Multispectral Optoacoustic Tomography Enables In Vivo Anatomical and Functional Assessment of Human Tendons.

Tendon injuries resulting from accidents and aging are increasing globally. However, key tendon functional parameters such as microvascularity and oxygen perfusion remain inaccessible via the currently available clinical diagnostic tools, resulting in disagreements on optimal treatment options. Here, a new noninvasive method for anatomical and functional characterization of human tendons based on multispectral optoacoustic tomography (MSOT) is reported. Healthy subjects are investigated using a hand-held scanner delivering real-time volumetric images. Tendons in the wrist, ankle, and lower leg are imaged in the near-infrared optical spectrum to utilize endogenous contrast from Type I collagen. Morphology of the flexor carpi ulnaris, carpi radialis, palmaris longus, and Achilles tendons are reconstructed in full. The functional roles of the flexor digitorium longus, hallicus longus, and the tibialis posterior tendons have been visualized by dynamic tracking during toe extension-flexion motion. Furthermore, major vessels and microvasculature near the Achilles tendon are localized, and the global increase in oxygen saturation in response to targeted exercise is confirmed by perfusion studies. MSOT is shown to be a versatile tool capable of anatomical and functional tendon assessments. Future studies including abnormal subjects can validate the method as a viable noninvasive clinical tool for tendinopathy management and healing monitoring.

Clinical characteristics and prognostic factors of open globe injuries in a North Spain population: a 10-year review.

OBJECTIVES: To describe the epidemiologic and clinical characteristics of open globe injuries (OGIs) treated in a tertiary hospital and analyse predictors of visual outcome. METHODS: This retrospective observational study included all patients with OGIs admitted to Cruces University Hospital between 2010 and 2020. The descriptive analysis included demographic data, type of injury classified as "rupture", "penetration", "perforation", or "intraocular foreign body", trauma mechanism and setting, injury zone, Ocular Trauma Score, delay to surgery, length of hospital stay, antibiotic prophylaxis, initial and final best corrected visual acuity (BCVA), complications and further surgery. Univariate analysis and logistic regression were performed to identify prognostic factors, based on final BCVA. RESULTS: Overall, 207 OGI cases were reported. The most common type of injuries were ruptures caused by domestic falls. Notably, 44.4% of eyes developed phthisis bulbi. In the univariate analysis, the following variables were significantly linked to visual outcome: age > 60 years, "rupture", "fall", posterior and/or combined zones of injury, lens damage, retinal/choroidal detachment, initial BCVA of no light perception, and Ocular Trauma Score ≤ 2 (p < 0.001). Delay to surgery, length of stay and further surgery did not have prognostic value. In the logistic regression, initial BCVA of no light perception (p < 0.001) and injury zone III (p = 0.005) remained significant predictors of poor outcome. CONCLUSIONS: In the population studied, most OGIs were caused by domestic falls usually affecting elderly patients with comorbidities. Visual outcome depended on patients´ specific characteristics and the nature of the trauma itself, whereas environmental factors failed to show any prognostic value.

Transient PKCα shuttling to the immunological synapse is governed by DGKζ and regulates L-selectin shedding.

Considerable evidence indicates that diacylglycerol (DAG) generation at the immunological synapse (IS) determines T cell functions by regulating the duration and amplitude of Ras/ERK signals. The exact mechanism by which DAG regulates Ras/ERK activation downstream of the T cell receptor (TCR) nonetheless remains poorly understood. Here we characterize PKCα as a previously unrecognized component of the machinery that translates cell receptor occupancy into Ras/ERK-propagated signals. We show transient translocation of PKCα to the IS, mediated by DAG generation at the contact area. Diacylglycerol kinase (DGK)ζ negatively regulated PKCα translocation kinetics, whereas PKCα activity limited its own persistence at the IS. Coordinated activation of DGKζ and PKCα in response to antigen recognition regulated the amplitude and duration of Ras/ERK activation; this in turn mediated early processes of T cell surface proteolysis such as L-selectin shedding. Analysis of DGKζ-deficient mice further showed that increased DAG signaling is translated to downstream elements of this pathway, as reflected by enhanced PKCα-dependent L-selectin shedding. We propose that early activation of a DAG-PKCα axis contributes to the mechanisms by which antigen affinity translates into TCR biological responses.