Efficacy of polypropylene mesh coated with bioresorbable membrane for abdominal wall defects in mice.

Incisional hernias due to trauma, infection, or tumor are a common abdominal wall defect. Repair of these defects when autogenous tissue is insufficient or inadequate often results in abdominal tissue adhesion. These adhesions often lead to complications such as intestinal obstruction and enterocutaneous fistula. Previous reports have shown that application of prosthetic materials, such as polypropylene mesh and anionic polysaccharides, has been effective in reducing the amount of tissue adhesion. However, some tissue adhesion still occurs with application of these materials when previously described methodologies are used. We evaluated the efficacy of a novel surgical approach that combines the application of Sepramesh, a coated polypropylene mesh, and Seprafilm, composed of anionic polysaccharides (both products from Genzyme, Cambridge, MA), in the repair of abdominal wall hernias. We report that combined application of these 2 materials in a "sandwich technique", by placing the peritoneum between the Seprafilm and Sepramesh, further reduces (and in some instances prevents) tissue adhesion after abdominal wall defects in mice. Moreover, our combined treatment markedly decreased tissue inflammation after hernia repair.

The effects of tea polyphenolic compounds on hair loss among rodents.

The objective of this study was to examine the effects of polyphenolic compounds, present in noncommercially available green tea, on hair loss among rodentts. In an experimental study, we randomly assigned 60female Balb/black mice, which had developed spontaneous hair loss on the head, neck and dorsal areas into two equal groups; A (experimental) and B (control). Group A received 50% fraction of polyphenol extract from dehydrated green tea in their drinking water for six months. Group B received regular drinking water. Both groups were fed regular rodent diets (Purina Rodent Chow 5001) and housed individually in polycarbonate cages. The results showed that 33% of the mice in experimental Group A, who received polyphenol extract in their drinking water, had significant hair regrowth during six months of treatment (p = 0.014). No hair growth was observed among mice in the control group, which received regular water.

The effects of tea polyphenolic compounds on hair loss among rodents.

The objective of this study was to examine the effects of polyphenolic compounds, present in noncommercially available green tea, on hair loss among rodents. In an experimental study, we randomly assigned 60 female Balb/black mice, which had developed spontaneous hair loss on the head, neck and dorsal areas into two equal groups; A (experimental) and B (control). Group A received 50% fraction of polyphenol extract from dehydrated green tea in their drinking water for six months. Group B received regular drinking water. Both groups were fed regular rodent diets (Purina Rodent Chow 5001) and housed individually in polycarbonate cages. The results showed that 33% of the mice in experimental Group A, who received polyphenol extract in their drinking water, had significant hair regrowth during six months of treatment (p = 0.014). No hair growth was observed among mice in the control group, which received regular water.

Skin tumors in aging Long Evans rats.

We report 25 cases of skin neoplasm observed among 30 Long Evans rats serving as controls in a psychosocial behavioral study conducted in the Vivarium at Charles R. Drew University, Los Angeles, CA. The animals were 10 weeks old at the beginning of the study. All the skin tumors developed at 18 to 26 months of age and slowly enlarged over a period of 9 months. Multiple nodules occurred in 8 males and 6 females. None of the tumors regressed. The tumors were located around the hind leg and dorso-medial area and measured 1 to 2 cm. Physical examination revealed firm well demarcated dermal masses. Most of the tumor nodules were intradermal, and some had a central ulcerated or keratin-filled core. Microscopic examination performed on some of the tumors showed findings of classic Keratoacanthoma, whereas others showed histologic features suggestive of squamous cell carcinoma. These findings indicate a high rate (83%) of spontaneous skin neoplasms among aging Long Evans rats. To our knowledge, such a high rate of skin neoplasms in aged rodents has not been described in the literature. Furthermore, further studies should be undertaken to confirm these findings and to assess whether these rodents might serve as a model for studying the alterations in the immune system with aging.