Micro Electromechanical System Navigation Assists Femoral Extramedullary Alignment Osteotomy in Total Knee Arthroplasty: A Single-Blind Randomizing Study.

OBJECTIVE: A micro-electromechanical system (MEMS) was developed based on spatial alignment and navigation technology to assist femoral extramedullary alignment osteotomy (FEAO) in total knee arthroplasty (TKA). The system can locate and adjust the femoral distal condylar osteotomy (FDCO) to obtain a better femoral prosthesis placement. It is a portable navigation device and provides an innovative approach for FDCO. METHODS: Sixty patients who suffered from severe knee osteoarthritis who underwent unilateral TKA from May 14, 2021 to May 30, 2022 were randomly divided into a MEMS-FEAO group and a conventional femoral intramedullary alignment osteotomy (FIAO) group, with 30 cases in each group for a controlled retrospective study. The hip-knee-ankle angle (HKAA) of the lower limb was measured before and after surgery, the femoral valgus angle (FVA) was measured preoperatively, and the femoral prosthesis valgus angle (FPVA) and the femoral prosthesis flexion angle (FPFA) were measured postoperatively following computed tomography imaging protocols. Measurement data is statistically described as mean ± standard deviation c. The count data is described by frequency (constituent ratio) using the rank sum test. RESULT: A total of 6.7% (2/30) of FEAO compared to 20.0% (6/30) of FIAO cases were postoperative deviations where the HKAA exceeded ±3° of neutral alignment (p < 0.05). The postoperative HKAA was 178.74° ± 1.56° versus 176.64° ± 3.39° (p < 0.05), the HKAA deviation was 1.25° ± 1.56° versus 3.36° ± 3.40° (p < 0.05), and the FPFA was 4.85° ± 2.46° versus 6.60° ± 1.86°(p < 0.05). Therefore, the differences were all statistically significant between the two groups. However, the FPVA was -0.59° ± 2.73° versus -0.80° ± 2.85° (p > 0.05), and there was no statistical significance between the two groups. CONCLUSION: The MEMS-FEAO system can improve the accurate alignment and can be utilized as a locator to obtain the best femoral prosthesis placement in TKA and significantly reduce the rate of poor force line of the lower limb.

Tauroursodeoxycholic acid suppresses endoplasmic reticulum stress in the chondrocytes of patients with osteoarthritis.

The main pathogenic events in osteoarthritis (OA) include loss and abnormal remodeling of cartilage extracellular matrix. The present study aimed to evaluate the protective effect of tauroursodeoxycholic acid on chondrocyte apoptosis induced by endoplasmic reticulum (ER) stress. Articular cartilage tissues were collected from 18 patients who underwent total knee arthroplasty and were analyzed histologically. Subsequently, chondrocyte apoptosis was assessed by TUNEL. Quantitative polymerase chain reaction and western blot analysis were employed to evaluate gene and protein expression, respectively, of ER stress markers, including glucose­regulated protein 78 (GRP78), growth arrest and DNA­damage­inducible gene 153 (GADD153) and caspase­12 along with type II collagen. Chondrocytes obtained from osteoarthritis patients at different stages were cultured in three conditions including: No treatment (CON group), tunicamycin treatment to induce ER stress (ERS group) and tauroursodeoxycholic acid treatment after 4 h of tunicamycin (TDA group); and cell proliferation, apoptosis, function and ER stress level were assessed. Degradation of cartilage resulted in histological damage with more apoptotic cartilage cells observed. Of note, GRP78, GADD153 and caspase­12 mRNA and protein expression increased gradually from grade I to III cartilage tissue, while type II collagen expression decreased. Tunicamycin induced ER stress, as shown by a high expression of ER stress markers, reduced cell proliferation, increased apoptosis and decreased synthesis of type II collagen. Notably, tauroursodeoxycholic acid treatment resulted in the improvement of tunicamycin­induced ER stress. These results indicated that ER stress is highly involved in the tunicamycin­induced apoptosis in chondrocytes, which can be prevented by tauroursodeoxycholic acid.

Synthesis and insecticidal activities of novel pyrazole oxime ether derivatives with different substituted pyridyl rings.

BACKGROUND: Pyrazole oxime ether derivatives with different substituted pyridyl rings represent new types of compounds that possess good insecticidal and acarcidal activity against Aphis laburni Kaltenbach and Tetranychus cinnabarinus. RESULTS: In total, 82 novel pyrazole oxime ether derivatives were synthesized and identified by (1) H NMR, elemental analysis or high-resolution mass spectrometry, and their insecticidal and acarcidal activities were tested against A. laburni Kaltenbach and T. cinnabarinus. Bioassays showed that at a 200 mg L(-1) dosage, one-third of the compounds displayed high insecticidal activity against A. laburni Kaltenbach (> 90%), whereas most of of the compound II series exhibited excellent acarcidal activity against T. cinnabarinus (> 92%). Most compound II series exhibited good activity in both insecticidal and acarcidal tests. In addition, at a low concentration of 10 mg L(-1) , the insecticidal activity of compounds IB9 and IE4 exceeded 90%, and the acarcidal activity of compounds IIB1 and IIB2 was ≥ 95%. CONCLUSION: Structure-activity relationships were also examined. Results suggested that the tert-butoxycarbonyl group, as well as the position between tert-butoxycarbonyl and the atom N of the pyridyl ring, were essential to obtaining the acarcidal activity of the title compounds.

Tricyclo-hex-yl(3,5-dibromo-2-hy-droxy-benzoato-κO)tin(IV).

In the title compound, [Sn(C(6)H(11))(3)(C(7)H(3)Br(2)O(3))], the Sn atom is four-coordinate and possesses a distorted Sn(C(3)O) tetra-hedral geometry, with Sn-C bond lengths in the range 2.132 (6)-2.144 (6) Šand with Sn-O = 2.086 (4) Å. The uncoordinated carboxyl-ate O atom forms a weak contact with the Sn atom, with an Sn⋯O separation of 2.962 (2) Å.