Background: While many reviews have been performed to attempt to provide conclusive evidence regarding the outcomes of mesenchymal stem cells (MSCs) in osteoarthritis treatment, the evidence for MSC treatment in osteoarthritis remains contentious, as these reviews have been limited by the heterogeneous evidence available. Purpose: To pool the results of treatment using intra-articular injections of MSCs without any adjuvant therapies for osteoarthritis. Study Design: Systematic review and meta-analysis. Methods: The review was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. All clinical trials of level 1 or 2 evidence that reported clinical outcomes of patients with osteoarthritis of the knees treated using intra-articular injections of MSCs without any adjuvant therapies were included. Results: A total of 19 studies with 440 knees were included. All studies reported an improvement in the outcomes after intervention. The standardized mean differences (SMDs) for the visual analog scale (VAS) for pain at rest and upon exertion were –1.48 (95% CI, –1.85 to –1.11) and –2.25 (95% CI, –2.64 to –1.85), respectively. The SMDs for the total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and total Knee injury and Osteoarthritis Outcome Score were –1.19 (95% CI, –1.53 to –0.84) and 0.88 (95% CI, 0.66-1.10), respectively. Only the source of MSCs and whether the MSCs were cultured or uncultured were clinically important and statistically significant moderators of the treatment outcome. The use of bone marrow MSCs reduced the VAS for pain by 1.50 (95% CI, 0.04-2.96; P = .04) and reduced the total WOMAC by 23.2 (95% CI, 10.0-36.4; P < .01) as compared with adipose MSCs. The use of cultured MSCs reduced the VAS for pain by 2.19 (95% CI, 0.57-3.81; P < .01) and reduced the total WOMAC by 14.4 (95% CI, 1.21-27.5; P = .03) as compared with uncultured MSCs. Conclusion: Intra-articular injections of MSCs without any adjuvant therapies improves pain and function for osteoarthritis. Significantly better outcomes were obtained with the use of bone marrow MSCs as compared with adipose MSCs and with the use of cultured MSCs as opposed to uncultured MSCs.

Background: The outcomes after high tibial osteotomy (HTO) with augmentation of intra-articular mesenchymal stem cell (MSCs) for medial tibiofemoral osteoarthritis remain controversial. Purpose: To pool existing studies to compare the outcomes of HTO with versus without intra-articular MSC augmentation when performed for medial tibiofemoral osteoarthritis. Study Design: Systematic review; Level of evidence, 3. Methods: The systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included were clinical studies that compared the outcomes of HTO with intra-articular MSC augmentation (MSC group) versus without (control group). Pre- and postoperative outcomes were compared between groups from measures including the Lysholm score, International Knee Documentation Committee (IKDC) score, Knee injury and Osteoarthritis Outcome Score, Hospital for Special Surgery Knee Rating Scale, Tegner score, visual analog scale for pain, arthroscopic and histological grading scales, femorotibial angle, weightbearing line, and posterior tibial slope. Results: We reviewed 4 studies with a total of 224 patients. The MSC group demonstrated significantly greater improvement versus controls in the pooled Lysholm score (weighted mean difference [WMD], 6.64; 95% CI, 0.90 to 12.39) and pooled IKDC score (WMD, 9.21; 95% CI, 4.06 to 14.36), which were within or close to the minimal clinically important difference. Radiological outcomes were similar in both groups, including the femorotibial angle (WMD, –0.01; 95% CI, –1.10 to 1.09), weightbearing line, and posterior tibial slope. The studies were homogeneous, and no publication bias was noted. Conclusion: Intra-articular MSC augmentation for HTO may modestly improve functional outcomes as compared with HTO alone. However, adequate data are lacking to make definitive conclusions regarding the effect of MSC augmentation on pain or arthroscopic and histologic grading.

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Copper wire has become a mainstream bonding material in fine-pitch applications due to the rising cost of gold wire. In recent years, palladium-coated copper (Pd-Cu) wire is being increasingly used to overcome some constraints posed by pure Cu wire. During wire bonding with aluminum bond pads, different intermetallic compound (IMC) phases that have been identified at the bond interface are typically CuAl 2 , CuAl and Cu 9 Al 4 . Copper wire bonds were reported to fail humidity reliability tests and Cu 9 Al 4 was observed to be the corroded IMC layer. However, the corrosion susceptibility of the individual IMCs has not been investigated. There has also been conflicting results on the effect of palladium on the reliability of copper wire bonds reported in literature. This paper compares the corrosion performance of the three types of Cu-Al IMCs in a chloride medium by employing electrochemical potentiodynamic polarization. A comparison was made with pure Cu and Al. The effect of Pd on the IMC corrosion performance was also studied. Among the three CuAl IMCs, Cu 9 Al 4 was observed to have the largest corrosion rate followed by CuAl 2 and CuAl. For the metals, Cu was observed to have the lowest corrosion rate and Al is the most easily corroded. The addition of a few percent of Pd slightly improves the corrosion resistance of the metals and IMCs.