Investigation of the performance of the menifocal Z gas-permeable bifocal contact lens during continuous wear

Purpose. The Menifocal Z is an alternating vision, concentric, bifocal gas-permeable (GP) contact lens; center distance is connected to near periphery by a smooth transition zone. The lens is produced using tisilfocon A (Menicon Z material), which is approved for up to 30 days of continuous wear (CW). The aim of this study was to evaluate the clinical performance of the Menifocal Z when worn for up to 30 days of CW for 6 months.

Methods. Thirty-five existing GP lens wearers were enrolled in the study. Subjects were fitted with Menifocal Z lenses and follow-up visits were conducted after 2 weeks of daily wear and 1 day, 1 week, 6 weeks, 3 and 6 months of CW. A range of objective and subjective clinical performance measures were assessed, including distance and near visual acuity, the physiological response to CW, and subjective evaluation of vision and comfort.

Results. Twenty-seven subjects (77%) completed the study and eight (23%) discontinued: five (14%) as a result of lens-related problems (four vision, one comfort) and three (9%) as a result of non-lens related reasons. Average CW time achieved by the subjects was 22 ± 2 days. Mean binocular logarithm of the minimum angle of resolution (logMAR) acuities at 6 months were: high contrast distance 0.03 (20/20-), low contrast distance 0.63 (20/80-), and high contrast near 0.26 (20/25, N4). Adverse responses and lens binding were minimal, and there were no significant increases in corneal staining, corneal vascularization, or superior palpebral conjunctival papillae over time (p > 0.05). Problems with night vision (distance and near) with the lenses were the most common difficulties reported by the subjects.

Conclusions. The Menifocal Z appears to be a promising option for presbyopic vision correction, providing successful correction of distance and near vision in a group of experienced GP lens wearers. The hyper Dk tisilfocon A (Menicon Z) material allowed for safe wear of the lenses on a CW basis.

Managing the emerging presbyopic contact lens wearer

The article deals with a study that examined the performance of a new silicone hydrogel multifocal contact lens for emerging presbyopes compared to other forms of correction. Study participants were asked to wear a different lens design for a week at a time. They were divided into the asymptomatic group and the symptomatic group. Results of the study showed that 24 participants had no difficulties with near vision tasks. It also found similar ghosting between the multifocal and habitual corrections for the near tasks under low illumination.

Inhibitory effect of antidepressant drugs on contact hypersensitivity reaction

Background: Contact hypersensitivity (CS) reaction in the skin is T-cell mediated immune reaction which plays a major role in the pathogenesis and chronicity of various inflammatory skin disorders and, like other delayed-type hypersensitivity (DTH) reactions, affords immunity against tumor cells and microbes. CS response is a self-limiting reaction, and interleukin (IL)-10 is considered to be a natural suppressant of cutaneous inflammatory response. Recently, it has been demonstrated that major depression is related to activation of the inflammatory response and elevation of some parameters of cell-mediated immunity. It has been suggested that such activation of the immune system may play a role in etiology of depression. If this immunoactivation is involved in etiology of depression, one would expect that antidepressant agents may have negative immunoregulatory effects. To the best of our knowledge, the effect of antidepressants on contact hypersensitivity has not been studied.

Methods: The aim of the present study was to establish the effect of prolonged desipramine or fluoxetine treatment on CS reaction to picryl chloride.

Results: Antidepressants significantly suppressed CS reaction, fluoxetine by 53% whereas desipramine by 47% compared to positive control. Moreover, desipramine and fluoxetine decreased relative weight of auxillary lymph nodes. Desipramine decreased also relative weight of inguinal lymph nodes and spleens whereas desipramine and fluoxetine increased production of IL-10 in comparison to positive control.

Conclusion: The observed effect of antidepressant drugs on CS reaction is consistent with the hypothesis that T-cell mediated immunity is targeted by antidepressants.

Humanising contact zones : the stories and faces of cross-cultural dialogue

We live in a radically ‘cosmopolitanised’ world, facing a plethora of mostly unwanted or unforeseen cross-cultural encounters as side effects of global trade and global threats (Beck, 2006). The potentially positive role of both cultural tourism and museums in this context has been widely recognised and theorised. But what does cross-cultural dialogue mean for the person experiencing it, and how is it negotiated within time and space? Drawing on a long-term narrative study of global visitors to the Museum of New Zealand Te Papa Tongarewa (Te Papa), I explore cross-cultural meanings empirically through a hermeneutic interpretation embedded in Beck’s ‘cosmopolitan critical theory’. The evidence presented in this research suggests that the individual is the point of departure from which cross-cultural dialogue is humanised by giving it ‘faces’ and stories. I argue that the impact of any travel experience is best understood via the meanings tourists make and negotiate in the long-term.