Life Sciences Commons^™

A Gene Expression Profile Associated With Successful Cns Axon Regeneration In Xenopus Laevis, Jamie L. Belrose

Legacy Theses & Dissertations (2009 - 2024)

Background: The South African claw-toed frog, Xenopus laevis, is uniquely suited for studying differences between regenerative and non-regenerative responses to CNS injury within the same organism, because some CNS neurons (e.g., retinal ganglion cells after optic nerve crush (ONC)) regenerate axons throughout life, whereas others (e.g., hindbrain neurons after spinal cord injury (SCI)) lose this capacity as tadpoles metamorphose into frogs. Tissues from these CNS regions (frog ONC eye, tadpole SCI hindbrain, frog SCI hindbrain) were used in a three-way RNA-seq study of axotomized CNS axons to identify potential core gene expression programs for successful CNS axon regeneration.

Wnt Signaling Determines Body Axis Polarity In Regenerating Hydra Tissue Fragments, R. Wang, R. E. Steele, Eva-Maria S. Collins

Biology Faculty Works

How an animal establishes its body axis is a fundamental question in developmental biology. The freshwater cnidarian Hydra is an attractive model for studying axis formation because it is radially symmetric, with a single oral-aboral axis. It was recently proposed that the orientation of the new body axis in a regenerating Hydra polyp is determined by the oral-aboral orientation of the actin-myosin contractile processes (myonemes) in the animal’s outer epithelial layer. However, it remained unclear how the oral-aboral polarity of the body axis would be defined. As Wnt signaling is known to control axis polarity in Hydra and bilaterians, we …

Vegetative And Edaphic Responses In A Northern Mixed Conifer Forest Three Decades After Harvest And Fire: Implications For Managing Regeneration And Carbon And Nitrogen Pools, R. Kasten Dumroese, Martin Jurgensen, Deborah S. Page-Dumroese

Michigan Tech Publications

Research Highlights: This experiment compares a range of combinations of harvest, prescribed fire, and wildfire. Leveraging a 30-year-old forest management-driven experiment, we explored the recovery of woody species composition, regeneration of the charismatic forest tree species Larix occidentalis Nutt., and vegetation and soil carbon (C) and nitrogen (N) pools. Background and Objectives: Initiated in 1967, this experiment intended to explore combinations of habitat type phases and prescribed fire severity toward supporting regeneration of L. occidentalis. At onset of the experiment, a wildfire affected a portion of the 60 research plots, allowing for additional study. Our objective was to better understand …

Change Of Regrowth Of Seripidium Transiliensis Poljak In Different Grazing Disturbance, Shazhou An, Zongjiu Sun, Meng Tao, Falan Jin, Xianhua Zhang

IGC Proceedings (1997-2023)

No abstract provided.

Complex Tissue Regeneration In Mammals Is Associated With Reduced Inflammatory Cytokines And An Influx Of T Cells, Thomas R. Gawriluk, Jennifer Simkin, Corin K. Hacker, John M. Kimani, Stephen G. Kiama, Vanessa O. Ezenwa, Ashley W. Seifert

Biology Faculty Publications

While mammals tend to repair injuries, other adult vertebrates like salamanders and fish regenerate damaged tissue. One prominent hypothesis offered to explain an inability to regenerate complex tissue in mammals is a bias during healing toward strong adaptive immunity and inflammatory responses. Here we directly test this hypothesis by characterizing part of the immune response during regeneration in spiny mice (Acomys cahirinus and Acomys percivali) vs. fibrotic repair in Mus musculus. By directly quantifying cytokines during tissue healing, we found that fibrotic repair was associated with a greater release of pro-inflammatory cytokines (i.e., IL-6, CCL2, and CXCL1) …

Axonal Regrowth Of Olfactory Sensory Neurons After Chemical Ablation And Removal Of Axonal Debris By Microglia, Rudy Chapman

Electronic Theses and Dissertations

Olfactory sensory neurons (OSNs) are contained within the olfactory epithelium (OE) and are responsible for detecting odorant molecules in the air. The exposure of OSNs to the external environment is necessary for their function, but it also leaves them exposed to potentially harmful elements and thus results in a high turnover rate. Despite the high turnover, the olfactory sense is maintained throughout life through the division of a population of stem cells that produce new OSNs both during normal turnover and after an injury occurs in the OE. When new OSNs are born, they must extend axons from the OE …

Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel

LSU Doctoral Dissertations

Floodplain forest species diversity is driven, in part, by variation in disturbance regime. Flood patterns create heterogeneity in microsite quality from small differences in elevation across a floodplain which, in turn, influence flood timing and duration. Differences in species’ regeneration niches in relation to hydrologic patterns can account for long-term coexistence of various species. In the past century floodplain forests have exhibited a wide range of changes in stand development and species composition as a result of altered hydrology in rivers and floodplains. I evaluated the role of regeneration in floodplain forest systems of the Lower Mississippi River Alluvial Valley …

Plant Regeneration From In Vitro Stem Explants Of Dianthus Spiculifolius, Yanping Liang, Yan Sun, Qingchuan Yang

IGC Proceedings (1997-2023)

No abstract provided.

Regeneration Behaviour Of Degraded Pasture Of Lasiurus Sindicus Grass Under Different Cultural Practices In Extreme Arid Conditions Of Jaisalmer, India, Ram Narayan Kumawat, Priyabrata Santra, Nawalesh Kumar Sinha

IGC Proceedings (1997-2023)

The agriculture of seventies in the hot arid zone of India (western Rajasthan) was chiefly the subsistence farming involving rearing of livestock in association with rainfed cultivation of guar, moth and pearl millet. Pasturelands dominate among different land use systems and provide main support to the huge livestock population of the region (Kar et al., 2009). With the advent of Indira Gandhi Canal and commencement of tube-well technology in 1985, livestock based economy saw a change in the land use and large tracts of sewan grass (Lasiurus sindicus) came under the plough. Further, in arid zone as …

Development Of A Novel Cardiac Ischemia-Reperfusion Model In The Axolotl, Jeremy Tolentino Llaniguez

Wayne State University Dissertations

The Center for Disease Control’s National Center for Health Statistics data for mortality from diseases of the heart show the age-adjusted death rate has fallen from almost 600 deaths in the 1950s to just over 190 deaths per 100,000 U.S. residents today. With the recognized limitations of pharmacotherapy of myocardial infarction (MI), cell-based therapies have been undergoing rapid development and clinical testing. However, there is still no consensus about cell types, delivery routes, dosing and treatment schedules and pretreatment conditioning of cells prior to administration. Furthermore, a fundamental question remains unanswered about the reasons for the poor capacity for myocardial …

Measuring Functional Brain Recovery In Regenerating Planarians By Assessing The Behavioral Response To The Cholinergic Compound Cytisine, Oné R. Pagán, Debra L. Baker, Sean Deats, Mary O'Brien, Rochelle Dymond, Gabriella Demichele

Biology Faculty Publications

Planarians are traditional model invertebrates in regeneration and developmental biology research that also display a variety of quantifiable behaviors useful to screen for pharmacologically active compounds. One such behavior is the expression of seizure-like movements (pSLMs) induced by a variety of substances. Previous work from our laboratory showed that cocaine, but not nicotine, induced pSLMs in intact but not decapitated planarians. Interestingly, as decapitated planarians regenerated their heads, they gradually recovered their sensitivity to cocaine. These results suggested a method to assess planarian brain regeneration and a possible way of identifying compounds that could enhance or hold back brain regeneration. …

Effects Of Wild Pig Disturbance On Forest Vegetation And Soils, Steven M. Gray, Gary J. Roloff, Daniel B. Kramer, Dwayne R. Etter, Kurt C. Vercauteren, Robert A. Montgomery

USDA Wildlife Services: Staff Publications

In North America, wild pigs (Sus scrofa; feral pigs, feral swine, wild boars) are a widespread exotic species capable of creating large‐scale biotic and abiotic landscape perturbations. Quantification of wild pig environmental effects has been particularly problematic in northern climates, where they occur only recently as localized populations at low densities. Between 2016 and 2017, we assessed short‐term (within ~2 yrs of disturbance) effects of a low‐density wild pig population on forest features in the central Lower Peninsula of Michigan, USA. We identified 16 8‐ha sites using global positioning system locations from 7 radio‐collared wild pigs for sampling.Within each …

Contribution Of Advanced Regeneration Of Pinus Radiata D. Don. To Transpiration By A Fragment Of Native Forest In Central Chile Is Out Of Proportion With The Contribution To Sapwood Area, Don A. White, Richard P. Silberstein, Francisco Balocchi-Contreras, Juan Jose Quiroga, Pablo Ramirez De Arellano

Research outputs 2014 to 2021

The transpiration of Nothofagus glauca (Phil.) Krasser and advanced Pinus radiata D. Don. regeneration was measured in a fragment of native N. glauca forest. Over the eight months of this study, P. radiata contributed approximately 60% of the total stand transpiration. This was out of proportion with the approximately 34% of the stand sapwood area contributed by P. radiata. This was due to the significantly greater sap flux density of the P. radiata compared to the N. glauca between May and October. Though the results are from a small study conducted as part of a larger experiment, it is argued …

Effects Of Gap Junction Blockage On Regenerating Body Segments Of Lumbriculus Variegatus, Monica K. Richmond

Cal Poly Humboldt theses and projects

Lumbriculus variegatus is a freshwater annelid that is well known for its regenerative capacity. There are many different factors that affect regeneration in animals. Cell-to-cell communication is a key component of regeneration. Gap junctions are made up of proteins that create a channel that connects the cytoplasm of two cells. Many molecules and ions pass through the gap junctions that can affect regeneration. The purpose of this study was to determine if blocking gap junctions would have an impact on regenerating body segments of L. variegatus and what effects it would produce. L. variegatus was exposed to a known gap …

Human Organ/Limb Regeneration: A Dream Or Reality?, Shmuel Sashitzky

The Science Journal of the Lander College of Arts and Sciences

Organ and limb regeneration might seem like something out of science fiction, but research has been ongoing since the late 1960s and has greatly increased at the turn of the century. It is an understatement to say that this has the potential to be life changing. The need for donor transplant organs and transplant waiting lists can become obsolete and the use of immunosuppressants post-transplant will become unnecessary (leading to higher survival rates). Should this happen, trauma patients will be able to achieve complete recoveries and the reign of some congenital disorders will come to an end. Nature has provided …

From Organisms To Ecosystems: Impacts Of Limb Loss And Regeneration On Crayfish Behavior, Luc Arnaud Dunoyer

Theses and Dissertations--Biology

The ability of some organisms to regenerate tissues and organs has fascinated naturalists since antiquity, dating back to the earliest accounts of scientific inquiry with Aristotle in Ancient Greece. Then, Darwin’s theory invigorated some scientists’ dream of stimulating (or reactivating) regenerative capacities in human beings by showing that we are related to highly regenerative organisms. More recently, a renewed interest in discovering the molecular and genetic basis for organ and tissue regeneration has led biologists to focus more specifically on a restrictive set of model organisms.

Although the process of limb regeneration is different between invertebrate and vertebrate organisms, it …