Vannella mustalahtiana sp. nov. (Amoebozoa, Vannellida) and rainbow trout nodular gill disease (NGD) in Russia.

An outbreak of nodular gill disease (NGD) in farmed rainbow trout Oncorhynchus mykiss (Walbaum, 1792) was recorded in Ladoga Lake (Karelia, north-western Russia) in Spring 2020. The disease was characterised by typical clinical signs including asphyxiation, distended opercula, loss of activity and swimming upside down under the water surface. Maximum monthly mortality was 15.2%. The histological examination of the gills showed deformation and clubbing of lamellae, epithelial hypertrophy and hyperplasia, lamellar fusion and fusion of filaments. Granulomas were located within the epithelial layer and/or rose above its surface. Light microscopic in vivo observations of the mucus smears from the affected gills revealed numerous amoeboid protists demonstrating a flattened body when adhering to the substratum, and blunt, radiating pseudopodia when afloat. Based on these morphological characters, these amoebae could be assigned to the Discosea (Amoebozoa), and analyses of their small subunit rRNA gene sequences showed that they belonged to the genus Vannella Bovee, 1965. The results reported herein support the designation of a new species, V. mustalahtiana sp. nov. Despite having been isolated from the gills of a freshwater fish, the species belongs to a clade of Vannella comprising mostly species isolated from marine and brackish water habitats. These findings may be essential for the aetiology and treatment of the disease.

Blue Waters, Green Bottoms: Benthic Filamentous Algal Blooms Are an Emerging Threat to Clear Lakes Worldwide.

Nearshore (littoral) habitats of clear lakes with high water quality are increasingly experiencing unexplained proliferations of filamentous algae that grow on submerged surfaces. These filamentous algal blooms (FABs) are sometimes associated with nutrient pollution in groundwater, but complex changes in climate, nutrient transport, lake hydrodynamics, and food web structure may also facilitate this emerging threat to clear lakes. A coordinated effort among members of the public, managers, and scientists is needed to document the occurrence of FABs, to standardize methods for measuring their severity, to adapt existing data collection networks to include nearshore habitats, and to mitigate and reverse this profound structural change in lake ecosystems. Current models of lake eutrophication do not explain this littoral greening. However, a cohesive response to it is essential for protecting some of the world's most valued lakes and the flora, fauna, and ecosystem services they sustain.

A morphological and molecular reinvestigation of Janickina pigmentifera (Grassi, 1881) Chatton 1953 - an amoebozoan parasite of arrow-worms (Chaetognatha).

Amoebozoan parasites of arrow-worms (Chaetognatha) were isolated from their hosts living in plankton of the Bay of Villefranche (Mediterranean Sea). Based on the light microscopic characters, the amoebae were identified as Janickina pigmentifera (Grassi, 1881) by their limax locomotive form and due to the presence of the intracellular symbiont, Perkinsela amoebae, surrounded by a layer of pigment granules. Sequences of the 18S rRNA gene of both J. pigmentifera and its symbiont were obtained for the first time. The molecular phylogenetic analyses of 18S rRNA gene placed J. pigmentifera within the genus Neoparamoeba, a taxon also characterized by the presence of a symbiont, known as Perkinsela amoebae-like organism (PLO). The 18S rRNA gene sequence of P. amoebae from J. pigmentifera grouped with the sequences of 18S rRNA genes of PLOs from Neoparamoeba branchiphila and Neoparamoeba invadens. The first photo documentation of the light microscopic features of J. pigmentifera, such as locomotive form, the morphology of the nucleus and P. amoebae have been provided. The new results support the affinity of J. pigmentifera with the family Paramoebidae suggested previously based on the presence of PLO. In contrast to Janickina, typical members of Paramoebidae (Neoparamoeba and Paramoeba) have a flattened, dactylopodial locomotive form. This discrepancy in morphology can be explained by the obligate parasitic lifestyle of Janickina.

A Comparative Characterization of the Mitochondrial Genomes of Paramoeba aparasomata and Neoparamoeba pemaquidensis (Amoebozoa, Paramoebidae).

Marine amebae of the genus Paramoeba (Amoebozoa, Dactylopodida) normally contain a eukaryotic endosymbiont known as Perkinsela-like organism (PLO). This is one of the characters to distinguish the genera Neoparamoeba and Paramoeba from other Dactylopodida. It is known that the PLO may be lost, but PLO-free strains of paramoebians were never available for molecular studies. Recently, we have described the first species of the genus Paramoeba which has no parasome-Paramoeba aparasomata. In this study, we present a mitochondrial genome of this species, compare it with that of Neoparamoeba pemaquidensis, and analyze the evolutionary dynamics of gene sequences and gene order rearrangements between these species. The mitochondrial genome of P. aparasomata is 46,254 bp long and contains a set of 31 protein-coding genes, 19 tRNAs, two rRNA genes, and 7 open reading frames. Our results suggest that these two mitochondrial genomes within the genus Paramoeba have rather similar organization and gene order, base composition, codon usage, the composition and structure of noncoding, and overlapping regions.

Nephrocystidium pickii Weissenberg, 1921 belongs to Myxozoa (Cnidaria) but is not conspecific with Myxidium lieberkuehni Bütschli, 1882 (Myxozoa: Bivalvulida: Variisporina: Myxidiidae): molecular-genetic evidence.

We isolated and re-investigated Nephrocystidium pickii Weißenberg, 1921 (Myxozoa: Bivalvulida: Variisporina) using light microscopy and phylogenetic analysis of the small-subunit (SSU) ribosomal RNA gene. This species is a parasite of the northern pike Esox lucius L. (Actinopterygii: Esocidae) which localizes in the endothelial cells of the glomerular capillary. The results of the phylogenetic analysis including this species clarify its taxonomic status and show that although it is the closest relative to Myxidium lieberkuehni Bütschli, 1882, the two organisms are not conspecific, contrary to the earlier hypotheses. The data obtained highlight the necessity of a profound taxonomic revision of the Myxozoa and the need to clarify species affiliation of extrasporogonic developmental stages of these organisms that occur in different organs of fish.

Effects of interpretive front-of-pack nutrition labels on food purchases: protocol for the Starlight randomised controlled trial.

BACKGROUND: Interpretive front-of-pack nutrition labels are better understood than non-interpretive labels. However, robust evidence on the effects of such labels on consumer food purchases in the real-world is lacking. Our aim is to assess the effects of two interpretive front-of-pack nutrition labels, compared with a non-interpretive label, on the healthiness of consumer food purchases. METHODS/DESIGN: A five-week (1-week baseline and 4-week intervention) three-arm parallel randomised controlled trial will be conducted using a bespoke smartphone application, which will administer study questionnaires and deliver intervention (Multiple Traffic Light and Health Star Rating) and control (Nutrition Information Panel) labels. To view their allocated nutrition label, participants scan the barcode of packaged food products using their smartphone camera. The assigned label is displayed instantly on the smartphone screen.1500 eligible participants (New Zealand adult smartphone owners who shop in a supermarket at least once a week and are main household shoppers) will be randomised in a 1:1:1 ratio to one of the three nutrition label formats, using computer-generated randomisation sequences. Randomisation will be stratified by ethnicity and interest in healthy eating. Food and beverage purchase data will be collected continuously throughout the study via hard copy till receipts and electronic grocery purchase lists recorded and transmitted using the smartphone application. The primary outcome will be healthiness of food purchases in each trial arm, assessed as mean Food Standards Australia New Zealand nutrient profiling score criterion score for all food and beverages purchased over the intervention period. Secondary outcomes will include saturated fat, sugar, sodium and energy content of food purchases; food expenditure; labelling profile of food purchases (i.e. mean number of Health Star Rating stars and proportion of red, green and amber traffic lights); nutrient profiling score over time and by food categories; purchases of unpackaged foods; self-reported nutrition knowledge and recorded use of assigned labelling system. DISCUSSION: The Starlight randomised, controlled trial will determine the effects of interpretive front-of-pack nutrition labels on the healthiness of consumer food purchases in the real world. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12614000644662 (registered 18 June 2014).

Optimism, Resilience, and General Self-Efficacy Predict Lower Somatic Burden during the COVID-19 Pandemic.

There is scarce evidence of a relationship between positive and psychosomatic characteristics. This study aimed to examine the associations of somatic burden with psychological resources such as optimism, resilience, and general self-efficacy. Russian participants (n = 1020) completed measures of psychological resources at Time 1 and somatic symptoms at Time 2. The results showed that somatic burden decreased with greater levels of optimism, resilience, and general self-efficacy. Regarding health and sociodemographic characteristics, female sex increased somatic burden in the model with optimism scores, university education decreased somatic burden in the model with resilience scores, and history of COVID-19 disease increased somatic burden in the models with optimism, resilience, and general self-efficacy scores. This study has theoretical and practical contributions. It combines positive psychology and psychosomatic medicine and highlights the value of psychological resource interventions in the treatment and prevention of somatic burden. These findings may be useful for scientists, clinicians, and practitioners.

Somatic burden in Russia during the COVID-19 pandemic.

Somatic burden has become one of the most common psychological reactions to the COVID-19 pandemic worldwide. This study examined the prevalence of somatic burden, latent profiles, and associated factors of somatic symptoms during the pandemic in a large sample of Russians. We used cross-sectional data from 10,205 Russians collected during October-December, 2021. Prevalence of somatic burden was assessed with the Somatic Symptom Scale-8. Latent profiles of somatic burden were identified using latent profile analysis. Multinomial logistic regression was used to examine demographic, socioeconomic, and psychological associated factors of somatic burden. Over one-third (37%) of the Russians reported being somatised. We selected the three-latent profile solution with high somatic burden profile (16%), medium somatic burden profile (37%), and low somatic burden profile (47%). The associated factors of greater somatic burden were female gender, lower education, history of COVID-19 disease, refusing vaccination against SARS-CoV-2 infection, poorer self-rated health, greater fear of COVID-19 pandemic, and living in regions with higher excess mortality. Overall, this study contributes to knowledge about the prevalence, latent profiles, and associated factors of somatic burden during the COVID-19 pandemic. It can be useful to researchers in psychosomatic medicine and practitioners in the health care system.

Coronamoeba villafranca gen. nov. sp. nov. (Amoebozoa, Dermamoebida) challenges the correlation of morphology and phylogeny in Amoebozoa.

Coronamoeba villafranca gen. nov. sp. nov. is a small amoeba isolated from the surface planktonic biotope in the Bay of Villefranche (Mediterranean Sea). It has a confusing set of morphological and molecular characters. Its locomotive form is subcylindrical and monopodial with monoaxial cytoplasmic flow and occasional hyaline bulging at the anterior edge (a monotactic morphotype). Based on this set of characters, this amoeba is most similar to members of the genus Nolandella (Tubulinea, Euamoebida). However, molecular phylogenetic analysis based on only the small subunit ribosomal RNA (SSU rRNA) gene and on two concatenated markers (SSU rRNA gene and actin) robustly places this species in the Discosea, specifically, in a clade with Dermamoeba and Paradermamoeba (Dermamoebida) as the closest described relatives, and several SSU rRNA clones from environmental DNA. A unique glycocalyx of the studied amoeba consisting of complex separate units with pentameric symmetry may be considered a unifying character of this species with other dermamoebids. The monotactic morphotype demonstrated by these amoebae primarily occurs in Tubulinea but was recently confirmed in other clades of Amoebozoa (e.g. Dactylopodida and Variosea). This morphotype may be the plesiomorphic mode of cell organization in Amoebozoa that might have evolved in the last amoebozoan common ancestor (LACA) and conserved in several lineages of this group. It may reflect basic characteristics of the cytoskeletal structure and functions in Amoebozoa.

Self-organization of cellular structures induced by the overexpression of nuclear envelope proteins: a correlative light and electron microscopy study.

The mechanisms by which the supramolecular order is formed inside the cell nucleus remain poorly understood. So far, two major hypotheses - ordered assembly and stochastic self-organization - have been discussed. To determine which mechanism is responsible for the formation of nuclear envelope, cells overexpressing one of the nuclear envelope proteins (lamin A, lamin B1, pom121 or ndc1) were investigated. According to the ordered assembly model, the presence of an excessive amount of a component has no effect in the formation of the normal structure of a nuclear envelope because it is programmed and cannot be distorted. In contrast, according to the self-organization concept, there is no such strictly determined cellular structures, and an excessive amount of even one component will affect the cellular organization. In the present study, formation of a redundant nuclear envelope was observed in the case of lamin B1 and lamin A overexpression. In the case of the nucleoporins pom121 and ndc1, no incorporation of the overexpressed proteins into the nuclear envelope was observed on the first day after transfection; however, the remodeling of endoplasmic reticulum elements and the formation of membrane aggregates in the cytoplasm were observed. After mitosis, pom121 from the cytoplasmic aggregates was translocated into the redundant nuclear envelope in which it induced inner nuclear membrane protrusions. Therefore, our results indicate that the formation of the nuclear envelope is not predetermined and that an excessive amount of even one protein component can affect cellular structure formation. This study concluded that nuclear envelope formation is achieved by the self-organization mechanism.

The effect of landmark and body-based sensory information on route knowledge.

Two experiments investigated the effects of landmarks and body-based information on route knowledge. Participants made four out-and-back journeys along a route, guided only on the first outward trip and with feedback every time an error was made. Experiment 1 used 3-D virtual environments (VEs) with a desktop monitor display, and participants were provided with no supplementary landmarks, only global landmarks, only local landmarks, or both global and local landmarks. Local landmarks significantly reduced the number of errors that participants made, but global landmarks did not. Experiment 2 used a head-mounted display; here, participants who physically walked through the VE (translational and rotational body-based information) made 36% fewer errors than did participants who traveled by physically turning but changing position using a joystick. Overall, the experiments showed that participants were less sure of where to turn than which way, and journey direction interacted with sensory information to affect the number and types of errors participants made.

A profile of prognostic and molecular factors in European and Maori breast cancer patients.

BACKGROUND: New Zealand Maori have a poorer outcome from breast cancer than non-Maori, yet prognostic data are sparse. The objective of this study was to quantify levels of prognostic factors in a cohort of self-declared Maori and European breast cancer patients from Christchurch, New Zealand. METHODS AND RESULTS: Clinicopathological and survival data from 337 consecutive breast cancer patients (27 Maori, 310 European) were evaluated. Fewer tumours were high grade in Maori women than European women (p = 0.027). No significant ethnic differences were detected for node status, tumour type, tumour size, human epidermal growth factor receptor, oestrogen and progesterone receptor (ER/PR) status, or survival.In addition, tumour and serum samples from a sub-cohort of 14 Maori matched to 14 NZ European patients were analyzed by immunohistochemistry and enzyme linked immunosorbent assay for molecular prognostic factors. Significant correlations were detected between increased grade and increased levels of hypoxia inducible factor-1 (HIF-1α), glucose transporter-1 (GLUT-1), microvessel density (MVD) and cytokeratins CK5/6 (p < 0.05). High nodal status correlated with reduced carbonic anhydrase IX (CA-IX). Negative ER/PR status correlated with increased GLUT-1, CA-IX and MVD. Within the molecular factors, increased HIF-1α correlated with raised GLUT-1, MVD and CK5/6, and CK5/6 with GLUT-1 and MVD (p < 0.05). The small number of patients in this sub-cohort limited discrimination of ethnic differences. CONCLUSIONS: In this Christchurch cohort of breast cancer patients, Maori women were no more likely than European women to have pathological or molecular factors predictive of poor prognosis. These data contrast with data from the North Island NZ, and suggest potential regional differences.

Cunea russae n. sp. (Amoebozoa, Dactylopodida), another cryptic species of Cunea Kudryavtsev and Pawlowski, 2015, inhabits a continental brackish-water biotope.

The genus Cunea Kudryavtsev and Pawlowski, 2015 (Amoebozoa, Dactylopodida) was initially described from the oceanic benthos: C. profundata, from over 5 km depth in the Atlantic Ocean, and C. thuwala from the Red Sea benthos at ca. 60 m depth. Both species are identical to each other in morphology (including cell coat ultrastructure), but differ significantly in the gene sequence data, including barcoding loci of small subunit ribosomal RNA and cytochrome oxidase subunit 1 gene, as well as actin. This paper describes the third species of Cunea, C. russae n. sp. isolated from a brackish water habitat without a direct connection to the ocean, a small spring of brackish water (19‰) emerging from a 246 m deep hole in the earth. This species is morphologically identical to the previous two amoebae, but differs from them significantly in the gene sequence data and ecological preferences. In particular, this species has the broadest salinity tolerance range, being able to reproduce well already at 2.5‰. It is also capable of resisting cold temperatures, like C. profundata. The data obtained suggest that the genus Cunea may comprise a significant taxonomic diversity represented by morphologically identical, but quickly diverging species with significant ecological plasticity.

Description of a new species of marine amoeba Korotnevella mutabilis n. sp. (Amoebozoa, Dactylopodida).

Korotnevella (Amoebozoa, Dactylopodida) is a genus of naked lobose amoebae with a dactylopodial morphotype. The cell membrane of these amoebae is covered with a monolayer of scales. The structure and size of scales are considered as species-specific features. Here, we describe a new marine species, Korotnevella mutabilis n. sp., isolated from the bottom sediment sample of Nivå Bay (Baltic Sea, The Sound) and studied with light and electron microscopy as well as with molecular phylogenetic analysis. This species has a number of morphological similarities with Korotnevella monacantholepis, such as size of the cell, L/B ratio, the nucleus structure and the type of a biotope from which both species were isolated. At the same time, Korotnevella mutabilis n. sp. differs from K. monacantholepis in the structure of basket-shaped scales: Korotnevella mutabilis n. sp. has an enclosed hammock-shaped latticework basket and up to two spines while K. monacantholepis has an opened two-row latticework basket and never has two spines. According to molecular phylogenetic analyses based on the sequences of the mitochondrial COI gene, Korotnevella mutabilis n. sp. is a distinct species, highly divergent from other Korotnevella species.

Vannella samoroda n. sp. (Amoebozoa) - First member of the genus from a continental saline habitat placed in a molecular tree.

Vannella samoroda n. sp. (Amoebozoa, Vannellida) was isolated from the mouth of the Malaya Samoroda river flowing into Elton, the largest European hypersaline lake (Russia). Among all rivers of the area, it has the highest salt content (ca. 110‰). Amoebae maintained in seawater medium with ca. 77‰ salts concentration had a set of morphological characters typical of Vannella spp.: rounded, fan-shaped, or spatulate locomotive form, floating form with bent, blunt-ended hyaline pseudopodia, and a cell coat consisting of regularly packed palisade elements and scarce simple filaments. Phylogenetic analyses based on SSU rRNA and cytochrome C oxidase subunit 1 genes show that the amoeba is most closely related to Vannella ebro Smirnov, 2001, but represents a distinct species. The clade of V. ebro and V. samoroda branches among marine species of Vannella. The studied species is the first member of the genus Vannella from a continental saline habitat described using molecular data. Interestingly, it has a broad range of salinity tolerance: cells reproduce above 18‰, while survival of a few cells regularly occurs even in highly diluted Prescott and James medium. The normal culture restores itself when PJ medium is substituted with 77‰ seawater medium even after months of experimental incubation.

Paramoeba aparasomata n. sp., a symbiont-free species, and its relative Paramoeba karteshi n. sp. (Amoebozoa, Dactylopodida).

Two brackish water amoebae have been isolated and studied from the benthic biotopes of the Chupa Inlet (Kandalaksha Bay, northwestern Russia). Both strains can be identified as new species of the genus Paramoeba (Amoebozoa, Dactylopodida, Paramoebidae) based on light microscopical characters, structure of microscales on the cell surface and molecular evidence based on the analyses of two genes, nuclear SSU rRNA and mitochondrial cytochrome c oxidase subunit 1 (COI). Paramoeba aparasomata n. sp. is of particular interest because this amoeba is permanently lacking a symbiotic Perkinsela-like organism (PLO) present in other species of Paramoeba and Neoparamoeba. The results obtained show that scaly dactylopodial amoebae lacking PLO are not necessarily members of Korotnevella. In particular, we suggest that Korotnevella nivo Smirnov, 1997, with microscales very similar to those of Paramoeba eilhardi and the species studied here in structure, may be in fact a member of Paramoeba. Molecular data on K. nivo have to be obtained and analysed to test this hypothesis. Based on our new results we emend the diagnosis of the genus Paramoeba to make it more fit to the current phylogenetic conception.

Clydonella sawyeri n. sp. (Amoebozoa, Vannellida): Morphological and molecular study and a re-definition of the genus Clydonella Sawyer, 1975.

We isolated and described a brackish-water amoeba, Clydonella sawyeri n. sp. (Amoebozoa, Vannellida), from the littoral habitat in Kandalaksha Bay (The White Sea, northwestern Russia). Morphology of this amoeba corresponds to the initially proposed diagnosis of the genus Clydonella Sawyer, 1975, although it is sufficiently different from other described species of this genus to warrant a distinct species designation. Phylogenetic analysis based on the small-subunit rRNA gene shows that this species is closely related to the two previously studied ATCC strains identified as Clydonella sp., for which only ultrastructural and molecular data were published. Cytochrome oxidase subunit 1 (COI) gene sequence of the studied species was for the first time obtained for Clydonella. Analysis of this marker shows that this genus belongs to Vannellida and is separated from the other vannellids sampled to date. Phylogenetic analysis of the concatenated SSU rRNA and COI genes dataset yields the best resolved position of Clydonella compared to both markers when analysed separately. Based on the data presented we finally link light microscopic, ultrastructural and molecular data in a description of a single strain, which allows a refinement of the diagnosis of the genus Clydonella.

Description of Neoparamoeba longipodia n. sp. and a new strain of Neoparamoeba aestuarina (Page, 1970) (Amoebozoa, Dactylopodida) from deep-sea habitats.

Two strains of lobose amoebae have been isolated from the deep-sea bottom sediments of the Sea of Japan (3.6km deep) and Western Atlantic Ocean (5.1km deep). Amoebae of both strains have a dactylopodial mophotype, intracellular kinetoplastid symbiont (Perkinsela-like organism) and have no microscales on the cell surface. The morphology and molecular data of the Sea of Japan strain allow us to unambiguously identify it as Neoparamoeba aestuarina (Page, 1970). At the same time, the Atlantic strain is described as a new species Neoparamoeba longipodia as it differs from other species of the genus Neoparamoeba in morphology and gene sequence data. The data presented expand the range of known habitats for the genus Neoparamoeba and permit further analysis of the phylogenetic relationships within this clade with the expanded set of molecular data.

Effectiveness of recruitment to a smartphone-delivered nutrition intervention in New Zealand: analysis of a randomised controlled trial.

OBJECTIVES: Delivery of interventions via smartphone is a relatively new initiative in public health, and limited evidence exists regarding optimal strategies for recruitment. We describe the effectiveness of approaches used to recruit participants to a smartphone-enabled nutrition intervention trial. METHODS: Internet and social media advertising, mainstream media advertising and research team networks were used to recruit New Zealand adults to a fully automated smartphone-delivered nutrition labelling trial (no face-to-face visits were required). Recruitment of Maori and Pacific participants was a key focus and ethically relevant recruitment materials and approaches were used where possible. The effectiveness of recruitment strategies was evaluated using Google Analytics, monitoring of study website registrations and randomisations, and self-reported participant data. The cost of the various strategies and associations with participant demographics were assessed. RESULTS: Over a period of 13 months, there were 2448 registrations on the study website, and 1357 eligible individuals were randomised into the study (55%). Facebook campaigns were the most successful recruitment strategy overall (43% of all randomised participants) and for all ethnic groups (Maori 44%, Pacific 44% and other 43%). Significant associations were observed between recruitment strategy and age (p<0.001), household size (p<0.001), ethnicity (p<0.001), gender (p=0.005) and interest in healthy eating (p=0.022). Facebook campaigns resulted in the highest absolute numbers of study registrations and randomisations (966 and 584, respectively). Network strategies and Facebook campaigns cost least per randomised participant (NZ$4 and NZ$5, respectively), whereas radio advertising costs most (NZ$179 per participant). CONCLUSION: Internet and social media advertising were the most effective and least costly approaches to recruiting participants to a smartphone-delivered trial. These approaches also reached diverse ethnic groups. However, more culturally appropriate recruitment strategies are likely to be necessary in studies where large numbers of participants from specific ethnic groups are sought. TRIAL REGISTRATION: ACTRN12614000644662; Post-results.

Effects of interpretive nutrition labels on consumer food purchases: the Starlight randomized controlled trial.

Background: Nutrition labeling is a prominent policy to promote healthy eating.Objective: We aimed to evaluate the effects of 2 interpretive nutrition labels compared with a noninterpretive label on consumer food purchases.Design: In this parallel-group randomized controlled trial, we enrolled household shoppers across New Zealand who owned smartphones and were aged ≥18 y. Eligible participants were randomly assigned (1:1:1) to receive either traffic light labels (TLLs), Health Star Rating labels (HSRs), or a control [nutrition information panel (NIP)]. Smartphone technology allowed participants to scan barcodes of packaged foods and to receive allocated labels on their smartphone screens. The primary outcome was the mean healthiness of all packaged food purchases over the 4-wk intervention period, which was measured by using the Food Standards Australia New Zealand Nutrient Profiling Scoring Criterion (NPSC).Results: Between October 2014 and November 2015, 1357 eligible shoppers were randomly assigned to TLL (n = 459), HSR (n = 443), or NIP (n = 455) labels. Overall difference in the mean transformed NPSC score for the TLL group compared with the NIP group was -0.20 (95% CI: -0.94, 0.54; P = 0.60). The corresponding difference for HSR compared with NIP was -0.60 (95% CI: -1.35, 0.15; P = 0.12). In an exploratory per-protocol analysis of participants who used the labeling intervention more often than average (n = 423, 31%), those who were assigned to TLL and HSR had significantly better NPSC scores [TLL compared with NIP: -1.33 (95% CI: -2.63, -0.04; P = 0.04); HSR compared with NIP: -1.70 (95% CI: -2.97, -0.43; P = 0.01)]. Shoppers who were randomly assigned to HSR and TLL also found the labels significantly more useful and easy to understand than the NIP (all P values <0.001).Conclusions: At the relatively low level of use observed in this trial, interpretive nutrition labels had no significant effect on food purchases. However, shoppers who used interpretive labels found them to be significantly more useful and easy to understand, and compared with frequent NIP users, frequent TLL and HSR users had significantly healthier food purchases. This trial was registered at the Australian New Zealand Clinical Trials Registry (https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=366446&isReview=true) as ACTRN12614000644662.