Mechanisms of ferroptosis with immune infiltration and inflammatory response in rotator cuff injury

The processes driving ferroptosis and rotator cuff (RC) inflammation are yet unknown. The mechanism of ferroptosis and inflammation involved in the development of RC tears was investigated. The Gene Expression Omnibus database was used to obtain the microarray data relevant to the RC tears for further investigation. In this study, we created an RC tears rat model for in vivo experimental validation. For the additional function enrichment analysis, 10 hub ferroptosis-related genes were chosen to construct the correlation regulation network. In RC tears, it was discovered that genes related to hub ferroptosis and hub inflammatory response were strongly correlated. The outcomes of in vivo tests showed that RC tears were related to Cd68-Cxcl13, Acsl4-Sat1, Acsl3-Eno3, Acsl3-Ccr7, and Ccr7-Eno3 pairings in regulating ferroptosis and inflammatory response. Thus, our results show an association between ferroptosis and inflammation, providing a new avenue to explore the clinical treatment of RC tears.

Novel Prediction Method Applied to Wound Age Estimation: Developing a Stacking Ensemble Model to Improve Predictive Performance Based on Multi-mRNA

(1) Background: Accurate diagnosis of wound age is crucial for investigating violent cases in forensic practice. However, effective biomarkers and forecast methods are lacking. (2) Methods: Samples were collected from rats divided randomly into control and contusion groups at 0, 4, 8, 12, 16, 20, and 24 h post-injury. The characteristics of concern were nine mRNA expression levels. Internal validation data were used to train different machine learning algorithms, namely random forest (RF), support vector machine (SVM), multilayer perceptron (MLP), gradient boosting (GB), and stochastic gradient descent (SGD), to predict wound age. These models were considered the base learners, which were then applied to developing 26 stacking ensemble models combining two, three, four, or five base learners. The best-performing stacking model and base learner were evaluated through external validation data. (3) Results: The best results were obtained using a stacking model of RF + SVM + MLP (accuracy = 92.85%, area under the receiver operating characteristic curve (AUROC) = 0.93, root-mean-square-error (RMSE) = 1.06 h). The wound age prediction performance of the stacking models was also confirmed for another independent dataset. (4) Conclusions: We illustrate that machine learning techniques, especially ensemble algorithms, have a high potential to be used to predict wound age. According to the results, the strategy can be applied to other types of forensic forecasts.

Postoperative Analgesic Efficacy and Safety of Ropivacaine Plus Diprospan for Preemptive Scalp Infiltration in Patients Undergoing Craniotomy: A Prospective Randomized Controlled Trial

BACKGROUND

Preemptive injection of local anesthetics can prevent postoperative pain at the incision site, but the analgesic effect is insufficient and is maintained only for a relatively short period of time. Diprospan is a combination of quick-acting betamethasone sodium phosphate and long-acting betamethasone dipropionate. Whether Diprospan as an adjuvant to local anesthetic can achieve postcraniotomy pain relief has not been studied yet.

METHODS

This is a prospective, single-center, blinded, randomized, controlled clinical study, which included patients ages 18 and 64 years, with American Society of Anaesthesiologists (ASA) physical statuses of I to III, scheduled for elective supratentorial craniotomy. We screened patients for enrollment from September 3, 2019, to August 15, 2020. The final follow-up was completed on February 15, 2021. Eligible patients were randomly assigned to either the Diprospan group, who received incision-site infiltration of 0.5% ropivacaine plus Diprospan (n = 48), or the control group, who received 0.5% ropivacaine alone (n = 48), with a distribution ratio of 1:1. Primary outcome was the cumulative sufentanil (μg) consumption through patient-controlled analgesia (PCA) within 48 hours after surgery. Primary analysis was performed based on the intention-to-treat (ITT) principle.

RESULTS

Baseline characteristics were not significantly different between the 2 groups ( P > .05). In the Diprospan group, the cumulative sufentanil consumption through PCA was 5 (0-16) µg within 48 hours postoperatively, which was significantly lower than that in the control group (38 [30.5-46] µg; P < .001).

CONCLUSIONS

Infiltration of ropivacaine and Diprospan can achieve satisfactory postoperative pain relief after craniotomy; it is a simple, easy, and safe technique, worth clinical promotion.

Bioinformatics analysis of sequential gene expression profiling after skin and skeletal muscle wound in mice

It is of great value to use bioinformatics methods to screen the core differentially expressed genes (DEGs) at different times after mouse skin and skeletal muscle wound, and to explore the relationship between them and the wound age. To this end, we downloaded the gene expression profiles of GSE140517 and GSE23006 from the NCBI-GEO gene database, used GEO2R online tools and Venn diagrams to screen out DEGs at different times and common-DEGs. The Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) channel analysis were carried out through the DAVID website respectively. Use STRING tool to build a Protein-protein Interaction (PPI) network, and use Cytoscape software to screen out core DEGs. The results showed that 13, 53, 43 and 13 core DEGs were screened out in the 6 h, 12 h, 24 h and common-DEGs group after wound. There were 7 core DEGs (Cxcl2, Cxcl3, Il1b, Ptgs2, Cxcl1, Timp1, Ccl3) in both the different time point and the common DEGs group. Meanwhile, there are 1 core DEGs (Ccl4) specifically expressed in the 6 h, 29 specifically expressed core DEGs (Isg20, Rtp4, Fcgr1, Ifi44, Trim30a, etc.) in the 12 h, and 18 specifically expressed core DEGs (Ccr7, Myd88, Igsf6, Ccr2, Gpsm3, etc.) in the 24 h, there are 6 core DEGs (Ccl4, Ccl7, Saa3, Cxcl5, Ccl2, Lcn2) specifically expressed in the common-DEGs group. The results of GO and KEGG analysis showed that the deterioration and exudation of the inflammatory response were the main cause at 6 h after wound. In addition to inflammation at 12 h and 24 h, the systemic immune response against viral and bacterial infections also gradually increased. In summary, the core DEGs selected in this study have combined characteristics, consistent with the healing function at the corresponding time point, and they are also has specificity and correlation with wound age. Therefore, by detecting the changes in the expression of co-expressed core DEGs at different times after wound, as well as detecting specific expressed DEGs at a specific time point or a specific period of time, it is very promising to provide help for the wound age estimation. However, limited by the GSE140517 gene expression profile in the database, only the difference in gene expression at different times within 24 h after wound was explored, and the research on the late wound age still needs to be further in-depth.

Investigating Transcriptional Dynamics Changes and Time-Dependent Marker Gene Expression in the Early Period After Skeletal Muscle Injury in Rats

Following skeletal muscle injury (SMI), from post-injury reaction to repair consists of a complex series of dynamic changes. However, there is a paucity of research on detailed transcriptional dynamics and time-dependent marker gene expression in the early stages after SMI. In this study, skeletal muscle tissue in rats was taken at 4 to 48 h after injury for next-generation sequencing. We examined the transcriptional kinetics characteristics during above time periods after injury. STEM and maSigPro were used to screen time-correlated genes. Integrating 188 time-correlated genes with 161 genes in each time-related gene module by WGCNA, we finally identified 18 network-node regulatory genes after SMI. Histological staining analyses confirmed the mechanisms underlying changes in the tissue damage to repair process. Our research linked a variety of dynamic biological processes with specific time periods and provided insight into the characteristics of transcriptional dynamics, as well as screened time-related biological indicators with biological significance in the early stages after SMI.

Dexamethasone as a ropivacaine adjuvant to pre-emptive incision-site infiltration analgesia in pediatric craniotomy patients: A prospective, multicenter, randomized, double-blind, controlled trial

BACKGROUND

Dexamethasone added to incision-site infiltration has been routinely used to reduce pain after tonsillectomy in children. However, this has not been studied in pediatric craniotomy patients yet. We hypothesized that incision-site infiltration with a combination of ropivacaine and dexamethasone might provide superior analgesia to ropivacaine alone in pediatric craniotomy patients.

METHODS

In this multicenter, double-blind, randomized, controlled trial, children aged 2-12 years, scheduled for craniotomy, were prospectively enrolled at two study centers, from September 2, 2019, to July 5, 2020. Eighty children were randomly assigned (1:1) to either ropivacaine plus dexamethasone group who received pre-emptive incision-site infiltration with 0.2% ropivacaine plus 0.025% dexamethasone, or ropivacaine group who received 0.2% ropivacaine alone. Primary outcome was the modified Children's Hospital of Eastern Ontario Pain Scale (mCHEOPS) at 24 h postoperatively. Primary analysis was performed using the modified intention-to-treat principle.

RESULTS

Pre-emptive incision-site infiltration with ropivacaine plus dexamethasone had a reduced pain score of 2.0, compared with the pain score of 2.9 in the ropivacaine group, at 24 h postoperatively (mean difference -0.9, 95% confidence interval [CI], -1.7 to -0.2; p = .019). Estimated median of the time of first rescue analgesic demand was 24 h in the ropivacaine plus dexamethasone group and 8.5 h in the ropivacaine group [hazard ratio 0.43, 95% CI 0.24 to 0.08; Log-rank p = .0025]. No adverse events related to incision-site infiltration with dexamethasone were observed in this study.

DISCUSSION

Dexamethsone reduces the local production of pro-inflammatory factors after tissue damage and as a ropivacaine adjuvant for incision-site infiltration reduced the pain scores by 31% at 24 h postoperatively. The results were similar to several prior studies on to tonsillectomy patients. However, this changes on pain scores might has limited clinical significance.

CONCLUSIONS

The addition of dexamethasone to ropivacaine for preoperative incision-site infiltration has better postoperative analgesic effect than ropivacaine alone in pediatric craniotomy patients.

Novel insights into wound age estimation: combined with "up, no change, or down" system and cosine similarity in python environment

Wound age estimation is a complex, multifactorial issue. It is considered to have great practical significance that combining multi-biomarkers and multi-methods for injury time estimation. We optimized our earlier "up, no change, or down" model by adding data on the expression levels of mRNAs encoding ABHD2, MAD2L2, and ARID5A, and we converted the relative quantitative expression levels of seven genes into a vector rather than a color model. We used Python to derive the cosine similarity (CS) between a test set and the vector matrix; the highest similarity most accurately reflected the injury time. For the optimized model, the internal and external verifications were approximately 0.71 and 0.66, respectively. The good double-blinded results indicated that the model was stable and reliable. In summary, we used a vector matrix and cosine similarities derived by Python to mine the levels of genes expressed in contused skeletal muscle. We are the first to combine several biomarkers and methods for wound age estimation.

Gene expression in mouse muscle over time after nickel pellet implantation

The transition metal nickel is used in a wide variety of alloys and medical devices. Nickel can cause a range of toxicities from allergy in humans to tumors when implanted in animals. Several microarray studies have examined nickel toxicity, but so far none have comprehensively profiled expression over an extended period. In this work, male mice were implanted with a single nickel pellet in the muscle of the right leg with the left leg used as a control. At 3 week intervals up to 12 months, nickel concentrations in bioflulids and microarrays of surrounding tissue were used to track gene expression patterns. Pellet biocorrosion resulted in varying levels of systemic nickel over time, with peaks of 600 μg L-1 in serum, while global gene expression was cyclical in nature with immune related genes topping the list of overexpressed genes. IPA and KEGG pathway analyses was used to attribute overall biological function to changes in gene expression levels, supported by GO enrichment analysis. IPA pathways identified sirtuin, mitochondria, and oxidative phosphorylation as top pathways, based predominantly on downregulated genes, whereas immune processes were associated with upregulated genes. Top KEGG pathways identified were lysosome, osteoclast differentiation, and phasgosome. Both pathway approaches identified common immune responses, as well as hypoxia, toll like receptor, and matrix metalloproteinases. Overall, pathway analysis identified a negative impact on energy metabolism, and a positive impact on immune function, in particular the acute phase response. Inside the cell the impacts were on mitochondria and lysosome. New pathways and genes responsive to nickel were identified from the large dataset in this study which represents the first long-term analysis of the effects of chronic nickel exposure on global gene expression.

Time course analysis of large-scale gene expression in incised muscle using correspondence analysis

Studying the time course of gene expression in injured skeletal muscle would help to estimate the timing of injuries. In this study, we investigated large-scale gene expression in incision-injured mouse skeletal muscle by DNA microarray using correspondence analysis (CA). Biceps femoris muscle samples were collected 6, 12, and 24 hours after injury, and RNA was extracted and prepared for microarray analysis. On a 2-dimensional plot by CA, the genes (row score coordinate) located farther from each time series (column score coordinate) had more upregulation at particular times. Each gene was situated in 6 subdivided triangular areas according to the magnitude of the relationship of the fold change (FC) value at each time point compared to the control. In each area, genes for which the ratios of two particular FC values were close to 1 were distributed along the two border lines. There was a tendency for genes whose FC values were almost equal to be distributed near the intersection of these 6 areas. Therefore, the gene marker candidates for estimation of the timing of injuries were detectable according to the location on the CA plot. Moreover, gene sets created by a specific gene and its surrounding genes were composed of genes that showed similar or identical fluctuation patterns to the specific gene. In various analyses on these sets, significant gene ontology term and pathway activity may reflect changes in specific genes. In conclusion, analyses of gene sets based on CA plots is effective for investigation of the time-dependent fluctuation in gene expression after injury.