Distinctive Renal Lesion of Spirochete-Infected Brine Shrimp

In spirochete-infected Artemia, the renal tubule exhibited a lesion consisting of a group of spirochetes situated in an indentation of the base of the epithelium and involving discontinuity of the basal lamina.     

Proteomics Investigation of Diverse Serological Patterns in COVID-19

Serum antibodies IgM and IgG are elevated during Coronavirus Disease 2019 (COVID-19) to defend against viral attacks. Atypical results such as negative and abnormally high antibody expression were frequently observed whereas the underlying molecular mechanisms are elusive. In our cohort of 144 COVID-19 patients, 3.5% were both IgM and IgG negative, whereas 29.2% remained only IgM negative. The remaining patients exhibited positive IgM and IgG expression, with 9.3% of them exhibiting over 20-fold higher titers of IgM than the others at their plateau. IgG titers in all of them were significantly boosted after vaccination in the second year. To investigate the underlying molecular mechanisms, we classed the patients into four groups with diverse serological patterns and analyzed their 2-year clinical indicators. Additionally, we collected 111 serum samples for TMTpro-based longitudinal proteomic profiling and characterized 1494 proteins in total. We found that the continuously negative IgM and IgG expression during COVID-19 were associated with mild inflammatory reactions and high T cell responses. Low levels of serum IgD, inferior complement 1 activation of complement cascades, and insufficient cellular immune responses might collectively lead to compensatory serological responses, causing overexpression of IgM. Serum CD163 was positively correlated with antibody titers during seroconversion. This study suggests that patients with negative serology still developed cellular immunity for viral defense and that high titers of IgM might not be favorable to COVID-19 recovery.     

Culture-Free Survey Reveals Diverse and Distinctive Fungal Communities Associated with Developing Figs (Ficus spp.) in Panama

The ancient association of figs (Ficus spp.) and their pollinating wasps (fig wasps; Chalcidoidea, Hymenoptera) is one of the most interdependent plant–insect mutualisms known. In addition to pollinating wasps, a diverse community of organisms develops within the microcosm of the fig inflorescence and fruit. To better understand the multipartite context of the fig–fig wasp association, we used a culture-free approach to examine fungal communities associated with syconia of six species of Ficus and their pollinating wasps in lowland Panama. Diverse fungi were recovered from surface-sterilized flowers of all Ficus species, including gall- and seed flowers at four developmental stages. Fungal communities in syconia and on pollinating wasps were similar, dominated by diverse and previously unknown Saccharomycotina, and distinct from leaf- and stem endophyte communities in the same region. Before pollination, fungal communities were similar between gall- and seed flowers and among Ficus species. However, fungal communities differed significantly in flowers after pollination vs. before pollination, and between anciently diverged lineages of Ficus with active vs. passive pollination syndromes. Within groups of relatively closely related figs, there was little evidence for strict-sense host specificity between figs and particular fungal species. Instead, mixing of fungal communities among related figs, coupled with evidence for possible transfer by pollinating wasps, is consistent with recent suggestions of pollinator mixing within syconia. In turn, changes in fungal communities during fig development and ripening suggest an unexplored role of yeasts in the context of the fig–pollinator wasp mutualism.     

A Distinctive Nerve Cell Type Common to Diverse Deuterostome Larvae: Comparative Data from Echinoderms,Hemichordates and Amphioxus

Abstract The larval ciliary bands of echinoderm bipinnaria and pluteus larvae and the hemichordate tornaria contain similar multipolar or bipolar nerve cells with unusual apical processes that run across the surface of the band between the bases of its cilia. We report on some distinctive ultrastructural features of these cells. Among these are specialized junctions that occur between the cells' apical processes and adjacent ciliary band cells near the base of each cilium. Such structures are best developed in pluteus larvae. Many nerve cells in the larval spinal cord of amphioxus also have large apical processes that cross the central lumen of the cord. We interpret our observations on these cells in terms of Garstang's hypothesis, which derives the chordate neural tube from a larval ciliary band, and suggest that multipolar cells like those in echinoderm and tornaria bands may be the antecedents of some categories of neurons in the chordate spinal cord.     

Prey Patch Patterns Predict Habitat Use by Top Marine Predators with Diverse Foraging Strategies

Spatial coherence between predators and prey has rarely been observed in pelagic marine ecosystems. We used measures of the environment, prey abundance, prey quality, and prey distribution to explain the observed distributions of three co-occurring predator species breeding on islands in the southeastern Bering Sea: black-legged kittiwakes (Rissa tridactyla), thick-billed murres (Uria lomvia), and northern fur seals (Callorhinus ursinus). Predictions of statistical models were tested using movement patterns obtained from satellite-tracked individual animals. With the most commonly used measures to quantify prey distributions - areal biomass, density, and numerical abundance - we were unable to find a spatial relationship between predators and their prey. We instead found that habitat use by all three predators was predicted most strongly by prey patch characteristics such as depth and local density within spatial aggregations. Additional prey patch characteristics and physical habitat also contributed significantly to characterizing predator patterns. Our results indicate that the small-scale prey patch characteristics are critical to how predators perceive the quality of their food supply and the mechanisms they use to exploit it, regardless of time of day, sampling year, or source colony. The three focal predator species had different constraints and employed different foraging strategies – a shallow diver that makes trips of moderate distance (kittiwakes), a deep diver that makes trip of short distances (murres), and a deep diver that makes extensive trips (fur seals). However, all three were similarly linked by patchiness of prey rather than by the distribution of overall biomass. This supports the hypothesis that patchiness may be critical for understanding predator-prey relationships in pelagic marine systems more generally.     

Divergence Times and Phylogenetic Patterns of Sebacinales,a Highly Diverse and Widespread Fungal Lineage

Patterns of geographic distribution and composition of fungal communities are still poorly understood. Widespread occurrence in terrestrial ecosystems and the unique richness of interactions of Sebacinales with plants make them a target group to study evolutionary events in the light of nutritional lifestyle. We inferred diversity patterns, phylogenetic structures and divergence times of Sebacinales with respect to their nutritional lifestyles by integrating data from fossil-calibrated phylogenetic analyses. Relaxed molecular clock analyses indicated that Sebacinales originated late Permian within Basidiomycota, and their split into Sebacinaceae and Serendipitaceae nom. prov. likely occurred during the late Jurassic and the early Cretaceous, coinciding with major diversifications of land plants. In Sebacinaceae, diversification of species with ectomycorrhizal lifestyle presumably started during the Paleocene. Lineage radiations of the core group of ericoid and cavendishioid mycorrhizal Sebacinales started probably in the Eocene, coinciding with diversification events of their hosts. The diversification of Sebacinales with jungermannioid interactions started during the Oligocene, and occurred much later than the diversification of their hosts. Sebacinales communities associated either with ectomycorrhizal plants, achlorophyllous orchids, ericoid and cavendishioid Ericaceae or liverworts were phylogenetically clustered and globally distributed. Major Sebacinales lineage diversifications started after the continents had drifted apart. We also briefly discuss dispersal patterns of extant Sebacinales.     

Practice Patterns in Screening for Metabolic Disease in Women with PCOS of Diverse Race-Ethnic Backgrounds

ObjectivesWomen with polycystic ovary syndrome (PCOS) are at high risk for metabolic disorders, which prompted the American Association of Clinical Endocrinologists (AACE) to publish a 2005 position statement recommending screening for metabolic disease.The purposes of the present study were to 1) to examine changes in screening rates for obesity, type 2 diabetes (T2D), metabolic syndrome (MetS), hyperlipidemia (HL), nonalcoholic fatty liver disease (NAFLD), and hypertension (HTN) in women with PCOS after publication of the 2005 AACE position statement and 2) to determine if screening rates and metabolic disorders vary by race-ethnicity.MethodsPCOS cases in 2006 (n = 547) and 2011 (n = 1,159) and metabolic disorders were identified by International Classification of Diseases, 9th revision (ICD9) code. Screening rates for metabolic disorders were determined by the presence of blood tests (hemoglobin A1c [HbA_1c], lipid profile, alanine aminotransferase/aspartate aminotransferase [ALT/AST]).ResultsIn 2006, ≤ 25% of PCOS patients underwent recommended screening tests: HbA1c 18%; lipid profile < 20%; ALT/AST ≤ 25%. By 2011, only HbA1c testing had increased (18% to 21%). Obesity increased from 35% to 40%, while other metabolic disorders remained stable. Black women had the highest rates of obesity and HTN in 2011 (Obesity: Black 48%, Hispanic 44%, White 33%, Other 31%, P < .0001; HTN: Black 18%, Hispanic 9%, White 10%, Other 7%, P < .0001). Blacks and Hispanics were screened more often with ALT/AST testing (Black 27/27%, Hispanic 28/27%, White 23/22%, Other 17/18%, P = .02/.03). Screening rates were higher in the endocrine clinic for all metabolic disorders than in other clinics (P < .05).ConclusionDespite the publication of recommendations in 2005, screening rates for metabolic disease in women with PCOS remained low across all race-ethnicities in 2011. (Endocr Pract. 2014;20:855-863)     

The Allure of the Distinctive: Reduced Sexual Responsiveness of Female Guppies to 'Redundant' Male Colour Patterns

Frequency-dependent mating behaviour has the potential to maintain genetic variation in characteristics of organisms. The colour patterns of guppies ( Poecilia reticulata ) provide an example of one of the most extreme genetically based polymorphisms known in nature, for which frequency-dependent mate choice could be a mechanism. Numerous studies have shown that female guppies base mating preferences on male colour patterns and there is evidence that females prefer to mate with males displaying novel or unfamiliar colour patterns. This preference could lead to frequency-dependent mating success in males. Nevertheless, the possibility that female sexual responsiveness itself may depend on the frequency of male types has not been tested systematically in guppies or any other species. This study examined the sexual responses of female guppies in experimental groups consisting of two males with similar (redundant) and two males with different (unique) colour patterns. We found that female guppies were much more likely to respond sexually to the displays of unique males than to those of redundant males. Further, there was no effect of orange colouration on female responsiveness as has been documented for this population in several previous studies, thus, discrimination against redundant male types appears to have overridden directional selection based on colour pattern characteristics. This discrimination against redundant male types could in turn lead to frequency-dependent mating success in males and maintenance of colour pattern polymorphism.     

Transposable Element Regulation in Rice and Arabidopsis: Diverse Patterns of Active Expression and siRNA-mediated Silencing

Transposable elements (TEs) are DNA segments that can mediate or cause movement within genomes. We performed a comprehensive, whole-genome analysis of annotated TEs in rice (Oryza sativa L.) and Arabidopsis thaliana, focusing on their expression (mRNA data) and silencing (small RNA data), and we compared these data with annotated genes that are not annotated as transposons. TEs demonstrated higher levels of antisense mRNA expression in comparison to non-TE genes. The majority of the TEs were silenced, as demonstrated by higher levels of small RNAs and a lack of mRNA MPSS data. When TEs were expressed, their activity was usually limited to just one or a few of the mRNA libraries. When we examined TE expression at the whole-genome level and across the complete mRNA dataset, we observed that most activity was contributed by a few highly expressed transposable elements. These TEs were characterized by their low copy number and few matching small RNAs. Our results help define the relationship between gene expression and gene silencing for TEs, and indicate that TE silencing can impact neighboring genes, perhaps via a mechanism of heterochromatin formation and spreading. These data may be used to define active TEs and families of transposable elements that continue to shape plant genomes.     

Biogeographic Distribution Patterns and Their Correlates in the Diverse Frog Fauna of the Atlantic Forest Hotspot

Anurans are a highly diverse group in the Atlantic Forest hotspot (AF), yet distribution patterns and species richness gradients are not randomly distributed throughout the biome. Thus, we explore how anuran species are distributed in this complex and biodiverse hotspot, and hypothesize that this group can be distinguished by different cohesive regions. We used range maps of 497 species to obtain a presence/absence data grid, resolved to 50×50 km grain size, which was submitted to k-means clustering with v-fold cross-validation to determine the biogeographic regions. We also explored the extent to which current environmental variables, topography, and floristic structure of the AF are expected to identify the cluster patterns recognized by the k-means clustering. The biogeographic patterns found for amphibians are broadly congruent with ecoregions identified in the AF, but their edges, and sometimes the whole extent of some clusters, present much less resolved pattern compared to previous classification. We also identified that climate, topography, and vegetation structure of the AF explained a high percentage of variance of the cluster patterns identified, but the magnitude of the regression coefficients shifted regarding their importance in explaining the variance for each cluster. Specifically, we propose that the anuran fauna of the AF can be split into four biogeographic regions: a) less diverse and widely-ranged species that predominantly occur in the inland semideciduous forests; b) northern small-ranged species that presumably evolved within the Pleistocene forest refugia; c) highly diverse and small-ranged species from the southeastern Brazilian mountain chain and its adjacent semideciduous forest; and d) southern species from the Araucaria forest. Finally, the high congruence among the cluster patterns and previous eco-regions identified for the AF suggests that preserving the underlying habitat structure helps to preserve the historical and ecological signals that underlie the geographic distribution of AF anurans.     

L-Amino Acids Elicit Diverse Response Patterns in Taste Sensory Cells: A Role for Multiple Receptors

Umami, the fifth basic taste, is elicited by the L-amino acid, glutamate. A unique characteristic of umami taste is the response potentiation by 5’ ribonucleotide monophosphates, which are also capable of eliciting an umami taste. Initial reports using human embryonic kidney (HEK) cells suggested that there is one broadly tuned receptor heterodimer, T1r1+T1r3, which detects L-glutamate and all other L-amino acids. However, there is growing evidence that multiple receptors detect glutamate in the oral cavity. While much is understood about glutamate transduction, the mechanisms for detecting the tastes of other L-amino acids are less well understood. We used calcium imaging of isolated taste sensory cells and taste cell clusters from the circumvallate and foliate papillae of C57BL/6J and T1r3 knockout mice to determine if other receptors might also be involved in detection of L-amino acids. Ratiometric imaging with Fura-2 was used to study calcium responses to monopotassium L-glutamate, L-serine, L-arginine, and L-glutamine, with and without inosine 5’ monophosphate (IMP). The results of these experiments showed that the response patterns elicited by L-amino acids varied significantly across taste sensory cells. L-amino acids other than glutamate also elicited synergistic responses in a subset of taste sensory cells. Along with its role in synergism, IMP alone elicited a response in a large number of taste sensory cells. Our data indicate that synergistic and non-synergistic responses to L-amino acids and IMP are mediated by multiple receptors or possibly a receptor complex.     

Tree-Related Microhabitats Follow Similar Patterns but are More Diverse in Primary Compared to Managed Temperate Mountain Forests

Ecosystems - The impact of forest management on biodiversity is difficult to scrutinize along gradients of management. A step towards analyzing the impact of forest management on biodiversity is...     

Swimming Patterns Associated with Foraging in Phylogenetically and Ecologically Diverse American Weakly Electric Teleosts (Gymnotiformes)

The backwards swimming behavior exhibited by American weakly electric fishes (Gymnotiformes) is thought to be an important component of foraging, particularly in the electrolocation of prey items. Previous studies of Eigenmannia virescens and Apteronotus albifrons have shown that backwards swimming appears to allow a fish to scan a potential prey item across its cutaneous electroreceptor array, then put itself in position for a short, forward lunge preceding ingestion. Adult gymnotiforms exhibit considerable variation in size, shape, and electric organ characteristics. For example, gymnotiforms produce either a wave or a pulse electric organ discharge (EOD). Given this variation, we ask whether the results reported previously can be completely generalized to all gymnotiforms. To address this question we observed the foraging patterns of phylogenetically and ecologically distinct gymnotiforms: three wave species, E. virescens, A. albifrons and Sternopygus macrurus; and three pulse species, Gymnotus carapo, Brachyhypopomus cf. brevirostris, and Rhamphichthys rostratus. Electric organ placement and body shape were also noted in these species to determine if morphological differences correlate with variations in foraging behaviors. Results demonstrate that following prey detection the wave species examined primarily swim backwards during prey approach, prior to lunging forward and ingesting prey. This result is similar to previous findings. In contrast, the pulse species examined detect, approach, and ingest prey primarily in the forward direction, swimming backwards only to reposition themselves.     

The Differential Expression of Sucrose Synthase in Relation to Diverse Patterns of Carbon Partitioning in Developing Cotton Seed

Developing cotton (Gossypium hirsutum L.) seed exhibits complex patterns of carbon allocation in which incoming sucrose (Suc) is partitioned to three major sinks: the fibers, seed coat, and cotyledons, which synthesize cellulose, starch, and storage proteins or oils, respectively. In this study we investigated the role of Suc synthase (SuSy) in the mobilization of Suc into such sinks. Assessments of SuSy gene expression at various levels led to the surprising conclusion that, in contrast to that found for other plants, SuSy does not appear to play a role in starch synthesis in the cotton seed. However, our demonstration of functional symplastic connections between the phloem-unloading area and the fiber cells, as well as the SuSy expression pattern in fibers, indicates a major role of SuSy in partitioning carbon to fiber cellulose synthesis. SuSy expression is also high in transfer cells of the seed coat facing the cotyledons. Such high levels of SuSy could contribute to the synthesis of the thickened cell walls and to the energy generation for Suc efflux to the seed apoplast. The expression of SuSy in cotyledons also suggests a role in protein and lipid synthesis. In summary, the developing cotton seed provides an excellent example of the diverse roles played by SuSy in carbon metabolism.     

Magnaporthe oryzae Populations Adapted to Finger Millet and Rice Exhibit Distinctive Patterns of Genetic Diversity, Sexuality and Host Interaction

In this study, host-specific forms of the blast pathogen Magnaporthe oryzae in sub-Saharan Africa (SSA) were characterised from distinct cropping locations using a combination of molecular and biological assays. Finger millet blast populations in East Africa revealed a continuous genetic variation pattern and lack of clonal lineages, with a wide range of haplotypes. M. oryzae populations lacked the grasshopper (grh) element (96%) and appeared distinct to those in Asia. An overall near equal distribution (47-53%) of the mating types MAT1-1 and MAT1-2, high fertility status (84-89%) and the dominance of hermaphrodites (64%) suggest a strong sexual reproductive potential. Differences in pathogen aggressiveness and lack of cultivar incompatibility suggest the importance of quantitative resistance. Rice blast populations in West Africa showed a typical lineage-based structure. Among the nine lineages identified, three comprised ~90% of the isolates. Skewed distribution of the mating types MAT1-1 (29%) and MAT1-2 (71%) was accompanied by low fertility. Clear differences in cultivar compatibility within and between lineages suggest R gene-mediated interactions. Distinctive patterns of genetic diversity, sexual reproductive potential and pathogenicity suggest adaptive divergence of host-specific forms of M. oryzae populations linked to crop domestication and agricultural intensification.