Colony Area Research Articles

Anthropogenic impact is negatively related to coral health in Sicily (Mediterranean Sea)

Shallow-water marine organisms are among the first to suffer from combined effects of natural and anthropogenic drivers. The orange coral Astroides calycularis is a shallow-water bioconstructor species endemic to the Mediterranean Sea. Although raising conservation interest, also given its special position within the Dendrophylliidae, information about the threats to its health is scant. We investigated the health status of A. calycularis at five locations in northwestern Sicily along a gradient of cumulative human impact and the most probable origin of the threats to this species, including anthropogenic land-based and sea-based threats. Cumulative human impact appeared inversely related to the performance of A. calycularis at population, colony, and polyp levels. Sea-based human impacts appeared among the most likely causes of the variation observed. The reduction in polyp length can limit the reproductive performance of A. calycularis, while the decrease of percent cover and colony area is expected to impair its peculiar feeding behaviour by limiting the exploitable dimensional range of prey and, ultimately, reef functioning. This endangered habitat-forming species appeared susceptible to anthropogenic pressures, suggesting the need to re-assess its vulnerability status. Creating microprotected areas with specific restrictions to sea-based human impacts could be the best practice preserve these bioconstructions.

Clustered or dispersed: testing the effect of sampling strategy to census burrow-nesting petrels with varied distributions at sub-Antarctic Marion Island

AbstractWe compared systematic and random survey techniques to estimate breeding population sizes of burrow-nesting petrel species on Marion Island. White-chinned (Procellaria aequinoctialis) and blue (Halobaena caerulea) petrel population sizes were estimated in systematic surveys (which attempt to count every colony) in 2009 and 2012, respectively. In 2015, we counted burrows of white-chinned, blue and great-winged (Pterodroma macroptera) petrels within 52 randomized strip transects (25 m wide, total 144 km). Burrow densities were extrapolated by Geographic Information System-derived habitat attributes (geology, vegetation, slope, elevation, aspect) to generate island-wide burrow estimates. Great-winged petrel burrows were found singly or in small groups at low densities (2 burrows ha−1); white-chinned petrel burrows were in loose clusters at moderate densities (3 burrows ha−1); and blue petrel burrows were in tight clusters at high densities (13 burrows ha−1). The random survey estimated 58% more white-chinned petrels but 42% fewer blue petrels than the systematic surveys. The results suggest that random transects are best suited for species that are widely distributed at low densities, but become increasingly poor for estimating population sizes of species with clustered distributions. Repeated fixed transects provide a robust way to monitor changes in colony density and area, but might fail to detect the formation/disappearance of new colonies.

Characterization of Growth and Virulence of Five Nigerian Isolates of Entomopathogenic Fungi Using Galleria mellonella Larvae for Pathogenicity Testing

Entomopathogenic fungi (EF) are naturally occurring insect population regulators, with several species that are exploited as biocontrol agents against insect pests. Five EF consisting of two strains of Isaria farinosa, (IF-I and IF-II) and one strain each of Metarhizium anisopliae, Beauveria bassiana and Entomophaga sp. (Sensu lato) were isolated from soil using Tribolium castaneum (Coleoptera: Tenebrionidae) (Herbst) larvae as bait. The isolates were cultured on standard Potato Dextrose Agar (PDA) (Sigma-Aldrich, UK) and identified based on phenotypic appearance and micro-morphology. Growth rates (mm day-1), number of conidia per cm2 colony area after incubation for 14 days at ambient temperature (25±2°C), viability of conidia (% germination), based on 24-hours incubation period and virulence of the infective conidia against Galleria mellonella were evaluated. The data on growth was subjected to analysis of Variance (ANOVA) procedure and means were separated using Tukeys Honestly Significant Difference (P=0.05). The number of conidia produced by Entomophaga sp was (7.0×105 conidia cm 2 per colony area), while the isolate of M. anisopliae produced (5.2×104 conidia cm2 per colony area). The number of conidia produced by the two isolates of I. farinosa, IF-I and IF-II and B. bassiana were 9.4×104, 7.2×104 and 2.1×105 conidia cm2 per colony area respectively. Eighty percent of Entomophaga sp conidia germinated after incubating for 24 hours at 25°C while 100% germination occurred in the other fungal isolates. There were statistically significant variabilities in the rates of growth of the EF isolates F(4,2.064) =12.97, P=0.001. The B. bassiana isolate had the fastest growth rate, with statistically significant value of 3.3 mm day-1. The rates of growth of the two I. farinosa isolates: IF-I, IF-II and M. anisopliae were comparable, being 1.53, 1.4 and 1.28 mm day-1 respectively, without statistically significant difference. The growth rate of Entomophaga sp was 2.0 mm day-1, which was significantly higher than the growth rates of I. farinosa and M. anisopliae. The mean percentage mortality values of, G. mellonella larvae treated with 1×108 conidia ml-1 of the infective conidia of I. farinosa, IF-I, IF-II, M. anisopliae, after five days were 70, 60, 60% respectively while Entomophaga sp and B. bassiana caused 50% mortality. The results suggest that the five isolates examined can potentially be developed into experimental formulations and tested against important horticultural pests in future studies.

Social attraction used to establish Caspian tern nesting colonies in San Francisco Bay

Conservation of colonial waterbird breeding populations often includes restoring historic nesting habitat or establishing new nesting habitat in protected areas. However, colonization of new or restored nesting habitat may be hindered by the lack of social cues from nesting conspecifics to attract prospecting birds. Social attraction, whereby decoys and colony sound recordings are used to mimic active nesting colonies, has been used successfully to establish waterbird nesting colonies throughout the world. We constructed islands, modified the substrate so that it was attractive to nesting Caspian terns (Hydroprogne caspia), and then used social attraction to establish nesting colonies within two managed ponds in San Francisco Bay, California where Caspian terns had not previously nested. During the 2015–2017 breeding seasons, we deployed decoys of adult Caspian terns, broadcasted colony sound recordings, and monitored Caspian tern response. Caspian terns formed nesting colonies within weeks of social attraction deployment at each of the two ponds in 2015, and the size of these colonies increased in each subsequent year of the study. In 2017, the final year of the study, we estimated a minimum of 501 breeding pairs between the two colonies, making them two of the three largest Caspian tern colonies in the San Francisco Bay estuary. In total, these two colonies produced 1343 nests and 531 fledglings over the three-year study period. Nest densities were low (mean: 0.29 nests/m2 of active colony area) compared to other studies, and greater than 80% of the modified island habitat remained unused by nesting Caspian terns in 2017, suggesting that there is additional space for future colony growth. The successful establishment of two of the largest Caspian tern nesting colonies in the San Francisco Bay estuary in just three years demonstrates the potential of using island construction and habitat modifications, combined with social attraction measures to establish waterbird nesting colonies.

The Analysis of In Vivo Aging in Human Bone Marrow Mesenchymal Stromal Cells Using Colony-Forming Unit-Fibroblast Assay and the CD45lowCD271+ Phenotype

Uncultured mesenchymal stromal cells (MSCs) are increasingly used in therapies; however, the effects of donor age on their biological characteristics and gene expression remain unclear. The aim of this study was to investigate age-related changes in bone marrow (BM) MSCs following minimal or no culture manipulation. Iliac crest BM was aspirated from 67 healthy donors (19-89 years old) and directly used for the colony-forming unit-fibroblast (CFU-F) assay or CD45lowCD271+ cell enumeration. The colonies were analysed for colony area and integrated density (ID) when grown in standard MSC media or media supplemented with human serum from young (YS) or old (OS) donors. There was a notable age-related decline in the number of MSCs per millilitre of BM aspirate revealed by the CFU-F assay (r = −0.527, p < 0.0001) or flow cytometry (r = −0.307, p = 0.0116). Compared to young donors (19-40 years old), colony IDs were significantly lower in older donors (61-89 years old), particularly for smaller-sized colonies (42% lower, p < 0.01). When cultured in media supplemented with OS, young and old donor MSCs formed colonies with lower IDs, by 21%, p < 0.0001, and 27%, p < 0.05, respectively, indicating the formation of smaller sparser colonies. No significant differences in the expression of selected adipogenic, osteogenic, stromal, and bone remodelling genes as well as CD295, CD146, CD106, and connexin 43 surface molecules were found in sorted CD45lowCD271+ MSCs from young and old donors (n = 8 donors each). Altogether, these results show similar trends for age-related decline in BM MSC numbers measured by the CFU-F assay and flow cytometry and reveal age-related effects of human serum on MSC colony formation. No significant differences in selected gene expression in uncultured CD45lowCD271+ MSCs suggest that old donor MSCs may not be inferior in regard to their multipotential functions. Due to large donor-to-donor variation in all donor groups, our data indicate that an individual's chronological age is not a reliable predictor of their MSC number or potency.

Differential responses to chemical cues correlate with task performance in ant foragers

Division of labor in social insects has been explained by response threshold models which are based on differential responses to task-specific stimuli. In the present study, we argue that other types of stimuli, such as location-related cues, which are correlated with but not directly linked to task performance, may be significant. Using the black garden ant Lasius niger as a model, we focused on three groups of workers that perform extranidal tasks: (1) scouts, which explore new and unmarked areas remote from the nest; (2) patrollers, which are not recruited by other ants, but nonetheless walk outside in the nest vicinity; and (3) recruits, which are temporary foragers whose exit is triggered by recruitment. We used standardized tests to investigate, in a context-independent way, whether differences in task performance by these three groups could be correlated to intrinsic differences in their responsiveness to trail pheromone or to nest-related stimuli such as the presence of nestmates or colony odor. Overall, we found that the task profile of workers was correlated neither with their tendency to explore unmarked areas nor with their social attraction to nestmates. Scouts showed a lower attraction to colony odor and lower scores of trail following than recruits. Conversely, recruits were more attracted to colony chemical cues and showed lower response threshold to trail pheromone. Patrollers displayed behaviors between those of recruits and scouts. Our study thus shows that differences in ant responsiveness to location-related cues and recruitment trails contribute to the regulation of extranidal tasks in ants. Work organization in insect societies has been explained by models of differential response thresholds to stimuli that are directly linked to the performance of specific tasks. However, the task performance of individuals could also depend on their responsiveness to social and location-related cues that are correlated but not directly linked to these tasks. Using standardized context-independent tests, we found that scout ants, which explore unknown areas, display a lower responsiveness to colony area marking and trail pheromone. Conversely, recruits, which forage outside the nest only during food exploitation, are the most attracted to nestmates, colony area marking and trail pheromone. Patrollers display intermediate levels of attraction. Location-related cues could therefore play a role in determining the level of task performance by ants and should be taken into consideration in threshold models of task allocation.

Abstract 2844: In vitro recapitulation of in vivo obesity-promoted colorectal cancer growth using a patient-derived xenograft engineered tumor model

Abstract Strong epidemiological evidence links obesity to an increased risk of colorectal cancer (CRC). However, the precise molecular mechanisms underlying such an association have not been fully elucidated, partly due to the lack of physiologically relevant models. Here, we established a novel PEG-fibrinogen-based engineered tumor model using patient-derived xenograft (PDX) CRC co-cultured with 3T3-L1 adipocytes and an orthotopically implanted PDX CRC model of obesity. The PDX CRC cells were isolated from PDXs propagated subcutaneously in NOD-SCID mice and encapsulated within a biomimetic polymer, PEG-fibrinogen, to create 3D engineered PDX CRC tumors (3DePCCTs) or cultured in a standard 2D manner. We compared cell viability, colony area, and cell subpopulations within the 3DePCCTs and stiffness of the 3DePCCTs to the in vivo propagated tumors. A stage IV CRC tumor was employed in vivo and in vitro to study obesity-promoted tumor growth. Responsiveness of the 3DePCCTs to the growth promoting effects of obesity was investigated through continuous co-culture with insulin sensitive (IS) and resistant (IR) (treated with TNFα and 1% hypoxia) 3T3-L1 adipocytes (adipocytes replaced every 72 hrs). The responsiveness of the stage IV CRC PDX line was validated using an orthotopically implanted CRC model of obesity in which Rag1tm1Mom mice were fed a high fat Western diet + 4% sugar water (HFWD+S) to induce obesity or a chow diet to maintain a lean phenotype. The cells within the 3DePCCTs remained viable and the PDX-line dependent differential growth of tumor colony area within the 3DePPCTs recapitulated line-dependent difference in in vivo tumor growth. Based on flow cytometry, human (70±3%) and Cytokeratin 20+ (31±1) cell subpopulations within the 3DePCCTs were similar to the original in vivo tumor tissue and maintained over time, whereas supporting mouse stromal cells took over 2D cultured cells (n=3 batches). Stiffness of the 3DePCCTs was within the range of the in vivo tumor tissue stiffness (0.3 to3.6 KPa, n=3 tissues). In vitro adipocytes maintained IR for at least 72 hrs based on significantly higher MCP1 (at least 10 folds) and lower GLUT4 (maximally 0.1 fold) (n=3 batches). The in vitro coculture model revealed a significantly (p &amp;lt; 0.05) greater number of cancer cell colonies within 3DePCCTs after 8 days of co-culture with IR adipocytes compared to IS adipocytes and this difference increased through day 29. In the in vivo model, a significant (p &amp;lt; 0.05) greater than 2-fold increase in weight of PDX CRC tumors grown in mice fed the HFWD+S diet was observed. We have established the ability to maintain PDX CRC cells in 3D culture long-term (29 days) and generated a novel in vitro obesity-mimetic engineered tumor model that recapitulated the growth promoting effects of the in vivo orthotopic, IR tumor microenvironment and could be used to examine mechanistic questions and therapeutic targets. Citation Format: Iman Hassani, Benjamin Anbiah, Bulbul Ahmed, Nicole L. Habbit, Michael W. Greene, Elizabeth A. Lipke. In vitro recapitulation of in vivo obesity-promoted colorectal cancer growth using a patient-derived xenograft engineered tumor model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2844.

THE EFFECT OF MAGNETIC FIELD ON ANTIBIOTIC INHIBITION FOR Escherichia coli AND Bacillus sp.

This study was aimed to test the growth of bacteria Escherichia coli (E. coli) and Bacillus sp. which were exposed to magnetic fields. In the first stage of the study, the effect of magnetic fields on the growth of E. coli and Bacillus sp were observed. The futher study was aimed to evaluate the effect of magnetic field on antibiotic sensitivity againts the growth of E. coli and Bacillus sp. The magnetic fields treatments were 0.0 mT (control), 0.1 mT, 0.2 mT, 0.3 mT which were exposed for 10 hours for each treatment. Five antibiotics (trimethoprim, ampicillin, nalidixic acid, streptomycin and chloramphenicol) were used for each bacteria. The result showed that the magnetic field did not influence the colony growth of E.coli, but in Bacillus sp. was seen the increasing of colony area in magnetic field of 0.1 mT and 0.2 mT compared with control treatment. Antibiotic of trimethoprim, nalidixic acid, and ampicillin increase the growth inhibition of E. coli when the bacteria have been exposed to 0.1 mT; 0.2 mT; 0.3 mT magnetic field for 10 minutes. The inhibition by streptomycin and chloramphenicol antibiotic on E. coli did not affected by magnetic field exposure. The inhibition of Bacillus sp by trimethoprim and ampicillin increased when the bacteria have been exposed to 0.2 mT and 0.3 mT magnetic field for 10 minutes. The inhibition of nalidixic acid, streptomycin and chloramphenicol to Bacillus sp. did not affected by the magnetic field exposure.

Bahasa Indonesia

The leaves of some plants have been proved to suppress the development of plant diseases caused by pathogens. The study aimed to determine the water decoction of leaves to suppress the growth of S. rolfsii caused stem rot on peanuts in vitro. The study was conducted in the Laboratory of Phytopathology Departement of Plant Pest and Disease Faculty of Agriculture, Andalas University, from May-July 2015. The experimental design was a Randomized Complete Design (RCD) with seven treatments and six replications. The treatments were control, water decoction of Annona squamosa, Impatiens balsamina, Eclipta alba, Cymbopogon citratus and Tithonia diversifolia with concentration of 0,5% and fungicide with tebukonazol active ingredient at a concentration of 0,1%. Variables observed were macroscopic fungal culture, colony area, wet and dry weight of colonies. Data were analyzed by using ANOVA and DNMRT at a 5% of significance level.. The results showed that all water decoctions of plant leaves were able to suppress the growth of S. rolfsii. The most active of the water decoction was from T. diversifolia with suppression to colony area reached 77,32%,&nbsp; and wet and dry weight were 77,24% and 84,66%, respectively.

Identification and characterization of iPS clones via automated live-imaging and in-process analysis for quality control using high throughput robotic system

Background & Aim Induced pluripotent stem (iPS) cells are being developed for a broad range of research and therapeutic applications. However, reprogrammed iPS clones are inevitably heterogeneous. Current value judgements are made by visual inspection and manual selection. These methods are prone to large variation and lack the standardization or scalability needed for clinical translation. The goal of this work is to develop and validate Cell XTM, a robust robotic platform that will enable automated, and standardized iPS cell fabrication. Methods, Results & Conclusion We used DF6-9-9T.B hiPSC cell line, reprogrammed skin fibroblasts and peripheral blood mononuclear cells to develop our image processing parameters and picking and weeding protocols. To define and quantify critical quality attributes (CQAs) of “completely” reprogrammed iPS cells in systematic repeatable and reproducible manner, the Cell XTMPlatform is integrated with ColonyzeTM4.0, a very user-friendly WindowsTM-based automated quantitative cell and colony analysis software. The principles and nomenclature enabling this approach are outlined in ASTM Standard F2944-12. To automate manipulation of iPS cells in rapid, precise, repeatable and rigorously documented manner, the Cell XTMdevice integrates imaging, cell-manipulation (biopsy, pick, weed), fluid handling, and motion control systems. Using the Cell XTMgraphical user-interface, imaging, media changes and automated image processing were performed as illustrated in Figure 1. Picking operations were effective, and transplanted cells continued to proliferate effectively with morphology that is unchanged from that of the original colony. Automated image processing will display output metrics (colony area, the x,y,z-centroid for each colony, colony density, roundness, perimeter etc), as well as highlight the periphery of individual colonies or cell boundaries in the montage image. Based on these metrics, one can quantitatively define the cells or colonies of interest and selectively pick and transfer the cells for future experiments. The Cell XTMPlatform provides an integrated system of automated quantitative cell and colony imaging and analysis as well as tools for precision manipulation (biopsy, picking and weeding) driven by quantitative protocols that objectively determine the CQAs for repeatable, reproducible and quality iPS cell manufacturing.

Selective colony area method for heterogeneous patient-derived tumor cell lines in anti-cancer drug screening system.

We aimed to establish a fluorescence intensity-based colony area sweeping method by selecting the area of highest viability among patient-derived cancer cells (PDC) which has high tumor heterogeneity. Five gastric cancer cell lines and PDCs were screened with 24 small molecule compounds using a 3D micropillar/microwell chip. 100 tumor cells per well were immobilized in alginate, treated with the compounds, and then stained and scanned for viable cells. Dose response curves and IC50 values were obtained based on total or selected area intensity based on fluorescence. Unlike homogeneous cell lines, PDC comprised of debris and low-viability cells, which resulted in an inaccurate estimation of cell viability using total fluorescence intensity as determined by high IC50 values. However, the IC50 of these cells was lower and accurate when calculated based on the selected-colony-area method that eliminated the intensity offset associated with the heterogeneous nature of PDC. The selected-colony-area method was optimized to accurately predict drug response in micropillar environment using heterogeneous nature of PDCs.

Threshold responses of grassland and sagebrush birds to patterns of disturbance created by an ecosystem engineer

Burrowing mammals play a role in rangeland disturbance worldwide, enhancing habitat for certain species while negatively affecting others. However, little is known concerning effects of disturbance spatial pattern on co-occuring fauna. In the North American Great Plains, colonial black-tailed prairie dogs (Cynomys ludovicianus) may enhance habitat for one suite of birds while degrading habitat for others. We examined the influence of prairie dogs on birds in a mosaic grassland–shrubland landscape. We evaluated how birds associated with shortgrass, midgrass, and sagebrush (Artemisia spp.) plant communities respond to spatial pattern of prairie dog disturbance and identified thresholds where abundance changes. We surveyed bird abundance on prairie dog colonies of varying sizes and shapes, across colony edges into undisturbed habitat, and within undisturbed sagebrush in northeastern Wyoming. We modeled species responses to colony presence, distance to colony edge, and total area and edge density of colonies at four spatial scales (100 m, 225 m, 500 m, 1000 m). Sagebrush specialists like Brewer’s sparrow (Spizella breweri) and sage thrasher (Oreoscoptes montanus) were 4.5 times more abundant in undisturbed shrublands. Conversely, the shortgrass-specialist mountain plover (Charadrius montanus) was abundant on colonies but showed a non-linear response to colony edge, increasing in abundance up to 600 m from edges then declining further towards colony cores. While some species may be broadly intolerant to disturbance, disturbance-dependent birds can display a “goldilocks syndrome” relative to disturbance size. As such, management for multiple species of conservation concern can be optimized relative to other goals by identifying thresholds associated with the effect of disturbance.

Investigating a non-destructive alternative for a preliminary evaluation of fungal growth in solid state fermentations

Solid state fermentation (SSF) is an ancient technique which keeps attracting the attention of the food and biotechnology industries; however, a direct quantification of microbial biomass is still a fundamental challenge in this type of processes. Typically, growth is measured using indirect and destructive methods which do not allow a continuous evaluation of the evolution of microbial biomass within a single system. This article presents a non-destructive, quick and simple technique, based on digital imaging analysis (DIA) for the evaluation of growth in SSF laboratory experiments. DIA uses computational analysis of images from a SSF to measure areas and colour changes on a surface. The method can then be used to monitor microbial growth by assigning quantitative values for the growth of filamentous fungi. Firstly, studies on agar plates are used for the description of the method and to illustrate how it can be used to monitor fungal colony areas and densities. Following that, agro-industrial residues are used to demonstrate the application of the technique. DIA proved to be a practical and inexpensive tool to measure colony areas and densities. Furthermore, it is a non-destructive and non-intrusive method, which means that the evaluation of growth can be achieved within a single system.

Identification and application of a fungal biocontrol agent Cladosporium cladosporioides against Bemisia tabaci

The entomopathogenic fungus Cladosporium cladosporioides is a potential candidate for biocontrol of insect pests. We isolated a strain of C. cladosporioides BOU1 from an infected brown plant hoper (BPH) of rice and characterized it using morpho-physiological and molecular analyses. Internal transcribed spacer regions and intervening 5.8S rRNA gene (ITS) sequencing and morphopathogenic analyses confirmed that BOU1 is a strain of C. cladosporioides. To select the suitable medium for this fungus, a single condium of BOU1 was grown in potato dextrose agar (PDA), potato dextrose agar with yeast (PDAY), Sabouraud dextrose agar (SDA) and synthetic nutrient-poor agar (SNA) media. The suitable medium for this fungal isolate was determined by fungal growth (colony area and conidiogenesis), and enzymatic activities (protease and lipase). The fungal growth parameters including enzymatic activities showed that the PDA medium is most suitable culture medium for C. cladosporioides. Finally, the pathogenicity of this fungal isolate was evaluated against whitefly, Bemisia tabaci through direct contact toxicity assay on eggplant leaves by dipping under laboratory conditions. The BOU1 strain caused mortality in B. tabaci in a dose-dependent manner, the highest mortality being 71% at 1 × 108 conidia/mL. To the best of our knowledge, this is the first report of isolation and molecular characterization of an entomopathogenic fungus C. cladosporioides from a BPH of rice. This study suggests that BOU1 is a potential candidate for biological control of whitefly for the promotion of sustainable agriculture.

Effect of water temperature during ultrasonic denture cleaning.

Denture plaque is a biofilm composed of various microorganisms aggregated with saliva. Various denture cleansers and cleaning apparatuses have been developed and studied. However, the optimum water temperature for denture cleaning is unknown. Therefore, the present study investigated the effects of water temperature during ultrasonic denture cleaning. In vitro, resin disks with artificial Candida albicans biofilm were pressed onto Candida GE media after ultrasonic cleaning with water at different temperatures for 5 min. The media were subsequently cultured at 37°C for 24 h. The colonies formed were observed and colony areas were quantified using ImageJ software (US National Institutes of Health, Bethesda, MD, USA). In situ, the bacterial count and degree of cleanliness on the tissue surface of maxillary dentures were measured before and after ultrasonic cleaning with water at different temperatures for 5 min. Changes in bacterial counts and cleanliness were calculated for each temperature. The ratio of the area occupied by bacterial colonies in vitro and reduction rates in situ after cleaning with warm water were markedly less than those observed after cleaning with cold water. Therefore, ultrasonic denture cleaning with warm water is more effective.

Supplementation of Glial Cell Line-Derived Neurotrophic Factor, Fibroblast Growth Factor 2, and Epidermal Growth Factor Promotes Self-Renewal of Putative Buffalo (Bubalus bubalis) Spermatogonial Stem Cells by Upregulating the Expression of miR-20b, miR-21, and miR-106a.

In this study, we investigated the effect of glial cell line-derived neurotrophic factor (GDNF), fibroblast growth factor (FGF) 2, and epidermal growth factor (EGF) on the expression of some self-renewal-related microRNAs (miRs) in putative buffalo spermatogonial stem cells (SSCs). The SSCs were cultured on a buffalo Sertoli cell feeder layer, colony formation was observed between 7 and 10 days. The SSC colonies expressed markers specific for undifferentiated type A spermatogonia and pluripotency markers. After 15 days of initial culture, the colonies were subcultured as treatment (supplemented with 20 ng mL-1 GDNF +10 ng mL-1 FGF2 + 10 ng mL-1 EGF) and control groups. The number and area of SSC colonies were significantly (p < 0.05) higher in the treatment group than in the control group. The relative abundance of miR-20b, miR-21, and miR-106a in SSCs supplemented with growth factors was significantly higher (p < 0.001) than that in the control. The results indicate that supplementation of SSC culture medium with growth factors (GDNF, FGF2, and EGF) may promote the expression of miR-20b, miR-21, and miR-106a, which is essential for self-renewal and maintenance of SSCs.

Individual and population level effects of ocean acidification on a predator-prey system with inducible defenses: bryozoan-nudibranch interactions in the Salish Sea

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 607:1-18 (2018) - DOI: https://doi.org/10.3354/meps12793 FEATURE ARTICLE Individual and population level effects of ocean acidification on a predator-prey system with inducible defenses: bryozoan-nudibranch interactions in the Salish Sea Sasha K. Seroy1,2,*, Daniel Grünbaum1,2 1School of Oceanography, University of Washington, Seattle, Washington 98105, USA 2Friday Harbor Laboratories, University of Washington, Friday Harbor, Washington 98250, USA *Corresponding author: sseroy@uw.edu ABSTRACT: Ocean acidification (OA) from increased oceanic CO2 concentrations imposes significant physiological stresses on many calcifying organisms. OA effects on individual organisms may be synergistically amplified or reduced by inter- and intraspecies interactions as they propagate up to population and community levels, altering predictions by studies of calcifier responses in isolation. The calcifying colonial bryozoan Membranipora membranacea and the predatory nudibranch Corambe steinbergae comprise a trophic system strongly regulated by predator-induced defensive responses and space limitation, presenting a unique system to investigate OA effects on these regulatory mechanisms at individual and population levels. We experimentally quantified OA effects across a range of pH from 7.0 to 7.9 on growth, calcification, senescence and predator-induced spine formation in Membranipora, with or without waterborne predator cue, and on zooid consumption rates in Corambe at Friday Harbor Laboratories, San Juan Island, WA. Membranipora exhibited maximum growth and calcification at moderately low pH (7.6), and continued spine formation in all pH treatments. Spines reduced Corambe zooid consumption rates, with lower pH weakening this effect. Using a spatially explicit model of colony growth, where colony area serves as a proxy for colony fitness, we assessed the population-level impacts of these experimentally determined individual-level effects in the context of space limitation. The area-based fitness costs associated with defense measured at the individual level led to amplified effects predicted for the population level due to competition. Our coupled experimental and modeling results demonstrate the need to consider population-level processes when assessing ecological responses to stresses from changing environments. KEY WORDS: Predator-prey interactions · Ocean acidification · Inducible defenses · Space competition · Modeling · Membranipora membranacea · Corambe steinbergae Full text in pdf format Information about this Feature Article Supplementary material NextCite this article as: Seroy SK, Grünbaum D (2018) Individual and population level effects of ocean acidification on a predator-prey system with inducible defenses: bryozoan-nudibranch interactions in the Salish Sea. Mar Ecol Prog Ser 607:1-18. https://doi.org/10.3354/meps12793 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 607. Online publication date: December 06, 2018 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2018 Inter-Research.

Cell colony counter called CoCoNut.

Clonogenic assays are powerful tools for testing cell reproductive death after biological damage caused by, for example, ionizing radiation. Traditionally, the methods require a cumbersome, slow and eye-straining manual counting of viable colonies under a microscope. To speed up the counting process and minimize those issues related to the subjective decisions of the scoring personnel, we developed a semi-automated, image-based cell colony counting setup, named CoCoNut (Colony Counter developed by the Nutech department at the Technical University of Denmark). It consists in an ImageJ macro and a photographic 3D-printed light-box, conceived and demonstrated to work together for Crystal Violet-stained colonies. Careful attention was given to the image acquisition process, which allows background removal (i.e. any unwanted element in the picture) in a minimally invasive manner. This is mainly achieved by optimal lighting conditions in the light-box and dividing the image of a flask that contains viable colonies by the picture of an empty flask. In this way, CoCoNut avoids using aggressive background removal filters that usually lead to suboptimal colony count recovery. The full method was tested with V79 and HeLa cell survival samples. Results were compared to other freely available tools. CoCoNut proved able to successfully distinguish between single and merged colonies and to identify colonies bordering on flask edges. CoCoNut software calibration is fast; it requires the adjustment of a single parameter that is the smallest colony area to be counted. The employment of a single parameter reduces the risk of subjectivity, providing a robust and user-friendly tool, whose results can be easily compared over time and among different bio-laboratories. The method is inexpensive and easy to obtain. Among its advantages, we highlight the possibility of combining the macro with a perfectly reproducible 3D-printed light-box. The CoCoNut software and the 3D-printer files are provided as supporting information (S1 CoCoNut Files).

A new use of technology to solve an old problem: Estimating the population size of a burrow nesting seabird.

Estimating the population of burrow-nesting seabirds is a challenging task, as human presence in the colony creates disturbances and can damage burrows and occupants. Here, we present a novel method using aerial photographs taken with Unmanned Aerial Vehicles (UAVs) to estimate the population size of a burrow-nesting seabird, the Black-vented Shearwater (Puffinus opisthomelas), on Natividad Island, Mexico. Our results provide a census of burrows in the colony, with very low detection error (5.6%). This is greater accuracy compared to other methods based on extrapolating results from sample plots to total colony area. We then combined this burrow census with ground truth data on occupancy to estimate population size. We obtained a population estimate of 37,858 and 46,322 breeding pairs for 2016 and 2017 respectively. The proposed method provides a cost effective and repeatable approach for monitoring numbers of burrows occupied in a colony, thereby enabling easier and faster estimates of population trends. We suggest this method can be valid for other burrow-nesting species in habitats without dense vegetation cover.

Influence of mitochondrial DNA loss on the development of complex structured colonies of SK1 strains of yeast Saccharomyces cerevisiae

Aim. Determine the effect of mitochondrial DNA loss on the formation of complex yeast colonies of Saccharomyces cerevisiae. Methods. Development of giant colonies of the parent strain SK1 (rho+) and the "petit" strain SK1p, which lost mtDNA (rho0 mutation), was observed for 40 days,. To find out zones of cell death in colonies, both strains were cultured on solid YPD media containing dyes that accumulate in dead cells. The survival of the cells within colony was estimated by the ability to create microcolonies. Results. The loss of mitochondrial DNA in SK1p cells led to a decrease in colony area and to simplification of colony morphology on the YPD medium. When SK1p colonies were cultivated on media with addition of dyes, bright spot was formed in the center due to the dyes accumulation in dead cells. At the same time, parent strain developed a uniform insignificant coloration. Conclusions. rho0 mutation in SK1p yeast strain Saccharomyces cerevisiae led to a significant simplification of complex colony structure that formed on the nutrient medium YPD. The mitochondrial DNA loss in strain SK1p results in an accelerated cell death in the center of colony on YPD.Keywords: Saccharomyces cerevisiae, rho0, colonies, cell survival.