger in vitro antioxidant activity. LJf is able to scavenge excessive reactive oxygen species (ROS) and increase intracellular antioxidant enzyme content and synthesis levels. We also find that LJf is superior to LJ in inhibiting the release of ILs, TNF-α and MMP-9. LJf also increased the synthesis level of barrier function proteins and decreased the secretion level of Kallikrein-7 (KLK-7), effectively alleviating the level of inflammation, abnormal cell shedding, and impaired barrier function in the epidermis. LJf can inhibit the transcription levels of downstream regulators and inflammatory factors by activating the Nrf2 signaling pathway. Safety experiments reveal that LJf is non-irritating