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Lower respiratory infection (LRI) is the most fatal communicable disease, with only a few pathogens identified. Metagenomic next-generation sequencing (mNGS), as an unbiased, hypothesis-free, and culture-independent method, theoretically enables the detection of all pathogens in a single test. In this study, we developed and validated a DNA-based mNGS method for the diagnosis of LRIs from bronchoalveolar lavage fluid (BALF). We prepared simulated

Human hair fibers are structurally organized as a cortex protected by an outer scaly sheath (cuticle). Developing methods to isolate these two compartments will help to elucidate their roles in hair biology and develop potential applications. Herein, we developed enzymatic methods for human hair cuticle cell harvesting or removal. After a single treatment with esperase for three days, cuticle cells were released from hair shafts and effectively harvested by a series of filtration, centrifugation and resuspension steps. Separately, combining L-cysteine and either esperase or savinase could remove the entire cuticle layer to obtain descaled hair fibers. The physical and chemical structures, and performance of the isolated cuticle cells and descaled hair samples were characterized using electron microscopy, FTIR, solid state 13C NMR, TGA and DSC. Results show that the harvested cuticle cells contain mainly β-sheets and random coil structures, while descaled hair samples contain more α-helical structures. Harvested cuticle cells have greater thermal stability than the descaled hair samples below 260 C. The enzymatic methods developed in this study are convenient and easily controlled. They are effective not just for cuticle cell harvesting but also for surface modification and structure disintegration of hair fibers. Agency for Science, Technology and Research (A*STAR) Accepted version This research was supported by the Agency for Science, Technology and Research (A*STAR) under its Acne and Sebaceous Gland Program & Wound Care Innovation for the Tropics IAF-PP (H17/01/a0/008 & H17/01/a0/0L9), the China Scholarship Council (Grant No. 201906790039 to N.Z.), and the National Natural Science Foundation of China (51673087).

The selected-dissolution behaviour of metals after the film rupture determines the propagation of localized corrosion. Meanwhile, excessive Cl− aggregations and too fast resorption behaviour may prematurely lead to the loss of mechanical properties. In this study, the degradation behaviour and mechanical properties of the heat-treated Mg-2Zn-0.2Mn-xNd (MZM-xNd) in the simulated body fluid were analyzed using XRD, XPS, FT-IR, TEM, 3D/CLSM and AFM/SKPFM. Besides, the film formation and rupture mechanism were illuminated through the spectroscopic analysis, and its role on the propagation of localized corrosion was also discussed. The results demonstrate that the localized corrosion propagates inside the matrix (underneath the surface film layers) and exhibits a filiform-like corrosion morphology. Immersion and polarization tests together with morphology observations indicate that the MZM-0.6Nd has the moderate degradation rate by giving rise to the densification of the film layer, with the corrosion rate of 0.83 mm/y. However, the corrosion rate progressively increased (1.83 mm/y, 3.08 mm/y), as the Nd content increased (1.22%, 1.88%), due to the more large-size phases present in the matrix. It will exacerbate the corrosion resistance by facilitating the localized dissolution of the degradation layers, enhancing the adsorption for Cl− and promoting the mass transport, thereby retarding the self-healing capability and the occurrence of the localized corrosion. The significant improvement in mechanical strength of MZM-0.6Nd, with the ultimate tensile strength and elongation of 224 MPa and 19.2%, making it appear the ductile fracture feature with small dimples. It was attributed to the role of interactions with the fine-grained microstructure, the pinning dislocations, and the strengthening phases dispersedly distributed in the matrix.

The corrosion behaviors of Mg-2Zn-0.2Mn-xCa (denoted as MZM-xCa alloys) in homogenization state have been investigated by immersion test and electrochemical techniques in a simulated physiological condition. The microstructure features were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM) and electron probe microanalysis (EPMA), and the corrosion mechanism was illustrated using atomic force microscope (AFM), X-ray photoelectron spectroscopy (XPS) and confocal laser scanning microscopy (CLSM). The electrochemical and immersion test verify the MZM-0.38% Ca owns the best corrosion performance with the corrosion rate of 6.27 mm/year. Furthermore, the film layer of MZM-0.38% Ca is more compact and denser than that of others. This improvement could be associated with the combined effects of the suitable content of Zn/Ca dissolving into the α-Mg matrix and the modification of Ca-containing compounds by heat-treatment. However, the morphologies were transformed from uniform corrosion to localized pitting corrosion with Ca further addition. It could be explained that the excessive Ca addition can strengthen the nucleation driving force for the second phase formation, and the large volumes fraction of micro-galvanic present interface sites accelerate the nucleation driving force for corrosion propagation. In addition, in vitro biocompatibility tests also show the MZM-0.38% Ca was safe to bone mesenchymal stem cells (BMSCs) and was promising to be utilized as implant materials.

Objective: This study was designed to study the clinical and histopathological characteristics of patients with the scarring folliculitis type acne inversa in Chinese population. Methods: A total of 21 patients with acne inversa and 6 controls without known dermatological disease were recruited from outpatient department of dermatology and orthopedic surgery. Two-millimeter punch biopsies were taken from 8 patients with acne inversa and 6 controls, fixed in formalin, embedded in paraffin and stained with haematoxylin and eosin prior to histopathological analysis. Results: There were 12 patients (57.14%) belonging to the scarring folliculitis type presented with double comedones, papules, nodules, depressed scars, and were mainly Hurley stage I (66.67%). Many of the scarring folliculitis type were smokers (58.33%), some had a history of occupational exposure (41.67%) and some were overweight (50%), the mean BMI of which is 25.18±3.16 kg/m2. Histopathological changes such as perifollicular inflammation can be observed in scarring folliculitis type of acne inversa and controls as well. However, epidermal hyperplasia, follicular hyperplasia, sebaceous gland disappearance, destruction of hair follicle and sebaceous gland, collagen hyperplasia, perivascular inflammation, granulomatous inflammation, Micro thrombus were only seen in scarring folliculitis type. The mean surface area in patients (8073.36±15798.43 μm2) was smaller than that in controls (302059.08±502813.78 μm2), with statistically significant difference. (P = 0.024). Conclusion: The scarring folliculitis type in acne inversa in Chinese population could be characterized by depressed scars, double-ended comedones, epidermal cysts and had high proportion of smokers, or occupational exposure with lower Hurley stage, as well as diminished sebaceous gland. Further studies are needed to clarify the relations between the clinical subtypes of acne inversa and their corresponding genetypes.

In this study, the microstructure characterization, mechanical properties and degradation behaviors of the Mg-xZn-0.1Mn-0.2Ca alloys with various Zn contents were analyzed via the polarization test, electrochemical impedance spectroscopy and the static immersion measurements. Meantime, the surface film layer features and the phase constitutions of the degradation production were characterized via the confocal laser scanning microscopy (3D/CLSM) and scanning electron microscopy. The results indicated that the more secondary phases appeared and the grain sizes were remarkably refined with the further addition of Zn, such as the Ca2Mg6Zn3, Mg2Ca and Mg4Zn7. The mechanical and corrosion resistance of the Mg-xZn-0.1Mn-0.2Ca alloys both initially increased and then decreased as Zn contents increased. Besides, the special anodic phase has been detected in the interior of the matrix, where the Mg2Ca phase with the lower potentials can protect Mg matrix from dissolving in the simulated body fluids (SBF). However, the Ca2Mg6Zn3 phase with the high potentials can accelerate dissolution rate of the Mg matrix. The best mechanical properties and corrosion resistance were obtained in the Mg–1Zn-0.1Mn-0.2Ca alloys, with the corrosion rate of 6.09 mm/y, exhibiting the uniform degradation morphology.

Vascular endothelial growth factor (VEGF), an important angiogenic factor that is able to stimulate the proliferation and migration of endothelial cells, is the best-studied hallmark of angiogenesis. Neovascularization is a major cause of age-related macular degeneration (AMD) which is a leading cause of blindness in the elderly population. Specific molecular inhibitors of VEGF have been proved to be useful in the treatment of AMD. Ranibizumab and Bevacizumab are structurally similar to anti-VEGF drugs in the treatment of AMD. Many studies have indicated that Ranibizumab and Bevacizumab are of roughly equal short-term efficacy and safety, Bevacizumab is an attractive alternative to Ranibizumab due to its lower cost. However, only Ranibizumab has received Food and Drug Administration (FDA) approval for the treatment of macular degeneration. More multicenter clinical trials are required to compare the relative efficacy and safety of these two drugs and some progress has been achieved. This review discusses the clinical effectiveness, safety, cost and other practical implications of Ranibizumab and Bevacizumab.