Read by QxMD icon Read

niche modeling

Wyatt E Lanik, Lily Xu, Cliff J Luke, Elise Z Hu, Pranjal Agrawal, Victoria S Liu, Rajesh Kumar, Alexa M Bolock, Congrong Ma, Misty Good
Human small intestinal enteroids are derived from the crypts and when grown in a stem cell niche contain all of the epithelial cell types. The ability to establish human enteroid ex vivo culture systems are important to model intestinal pathophysiology and to study the particular cellular responses involved. In recent years, enteroids from mice and humans are being cultured, passaged, and banked away for future use in several laboratories across the world. This enteroid platform can be used to test the effects of various treatments and drugs and what effects are exerted on different cell types in the intestine...
February 15, 2018: Journal of Visualized Experiments: JoVE
Sho Kurihara, Masato Fujioka, Tomohiko Yoshida, Makoto Koizumi, Kaoru Ogawa, Hiromi Kojima, Hirotaka James Okano
Hearing research has long been facilitated by rodent models, although in some diseases, human symptoms cannot be recapitulated. The common marmoset (Callithrix jacchus) is a small, easy-to-handle New World monkey which has a similar anatomy of the temporal bone, including the middle ear ossicular chains and inner ear to humans, than in comparison with that of rodents. Here, we report a reproducible, safe, and rational surgical approach to the cochlear round window niche for the drug delivery to the inner ear of the common marmoset...
February 27, 2018: Journal of Visualized Experiments: JoVE
A Leoni Swart, Christopher F Harrison, Ludwig Eichinger, Michael Steinert, Hubert Hilbi
Environmental bacteria of the genus Legionella naturally parasitize free-living amoebae. Upon inhalation of bacteria-laden aerosols, the opportunistic pathogens grow intracellularly in alveolar macrophages and can cause a life-threatening pneumonia termed Legionnaires' disease. Intracellular replication in amoebae and macrophages takes place in a unique membrane-bound compartment, the Legionella -containing vacuole (LCV). LCV formation requires the bacterial Icm/Dot type IV secretion system, which translocates literally hundreds of "effector" proteins into host cells, where they modulate crucial cellular processes for the pathogen's benefit...
2018: Frontiers in Cellular and Infection Microbiology
Joke Terryn, Tine Tricot, Madhavsai Gajjar, Catherine Verfaillie
Pluripotent stem cells have the property of long-term self-renewal and the potential to give rise to descendants of the three germ layers and hence all mature cells in the human body. Therefore, they hold the promise of offering insight not only into human development but also for human disease modeling and regenerative medicine. However, the generation of mature differentiated cells that closely resemble their in vivo counterparts remains challenging. Recent advances in single-cell transcriptomics and computational modeling of gene regulatory networks are revealing a better understanding of lineage commitment and are driving modern genome editing approaches...
2018: F1000Research
Ding Shi, Yongpan Liu, Dong Wu, Xujun Hu
Helicobacter pylori , the primary causative agent of stomach cancer, is known to affect gastric mucin expression. However, the underlying molecular mechanisms mediating this H. pylori -dependent effect remain unknown. In the present study, the effect of exogenous expression of the H. pylori virulence factor, CagA, on mucin 5AC oligomeric muscus/gel-forming (MUC5AC) expression was investigated using an in vitro model of the gastric mucosa. AGS cells were either untreated or transfected by a vector control (pCDNA3...
April 2018: Oncology Letters
T C McDonnell, S Belyazid, T J Sullivan, M Bell, C Clark, T Blett, T Evans, W Cass, A Hyduke, H Sverdrup
Ecological effects of atmospheric nitrogen (N) and sulfur (S) deposition on two hardwood forest sites in the eastern United States were simulated in the context of a changing climate using the dynamic coupled biogeochemical/ecological model chain ForSAFE-Veg. The sites are a mixed oak forest in Shenandoah National Park, Virginia (Piney River) and a mixed oak-sugar maple forest in Great Smoky Mountains National Park, Tennessee (Cosby Creek). The sites have received relatively high levels of both S and N deposition and the climate has warmed over the past half century or longer...
March 14, 2018: Environmental Pollution
Daniel Cahill, Sevin Turcan
Malignant glioma is a common type of brain tumor that remains largely incurable. Although a definitive cell of origin of gliomas remains elusive, numerous population studies, sequencing efforts, and genetically engineered mouse models have contributed to our understanding of the early events that may lead to gliomagenesis. Herein we summarize our current knowledge on the population epidemiology of gliomas, heritable genetic risk factors, the somatic events that contribute to tumor evolution, and mouse models that have shed light on the glioma cell of origin...
February 2018: Seminars in Neurology
Kaitlin C Maguire, Douglas J Shinneman, Kevin M Potter, Valerie D Hipkins
Unique responses to climate change can occur across intraspecific levels, resulting in individualistic adaptation or movement patterns among populations within a given species. Thus, the need to model potential responses among genetically distinct populations within a species is increasingly recognized. However, predictive models of future distributions are regularly fit at the species level, often because intraspecific variation is unknown or is identified only within limited sample locations. In this study, we considered the role of intraspecific variation to shape the geographic distribution of ponderosa pine (Pinus ponderosa), an ecologically and economically important tree species in North America...
March 14, 2018: Systematic Biology
Marine Landa, Stéphane Blain, Jérôme Harmand, Sébastien Monchy, Alain Rapaport, Ingrid Obernosterer
In the Southern Ocean, natural iron fertilization in the wake of islands leads to annually occurring spring phytoplankton blooms associated with enhanced heterotrophic activity through the release of labile dissolved organic matter (DOM). The aim of this study was to investigate experimentally how diatom-derived DOM affects the composition of Southern Ocean winter water bacterial communities and to identify the most responsive taxa. A bacterial community collected in the naturally iron-fertilized region off Kerguelen Island (KEOPS2 October-November 2011) was grown onboard in continuous cultures, on winter water alone or amended with diatom-derived DOM supplied at identical DOC concentrations...
March 14, 2018: FEMS Microbiology Ecology
David Kavaler, Vladimir Filkov
Stack Overflow is a popular crowdsourced question and answer website for programming-related issues. It is an invaluable resource for software developers; on average, questions posted there get answered in minutes to an hour. Questions about well established topics, e.g., the coercion operator in C++, or the difference between canonical and class names in Java, get asked often in one form or another, and answered very quickly. On the other hand, questions on previously unseen or niche topics take a while to get a good answer...
2018: PloS One
Dominique Berteaux, Marylène Ricard, Martin-Hugues St-Laurent, Nicolas Casajus, Catherine Périé, Frieda Beauregard, Sylvie de Blois
The Northern Biodiversity Paradox predicts that, despite its globally negative effects on biodiversity, climate change will increase biodiversity in northern regions where many species are limited by low temperatures. We assessed the potential impacts of climate change on the biodiversity of a northern network of 1,749 protected areas spread over >600,000 km2 in Quebec, Canada. Using ecological niche modeling, we calculated potential changes in the probability of occurrence of 529 species to evaluate the potential impacts of climate change on (1) species gain, loss, turnover, and richness in protected areas, (2) representativity of protected areas, and (3) extent of species ranges located in protected areas...
March 15, 2018: Scientific Reports
Isaac Winkler, Sonja J Scheffer, Matthew L Lewis, Kristina J Ottens, Andrew P Rasmussen, Géssica A Gomes-Costa, Luz Maria Huerto Santillan, Marty A Condon, Andrew A Forbes
BACKGROUND: Much evolutionary theory predicts that diversity arises via both adaptive radiation (diversification driven by selection against niche-overlap within communities) and divergence of geographically isolated populations. We focus on tropical fruit flies (Blepharoneura, Tephritidae) that reveal unexpected patterns of niche-overlap within local communities. Throughout the Neotropics, multiple sympatric non-interbreeding populations often share the same highly specialized patterns of host use (e...
March 14, 2018: BMC Evolutionary Biology
Terhi Tapiainen, Niko Paalanne, Mysore V Tejesvi, Pirjo Riikola M, Katja Korpela, Tytti Pokka, Jarmo Salo, Tuula Kaukola, Anna Maria Pirttilä, Matti Uhari, Marjo Renko
BACKGROUND: Meconium is formed before birth and may reflect the microbiome of the fetus. To test our hypothesis, we investigated whether maternal factors during pregnancy, such as biodiversity of the living environment, influence the microbiome of the first stool more than immediate perinatal factors. METHODS: We recruited 218 consecutive newborn infants from one hospital. Regions of the bacterial 16S rRNA gene were sequenced to characterize the microbiomes of the first-pass meconium samples (N=212)...
March 14, 2018: Pediatric Research
Belén Cotes, Mónica González, Emilio Benítez, Eva De Mas, Gemma Clemente-Orta, Mercedes Campos, Estefanía Rodríguez
The promotion of native vegetation as a habitat for natural enemies, which could increase their abundance and fitness, is especially useful in highly simplified settings such as Mediterranean greenhouse landscapes. Spiders as generalist predators may also be involved in intra-guild predation. However, the niche complementarity provided by spiders as a group means that increased spider diversity may facilitate complementary control actions. In this study, the interactions between spiders, the two major horticultural pests, Bemisia tabaci and Frankliniella occidentalis , and their naturally occurring predators and parasitoids were evaluated in a mix of 21 newly planted shrubs selected for habitat management in a highly disturbed horticultural system...
March 14, 2018: Insects
Laxman Khanal, Mukesh K Chalise, Kai He, Bipin K Acharya, Yoshi Kawamoto, Xuelong Jiang
Genetic diversity of a species is influenced by multiple factors, including the Quaternary glacial-interglacial cycles and geophysical barriers. Such factors are not yet well documented for fauna from the southern border of the Himalayan region. This study used mitochondrial DNA (mtDNA) sequences and ecological niche modeling (ENM) to explore how the late Pleistocene climatic fluctuations and complex geography of the Himalayan region have shaped genetic diversity, population genetic structure, and demographic history of the Nepalese population of Assam macaques (Macaca assamensis) in the Himalayan foothills...
March 14, 2018: American Journal of Primatology
Aastha Chhabra, Shalini Mishra, Gaurav Kumar, Asheesh Gupta, Gaurav Kumar Keshri, Brij Bharti, Ram Niwas Meena, Amit Kumar Prabhakar, Dinesh Kumar Singh, Kalpana Bhargava, Manish Sharma
Hydrogen Sulfide (H2 S), recently identified as the third endogenously produced gaseous messenger, is a promising therapeutic prospect for multiple cardio-pathological states, including myocardial hypertrophy. The molecular niche of H2 S in normal or diseased cardiac cells is, however, sparsely understood. Here, we show that β-adrenergic receptor (β-AR) overstimulation, known to produce hypertrophic effects in cardiomyocytes, rapidly decreased endogenous H2 S levels. The preservation of intracellular H2 S levels under these conditions strongly suppressed hypertrophic responses to adrenergic overstimulation, thus suggesting its intrinsic role in this process...
December 2018: Cell Death Discovery
Lindsay G Carlson, Karen H Beard, Peter B Adler
Both the direct effects of warming on a species' vital rates and indirect effects of warming caused by interactions with neighboring species can influence plant populations. Furthermore, herbivory mediates the effects of warming on plant community composition in many systems. Thus, determining the importance of direct and indirect effects of warming, while considering the role of herbivory, can help predict long-term plant community dynamics. We conducted a field experiment in the coastal wetlands of western Alaska to investigate how warming and herbivory influence the interactions and abundances of two common plant species, a sedge, Carex ramenskii , and a dwarf shrub, Salix ovalifolia ...
March 2018: Ecology and Evolution
Katja Häkli, Kjartan Østbye, Kimmo K Kahilainen, Per-Arne Amundsen, Kim Præbel
Adaptive radiation is the evolution of ecological and phenotypical diversity. It arises via ecological opportunity that promotes the exploration of underutilized or novel niches mediating specialization and reproductive isolation. The assumed precondition for rapid local adaptation is diversifying natural selection, but random genetic drift could also be a major driver of this process. We used 27 populations of European whitefish ( Coregonus lavaretus ) from nine lakes distributed in three neighboring subarctic watercourses in northern Fennoscandia as a model to test the importance of random drift versus diversifying natural selection for parallel evolution of adaptive phenotypic traits...
March 2018: Ecology and Evolution
Christopher J Anderson, John Satkovich, Volkan K Köseoğlu, Hervé Agaisse, Melissa M Kendall
Ethanolamine is a ubiquitous and essential molecule within a host. Significantly, bacterial pathogens exploit ethanolamine during infection to promote growth and regulate virulence. The ethanolamine permease EutH is dispensable for growth in vitro under standard conditions, whereas EutH is required for ethanolamine utilization at low pH. These findings suggested a model in which EutH facilitates diffusion of ethanolamine into the bacterial cell in acidic environments. To date, the ecological significance of this model has not been thoroughly investigated, and the importance of EutH to bacterial growth under physiologically relevant conditions is not known...
March 12, 2018: Infection and Immunity
Auriane Virgili, Matthieu Authier, Pascal Monestiez, Vincent Ridoux
Despite large efforts, datasets with few sightings are often available for rare species of marine megafauna that typically live at low densities. This paucity of data makes modelling the habitat of these taxa particularly challenging. We tested the predictive performance of different types of species distribution models fitted to decreasing numbers of sightings. Generalised additive models (GAMs) with three different residual distributions and the presence only model MaxEnt were tested on two megafauna case studies differing in both the number of sightings and ecological niches...
2018: PloS One
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"