Factors Influencing Noise Following Primary Ceramic-on-Ceramic Total Hip Arthroplasty.

BACKGROUND: The noise associated with ceramic-on-ceramic (CoC) total hip arthroplasty (THA) has been a concerning issue, while its underlying causes remain unclear. METHODS: We conducted a retrospective analysis of 119 patients (174 primary CoC THAs) who had a mean follow-up of 28 months (range, 12 to 106). A questionnaire was designed to collect information on nature, frequency, onset, duration, and impact of the noise. Postoperative x-rays were evaluated. Clinical evaluations, including Harris and Oxford hip scores, were documented at follow-up time points (6 weeks, 3 months, 6 months, and 1 year). RESULTS: Of the 174 hips, 31.6% reported noise, including 26 popping (14.9%), 24 clicking (12.1%), and 5 grinding (2.9%). No patients reported squeaking. Noisy hips had lower age (P = .009) and body mass index (P = .019). Among patients with developmental dysplasia of the hip, 17 of 55 hips reported noise associated with smaller cup anteversion angle (P = .004), greater body height (P = .022), and larger acetabular cup size (P = .049). Noise typically began at a mean of 193 days (range, 1 to 2,598) after surgery and disappeared spontaneously in 50.9% of hips before final follow-up, with an average disappearance time of 211 days (range, 60 to 730). Noise did not affect daily life in 74.5% of patients, while 26.9% of patients who had popping reported painful sensations. One patient experienced joint dislocation, and another experienced a ceramic liner fracture during follow-up. No statistical difference was observed in outcome scores between noise and silent groups at 4 follow-up time points. CONCLUSIONS: Incidence of noise after primary CoC THA is relatively high. Smaller cup anteversion and larger acetabular cup size were associated with noise production in patients who had developmental dysplasia of the hip.

Lactate-upregulated NADPH-dependent NOX4 expression via HCAR1/PI3K pathway contributes to ROS-induced osteoarthritis chondrocyte damage.

Increasing evidence shows that metabolic factors are involved in the pathological process of osteoarthritis (OA). Lactate has been shown to contribute to the onset and progression of diseases. While whether lactate is involved in the pathogenesis of OA through impaired chondrocyte function and its mechanism remains unclear. This study confirmed that serum lactate levels were elevated in OA patients compared to healthy controls and were positively correlated with synovial fluid lactate levels, which were also correlated with fasting blood glucose, high-density lipoprotein, triglyceride. Lactate treatment could up-regulate expressions of the lactate receptor hydroxy-carboxylic acid receptor 1 (HCAR1) and lactate transporters in human chondrocytes. We demonstrated the dual role of lactate, which as a metabolite increased NADPH levels by shunting glucose metabolism to the pentose phosphate pathway, and as a signaling molecule up-regulated NADPH oxidase 4 (NOX4) via activating PI3K/Akt signaling pathway through receptor HCAR1. Particularly, lactate could promote reactive oxygen species (ROS) generation and chondrocyte damage, which was attenuated by pre-treatment with the NOX4 inhibitor GLX351322. We also confirmed that lactate could increase expression of catabolic enzymes (MMP-3/13, ADAMTS-4), reduce the synthesis of type II collagen, promote expression of inflammatory cytokines (IL-6, CCL-3/4), and induce cellular hypertrophy and aging in chondrocytes. Subsequently, we showed that chondrocyte damage mediated by lactate could be reversed by pre-treatment with N-Acetyl-l-cysteine (NAC, ROS scavenger). Finally, we further verified in vivo that intra-articular injection of lactate in Sprague Dawley (SD) rat models could damage cartilage and exacerbate the progression of OA models that could be countered by the NOX4 inhibitor GLX351322. Our study highlights the involvement of lactate as a metabolic factor in the OA process, providing a theoretical basis for potential metabolic therapies of OA in the future.

Human mesenchymal stem cell therapy in severe COVID-19 patients: 2-year follow-up results of a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Long-term effects of human mesenchymal stem cell (MSC) treatment on COVID-19 patients have not been fully characterized. The aim of this study was to evaluate the safety and efficacy of a MSC treatment administered to severe COVID-19 patients enrolled in our previous randomized, double-blind, placebo-controlled clinical trial (NCT04288102). METHODS: A total of 100 patients experiencing severe COVID-19 received either MSC treatment (n = 65, 4 × 107 cells per infusion) or a placebo (n = 35) combined with standard of care on days 0, 3, and 6. Patients were subsequently evaluated 18 and 24 months after treatment to evaluate the long-term safety and efficacy of the MSC treatment. Outcomes measured included: 6-min walking distance (6-MWD), lung imaging, quality of life according to the Short Form 36 questionnaire (SF-36), COVID-19-related symptoms, titers of SARS-CoV-2 neutralizing antibodies, tumor markers, and MSC-related adverse events (AEs). FINDINGS: Two years after treatment, a marginally smaller proportion of patients had a 6-MWD below the lower limit of the normal range in the MSC group than in the placebo group (OR = 0.19, 95% CI: 0.04-0.80, Fisher's exact test, p = 0.015). At month 18, the general health score from the SF-36 was higher in the MSC group than in the placebo group (50.00 vs. 35.00, 95% CI: 0.00-20.00, Wilcoxon rank sum test, p = 0.018). Total severity score of lung imaging and the titer of neutralizing antibodies were similar between the two groups at months 18 and 24. There was no difference in AEs or tumor markers at the 2-year follow-up between the two groups. INTERPRETATION: Long-term safety was observed for the COVID-19 patients who received MSC treatment. However, efficacy of MSC treatment was not significantly sustained through the end of the 2-year follow-up period. FUNDING: The National Key Research and Development Program of China (2022YFA1105604, 2020YFC0860900, 2022YFC2304401), the specific research fund of The Innovation Platform for Academicians of Hainan Province (YSPTZX202216) and the Fund of National Clinical Center for Infectious Diseases, PLA General Hospital (NCRC-ID202105,413FZT6).

Budd-Chiari Syndrome: The "inferior vena cava reverse-flow" sign and "jet-blood" sign on CT and MRI.

OBJECTIVE: To investigate the CT and MR features of "inferior vena cava(IVC) reverse-flow" sign and "jet-blood" sign in Budd-Chiari Syndrome (BCS). METHODS: The liver CT and/or MRI plain scan and dynamic enhancement of 107 cases of BCS diagnosed by DSA and/or clinic were collected, including 17 patients with hepatic vein obstruction type, 79 patients with IVC obstruction type, and 11 patients with mixed type. The manifestations of IVC reverse-flow sign and jet-blood sign in the latter two type BCS (90cases) imaging were analyzed. RESULTS: 1) The incidence of IVC reverse-flow sign in the IVC obstruction type and mixed type was 93.3 %(83/90), which was manifested as: The contrast agent was shown below the level of renal veins in the hepatic arterial phase enhancement, while no contrast agent was shown above it at the same time. 2) The incidence of jet-blood sign in membrane-perforated subtype was 100 %(15/15) or 16.7 %(15/90), which was manifested as: The low density/signal dots appeared within full of contrast agent at the superior liver segment IVC on axial slices in arterial phase of CT/MRI enhancement, or the low signal line within agent presented above the IVC membrane on coronal image in equilibrium phase of MR enhancement. 3) Other imaging findings: 75 cases of membrane, 18 cases of membrane calcification, 27 cases of abnormal hepatic vein, 76 cases of abnormal structure of IVC, 18 cases of thrombus/cancer embolus in hepatic vein and/or IVC. There were 65 cases of abnormal liver appearance; 71 cases of abnormal liver enhancement; 21 cases of hepatic vein unsynchronous enhancement. Anastomotic branches among the hepatic veins open with comma sign in 54 cases; dilatation of intraspinal and paravertebral veins, azygos and hemiazygos veins in 90 cases(100 %, 90/90) or 96 cases(89.7 %, 96/107). CONCLUSIONS: The "IVC reverse-flow" sign is a specific CT and MR sign of IVC type and mixed type BCS, and the "jet-blood" sign is a characteristic CT and MR sign of membrane-perforated subtype BCS.

Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.

PURPOSE: To investigate the clinical and imaging characteristics of computed tomography (CT) in novel coronavirus pneumonia (NCP) caused by SARS-CoV-2. MATERIALS AND METHODS: A retrospective analysis was performed on the imaging findings of patients confirmed with COVID-19 pneumonia who had chest CT scanning and treatment after disease onset. The clinical and imaging data were analyzed. RESULTS: Fifty patients were enrolled, including mild type in nine, common in 28, severe in 10 and critically severe in the rest three. Mild patients (29 years) were significantly (P<0.03) younger than either common (44.5 years) or severe (54.7) and critically severe (65.7 years) patients, and common patients were also significantly (P<0.03) younger than severe and critically severe patients. Mild patients had low to moderate fever (<39.1 °C), 49 (98%) patients had normal or slightly reduced leukocyte count, 14 (28%) had decreased counts of lymphocytes, and 26 (52%) patients had increased C-reactive protein. Nine mild patients were negative in CT imaging. For all the other types of NCP, the lesion was in the right upper lobe in 30 cases, right middle lobe in 22, right lower lobe in 39, left upper lobe in 33 and left lower lobe in 36. The lesion was primarily located in the peripheral area under the pleura with possible extension towards the pulmonary hilum. Symmetrical lesions were seen in 26 cases and asymmetrical in 15. The density of lesion was mostly uneven with ground glass opacity as the primary presentation accompanied by partial consolidation and fibrosis. CONCLUSION: CT imaging presentations of NCP are mostly patchy ground glass opacities in the peripheral areas under the pleura with partial consolidation which will be absorbed with formation of fibrotic stripes if improved. CT scanning provides important bases for early diagnosis and treatment of NCP.