Ribonuclease 5 coordinates signals for the regulation of intraocular pressure and inhibits neural apoptosis as a novel multi-functional anti-glaucomatous strategy.

Glaucoma is a vision-threatening disorder characterized by progressive death of retinal ganglion cells (RGCs), although little is known about therapeutic milestones. Due to its complex and multifactorial pathogenesis, multipronged therapeutic approach is needed. Angiogenin (ANG), now called ribonuclease (RNase) 5, has been previously known as angiogenic factor and more recently its biologic activity is extended to promoting cell survival via its ribonucleolytic activity. Here, we revealed the defect of ANG in human glaucomatous trabecular meshwork (TM) cells and identified novel multiple functions of ANG as an anti-glaucomatous strategy. ANG was highly expressed in normal eyes and normal TM cells compared to glaucomatous TM cells. ANG induced intraocular pressure (IOP) lowering in rat models of both normal and elevated IOP, and as a possible mechanism, activated Akt-mediated signals for nitric oxide (NO) production, an important regulator of IOP in glaucomatous TM cell. Moreover, we demonstrated ANG-induced production of matrix metalloproteinase (MMP)-1 and -3 and rho-kinase inhibition for TM remodeling. For anti-glaucomatous defense optimization, ANG not only elicited immune-modulative pathways via indolamine 2,3-dioxygenase (IDO) activation in TM cells and suppression of Jurkat T cells, but also rescued neural stem cells (NSCs) from apoptosis induced by glaucomatous stress. These results demonstrate that novel multi-functional effects of ANG may have benefits against glaucoma in ocular tissues.

Implant surface factors and bacterial adhesion: a review of the literature.

The microbiota that forms on implant surfaces placed in the human body can be highly resistant to antimicrobial agents and in some cases cause life-threatening infections. Consequently, to limit bacterial attachment to these surfaces and thereby minimize the risk of implant infection, the process of biofilm formation and bacterial attachment must be well-understood. The oral environment is considered to be an excellent model for research into biofilm formation and implant infection, accounting for many studies carried out in the field of dental medicine. Those studies show that the roughness, free energy, and material characteristics of the implant surface largely determine initial bacterial adhesion. This article reviews the relevant literature on these aspects of biofilm formation.

Arthroscopic treatment of pigmented villonodular synovitis involving bilateral shoulders.

Pigmented villonodular synovitis (PVNS) is a lesion of benign proliferative synovium that invades joint, tendon sheath, and bursa. It mainly occurs in 1 joint, the knee joint or hand, and multi-joint invasion is reported to be <1%. Rare cases have been reported of PVNS occurring in the shoulder joint. Generally, total synovectomy is a standard treatment of PVNS. However, complete synovectomy is sometimes impossible because of difficulty of visualization and access to the whole joint and subacromial space. Therefore, recurrence of the disease is always of concern. This article presents a case of 64-year-old patient with pain and swelling of bilateral shoulder joints of 4 months' duration. Physical examination showed atrophy of the deltoid and infraspinatus and a mass-like protrusion on the anterior portion of left shoulder. Active forward elevation was limited to 30 degrees on the right and 90 degrees on the left. Overall synovial hyperplasia and nodular mass was observed on magnetic resonance imaging. Massive rotator cuff tear and invasion of the lesion toward the subacromial space and deltoid muscle was noted as well. Arthroscopic examination revealed a typical finding of PVNS: yellowish brown pigmentation over the overall joint capsule and subacromial space. Arthroscopic total synovectomy without rotator cuff repair was performed for both shoulders. Clinical outcomes showed good pain relief and no recurrence of the disease, although range of motion and muscle strength was not significantly improved, possibly due to accompanied massive rotator cuff tear. Arthroscopic total synovectomy in the treatment of PVNS of the shoulder joint is a minimally invasive and effective method, which makes it possible to access the whole joint space and subacromial space.

Rotator cuff integrity after arthroscopic repair for large tears with less-than-optimal footprint coverage.

PURPOSE: The purpose of this study was to evaluate the clinical results and healing status of rotator cuff repairs with less than 50% footprint coverage. METHODS: During the 18-month period from October 2005 to March 2007, 89 large to massive rotator cuff tears were arthroscopically repaired. Among them, 23 consecutive large to massive rotator cuff tears were repaired completely but with less than 50% of the original footprint. All tears were arthroscopically repaired with suture anchors. Preoperative and postoperative clinical assessments were performed with the Constant score, American Shoulder and Elbow Surgeons score, and pain visual analog scale. The healing status of repaired tendon was evaluated by postoperative magnetic resonance imaging with a focus on tendon integrity, muscle fatty degeneration, and muscle atrophy. RESULTS: The mean follow-up period was 30.2 months (range, 24 to 41 months). At final follow-up visits, American Shoulder and Elbow Surgeons score, Constant score, and score on pain visual analog scale were found to have improved significantly from 40.1, 35.9, and 57.7 to 82.4, 86.6, and 12.3, respectively (P < .01). The overall retear rate was 45.5% (10 cases). However, clinical results showed no difference between the retear group and no retear group. Furthermore, rerupture size was smaller than original tear size in all 10 patients, and no significant progression of fatty degeneration or muscle atrophy of rotator cuff muscles was observed. CONCLUSIONS: Less-than-optimal coverage of the original greater tuberosity footprint during arthroscopic repair of large to massive rotator cuff tears was found to be associated with a relatively high retear rate (45.5%). However, clinical results improved significantly, and no significant difference was observed in the clinical results between the retear and no retear groups. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

A novel magnetic resonance imaging classification of discoid lateral meniscus based on peripheral attachment.

BACKGROUND: In the symptomatic discoid lateral meniscus, the effectiveness of preoperative magnetic resonance imaging (MRI) is not well documented. HYPOTHESIS: Magnetic resonance imaging classification will provide more information to the surgeon in choosing the appropriate treatment methods with the help of arthroscopic findings. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Sixty-seven patients (82 knees) were reviewed. The preoperative MRI was checked in 76 of 82 knees. The Lysholm and Ikeuchi grading scales were evaluated. Images were analyzed from MRI, and findings were classified into 4 categories: no shift, anterocentral shift, posterocentral shift, and central shift. Tear pattern classifications were based on arthroscopic findings: horizontal tear, peripheral tear, horizontal and peripheral tear, posterolateral corner loss, and others. The correlations between MRI classification tear patterns and surgical methods were analyzed using the chi-square test or the Fisher exact test. The sensitivity, specificity, and accuracy of shift in preoperative MRI-according to the existence of peripheral tear when corroborated with arthroscopy-were also analyzed with the chi-square test. Inter- and intraobserver reliability was statistically analyzed by producing the inter- and intraclass correlation coefficient. RESULTS: The mean preoperative Lysholm score was 77.3 (range, 43-97), and the last follow-up Lysholm score had increased to 96.8 (range, 84-100; P < .001). At last follow-up (100% follow-up), the Ikeuchi grading scale scored 48 knees as excellent, 30 as good, and 4 as fair. According to the MRI classification, 43 knees were no shift; 6, anterocentral shift; 15, posterocentral shift; and 12, central shift. Shift-type knees had a significantly larger number of peripheral tears, and repairs were performed in the shift-type knees (55%) more frequently than in the no-shift-type knees (28%). Among 82 knees, 31 were repaired simultaneously after a central partial meniscectomy. CONCLUSION: Magnetic resonance imaging classification provides more information to surgeons in choosing the appropriate treatment methods, although the final decision regarding procedure is made during arthroscopy after thorough analysis of the tear.