An advantage of the powder-bed-based metal additive manufacturing (AM) processes is that the powder can be reused. The powder reuse or recycling times directly affect the affordability of the additively manufactured parts, especially for the AM of titanium parts. This study examines the influence of powder reuse times on the characteristics of Ti-6Al-4V powder, including powder composition, particle size distribution (PSD), apparent density, tap density, flowability, and particle morphology. In addition, tensile samples were manufactured and evaluated with respect to powder reuse times and sample locations in the powder bed. The following findings were made from reusing the same batch of powder 21 times for AM by selective electron beam melting: (i) the oxygen (O) content increased progressively with increasing reuse times but both the Al content and the V content remained generally stable (a small decrease only); (ii) the powder became less spherical with increasing reuse times and some particles showed noticeable distortion and rough surfaces after being reused 16 times; (iii) the PSD became narrower and few satellite particles were observed after 11 times of reuse; (iv) reused powder showed improved flowability; and (v) reused powder showed no measurable undesired influence on the AM process and the samples exhibited highly consistent tensile properties, irrespective of their locations in the powder bed. The implications of these findings were discussed.

Oral squamous cell carcinoma (OSCC) is a common and lethal malignancy. Thus, improvement in current knowledge of molecular changes associated with OSCC is urgently needed to explore novel avenues of diagnostics and treatment of this disease. While aberrant expression of long non‑coding RNAs (lncRNAs) has been functionally associated with certain types of cancer, including lung, breast and prostate carcinomas, their expression pattern and biological relevance in OSCC is currently unknown. In the present study, the relative abundance of a collection of lncRNAs in tissue or saliva samples from OSCC patients was investigated. It was shown that subsets of lncRNAs are expressed across non‑tumor, tumor and metastatic tissue samples. Some detected lncRNAs were shown to be aberrantly expressed in cases of oral cancer and metastasis. Moreover, whole saliva contained a detectable amount of some lncRNAs, which appeared to be potential markers for OSCC. These findings suggest that the detection of lncRNAs in saliva may be used as a noninvasive and rapid diagnostic tool for the diagnosis of oral cancer.

†These authors contributed equally to this work.The final envelopment of most herpesviruses occurs at Golgi or post-Golgi compartments, such as the trans Golgi network (TGN); however, the final envelopment site of human herpesvirus 6 (HHV-6) is uncertain. In this study, we found novel pathways for HHV-6 assembly and release from T cells that differed, in part, from those of alphaherpesviruses. Electron microscopy showed that late in infection, HHV-6-infected cells were larger than uninfected cells and contained many newly formed multivesicular body (MVB)-like compartments that included small vesicles. These MVBs surrounded the Golgi apparatus. Mature virions were found in the MVBs and MVB fusion with plasma membrane, and the release of mature virions together with small vesicles was observed at the cell surface. Immunoelectron microscopy demonstrated that the MVBs contained CD63, an MVB/ late endosome marker, and HHV-6 envelope glycoproteins. The viral glycoproteins also localized to internal vesicles in the MVBs and to secreted vesicles (exosomes). Furthermore, we found virus budding at TGNassociated membranes, which expressed CD63, adaptor protein (AP-1) and TGN46, and CD63 incorporation into virions. Our findings suggest that mature HHV-6 virions are released together with internal vesicles through MVBs by the cellular exosomal pathway. This scenario has significant implications for understanding HHV-6's maturation pathway.

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