Photobiomodulation for knee osteoarthritis: a model-based dosimetry study.

LED-based photobiomodulation (LED-PBM) for the treatment of knee osteoarthritis (KOA) is a promising technology. However, the light dose at the targeted tissue, which dominates the phototherapy effectiveness, is difficult to measure. This paper studied the dosimetric issues in the phototherapy of KOA by developing an optical model of the knee and performing Monte Carlo (MC) simulation. The model was validated by the tissue phantom and knee experiments. In the study, we investigated the effect of luminous characteristics of the light source, such as divergence angle, wavelength and irradiation position, on the treatment doses for PBM. The result showed that the divergence angle and the wavelength of the light source have a significant impact on the treatment doses. The optimal irradiation location was on both sides of the patella, where the largest dose could reach the articular cartilage. This optical model can be used to determine the key parameters in phototherapy and help the phototherapy of KOA patients.

Diacylglycerol acyltransferase inhibitory new meroterpenes from the seeds of Psoralea corylifolia, and their structure-activity relationship study.

Five new meroterpenes, 12α-Psoracorylifol F (1), 7ß,8α-hydroxy-12ß-Psoracorylifol F (2), 8-ketone-Cyclobakuchiol C (3), 7α,8ß-hydroxy-12ß-Cyclobakuchiol C (4) and 8α-hydroxy-Cyclobakuchiol C (5) together with six known compounds (6-11) were isolated from seeds of Psoralea corylifolia, and their structures were elucidated on the basis of spectroscopic and physicochemical analyses. All the isolates were evaluated for in vitro inhibitory activity against DGAT1/2. Among them, compounds 1-6 were found to exhibit selective inhibitory activity on DGAT1 with IC50 values ranging from 61.5 ± 1.1 to 89.1 ± 1.2 µM.

Two new sesquiterpenes from the stems of Tripterygium wilfordii.

Two new ß-dihydroagarofuran-type sesquiterpenes 1ß,2α,6α,8ß,15- pentaacetoxy- 9α-benzoyloxy- ß-dihydroagarofuran (1) and 1ß,2ß,6α,15-tetraacetoxy-9ß-benzoyloxy- ß-dihydroagarofuran (2), together with five known abietane diterpenoids (3-7) were isolated from ethyl acetate extract of stems of Tripterygium wilfordii. Their structures were elucidated on the basis of detailed spectroscopic and physico-chemical analyses. All the isolates were evaluated for in vitro inhibitory activity against A549, HOS and MCF-7. Among them, compounds 4 and 5 exhibited manifest inhibition on A549, HOS and MCF-7 cancer cell lines.

Applications of Light Emitting Diodes in Health Care.

Light emitting diodes (LEDs) have become the main light sources for general lighting, due to their high lumen efficiency and long life time. Moreover, their high bandwidth and the availability of diverse wavelength contents ranging from ultraviolet to infrared empower them with great controllability in tuning brightness, pulse durations and spectra. These parameters are the essential ingredients of the applications in medical imaging and therapies. Despite the fast advances in both LED technologies and their applications, few reviews have been seen to link the controllable emission properties of LEDs to these applications. The objective of this paper is to bridge this gap by reviewing the main control techniques of LEDs that enable creating enhanced lighting patterns for imaging and generating effective photon doses for photobiomodulation. This paper also provides the basic mechanisms behind the effective LED therapies in treating cutaneous and neurological diseases. The emerging field of optogenetics is also discussed with a focus on the application of LEDs. The multidisciplinary topics reviewed in this paper can help the researchers in LEDs, imaging, light therapy and optogenetics better understand the basic principles in each other's field; and hence to stimulate the application of LEDs in health care.

A Compressed Sensing-Based Wearable Sensor Network for Quantitative Assessment of Stroke Patients.

Clinical rehabilitation assessment is an important part of the therapy process because it is the premise for prescribing suitable rehabilitation interventions. However, the commonly used assessment scales have the following two drawbacks: (1) they are susceptible to subjective factors; (2) they only have several rating levels and are influenced by a ceiling effect, making it impossible to exactly detect any further improvement in the movement. Meanwhile, energy constraints are a primary design consideration in wearable sensor network systems since they are often battery-operated. Traditionally, for wearable sensor network systems that follow the Shannon/Nyquist sampling theorem, there are many data that need to be sampled and transmitted. This paper proposes a novel wearable sensor network system to monitor and quantitatively assess the upper limb motion function, based on compressed sensing technology. With the sparse representation model, less data is transmitted to the computer than with traditional systems. The experimental results show that the accelerometer signals of Bobath handshake and shoulder touch exercises can be compressed, and the length of the compressed signal is less than 1/3 of the raw signal length. More importantly, the reconstruction errors have no influence on the predictive accuracy of the Brunnstrom stage classification model. It also indicated that the proposed system can not only reduce the amount of data during the sampling and transmission processes, but also, the reconstructed accelerometer signals can be used for quantitative assessment without any loss of useful information.