Influence of Proteolysis on the Binding Capacity of Flavor Compounds to Myofibrillar Proteins.

Proteolysis occurs extensively during postmortem aging, enzymatic tenderization and fermentation of meat products, whereas less is understood regarding how proteolysis affects meat flavor. Myofibrillar proteins (MP) were extracted from beef longissimus dorsi muscle and subsequently treated with three commercial proteases. The effect of proteolysis on the interactions between the treated MP and butyraldehyde, 2-pentanone, octanal and 2-octanone was investigated. The progress of proteolysis increased the degree of hydrolysis (DH) and the surface hydrophobicity but decreased the turbidity and particle size. Fluorescence-quenching analysis results indicated that the enzymatic treatment generally increased the quenching constant (Ksv) between the treated MP and ketones but decreased the Ksv between the treated MP and aldehydes, and the papain treatment changed the Ksv value to a larger degree than treatment with proteinase K and bromelain. The adsorption assay showed that the proteinase K treatment largely increased the adsorption capacity of the MP to octanal (by 15.8−19.3%), whereas the bromelain treatment significantly reduced the adsorption capacity of the treated MP to butyraldehyde (by 6.0−7.9%) and 2-pentanone (by 9.7−11.9%). A correlation analysis demonstrated a strong positive correlation (0.859, p < 0.05) between the DH of the MP and the adsorption ability of the treated MP to octanal. This study highlighted the significant but complex influence of proteolysis on MP binding capacity to flavor compounds.

Photodynamic therapy for synovial hyperplasia in patients with refractory rheumatoid arthritis: a study protocol for a randomized, double-blind, blank-controlled prospective trial.

BACKGROUND: Persistent synovial hyperplasia with inflammation in rheumatoid arthritis is one of the main pathogeneses of refractory rheumatoid arthritis (RRA). Photodynamic therapy (PDT) causes less trauma than steroid injections or arthroscopic synovectomy while providing stronger targeting and more durable curative effects. The aim of this trial was to evaluate the short-, medium-, and long-term clinical efficacy of PDT when applied as a treatment for RRA synovial hyperplasia and synovitis. METHODS AND ANALYSIS: This protocol is for a single-center, randomized, double-blind, blank-controlled prospective trial. A sample of 126 RRA patients will be randomly divided into 3 groups: the control group, the "PDT once" group, and the "PDT twice" group, with 42 participants per group. The trial will be conducted by the Rheumatology and Immunology Department of the Integrated Hospital of Traditional Chinese Medicine, Southern Medical University. The Ultrasound Compound Score of Synovitis (UCSS) has been selected as the primary outcome measure. The secondary outcome measures include knee joint clinical assessments, ratio of relapse, duration of remission, Disease Activity Score in 28 joints (DAS28), inflammation indexes, serum concentrations of specific antibodies, and changes in articular structures as detected by X-ray scans in the 48th week. The improvement ratios of the UCSS at the 8th, 24th, and 48th weeks (compared with baseline) reflect short-, medium-, and long-term time frames, respectively. ETHICS AND DISSEMINATION: The protocol was approved by the Medical Ethics Committee of the Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, China (Approval No. granted by the ethics committee: NFZXYEC-2017-005) and then entered in the Chinese Clinical Trials Registry under registration number ChiCTR1800014918 (approval date: February 21, 2018). All procedures are in accordance with Chinese laws and regulations and with the Declaration of Helsinki by the World Medical Association (WMA). Any modifications of this protocol during execution will need additional approval from the Ethics Committee of our hospital. TRIAL REGISTRATION NUMBER: ChiCTR1800014918 .

[The correlation study on syndrome differentiation of rheumatoid arthritis and joint high frequency ultrasound performance].

OBJECTIVE: To observe the differential effect of joint ultrasound on the syndrome differentiation of rheumatoid arthritis (RA) by observing the high frequency ultrasound performances among inactive stage and different syndromes in active stage. METHODS: Totally 83 RA patients in the active stage were assigned to the dampness heat syndrome group (DHS, 59 cases)and the cold dampness syndrome group (CDS, 24 cases) according to Chinese medicine (CM) syndrome typing. Besides, 20 RA patients in the remission stage were recruited as the control group (abbreviated as the remission group). By using high frequency ultrasound and power Doppler ultrasound technology, a comparative observation of synovitis, tenosynovitis, synovial blood flow, and bone erosion in the 2nd-5th metacarpophalangeal (MCP) joints, proximal interphalangeal (PIP) joints, wrist joints, knee joints, the second and the fifth metatarsophalangeal (MTP) joints (a total of 24 joints) was performed in all patients. Correlation analyses were performed between the ultrasound performance, laboratory indices, and the disease activity. Ultrasound data of each RA patient were analyzed by their total scores. Χ2 test was used for enumeration data. The measurement data was expressed as x ± s. One-way ANOVA was used for data of normal distribution, while non- parametric test was used for data of non-normal distribution. Correlation analysis of two variables was performed for clinical indicators and ultrasound indicators. Its significance was detected using Pearson correlation. RESULTS: Compared with the remission group, the severity degree of synovitis, tenosynovitis, synovial blood flow, and bone erosion significantly increased in the DHS group (P < 0.01). There was statistical difference in ESR, CRP, anti-CCP, DAS28 score, and the positive rate of RF (P < 0.05, P < 0.01). There was statistical difference in the severity degree of synovitis and synovial blood flow, and DAS28 score in the CDS group (P < 0.05). Compared with the CDS group, there was statistical difference in the four ultrasound indices (P < 0.05, P < 0.01), ESR, CRP, anti-CCP, DAS28 score, and the positive rate of RF in the DHS group (P < 0.05, P < 0.01). There was no statistical difference in G, IgG, IgA, or IgM among the three groups (P > 0.05). There existed positive correlation between ESR and the synovitis degree, synovial blood flow, and bone erosion in the DHS group (r = 0.444, 0.397, 0.486, P < 0.05).There existed positive correlation between ESR and the synovitis degree, bone erosion, and synovial blood flow in the DHS group (r = 0.378, 0.270, P < 0.05). There existed positive correlation between the DAS28 score and the synovitis degree and synovial blood flow in the DHS group (r = 0.304, 0.351, P < 0.05). CONCLUSIONS: The inflammation degree was the most severe in RA patients of DHS. High frequency ultrasound could provide better evidence for Chinese medical syndrome differentiation of RA patients.

[Effect of sanshui baihu decoction on the proliferation of fibroblast-like synoviocytes and its secretion of IL-6 and IL-17].

OBJECTIVE: To observe the effect of Sanshui Baihu Decoction (SBD) containing serum on the proliferation of in vitro cultured fibroblast-like synoviocytes (FLS) derived from rheumatoid arthritis (RA) and osteoarthritis (OA) and its secretion of interleukin-6 (IL-6) and IL-17, and to explore the pharmacological mechanism of SBD. METHODS: The FLS obtained from cultured RA and OA patients' synovial tissue were cultured and passaged in vitro in a routine way. The cultured medium was changed to DMEM with 20% SBD containing serum and cultured for 72 h after cultured for 3 to 6 generations. The proliferation rate of FLS was detected by MTT assay. Levels of IL-6 and IL-17 in the supernatant were detected by ELISA. Leflunomide and saline containing serum were used as positive and negative control respectively. RESULTS: SBD containing serum significantly inhibited the proliferation of RA-FLS and OA-FLS, and decreased the secretion of IL-17 in RA-FLS. Its inhibition efficiency of SBD was equivalent to that of Leflunomide. No obvious inhibition on the secretion of IL-6 in RA-FLS was observed. It had no significant effect on the secretion of IL-17 and IL-6 in OA-FLS. CONCLUSION: SBD could inhibit the proliferation of FLS and the secretion of IL-17 in RA-FLS, which might be one of its pharmacological mechanisms for treating RA.