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Jennifer Corwin-Buell, Denise Callahan, Deborah McGrath, Kimberly Millard, Gary Mosehauer, Nitasha R Phatak Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USACorrespondence: Nitasha R Phatak, Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA, Tel +1 585-413-6397, Email Nitasha.Phatak@bausch.comPurpose: This study was conducted to evaluate and compare the in vitro disinfection efficacies of six commercial lens cleaning and disinfecting products for planned replacement soft contact lenses.Methods: Disinfection efficacies of five multi-purpose solutions (MPSs) and one hydrogen peroxide solution (HPS) as control were evaluated in the presence of organic soil according to the International Organization for Standardization (ISO, Geneva, Switzerland) ISO 14729 stand-alone test protocol. The five specified compendial organisms, three bacteria (Staphylococcus aureus, Pseudomonas aeruginosa, and Serratia marcescens) and two fungi (Candida albicans and Fusarium solani) were incubated with each solution under standard conditions, after which microbes were recovered and quantified.Results: Each of the solutions evaluated met or exceeded the standard’s primary criteria (3-log reduction of bacteria and 1-log reduction of fungi) after incubation for the manufacturer-recommended soaking time, except for COMPLETE MPS, which achieved only 0.4 ± 0.1 average log reduction for C. albicans. However, differences in efficacy between the solutions were noted. Average log reduction across all microbes for Biotrue Hydration Plus (4.6 ± 0.1) was comparable to that for CLEAR CARE PLUS HPS (4.3 ± 0.1) and greater than those for OPTI-FREE puremoist (3.6 ± 0.1), OPTI-FREE Replenish (4.0 ± 0.2), ACUVUE RevitaLens (3.9 ± 0.03), and COMPLETE MPS (3.6 ± 0.1). Biotrue Hydration Plus was especially effective at reducing the population of C. albicans (4.2 ± 0.7-log reduction).Conclusion: Products marketed for planned replacement soft CL disinfection generally meet the ISO 14729 standard’s primary criteria for reducing populations of compendial organisms, with larger differences between solutions noted with C. albicans.Keywords: multi-purpose solution, MPS, hydrogen peroxide solution, HPS, disinfection, myristamidopropyl dimethylamine, MAPD, polyhexamethylene biguanide, PHMB, ISO 14729

Karl R VanDerMeid, Mirzi Grace Byrnes, Kimberly Millard, Catherine A Scheuer, Nitasha R Phatak, William Reindel Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USACorrespondence: Nitasha R Phatak, Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA, Tel +1 585-413-6397, Email nitasha.phatak@bausch.comPurpose: Contact lens (CL) wear challenges the balance of the ocular surface environment by increasing water evaporation and tear osmolarity. Maintaining ocular surface homeostasis during CL wear remains a goal of lens manufacturers and an important consideration for eye care professionals. The purpose of this study was to measure the metabolic activity and inflammatory responses of a transformed human corneal epithelial cell (THCEpiC) line under hyperosmotic conditions in the presence of CL packaging solutions.Methods: CL packaging solutions sampled from seven daily disposable silicone hydrogel CL blister packages were prepared at 25% and made hyperosmolar (400 mOsm/kg) with NaCl. THCEpiCs were incubated with each solution for 24 hr, after which cell culture supernatants were collected. THCEpiC metabolic activity was determined by an alamarBlue assay. Concentrations in cell culture supernatants of inflammatory cytokine (interleukin [IL]-6) and chemokine (IL-8), as well as monocyte chemoattractant protein-1 (MCP-1), were quantitated by specific enzyme-linked immunosorbent assays.Results: THCEpiC metabolic activity under hyperosmolar conditions decreased in the presence of somofilcon A and senofilcon A solutions (p=0.04 and 0.004, respectively), but no other solution (all p≥ 0.09). Concentrations of IL-6 increased in the presence of delefilcon A, somofilcon A, narafilcon A, and senofilcon A solutions (all p≤ 0.001), but no other solution (all p≥ 0.08), while those of IL-8 increased in the presence of all solutions (all p≤ 0.03) but kalifilcon A (p> 0.99), and those of MCP-1 increased in the presence of delefilcon A, verofilcon A, somofilcon A, and stenfilcon A solutions (all p< 0.0001), but no other solution (all p> 0.99).Conclusion: CL packaging solutions differ in their capacity to inhibit epithelial inflammation. THCEpiC inflammatory response was less in the presence of a CL packaging solution containing osmoprotectants than in solutions lacking osmoprotectants under moderately hyperosmolar conditions in vitro. Clinical studies are warranted to further substantiate the benefit of osmoprotectants.Keywords: contact lens, cornea, TFOS, hyperosmolarity, osmoprotection, homeostasis

Although it is increasingly accepted that young (e.g., [less than or equal to]30 years) stands originating from wildfire are considerably less flammable than older stands in the boreal forest of North America, the role of fuel availability and structure in this phenomenon has not been thoroughly investigated. As a regional study in a high-frequency fire regime, detailed wildfire fuel loading and structure were measured in 66 sites including both wetlands and uplands in the Boreal Plains landscape of Wood Buffalo National Park in northwestern Canada. Overall, a significant increase in total flammable biomass occurred in upland sites over 97 years, but this increase was not consistently observed in wetlands, except where there was dense tree cover. Fuel accumulation was highly moderated by canopy fuels, as surface fuels were relatively constant across differing site types and time since fire, averaging 0.4 kg * [m.sup.-2]. Significant but gradual canopy fuel accumulation was observed in moist conifer upland forests dominated by mature black spruce (Picea mariana (Mill.) B.S.P.) or white spruce (Picea glauca (Moench) Voss) over 100 years since fire. Outside of these mature moist conifer uplands, there was no difference in total fuel loading between other upland forests and across the gradient of treed to open wetlands. Key words: boreal, wildfire, wetlands, fuels, vegetation structure. Bien qu'il soit de plus en plus accepte que les jeunes (p. ex. [less than or equal to]30 ans) peuplements issus de feux sont beaucoup moins inflammables que les peuplements plus vieux dans la foret boreale de l'Amerique du Nord, le role que jouent la structure et la disponibilite des combustibles dans ce phenomene n'a pas ete etudie a fond. Dans le cadre d'une etude regionale sur le regime de feux a haute frequence, la structure et la charge des combustibles des feux ont ete mesurees en detail a 66 endroits, incluant tant des zones humides que bien drainees dans le paysage de plaines boreales du parc national Wood Buffalo dans le nord-ouest canadien. Dans l'ensemble, une augmentation importante de la biomasse inflammable totale est survenue dans les stations bien drainees apres 97 ans mais cette augmentation n'a pas systematiquement ete observee dans les zones humides, a l'exception des endroits oU le couvert arborescent etait dense. L'accumulation de combustibles etait fortement temperee par les combustibles dans le couvert forestier etant donne que les combustibles de surface etaient relativement constants parmi differents types de stations et temps ecoules depuis le feu, atteignant en moyenne 0,4 kg * [m.sup.-2]. Une accumulation importante mais graduelle de combustibles dans le couvert a ete observee dans les forets humides bien drainees de coniferes dominees par l'epinette noire (Picea mariana (Mill.) B.S.P.) ou l'epinette blanche (P. glauca (Moench) Voss) depuis plus de 100 ans apres un feu. A l'exception de ces stations humides bien drainees dominees par des coniferes matures, il n'y avait pas de difference dans la charge totale de combustibles entre d'autres forets bien drainees ainsi que le long du gradient allant de zones humides boisees a ouvertes. [Traduit par la Redaction] Mots-cles : boreal, feux de foret, zones humides, combustibles, structure de la vegetation., 1. Introduction Paleoecological reconstructions from tree rings (Wallenius et al. 2011) and charcoal and pollen (Larsen and MacDonald 1998) in boreal western Canada indicate a historic fire return interval that [...]

For most doctors, the lay staff is not only the biggest practice expense but also the most important factor in a successful practice. An office staff that's properly trained, managed, [...]