46 research outputs found

    Photodynamic therapy for acne vulgaris: a randomized, controlled, split-face clinical trial of topical aminolevulinic acid and pulsed dye laser therapy

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    There remains the need for more effective therapeutic options to treat acne vulgaris. Interest in light-based acne treatments has increased, but few randomized, controlled clinical trials assessing the value of photodynamic therapy (PDT) for acne have been reported.We sought to examine the efficacy of PDT using 5-aminolevulinic acid (ALA) and pulsed dye laser therapy in the treatment of acne.We conducted a randomized, controlled, split-face, single-blind clinical trial of 44 patients with facial acne. Patients were randomized to receive three pulsed dye laser treatments to one side of the face after a 60–90 min ALA application time, while the contralateral side remained untreated and served as a control. Serial blinded lesion counts and global acne severity ratings were performed.Global acne severity ratings improved bilaterally with the improvement noted to be statistically significantly greater in treated skin than in untreated skin. Erythematous macules (remnants of previously active inflammatory lesions) decreased in number in treated skin when compared with control skin and there was a transient but significant decrease in inflammatory papules in treated skin when compared with untreated skin. There were no other statistically significant differences between treated and untreated sides of the face in terms of counts of any subtype of acne lesion. Thirty percent of patients were deemed responders to this treatment with respect to improvement in their inflammatory lesion counts, while only 7% of patients responded in terms of noninflammatory lesion counts.PDT with the treatment regimen employed here may be beneficial for a subgroup of patients with inflammatory acne.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79403/1/j.1473-2165.2010.00483.x.pd

    Impact of calcium on salivary α-amylase activity, starch paste apparent viscosity and thickness perception

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    Thickness perception of starch-thickened products during eating has been linked to starch viscosity and salivary amylase activity. Calcium is an essential cofactor for α-amylase and there is anecdotal evidence that adding extra calcium affects amylase activity in processes like mashing of beer. The aims of this paper were to (1) investigate the role of salivary calcium on α-amylase activity and (2) to measure the effect of calcium concentration on apparent viscosity and thickness perception when interacting with salivary α-amylase in starch-based samples. α-Amylase activity in saliva samples from 28 people was assessed using a typical starch pasting cycle (up to 95 °C). The activity of the enzyme (as measured by the change in starch apparent viscosity) was maintained by the presence of calcium, probably by protecting the enzyme from heat denaturation. Enhancement of α-amylase activity by calcium at 37 °C was also observed although to a smaller extent. Sensory analysis showed a general trend of decreased thickness perception in the presence of calcium, but the result was only significant for one pair of samples, suggesting a limited impact of calcium enhanced enzyme activity on perceived thickness

    Perceived managerial and leadership effectiveness in a Korean context: An indigenous qualitative study

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    Multinational corporations (MNCs) across the world have sent an increasing number of managers abroad to leverage unprecedented opportunities in the era of globalization. However, their failure rate has been above 33% for decades, resulting in substantial costs (Puck, Kittler, & Wright, 2008). One of the primary reasons for this failure is a lack of understanding of the national and organizational cultures within the host countries (Festing & Maletzky, 2011). For example, while a number of MNCs have entered the Korean market, several such as Yahoo, Motorola, and Walmart have failed and withdrawn due to the companies’ lack of adjustment to the Korean cultural context (Choe, 2006; Woo, 2013). In spite of the significance of culturally embedded practices, most researchers who have explored management and leadership in Asian countries, whether they were Western or indigenous researchers, have implemented studies using extant Western management and leadership theories derived within the Western cultural context (Leung, 2007; Tsui, 2006). Numerous scholars have claimed that this could be problematic because the findings of such studies may not be applicable to non-Western countries (Li, 2012; Liden & Antonakis, 2009), and may fail to provide insights and understanding of novel contexts or to reveal indigenous aspects of management and leadership (Tsui, 2007). Consequently, there have been increasing calls for indigenous management and leadership research within Asian countries (see Li et al., 2014; Lyles, 2009; Tsui, 2004; Wolfgramm, Spiller, & Voyageur, 2014). Over the past 30 years, managerial effectiveness and leadership effectiveness have been substantially neglected areas of management research (Noordegraaf & Stewart, 2000; Yukl, Gordon, & Taber, 2002). In addition, there has been little agreement on what specific behaviors distinguish effective managers from ineffective ones. Furthermore, more research is needed to examine the managerial and leadership behaviors that are critical for shaping the performance of individuals, groups and organizations (see Borman & Brush, 1993; Cammock, Nilakant & Dakin, 1995; Mumford, 2011; Noordegraaf & Stewart, 2000; Yukl et al., 2002). While most of the research related to managerial and leadership effectiveness has been conducted in the U.S., the few notable non-U.S. studies include that of Cammock et al. (1995) in New Zealand who developed a behavioral lay model of managerial effectiveness using the repertory grid technique. Another notable exception is the cumulative series of perceived managerial and leadership effectiveness studies conducted by Hamlin with various indigenous co-researchers in Western and non-Western countries (see Hamlin & Patel, 2012; Ruiz, Wang, & Hamlin, 2013) using Flanagan’s (1954) critical incident technique (CIT)
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