Browsing by Subject "Wounds and Injuries"

Now showing 1 - 2 of 2
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    Long-term survival after traumatic brain injury: a population-based analysis controlled for nonhead trauma
    (Ovid Technologies (Wolters Kluwer) - Lippincott Williams & Wilkins, 2014-01) Brown, Allen W.; Leibson, Cynthia L.; Mandrekar, Jay; Ransom, Jeanine E.; Malec, James F.; Department of Physical Medicine and Rehabilitation, IU School of Medicine
    OBJECTIVE: To examine the contribution of co-occurring nonhead injuries to hazard of death after traumatic brain injury (TBI). PARTICIPANTS: A random sample of Olmsted County, Minnesota, residents with confirmed TBI from 1987 through 1999 was identified. DESIGN: Each case was assigned an age- and sex-matched, non-TBI "regular control" from the population. For "special cases" with accompanying nonhead injuries, 2 matched "special controls" with nonhead injuries of similar severity were assigned. MEASURES: Vital status was followed from baseline (ie, injury date for cases, comparable dates for controls) through 2008. Cases were compared first with regular controls and second with regular or special controls, depending on case type. RESULTS: In total, 1257 cases were identified (including 221 special cases). For both cases versus regular controls and cases versus regular or special controls, the hazard ratio was increased from baseline to 6 months (10.82 [2.86-40.89] and 7.13 [3.10-16.39], respectively) and from baseline through study end (2.92 [1.74-4.91] and 1.48 [1.09-2.02], respectively). Among 6-month survivors, the hazard ratio was increased for cases versus regular controls (1.43 [1.06-2.15]) but not for cases versus regular or special controls (1.05 [0.80-1.38]). CONCLUSIONS: Among 6-month survivors, accounting for nonhead injuries resulted in a nonsignificant effect of TBI on long-term mortality.
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    Using a continuum model to predict closure time of gaps in intestinal epithelial cell layers
    (Wiley Blackwell (Blackwell Publishing), 2013-03) Arciero, Julia C.; Mi, Qi; Branca, Maria; Hackam, David; Swigon, David; Department of Mathematical Sciences, School of Science
    A two-dimensional continuum model of collective cell migration is used to predict the closure of gaps in intestinal epithelial cell layers. The model assumes that cell migration is governed by lamellipodia formation, cell-cell adhesion, and cell-substrate adhesion. Model predictions of the gap edge position and complete gap closure time are compared with experimental measures from cell layer scratch assays (also called scratch wound assays). The goal of the study is to combine experimental observations with mathematical descriptions of cell motion to identify effects of gap shape and area on closure time and to propose a method that uses a simple measure (e.g., area) to predict overall gap closure time early in the closure process. Gap closure time is shown to increase linearly with increasing gap area; however, gaps of equal areas but different aspect ratios differ greatly in healing time. Previous methods that calculate overall healing time according to the absolute or percent change in gap area assume that the gap area changes at a constant rate and typically underestimate gap closure time. In this study, data from scratch assays suggest that the rate of change of area is proportional to the first power or square root power of area.