Changes in Nup62 content affect contact-induced differentiation of cultured myoblasts.

Differentiation of cultured skeletal myoblasts is induced by extrinsic signals that include reduction in ambient mitogen concentration and increased cell density. Using an established murine myoblast cell line (C2C12), we have found that experimental reduction of the nucleoporin p62 (Nup62) content of myoblasts enhances differentiation in high-mitogen medium, while forced expression of Nup62 inhibits density-induced differentiation. In contrast, differentiation of myoblasts induced by low-mitogen medium was unaffected by ectopic Nup62 expression. Further analyses suggested that Nup62 content affects density-induced myoblast differentiation through a mechanism involving activation of p38 MAP kinase. Nuclear pore complex (NPC) composition, in particular changes in NUP62 content, may be altered during viral infection, differentiation, and in neoplastic growth. The results support a functional role for changes in Nup62 composition in NPCs and density-induced myogenic differentiation, and suggest a link between loss of Nup62 content and induction of an intracellular stress signaling pathways.

A method of evaluating helmet rotational acceleration protection using the Kingston Impact Simulator (KIS Unit).

OBJECTIVE: Helmet use is the primary form of head protection against traumatic brain injury. Although helmet designs have proven to be effective in reducing the incidence of skull fracture and major traumatic brain injury, there is little evidence that helmets protect against concussion. Linear and rotational accelerations are important mechanisms underlying concussion, yet current testing protocols do not account for rotational acceleration. Technical considerations have prevented a valid, accurate, and reproducible testing paradigm. Our objectives were to design a novel helmet-testing methodology that accurately and reliably measures rotational acceleration at injury-relevant impact forces, locations, and planes and to evaluate differences in rotational force protection in commercially available helmets. SETTING: Laboratory study. INTERVENTION: The Kingston Impact Simulator (KIS unit) was used to study 10 commercially available hockey helmets. The rotational acceleration force protection was measured in the horizontal, coronal, and sagittal planes at each of 12 predetermined impact locations. RESULTS: Mean peak unhelmeted and helmeted accelerations at all impact locations and planes ranged from 63 to 28.6 g and from 26.8 to 8.0 g, respectively. The percent reduction in rotational acceleration for all test helmets ranged from 6.4% to 84%. Statistically significant differences in rotational acceleration between manufacturers and within a helmet brand were identified. CONCLUSIONS: KIS is a novel testing methodology that identifies rotation force protection within and between hockey helmet models and manufacturers at different impact location and planes. This information may be useful in improving future helmet design and construction to provide maximal protection against the forces causing concussion.

Gastric Parastomal Hernia: A Case Report of a Rare yet Fascinating Clinical Entity.

A 58-year-old female with the prior history of diabetes mellitus (DM) presented with nausea, malaise, and abdominal pain of two days duration. Also, in the past, she was treated for a necrotized rectum from a retroperitoneal infection leading to a colostomy in the left lower quadrant (LLQ) of the abdomen. The physical examination findings were highly suggestive for a parastomal hernia. As a part of her workup and treatment, the initial abdominal CT demonstrated the presence of the gastric contents into the hernia sac leading to the gastric obstruction. The patient responded well to the conservative management using nasogastric (NG) suction, intravenous (IV) line maintenance, clinical assessment, frequent vital sign monitoring, and initiating the nothing per oral (NPO) regimen. Following the successful conservative approach, the patient opted to undergo surgical treatment in the future. This case report and associated literature search represent a rare case of a parastomal hernia with protruding gastric contents, which was successfully treated with conservative management.

Performance of Eye Protectors for Squash and Racquetball.

In brief Although squash and racquetball eye protectors are available and many people wear them, eye injuries still exist. The authors studied the ability of the 13 eye protectors currently available in Canada to protect the players' eyes. The eye guards were mounted on a headform, and balls were thrown at it at speeds from 50 to 100 mph. This was recorded on high-speed film that was analyzed to determine ball speed, lens or frame deformation, and damage during impact. Eye contact with protectors having lenses was confirmed only once in 54 impacts. All 17 hits to the open eye guards produced ball-eye contact. The authors suggest that standards for eye protectors should be established.

The Ice Hockey Helmet: How Effective Is It?

Thicker liners, fewer openings, and more protection over the temporal area in newer models of ice hockey helmets have made them more effective in reducing the potential for serious head injury.