Long-term television viewing patterns and gray matter brain volume in midlife

Brain Imaging and Behavior - The purpose of this study was to investigate whether long-term television viewing patterns, a common sedentary behavior, in early to mid-adulthood is associated with...     

Effect of low intensity laser irradiation on surgically created bony defects in rats

Low intensity lasers have been used by clinicians to improve healing and reduce pain in humans. Lasing also results in new bone formation around hydroxyapatite implants and a significant increase in the total bone area. However, the exact mechanism of cell biostimulation by laser is still unclear. This study biochemically assessed the effects of low intensity laser (Gallium-Arsenide) using 4 and 22.4 mW cm(-2) power density on the bone healing process after surgically creating bony cavities in rat mandibles. Rats (n = 24) were divided into two groups each treated with specific energy, 4 or 22.4 mW cm(-2), for 3 min each day post-surgery. Surgical cavities were created on both sides of the mandible: the left served as an untreated control, the right was treated with laser. All rats were sacrificed after 1, 2 and 4 weeks of treatment. In the newly formed callus, accumulation of radiocalcium and alkaline phosphatase activity was measured to indicate osteogenic activity. One-way anova with repeated measures showed that the low intensity laser using 4 mW cm(-2) power density significantly increased radiocalcium accumulation from 2 weeks post-surgery, whereas 22.4 mW cm(-2) had no effect. No changes were noted in the activity of alkaline phosphatase with the laser treatment. These results suggest that laser therapy of low power density is effective on the bone healing process in artificially created osseous cavities by affecting calcium transport during new bone formation.     

First carpometacarpal arthroplasty with ligamentous reconstruction: a long-term follow-up

Background

The purpose of the present study is to evaluate a single surgeon’s short, intermediate, and long-term clinical, functional, and radiographic outcomes with a trapeziectomy with flexor carpi radialis (FCR) suspension arthroplasty without tendon interposition (LRSA).

Methods

Twenty-one patients underwent 26 FCR suspension arthroplasties without tendon interposition by a single senior surgeon. All patients had Eaton stage III and IV carpometacarpal (CMC) osteoarthritis. The Patient-Rated Wrist and Hand Evaluation (PRWHE) and Quick Disabilities of Arm, Shoulder, and Hand (QuickDASH) were used to evaluate functional outcomes. A comprehensive strength and range of motion evaluation was performed to evaluate clinical outcomes. Plain radiographs at rest and with maximal pinch were performed to evaluate for arthroplasty space subsidence.

Results

The LRSA exhibited consistent clinical and functional outcomes throughout postoperative follow-up. As the average patient age and time from surgery increased, range of motion (ROM) and PRWHE scores stayed relatively constant, while lateral tip and tip pinch strength deteriorated with time. The LRSA prevented the proximal migration of the first metacarpal in all but one patient. No patients required revision arthroplasty following LRSA.

Conclusions

This study demonstrates the consistent short, intermediate, and long-term clinical, functional, and radiographic outcomes following a trapeziectomy with FCR suspension arthroplasty.

     

The role of reactive oxygen species in diabetes-induced anomalies in embryos of Cohen diabetic rats

The role of the antioxidant defense mechanism in diabetes-induced anomalies was studied in the Cohen diabetes-sensitive (CDs) and -resistant (CDr) rats, a genetic model of nutritionally induced type 2 diabetes mellitus. Embryos, 12.5-day-old, of CDs and CDr rats fed regular diet (RD) or a diabetogenic high-sucrose diet (HSD) were monitored for growth retardation and congenital anomalies. Activity of superoxide dismutase (SOD) and catalase-like enzymes and levels of ascorbic acid (AA), uric acid (UA), and dehydroascorbic acid (DHAA) were measured in embryonic homogenates. When fed RD, CDs rats had a decreased rate of pregnancy, and an increased embryonic resorption. CDs embryos were smaller than CDr embryos; 46% were maldeveloped and 7% exhibited neural tube defects (NTDs). When fed HSD, rate of pregnancy was reduced, resorption rate was greatly increased (56%; P < .001), 47.6% of the embryos were retrieved without heart beats, and 27% exhibited NTD. In contrast, all the CDr embryos were normal when fed RD or HSD. Activity of SOD and catalase was not different in embryos of CDs and CDr rats fed RD. When fed HSD, levels of AA were significantly reduced, the ratio DHAA/AA was significantly increased, and SOD activity was not sufficiently increased when compared to embryos of CDr. The reduced fertility of the CDs rats, the growth retardation, and NTD seem to be genetically determined. Maternal hyperglycemia seems to result in environmentally induced embryonic oxidative stress, resulting in further embryonic damage.