OBJECTIVE: The aim of this study was to clone and express Hev b 3 and to obtain the immunologic active and soluble recombinant allergen for diagnosis of SB-associated latex allergy.
METHODS: A complementary DNA (cDNA) coding for Hev b 3 was amplified from RNA of fresh latex collected from Malaysian rubber trees (Hevea brasiliensis). PCR primers were designed according to sequences of internal peptide fragments of natural (n) Hev b 3. The 5'-end sequence was obtained by specific amplification of cDNA ends. The recombinant (r) Hev b 3 was produced in Escherichia coli as a 6xHis tagged protein. Immunoblotting and inhibition assays were performed to characterize the recombinant allergen.
RESULTS: An Hev b 3 cDNA clone of 922 bp encoding a protein of 204 amino acid residues corresponding to a molecular weight of 22.3 kd was obtained. In immunoblots 29/35, latex-allergic patients with SB revealed IgE binding to rHev b 3, as did 4 of 15 of the latex-sensitized group. The presence of all IgE epitopes on rHev b 3 was shown by its ability to abolish all IgE binding to nHev b 3. Hev b 3 is related to Hev b 1 by a sequence identity of 47%. Cross-reactivity between these 2 latex allergens was illustrated by the large extent of inhibition of IgE binding to nHev b 1 by rHev b 3.
CONCLUSION: rHev b 3 constitutes a suitable in vitro reagent for the diagnosis of latex allergy in patients with SB. The determination of the full sequence of Hev b 3 and the production of the recombinant allergen will allow the epitope mapping and improve diagnostic reagents for latex allergy.
OBJECTIVE: This study aimed to evaluate the utility and usability of ScreenMen.
METHODS: This study used both qualitative and quantitative methods. Healthy men working in a banking institution were recruited to participate in this study. They were purposively sampled according to job position, age, education level, and screening status. Men were asked to use ScreenMen independently while the screen activities were being recorded. Once completed, retrospective think aloud with playback was conducted with men to obtain their feedback. They were asked to answer the System Usability Scale (SUS). Intention to undergo screening pre- and postintervention was also measured. Qualitative data were analyzed using a framework approach followed by thematic analysis. For quantitative data, the mean SUS score was calculated and change in intention to screening was analyzed using McNemar test.
RESULTS: In total, 24 men participated in this study. On the basis of the qualitative data, men found ScreenMen useful as they could learn more about their health risks and screening. They found ScreenMen convenient to use, which might trigger men to undergo screening. In terms of usability, men thought that ScreenMen was user-friendly and easy to understand. The key revision done on utility was the addition of a reminder function, whereas for usability, the revisions done were in terms of attracting and gaining users' trust, improving learnability, and making ScreenMen usable to all types of users. To attract men to use it, ScreenMen was introduced to users in terms of improving health instead of going for screening. Another important revision made was emphasizing the screening tests the users do not need, instead of just informing them about the screening tests they need. A Quick Assessment Mode was also added for users with limited attention span. The quantitative data showed that 8 out of 23 men (35%) planned to attend screening earlier than intended after using the ScreenMen. Furthermore, 4 out of 12 (33%) men who were in the precontemplation stage changed to either contemplation or preparation stage after using ScreenMen with P=.13. In terms of usability, the mean SUS score of 76.4 (SD 7.72) indicated that ScreenMen had good usability.
CONCLUSIONS: This study showed that ScreenMen was acceptable to men in terms of its utility and usability. The preliminary data suggested that ScreenMen might increase men's intention to undergo screening. This paper also presented key lessons learned from the beta testing, which is useful for public health experts and researchers when developing a user-centered mobile Web app.