An evaluation of the efficacy of a four-grade fat infiltration classification method, presented for the first time in literature

Exosome-mediated Repair of Intervertebral Disc Degeneration: The Potential Role of miRNAs

Intervertebral disc degeneration (IVDD) is a serious condition that manifests as low back pain, intervertebral disc protrusion, and spinal canal stenosis. At present, the main treatment methods for IVDD are surgical interventions such as discectomy, total disc replacement, and spinal fusion. However, these interventions have shown limitations, such as recurrent lumbar disc herniation after discectomy, lesions in adjacent segments, and failure of fixation. To overcome these shortcomings, researchers have been exploring stem cell transplantation therapy, such as mesenchymal stem cell (MSC) transplantation, but the treatment results are still controversial. Therefore, researchers are in search of new methods that are more efficient and have better outcomes. The exosomes from stem cells contain a variety of bioactive molecules that mediate cell interactions, and these components have been investigated for their potential therapeutic role in the repair of various tissue injuries. Recent studies have shown that MSC-derived miRNAs in exosomes and vesicles have therapeutic effects on nucleus pulposus cells, annulus fibrosus, and cartilage endplate. miRNAs play a role in many cell activities, such as cell proliferation, apoptosis, and cytokine release, by acting on mRNA translation, and they may have immense therapeutic potential, especially when combined with stem cell therapy. This article reviews the current status of research on intervertebral disc repair, especially with regard to the latest research findings on the molecular biological mechanisms of miRNAs in MSC-derived exosomes in intervertebral disc repair.

Sarcopenic obesity and its relation with muscle quality and mortality in patients on chronic hemodialysis

BACKGROUND & AIMS

Sarcopenia is prevalent in patients with end-stage kidney disease (ESKD) on hemodialysis (HD), and is associated with poor outcomes, while obesity may be protective. Sarcopenic obesity is associated with increased frailty, morbidity and mortality in the general population. Myosteatosis, i.e., muscle fat infiltration, has major effects on muscle strength and physical performance, but is poorly investigated in the nephrology setting. In the present study we aimed to assess the association between sarcopenic obesity, as diagnosed by abdominal CT, and mortality. Moreover, the relationship between myosteatosis, sarcopenic obesity and mortality was also investigated.

METHODS

This is a retrospective study in which ESKD patients on HD submitted to unenhanced abdominal CT for clinical reasons at least 6 months after dialysis initiation were evaluated for sarcopenic obesity and myosteatosis, defined as intermuscular fat area and low attenuation muscle area. Sarcopenic obesity was diagnosed in cases of low abdominal skeletal muscle area and high total fat area. Receiver-operating characteristics (ROC) analysis with Youden index was used to determine the cut-off for high total fat area. Intermuscular fat area and low attenuation muscle area were evaluated by applying the Hounsfield unit of interest (-190; -30, and -29; +29 respectively). Cox regression analysis was used to evaluate the association between predictors and mortality risk.

RESULTS

We enrolled 212 patients, aged 68.8 (±14.7) years, 65.5% (139/212) male. Median follow-up was 19.7 (interquartile range [IQR] 2.7-35) months. Sarcopenic obesity was diagnosed in 19.8% of patients and was associated with increased mortality (HR: 3.29 (1.72; 6.27), P < 0.001), and with the presence of myosteatosis. Both intermuscular fat area and low attenuation muscle area were associated with increased mortality in adjusted analyses.

CONCLUSIONS

Patients with sarcopenic obesity have increased myosteatosis. Sarcopenic obesity and myosteatosis are associated with increased mortality in patients on HD.

Knowledge Areas and New Trends in Lumbar Disc Herniation Research: Bibliometrics and Knowledge Mapping Analysis

OBJECTIVE

To determine the coalitions and impact of authors, countries, institutions, and journals, evaluate the knowledge base, find the hotspot trends, and identify the emerging topics in lumbar disc herniation (LDH).

METHOD

The articles related to LDH were obtained from the Web of Science Core Collection on August 21, 2021. Two scientometric software (CiteSpace 5.8.R.1 and VOSviewer 1.6.17) were used to perform bibliometric and knowledge-map analysis.

RESULTS

From the set parameters, 4642 articles were included in the literature. Although the total number of publications fluctuated between 2001 and 2020, a general trend toward increase was observed. Respectively, the most productive country and institution in the field were the United States and Wooridul Spine Hospital. The most active and cited authors were Lee and Weinstein. Spine was the most impactful and cited journal. Weinstein (JAMA 296:2441-2450, 2006) had the highest number of co-citations and Weinstein(N Engl J Med 358:794-810, 2008) had the highest number of citations. The keyword "low back pain" was ranked first for frequency and total link strength, whereas "risk factor" was ranked first for centrality. Topics including pathogenesis (disc herniation), examination methods (MRI), treatment methods (non-surgical treatment, surgical treatment), surgical options (laminectomy, discectomy), clinical observations (double-blind, efficacy, outcome, learning curve), and evaluation of efficacy (meta-analysis) of LDH have been the focus of leading-edge research in 2001-2020.

CONCLUSION

Using bibliometric methods, this study mapped the knowledge map of LDH research in the past 20 years. The study identifies existing trends to provide a framework for further research.