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ObjectivesRecent studies indicate that glucose metabolism is altered in rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS). Hexokinases (HKs) catalyse the first step in glucose metabolism, and HK2 constitutes the principal HK inducible isoform. We hypothesise that HK2 contributes to the synovial lining hypertrophy and plays a critical role in bone and cartilage damage.MethodsHK1 and HK2 expression were determined in RA and osteoarthritis (OA) synovial tissue by immunohistochemistry. RA FLS were transfected with either HK1 or HK2 siRNA, or infected with either adenovirus (ad)-GFP, ad-HK1 or ad-HK2. FLS migration and invasion were assessed. To study the role of HK2 in vivo, 108 particles of ad-HK2 or ad-GFP were injected into the knee of wild-type mice. K/BxN serum transfer arthritis was induced in HK2F/F mice harbouring Col1a1-Cre (HK2Col1), to delete HK2 in non-haematopoietic cells.ResultsHK2 is particular of RA histopathology (9/9 RA; 1/8 OA) and colocalises with FLS markers. Silencing HK2 in RA FLS resulted in a less invasive and migratory phenotype. Consistently, overexpression of HK2 resulted in an increased ability to migrate and invade. It also increased extracellular lactate production. Intra-articular injection of ad-HK2 in normal knees dramatically increased synovial lining thickness, FLS activation and proliferation. HK2 was highly expressed in the synovial lining after K/BxN serum transfer arthritis. HK2Col1 mice significantly showed decreased arthritis severity, bone and cartilage damage.ConclusionHK2 is specifically expressed in RA synovial lining and regulates FLS aggressive functions. HK2 might be an attractive selective metabolic target safer than global glycolysis for RA treatment.

Forensic examination of digital audio, video, and images frequently requires transforming multimedia data from one format to another. The transformative activity may cause changes to the administrative elements of the file but leave the multimedia streams unchanged and intact. However, the forensic science community has a method knowledge gap in accurately determining if the multimedia streams changed or remained the same in the transformative processes. This paper illustrates the practical use of multimedia stream hashing as a forensic method for verifying multimedia content. A universal stream hashing tool decodes the multimedia stream data at rest in a file container. Subsequently, it calculates the data stream hash using reference video, audio, and image codecs. This paper illustrates that the multimedia stream hashing method can accurately confirm the integrity of digital images, videos, and audio following transmission, transcoding, or re‐containerization. Our findings confirmed that stream hashing could accurately detect changes in multimedia streams during transcoding. Furthermore, the stream hashing method can also accurately detect matching multimedia streams. In addition, this paper verified the forensic use of the multimedia stream hash method while establishing the error rate for its use. The hash algorithms used in stream hashing have zero false negative rates by design. However, the false positive (error rate) is extremely low and depends on hashing algorithm. Finally, we recommend the forensic science community adopt the multimedia stream hashing method as an initial testing method. The method can verify a multimedia stream's conversion (transcoding) from one codec to another using FFmpeg. Highlights: Re‐encoding of multimedia streams must be transparent for forensic examinations.Multimedia stream hashing is a stream integrity verification method used in forensic science.Multimedia stream hashing has an extremely low potential for a false positive (error rate). [ABSTRACT FROM AUTHOR]

The average DC offset values of recordings produced on nine small digital audio recorders were evaluated to determine if they demonstrated characteristics meaningful for forensic audio authenticity examinations when submitted audio files are compared with test recordings made using exemplar digital recorders. Five audio formats (PCM WAV, ADPCM WAV, MP3, WMA, and DSS) were tested with no input, using the internal microphone(s), and with two Olympus external microphones. The average DC offset values were calculated using sound editing, digital analysis, and scientific computing programs. Based on the standard deviations of the DC offsets in these recordings, their wide variation and inconsistency probably preclude meaningful comparisons between one-minute submitted digital audio recordings and exemplars in authenticity examinations. [ABSTRACT FROM AUTHOR]

The article reports on the applications of forensic audio in law and investigations. Topics discussed include requirements for digital audio evidence, modern challenges for the forensic audio examiner and the growing concern for privacy rights. The use of probabilistic methods in the analysis and presentation of scientific evidence is explored.

The article discusses the trends in forensic audio. Forensic audio enhancement is said to increase the intelligibility of voice information or improve the signal to noise ratio of a target signal by reducing the effects or interferences that mask it. Digital recordings on optical disc, flash memory and solid-state recorders are the majority of audio media presented to the forensic examiner. Developments in digital audio authentication are also cited.