Use Of Organisms Research Articles

The seed germination and seedling phytotoxicity of decabromodiphenyl ethane to tall fescue under citric acid amendment.

The novel brominated flame retardant decabromodiphenyl ethane (DBDPE) has biological toxicity, persistence, long-range migration and bioaccumulation ability. However, there is currently little research on the phytotoxicity of DBDPE in plants. The perennial herbaceous plant tall fescue (Festuca elata Keng ex E. B. Alexeev) was selected as the model organism for use in seed germination experiments, and the phytotoxicity of DBDPE in the soil of tall fescue was studied. The results indicated that DBDPE had a significant effect on the germination and growth of tall fescue seedlings. Citric acid reduced the stress caused by DBDPE in plants, effectively alleviating the phytotoxicity of DBDPE in tall fescue. The root vitality and protein content significantly increased after the application of citric acid, increasing by 74.93-183.90%, 146.44-147.67%, respectively. The contents of proline and soluble sugars significantly decreased after the application of citric acid, decreasing by 45.18-59.69% and 23.03%, respectively (P < 0.05). There was no significant difference in superoxide dismutase (SOD) or peroxidase (POD) activity in tall fescue seedlings, and the catalase (CAT) activity and malondialdehyde (MDA) content were significantly lower after the application of citric acid, decreasing by 64.62-67.91% and 29.10-49.80%, respectively (P < 0.05). Tall fescue seedlings bioaccumulated DBDPE, with biological concentration factors (BCFs) ranging from 4.28 to 18.38 and transfer factors (TFs) ranging from 0.43 to 0.54. This study provides theoretical support for the study of the toxicity of DBDPE to plants and offers a research foundation for exploring the phytoremediation of DBDPE-contaminated soil by tall fescue.

Concentration- and time-dependent behavioural effects of ethanol on Lumbriculus variegatus.

Ethanol is one of the most widely used drugs in the world. Ethanol induces profound physiological and behavioural responses in invertebrate model organisms, such as Caenorhabditis elegans and Drosophila melanogaster. Lumbriculus variegatus (Annelida, Oligochaete) is an aquatic worm which shows behavioural responses to common drugs and thus is potentially useful in pharmacological research. The effects of ethanol are unknown in this organism. In this study, we examine the effects of acute exposure to ethanol (0-500 mM) on the stereotypical movements and locomotor activity of L. variegatus and examine the concentration- (0-500 mM) and time-dependent (0-210 min) effects of ethanol in L. variegatus. We show that ≥250 mM ethanol reversibly reduced the ability of tactile stimulation to elicit stereotypical movements, namely body reversal and helical swimming and locomotor activity (p < 0.05, N = 8). We also found that 2 min of exposure to ≥250 mM ethanol rapidly induces steady-state hypokinesis (p < 0.05, N = 11) and confirm ethanol absorption into L. variegatus tissues. Additionally, we also observed acute ethanol tolerance after 150 min of exposure to 500 mM ethanol (p < 0.05, N = 24). This study is the first to report the behavioural effects of ethanol in L. variegatus. Our results show that this is a model organism for use in ethanol studies, providing further evidence for its utility in pharmacological research.

Microbial agents for the control of ticks Rhipicephalus microplus.

Ticks are ectoparasites responsible for the transmission of various pathogens to vertebrates. They represent one of the major threats to livestock production worldwide due to their impact on the health, production and welfare of livestock destined for human consumption. The development of resistance to the main families of ixodicides used for their control has led to the search for new alternatives, where microbial control is an option. The use of microbial control agents against the tick Rhipicephalus microplus is reviewed in this paper. Bacteria such as Bacillus thuringiensis, Serratia marcescens and Staphylococcus spp. the nematodes Steinernema spp. and Heterorhabditis spp. as well as the fungi Metarhizium anisopliae and Beauveria bassiana are the most studied organisms for use as biological control agents against ticks. Laboratory, stable and field trials with free-living and parasitised ticks have shown that microbial agents can control both susceptible and ixodicide-resistant tick populations. However, multidisciplinary studies using novel tools like genomics, transcriptomics and proteomics should be carried out to understand the virulence factors which microbial agents use to induce pathogenesis and virulence in ticks. In addition, applied research will be carried out with the aim of improving techniques for large-scale application, as well as the improvement of cultivation, storage, formulation and application methods.

Development of Multiple Linear Regression Models for Predicting Chronic Iron Toxicity to Aquatic Organisms.

We developed multiple linear regression (MLR) models for predicting iron (Fe) toxicity to aquatic organisms for use in deriving site-specific water quality guidelines (WQGs). The effects of dissolved organic carbon (DOC), hardness, and pH on Fe toxicity to three representative taxa (Ceriodaphnia dubia, Pimephales promelas, and Raphidocelis subcapitata) were evaluated. Both DOC and pH were identified as toxicity-modifying factors (TMFs) for P. promelas and R. subcapitata, whereas only DOC was a TMF for C. dubia. The MLR models based on effective concentration 10% and 20% values were developed and performed reasonably well, with adjusted R2 of 0.68-0.89 across all species and statistical endpoints. Differences among species in the MLR models precluded development of a pooled model. Instead, the species-specific models were assumed to be representative of invertebrates, fish, and algae and were applied accordingly to normalize toxicity data. The species sensitivity distribution (SSD) included standard laboratory toxicity data and effects data from mesocosm experiments on aquatic insects, with aquatic insects being the predominant taxa in the lowest quartile of the SSD. Using the European Union approach for deriving WQGs, application of MLR models to this SSD resulted in WQGs ranging from 114 to 765 μg l-1 Fe across the TMF conditions evaluated (DOC: 0.5-10 mg l-1 ; pH: 6.0-8.4), with slightly higher WQGs (199-910 μg l-1 ) derived using the US Environmental Protection Agency (USEPA) methodology. An important uncertainty in these derivations is the applicability of the C. dubia MLR model (no pH parameter) to aquatic insects, and understanding the pH sensitivity of aquatic insects to Fe toxicity is a research priority. An Excel-based tool for calculating Fe WQGs using both European Union and USEPA approaches across a range of TMF conditions is provided. Environ Toxicol Chem 2023;00:1-15. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

The Role of Hsp70 in Adaptation to Adverse Conditions and Its Possible Medical Application.

In the present era of global warming and dramatically increased environmental pollution posing a threat to animal life, the understanding and manipulation of organisms' resources of stress tolerance is apparently a question of survival. Heat stress and other forms of stressful factors induce a highly organized response of organisms at the cellular level where heat shock proteins (Hsps) and in particular Hsp70 family of chaperones are among the major players in the protection from the environmental challenge. The present review article summarizes the peculiarities of the Hsp70 family of proteins protective functions being a result of many millions of years of adaptive evolution. It discusses the molecular structure and specific details of hsp70 gene regulation in various organisms, living in diverse climatic zones, with a special emphasis on the protective role of Hsp70 in adverse conditions of the environment. The review discusses the molecular mechanisms underlying Hsp70-specific properties that emerged in the course of adaptation to harsh environmental conditions. This review also includes the data on the anti-inflammatory role of Hsp70 and the involvement of endogenous and recombinant Hsp70 (recHsp70) in proteostatic machinery in various pathologies including neurodegenerative ones such as Alzheimer's and Parkinson's diseases in rodent model organisms and humans in vivo and in vitro. Specifically, the role of Hsp70 as an indicator of disease type and severity and the use of recHsp70 in several pathologies are discussed. The review discusses different roles exhibited by Hsp70 in various diseases including the dual and sometimes antagonistic role of this chaperone in various forms of cancer and viral infection including the SARS-Cov-2 case. Since Hsp70 apparently plays an important role in many diseases and pathologies and has significant therapeutic potential there is a dire need to develop cheap recombinant Hsp70 production and further investigate the interaction of externally supplied and endogenous Hsp70 in chaperonotherapy.

EFFECT OF TEMPERATURE ON REGENERATION OF Eisenia fetida

Earthworms are eucoelomate, vermiform and metamerically segmented animals belonging to Phylum Annelida. They are a powerful model organism for use in studying the mechanism of regeneration. Regeneration is a complex phenomenon to restore lost or damaged parts. Such kind of regeneration is naturally vested in earthworms and regeneration capability varies among different species. In this present study Eisenia fetida species was taken. Groups of earthworms were kept in different temperatures and their regeneration capability was examined. The earthworms were exposed to three different temperature ranges: below 24°c, 24°c - 30°c, and above 30°c. The earthworms those were exposed to low (&lt;24°c) and high (&gt;30°c) temperatures showed decreased rate of regeneration. This shows the influence of environmental factors on regeneration rate.

Engineered cells along with smart scaffolds: critical factors for improving tissue engineering approaches.

In this review, gene delivery and its applications are discussed in tissue engineering (TE); also, new techniques such as the CRISPR-Cas9 system, synthetics biologyand molecular dynamics simulation to improve the efficiency of the scaffolds have been studied. CRISPR-Cas9 is expected to make significant advances in TEin the future. The fundamentals of synthetic biology have developed powerful and flexible methods for programming cells via artificial genetic circuits. The combination of regenerative medicine and artificial biology allows the engineering of cells and organisms for use in TE, biomaterials, bioprocessingand scaffold development. The dynamics of protein adsorption at the scaffold surface at the atomic level can provide valuable guidelines for the future design of TE scaffolds /implants.

Improvement of cell-tethered cellulase activity in recombinant strains of Saccharomyces cerevisiae.

Consolidated bioprocessing (CBP) remains an attractive option for the production of commodity products from pretreated lignocellulose if a process-suitable organism can be engineered. The yeast Saccharomyces cerevisiae requires engineered cellulolytic activity to enable its use in CBP production of second-generation (2G) bioethanol. A promising strategy for heterologous cellulase production in yeast entails displaying enzymes on the cell surface by means of glycosylphosphatidylinositol (GPI) anchors. While strains producing a core set of cell-adhered cellulases that enabled crystalline cellulose hydrolysis have been created, secreted levels of enzyme were insufficient for complete cellulose hydrolysis. In fact, all reported recombinant yeast CBP candidates must overcome the drawback of generally low secretion titers. Rational strain engineering can be applied to enhance the secretion phenotype. This study aimed to improve the amount of cell-adhered cellulase activities of recombinant S. cerevisiae strains expressing a core set of four cellulases, through overexpression of genes that were previously shown to enhance cellulase secretion. Results showed significant increases in cellulolytic activity for all cell-adhered cellulase enzyme types. Cell-adhered cellobiohydrolase activity was improved by up to 101%, β-glucosidase activity by up to 99%, and endoglucanase activity by up to 231%. Improved hydrolysis of crystalline cellulose of up to 186% and improved ethanol yields from this substrate of 40-50% in different strain backgrounds were also observed. In addition, improvement in resistance to fermentation stressors was noted in some strains. These strains represent a step towards more efficient organisms for use in 2G biofuel production. KEY POINTS: • Cell-surface-adhered cellulase activity was improved in strains engineered for CBP. • Levels of improvement of activity were strain and enzyme dependent. • Crystalline cellulose conversion to ethanol could be improved up to 50%.

Monitoring life cycle stages of axenic cultures of in vitro produced Oscheius L8 MCB in semi-solid state and liquid state and comparative efficacy studies between in vitro and in vivo nematode production against Galleria mellonella

The emergence of entomopathogenic nematodes as biocontrol agents of insect pests has caused a shift of focus towards the use of in vitro methods for commercial production of these organisms for use in agricultural settings. In this study, Oscheius L8 MCB, an insecticidal nematode isolated from Brits in the North West Province of South Africa, was produced in vitro via axenic means in liquid and semi-solid states. Light microscopy was used to monitor and enumerate life cycle stages of this isolate, with special focus given to the yield of the insecticidal Infective juvenile (IJ) stage. Comparative dose–response assays were used to determine the efficacy of in vitro production of Oscheius L8 MCB versus in vivo production against Galleria mellonella. In vitro produced Oscheius L8 MCB consisted of four juvenile stages, with one of the juvenile stages being the non-feeding IJ stage. Adults stages comprised amphimictic males and females, and female hermaphrodites. The semi-solid state produced IJs in three yield peaks of 2.33 × 104 IJs/ml (SEM ± 1922 IJs/ml), 1.93 × 104 IJs/ml (SEM ± 2455 IJs/ml) and 1.92 × 104 IJs/ml (SEM ± 3542 IJs/ml) at days 6, 9 and 11 respectively. In contrast, the liquid state produced a single peak of 3.6 × 104 IJs/ml (SEM ± 1178 IJs/ml) at day 12. In vivo produced Oscheius L8 MCB established at least 50% G. mellonella larvae mortality 24 h post infection, at an infective IJ concentration of 25 IJ/100 µl compared to 0% (semi-solid) and 16.67% (liquid) larvae mortality established by in vitro produced Oscheius L8 MCB at the same concentration after 24 h. The number of IJs emerging from a larvae cadaver may be indicative of field coverage, efficacy, and field persistence. Larvae cadaver infected with in vivo produced IJs produced a maximum of 8.36 × 104 IJs/larvae (SEM ± 3900 IJs/larvae) in comparison to larvae cadaver infected with in vitro produced IJs, which produced maximums of 5.50 × 104 IJs/larvae (SEM ± 2527 IJs/larvae) and 4.44 × 104 IJs/larvae (SEM ± 1803 IJs/larvae) for liquid and semi-solid states respectively. The mortality and IJ emergence in larvae infected with semi-solid state and liquid state Oscheius L8 MCB varied according to infective IJ concentration. However, in conclusion, axenic in vitro culturing of Oscheius L8 MCB may reduce its efficacy against insect hosts.

UJI AKTIVITAS ANTIBAKTERI DAN ANTI-UV DARI EKSTRAK ETIL ASETAT ISOLAT JAMUR AFBK 5c YANG BERSIMBION DENGAN ASCIDIA Sigilina sp. DARI PERAIRAN PULAU BANGKA

Bioactive compounds are toxic compounds produced by organisms for use in self-defense from a wide variety of predators residing in their environment. The aim of the study was to test antibacterial activity and prove the UV-preventing effectiveness of the AFBK 5c mushroom isolate ethyl acetate extract that is in conjunction with ascidia. This research was conducted for 1 month in two locations, namely for antibacterial testing conducted in the Laboratory of Molecular Biology and Marine Pharmaceuticals, FPIK and for anti-UV testing conducted at the Pharmaceutical Laboratory, FMIPA, UNSRAT. The results showed that; This type of fungus that has been extracted and used is a fungus with the isolate code AFBK 5c This mushroom is a fungus that is connected with sigilina sp type ascidia. The rough extract of ascidia symbiont mushrooms is obtained from the process of meseration using ethyl acetate, then antibacterial testing of S. aureus and E. coli test bacteria and showing results such as antibacterial activity with an average value in S. aureus 09.00 and E. coli 11.05 mm which shows that there is antibacterial activity of AFBK 5c fungus isolate against E. coli and S. aureus test bacteria so that it can be said that the symbiont fungus has the potential as an ingredient. manufacture of antibacterial drugs. Furthermore, anti-UV testing, and the results of testing anti-UV compounds using rough extracts of AFBK 5c fungus isolates can produce absorption in UV-B (λ 290-320 nm) and UV-A (λ 320-400 nm) so that it has the potential to be used as an anti-UV material.Keywords: Bioactive Compound, Ascidia, Meceration, Antibacterial, Anti-UV

Shotgun Immunoproteomic Approach for the Discovery of Linear B-Cell Epitopes in Biothreat Agents Francisella tularensis and Burkholderia pseudomallei.

Peptide-based subunit vaccines are coming to the forefront of current vaccine approaches, with safety and cost-effective production among their top advantages. Peptide vaccine formulations consist of multiple synthetic linear epitopes that together trigger desired immune responses that can result in robust immune memory. The advantages of linear compared to conformational epitopes are their simple structure, ease of synthesis, and ability to stimulate immune responses by means that do not require complex 3D conformation. Prediction of linear epitopes through use of computational tools is fast and cost-effective, but typically of low accuracy, necessitating extensive experimentation to verify results. On the other hand, identification of linear epitopes through experimental screening has been an inefficient process that requires thorough characterization of previously identified full-length protein antigens, or laborious techniques involving genetic manipulation of organisms. In this study, we apply a newly developed generalizable screening method that enables efficient identification of B-cell epitopes in the proteomes of pathogenic bacteria. As a test case, we used this method to identify epitopes in the proteome of Francisella tularensis (Ft), a Select Agent with a well-characterized immunoproteome. Our screen identified many peptides that map to known antigens, including verified and predicted outer membrane proteins and extracellular proteins, validating the utility of this approach. We then used the method to identify seroreactive peptides in the less characterized immunoproteome of Select Agent Burkholderia pseudomallei (Bp). This screen revealed known Bp antigens as well as proteins that have not been previously identified as antigens. Although B-cell epitope prediction tools Bepipred 2.0 and iBCE-EL classified many of our seroreactive peptides as epitopes, they did not score them significantly higher than the non-reactive tryptic peptides in our study, nor did they assign higher scores to seroreactive peptides from known Ft or Bp antigens, highlighting the need for experimental data instead of relying on computational epitope predictions alone. The present workflow is easily adaptable to detecting peptide targets relevant to the immune systems of other mammalian species, including humans (depending upon the availability of convalescent sera from patients), and could aid in accelerating the discovery of B-cell epitopes and development of vaccines to counter emerging biological threats.

Genetic techniques for plant breeding

Genetic techniques for plant breeding

Lumbriculus variegatus: A novel organism for in vivo pharmacology education.

Pharmacology graduates require an understanding of both in vitro and in vivo drug responses but there has been a decline in animal use in pharmacology education over the last 30 years. To address this, we present the novel invertebrate model, Lumbriculus variegatus, for in vivo testing of drugs in a teaching environment. We have developed two novel behavioral assays: the stereotypical movement assay, which measures the effect of drugs on the ability of L. variegatus to perform stereotypical movements following tactile stimulation, and the free locomotion assay, which measures drug effects on unstimulated movement. We report the effects of compounds with diverse pharmacodynamic properties on L. variegatus using these assays. The ryanodine receptor antagonist, dantrolene, altered the unstimulated movement of L. variegatus at 5 μM, whereas stimulated movement was inhibited at ≥25 μM. Lidocaine, a voltage‐gated sodium channel blocker, and quinine, a nonselective sodium and potassium channel blocker, reduced both stimulated and unstimulated L. variegatus movement at ≥0.5 mM. Inhibitory effects of quinine persisted for up to 24 h after drug removal, whereas lidocaine effects were reduced 10 min after drug removal. Herein, we provide proof‐of‐concept utilization of L. variegatus as an organism for use in in vivo pharmacology education but without regulatory constraints or the need for specialized equipment and training.

Generation and Characterization of Transgenic Chlamydomonas reinhardtii Overexpressing the Novel Gene Cia7

The constant increase in environmental pollution, in particular heavy metal pollution is alarming. Cia7, the gene understudy has conserved cysteine residues. These residues could be involved in metal binding; and the CIA7 protein might be associated to metal homeostasis in Chlamydomonas reinhardtii. The successful overexpression of Cia7 in C. reinhardtii could enhance its metal tolerance. Current research in bioremediation and heavy metal pollution is present in the literature. However, there is limited research in this area that involves C. reinhardtii. Additionally, the function of CIA7 is still unknown. The core hypothesis is that CIA7 plays a role in metal tolerance and in metal binding. This research will attempt to address if CIA7 performs a role in C. reinhardtii’s tolerance to metal toxicity. The aim of this research is to characterize the Cia7 gene and to assess its potential role in metal homeostasis. The objectives of the research are (1) to overexpress CIA7 in C. reinhardtii, and (2) to compare cell growth, chlorophyll content and bioaccumulation of heavy metals in cc5013 mutant, cc4425 wild‐type and the selected transformants under the presence or absence of lead. The gene was overexpressed in wild‐type (WT) and mutant (MT) C. reinhardtii cells.WT and MT cells were subjected to lead (Pb) assays in order to find the optimum sub‐lethal concentration. Once the optimum sub‐lethal concentration was found, sub‐lethal assays were performed. The goal of the sub‐lethal assays was to observe the growth of transformants and to observe any difference in phenotype among cells with the overexpressed Cia7 gene, the WT and the MT when exposed to metal stress. To establish whether exposure to metal would affect chlorophyll biosynthesis, a chlorophyll content analysis was conducted. To measure lead bioaccumulation among the strains, inductively coupled plasma‐optical emission spectrometry (ICP‐OES) analysis was conducted. Lastly, cell density was recorded to measure and compare the growth of the different C. reinhardtii strains. Samples for all of these protocols were collected at different time intervals. The sub‐lethal concentration of lead, whereby a difference in growth was observed was at 1.5 mM Pb. Interestingly, there were colonies from the generated transformants that were found to be more lead tolerant at 1.5 mM compared to the wild‐type and the mutant strains. These colonies, the wild‐type and the mutant strains were subjected to a chlorophyll content analysis and bioaccumulation analysis to determine if there is any difference among them. Results from these experiments will be reported. The findings of this research could provide a basis to (1) use Cia7 as a biomarker for metal contamination, or to (2) make the CIA7 protein be overexpressed in C. reinhardtii or in another organism for use in phytoremediation.Support or Funding InformationA special thanks to my research mentor, Dr. R Ynalvez. Thank you to TAMIU Graduate Financial Assistance for my assistantship and to the Office of Research and Sponsored Projects for my summer 2019 fellowship. Thanks to Dr. M Ynalvez for the statistical analysis. Thank you to fellow lab mates for the support in this research.

Bioengineering a Future Free of Marine Plastic Waste

Plastic waste has reached epidemic proportions worldwide, and the production of plastic continues to rise steadily. Plastic represents a diverse array of commonly-used synthetic polymers that are extremely useful as durable, economically-beneficial alternatives to other materials; however, despite the wide-ranging utility of plastic, the increasing accumulation of plastic waste in the environment has had numerous detrimental impacts. In particular, plastic marine debris can transport invasive species, entangle marine organisms, and cause toxic chemical bioaccumulation in the marine food web. The negative impacts of plastic waste have motivated research on new ways to reduce and eliminate plastic. One unique approach to tackle the plastic waste problem is to turn to nature’s solutions for degrading polymers by leveraging the biology of naturally-occurring organisms to degrade plastic. Advances in metagenomics, next generation sequencing, and bioengineering have provided new insights and new opportunities to identify and optimize organisms for use in plastic bioremediation. In this review, we discuss the plastic waste problem and possible solutions, with a focus on potential mechanisms for plastic bioremediation. We pinpoint two key habitats to identify plastic-biodegrading organisms: 1) habitats with distinct enrichment of plastic waste, such as those near processing or disposal sites, and 2) habitats with naturally-occurring polymers, such as cutin, lignin, and wax. Finally, we identify directions of future research for the isolation and optimization of these methods for widespread bioremediation applications.

Stoichiometrically balanced nutrient management using a newly designed nutrient medium for large scale cultivation of Cyanobacterium aponinum

Cyanobacteria have tremendous potential to produce bioactive molecules, which makes them a highly lucrative organism for use in industrial applications. In the present study, the first commercial nutrient medium for Cyanobacterium aponinum is developed and a process for large scale cultivation of cyanobacteria is established by combining economical medium, pre-emptive nutrient feeding strategy, and semi-continuous mode (SCM) of cultivation. The parameters measured were growth in terms of OD750 biomass, total nitrogen, nitrate, and phosphorous. Results indicated 13% more biomass yield in urea-phosphoric acid medium (UPA), in comparison to blue-green medium (BG-11). Biomass concentration was 5.3 and 4.7 g L−1 with UPA and BG-11 media, respectively. Urea was found to be a preferred nitrogen source for C. aponinum. Nutrient-dosing studies with UPA medium in SCM of operation resulted in an average daily biomass productivity of ~ 0.44 g L−1 day−1, which is significantly higher than those reported in previous studies. Here, the stoichiometric requirement of nitrogen and phosphorous was found to be 31 mg L−1 and 4.5 mg L−1, respectively. Stoichiometric nutrient addition in SCM resulted in a reduction in nutrient loss in blow down. In addition, the outdoor scale-up studies in flat panel photobioreactors further established the efficacy of UPA medium. Cost analysis of media revealed that UPA medium is 4.4 times less expensive than BG-11 and hence is a suitable and economical medium for large scale cultivation of C. aponinum. Further, this nutrient feeding strategy has wider applications which can be extended to other algal strains and cultivation systems.

Influence of temperature on development, reproduction and regeneration in the flatworm model organism, Macrostomum lignano

BackgroundThe free-living marine flatworm Macrostomum lignano is a powerful model organism for use in studying mechanisms of regeneration and stem cell regulation due to its combination of biological and experimental properties, including the availability of transgenesis methods, which is unique among flatworm models. However, due to its relatively recent introduction in research, many aspects of this animal’s biology remain unknown. One such question is the influence of culture temperature on Macrostomum biology.ResultsWe systematically investigated how different culture temperatures affect development time, reproduction rate, regeneration, heat shock response, and gene knockdown efficiency by RNA interference (RNAi) in M. lignano. We used marker transgenic lines to accurately measure the regeneration endpoint, and to establish the stress response threshold for temperature shock. We found that compared to the culture temperature of 20 °C commonly used for M. lignano, temperatures of 25 °C–30 °C substantially increase the speed of development and regeneration, lead to faster manifestation of RNAi phenotypes, and increase reproduction rate without detectable negative consequences for the animal, while temperatures above 30 °C elicit a heat shock response.ConclusionsWe show that altering temperature conditions can be used to reduce the time required to establish M. lignano cultures, perform RNAi experiments, store important lines, and optimize microinjection procedures for transgenesis. These findings will help to optimize the design of experiments in M. lignano, and thus facilitate future research using this model organism.

Pat‐geom: A software package for the analysis of animal patterns

Abstract Colour patterns often influence how animals interact with one another, but the ability of researchers to quantify pattern per se is hampered by a lack of easily accessible and user‐friendly measurement software packages. We address this issue by releasing pat‐geom, a free software package for use within ImageJ that allows users to measure seven properties of a pattern: (a) the shape of its markings, (b) the directionality in the shape of its markings, (c) the size of its markings, (d) the contrast of the pattern, (e) the distribution of its markings, (f) the directionality in the distribution of its markings, and (g) the randomness of the pattern. We provide examples of how pat‐geom may be used, such as to visualise the “average pattern” of a population of animals, or to compare the patterns on two animals. Using data from two case studies, we also demonstrate pat‐geom's ability to identify the specific aspects of an organism's pattern that match its background and to design artificial prey items that accurately resemble their model organism for use in predation experiments. pat‐geom collates the tools to measure these seven diverse properties of animal colour patterns into one convenient, easy‐to‐use package. It can be employed in a wide range of studies on topics such as aposematism, camouflage and mimicry, and also has the potential to be applied to other research fields such as landscape ecology, botany and cellular biology.

Toward rational selection criteria for selection of probiotics in pigs.

An accurate understanding of properties of probiotics is a prerequisite for selecting probiotic organisms for use in swine production. This review aims to review selection criteria for probiotic organism in swine. The systematically investigated ecological history rather than the source of isolates should be regarded as the natural origin of probiotic strains, which helps to correct the inconsistencies arising from incorrect identification of the source. Moreover, in vivo studies are suggested as follow-up assessment to validate the characteristics of probiotic predicted by in vitro experiments. In addition, the intended probiotic effect depends on the age of the animal and disease prevention in young animals may require different probiotic strains when compared to growth promotion in older animals. With adequate selection criteria, the inclusion of probiotic in feed supplementation is a promising way to exert positive effects on sows, newborns, weanling animals and grower-finisher pigs. Both host-adapted probiotics and nomadic probiotics can be applied for pathogen inhibition but host adapted organisms appear to have a different mode of action. Host-adapted probiotic strains are likely to be associated with exclusive colonization while the nomadic or environmental strain exert better immune stimulating functions. Strains with potent enzymatic activity are fitter for grower pigs favoring feed digestion and enhancing growth performance.

Severe acute malnutrition.

Advances in our understanding of the treatment of severe acute malnutrition (SAM) in a resource-limited environment are needed to improve outcome. Ready-to-use therapeutic foods (RUTFs) made from local products and with reduced milk content lower costs and may be effective in older children. None of the therapeutic foods used to treat severely malnourished children correct long chain polyunsaturated fatty acid deficiencies.Routine short-term antibiotic (amoxicillin) treatment, in the context of adequate healthcare supervision, does not improve the recovery rate. Long-term antibiotic (cotrimoxazole) treatment also does not provide significant benefit to non-HIV-infected children.Increased pathogenic bacteria have been found in the intestinal microbiome of malnourished children and candidate organisms for use as probiotics have been identified. There is, however, no evidence to support the routine use of probiotics in these children. Although exocrine pancreatic function is reduced in malnourished children, routine pancreatic enzyme supplementation does not lead to accelerated recovery. Alternative RUTF may provide a cheaper and more acceptable alternative to standard RUTF in the near future. Further research is needed to understand the implications of fatty acid deficiencies and dysbiosis that occur in malnourished children. Routine antibiotic administration in the appropriate setting is unnecessary.