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Nanofabrication: remote etching of graphene on hBN is highly anisotropic Etching of graphite with hydrogen plasma gives rise to two distinct etching regimes, governed by the degree of direct plasma exposure. A team led by D. M. Zumbühl at the University of Basel investigated the interplay between graphite exposure to pure hydrogen plasma and the resulting etching features. When the sample surface is in direct contact with the plasma, a defect-rich etching regime occurs, resulting in the formation of etch pits with variable size. However, when graphite is away from the plasma source, a remote anisotropic etching takes place, giving rise to regular hexagons originating from localized defects and edges. In the latter regime, the authors found that in the case of graphene, isotropic etching is obtained using SiO2 as substrate, whereas highly anisotropic etching occurs when graphene is placed on hBN.

This paper describes the theoretical foundation of and explicit algorithms for a novel approach to morphology and anisotropy analysis of complex spatial structure using tensor-valued Minkowski functionals, the so-called Minkowski tensors . Minkowski tensors are generalizations of the well-known scalar Minkowski functionals and are explicitly sensitive to anisotropic aspects of morphology, relevant for example for elastic moduli or permeability of microstructured materials. Here we derive explicit linear-time algorithms to compute these tensorial measures for three-dimensional shapes. These apply to representations of any object that can be represented by a triangulation of its bounding surface; their application is illustrated for the polyhedral Voronoi cellular complexes of jammed sphere configurations and for triangulations of a biopolymer fibre network obtained by confocal microscopy. The paper further bridges the substantial notational and conceptual gap between the different but equivalent approaches to scalar or tensorial Minkowski functionals in mathematics and in physics, hence making the mathematical measure theoretic formalism more readily accessible for future application in the physical sciences.

Ultra short pulse Ti:sapphire lasers, crucial for most demanding applications, have traditionally been complex and costly due to their pump sources. GaN-based laser diodes offer new prospects for pumping, yet challenges persist in achieving sufficient Ti:sapphire output power and beam quality. We introduce what we believe to be a novel approach using pulsed blue laser diode pumping of a Ti:sapphire amplifier. Experimental setups with free-space output and fiber-delivered laser diodes are used to measure small signal gain (SSG) and thermal lensing. Results show the potential of fiber-delivered blue laser diodes, achieving an SSG >33% with reduced thermal load, paving the way for compact and low cost blue laser diode-pumped Ti:sapphire amplifiers at room temperature.

Objective: This study evaluates the 24-month follow-up for the NICHD Neonatal Research Network (NRN) Inositol for Retinopathy Trial., Study Design: Bayley Scales of Infants Development-III and a standardized neurosensory examination were performed in infants enrolled in the main trial. Moderate/severe NDI was defined as BSID-III Cognitive or Motor composite score <85, moderate or severe cerebral palsy, blindness, or hearing loss that prevents communication despite amplification were assessed., Results: Primary outcome was determined for 605/638 (95%). The mean gestational age was 25.8 ± 1.3 weeks and mean birthweight was 805 ± 192 g. Treatment group did not affect the risk for the composite outcome of death or survival with moderate/severe NDI (60% vs 56%, p = 0.40)., Conclusions: Treatment group did not affect the risk of death or survival with moderate/severe NDI. Despite early termination, this study represents the largest RCT of extremely preterm infants treated with myo-inositol with neurodevelopmental outcome data., (© 2021. This is a U.S. government work and not under copyright protection in the U.S.; foreign copyright protection may apply.)

Importance: Previous studies of myo-inositol in preterm infants with respiratory distress found reduced severity of retinopathy of prematurity (ROP) and less frequent ROP, death, and intraventricular hemorrhage. However, no large trials have tested its efficacy or safety., Objective: To test the adverse events and efficacy of myo-inositol to reduce type 1 ROP among infants younger than 28 weeks' gestational age., Design, Setting, and Participants: Randomized clinical trial included 638 infants younger than 28 weeks' gestational age enrolled from 18 neonatal intensive care centers throughout the United States from April 17, 2014, to September 4, 2015; final date of follow-up was February 12, 2016. The planned enrollment of 1760 participants would permit detection of an absolute reduction in death or type 1 ROP of 7% with 90% power. The trial was terminated early due to a statistically significantly higher mortality rate in the myo-inositol group., Interventions: A 40-mg/kg dose of myo-inositol was given every 12 hours (initially intravenously, then enterally when feeding; n = 317) or placebo (n = 321) for up to 10 weeks., Main Outcomes and Measures: Type 1 ROP or death before determination of ROP outcome was designated as unfavorable. The designated favorable outcome was survival without type 1 ROP., Results: Among 638 infants (mean, 26 weeks' gestational age; 50% male), 632 (99%) received the trial drug or placebo and 589 (92%) had a study outcome. Death or type 1 ROP occurred more often in the myo-inositol group vs the placebo group (29% vs 21%, respectively; adjusted risk difference, 7% [95% CI, 0%-13%]; adjusted relative risk, 1.41 [95% CI, 1.08-1.83], P = .01). All-cause death before 55 weeks' postmenstrual age occurred in 18% of the myo-inositol group and in 11% of the placebo group (adjusted risk difference, 6% [95% CI, 0%-11%]; adjusted relative risk, 1.66 [95% CI, 1.14-2.43], P = .007). The most common serious adverse events up to 7 days of receiving the ending dose were necrotizing enterocolitis (6% for myo-inositol vs 4% for placebo), poor perfusion or hypotension (7% vs 4%, respectively), intraventricular hemorrhage (10% vs 9%), systemic infection (16% vs 11%), and respiratory distress (15% vs 13%)., Conclusions and Relevance: Among premature infants younger than 28 weeks' gestational age, treatment with myo-inositol for up to 10 weeks did not reduce the risk of type 1 ROP or death vs placebo. These findings do not support the use of myo-inositol among premature infants; however, the early termination of the trial limits definitive conclusions.

Trace metal risk assessment and environmental quality standard definition require realistic models that quantify metal exposure and accumulation by biota. In the present study we propose a novel trait-based approach to predict whole body concentrations of metals in aquatic invertebrates from concentrations measured in different environmental compartments. Field data from a large riverine floodplain was used to calibrate and test the model. The prediction performance of the trait-based model was unbiased and uncertainty was below the twofold of measured concentrations for the four studied metals (Ni, Cu, Cd, Pb). The relative contribution of feeding, respiration and locomotion patterns as well as metal concentrations in three environmental compartments provided insights into the importance of different uptake pathways. The relation with the sediment (i.e., to what degree taxa live in or directly on the sediment) was shown to be the most important trait to predict metal accumulation. Overall, this study demonstrated the potential use of bioecological traits for the modeling of whole body metal concentrations of entire aquatic invertebrate communities., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Floodplain water bodies provide habitat to diversified ecological communities. Floodplains are also among the most impacted aquatic ecosystems. While the link between the lateral connectivity of floodplain sites to the main channel and their plant, fish and invertebrate communities has been well established, detailed information on chemical characteristics and particularly on trace metal spatial distribution and partitioning is scarce. The aim of this study was to examine the link between the lateral connectivity and physico-chemical variables, their trace metal concentrations and partitioning as well as the upstream-downstream gradient of these parameters. In connected and disconnected water bodies of the Rhône River upstream and downstream of the city of Lyon, we measured major ions, dissolved organic carbon, trace metal concentrations (Al, Cr, Ni, Cu, Zn, Cd, Pb and U) in water, suspended particulate matter (SPM) and sediment. The results revealed a clear difference between connected and disconnected water bodies. pH, SPM, Na + , and NO 3 - concentrations were lower in disconnected sites while conductivity, DOC, Ca 2+ and Mg 2+ were higher. Conductivity and a part of the major ion concentrations increased in the downstream sections. Trace metal concentrations and partitioning varied between connected and disconnected sites. In the dissolved fraction, trace metal concentrations were higher in connected sites. In the surface sediment, concentrations were higher in disconnected sites for the majority of metals. The upstream-downstream gradient was less important than the connected-disconnected gradient. Only three metals in the dissolved fraction (Cu, Cd and Pb) showed a clear increase in downstream sections. Overall, the study shows that the functioning of floodplains produces strong spatial patterns concerning the concentrations and partitioning of trace metals. These findings improve our understanding of trace metal biogeochemistry in floodplains and have important applications for floodplain restoration projects., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Freshwater biofilms can be useful indicators of water quality and offer the possibility to assess contaminant effects at the community level. The present field study examines the effects of chlor-alkali plant effluents on the community composition of biofilms grown in the Olt River (Romania) reservoirs. The relationship between ambient water quality variables and community composition alterations was explored. Amplicon sequencing revealed a significant modification of the composition of microalgal, bacterial and fungal communities in the biofilms collected in the impacted reservoirs in comparison with those living in the uncontaminated control reservoir. The abundance corrected Simpson index showed lower richness and diversity in biofilms collected in the impacted reservoirs than in the control reservoir. The biofilm bacterial communities of the impacted reservoirs were characterized by the contaminant-tolerant Cyanobacteria and Bacteroidetes, whereas microalgal communities were predominantly composed of Bacillariophyta and fungal communities of Lecanoromycetes and Paraglomycetes. A principal component analysis revealed that major contaminants present in the waste water of the chlor-alkali production plant, i.e. Na + , Ca 2+ , Cl - and Hg, were correlated with the alteration of biofilm community composition in the impacted reservoirs. However, the biofilm composition was also influenced by water quality variables such as NO 3 - , SO 4 2- , DOC and Zn from unknown sources. The results of the present study imply that, even when below the environmental quality standards, typical contaminants of chlor-alkali plant releases may affect biofilm composition and that their impacts on the microbial biodiversity might be currently overlooked.

Objective: To describe baseline characteristics, initial postoperative refractive errors, operative complications, and magnitude of the intraocular lens (IOL) prediction error for refractive outcome in children undergoing lensectomy largely in North America., Design: Prospective registry study of children from birth to <13 years of age who underwent lensectomy for any reason within 45 days preceding enrollment., Participants: Total of 1266 eyes of 994 children; 49% female and 59% white., Methods: Measurement of refractive error, axial length, and complete ophthalmic examination., Main Outcome Measures: Eye and systemic associated conditions, IOL style, refractive error, pseudophakic refraction prediction error, operative and perioperative complications., Results: Mean age at first eligible lens surgery was 4.2 years; 337 (34%) were <1 year of age. Unilateral surgery was performed in 584 children (59%). Additional ocular abnormalities were noted in 301 eyes (24%). An IOL was placed in 35 of 460 eyes (8%) when surgery was performed before 1 year of age, in 70 of 90 eyes (78%) from 1 to <2 years of age, and in 645 of 716 eyes (90%) from 2 to <13 years of age. The odds of IOL implantation were greater in children ≥2 years of age than in those <2 years of age (odds ratio = 29.1; P < 0.001; 95% confidence interval: 19.6-43.3). Intraoperative complications were reported for 69 eyes (5%), with the most common being unplanned posterior capsule rupture in 14 eyes, 10 of which had an IOL placed. Prediction error of the implanted IOL was <1.00 diopter in 54% of eyes, but >2.00 diopters in 15% of eyes., Conclusions: Lensectomy surgery was performed throughout childhood, with about two-thirds of cases performed after 1 year of age. Initial surgery seemed safe, with a low complication rate. IOL placement was nearly universal in children 2 years of age and older. The immediate postoperative refraction was within 1 diopter of the target for about one-half of eyes., Competing Interests: No conflicting relationships exist for any author., (Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose of Review: Surgical treatment has been the accepted mode of treatment for infantile esotropia for decades. The present review of recent literature evaluates the current standing of: type of surgery performed and best timing of surgery to achieve optimal results., Recent Findings: Recent studies suggest that early surgical intervention is of benefit by improving the probability of developing stereopsis. A significant advantage of the type of surgical intervention has yet to be demonstrated by the current studies. Botulinum toxin continues to be used for treatment of infantile esotropia, although it has not been shown to be a superior treatment., Summary: Although many theories exist, the true cause of infantile esotropia remains unknown. The literature suggests that treatment before age 2 and perhaps even earlier improves the potential for binocular vision. After significant review of literature, it is clear that surgery is the treatment of choice for infantile esotropia but no method has a clear advantage. Efforts to define the best surgical procedure and timing of surgery through prospective, randomized multicenter trials are warranted.

Background: Resistance to microtubule-stabilizing agents is a major hurdle for successful cancer therapy. We investigated combined treatment of microtubule-stabilizing agents (MSAs) with inhibitors of angiogenesis to overcome MSA resistance., Methods: Treatment regimens of clinically relevant MSAs (patupilone and paclitaxel) and antiangiogenic agents (everolimus and bevacizumab) were investigated in genetically defined MSA-resistant lung (A549EpoB40) and colon adenocarcinoma (SW480) tumor xenografts in nude mice (CD1-Foxn1, ICRnu; 5-14 per group). Tumor growth delays were calculated by Kaplan-Meier analysis with Holm-Sidak tests. All statistical tests were two-sided., Results: Inhibition of mTOR-kinase by everolimus only minimally reduced the proliferative activity of β tubulin-mutated lung adenocarcinoma cells alone and in combination with the MSA patupilone, but everolimus inhibited expression and secretion of vascular endothelial growth factor (VEGF) from these cells. mTOR-kinase inhibition strongly sensitized tumor xenografts derived from these otherwise MSA-resistant tumor cells to patupilone. Tumors treated with the combined modality of everolimus and patupilone had statistically significantly reduced tumor volume and stronger tumor growth delay (16.2 ± 1.01 days) than control- (7.7 ± 0.3 days, P = .004), patupilone- (10 ± 0.97 days, P = .009), and everolimus-treated (10.6 ± 1.4 days, P = .014) tumors. A combined treatment modality with bevacizumab also resensitized this MSA-refractory tumor model to patupilone. Treatment combination also strongly reduced microvessel density, corroborating the relevance of VEGF targeting for the known antivasculature-directed potency of MSA alone in MSA-sensitive tumor models. Resensitization to MSAs was also probed in P glycoprotein-overexpressing SW480-derived tumor xenografts. Different bevacizumab regimens also sensitized this otherwise-resistant tumor model to clinically relevant MSA paclitaxel., Conclusions: A treatment combination of MSAs with antiangiogenic agents is potent to overcome tumor cell-linked MSA resistance and should be considered as strategy for MSA-refractory tumor entities., (© The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Single- and multilayer graphene and highly ordered pyrolytic graphite (HOPG) were exposed to a pure hydrogen low-temperature plasma (LTP). Characterizations include various experimental techniques such as photoelectron spectroscopy, Raman spectroscopy and scanning probe microscopy. Our photoemission measurement shows that hydrogen LTP exposed HOPG has a diamond-like valence-band structure, which suggests double-sided hydrogenation. With the scanning tunneling microscopy technique, various atomic-scale charge-density patterns were observed, which may be associated with different C-H conformers. Hydrogen-LTP-exposed graphene on SiO(2) has a Raman spectrum in which the D peak to G peak ratio is over 4, associated with hydrogenation on both sides. A very low defect density was observed in the scanning probe microscopy measurements, which enables a reverse transformation to graphene. Hydrogen-LTP-exposed HOPG possesses a high thermal stability, and therefore, this transformation requires annealing at over 1000 °C.

Tumor hypoxia is one of the most important parameters that determines treatment sensitivity and is mainly due to insufficient tumor angiogenesis. However, the local oxygen concentration in a tumor can also be shifted in response to different treatment modalities such as cytotoxic agents or ionizing radiation. Thus, combined treatment modalities including microtubule stabilizing agents could create an additional challenge for an effective treatment response due to treatment-induced shifts in tumor oxygenation. Tumor hypoxia was probed over a prolonged observation period in response to treatment with different cytotoxic agents, using a non-invasive bioluminescent ODD-Luc reporter system, in which part of the oxygen-dependent degradation (ODD) domain of HIF-1α is fused to luciferase. As demonstrated in vitro, this system not only detects hypoxia at an ambient oxygen concentration of 1% O(2), but also discriminates low oxygen concentrations in the range from 0.2 to 1% O(2). Treatment of A549 lung adenocarcinoma-derived tumor xenografts with the microtubule stabilizing agent patupilone resulted in a prolonged increase in tumor hypoxia, which could be used as marker for its antitumoral treatment response, while irradiation did not induce detectable changes in tumor hypoxia. Furthermore, despite patupilone-induced hypoxia, the potency of ionizing radiation (IR) was not reduced as part of a concomitant or adjuvant combined treatment modality.

Predicting physical properties of materials with spatially complex structures is one of the most challenging problems in material science. One key to a better understanding of such materials is the geometric characterization of their spatial structure. Minkowski tensors are tensorial shape indices that allow quantitative characterization of the anisotropy of complex materials and are particularly well suited for developing structure-property relationships for tensor-valued or orientation-dependent physical properties. They are fundamental shape indices, in some sense being the simplest generalization of the concepts of volume, surface and integral curvatures to tensor-valued quantities. Minkowski tensors are based on a solid mathematical foundation provided by integral and stochastic geometry, and are endowed with strong robustness and completeness theorems. The versatile definition of Minkowski tensors applies widely to different types of morphologies, including ordered and disordered structures. Fast linear-time algorithms are available for their computation. This article provides a practical overview of the different uses of Minkowski tensors to extract quantitative physically-relevant spatial structure information from experimental and simulated data, both in 2D and 3D. Applications are presented that quantify (a) alignment of co-polymer films by an electric field imaged by surface force microscopy; (b) local cell anisotropy of spherical bead pack models for granular matter and of closed-cell liquid foam models; (c) surface orientation in open-cell solid foams studied by X-ray tomography; and (d) defect densities and locations in molecular dynamics simulations of crystalline copper., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The authors describe the clinical presentations and ophthalmic findings of two patients with juvenile dermatomyositis. The results of their dilated eye examinations proved to influence the treatment of the disease process because retinal pathology was used as a factor to escalate the degree of anti-inflammatory therapy. Therefore, an initial ophthalmic examination may be considered in patients with new-onset juvenile dermatomyositis., (Copyright 2010, SLACK Incorporated.)

Purpose of Review: The technological advancement of intraocular lenses (IOLs) in recent years has increased their use in the pediatric population. This has led to the use of IOLs in children in whom they would not have been considered in the past. Yet, the majority of the literature looking at the use of specialty IOLs is in the adult literature. This review will look at the use of IOLs in special circumstances as reported in the pediatric population., Recent Findings: A Medline search of the use of IOLs in children reveals 27 articles published in the past year. The data available on the use of IOLs in special circumstances in children are significantly less. This paper will review the safety and efficacy of the use of IOLs in children with uveitis. Options available to treat aphakia in children with inadequate support for posterior chamber IOLs are explored. Finally, the role of using multifocal and other specialty IOLs is reviewed., Summary: The use of IOL implantation in the pediatric population is evolving. There is much promise in using IOLs in specialty circumstances, but caution should be applied when using these new technologies in the pediatric population. Efforts must be made to study these areas within the pediatric population.

A double quantum dot is formed in a graphene nanoribbon device using three top gates. These gates independently change the number of electrons on each dot and tune the interdot coupling. Transport through excited states is observed in the weakly coupled double dot regime. We extract from the measurements all relevant capacitances of the double dot system, as well as the quantized level spacing.

Purpose: We sought to assess the success of amblyopia treatment in patients with small posterior lens opacities as well as the factors associated with a good visual outcome., Methods: This was a retrospective study of patients with posterior lens opacities that initially were thought to be too small in size to warrant cataract surgery. The following variables were examined: cataract type, location, diameter, persistent hyaloid vessel, anisometropia, strabismus, and age of detection. Success of treatment of amblyopia was defined as improvement by at least 0.3 logMAR units. Good visual outcome was defined as 20/40 or better. Amblyopia was treated by glasses, patching, and/or atropine. Patients who failed with conservative treatment or had an increase in cataract size underwent surgery., Results: Forty-eight (91%) of 53 eyes were amblyopic. Thirty amblyopic eyes had pre- and post-treatment Snellen acuities. Twenty (67%) had their visual acuity (VA) improved by 0.3 logMAR units or greater. None of the measured variables were associated with successful amblyopia treatment. Twenty-five (49%) of 51 patients had a final VA of 20/40 or better. The only variable associated with good visual outcome was cataract type: 18 of 25 (72%) posterior subcapsular cataract and 6 of 23 (32%) posterior lenticonus eyes achieved VA of 20/40 or better (P = 0.008). Six patients who went on to have cataract surgery experienced a larger improvement in BCVA (4.50 logMar units +/- 2.52 lines) compared with patients treated without cataract surgery (2.36 logMar units +/- 3.11 lines)., Discussion: Amblyopia treatment was successful in most cases. A small group of patients who underwent cataract surgery experienced a greater VA improvement; however, it was not statistically significant. Further studies are needed to determine which patients would benefit from cataract surgery.

Aspergillus fumigatus phytase has previously been identified as a phytase with a series of favourable properties that may be relevant in animal and human nutrition, both for maximising phytic acid degradation and for increasing mineral and amino acid availability. To study the natural variability in amino acid sequence and its impact on the catalytic properties of the enzyme, we cloned and overexpressed the phytase genes and proteins from six new purported A. fumigatus isolates. Five of these phytases displayed < or= 2 amino acid substitutions and had virtually identical stability and catalytic properties when compared with the previously described A. fumigatus ATCC 13073 phytase. In contrast, the phytase from isolate ATCC 32239 ( Sartorya fumigata, the anamorph of which was identified as A. fumigatus) was more divergent (only 86% amino acid sequence identity), had a higher specific activity with phytic acid, and displayed distinct differences in substrate specificity and pH-activity profile. Finally, comparative experiments confirmed the favourable stability and catalytic properties of A. fumigatus phytase.

Study Objective: We compare percentage of healing, comfort, and complications in children with corneal abrasions treated with an eye patch versus no eye patch., Methods: We performed a randomized clinical trial of patients aged 3 to 17 years who were diagnosed with isolated corneal abrasion. Patients were randomly assigned to an eye patch or no patch group. Abrasion size was documented with digital photographs and/or an eye template diagram at presentation and at 20- to 24-hour follow-up examination. A reviewer masked to treatment group determined percent healing by measuring presentation and follow-up abrasion sizes on the photographs/template. At follow-up, interference with activities of daily living (ADL) was measured with a visual analog scale and the number of pain medication doses taken since presentation was recorded., Results: A total of 37 patients were enrolled: 17 with an eye patch and 18 with no eye patch. The mean patient age was 10 years, and two thirds of the patients were male. The majority (86%) of patients had 95% or more healing at follow-up, and there was no significant difference in percent healing between the 2 groups, even when adjusted for age and initial abrasion size (95% confidence interval [CI] for the difference in means -11 to 8 and -13 to 5, respectively). There was no difference between groups for number of pain medication doses required. Among measurements of interference with ADL, only the difficulty walking score was found to be significantly different between groups (patch mean 1.7 cm [SD 2.1 cm] versus no patch mean 0.3 cm [SD 0.7 cm]; 95% CI for the difference in means 0.3 to 2.5)., Conclusion: This study suggests that eye patching in children with corneal abrasions makes no difference in the rate of healing. There was no difference in discomfort and interference with ADL, other than greater difficulty walking in the patch group, and there were no complications in either group.

Ultraviolet B (UVB, 290-320 nm) radiation initiates in vivo a dose- and wavelength-dependent down regulation of cell-mediated immunity. An action spectrum for UV-induced immunosuppression indicated that the photoreceptor for this effect is urocanic acid (UCA), which undergoes a trans to cis isomerization in the stratum corneum on UV exposure. An accumulation of evidence has supported this conclusion. However, evidence has also been presented that formation of thymine dimers in DNA is responsible for initiation of UV-induced immunosuppression. Because photobinding of UCA to DNA in vitro forming cyclobutane-type adducts has been shown, we sought to resolve this dilemma by investigating if UCA photobinds to DNA in vivo. The [14C]cis-UCA, [14C]trans-UCA or [3H]8-MOP (8-methoxypsoralen) was applied topically to BALB/c mice that were then irradiated with a dose of UV previously shown to cause systemic suppression of contact hypersensitivity. The DNA was prepared from epidermal cells by phenol extraction immediately after in vivo irradiation and bound radioactivity determined. Although photobinding of [3H]8-MOP was readily demonstrable under these conditions (0.9 nmol/mg DNA), no significant binding of either isomer of UCA to DNA (between 1.2 x 10(-3) and 2.1 x 10(-3) ng/mg DNA) could be detected. Uptake studies in keratinocytes prepared from epidermis of untreated animals indicated that [3H]8-MOP was taken up with a rate constant of 4.2 x 10(-3) pmol/s/mg protein/mumol/L. In contrast, uptake of [14C]cis-UCA was not statistically significant from zero and uptake of [14C]trans-UCA was negligible (0.8 x 10(-3) +/- 0.08 x 10(-3) pmol/s/mg protein/mumol/L). There was no significant difference between uptake of UCA isomers, but uptake of [3H]8-MOP was significantly greater than that of either UCA isomer (P < 0.01). These studies indicate that the photobinding of UCA to DNA does not play a role in UV-induced immunosuppression.

The Gram-negative bacterium Flavobacterium sp. strain R1534 is a natural producer of zeaxanthin. A 14 kb genomic DNA fragment of this organism has been cloned and a 5.1 kb piece containing the carotenoid biosynthesis genes sequenced. The carotenoid biosynthesis cluster consists of five genes arranged in at least two operons. The five genes are necessary and sufficient for the synthesis of zeaxanthin. The encoded proteins have significant homology to the crtE, crtB, crtY, crtI and crtZ gene products of other carotenogenic organisms. Biochemical assignment of the individual gene products was done by HPLC analysis of the carotenoid accumulation in Escherichia coli host strains transformed with plasmids carrying deletions of the Flavobacterium sp. strain R1534 carotenoid biosynthesis cluster.

A rabbit serum raised against Eimeria tenella merozoites was used to screen a lambda gt11 cDNA library made from merozoite mRNA of E. tenella. The insert of the phage clone lambda Mz 5-7 revealed an open reading frame consisting of 945 nucleotides, encoding a 33-kDa protein. This size is consistent with the size of a protein translated in vitro from merozoite mRNA and immunoprecipitated with monospecific anti-Mzp 5-7 antibodies. A smaller protein of 24 kDa, located on the surface of the parasite, also reacted with the monospecific antiserum and is the potential processed form of the Mzp 5-7. Furthermore, a recombinant vaccinia virus expressing the Mzp 5-7 antigen was constructed and used to immunize chickens.