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Background: pH MRI may provide useful information to evaluate metabolic disruption following ischemia. Radiofrequency amplitude‐based creatine chemical exchange saturation transfer (CrCEST) ratiometric MRI is pH‐sensitive, which could but has not been explored to examine muscle ischemia. Purpose: To investigate skeletal muscle energy metabolism alterations with CrCEST ratiometric MRI. Study Type: Prospective. Animal Model: Seven adult New Zealand rabbits with ipsilateral hindlimb muscle ischemia. Field Strength/Sequence: 3 T/two MRI scans, including MRA and CEST imaging, were performed under two B1 amplitudes of 0.5 and 1.25 μT after 2 hours of hindlimb muscle ischemia and 1 hour of reperfusion recovery, respectively. Assessment: CEST effects of two energy metabolites of creatine and phosphocreatine (PCrCEST) were resolved with the multipool Lorentzian fitting approach. The pixel‐wise CrCEST ratio was quantified by calculating the ratio of the resolved CrCEST peaks under a B1 amplitude of 1.25 μT to those under 0.5 μT in the entire muscle. Statistical Tests: One‐way ANOVA and Pearson's correlation. P < 0.05 was considered statistically significant. Results: MRA images confirmed the blood flow loss and restoration in the ischemic hindlimb at the ischemia and recovery phases, respectively. Ischemic muscles exhibited a significant decrease of PCr at the ischemia (under both B1 amplitudes) and recovery phases (under B1 amplitude of 0.5 μT) and significantly increased CrCEST from normal tissues at both phases (under both B1 levels). Specifically, CrCEST decreased, and PCrCEST increased with the CrCEST ratio. Significantly strong correlations were observed among the CrCEST ratio, and CrCEST and PCrCEST under both B1 levels (r > 0.80). Data Conclusion: The CrCEST ratio altered substantially with muscle pathological states and was closely related to CEST effects of energy metabolites of Cr and PCr, suggesting that the pH‐sensitive CrCEST ratiometric MRI is feasible to evaluate muscle injuries at the metabolic level. Evidence Level: 2 Technical Efficacy Stage: 1 [ABSTRACT FROM AUTHOR]

Objective: Our aim was to evaluate the capacity of the human salivary histatin-1-functionalized methacrylic gelatin scaffold to control osteochondral tissue regeneration and repair in vivo in rabbits with major temporomandibular joint dimensional abnormalities. Materials and Methods: In order to compare human salivary histatin-1-functionalized methacrylic gelatin scaffolds to the Blank and Gel-MA hydrogel groups, scaffolds were implanted into osteochondral lesions of a critical size (3 × 3 mm) in the anterior region of the condyle of the temporomandibular joint in New Zealand white rabbits. At 4 weeks after implantation, the repair was evaluated using macroscopic examination, histology, and micro-CT analysis. Results: In the comparison of the composite scaffold group with the Blank and Gel-MA groups, analysis of the healed tissue revealed an improved macroscopic appearance in the composite scaffold group. Regeneration was induced by host cell migration in the Hst1/Gel-MA scaffold group. Conclusions: The current study offers a viable method for in vivo cartilage repair that does not require cell transplantation. Future clinical applications of this strategy's optimization have many potential advantages. [ABSTRACT FROM AUTHOR]

The Asia-Pacific region is renowned to harbor nearly half of the global hot spots of biodiversity. Accordingly, many endemic species of boletes have already been recorded from this geographic region. However, the majority of the specific descriptions of reported boletoid species follow classical concepts of taxonomy, and by comparison only a few taxa have been corroborated by modern molecular techniques. In this study, we focused on specimens in a new clade uncovered by our previous studies. By careful reexamination of macroscopic and microscopic characters of Boletus granulopunctatus, originally described from Japan, and Xerocomus mcrobbii, originally described from New Zealand, we discovered a new genus and species Amoenoboletus miraculosus from Sabah, Malaysia. In addition, three new combinations in Amoenoboletus are proposed, and a dichotomous key to species in the genus is provided. The phylogenetically close relationship among Amoenoboletus species suggests a tight geographic correlation in the Asia-Pacific region. [ABSTRACT FROM AUTHOR]

The avascular structure and lack of regenerative cells make the repair of osteochondral defects in the temporomandibular joint (TMJ) highly challenging in the clinic. To provide a viable treatment option, we developed a methacrylated gelatin (Gel-MA) hydrogel functionalized with human salivary histatin-1 (Hst1). Gel-MA is highly biocompatible, biodegradable, and cost-effective. Hst1 is capable of activating a series of cell activities, such as adhesion, migration, differentiation, and angiogenesis. To evaluate the efficacy of Hst1/Gel-MA, critical-size osteochondral defects (3 mm in diameter and 3 mm in depth) of TMJ in New Zealand white rabbits were surgically created and randomly assigned to one of the three treatment groups: (1) control (no filling material); (2) Gel-MA hydrogel; (3) Hst1/Gel-MA hydrogel. Samples were retrieved 1, 2, and 4 weeks post-surgery and subjected to gross examination and a series of histomorphometric and immunological analyses. In comparison with the control and Gel-MA alone groups, Hst1/Gel-MA hydrogel was associated with significantly higher International Cartilage Repair Society score, modified O'Driscoll score, area percentages of newly formed bone, cartilage, collagen fiber, and glycosaminoglycan, and expression of collagen II and aggrecan. In conclusion, Hst1/Gel-MA hydrogels significantly enhance bone and cartilage regeneration, thus bearing promising application potential for repairing osteochondral defects. [ABSTRACT FROM AUTHOR]