Long-term climatic stability drives accumulation and maintenance of divergent freshwater fish lineages in a temperate biodiversity hotspot.

Anthropogenic climate change is forecast to drive regional climate disruption and instability across the globe. These impacts are likely to be exacerbated within biodiversity hotspots, both due to the greater potential for species loss but also to the possibility that endemic lineages might not have experienced significant climatic variation in the past, limiting their evolutionary potential to respond to rapid climate change. We assessed the role of climatic stability on the accumulation and persistence of lineages in an obligate freshwater fish group endemic to the southwest Western Australia (SWWA) biodiversity hotspot. Using 19,426 genomic (ddRAD-seq) markers and species distribution modelling, we explored the phylogeographic history of western (Nannoperca vittata) and little (Nannoperca pygmaea) pygmy perches, assessing population divergence and phylogenetic relationships, delimiting species and estimating changes in species distributions from the Pliocene to 2100. We identified two deep phylogroups comprising three divergent clusters, which showed no historical connectivity since the Pliocene. We conservatively suggest these represent three isolated species with additional intraspecific structure within one widespread species. All lineages showed long-term patterns of isolation and persistence owing to climatic stability but with significant range contractions likely under future climate change. Our results highlighted the role of climatic stability in allowing the persistence of isolated lineages in the SWWA. This biodiversity hotspot is under compounding threat from ongoing climate change and habitat modification, which may further threaten previously undetected cryptic diversity across the region.

Net design for selective control of the "plague minnow" Gambusia holbrooki that minimises impact on native Australian fishes.

Gambusia holbrooki is one of the world's most environmentally damaging introduced species, being notoriously difficult to control once established. A composite double-winged fyke net comprising four vertically stacked compartments was developed to determine the potential to control G. holbrooki, while reducing negative interactions of this aggressive species with small threatened fishes. The stacked fyke net captured three times as many G. holbrooki as a conventional fyke net while maintaining consistent catches of native fishes relative to that from a conventional fyke net, and detected species-specific vertical distributions. This stratified net design represents a valuable management option for controlling this agonistic species or for limiting antagonistic interactions between G. holbrooki and native species during typical fyke sampling of native ecosystems.

Divergent field metabolic rates highlight the challenges of increasing temperatures and energy limitation in aquatic ectotherms.

Environments where extreme temperatures and low productivity occur introduce energetically challenging circumstances that may be exacerbated by climate change. Despite the strong link between metabolism and temperature in ectotherms, there is a paucity of data regarding how the metabolic ecology of species affects growth and fitness under such circumstances. Here, we integrated data describing field metabolic rates and body condition of two sympatric species of ectotherms with divergent lifestyles, the benthic freshwater (or largetooth) sawfish (Pristis pristis) and the epipelagic bull shark (Carcharhinus leucas) occurring in the Fitzroy River, Western Australia, to test the implications of their differing metabolic ecologies for vulnerability to rising temperatures. Over a temperature range of 18-34 °C, sawfish had lower field metabolic rates (63-187 mg O2 kg-0.86 h-1) and lower temperature sensitivity of metabolic rates [activation energy (EA) = 0.35 eV] than bull sharks (187-506 mg O2 kg-0.86 h-1; EA = 0.48 eV). Both species lost body mass throughout the dry season, although bull sharks significantly more (0.17% mass loss day-1) than sawfish (0.07% mass loss day-1). Subsequent bioenergetics modelling showed that under future climate change scenarios, both species would reach potentially lethal levels of mass loss during dry season periods before the end of the century. These results suggest that ectotherms with low metabolic rates may be better suited to extreme environmental conditions, and that even small increases in temperature due to climate change could have substantial impacts on the ability of ectotherms to grow and survive in harsh conditions, including high temperatures and energy-limiting circumstances.

Cryptic habitat use of white sharks in kelp forest revealed by animal-borne video.

Traditional forms of marine wildlife research are often restricted to coarse telemetry or surface-based observations, limiting information on fine-scale behaviours such as predator-prey events and interactions with habitat features. We use contemporary animal-attached cameras with motion sensing dataloggers, to reveal novel behaviours by white sharks, Carcharodon carcharias, within areas of kelp forest in South Africa. All white sharks tagged in this study spent time adjacent to kelp forests, with several moving throughout densely kelp-covered areas, navigating through channels and pushing directly through stipes and fronds. We found that activity and turning rates significantly increased within kelp forest. Over 28 h of video data revealed that white shark encounters with Cape fur seals, Arctocephalus pusillus pusillus, occurred exclusively within kelp forests, with seals displaying predator evasion behaviour during those encounters. Uniquely, we reveal the use of kelp forest habitat by white sharks, previously assumed inaccessible to these large predators.

Serum and macular response to carotenoid-enriched egg supplementation in human subjects: the Egg Xanthophyll Intervention clinical Trial (EXIT).

The macular carotenoids lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) accumulate at the macula, where they are collectively referred to as macular pigment (MP). Augmentation of this pigment, typically achieved through diet and supplementation, enhances visual function and protects against progression of age-related macular degeneration. However, it is known that eggs are a rich dietary source of L and Z, in a highly bioavailable matrix. In this single-blind placebo-controlled study, L- and MZ-enriched eggs and control non-enriched eggs were fed to human subjects (mean age 41 and 35 years, respectively) over an 8-week period, and outcome measures included MP, visual function and serum concentrations of carotenoids and cholesterol. Serum carotenoid concentrations increased significantly in control and enriched egg groups, but to a significantly greater extent in the enriched egg group (P<0·001 for L, Z and MZ). There was no significant increase in MP in either study group post intervention, and we saw no significant improvement in visual performance in either group. Total cholesterol increased significantly in each group, but it did not exceed the upper limit of the normative range (6·5 mmol/l). Therefore, carotenoid-enriched eggs may represent an effective dietary source of L, Z and MZ, reflected in significantly raised serum concentrations of these carotenoids, and consequentially improved bioavailability for capture by target tissues. However, benefits in terms of MP augmentation and /or improved visual performance were not realised over the 8-week study period, and a study of greater duration will be required to address these questions.

Identifying Predictors of Anti-VEGF Treatment Response in Patients with Neovascular Age-Related Macular Degeneration through Discriminant and Principal Component Analysis.

OBJECTIVE: AURA was an observational study that monitored visual acuity outcomes following ranibizumab use in neovascular age-related macular degeneration patients over 2 years. The aim of this analysis was to identify factors that were predictive of visual acuity outcomes in AURA. METHODS: The correlation between the baseline characteristics, the use of resources and the visual acuity outcomes in AURA was explored using principal component analysis (PCA) and partial least-squares-discriminant analysis (PLS-DA). The response variables analysed were mean change in visual acuity over 2 years (analysed via PCA) and no decline in visual acuity at 2 years compared with baseline (analysed via PLS-DA). RESULTS: The AURA dataset comprised 2,227 patients and 132 variables. Using PCA and PLS-DA, we found that the number of ranibizumab injections, clinic and monitoring visits, number of optical coherence tomography scans and ophthalmoscopies correlated with a change in visual acuity at Years 1 and 2, and are therefore key drivers of treatment success. CONCLUSION: This is a novel approach to graphically explore relationships between multiple correlated covariates and outcomes in real-life ophthalmology studies. It identified a number of variables that are positively linked with treatment outcomes.

Phenotypes of orthostatic blood pressure behaviour and association with visual acuity.

BACKGROUND: Manifestations of neurocardiovascular instability (NCVI), including orthostatic hypotension (OH) orthostatic hypertension (OHTN) and impaired blood pressure variability (BPV), have been associated with cardiovascular (CV) events. The eye is highly vascular and we propose an ideal target end organ to investigate pathological implications of NCVI. OBJECTIVE: To identify and define clinically applicable phenotypes of orthostatic blood pressure (BP) behaviour, analogous to OH, OHTN, and orthostatic BPV and to investigate their relationship to vision. METHODS: Wave one data from the Irish Longitudinal Study on Ageing (TILDA) were used. Orthostatic BP (OBP) phenotypes were identified and defined from beat-to-beat BP data, measured by digital photoplethysmography during an active stand (AS) lasting 110 s (s). Visual acuity (VA) was assessed using the Early Treatment Diabetic Retinopathy Study (EDTRS) LogMAR chart. The relationship between OBP phenotypes and VA in 4355 adults aged ≥50 years was investigated through multivariate linear regression models. RESULTS: There was a wide fluctuation in the prevalence of OH and OHTN up to 20 s after standing. After 30 s, four distinct OBP phenotypes were identified: in 70 % BP stabilised to within 20/10 mmHg of baseline BP, 4 % had persistent OH, 2 % had persistent OHTN and 25 % had exaggerated orthostatic blood pressure variability BPV. Systolic BPV was associated with worse VA (P = 0.02) as was diastolic BPV (P = 0.03), following adjustment for demographics, health behaviours, self-report eye diseases and diabetes, uncorrected refractive error, objective hypertension and antihypertensives. CONCLUSIONS: The hypothesis that NCVI may independently modulate CV risk is supported the independent association of exaggerated BPV and worse VA.

Macular response to supplementation with differing xanthophyll formulations in subjects with and without age-related macular degeneration.

PURPOSE: Our aim was to investigate the macular response to three different supplements containing lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ) in normal subjects and those with age-related macular degeneration (AMD). MATERIALS AND METHODS: Macular pigment optical density (MPOD) and serum xanthophyll concentrations were measured in normal (n = 31) and AMD subjects (n = 32), randomly assigned to: group 1 (20 mg L, 2 mg Z, 0.3 mg MZ), group 2 (10 mg L, 2 mg Z, 10 mg MZ) or group 3 (3 mg L, 2 mg Z, 17 mg MZ). MPOD was measured at baseline, 2, 4, 6 and 8 weeks and at 0.25°, 0.5°, 1.0° and 1.75° of eccentricity using customised heterochromatic flicker photometry and serum xanthophylls by HPLC. RESULTS: MPOD increased significantly at all eccentricities in each group (p < 0.05), except at 1.75° in group 3 (p = 0.242). There was no difference in MPOD measurements between AMD and normal subjects, except for group 2, where AMD subjects exhibited a greater response at 1.75° (p = 0.012). Final serum concentrations of MZ were positively and significantly related to final MPOD values at each eccentricity in all subjects. Targeted analysis of those subjects receiving the MZ-containing supplements exhibited stronger relationships between serum MZ concentrations and MPOD at 0.25° in group 3 than group 2; in group 2 all associations were positive, but only significant at 1.75°. CONCLUSIONS: Serum concentrations of MZ were strongly correlated with MPOD after 8 weeks of supplementation with the group 3 formulation, but the inclusion of L in the group 2 formulation may result in greater MPOD augmentation across the spatial profile.

Determinants of patient satisfaction and function related to vision following cataract surgery in eyes with no visually consequential ocular co-morbidity.

PURPOSE: To investigate subjectively reported outcomes following cataract surgery and the relationships between such outcomes in the context of falling thresholds for cataract surgery. SETTING: Large, private, non-refractive cataract practice, Institute of Eye Surgery, Whitfield Clinic, Waterford, Ireland METHODS: Pre-operative, intra-operative and post-operative data of 2552 eyes undergoing phacoemulsification and implantation of the Tecnis(R) ZCB00 1-piece intraocular lens (IOL) by a single surgeon between July 2009 and October 2013 was analysed. Patients without visually consequential ocular co-morbidity completed two validated questionnaires, designed to assess subjectively perceived visual functioning and identify symptoms of dysphotopsia following cataract surgery. RESULTS: 54.8 % of questionnaire respondents were entirely satisfied (satisfaction 10/10) post-operatively, with 83.7 % reporting satisfaction of ≥7/10. Satisfaction was positively associated with patient age and negatively associated with spectacle dependence, dysphotopsia, and function related to vision (NEI VF-11) score. The mean (±standard deviation[SD]) dysphotopsia score was 1.36 (±1.9; scale 0-10), with 40 % of respondents reporting no dysphotopsia symptoms and 9.8 % reporting clinically meaningful dysphotopsia. The mean (±SD) National Eye Institute visual function-11 (NEI VF-11) score was 0.33 (±0.53; scale 0-4) and reduced function related to vision was associated with increasing severity of dysphotopsia symptoms. When linear regression was applied, 17.5 % of the variation in functionality was attributable to symptoms of dysphotopsia. CONCLUSION: Dysphotopsia is an important determinant of a patient having difficulty with vision-related tasks following cataract surgery, and patient satisfaction is positively associated with patient age and negatively associated with spectacle in dependence, dysphotopsia and function related to the vision (NEI VF-11) score.

Implications of climate change for potamodromous fishes.

There is little understanding of how climate change will impact potamodromous freshwater fishes. Since the mid 1970s, a decline in annual rainfall in south-western Australia (a globally recognized biodiversity hotspot) has resulted in the rivers of the region undergoing severe reductions in surface flows (ca. 50%). There is universal agreement amongst Global Climate Models that rainfall will continue to decline in this region. Limited data are available on the movement patterns of the endemic freshwater fishes of south-western Australia or on the relationship between their life histories and hydrology. We used this region as a model to determine how dramatic hydrological change may impact potamodromous freshwater fishes. Migration patterns of fishes in the largest river in south-western Australia were quantified over a 4 year period and were related to a number of key environmental variables including discharge, temperature, pH, conductivity and dissolved oxygen. Most of the endemic freshwater fishes were potamodromous, displaying lateral seasonal spawning migrations from the main channel into tributaries, and there were significant temporal differences in movement patterns between species. Using a model averaging approach, amount of discharge was clearly the best predictor of upstream and downstream movement for most species. Given past and projected reductions in surface flow and groundwater, the findings have major implications for future recruitment rates and population viabilities of potamodromous fishes. Freshwater ecosystems in drying climatic regions can only be managed effectively if such hydro-ecological relationships are considered. Proactive management and addressing existing anthropogenic stressors on aquatic ecosystems associated with the development of surface and groundwater resources and land use is required to increase the resistance and resilience of potamodromous fishes to ongoing flow reductions.

Proteomics in uveal melanoma.

Uveal melanoma is the most common primary intraocular malignancy in adults, with an incidence of 5-7 per million per year. It is associated with the development of metastasis in about 50% of cases, and 40% of patients with uveal melanoma die of metastatic disease despite successful treatment of the primary tumour. The survival rates at 5, 10 and 15 years are 65%, 50% and 45% respectively. Unlike progress made in many other areas of cancer, uveal melanoma is still poorly understood and survival rates have remained similar over the past 25 years. Recently, advances made in molecular genetics have improved our understanding of this disease and stratification of patients into low risk and high risk for developing metastasis. However, only a limited number of studies have been performed using proteomic methods. This review will give an overview of various proteomic technologies currently employed in life sciences research, and discuss proteomic studies of uveal melanoma.

Supplementation with three different macular carotenoid formulations in patients with early age-related macular degeneration.

PURPOSE: To investigate the impact of three different macular carotenoid formulations on macular pigment optical density and visual performance in subjects with early age-related macular degeneration. METHODS: Fifty-two subjects were supplemented and followed for 12 months, 17 of them were in intervention Group 1 (20 mg/day lutein and 2 mg/day zeaxanthin); 21 in Group 2 (10 mg/day meso-zeaxanthin, 10 mg/day lutein, and 2 mg/day zeaxanthin); and 14 in Group 3 (17 mg/day meso-zeaxanthin, 3 mg/day lutein, and 2 mg/day zeaxanthin). The macular pigment optical density was measured using customized heterochromatic flicker photometry, and visual function was assessed using corrected distance visual acuity and by letter contrast sensitivity. RESULTS: A statistically significant increase in the macular pigment optical density was observed at all measured eccentricities in Group 2 (P ≤ 0.005) and in Group 3 (P < 0.05, for all), but only at 1.75° in Group 1 (P = 0.018). Statistically significant (P < 0.05) improvements in letter contrast sensitivity were seen at all spatial frequencies (except 1.2 cycles per degree) in Group 3, and at low spatial frequencies in Groups 1 and 2. CONCLUSION: Augmentation of the macular pigment optical density across its spatial profile and enhancements in contrast sensitivity were best achieved after supplementation with a formulation containing high doses of meso-zeaxanthin in combination with lutein and zeaxanthin.

Secondary outcomes in a clinical trial of carotenoids with coantioxidants versus placebo in early age-related macular degeneration.

PURPOSE: To report the secondary outcomes in the Carotenoids with Coantioxidants in Age-Related Maculopathy trial. DESIGN: Randomized double-masked placebo-controlled clinical trial (registered as ISRCTN 94557601). PARTICIPANTS: Participants included 433 adults 55 years of age or older with early age-related macular degeneration (AMD) in 1 eye and late-stage disease in the fellow eye (group 1) or early AMD in both eyes (group 2). INTERVENTION: An oral preparation containing lutein (L), zeaxanthin (Z), vitamin C, vitamin E, copper, and zinc or placebo. Best-corrected visual acuity (BCVA), contrast sensitivity (CS), Raman spectroscopy, stereoscopic colour fundus photography, and serum sampling were performed every 6 months with a minimum follow-up time of 12 months. MAIN OUTCOME MEASURES: Secondary outcomes included differences in BCVA (at 24 and 36 months), CS, Raman counts, serum antioxidant levels, and progression along the AMD severity scale (at 12, 24, and 36 months). RESULTS: The differential between active and placebo groups increased steadily, with average BCVA in the former being approximately 4.8 letters better than the latter for those who had 36 months of follow-up, and this difference was statistically significant (P = 0.04). In the longitudinal analysis, for a 1-log-unit increase in serum L, visual acuity was better by 1.4 letters (95% confidence interval, 0.3-2.5; P = 0.01), and a slower progression along a morphologic severity scale (P = 0.014) was observed. CONCLUSIONS: Functional and morphologic benefits were observed in key secondary outcomes after supplementation with L, Z, and coantioxidants in persons with early AMD.

Investigation of genetic variation in scavenger receptor class B, member 1 (SCARB1) and association with serum carotenoids.

OBJECTIVE: To investigate association of scavenger receptor class B, member 1 (SCARB1) genetic variants with serum carotenoid levels of lutein (L) and zeaxanthin (Z) and macular pigment optical density (MPOD). DESIGN: A cross-sectional study of healthy adults aged 20 to 70. PARTICIPANTS: We recruited 302 participants after local advertisement. METHODS: We measured MPOD by customized heterochromatic flicker photometry. Fasting blood samples were taken for serum L and Z measurement by high-performance liquid chromatography and lipoprotein analysis by spectrophotometric assay. Forty-seven single nucleotide polymorphisms (SNPs) across SCARB1 were genotyped using Sequenom technology. Association analyses were performed using PLINK to compare allele and haplotype means, with adjustment for potential confounding and correction for multiple comparisons by permutation testing. Replication analysis was performed in the TwinsUK and Carotenoids in Age-Related Eye Disease Study (CAREDS) cohorts. MAIN OUTCOME MEASURES: Odds ratios for MPOD area, serum L and Z concentrations associated with genetic variations in SCARB1 and interactions between SCARB1 and gender. RESULTS: After multiple regression analysis with adjustment for age, body mass index, gender, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, smoking, and dietary L and Z levels, 5 SNPs were significantly associated with serum L concentration and 1 SNP with MPOD (P<0.01). Only the association between rs11057841 and serum L withstood correction for multiple comparisons by permutation testing (P<0.01) and replicated in the TwinsUK cohort (P = 0.014). Independent replication was also observed in the CAREDS cohort with rs10846744 (P = 2×10(-4)), an SNP in high linkage disequilibrium with rs11057841 (r(2) = 0.93). No interactions by gender were found. Haplotype analysis revealed no stronger association than obtained with single SNP analyses. CONCLUSIONS: Our study has identified association between rs11057841 and serum L concentration (24% increase per T allele) in healthy subjects, independent of potential confounding factors. Our data supports further evaluation of the role for SCARB1 in the transport of macular pigment and the possible modulation of age-related macular degeneration risk through combating the effects of oxidative stress within the retina. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosures may be found after the references.

Concordance of macular pigment measurements obtained using customized heterochromatic flicker photometry, dual-wavelength autofluorescence, and single-wavelength reflectance.

This study compares in vivo measurements of macular pigment (MP) obtained using customized heterochromatic flicker photometry (cHFP; Macular Metrics Densitometer(™)), dual-wavelength fundus autofluorescence (Heidelberg Spectralis(®) HRA + OCT MultiColor) and single-wavelength fundus reflectance (Zeiss Visucam(®) 200). MP was measured in one eye of 62 subjects on each device. Data from 49 subjects (79%) was suitable for analysis. Agreement between the Densitometer and Spectralis was investigated at various eccentricities using a variety of quantitative and graphical methods, including: Pearson correlation coefficient to measure degree of scatter (precision), accuracy coefficient, concordance correlation coefficient (ccc), paired t-test, scatter and Bland-Altman plots. The relationship between max MP from the Visucam and central MP from the Spectralis and Densitometer was investigated using regression methods. Agreement was strong between the Densitometer and Spectralis at all central eccentricities (e.g. at 0.25° eccentricity: accuracy = 0.97, precision = 0.90, ccc = 0.87). Regression analysis showed a very weak relationship between the Visucam and Densitometer (e.g. Visucam max on Densitometer central MP: R(2) = 0.008, p = 0.843). Regression analysis also demonstrated a weak relationship between MP measured by the Spectralis and Visucam (e.g. Visucam max on Spectralis central MP: R(2) = 0.047, p = 0.348). MP values obtained using the Heidelberg Spectralis are comparable to MP values obtained using the Densitometer. In contrast, MP values obtained using the Zeiss Visucam are not comparable with either the Densitometer or the Spectralis MP measuring devices. Taking cHFP as the current standard to which other MP measuring devices should be compared, the Spectralis is suitable for use in a clinical and research setting, whereas the Visucam is not.

Candidate gene study of macular response to supplemental lutein and zeaxanthin.

Supplementation with carotenoids is proposed to protect against age-related macular degeneration. There is, however, considerable variability in retinal macular pigment response, which may be due to underlying genetic variation. The purpose of this study was to determine whether genetic factors, which have been previously associated with cross-sectional macular pigment levels in the retina or serum lutein, also influence response to supplementation. To this end we conducted an association study in 310 subjects from the TwinsUK cohort between variants in 8 candidate genes and serum lutein and retinal macular pigment optical density (MPOD) levels before and after supplementation. Four variants were associated with MPOD response to supplementation (p < 0.05): rs11057841 (SCARB1), rs4926339 (RPE65), rs1929841 (ABCA1) and rs174534 (FADS1). We also confirmed previous associations between rs6564851 near BMCO1 (p < 0.001) and rs11057841 within SCARB1 (p = 0.01) and baseline measures of serum lutein; while the latter was also associated with MPOD response, none of the BMCO1 variants were. Finally, there was evidence for association between variants near RPE65 and ELOVL2 and changes in lutein concentration after supplementation. This study is the first to show association between genetic variants and response to carotenoids supplementation. Our findings suggest an important link between MP response and the biological processes of carotenoids transport and fatty acid metabolism.

Serum response to supplemental macular carotenoids in subjects with and without age-related macular degeneration.

Macular pigment (MP) is composed of lutein (L), zeaxanthin (Z) and meso-zeaxanthin (MZ). The present study reports on serum response to three different MP supplements in normal subjects (n 27) and in subjects with age-related macular degeneration (AMD) (n 27). Subjects were randomly assigned to: Group 1 (20 mg L and 2 mg Z), Group 2 (10 mg L, 2 mg Z and 10 mg MZ) or Group 3 (3 mg L, 2 mg Z and 17 mg MZ). Serum carotenoids were quantified at baseline, and at 4 and 8 weeks using HPLC. Response data for normal and AMD subjects were comparable and therefore combined for analysis. We report response as the average of the 4- and 8-week concentrations (saturation plateau). Serum L increased significantly in Group 1 (0·036 µmol/l per mg (269 %); P< 0·001) and Group 2 (0·079 µmol/l per mg (340 %); P< 0·001), with no significant change in Group 3 (0·006 µmol/l per mg (7 %); P= 0·466). Serum Z increased significantly in Group 1 (0·037 µmol/l per mg (69 %); P= 0·001) and Group 2 (0·015 µmol/l per mg (75 %); P< 0·001), with no significant change in Group 3 ( − 0·0002 µmol/l per mg ( − 6 %); P= 0·384). Serum MZ increased significantly in Group 1 (0·0094 µmol/l (absolute value); P= 0·015), Group 2 (0·005 µmol/l per mg; P< 0·001) and Group 3 (0·004 µmol/l per mg; P< 0·001). The formulation containing all three macular carotenoids (Group 2 supplement) was the most efficacious in terms of achieving the highest combined concentration of the three MP constituent carotenoids in serum, thereby potentially optimising the bioavailability of these compounds for capture by the target tissue (retina).

Nutrient reference values for bioactives: new approaches needed? A conference report.

Nutrients can be classified as either "essential" or "non-essential," the latter are also termed bioactive substances. Whereas the absence of essential nutrients from the diet results in overt deficiency often times with moderate to severe physiological decrements, the absence of bioactive substances from the diet results in suboptimal health. Nutrient reference values are set by Codex Alimentarius and regulatory bodies in many countries, mostly for essential nutrients with recommended daily intakes. The IOM in the United States has defined a set of four DRIs that, when data are appropriate, include an EAR, a RDA that is derived from the EAR, an AI for nutrients without appropriate data to identify an EAR, and an UL. From the RDA, the United States derives a labeling value called the DV, which applies to older children and most adults. In Codex, the equivalents of the DVs are the NRVs to be used in calculating percentage values on food labels. Nothing in the IOM documents specifies that labeling values can be set only for what have been defined to date as essential nutrients. Indeed, the US Food and Drug Administration sets a labeling value for dietary fiber based on the IOM AI for this ingredient. This conference explores the definitions, concepts, and data on two of the best examples of bioactive substances that, perhaps, should have NRVs: lutein and zeaxanthin, and n-3 long-chain polyunsaturated fatty acids.

Nannoperca pygmaea, a new species of pygmy perch (Teleostei: Percichthyidae) from Western Australia.

A new species of pygmy perch (Percichthyidae) from south-western Australia is described on the basis of 15 specimens collected from the Hay River system. Nannoperca pygmaea sp. nov. differs from the sympatric congener N. vittata (Castelnau) by the absence of dark pigment on the ventral surface anterior to the anus, the possession of thin latero-ventral stripes, generally fewer dorsal rays and fewer anal rays, hind margin of scales on caudal peduncle without distinct pigment, and a more pronounced spot (ocellus) that is surrounded by a halo at the termination of the caudal peduncle. The new species is distinguished from congeners Nannoperca australis Günther, N. oxleyana Whitley and N. variegata Kuiter and Allen in possessing an exposed and serrated preorbital bone and jaws that may just reach to below the anterior margin of the eye, versus a smooth and hidden preorbital and the jaws reaching to at least below the pupil; and from the remaining congener, N. obscura (Klunzinger) in possessing a distinct haloed ocellus at base of caudal fin versus an indistinct barring, as well as a dark spot behind operculum, and the lack of dusky scale margins. It differs from the other sympatric pygmy perch found in the region, N. balstoni Regan, by the presence of an exposed rear edge of the preorbital (vs. hidden under skin), fewer transverse scale rows (13 vs. 15-16), small mouth (rarely reaching eye vs. reaching well beyond eye), ctenoid (vs. cycloid) body scales, generally fewer pectoral rays and smaller maximum size. Allozyme analyses unequivocally demonstrate that sympatric populations of N. pygmaea sp. nov. and N. vittata belong in different genetic lineages, display no genetic intermediates, and are diagnosable by fixed allozyme differences at 15 different loci. Due to its extremely restricted range, where it is known from only 0.06 km2, N. pygmaea sp. nov. requires urgent legislative protection.